bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrodynamic stress and phenotypic plasticity of the zebrafish regenerating fin
Authors: Dagenais Paule , Blanchoud Simon , Pury David , Pfefferli Catherine , Aegerter-Wilmsen Tinri , Aegerter Christof M. , Jaźwińska Anna
Published: June 2021

Understanding how extrinsic factors modulate genetically encoded information to produce a specific phenotype is of prime scientific interest. In particular, the feedback mechanism between abiotic forces and locomotory organs during morphogenesis to achieve efficient movement is a highly relevant example of such modulation. The study of this developmental process can provide unique insights on the transduction of cues at the interface between physics and biology. Here, we take advantage of the natural ability of adult zebrafish to regenerate their amputated fins to assess its morphogenic plasticity upon external modulations. Using a variety of surgical and chemical treatments, we could induce phenotypic responses to the structure of the fin. Through the ablation of specific rays in regenerating caudal fins, we generated artificially narrowed appendages in which the fin cleft depth and the positioning of rays bifurcations were perturbed compared with normal regenerates. To dissect the role of mechanotransduction in this process, we investigated the patterns of hydrodynamic forces acting on the surface of a zebrafish fin during regeneration by using particle tracking velocimetry on a range of biomimetic hydrofoils. This experimental approach enabled us to quantitatively compare hydrodynamic stress distributions over flapping fins of varying sizes and shapes. As a result, viscous shear stress acting on the distal margin of regenerating fins and the resulting internal tension are proposed as suitable signals for guiding the regulation of ray growth dynamics and branching pattern. Our findings suggest that mechanical forces are involved in the fine-tuning of the locomotory organ during fin morphogenesis.
Rare diseases in the practice of a rheumatologist: a long way to diagnosis
Authors: Belyaeva Elena
Published: June 2021

Diagnosis of rare diseases in clinical practice can cause difficulties due to insufficient awareness of doctors. The article presents clinical observations of patients with Behcet's disease, recurrent polychondritis, and Macla-Wales syndrome.
Problems of cardiovascular comorbidity in patients with osteoarthritis
Authors: Vol'nyagina A. , Belyaeva Elena
Published: June 2021

Osteoarthritis (OA) is the most common joint disease with high comorbidity. Among comorbid diseases in patients with OA, diseases of the cardiovascular system are in the first place. It is known that comorbid diseases mutually aggravate the course of each of the existing nosologies.It is important to study the impact of concomitant diseases in patients with OA on the quality and duration of life, to analyze the factors that contribute to an increased risk of cardiovascular disasters in patients with degenerative and destructive joint diseases.
¿Es hora de un cambio de ministro? La supervivencia del gabinete en Colombia 1958-2018
Authors: Mejía Luis Bernardo , Barinas Forero Andrés Felipe , Mora Oviedo Michelle Lorena
Published: June 2021

Este artículo analiza la formación y supervivencia de los gabinetes presidenciales en Colombia entre 1958 y 2018. Se comparan dos períodos de la historia política del país. Durante el primer período, de 1958 a 1990, Colombia funcionó con un sistema bipartidista. El segundo período, de 1991 a la actualidad, se caracteriza por la aper­tura del régimen político a nuevos partidos y la formación de gobiernos de coalición. Para esto, utilizamos modelos semiparamétricos y regresiones de Cox que nos permiten estimar la supervivencia de 581 nombramientos ministeriales e identificar los predictores de supervivencia en sus cargos a partir tanto de las características individuales de los ministros como de las características institucionales del sistema. El estudio muestra que la estabilidad en los cargos de los ministros durante el periodo bipartidista es menor que la duración de los ministros durante la etapa de presidencialismos de coalición.
Toward a Substantive Theory of the Academic Advising Process: A Grounded Theory
Authors: McGill Craig M.
Published: June 2021

The role of academic advising in higher education remains largely misunderstood by university stakeholders, faculty and staff, students, and academic advisors. Many hold the simplistic view that academic advising is merely transmitting information to students to ensure timely graduation, a perception that limits what advising can do for student learning, growth, and development. Interviews with NACADA leaders and document analysis reveals a grounded theory of the academic advising process: within the advising context, students connect with caring institutional representatives, make meaning of experiences, and engage in informed decision-making. Synthesizing these experiences helps students develop their academic identity. The theory can aid stakeholders outside of academic advising and give practicing advisors language to explain the valuable work they do with students.
Latinx Community College Students on Academic Probation: Struggles and Success
Authors: McPherson Maria Paula , Arbelo Marrero Floralba
Published: June 2021

Latinx undergraduate students on academic probation after their first semester of community college risk further course failure and dropping out. As the largest minority on college campuses, it is important to understand Latinx college students' experiences with academic probation during freshman year to develop strategies that can support them in the community college context. Using Schlossberg's and Tinto's transition theories, we explored nine Latinx community college students' perceptions after being placed on academic probation during freshman year. Findings indicate that challenges managing employment, coursework, family obligations, and academic and social integration, as well as difficulties navigating the college system, contributed to academic probationary status. Furthermore, these participants developed significant emotional stress, transformational experiences, and new behaviors due to academic probation.
Revisiting the Role of Academic Advising in Equitably Serving Diverse College Students
Authors: Museus Samuel D.
Published: June 2021

