ARTICLE | doi:10.20944/preprints202205.0331.v1
Subject: Social Sciences, Psychology Keywords: Robot-based activities; hospitalized children; psychological health; well-being; CoderBot; positive emotion; single-setting
Online: 24 May 2022 (10:16:05 CEST)
Being hospitalized is a threatening and stressful experience for many children. From a psychological point of view, children may experience increased feelings of anxiety and fear that can negatively interfere with behavioral, cognitive, and emotional outcomes. To limit these impacts on children's well-being and mental health, interventions that could contribute to protecting the emotional domain of hospitalized children are welcomed. The present research reported a single-setting case study intervention to evaluate the impact of educational play-based activity with a CoderBot robot in a pediatric short-term recovery ward (N=61). The methodology included multiple sources of data (i.e., children, parents, nurses), observations on the field, and a sequential (quantitative-qualitative) mixed-method approach to data analysis. Results supported the idea that robot-based activities were associated with increased participant well-being (particularly positive emotions). The conclusions of this pilot study discuss the strengths, limitations, and further developments of using robots with hospitalized children.
ARTICLE | doi:10.20944/preprints201804.0327.v2
Subject: Engineering, Electrical And Electronic Engineering Keywords: Overcurrent Relay (OCR); Genetic Algorithm (GA); Time Dial Setting (TDS); Plug Setting Multiplier (PSM); Optimal OCR setting and coordination and DigSILENT power factory
Online: 27 April 2018 (15:49:58 CEST)
This paper presents a study on optimization of Overcurrent relay (OCR) coordination protection scheme for Sustainable Standalone Hydrokinetic Renewable Energy (SHRE) distribution network at Batang Rajang river, located at Kapit Sarawak, Malaysia by turning river stream into power generation source. The purpose of the project is to develop rural electrification system for native long houses along the river. The research study is tested on a DigSILENT develop model of the SHRE distribution network and in accordance with all respectively unique parameters and relevant standards. Since this is a new standalone distribution system, an efficient and properly coordinated overcurrent protection system must be provided. Improper and miscoordination among OCRs result in maloperation of the protection system that can lead to false tripping and an unnecessary outage and power system instability. Thus, the objective of this work is to employ Genetic Algorithm (GA) technique in Matlab/Simulink for optimal overcurrent coordination and settings among all OCRs in the proposed distribution network in order to improve the speed of OCR tripping operation. The GA is used because the project is fast track and requiring the simplest method available. In this strategy, time dial setting (TDS) is optimized by using plug setting multiplier (PSM) as the constraint. The obtained results show a significant improvement of the relay operating time of 36.01% faster than that of conventional numerical technique during fault occurrence. Thus, an efficient and reliable overcurrent protection scheme has been achieved for the SHRE distribution network.
CASE REPORT | doi:10.20944/preprints202308.1607.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: tuberculosis; disseminated TB; low-income setting
Online: 23 August 2023 (09:15:57 CEST)
Disseminated or military tuberculosis (TB) is defined as the presence of at least two non-contiguous sites of Mycobacterium tuberculosis, occurring as a result of progressive primary infection, reactivation and spread of a latent focus or due to iatrogenic origin. Disseminated TB represents a life-threatening condition, especially in at-risk children and when the diagnosis and treatment are delayed. We report on a case of a 3-year old boy who presented with long-lasting unrecognised disseminated TB that was successfully managed in a low-resource setting.
ARTICLE | doi:10.20944/preprints202309.0054.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: nature-based solutions; habitat types; urban planning; approach setting
Online: 1 September 2023 (10:18:33 CEST)
The study focuses on solving urban challenges such as temperature reduction, urban stormwater management, noise reduction, air quality improvement, and CO2 concentrations reduction, and suggests terrestrial and freshwater habitat types (HTs) found in Europe, as innovative forms of nature-based solutions (NBS) for them. Establishment of native HTs in different urban environments to solve urban challenges would enhance biodiversity at different levels and integrate this aspect in urban planning. This contribution builds on the recognition that surfaces of vegetated terrain are the most versatile NBS in addressing the broadest range of environmental problems in urban areas and that the processes running within these green spaces offer the key to socio-ecological improvements of such areas. Employing narrative literature review, qualitative content analysis, and interdisciplinary expert discussion this paper defines why and how native HTs of unchanged nature can be implemented as NBS in the urban environment, indicate potential HTs for specific urban challenges and presents an approach to the inclusion of HTs as NBS into spatial planning documents at national, regional, and local levels. The proposed planning approach attributes added value to HT, and by linking the concepts of NBS and HT integrates them into urban planning.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: single particle tracking; single molecule biophysics; fluorescence
Online: 25 January 2021 (12:26:31 CET)
Single particle tracking (SPT) is a powerful class of methods for studying the dynamics of biomolecules inside living cells. The techniques reveal the trajectories of individual particles, with a resolution well below the diffraction limit of light, and from them the parameters defining the motion model, such as diffusion coefficients and confinement lengths. Most existing algorithms assume these parameters are constant throughout an experiment. However, it has been demonstrated that they often vary with time as the tracked particles move through different regions in the cell or as conditions inside the cell change in response to stimuli. In this work, we propose an estimation algorithm to determine time-varying parameters of systems that discretely switch between different linear models of motion with Gaussian noise statistics, covering dynamics such as diffusion, directed motion, and Ornstein-Uhlenbeck dynamics. Our algorithm consists of three stages. In the first stage, we use a sliding window approach, combined with Expectation Maximization (EM) to determine maximum likelihood estimates of the parameters as a function of time. These results are only used to roughly estimate the number of model switches that occur in the data to guide the selection of algorithm parameters in the second stage. In the second stage, we use change detection (CD) techniques to identify where the models switch, taking advantage of the off-line nature of the analysis of SPT data to create non-causal algorithms with better precision than a purely causal approach. Finally, we apply EM to each set of data between the change points to determine final parameter estimates. We demonstrate our approach using experimental data generated in the lab under controlled conditions.
REVIEW | doi:10.20944/preprints202308.0083.v1
Subject: Engineering, Bioengineering Keywords: single-cell analysis; electrical manipulation; single-cell application
Online: 1 August 2023 (10:50:09 CEST)
Biological parameters extracted from electrical signals from various body parts have been used for many years to analyze the human body and its behavior. In addition, electrical signals from cancer cell lines, normal cells, and viruses, among others, have been widely used for the detection of various diseases. Single-cell parameters such as cell and cytoplasmic conductivity, relaxation frequency, and membrane capacitance are important. There are many techniques available to characterize biomaterials, such as scanning tunneling microscopy (STM), nanotechnology, microstrip cavity resonance measurement, dielectric impedance measurement (DEPIM), etc. This article reviews the single cell isolation and sorting techniques, summarizes the common single cell operations such as impedance flow cytometry, cell electrical impedance, electrical impedance sensing, and summarizes the current single cell analysis techniques and their applications.
REVIEW | doi:10.20944/preprints202307.1083.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: Neuropsychology; Anxiety Disorders; Clinical Setting; Generalized Disorder; Prisma; Systematic Review
Online: 17 July 2023 (11:11:51 CEST)
The purpose of this systematic review is to examine the various articles published in the field of neuropsychology of anxiety research in terms of publication type and volume, methodology, and subject matter. The significance of this topic derives from the clinical and functional consequences of cognitive symptoms. Generalized anxiety disorder refers to the cluster of clinical symptoms characterized by predominant anxious anticipation and difficulty controlling worry. In order for the review to be systematic and reproducible, a search of the PsycINFO, Scopus, PubMed, Elsevier databases and an analysis using the PRISMA method are suggested. After analyzing the research data, empirical studies evaluating the clinical neuropsychology of generalized anxiety disorder are discussed.
ARTICLE | doi:10.20944/preprints202201.0416.v1
Subject: Biology And Life Sciences, Virology Keywords: Goal setting; goal adjustment; lockdown; qualitative survey; reflexive thematic analysis
Online: 27 January 2022 (11:27:26 CET)
Since the end of 2019 and throughout 2020 the world has been devastated by the SARS COVID-19 pandemic. The sport world suddenly had to deal with a massive reorganization of events with important implications on the physical and psychological preparation of athletes and coaches. The purpose of this study was to explore how these changes impacted coaches’ and athletes’ goal setting strategies and their experience of goal adjustment. As part of a wider mixed-method project involving 2162 coaches and 1354 athletes, an online qualitative survey was used, and data collected were analyzed using reflexive thematic analysis. Findings highlighted three overarching themes, in response to goal adjustment: “Moving on toward new goals”, “Letting go of goals”, and “Trying to hold on”, with several themes and sub-themes identifying different nuances of athletes’ and coaches’ experience. The implications of such findings for the mental preparation of high-level athletes are discussed in two ways. Firstly, in light of existing literature on goal setting from an applied perspective; secondly, in the broader perspective of the sport culture and the application of our themes to other challenging moments that sport professionals might encounter.
Subject: Public Health And Healthcare, Nursing Keywords: barcode medication administration (BCMA); nurses’ workflow; inpatient setting; drug round
Online: 28 July 2020 (05:07:23 CEST)
Barcode medication administration (BCMA) is advocated as a technology that reduces medication errors relating to incorrect patient identity, drug or dose. Little is known, however, about the impact it has on nursing workflow. Our aim was to investigate the impact of BCMA on nursing activity and workflow. A comparative study was conducted on two similar surgical wards within an acute UK hospital. We observed nurses during drug rounds on a non-BCMA ward and a BCMA ward. Data were collected on drug round duration, timeliness of medication administration, patient identification, medication verification and general workflow patterns. BCMA appears not to alter drug round duration, although it may reduce the administration time per dose. Workflow was streamlined, with a reduction in use of the medicines room. The rate of patient identification increased from 74% (of 47) patients to 100% (of 43), with 95% of 255 scannable medication doses verified using the system. This study suggests that BCMA does not affect drug round duration; further research is required to determine the impact it has on timeliness of medication administration. There was reduced variability in the medication administration workflow of nurses, along with an increased patient identification rate and high medication scan rate, representing potential benefits to patient safety.
ARTICLE | doi:10.20944/preprints202307.0720.v1
Subject: Engineering, Civil Engineering Keywords: fast-setting concrete; repair of concrete pavement; development of compressive strength
Online: 12 July 2023 (02:30:29 CEST)
On the analyzed section of 2.4 km of the national road No. 50 of the Młodzieszyn bypass, it was carried out by a consortium of OAT and SAT companies in the period April-September 2019, under constant traffic in the field of repairing the concrete pavement by replacing slabs, levelling them and sealing expansion joints, roughening and roadside reinforcements.
ARTICLE | doi:10.20944/preprints202105.0031.v1
Subject: Computer Science And Mathematics, Applied Mathematics Keywords: finance; portfolio optimization; tail eigenvalue amplification; high-dimensional setting; factor models
Online: 5 May 2021 (10:40:08 CEST)
In this paper we provide a highly selected review and synthesis on some of the recent and notable contribution to research in portfolio analysis. A unique perspective on this development in the literature is offered in this paper by judiciously identifying a few sample eigenvalues adjustment patterns in a portfolio that leads to an improvement in the out-of-sample portfolio Sharpe ratio when the population covariance matrix admits a high-dimensional factor model. These patterns unveil a key insight into a portfolio performance improvement and shed an important light on the effectiveness of a few recently introduced ”robust to estimation errors” covariance matrix estimation approaches, which were not originally designed with the goal to improve the out-of-sample portfolio performance.
REVIEW | doi:10.20944/preprints202306.0983.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: tripodal ligands; lanthanides; single-molecule magnets; single-ion magnets; axiality
Online: 14 June 2023 (04:47:53 CEST)
The main property of tripodal ligands is the predictable type of coordination. Homo- and heteroleptic lanthanide complexes with tripodal ligands are a representative class of compounds. However, despite the fact that many of them are paramagnetic their magnetic behavior is poorly understood. This is because their photophysical and catalytic properties have been more attractive. In the present review, we are trying to summarize the available structural information and extremely few data on magnetic properties in order to draw some conclusions about the prospective of tripods using in the design of quantum molecular magnets based on Ln ions. We would like to draw the reader's attention to the fact that despite the consideration of a large part of the currently known lanthanide compounds with tripodal ligands, this review is not exhaustive. However, our goal was to draw the attention of researchers to the fact that a whole niche of air-stable Ln complexes remained outside the attention of magnetochemists and theoreticians.
ARTICLE | doi:10.20944/preprints202303.0103.v1
Subject: Computer Science And Mathematics, Applied Mathematics Keywords: single machine; single breakdown; schedule; flowtime; stochastic optimization; online optimization
Online: 6 March 2023 (13:00:04 CET)
We consider the problem of scheduling tasks on a single machine subject to an uncertain breakdown to minimize the flowtime. Assume the machine is unavailable during the breakdown; the starting time of the breakdown is a random variable s with distribution function D(s) and the terminating time of the breakdown has no any other information; jobs are non-resumable. Under the assumptions, starting from the perspective of statistical optimization, we first define the expected competitive ratio of an algorithm to find the optimized solution with the considered problem. Further, we propose and prove a certain result on the expected competitive ratio of the SPT rule. In particular, we show that under a quite loose condition the expected competitive ratio of the SPT rule is no more than 5/4. Meanwhile, we also make some discussions about our studies. What we have done will rich and improve the studying results on the area of scheduling to minimize flowtime and advance the development of online optimization and statistical optimization.
ARTICLE | doi:10.20944/preprints202109.0504.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: single cell RNAseq; single cell ATACseq; sparsely connected autoencoder; pseudo-bulk
Online: 29 September 2021 (17:26:18 CEST)
Background: Biological processes are based on complex networks of cells and molecules. Single cell multi-OMICs is a new tool aiming to provide new incites in the complex network of events controlling the functionality of the cell.; Methods: Since single cell technologies provide many sample measurements, they are the ideal environment for the application of deep learning and machine learning approaches. An autoencoder (AE) is composed of an encoder and a decoder sub-model. AE are very powerful in data compression and noise removal. However, the decoder model remains a black box from which is impossible to depict the contribution of the single input elements. We have recently developed a new class of autoencoders, called Sparsely Connected Autoencoders (SCA), which have the advantage of providing a controlled association among the input layer and the decoder module. This new architecture has the benefit that the decoder model is no anymore a black box and it can be used to depict new biologically interesting features from single cell data; Results: In this paper, we show that SCA hidden layer can grab new information usually hidden in single cell data, like as providing clustering on meta-features difficult, i.e. transcription factors expression, or impossible, miRNA expression, to depict in single cell RNAseq data. Furthermore, a SCA representation of cell clusters has the advantage of simulating a conventional bulk RNAseq, which is a data transformation allowing the identification of similarity among independent experiments; Conclusions: In our opinion, SCA represent the bioinformatics version of a “Swiss Army knife” for the extraction of hidden knowledgeable features from single cell OMICs data.
