ARTICLE | doi:10.20944/preprints202107.0015.v1
Subject: Keywords: characterization; life cycle assessment; life cycle impact assessment; normalization; particulate matter; respiratory inorganics; water vapor
Online: 1 July 2021 (11:16:42 CEST)
Life cycle assessment (LCA) is being included formally in EcoDesign regulations. Especially product carbon footprint will be mandatory in Europe. However, life cycle impact assessment including global warming potential (GWP) in LCA is hampered by several challenges. One of these is lack of water vapor characterization indexes for GWP. A life cycle inventory profile for air transport fuel including water vapor emissions is evaluated with state-of-the-art practice, i.e. EF Method and ILCD 2011 Midpoint+ and neglecting water vapors high altitude GWP compared to carbon dioxide. Then the characterization factor in GWP100 for water vapor and alternate normalization for particulates are introduced. The results are compared. The main findings are that the EF method and ILCD both generate rather realistic results for Particulate Matter and Respiratory Inorganics mid-point indicators, respectively, but the amount of premature deaths should be better allocated to different specific emissions, and that water vapor may dominate the GWP100 result over the usual carbon dioxide. LCIA mid-points need measurable and understandable bases. The common knowledge of water vapor’s GWP100 should not be neglected in LCIA for air transport and beyond where relevant.
ARTICLE | doi:10.20944/preprints202110.0441.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Life Cycle Assessment; Blockchain; Supply Chain
Online: 28 October 2021 (14:56:20 CEST)
Life Cycle Assessment (LCA) is a widely recognized tool used to evaluate environmental impacts of a product or process, based on the environmental inventory database and bills of material. Data quality is one of the most significant factors affecting the analysis results. However, currently most datasets in inventory databases are generic i.e., they may represent material and energy flow of a process at market average, instead of a specific process used by a manufacturer. As a result, stockholders are unable to track their supply chain to find out the actual environmental impact from each supplier and to compare the environmental performance of alternative options. In this paper, we developed a new framework i.e., blockchain based LCA (BC-LCA), where block-chain technology is adapted to secure and transmit inventory data from upstream suppliers to downstream manufacturers. With BC-LCA, more specific data can be acquired along the supply chain in a real-time manner. Moreover, the availability, accuracy, privacy, and automatic update of inventory data can be improved. A case study is provided based on an industrial supply chain, to demonstrate the utilization of BC-LCA.
ARTICLE | doi:10.20944/preprints202011.0438.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Life cycle assessment; circular economy; multiple product life cycles; temporal variability; life cycle inventory; emission intensity
Online: 16 November 2020 (17:24:26 CET)
Life cycle assessment (LCA) is used frequently as a decision support tool for evaluating different design choices of products based on their environmental impacts. A life cycle usually comprises several phases of varying timespan. The amount of emissions generated from different life cycle phases of a product could be significantly different from one another. In conventional LCA, the emissions generated from the life cycle phases of a product are aggregated at the inventory analysis stage, which is then used as an input for life cycle impact assessment. However, when the emissions are aggregated, the temporal variability of inventory data is ignored, which may result in inaccurate environmental impact assessment. Besides, the conventional LCA does not consider the environmental impact of circular products with multiple use cycles. It poses difficulties in identifying the hotspots of emission-intensive activities with the potential to mislead conclusions and implications for both practice and policy. To address this issue and to analyse the embedded temporal variations in inventory data in a CE context, the paper proposes to calculate the emission intensity for each life cycle phase. It is argued that calculating and comparing emission intensity, based on the timespan and amount of emissions for individual life cycle phases, at the inventory analysis stage of LCA offers a complementary approach to the traditional aggregate emission-based LCA approach. In a circular scenario, it helps to identify significant issues during different life cycle phases and the relevant environmental performance improvement opportunities through product, business model and supply chain design.
ARTICLE | doi:10.20944/preprints201805.0010.v3
Subject: Social Sciences, Organizational Economics & Management Keywords: sustainability; competitive advantage, Sassuolo tile ceramic district; Life Cycle Sustainability Assessment (LCSA); Italian ceramic industry; meso-economic level; interpretative method
Online: 13 June 2018 (09:49:25 CEST)
Talking about sustainable development refers mainly to the environmental sphere, but the concept is much broader and also takes into account the social and economic conditions. The concept of sustainability, in this sense, is linked to the compatibility between the development of economic activities, the related social phenomena, and the protection of the environment. Therefore, the ability to balance social, economic and environmental sustainability is the very meaning of the concept of sustainable development. Firms that choose to develop policies and strategies to enhance and pursue sustainable development in the medium to long term have the burden of having to quantitatively document the improvements in production processes with the aim of sustainable development. As a result, one of the biggest challenges for European industry is to introduce sustainability principles into business models leading to competitive advantage. This is particularly important in raw material and energy intensive manufacturing sectors such as the ceramic industry. The present state of knowledge lacks a comprehensive operational tool for industry to support decision-making processes geared towards sustainability. In the ceramic sector, the economic and social dimensions of the product and processes have not yet been given sufficient importance. Moreover, the traditional research on industrial districts lacks an analysis of the relations between firms and the territory with a view to sustainability. Finally, the attention of scholars in the field of economic and social sustainability, has not yet turned to the analysis of the Sassuolo district. Therefore, in this paper we introduce the Life Cycle Sustainability Assessment (LCSA), as a method that can be a suitable tool to fill this gap, because through a mathematical model it is possible to obtain the information useful for decision makers to integrate the principles of sustainability both at the microeconomic level in enterprises, and at the meso-economic level for the definition of economic policies and territorial governance. Environmental and socio-economic analysis was performed from the extraction of raw materials to the packaging of the product on different product categories manufactured by the Italian ceramic industries of the Sassuolo district (northern Italy). For the first time the LCSA model, usually applied to unitary processes, is extended to the economic and industrial activities of the entire district, extending the prospect of investigation from the enterprise and its value chain to the integrated network of district enterprises.
ARTICLE | doi:10.20944/preprints202201.0112.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Life Cycle Assessment; hydrogen production; natural gas steam reforming; biomass gasification
Online: 10 January 2022 (12:41:26 CET)
CONTEXT– Energy is widely involved in human activity and corresponding emissions of SOX, NOX and CO2 from energy generation processes affect global climate change. Clean fuels are desired by society because of their reduced greenhouse gas emissions. Hydrogen is once such candidate fuel. Much hydrogen is produced from fossil fuel, with biomass being an alternative process. OBJECTIVE– The project compared the environmental impact of hydrogen production by natural gas steam reforming vs. biomass gasification. METHOD–Environmental impact was calculated from the input and output data from life cycle inventory analysis. The impact assessment was focused on greenhouse gas emission, acidification, and eutrophication. Models of the two processes were developed and analysed in OpenLCA. The agribalyse database was used to connect inventory flow data to environmental impacts. FINDINGS– For all three metrics, biomass gasification had lower impacts than natural gas steam reforming, sometimes by large margins. For biomass gasification the silica sand production contributes most to all three impact categories, whereas for natural gas steam reforming it is the LPG extraction.
ARTICLE | doi:10.20944/preprints202110.0153.v1
Subject: Keywords: Life Cycle Assessment; Urban agriculture; Wheat; Controlled environment agriculture, Vertical garden
Online: 11 October 2021 (10:14:56 CEST)
Main purposes and research question: Wheat is the second largest grain crop by tonnage in the world and the largest in Denmark. Given the observed, adverse impacts on wheat yields of climate change and the importance of wheat in the human diet, the purpose of this study was to use life cycle assessment to compare conventional wheat farming with indoor vertical farming using hydroponics. Methods: Life Cycle Assessment was used to assess the base case systems up to the “farm gate” for 1 tonne of wheat grain. The processes contributing most of the impacts were identified, and scenarios were assessed to determine how much the impacts could be reduced. Results: The conventional system outperformed the base case vertical system in every impact category, due to the electricity consumption in the lighting system. The scenarios included increasing the efficiency of the LED lighting and using 100% wind energy, but the conventional system still outperformed the vertical system by significant margins in all impact categories. This was due to the low photosynthetic conversion efficiency and the high energy density of wheat. Conclusions: Until significant improvements are made to lighting efficiency, the photosynthesis conversion efficiency of wheat, new wheat variants designed for vertical gardens and the sustainability of electricity supply, conventional wheat production will be environmentally preferable and vertical gardens would be advised to focus on food products with low energy densities.
ARTICLE | doi:10.20944/preprints201811.0275.v1
Subject: Engineering, Civil Engineering Keywords: building; environmental impacts; façade; life-cycle assessment; transparent insulation; low-emissivity
Online: 12 November 2018 (09:36:29 CET)
Contemporary architects and the construction industry are trying to cope with increasing requirements concerning energy efficiency and environmental impact. One of the available options is the active utilization of energy gains from the environment, specifically solar energy gains. These gains can be utilized by, for example, solar walls and facades. The solar façade concept has been under development for more than a century. However, it hasn’t achieved widespread use for various reasons. Rather recently the concept was enhanced by the application of transparent insulation materials that have the potential to increase the efficiency of such façades. The presented study evaluates the environmental efficiency of 10 solar façade assemblies in the mild climate of the Czech Republic, Central Europe. The evaluated façade assemblies combine the principles of a solar wall with transparent insulation based on honeycomb and polycarbonate panels. The study applies Life-Cycle Assessment methodology to the calculation of environmental impacts related to the life cycle of the evaluated assemblies. The results indicate that even though there are several limiting factors, façade assemblies with transparent insulation have lower environmental impacts compared to a reference assembly with standard thermal insulation. The highest achieved difference is approx. 84% (in favour of the assembly with transparent insulation) during a modelled 50-year façade assembly service life.
ARTICLE | doi:10.20944/preprints201906.0084.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: manufacturing; energy efficiency; life cycle assessment; aluminium; cast-iron
Online: 11 June 2019 (06:39:26 CEST)
Considering the manufacturing of automotive components, there exists a dilemma around the substitution of traditional Cast Iron (CI) with lighter metals. Nowadays, aluminium alloys, being lighter compared to traditional materials, are considered as a more environmentally friendly solution. However, the energy required for the extraction of the primary materials and manufacturing of components is usually not taken into account in this debate. In this study, an extensive literature review has been performed to estimate the overall energy required for the manufacturing of an engine cylinder block using (a) cast iron and (b) aluminium alloys. Moreover, data from over 100 automotive companies, ranging from mining companies to consultancy firms, have been collected in order to support the soundness of this investigation. The environmental impact of the manufacturing of engine blocks made of these materials is presented with respect to the energy burden; the “cradle-to-grave approach” has been implemented to take into account the energy input of each stage of the component lifecycle starting from the resource extraction and reaching to the end-of-life processing stage. Our results indicate that although aluminium components contribute towards reduced fuel consumption during their use phase, the vehicle distance needed to be covered in order to compensate for the up-front energy consumption related to the primary material production and manufacturing phases is very high. Thus, the substitution of traditional materials with lightweight ones in the automotive industry should be very thoughtfully evaluated.
ARTICLE | doi:10.20944/preprints202107.0161.v1
Subject: Engineering, Automotive Engineering Keywords: concrete blocks; life cycle assessment; sealing masonry; structural masonry; ceramic bricks
Online: 6 July 2021 (15:18:55 CEST)
The civil construction industry is one of the sectors that most consume natural resources in the world and, consequently, one of that generate more waste. Thinking about constructive techniques that generate less impact on the environment is vital to ensure sustainable development. In this scenario, the Life Cycle Assessment (LCA) has been presented as an internationally recognized approach, that assesses the potential impact of products and services on human health and the environment, throughout its entire life cycle. Aimed to identify construction techniques and vertical closing systems that generate less impact and consumption of natural resources, the impacts generated by the life cycle of the three vertical closing systems most applied in construction sites in Brazil were compared: ceramic brick masonry system (CBr); concrete block masonry system (CBk); and structural blocks masonry system (SBk). The SBk proved to be the least impacting to the “Resource Scarcity”, “Damage to Human Health”, and “Damage to the diversity of Ecosystems” interesting areas. This performance is directly related to the use of cement CPIII type and also by the fact that the SBk consumes less concrete and mortar than the others. Already the "Water Consumption" area, the CBk was the least impacting due to the lower consumption of electricity during its life cycle. The reliability of the results was proven through a sensitivity analysis of the normalization and characterization factors, which consisted of comparing the results obtained by applying two different methodologies. It is believed that the LCA study carried out can assist in the decision-making process regarding the choice of the most sustainable construction method.
ARTICLE | doi:10.20944/preprints201711.0030.v1
Subject: Earth Sciences, Environmental Sciences Keywords: packaging; hazardous chemicals; life cycle assessment (LCA); grey model (GM); IBCs; carbon footprint (CF)
Online: 6 November 2017 (04:55:20 CET)
The purpose of this paper was to analyze the development trend of hazardous chemical packaging towards low carbon economy from both qualitative and quantitative perspectives. Four types of relatively small volume packaging with volume/weight less than 450L/400kg, respectively, and three intermediate bulk containers (IBCs), which are widely used for hazardous chemicals were studied to calculate the carbon footprint (CF) from cradle to grave using life cycle assessment (LCA) method and to predict the future carbon emission of hazardous chemical packaging in the next five years (2016-2020), based on the export data of Tianjin Port in China. Grey model (GM) was adopted in the prediction. The results showed that majority of IBCs have lower carbon footprint than other types when the packaging contained same amount of same hazardous chemical. With the development of international trading, the demand of hazardous chemicals will increase as well. As the result, carbon emission generated by hazardous chemical packaging will increase accordingly. However, based on GM simulation result, increasing the amount of IBC use will effectively reduce the relative amount of carbon emission.
ARTICLE | doi:10.20944/preprints202107.0276.v1
Subject: Earth Sciences, Atmospheric Science Keywords: life cycle assessment; sisal production; circular economy; nutrient depletion; anaerobic digestion; waste management; bioenergy; biogas.
Online: 12 July 2021 (23:02:10 CEST)
Nutrient depletion in Tanzanian sisal production has led to yield decreases over time. We use nutrient mass balances embedded within a life cycle assessment to quantify the extent of nutrient depletion for different production systems, then used circular economy principles to identify potential cosubstrates from within the Tanzanian economy to anaerobically digest with sisal wastes. The biogas produced is then used to generate bioelectricity and the digestate residual can be used as a fertilizer to address the nutrient depletion. If no current beneficial use of the cosubstrate was assumed, then beef manure and marine fish processing waste were the best cosubstrates. If agricultural wastes were assumed to have a current beneficial use as fertilizer, then marine fish processing waste and human urine were the best cosubstrates. The largest reduction in environmental impacts resulted from bioelectricity replacing electricity from fossil fuels in the national electricity grid and improved onsite waste management practices. There is significant potential to revitalize Tanzanian sisal production by applying circular economy principles to sisal waste management and bioenergy production.