It has been more than a decade since Museus and Ravello analyzed the roles that culturally engaging academic advisors play in producing equitable outcomes among racially diverse student populations. Their study highlighted the importance of humanized, holistic, and proactive advising in effectively serving students of color in particular. In this essay, one of the original authors discusses how a decade of research has built on this earlier analysis and summarizes evolving insights about the role of culturally engaging advising in supporting students of color. The article concludes with implications for future research, policy, and practice aimed at more equitably serving diverse populations.
Um esqueleto num cavalo branco
Authors: Belisario da Silva Raquel
Published: June 2021

O presente artigo propõe analisar a peça A doença branca, do escritor tcheco Karel Čapek, publicada e encenada pela primeira vez no ano de 1937. Será considerada a situação política europeia naquele período, bem como o reflexo, dentro da obra, do pensamento e das opiniões do autor sobre tal situação. Como aporte teórico, o texto trará a contribuição de Susan Sontag, que se dedicou a escrever sobre a doença enquanto metáfora, inclusive na literatura. Além disso, estudos dedicados à vida e à obra de Čapek comporão um quadro mais geral sobre o qual se poderá apoiar a apreciação desse drama específico. Busca-se, com isso, partir do exame do drama selecionado, e de como o autor aborda o tema da doença, para pensar a atualidade dessa leitura no momento em que o mundo, uma vez mais, é atingido por uma pandemia.
Prostituição, neoconservadorismo e pandemia – o Movimento de Prostitutas e os desafios da Covid-19
Authors: Rodrigues Marlene Teixeira
Published: June 2021

Este texto analisa o acesso à direitos de pessoas que exercem a prostituição, no contexto da pandemia e tendo em conta, o avanço da extrema direita e do neoconservadorismo no Brasil e suas repercussões na esfera da ação estatal. O avanço conservador – que se delineou antes da eleição de Bolsonaro e da pandemia, ganhou contornos dramáticos com a chegada da Covid-19. A análise das iniciativas realizadas por organizações do Movimento de Prostitutas, no período da pandemia, identificadas mediante pesquisa documental, revela os desafios, a agenda e as estratégias adotadas pelo Movimento, diante do desmonte e desfinanciamento das ações governamentais, patrocinado pelo novo governo. A se destacar a construção de articulações com diferentes sujeitos políticos, de diferentes esferas, a fim de fazer frente às demandas (novas e velhas) agudizadas pela pandemia e à ausência de apoio do governo federal. Palavras-Chave: Prostituição. Neoconservadorismo. Trabalho Sexual. Covid-19
Appearance and infrastructure of cities of modern Luhansk region in the XIX – early XX centuries according to statistical sources
Authors:   State Institution Luhansk Taras Shevchenko National University, Zabudkova Olha
Published: June 2021

The article, based on statistical materials collected and published by the official bodies of the Russian Empire, analyzes the appearance and infrastructure of cities in the modern Luhansk region during the XIX – early XX centuries. The main attention is paid to the cities that had official status – Starobilsk, Slavyanoserbsk, Luhansk. At the same time, the statistics included the largest rural settlements (Bilovodsk, Svatova Luchka, etc.), information about which is also taken into account. Quantitative characteristics of urban development (building materials, paving and street lighting, etc.) are studied. The issues of introduction of technical innovations in cities – telegraph, telephone, water supply, removal of household waste, as well as the state of public transport – were considered separately. Another indicator under consideration is the provision of infrastructure to fulfill the social function of cities - the situation of educational and medical affairs, firefighting, police and others. It was found that in the second half of the XIX century. New establishments of trade and public catering developed rapidly, which was connected with the strengthening of the trade function not only of the official cities, but also of some settlements (Bilovodsk, Svatova Luchka). Quantitative indicators of infrastructure development in the cultural sphere are considered separately. It is concluded that the development of a specific urban environment in the modern Luhansk region in the XIX – early XX centuries. took place in the stream of general trends, but on a smaller scale. A certain exception was Luhansk, whose pace of modernization was the highest.
Mongolian international order in the middle of the XIII century according to the testimony of the papal legate Giovanni del Plano Carpini
Authors:   State Institution Luhansk Taras Shevchenko National University, Koval Alina
Published: June 2021

