bluuebunny/crossref_metadata_2025 huggingface dataset:
Railway transport management system transformation in passing to polygon technologies
Authors: Grigoryeva N N
Published: October 2020

Sustainability of the industrial complexes development, economic growth, the country’s foreign economic activity and thus the efficiency of its economy are largely determined by the country’s transportation system development and the railway transportation system in particular. Today the railroad industry performs a number of complex socio-economic functions aimed at modernizing economic development and increasing the rate of scientific-and-technological advance in all the related industries. Under the circumstances, the issue of complete rethink of financial and economic relations in the industry and, accordingly, the entire management system transformation becomes acute.
Communicative problems of management during the construction of transport facilities
Authors: Matveeva G G , Khoroshevskaya Y P , Petrov K S
Published: October 2020

The article discusses the problematic aspects of communication using information and intelligent environments in the construction industry - software systems for BIM modeling and management of production and transport logistics on the construction site. Issues of effective communication in software environments for network management and enterprise management improvement are considered. The article notes the importance of role-based communications in the innovation process. Based on the information approach to the development of communications, we show the possibility of creating institutional forms of innovation in the management of construction production and transport with the help of software packages for BIM modeling and production control and logistics management.
Specifics of global governance in transnational transport corporations
Authors: Suldina Galina , Sulyagina Julia , Eroshkin Sergey , Sorokina Anastasia
Published: October 2020

The article argues the specifics of modern multinational companies, their global economic coverage and serious challenges. Particular attention is paid to the structure of transnational companies (especially international transport companies), as it is very difficult to manage them, because geographically, sometimes being on different continents, they are inevitably, on the one hand, must maintain their recognizability - brand, products, and on the other hand - to meet the specifics of the country where the branch of the company, consumer demands, cultural peculiarities, perhaps even a completely different way of the environment.
Features of risk management in the construction industry in a pandemic with limited use of transport
Authors: Minnullina A , Savoskina E , Frolova E , Sevalnev V , Truntsevsky Y
Published: October 2020

The article highlights the main risks faced by construction companies in a pandemic with limited use of transport. At the same time, one of the significant leaps in the development of companies is updating information technologies that require a new approach with limited possible information transfer between employees. So an important factor in the impact of crisis is the work of office workers on remote access. The article presents the testing of proposed recommendations for evaluating workers in terms of reliability and risk tolerance in a construction company. The results of testing recommendations reflect the possibility or need to restrict access to important documents of company’s internal information environment.
Risk-based approach to the monitoring system for the implementation of state and municipal procurement of transport services
Authors: Karanina Elena , Kartavyh Ksenia
Published: October 2020

The issues of control in the contract system are worked out in the article: the types and mechanisms of control in the field of state and municipal procurement of transport services are analyzed and systematized, the subjects of control and supervisory authorities are identified, the goals and objectives of control are formulated. A model of the system of state and municipal procurements assessment is proposed for assessing the system of state and municipal procurements of transport services based on a risk-based approach, which involves detection a set of elements of the identified risks of the procurement cycle and allowing to fully disclose the nature of the risks of procurement procedures, identify options for the development of events in order to choose a way to minimize losses, and expand the possibilities for improving control from the perspective of ensuring economic security in the field of state procurement of transport services.
Economic mechanisms of public-private partnership in transport construction
Authors: Belova Nadezhda , Voskresenskaya Elena , Vorona-Slivinskaya Lybov
Published: October 2020

