bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementation of the agricultural university educational programs during a pandemic: participants’ opinions
Authors: Filimonyuk Ludmila , Ivashova Valentine , Burlyaeva Victoria , Sorokina Elena , Litvinova Elena
Published: May 2021

The article presents the results of a study of the opinions of students and teachers of the southern region of Russia about the learning process in higher education programs during the COVID-19 pandemic. We carried out a comparative analysis of the quality of the implementation of educational programs in the assessments of participants in the process during the onset of the COVID-19 pandemic (April-May 2020) and its peak values (November-December 2020). The positive and negative consequences of transferring training to a distance learning format are formulated. Among the positive consequences are: the availability of training from anywhere; more flexible training, focused on the educational needs of students; new formats of social student life; more accessible communication with teachers. We analyzed the experience of the educational community presented in publications during the COVID-19 pandemic. The data obtained provide an understanding of the importance of the development and implementation of new organizational and methodological approaches for the effective response of higher education to external global challenges of our time.
Multi-paradigm model of the region’s innovative climate development
Authors: Egorova Alexandra , Uzhegov Artyom
Published: May 2021

The relevance of the innovative development of regional economies is dictated by both an internal factor (balanced development of territories) and an external factor (the country’s competitiveness in the world market). The authors highlight the threats that may arise in different areas of the region’s economic activity. The rating system for assessing the innovation climate in the region has been substantiated and developed. The methodology of the author’s rating assessment of the innovation climate in the region allows a systematic approach to the qualitative and quantitative characteristics of the state of the innovation climate in the region (good, normal, pre-crisis, crisis). On the basis of the developed assessment system, a multi-paradigm model of the formation of an innovation climate in the region is proposed. The proposed author’s model, which reflects the system of factors of the innovation climate in the region, makes it possible to form ways of forming an innovation climate in the context of the selected areas. It seems that the proposed rating system of assessment and the model interconnected with it have applied significance, an integrated approach will allow assessing the level of the innovation climate in the region, and the proposed model will help to develop effective measures to form an innovative climate. The results of the work are the proposed rating system of assessment and a multi-paradigm model interconnected with it. In conclusion, the authors made a number of proposals for the formation of an innovative climate in the region.
Internal control of transactions operation in the sustainable management system of organizations
Authors: Zakirova Alsou , Klychova Guzaliya , Dyatlova Angelina , Ostaev Gamlet , Konina Elena
Published: May 2021

In modern conditions one of the main problems of economic entities is the increase in accounts receivable and payable, which is influenced by objective and subjective factors. In this connection the role of internal control of settlement operations is increasing. The aim of the article is to improve methodological support of internal control of settlement operations for increasing the quality of audit, providing information about the state of settlements with contractors to the management of enterprise for making operational and strategic management decisions. The proposed methodological support is based on stage-by-stage audit of settlement operations including the following main stages: audit planning; implementation of control procedures; execution of audit results. the peculiarity of internal control of settlement operations is determined by a variety of normative and information support of the audit. For the purpose of improvement of control procedures in the course of the study working documents of internal control have been developed. The working document «Verification of the availability of the agreement with a separate counterparty» can be used by the controller to identify errors arising in the preparation of the contract, as well as to determine the completeness and timeliness of the parties to fulfill their obligations, With the proposed in the study working document «Confirmation of the status of settlements with counterparties» can identify cases of fraud and misstatement of data contained in the financial statements. In the course of the study it was proposed to perform a point-rating assessment of debtor reliability based on a system of key indicators in the internal control process. The suggested rating estimation of counterparties will make it possible to carry out their comparative analysis and grouping as well as to identify those counterparties that have a high probability of non-payment of existing debts. The practical significance of the study lies in the possibility of using the developed approaches to determine the information base, to set the purpose and definition of control tasks, to the rational choice of control procedures, to the use of working papers in the process of internal control of settlement operations.
Development of methodological basics of internal control of stocks at the agricultural enterprise
Authors: Zakirova Alsou , Klychova Guzaliya , Tarasova Ludmila , Pimenova Nadezhda , Abasheva Olga Yu.
Published: May 2021

Stocks are one of the key factors that ensure consistency and continuity of reproduction. In this regard, internal control of stocks is an essential element of enterprise management of the enterprise. The aim of the article is to improve the methodological support of internal control of stocks. The article establishes the peculiarities of internal control of availability and safety of stocks in the conditions of development of digital economy. In order to improve control procedures, working documents of internal control of availability and safety of Stocks were developed. In the course of the study, the main stages of internal control over the flow and efficiency of the use of Stocks have been considered. In order to comply with the principles of rationality, priority and consistency in the conduct of internal control, it was proposed to use a working document of internal control «Program for internal control of the movement and efficiency of Stock use». To verify the correctness of the assessment of Stocks during their receipt, procurement, purchase it is proposed to use a working document of internal control «Checking the correctness of the estimate of reserves when they arrive”. This document allows you to identify errors in the evaluation of Stocks, the formation of their actual cost, which affects the cost of production and the final financial result. To increase informativeness and sufficiency of working documents at the analysis of movement of stocks we recommend to use working documents of the internal control containing planned (standard) indicators, similar data of the last periods, indicators on an accrual basis since the beginning of the controlled period. Comparing the controlled indicators with planned values it is possible to estimate their fulfillment and to find out the reasons of discrepancies that can appear as a result of thefts, abuses and violations.
Quantitative fit analysis of acromion fracture plating systems using three-dimensional reconstructed scapula fractures – A multi-observer study
Authors: Charilaou Johan , Dey Roopam , Burger Marilize , Sivarasu Sudesh , van Staden Ruan , Roche Stephen
Published: May 2021