ARTICLE | doi:10.20944/preprints202007.0673.v1
Subject: Engineering, Automotive Engineering Keywords: life cycle assessment; agent-based traffic simulation; battery electric vehicles; sustainability; urban transportation; urban mobility; environmental engineering
Online: 28 July 2020 (10:13:30 CEST)
The transport sector in Germany causes one-quarter of energy-related greenhouse gas emissions. One potential solution to reduce these emissions is the use of battery electric vehicles. Although a number of life cycle assessments have been conducted for these vehicles, the influence of a transport system wide transition has not been researched sufficiently. Therefore, we developed a method which combines life cycle assessment with an agent-based transport simulation and synthetic electric, diesel and gasoline powered vehicle models. We use the transport simulation to obtain the number of vehicles, their lifetime mileage and road-specific consumption. Subsequently we analyze the product systems’ vehicle production, use phase and End-of-Life. The results are scaled depending on the covered distance, the vehicle weight and the consumption for the whole life cycle. The results indicate that the sole transition of drive trains is insufficient to significantly lower the greenhouse gas emissions. However, sensitivity analyses demonstrate that there is a considerable potential to reduce greenhouse gas emissions with higher shares of renewable energies, a different vehicle distribution and a higher lifetime mileage. The method facilitates the assessment of the ecological impacts of the complete car based transportation in urban agglomerations and is able to analyze different transport sectors.
ARTICLE | doi:10.20944/preprints202101.0590.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Environment; ·Comprehensive treatmen; ·public-private partnerships (PPP); ·Full life cycle; ·Risk assessmen; ·Principal component analysis (PCA)
Online: 28 January 2021 (15:39:03 CET)
China's implementation of public-private partnerships projects has been quite effective, involving infrastructure and other livelihood projects, a total of 19 industries, and an investment of nearly 1.5 trillion yuan. The characteristics of PPP projects such as long construction period and large investment amount determine the risks of PPP projects are also great, and the PPP projects of comprehensive environmental governance are also the same. The government and social capital use the PPP model to cooperate, and use the principal component analysis method to assess the risks of the entire life cycle of the comprehensive environmental governance PPP project. Therefore, it plays an important role in ensuring the smooth implementation of projects and reducing the losses caused by risks. According to the risk factors of the whole life cycle of the comprehensive environmental governance PPP project, an indicator system of 5 first-level indicators, 18 second-level indicators, and 43 third-level indicators has been established. Principal component analysis is used to analyze the influence weight of risk factors at each stage. The analysis shows that among the four stages, environmental pollution risk, project approval delay risk, completion risk, interest rate and financial fluctuation risk, and franchise life risk are the most influential risks in the implementation of PPP projects. Therefore, suggestions are made through the risk factors of each stage in the comprehensive environmental governance PPP project. For example, strengthen the response to the external environment risks of the comprehensive environmental governance PPP project, standardize the bidding and procurement of the comprehensive environmental governance PPP project, and strengthen the subsequent management of the transfer of the comprehensive environmental governance PPP project. In this way, the ability to resist risks of comprehensive environmental governance PPP projects is improved; the smooth implementation of the project is guaranteed, and the long-term development of comprehensive environmental governance PPP projects is promoted.
ARTICLE | doi:10.20944/preprints202110.0399.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Renewable energy; Life cycle analysis; Wind energy; Life cycle assessment; Wind turbine; Carbon footprint; Water consumption; Greenhouse gases; non-conventional renewable sources; Carbon and water footprints.
Online: 27 October 2021 (11:00:58 CEST)
Wind technology is considered to be among the most promising types of renewable energy sources, and due to high oil prices and growing concerns about climate change and energy security, it has been the subject of extensive considerations in recent years, including questions related to the relative sustainability of electricity production when the manufacturing, assembly, transportation and dismantling processes of these facilities are taken into account. The present article evaluates the environmental impacts, carbon emissions and water consumption, derived from the production of electric energy of the Villonaco wind farm, located in Loja-Ecuador, during its entire life cycle, using the Life Cycle Analysis method. Finally, it is concluded that wind energy has greater environmental advantages, since it has lower values of carbon and water footprints than other energy sources. Additionally, with the techniques Cumulative Energy Demand and Energy Return on Investment, sustainability in the production of electricity from wind power in Ecuador is demonstrated; and, that due to issues of vulnerability to climate change, the diversification of its energy mix is essential considering the inclusion of non-conventional renewable sources such as solar or wind, this being the only way to reduce both the carbon footprint and the water supply power.
ARTICLE | doi:10.20944/preprints201901.0201.v1
Subject: Social Sciences, Finance Keywords: corporate life-cycle; bankruptcy risk; financial sustainability; Pakistan
Online: 21 January 2019 (09:10:39 CET)
In this paper we analyze the relationship between bankruptcy risk and the corporate life cycle in Pakistan from 2005 to 2014. For this purpose, we run a Hierarchical Linear Mixed Model (HLM) for a sample of 301 non-financial listed firms in 12 different sectors. The empirical outcomes reveal that firms during introduction, growth and, decline stages (mature stage) of life-cycle experience higher (lower) bankruptcy risk. Moreover, in juxtaposition with growth stage, bankruptcy risk is higher at the introduction stage of life-cycle. These findings suggest that financial managers should be cautious about the financial fragility of the firm at each stage of corporate life-cycle. The results also entail that Pakistani firms do not follow a sequential pattern in their life-cycle rather they have the tendency to revert to a previous stage or jump to the next stage of life-cycle. This is the first study that empirically examines the association between firm life-cycle stage and corresponding bankruptcy risk and asserts that managers must incorporate the life-cycle effects into their financial planning and decision making for sustainable working of an enterprise.
Subject: Engineering, Civil Engineering Keywords: life extension; wind turbines; end-of-life issues; probabilistic modelling; economic optimization; fatigue; risk; remaining useful life
Online: 18 January 2021 (15:02:18 CET)
Reassessment of the fatigue life for wind turbines structural components is typically performed using deterministic methods with the same partial safety factors as used for the original design. However, in relation to life extension, the conditions are generally different from the assumptions used for calibration of partial safety factors; and using a deterministic assessment method with these partial safety factors might not lead to optimal decisions. In this paper, the deterministic assessment method is compared to probabilistic and risk-based approaches, and the economic feasibility is assessed for a case wind farm. Using the models also used for calibration of partial safety factors in IEC61400-1 ed. 4 it is found that the probabilistic assessment generally leads to longer additional fatigue life than the deterministic assessment method. The longer duration of the extended life can make life extension feasible in more situations. The risk-based model is applied to include the risk of failure directly in the economic feasibility assessment and it is found that the reliability can be much lower than the target for new turbines, without compromising the economic feasibility.
ARTICLE | doi:10.20944/preprints201810.0273.v1
Subject: Physical Sciences, Astronomy & Astrophysics Keywords: astroparticle physics, cosmic rays, data life cycle management, data curation, meta data, big data, deep learning, open data
Online: 12 October 2018 (14:48:32 CEST)
Modern experimental astroparticle physics features large-scale setups measuring different messengers, namely high-energy particles generated by cosmic accelerators (e.g. supernova remnants, active galactic nuclei, etc): cosmic and gamma rays, neutrinos and recently discovered gravitational waves. Ongoing and future experiments are distributed over the Earth including ground, underground/underwater setups as well as balloon payloads and spacecrafts. The data acquired by these experiments have different formats, storage concepts and publication policies. Such differences are a crucial issue in the era of big data and of multi-messenger analysis strategies in astroparticle physics. We propose a service ASTROPARTICLE.ONLINE in the frame of which we develop an open science system which enables to publish, store, search, select and analyse astroparticle physics data. The cosmic-ray experiments KASCADE-Grande and TAIGA were chosen as pilot experiments to be included in this framework. In the first step of our initiative we will develop and test the following components of the full data life cycle concept: (i) describing, storing and reusing of astroparticle data; (ii) software for performing multi-experiment and multi-messenger analyses like deep-learning methods; (iii) outreach including example applications and tutorial for students and scientists outside the specific research field. In the present paper we describe the concepts of our initiative, and in particular the plans toward a common, federated astroparticle data storage.
ARTICLE | doi:10.20944/preprints202010.0603.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Consequential LCA; System expansion; Life Cycle Assessment; flax fiber biobased materials; bioeconomy
Online: 29 October 2020 (09:27:42 CET)
Flax fiber appears as a suitable feedstock in the endeavor of deploying a sustainable biobased economy. Its environmental performance as reinforcement in composite materials has been studied in previous Life Cycle Assessments (LCAs). However, these studies only present a coarse Life cycle Inventory (LCI) and often fail to detail all processes of the supply chain or to represent the co-products. This paper aims to bridge this gap and provide data for future LCAs on flax fiber production and transformation.The study focuses on the impacts of producing a bio-based reinforcement material (a fabric product for non-aesthetic purposes) with a system expansion perspective. The functional unit is defined as the production of 2400 m² flax-based technical textile per year, this corresponds to one hectare of cultivated land. The geographical scope considers that the production occurs in France and that some manufacturing process are outsourced in China. A Sensitivity Analysis was carried out to assess the influence of the electricity mix in the various countries involved in the manufacturing cycle.A detailed life cycle inventory for flax fiber production and transformation was built and the environmental performance of a flax technical textile was assessed as a cradle-to-gate LCA. The fate of co-products was documented and was shown to contribute to the reduction of the generated environmental impacts. Through a cradle-to-gate LCA, a broader understanding of the environmental performance of a flax-based technical textile was presented by including the valorization of co-products and a wider set of analyzed impact categories, going therefore beyond the existing state-of-the-art. Results show agricultural activities and electricity production to be the biggest contributors to the environmental impacts of flax technical textile; contributions due to land use changes were minor in comparison. Very specifically for this case study, a sensibility analysis showed the influence of an all-French production to be more efficient from an environmental point of view.
Subject: Social Sciences, Business And Administrative Sciences Keywords: vendor selection; product life cycle; multi-objective linear programming; Multi-choice goal programming.
Online: 3 June 2019 (09:52:41 CEST)
The framework of product life cycle (PLC) cost analysis is one of the most important evaluation tools for a contemporary high-tech company in an increasingly competitive market environment. The PLC-purchasing strategy provides the framework for a procurement plan and examines the sourcing strategy of a firm. The marketing literature emphasizes that ongoing technological change and shortened life cycles are important elements in commercial organizations. From a strategic viewpoint, the vendor has an important position between supplier, buyer and manufacturer. The buyer seeks to procure the products from a set of vendors to take advantage of economies of scale and to exploit opportunities for strategic relationships. However, previous studies have seldom considered vendor selection (VS) based on PLC cost (VSPLCC) analysis. The purpose of this paper is to solve the VSPLCC problems considering the situation of a single-buyer-multiple-supplier. For this issue, a new VSPLCC procurement model and solution procedure are derived by this paper to minimize net cost, rejection rate, late delivery and PLC cost subject to vendor capacities and budget constraints. Moreover, a real case in Taiwan is provided to show how to solve the VSPLCC procurement problem.
ARTICLE | doi:10.20944/preprints202112.0218.v1
Subject: Engineering, Mechanical Engineering Keywords: concrete; remote sensing; remaining life assessment; condition assessment
Online: 13 December 2021 (17:45:55 CET)
Concrete condition assessing penetrometers need to be able to distinguish between making contact with a hard (concrete) surface as opposed to a semi-solid (corroded concrete) surface. If a hard surface is mistaken for a soft surface, concrete corrosion may be over-estimated, with the potential for triggering unnecessary remediation works. Unfortunately, the variably-angled surface of a concrete pipe can cause the tip of a force-sensing tactile penetrometer to slip and thus to make this mistake. We investigated whether different shaped tips of a cylindrical penetrometer were better than others at maintaining contact with concrete and not slipping. We designed a range of simple symmetric tip shapes, controlled by a single superellipse parameter. We performed a finite element analysis of these parametric models in SolidWorks before machining in stainless steel. We tested our penetrometer tips on a concrete paver cut to four angles at 20∘ increments. The results indicate that penetrometers with a squircle-shaped steel tip (a=b=1,n=4) have the least slip, in the context of concrete condition assessment.
ARTICLE | doi:10.20944/preprints202111.0183.v1
Subject: Social Sciences, Accounting Keywords: China; Corporate Life Cycle; Corporate Performance; Corporate Social Responsibility; Pharmaceutical Industry
Online: 9 November 2021 (14:40:54 CET)
The study examines the relationship between corporate social responsibility (CSR) and the corporate life cycle (CLC) of the Chinese pharmaceutical listed companies for the duration of 2010 to 2018. The firm cash flow pattern is used as a proxy for the CLC. The study results indicate that the relationship between CSR and CLC is positive and linear in all the phases of the CLC including, the introduction, growth and maturity stage. Although the relationship is smaller and more significant at the maturity phase. The research further shows that investors incorporating social responsibilities values play a key role in the firm cash flow performance (CFP) across all the firm stages. Whilst, employees espousing social responsibility tenets can only improve CFP in the decline or shakeout stages. Likewise, embedding CSR into the customers group only improves CFP at the maturity stage. Applying the lag effects lead to the same study results. The finding for the bi-directional causality indicates that although CSR can positively influence CFP, CFP is ultimately more associated with the firm unobservable characteristics rather than performance attributed to CSR. On the whole, our study results point to positive causality between CSR and CFP across all the firm life stages and the CSR has a mediating effect on each life cycle.
Subject: Engineering, Automotive Engineering Keywords: internal combustion engine vehicle; life cycle assessment (LCA); energy analysis
Online: 27 November 2020 (07:27:37 CET)
The environmental safety of a car is currently one of the most important indicators of the vehicle competitiveness and quality in the consumer market. Currently, the assessment of the ecological properties of vehicles can be made based on various criteria. In the case of combustion-powered cars, the most attention is usually paid to the values characterizing their use, and in the environmental assessment, first of all to pollutant emissions and operational fuel consumption. The proposed article considers the possibility of using the life cycle assessment to analyze the ecological properties of a passenger car during its operation. A simplified LCA method of the vehicle was presented, which in strictly defined cases can be used for the analysis of environmental impacts and the assessment of the energy analysis related to its operation. For this purpose, a vehicle life cycle model was developed. Data on the operation of 33 passenger cars of different manufacturers with similar operational characteristics, coming from different production periods, were analyzed in detail. The obtained results were found to be highly sensitive to the assumptions made in the article.
ARTICLE | doi:10.20944/preprints201703.0135.v1
Subject: Engineering, Mechanical Engineering Keywords: corrosion fatigue; characteristic life prediction; 25CrMo steel; microscopic analysis; Weibull distribution
Online: 17 March 2017 (05:11:02 CET)
The effects of environmental media on the corrosion fatigue fracture behavior of 25CrMo steel were investigated. The media include air, and a 3.5 wt.% and a 5.0 wt.% NaCl solutions. Experimental results indicate that the media induces the initiation of corrosion fatigue cracks at multiple sites. The multi-cracking sites cause the changes in the crack growth directions, the crack growth rate during the coupling action of the media and the stress amplitude. The coupling effects are important for engineering applications and research. The probability and predictions of the corrosion fatigue characteristic life can be estimated using the 3-parameter Weibull distribution function.
ARTICLE | doi:10.20944/preprints202111.0001.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Life cycle analysis; biomethane; diesel; natural gas; SimaPro; Ecoinvent
Online: 1 November 2021 (10:14:08 CET)
The Life Cycle Analysis (LCA) was used to assess the impact of biomethane plant of the “La Católica” in Pedregal-Majes-Arequipa farm, fed with cow manure and holding a production of 60 Nm3/day of purified biogas. Life cycle inventory, impact assessment and interpretation were performed. The functional unit established was 1 MJ of energy produced; the study was modeled with SimaPro software, Ecoinvent Database and ReCiPe Midpoint (H) impact assessment methodology, according to the impact categories of climate change and fossil resource depletion. The impact analysis was limited to the Well to Tank (WTT) approach, which involves feedstock transport, substrate mixed, anaerobic digestion, biogas purification, storage and injection of the fuel into transport vehicles. The digestion process generated the highest amount of CO2 emissions (1.79E-02 kg CO2 eq/MJ-biomethane) and the highest depletion of fossil resources (6.58E-03 kg oil eq/MJ-biomethane), compared to the other fuel production, due to energy consumption and transport infrastructure. Biomethane was then compared to fossil fuels, resulting in natural gas generating the least amount of CO2 emissions, followed by diesel and finally biomethane. For the fossil resource depletion category, biomethane presented the lowest amount of fossil fuel consumption (1.37E-02 kg oil eq/MJ-biomethane), followed by natural gas and diesel.
