REVIEW | doi:10.20944/preprints202204.0232.v1
Subject: Physical Sciences, Other Keywords: Air Quality; Urban air quality; air quality measurement systems
Online: 26 April 2022 (09:57:05 CEST)
Urban air quality is increasingly becoming a cause for concern for the health of the human population. The poor air quality is already wreaking havoc in major cities of the world, where serious health issues and reduction of average human life by a factor of years are reported. The air quality in developing countries can become worse as they undergo development. The urban air quality varies non-linearly depending upon the various factors such as land use, industrialization, waste disposal, traffic volume, etc. To address this problem, it is necessary to look at the plethora of available literature from multiple perspectives such as types and sources of pollutants, meteorology, urban mobility, urban planning and development, health care, economics, etc. In this paper, we provide a comprehensive survey of the state-of-the-art in urban air quality. We first review the fundamental background on air quality and present the emerging landscape of urban air quality. We then explore the available literature from multiple urban air quality measurement projects and provides the insights uncovered in them. We then take a look at the sources that are significantly contributing to polluting the air quality. Finally, we highlight open issues and research challenges in dealing with urban air pollution.
ARTICLE | doi:10.20944/preprints202009.0685.v1
Subject: Earth Sciences, Environmental Sciences Keywords: fusion; pansharpening; image quality; Worldview-3; quality index
Online: 28 September 2020 (11:05:51 CEST)
Image fusion is a useful tool for producing a high-resolution multispectral image to be used for land use and land cover mapping. In this study, we use nine pansharpening algorithms namely Color Normalized (CN), Gram-Schmidt (GS), Hyperspherical Color Space (HCS), High Pass Filter (HPF), Nearest-Neighbor Diffusion (NND), Principal Component Analysis (PCA), Resolution Merge (RM), Stationary Wavelet Transform (SWT), and Wavelet Resolution Merge (WRM) to fusion Worldview-3 multispectral Bands and panchromatic band. In spectral and spatial fidelity, several image quality metrics are used to evaluate the performance of pansharpening algorithms. The SWT and PCA algorithms showed better results compared to other pansharpening algorithms while GS and CN algorithms showed the worst results for the original image fusion. The effect of fusion on each band was separately investigated and according to the calculations, we found that the CoastalBlue band and the Blue band showed the best result and the NIR-1 band and NIR-2 band show the worst result for the original image fusion. In the end, we conclude that the choice of fusion method depends on the requirement of remote sensing application.
ARTICLE | doi:10.20944/preprints201907.0339.v2
Subject: Engineering, Civil Engineering Keywords: Water Quality Index; irrigation water quality; Tabriz Aquifer
Online: 9 September 2019 (08:42:20 CEST)
The key goal of the current study was to determine suitable areas of water pumping for drinking and agricultural harvest in Tabriz aquifer, located in East Azerbaijan province, northwest Iran. In the study area, groundwater is the key foundation of water for drinking and farming requirements. Groundwater compatibility study was conducted by analyzing Electrical conductivity (EC), Total dissolved solids (TDS), Chloride (Cl), Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K), Sulfate (SO4), Total hardness (TH), Bicarbonate (HCO3), pH, carbonate (CO3) and Sodium Adsorption Ratio (SAR) obtained from 39 wells in the period of 2003 to 2014. For this purpose, the Water Quality Index (WQI) and irrigation water quality (IWQ) index were utilized. The WQI index zoning exposed that the groundwater of the study area for drinking purposes is categorized as excellent, good and poor water. Most drinking water harvested for urban and rural areas are in the class of 'excellent water'. The results revealed that about 37 percent (296 km2) of groundwater has high compatibility, and 63 percent of the study area (495 km2) has average compatibility for agricultural purposes. The trend of IWQ and WQI indexes demonstrates that the groundwater is getting worse over the time.
ARTICLE | doi:10.20944/preprints201805.0240.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: background reconstruction; image quality assessment; image dataset; subjective evaluation; perceptual quality; objective quality metric
Online: 17 May 2018 (09:36:33 CEST)
With an increased interest in applications that require a clean background image, such as video surveillance, object tracking, street view imaging and location-based services on web-based maps, multiple algorithms have been developed to reconstruct a background image from cluttered scenes. Traditionally, statistical measures and existing image quality techniques have been applied for evaluating the quality of the reconstructed background images. Though these quality assessment methods have been widely used in the past, their performance in evaluating the perceived quality of the reconstructed background image has not been verified. In this work, we discuss the shortcomings in existing metrics and propose a full reference Reconstructed Background image Quality Index (RBQI) that combines color and structural information at multiple scales using a probability summation model to predict the perceived quality in the reconstructed background image given a reference image. To compare the performance of the proposed quality index with existing image quality assessment measures, we construct two different datasets consisting of reconstructed background images and corresponding subjective scores. The quality assessment measures are evaluated by correlating their objective scores with human subjective ratings. The correlation results show that the proposed RBQI outperforms all the existing approaches. Additionally, the constructed datasets and the corresponding subjective scores provide a benchmark to evaluate the performance of future metrics that are developed to evaluate the perceived quality of reconstructed background images.
ARTICLE | doi:10.20944/preprints202204.0164.v1
Subject: Social Sciences, Finance Keywords: Environmental quality; institutional quality; ethnic conflicts; socio-economic factors
Online: 18 April 2022 (10:38:40 CEST)
Nowadays, determining the socioeconomic factors' influence on environmental quality is a crucial issue for policymakers. We aim to explore the impact of socioeconomic factors i.e., ethnic conflicts inform ethnic fragmentation, institutions quality effectiveness, and energy consumption on environmental quality by testing the various hypotheses (Pollution Halo Hypothesis, IPAT, and EKC) in 40 selected Asian countries throughout 1993-2019. We also use a set of control variables which are gross domestic product per capita, foreign direct investment inflows, and population growth to determine their impact on environmental quality. We use the Panel Quintile Regression Method of 0.25, 0.5, and 0.75 to analyze the results. We find ethnic conflict negatively affects the environmental quality at all quantiles. The institution's variables regulatory quality and rule of law negatively influence the environmental quality. Our result supports Porter's hypothesis because the effect of direct foreign investment on the amount of CO2 emissions is negative and significant at 0.25, 0.5, and 0.75 quantiles which states that foreign direct investment in the host country supports environmental quality. Furthermore, our results support the IPAT hypothesis in selected Asian countries.
ARTICLE | doi:10.20944/preprints202104.0721.v1
Online: 27 April 2021 (12:52:15 CEST)
The success of a software product depends on several factors. Given that different organizations and institutions use software products, the need to have a quality and desirable software according to the goals and needs of the organization makes measuring the quality of software products an important issue for most organizations and institutions. To be sure of having the right software. It is necessary to use a standard quality model to examine the features and sub-features for a detailed and principled study in the quality discussion. In this study, the quality of Word software was measured. Considering the importance of software quality and to have a good and usable software in terms of quality and measuring the quality of software during the study, experts and skilled in this field were used and the impact of each factor and quality characteristics. It was applied at different levels according to their opinion to make the result of measuring the quality of Word software more accurate and closer to reality. In this research, the quality of the software product is measured based on the fuzzy inference system in ISO standard. According to the results obtained in this study, it is understood that quality is a continuous and hierarchical concept and the quality of each part of the software at any stage of production can lead to high quality products.
ARTICLE | doi:10.20944/preprints202008.0589.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: globalization; systems thinking; global quality management; global quality system
Online: 27 August 2020 (03:28:46 CEST)
A global approach towards quality management highlights the need for constructing a new body of knowledge that views the field of global quality from a systems perspective. Based on the results of field experiments, and in light of the need to develop new global quality management terminology, the current article presents several key concepts in this field, with emphasis on a systems-oriented rationale and perspective. As such, the article is an important stage in building this body of knowledge, and towards the conceptualization of key variables used in global quality management, from a systems approach that interacts with the fields of international management and strategic management.
ARTICLE | doi:10.20944/preprints202110.0411.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Automotive; Resistance Spot Welding; Quality Assurance; Quality Monitoring; Artificial Intelligence
Online: 27 October 2021 (13:27:03 CEST)
Resistance spot welding is an established joining process in the production of safety-relevant components in the automotive industry. Therefore, a consecutive process monitoring is essential to meet the high-quality requirements. Artificial neural networks can be used to evaluate the process parameters and signals to ensure the individual spot weld quality. The predictive accuracy of such algorithms depends on the provided training data set and the prediction of untrained data is challenging. The aim of this paper is to investigate the extrapolation capability of the multi-layer perceptron model. That means, that the predictive performance of the model will be tested with data that clearly differs from the training data in terms of material and coating composition. Therefore, three multi-layer perceptron regression models were implemented to predict the nugget diameter from process data. The three models were able to predict the trained datasets very well. The models, which were provided with features from the dynamic resistance curve predicted the new dataset better than the model with only process parameters. This study shows the beneficial influence of the process signals on the predictive accuracy and robustness of artificial neural network algorithms. Especially, when predicting a data set from outside of the training space.
ARTICLE | doi:10.20944/preprints202010.0092.v1
Subject: Engineering, Automotive Engineering Keywords: ANOVA; Asphalt Binder Extraction; Quality Assurance; Quality Control; RAP; RAS
Online: 5 October 2020 (14:06:31 CEST)
Asphalt binder requires more investigation to be accurately and precisely extracted since it is a significant procedure for quality control quality assurance (QC/QA) and subsequent binder characterization. In this research, the authors provided a hands-on experience with binder extraction to deliver recommendations concerning the sensitive steps that may affect the outcomes (extracted binder content, Pbe%). Based on the extraction by the centrifuge method, two mineral matter determination methods (ashing and centrifuge) were addressed. Field cores were investigated with comparing the Pbe% to the actual binder content, Pba%. Analysis of variance (ANOVA) and Tukey Post-Hoc statistical analyses, in addition to linear least square regression analysis, were used to show the significance of difference according to 38 variant cores randomly obtained from the field segments (in-service roads) via the first two weeks from the construction date. Such cores involved reclaimed asphalt pavement (RAP), reclaimed asphalt shingles (RAS), and a wide range of additives. The two extraction methods were compared with concluding that the centrifuge method was highly recommended based on a quantitative evaluation, which delivered the same average Pba% based on the 38 cores. Furthermore, the centrifuge method provided much saving in the experimental time (almost half the time required for the ashing method). It was found that the ashing outcomes were equal to the centrifuge outcomes with disregarding the ammonium carbonate addition. Thus, it could be recommended to reassess the ammonium carbonate addition as it might excessively compensate for fake minerals that have not been lost by the ignition oven.
ARTICLE | doi:10.20944/preprints201810.0537.v1
Subject: Social Sciences, Marketing Keywords: emotion; commitment; brand loyalty; willingness to pay more; coffee quality; service quality; physical environment quality; price fairness
Online: 23 October 2018 (11:58:03 CEST)
: Following the phenomenal growth of and competition among coffee chain retailers, the coffee chain market has expanded substantially thanks to rising income levels, the increasing young population, and rapidly changing lifestyles. Attracting consumers’ attention and enhancing their loyalty behaviors have become very difficult for coffee chain retailers. This study seeks to understand the mechanisms through which emotions and the dedication-constraint model lead to brand loyalty and willingness to pay more to certain coffee chain retailers. Emotions and the dedication-constraint model are major factors in the research, but few studies have combined them to examine the formation of loyalty behaviors. This study synthesizes emotional responses and the dedication-constraint model to develop a theoretical model. Based on the ambivalent view of emotions, it also examines how positive and negative emotions affect the combination of brand loyalty and willingness to pay more to certain coffee chain retailers. Moreover, it identifies the antecedents of affective and calculative commitments in the context of coffee chain retailers. Our findings indicate that loyalty behaviors (dedication- and constraint-based mechanisms from brand loyalty and willingness to pay more to certain coffee chain retailers), emotional responses, and affective and calculative commitments significantly affect brand loyalty directly and indirectly through both positive and negative emotions. Furthermore, service quality, physical environment quality, and price fairness significantly affect affective commitments, while price fairness significantly affects both affective and calculative commitments. Finally, affective and calculative commitments significantly affect willingness to pay more, both directly and indirectly, through positive emotions and affect it directly through negative emotions. The results’ theoretical and managerial implications and possible future research directions are discussed.
ARTICLE | doi:10.20944/preprints202012.0424.v1
Subject: Medicine & Pharmacology, Allergology Keywords: nursing homes; quality indicators; quality measurement; palliative care; quality of care; end of life care; advance care planning
Online: 17 December 2020 (11:07:43 CET)
An increasingly frail population in nursing homes accentuates the need for high quality care at the end of life and better access to palliative care in this context. Implementation of palliative care and its outcomes can be monitored by using quality indicators. Therefore, we developed a quality indicator set for palliative care in nursing homes and a tailored measurement procedure using a mixed-methods design. We developed the instrument in three phases: 1) literature search, 2) interviews with experts and 3) indicator and measurement selection by expert consensus (RAND/UCLA). Second, we pilot tested and evaluated the instrument in nine nursing homes in Flanders, Belgium. After identifying 26 indicators in the literature and expert interviews, 19 of them were selected through expert consensus. Setting-specific themes were advance care planning, autonomy and communication with family. The quantitative and qualitative analyses showed the indicators were measurable, had good preliminary face validity and discriminative power and were considered useful in terms of quality monitoring according to the caregivers. The quality indicators can be used in a large implementation study and process evaluation in order to achieve continuous monitoring of the access to palliative care for all residents in nursing homes.