Introduction: Surgical treatment of displaced acromial and scapula spine fractures may be challenging due to the bony anatomy and variable fracture patterns. This difficulty is accentuated by the limitations of the available scapular plates for fracture fixation. This study compares the quantitative fitting of anatomic scapular plates and clavicle plates, using three-dimensional (3D) printed fractured scapulae. Methods: Fourteen scapulae with acromion and spine fractures were used for this study. Computerized tomographic (CT) scans of the fractured scapulae were obtained from the Philips picture archiving and communication system (PACS) database of patients admitted to a tertiary teaching hospital in Cape Town, South Africa between 2012 and 2016. The reconstructed scapulae were 3D printed and the anatomical acromion and clavicle plates were templated about the fracture regions. The fit assessment was performed by five observers who classified the plates as no-fit, intermediate fit, and anatomical fit according to the surgical guidelines. Results: The 6-hole anterior clavicle plate performed better than any of the scapular plates as they were able to fit 45.7% of the fractured acromion, including the spine. Among the pre-contoured anatomical scapula plates, both the short and the long acromion plates could fit only 27.3% of the fractured acromion. The intraclass correlation coefficient was 0.965 suggesting excellent consensus among the five observers. Conclusion: Clavicle plates were found to be better suited to fit around a scapula fracture in its acromion and spine region.
Stationsäquivalente Behandlung – Wie geht das? Umsetzungsstrategien aus acht psychiatrischen Fachkliniken und -abteilungen in Deutschland
Authors: Gottlob Melanie , Holzke Martin , Raschmann Svenja , Bechdolf Andreas , Borbé Raoul , Brieger Peter , Driessen Martin , Horter Hannes , Weinmann Stefan , Längle Gerhard
Published: May 2021

Seit 2018 kann in Deutschland aufsuchende stationsäquivalente Behandlung (StäB) durchgeführt werden. Acht Kliniken der ersten Stunde legen erste Zahlen zu 658 in StäB behandelten Patienten vor. Allgemeine Kennzahlen werden vergleichend, die Details zu Organisationsstruktur, Kooperation, Behandlungsablauf sowie Mitarbeitenden- und Patientenbewertung differenziert nach Standort dargestellt.

Die Ergebnisse zeigen eine hohe Heterogenität der Strukturen und Abläufe bei einer insgesamt sehr positiven Bewertung durch alle Beteiligten. Für gesicherte Schlussfolgerungen reicht die bisherige Datenlage noch nicht aus. Wichtige Hinweise für die weitere Forschung sind aber ableitbar. Entsprechende wissenschaftliche Fragestellungen werden in die AKtiV-Studie des Innovationsfonds eingebracht.
Soziodemografische und störungsbezogene Determinanten zur Inanspruchnahme von ärztlicher oder psychologischer Hilfe bei depressiven Episoden in einem strukturschwachen Flächenland – die besondere Rolle des Lebensalters
Authors: von Eitzen Linnéa , Valerius Karsten , van den Berg Neeltje , Völzke Henry , Grabe Hans J. , Schomerus Georg , Speerforck Sven
Published: May 2021

Ziel der Studie Untersuchung soziodemografischer und störungsbezogener Determinanten zur Inanspruchnahme ärztlicher oder psychologischer Hilfe bei Depressionen im Lebensverlauf.

Methodik In der bevölkerungsbasierten SHIP-Trend-1-Erhebung (2016–2019) wurden N = 490 Personen mit Lebenszeitdiagnosen depressiver Episoden und die Inanspruchnahme professioneller Hilfe erfasst. Geschlecht, sozioökonomischer Status und störungsbezogene Variablen wurden in altersstratifizierten logistischen Regressionsmodellen als Prädiktoren berücksichtigt.

Ergebnisse Männer und Personen im höheren Lebensalter berichteten weniger Inanspruchnahme von Hilfe als Frauen und jüngere Menschen. In unterer und mittlerer Altersgruppe war die Inanspruchnahme mit Störungsschwere assoziiert, in der oberen mit körperlichen Ursachen.