ARTICLE | doi:10.20944/preprints202002.0413.v1
Subject: Engineering, Energy & Fuel Technology Keywords: geothermal energy; life cycle analysis; solar photovoltaic energy; wind energy
Online: 28 February 2020 (01:34:44 CET)
A Life Cycle Analysis was performed considering three existing power plants of comparable size operating with different sources of renewable energy: geothermal, solar and wind. Primary data were used for building the life cycle inventories. The geothermal power plant includes emissions treatment for removal of hydrogen sulfide and mercury. The scenario about the substitution of natural emissions from geothermal energy, with specific reference to the greenhouse effect, is also investigated performing a sensitivity analysis. The results are characterized employing a wide portfolio of environmental indicators employing the Recipe 2016 and the ILCD 2011 Midpoint+ methods; normalization and weighting are also applied using the Recipe 2016 method at endpoint level. The results demonstrate a good eco-profile of geothermal power plant with respect to other renewable energy systems and allow for a critical analysis to support potential improvements of the environmental performances.
ARTICLE | doi:10.20944/preprints202112.0190.v1
Subject: Engineering, Civil Engineering Keywords: sustainability; concrete; assessment; performance; service life; environment.
Online: 10 December 2021 (14:40:53 CET)
The article presents an original method to assess the sustainability of concrete. The method uses three parameters, namely: performance, lifetime and environmental impact, to calculate a sustainability index. The originality and the simplicity of the proposed method presented in the article consists in the fact that by applying the relation to determine the sustainability index, the first two factors service life and performance are constant. This approach is possible in the context of the new proposals to specify the durability of structural concrete in EN 1992 and EN 206. That allows classification of concrete according to its performance, through Environmental action Resistance Classes (ERC). For this purpose, specific experimental methods were used in order to determine the performance of concrete exposed to carbonation. The concretes were prepared with two cement types with additions (CEM II / A-S and CEM II / A-M (S-LL)). Based on the carbonation resistance classes (the first constant - the performance) and exposure classes, the thickness of the concrete cover layer was determined to ensure a certain service lifetime (second constant - the service lifetime). Finally, the global warming potential was calculated for each composition, consequently allowing the users of the method, to select the compositions with the lowest impact on the environment.
ARTICLE | doi:10.20944/preprints202111.0232.v1
Subject: Engineering, Civil Engineering Keywords: sustainability; concrete; assessment; performance; service life; environment.
Online: 12 November 2021 (15:12:23 CET)
This article presents a method to assess the sustainability of concrete based on three elements: service life, performance and environmental impact. The method proposes - to achieve similar performance and service life times, regardless of the component materials used, so that the sustainability assessment ultimately depends on the environmental impact criterion. To this end, specific experimental methods are used to determine the performance of concrete in terms of compressive strength and carbonation resistance for concrete cast with two blended cement types. The procedure needed to classify the concrete through carbonation resistance is detailed, in relationship with the performance obtained for compressive strength. The obtained results highlight the concrete formulations to be used to ensure similar performances regardless of the cement type used. In conclusion, the simplicity in the application of the method, which is closely related to the performance approach on concrete durability in the revision proposals of the European standards, is highlighted. The method is also a useful tool to encourage the widespread use in concrete formulation of blended cements with low environmental impact, without reducing the performance or service life time of the constructions.
ARTICLE | doi:10.20944/preprints201608.0227.v1
Subject: Engineering, Civil Engineering Keywords: railway noise; railway vibration; squeal noise vibration; screeching noise vibration; impact noise vibration; abatement; mitigation; life cycle analysis
Online: 29 August 2016 (12:39:40 CEST)
The railway industry focus in the past years was to research, find and develop methods to mitigate noise and vibration resulted from wheel/rail contact along track infrastructure. This resulted in a wide range of abatement measures that are available for the professionals of the industry today. However, although there are many options in the market, their practical implementations depend upon general constraints that affect most technological application in the engineering world. The progression of these technologies have facilitated the selection of more adequate methods for each best case scenario, but further studies are ought to be made to proper assess if each one is fit for their purpose. Every method implementation must be analyzed through budget and timeframe limitations, which includes building, maintenance and inspection costs and time allocation, while also aiming to meet different benefits, such as environmental impact control and wear of the whole infrastructure. There are several situations and facilities in a railway project design that need noise and vibration mitigation methods and each design allocates different priorities for each one of them. Traditionally the disturbance caused by railways to the community are generated by wheel/rail contact sound radiation that expresses in different ways, depending on the movement of the rolling stock and track alignment, such as rolling noise, impact noise and curve noise. More specifically, in special trackworks such as turnouts, the main area of this study, there are two noises types that must be evaluated: impact noise and screeching noise. With respect to the second, it is similar to curve squeals and, being such, its mitigation methods are to be assigned as if it was to abate curve squeal in turnouts and crossings. The impact noise on the other hand, emerges from the sound made by the rolling stock moving through joints and discontinuities (i.e. gaps) that composes these special components of a railway track. A life cycle analysis is therefore substantial for this reality and in this case will be applied to Squeal and Impact Noise on Special Trackwork. The evaluation is based on a valid literature review and the total costs were assumed by industry reports to maintain coherency. The period for a life cycle analysis is usually of 50 years, hence it was the value assumed. As for the general parameters, an area with high density of people was considered to estimate the values for a community with very strict limits for noise and vibration.
ARTICLE | doi:10.20944/preprints202210.0335.v1
Subject: Materials Science, Nanotechnology Keywords: lithium-sulfur batteries; single-walled carbon nanohorns; long cycle life; sustainable synthesis process
Online: 21 October 2022 (11:24:47 CEST)
The preparation of sulfur-single walled carbon nanohorns active material via a simple and sustainable evaporation method for application as cathode in lithium-sulfur batteries is reported. We show that the synthesis process enables the infiltration of elemental sulfur within the carbon nanohorns thus obtaining a morphology responsible for the ameliorating of the shuttle effect. The sulfur-carbon composite is characterized in terms of structure, morphology, and composition through x-ray diffraction, transmission electron microscopy, and thermogravimetric analyses. From the electrochemical point of view, cyclic voltammetry, rate capability, and galvanostatic cycling tests are performed employing a solution of bis(trifluoromethane)sulfonimide lithium salt and lithium nitrate in a mixture of 1,2-dimethoxyethane and 1,3-dioxolane in order to evaluate the electrode design applicability within lithium-sulfur cells. In this respect, further insights are provided by the estimation of the lithium-ion diffusion coefficient through the Randles-Sevcik equation, and by electrochemical impedance spectroscopy. The obtained results reveal a remarkable cycle life lasting around 800 cycles with a stable capacity of 520 mA h g-1 for the first 400 cycles at C/4, while reaching a value around 300 mA h g-1 at the 750th cycle. These results suggest sulfur-carbon nanohorns active material as a potential candidate for the next-generation battery technology.
ARTICLE | doi:10.20944/preprints202012.0291.v1
Subject: Engineering, Civil Engineering Keywords: information technology; construction project management; cost management; impact factor model; progressive technology; construction industry, life cycle cost management.
Online: 11 December 2020 (16:12:55 CET)
Construction project management and cost management is a difficult process that affects the overall success of construction projects. The success of a construction project can be assessed according to key performance indicators (KPIs). Cost savings and cost optimization over the life of a construction project is one of these KPIs. Cost management is largely performed through intelligent information technology in the construction industry. Information systems and information technologies have seen an increase in use in the management of construction projects. The same goes for cost management. Several studies mentioned in the paper point to this increase in use in recent years also in the management of costs at various stages. Many studies point to the use of information technology and software applications in the field of cost management. Still, to a large extent, there are no surveys focused on the analysis of the impact and impact factor of information technology on cost savings or cost optimization in various phases of construction projects. The research discusses the issue of the impact of information technology on cost management in various phases of a construction project. The main goal of the research is to analyze the influence of information technology factors on cost savings and optimization in individual phases of a construction project. Several statistical methods were used in the research. The resulting model of information technology impact factor was created based on data processing and the use of the AHP method.
ARTICLE | doi:10.20944/preprints201907.0016.v1
Subject: Engineering, Civil Engineering Keywords: Remote sensing; Photogrammetry; Life cycle modeling; Time series forecasting; Structural damage; Stochastic modeling; Convex Hull; ARIMA; VAR; Fatigue crack prediction
Online: 1 July 2019 (12:23:16 CEST)
The evaluation of geometric defects is necessary in order to maintain the integrity of structures over time. These assessments are designed to detect damages of structures and ideally help inspectors to estimate the remaining life of structures. Current methodologies for monitoring structural systems, while providing useful information about the current state of a structure, are limited in the monitoring of defects over time and in linking them to predictive simulation. This paper presents a new approach to the predictive modeling of geometric defects. A combination of segmented from point clouds are parametrized using the convex hull algorithm to extract features from detected defects, and a stochastic dynamic model is then adapted to these features to model the evolution of the hull over time. Describing a defect in terms of its parameterized hull enables consistent temporal tracking for predictive purposes, while implicitly reducing data dimensionality and complexity as well. In this study, 2D point clouds analogous to information derived from point clouds were first generated over simulated life-cycles. The evolutions of point cloud hull parameterizations were modeled as stochastic dynamical processes via autoregressive integrated moving average (ARIMA) and vectorized autoregression (VAR) and compared against ground truth. The results indicate that this convex hull approach provides consistent and accurate representations of defect evolution across a range of defect topologies and is reasonably robust to noisy measurements, however assumptions regarding the underlying dynamical process play a significant the role in predictive accuracy. The results were then validated on experimental data from fatigue testing with high accuracy. Longer term, the results of this work will support finite element model updating for predictive analysis of structural capacity.
ARTICLE | doi:10.20944/preprints202107.0047.v1
Subject: Social Sciences, Accounting Keywords: supplier selection; product life cycle cost; geometric averaging-weighting; penalty weighting; multiobjective linear programming; revised multichoice goal programming.
Online: 2 July 2021 (10:11:13 CEST)
Today’s purchasing companies demand an advanced buyer equal of enactment from their supplier while the two parties maintain a respectful connection. Although the supplier selection (SC) product life cycle cost (SCPLCC) is an important consideration among corporations, SCPLCC problem has become associated with deciding how one supplier should be selected from possible alternatives. In this study, we applied two types of goal programming, multiobjective linear programming and revised multichoice goal programming to develop a PLCC-based concept to solve the SCPLCC problem and construct a decision-making tool for application to a case of supply chain management in a Taiwanese light-emitting diode company in the high-tech industry. Our study main contribution Company managers can easily use the two approaches of the SCPLCC model with different parameters to solve SCPLCC model problems. Finally, we comparing five models found RMCGP with weighted linear goal programming had an adequate effect for application to the PLCC concept for high-technology comapny; this cloud make company decision–makers focus on low PLCC and select better supplier.
ARTICLE | doi:10.20944/preprints202107.0373.v1
Subject: Social Sciences, Business And Administrative Sciences Keywords: supplier selection; social product life cycle cost; sustainable supply chain; multiobjective linear programming; revised multichoice goal programming.
Online: 16 July 2021 (14:05:52 CEST)
Supplier selection (SC) product life cycle cost (SCPLCC) is an important consideration among corporations, SCPLCC problem has become associated with deciding how one supplier should be selected from possible alternatives. In this study, we applied two types of goal programming, multiobjective linear programming and revised multichoice goal programming to develop a PLCC-based concept to solve the SCPLCC problem and construct a decision-making tool for application to a case of supply chain management in a Taiwanese light-emitting diode company in the high-tech industry. Our study main contribution Company managers can easily use the two approaches of the SCPLCC model with different parameters to solve SCPLCC model problems. Finally, we comparing five models found RMCGP with weighted linear goal programming had an adequate effect for application to the PLCC concept for high-technology company; this cloud makes company decision–makers focus on low PLCC and select a better supplier in sustainable supply chains goal.
ARTICLE | doi:10.20944/preprints201807.0067.v1
Subject: Engineering, Construction Keywords: life-cycle analysis (LCA); sustainable materials; sustainability climate impact; bioclimatic architecture; green buildings
Online: 4 July 2018 (10:27:22 CEST)
The construction industry is responsible for 40 to 45% of primary energy consumption in Europe alone. Therefore, it is essential to find new materials with a lower environmental impact in order to attain sustainable housing. This study aims to determine and compare the environmental impact of two clay samples forming a basis for the manufacture of traditional brick, a standard material in building construction; traditional red clay brick and a brick based on clay mixed with a biological ingredient. The samples of fired clay were manufactured at the laboratory scale, the results being valid exclusively as indicators for the extrapolation of the analysis to other studies. The results of the environmental impact of these formulations have been examined through an evaluation of life-cycle analysis (LCA), observing that the incorporation of biological pore forming agents led to a decrease of around 15 to 20% of all impact categories studied. Thus, the suitability of using biological-based additives in clay bricks was confirmed both for their constructive characteristics (lighter material) and increased energy efficiency (better thermal insulation) considering the environmental point of view.
ARTICLE | doi:10.20944/preprints202110.0254.v1
Subject: Engineering, Civil Engineering Keywords: compaction; environmental impacts; life cycle assessment; municipal solid waste; transportation
Online: 18 October 2021 (15:34:29 CEST)
Municipal solid waste management is a major concern for developing countries all over the world. The collection and transportation accounts for major portion of expenditure in developing country like India. The compaction of waste is being practiced in some major cities of India as they provide economical benefit but the environmental benefits of compaction are not very clear. The preset study evaluates the environmental impacts due to transportation of non-compacted and compacted waste from the transfer station to the landfill site using life cycle assessment approach. The study compared transportation of non-compacted waste with the waste compacted by the truck mounted refuse compactor and portable stationary compactor. The functional unit defined was the amount of waste generated per day in the study area taken as Patna city and GaBi 10.5 used for impact assessment. The study found that the transportation of waste compacted by truck mounted refuse compactor had the least environmental impacts on all impact categories. The study recommends the compaction of waste by the truck mounted refuse compactor and then proceed for transportation. Also, the compaction of waste is recommended as it improve the overall environment performance of municipal solid waste management.
ARTICLE | doi:10.20944/preprints202107.0188.v1
Subject: Social Sciences, Accounting Keywords: supplier selection; product life cycle cost; geometric averaging-weighting; multiobjective linear programming; revised multichoice goal programming
Online: 8 July 2021 (10:05:29 CEST)
Using the PLCC advantages generates revenue and lowers costs more than might be anticipated. It ensures better decisions by using a more perfect and practical assessment of revenues and costs. Although the supplier selection (SC) product life cycle cost (SCPLCC) is an important consideration among corporations, SCPLCC problem has become associated with deciding how one supplier should be selected from possible alternatives. In this study, we applied two types of goal programming, multiobjective linear programming and revised multichoice goal programming to develop a PLCC-based concept to solve the SCPLCC problem and construct a decision-making tool for application to a case of supply chain management in a Taiwanese light-emitting diode company in the high-tech industry. Our study main contribution Company managers can easily use the two approaches of the SCPLCC model with different parameters to solve SCPLCC model problems. Finally, we comparing five models found RMCGP with weighted linear goal programming had an adequate effect for application to the PLCC concept for high-technology company; this cloud make company decision–makers focus on low PLCC and select better supplier.