Subject: Social Sciences, Transportation Keywords: Optimal bus dispatching system; Modular bus units; Frequency setting problem; 3D-MFD
Online: 28 June 2020 (20:13:46 CEST)
This study proposes a novel flexible bus dispatching system where a fleet of fully automated modular bus units, together with conventional buses, serves the passenger demand. These modular bus units can either operate individually or combined (forming larger modular buses with a higher passenger capacity). This provides enormous flexibility to manage the service frequencies and vehicle allocation, reducing thereby the operating cost and improving passenger mobility. We develop an optimization model used to determine the optimal composition of bus units and the optimal service frequency at which the buses (both conventional and modular) are dispatched across each bus line. We explicitly account for the dynamics of traffic congestion and complex interactions between the modes at the network level based on the recently proposed three-dimensional macroscopic fundamental diagram (3D-MFD). To the best of our knowledge, this is the first application of the 3D-MFD and modular bus units for the frequency setting problem in the domain of bus operations. Numerical results show the improvements in the total system cost made by adapting the number of combined modular bus units and their dispatched frequencies to the evolution of both, the car and the passenger demand. A comparison with the commonly used approach that considers only the bus system (neglecting the complex multimodal interactions and congestion propagation) reveals the value of the proposed modeling framework.
ARTICLE | doi:10.20944/preprints201810.0526.v2
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: calcium carbonate cement; setting reaction; (re)crystallization kinetics; cement strengthening; crystal bridging
Online: 6 May 2020 (14:50:13 CEST)
Calcium carbonate cements have been synthesized by mixing amorphous calcium carbonate and vaterite powders with water to form a cement paste and study how mechanical strength is created during the setting reaction. In-situ XRD was used to monitor the transformation of ACC and vaterite phases into calcite and a rotational rheometer was used to monitor the strength evolution. There are two characteristic time scales of the strengthening of the cement paste. The short timescale of the order 1 hour is controlled by smoothening of the vaterite grains, allowing closer and therefore adhesive contacts between the grains. The long timescale of the order 10-50 hours is controlled by the phase transformation of vaterite into calcite. This transformation is, unlike in previous studies using stirred reactors, found to be mainly controlled by diffusion in the liquid phase. The evolution of shear strength with solid volume fraction is best explained by a fractal model of the paste structure.
REVIEW | doi:10.20944/preprints202003.0200.v1
Subject: Public Health And Healthcare, Nursing Keywords: critical care nurses; critical care setting; experiences; patient advocacy; systematic review; understanding
Online: 12 March 2020 (04:42:24 CET)
Objectives: The purpose of this systematic review was to ascertain critical care nurses’ understanding and experiences of patient advocacy in adult critical care settings. The specific objectives were to identify how critical care nurses define patient advocacy, to explore the understanding and experiences of critical care nurses regarding patient advocacy, to explore critical care nurses’ role in patient advocacy, and to ascertain the barriers to encouraging advocacy in the critical care setting. Research design: Systematic literature search of CINAHL and Medline databases, Google Scholar, and Cochrane Database of Systematic Reviews, as well as grey literature search, was conducted. Search dates were restricted from January 2005 to 2015 in both CINAHL and Medline. Findings: 62 studies were identified, of which 6 qualitative research papers were included. Nurses gave varied definitions of patient advocacy, which were categorized into three themes: communication, protection, and doing. Nurses perceive advocacy as truly listening to patients and their families. Conclusion: For critical care nurses to be effective advocates, there must be support, collaboration, and improved working relationship between professional groups. Moreover, nurses must be empowered to be able to give power to patients and family.
ARTICLE | doi:10.20944/preprints201908.0035.v4
Subject: Engineering, Civil Engineering Keywords: PVA-ECC; vehicle-induced vibrations; setting periods; tensile performance; grey correlation analysis
Online: 7 August 2019 (03:35:46 CEST)
Polyvinyl alcohol-engineering cementitious composites (PVA-ECC) has been widely applied in bridge deck repairing or widening, the common practice for doing this is that a portion of a bridge is left open to traffic while the closed portion is constructed, which expose the early age PVA-ECC to the vehicle-induced vibrations. However, whether vehicle-induced vibrations affect the tensile performance of early age PVA-ECC remains unknow. The purpose of this study was to conduct laboratory test programs on how much vehicle-induced vibrations during early ages affected the tensile performance of PVA-ECC. A self-improved device was used to simulate the vehicle-induced vibrations, and after vibrating with the designed variables, both a uniaxial tensile test and a grey correlation analysis were performed. The results indicated that: the effects of vehicle-induced vibrations on the tensile performance of early age PVA-ECC were significant, and they generally tended to be negative in this investigation. In particular, for all of the vibrated PVA-ECC specimens, the most negative age when vibrated occurred during the period between the initial set and the final set. We concluded that although vehicle-induced vibrations during the setting periods had no substantial effects on the inherent strain-hardening characteristics of PVA-ECC, the effects should not be ignored.
ARTICLE | doi:10.20944/preprints202306.0317.v1
Subject: Social Sciences, Psychology Keywords: exhaustion; disability; illness; disorder; adopted child; adoptive parent; single mom; single dad
Online: 5 June 2023 (12:07:39 CEST)
Although early work on parental burnout in the 1980s did not link parental burnout to specific parenting situations, the idea that parents affected by specific vulnerability factors were particularly at risk of burnout quickly emerged. Based on the etiological model of parental burnout (i.e., the balance between risks and resources), the objective of this study was to determine if there were specific vulnerability factors that significantly increase the risk of parental burnout. 2,563 parents participated in the study. We compared parents with a child with special needs (n = 25), parents who had adopted a child (n = 130), and single parents (n = 109), to strictly matched control groups of parents. Parents with a child with special needs displayed higher burnout and lower balance between risk and resources than the control group; parents with an adopted child had similar levels of both parental burnout and balance; and single parents had higher parental burnout but similar balance. Parents who combined specific several vulnerability factors were at greater risk of burnout. Single parenthood and adoption do not in themselves trigger a process leading de facto to other risk factors, but having a child with special needs does.
REVIEW | doi:10.20944/preprints202004.0103.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Coronavirus; SARS-CoV-2; Medical Laboratory; Resource-limited setting, Good Laboratory Practice (GLP)
Online: 7 April 2020 (12:11:35 CEST)
The 2019 Coronavirus pandemic which was initially referred to as 2019-nCoV, was first identified in Wuhan, China. Early response from the Chinese government included quarantine of infected persons, isolation and total lockdown of Wuhan province to prevent further spread. With the spread of the disease across national borders and declaration of the disease as a global pandemic, there has been a robust response by the international community to contain this deadly virus and prevent its further spread worldwide. Africa is not left out of this rampaging pandemic with documented cases in over 40 countries and still rising. Although extensive studies have been carried out on the novel SARS-CoV-2 on its pathogenesis, mode of infection and virulence but much is still unknown. However, potentially infectious samples are received routinely in the medical laboratory for analysis. This technical note reviews good laboratory practice (GLP) and processes across the different specialities of Medical Laboratory practice that should minimize the risk of infection to laboratory staff especially in resource-limited settings.
REVIEW | doi:10.20944/preprints202001.0094.v1
Subject: Engineering, Civil Engineering Keywords: concrete setting time; Coca-cola; silica fume; fly ash; Plastocrete® RT6 Plus
Online: 10 January 2020 (06:55:02 CET)
During the casting in a warmer tropical temperature, a setting time delay is required to maintain the workability of the concrete, commonly achieved by the addition of admixtures i.e. silica fume (SF), fly ash (FA), and Plastrocrete®. However, high sugar content Coca-Cola in niche conditions is proposed as an ingredient for delaying concrete setting time in combination with conventional admixtures. This research aims to compare the setting time of admixtures from Coca-Cola and Plastocrete® RT6 plus in concrete mixing with control data of concrete mixed with SF or FA. The second aim is to measure the compression strengths between combinations of Coca-Cola and Plastocrete® RT6 plus. Concretes were produced with admixtures of SF, FA, Plastocrete® RT6plus, or Coca-Cola. The concrete used to control was f'c20 and f'c 25, while other concrete mixes were produced with the addition of Coca-Cola at 0.15% from the weight of cement at variation of moisture treatments. The first method to produce concrete (f'c20+Plas0.23%+Cola0.15% and f'c25+Plas0.23%+Cola0.15%) did not employ water reduction. The second concrete productions (f'c25+Plas0.46%+Cola0.15% and f'c25+Plas0.46%+Cola0.15%) reduced the addition of water at 8.8% (v/w). The first concrete production method had a setting time 44% longer than control. The reduced water concrete in the second productions had a setting time 34% longer than control. Meanwhile, the Plastocrete® RT6 Plus admixture with the reduced water delayed the concrete setting time by 26% longer than control. The delayed setting time of Plastocrete® RT6 Plus admixture with reduction of water was shorter than in the treatment with Coca-Cola. The combination of the addition of Coca-Cola with Plastocrete® RT6 plus by reducing the amount of adding Coca-Cola to 0.10% with Plastocrete® RT6 plus can delay concrete setting time by 51% longer than normal concrete and increase concrete compressive strength by 13% higher than normal concrete. Mixing Coca-Cola with Plastocrete® RT6 plus not only provided an optimal delay effect on setting time but also significantly increase the compressive strength that was desired during the casting in warm tropical weather applied in building construction of Mulawarman University, Samarinda, Indonesia.
ARTICLE | doi:10.20944/preprints201908.0264.v1
Subject: Business, Economics And Management, Business And Management Keywords: price-setting newsvendor, one-shot decision theory, innovative product, scenario, behavioral operations research
Online: 26 August 2019 (12:30:03 CEST)
In this paper, we consider a manufacturer who produces and sells a kind of innovative product in the monopoly market environment. Because the life cycle of innovative product is usually shorter than its procurement lead time, one unique demand quantity (scenario) will occur in the selling season, thus there is only one chance for the manufacturer to determine both optimal production quantity and optimal sale price. Considering this one-time feature of such a decision problem, a price-setting newsvendor model for innovative products is proposed. Different to the existing price-setting newsvendor models, the proposed models determine the optimal production quantity and sale price based on some specific state (scenario) which is most applicable for the manufacturer. The theoretical analysis provides managerial insights into the manufacturers’ behaviors in a monopoly market of an innovative product and several phenomena in the luxury goods market are well explained.
REVIEW | doi:10.20944/preprints202306.1276.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: Molecular magnetism; single-molecule magnets; carbon nanotubes; single-molecule magnets-carbon nanotubes hybrids.
Online: 19 June 2023 (03:38:58 CEST)
Single-molecule magnets (SMMs) have garnered significant interest in the field of molecular magnetism due to their unique magnetic properties at the nanoscale. These molecular systems exhibit magnetisation behaviour reminiscent of conventional bulk magnets but with distinct advantages such as size-dependent properties and potential applications in quantum computing and high-density data storage. However, challenges remain in harnessing their properties for practical applications, including their susceptibility to degradation and limited control over their assembly and organisation.
REVIEW | doi:10.20944/preprints202011.0741.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: folding; interactions; single-chain nanoparticles
Online: 30 November 2020 (16:20:43 CET)
The folding of certain proteins (e.g., enzymes) into perfectly defined 3D conformations via multi-orthogonal interactions is critical to their function. Concerning synthetic polymers chains, the “folding” of individual polymer chains at high dilution via intra-chain interactions leads to so-called single-chain nanoparticles (SCNPs). This review article describes the advances carried out in recent years in the folding of single polymer chains into discrete SCNPs via multi-orthogonal interactions using different reactive chemical species where intra-chain bonding only occurs between groups of the same species. First, we summarize results from computer simulations of multi-orthogonally folded SCNPs. Next, we comprehensively review multi-orthogonally folded SCNPs synthesized via either non-covalent bonds or covalent interactions. Finally, we conclude by summarizing recent research about multi-orthogonally folded SCNPs prepared through both reversible (dynamic) and permanent bonds.
ARTICLE | doi:10.20944/preprints202002.0221.v1
Online: 16 February 2020 (14:56:57 CET)
ACE2, the putative receptor for the novel coronavirus (2019-nCoV), played an important role in cell entry of 2019-nCoV. However, it is not yet clear what cell types within the human body express ACE2. Here, a systematic analysis was undertaken using published single cell datasets. In total, our study analyzed 229652 cells, from five different organs, derived from 88 donors. The top ACE2 expressing cells include proximal tubule cells in the kidney and enterocytes in the intestine. Other major ACE2 expressing cells in the kidney include podocytes, intercalated cells and endothelial cells. Our results offer a comprehensive atlas of ACE2 expression at the single cell level and unravel the enormous potential targets of 2019-nCoVinfection beyond the lung.
REVIEW | doi:10.20944/preprints201910.0351.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: photochemistry; photofolding; single-chain nanoparticles
Online: 30 October 2019 (09:03:24 CET)
Clean use of photons from light to activate chemical reactions offer many possibilities in different fields, from chemistry and biology to materials science and medicine. This review article describes the advances carried out in last decades toward the phototriggered synthesis of single-chain polymer nanoparticles (SCNPs) as soft nanomaterials with promising applications in enzyme-mimicking catalysis and nanomedicine, among other different uses. First, we summarize different strategies developed to synthesize SCNPs based on photoactivated intrachain homocoupling, phototriggered intrachain heterocoupling and photogenerated collapse induced by external cross-linker. Next, we comprehensively review the emergent topic of photoactivated multifolding applied to SCNP construction. Finally, we conclude by summarizing recent strategies towards phototriggered disassembly of SCNPs.