ARTICLE | doi:10.20944/preprints201912.0148.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: Quality of Experience; Quality of Service; QoE evaluation video on demand; Quality of Service; QoS correlation; subjective testing
Online: 11 December 2019 (04:46:57 CET)
In addition to the traditional QoS metrics of delay, delay jitter, and packet loss probability (PLP), Quality of Experience (QoE) is now widely accepted as a numerical proxy for actual user experience. The literature has reported many mathematical mappings between QoE and QoS. These QoS parameters are measured by the network providers using sampling. There are some papers studying sampling errors in QoS measurements; however there is no account of propagation of these sampling errors to QoE evaluation. In this paper, we used industrially acquired measurements of PLP and jitter to evaluate the sampling errors and correlation in measurements. Focussing on Video-on-demand (VoD) applications, we use subjective testing and regression to map QoE metrics onto PLP and jitter. The resulting mathematical functions of QoE and theory of error propagation was used to evaluate the propagated error in QoE, and this error was represented as confidence interval. Using the guidelines of UK government for sampling, our results indicate that confidence intervals around estimated QoE in a busy hour can be between MOS=1 to MOS=5 at targeted operating point of QoS parameters. These results are a new perspective on QoE evaluation, and are of great significance to all organisations that need to estimate the QoE VoD applications precisely.
ARTICLE | doi:10.20944/preprints202105.0479.v1
Subject: Engineering, Automotive Engineering Keywords: software quality, Adaptive Neural Fuzzy, ISO standard, quality model, Inference system
Online: 20 May 2021 (10:31:56 CEST)
Computer systems are involved in many critical human applications today, so that a small error can lead to serious and dangerous problems. These errors can be from an error in the incorrect design of the user interface to an error in the program code. The success of a software product depends on several factors. Given that different organizations and institutions use software products, the need to have a quality and desirable Software according to the goals and needs of the organization makes measuring the quality of software products. an important issue for most organizations and institutions, To be sure of having the right software. It is necessary to use a standard quality model to examine the features and sub-features for a detailed and principled study in the quality discussion. In this study, the quality of Word software was measured by Adaptive Neural Fuzzy Inference System. In recent years, powerful systems called fuzzy inference systems on The basis of adaptive neural network (ANFIS) has been used in various sciences. Using the power of neural network training and the linguistic advantage of fuzzy systems, these types of systems have been able to realize the advantages of the two in terms of analyzing very powerful complex processes. Considering the importance of software quality and to have a good and usable software in terms of quality and measuring the quality of software during the study. It was applied at different levels to make the result of measuring the quality of Word software more accurate and closer to reality. In this research, the quality of the software product is measured based on the adaptive neural-fuzzy inference system in ISO standard. According to the results obtained in this study, it is understood that quality is a continuous and hierarchical concept and the quality of each part of the software at any stage of production can lead to high quality products.
Subject: Life Sciences, Biochemistry Keywords: HIV viral load; external quality assessment; verification; quality; thermostable; PrimeStore MTM
Online: 18 January 2021 (12:24:31 CET)
The tiered laboratory framework for HIV viral load monitoring accommodates a range of HIV viral load testing platforms, with quality assessment critical to ensure quality patient testing. HIV plasma viral load testing is challenged by the instability of viral RNA. An approach using an RNA stabilizing buffer is described for the Xpert® HIV-1 Viral Load (Cepheid) assay and was tested in remote laboratories in South Africa. EDTA-plasma panels with known HIV viral titres were prepared in PrimeStore molecular transport medium for per-module verification and per-instrument external quality assessment. The panels were transported at ambient temperatures to 13 testing laboratories during 2017 and 2018, tested according to standard procedures and uploaded to a web portal for analysis. A total of 275 quality assessment specimens (57 verification panels and two EQA cycles) were tested. All participating laboratories met study verification criteria (n=171 specimens) with an overall concordance correlation coefficient (ρc) of 0.997 (95% confidence interval [CI]: 0.996 to 0.998) and a mean bias of -0.019 log cp/mL (95% CI: -0.044 to 0.063). The overall EQA ρc (n=104 specimens) was 0.999 (95% CI: 0.998 to 0.999), with a mean bias of 0.03 log cp/mL (95% CI: 0.02 to 0.05). These panels are suitable for use in quality monitoring of Xpert® HIV-1 VL and are applicable to laboratories in remote settings.
ARTICLE | doi:10.20944/preprints202011.0299.v1
Subject: Earth Sciences, Atmospheric Science Keywords: groundwater quality; extended SWAT model; water quality parameters; Athabasca River Basin
Online: 10 November 2020 (10:32:09 CET)
Groundwater is a vital resource for human welfare. However, due to various factors, groundwater pollution is one of the main environmental concerns facing. Yet, it is challenging to simulate groundwater quality dynamics due to the insufficient representation of nutrient percolation processes in the soil and Water Assessment Tool model. The objectives of this study were extending the SWAT module to predict groundwater quality. The results proved a linear relationship between observed and calculated groundwater quality considering No3 and TDS with R2, NSE and PBIAS values in the satisfied ranges, albeit underestimation and overestimation were observed due to limited data availability. These results highlight that nitrate and TDS concentrations and variability in groundwater may used as a tool in surface water quality that have to be assumed for designing adaptive management scenarios. Hence, extended SWAT model could be a powerful tool for future regional to global scale modelling of nutrient loads supporting effective surface and groundwater management.
ARTICLE | doi:10.20944/preprints201901.0260.v1
Subject: Earth Sciences, Environmental Sciences Keywords: reservoir; water quality indexes; GEVORG index; Armenian Water Quality Index; Armenia
Online: 25 January 2019 (15:03:46 CET)
In this article, the quality of water in the reservoirs of Lake Arpi, Lake Yerevan, Akhuryan, Azat, Aparan and Kechut was estimated with usage of the Armenian Water Quality Index. It was established that in the waters of reservoirs the the maximum permissible concentration of copper, vanadium, aluminum, chromium, manganese, iron, NH4+ and NO2- regularly increases. The following computational algorithm was used for determination of the Armenian Water Quality Index values: to determine the number of cases of MPC excess of i-substance or indicator of water –n; to estimate the total amount of cases of the maximum permissible concentration (N) – N = ∑n; to computes log2N, nlog2n and ∑nlog2n; to determine geoecological syntropy (I) and entropy (H): I = ∑ nlog2n/N and H = log2N – I. Then, Geo-Ecological Evolving Organized index index was determined: G = H/I. Further, the total amount multiplicity of MAC exceedances was estimated: (M) - M=∑m and log2M was computed. Finally, Armenian Water Quality Index was obtained: AWQI = G + 0.1log2M. It was established that the Armenian Water Qquality Index showed a linear dependence on the Water Contamination Index, the Specific Combinatory Water Quality Index, the Geo-Ecological Evolving Organized index and an inverse dependence on the Canadian Water Quality Index.
ARTICLE | doi:10.20944/preprints202112.0126.v1
Online: 8 December 2021 (14:10:05 CET)
The purpose of this research is to determine if the tradeoffs that Kissick proposed among cost containment, quality, and access remain as rigidly interconnected as originally conceived in the contemporary health care context. Although many have relied on the Kissick model to advocate for health policy decisions, to our knowledge, the model has never been empirically tested. Some have called for policy makers to come to terms with the premise of the Kissick model tradeoffs, others have questioned the model given the proliferation of quality enhancing initiatives, automation, and information technology in the health care industry. One wonders whether these evolutionary changes alter or disrupt the originality of the Kissick paradigms themselves. Methods: Structural Equation Modeling (SEM) was used to evaluate the Kissick hypothetical relationships among the unobserved constructs of cost, quality, and access in hospitals for the year 2018. Hospital data were obtained from Definitive Healthcare a subscription site which contains Medicare data as well as non-Medicare data for networks, hospitals, and clinics (final n= 2,766). Results: Reporting significant net effects as defined by our chosen study variables, we find that as quality increases costs increase, as access increases quality increases, and as access increases, costs increase. Policy and Practice Implications: Our findings lend continued relevance to a balanced approach to health care policy reform efforts. Simultaneously bending the health care cost curve, increasing access to care, and advancing quality of care is as challenging now as it was when the Kissick model was originally conceived.
ARTICLE | doi:10.20944/preprints201709.0113.v1
Online: 23 September 2017 (11:05:13 CEST)
The Delaware River has made a marked recovery in the half-century since the adoption of the Delaware River Basin Commission (DRBC) Compact in 1961 and passage of the Federal Clean Water Act amendments during the 1970s. During the 1960s, the DRBC set a 3.5 mg/l dissolved oxygen criteria for the river based on an economic analysis that concluded a waste load abatement program designed to meet fishable water quality goals would generate significant recreation and environmental benefits. Scientists with the Delaware Estuary Program have recently called for raising the 1960s DO criteria along the Delaware River from 3.5 mg/l to 5.0 mg/l to protect anadromous American shad and Atlantic sturgeon and address the prospect of rising temperatures, sea levels, and salinity in the estuary. This research concludes through a marginal abatement cost (MAC) analysis that it would be cost effective to raise DO levels to meet a more stringent standard by prioritizing agricultural conservation and wastewater treatment investments in the Delaware River watershed to reduce 90% of the pollutant load 13.6 million kg/year of nitrogen (30 million lb/year) for $160 million at 35% of the $449 million annual cost. The annual least cost to reduce nitrogen loads and raise dissolved oxygen levels to meet more stringent water quality standards in the Delaware River totals $45 million for atmospheric NOX reduction, $130 million for wastewater treatment, $132 million for agriculture conservation, and $141 million for urban stormwater retrofitting. This 21st century least cost analysis estimates that $50 million/year is needed to reduce pollutant loads in the Delaware River to raise dissolved oxygen levels to 4.0 mg/l, $150 million/year is needed to reach 4.5 mg/l, and $449 million/year is needed to reach 5.0 mg/l.
REVIEW | doi:10.20944/preprints202106.0320.v1
Subject: Keywords: RT-qPCR; assay validity; standard curve; quality assurance; quality control; wastewater surveillance
Online: 11 June 2021 (14:10:51 CEST)
The coronavirus disease 2019 (COVID-19) pandemic has led to wastewater surveillance becoming an important tool for monitoring the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within communities. As a result, molecular methods, in particular reverse transcription-quantitative PCR (RT-qPCR), have been employed to generate large data sets aimed at the detection and quantification of SARS-CoV-2 in wastewater. Although RT-qPCR is rapid and sensitive, there is no standard method that fits all use cases, there are no certified quantification standards and experiments are carried out using numerous different assays, reagents, instruments, and data analysis protocols. These variations can lead to the reporting of erroneous quantitative data resulting in potentially misleading interpretations and conclusions. We have reviewed the SARS-CoV-2 wastewater surveillance literature focusing on the variability of RT-qPCR data as revealed by inconsistent standard curves and associated parameters. We find that variation in these parameters and deviations from best practices as described in The Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines suggest a lack of reproducibility and reliability in quantitative measurements of SARS-CoV-2 RNA in wastewater.
ARTICLE | doi:10.20944/preprints201807.0517.v3
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Robust Design, Taguchi Method, Product Design, Manufacturing Systems, Quality Engineering, Quality Loss Function.
Online: 25 August 2022 (08:36:39 CEST)
One of the main technological and economic challenges for an engineer is designing high-quality products in manufacturing processes. Most of these processes involve a large number of variables included the setting of controllable (design) and uncontrollable (noise) variables. Robust Design (RD) method uses a collection of mathematical and statistical tools to study a large number of variables in the process with a minimum value of computational cost. Robust design method tries to make high-quality products according to customers’ viewpoints with an acceptable profit margin. This paper aims to provide a brief up-to-date review of the latest development of RD method particularly applied in manufacturing systems. The basic concepts of the quality loss function, orthogonal array, and crossed array design are explained. According to robust design approach, two classifications are presented, first for different types of factors, and second for different types of data. This classification plays an important role in determining the number of necessity replications for experiments and choose the best method for analyzing data. In addition, the combination of RD method with some other optimization methods applied in designing and optimizing of processes are discussed.
ARTICLE | doi:10.20944/preprints202106.0440.v1
Subject: Earth Sciences, Atmospheric Science Keywords: air quality; thermal comfort; air quality index; heat index; wind chill; Bulgaria; Europe
Online: 16 June 2021 (11:18:02 CEST)
Air pollution is responsible for any adverse effects on human beings. Thermal discomfort, on the other hand, is able to overload the human body and eventually provoke health implications due to the heat imbalance. Methods: The aim of the present work is to study the behavior of two bio-climatic indexes and statistical characteristics of the air quality index for Sofia city - the capital of Bulgaria for the period 2008 - 2014. The study is based on WRF-CMAQ model system simula-tions with a spatial resolution of 1 kilometer. The air quality is estimated by the air quality index, taking into account the influence of different pollutants and the thermal conditions by two indi-ces, respectively, for hot and cold weather. Results: It was found that half of the heat and cold index categories are present in the simulations. Their distribution has some spatial features. All air quality categories are present in the domain, with dominance only of the O3 and PM10. Conclu-sions: It was found that Sofia is not so hot and air polluted place, but in some situations, people have to have some concerns when intend to be outdoors for a prolonged time.
ARTICLE | doi:10.20944/preprints202103.0234.v1
Subject: Medicine & Pharmacology, Allergology Keywords: chronic fatigue syndrome; fatigue; myalgic encephalomyelitis; melatonin; quality of life; sleep quality; zinc
Online: 8 March 2021 (16:00:25 CET)
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, multisystem, and profoundly debilitating condition, probably of multifactorial etiology. No effective approved drugs are currently available for its treatment. Several studies have proposed symptomatic treatment with melatonin and zinc supplementation in chronic illnesses; however, little is known about the synergistic effect of this treatment on fatigue-related symptoms in ME/CFS. The primary endpoint of the study was to assess the effect of oral melatonin plus zinc supplementation on fatigue in ME/CFS. Secondary measures included participants’ sleep disturbances, anxiety/depression, and health-related quality of life. A proof-of-concept, 16-week, randomized, placebo-controlled, double-blind trial was conducted in 50 ME/CFS patients assigned to receive either oral melatonin (1 mg) plus zinc (10 mg) supplementation (n = 24) or matching placebo (n = 26) once daily. Endpoint outcomes were evaluated at baseline and then reassessed at 8 and 16 weeks of treatment and 4 weeks after treatment cessation, using self-reported outcome measures. Treatment was safe and well-tolerated. The most relevant results were the significant reduction in the perception of physical fatigue in the active group at the final follow-up versus placebo (p < 0.05), and the significant improvement in the physical component summary at all follow-up visits in the experimental group. Our findings suggest that oral melatonin plus zinc supplementation for 16 weeks is safe and potentially effective in reducing fatigue and improving the quality of life in ME/CFS. This clinical study was registered on ClinicalTrials.gov (NCT03000777).