ARTICLE | doi:10.20944/preprints202108.0016.v1
Subject: Social Sciences, Accounting Keywords: supplier selection; product life cycle cost; geometric averaging-weighting; penalty weighting; multiobjective linear programming; revised multichoice goal programming
Online: 2 August 2021 (11:08:56 CEST)
Supplier selection (SC) continues to be a crucial component in manufacturing procurement. Using the PLCC advantages generates revenue and lowers costs more than might be anticipated. Supplier selection (SC) product life cycle cost (SCPLCC) is an important consideration among corporations, SCPLCC problem has become associated with deciding how one supplier should be selected from possible alternatives. Past literature on this topic is limited. We try to close this gap in knowledge. In this study, we attempt to apply two types of goal programming, multiobjective linear programming and revised multichoice goal programming to develop a PLCC-based concept to solve the SCPLCC problem and construct a decision-making tool for application to a case of supply chain management in a Taiwanese light-emitting diode company in the high-tech industry. Our study main contribution Company managers can easily use the two approaches of the SCPLCC model with different parameters to solve SCPLCC model problems. Finally, we are comparing five models found RMCGP with weighted linear goal programming had an adequate effect for application to the PLCC concept for high-technology Company; this cloud makes company decision–makers focus on low PLCC and select a better supplier in sustainable supply chains development.
ARTICLE | doi:10.20944/preprints202011.0272.v1
Subject: Engineering, Automotive Engineering Keywords: fatigue life; crack initiation; resonance; shot peening; residual stress
Online: 9 November 2020 (10:18:59 CET)
The publication presents the assessment of the influence of surface treatment such as shot-peening on the fatigue life of a compressor blade exposed to resonant vibrations. As part of the work, a geometric model of the blade was developed and a numerical modal and fatigue analysis were performed. The fatigue analysis was based on the Manson-Coffin-Basquin and Ramberg-Osgood models. As part of the work, the influence of different values of residual stresses on the results of fatigue life was determined. Additionally, the location of the highest equivalent stresses was established. The obtained results of the numerical analyzes were compared with the results presented in the scientific literature. An additional aim of the study was to determine the size of the grains at various points of the blade as well as the thickness of the layer plasticized as a result of peening. The obtained results are presented in the form of tables and charts. The relationship between the location of the highest values of equivalent stresses and the thickness of the plasticized layer was determined. The explanation of the effect of shot peening on the increase in fatigue life of the blade was proposed.
ARTICLE | doi:10.20944/preprints202005.0386.v1
Subject: Keywords: remaining useful life; c-mapss; extreme learning machine; prognostic and health management; neural networks
Online: 24 May 2020 (16:24:08 CEST)
This work can be considered as a first step of designing a future competitive data-driven approach for remaining useful life prediction of aircraft engines. The proposed approach is an ensemble of serially connected extreme learning machines. The results of prediction of the first networks are scaled and fed to the next networks as an additive features to the original inputs. This feature mapping allows increasing the correlation of training inputs with their targets by holding new prior knowledge about the probable behavior of the target function. The proposed approach is evaluated under remaining useful estimation using a set of “time-varying” data retrieved from the public dataset C-MAPSS (Commercial Modular Aero Propulsion System Simulation) provided by NASA. The prediction performances are compared to basic extreme learning machine and proved the effectiveness of the proposed methodology.
ARTICLE | doi:10.20944/preprints202205.0232.v1
Subject: Engineering, Civil Engineering Keywords: concrete tensile fatigue; neural networks; Bayesian regularization; parameter assessment; fatigue life prediction
Online: 17 May 2022 (13:53:48 CEST)
The fatigue life of concrete is affected by many interwoven factors whose effect is nonlinear. Be-cause of its unique self-learning ability and strong generalization capability, the Bayesian regu-larized backpropagation neural network (BR-BPNN) is proposed to predict concrete behavior in tensile fatigue. The optimal model was determined through various combinations of network parameters. The average relative impact value (ARIV) was constructed to evaluate the correla-tion between fatigue life and its influencing parameters (maximum stress level Smax, stress ratio R, static strength f, failure probability P). ARIV results were also compared with other factor as-sessment methods (weight equation and multiple linear regression analyses). Using BR-BPNN, S-N curves were then obtained for the combinations of R=0.1, 0.2, 0.5; f=5, 6, 7MPa; P=5%, 50%, 95%. The tensile fatigue results under different testing conditions were finally compared for compatibility. It was concluded that Smax has the most significant negative effect on fatigue life; the degree of influence of R, P, and f, which positively correlate with fatigue life, decreases suc-cessively. ARIV is confirmed as a feasible way to analyze the importance of parameters and could be recommended for future applications. The tensile fatigue performance of plain concrete under different stress states (flexural tension, axial tension, splitting tension) does not differ sig-nificantly. Besides utilizing the valuable fatigue test data scattered in the literature, insights gained from this work could provide a reference for subsequent fatigue test program design and fatigue evaluation.
ARTICLE | doi:10.20944/preprints202108.0273.v1
Subject: Engineering, Mechanical Engineering Keywords: compressor blade; fatigue life; shot-peening; x-Ray diffraction; residual stresses
Online: 12 August 2021 (11:03:28 CEST)
The work presents the results of numerical fatigue analysis of a turbine engine compressor blade, taking into account the values of initial stresses resulting from surface treatment - shot-peening. The values of the residual stresses were estimated experimentally using X-ray diffraction. The paper specifies the values of the residual stresses on both sides of the blade and their reduction due to the cutting through the blade - relaxation. The obtained values of the residual stresses were used as initial stresses in the numerical fatigue analysis of the damaged compressor blade, which is subjected to resonant vibrations of known amplitude. Numerical fatigue ε-N life analysis was based on the several fatigue material models: Manson’s, Mitchell’s, Baumel-Seeger’s, Muralidharan-Manson’s, Ong’s, Roessle-Fatemi’s and Median’s, and also on the three models of cyclic hardening: Manson’s, Xianxin’s, and Fatemi’s. Because of this approach, it was possible to determine the relationship between the selection of the fatigue material ε-N model and the cyclic hardening model on the results of the numerical fatigue analysis. Additionally, the calculated results were compared with the results of experimental research, which allowed for a substantive evaluation of the obtained results. These results are of great scientific and practical importance. The problem of determining the fatigue life of blades with defects operating under resonance vibrations is one of the original tasks in the field of fracture mechanics and experimental mechanics. The results obtained are of great importance in the aviation industry and can be used during engine maintenance and inspections to assess the suitability of blades with defects in terms of the needs of further work. This aspect of engineering maintenance is of great importance from the aircraft safety point of view.
ARTICLE | doi:10.20944/preprints201804.0221.v1
Subject: Earth Sciences, Environmental Sciences Keywords: renewable energy sources; life quality; RES public acceptance; logit regression
Online: 17 April 2018 (10:18:42 CEST)
The aim of this paper is to analyze and evaluate Renewable Energy Sources (RES) usage and their contribution to citizens’ life quality. For this purpose, a survey was conducted, using a sample of 400 residents in an urban area of Attica region in Greece. The methods of Principal Components Analysis and Logit Regression were used on a dataset containing respondents’ views on various aspects of RES. Two statistical models were constructed for the identification of the main variables that are associated with RES’ usage and respondents’ opinion on their contribution to life quality. The conclusions that can be drawn show that the respondents are adequately informed about some of the RES’ types while most of them use at least one of the examined types of RES. The benefits that RES offer, were the most crucial variable in determining both respondents’ perceptions on their usage and on their contribution to life quality.
ARTICLE | doi:10.20944/preprints202008.0408.v1
Subject: Life Sciences, Virology Keywords: covid-19 antibody; coronavirus; immunoglobulin; police officer; quality of life; SARS-CoV-2
Online: 19 August 2020 (09:55:16 CEST)
The coronavirus of severe acute respiratory syndrome 2 (SARS-CoV-2), known as COVID-19, has spread rapidly around the world, leading to social detachment and the home office replacing face-to-face work. The performance of police officers faces limitations to the new requirements, while recognizing the need to ensure health and quality of life. Thus, the present study aimed to verify the panorama of the spread of COVID-19 among federal police officers by analyzing the presence of symptoms, individual protection measures (IPM), suspect screening measures (SSM) and examination for total antibodies (IgA, IgG and IgM). For this, data were collected through a questionnaire customized for this situation, blood for serological testing and measurements of clinical data from 56 federal police officers in the municipality of Marília (São Paulo, Brazil). There was no positive result in the Anti-SARS-CoV-2 serological test in any sample participant. The mean value of the Body Mass Index (27.2 ± 5.4 kg / m2) suggests overweight and obesity, in addition to the presence of hypertension in 16.1%, diabetes in 3.6%, asthma in 3.6 % and obesity by 25%, which represents an important risk of complications for COVID-19. The use of a mask is the most frequent IPM (96.4%) and most of the sample has used a cloth or home mask (90.9%). However, 47.3% have not performed the correct cleaning of the masks and 5.5% have not taken any care with mask hygiene. It can be concluded that care in relation to the professional activities of federal police to date has prevented the spread of SARS-CoV-2 and that they must be maintained or increased because risk factors, which involve quality of life and worsening of the contamination condition, were detected in the participants.
ARTICLE | doi:10.20944/preprints202012.0121.v1
Subject: Engineering, Automotive Engineering Keywords: Decarbonization Methodology; Urban Traffic; Agent-Based Transport Simulation; Life Cycle Assessment; Sustainability; Total Cost of Ownership; Charging Concepts; Conceptual Vehicle Design; Battery Electric Vehicles; Vehicle Routing Problem
Online: 6 December 2020 (18:16:16 CET)
This paper presents a new methodology to derive and analyze strategies for a fully decarbonized urban transport system which combines conceptual vehicle design, a large-scale agent-based transport simulation, operational cost analysis, and life cycle assessment for a complete urban region. The holistic approach evaluates technical feasibility, system cost, energy demand, transportation time and sustainability-related impacts of various decarbonization strategies. In contrast to previous work, the consequences of a transformation to fully decarbonized transport system scenarios are quantified across all traffic segments, considering procurement, operation and disposal. The methodology can be applied to arbitrary regions and transport systems. Here, the metropolitan region of Berlin is chosen as a demonstration case. First results are shown for a complete conversion of all traffic segments from conventional propulsion technology to battery electric vehicles. The transition of private individual traffic is analyzed regarding technical feasibility, energy demand and environmental impact. Commercial goods, municipal traffic and public transport are analyzed with respect to system cost and environmental impacts. We can show a feasible transition path for all cases with substantially lower greenhouse gas emissions. Based on current technologies and today’s cost structures our simulation shows a moderate increase in total systems cost of 13-18%.
CONCEPT PAPER | doi:10.20944/preprints202206.0094.v1
Subject: Biology, Other Keywords: : viruses; synthetic organisms; artificial life; life domains; Lithbea
Online: 7 June 2022 (04:42:38 CEST)
As synthetic/artificial life forms become more abundant and sophisticated, an increasing number of bizarre creatures - xenobots, robots, soft A-life entities, genetically engineered organisms, etc. - are invading our society. Therefore, we need to bring order to all this, to establish what is living and what is not. Here, I intend to classify all these non-natural entities and clarify their status with reference to their consideration or not as living beings, leaving the door open to an uncertain future in which perhaps we can see how "the artificial" and "the natural" merge to originate something new. To order all this "new biodiversity" and to also give entry to viruses (which are excluded of the three-domains tree of life), I propose the creation of a new domain, Lithbea (from the name: life-in-the-border entities), in which all these new human-made entities as well as the viruses will be included. Within this domain there would be two kingdoms, Virus and Humade (contraction of human-made), based on their origin, natural or human-made. A brief description of each component of Lithbea is included and the implications for society and biology of this “new biodiversity” is briefly discussed.
ARTICLE | doi:10.20944/preprints202211.0354.v1
Subject: Life Sciences, Genetics Keywords: Definition of life; self-replicators; paralife; Utility-Product paralife; abiotic life; mechanical life; complexity
Online: 18 November 2022 (10:06:48 CET)
Here I describe an overlooked form of non-biological paralife (i.e., near-life) that has been evolving on Earth for millions of years, and is currently in the final stages of transitioning into a new form of life. Any consideration of non-biological life or paralife is complicated by the fact that there is no consensus among biologists for the definition of life. This ambiguity has caused disagreement about whether subcellular reproduction systems like viruses are a form of life, despite having genomes, mutations, heritable phenotypes and system-improving evolution. To resolve this problem, I develop a definition of life that is entirely functional and independent of any of the structural idiosyncrasies of biological life on Earth: an order-generating system controlled by internally-encoded information that perpetuates itself by functioning to counteract its entropic decay. Using this definition, subcellular transposons, plasmids, and viruses are paralife because they match the definition of life in all ways except that they induce their order-generating functioning by a living host rather through their own self-sustaining production system. Using this functional definition of life, I show that utility- products (UPs) like fabricated hand tools are part of induced-reproduction systems that have features equivalent to biological genomes, mutations, heritable phenotypes, and a process of system-improving evolution. The perceived benefit of utility-products causes them to induce their reproduction by a biological life-form (humans). For these reasons, human utility products are functionally just as close to being a form of life as subcellular transposons, plasmids, and viruses, i.e., they are Utility-Product paralife (UP-parlife). I also show that some forms of UP-paralife are currently evolving into mechanical life that is capable of both self- sustaining reproduction and system-improving evolution without outside assistance. This transition requires the development of a high level of factory and/or UP automation and artificial intelligence (AI) that is capable of complex reasoning, imagination and creativity. Finally, I consider the influence of UP-life and UP-paralife on the development of the level of structural complexity in the universe, and I briefly speculate about how these non-biological forms of life and paralife will influence the expansion of scientific knowledge about the universe.
HYPOTHESIS | doi:10.20944/preprints202105.0234.v3
Subject: Physical Sciences, Applied Physics Keywords: Theory of Life; Definition of Life; Origin of Life; Electron Bifurcation; Hydrothermal Vents; Biophysics; Biological Physics
Online: 16 June 2021 (11:30:35 CEST)
The definition, origin and recreation of life remain elusive. As others have suggested, only once we put life into reductionist physical terms will we be able to solve those questions. To that end, this work proposes the phenomenon of life to be the product of two dissipative mechanisms. From them, one reinterprets extant biological life and deduces a testable scenario for its origin. The proposed theory of life allows its replication, reinterprets ecological evolution, creates new constraints on the search for life and lays the foundations for groundbreaking technologies.
ARTICLE | doi:10.20944/preprints201804.0054.v1
Subject: Earth Sciences, Other Keywords: metadata; documentation; data life-cycle; metadata life-cycle; hierarchical data
Online: 4 April 2018 (08:16:15 CEST)
The historic view of metadata as “data about data” is expanding to include data about other items that must be created, used and understood throughout the data and project life cycles. In this context, metadata might better be defined as the structured and standard part of documentation and the metadata life cycle can be described as the metadata content that is required for documentation in each phase of the project and data life cycles. This incremental approach to metadata creation is similar to the spiral model used in software development. Each phase also has distinct users and specific questions they need answers to. In many cases, the metadata life cycle involves hierarchies where latter phases have increased numbers of items. The relationships between metadata in different phases can be captured through structure in the metadata standard or through conventions for identifiers. Metadata creation and management can be streamlined and simplified by re-using metadata across many records. Many of these ideas are being used in metadata for documenting the life cycle of research projects in the Arctic.