The article considers the process of formation and development of the medieval international order during the end of the active phase of the Mongol conquests in Eastern and Western Europe in the middle of the thirteenth century. The main source in the study of this issue was the evidence set out in the treatise "History of the Mongols, called by us Tatars" by the famous Catholic diplomat Plano Carpini, who in the 40's of the thirteenth century by order of Pope Innocent IV, he carried out a mission to the Mongol Empire.The article notes that this aspect is one of the least studied in modern Ukrainian historiographyAs a result of the study, the author came to the conclusion that the work analyzed in the article is an important source in the study of the international order, which developed in the middle of the thirteenth century and was based on the dominance of the Mongol Empire in Eurasia. It allows us to consider the peculiarities of the organization of this state, to show the characteristics of its relations with the captured peoples, to determine the order of relations between the Mongols and their vassals. At the same time, this treatise is a manifesto in which, under the pretext of the Mongol threat, it is concluded that it is necessary to unite the rulers of Europe (especially its Orthodox part) under the authority of the Pope. Consideration of the ideas set forth by Carpini, allows us to conclude that the Catholic Church, and in this period, tried to implement the project of its religious expansion in the lands of Eastern Europe and Kiyvan Rus.
Using the alternative history method in the study of World War II
Authors:   Bogdan Khmelnitsky Melitopol State Pedagogical University, Zhiryakov Olexandr , Pachev Serhii ,   Bogdan Khmelnitsky Melitopol State Pedagogical University
Published: June 2021

The article discusses the scientific experience of using the „alternative history” method in the study of the history of the Second World War. The authors revealed the peculiarities of the methodology for applying this method in world historical science until the middle of the twentieth century, showed its research capabilities and shortcomings. The features of the use of the method of alternative history in the modern historiography of the Second World War are revealed. The purpose of this article is to compare the main methodological approaches to the application of the method of „alternative history” in the historiography of World War II, to determine the degree of their appropriateness and correctness. To achieve this goal, the following tasks are set: to consider the genesis of the method of „alternative history”, to establish and reveal its key provisions, the algorithm of use, application and features of use in British and Russian historiography. At the present stage, the method of alternative history makes it possible to significantly expand the cognitive possibilities in the study of the history of the Second World War. Its use was pioneered by representatives of Anglo-American historiography. In the post-Soviet space, this method was established much later.
Libraries and their activities in the context of historical and local history development in the region
Authors:   Odessa National University of Economics, Shcherbyna Nadiia
Published: June 2021

The article reveals the historical and local history activities of the libraries of the Odessa region in the second half of the 40s – 80s XX century. The analysis of this activity indicates that despite the great difficulties (the residual principle of financing culture, and the weak material and technical base of libraries), they have become real centers of local history work in the region. During this period, libraries have accumulated a significant bibliographic base on local history issues, acquired extensive experience in working with local history research. In the development of library local lore, an important role was played by bibliographers of local lore of Odessa scientific libraries. Thanks to their activities, a local history fund was collected in almost every library, catalogs and card indexes were created, which included numerous materials on various local history topics. That is why libraries performed the social functions of education and culture units and became centers of local history. However, the regional studies of the regional libraries require further in-depth study, because by that time they, acting as regional information centers, were engaged in the search, storage and provision of local history literature for public use. The development of library local lore in the region was negatively affected by those general tendencies of social life arising from the very nature of the then totalitarian regime.
South Caucasus in the plans of the warring parties on the eve of the Crimean War (1853–1856)
Authors:   State Institution Luhansk Taras Shevchenko National University, Buryan Mykhailo , Buryan Mariia ,   State Institution Luhansk Taras Shevchenko National University
Published: June 2021

This article deals with topical issues related to the analysis of the international situation that developed on the European continent, in the South Caucasus, in Asia Minor on the eve of the Crimean War (1853–1856). Special attention is paid to the geopolitical plans of Great Britain, France, Austria, and the Ottoman Empire in relation to the South Caucasus region, where the Russian Empire was quite strong at that time. As a result of the victorious Russo-Iranian (1804–1813) and Russo-Turkish (1806–1812) Wars, The Russian Empire controlled the territory of almost the entire Caucasus region, which could not but worry London, because this threatened the British presence in India-a colonial Pearl that Great Britain was not going to lose. British analysts warned their government about the danger from the Russian Empire, and the Western press supported them in this. France joined the anti-Russian coalition, pursuing its own goals. London and Paris have made efforts to get Vienna to stand up to Russia as well. As a result of the upcoming war, the countries of the South Caucasus (Georgia, Armenia, Circassian, etc.) were to fall under the Protectorate of Turkey and Great Britain. The author draws attention to the fact that there were several plans to start a war against the Russian Empire, in each of which a significant role was assigned to the Crimean Peninsula, the military-political and strategic importance of which does not lose its weight today, especially against the background of the tense situation in the black and Azov seas in our time.
The peasantry of Donbass during the first war of Soviet Russia against the UPR and the Donetsk-Kryvyi Rih Soviet Republic
Authors:   Novomoskovsk College of the Dnipro State Agrarian and Economic University, Datsenko Artem
Published: June 2021