ARTICLE | doi:10.20944/preprints202102.0189.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: image quality assessment; image databases; superpixels; color image; color space; image quality measures
Online: 8 February 2021 (11:11:47 CET)
Objective Image Quality Assessment (IQA) measures are playing an increasingly important role in the evaluation of digital image quality. New IQA indices are expected to be strongly correlated with subjective observer evaluations expressed by MOS/DMOS scores. One such recently proposed index is the SuperPixel-based SIMilarity (SPSIM) index, which uses superpixel patches instead of the rectangular pixel grid.The authors in this paper have been proposed three modifications of SPSIM index. For this purpose, the color space used by SPSIM was changed and the way SPSIM determines similarity maps was modified using methods derived from the algorithm for computing the MDSI index. The third modification was a combination of the first two. These three new quality indices were used in the assessment process. The experimental results obtained on many color images from five image databases demonstrated the advantages of the proposed SPSIM modifications.
ARTICLE | doi:10.20944/preprints202104.0787.v4
Online: 3 October 2022 (12:14:56 CEST)
Hospital bed shortage is a worldwide concern. Beds unavailability has caused elective surgery cancellations, at our hospital peaking in spring 2016 at over 50%. This is often due to difficult patient step-down from intensive care (ICU) and high-dependency units (HDU). In our general/digestive surgery service admitting approximately 1000 patients yearly, ward rounds were run on a consultant firm basis. We report a quality improvement (ISRCTN13976096) introducing in our service a structured daily multi-disciplinary board round framework (SAFER Surgery R2G) adapted from the “SAFER patient flow bundle” and the "Red to Green days” approaches to enhance flow, comparing the previous year to 2017, when our framework was applied for 12 months.We used a Plan-Do-Study-Act (PDSA) methodology. Our intervention consisted in 1) systematic communication of the key care plan after the afternoon ward rounds to the nurse in charge; 2) 30’ 10AM Monday-to-Friday multidisciplinary board rounds, attended daily by the senior-team and weekly by hospital and site managers, revising the key care plan aiming at safe, early discharges, assessing the appropriateness of each inpatient day and tackling any cause of delay. We measured patient flow by average length of stay (LOS), ICU/HDU step-downs and operation cancellations count, monitoring safety through early 30-day readmissions. Compliance was assessed by board round attendance and staff satisfaction rate surveys.After 12 months (PDSA 2, N=1032), LOS significantly decreased from 7.2(±8.9) to 6.3(±7.4) days (p=0.003); ICU/HDU bed step-down flow increased by 9.3% from 345 to 375 (p=0.197), surgery cancellations dropped from 38 to 15 (p=0.100). 30-day re-admissions increased from 0.9% (N=9) to 1.3% (N=14)(p=0.390). Average cross-specialty attendance was 80%. Satisfaction rates were >75%, regarding enhanced teamwork and faster decisions.The SAFER Surgery R2G framework has shown an increase in patient flow in the context of an enhanced multidisciplinary approach, requiring senior staff commitment to remain sustainable.
ARTICLE | doi:10.20944/preprints202202.0356.v1
Online: 28 February 2022 (11:06:26 CET)
IT auditing quality has been defined by results obtained in the process. Meanwhile, multiple studies have been done to enhance it therefore, it continues to be a topic interest and research so it is worth mentioning that its quality relies on trained competent auditors and experts able to develop a process correctly, adapting to clients and to manage auditing inherent risks According to results from the IT audit, low quality and security levels have been identified in terms of the human, technical and contextual factors, affecting audit quality. The objective of this investigation is to identify metrics and to determine their own corresponding factor applying an exploratory type of research. In order to achieve such aim, a targeted survey was designed and implemented at the Institute of Internal Auditors of Ecuador since they have the knowledge and expertise in the field. A factor analysis statistics technique was applied to data gathered to verify that it relates to the identified factors as dimensions are reduced, thus the most impacting metrics may assess the quality of IT audits. Analysis results yielded a mean score for each one of the assessed metrics, concluding that the technical factor is the most significative since it relates roles and task performance during the auditing process as well as control proce-dures. Finally, most auditing quality-related issues are mainly the outcome of an inferior management auditing process, therefore it is crucial that collegiate groups and professionals in the field validate the auditing process.
ARTICLE | doi:10.20944/preprints202201.0424.v1
Online: 27 January 2022 (17:01:13 CET)
While maintenance dredging of port access channels is often required to maintain navigability, it can result in increased turbidity, sediment plumes, and associated reductions in water quality. Unoccupied aircraft systems (UAS, or drones) are increasingly applied to study water quality due to their high spatial and temporal resolutions. In this study, we investigated the use of drone imagery to monitor turbidity in the Morehead City Harbor, North Carolina, USA, during channel maintenance by hopper dredge. Drone flights were conducted concurrently with in-situ sampling during active dredging and post-dredging. Multispectral drone images were radiometrically calibrated, converted to reflectance and then turbidity using two separate processing methods and a single-band (red; 620nm-700nm) generic turbidity retrieval algorithm, and then compared to in-situ measurements. The method of using average reflectance to retrieve a single turbidity measurement per drone image produced agreeable results when compared to the in-situ measurements (R2 = 0.84). This method was then used to generate turbidity maps and extract surface plumes. While this could be considered a limited validation, the results indicate that realistic values can be obtained from drone imagery for low and high turbidity concentrations (1-72 FNU), making drones a viable option for monitoring surface turbidity associated with dredging.
REVIEW | doi:10.20944/preprints202105.0326.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: organic; conventional; potato; quality; disease
Online: 14 May 2021 (11:44:40 CEST)
Interest in organic foods is increasing at a moment when humanity is facing a range of health challenges including the concern that some conventionally produced foods may pose possible adverse effects on human and livestock health. With the increasing human population, intensive production is increasingly trending towards high-input systems that aim to close yield gaps, increase crop yields, and develop new crop varieties with higher yield potential and tolerance to biotic and abiotic stresses, all within the context of incorporating specific traits to satisfy consumer demand. Potato (Solanum tuberosum L.) is one of the most consumed foods under different cultural diets, however its production faces some challenges related to soilborne diseases, marketable yield and quality, sugars and dry matter content of the produced tubers, tuber content in terms of nitrate, minerals, vitamins, bioactive compounds and antioxidants, and consumer appreciation regarding the sensory characteristics of tubers and processed products. Different studies have been investigating some of these challenges, with sometimes straightforward and sometimes connflicting results. This variability in research results indicates the general non-transferability of the results from one location to another under the same management practices in addition to differences in plant material. This review compares some characteristics of raw or boiled potato and processed products from potato tubers grown organically and conventionally. Ideally, such information may be of benefit in decision making by consumers in their dietary choices, by potato growers in their selection of crop management practices, and by scientists looking at potential areas for future research on potatoes.
Subject: Medicine & Pharmacology, Allergology Keywords: Client; Satisfaction; Quality; Nursing Services
Online: 2 April 2021 (11:11:18 CEST)
Client or patient satisfaction is a very important indicator in determining service quality, patient satisfaction with various factors, but the main determining factor for patient satisfaction is the nurse, because nurses are medical personnel who are always near the patient and almost approaching the treatment that the client receives always involves the nurse. In it, therefore, nursing services, namely in the form of nursing care, are important to penetrate patient satisfaction. The purpose of this paper is to determine the effect of the quality of nursing services in increasing patient satisfaction. The method used in this research was a literature study which is analyzed from 25 articles searched through Google Scholar and Pubmed and selected based on indexes, namely Scopus, Sinta 1, and 2 and the topics discussed. The results showed that if the quality of service of nursing or nursing care can significantly increase patient satisfaction.
ARTICLE | doi:10.20944/preprints202012.0254.v1
Online: 10 December 2020 (12:27:31 CET)
Background: There is an upsurge in the consumption of chicken meat leading to a high influx of imported frozen chicken parts into the Ghanaian markets with little information on their microbial qualities. This study examined the microbial quality of imported frozen chicken parts from three major import countries (USA, the Netherlands and Brazil) into the Kumasi Metropolis. Methods: A total of 45 chicken meat parts of 15 thighs, wings and backs from wholesale cold stores market in the Kumasi Metropolis were randomly sampled for laboratory examinations. A ten-fold serial dilution was performed on each homogenized chicken parts to determine microbiological quality using Plate Count Agar , MacConkey Agar (MCA), Mannitol Salt Agar (MSA) and Desoxycholate Citrate Agar (DCA) for the total viable count (TVC), total coliform count (TCC), Staphylococcus and Salmonella spp counts respectively incubated at 37oC for 48 hours. Sabouraud Dextrose Agar (SDA) was used for fungal counts. We identified bacterial and fungal isolates using appropriate laboratory and biochemical tests. Descriptive data analysis was carried using SPSS-IBM version 16. Results: Mean TVCs of 5.93, 5.98 and 6.14 log10cfu/g were recorded for frozen chicken meats from the USA, the Netherlands and Brazil respectively. Means TCCs of 6.14, 5.93 and 5.98 log10cfu/g were obtained for chicken meats from Brazil, USA and the Netherlands respectively. Staphylococcus spp. (35.4%), E. coli (26.2%), Salmonella spp. (24.6%), and Klebsiella spp. (13.8%) were isolated with Aspergillus spp (33.3%), Rhizopus spp (27.3%), Penicillin spp (24.2%), and Cladosporium spp (15.2%). Chicken thighs, backs and wings recorded 46.2%, 29.2% and 24.6% bacterial contaminants in this order. Bacterial isolates of 49.2%, 28.8% and 22.0% were recorded in frozen chicken meat products from Brazil, the Netherlands USA respectively. Conclusion: The results suggest that imported frozen chicken meats into the Ghanaian market have moderate quality with potential pathogens such as E. coli and Salmonella spp.
Online: 12 July 2020 (15:14:30 CEST)
The PACS (Picture Archiving and Communication System) market is heterogenous with dozens of PACS providers having deployed installations in healthcare facilities. The DICOM query and retrieve interfaces provided by PACS have multiple variations, related to the implemented SOP (Service Object Pair) Class UID (Unique Identifier), transfer syntaxes, extended negotiations, matching attributes and matching types. These variations make any integration of a new DICOM consumer with a PACS complex and time consuming. As there is no collective information describing the various PACS query and retrieve capabilities, application developers and healthcare facilities lack a method to evaluate the PACS capabilities and classify its functionalities. GE designed a method to evaluate the PACS capabilities in terms of query retrieve functionalities. Our aim is to analyze several PACS in test and production environments, using our method to provide the DICOM object consumers a macroscopic knowledge of query/retrieve capabilities of PACS functionalities and its different variations. Our evaluation can also be used by PACS and VNA (Vendor Neutral Archive) developers to evaluate their query/retrieve capabilities, for quality improvement purpose.
ARTICLE | doi:10.20944/preprints202005.0125.v1
Online: 7 May 2020 (13:17:59 CEST)
Background: Accreditation is a qualitative assessment aimed at technical-professional quality, but above all, at organizational and measurable aspects through process and outcome checks. Method: There are few references in the literature relating to the accreditation and improvement of the quality and safety of care and treatment in the field of primary care. Clinical Governance must also be applied and certified in the field of primary care. Results: An accreditation system for general medicine is proposed based on a new dynamic model and implement that meets different requirements and assessed on the basis of indicators. Discussion: In the current Italian health system, accreditation of health structures is addressed only to public hospitals and private structures and to providers of services and services, however primary care. GPs / PLS do not have quality and safety guarantee systems or models or systems or public or private accreditation certifications with the SSR and SSN. Conclusion: Given the fundamental importance in the NHS of primary care of MG / PLS as the main and fundamental provider of services to the patient in all his socio-welfare and clinical needs, it is considered essential to think and implement an accreditation system extended to the territorial general practice as already present and in place for all affiliated and provider structures on behalf of the NHS.
ARTICLE | doi:10.20944/preprints201709.0130.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: Wikipedia; information quality; WikiRank; DBpedia
Online: 26 September 2017 (15:34:18 CEST)
Despite the fact that Wikipedia is often criticized for its poor quality, it continues to be one of the most popular knowledge base in the world. Articles in this free encyclopedia on various topics can be created and edited in about 300 different language versions independently. Our research showed that in language sensitive topics quality of information can be relatively better in the relevant language versions. However, in most cases it is difficult for the Wikipedia readers to determine the language affiliation of the described subject. Additionally, each language edition of Wikipedia can have own rules in manual assessing of the content quality. This makes automatic quality comparison of articles between various languages a challenging task. The paper presents results of relative quality and popularity assessment of over 28 million articles in 44 selected language versions. In addition, a comparative analysis of the quality and popularity of articles in some topics was conducted. The proposed method allows to find articles with information of better quality that can be used to automatically enrich other language editions of Wikipedia.
ARTICLE | doi:10.20944/preprints201704.0031.v1
Online: 5 April 2017 (18:09:25 CEST)
Models come in different forms: visual, arithmetic, mental, physical. The most common type of model is arguably the mental model, which people use to view and interpret the world. A model can be described as a representation of a problem or a situation – a simplified representation. The process of building or developing a model is called modeling. A model once developed by the modeller, can be ‘owned’ by a manager or decision maker. The ideal is to make the model an extension of the user’s ability to think about and analyse problems or situations. When used properly – taking into consideration its limitations – an economic model for a project can provide insight for decision makers, when making the crucial decision to approve a project. An economic model for a liquefied natural gas (LNG) project is shown as an example.