ARTICLE | doi:10.20944/preprints202307.1147.v1
Subject: Medicine And Pharmacology, Pharmacy Keywords: clinical pharmacist; pharmacist intervention; perioperative; surgical setting; potentially inappropriate medication; best possible medication history
Online: 18 July 2023 (04:15:38 CEST)
Background: Best Possible Medication History (BPMH) collected by clinical pharmacists is crucial for effective medication review but, in Italy, it is often left to the nursing staff. This study aims to compare the quality and accuracy of a clinical pharmacist-documented BPMH with the current standard practice of ward staff-collected BPMH at an Italian perioperative surgical setting. Methods: A 20-week prospective observational non-profit study was conducted in a major University hospital. The study comprised a feasibility, an observational, and an interventional phase. During the feasibility phase, 10 items for obtaining a correct BPMH were identified. The control group consisted of retrospectively analyzed BPMHs collected by the ward staff during the observational phase, while interventions included BPMHs collected by the clinical pharmacist during the third phase. Omissions between the two groups were compared. Results: 14 (2%) omissions were found in the intervention group, compared with 400 (57.4%) found in the controls (p<0.05); data collection was more complete when collected by pharmacists compared to the current modalities (98.0% versus 42.6%; p<0.05). Conclusions: The involvement of a pharmacist significantly reduced the number of omissions in perioperative surgical-collected BPMHs. This intervention holds the potential to decrease the risk of medication errors associated with inaccurate or incomplete BPMHs prior to surgical hospitalization.
ARTICLE | doi:10.20944/preprints201909.0106.v1
Subject: Computer Science And Mathematics, Information Systems Keywords: slot allocation; characteristics of slot wave; capacity setting; data feeding methods; linear integer programming
Online: 10 September 2019 (07:52:51 CEST)
Management of demand and capacity for airport operation is important. The effect of capacity setting on slot adjustment, maximum adjustment and flight delay has been extensively investigated and discussed in previous slot adjustment models. But its effect on characteristics of flight waves has not been studied deeply. At present, in order to resolve the problem that Linear Integer Programming (LIP) is limited in slot allocation due to its fast dimension growth and large memory consumption, the general practice is to optimize the slot application according to data-splitting technology. However, the relationship among data splitting method, capacity setting and characteristics of slot wave has not been investigated in detail, which limits the application of LIP in slot allocation. Through the detailed analysis and testing, we found that the waveform and amplitude of slot wave can be controlled and designed by appropriate virtual capacity settings, while the number of capacity constraints and the computing time is reduced by adopting appropriate data feeding method. Our research also provides clues for further research on the construction of the flight waves for airlines operating at specific airports in order to establish direct or indirect connectivity, and increase hit rate by using our approaches.
REVIEW | doi:10.20944/preprints201801.0075.v1
Subject: Public Health And Healthcare, Public, Environmental And Occupational Health Keywords: health promotion; ageing; workplace; occupational health; effectiveness; salutogenesis; holistic medicine; subsidiarity; participatory approach; setting
Online: 9 January 2018 (07:26:56 CET)
The ageing of workers is one of the most important issues for occupational health and safety in Europe. A number of intervention studies on health promotion for older workers were conducted in European workplaces between 2000 and 2015. This review gives an overview of these studies and considers perspectives for workplace health promotion.
ARTICLE | doi:10.20944/preprints202309.1578.v1
Subject: Social Sciences, Psychology Keywords: Internalizing Mental Health Problems; Externalizing Mental Health Problems Adolescence; Educational setting; Violence prevention; Gender issues
Online: 22 September 2023 (13:15:23 CEST)
Background/aim: Sexual harassment has become a serious social and public health problem in adolescence, causing adverse effects on mental health. Nevertheless, some behaviours arise that, due to their characteristics, might be misinterpreted as sexual harassment. A field study, a survey with a non-probabilistic accidental sampling, was designed in order to estimate the prevalence of sexual harassment victimization in the Spanish adolescent population, as well as to quantify the harms. Method: 1028 Spanish adolescents, 54.3% females and 45.7% males, aged 13-17 years (M = 15.21, SD = 1.03), responded to a diagnostic measure of sexual harassment victimization and an inventory measure of internalizing and externalizing Mental Health Problems (MHPs). Results: The results showed a significant prevalence of diagnosed sexual harassment victimization of school-aged adolescents, 24.1%, 95% [.215, 267], with adverse effects on internalizing and externalizing MHPs. As for the internalizing MHPs, the results showed moderate adverse effects on depression, anxiety, somatic burns, posttraumatic symptoms, and obsessive-compulsive symptoms; and mild adverse effects on social anxiety. With regard to externalizing MHPs, the results revealed moderate adverse effects on hyperactivity-impulsivity, anger control and antisocial behaviour; and mild adverse effects on attention problems, aggression and defiant behaviour. In addition, it was corroborated that sexual harassment victimization affects adolescent females to a greater extent, with the effect being significantly greater in internalizing than in externalizing MHPs. Conclusions: The results obtained are discussed and future lines of research and intervention are proposed to promote the implementation of prevention and intervention programs that address this phenomenon and, in turn, improve the physical, psychological, and social well-being of adolescents.
ARTICLE | doi:10.20944/preprints202308.0762.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: Zarit Burden Interview scale; burden of care; home care giving; severe mental illness; rural setting
Online: 10 August 2023 (05:32:21 CEST)
Jabulile Ndlovu1 and Kebogile Mokwena1, 2 1 Department of Public Health, Sefako Makgatho Health Sciences University, Pretoria, South Africa 2 Research Chair in Substance abuse and population Mental Health, Sefako Makgatho Health Sciences University, Pretoria, South Africa Corresponding author: firstname.lastname@example.org Abstract An estimated 6% of the world population has serious mental illness, with one in four families having a member with some form of psychiatric disorder, who are mostly cared for by their relatives within a family setting. Although caregiving in a home setting is reported to be associated with significant mental distress, the burden of such distress is rarely measured. The purpose of this study was to quantify the burden of care among family caregivers of relatives with serious mental disorders, as well as to explore possible association between the caregiver burden of care and a range of caregiver and Mental Health Care User (MHCU) variables in a rural district in Kwa-Zulu Natal, South Africa. The Zarit Burden Interview (ZBI) scale was used to collect data from 357 caregivers, and STATA 14 was used to analyze data. The ages of the sample ranged from 18 to 65, with a mean of 50.29, and the majority (86%) were female and unemployed (83%). The ZBI scores ranged from 8 to 85, with a mean of 41.59. The majority (91%) tested positive for caregiver burden of care, which ranged from mild to severe. Using the Pearson Chi-square test of association (p=0.05), variables that were significantly associated with the burden of care were clinically related (caregiver self-reported depression, MHCU diagnosis, recent relapse of the MHCU), socio-economic (caregiver family monthly income, MHCU disability grant status and MHCU employment status) and socio-demographic (MHCU gender and MHCU level of education). The prevalence of burden of care is high and severe, and scarcity of resources in families and communities contribute to the high burden of care in these rural communities.
ARTICLE | doi:10.20944/preprints202305.1916.v1
Subject: Medicine And Pharmacology, Pulmonary And Respiratory Medicine Keywords: High flow nasal cannula oxygen therapy; acute respiratory failure; geriatrics; acute non-intensive hospital setting
Online: 26 May 2023 (10:22:17 CEST)
Background. There are scant data about the effectiveness of high flow nasal cannula (HFNC) oxygen therapy in patients hospitalized with severe acute respiratory failure (ARF) in non-intensive medical wards, particularly regarding the effect on arterial oxygenation compared to conventional oxygen therapy (COT) and non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP). Methods. In a retrospective observational study, oxygenation parameters were measured before and immediately after HFNC initiation in 37 consecutive patients hospitalized in a geriatric ward in 2017. Results. HFNC was used as escalation therapy for untreatable hypoxia after failure of NIV/CPAP (n=18) or COT (n=19). Twenty-two patients died, 2 were transferred to the intensive care unit, while 13 were discharged alive. A “do not intubate” status was identified in 17 of the 22 deceased patients. Partial pressure of oxygen (pO2, p< 0.0001), oxygen saturation (SO2, p< 0.0001), pO2/fraction of inspired oxygen ratio (p=0.004) and peripheral SO2 measured by pulse oximetry (p< 0.0001) significantly increased soon after HFNC application. Oxygenation improvements were greater after escalation from NIV/CPAP and in patients discharged alive. Conclusion. HFNC significantly improved oxygenation in severe ARF after failure of COT or NIV/CPAP and may be particularly suitable for older patients hospitalized in non-intensive medical wards.
ARTICLE | doi:10.20944/preprints201811.0632.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: fault line detection; data fusion; non-artificial setting; sound distance; fault distance; resonant grounding system
Online: 30 November 2018 (10:38:18 CET)
Fault line detection timely and accurately when single-phase-to-earth fault occurs in resonant grounding system is still a focus of research. This paper presents a new approach for fault detection based on data fusion and it has non-artificial setting. Firstly, the fault criterion for interphase difference energy ratio and time-frequency correlation coefficient of each line is proposed. Subsequently, the paper establish a coordinate system with the interphase difference energy ratio as X axis and the time-frequency correlation coefficient as Y axis, and it uses the Euclidean distance algorithm to get the characteristic distance of each line by fusing two-dimensional information. Finally, comparing the sound distance and the fault distance of each line to discriminate the fault line. Electromagnetic Transients Program (EMTP) simulation results and adaptability analysis have confirmed the effectiveness and reliability of the proposed scheme.
ARTICLE | doi:10.20944/preprints202309.1070.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: human longevity; single nucleotide polymorphisms; Sardinia
Online: 18 September 2023 (07:02:09 CEST)
Background. In the central-eastern region of the Mediterranean island of Sardinia more than two decades ago, a mountain area was identified where the population displays exceptional longevity, especially among men (the longevity Blue Zone, LBZ). This community was thoroughly investigated seeking to understand the underlying factors of this phenomenon. In the present study, 11 genetic markers previously associated with longevity in several long-lived populations were analyzed. Methods. APOE (rs429358 and rs7412), APOE promoter (rs449647, rs769446, and rs405509), ACE1 (rs1799752), IL6 ‒174G/C (rs1800795), TNFα ‒308G/A (rs1800629), FOXO3A (rs2802292), KLOTHO (rs9536314) and G6PD (c.563C→T) were investigated. PCR-based genotyping was performed following genomic DNA extraction from 150 nonagenarians living in the LBZ and 150 controls from a nearby area. Results. No significant deviation of the frequency of the analyzed markers was detected between the two groups except a weak association with the –174G>C gene variant of the IL-6 gene (p=0.040), a major modulator of the inflammatory response. Conclusions. The findings of this study do not support a significant association of known genetic variants on survival in the population of the Sardinian LBZ. Other genetic or epigenetic traits might play a role not yet identified.
REVIEW | doi:10.20944/preprints202305.0151.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Epididymis; Regional; Single cell/Spatial Transcriptomics
Online: 3 May 2023 (12:43:28 CEST)
Sperm gain fertilization ability and forward movement characteristics during epididymal transport. Sperm maturation is inseparable from the processing of the epididymis. Compared with other reproductive organs, relatively little is known about the epididymis. However, with the development of molecular biology and the improvement of single-cell sequence technology, we gradually realized that we should re-examine the importance of the epididymis for sperm mat-uration and for the entire male reproductive system. Recently, epididymis related reports have tended to be more regionalized and more refined. We can understand cell distribution and gene expression from the perspective of a single cell. It has been reported that different regions of the epididymis have different functions and different cell compositions, which may be determined by gene expression. Here, we comprehensively reviewed the epididymal studies. From the ana-tomical structure of the epididymis to the division of its regions, we focused on the cell compo-sition and region-specific genes differentially expressed in the epididymis. The gene expression of the epididymis extends to a series of biological processes of sperm in the epididymal cavity, and the serious effects of epididymal diseases on reproduction are discussed. Therefore, the importance of the epididymis in male reproduction is emphasized. With the maturity of single-cell spatial transcriptomics, it is hoped that the technology can be applied to epididymal research and bring about the spatiotemporal landscape of the epididymis at the single-cell level.
ARTICLE | doi:10.20944/preprints202203.0090.v1
Subject: Physical Sciences, Optics And Photonics Keywords: strong coupling; nanoantenna; single quantum dot
Online: 7 March 2022 (07:49:51 CET)
The strong coupling between individual quantum emitters and resonant optical micro/nanocavities is beneficial to understand light and matter interactions. Here we propose a plasmonic nanoantenna placed on a metal film to achieve an ultra-high electric field enhancement in the nanogap and ultra-small optical mode volume. The strong coupling between a single quantum dot and the designed structure is investigated in detail by both numerical simulations and theoretical calculations. When a single QD is inserted into the nanogap of the silver nanoantenna, scattering spectra show remarkably large spectral splitting and typical anti-crossing behavior of the vacuum Rabi splitting, which can be realized in the scattering spectra by varying the nanoantenna thickness. Our work shows a possible way to enhance light-matter interaction at a single quantum emitter limit, which can be useful for future quantum and nanophotonic applications.
ARTICLE | doi:10.20944/preprints202009.0207.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: SMARTdenovo; single-molecule sequencing; genome assembly
Online: 9 September 2020 (10:48:24 CEST)
Long-read single-molecule sequencing has revolutionized de novo genome assembly and enabled the automated reconstruction of reference-quality genomes. It also has been widely used to study structural variants, phase haplotypes and more. Here, we introduce the assembler— SMARTdenovo, which is an SMS assembler that follows the overlap-layout-consensus (OLC) paradigm. SMARTdenovo (RRID: SCR_017622) was designed to be a fast assembler that did not require highly accurate raw reads for error correction, unlike other, contemporaneous SMS assemblers. It has performed well for evaluating congeneric assemblers and has been successful for a variety of assembly projects. It is compatible with Canu for assembling high-quality genomes, and several of the assembly strategies in this program have been incorporated into subsequent popular assemblers. The assembler has been in use since 2015, and here we provide information on the development of SMARTdenovo and how to implement its algorithms into current projects.