Schlussfolgerung Die Inanspruchnahme professioneller Hilfe war in den verschiedenen Altersgruppen mit unterschiedlichen Prädiktoren assoziiert. Latente Variablen wie altersgruppenspezifische Erfahrungen, Werte und Lebensstile könnten diese Unterschiede erklären.
COVID-19 und psychisches Befinden im zweiten Lockdown – Fortsetzung einer Verlaufsuntersuchung
Authors: Mergel Eduard , Schützwohl Matthias
Published: May 2021

Ziel der Studie Untersuchung zu den Auswirkungen der Corona-Pandemie auf Partizipation, Inklusionserleben und psychisches Befinden bei Personen, die sich mit Blick auf das Vorliegen einer akuten oder chronischen psychischen Störung unterschiedlichen Gruppen zuordnen lassen.

Methodik Follow-up-Erhebung mit Prätest vor Beginn der Corona-Pandemie und 2 Nacherhebungen während bestehender Ausgangsbeschränkungen im April 2020 sowie im November 2020 mittels Fragebogen zur Erfassung von Partizipation und sozialer Inklusion (F-INK) und Brief Symptom Inventory (BSI-18) zur Erfassung subjektiv erlebter psychischer Belastung (n = 112).

Ergebnisse In keiner der untersuchten Gruppen fand sich ein Hinweis dafür, dass es in den ersten 4 Wochen der im November 2020 geltenden Ausgangsbeschränkungen im Vergleich zu den Vorerhebungen zu negativen psychischen Folgen kam.

Schlussfolgerung Das Ergebnis reiht sich in die Studien ein, die fanden, dass die Bevölkerung in den ersten Monaten der Pandemie im Durchschnitt resilient war.
Safety of Cranberry: Evaluation of Evidence of Kidney Stone Formation and Botanical Drug-Interactions
Authors: Madden Emily , McLachlan Caleb , Oketch-Rabah Hellen , Calderón Angela I.
Published: May 2021

Cranberry is a popular ingredient in dietary supplements in the U. S. and is commonly used for preventing urinary tract infections. Because of its popularity in dietary supplements, the U. S. Pharmacopeial Convention has developed quality standards for cranberry ingredients. The purpose of this review was to determine if there are safety issues that should preclude the admission of cranberry ingredients from the development of U. S. Pharmacopeial Convention quality standards. Based on the totality of the data, the U. S. Pharmacopeial Convention concluded that cranberry ingredients are not known to be associated with serious risks to human health when consumed properly in dietary supplements and therefore were admitted for standard development. Although published clinical and animal data indicated that cranberry is not associated with serious adverse effects, interactions with warfarin and kidney stone formation were identified as potential risks. Studies have reported
contradictory data regarding the role of cranberry in kidney stone formation, with some reports suggesting cranberry is associated with a reduced risk of kidney stones. Interactions with warfarin were not associated with moderate intakes of cranberry juice (240 – 480 mL). Some reports suggested that the potential for warfarin interactions requires excessive intakes of cranberry juice (1 – 2 L/day) or cranberry extracts (3000 mg/day). Cases of warfarin interactions with cranberry have mostly involved patients with serious illnesses and/or individuals taking concomitant medications. Based on these findings, the U. S. Pharmacopeial Convention concluded that the use of cautionary labeling statements regarding interactions with warfarin or kidney stone formation is not necessary in the development of quality standards for cranberry ingredients.
Relationship between Verbal and Nonverbal Tests of Auditory Temporal Processing
Authors: Novick Marni , Lucker Jay R.
Published: May 2021

Abstract Background Audiologists may choose to evaluate auditory temporal processing in assessing auditory processing abilities. Some may decide to use measures of nonverbal stimuli such as tonal or noise gap detection. Others may decide to use verbal measures
such as time compressed sentences (TCS). Many may choose to use both. Purpose Since people typically come to audiologists for auditory processing testing complaining of problems processing verbal stimuli, the question arises whether measures of nonverbal stimuli provide evidence
regarding a person's abilities to processing verbal stimuli. That is, are there significant correlations between measures of verbal stimuli and nonverbal stimuli that are used to evaluate auditory temporal processing? Research Design The present investigation is an exploratory
study using file review of 104 people seen for routine auditory processing evaluations by the authors. Study Sample A file review was completed based on data from 104 people seen for auditory processing evaluations. Data Collection and Analyses The data from
these 104 files were used to evaluate whether there are any correlations between verbal and nonverbal measures of auditory temporal processing. The verbal measure used was the TCS subtest of the SCAN-3 while the nonverbal measures included the gap detection screening from the SCAN-3 as well
as the gaps-in-noise measures. Results from these tests were compared to determine whether any significant correlations were found based on results from Pearson product moment correlational analyses. Results None of the nonverbal measures were found to have a significant correlation
with the TCS test findings based on the Pearson correlations used to analyze the data. Conclusion Results indicate that there are no significant correlations (relationships) between measures of auditory temporal processing using nonverbal stimuli versus verbal stimuli based
on the tests used in the present investigation. These findings lead to a conclusion that tests using nonverbal stimuli are measuring different auditory processes than the measure of verbal stimuli used in the present investigation. Since people typically come complaining about understanding
verbal input, it is concluded that audiologists should use some verbal measure of auditory temporal processing in their auditory processing test battery.
Deleterious and Protective Psychosocial and Stress-Related Factors Predict Risk of Spontaneous Preterm Birth
Authors: Becker Martin , Mayo Jonathan A. , Phogat Nisha K. , Quaintance Cecele C. , Laborde Ana , King Lucy , Gotlib Ian H. , Gaudilliere Brice , Angst Martin S. , Shaw Gary M. , Stevenson David K. , Aghaeepour Nima , Dhabhar Firdaus S.
Published: May 2021