ARTICLE | doi:10.20944/preprints202103.0016.v1
Subject: Physical Sciences, Other Keywords: keyword 1; Hapkido 2; Service Quality 3; Quality on Exercise Continuation 4; Recommendation Intentions
Online: 1 March 2021 (13:37:51 CET)
This research analyzed the impact of quality of service as perceived by Hapkido students on their exercise continuation and recommendation intentions. It also identified the measures to reduce the rate of student dropout, strengthen competitiveness, and create more efficient marketing strategies for consumer patterns that are rapidly diversifying Hapkido. A questionnaire survey method was conducted with 300 middle and high school students aged 14–19 years having Hapkido training of three months to two years in Incheon and Bucheon during March–April 2019. Frequency, factor, reliability, correlation, and standard multiple regression analyses were conducted on the surveyed data. The conclusions are as follows. First, considering the impact of service quality on exercise continuation intention, service quality positively affects reliability, personification, and perceptual openness; in terms of possibility, it positively affects typicality, personification, and perceptual openness; and in terms of reinforcement, it positively affects reliability and perceptual openness. Second, examining the impact of service quality on recommendation intention positively affects reliability, personification, and perceptual openness. Third, exercise continuation intention positively affects recommendation intention.
REVIEW | doi:10.20944/preprints202009.0003.v1
Subject: Life Sciences, Other Keywords: polyphenols; reproduction; phytoestrogens; ovary function; sirtuin; testis function; spermatozoa; cryopreservation; sperm quality; oocyte quality
Online: 1 September 2020 (09:55:01 CEST)
Resveratrol is one of the most investigated natural polyphenolic compounds and is contained in more than 70 types of plants and in red wine. The widespread interest in this polyphenol derives from its antioxidant, anti-inflammatory and anti-aging properties. Several studies have established that resveratrol regulates animal reproduction. However, the mechanisms of action and the potential therapeutic effects are still unclear. This review aims to clarify the role of resveratrol in the male and female reproductive functions, with a focus on animals of veterinary interest. In the female, resveratrol has been considered a phytoestrogen due to its capacity to modulate ovarian function and steroidogenesis via sirtuins, SIRT1, in particular. Resveratrol has also been used to enhance aged oocyte quality, and as a gametes cryo-protectant with mainly antioxidant, and anti-apoptotic effects. In the male, resveratrol enhanced testes function and spermatogenesis through activation of AMPK pathway. Furthermore, resveratrol has been supplemented to semen extenders improving the preservation of sperm quality. In conclusion, resveratrol has potentially beneficial effects for ameliorating ovarian and testes function. However, due to unclear data, further studies are necessary to consolidate these findings.
ARTICLE | doi:10.20944/preprints201806.0185.v1
Subject: Medicine & Pharmacology, Nursing & Health Studies Keywords: mHealth; mobile data collection; data quality; data quality assessment framework; Tuberculosis control; developing countries
Online: 12 June 2018 (10:34:33 CEST)
Background Increasingly, healthcare organizations are using technology for the efficient management of data. The aim of this study was to compare the data quality of digital records with the quality of the corresponding paper-based records by using data quality assessment framework. Methodology We conducted a desk review of paper-based and digital records over the study duration from April 2016 to July 2016 at six enrolled TB clinics. We input all data fields of the patient treatment (TB01) card into a spreadsheet-based template to undertake a field-to-field comparison of the shared fields between TB01 and digital data. Findings A total of 117 TB01 cards were prepared at six enrolled sites, whereas just 50% of the records (n=59; 59 out of 117 TB01 cards) were digitized. There were 1,239 comparable data fields, out of which 65% (n=803) were correctly matched between paper based and digital records. However, 35% of the data fields (n=436) had anomalies, either in paper-based records or in digital records. 1.9 data quality issues were calculated per digital patient record, whereas it was 2.1 issues per record for paper-based record. Based on the analysis of valid data quality issues, it was found that there were more data quality issues in paper-based records (n=123) than in digital records (n=110). Conclusion There were fewer data quality issues in digital records as compared to the corresponding paper-based records. Greater use of mobile data capture and continued use of the data quality assessment framework can deliver more meaningful information for decision making.
ARTICLE | doi:10.20944/preprints202110.0325.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Pollution in Lakes; Quality assessment; Water and metal quality index; Metal pollution index; Correlation analysis
Online: 22 October 2021 (10:09:36 CEST)
With this article, impact of effluent mixed water with the quality of the Mansagar Lake has been established by evaluating the physico-chemical parameters and the heavy-metal contents experimentally. The process of calculating water quality and the metal pollution quality indices is also explained in brief with respect to selected sample locations and varied environmental conditions (Pre- and Post-Monsoon season). Distribution trends of Pearson‘s correlation factor have also been discussed to establish their relation among the physico-chemical parameters and the heavy-metal contents for varied environmental conditions. In the end, detailed discussion on observations made during this study and useful recommendations are also elaborated in details. With this article, we intend to present a document for better understanding of the water quality of this lake in view of futuristic management strategies to be adopted to maintain it heritage values.
ARTICLE | doi:10.20944/preprints202106.0569.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Sleep quality; Chronic pain; Temporomandibular disorder; Pittsburgh Sleep Quality Index; STOP-Bang; Epworth Sleepiness Scale
Online: 23 June 2021 (11:11:14 CEST)
Objectives: This study aimed to investigate and compare sleep quality between patients with chronic temporomandibular disorder and healthy controls, and to analyze the association of sleep quality with disease characteristics, obstructive sleep apnea risk factors, and excessive daytime sleepiness. Methods: Chronic temporomandibular disorder patients (n=503) and 180 age- and sex-matched healthy controls were included, who completed well-organized clinical report and answered questions on sleep quality (Pittsburgh Sleep Quality Index), sleep apnea risk factors (STOP-Bang questionnaire), and excessive daytime sleepiness (Epworth sleepiness scale). Results: Mean global Pittsburgh Sleep Quality Index scores were significantly higher in the patients (6.25±2.77) than in healthy controls (6.25±2.77) (p<0.001). Poor sleep was significantly more prevalent in the patient group (56.9%) than in healthy controls (22.2%) (p<0.001). Compared with healthy controls, chronic temporomandibular disorder patients had a higher likelihood of obstructive sleep apnea. (STOP-Bang total score ≥3; 7.2% vs. 16.1%; p<0.01) and higher excessive daytime sleepiness (Epworth sleepiness scale score ≥10; 12.8% vs. 19.7%; p<0.05). Age (odds ratio=2.551; p<0.001), female sex (odds ratio=1.885; p=0.007), total Epworth sleepiness scale score (odds ratio=1.839; p=0.014), and headache attributed to temporomandibular disorder (odds ratio=1.519; p=0.049) were the most powerful predictors of poor sleep (global Pittsburgh Sleep Quality Index score ≥5) in chronic temporomandibular disorder patients. Conclusion: Chronic temporomandibular disorder patients had sleep quality impairment. Various factors, including peripheral and central factors, affect the patient's sleep quality. Therefore, in addition to sleep quality and sleep-related problems, the underlying central mechanism for poor sleep quality should be assessed when treating chronic temporomandibular disorder patients.
ARTICLE | doi:10.20944/preprints202106.0041.v1
Subject: Earth Sciences, Atmospheric Science Keywords: air quality; air pollution measurements; electrochemical sensors; low-cost sensors; AQI (Air Quality Index); Athens
Online: 1 June 2021 (15:08:39 CEST)
Most people living in Europe's cities are still exposed to levels of air pollution deemed harmful by the World Health Organization. In the modern world, air pollution is the foremost concern because of its impact in human health and economy. This strong connection appears gaining a lot of concern, driven by new installed low-cost electrochemical sensors monitoring systems. Highly accuracy, real-time monitoring, daily and yearly statistics, data access from experts or simple users, low-cost equipment and forecasting needs, enforce the market to develop new air quality monitoring systems using advanced technologies and protocols. In this study, a comparison via low-cost electrochemical sensors and of static, fixed site measurement monitoring station, is taking place in Athens, Greece, along with the data quality and Air Quality Index (AQI) including data accuracy and quality of data concerning adverse health effects due to air pollution. The findings presented in this work, relate to different flexible and affordable alternatives adopted during the evaluation and calibration of low-cost gas sensors for the monitoring. The significance of the positive results is particularly useful, especially considering the founding for interference, environmental conditions affections and air quality information including indexes and health recommendations for a specific location.
ARTICLE | doi:10.20944/preprints202010.0637.v1
Subject: Keywords: Mean Opinion Score (MOS); Quality of Experience (QoE); bandwidth; bandwidth cost; Quality of Service (QoS)
Online: 30 October 2020 (12:55:01 CET)
Quality of Service (QoS) metrics deal with network quantities, e.g. latency and loss, whereas Quality of Experience (QoE) provides a proxy metric for end-user experience. Many papers in the literature have proposed mappings between various QoS metrics and QoE. This paper goes further in providing analysis for QoE versus bandwidth cost. We measure QoE using the widely accepted Mean Opinion Score (MOS) rating. Our results naturally show that increasing bandwidth increases MOS. However, we extend this understanding by providing analysis for internet access scenarios, using TCP, and varying the number of TCP sources multiplexed together. For these target scenarios our analysis indicates what MOS increase you get by further expenditure on bandwidth. We anticipate that this will be of considerable value to commercial organizations responsible for bandwidth purchase and allocation.
ARTICLE | doi:10.20944/preprints202112.0196.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: Speech Rehabilitation; Speech Quality Assessment; LSTM
Online: 13 December 2021 (10:10:36 CET)
The article considers an approach to the problem of assessing the quality of speech during speech rehabilitation as a classification problem. For this, a classifier is built on the basis of an LSTM neural network for dividing speech signals into two classes: before the operation and immediately after. At the same time, speech before the operation is the standard to which it is necessary to approach in the process of rehabilitation. The metric of belonging of the evaluated signal to the reference class acts as an assessment of speech. An experimental assessment of rehabilitation sessions and a comparison of the resulting assessments with expert assessments of phrasal intelligibility were carried out.
ARTICLE | doi:10.20944/preprints202108.0381.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: quinoa; genotype; nutritional traits; seed quality
Online: 8 September 2021 (12:37:08 CEST)
Exploiting the relationship between the nutritional properties of seeds and the genetic background, constitutes an essential analysis which contributes to broadening our knowledge regarding the control of the nutritional quality of seeds or any other edible plant structure. This constitutes an important aspect when aiming at improving the nutritional characteristics properties of crops, including those of Chenopodium quinoa Willd (quinoa) which is intended to be one of the main nutrient sources ensuring food security worldwide. Changes in the nutritional properties of quinoa seeds due to the influence exerted by the environment, the genotype, or their interaction, have been already described in previous works, but there is an important limitation in the analyses carried out, including the outcomes that can be translated into agronomical practices by which quality can be improved selecting the most adequate genotype. In the present study, several seed nutritional-related parameters from fifteen quinoa cultivars grown in a particular environmental context were analyzed aiming at targeting compounds that can be determinants of seed quality. Important agronomical and nutritional differences were found among cultivars such as distinct mineral or protein contents and seed viability. More importantly, our analyses revealed key correlations between seed quality-related traits in some cultivars, including those that relate yield and antioxidants or the germination rate. These results highlight the importance of considering the genotypic variation in quinoa when selecting improved quinoa varieties with the best nutritional characteristics for new cultivation environments.
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.
ARTICLE | doi:10.20944/preprints202101.0205.v1
Subject: Life Sciences, Biochemistry Keywords: communication; childbirth; satisfaction; quality of care
Online: 11 January 2021 (17:46:12 CET)
The study aims to identify the difference in communication needs of women giving birth and women during puerperium. An additional goal includes the analysis of the experience and communication needs through the context of a woman's approach to childbirth. The study is a prospective, cross-sectional, self-report survey. 521 women between 5 and 10 days after birth participated in the study. Women perceived information provided by the medical staff as the most helpful aspect of verbal communication both during labour and puerperium. Maintaining eye contact with the medical staff was perceived as the most helpful aspect of non-verbal communication. Women were more satisfied with communication during labour and birth than in the maternity ward and those after non-instrumental childbirth were more satisfied with communication compared to the instrumental birth group. Women perceiving childbirth as the natural, physiological process considered verbal and non-verbal communication during and after childbirth as less helpful than women perceiving birth as more risky and requiring interventions. The results of the study emphasize the importance of verbal and non-verbal communication during birth and puerperium and different communication needs during labour and early postpartum. It also showed that women who perceive labour as a physiological process seem to be less dependent on the communication with the medical staff than women who accept medical interventions during labour and birth as necessary.
ARTICLE | doi:10.20944/preprints201912.0060.v1
Subject: Keywords: mobile app, software quality anti-patterns
Online: 5 December 2019 (04:16:35 CET)
As the time passes the modification in technology world lead to the evaluation in mobile application as well. With evaluation in mobile industry it is an open challenge for software quality researcher that how to enhance software quality to meet the needs of changes? Quality assurance play a key role in differentiating good application from bed application. With the continuous evaluation of mobile application developing process should be quick and efficient to comply with user requirements and satisfaction. While the listed requirement leads to bad design choices known as antipatterns, which in turn affect the reliability of the code. A tool based method PAPRIKA is used in the proposed re-search to identify and monitor these antipatterns together with a two-step assessment model for software quality assurance and object oriented software quality matrix.
ARTICLE | doi:10.20944/preprints201911.0091.v1
Subject: Social Sciences, Organizational Economics & Management Keywords: 2030 Agenda; strategic planning; quality criteria
Online: 8 November 2019 (08:11:50 CET)
The UN’s 2030 Agenda brings new governance challenges to municipal environmental planning, both in large urban centres and in metropolitan peripheries. The opportunities of the new framework of action proposed by the United Nations (UN) and its integrative, global and transversal nature constitute advances from the previous models of municipal management based on the Local Agenda 21. This text provides evidence to apply quality criteria and validated instruments of participatory evaluation. These instruments have been built on the foundation of Evaluative Research, a scientific discipline that provides rigour and validity to those decisions adopted at a municipal level. A case study focused on a metropolitan area serves as a field of experimentation for this model of the modernization of environmental management structures at a local level. Details of the instruments, agents, priority decision areas, methodologies, participation processes and quality criteria are provided, as well as an empirically validated model for participatory municipal management based on action research processes and strategic planning that favours a shared responsibility across all social groups in the decision-making process and in the development of continuous improvement activities that are committed to sustainability. Finally, a critical comparison of weaknesses and strengths is included in light of the evidence collected.