ARTICLE | doi:10.20944/preprints202008.0518.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Cattle; RNF128; RNF34; Single nucleotide polymorphisms
Online: 24 August 2020 (09:44:34 CEST)
An experiment was conducted to investigate the role of single nucleotide polymorphisms of the gene RNF34 3′UTR-588 G>A and RNF128 I1-2380C>T with carcass and meat quality traits of Chinese Simmental-cross steers. METHOD: We performed sequencing and restriction enzyme digestion to detect genotypes of RNF34 3′UTR-588 G>A and RNF128 I1-2380C>T. Then, we analyzed the association of novel single nucleotide polymorphisms in intron regions of the RNF128 gene and in the 3′UTR region of RNF34 and meat quality traits of Chinese Simmental-cross steers. RESULTS: Statistical analyses revealed that SNP of RNF128 (I1-2380C>T) was significantly associated with dressed weight, forepaw weight, carcass depth, carcass brisket depth, hind legs length (P<0.05), etc. And RNF34 (3′UTR-588 G>A) were significantly associated with testis weight, kidney weight, tare weight (P<0.05), etc. CONCLUSION: Our findings suggest that polymorphisms in RNF34 and RNF128 might be important genetic factors that influence carcass and meat quality in beef cattle. Thus, they might be useful markers for meat quality traits in future marker-assisted selection programs in beef cattle breeding and production.
ARTICLE | doi:10.20944/preprints202211.0018.v1
Subject: Medicine And Pharmacology, Orthopedics And Sports Medicine Keywords: stroke; occupational therapy; activities of daily living; goal setting; transcranial magnetic stimulation: upper extremity; motor paralysis
Online: 1 November 2022 (04:46:18 CET)
Repetitive transcranial magnetic stimulation (rTMS) with intensive occupational therapy improves upper limb motor paralysis and activities of daily living after stroke; however, amount of improvement according to paralysis severity remains unverified. Target activities for daily living using patients’ upper limb functions can be established by predicting the amount of change after treatment for each severity level of upper limb motor paralysis and further aid practice planning. This study estimated post-treatment score changes for each severity level of motor paralysis (no, poor, limited, notable, and full) stratified according to Action Research Arm Test (ARAT) scores before combined rTMS and intensive occupational therapy. Severity of motor paralysis was the fixed factor for analysis of covariance, delta (post-pre) of the scores was the dependent variable. Ordinal logistic regression analysis was used to compare changes in ARAT subscores in patients, divided according to paralysis severity before treatment. A multicenter retrospective cohort dataset analyzed 907 patients with stroke hemiplegia. Largest treatment-related changes in scores were observed in the Limited recovery group for upper limb motor paralysis and Full recovery group for quality-of-life activities using paralyzed upper limb. These results will help predict treatment effects and determine exercises and goal movements for occupational therapy after rTMS.
REVIEW | doi:10.20944/preprints202303.0371.v1
Subject: Medicine And Pharmacology, Hematology Keywords: Nuclei isolation; Next-generation sequencing; Cell-type specific isolation; Epigenetics; Transcriptomics; Single cell sequencing; Single nucleus sequencing
Online: 21 March 2023 (06:40:11 CET)
In the last decade, we have witnessed an upsurge in nuclei-based studies, particularly coupled with next-generation sequencing. Such studies aim at understanding the molecular states that exist in heterogeneous cell populations by applying increasingly more affordable sequencing approaches, in addition to optimized methodologies developed to isolate and select nuclei. Although these powerful new methods promise unprecedented insights, it is important to understand and critically consider the associated challenges. Here, we provide a comprehensive overview of the rise of nuclei-based studies and elaborate on their advantages and disadvantages. Improved designs and appropriate use of the various experimental strategies will result in acquiring biologically accurate and meaningful information.
ARTICLE | doi:10.20944/preprints202308.1843.v1
Subject: Physical Sciences, Applied Physics Keywords: single crystal; perovskite; synchrotron; MAPbBr3; optical property
Online: 28 August 2023 (09:52:48 CEST)
We fabricated high-quality MAPbBr3 single crystals (SC) by introducing moderate amount electron-rich poly(propylene glycol bis(2-aminopropyl ether) (PEA) additives with an inverse temperature crystallization (ITC) method. The intramolecular vibrations and defective states of prepared MAPbBr3 single crystals were systemically studied by the in situ variable-temperature Fourier Transform Infrared (FTIR) Spectroscopy, X-ray photoelectron spectroscopy (XPS), and the synchrotron-based X-ray absorption near edge structure (XANES), et al. We infer that the proper amount of PEA additives would prevent the formation of intermediate states and crystal boundaries, passivating the density of defective states. The X-ray detection properties of single-crystal MAPbBr3 crystals were investigated, using both high dose and low dose X-ray photons at 40keV in synchrotron beamlines. The photocurrent of optimized PEA-treated MAPbBr3 single crystals demonstrate better performance compared with the as-prepared single crystals. Meanwhile, the decay time of MAPbBr3 single crystal is decreased from 460 ns to 210 ns by Time-resolved photoluminescence (TRPL) decay measurement, owing to the defect passivation by 0.5wt% PEA additives. The PEA-treated single crystals possess much faster decay time than the commercialized Ce:YAG scintillator (>500ns). These results help elucidate the passivation of defective states and contribute paths to manufacture high-quality single crystal perovskites for next-generation optoelectronic devices.
COMMUNICATION | doi:10.20944/preprints202306.2148.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: Curcumin-Copper (II); single crystal; cytotoxicity; antioxidant
Online: 29 June 2023 (13:26:13 CEST)
The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L=curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.
ARTICLE | doi:10.20944/preprints202306.1079.v1
Subject: Medicine And Pharmacology, Pharmacy Keywords: lignans; cancer; single nucleotide polymorphisms; virtual screening
Online: 16 June 2023 (05:10:48 CEST)
Cancer is a multifactorial disease that continues to increase. Lignans are known to be important anticancer agents. However, due to the structural diversity of lignans, it is difficult to associate anticancer activity with a particular subclass. Therefore, the present study sought to evaluate the association of lignan subclasses with antitumor activity, considering the genetic profile of the variants of the selected targets. For this, predictive models were built against the targets tyrosine-protein kinase ABL (ABL), epider-mal growth factor receptor erbB1 (EGFR), histone deacetylase (HDAC), Serine/threonine-protein kinase mTOR (mTOR) and Poly [ADP-ribose] polymerase-1 (PARP1). Then, mapped single nucleotide polymorphisms and designed target mutations, and performed molecular docking with the lignans with the best predicted biological activity. The results showed more anticancer activity in the dibenzocyclooctadiene, furofuran and aryltetralin subclasses. The lignans with the best predictive values of biological activity showed varying binding energy results in the presence of certain genetic variants.
ARTICLE | doi:10.20944/preprints202305.1104.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: hemolytic uremic syndrome; complement; single cell sequencing
Online: 16 May 2023 (05:36:09 CEST)
Atypical hemolytic uremic syndrome (aHUS) is a rare and life-threatening disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury, necessitating differentiation from other thrombotic microangiopathy disorders. Definitive biomarkers for disease diagnosis and activity are currently lacking, and identifying molecular markers is essential. We conducted single-cell sequencing on peripheral blood mononuclear cells from 13 aHUS patients, 3 aHUS family members, and 4 healthy controls. Analysis included clustering, cell type annotation, pseudotime estimation, and cell-cell communication. Immune cell populations differ among aHUS, aHUS families, and healthy controls. Disease activity and treatment influence T, NK, B, and monocyte subpopulations, with increased intermediate monocyte levels distinguishing aHUS from controls and aHUS groups with varying disease activity. Subclustering revealed differential gene expression in patients compared to controls; higher expression of mitochondria-related genes suggests cell metabolism may influence clinical course. Pseudotime trajectory analysis demonstrated unique immune cell differentiation, and cell-cell interaction analysis identified distinct signaling pathways among patients, family members, and controls. This single-cell sequencing study is the first to confirm immune cell dysregulation in aHUS pathogenesis, offering valuable insights into molecular mechanisms and potential new diagnostic and disease activity markers.
ARTICLE | doi:10.20944/preprints202212.0476.v1
Subject: Physical Sciences, Applied Physics Keywords: Adiabatic; figure of merit; Heat engine; Single
Online: 26 December 2022 (06:50:12 CET)
A quantum Otto engine with a single ion harmonic oscillator as its working substance is studied for an adiabatic operation at high and low temperature limits. Using the universal optimization method, the heat engine is effectively optimized and found to yield better working conditions in some ranges of temperature ratios. Accordingly, the figure of merit, ψ, is found to be greater than unity in the range: 0<β2β1≤0.12; showing that the heat engine performs better in the optimized condition than in the maximum power working condition. ψ is determined to be less than one in the range 0.12≤β2β1≤0.35 under the same temperature limit ; depicting that the maximum power working condition is preferred to the optimized working condition. On the other hand, in the low temperature limit, the figure of merit, ψ, is found to be greater than unity in the range 3.7<ω1ω2≤18; revealing that optimized working condition is better than the maximum power working condition for the heat engine. In the same temperature limit, ψ is found to be less than one in the range 0≤ω1ω2≤3.7; showing that maximum power working condition is preferred to the optimized one. For the model of heat engine studied, in some ranges of temperature ratio, it is found to work better in the optimized condition, whereas in the other ranges it performs better under the maximum power working condition. So, it is possible to switch the engine between the two conditions depending on one’s need.
ARTICLE | doi:10.20944/preprints202108.0135.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; biomarker; TSPO; single nucleotide polymorphism; survival.
Online: 5 August 2021 (10:22:34 CEST)
Glioblastoma (GBM) is the most common primary brain tumor in adults, with few available therapies and a 5-year survival rate of 7.2%. Hence, strategies for improving GBM prognosis are urgently needed. The translocator protein 18kDa (TSPO) plays crucial roles in essential mito-chondria-based physiological processes and is a validated biomarker of neuroinflammation, which is implicated in GBM progression. The TSPO gene has a germline single nucleotide pol-ymorphism, rs6971, which is the most common SNP in the Caucasian population. High TSPO gene expression is associated with reduced survival in GBM patients; however, the relation between the most frequent TSPO genetic variant and GBM pathogenesis is not known. The present study ret-rospectively analyzed the correlation of the TSPO polymorphic variant rs6971 with overall and progression-free survival in GBM patients using three independent cohorts. TSPO rs6971 poly-morphism was significantly associated with shorter overall survival and progression-free survival in male GBM patients but not in females in one large cohort of 441 patients. We observed similar trends in two other independent cohorts. These observations suggest that the TSPO rs6971 pol-ymorphism could be a significant predictor of poor prognosis in GBM, with a potential for use as a prognosis biomarker in GBM patients. These results reveal for the first time a biological sex-specific relation between rs6971 TSPO polymorphism and GBM.
ARTICLE | doi:10.20944/preprints202101.0613.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: folding; single-chain nanoparticles; catalysis; click chemistry
Online: 29 January 2021 (11:51:41 CET)
“Clickase” single-chain nanoparticles (Ck-SCNPs) are folded, enzyme-mimetic unimolecular polymeric nano-objects containing copper (Cu) ions able to catalyze the azide-alkyne Huisgen cycloaddition reaction in water and/or selected organic solvents, often in the presence of a reductant. Herein, we investigate the effect of morphology on catalytic activity of Ck-SCNPs synthesized by means of two different routes. An amphiphilic random copolymer composed of oligo(ethylene glycol) methyl ether methyl methacrylate (OEGMA) and 2-acetoacetoxy ethyl methacrylate (AEMA) units was used as precursor of these Ck-SCNPs. Folding was promoted through metal complexation between Cu(II) ions and beta-ketoester-containing AEMA moieties. The first route resulted in Ck-SCNPs1 containing Cu ions homogeneously distributed within each nanoparticle, whereas the second one promoted intra-chain clustering of Cu ions inside Ck-SCNPs2. A model fluorogenic “click” reaction between 9-(azidomethyl)anthracene and phenylacetylene, which was catalyzed either by Ck-SCNPs1 or Ck-SCNPs2, was used to unravel the effect of morphology on catalytic activity. This work paves the way to improve the catalytic activity of metallo-folded SCNPs through control of the intra-chain distribution of catalytic sites.
REVIEW | doi:10.20944/preprints202004.0498.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: single cell protein; probiotic; actinomycetes; fermentation optimization
Online: 28 April 2020 (10:49:09 CEST)
Single cell proteins are the dead dried cells of microorganisms or purified protein isolated from microorganism’s cell culture, used as a food supplement to humans’ food and animals feed. World suffer from malnutrition particularly developing countries, due to rapid increase in population, increased the demand for protein and nutrients requirement. Bacteria is potential microorganism for SCP production due to high protein content, fast generation time, bio-active secondary metabolites production and can grow on various substrates. Actinobacteria species and strain have capability to produce biological active compounds, produced about two-thirds of antibiotics available in the market, actively used as antibiotics, antiprotozoal, antifungal, antiviral, anticancer, anticholesterol, antihelminth and immunosuppressant. Actinomycetes can be used as probiotic as well as single cell protein that will deal with antibiotic as well as protein source.
ARTICLE | doi:10.20944/preprints201807.0142.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: nanopore; peptide sensing; electrophysiology; single-molecule sequencing
Online: 9 July 2018 (13:26:06 CEST)
In this work we demonstrate the proof-of-concept of real-time discrimination between patches of serine or isoleucine monomers in the primary structure of custom-engineered, macro-dipole-like peptides, at uni-molecular level. We employed single-molecule recordings to examine the ionic current through the α-hemolysin (α-HL) nanopore, when hydrophilic serine or hydrophobic isoleucine residues, flanked by segments of oppositely charged arginine and glutamic amino acids functioning as a voltage-dependent ‘molecular brake’ on the peptide, were driven at controllable rates across the nanopore. The observed differences in the ionic currents blockades through the nanopore, visible at time resolutions corresponding to peptide threading through the α-HL’s constriction region, was explained by a simple model of the volumes of electrolyte excluded by either amino acid species, as groups of three serine or isoleucine monomers transiently occupy the α-HL. To provide insights into the conditions ensuring optimal throughput of peptide readout through the nanopore, we probed the sidedness-dependence of peptide association to and dissociation from the electrically and geometrically asymmetric α-HL.