Objectives The aim of the study was to: (1) Identify (early in pregnancy) psychosocial and stress-related factors that predict risk of spontaneous preterm birth (PTB, gestational age <37 weeks); (2) Investigate whether “protective” factors (e.g., happiness/social support) decrease risk; (3) Use the Dhabhar Quick-Assessment Questionnaire for Stress and Psychosocial Factors (DQAQ-SPF) to rapidly quantify harmful or protective factors that predict increased or decreased risk respectively, of PTB.

Study Design This is a prospective cohort study. Relative risk (RR) analyses investigated association between individual factors and PTB. Machine learning-based interdependency analysis (IDPA) identified factor clusters, strength, and direction of association with PTB. A nonlinear model based on support vector machines was built for predicting PTB and identifying factors that most strongly predicted PTB.

Results Higher levels of deleterious factors were associated with increased RR for PTB: General anxiety (RR = 8.9; 95% confidence interval [CI] = 2.0,39.6), pain (RR = 5.7; CI = 1.7,17.0); tiredness/fatigue (RR = 3.7; CI = 1.09,13.5); perceived risk of birth complications (RR = 4; CI = 1.6,10.01); self-rated health current (RR = 2.6; CI = 1.0,6.7) and previous 3 years (RR = 2.9; CI = 1.1,7.7); and divorce (RR = 2.9; CI = 1.1,7.8). Lower levels of protective factors were also associated with increased RR for PTB: low happiness (RR = 9.1; CI = 1.25,71.5); low support from parents/siblings (RR = 3.5; CI = 0.9,12.9), and father-of-baby (RR = 3; CI = 1.1,9.9). These factors were also components of the clusters identified by the IDPA: perceived risk of birth complications (p < 0.05 after FDR correction), and general anxiety, happiness, tiredness/fatigue, self-rated health, social support, pain, and sleep (p < 0.05 without FDR correction). Supervised analysis of all factors, subject to cross-validation, produced a model highly predictive of PTB (AUROC or area under the receiver operating characteristic = 0.73). Model reduction through forward selection revealed that even a small set of factors (including those identified by RR and IDPA) predicted PTB.

Conclusion These findings represent an important step toward identifying key factors, which can be assessed rapidly before/after conception, to predict risk of PTB, and perhaps other adverse pregnancy outcomes. Quantifying these factors, before, or early in pregnancy, could identify women at risk of delivering preterm, pinpoint mechanisms/targets for intervention, and facilitate the development of interventions to prevent PTB.

Key Points
Religious and secular ethics offer complementary strategies to achieve environmental sustainability
Authors: Zagonari Fabio
Published: May 2021

By applying a single dataset (i.e., panel data at a national level) and a single analytical framework (i.e., a dynamic mathematical model), I compared religious (REL) and secular (SEC) ethics in two ways: as feasible strategies (i.e., with realistic parameter values such that a strategy can achieve its goal) and as reliable strategies (i.e., with a tight statistical relationship between a strategy and its goal). In both cases, the goal is to achieve environmental sustainability, but with different precepts and principles applied within different perspectives: global vs. local sustainability, individual feelings vs. social pressures as determinants of pro-environmental behavior, and long-run vs. short-run sustainability.Analyticalresults (feasibility) showed that REL are overall more feasible than SEC and, specifically, REL are more likely to affect the many pro-environmental behaviors required to achieve global sustainability, whereas SEC to affect some pro-environmental behaviors required to achieve local sustainability; REL are more likely to affect pro-environmental behaviors based on individual feelings and social pressures from small communities, whereas SEC to affect pro-environmental behaviors based on social pressures from large communities; REL are more likely to solve collective-action problems to achieve short-run sustainability, whereas SEC to solve collective-action problems to achieve long-run sustainability.Statisticalresults (reliability) based on 32 random- and between-effects regressions support these results and, particularly, REL and SEC were complementary in time (e.g., for REL, short-run sustainability is more reliable than long-run sustainability; for SEC, long-run sustainability is more reliable than short-run sustainability), in space (e.g., for SEC, local sustainability is more reliable than global sustainability), and in society (e.g., for REL, individual feelings are more reliable than social pressures).
Generalized symmetry superalgebras
Authors: Açık Özgür , Ertem Ümit
Published: May 2021

We generalize the symmetry superalgebras of isometries and geometric Killing spinors on a manifold to include all the hidden symmetries of the manifold generated by Killing spinors in all dimensions. We show that bilinears of geometric Killing spinors produce special Killing–Yano forms and special conformal Killing–Yano forms. After defining the Lie algebra structure of hidden symmetries generated by Killing spinors, we construct symmetry operators as the generalizations of the Lie derivative on spinor fields. All these constructions together constitute the structure of generalized symmetry superalgebras. We exemplify the construction on weak G2 and nearly Kähler manifolds.
The hopping mechanism of the hydrated excess proton and its contribution to proton diffusion in water
Authors: Arntsen Christopher , Chen Chen , Calio Paul B. , Li Chenghan , Voth Gregory A.
Published: May 2021