ARTICLE | doi:10.20944/preprints201806.0123.v1
Subject: Social Sciences, Economics Keywords: sustainable; livelihood; policy; vulnerability; choice; quality
Online: 7 June 2018 (12:39:47 CEST)
This study aims to assess food security status of rural, peri-urban and urban households and role of socio-economic factors in ensuring food security. A survey was conducted to collect primary (quantitative) data from 630 respondents using proportionate sampling technique from Punjab, Pakistan. Cronbach’s Alpha reveals stability (>0.75) of data scale items. Using Dietary Intake Assessment (DIA), findings reveal urban households as highly food-secure whereas rural household as most vulnerable to food security at 2450kcal/day per person. Study indicates food price increase as the leading factor in preventing food security among households. Contrary, study identifies risk factors associated to food quality under the abundant availability and access as the new dimension to household food insecurity. Further, results of binary logit model show that socio-economic factors such as monthly income, total number of earners, education of household head and access to market are positively related with food security status whereas, social isolation, volatility in food prices and risk factors in food quality are negatively related with household food security. Therefore, study proposes educational orientation and entrepreneurial development as sustainable solution to ensure food security among masses. Besides, further country level researches are advised to deep delve the mounting menace of food security.
ARTICLE | doi:10.20944/preprints201805.0123.v1
Online: 8 May 2018 (06:30:56 CEST)
The air quality monitoring network in Alaska is currently limited to ground-based observations in urban areas and national parks leaving a large proportion of the state unmonitored. The use of MODIS aerosol optical depth (AOD) to estimate ground-level particulate pollution concentrations has been successfully demonstrated around the world, and could potentially be used in Alaska. In this work, MODIS AOD measurements at 550 nm were validated against AOD derived from AERONET ground-based sunphotometers in Barrow and Bonanza Creek to determine if MODIS AOD from the Terra and Aqua satellites could be used to estimate ground-level particulate pollution concentrations. The MODIS AOD was obtained from MODIS collection 6 using the dark target Land and Ocean algorithms from 2000 to 2014. MODIS data could only be obtained between the months of April and October; therefore, it could only be validated for those months. Individual and combined Terra and Aqua MODIS data were considered. The results showed that MODIS collection 6 products at 10 km resolution for Terra and Aqua combined are not valid over land but are valid over the ocean. On the other hand, the individual Terra and Aqua MODIS collection 6 AOD products at 10 km resolution are valid over land individually but not when combined. Results also suggest the MODIS collection 6 AOD products at 3 km resolution are valid over land and ocean and perform better over land than the 10-km product. These findings indicate that MODIS collection 6 AOD products can be used quantitatively in air quality applications in Alaska during the summer months.
ARTICLE | doi:10.20944/preprints201711.0060.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: ECG quality assessment; complexity; entropy; ROC
Online: 9 November 2017 (05:47:22 CET)
We compared performance of a novel encoding Lempel-Ziv complexity (ELZC) with approximate entropy (ApEn), sample entropy (SmpEn) and permutation entropy (PerEn) as nonlinear metric to assess ECG quality. Firstly to compare performance of discerning randomness and inherent nonlinear properties within time series, this study calculated the aforementioned four nonlinear complexity values on several typical artificial time series i.e., Gauss noise, two kinds of noisy time series, two kinds of Logistic series and periodic series, respectively. Then for analyzing sensitivity of the aforementioned four complexity methods to content level of different types noise within ECG recordings, we investigated variation trend of ELZC, ApEn, SmpEn and PerEn in several synthetic ECG recordings containing different types noise (i.e., baseline wander, muscle artefacts, electrode motion, power line and mixed noise) and different signal noise ratios (i.e., 15, 10, 5, 0, −5 and −10 dB). Finally, the four complexity methods were employed to classify the quality of real ECG recordings from the PhysioNet/Computing in Cardiology Challenge 2011 (CINC 2011) of the MIT databases, then receiver operating characteristic curves (ROC) and their corresponding area under curve (AUC) were yielded. The results showed ELZC could not only distinguish randomness and chaotic within time series but also reflect content level of noise within time series, and the highest AUC of PerEn, ELZC, SmpEn and ApEn were 0.850, 0.695, 0.474 and 0.461, respectively. The results demonstrated PerEn and ELZC were more effectively than ApEn and SmpEn for assessing ECG quality.
ARTICLE | doi:10.20944/preprints201704.0065.v1
Online: 11 April 2017 (17:32:40 CEST)
Local air quality is a major concern for the population regularly exposed to high levels of air pollution. The airport, mainly due to its aircraft engines activities during taxiing and take off, is often submitted to heterogeneous but important concentrations of NOx and PM. The study suggests an innovative approach to determine the air traffic impact on air quality at the scale of the airport, its runways and terminals, in order to be able to locate the persistent high concentrations spots. The pollutants concentrations at 10 m resolution and 1 s time step are calculated in order to identify the most affected areas of an airport platform. A real day of air traffic on a regional airport is simulated, using real data as aircraft trajectories (from radar streams). In order to estimate the aircraft emissions, the Air Transport Systems Evaluation Infrastructure (IESTA) is used. Regarding local air quality, IESTA relies on the non-hydrostatic meso-scale atmospheric model Meso-NH using grid-nesting capabilities with 3 domains, for this study. The detailed cartography of the airport distinguishes between grassland, parking and terminals, allowing to compute exchanges of heat, water and momentum between the different types of surfaces and the atmosphere as well as the interactions with the building using a drag force. The dynamic parameters like wind, temperature, turbulent kinetic energy and pollutants concentration are computed at 10 m resolution over the 2 × 4 km airport domain. The pollutants are considered in this preliminary study as passive tracers, without chemical reactions. This preliminary study aims at proving the feasibility of high scale modelling over an airport with state of the art physical models.
ARTICLE | doi:10.20944/preprints201710.0016.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: citizen science; volunteered geographical information; metadata; data quality; quality assurance; scientific workflow; provenance; metaquality; open data
Online: 3 October 2017 (13:52:29 CEST)
Environmental policy involving citizen science (CS) is of growing interest. In support of this open data stream, validation or quality assessment of the CS data and their appropriate usage for evidence-based policy making, needs a flexible and easily adaptable data curation process ensuring transparency. Addressing these needs, this paper describes an approach for automatic quality assurance as proposed by the Citizen OBservatory WEB (COBWEB) FP7 project. This approach is based upon a workflow composition that combines different quality controls, each belonging to seven categories or ‘pillars’. Each pillar focuses on a specific dimension in the types of reasoning algorithms for CS data qualification. These pillars attribute values to a range of quality elements belonging to three complementary quality models. Additional data from various sources, such as Earth Observation (EO) data, are often included as part of the inputs of quality controls within the pillars. However, qualified CS data can also contribute to the validation of EO data. Therefore, the question of validation can be considered as ‘two sides of the same coin’. Based on an invasive species CS study, concerning Fallopia japonica (Japanese knotweed), the paper discusses the flexibility and usefulness of qualifying CS data, either when using an EO data for the validation within the quality assurance process, or validating an EO data product that describes the risk of occurrence of the plant. Both validation paths are found to be improved by quality assurance of the CS data. Addressing the reliability of CS open data, issues and limitations of the role of quality assurance for validation, due to the quality of secondary data used within the automatic workflow, are described, e.g. error propagation, paving the route to improvements in the approach.
ARTICLE | doi:10.20944/preprints202201.0185.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Air quality; fine particulate matter; primary schools; building ventilation; environmental inequality; research grade sensors; indoor air quality
Online: 13 January 2022 (10:28:35 CET)
Every day around 93% of children under the age of 15 (1.8 billion children) breathe outdoor air that is so polluted it puts their health and development at serious risk. Due to the pandemic, however, ventilation of buildings using outdoor air has become an important safety technique to prevent the spread of COVID-19. With the mounting ev-idence suggesting that air pollution is impactful to human health and educational out-comes, this contradictory guidance may be problematic in schools with higher air pol-lution levels, but keeping kids COVID-19 free and in school to receive their education is now more pressing than ever. To understand if all schools in an urban area are ex-posed to similar outdoor air quality and if school infrastructure protects children equally indoors, we installed research grade sensors to observe PM2.5 concentrations in indoor and outdoor settings to understand how unequal exposure to indoor and out-door air pollution impacts indoor air quality among high- and low-income schools in Salt Lake City, Utah. Based on this approach, we found that during atmospheric inver-sions and dust events, there was a lag ranging between 35 to 73 minutes for the out-door PM2.5 concentrations to follow a similar temporal pattern as the indoor PM2.5. This lag has policy and health implications and may help to explain the rising concerns re-garding reduced educational outcomes related to air pollution in urban areas. These data and resulting analysis show that poor air quality may impact school settings, and the potential implications with respect to environmental inequality.
ARTICLE | doi:10.20944/preprints202207.0207.v1
Subject: Engineering, Civil Engineering Keywords: Accelerated Curing; Curing Regime; CUSUM; Quality Control
Online: 14 July 2022 (09:14:00 CEST)
Quality monitoring (QM) with CUSUM system can result in potential economy in RMC through optimal control of target strength (by avoiding overdesign) on the one hand and through reduction of producers’ risk against rejection by the client on the other. To overcome the problems associated with the conventional 28-day compressive strength test, correlations are established between accelerated and the standard 28-day cube strength to predict the 28-day strength from the early age strength itself. This paper tried to demonstrate the lack of reliability of single correlation itself along the production time of RMC. The correlations vary with W/C as well as with type of cement. Hence it is demonstrated that correlation is concrete specific. Further, it is also demonstrated that correlation established with specimens having wide variation in the batching may result in poor correlation. Through CUSUM plots of mean and range for cube strength obtained by Monte-Carlo simulation demonstrate the utility of prediction through such correlation in QM and a methodology for monitoring the correlation itself.
ARTICLE | doi:10.20944/preprints202201.0191.v1
Online: 13 January 2022 (13:56:33 CET)
The present research intents to study the evolution of the skin fatty acids and physiological disorders through cold storage in ‘Golden Delicious’ apples treated with 1-MCP and calcium. Harvested fruit were treated with calcium chloride (Ca), 1-MCP (MCP), Ca+MCP or no treatment (control) then subjected to cold storage at 0.5 ºC for 6 months. Fatty acids composition, Malondialdehyde (MDA) and the physiological disorders bitter pit (BP), superficial scald and diffuse skin browning (DSB) were measured at harvest and after storage plus 7 days shelf-life at room temperature ≈22 ºC. Palmitic acid decreased and linoleic acid increased through time, while oleic and stearic acids had few changes. Unsaturated/saturated fatty acids and MDA increased through time, despite Ca and Ca+MCP were related to lower MDA and lower BP and rotten fruit, after cold storage and shelf-life. In those treatments, the unsaturated/saturated fatty acids were higher, mainly due to higher linoleic acid and lower palmitic acids. Further research is needed to clarify the changes in membrane properties and the effect of some treatments in response to chilling injury through storage.
ARTICLE | doi:10.20944/preprints202110.0256.v1
Subject: Arts & Humanities, Other Keywords: Education; Mozambique; Quality; Development; Millennium Development Goals.
Online: 18 October 2021 (15:39:48 CEST)
In order to meet the Millennium Development Goals set forth by the United Nations’ Millennium Summit that took place in 2000, in New York, particularly in the area of education, the Mozambican Government decided that, from 2003 onwards, during their primary school formation, students should be passed automatically even if they do not have enough intellectual capacities that justify their progress. In fact, this decision was made during a period when there were many pupils being failed, due to various reasons. After more than 15 years of its implementation, this paper aims to analyzing the results acquired from this decision, from the point of view of the quality of education. This will be done taking into account the prevailing situation of education in Mozambique. Having considered these aspects, the paper will move on to presenting some of the challenges and opportunities that the country should consider in the area of education, as a way to bring about better outcomes and promote development, in the country.
Online: 4 October 2021 (17:37:19 CEST)
Phytophthora infestans (Mont.) de Bary causing potato late blight (LB) and potato virus Y (PVY), are serious constraints to cultivated potatoes causing important yield reduction, and phenotyping for resistance is challenging. Breeding operations for vegetatively propagated crops can lead to genotype mislabeling that in turn reduces the genetic gain. Low-density and low-cost molecular marker assessment for phenotype prediction and quality control stands as a viable option for breeding programs. We report here the development of Kompetitive Allele Specific PCR (KASP) markers for LB and PVY resistance, and for quality control assessment, and their routine use in different breeding populations. Two KASP markers for LB resistance and two for PVY Ryadg were validated with an estimated assay power ranging between 0.65 and 0.88. Developed QC KASP markers demonstrated the power of tetraploid calls in discriminating the breeding material, including full sibs and half sibs. The routine implementation of developed markers in a breeding program will allow a better allocation of resources and a precise characterization of the breeding material, leading to an increased genetic gain.
Online: 27 September 2021 (11:59:11 CEST)
Heat stress during the grain-filling period is the main abiotic stress factor limiting grain yield and quality in wheat (Triticum aestivum L.). In this study, 64 wheat genotypes were exposed to heat stress during reproduction caused by delayed sowing in two growing seasons. Grain yield, 1000 grain weight (GW), grain hardness (GH), and grain-quality related traits were investigated using wholemeal flour. Heat stress caused a significant decrease in GW through reducing starch content (SC) and a non-compensating rise in protein content (PC), and thereby resulted in lower yield. In addition, significant increases in flour water absorption (WA), Zeleny sedimentation volume (ZT), ash content (AC), lipid content (LC), loaf volume (LV), wet gluten content (WG), dry gluten content (DG), gluten index (GI), and amylopectin content (APC) were found following heat stress. In contrast, decreases in grain moisture content (MC) and amylose content (AMC) induced by heat stress were observed. The heat-tolerant genotypes were superior in grain yield, GW, SC, AMC, and MC. While the sensitive genotypes contained higher PC, LV, GI and AMP. A group of wheat genotypes characterized with a higher yield, AMC, GW, and SC as well as lower PC, WA, GH, ZT, and LV; and was found to be the most heat tolerant by principal component analysis. Decreases in the ratio of carbohydrates to proteins induced by heat stress, and lower protein content of normal grown wheat genotypes were observed. Therefore, lighter weight and smaller grains produce a smaller starchy endosperm with lower quality (less amylose) and higher grain protein content in heat stress compared to normal conditions. Heat stress caused by delayed sowing improves some of the baking-quality related traits. Whether this improvement in grain quality attributes will translate into better human health outcomes requires further investigation.