The article studies the events in the countryside of Donbass since December 1917 to May 1918 The author examines the features of the Bolshevik policy in the Donbass in the countryside and the attitude of the peasants to this policy. The events geographically described in the article cover the territory of Donetsk and Lugansk regions within the boundaries of 2013. The article examines the main directions of the agrarian policy of the Soviet government in the form of redistribution of land and implements, the creation of collective farms, pumping out products from the village, as well as anti-Ukrainian separatism as a tactical step of the Bolsheviks. The author notes the artificiality of such a state formation as the Donetsk-Kryvyi Rih Soviet Republic, as well as the fact that it was invented by the Bolsheviks solely for tactical purposes and did not defend the interests of the overwhelming majority of the Donbass population. The article analyzes the peasant resistance to the policy of „war communis”, as well as the role of the peasantry in countering the counter-offensive of the UPR army, supported by the German and Austro-Hungarian armies. The author comes to the conclusion that the Donbass peasantry did not want to defend the DKSR, which was one of the reasons for the defeat of the Bolsheviks on the territory of Donbass and the future elimination of the Donetsk-Kryvyi Rih Soviet Republic by the Bolsheviks as a state entity.
Frontier: Drainage Water Recycling in the Humid Regions of the U.S.: Challenges and Opportunities
Authors: Hay Christopher H. , Reinhart Benjamin D. , Frankenberger Jane R. , Helmers Matthew J. , Jia Xinhua , Nelson Kelly A. , Youssef Mohamed A.
Published: June 2021

Highlights

Drainage water recycling captures and stores agricultural drainage water for reuse as supplemental irrigation.

Drainage water recycling can both increase crop production and benefit downstream water quality.

Depending on management, drainage water recycling can also provide other complementary benefits.

Research needs to advance drainage water recycling are presented and discussed.

Keywords: Drainage water quality, Drainage water reuse, Subsurface drainage, Supplemental irrigation, Agricultural resiliency.
Effects of Post-Harvest Conditions on Sorption Isotherms of Soybeans
Authors: Diaz-Contreras Lina M , Ramachandran Rani Puthukulangara , Cenkowski Stefan , Paliwal Jitendra
Published: June 2021

Abstract. This study focuses on the modeling of sorption characteristics of three varieties of soybeans (Akras R2, Lono R2, and Podaga R2). Three pretreatments related to post-harvest conditions were tested on the soybean varieties: (1) freshly harvested soybeans, (2) soybeans subjected to three drying and wetting cycles, and (3) soybeans subjected to three freezing and thawing cycles. The adsorption and desorption experiments were conducted at 5°C, 10°C, 15°C, 20°C, 25°C, and 30°C using a dynamic equilibrium relative humidity (ERH) apparatus. Equilibrium moisture content (EMC) and the corresponding ERH were measured. The parameters calculated for the modified Halsey equation are applicable for storage temperatures above 10°C in the relative humidity (RH) ranges of 10% to 80% for desorption and 30% to 80% for adsorption. No significant differences were found in sorption isotherms among the soybean varieties. However, the soybean varieties responded differently to the different pretreatments (i.e., drying/wetting and freezing/thawing cycles). The adsorption isotherms of Akras and Lono soybeans showed significant differences at 10°C to 30°C when subjected to drying and wetting cycles, while Akras and Podaga soybeans showed significant differences in the same temperature range when subjected to freezing and thawing cycles. The effect of drying and wetting cycles on the desorption isotherms was found only for Akras soybeans at 10°C and 15°C below 63% and 71% RH, respectively, and for Lono soybeans at 25°C and 30°C above 69% RH for both temperatures. In general, the effect of both pretreatments on the sorption isotherms of soybeans was a reduction in EMC of up to 20%, when compared to fresh samples at selected storage temperatures. The findings of this study serve as a primary tool for developing a lookup table for safe storage guidelines for soybeans. Keywords: Equilibrium moisture content, Equilibrium relative humidity, Halsey equation, Oswin equation, Soybeans.
Frontier: Discipline-Based Education Research to Advance Authentic Learning in Agricultural and Biological Engineering
Authors: Diefes-Dux Heidi A.
Published: June 2021

Highlights

Discipline-based education research can provide unique insights for agricultural and biological engineering.

Authentic learning has the potential to transform teaching practices and student learning.

Work in the five areas of engineering education research provides a foundation for discipline-specific inquiry.

An agricultural and biological engineering education research agenda is advised.

Keywords: Authentic learning, Discipline-based education research.
Percepción de los factores de transición a la universidad:
incidencia de la realidad plural de los estudiantes
Authors: Freixa-Niella Montserrat , Dorio-Alcaraz Immaculada , Figuera-Gazo Pilar , Torrado-Fonseca Mercedes
Published: June 2021