In this work, a series of analyses are performed on ab initio molecular dynamics simulations of a hydrated excess proton in water to quantify the relative occurrence of concerted hopping events and “rattling” events and thus to further elucidate the hopping mechanism of proton transport in water. Contrary to results reported in certain earlier papers, the new analysis finds that concerted hopping events do occur in all simulations but that the majority of events are the product of proton rattling, where the excess proton will rattle between two or more waters. The results are consistent with the proposed “special-pair dance” model of the hydrated excess proton wherein the acceptor water molecule for the proton transfer will quickly change (resonate between three equivalent special pairs) until a decisive proton hop occurs. To remove the misleading effect of simple rattling, a filter was applied to the trajectory such that hopping events that were followed by back hops to the original water are not counted. A steep reduction in the number of multiple hopping events is found when the filter is applied, suggesting that many multiple hopping events that occur in the unfiltered trajectory are largely the product of rattling, contrary to prior suggestions. Comparing the continuous correlation function of the filtered and unfiltered trajectories, we find agreement with experimental values for the proton hopping time and Eigen–Zundel interconversion time, respectively.
Phase-resolved electrical detection of coherently coupled magnonic devices
Authors: Li Yi , Zhao Chenbo , Amin Vivek P. , Zhang Zhizhi , Vogel Michael , Xiong Yuzan , Sklenar Joseph , Divan Ralu , Pearson John , Stiles Mark D. , Zhang Wei , Hoffmann Axel , Novosad Valentyn
Published: May 2021

We demonstrate the electrical detection of magnon–magnon hybrid dynamics in yttrium iron garnet/Permalloy (YIG/Py) thin film bilayer devices. Direct microwave current injection through the conductive Py layer excites the hybrid dynamics consisting of the uniform mode of Py and the first standing spin wave (n = 1) mode of YIG, which are coupled via interfacial exchange. Both the two hybrid modes, with Py- or YIG-dominated excitations, can be detected via the spin rectification signals from the conductive Py layer, providing phase resolution of the coupled dynamics. The phase characterization is also applied to a nonlocally excited Py device, revealing the additional phase shift due to the perpendicular Oersted field. Our results provide a device platform for exploring hybrid magnonic dynamics and probing their phases, which are crucial for implementing coherent information processing with magnon excitations.
A general form of Macheret–Fridman classical impulsive dissociation model for nonequilibrium flows
Authors: Adhikari N. , Alexeenko A. A.
Published: May 2021

The rate of dissociation behind a strong shock in thermochemical nonequilibrium depends on the vibrational excitation of the molecules, hence the rates become a function of translational-rotational and vibrational temperatures. The Macheret–Fridman (MF) model provides analytical expressions for nonequilibrium dissociation rates assuming the collision of molecules to be in the impulsive limit. However, the original form of the model was limited to the dissociation of homonuclear molecules. In this work, we present a general form of the Macheret–Fridman classical impulsive model by considering the dissociation of a heteronuclear molecule and present macroscopic rates applicable for modeling dissociation in computational fluid dynamics (CFD). The nonequilibrium dissociation rates from the MF-CFD model compared well with the available quasiclassical trajectory (QCT) data for some important reactions in the air. Additionally, we also present a comparison of the average vibrational energy removed in a dissociation reaction predicted by the MF-CFD model with QCT data for several reactions in air and propose some improvements to the model. The developed MF-CFD model was used to investigate various nonequilibrium flow problems and the results were compared with available experimental data. In general, the results from the MF-CFD model are promising and the model shows a possibility of becoming the standard tool for investigating nonequilibrium flows in CFD.
Revealing the nature of electron correlation in transition metal complexes with symmetry breaking and chemical intuition
Authors: Shee James , Loipersberger Matthias , Hait Diptarka , Lee Joonho , Head-Gordon Martin
Published: May 2021

In this work, we provide a nuanced view of electron correlation in the context of transition metal complexes, reconciling computational characterization via spin and spatial symmetry breaking in single-reference methods with qualitative concepts from ligand-field and molecular orbital theories. These insights provide the tools to reliably diagnose the multi-reference character, and our analysis reveals that while strong (i.e., static) correlation can be found in linear molecules (e.g., diatomics) and weakly bound and antiferromagnetically coupled (monometal-noninnocent ligand or multi-metal) complexes, it is rarely found in the ground-states of mono-transition-metal complexes. This leads to a picture of static correlation that is no more complex for transition metals than it is, e.g., for organic biradicaloids. In contrast, the ability of organometallic species to form more complex interactions, involving both ligand-to-metal σ-donation and metal-to-ligand π-backdonation, places a larger burden on a theory’s treatment of dynamic correlation. We hypothesize that chemical bonds in which inter-electron pair correlation is non-negligible cannot be adequately described by theories using MP2 correlation energies and indeed find large errors vs experiment for carbonyl-dissociation energies from double-hybrid density functionals. A theory’s description of dynamic correlation (and to a less important extent, delocalization error), which affects relative spin-state energetics and thus spin symmetry breaking, is found to govern the efficacy of its use to diagnose static correlation.
Two-dimensional pattern recognition methods for rapidly recording and interpreting high resolution coherent three-dimensional spectra
Authors: Wells Thresa A. , Kwizera Muhire H. , Chen Sarah M. , Jemal Nihal , Brown Morgan D. , Chen Peter C.
Published: May 2021