ARTICLE | doi:10.20944/preprints201705.0155.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: single fiber; cutting; fracture morphology; failure mechanism
Online: 22 May 2017 (05:29:48 CEST)
The present study investigates the failure mechanisms of industrial fiber materials, using a custom designed fiber cutting performance test bench. The fracture morphologies of single PA6 fibers are examined by scanning electron microscopy. The analysis reveals that fiber cutting can be distinguished according to four distinct stages of fiber failure represented by shearing, cutting, brittle fracture, and tensile failure, which are the result of different mechanisms active during the processes of crack initiation, extension and fracture. The results of fractographic analysis are further verified by an analysis of the blade assembly speed with respect to time over the entire fracture failure process based on high-speed camera data. The results of fractographic analysis and blade assembly speed are fully consistent.
ARTICLE | doi:10.20944/preprints202302.0463.v1
Subject: Social Sciences, Education Keywords: Early childhood education; play and learning; educational transitions; educational setting; research with children; visual methodologies; qualitative research
Online: 27 February 2023 (09:03:38 CET)
Based on a reflection on the tensions between play, education, and learning in early childhood, this article aims to identify and analyze the factors that limit or negatively condition the possibilities for play at school during the transition between Early Childhood Education and Primary Education in Chile. The study was conducted in four Chilean schools, with the Transition Levels of Chilean Early Childhood Education (children aged 4 and 5) and the first two levels of Primary Education (children aged 6 and 7). Based on an ethnographic approach, we combined 22 ethnographic observation days spread over two consecutive years and 59 interviews of various types with children, educators, and parents. The results show structural-material limitations on school play that mainly affect children in Primary Education. Beyond, factors associated with routines, indications, and statements governing functioning and participation in this level tend to limit or prevent play, often considered a "non-legitimate" activity. Conclusions highlight the potentialities that children's restricted or resisted play can present in terms of learning.
ARTICLE | doi:10.20944/preprints202308.0266.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Carbon fiber; thermoset; sizing; single fiber tensile testing; single fiber pullout testing; sizing levels; X-ray photoelectron spectroscopy (XPS)
Online: 3 August 2023 (10:52:01 CEST)
It is well known that fiber sizing is one of the most important component in the manufacturing of composites, and it does affect the mechanical properties including strength and stiffness. In this work, the influence of fiber sizing levels on the mechanical properties of carbon fibers (CF) is reported at room temperature by using single fiber tensile testing (Favimat+), single fiber pullout testing (SFPO), and interfacial elemental analysis using X-ray photoelectron spectroscopy (XPS). Standard modulus of CF (7±0.2 μm in diameter) were sized using two Michelman commercially available sizing formulations. The average solid content for each sizing formulation is 26.3 ± 0.2% and 34.1 ± 0.2%, respectively. HEXION RIMR 135 with curing agent RIMH 137 was used as a model thermoset epoxy matrix during the SFPO measurements. A predictive engineering fiber sizing methodology is also developed. Sizing amounts of 0.5, 1, and 2 wt. % on the surface of the fiber is achieved for both sizing formulations. For each fiber sizing level, 50 single fiber tensile testing experiments and 20 single fiber pull-out tests were conducted. The ultimate tensile strength (σult) of the carbon fibers and the interfacial shear strength (τ_app) of the single fiber composite were analyzed. it is also investigated the effect of the sizing levels on the interfacial shear stress and the O/C (Oxygen/Carbon) surface composition ratio. As a result, generalized fiber sizing and characterization methods were established. The developed methods can be used to characterize the strength and interfacial shear strength of any man-made fibers with different sizing formulations and solid contents, irrespective of the matrix i.e. thermoset or thermoplastic.
ARTICLE | doi:10.20944/preprints202304.0773.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: Key words: transcriptome profiles; long non-coding RNAs; single-nucleotide polymorphisms; alternative splicing; sheep; preimplantation; Single-cell RNA sequencing
Online: 23 April 2023 (04:57:02 CEST)
Numerous dynamic and complicated processes characterize development from the oocyte to the embryo. However, given the importance of functional transcriptome profiles, long non-coding RNAs, single-nucleotide polymorphisms, and alternative splicing during embryonic development, the effect that these features have on the blastomeres of 2-, 4-, 8-, 16-cell, and morula stages of development have not been studied. Here, we conducted a scRNA-seq survey of cells from sheep from the oocyte to the blastocyst developmental stages. We then carried out experiments to identify and functionally analyze the transcriptome profiles, long non-coding RNAs, single-nucleotide polymorphisms (SNPs), and alternative splicing (AS). We founded that between the oocyte and zygote groups significantly down-regulated genes and the second-largest change in gene expression occurred between the 8- and 16-cell stages. We used various methods to construct a profile to characterize cellular and molecular features and systematically analyze the related GO and KEGG profile of cells of all stages from the oocyte to the blastocyst. This large-scale, single-cell atlas provides key cellular information and will likely assist clinical studies in improving preimplantation genetic diagnosis.
ARTICLE | doi:10.20944/preprints202306.2244.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: Produce prescription program; program implementation; food as medicine; fruit and vegetable consumption; healthcare setting; public health; diabetes; prediabetes.
Online: 30 June 2023 (11:37:43 CEST)
Through a partnership with three Federally Qualified Health Centers (FQHCs), the local health department in Los Angeles County implemented a produce prescription program (PPR) to increase fresh fruit and vegetable purchases among patients with diabetes or prediabetes. The PPR, which began in 2020, provided eligible patients with a $40 voucher every month for 6 months to promote the purchase of fresh produce at large chain grocery stores. This qualitative assessment describes staff experiences with the PPR, documenting the facilitators and barriers they encountered while implementing the program. Fifteen clinic staff (i.e., PPR implementers) were interviewed for this assessment. Thematic analysis and coding were conducted using the ATLAS.ti software; the coding was carried out by two separate coders. Interviewees discussed the importance of having preexisting partnerships and programs to support the PPR at their clinic site. Hidden costs related to implementing the program included a large and unexpected amount of staff time devoted to enrolling patients into the program. Collecting quality data and having limited expertise to rigorously evaluate the program were other challenges. Because patients often share their food with their family, the monthly $40 incentive was generally not enough to support their needs; interviewees suggested giving a higher inventive amount to those with a larger household. Future PPR efforts and similar food incentive programs should consider these and other facilitators and barriers to implementation and sustainability, especially when making adjustments to these programs to improve services and access to food resources.
ARTICLE | doi:10.20944/preprints202309.1833.v1
Subject: Computer Science And Mathematics, Computer Vision And Graphics Keywords: single image deraining; residual channel prior; interactive fusion
Online: 27 September 2023 (05:38:23 CEST)
Single image deraining (SID) has shown its importance in many advanced computer vision tasks. Though many CNN based image deraining methods have been proposed, how to effectively remove raindrops while maintaining background structure remains a challenge that needs to be overcome. Most of the deraining work focuses on removing rain streaks, but in heavy rain images, the dense accumulation of rainwater or the rain curtain effect significantly interferes with the effective removal of rain streaks, and often introduces some artifacts that make the scene more blurry. In this paper, we propose a new network structure R-PReNet for single image deraining with good background structure maintaining. This framework fully utilizes the cyclic recursive structure of PReNet. Moreover, we introduce residual channel prior (RCP) and feature fusion modules for better deraining performance by focusing on background feature information. Compared with the previous methods, our method has significantly improvement effect on the rainstorm image with the artifacts removing and good visual detail restoring.
COMMUNICATION | doi:10.20944/preprints202309.1293.v1
Subject: Physical Sciences, Optics And Photonics Keywords: SNSPD; multispectral; dual-spectral; single photon; quantum communication
Online: 20 September 2023 (02:29:29 CEST)
A multispectral superconducting nanowire single photon detector sensitive to different incident photon wavelength bands, is proposed. The SNSPD consists of a Distributed Bragg Reflector, a gold mirror, and two regions employing four NbN nanowires. Using the DBR both as a filter and a reflector, two distinct detection bands are created. The first detection band has a peak absorbance of > 0.75 at a wavelength of 1143 nm, while the second band has an absorbance of > 0.70 in the wavelength range 1440 to 2000 nm. The design of the device can be tuned to provide sensitivity in different wavelength bands. While SNSPDs do not typically provide photon wavelength sensitivity, the band-selection design proposed in this work opens up potential applications for future quantum communication technology.
BRIEF REPORT | doi:10.20944/preprints202308.0079.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Single nucleotide polymorphism, Population Branch Statistic, selective pressure.
Online: 1 August 2023 (10:37:24 CEST)
GDF5 gene is involved in the development of skeletal elements, synovial joint formation, tendons, ligaments, and cartilage. Several polymorphisms are present within the gene and two of them, rs143384 and 143383, have been reported as correlated with osteoarticular disease or muscle flexibility. The aim of this research is to verify if the worldwide distribution among human populations of rs143384 polymorphism has been shaped by selective pressure, or if it’s the result of random genetic drift events. Ninety-four individuals of both sexes, 18-28 years old, from Sardinia were analyzed. We observed the following genotype frequencies: 28.72% of homozygotes AA, 13.83% of homozygotes GG, and 57.45% of heterozygotes AG. Allele frequencies were 0.574 for allele A and 0.426 for alle G. Relationships between populations were verified by Multidimensional Scaling (MDS). Our data show: i) a clear heterogeneity within the African populations; ii) a strong differentiation between Africans and the other populations: iii) the Sardinian population is placed withing the European cluster. To reveal possible traces of selective pressure, Population Branch Statistic (PBS) was calculated; both SNPs rs143384 and 143383 have low PBS values, suggesting that there are no signals of selective pressure in those areas of the gene.
ARTICLE | doi:10.20944/preprints202305.0164.v1
Subject: Engineering, Civil Engineering Keywords: distributed fiber optics; tensile tests; single mode fiber
Online: 4 May 2023 (02:56:37 CEST)
The use of fiber optics as a tool for different kinds of geotechnical monitoring can become highly attractive and cost effective when compared to conventional instruments such as piezometers, inclinometers, among others. A single fiber optic cable may cover a larger monitoring area compared to conventional instrumentation, and the possibility of monitoring more than one physical quantity with the same fiber optic cable. Consulting the literature, it is possible to find several different examples where distributed fiber optic systems are being used. For the use of any sensor, a calibration curve is required. In the case of strain sensors, calibration is required to derive strain values from the frequency measurement quantity. However, fiber optic sensor cable manufacturers often do not provide their own calibration parameters and consult the values in specialized literature, which can result in monitoring errors. In this context, this article presents a bench adjusted for tests on single mode fiber optic cables, as well as results of tensile tests aimed at defining the function of strain variations of two different optical fiber cables, manufactured by different companies, using two different distributed interrogators. This paper also proposes a methodology for calibrating of the fiber optic cables deformation since the calibration parameters are provided by the cable manufacturers, which can result in errors depending on the application. It should be noted that there are few manufacturers of fiber optic cables aimed at application in civil engineering. Therefore, with the calibration methodology proposed in this paper, it is intended to transmit to the academic community the possibility of obtaining calibration parameters of any fiber optic cable, even those manufactured for telecommunications purposes and not only for cables manufactured with the intended use in civil engineering. Because of this fact, researchers will not be restricted to the acquisition of special cables for their applications. Based on the results, it was possible to conclude that the application of calibrated fiber optic sensors in experimental piles foundations is viable, in order to evaluate the load-displacement behavior of these elements, under different loading conditions.
ARTICLE | doi:10.20944/preprints202205.0106.v1
Subject: Environmental And Earth Sciences, Geophysics And Geology Keywords: seepage characteristics; single fracture; roughness; numerical simulation; Fluent
Online: 9 May 2022 (06:13:55 CEST)
A single fracture is the basic unit of fracture medium, and the roughness of fracture wall surface is an important factor influencing hydraulic characteristics of the ﬂow in bedrock fracture. However, effects of the shape and density of roughness elements (various bulges/pits on rough fracture wall surfaces) on water ﬂow in a single rough fracture have not been thoroughly discovered. Thus the water ﬂow in single fracture with different shapes and densities of roughness elements was simulated by using Fluent software in this study. The results show that in wider fractures the flow rate mainly depends on fracture aperture, while in narrow and close fracture medium the surface roughness of fracture wall is the main factor of head loss of seepage; there is a negative power exponential relation between the hydraulic gradient index and the average fracture aperture, i.e. with the increase of fracture aperture, the relative roughness of fracture and the influence weight of hydraulic gradient both decrease; and in symmetrical-uncoupled fractures there is a super-cubic relation between the discharge per unit width and average aperture. Above results would help to deepen the understanding of rough fracture seepage.
Subject: Physical Sciences, Acoustics Keywords: capillary; microfluidic device; single-molecule recycling; maximum likelihood
Online: 26 May 2021 (10:50:13 CEST)
Microfluidic devices have been extensively investigated in recent years in fields including ligand-binding analysis, chromatographic separation, molecular dynamics, and DNA sequencing. To prolong the observation of a single molecule in aqueous buffer, the solution in a sub-micron scale channel is driven by the electric field and reversed after a fixed delay following each passage, so that the molecule passes back and forth through the laser focus and the time before irreversible photobleaching is extended. However, this practice requires complex chemical treatment to the inner surface of the channel to prevent unexpected sticking to the surface and the confined space renders features, such as a higher viscosity and lower dielectric constant, which slow the Brownian motion of the molecule compared to the bulk liquid. In this paper, we have fixed a capillary microchannel with an inner diameter of 2 microns on top of a piezo stage to recycle the molecule and collected the fluorescence by a confocal microscope. The passing times of the molecule through the laser focus are calculated by a real-time control system based on an FPGA and the commands of translation are given to the piezo stage through a feedback algorithm. We have achieved a maximum number of recycles of more than 200 and developed a maximum-likelihood estimation of the diffusivity of the molecule, which attains results of the same magnitude as previous reports. This technique simplifies the overall procedure of the single-molecule recycling and could be useful for the ligand-binding studies of biomolecules.