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/preprints202106.0223.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: Blockchain; Rice; Supply chain traceability; Quality control
Online: 8 June 2021 (12:34:45 CEST)
Rice is the grain feeds more than half of the world population. It is an important staple food provides twenty percent of the calories consumed worldwide. Food safety affects the health of consumers. Establishing an effective traceability system is one of the primary measures to protect rice quality and food safety. Blockchain-based traceability system has the characteristics of data tamper-proofing, decentralization, and co-governance. This paper proposed a rice traceability scheme based on blockchain technology that selects the critical nodes in the rice industry chain to construct a blockchain network to achieve transparent data sharing. It is meaningful for both enterprises and consumers. It can let enterprises get the real quality information of rice and related raw materials. Consumers can get the true information of rice and rice products to buy safe and healthy food. The scheme is proved feasible by simulating the traceability of the rice supply chain.
ARTICLE | doi:10.20944/preprints202105.0332.v1
Subject: Life Sciences, Biochemistry Keywords: kefir; alfalfa; silage; fermentation quality; microbial communities
Online: 14 May 2021 (13:13:37 CEST)
The present study has been one of the first attempts to thoroughly examine the effects of different kefir sources on fermentation characteristics, aerobic stability, and microbial communities of alfalfa silages. The effects of commercial kefir (CK) and homemade kefir culture (HK) applied with four different application doses (untreated control (CON), 5.0, 5.7, and 6.0 log cfu g-1) on wilted alfalfa and stored at an ambient temperature of 25-30 °C. After 45 days ensiling, fermentation characteristics and aerobic stability of silages were measured and bacterial diversity was investigated by 16S ribosomal RNA gene sequencing using GenomeLab™ GeXP platform. Both CK and HK accelerate more lactic acid production and reduced ammonia nitrogen concentration. Factor analysis of kefir sources suggest that the addition of kefir improves the aerobic stability of silages even the initial water soluble carbohydrate (WSC) content is inadequate via its antimicrobial effect on yeast and mould formation. Enterococcus faecium, Pediococcus pentosaceous, and Lactobacillus brevis were dominant bacterial species among the treated groups at silo opening while Lactobacillus plantarum and Lactobacillus brevis became dominant bacterial species after 7 days of aerobic exposure. In conclusion, application of kefir on alfalfa silages improves fermentation quality and aerobic stability even with low WSC content.
ARTICLE | doi:10.20944/preprints202104.0781.v1
Subject: Chemistry, Analytical Chemistry Keywords: Lactobacillus plantarum; Chinese sausage; antioxidation; flavour; quality
Online: 29 April 2021 (15:45:00 CEST)
Effects of Lactobacillus plantarum (L. plantarum) strain P3 and mutant strain P3-M2 with antioxidant properties on fermented sausage flavour via lipid and protein oxidation inhibition were investigated. The commerical strain was used to as positive control (control group). Results showed that P3 and P3-M2 had the ability of reducing lipid and protein oxidantion during fermentation. The increase of lipoxygenase activity and thiobarbituric acid reactive substances (TBARS) values were retarded. Metmyoglobin(MetMb) content relatively decreased significantly(p < 0.05), while sulfhydryl group contents were significantly higher than those in the control((p < 0.05). Futhermore, changes in protein bands were confrimed with the less protein oxidation with P3-M2 than P3 and the control. Additionally, strain P3 and P3-M2 significantly enhanced the type and relative content of esters after fermented (p < 0.05), indicating that strain P3 and P3-M2 contributed to the production of flavor substances. These results revealed that L. plantarum strains with antioxidant properties were a promising approach in inhibiting lipid and protein oxidation of chinese sausage, maintaining the stable natural structure of protein, simultaneously improve the quality of sausage and promote the sausage to form a better flavor.
ARTICLE | doi:10.20944/preprints202103.0329.v1
Subject: Engineering, Automotive Engineering Keywords: Ensilement; Grass Quality; Hyperspectral Reflectance; Predictive Models
Online: 12 March 2021 (08:02:49 CET)
A series of experiments were conducted to measure and quantify the yield, dry matter content, sugars content and nitrates content of grass intended for ensilement. These experiments took place in the East Midlands of Ireland during the Spring, Summer and Autumn of 2019. A bespoke sensor rig was constructed; included in this rig was a hyperspectral radiometer that measured a broad spectrum of reflected natural light from a circular spot approximately 1.2 metres in area. Grass inside a 50cm square quadrat was manually collected from the centre of the circular spot for ground truth estimation of the grass qualities. Up to 25 spots were recorded and sampled each day. The radiometer readings for each spot were automatically recorded onto a laptop that controlled the sensor rig, and ground truth measurements were made either on site or within 24 hours in a wet chemistry laboratory. The collected data was used to build Partial Least Squares Regression (PLSR) predictive models of grass qualities from the hyperspectral dataset and it was found that substantial relationships exist between the spectral reflectance from the grass and yield (r2 = 0.62), dry matter % (r2 = 0.54), sugar content (r2 = 0.54) and nitrates (r2 = 0.50). This shows that hyperspectral reflectance data contains substantial information about key grass qualities and can form part of a broader holistic data driven approach to provide accurate and rapid predictions to farmers, agronomists and agricultural contractors.
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/preprints202012.0342.v1
Subject: Social Sciences, Accounting Keywords: supply chain management; transport; sustainability; quality; innovation
Online: 14 December 2020 (14:03:54 CET)
The present article proposes a complete framework for Supply Chain Strategy (SCS) analysis that is adapted to the specific characteristics of the agrifood chain, thereby facilitating management of the former. As a specific case of analysis, the horticultural supply chain, originating in Spain and ending with the European consumer, is analyzed, taking as a reference the marketing companies at origin (mainly social economy companies, i.e.; cooperatives). In addition, a survey of marketing companies is conducted to possibly determine which explicit cooperative growth strategies may include horizontal and vertical collaboration relationships with other members of the chain. The aim is to analyze with whom the cooperative collaborates within the supply chain and the key points of such collaboration. A model analyzing the influence of collaboration on company performance is also considered. The results reveal that, in recent years, aspects related to quality and health have been surpassed and replaced by the concept of sustainability within a framework of collaboration with customers. In any case, it becomes evident that there is a need to expand collaboration within the chain by incorporating the supplier of the supplier, with the aim of making the chain more profitable.
ARTICLE | doi:10.20944/preprints202010.0284.v1
Subject: Biology, Anatomy & Morphology Keywords: rye; secalins; glutenins; chromosome rearrangements; dough quality
Online: 13 October 2020 (14:22:54 CEST)
A bread wheat line (N11) and a disomic 2D(2R) substitution triticale line have been crossed and backrossed four times. At each step electrophoretic selection for the seeds that possessed, simultaneously, the complete set of high molecular weight glutenin subunits of N11 and the two high molecular weight secalins of rye, present in the 2D(2R) line, was carried out. Molecular cytogenetic analyses of the BC4F5 generation have revealed that the selection carried out had produced a disomic addition line (2n=44). The pair of additional chromosomes consisted of the long arm of chromosome 1R (1RL) from rye fused with the satellite body of the wheat chromosome 6B. Rheological analyses revealed that the dough obtained by the new addition line had higher quality characteristics when compared with the two parents. The role of the two additional high molecular weight secalins, present in the disomic addition line, in influencing improved dough characteristics is discussed.
ARTICLE | doi:10.20944/preprints202008.0725.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: litchi; fruit bagging; bag colours; dates; quality
Online: 31 August 2020 (16:25:13 CEST)
Litchi orchards of 15 year age in Pantnagar were subjected to different fruit bagging treatments in study entitled “Impact of pre-harvest fruit bagging technology on growth and quality traits in litchi cv. Rose Scented under Indian prospective”. The combination includes white and pink polypropylene bags practiced on three dates i.e. 15, 25 and 30 days after fruit set and a control. Hence, study comprised of 7 treatment combination in total. The data of year 2017 and 2018 as well as pooled data revealed that T1 i.e. white polypropylene bags + bagging 15 days after fruit set was found to be promising in attributes such as fruit cracking (%) and Sun burn (%). T3 White Polypropylene bags + bagging 30 days after fruit set was found best for fruit Weight (g) and Acidity (%), T4 Pink Polypropylene bags + bagging 15 days after fruit set was found promising for TSS (0Brix), T6-Polypropylene Pink + 10th May (30 days after fruit set) was observed to be best for most of the desired attributes viz. Fruit breadth (mm), Yield (Kg/tree), Acidity (%), Anthocyanin (mg/100g), Fruit colour (visual), borer infestation (%) and B:C Ratio. However, fruits without bagging i.e. control were found to have inferior appearance and have maximum fruit cracking (%) and sun burn (%). Thus the bagging of litchi fruits with white polypropylene bags 15 days after fruit set resulted in lesser cracking and sunburn incidence. For other attributes, polypropylene pink bagged 30 days after fruit set was found promising. In Litchi under Indian condition, the novel technique of fruit bagging significantly enhance the fruit appearance and quality.
REVIEW | doi:10.20944/preprints202004.0365.v1
Subject: Medicine & Pharmacology, Obstetrics & Gynaecology Keywords: semen quality; male infertility; nutritional model; diet
Online: 20 April 2020 (14:54:04 CEST)
Abnormalities in male fertility constitute about 50% of all infertility causes. According to some data, the quality of human semen has deteriorated by 50-60 % over the last 40 years. A high-fat diet and obesity, the development of which is encouraged by the western lifestyle, affects the structure of spermatozoa, but also the development of the offspring and their health in later stages of life. In obese individuals, disorders on the hypothalamic-pituitary-gonadal axis are observed, as well as elevated oestrogen levels with simultaneous decrease of testosterone, LH and FSH hormone levels. Healthy dietary models clearly correlate with better sperm quality and a smaller risk of abnormalities in parameters, such as sperm count, sperm concentration and motility, as well as lower sperm DNA fragmentation. Apart from mineral components such as zinc and selenium, the role of omega-3 fatty acids and antioxidant vitamins should be emphasized, since their action will be based primarily on the minimization of oxidative stress and inflammation process. Additionally, the incorporation of carnitine supplements and coenzyme Q10 in therapeutic intervention seems also promising. Therefore, it is advisable to have a varied and balanced diet based on vegetables and fruit, fish and seafood, nuts, seeds, whole-grain products, poultry and low-fat dairy products.
ARTICLE | doi:10.20944/preprints202004.0136.v1
Subject: Earth Sciences, Geoinformatics Keywords: groundwater quality; environmental change; Permian Basin; Texas
Online: 9 April 2020 (05:50:27 CEST)
This study evaluates spatial analyses of groundwater quality and environmental changes to obtain information on the groundwater contamination in the Permian Basin, Texas. Coupled with the U.S. government’s open data, these analyses can identify regions where environmental change could have potentially effected groundwater quality. A total of thirty-six wells were selected within the six counties: Andrews, Martin, Ector, Midland, Crane, and Upton. Spatial distribution maps were created for six different parameters: pH, total dissolved solids (TDS), chloride, fluoride, nitrate, and arsenic. Total groundwater quality maps incorporate all the contaminants and denote regions of poor, medium, and optimum conditions. To identify spatial changes in groundwater quality, maps were separated into two different time intervals, 1992-2005 and 2006-2019. We found that groundwater contamination resulted primarily from the mobilization of the contaminant from natural sources or anthropogenic activities such as chemical fertilizers. Overall, groundwater quality decreased during the study period from 1992 to 2019 as population and urban growth began to develop in the Permian Basin. This study contributes on understanding of the response of groundwater quality associated with environmental change in the Permian Basin. Therefore, this research provides important information for groundwater managements in developing plans for the use of water resource in the future for Texas.
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.
ARTICLE | doi:10.20944/preprints201905.0258.v1
Subject: Engineering, Energy & Fuel Technology Keywords: power quality; wind power plant; voltage fluctuations
Online: 21 May 2019 (11:19:57 CEST)
Integration of wind energy into the grid faces a great challenge regarding power quality. The International Electrotechnical Commission (IEC)~61400-21 standard defines the electrical characteristics that need to be assessed in a Wind Turbine (WT), as well as the procedure to measure the disturbances produced by the WT. One of the parameters to be assessed are voltage fluctuations or flicker. To estimate the flicker emission of a Wind Power Plant (WPP), the standard establishes that a quadratic exponent should be used in the summation of the flicker emission of each WT. This exponent was selected based on studies carried out in WPPs with type I and II WTs. Advances in wind turbines technology have reduced their flicker emission, mainly thaks to the implementation of power electronics for the partial or total management of the power injected into the grid. This work is based on measurements from a WPP with 16 type III WTs. The flicker emission of a single WT and of the WPP were calculated. Low flicker emission values at the Point of Common Coupling (PCC) of the WPP were obtained. The flicker estimation at the PCC, based on the measurement from a single WT, was analyzed using different exponents. The results show that a cubic summation performs better than the quadratic one in the estimation of the flicker emission of a WPP with type III WTs.
ARTICLE | doi:10.20944/preprints201901.0254.v2
Online: 17 April 2019 (10:53:57 CEST)
The Safe Drinking Water Act Amendments of 1996 require community water systems in the United States to send consumers Consumer Confidence Reports (CCRs). CCRs contain information on detected contaminants and required educational information about drinking water. The authors of this study developed a survey to evaluate how utilities track consumer feedback, understanding, and the role of the CCR in shaping consumer perceptions about water quality. Responses from this survey indicate it is common for utilities to indirectly track the effectiveness of their CCRs, but few utilities indicated directly evaluating consumer understanding or the effect of CCRs on consumer perceptions.