INTRODUCCIÓN. Este artículo analiza la transición
universitaria, en el primer semestre del primer curso, de los
estudiantes de los grados de Educación Social, Educación Infantil y
Relaciones Laborales de la Universidad de Barcelona. Se centra en
los factores facilitadores e inhibidores de la transición y la
conducta de estudio que muestran los estudiantes con diferentes
trayectorias académicas previas. MÉTODO. Se realiza un estudio
descriptivo por encuesta a partir de un cuestionario (cumplimentado
por 651 estudiantes) sobre las trayectorias académicas previas de
los estudiantes. RESULTADOS. Hay diferencias en las valoraciones de
los estudiantes en función de su titulación y trayectoria de acceso.
Los estudiantes procedentes de vías profesionalizadoras (Ciclos
formativos) encuentran más barreras en su proceso de transición y
puntúan más alto los factores inhibidores. Se resalta el desajuste
académico entre las expectativas iniciales de los estudiantes y el
plan de estudios. Se enfatiza el apoyo del entorno y la relación con
los compañeros como factor facilitador de la transición. DISCUSIÓN.
Los resultados aconsejan repensar las propuestas de orientación y de
acción tutorial hacia modelos holísticos que permitan un contexto
institucional más disponible, más flexible y con una mayor capacidad
de adaptación a la pluralidad emergente de estudiantes.
Backscattering polarimetric imaging of the human brain to determine the orientation and degree of alignment of nerve fiber bundles
Authors: Jain Arushi , Ulrich Leonie , Jaeger Michael , Schucht Philippe , Frenz Martin , Günhan Akarcay H.
Published: June 2021

The nerve fiber bundles constitutive of the white matter in the brain are organized in such a way that they exhibit a certain degree of structural anisotropy and birefringence. The birefringence exhibited by such aligned fibrous tissue is known to be extremely sensitive to small pathological alterations. Indeed, highly aligned anisotropic fibers exhibit higher birefringence than structures with weaker alignment and anisotropy, such as cancerous tissue. In this study, we performed experiments on thick coronal slices of a healthy human brain to explore the possibility of (i) measuring, with a polarimetric microscope the birefringence exhibited by the white matter and (ii) relating the measured birefringence to the fiber orientation and the degree of alignment. This is done by analyzing the spatial distribution of the degree of polarization of the backscattered light and its variation with the polarization state of the probing beam. We demonstrate that polarimetry can be used to reliably distinguish between white and gray matter, which might help to intraoperatively delineate unstructured tumorous tissue and well organized healthy brain tissue. In addition, we show that our technique is able to sensitively reconstruct the local mean nerve fiber orientation in the brain, which can help to guide tumor resections by identifying vital nerve fiber trajectories thereby improving the outcome of the brain surgery.
Prediction of internal modification size in glass induced by ultrafast laser scanning
Authors: Shen Hong , Tian Chenyun , Jiang Zhongping
Published: June 2021

The modification at the interface between glass plates induced by ultrafast laser is important for the glass welding strength, therefore the relationship between the modification size and processing parameters should be identified. The experimental method has its limitation in understanding the nature of the modification. In this study, a numerical model for the temperature distribution determining the modification size induced by ultrafast laser scanning is developed, in which a three-dimensional steady model for the beam propagation with a transient ionization model is established to estimate the free electron density by the single laser pulse, and then a heat accumulation model for multiple laser pulses is employed to describe energy transportation within the irradiated bulk. The experiment for the internal modifications in single-piece fused silica samples irradiated by a picosecond laser with different pulse energies and scanning velocities is performed to validate the present model.
Statistical Mueller matrix driven discrimination of suspended particles
Authors: Li Jiajin , Wang Hongjian , Liao Ran , Wang Yong , Liu Zhidi , Zhuo Zepeng , Guo Zhiming , Ma Hui
Published: June 2021

An effective method to calculate the statistical Mueller matrix (SMM) of suspended particles based on polarized light scattering is presented that takes advantage of the Stokes vectors measurement of individual particles. The calculation method of the SMM is derived based on statistics. Experimental results of Microcystis samples confirm that the SMM can characterize cells of different states. Then, pairwise contrast experiments indicate the great prospect of the SMM applied on the discrimination of suspended particles. It helps to find the optimal incident polarization state to discriminate suspended particles, and it has optimal discrimination ability. The parameter derived from the SMM can simultaneously discriminate particles including microalgae, microplastics, and sand-like particles.
Comprehensive glycoproteomics shines new light on the complexity and extent of glycosylation in archaea
Authors: Schulze Stefan , Pfeiffer Friedhelm , Garcia Benjamin A. , Pohlschroder Mechthild
Published: June 2021

Glycosylation is one of the most complex posttranslational protein modifications. Its importance has been established not only for eukaryotes but also for a variety of prokaryotic cellular processes, such as biofilm formation, motility, and mating. However, comprehensive glycoproteomic analyses are largely missing in prokaryotes. Here, we extend the phenotypic characterization of N-glycosylation pathway mutants in Haloferax volcanii and provide a detailed glycoproteome for this model archaeon through the mass spectrometric analysis of intact glycopeptides. Using in-depth glycoproteomic datasets generated for the wild-type (WT) and mutant strains as well as a reanalysis of datasets within the Archaeal Proteome Project (ArcPP), we identify the largest archaeal glycoproteome described so far. We further show that different N-glycosylation pathways can modify the same glycosites under the same culture conditions. The extent and complexity of the Hfx. volcanii N-glycoproteome revealed here provide new insights into the roles of N-glycosylation in archaeal cell biology.
Estimating the cumulative incidence of COVID-19 in the United States using influenza surveillance, virologic testing, and mortality data: Four complementary approaches
Authors: Lu Fred S. , Nguyen Andre T. , Link Nicholas B. , Molina Mathieu , Davis Jessica T. , Chinazzi Matteo , Xiong Xinyue , Vespignani Alessandro , Lipsitch Marc , Santillana Mauricio
Published: June 2021