HYPOTHESIS | doi:10.3390/sci2030073
Subject: Keywords: emergence of life; game of life; inefficiency objection; simpson’s paradox; astrobiology
Online: 18 September 2020 (00:00:00 CEST)
We address the need for a model by considering two competing theories regarding the origin of life: (i) the Metabolism First theory and (ii) the RNA World theory. We discuss two inter-related points. (I) Models are valuable tools in understanding both the processes and intricacies of the origin of life issues. (II) Insights from models also help us to evaluate the core objection to origin of life theories called “the inefficiency objection” commonly raised by proponents of both the Metabolism First theory and the RNA World theory against each other. We use Simpson’s paradox as a tool for challenging this objection. We will use models in various senses ranging from taking them as representations of reality to treating them as theories/accounts that provide heuristics for probing reality. In this paper, we will frequently use models and theories interchangeably. Additionally, we investigate Conway’s Game of Life and contrast it with our Simpson’s Paradox (SP)-based approach to emergence of life issues. Finally, we discuss some of the consequences of our view. A scientific model is testable in three senses: (i) a logical sense, (ii) a nomological sense, and (iii) a current technological sense. The SP-based model is testable in the logical sense. It is also testable nomologically. However, it is not currently feasible to test it.
CONCEPT PAPER | doi:10.20944/preprints202008.0661.v1
Subject: Biology, Other Keywords: life definition; living being definition; robot definition; living viruses; extraterrestrial life
Online: 30 August 2020 (11:33:48 CEST)
What is life, what is the difference between something that is alive and something that is not, are viruses living beings, or what would life be like elsewhere in the universe, are questions that still do not have clear-cut answers fully accepted by the scientific community. Based on the fundamental attributes of all living things, I define life as a process that takes place in very ordered organic structures and is characterized by being automatic, interactive and evolutionary. I also define a living being as an organic, highly ordered, automatic, interacting and evolutionary system, and a robot as an ordered automatic and interacting system. Based on this definition and what we know about the biology of viruses, I maintain that they should be considered as living entities. Finally, I explain why if there were life elsewhere in the universe, it would be very similar to what we know on our planet.
REVIEW | doi:10.20944/preprints202205.0199.v1
Online: 16 May 2022 (08:05:43 CEST)
Allergic diseases are becoming a major healthcare issue in many developed nations, where living environment and lifestyle are most predominantly distinct. Such differences include urbanized, industrialized living environments, overused hygiene products, antibiotics, stationary lifestyle, and fast-food based diets tend to reduce microbial diversity and lead to impared immune protection, which further increase the development of allergic diseases. In the same time, studies also showed that modulating microbiomes can ameliorate allergic symptoms. Therefore, in this paper, we aimed to review recent findings on the potential role of the human microbiome in the gastrointestinal tract, surface of skin and respiratory tract for the development of allergic diseases. Furthermore, we addressed a potential therapeutic or even preventive strategy for such allergic diseases by modulating the human microbial composition.
ARTICLE | doi:10.20944/preprints202108.0527.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: PSPS; FBSS; chronic pain; health-related quality of life; mixture models analysis; personalized pain management; chronic pain after spinal surgery
Online: 27 August 2021 (15:23:27 CEST)
Persistent Spinal Pain Syndrome Type 2 (PSPS-T2), (Failed Back Surgery Syndrome), dramatically impacts on patient quality of life, as evidenced by Health-Related Quality of Life (HRQoL) assessment tools. However, the importance of functioning, pain perception and psychological status in HRQoL can substantially vary between subjects. Our goal was to extract patient profiles based on HRQoL dimensions in a sample of PSPS-T2 patients and to identify factors associated with these profiles. Two classes were clearly identified using a mixture of mixed effect models from a clinical data set of 200 patients enrolled in “PREDIBACK”, a multicenter observational prospective study including PSPS-T2 patients with 1-year follow-up. We observed that HRQoL was more impacted by functional disability for first class patients (n=136) and by pain perception for second class patients (n=62). Males that perceive their work as physical were more impacted by disability than pain intensity. Lower education level, lack of adaptive coping strategies and higher pain intensity were significantly associated with HRQoL being more impacted by pain perception. The identification of such classes allows for a better understanding of HRQoL dimensions and opens the gate towards optimized health-related quality of life evaluation and personalized pain management.
ARTICLE | doi:10.20944/preprints202008.0491.v1
Subject: Arts & Humanities, Religious Studies Keywords: folk beliefs; ancestor worshiping belief; spiritual life; beliefs and religion life; Vietnamese people; Vietnam today
Online: 22 August 2020 (05:03:32 CEST)
In all forms of folk beliefs, ancestor worship is a universal traditional belief form of the Vietnamese people. As a Vietnamese people, “everyone worships their ancestors, everyone worships their parents and grandparent”. Ancestor worship is a common belief in the whole country. It is a belief that expresses the deeply humanistic spirit of the Vietnamese people and has great values in human life. So, what is the nature of ancestor worship? What is the values of ancestor worship in life? And in the context of globalization, how has this the belief changed? This study focuses on analyzing the above contents, thereby highlighting the value of this belief in the spiritual life of Vietnamese people; to point out the positive and negative changes of this belief in the current period; from that, take the right measures to bring into play the positive and limit the negative side of those changes in the spiritual life of Vietnamese people.
ARTICLE | doi:10.20944/preprints202210.0033.v1
Subject: Behavioral Sciences, Clinical Psychology Keywords: emotional-intelligence; life-skills; vulnerable-populations
Online: 5 October 2022 (10:55:00 CEST)
Children living in residential care homes (RCH) often present conditions of abandonment due to separation, abuse and mistreatment; circumstances that are detrimental to proper emotional development, resulting in poor self-confidence, aggressive behaviors, low self-esteem, anxiety, among other developmental problems. Additionally, pandemic lockdown hinders access to mental health services for RCH service providers, and limits children to external mental health support and resources. The objective of this study was to design and evaluate the effectiveness of a remote-applied Emotional-Intelligence-based intervention program (RA-EIBI) for children living in RCH during pandemic lockdown. A non-parametric pre-test, treatment, post-test comparative design was used to evaluate effectiveness of the intervention program. Seven children living in RCH during pandemic lockdown were initially assessed using Evaluation of Neurological Soft Signs, and Empathy Quotient (EQ-I) to estimate emotional intelligence quotient. A 10 session RA-EIBI program was designed and applied to the children after initial assessment, and a final evaluation was conducted to perform related samples comparisons. Results shown a non-significant mean increase of intrapersonal, interpersonal, stress management, adaptability, and emotional state, all emotional intelligence-related skills. A RA-EIBI program is an accessible resource for RCH, and children living under this condition. EI skills were maintained along the social isolation period due to COVID-19. Followup of emotional conditions of children demonstrated an improvement in self-perceived well-being.
ARTICLE | doi:10.20944/preprints202209.0297.v1
Online: 20 September 2022 (07:15:52 CEST)
Abstract Despite the lightning-fast advances in the management of SARS-CoV after 2 years of pandemic, COVID-19 continues to pose a challenge for fragile patients, who could benefit from early administration of monoclonal antibodies (mAbs) to reduce the risk of severe disease progression. We conducted a prospective study to evaluate effectiveness of mAbs against SARS-CoV-2 among patients at risk for severe disease progression, namely elderly and those with comorbidities, before the omicron variant surge. Patients were treated with either casirivimab/imdevimab, sotrovimab, and bamlanivimab/etesevimab. The rates and risk factos for clinical worsening, hospitalization, ICU admission and death (unfavourable outcomes) were evaluated. A stratified analysis according to the presence of SARS-CoV-2 IgG was also performed. Among 185 included patients, we showed low rates of unfavorable outcomes (9.2%), which were more frequent in patients with chronic kidney disease (aOR: 10.44, 95CI: 1.73-63.03; p<0.05) and basal D-dimer serum concentrations >600 ng/ml (aOR 21.74, 95CI: 1.18-397.70; p<0.05). Patients with negative SARS-CoV-2 serology at baseline showed higher C-reactive protein values compared with patients with positive serology (p <0.05) and showed a trend toward a higher admission rate to SICU and ICU compared with patients with positive serology. Our results thus showed, in a real-life setting, the efficacy of mAbs against SARS-CoV-2 before Omicron surge when the available mabs become not effective.
SHORT NOTE | doi:10.20944/preprints202009.0401.v2
Online: 26 July 2022 (08:51:22 CEST)
The world’s human population is reaching record longevities. Consequently, our societies are experiencing the impacts of prolonged longevity, such as increased retirement age. A major hypothesised influence on ageing patterns is resource limitation, formalised under calorie restriction theory. This theory predicts extended organismal longevity due to reduced calorie intake without malnutrition. However, several challenges face current calorie restriction (CR) research and, although several attempts have been made to overcome these challenges, there is still a lack of holistic understanding of how CR shapes organismal vitality. Here, we conduct a literature review of 222 CR peer-reviewed publications to summarise the state-of-the-art in the field. We use this summary to highlight challenges of CR research in our understanding of its impacts on longevity. Our review demonstrates that experimental research in this field is biased towards short-lived species (98.2% of studies examine species with <5 years of mean life expectancy) and lacks realism in key areas, such as stochastic environments or interactions with other environmental drivers such as temperature. We argue that only by considering a range of short- and long-lived species and by taking more realistic approaches can the impacts of CR on longevity be examined and validated in natural settings. We conclude by proposing experimental designs and study species that will allow the discipline to gain a much-needed understanding of how restricting caloric intake affects long-lived species in realistic settings. Through incorporating more experimental realism, we anticipate crucial insights that will ultimately shape the myriad of socio-bio-economic impacts of senescence in humans and other species across the Tree of Life.
ARTICLE | doi:10.20944/preprints202108.0470.v1
Online: 24 August 2021 (13:59:30 CEST)
Background: The tsunami and earthquake occurred in 1927 and 2018 made life quality of Da’a Tribe women in refugee camps was affected by violence. It affects on women reproductive health in various aspects of life as high maternal mortality rate of 450 per 100 thousand live births and half of women victims of natural disasters have reproductive health problems such as anemia and malnutrition during pregnancy. The study objective is to explore the health quality of women related to the couple violence during the humanitarian crisis at refugees’ camps. Method: The population was 798 cases of violence. The 90 samples were selected by simple random sampling and calculated by Slovin method. Data analysis was done by descriptive qualitative and cross tabulation. The research location was Palu City. Results: The research findings showed that health quality of Da’a Tribe women after the couple violence is influenced by three factors, namely economic by 40%, psychological by 7%, violence during pregnancy 59.3%. Conclusion: Social life and women violence handling can be done by symbolizing the threat of criminal law for male perpetrators in accordance with applicable laws in Indonesia and improving the life quality of population, especially women in education and skills through empowering the family economy and increasing gender equality justice.
Subject: Physical Sciences, Acoustics Keywords: cosmology, life, superfluid quantum space, consciousness.
Online: 15 April 2021 (13:38:05 CEST)
The evolution of life on the planet Earth is happening primarily in the universe and secondary on the Earth. We will examine in this article evolution of life as the cosmic phenomena. In our model multidimensional time-invariant superfluid quantum space that is the fundamental arena of the universe and represents about 95% of the energy in the universe has stable entropy. The increase of entropy happens only by about 5% of the energy in the universe that is in the form of matter. The evolution of life in our model is a process of matter organization into living systems that tends to develop towards the constant entropy of the time-invariant multidimensional quantum space. This process runs in the entire universe. The development of life into intelligent organisms is the universal process running throughout the entire universe.
REVIEW | doi:10.20944/preprints201711.0176.v1
Subject: Life Sciences, Molecular Biology Keywords: mitochondria; proteolysis; protein half-life; ubiquitin
Online: 27 November 2017 (09:18:27 CET)
The mitochondrial network is a dynamic organization within eukaryotic cells that participates in a variety of essential cellular processes, such as ATP synthesis, central metabolism, apoptosis and inflammation. The mitochondrial network is balanced between rates of fusion and fission that respond to pathophysiologic signals to coordinate appropriate mitochondrial processes. Mitochondrial fusion and fission are regulated by proteins that either reside or translocate to the inner or outer mitochondrial membranes or are soluble in the inter-membrane space. Mitochondrial fission and fusion are performed by GTPases on the outer and inner mitochondrial membranes with the assistance of other mitochondrial proteins. Due to the essential nature of mitochondrial function for cellular homeostasis regulation of mitochondrial dynamics is under strict control. Some of the mechanisms used to regulate the function of these proteins are post-translational proteolysis and/or turnover and this review will discuss these mechanisms required for correct mitochondrial network organization.
Subject: Keywords: clay; mica; biotite; muscovite; origin of life; abiogenesis; mechanical energy; work; wet-dry
Online: 5 November 2020 (10:43:44 CET)
This paper presents a hypothesis about the origins of life in a clay mineral, starting with the earliest molecules, continuing through the increasing complexity of the development, in neighboring clay niches, of “Metabolism First,” “RNA World,” and other necessary components of life, to the encapsulation by membranes of the components in the niches, to the interaction and fusion of these membrane-bound protocells, resulting finally in a living cell, capable of reproduction and evolution. Biotite (black mica) in micaceous clay is the proposed site for this origin of life. Mechanical energy of moving biotite sheets provides one endless source of energy. Potassium ions between biotite sheets would be the source of the high intracellular potassium ion concentrations in all living cells.
ARTICLE | doi:10.20944/preprints201807.0024.v1
Subject: Social Sciences, Sociology Keywords: contextual risk factors; gender; individual risk factors; life-work interference; self-employed; wellbeing; work-life interference
Online: 3 July 2018 (05:56:36 CEST)
This study explores individual and contextual risk factors for the onset of work interfering with private life (WIL) and private life interfering with work (LIW) among self-employed men and women across European countries. It also studies the relationship between interference (LIW and WIL) and wellbeing among self-employed men and women and the effect of macro level risk factors. Data from the fifth round of European Working Conditions Survey was utilized and a sample of self-employed men and women with active businesses was extracted. Applying multilevel regressions, results show that though business characteristics are important for level of WIL, time demand is the most evident risk factor for WIL and LIW. There is a relationship between wellbeing and WIL and LIW respectively, and time demands is the most important factor in this relationship. Gender equality on the labor market did not relate to level of interference, nor did it mediate the relationship between interference and wellbeing. However, the main and most important risk factor for experiencing WIL and LIW and for how interference relate to wellbeing is gender relation processes in work and life, both on individual and contextual level.
ARTICLE | doi:10.20944/preprints202012.0540.v1
Subject: Social Sciences, Accounting Keywords: work-life balance; work-life enrichment; outside-of-work activity; sustainable human capital development; COVID-19 pandemic
Online: 21 December 2020 (16:04:46 CET)
Nowadays, the development of civilization requires a vision of balancing the interests of employees and employers in the sphere of work as never before. Work-life balance is directly linked to social sustainability. The aim of this article is to analyse various dimensions of mutual enrichment of the professional and private life of an individual and to describe how positive experiences in professional and non-professional life influence the improvement of satisfaction, health and achievements, thus enabling the sustainable development of the individual. The conducted research was of a qualitative nature. Thematic exploration was used to analyse the findings of 34 in-depth interviews with experienced HR managers and employees at various levels of enterprises in Poland. The research shows that the work and personal life of the respondents interact, complement, and enrich in different ways, depending on the stage of the employee’s life. Habits developed by practicing a specific sport discipline or other type of hobby are helpful in the effective implementation of professional tasks. Also, non-professional interests, including communing with culture and art have a positive impact on professional activities. On the other hand, the respondents emphasized that thanks to their professional activities, specific to the type of work they perform, they are sometimes more extroverted, meticulous, organized and consistent when performing activities outside of work and in other aspects of private life.