ARTICLE | doi:10.20944/preprints201904.0002.v1
Subject: Materials Science, Nanotechnology Keywords: nanoparticles; spectral blue shift; amalgam; water quality
Online: 1 April 2019 (08:21:19 CEST)
The emission of mercury (II) from coal combustion and other industrial processes continues to be a concern and have local impact on water resources. The detection of these ions in water with sensitive but rapid testing methods is desirable for environmental screening and fieldwork. Nanoparticles of various chemistries have shown promise for this purpose, as they can be used in simple colorimetric analyses. Silver nanoprisms were chemically synthesized resulting in a blue reagent solution, that transitioned towards yellow and colorless solutions when exposed to Hg2+ ions at various concentrations. A rapid galvanic reduction of Hg2+ onto the nanoprism surfaces is apparently responsible for a change in shape towards spherical nanoparticles, leading to the change in color. There were no interferences by other metal ions in solution, and pH had minimal effect in the range of 6.5 to 9.8. The silver nanoprism reagent provided a detection limit of approximately 0.5 µM (100 µg/L) for mercury (II), which compares favorably with other nanoparticle-based techniques. Further optimization may reduce this detection limit.
ARTICLE | doi:10.20944/preprints201901.0171.v2
Online: 18 February 2019 (09:07:54 CET)
Best Management Practices (BMPs) are commonly used to control pollution in the river basins. Prioritization of BMPs helps improve the efficiency and effectiveness of pollution reduction, especially in Critical Source Areas (CSAs) that produce the highest pollution loads. Recently, the Dez River in Khuzestan, Iran, has become highly eutrophic from the overuse of fertilizers and pesticides. In this basin, dry and irrigated farming produce 77.34% and 6.3% of the Total Nitrogen (TN) load, and 83.56% and 4.3% of the Total Phosphorus (TP) load, respectively. In addition, residential, pasture, and forest land uses together account for 16.36% of the TN and 12.14% of the TP load in this area. The Soil and Water Assessment Tool (SWAT) was implemented to model the Dez River basin and evaluate the applicability of several BMPs, including point source elimination, filter strips, livestock grazing, and river channel management, in reducing the entry of pollution loads to the river. Sensitivity analysis and calibration/validation of the model was performed using the SUFI-2 algorithm in the SWAT Calibration Uncertainties Program (SWAT-CUP). The CSAs were identified using individual (sediment, TN, TP) and combined indices, based on the amount of pollution produced. Among the BMPs implemented, the 10 m filter strip was most effective in reducing TN load (42.61%), and TP load (39.57%).
ARTICLE | doi:10.20944/preprints201901.0225.v1
Subject: Keywords: pathogen, climate change, sand, water quality, modeling
Online: 22 January 2019 (17:28:22 CET)
Humans may be exposed to microbial pathogens at recreational beaches via environmental sources, such as water, sand, and aerosols. Although infectious disease risk from exposure to waterborne pathogens has been an active area of research for decades, sand is a relatively unexplored reservoir of pathogens and fecal indicator bacteria (FIB). Beach sand and water habitats provide unique advantages and challenges to pathogen introduction, growth, and persistence, as well as continuous exchange between habitats. Models of FIB and pathogen fate and transport in sandy beach habitats can help predict the risk of infectious disease from recreational water use, but filling knowledge gaps such as decay rates and potential for microbial growth in beach habitats is necessary for accurate modeling. Climatic variability, whether natural or anthropogenically-induced, adds complexity to predictive modeling, but may increase human exposure to waterborne pathogens via extreme weather events, warming of water bodies and sea level rise in many regions. The popularity of human recreational beach activities, combined with predicted climate change scenarios, could amplify the risk of human exposure to pathogens and related illnesses. Other global change trends such as increased population growth and urbanization are expected to exacerbate contamination events and the predicted impacts of increasing levels of waterborne pathogens on human health. Such changes will alter microbial population dynamics in beach habitats, and will consequently affect the assumptions and relationships used in population models and quantitative microbial risk assessment (QMRA). Here, we discuss the literature on microbial population and transport dynamics in sand-water continuum habitats at beaches, how these dynamics can be modeled, and how climate change and other anthropogenic influences (e.g., land use, urbanization) should be considered when using and developing more holistic, beachshed-based models.
ARTICLE | doi:10.20944/preprints201812.0224.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: self-esteem; quality of sleep; eating; nursing
Online: 18 December 2018 (12:12:23 CET)
In recent decades, organizational research has given special attention to the mechanisms promoting the health and wellbeing of nursing professionals. In this context, self-esteem is a personal resource which influences wellbeing at work and psychological wellbeing of nurses. The purpose of this study was to analyze the mediating role of eating in the effect of sleep quality on self-esteem in nursing professionals. The sample of 1073 nurses were administered the Rosenberg General Self-Esteem Scale, the Pittsburgh Sleep Quality Index and the Three-Factor Eating Questionnaire-R18. The results show that poor sleep quality and type of eating directly and indirectly affect self-esteem. More so, poor sleep quality deteriorated self-esteem through emotional eating, and even though emotional eating facilitated disinhibited eating, this relationship had no significant effects on self-esteem. The findings of this study suggest that hospital management should implement employee health awareness programs on the importance of healthy sleep and design educational interventions for improving the quality of their diet.
ARTICLE | doi:10.20944/preprints201805.0199.v2
Subject: Earth Sciences, Environmental Sciences Keywords: Water Security, Groundwater assessment, Groundwater quality, India
Online: 31 May 2018 (16:47:27 CEST)
Achieving water security and availability for all is among the principle agenda of the UN-Sustainable Development Goals. To achieve the goal of water security, particularly in rapidly expanding cities, identification of safe and sustainable water resources is an absolute necessity. The paper conducts an exploratory investigation in the hydro geochemical characteristics of groundwater and thereby, assess the suitability of groundwater as an alternative and reliable resource for public water supply in the Indian city of Surat. A total of 33-groundwater samples, selected on the basis of aquifer depth, land use signatures, were collected from open, bore, dug wells and hand pumps. After the hydrogeochemical analysis, the study evaluated the present state of the groundwater quality and determined the spatial distribution of groundwater quality parameters such as hardness, electrical conductivity, Cl −, pH, SO42-, and NO3 − concentrations. An interpolation technique, known as ordinary kriging, was used to acquire the spatial distribution of parameters of groundwater quality parameters. Based on the permeability index, result showed that 80% of the sampled groundwater quality falls under excellent class i.e. category I with PI value ranging from 1-24%, whereas the rest 20% of the samples has fallen under good class i.e. category II with PI value ranging from 25 to 75% on the suitability of water for irrigation. The results of this study outlines the unsustainability of groundwater for direct consumption, especially without any improved onsite water treatment, but it is appropriate for the irrigation purposes.
ARTICLE | doi:10.20944/preprints201612.0038.v1
Subject: Chemistry, Analytical Chemistry Keywords: Rosa rugosa; UPLC-DAD; quality control; fingerprint
Online: 7 December 2016 (11:11:00 CET)
A method based on ultra performance liquid chromatography with diode array detector (UPLC-DAD) was developed for quantitative analysis of five active compounds and chemical fingerprint analysis of Rosa rugosa. Ten batches of Rosa rugosa collected from different plantations in the Xinjiang region of China were used to establish the fingerprint. The feasibility and advantages of the used UPLC fingerprint were verified for its similarity evaluation by systematically comparing chromatograms with professional analytical software recommended by State Food and Drug Administration (SFDA) of China. In quantitative analysis, the five compounds showed good regression (R2=0.999 5) within the test ranges and the recovery of the method was in the range of 94.2–103.8%. The similarities of the fingerprints of 10 batches of the samples were more than 0.981. The developed UPLC fingerprint method is simple, reliable and validated for the quality control and identification of Rosa rugosa. Additionally, simultaneous quantification of five major bioactive ingredients in the Rosa rugosa samples was conducted to interpret the consistency of the quality test. The results indicated that the UPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantification analysis, can be successfully used to assess the quality and to identify the authenticity of Rosa rugosa.
CASE REPORT | doi:10.20944/preprints201608.0174.v1
Online: 18 August 2016 (10:36:09 CEST)
The ambient air quality data for particulate matter as well as criteria of gaseous pollutants were assembled during December 2013 to December 2015 from the Continuous Air Quality Monitoring Station (CAMS) located at Agrabad, Chittagong. The observation showed that during April- October, 24 hour average concentration of PM10 and PM2.5 were within the National Ambient Air Quality Standard (NAAQS) level but it increased occasionally by more than two and a half times during the whole non-monsoon period (November-March). The highest values found of PM2.5 were 321.1 µg/m3 in January, 2013 and 220.34 µg/m3 in December 2015. Whether, the highest alarming concentration of PM10 was reported as 474 µg/m3 in January 2007. The other gaseous pollutants such as SO2, NO2, O3, CO and Hydrocarbons remain well within the permissible limit except dry non-monsoon period. The yearly average increase of Air Quality Index (AQI) value indicates the growth rate of air pollution in Chittagong city. The main responsible pollutant for air pollution is found PM2.5.
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
ARTICLE | doi:10.20944/preprints202109.0344.v1
Subject: Earth Sciences, Environmental Sciences Keywords: lower Athabasca River; Oil Sands Region; quasi-2D modelling; Water-Quality Analysis Simulation Program (WASP); water-quality modelling
Online: 20 September 2021 (16:07:09 CEST)
A quasi-two-dimensional (quasi-2D) modelling approach is introduced to mimic transverse mixing of an inflow into a river from one of its banks, either an industrial outfall or a tributary. The concentrations of determinands in the inflow vary greatly from those in the river, leading to very long mixing lengths in the river downstream of the inflow location. Ideally, a two-dimensional (2D) model would be used on a small scale to capture the mixing of the two flow streams. However, for large-scale applications of several hundreds of kilometres of river length, such an approach demands too many computational resources and too much computational time, especially if the application will at some point require ensemble input from climate-change scenario data. However, a one-dimensional (1D) model with variables varying in the longitudinal flow direction but averaged across the cross-sections is too simple of an approach to capture the lateral mixing between different flow streams within the river. Hence, a quasi-2D method is proposed in which a simplified 1D solver is still applied but the discretisation of the model setup can be carried out in such a way as to enable a 2D representation of the model domain. The quasi-2D model setup also allows secondary channels and side lakes in floodplains to be incorporated into the discretisation. To show proof-of-concept, the approach has been tested on a stretch of the lower Athabasca River in Canada flowing through the oil sands region between Fort McMurray and Fort MacKay. A dye tracer and suspended sediments are the constituents modelled in this test case.
ARTICLE | doi:10.20944/preprints201911.0114.v1
Subject: Earth Sciences, Atmospheric Science Keywords: air quality; mobile observations; light rail; particulate matter; ozone; health outcomes; urban pollution; wildfires; air quality policy; environmental justice
Online: 10 November 2019 (14:36:21 CET)
Observing air quality from sensors onboard light rail cars in Salt Lake County, Utah began as a pilot study in 2014 and has now evolved into a five-year state-funded program. This metropolitan region suffers from both elevated ozone levels during summer and high PM2.5 events during winter. Pollution episodes result predominantly from local anthropogenic emissions but are also impacted by regional transport of dust, chemical precursors to ozone, and wildfire smoke as well as being exacerbated by the topographical features surrounding the city. Two electric light-rail train cars from the Utah Transit Authority light-rail Transit Express (“TRAX”) system were outfitted with PM2.5 and ozone sensors to measure air quality at high spatial and temporal resolution in this region. Pollutant concentration data underwent quality control procedures to determine whether the train motion affected the readings and how the sensors compared against regulatory sensors. Quality assurance results from data obtained over the past year show that TRAX Observation Project sensors are reliable, which corroborates earlier preliminary validation work. Two case studies from summer 2019 are presented to illustrate the strength of the finely-resolved air quality observations: 1) an elevated ozone event and 2) elevated particulate pollution resulting from 4th of July fireworks. The mobile observations were able to capture spatial gradients as well as pollutant hotspots during both of these episodes. Sensors have been recently added to a third light rail train car, which travels on a north-south oriented rail line along which we were unable to monitor air quality previously. The TRAX Observation Project is currently being used to provide reliable pollutant data for health studies and inform urban planning efforts. Links to real-time data displays and updated information on the quality-controlled data from this study are available at https://atmos.utah.edu/air_quality/trax/.
ARTICLE | doi:10.20944/preprints202205.0204.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: microgrid; DNN; parallel inverters; island mode; power quality
Online: 16 May 2022 (10:13:15 CEST)
The microgrid is a small-scale, autonomous decentralized power plant with its own distributed generation, storage capacity and multiple loads, with the capacity to function in grid interconnected and an island mode. The decentralized control of microgrids with parallel operated voltage source converters (VSCs) is proposed in this paper to improve power quality using a machine learning approach. The DNN based MPPT controller is proposed and its best performance is presented. The SRF-PLL is utilized for AC side synchronization in VSC control. The proposed microgrid involves two PV arrays fed to two voltage source converters along with their independent controls, connected in parallel through LC filters and line coupling transformers and serves the loads at PCC. The proposed model is simulated using MATLAB/Simulink. The dq-framed inner loop control is employed to individually regulate the real and reactive power at the point of common coupling. Furthermore, the proposed model is analyzed and compared by employing a mathematical model of AC system dynamics, inner loop control, output voltage quality, AC harmonic spectrum analysis, and total harmonic distortion (THD) in both grid interconnected and island mode. In island mode, AC harmonic spectrum and THD are accomplished within the permissible range.