ARTICLE | doi:10.20944/preprints202105.0562.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: MgAl2O4, Single atomic Nin+, RWGS, Stability, Reaction mechanism
Online: 24 May 2021 (10:50:17 CEST)
Reverse water gas shift reaction (RWGS) is an important process which plays a vital role in many CO2 utilization related reactions. Noble metals are the most active catalysts in RWGS, but the high price and low reserve strangled their applications. In the present work, we reported a non-transition-metal MgAl2O4 catalyst which showed outstanding activity and stability at high temperatures in the RWGS reaction and improved performance after doping of single atomic Nin+. The catalyst can obtain 46% of CO2 conversion in durability test of 75 h at 800 °C under high weight hourly space velocities (225 000 ml g-1 h-1). The adsorption sites, possible reaction route, and effects of Nin+ single atoms on the (111) surface of MgAl2O4 for RWGS were investigated by in situ DRIFTS and DFT calculations. The results indicated that the rate determining reaction step of RWGS on MgAl2O4 and Ni (SA)/MgAl2O4 were both the reaction of OH* + H* → H2O* + *, but the energy barrier was significantly reduced after introducing single atomic Nin+. Nin+ atoms can increase the hydroxyl coverage on the surface of catalyst and Al3+ sites near the Nin+ ion are considered as the predominant active sites for RWGS reactions.
ARTICLE | doi:10.20944/preprints202011.0704.v2
Subject: Chemistry And Materials Science, Biomaterials Keywords: single nanowires; Symmetry breaking; rectangular cross-section; absorption
Online: 8 February 2021 (11:38:12 CET)
Light absorption in single nanowires (NWs) is one of the most crucial factors for photovoltaic applications. In this paper, we carried out a detailed investigation of light absorption in single rectangular NWs (RNWs). We show that the RNWs exhibit improved light absorption compared with the square NWs (SNWs), which can be attributed to the symmetry-breaking structure that can increase the light path length by increasing the vertical side and the enhanced leaky mode resonances (LMRs) by decreasing the horizontal side. We found that the light absorption in silicon RNWs can be enhanced by engineering the horizontal and vertical sides, the photocurrent is significantly increased by 276.5% or 82.9% compared with that of the SNWs with the same side length as the horizontal side of 100 nm or the vertical side of 1000 nm, respectively. This work provides an effective way for designing high-efficiency single NW photovoltaic devices based on the symmetry breaking from the SNWs to RNWs.
ARTICLE | doi:10.20944/preprints202009.0712.v2
Subject: Chemistry And Materials Science, Biomaterials Keywords: silicon; single nanowires; elliptical cross-section; absorption; photocurrent
Online: 19 October 2020 (15:58:52 CEST)
Light trapping in single nanowires (NWs) are of vital importance for photovoltaic applications. However, circular NWs (CNWs) can limit its light-trapping ability due to high geometrical symmetry. In this work, we present a detailed study of light trapping in single NWs with an elliptical cross-section (ENWs). We demonstrate that the ENWs exhibit significantly enhanced light trapping compared with the CNWs, which can be ascribed to the symmetry-broken structure that can orthogonalize the direction of light illumination and the leaky mode resonances (LMRs). That is, the elliptical cross-section can simultaneously increase the light path length by increasing the vertical axis and reshape the LMR modes by decreasing the horizontal axis. We found that the light absorption can be engineered via tuning the horizontal and vertical axes, the photocurrent is significantly enhanced by 374.0% (150.3%, 74.1%) or 146.1% (61.0%, 35.3%) in comparison with that of the CNWs with the same diameter as the horizontal axis of 100 (200, 400) nm or the vertical axis of 1000 nm, respectively. This work advances our understanding of how to improve light trapping based on the symmetry breaking from the CNWs to ENWs and provides a rational way for designing high-efficiency single or self-assembled NW photovoltaic devices.
REVIEW | doi:10.20944/preprints201811.0596.v1
Subject: Biology And Life Sciences, Virology Keywords: HIV-1 assembly, Gag, single molecule microscopy, dynamics
Online: 26 November 2018 (14:12:08 CET)
HIV-1 assembly is a complex mechanism taking place at the plasma membrane of the host cell. It requires nice spatial and temporal coordination to end up with a full immature virus. Researchers have extensively studied HIV-1 assembly molecular mechanism during the past decades, in order to dissect the respective roles of viral proteins, viral genome and host cell factors. Nevertheless, the time course of the process has been observed in living cells only a decade ago. The very recent revolution of optical microscopy, combining high speed and high spatial resolution now permit to study assemblies and their consequences at the single molecule level within (living) cells. In this review, after a short description of these new approaches, we will show how HIV-1 assembly in cells has been revisited using these advanced super resolution microscopy techniques and how much it could make a bridge in studying assembly from the single molecule to the host cell.
ARTICLE | doi:10.20944/preprints201806.0371.v1
Subject: Physical Sciences, Applied Physics Keywords: optical tweezers; optical trap; PDMS devices; single cells
Online: 25 June 2018 (06:10:34 CEST)
Optical tweezers offer a non-contact method for selecting single cells and translocating them from one microenvironment to another. We have characterized the optical tweezing of yeast S. cerevisiae and can manipulate single cells at velocities up to 0.77 mm/s using laser powers of 40 mW from a 785 nm diode laser. We have fabricated and tested three cell isolation devices; a micropipette, a PDMS chip and laser machined fused silica chip and we have isolated single bacteria, yeast and cyanobacteria cells. The most effective isolation was achieved in PDMS chip, where single yeast cells were grown and observed for 18 hours without contamination. The duration of budding in S. cerevisiae was not affected by the laser parameters used, but the time from tweezing until the first budding event began increased with increase laser energy (laser power x time). Cells tweezed using 25 mW for 1 minute were viable after isolation. We have constructed a micro-consortium of yeast cells, and a co-culture of yeast and bacteria, using optical tweezers in combination with the PDMS network of channels and isolation chambers, which may impact on both industrial biotechnology and understanding pathogen dynamics.
ARTICLE | doi:10.20944/preprints201806.0183.v1
Subject: Physical Sciences, Condensed Matter Physics Keywords: FeSe2; high pressure; low temperature; single crystal diffraction
Online: 12 June 2018 (10:25:24 CEST)
We conducted an in-situ crystal structure analysis of ferroselite at non-ambient conditions. The aim is to provide a solid ground to further the understanding of the properties of this material in a broad range of conditions. Ferroselite, marcasite-type FeSe2, was studied under high pressures up to 46 GPa and low temperatures, down to 50 K using single-crystal microdiffraction techniques. High pressure and low temperatures were generated using a diamond anvil cell and a cryostat. We found no evidences of structural instability in the explored P-T space. The deformation of the orthorhombic lattice is slightly anisotropic. As expected, the compressibility of the Se-Se dumbbell, the longer bond in the structure, is larger than that of the Fe-Se bonds. Less obvious is the behavior of the octahedral bonds, the shorter bond is the most compressible determining a small increase in the octahedron distortion with pressure. We also achieved a robust structural analysis of ferroselite at low temperature in the diamond anvil cell. Structural changes upon temperature decrease are small but qualitatively similar to those produced by pressure.
REVIEW | doi:10.20944/preprints201709.0129.v1
Subject: Physical Sciences, Condensed Matter Physics Keywords: single crystal growth; incongruent melting compound; flux method
Online: 26 September 2017 (12:04:33 CEST)
Layered superconductors are attractive because some of them show high critical temperatures. While their crystal structures are similar, those compounds are composed of many elements. Compounds with many elements tend to be incongruent melting compounds, thus, their single crystals cannot be grown via the melt-solidification process. Hence, these single crystals have to be grown below the decomposition temperature, and then the flux method, a very powerful tool for the growth of these single crystals with incongruent melting compounds, is used. This review shows the flux method for single-crystal growth technique by self-flux, chloride-based flux, and HPHT (high-pressure and high-temperature) flux method for many-layered superconductors: high-Tc cuprate, Fe-based and BiS2-based compounds.
ARTICLE | doi:10.20944/preprints202309.2074.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: RAF1 aberration; amplification; fusion; single nucleotide variants; RAF inhibitor
Online: 29 September 2023 (10:33:00 CEST)
Purpose: Therapeutic targeting of RAF1 is promising, but it requires further investigation for the relation between clinical features and RAF1 aberrations regarding the MAPK signaling pathway in various solid tumors to realize the precision medicine. Methods: Between October 2019 and June 2023, Samsung Medical Center, 3,895 patients with metastatic cancer patients received a next-generation sequencing (NGS) using TruSight Oncology 500 (TSO500) assay as a routine clinical practice. We surveyed the incidence of RAF1 aberration including mutation (single-nucleotide variant [SNV]), amplification (copy-number variation), and fusion. Results: In 3,895 metastatic cancer patients, 77 (2.0%) had RAF1 aberrations in their tumor specimen. Of 77 patients, 44 (1.1%) had RAF1 mutations (SNV), 25 (0.6%) had RAF1 amplification and 10 (0.3%) had RAF1 fusions. Among 10 patients with RAF1 fusion, concurrent RAF1 amplification and RAF1 mutation were detected in one patient each. The most common tumor types were bladder cancer (11.5%), followed by ampulla of Vater (AoV) cancer (5.3%), melanoma (3.0%), gallbladder (GB) cancer (2.6%), and gastric cancer (2.3%). Microsatellite instability high (MSI-H) tumors were found in 5 out of 76 patients (6.6%) with RAF1 aberration, while MSI-H tumors were found only in 2.1% of patients with wild-type RAF1 cancer (p < 0.0001). Conclusion: We showed that when patients with metastatic solid cancer receive NGS test, approximately 2.0% have RAF1 aberrations in their tumor specimen.
ARTICLE | doi:10.20944/preprints202308.0832.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: Hardware acceleration; Convolutional Neural Networks; Single-Shot Multibox Detector
Online: 10 August 2023 (10:25:43 CEST)
Object detection is a popular image processing technique, widely used in numerous applications for detecting and locating objects in images or videos. While being one of the fastest algorithms for object detection, Single-Shot Multibox Detection (SSD) networks are also computationally very demanding, which limits their usage in real-time edge applications. Even though the SSD post-processing algorithm is not the most complex segment of the overall SSD object detection network, it is still computationally demanding and can become a bottleneck with respect to processing latency and power consumption, especially in edge applications with limited resources. When using hardware accelerators to accelerate backbone CNN processing, the SSD post-processing step implemented in software can become critical for high-end applications where high frame rates are required, as this paper shows. To overcome this problem, we propose Puppis, an architecture for hardware acceleration of SSD post-processing algorithm. As experiments will show, our solution will lead to an average SSD post-processing speedup of 34.42 when compared with a software implementation. Furthermore, execution of a complete SSD network will be on average 45.39 times faster than software implementation when the proposed Puppis SSD hardware accelerator is used together with some existing CNN accelerators.
ARTICLE | doi:10.20944/preprints202306.1799.v2
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: Epistasis; Homeostasis; Single segment substitution line; Heading date; Rice
Online: 31 July 2023 (09:42:16 CEST)
To avoid the endless accumulation of QTL effects during pyramiding breeding, QTL epistasis plays a role of homeostasis. Four single-segment substitution lines with heading date QTLs were utilized to construct pyramiding materials with dual QTLs and triple QTLs, allowing for the estimation of QTL epistatic effects on heading date in rice. The epistatic components of dual QTL and triple QTL interactions were analyzed using data from three seasons of two years. All four QTLs can be considered as dominant loci, demonstrating superdominance. 75% of dual QTL interactions and 81.25% of triple QTL interactions obtained statistically significant results, reaffirming the prevalence of epistasis. Interactions of four QTLs with three positive effects and one negative effect generated 62.5% negative dual QTL epistatic effects and 57.7% positive triple QTL epistatic effects, forming the balance relationship “positive-negative-positive”. In fact, QTL effects were consistently partially neutralized by mixed QTL epistatic effects so as to control the infinite accumulation of QTL effects. QTL epistasis plays a role of homeostasis on heading date in rice. However, there were two exceptions. The directions of OsMADS50 and Hd3a-2 effects were consistently aligned with those of their mixed epistases, suggesting that the QTL or gene could be employed in pyramiding breeding with different objectives. This study elucidated the mechanism of epistatic interactions among four QTLs and provided valuable genetic resources for improving heading date in rice.
ARTICLE | doi:10.20944/preprints202211.0475.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: single-atom catalysts; graphene; activity; reactivity; stability; Pourbaix plots
Online: 25 November 2022 (10:06:33 CET)
Understanding the catalytic performance of different materials is of crucial importance for further technological advancements. This especially relates to the behavior of different classes of catalysts under operating conditions. Here we analyze the effects of local coordination of metal centers (Mn, Fe, Co) in graphene-embedded Single-Atom Catalysts (SACs). We have started from well-known M@N4-graphene catalysts and systematically replaced nitrogen atoms with oxygen or sulfur atom to obtain M@OxNy-graphene and M@SxNy-graphene SACs (x+y=4). We show that local coordination strongly affects the electronic structure and the reactivity towards hydrogen and oxygen species. However, the stability is even more affected. Using the concept of Pourbaix plots, we show that the replacement of nitrogen atoms coordinating metal center with O or S destabilizes SACs towards the dissolution, while the metal centers get easily covered by O and OH acting as additional ligands at high anodic potentials and high pH values. Thus, not only should local coordination be considered in terms of the activity of SACs, but it is also necessary to consider its effects on the speciation of SACs' active centers under different potential and pH conditions.
ARTICLE | doi:10.20944/preprints202211.0129.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: 3D shapes; single-view reconstruction; gradient map; fine-grained
Online: 8 November 2022 (01:04:00 CET)
There has been considerable research on reconstructing 3D shapes from single-view images; however, preserving the detailed information of the input image remains difficult. In this paper, we propose the application of a gradient map to train a network, aimed at improving the visual quality of fine-grained details such as the thin and tiny components of generated shapes. Each gradient map was created from the original voxel data, and each value represented the amount of information per volume. Here, the gradient map was defined by several methods that mathematically quantify and represent the detailed structure of an object. By applying this map to the loss function in training, we could induce the network to intensively train partial details, such as thin and narrow parts. We demonstrated that the detailed information was well-recovered when a weight that is proportional to the gradient value was applied to the loss. Furthermore, it is expected that our method will contribute to the development of 3D technologies related to the construction of virtual space for simulation and new customer experience.
ARTICLE | doi:10.20944/preprints202206.0387.v1
Subject: Computer Science And Mathematics, Computational Mathematics Keywords: Exponentially–fitted; Obrechkoff; Fourth–derivative; Oscillatory; Periodic; Single–step
Online: 28 June 2022 (12:50:23 CEST)
The quest for accurate and more efficient methods for solving periodic/oscillatory problems is gaining more attention in recent time. This paper presents the construction and implementation of a family of exponentially–fitted Obrechkoff methods. A single–step Obrechkoff method involving terms up to the fourth derivatives was used as the base method. We also present the stability and convergence properties of the constructed family of methods. Two numerical examples were use to illustrate the performance of the constructed methods.