High resolution coherent multidimensional spectroscopy has the ability to reduce congestion and automatically sort peaks by species and quantum numbers, even for simple mixtures and molecules that are extensively perturbed. The two-dimensional version is relatively simple to carry out, and the results are easy to interpret, but its ability to deal with severe spectral congestion is limited. Three-dimensional spectroscopy is considerably more complicated and time-consuming than two-dimensional spectroscopy, but it provides the spectral resolution needed for more challenging systems. This paper describes how to design high resolution coherent 3D spectroscopy experiments so that a small number of strategically positioned 2D scans may be used instead of recording all the data required for a 3D plot. This faster and simpler approach uses new pattern recognition methods to interpret the results. Key factors that affect the resulting patterns include the scanning strategy and the four wave mixing process. Optimum four wave mixing (FWM) processes and scanning strategies have been identified, and methods for identifying the FWM process from the observed patterns have been developed. Experiments based on nonparametric FWM processes provide significant pattern recognition and efficiency advantages over those based on parametric processes. Alternative scanning strategies that use synchronous scanning and asynchronous scanning to create new kinds of patterns have also been identified. Rotating the resulting patterns in 3D space leads to an insight into similarities in the patterns produced by different FWM processes.
Piezoelectric P(VDF-TrFE) film inkjet printed on silicon for high-frequency ultrasound applications
Authors: Banquart Aline , Callé Samuel , Levassort Franck , Fritsch Lionel , Ossant Frédéric , Toffessi Siewe Sean , Chevalliot Stéphanie , Capri Arnaud , Grégoire Jean-Marc
Published: May 2021

We investigated the innovative processing of poly(vinylidene fluoride-trifluoroethylene) P(VDFx-TrFE1-x) (x = 83 mol. %) by inkjet printing to deliver uniform and thickness-controlled layers on silicon substrates. Here, we provide detailed processing steps and optimize film deposition conditions. The thickness coupling factor for a P(VDF-TrFE) film around 11 μm thick was 22%, demonstrating good electromechanical performance after poling. These multilayer structures were specifically for high-frequency, single-element ultrasonic transducer applications. The measurements of electro-acoustic responses were in water. The maximal frequency was centered at 33.2 MHz and had a fine axial resolution at 22 μm, corresponding to a fractional bandwidth at −6 dB of 100%. In the context of technological evolutions aimed at miniaturized devices and integrated electronics, these results allow for the consideration of complex structures such as multi-element transducers for high-frequency imaging applications.
How accurate is the determination of equilibrium structures for van der Waals complexes? The dimer N2O⋯CO as an example
Authors: Demaison Jean , Vogt Natalja , Jin Yan , Saragi Rizalina Tama , Juanes Marcos , Lesarri Alberto
Published: May 2021

Plausible methods for accurate determination of equilibrium structures of intermolecular clusters have been assessed for the van der Waals dimer N2O⋯CO. In order to assure a large initial dataset of rotational parameters, we first measured the microwave spectra of the 15N2O⋯12CO and 15N2O⋯13CO isotopologs, expanding previous measurements. Then, an anharmonic force field was calculated ab initio and a semi-experimental equilibrium structure was determined. The dimer structure was also calculated at the coupled-cluster level of theory using very large basis sets with diffuse functions and counterpoise correction. It was found that the contributions of the diffuse functions and the counterpoise correction are not additive and do not compensate each other although they have almost the same value but opposite signs. The semi-experimental and ab initio structures were found to be in fair agreement, with the equilibrium distance between the centers of mass of both monomers being 3.825(13) Å and the intermolecular bond length r(C⋯O) = 3.300(9) Å. In this case, the mass-dependent method did not permit us to determine reliable intermolecular parameters. The combination of experimental rotational constants and results of ab initio calculations thus proves to be very sensitive to examine the accuracy of structural determinations in intermolecular clusters, offering insight into other aggregates.
Nonlinear flexural-gravity waves due to a body submerged in the uniform stream
Authors: Semenov Y. A.
Published: May 2021