Effectively designing and evaluating public health responses to the ongoing COVID-19 pandemic requires accurate estimation of the prevalence of COVID-19 across the United States (US). Equipment shortages and varying testing capabilities have however hindered the usefulness of the official reported positive COVID-19 case counts. We introduce four complementary approaches to estimate the cumulative incidence of symptomatic COVID-19 in each state in the US as well as Puerto Rico and the District of Columbia, using a combination of excess influenza-like illness reports, COVID-19 test statistics, COVID-19 mortality reports, and a spatially structured epidemic model. Instead of relying on the estimate from a single data source or method that may be biased, we provide multiple estimates, each relying on different assumptions and data sources. Across our four approaches emerges the consistent conclusion that on April 4, 2020, the estimated case count was 5 to 50 times higher than the official positive test counts across the different states. Nationally, our estimates of COVID-19 symptomatic cases as of April 4 have a likely range of 2.3 to 4.8 million, with possibly as many as 7.6 million cases, up to 25 times greater than the cumulative confirmed cases of about 311,000. Extending our methods to May 16, 2020, we estimate that cumulative symptomatic incidence ranges from 4.9 to 10.1 million, as opposed to 1.5 million positive test counts. The proposed combination of approaches may prove useful in assessing the burden of COVID-19 during resurgences in the US and other countries with comparable surveillance systems.
Contact tracing efficiency, transmission heterogeneity, and accelerating COVID-19 epidemics
Authors: Gardner Billy J. , Kilpatrick A. Marm
Published: June 2021

Simultaneously controlling COVID-19 epidemics and limiting economic and societal impacts presents a difficult challenge, especially with limited public health budgets. Testing, contact tracing, and isolating/quarantining is a key strategy that has been used to reduce transmission of SARS-CoV-2, the virus that causes COVID-19 and other pathogens. However, manual contact tracing is a time-consuming process and as case numbers increase a smaller fraction of cases’ contacts can be traced, leading to additional virus spread. Delays between symptom onset and being tested (and receiving results), and a low fraction of symptomatic cases being tested and traced can also reduce the impact of contact tracing on transmission. We examined the relationship between increasing cases and delays and the pathogen reproductive number Rt, and the implications for infection dynamics using deterministic and stochastic compartmental models of SARS-CoV-2. We found that Rt increased sigmoidally with the number of cases due to decreasing contact tracing efficacy. This relationship results in accelerating epidemics because Rt initially increases, rather than declines, as infections increase. Shifting contact tracers from locations with high and low case burdens relative to capacity to locations with intermediate case burdens maximizes their impact in reducing Rt (but minimizing total infections may be more complicated). Contact tracing efficacy decreased sharply with increasing delays between symptom onset and tracing and with lower fraction of symptomatic infections being tested. Finally, testing and tracing reductions in Rt can sometimes greatly delay epidemics due to the highly heterogeneous transmission dynamics of SARS-CoV-2. These results demonstrate the importance of having an expandable or mobile team of contact tracers that can be used to control surges in cases. They also highlight the synergistic value of high capacity, easy access testing and rapid turn-around of testing results, and outreach efforts to encourage symptomatic cases to be tested immediately after symptom onset.
Rad21l1 cohesin subunit is dispensable for spermatogenesis but not oogenesis in zebrafish
Authors: Blokhina Yana P. , Frees Michelle A. , Nguyen An , Sharifi Masuda , Chu Daniel B. , Bispo Kristi , Olaya Ivan , Draper Bruce W. , Burgess Sean M.
Published: June 2021

During meiosis I, ring-shaped cohesin complexes play important roles in aiding the proper segregation of homologous chromosomes. RAD21L is a meiosis-specific vertebrate cohesin that is required for spermatogenesis in mice but is dispensable for oogenesis in young animals. The role of this cohesin in other vertebrate models has not been explored. Here, we tested if the zebrafish homolog Rad21l1 is required for meiotic chromosome dynamics during spermatogenesis and oogenesis. We found that Rad21l1 localizes to unsynapsed chromosome axes. It is also found between the axes of the mature tripartite synaptonemal complex (SC) in both sexes. We knocked out rad21l1 and found that nearly all rad21l1-/- mutants develop as fertile males, suggesting that the mutation causes a defect in juvenile oogenesis, since insufficient oocyte production triggers female to male sex reversal in zebrafish. Sex reversal was partially suppressed by mutation of the checkpoint gene tp53, suggesting that the rad21l1 mutation activates Tp53-mediated apoptosis or arrest in females. This response, however, is not linked to a defect in repairing Spo11-induced double-strand breaks since deletion of spo11 does not suppress the sex reversal phenotype. Compared to tp53 single mutant controls, rad21l1-/- tp53-/- double mutant females produce poor quality eggs that often die or develop into malformed embryos. Overall, these results indicate that the absence of rad21l1-/- females is due to a checkpoint-mediated response and highlight a role for a meiotic-specific cohesin subunit in oogenesis but not spermatogenesis.
Sodium alginate microencapsulation improves the short-term oral bioavailability of cannabidiol when administered with deoxycholic acid
Authors: Majimbi Maimuna , Brook Emily , Galettis Peter , Eden Edward , Al-Salami Hani , Mooranian Armin , Al-Sallami Hesham , Lam Virginie , Mamo John C. L. , Takechi Ryusuke
Published: June 2021