DATA DESCRIPTOR | doi:10.20944/preprints202205.0230.v1
Subject: Computer Science And Mathematics, Data Structures, Algorithms And Complexity Keywords: Single Image Super-Resolution; Sentinel-2; VENµS; remote sening
Online: 17 May 2022 (11:13:47 CEST)
Boosted by the progress in deep learning, Single Image Super-Resolution (SISR) has gained a lot of interest in the Remote Sensing community, who sees it as an oportunity to compensate for satellite's ever-limited spatial resolution with respect to end users needs. While there has been a great amount of work on network architures in the latest years, deep learning based SISR in remote sensing is still limited by the availability of the large training sets it requires. The lack of publicly available large datasets with the required variability in terms of landscapes and seasons pushes researchers to simulate their own dataset by means of downsampling. This may impair the applicability of the trained model on real world data at the target input resolution. In this paper, we propose an open-data licenced dataset composed of 10m and 20m cloud-free surface reflectance patches from Sentinel-2, with their reference spatially-registered surface reflectance patches at 5 meter resolution acquired on the same day by the VENµS satellite. This dataset covers 29 locations on earth with a total of 132 955 patches of 256x256 pixels at 5 meters resolution, and can be used for the training of super-resolution algorithms to bring the spatial resolution of 8 of the Sentinel-2 bands down to 5 meters.
COMMUNICATION | doi:10.20944/preprints202201.0389.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Weyl semimetal; NbAs single crystal; CVT; seed growth process
Online: 25 January 2022 (17:21:18 CET)
A Weyl semimetal is a novel crystal with low-energy electronic excitations that behave as Weyl fermions. It has received worldwide interest and was believed to have opened the next era of condensed matter physics after graphene and three-dimensional topological insulators. Howev-er, it is not easy to obtain a single large-size crystal because there are many nucleations in the preparation process. Here, a bottom-seed CVT growth method is proposed in this paper, and we acquired the large-size, high-quality NbAs single crystals up to 5x4x4 mm3 finally. X-ray diffrac-tion and STEM confirmed that they are tetragonal NbAs, which the key is to use seed crystal in vertical growth furnace. Notably, the photoelectric properties of the crystal are obtained under the existing conditions, which paves the way for the follow-up work.
REVIEW | doi:10.20944/preprints202111.0203.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: flower development; epigenetics; RNA biology; Genomics; single cell biology
Online: 10 November 2021 (11:00:03 CET)
The rise of data science in biology stimulates interdisciplinary collaborations to address fundamental questions. Here, we report the outcome of the first SINFONIA symposium focused on revealing the mechanisms governing plant reproductive development across biological scales. The intricate and dynamic target networks of known regulators of flower development remain poorly understood. To analyze development from the genome to the final floral organ morphology, high-resolution data that capture spatiotemporal regulatory activities are necessary and require advanced computational methods for analysis and modeling. Moreover, frameworks to share data, practices and approaches that facilitate the combination of varied expertise to advance the field are called for. Training young researchers in interdisciplinary approaches and science communication offers the opportunity to establish a collaborative mindset to shape future research.
ARTICLE | doi:10.20944/preprints202107.0597.v1
Subject: Public Health And Healthcare, Physical Therapy, Sports Therapy And Rehabilitation Keywords: 3D printing; microfabrication; microfluidic guillotine; single cell; wound healing
Online: 27 July 2021 (09:21:04 CEST)
Micro-blade design is an important factor in the cutting of single cells and other biological structures. This paper describes the fabrication process of three dimensional (3D) micro-blades for the cutting of single cells in a microfluidic “guillotine” intended for fundamental wound repair and regeneration studies. Our microfluidic guillotine consists of a fixed 3D micro-blade centered in a microchannel to bisect cells flowing through. We show that the Nanoscribe two-photon polymerization direct laser writing system is capable of fabricating complex 3D micro-blade geometries. However, structures made of the Nanoscribe IP-S resin have low adhesion to silicon, and they tend to peel off from the substrate after at most two times of replica molding in poly(dimethylsiloxane) (PDMS). Our work demonstrates that the use of a secondary mold replicates Nanoscribe printed features faithfully for at least 10 iterations. Finally, we show that complex micro-blade features can generate different degrees of cell wounding and cell survival rates compared with simple blades possessing a vertical cutting edge fabricated with conventional 2.5D photolithography. Our work lays the foundation for future applications in single cell analyses, wound repair and regeneration studies, as well as investigations of the physics of cutting and the interaction between the micro-blade and biological structures.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Proteomics, protein informatics, mass spectrometry, single cell, copy number
Online: 5 July 2021 (16:09:09 CEST)
Proteomic technology has improved at a staggering pace in recent years, with even practitioners challenged to keep up with new methods and hardware. The most common metric used for method performance is the number of peptides and proteins identified. While this metric may be helpful for proteomics researchers shopping for new hardware, this is often not the most biologically relevant metric. Biologists often utilize proteomics in the search for protein regulators that are of lower relative copy number in the cell. In this review, I re-evaluate untargeted proteomics data using a simple graphical representation of the absolute copy number of proteins present in a single cancer cell as a metric. By comparing single shot proteomics data to the coverage of the most in-depth proteomic analysis of that cell line acquired to-date we can obtain a rapid metric of method performance. Using a simple copy number metric allows visualization of how proteomics has developed in both sensitivity and overall dynamic range when using both relatively long and short acquisition times. To enable reanalysis beyond what is presented here, two available web applications have been developed for single and multi-experiment comparisons with reference protein copy number data for multiple cell lines and organisms.
REVIEW | doi:10.20944/preprints202104.0720.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: High Gain, Single Stage, Switched Inductor Buck Boost Converter
Online: 27 April 2021 (12:51:21 CEST)
In this research paper, a high gain transformer less inverter modeling which is used for the smart grid technology or as the stand alone for home appliances is proposed. The proposed transformer less topology provides a higher voltage gain, low cost, small size and simple control stand alone transformer less inverter for home appliances. The above inverter is modeled by using software which is known as MATLAB/ Simulimk.
ARTICLE | doi:10.20944/preprints202104.0563.v1
Subject: Physical Sciences, Acoustics Keywords: Single crystal diamond; micro-water jet guided laser; microchannel
Online: 21 April 2021 (09:05:14 CEST)
Two types of trenches cross-section in conventional vertical and brand new reverse-V-shape have fabricated on SCD substrate by micro-jet water-assist laser, the epitaxial lateral overgrowth technique has applied by microwave plasma chemical vapor deposition system in forming multiple micrometer-size channels. Raman and SEM techniques have applied in analyze both types growth layer characterization. Optical microscope has used to test microchannels hollowness. As a result, with the brand new reverse-V-shape trench, epitaxial lateral overgrowth layer reaches higher SCD surface morphology and crystal quality.
ARTICLE | doi:10.20944/preprints202103.0514.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: nanopore tweezer; peptide nucleic acid; sequencing; single molecule recordings
Online: 22 March 2021 (11:08:30 CET)
Quantum leaps advances in the single-molecule investigative science have been made possible over the past decades through the implication of nanopores, as versatile components on dedicated biosensors. Here, we employed the nanopore-tweezing technique to capture amino acid-functionalized, peptide-nucleic acids (PNA) with -hemolysin-based nanopores, and correlate the ensuing stochastic fluctuations of the ionic current through the nanopore with the composition and order of bases in the PNAs primary structure. We demonstrate that while the system enables detection of distinct bases on homopolymeric PNA or triplet bases on heteropolymeric strands, it also reveals rich insights into the conformational dynamics of the entrapped PNA within the nanopore, relevant for perfecting the recognition capability single-molecule sequencing.
ARTICLE | doi:10.20944/preprints202103.0196.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Single cell RNA-seq; spatial reconstruction; development; coalescent embedding
Online: 5 March 2021 (21:21:59 CET)
Single cell RNA-seq (scRNA-seq) profiles conceal temporal and spatial tissue developmental information. De novo reconstruction of single cell temporal trajectory has been fairly addressed, but reverse engineering single cell 3D spatial tissue localization is hitherto landmark based, and de novo spatial reconstruction is a compelling computational open problem. Here we show that a new algorithm - named D-CE - for coalescent embedding of single cell transcriptomic networks can address this open problem. We rely merely on the spatial information encoded in the expression patterns of developmental signal transcription factor (DST) genes, and we find that D-CE of cell-cell association DST-transcriptomic networks reliably reconstructs the Geo-seq or single cell samples’ 3D spatial tissue distribution. Comparison to the novoSpaRC and CSOmap (recent and only available de novo 3D spatial reconstruction methods) on 16 datasets and 681 reconstructions, reveals a significantly distinctive superior performance of D-CE.
ARTICLE | doi:10.20944/preprints202008.0258.v2
Subject: Chemistry And Materials Science, Nanotechnology Keywords: single nanowires; silicon; dual shells; off-resonance; absorption; photocurrent
Online: 31 August 2020 (08:30:22 CEST)
Single nanowires (NWs) are of great importance for optoelectronic applications, especially solar cells serving as powering nanoscale devices. However, weak off-resonant absorption can limit its light-harvesting capability. Here, we propose a single NW coated with the graded-index dual shells (DSNW). We demonstrate that with appropriate thickness and refractive index of the inner shell, the DSNW exhibits significantly enhanced light trapping compared with the bare NW (BNW), and the NW only coated with the outer shell (OSNW) and the inner shell (ISNW), which can be attributed to the optimal off-resonant absorption mode profiles due to the improved coupling between the reemitted light of the transition modes of the leak mode resonances of the Si core and the nanofocusing light from the dual shells with the graded refractive index. We found that the light absorption can be engineered via tuning the thickness and the refractive index of the inner shell, the photocurrent density is significantly enhanced by 134% (56%, 12%) in comparison with that of the BNW (OSNW, ISNW). This work advances our understanding of how to improve off-resonant absorption by applying graded dual-shell design and provides a new choice for designing high-efficiency single NW photovoltaic devices.
ARTICLE | doi:10.20944/preprints202008.0626.v1
Subject: Engineering, Civil Engineering Keywords: multispectral lidar; single-photon lidar; building data; 3D reconstruction
Online: 28 August 2020 (08:49:07 CEST)
This paper investigated building data from multispectral and single-photon Lidar systems. The multispectral datasets from the individual channels and fused channels were explored. The multispectral and single-photon Lidar data were compared across multiple aspects: the data acquisition geometry, number of echoes, intensity, density, resolution, data defects, noise level, and the absolute and relative accuracy. In addition, we explored the performance of the multispectral and single-photon data for roof plane detection for eight complex/stylish buildings to investigate the suitability of these data for 3D building reconstruction. The building data from the single-photon and multispectral Lidar systems were evaluated with respect to the reference building vector data with an accuracy of better than 5 cm. The advantages and disadvantages of both technologies and their applications in the urban building environment are discussed.
REVIEW | doi:10.20944/preprints202002.0215.v1
Subject: Chemistry And Materials Science, Electrochemistry Keywords: hydrogen evolution reaction; catalysis; supported catalysts; single atom catalysts
Online: 16 February 2020 (12:57:18 CET)
Hydrogen evolution reaction (HER) is one of the most important reaction in electrochemistry. This is not only because it is the simplest way to produce high purity hydrogen and the fact that it is the side reaction in many other technologies. HER actually shaped current electrochemistry because it was in focus of active research for so many years (and it still is). The number of catalysts investigated for HER is immense, and it is impossible to overview them all. In fact, it seems that the complexity of the field overcomes the complexity of HER. The aim of this review is to point out some of the latest developments in HER catalysis, current directions and some of the missing links between a single crystal, nanosized supported catalysts and, recently emerging, single atom catalysts for HER
ARTICLE | doi:10.20944/preprints201907.0218.v1
Subject: Computer Science And Mathematics, Applied Mathematics Keywords: Heaviside function, single valued function, real variable, integer part
Online: 18 July 2019 (14:34:55 CEST)
In this paper, the author obtains an analytic exact form of Heaviside function, which is also known as Unit Step function and constitutes a fundamental concept of the Operational Calculus.In particulat, this function is explicitly expressed in a very simple manner by the aid of purely algebraic representations. The novelty of this work is that the proposed explicit formula is not performed in terms of non – elementary special functions, e.g. Dirac delta function or Error function and also is neither the limit of a function, nor the limit of a sequence of functions with point wise or uniform convergence. Hence, it may be much more appropriate and useful in the computational procedures which are inserted into Operational Calculus techniques and other engineering practices.
ARTICLE | doi:10.20944/preprints201809.0069.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: Single-atom catalysis; heterogeneous catalysis; chemical innovation; low atomicity
Online: 4 September 2018 (14:55:10 CEST)
Recent advances in single-atom catalysis resulted in readily accessible materials whose application in most catalytic reactions mediated by conventional nanoparticle-based catalysts often results in higher activity and selectivity. Can we expect catalysis by atomically dispersed atoms to find practical applications? Which are the hurdles to be overcome prior to widespread uptake of atomically dispersed metals in industrial synthetic processes and in hydrogen fuel cells?
ARTICLE | doi:10.20944/preprints201808.0407.v1
Subject: Engineering, Control And Systems Engineering Keywords: angle estimation; microsoft kinect; single camera; markerless mocap system
Online: 23 August 2018 (05:55:56 CEST)
The use of motion capture has increased from last decade in a varied spectrum of applications like film special effects, controlling games and robots, rehabilitation system, animations etc. The current human motion capture techniques use markers, structured environment, and high resolution cameras in a dedicated environment. Because of rapid movement, elbow angle estimation is observed as the most difficult problem in human motion capture system. In this paper, we take elbow angle estimation as our research subject and propose a novel, markerless and cost-effective solution that uses RGB camera for estimating elbow angle in real time using part affinity field. We have recruited five (5) participants of (height, 168 ± 8 cm; mass, 61 ± 17 kg) to perform cup to mouth movement and at the same time measured the angle by both RGB camera and Microsoft Kinect. The experimental results illustrate that markerless and cost-effective RGB camera has a median RMS errors of 3.06° and 0.95° in sagittal and coronal plane respectively as compared to Microsoft Kinect.