ARTICLE | doi:10.20944/preprints202108.0545.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Composite score; Machine learning; PSPS; Failed Back Surgery Syndrome (FBSS); Chronic pain; Pain Intensity; Quality of Life; Pain Mapping; Pain Surface; Functional Capacity; Psychological Distress; Anxiety and Depression
Online: 30 August 2021 (13:04:51 CEST)
The multidimensionality of chronic pain forces us to look beyond isolated pain assessment such as pain intensity, which does not consider multiple key parameters, particularly in patients suffering from post-operative Persistent Spinal Pain Syndrome (PSPS-T2). Our ambition was to provide a novel Multi-dimensional Clinical Response Index (MCRI), including not only pain intensity but also functional capacity, anxiety-depression, quality of life and objective quantitative pain mapping assessments, the objective being to capture patient condition instantaneously, using machine learning techniques. Two hundred PSPS-T2 patients were enrolled in a real-life observational prospective PREDIBACK study with 12-month follow-up and received various treatments. From a multitude of questionnaires/scores, specific items were combined using exploratory factor analyses to create an optimally accurate MCRI; as a single composite index, using pairwise correlations between measurements, it appeared to better represent all pain dimensions than any other classical score. It appeared to be the best compromise among all existing indexes, showing the highest sensitivity/specificity related to Patient Global Impression of Change (PGIC). Novel composite indexes could help to refine pain assessment by changing the physician’s perception of patient condition on the basis of objective and holistic metrics, and by providing new insights to therapy efficacy/patient outcome assessments, before ultimately being adapted to other pathologies.
ARTICLE | doi:10.20944/preprints202207.0311.v1
Subject: Life Sciences, Endocrinology & Metabolomics Keywords: glucose; cortisol; corticosterone; stress; early life adversity
Online: 21 July 2022 (07:53:13 CEST)
External stressors strongly increase cardiovascular activity and induce metabolic changes that ensure the availability of glucose and oxygen as part of a co-ordinated stress response. Exposure to stress during early life appears to have an exaggerated long-term effect on this response, leading to an increased risk or cardiometabolic disorders. Here we demonstrate that acute stress induced glucose release is impacted by the early life environment in rodent maternal deprivation and early-life infection models and this was validated in our EpiPath human early-life adversity cohort. In all three models differences in baseline blood glucose levels after ELA exposure were sex dependent. The human ELA model showed higher levels of basal glucose in females, similar to the mouse infection and rat maternal deprivation models. We anticipated that the stress induced glucose rise would be a GC dependent process. However, the kinetics of stress-induced glucose release, peaking 15-28 minutes before cortisol suggest that it is a GC-independent process. We confirmed this by administering an escalating dose of cortisol to a health human cohort, and the inability of an intravenous GC bolus induce a glucose rise in man confirms that it is a rapid, GC independent, process.In conclusion, we provide a novel perspective on the mechanisms behind stress related metabolic changes and highlights the importance of collecting early life data as a measure to understand an individual’s metabolic status in a better light.
HYPOTHESIS | doi:10.20944/preprints202202.0033.v1
Online: 2 February 2022 (12:55:42 CET)
Reducing overall food intake or lowering the proportion of protein relative to other macronutrients, can extend lifespan in diverse organisms. A number of mechanistic theories have been developed to explain this phenomenon, mostly assuming that the molecules connecting diet to lifespan are evolutionarily conserved. A recent study using Drosophila melanogaster females has pinpointed a single essential micronutrient that can explain how lifespan is changed by dietary restriction. Here, we propose a likely mechanism for this observation, which involves a trade-off between lifespan and reproduction, but in a manner that is conditional on the dietary supply of an essential micronutrient – a sterol. Importantly, these observations argue against previous evolutionary theories that rely on constitutive resource reallocation or damage directly inflicted by reproduction. Instead, they are compatible with a model in which the inverse relationship between lifespan and food level is caused by the consumer suffering from varying degrees of malnutrition when maintained on lab food. The data also indicate that animals on different lab foods may suffer from different nutritional imbalances and that the mechanisms by which dietary restriction benefits the lifespan of different species may vary. This means that translating the mechanistic findings from lab animals to humans will not be simple and should be interpreted in light of the range of challenges that have shaped each organism’s lifespan in the wild and the composition of the natural diets they would feed on.
ARTICLE | doi:10.20944/preprints202106.0591.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Adsorption; Desorption; Dissipation; Herbicide half-life; Leaching.
Online: 23 June 2021 (16:02:59 CEST)
Chemical weed control using herbicide glyphosate to manage emerged weeds is an important production practice in Florida citrus. Despite the extensive use of glyphosate in citrus orchards, very limited information is available on its environmental fate and behavior in Florida soils that are predominantly sandy in nature. Hence, the study's objective was to understand the adsorption-desorption, dissipation dynamics, and vertical movement or leaching of glyphosate in sandy soils in citrus orchards. Laboratory, field, and greenhouse experiments were conducted at Southwest Florida Research and Education Center in Immokalee, Florida. The adsorption-desorption behavior of glyphosate in the soils from three major citrus production areas in Florida was studied utilizing a batch equilibrium method. The dissipation of glyphosate was tracked in the field following its application at the rate of 4.20 kg ae ha-1. Soil leaching columns in greenhouse conditions were used to study the vertical movement of glyphosate. The results suggest that glyphosate has a relatively lower range of adsorption or binding (Kads = 14.28 to 30.88) in the tested soil types. The field dissipation half-life (DT50) of glyphosate from surface soil was found to be 26 days. Glyphosate moved vertically or leached into the soil profile, up to 40 cm in the soil column, when analyzed 40 days after herbicide application. The primary degradation product of glyphosate, i.e., aminomethyl phosphonic acid (AMPA), was also detected up to the depth of 30 cm below the soil surface, indicating the presence of microbial metabolism of glyphosate in the soil.
ARTICLE | doi:10.20944/preprints202106.0567.v1
Subject: Medicine & Pharmacology, Allergology Keywords: multimedia; self-care; quality of life; enterostomy
Online: 23 June 2021 (11:08:14 CEST)
(1)Background: This report was an effective evaluation of using multimedia educational program for self-care and quality of life in patients with a stoma at postoperative and established a simple threshold for enterostomy self-care skills.(2)Methods:108 patients with enterostomy were randomly assigned to receive either the intervention multimedia education program (including information about preparation for enterostomy care, cleaning method, manual bag replacement steps and precautions). The primary outcome was self-care ability and quality of life (defined as overall enterostomy self-care ability and overall quality of life), which was assessed at 2 weeks after intervention via an interview.(3)Results: Compared with those who in the conventional stoma education program, patients received the multimedia education program significantly improved their overall self-care ability and quality of life in statistically. The threshold of the enterostomy self-care skill scale was 20 points, and its corresponding sensitivity was 77.8%, and the specificity was 75.7%.(4)Conclusions: According to our study, the multimedia education program could enhance self-care ability of home care and quality of life in patients with enterostomy.
ARTICLE | doi:10.20944/preprints202103.0188.v1
Subject: Medicine & Pharmacology, Allergology Keywords: disability; quality of life; cerebral palsy; surveillance
Online: 5 March 2021 (11:51:51 CET)
Secondary and tertiary prevention strategies targeting people with disabilities to improve their health and wellbeing is important. In Sweden, >95% of all children with cerebral palsy (CP) participate in a follow-up program, where one of the goals is the prevention of hip dislocations. We reviewed the incidence of hip dislocations from 2010 to 2019 and the number of children who underwent different types of hip surgeries. The number of hip dislocations was reduced from 8.8% before introduction of the program to 0.3-0.4% up to 2015, followed by a gradual increase to 0.8% in 2019. The proportion of children who underwent adductor-psoas lengthening as their primary preventive surgery decreased from 50% in 2017 to 37% in 2019 with a corresponding increase of children undergoing femoral osteotomy, indicating more children underwent surgery at a later stage. Reasons for the increased number of children with hip dislocation may be that more children have moved to Sweden in recent years without corresponding compensation in health care resources and increased waiting times for surgery due to, among other things, a shortage of nurses. The results highlight the importance of constantly monitoring follow-up programs.
ARTICLE | doi:10.20944/preprints202011.0412.v1
Subject: Biology, Anatomy & Morphology Keywords: Process; ontological category; life concept; essential feature
Online: 16 November 2020 (10:49:11 CET)
Although increasing knowledge about biological systems has advanced exponentially in recent decades, it is surprising to realize that the very definition of Life keeps presenting theoretical challenges. Even if several lines of reasoning seek to identify the essence of life phenomenon, most of these thoughts contain fundamental problem in their basic conceptual structure. Most concepts fail to identify necessary and sufficient features to define life. Here, we analyzed the main conceptual framework regarding theoretical aspects supporting life concepts, such as (i) the physical, (ii) the cellular and (iii) the molecular approaches. Based on ontological analysis, we propose that Life should not be positioned under the ontological category of Matter. Yet, life should be better understood under the top-level ontology of “Process”. Exercising an epistemological approach, we propose that the essential characteristic pervading each and every living being is the presence of organic codes. Therefore, we explore theories in biosemiotics in order to propose a clear concept of life as a macrocode composed by multiple inter-related coding layers. Therefore, we suggest a clear distinction between the concept of life and living beings, a distinction that is not evident in theoretical terms. From the proposed concept, we suggest that the evolutionary process is a fundamental characteristic for life’s maintenance but not to its definition. The current proposition opens a fertile field of debate in astrobiology, biosemiotics and robotics.
REVIEW | doi:10.20944/preprints202009.0086.v1
Online: 4 September 2020 (07:31:34 CEST)
Space missions have always assumed that the risk of spacecraft malfunction far outweighs the risk of human system failure. This assumption breaks down for longer duration exploration missions and exposes vulnerabilities in space medical system. Space agencies can no longer buy down the majority of human system risk through the crew member selection process and emergency re-supply or evacuation. No mature medical solutions exist to close the risk gap. With recent advances in biotechnology, there is promise in augmenting a space pharmacy with a biologically-based space foundry for on-demand manufacturing of high-value medical products. Here we review the challenges and opportunities of molecular pharming, the production of pharmaceuticals in plants, as the basis of a space medical foundry to close the risk gap in current space medical systems. Plants have long been considered an important life support object in space and can now also be viewed as programmable factories in space. Advances in molecular pharming-based space foundries will have widespread application in promoting simple and accessible pharmaceutical manufacturing on Earth.
SHORT NOTE | doi:10.20944/preprints202005.0017.v1
Online: 2 May 2020 (15:54:19 CEST)
Maximum entropy production principle (MEPP) has been formulated in the mid-twentieth century, and today it has acquired the status of an important principle of science, which is extremely effective in considering various non-equilibrium problems. In this study, for the first time, definition of life is based on an easily measurable physical quantity that is entropy production. Life and evolution are discussed from the point of view of MEPP and the Universe, but not a human
REVIEW | doi:10.20944/preprints201911.0201.v1
Subject: Behavioral Sciences, Clinical Psychology Keywords: Iran; sanctions; mental health; quality of life
Online: 17 November 2019 (10:53:30 CET)
In order to synchronize foreign policies of governments, firm actions in the form of economic sanctions have long been employed by western countries. Those countries that tend to have independent views and policies are made to undergo economic adversity to fall in line. But the hardest hit by these coercive actions are the ordinary citizens who have to endure immense difficulty with social and economic issues not to mention the human rights violations. This paper provides a review regarding the effect of economic sanctions on mental health and quality of life of Iranian citizens based on data available from Iran post-sanctions. From 2012 stronger sanctions have been implemented on Iran as its nuclear program failed to draw faith in terms of its peaceful execution. Evidence have pointed out that economic sanctions imposed by western countries have a detrimental and destructive effect on the health of individual Iranians and they violated some basic human rights.
Subject: Medicine & Pharmacology, Gastroenterology Keywords: quality of life; celiac disease; parents; caregivers
Online: 20 September 2019 (19:04:08 CEST)
Celiac disease (CD) is an autoimmune disorder triggered by the ingestion of gluten and affects approximately 1% of the global population. Currently, the only treatment available is lifelong strict adherence to a gluten-free diet (GFD). Chronic diseases such as CD affect patients and their family members’ quality of life (QoL); particularly parents and caregivers who play an essential role in the child’s care and treatment. A higher level of psychological distress has been found in the parents of children with chronic ailments due to limited control over the child’s daily activities and the child’s illness. In this context, the validation of a specific questionnaire of QoL is a valuable tool to evaluate the difficulties faced by parents or caregivers of children with this chronic illness. A specific questionnaire for this population can elucidate the reasons for stress in their daily lives as well as the physical, mental, emotional, and social impact caused by CD. Therefore, this study aimed to develop and validate a specific questionnaire to evaluate the QoL of parents and caregivers of children and adolescents with CD. The study was developed in six steps: (i) development of the CD parent/caregiver QoL questionnaire (CDPC-QoL); (ii) subjective evaluation; (iii) validation of the questionnaire by the Delphi method; (iv) evaluation of the internal consistency and reproducibility of the CDPC-QoL; (v) application of the questionnaire to Brazilian CD parents or caregivers; and (vi) statistical analysis. Overall results showed that a higher family income resulted in a higher score of the worries domain. In addition, having another illness besides CD decreased the QoL (except in the worries domain). The other variables studied did not present a statistically significant impact on the QoL, which was shown to be low in all aspects. Knowledge of the QoL is important to help implement effective strategies to improve celiac patients’ quality of life and reduce their physical, emotional, and social burden.
HYPOTHESIS | doi:10.20944/preprints201811.0564.v2
Online: 27 February 2019 (11:32:02 CET)
Current cellular facts allow us to follow the link from chemical to biochemical metabolites, from the ancient to the modern world. In this context, the "RNA world" hypothesis proposes that early in the evolution of life, the ribozyme was responsible for the storage and transfer of genetic information and for the catalysis of biochemical reactions. Accordingly, the hammerhead ribozyme (HHR) and the hairpin ribozyme, belong to a family of endonucleolytic RNAs performing self-cleavage that might occur during replication. Furthermore, regarding the ultraconserved occurrence of HHR in several genomes of modern organisms (from mammals to small parasites and elsewhere), these small ribozymes have been regarded as living fossils of a primitive RNA world. They fold into 3D structures that generally require long-range intramolecular interactions to adopt the catalytically active conformation under specific physicochemical conditions. By studying viroids as plausible remains of ancient RNA, we recently demonstrated that they replicate in non-specific hosts, emphasizing their adaptability to different environments, which enhanced their survival probability over the ages. All these results exemplify ubiquitously features of life. Those are the versatility and efficiency of small RNAs, viroids and ribozymes, as well as their diversity and adaptability to various extreme conditions. All these traits must have originated in early life to generate novel RNA populations.