Background

Cannabidiol (CBD) confers therapeutic effects in some neurological disorders via modulation of inflammatory, oxidative and cell-signalling pathways. However, CBD is lipophilic and highly photooxidative with low oral bioavailability in plasma and brain. In this study, we aimed to design and test a CBD microencapsulation method as a drug delivery strategy to improve the absorption of CBD. Additionally, we evaluated the brain uptake of CBD capsules when administered alongside capsules containing a permeation-modifying bile acid, deoxycholic acid (DCA).

Methods

Microcapsules containing either CBD or DCA were formed using the ionic gelation method with 1.5% sodium alginate formulations and 100 mM calcium chloride. C57BL/6J wild type mice randomly assigned to three treatment groups (3–4 mice per group) were administered CBD in the following preparations: 1) CBD capsules, 2) CBD capsules + DCA capsules and 3) naked CBD oil (control). To assess the short-term bioavailability of CBD, plasma and brain samples were collected at 0.3, 1 and 3 hours post administration and CBD levels were analysed with liquid chromatography mass spectrometer.

Results

We produced spherical capsules at 400 ± 50 μm in size. The CBD capsules were calculated to have a drug loading of 2% and an encapsulation efficiency of 23%. Mice that received CBD capsules + DCA capsules showed a 40% and 47% increase in CBD plasma concentration compared to mice on CBD capsules and naked CBD oil, respectively. Furthermore, the CBD capsules + DCA capsules group showed a 48% and 25% increase in CBD brain concentration compared to mice on CBD capsules and naked CBD oil, respectively. In mice treated with CBD capsules + DCA capsules, the brain CBD concentration peaked at 0.3 hours with a 300% increased availability compared to CBD capsules and naked CBD oil groups, which peaked at 1 hour after administration.

Conclusions

The microencapsulation method combined with a permeation enhancer, DCA increased the short-term bioavailability of CBD in plasma and brain.
Multispectral co-occurrence of wavelet coefficients for malignancy assessment of brain tumors
Authors: Roy Shaswati , Maji Pradipta
Published: June 2021

Brain tumor is not most common, but truculent type of cancer. Therefore, correct prediction of its aggressiveness nature at an early stage would influence the treatment strategy. Although several diagnostic methods based on different modalities exist, a pre-operative method for determining tumor malignancy state still remains as an active research area. In this regard, the paper presents a new method for the assessment of tumor grades using conventional MR sequences namely, T1, T1 with contrast enhancement, T2 and FLAIR. The proposed method for tumor gradation is mainly based on feature extraction using multiresolution image analysis and classification using support vector machine. Since the wavelet features of different tumor subregions, obtained from single MR sequence, do not carry equally important information, a wavelet fusion technique is proposed based on the texture information content of each voxel. The concept of texture gradient, used in the proposed algorithm, fuses the wavelet coefficients of the given MR sequences. The feature vector is then derived from the co-occurrence of fused wavelet coefficients. As each wavelet subband contains distinct detail information, a novel concept of multispectral co-occurrence of wavelet coefficients is introduced to capture the spatial correlation among different subbands. It enables to convey more informative features to characterize the tumor type. The effectiveness of the proposed method is analyzed, with respect to six classification performance indices, on BRATS 2012 and BRATS 2014 data sets. The classification accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under curve assessed by the ten-fold cross-validation are 91.3%, 96.8%, 66.7%, 92.4%, 88.4%, and 92.0%, respectively, on real brain MR data.
Qualitative differences in the mindsets associated with dual nature of normative commitment
Authors: Oh Hyun Sung , Sawang Sukanlaya
Published: June 2021