The two-dimensional nonlinear problem of steady flow past a body submerged beneath an elastic sheet is considered. The mathematical model is based on the velocity potential theory with fully nonlinear boundary conditions on the fluid boundary and the elastic sheet, which are coupled throughout the numerical procedure. The integral hodograph method is employed to derive the complex velocity potential of the flow which contains the velocity magnitude on the interface in explicit form. The coupled problem has been reduced to a system of nonlinear equations with respect to the unknown magnitude of the velocity on the interface, which is solved using a collocation method. Case studies are undertaken for both subcritical and supercritical flow regimes. Results for interface shape, bending moment, and pressure distribution are presented for the wide ranges of Froude numbers and depths of submergence. According to the dispersion equation, two waves on the interface may exist. The first longest wave is that caused by gravity, and the second shorter wave is that caused by the elastic sheet. The obtained solution exhibits a strongly nonlinear interaction of these waves above the submerged body. It is found that near the critical Froude number, there is a range of submergences in which the solution does not converge.
Droplet impact dynamics and heat transfer on nanostructured doubly reentrant cavity under freezing temperature
Authors: Liao Dong , Yang Yinchuang , Qiu Huihe
Published: May 2021

Icephobic materials have wide applications for economic reasons as well as for risk reduction of ice accretion on an airframe. However, the mechanism behind the effect of structure parameters on droplet wetting dynamics and heat transfer on a doubly reentrant cavity is still elusive. This paper reports droplet impact dynamics and heat transfer on a set of doubly reentrant cavity surfaces by changing linewidth, microstructure height, and solid fraction under different surface temperatures and droplet impact velocities. It was found that the ratio of pitch distance and microstructure height is the most important parameter to control droplet dynamics and heat transfer. The surface with a small ratio (P/H < 1) of pitch distance (P) and microstructure height (H) has the best performance, which can successfully repel the droplet even when We = 1000 under −20 °C. The process of the liquid penetration was theoretically studied, and it was found that the temperature of the air inside largely increased due to droplet impact. The smaller the ratio, the higher the temperature increased. The increased air temperature restrains the ice nucleation rate and reduces the viscosity of water to make it easier to be drained out and therefore achieve icephobicity. When the kinetic energy of droplets is sufficient high, the compressed air temperature is so high that an expanding bubble will be generated at the center to make the liquid depart from the surface in a significantly shorter time named “doubly recoil” state, for the liquid in this state is recoiled from both inside and outside.
Fractional-calculus analysis of the transmission dynamics of the dengue infection
Authors: Srivastava H. M. , Jan Rashid , Jan Asif , Deebani Wejdan , Shutaywi Meshal
Published: May 2021

In this research paper, a novel approach in dengue modeling with the asymptomatic carrier and reinfection via the fractional derivative is suggested to deeply interrogate the comprehensive transmission phenomena of dengue infection. The proposed system of dengue infection is represented in the Liouville–Caputo fractional framework and investigated for basic properties, that is, uniqueness, positivity, and boundedness of the solution. We used the next-generation technique in order to determine the basic reproduction number R0 for the suggested model of dengue infection; moreover, we conduct a sensitivity test of R0 through a partial rank correlation coefficient technique to know the contribution of input factors on the output of R0. We have shown that the infection-free equilibrium of dengue dynamics is globally asymptomatically stable for R0<1 and unstable in other circumstances. The system of dengue infection is then structured in the Atangana–Baleanu framework to represent the dynamics of dengue with the non-singular and non-local kernel. The existence and uniqueness of the solution of the Atangana–Baleanu fractional system are interrogated through fixed-point theory. Finally, we present a novel numerical technique for the solution of our fractional-order system in the Atangana–Baleanu framework. We obtain numerical results for different values of fractional-order ϑ and input factors to highlight the consequences of fractional-order ϑ and input parameters on the system. On the basis of our analysis, we predict the most critical parameters in the system for the elimination of dengue infection.
Long-time instability and transient behavior of pressure-driven flow of a power-law fluid in a plane channel overlying a porous layer
Authors: Sengupta Sourav , De Sirshendu
Published: May 2021

The present study is undertaken to analyze the hydrodynamic stability of pressure-driven flow of non-Newtonian fluid-porous systems, where the fluid exhibits the power-law rheology. Such combined fluid-porous flow systems are widely prevalent in diverse geophysical and industrial applications. In the beginning, modal analysis has been performed for comprehending the long-time flow transition characteristics. The plots of the eigenfunctions corresponding to the critical eigenmodes demonstrate the intricate interplay between the non-Newtonian viscosity (quantified by the flow behavior index n) and the porous layer (quantified by depth ratio). It is observed that for a shear-thinning fluid, the flow transition is less sensitive to a variation in depth ratio than that for a shear-thickening fluid. In addition, by exploring the transient energy growth and pseudospectrum in the framework of non-modal stability analysis, the responses to initial conditions and external excitations have been investigated in detail.
Size matters: Effects of the size of heterogeneity on the wave re-entry and spiral wave formation in an excitable media
Authors: Rajagopal Karthikeyan , He Shaobo , Karthikeyan Anitha , Duraisamy Prakash
Published: May 2021