ARTICLE | doi:10.20944/preprints201805.0388.v1
Online: 28 May 2018 (08:48:11 CEST)
Understanding the reproductive patterns and strategies of a species is an important step in establishing the species’ life history. Campostoma oligolepis, the Largescale Stoneroller, is a species that has received little attention in the 90 years since it was first identified, and the work that has been done has been localized in the American Midwest. Collections of C. oligolepis were made monthly from the Flint River in Madison County in northern Alabama, USA, from March, 2014, to September, 2015. A total of 768 fish were collected over the collection period including 492 adults, 268 females and 224 males. We found strong evidence that the peak spawning time for C. oligolepis in the Flint River is March and April. Ovarian maturation, gonadosomatic index for both sexes, and monthly clutch size all support this conclusion. Two unexpected features were found. The first is how few females of mature size were found to carry either oocytes or a clutch except in the peak observed reproductive month of April, 2014. The second unusual feature is the prevalence of asymmetric ovaries, with the left the larger if a difference exists. Campostoma oligolepis may have unusually strong inter-annual responses to abiotic factors such as water temperature and river discharge.
ARTICLE | doi:10.20944/preprints201803.0100.v1
Online: 14 March 2018 (07:50:44 CET)
Nietzsche is almost always regarded as one of the thinkers who advocate extreme individualism, totally indifferent to or exclusively polemical towards the public human dimension. While this is very difficult to contradict, if we read his texts carefully we can see how his constant celebration of the individual runs parallel to an acute awareness of living in a new era, which he defined as ‘the century of the multitude and the masses’. The herd, conformism, mediocrity, public opinion: a civilisation in which community attempts suffocate all individual inspiration, and which therefore seems to row in the opposite direction. Although Nietzsche often uses collective life merely as a negative pole for more effectively emphasising the individual, his provocative words—pushed to the limits of the inexorable victory of the herd and of the paradoxical impossibility of all that is ‘public’—offer us a direct testimony of the tragic way of life of the man of his time. This provides us with an extremely clear and interesting phenomenological cross-section of the social sphere, as well as a very finely tuned and valuable seismograph for the continual monitoring of our everyday coexistence with and perception of the constantly incumbent dangers of its degeneration.
ARTICLE | doi:10.20944/preprints201608.0122.v1
Subject: Medicine & Pharmacology, Other Keywords: oral health; quality of life; postmenopausal women
Online: 13 August 2016 (03:14:09 CEST)
Interrelationships between traditional dental variables are becoming more evident in far reaching aspects of life such as psychosocial interaction, self-esteem, overall health and even occupational performance. This study compares quality of life (QoL) in postmenopausal women (PMW) with poor oral health (POH) with QoL in PMW with good oral health. 200 randomly recruited PMW received a dental evaluation and completed Utian Quality of Life Survey. The participants were divided into POH and healthy groups based on dental exam. Mean scores were calculated for each QoL item, domain and the overall summary score. For each of the four parameters for periodontitis diagnosis, periodontitis patients’ QoL outcomes were compared to those of healthy patients using T-test with threshold of significance at p<0.05. QoL in all fields measured were significantly poorer in the POH compared to the healthy patients, occupational (19.95±5.35vs. 27.56±6.13), health (18.02±8.23 vs. 26.59 ±6.45), emotional (15.68±10.22vs. 21.15±9.15), sexual (6.2±5.98vs. 10.02±5.35), and total score (60.21±25.85 vs. 84.26±22.35). This study finds that PMW with POH, report significantly poorer quality of life. Clinicians caring for PMW should be aware of that oral health impacts QoL and make appropriate referral decisions for patients’ dental care. Keywords: Quality of Life, Oral Health, Post-menopause, Women
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Bioregenerative life support; closed ecological life support; in-situ resource utilization; lunar industrial ecology; 3D bioprinting; gene editing
Online: 28 June 2021 (15:23:39 CEST)
In this review, we explore a broad-based view of technologies for supporting human activities on the Moon. Primarily, we assess the state of life support systems technology beginning with physicochemical processes, waste processing, bioregenerative methods, food production systems and the robotics and advanced biological technologies that support the latter. We observe that the Moon possesses in-situ resources but that these resources are of limited value in CELSS – indeed, CELSS technology is most mature in recycling water and oxygen, the two resources that are abundant on the Moon. This places a premium on developing CELSS that recycles other elements that are rarified on the Moon including C and N in particular but also other elements such as P, S and K which might be challenging to extract from local resources. Although we focus on closed loop ecological life support systems, we also consider related technologies that involve the application of biological organisms to bioregenerative medical technologies and bioregenerative approaches to industrial activity on the Moon as potential future developments.
Subject: Life Sciences, Molecular Biology Keywords: origin of life; origins of life; mechanical energy; work; entropic forces; mica; biotite; Muscovite; wet/dry cycles; clay
Online: 29 April 2019 (07:51:38 CEST)
Forces and mechanical energy are prevalent in living cells. This may be because forces and mechanical energy preceded chemical energy at life’s origins. Mechanical energy is more readily available in non-living systems than the various other forms of energy used by living systems. Two possible prebiotic environments that might have provided mechanical energy are hot pools that experience wet/dry cycles and mica sheets as they move, open and shut, as heat pumps or in response to water movements.
ESSAY | doi:10.3390/sci2020019
Subject: Keywords: origin of life; origins of life; mechanical energy; mechanochemistry; work; entropic forces; mica; biotite; Muscovite; wet/dry cycles; clay
Online: 25 March 2020 (00:00:00 CET)
Mechanical forces and mechanical energy are prevalent in living cells. This may be because mechanical forces and mechanical energy preceded chemical energy at life’s origins. Mechanical energy is more readily available in non-living systems than the various forms of chemical energy used by living systems. Two possible prebiotic environments that might have provided mechanical energy are hot pools that experience wet/dry cycles and mica sheets as they move, open and shut, as heat pumps or in response to water movements.
ARTICLE | doi:10.20944/preprints202203.0024.v1
Subject: Social Sciences, Other Keywords: multi scale; quality of life; wavelets; mathematical models
Online: 1 March 2022 (13:32:59 CET)
The present paper is concerned with the study of the quality of life index. Such an index has become an important index for measuring the well-being of individuals. However, the quality of life index is always a subjective, intangible, and often hard to quantify with precision due to the lack of quantitative models dealing with. The main goal of the present paper is thus to propose a mathematical, quantitative model for the measurement of a quality of life index. The main novelty is firstly the construction of a wavelet dynamic multiscale model to quantify and investigate the effect of time scale on the quality of life index measuring. The proposed procedure is acted empirically on a sample corresponding to Saudi Arabia as a case of study during the period from 2003 to 2020 as part of the 2030-vision plan. Saudi Arabia has implemented the so-called 2030-vision plan where the quality of life improvement is one of the main goals to be attempted. The findings show that wavelets are capable to localize the time-wise behavior of the index contrarily to classical studies which estimate a global view of the index. Moreover, the study shows the link between the quality of life behavior and many other indices.
ARTICLE | doi:10.20944/preprints202202.0205.v1
Subject: Behavioral Sciences, General Psychology Keywords: taste; smell; quality of life; sensitivity; threshold; QUEST
Online: 17 February 2022 (10:00:37 CET)
Taste and smell function decline with age, with robust impairment in the very old. Much less is known about taste and smell function in young and middle old. We investigated taste and smell sensitivity via thresholds in a sub-sample of the NutriAct Family Study (NFS), the NFS Examinations cohort (NFSE; N=251, age M=62.5 years). We examined different aspects relating to taste and smell function: the degree to which taste and smell sensitivity relate to another and to taste and smell preferences, the role of gender and age, as well as effects on Quality of Life (QOL). Taste thresholds were highly correlated but no correlation was observed between taste and smell thresholds and between thresholds and preference. Women were more sensitive for both taste and smell than men. We found no effect of age on sensitivity and no effect of sensitivity on QoL. All null-findings were corroborated with Bayesian statistics providing evidence for the null hypotheses. Together our results indicate the independence of taste and smell despite their overlap during sensorial experiences. We found no evidence for age-related sensory decline, which could be due to our sample´s characteristics of non-clinical volunteers with good dental health and 93% non-smokers.
ARTICLE | doi:10.20944/preprints202109.0397.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: Hypertension management; Complications of cardiovascular; Quality of Life
Online: 23 September 2021 (09:03:57 CEST)
The aim of this study as to determine the relationship between the factors of demography, comor-bidity, medication, lifestyle, and access to health services related to the QoL of people with hy-pertension and its complications in Sleman Regency, Yogyakarta. The study was conducted in a cross-sectional manner using data from Sleman HDSS (Health and Demographic Surveillance System) from 2015 to 2018 in cycles 3 and 2 with the inclusion criteria of hypertensive patients and their complications aged 25 years or older obtained by using a total sampling of 532 people. Measurement of QoL using Short Form 12v2 2a and 2b questionnaires presented in the Physical Component Summary (PCS) and Mental Component Summary (MCS). Data analysis using Mann-Whitney test and Kruskal Wallis test. The results showed factors related to the QoL in PCS were variables of gender, age, diagnosis of hypertension and its complications, the presence of comorbidities, fatty foods, drug consumption in the last two weeks, while factors related to the mental component (MCS) were education and occupation seen from the p-value <0.05. QoL with hypertension and its complications influence and decrease the physical than the patient's mental condition.
Subject: Engineering, Automotive Engineering Keywords: Pyrolysis; Life cycle assessment; Techno-economic assessment; sludge
Online: 26 July 2021 (10:06:50 CEST)
The increasing amount of municipal sludge in China requires safe and effective management to protect human health and ensure environmental sustainability. Pyrolysis is a thermochemical process that that decompose organic matter at elevated temperature and under anaerobic conditions, and it has attracted an increasing attention in sludge treatment in the recent years. However, comprehensive environmental and economic assessment of sludge pyrolysis in China's context is rare, due to the small quantities of full-scale sludge pyrolysis plant. In this paper, we applied our design and operation parameters of full-scale sludge pyrolysis plants to generate the material and energy consumptions of the pyrolysis system under various of conditions, including sludge organic content and moisture content, system size, system energy distribution, and whether or not heat substitution is applied. Life cycle assessment and techno-economic assessment were then applied to investigate the environmental and economic performance of the system Our results demonstrate the significant environmental and economic impacts associated with sludge properties and system size. Generally, sludge with higher organic content and lower moisture content requires less natural gas consumption, which leads to a simultaneous improvement of the system environmental and economic performance. The system economic performance is more sensitive to the system size, and centralized sludge handling using a larger pyrolysis is more economic favorable. In the most ideal case, the average global warming potential and minimum sludge handling price of sludge pyrolysis could be as low as -32.5 kg CO2-Eq/t DS and 188.8 $/t DS, respectively. Based on these results, we discussed the pathways that could be taken to further optimize the environmental and economic performances of the pyrolysis system.
ARTICLE | doi:10.20944/preprints202103.0554.v2
Subject: Arts & Humanities, Anthropology & Ethnography Keywords: philosophy of science; information; artificial life; scales; causality
Online: 12 May 2021 (13:59:04 CEST)
When we attempt to define life, we tend to refer to individuals, those that are alive. But these individuals might be cells, organisms, colonies... ecosystems? We can describe living systems at different scales. Which ones might be the best ones to describe different selves? I explore this question using concepts from information theory, ALife, and Buddhist philosophy. After brief introductions, I review the implications of changing the scale of observation, and how this affects our understanding of selves at different structural, temporal, and informational scales. The conclusion is that there is no single ``best'' scale for a self, as this will depend on the scale at which decisions must be made. Different decisions, different scales.
CONCEPT PAPER | doi:10.20944/preprints202104.0743.v1
Subject: Biology, Anatomy & Morphology Keywords: origin of life; virus; evolution; symbiosis; progenotes; fuca;
Online: 28 April 2021 (10:28:30 CEST)
Viruses were classically named after the very same Latin word virus, originally meaning poison or venom. Public understanding of viruses reinforces their “malign” aspects, especially nowadays under the COVID-19 global pandemic. It is our aim here to propose a new way to view viruses and understand their origins and evolution. First, viruses are the most abundant biological systems found on Earth. They can be found almost everywhere and form a subtle biological layer named virosphere. Second, viruses are probably the most important drivers of molecular evolution and they are active agents of ecosystems maintenance and homeostasis, allowing and driving their dynamic modification. A significant number of eukaryotic genomes are composed by genome elements similar to viruses and these endogenous viruses are continuously acting for our equilibrium and fitness. They are responsible for the origin of species-specific orphan genes that allow adaptation through the development of specific traits in separate lineages of eukaryotes. Accumulated evidence indicate that a viral infection was responsible to create the eukaryotic nucleus and, also, it is a syncytium structure caused by viral replication that allows the formation of the placenta. Therefore, viruses were fundamental for the evolutionary fate of eukaryotes and mammals. The presence of virus-specific genes that are absent in cellular organisms indicates that viruses existed before cells. Besides, such as progenotes, viruses are simply ribonucleoproteic entities and their capsids are orders of magnitude simpler than proteolipidic membranes. Here, we (i) propose a complete scenario to describe the major transitions in prebiotic evolution, (ii) present the possibility that viruses emerged before LUCA, and (iii) suggest that viruses originated at the age of progenotes. However, viruses do not form a monophyletic clade. They should be seen as an evolutionary stable strategy recurrently achieved by biological systems to survive. We propose that the word “VIRUS”, known as venom, is historically mistaken and introduce a new interpretation for their name as an acronym for “Very Important Replicator Unit and Symbiont”. But more than being “very important”, viruses are of “Utmost” relevance for the maintenance of life in biosphere, by which reason we suggest referring to them as “UIRUS” to reinforce their incredible role in symbiosis and their beneficial characteristics over the infectious ones.
ARTICLE | doi:10.20944/preprints202103.0312.v1
Subject: Life Sciences, Biochemistry Keywords: Cassava; storage; PPD; starch; shelf-life; postharvest losses.
Online: 11 March 2021 (11:04:22 CET)
Postharvest physiological deterioration (PPD) of fresh cassava roots limits its shelf-life to about 48 hours. There is a demand for simple, cheap, and logistically feasible solutions for extending the shelf life of fresh cassava roots at industrial processes. In this study, three different types of bag materials were tested (woven polypropylene, tarpaulin, and jute as a potential storage solution for cassava roots with different levels of mechanical damages. Microclimate (temperature, humidity, CO2) was monitored to understand the storage conditions for up to 12 days. The results showed that fresh cassava roots could be stored for 8 days, with minimal PPD and starch loss (2.4 %). How-ever, roots with significant mechanical damage (cuts, breakages) had a considerably shorter shelf life in the storage bag, compare to whole roots and roots with retained peduncle (stalk where roots are connected to the main plant). Wetting the roots and type of bag material were not significant factors in determining the shelf life and starch loss. Carbon dioxide concentration in the stores significantly correlated with the starch loss in fresh cassava roots and is proposed as a possible method for continuously and remotely monitoring starch loss in large scale commercial operations and reduce postharvest losses.
ARTICLE | doi:10.20944/preprints202009.0386.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: RTE salads; Microbiological quality; shelf-life; MBS method
Online: 17 September 2020 (08:03:50 CEST)
The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium, and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biological Survey method, in order to propose a simple, affordable and accurate alternative for testing the microbiological quality of products, especially suitable for small and medium enterprises and on-site analyses. The study revealed high, unsatisfactory, total bacterial loads in all analyzed samples at the packaging date and expiring date and a very high prevalence of Salmonella spp. (67%) regardless of the selected varieties and cost-categories; L. monocytogenes was instead not recovered aligning with the results obtained in other studies.