This study aims to o uncover how employees’ normative commitment (sense of obligation) to their organization is experienced in terms of dual normative commitment (moral imperative or indebted obligation) and to describe the potential for different mindsets arising through the dynamic combination of the various components in the commitment profile. Semi-structured interviews were conducted with 16 participants. The interviews were designed to identify the respondents’ perceptions of obligation to their organisation, and their underlying motivational mindset associating with dual nature of normative commitment The interview findings for the affective-normative commitment dominant and the continuance commitment dominant participants were consistent with normative commitment experienced as either moral imperative or an indebted obligation, depending on the relative levels of affective and continuance commitment. All participants irrespective of their commitment profile noted that they had commitment to multiple foci, however, the alignment between commitment to these various foci differed by commitment profile. The qualitative differences among the commitment profiles indicated that the interaction of the commitment components is more complex than current commitment profile propositions suggest and that further theory development beyond the mindsets associated with continuance commitment and affective-normative commitment dominant profiles is required.
Investigation of the effect of anthropogenic land use on the Pănăzii Lake (Romania) catchment area using Cs-137 and Pb-210 radionuclides
Authors: Begy Robert-Csaba , Savin Codrin F. , Kelemen Szabolcs , Veres Daniel , Muntean Octavian-Liviu , Malos Cristian V. , Kovacs Tibor
Published: June 2021

The problem of soil degradation has accentuated over recent decades. Aspects related to soil erosion and its relation to changes in land use as well as anthropogenic influence constitute a topic of great interest. The current study is focused on a soil erosion assessment in relation to land use activities in the Pănăzii Lake catchment area. Fallout radionuclides were used to provide information on soil erosion as well as redistribution rates and patterns. Variations in the sedimentation rate of the lake were also investigated as these reflect periods in which massive erosion events occurred in the lake catchment area. The novelty of this study is the construction of a timescale with regard to the soil erosion events to better understand the relationship between soil erosion and land use activities. In this study, 10 soil profiles and one sediment core from the lake were taken. Soil parameters were determined for each sample. The activities of 210Pb, 137Cs and 226Ra were measured by gamma spectroscopy. For low 210Pb activities, measurements via 210Po using an alpha spectrometer were performed. Soil erosion rates were determined by the 137Cs method and the sedimentation rate calculated by the Constant Rate of Supply (CRS) model. A soil erosion rate of 13.5 t·ha-1·yr-1 was obtained. Three distinct periods could be observed in the evolution of the sedimentation rate. For the first period, between 1880 and 1958, the average deposition rate was 9.2 tons/year, followed by a high deposition period (1960–1991) of 29.6 tons/year and a third period, consisting of the last 30 years, during which the sedimentation rate was 15.7 tons/year. These sedimentation rates fluctuated depending on the main land use activity, which can also be seen in the soil erosion rates that had almost doubled by the time agricultural activities were performed in the area.
Do psychosocial factors mediate the appearance of musculoskeletal symptoms? Evidence of an empirical study about the role of mental workload in computer workers
Authors: Soria-Oliver María , López Jorge S. , Torrano Fermín , García-González Guillermo
Published: June 2021

The emergence of musculoskeletal symptoms (MSSs) in computer workers is a relevant occupational health problem. This study tests a multilevel model of analysis of risk factors in the appearance of musculoskeletal pain and discomfort in computer workers that integrates indicators from different areas: temporal usage patterns, ergonomic factors, psychosocial factors, and individual variables, specifically testing the possible mediating role of the mental workload. A cross-sectional study was performed through online registration with a non-probabilistic sample of 1198 workers from Spanish organizations. The results show that mental workload has a higher association than the rest of the factors with the onset of pain and discomfort in various body areas: neck in men, neck, shoulders and upper back in women. They also support the mediation role of mental workload in the relationship between usage patterns and the appearance of musculoskeletal symptoms. The use of multilevel theoretical models that adequately consider the complexity of the relationships between the different risk factors is necessary for a better understanding and intervention on MSSs in computer workers.
Influence of number of individuals and observations per individual on a model of community structure
Authors: Sunga Julia , Webber Quinn M. R. , Broders Hugh G.
Published: June 2021

Social network analysis is increasingly applied to understand animal groups. However, it is rarely feasible to observe every interaction among all individuals in natural populations. Studies have assessed how missing information affects estimates of individual network positions, but less attention has been paid to metrics that characterize overall network structure such as modularity, clustering coefficient, and density. In cases such as groups displaying fission-fusion dynamics, where subgroups break apart and rejoin in changing conformations, missing information may affect estimates of global network structure differently than in groups with distinctly separated communities due to the influence single individuals can have on the connectivity of the network. Using a bat maternity group showing fission-fusion dynamics, we quantify the effect of missing data on global network measures including community detection. In our system, estimating the number of communities was less reliable than detecting community structure. Further, reliably assorting individual bats into communities required fewer individuals and fewer observations per individual than to estimate the number of communities. Specifically, our metrics of global network structure (i.e., graph density, clustering coefficient, Rcom) approached the ‘real’ values with increasing numbers of observations per individual and, as the number of individuals included increased, the variance in these estimates decreased. Similar to previous studies, we recommend that more observations per individual should be prioritized over including more individuals when resources are limited. We recommend caution when making conclusions about animal social networks when a substantial number of individuals or observations are missing, and when possible, suggest subsampling large datasets to observe how estimates are influenced by sampling intensity. Our study serves as an example of the reliability, or lack thereof, of global network measures with missing information, but further work is needed to determine how estimates will vary with different data collection methods, network structures, and sampling periods.