Network performance of neurons plays a vital role in determining the behavior of many physiological systems. In this paper, we discuss the wave propagation phenomenon in a network of neurons considering obstacles in the network. Numerous studies have shown the disastrous effects caused by the heterogeneity induced by the obstacles, but these studies have been mainly discussing the orientation effects. Hence, we are interested in investigating the effects of both the size and orientation of the obstacles in the wave re-entry and spiral wave formation in the network. For this analysis, we have considered two types of neuron models and a pancreatic beta cell model. In the first neuron model, we use the well-known differential equation-based neuron models, and in the second type, we used the hybrid neuron models with the resetting phenomenon. We have shown that the size of the obstacle decides the spiral wave formation in the network and horizontally placed obstacles will have a lesser impact on the wave re-entry than the vertically placed obstacles.
On the voltage–current optimization in high-harmonic gyrotrons
Authors: Novak E. M. , Savilov A. V.
Published: May 2021

In low-power short-wavelength gyrotrons with weak intensity of the electron–wave interaction, determining of the optimal parameters of the system is a result of a trade-off between the enhancement of the electron efficiency and the increase in the Ohmic loss share with an increasing cavity length. In this paper, we investigate the question of whether it is more advantageous to use operating regimes with a higher current at a fixed electron beam power, or whether it is better to increase the accelerating voltage. The answer to the question is determined strictly by the number of the operating cyclotron harmonic of the gyrotron.
A Dirac-semimetal two-dimensional BeN4: Thickness-dependent electronic and optical properties
Authors: Bafekry A. , Stampfl C. , Faraji M. , Yagmurcukardes M. , Fadlallah M. M. , Jappor H. R. , Ghergherehchi M. , Feghhi S. A. H.
Published: May 2021

Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Σ point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic.
Ill-posedness of reconstruction of stress corrosion cracking and a regularization method using multifrequency eddy current signals
Authors: Wang Li
Published: May 2021

Stress corrosion cracking (SCC) widely occurs in the key structures of large-scale mechanical systems and may cause catastrophic accidents without evident macroscopic deformation. A sufficiently accurate quantitative evaluation of SCC is important to guarantee the safety and efficient operation of large mechanical systems. However, the reconstruction accuracy of SCC shape parameters using eddy current testing (ECT) signals remains a problem, given the complex microstructure of cracks and the properties of the ECT inverse problem. In this study, a two-dimensional numerical model of crack with conductivity distribution is used to calculate the ECT signals due to SCC. The relation between crack parameters and ECT signals is investigated through simulation and experiment. Results show that the ill-posedness of SCC shape reconstruction is mainly manifested in the nonuniqueness of the solution of crack shape parameters. Therefore, a regularization method based on the features of multifrequency ECT signals is proposed to solve ill-posedness by adding prior information to the solution space of the optimization problem. The reconstruction results of the simulated and measured ECT signals from the conductive crack models verify that the proposed strategy can effectively improve the precision of SCC shape reconstruction.
Microevolution in the pansecondary metabolome of
Aspergillus flavus
and its potential macroevolutionary implications for filamentous fungi
Authors: Drott Milton T. , Rush Tomás A. , Satterlee Tatum R. , Giannone Richard J. , Abraham Paul E. , Greco Claudio , Venkatesh Nandhitha , Skerker Jeffrey M. , Glass N. Louise , Labbé Jesse L. , Milgroom Michael G. , Keller Nancy P.
Published: May 2021

Significance

Secondary metabolites (SMs) produced by fungi mediate ecological interactions, define fungal niches, and are of profound pharmacological importance to humans. Most work on SMs has focused on a small number of individuals from each species, not fully reflecting the importance of intraspecific diversity. We demonstrate that even in one of the best-studied model fungi, the carcinogen-producing
Aspergillus flavus
, more than 25% of SM-producing biosynthetic gene clusters (BGCs) are novel and/or show population-specific variants. These results support the finding that the organization of BGC diversity into population-specific patterns may sometimes result from ecologically important interactions and may inform evolutionary and etiological inferences of SM capacities within a species. Importantly, our work also presents a vision of sources of potential pharmaceuticals.
Sequential dynein effectors regulate axonal autophagosome motility in a maturation-dependent pathway
Authors: Cason Sydney E. , Carman Peter J. , Van Duyne Claire , Goldsmith Juliet , Dominguez Roberto , Holzbaur Erika L.F.
Published: May 2021

Autophagy is a degradative pathway required to maintain homeostasis. Neuronal autophagosomes form constitutively at the axon terminal and mature via lysosomal fusion during dynein-mediated transport to the soma. How the dynein–autophagosome interaction is regulated is unknown. Here, we identify multiple dynein effectors on autophagosomes as they transit along the axons of primary neurons. In the distal axon, JIP1 initiates autophagosomal transport. Autophagosomes in the mid-axon require HAP1 and Huntingtin. We find that HAP1 is a dynein activator, binding the dynein–dynactin complex via canonical and noncanonical interactions. JIP3 is on most axonal autophagosomes, but specifically regulates the transport of mature autolysosomes. Inhibiting autophagosomal transport disrupts maturation, and inhibiting autophagosomal maturation perturbs the association and function of dynein effectors; thus, maturation and transport are tightly linked. These results reveal a novel maturation-based dynein effector handoff on neuronal autophagosomes that is key to motility, cargo degradation, and the maintenance of axonal health.