ARTICLE | doi:10.20944/preprints202007.0512.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: RTE salads; Microbiological quality; shelf-life; MBS method
Online: 22 July 2020 (10:09:19 CEST)
The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial success of these products is linked to the growing demand for fresh, healthy and nutritionally valuable products that can be consumed without preparation time and are perceived as safe and very high-quality products. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the MBS method, in order to propose a simple, affordable and accurate alternative for testing the microbiological quality of products, especially suitable for small and medium enterprises and on-site analyses.
HYPOTHESIS | doi:10.20944/preprints202007.0014.v1
Subject: Biology, Other Keywords: life rules; vital determinism; evolution; cooperativity; central dogma
Online: 3 July 2020 (05:46:25 CEST)
We know that living matter must behave in accordance with the universal laws of physics and chemistry. However, these laws are insufficient to explain the specific characteristics of the vital phenomenon and, therefore, we need new principles, intrinsic to biology, which are the basis for developing a theoretical framework for understanding life. Here I propose what I call the seven commandments of life (the Vital Order, the Principle of Inexorability, the Central Dogma, the Tyranny of Time, the Evolutionary Imperative, the Conservative Rule, the Cooperating Thrust) as a set of principles that help us explain the vital phenomenon from an evolutionary perspective. In a metaphorical way, we can consider life like an endless race in which living beings are the runners, who are changing as the race goes on (the evolutionary process), and the commandments the rules.
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Life Cycle Assessment (LCA); Carbon Footprint (CFP); Tourism
Online: 19 February 2020 (10:28:55 CET)
The importance of the contribution from tourism to climate change was pointed out by the International Tourism Organization (UNWTO). By combining process-based Life Cycle Assessment (LCA) and Input-output analysis, several researches have tried to evaluate the impacts of the tourism industry as well as its products and services. Indeed, the tourism sector has a wide range of industries including travel and tour, transportation, accommodation, food and beverage, amusement, souvenirs etc. However, the existing cases did not show a breakdown of the impact on climate change. In this paper, the carbon footprint (CFP) of the Japanese tourism industry was calculated based on tourist consumption, using the Japanese Input-output table and the Japanese tourism industry. It was shown that the total emissions were approximately 136 million t-CO2 per year. The contribution ratio of each stage is as follows: Transport 56.3%, Souvenirs 23.2%, Petrol (direct emissions) 16.9%, Accommodation 9.8%, Food and Beverage 7.5%, Activities 3.0%. Then, in the breakdown, the impact is high in the following order Air transport 24.7%, Petrol (direct emissions) 16.9%,Accommodation 9.8%, Food and Beverage 7.5%, Petrol 6.1%, Textile products 5.3%, Food items 4.9%, Confectionery 4.8%, Rail transport 3.9%, Cosmetics 1.9%, Footwear 1.8%, etc. In addition to transportation, this research also highlighted especially the contribution from souvenirs, accommodation, food and beverages.
ARTICLE | doi:10.20944/preprints201910.0086.v1
Online: 8 October 2019 (10:43:24 CEST)
Phylogenies depict shared evolutionary patterns and structures on a tree topology, enabling the identification of hierarchical and historical relationships. Recent analyses indicate that phylogenetic signals extend beyond the primary structure of protein or DNA, and various aspects of codon usage biases are phylogenetically conserved. Several functional biases exist within genes, including the number of codons that are used, the position of the codons, and the overall nucleotide composition of the genome. Codon usage biases can significantly affect transcription and translational efficiencies, leading to differential gene expression. Although systematic codon usage biases originate from the overall GC content of a species, ramp sequences, codon aversion, codon pairing, and tRNA competition also significantly affect gene expression and are phylogenetically conserved. We review recent advances in analyzing codon usage biases and their implications in phylogenomics. We first outline common phylogenomic techniques. Next, we identify several codon usage biases and their effects on secondary structure, gene expression, and implications in phylogenetics. Finally, we suggest how codon usage biases can be included in phylogenomics. By incorporating various codon usage biases in common phylogenomic algorithms, we propose that we can significantly improve tree inference. Since codon usage biases have significant biological implications, they should be considered in conjunction with other phylogenetic algorithms.
Subject: Social Sciences, Education Studies Keywords: Teacher Competence; Classroom Satisfaction; Life Satisfaction; PE Students
Online: 28 March 2019 (11:27:41 CET)
The aim of this article was to assess how the professional competence of PETs (Physical Education Teachers) can predict student satisfaction in high school and student satisfaction with life itself. In line with these aims, this study was completed as a cross-sectional study, which was carried out in a total 890 Physical Education (PE) students. Of the research group, 50.3% were female and 49.7% were male. Age average was 15.49 years old for females (SD 1.79) and 15.00 years old for males (SD 2.00). The data collection instrument was the Intrinsic Satisfaction Classroom Scale and Satisfaction with Life Scale. The results are presented as descriptive statistics, correlations and structural equation modelling analysis, and they show that the competences of the PE teacher determine in great measure student’s satisfaction with school and with their own personal lives.
ARTICLE | doi:10.20944/preprints201810.0623.v1
Subject: Social Sciences, Sociology Keywords: precarity; decent works; life satisfaction; SMEs; PLS-SEM
Online: 26 October 2018 (09:36:59 CEST)
This study measures key indicators of perceived precarity and decent working conditions and their relative effects on life satisfaction of workers in small and medium-sized enterprises. Using a random sample survey, we interviewed 103 workers in four districts of Sylhet division in Bangladesh. Utilizing Smart PLS application for structural equation modeling, we iterated the samples 1000 times which resulted in a new sample size standing at 499. We used a Likert-type five-point scaling technique, with appropriate items related to the latent constructs of the model, for path analysis. We found perceived precariousness has the highest causal relations with a path coefficient of 0.706 with social dialogue (an indicator of decent working conditions) followed by 0.539 with working hour issue, 0.345 with life satisfaction and 0.301 with the unacceptable work issue. The importance-performance map analysis confirms that perceived precarity is the most critical construct for worker’s life satisfaction. Thus, in a ceteris paribus situation, an increase of one point in the performance on the perceived precarity is expected to increase in the performance on the life satisfaction by a total effect level of 0.428. Therefore, we recommend further attention should be paid by the policymakers to the issue of consciousness of the precarity at the workplace for a better life satisfaction of workers.
ARTICLE | doi:10.20944/preprints201705.0107.v1
Subject: Engineering, Civil Engineering Keywords: Cement; Multicriteria analysis; Life Cycle Analysis; Construction industry
Online: 12 May 2017 (17:45:58 CEST)
The attention to sustainable-related issues has grown fast in recent decades. The experience gained with these themes reveals the importance of considering this topic in the construction industry, which represents an important sector in the world. This work consists on conducting a multicriteria analysis of four cement powders, with the objective of calculating and analysing the environmental, human health and socio-economic effects of their production processes. The economic, technical, environmental and safety performances of the examined powders result from official, both internal and public, documents prepared by the producers. The Analytic Hierarchy Process permitted to consider several indicators (i.e. environmental, human health related and socio-economic parameters) and to conduct comprehensive and unbiased analyses which gave the best, most sustainable cement powder. As assumed in this study, the contribution of each considered parameter to the overall sustainability has a different incidence, therefore the procedure could be used to support on-going sustainability efforts under different conditions. The results also prove that it is incorrect to consider only one parameter to select the ‘best’ cement powder, but several impact categories should be considered and analysed if there is an interest for pursuing different, often conflicting interests.
ARTICLE | doi:10.20944/preprints201703.0187.v1
Subject: Materials Science, Metallurgy Keywords: medium-carbon steel; fatigue life estimation; surface roughness
Online: 24 March 2017 (10:50:11 CET)
Medium-carbon steel is commonly used for the rail, wire ropes, tire cord, cold heading, forging steels, cold finished steel bars, machinable steel and so on. Its fatigue behavior analysis and fatigue life estimation play an important role in the machinery industry. In this paper, the estimation of fatigue life of medium-carbon steel with different surface roughness using established S-N and P-S-N curves is presented. To estimate the fatigue life, the effect of the average surface roughness on the fatigue life of medium-carbon steel has been investigated using 75 fatigue tests in three groups with average surface roughness (Ra): 0.4μm, 0.8μm, and 1.6μm respectively. S-N curves and P-S-N curves have been established based on the fatigue tests. The fatigue life of medium-carbon steel is then estimated based on Tanaka-Mura crack initiation life model, the crack propagation life model using Paris law, and material constants of the S-N curves. 6 more fatigue tests have been conducted to validate the presented fatigue life estimation formulation. The experimental results have shown that the presented model could estimate well the mean fatigue life of medium-carbon steel with different surface roughness
ARTICLE | doi:10.20944/preprints202211.0322.v1
Subject: Life Sciences, Genetics Keywords: life; paralife; utility-products; UP-paralife; utility-selection; UP-evolvability; coevolution; intelligence; stone tools; language-catalysis; creativity; exoplanet; intelligent life
Online: 17 November 2022 (03:06:22 CET)
When animals evolve sufficient intelligence and dexterity to be able to learn to fabricate utility products (UPs) like tools, the UP's they produce become part of an induced-reproduction system that intrinsically shares many life-like traits with biological organisms, including genome-like fabrication and operation information that is physically-encoded in the animal fabricator’s neural networks. When this set of life- like traits includes a sufficient capacity for system-improving cultural evolution (UP-evolvability), the UPs become ‘para-alive’, i.e., nearly alive, or a form of non-biological UP-paralife that is equivalent to the life- status of biological viruses, plasmids, and transposons. In the companion paper I focus on the evolution of UP-paralife in the context of modern, language-capable humans and its predicted evolution going forward in time (Rice 2022). Here I look backward in time and focus on the origin of UP-paralife and its subsequent coevolution with human intelligence. I begin by determining the pathways leading to the evolution of large brains in the rare lineages of biological life that have sufficient intelligence to learn to fabricate tools –a critical first step in the evolution of UP-paralife. The simplest forms of these learning- based UPs, made by species like chimpanzees and New Caledonian crows, represent only proto-UP- paralife because they lack sufficient UP-evolvability. Expanded UP-evolvability required a combination of three attributes that enabled continuous niche-expansion of the animal fabricator via a new and advanced form of UP-mediated teamwork (TW): i) self-domestication that facilitated TW among low-related individuals, ii) learned volitional words (protolanguage) that represent ephemeral UPs that coordinate TW, and iii) learned fabrication of simple flaked-stone tools with cutting and chopping capabilities (a UP to make other structural UPs) that expanded teammate phenotypes and TW capabilities. This specific triad of attributes is synergistic because each one acts as a TW-enhancer that can gradually erode different components of the three major constraints on TW operation and expansion: too much selfishness, insufficient coordination signals, and insufficient physical traits of teammates. The increase in UP- evolvability was transformative and marked the origin of UP-paralife and the initiation of coevolution between UP-paralife (cultural evolution) and the intelligence of its hominin/human symbiont (genetic evolution) that fostered 2.5 million years of: i) continuous brain size increase and niche-expansion within the genus Homo, and ii) parallel advances in the diversity, complexity and uses of UP-paralife. This coevolution also fostered evolutionary expansion of word-based communication, and eventually language, that acted in a catalyst-like manner to facilitate the evolution of increasingly complex forms of imagination, reasoning, mentalizing, and UP-generating technology. I next focus on the evolution of creativity in the human lineage –in the form of divergent thinking and creative imagination. I conclude that the evolution of this advanced cognitive feature required a preadaptation of sufficient intelligence and is the component of human cognition that was the major causal factor generating the greatly expanded diversity and complexity of UP-paralife currently associated with modern humans. Lastly, I apply my findings to the issue of the prevalence of extraterrestrial intelligent life. I conclude that any exoplanets with detected chemical life will very rarely (e.g., probability ~10-5 for a planet closely matching Earth’s characteristics) have evolved intelligence equalling or exceeding that of humans.
ARTICLE | doi:10.20944/preprints202207.0463.v1
Subject: Life Sciences, Other Keywords: Nocturia; aging male symptoms; Quality of life; Health-related Quality of life; Male adults; NQoL; Urinary frequency; Bedtime urination; sleep
Online: 29 July 2022 (13:13:15 CEST)
Background: The link between nocturia and aging male symptoms (AMS) has not been scientifically established. This study aimed to measure the degree of severity of AMS that impact on the health-related quality-of-life (HRQoL) in adult males living with nocturia, and to determine the predictive values of nocturnal factors on AMS. Methods: It is an extended analysis of new data collected by using the Hong Kong Traditional AMS (HK-AMS) scale and Cantonese version of the Pittsburgh Sleep Quality Index (PSQI) in a recently published cross-sectional population-based survey. Results: Of the 781 respondents that have completed the set of questionnaires, 68% and 61% of men living with nocturia reported clinically significant (at moderate-to-severe levels) somato-vegetative and sexual AMS, whereas the prevalence and severity were increased with advancing nighttime voiding frequency. The nocturia-specific QoL (NQoL) score and nocturnal frequency were found to be significant predictive factors for composite, somato-vegetative and sexual AMS, in addition to age, global OSQI score, and certain metabolic diseases. Conclusions: Current findings suggested the inclusion of nocturia when measuring the male-specific HRQoL related to aging.
REVIEW | doi:10.20944/preprints201712.0172.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: palliative care team; seriously ill patients; end-of-life; quality of life; symptom relief; acute palliative care unit; cost savings
Online: 25 December 2017 (08:50:18 CET)
Traditionally, palliative care (PC) systems focused on the needs of advanced cancer patients. But, most patients needing PC have end-stage organ diseases. Similarly, PC models focused on the needs of patients in hospice or at home; however, in most cases PC is provided in acute hospitals. Indeed, the symptom burden that these patients experience in the last year of life frequently forces them to seek care in Emergency Department. The majority of them are admitted to the hospital and many die. This issue poses important concerns. Despite the efforts of attending healthcare professionals, inhospital patients do not receive optimal care near the end-of-life. Also, evidence is emerging that delay in identifying patients needing PC have a detrimental impact on their quality of life (QoL). Therefore, there is an urgent need to early and properly identify these patients among those hospitalized. Several trials reported the efficacy of PC in improving the QoL in these patients. Each hospital should ensure that a multidisciplinary PC team is available to support attending physicians to achieve the best QoL for both PC patients and their families. This review discusses the role and the impact of inhospital PC in patients with end-stage disease or advanced cancer.
REVIEW | doi:10.20944/preprints202206.0370.v1
Subject: Life Sciences, Other Keywords: GADV hypothesis; origin of life; protein 0th-order structure; origin of protein; [GADV]-microsphere; origin of gene: the core life system
Online: 28 June 2022 (03:41:15 CEST)
One of the problems, which make it difficult to solve the mystery of the origin of life, would be how life emerged in chemically complex messy environments on the primitive Earth. It is considered that three main points contributed to open the way to the emergence of life. (1) A characteristic inherent in [GADV]-amino acids, which are easily produced with prebiotic means. (2) Protein 0th-order structure or [GADV]-amino acid composition generating water-soluble globular protein with some flexibility, which can be produced even by random joining of [GADV]-amino acids. (3) Formation of versatile [GADV]-microspheres, which can grow, divide, proliferate even without genetic system, was the emergence of proto-life. (4) [GADV]-microspheres with a higher proliferation ability than others could be selected. The proto-Dawin evolution made it possible to proceed forward to creation of the core life system composed of (GNC)n gene, anticodon stem-loop tRNA or AntiC-SL tRNA (GNC genetic code) and [GADV]-protein. (5) Eventually, the first genuine life with the core life system emerged. Thus, the formation processes of [GADV]-protein and (GNC)n gene in chemically complex messy environments were the steps to the emergence of genuine life.