REVIEW | doi:10.20944/preprints201805.0142.v2
Subject: Chemistry And Materials Science, Nanotechnology Keywords: graphene; cold field emission; single-tip cathode; electron microscopy
Online: 28 May 2018 (09:02:44 CEST)
Although good field emission from graphene has been demonstrated from a wide variety of different microfabricated structures, very few of them can be used to improve the design of cold field emitters for electron microscopy applications. Most of them consist of densely packed nano-emitters, which produce a large array of defocused overlapping electron beams, and therefore cannot be subsequently focused down to a single nanometer electron probe. This paper reviews the kind of single-tip cathode structures suitable in cold field emission guns for instruments such as scanning electron microscopy, transmission electron microscope or scanning transmission electron microscopy, and reviews progress in fabricating them from graphene-based materials.
ARTICLE | doi:10.20944/preprints201805.0212.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: polymer electrolyte; single-ion conducting; ionic conductivity; Raman spectroscopy
Online: 15 May 2018 (08:45:58 CEST)
Solvent-free, single-ion conducting electrolytes are sought after for use in electrochemical energy storage devices. Here, we investigate the ionic conductivity and how this property is influenced by segmental mobility and conducting ion number in crosslinked single-ion conducting polyether-based electrolytes with varying tethered anion and counter-cation types. Crosslinked electrolytes are prepared by the polymerization of poly(ethylene glycol) diacrylate (PEGDA), poly(ethylene glycol) methyl ether acrylate, and ionic monomers. The ionic conductivity of the electrolytes is measured and interpreted in the context of differential scanning calorimetry and Raman spectroscopy measurements. A lithiated crosslinked electrolyte prepared with PEG31DA and STFSI monomers is found to have a lithium ion conductivity of 3.2 × 10-6 and 1.8 × 10−5 S/cm at 55 and 100 °C, respectively. The percentage of unpaired anions for this electrolyte was estimated at about 23% via Raman spectroscopy. Despite the large variances in metal cation – STFSI binding energies as predicted via DFT and large variations in ionic conductivity, STFSI-based crosslinked electrolytes with the same charge density and varying cations (Li, Na, K, Mg, and Ca) were estimated to all have unpaired anion populations in the range of 19 to 29%.
ARTICLE | doi:10.20944/preprints201803.0081.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: multilevel; inverter; single phase; reduced switch-count; h-bridge
Online: 12 March 2018 (06:46:12 CET)
The past two decades has seen a growing demand for high-power, high-voltage utility scale inverters mostly fueled by the integration of large solar PV and wind farms. Multilevel inverters have emerged as the industry choice for these megawatt range inverters because their reduced voltage stress, capable of generating an almost sinusoidal voltage, in-built redundancy, among others. This paper present a new Switched-Source Multilevel Inverter (SS MLI) architecture. The new inverter show superior over existing topologies. It has reduced voltage stress on the semiconductor, uses less number of switches –reduced size/weight/cost and increased efficiency. The new SSMLI is comprised of two voltage sources (V1, V2) and 6 switches. It is capable of generating 5-level output voltage in symmetric modes (i.e., V1 = V2), and 7-level output voltage in asymmetric modes (i.e., V1 ≠ V2). To demonstrate the validity of the proposed inverter, simulations results using MATLAB® /Simulink® for 5- and 7-level output voltages are presented . The simulations are also verified experimentally using a laboratory prototype.
ARTICLE | doi:10.20944/preprints201608.0238.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: anisotropic exchange; single molecule magnets; Spin Hamiltonian; CASSCF; NEVPT2
Online: 31 August 2016 (10:56:43 CEST)
The rationalization of single molecule magnets’ (SMMs) magnetic properties by quantum mechanical approaches represents a major task in the field of the Molecular Magnetism. The fundamental interpretative key of molecular magnetism is the phenomenological Spin Hamiltonian and the understanding of the role of its different terms by electronic structure calculations is expected to steer the rational design of new and more performing SMMs. This paper deals with the ab initio calculation of isotropic and anisotropic exchange contributions in the Fe(III) dimer [Fe2(OCH3)2(dbm)4]. This system represents the building block of one of the most studied Single Molecule Magnets ([Fe4RC(CH2O)3)2(dpm)6] where R can be an aliphatic chain or a phenyl group just to name the most common functionalization groups) and its relatively reduced size allows the use of a high computational level of theory. Calculations were performed using CASSCF and NEVPT2 approaches on the X-ray geometry as assessment of the computational protocol, which has then be used to evinced the importance of the outer coordination shell nature through organic ligand modelization. Magneto-structural correlations as function of internal degrees of freedom for isotropic and anisotropic exchange contributions are also presented, outlining for the first time the extremely rapidly changing nature of the anisotropic exchange coupling.
ARTICLE | doi:10.20944/preprints202108.0275.v1
Subject: Social Sciences, Decision Sciences Keywords: Healthcare Priority-setting; Health Technology Assessment; Essential Health Packages, Low to Middle Income Countries; Equity; Efficiency; Evidence-Informed Decision Making
Online: 12 August 2021 (13:14:51 CEST)
There is a systematic exclusion of gender-based violence, safe abortion, reproductive cancers, infertility services, comprehensive sexuality education, sexuality services, and STI’s other than HIV in essential health packages in LMICs. To accelerate progress on sexual reproductive health (SRH), the Guttmacher–Lancet Commission proposed the adoption of these interventions into an essential health package of SRH services that should be universally available. In this commentary, we use a healthcare priority-setting processes lens to review the importance of these services for universal health coverage. We isolate inherent challenges in social value judgments for terminal, process and content evidence for their healthcare priority-setting. We then advance promising emerging practical examples from low to middle-income countries on evidence-informed decision-making processes. We recommend capacity development through regional support, generating equity and efficiency evidence and strengthening political and publicly acceptable processes to institutionalise and operationalise evidence-informed decision-making.
ARTICLE | doi:10.20944/preprints202307.0850.v1
Subject: Social Sciences, Gender And Sexuality Studies Keywords: Single Parenting; Adolescent Girls; Economic Impact; Academic Performance; Gambella; Ethiopia
Online: 12 July 2023 (12:12:11 CEST)
Single parenting is a social phenomenon that has always been in existence and is as old as mankind, and today the number of single-parent families has been rampantly increasing. As a result, the researcher conducted a study in the Gambella region of Ethiopia to investigate the economic and educational implications of single parenting on female adolescent students. The study employed a qualitative research approach with a case study research design. The researchers used the purposive sampling technique to select the research area and research participants for in-depth interviews and focus group discussions, and eleven interviewees, seventeen participants in focus group discussions within two groups, and seven key informants participated. Interviews were audio-recorded, transcribed, translated, and thematically analyzed. Interviews with research participants revealed that adolescent girl students from single-parent homes experience financial difficulties. The study also explored that students with single parents are more likely to be absent from school, to come late to school, to score low marks, and to drop out of school. Therefore, having an understanding of the benefits of having intact parents for the well-being of adolescents and raising children together should be advocated.
ARTICLE | doi:10.20944/preprints202306.0958.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: graphene nano-ribbon FET; single event upset; SRAM; stability; FinFET
Online: 13 June 2023 (16:22:35 CEST)
In recent years, graphene has received so much attention because of its superlative properties and its potential to revolutionize electronics especially in VLSI. This study analyzes the effect of single event upset (SEU) in SRAM cell which employs metal-oxide semiconductor type graphene nano-ribbon field effect transistor (MOS-GNRFET) and compares the results respectively with another SRAM cell designed in PTM 10nm FinFET node. Our simulation show there is a change in data stored in the SRAM after heavy ion strike. However, it recovers from radiation effects after 0.46 ns for GNRFET and 0.51 ns for FinFET. Since the degradation observed in Q and Qb of GNRFET SRAM are 2.7X and 2.16X as compared to PTM nano-MOSFET, we can conclude that GNRFET is less robust to single effect upset. In addition, the stability of SRAM can be improved by increasing the supply voltage VDD.
REVIEW | doi:10.20944/preprints202209.0327.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: scRNA-seq; bioinformatics; subpopulations; analysis methods; single-cell RNA sequencing
Online: 21 September 2022 (11:22:50 CEST)
Single-cell RNA sequencing data facilitates investigation of cell heterogeneity and subpopulations as well as differentially abundant states however modern single-cell RNA sequencing datasets are growing in size and complexity requiring advances in the bioinformatic methods that analyze them. Many methods exist for each step of analysis including read alignment, normalization, quality control, batch effect correction, imputation and dimensionality reduction. With so many options to choose from at each step of the analysis, benchmarking and a synthesis of the literature on the methods available is necessary to inform biological researchers on the most optimal workflow for their data. Here, recent key methods of analysis are highlighted with a focus on methods that facilitate identification of cell subpopulations and differentially abundant cell states. With a constantly expanding toolset for each step in single-cell RNA sequencing dataset analysis, biological researchers should stay informed to utilize the most applicable methods for their own analyses.
ARTICLE | doi:10.20944/preprints202208.0217.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: Ruthenium; crystal structures; ferromagnetic coupling; molecular magnetism; single-ion magnet.
Online: 11 August 2022 (11:41:41 CEST)
Two mononuclear Ru(III) complexes of formula trans-[RuCl4(Hgua)(dmso)]·2H2O (1) and trans-[RuCl4(Hgua)(gua)]·3H2O (2) [Hgua = protonated guanine (gua), dmso = dimethyl sulfoxide] have been synthesized and characterized magnetostructurally. Compounds 1 and 2 crystallize in the monoclinic system with space groups P21/n and Pc, respectively. Each Ru(III) ion in 1 and 2 is six-coordinate and bonded to four chloride ions and one (1) or two (2) nitrogen atoms from guanine molecules and one sulfur atom (1) of a dmso solvent molecule, generating quasi regular octahedral geometries in both cases. In their crystal packing, the Ru(III) complexes are self-assembled mainly through an extended network of N-H⋯Cl hydrogen bonds and π⋯Cl type intermolecular interactions, forming novel supramolecular structures based on this paramagnetic 4d metal ion. Variable-temperature dc magnetic susceptibility measurements performed on microcrystalline samples of 1 and 2 show a different magnetic behavior. While 1 is a ferromagnetic compound at low temperature, 2 exhibits a behavior typical of noninteracting mononuclear Ru(III) complexes with S = 1/2. Ac magnetic susceptibility measurements reveal slow relaxation of the magnetization in the presence of external dc fields only for 2, hence indicating the occurrence of field-induced single-ion magnet (SIM) phenomenon in this mononuclear guanine-based Ru(III) complex.
ARTICLE | doi:10.20944/preprints202202.0312.v1
Subject: Engineering, Civil Engineering Keywords: Geopolymer; Graphene oxide; Single fiber pullout; Bond-slip; Rate sensitive
Online: 24 February 2022 (10:46:46 CET)
In this study, the influence of graphene oxide nanoparticles on the bond-slip behavior of fiber and fly ash based geopolymer paste was examined. Geopolymer paste incorporating graphene oxide nanoparticles solution was cast in half briquetted specimens and embedded with a fiber. Three types of fibers were used: steel, polypropylene, and basalt. The pullout test was performed at two distinct speeds: 1 mm/second and 3 mm/second. Results showed that the addition of graphene oxide increased the compressive strength of geopolymer by about 7%. The bond-slip responses of fibers embedded in geopolymer mixed with graphene oxide exhibited higher peak stress and toughness as compared to those embedded in normal geopolymer. Each fiber type also showed different mode of failure. Both steel and polypropylene fibers showed full bond-slip responses due to their high ductility. Basalt fiber, on the other hand, because of its brittleness, failed by fiber fracture mode which showed no-slip in pull out responses. Both bond strength and toughness were found to be rate sensitive. The sensitivity was higher in graphene oxide/geopolymer than in conventional geopolymer.
REVIEW | doi:10.20944/preprints202202.0004.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Spatial transcriptomics; Molecular imaging; single-cell RNA-seq; intratumoral heterogeneity
Online: 1 February 2022 (11:08:51 CET)
Intratumoral heterogeneity associates with more aggressive disease progression and worse patient outcomes. Understanding the reasons enabling the emergence of such heterogeneity remains incomplete, which restricts our ability to manage it from a therapeutic perspective. Technological advancements such as high-throughput molecular imaging, single-cell omics and spatial transcriptomics now allow recording the patterns of spatiotemporal heterogeneity in a longitudinal manner, thus offering insights into the multi-scale dynamics of its evolution. Here, we review latest technological trends and biological insights from molecular diagnostics as well as spatial transcriptomics, both of which have witnessed a burgeoning growth in recent past in terms of mapping heterogeneity within tumor cell types as well as stromal constitution. We also discuss ongoing challenges, indicating possible ways to integrate insights across these methods to have a systems-level spatiotemporal map of heterogeneity in each tumor, and a more systematic investigation of implications of heterogeneity for the patient outcomes.
ARTICLE | doi:10.20944/preprints202201.0267.v1
Subject: Social Sciences, Psychology Keywords: Gestalt therapy; dementia; depression; single-case experimental design; psychosocial interventions
Online: 19 January 2022 (09:32:12 CET)
Psychotherapy is one of the evidence-based clinical interventions for the treatment of depression in older adults with dementia. Randomized Controlled Trials are often the first methodological choice to gain evidence, yet they are not applicable to a wide range of humanistic psychotherapies. Amongst all, the efficacy of the Gestalt therapy (GT) is under-investigated. The purpose of this paper is to present a research protocol aiming to assess the effects of a GT-based intervention on people with dementia (PWD) and the indirect influence on their family carers. The study implements the Single-Case Experimental Design with Time-Series Analysis that will be carried out in Italy and Mexico. Ten people in each country, who received a diagnosis of dementia and present depressive symptoms, will be recruited. Eight or more GT sessions will be provided whose fidelity will be assessed by the GT Fidelity Scale. Quantitative outcome measures are foreseen for monitoring participants’ depression, anxiety, quality of life, carers’ burden, and the caregiving dyad mutuality, at baseline and follow-up. The advantages and limitations of the research design are considered. If GT will result effective in the treatment of depression in PWD, it could enrich the range of evidence-based interventions provided by healthcare services.