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/preprints202201.0264.v1
Subject: Medicine & Pharmacology, Pediatrics Keywords: pediatric pneumonia; hospital readmission; healthcare quality; hospital costs
Online: 18 January 2022 (16:08:11 CET)
Pneumonia is the leading cause of hospitalization in pediatric patients. Disease severity greatly influences pneumonia progression and adverse health outcomes such as hospital readmission. Hospital readmissions have become a measure of healthcare quality to reduce excess expenditures. The aim of this study was to examine 30-day all-cause readmission rates and evaluate the association between pneumonia severity and readmission among pediatric pneumonia hospitalizations. Using 2018 Nationwide Readmissions Database (NRD), we conducted a cross-sectional study of pediatric hospitalizations for pneumonia. Pneumonia severity was defined by the presence of respiratory failure, sepsis, mechanical ventilation, dependence on long-term supplemental oxygen, and/or respiratory intubation. Outcomes of interest were 30-day all-cause readmission, length of stay, and cost. The rate of 30-day readmission for the total sample was 5.9%, 4.7% for non-severe pneumonia, and 8.7% for severe pneumonia (p<0.01). Among those who were readmitted, hospitalizations for severe pneumonia had a longer length of stay (6.5 vs. 5.4 days, p<0.01) and higher daily cost ($3,246 vs. $2,679, p<0.01) than admissions for non-severe pneumonia. Factors associated with 30-day readmission were pneumonia severity, immunosuppressive conditions, length of stay, and hospital case volume. To reduce potentially preventable readmissions, clinical interventions to improve the disease course and hospital system interventions are necessary.
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.
ARTICLE | doi:10.20944/preprints202109.0079.v1
Subject: Earth Sciences, Geology Keywords: Groundwater quality; Shallow aquifers; agronomics; geospatial techniques; Aligarh
Online: 6 September 2021 (07:57:47 CEST)
Monitoring of groundwater quality in today's scenario is very much important. Due to urbanization and population pressure regular monitoring of groundwater for drinking as well as irrigation purposes need a major concern. With this aim, a study has been carried out consisting 26 groundwater samples in May 2017, to access the physiochemical characteristic, water quality index (WQI) of groundwater by using GIS software and to find out the groundwater suitableness for drinking as well as for irrigation purpose. The pH is slightly alkaline and the TDS is much more than prescribed limits of BIS. The trend of cations in groundwater are Ca2+>Na+>Mg2+>K+ while anions trend is HCO3->SO42->Cl->NO3->CO32->F-. The Ca-Mg-HCO3 and Na-K-Cl-SO4 types of groundwater facies were dominant. Generally, the chemical changes in groundwater are administered by the evaporation process with ion exchange, and mixing of particles is the significant source of the solute acquisition process. WQI of the study area suggested that the 15% sample is unsuitable, 69% is poor and remaining is good for drinking uses. The potential salinity of the groundwater sample is nearly high although the majority of the sample is suited for irrigation activities.
ARTICLE | doi:10.20944/preprints202106.0711.v1
Subject: Social Sciences, Accounting Keywords: Quality of economic growth; environmental regulation; technological innovation
Online: 29 June 2021 (14:14:33 CEST)
Abstract：This paper uses the balanced panel data from 29 provinces (autonomous regions and municipalities) in China for a total of 17 years from 2000 to 2016 as a research sample, and establishes an empirical model to examine the impact of environmental regulations and technological innovation on the quality of economic growth. Then this paper test technological innovation as a threshold variable, in which play a regulatory role. Taking the provincial balanced panel data as a research sample, a fixed effect model, a system GMM model, and a panel threshold model were established for empirical testing and the robustness test. Based on the empirical results, this article draws the following conclusions: from a national perspective, environmental regulations and technological innovation can significantly promote the quality of economic growth; from a regional perspective, there are regional differences in impact effects. Under the constraints of environmental regulations, the promotion effect of technological innovation on the quality of economic growth will be reduced; the impact of environmental regulation on the quality of economic growth will have a "threshold effect", and environmental regulation can significantly promote the quality of economic growth only after crossing the threshold and the threshold of technological innovation.
ARTICLE | doi:10.20944/preprints202106.0604.v1
Subject: Engineering, Civil Engineering Keywords: ventilation; indoor air quality; COVID-19; aerosols; Spain
Online: 24 June 2021 (12:02:57 CEST)
After the arrival of a new airborne virus to the world, science is aiming to develop solutions to withstand the spread and contagion of the SARS-CoV-2 coronavirus. The most severe among the adopted measures is to remain in home isolation for a significant number of hours per day, in order to avoid the spreading of the infection in an uncontrolled way through public spaces. Recent literature showed that the major route of transmission is via aerosols produced especially in poorly ventilated inner spaces. With regard to contagion rates, accumulated incidence or number of hospitalizations due to COVID-19, Spain has reached very high levels, therefore this article develops a quantitative and qualitative analysis of the requirements established in Spain with respect to the European framework in reference to ventilation parameters indoors. For this, a case study has been analyzed, representing a common residence in current Spanish residential developments. Results show that the criteria established in the applicable regulations are not sufficient to ensure health as well as to avoid contagion by aerosols indoors.
ARTICLE | doi:10.20944/preprints202103.0323.v1
Subject: Medicine & Pharmacology, Allergology Keywords: cardiorespiratory fitness; VO2 peak; sleep quality, physical activity
Online: 11 March 2021 (16:04:34 CET)
Abstract: Background: Recently, cardiorespiratory fitness (CRF) has been postulated as an adverse health outcome related to poor sleep quality. However, studies investigating the relationship between CRF with subjective sleep quality index are scarce. Thus, the current study aimed to investigate the association between CRF and Pittsburgh sleep quality index (PSQI) in apparently healthy people. The secondary aim was to investigate the association between reported physical activities (PA) and PSQI. Methods: 33 apparently healthy male participants volunteered to participate. CRF (VO2 peak) was measured via cardiopulmonary exercise testing on a treadmill. A short form of the International physical activity questionnaire (IPAQ) was used to measure PA, and PSQI was used for sleep quality index. Results: There was no correlation between CRF and PSQI total score or any component of the PSQI. Also, there was no correlation between IPAQ and PSQI total score. Categorical data analysis of the two questionnaires revealed that 45.5% of the participants reported low physical activity and poor sleep quality. Conclusions: There was no association between CRF, reported PA with subjective sleep quality index. The use of objective tools for assessing the quality and quantity of sleep should be recommended for future studies as it may clarify the association between CRF and sleep quality.
ARTICLE | doi:10.20944/preprints202101.0543.v1
Subject: Biology, Anatomy & Morphology Keywords: Blueberry; Pre-breeding; hybridization; V. elliottii; Fruit quality
Online: 26 January 2021 (15:55:14 CET)
Wild germplasm can be classified as the raw material essential for crop improvement. Introgression of wild germplasm is normally used in breeding to increase crop quality or resilience to evolving biotic and abiotic threats. Here, we explore the potential of introgressing Vaccinium elliottii into commercial blueberry germplasm. Vaccinium elliottii is a wild diploid blueberry species endemic to the southeastern United States that possesses highly desirable and economically important traits for blueberry breeding such as: short bloom to ripe period, adaptation to upland sandy soils, disease resistance, firmness, and pleasant flavor. To examine the potential of hybridization, we evaluated populations of interspecific hybrids across multiples stages of breeding (i.e., F1, F2, and backcrosses) in two crop seasons. We used our extensive pedigree data to generate breeding values for pre-breeding blueberry hybrid populations. Hybrid performance was evaluated considering fitness (i.e., plant vigor and plant height) in addition to evaluating six fruit-quality and marketable-related traits (i.e., size, firmness, acidity, soluble solids, weight, and yield). Overall, F2 and backcrosses rapidly achieved market thresholds, presenting values not significantly different from commercial blueberry germplasm. Our results confirmed the potential of exploiting the high genetic variability contained in V. elliotii for interspecific hybridization. Additionally, we developed germplasm resources that can be further evaluated and utilized in the breeding process, advancing selections for fruit quality and environmental adaptation.
ARTICLE | doi:10.20944/preprints202101.0464.v1
Subject: Engineering, Automotive Engineering Keywords: Water quality; dissolved oxygen; Neural network; Metaheuristic schemes
Online: 25 January 2021 (09:50:43 CET)
The great importance of estimating dissolved oxygen (DO) dictates utilizing proper evaluative models. In this work, a multi-layer perceptron (MLP) network is trained by three capable metaheuristic algorithms, namely multi-verse optimizer (MVO), black hole algorithm (BHA), and shuffled complex evolution (SCE) for predicting the DO using the data of the Klamath River Station, Oregon, US. The records (DO, water temperature, pH, and specific conductance) belonging to the water years 2015 - 2018 (USGS) are used for pattern analysis. The results of this process showed that all three hybrid models could properly infer the DO behavior. However, the BHA and SCE accomplished this task by simpler configurations. Next, the generalization ability of the developed patterns is tested using the data of the 2019 water year. Referring to the calculated mean absolute errors of 1.0161, 1.1997, and 1.0122, as well as Pearson correlation coefficients of 0.8741, 0.8453, and 0.8775, the MLPs trained by the MVO and SCE perform better than the BHA. Therefore, these two hybrids (i.e., the MLP-MVO and MLP-SCE) can be satisfactorily used for future applications.
REVIEW | doi:10.20944/preprints202101.0275.v1
Subject: Life Sciences, Biochemistry Keywords: Vicia faba; legume improvement; quality traits; disease resistance
Online: 14 January 2021 (14:18:29 CET)
Faba bean (Vicia faba L.) was considered a minor crop in the Canadian prairies until recently, but its potential for cultivation is increasing due to its positive environmental impact and economic value. This review provides a historical summary of faba bean improvement in western Canada. Although traditional breeding methods have proved useful, in the last decade faba bean improvement has benefited from advances in genetics, biochemistry and molecular breeding tools. The overall breeding goal is to develop high yielding germplasm with improved agronomic characteristics that will be of economic value to the emerging faba bean sectors, including the plant protein industry. To maximize value and acceptance by producers, processors and the food industry as a source of protein and dietary fibre, future faba bean varieties need to be high-yielding, have diverse seed size classes, disease resistance, genetically low vicine-convicine concentration, and have wider adaptation to different agro-ecological zones of Canada. The experiences over the last 40 years of faba bean improvement in western Canada may be useful to other breeding programs globally located in regions with similar agroecology. In the past 10–15 years, faba bean genetic development in Canada has benefited greatly from research and development interactions with most of the faba bean research programs in northern Europe.
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.
Subject: Life Sciences, Biotechnology Keywords: Data Quality; Sequence reporting standards; RaTG13 Sequence; De-novo assembly
Online: 26 July 2021 (12:08:30 CEST)
The origin of SARS-CoV-2 is debated, even after 18 months into the COVID-19 pandemic and a special investigation conducted by the World Health Organization. The RaTG13 sequence has been a highlight of discussions surrounding the origin of SARS-CoV-2. Here we express our opinion about the need for better reporting standards for information about sequencing data, especially for pathogens, citing our findings with the reported RaTG13 genome.
ARTICLE | doi:10.20944/preprints202007.0051.v2
Subject: Social Sciences, Library & Information Science Keywords: COVID-19; WHO; database; systematic review; data quality
Online: 2 August 2020 (17:43:38 CEST)
Introduction: A large number of COVID-19 publications has created a need to collect all research-related material in practical and reliable centralized databases. The aim of this study was to evaluate the functionality and quality of the compiled World Health Organisation COVID-19 database and compare it to Pubmed and Scopus. Methods: Article metadata for COVID-19 articles and articles on 8 specific topics related to COVID-19 was exported from the WHO global research database, Scopus and Pubmed. The analysis was conducted in R to investigate the number and overlapping of the articles between the databases and the missingness of values in the metadata. Results: The WHO database contains the largest number of COVID-19 related articles overall but retrieved the same number of articles on 8 specific topics as Scopus and Pubmed. Despite having the smallest number of exclusive articles overall, the highest number of exclusive articles on specific COVID-19 related topics was retrieved from the Scopus database. Further investigation revealed that PubMed and Scopus have more comprehensive structure than the WHO database, and less missing values in the categories searched by the information retrieval systems. Discussion: This study suggests that the WHO COVID-19 database, even though it is compiled from multiple databases, has a very simple and limited structure, and significant problems with data quality. As a consequence, relying on this database as a source of articles for systematic reviews or bibliometric analyses is undesirable.
ARTICLE | doi:10.20944/preprints202007.0537.v1
Online: 23 July 2020 (08:10:38 CEST)
Energy use is of crucial importance for the global challenge of climate change but also an essential part of daily life. Hence, research on energy needs to be robust and valid. Other scientific disciplines have experienced a reproducibility crisis, that is, existing findings could not be reproduced in new studies, and energy research might be impacted as well. In this paper, we suggest the ‘TReQ’ approach to improve the research practices in the energy field and arrive at greater Transparency, Reproducibility, and Quality. We acknowledge the specific challenges of energy research and suggest a highly adaptable suite of tools that can be applied to research approaches across this multi-disciplinary and fast-changing field. In particular, we introduce preregistration of studies, making data and code publicly available, using preprints, and employing reporting guidelines to heighten the standard of research practices within the energy field. We argue that through wider adoption of these tools, we will be able to have greater trust in the findings of research used to inform evidence-based policy and practice in the energy field.
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.
Subject: Social Sciences, Economics Keywords: bidding rank; information asymmetry; search engine; product quality
Online: 20 April 2020 (14:50:57 CEST)
This article investigates the information matching efficiency of the sponsored auction mechanism of search engine platform by implementing consumer purchase strategy. Then we examine the incentive mechanism for sellers to report product quality truthfully under information asymmetry and the reason how product quality signal could improve information matching efficiency of the sponsored auction mechanism. Using the data collected from Baidu search engine, we empirically test the theoretical research results. Our main research finding: under information asymmetry and without product quality signal mechanism, the equilibrium of bidding rank cannot match the consumer purchase strategy at all, causing the consumer welfare to suffer double losses due to the adverse selection of sellers. In the contrast, the search engine could improve partially the information matching efficiency of the sponsored search auction mechanism by identifying the product quality signal brought by the sellers with the highest product quality. However, the search engine has no incentive to design product quality signal for sellers.