A whole complex of transport networks is needed for the quality functioning of the entire economic system of the country: railways, highways, river communications, ports, airports, train stations, etc. The Russian transport framework is based on a network of railways as a rule with radial structure. The country’s Federal highway network has not yet been formed, even in the form of a radial structure, and chord lines are almost not developed. The creation, development, and operation of transport infrastructure — roads, bridges, tunnels, ports, airports — has historically been considered the exclusive prerogative of the state. However, the situation has changed in recent decades. With the growth of requirements to the quality of infrastructure in the context of economic development, the budget deficit and organizational shortcomings that are objectively inherent in the system of public administration are increasingly affected. However, attempts to apply full privatization in this sector are usually unsuccessful, since private owners act solely in the interests of profit, without caring about maintaining the public orientation of the privatized enterprises. For this reason, the mechanisms of public-private partnership, which is an “intermediate” solution between completely public provision of services and full privatization, are becoming more and more common in the world practice. Public-private partnership reflects the growing trend in the global economy of the counter movement of the state and the private sector and is successfully applied not only in transport, but also in energy supply, water supply, public utilities and other areas.
Improving the taxation system in the field of transport services
Authors: Gruzdov G N , Tekiev M V , Revazov V Ch , Byhtina A V
Published: October 2020

Entrepreneurship is one of the most important areas of the economy. However, this is not a specific type of economic activity, but a specific direction of production. It should be noted that entrepreneurship consists of many types of economic activities that are fundamentally different from each other. Every day there are more and more new types of business activities. Sometimes in the practice of entrepreneurship, it would seem that the same types of production activities in analytical research should be evaluated by different criteria. So as a specific example, you can take transport services. here, when using passenger transport as a criterion, which is the object of research, is the seat, and for trucks-the number of cars. But both of these criteria are subject to extensive analytical research. This analysis should be performed by economists with an industry focus. With this in mind, it should be noted that industry criteria for the production sectors of the economy are necessary when determining taxable amounts.
Economic security in the transport industry
Authors: Kivarina Mariya , Vetkina Anna , Sazhneva Lyubov , Kuzmin Aleksey
Published: October 2020

In conditions of economic development and the formation of new economic ties, the uninterrupted operation of transport and its condition significantly affect the level of economic security of the state. The abstract service “transport” is considered by the authors as a complexly structured economic category consisting of three levels. At the first level, a transport service is defined as a form of good; at the second level – as a form of activity; at the third level, in accordance with the social nature of the reproduction of services, a transport service is an economic relation. The article formulates the tasks of ensuring economic security in the provision of transport services and its main components. It is proved that reliable economic security at all territorial levels is possible provided that business entities are stable in the provision of transport services, as their potential is a determining stabilizing factor in anti-crisis development, a guarantee of economic growth and maintaining the country’s economic independence and security. In organizing and managing the transport component of economic security, it is necessary to coordinate the principles of protecting the transport component of security with the interests of the state to ensure economic security in all sectors of the economy, to determine threshold values for indicators and threats to transport security in order to solve the problems of eliminating these threats.
Interactive algorithm for estimating consumer demand for tourism services for sustainable operation of the transport industry
Authors: Sergeev Sergey M , Kurochkina Anna A , Lukina Olga V , Zasenko Vilena E
Published: October 2020

The mass withdrawal from the tourism market and the bankruptcy of operators with many years of history show that there have been radical changes in this type of business. The digital economy, the rapid development of online services, aggregator sites change the structure of demand for travel, recreation and entertainment. First of all, it is necessary to take into account that the generation of zets becomes the most active consumer for these services. Since the global network has become the main source of information and a way of interaction for this age group, it is necessary to change the concept of supply. It is necessary to diversify the assortment sales matrix in addition to traditional vouchers. The expansion of the range of tourism products should be based not only on a deep analysis of market demand, but also on modern algorithms for processing large sets of consumer preference data. It is beneficial to take advantage of digital technologies. It is necessary to take into account a combination of two circumstances: on the one hand Internet surfing potential customers of tourist services, on the other the possibility of tour operators purchasing from search portals and sites aggregators of data on leads (lead), landing pages (Landing Page), CTR (Clickthrough Rate) and other tools of Internet marketing statistics. This work is devoted to the development of an algorithm for processing sets of data on consumer preferences and the development of an optimal market strategy for the supply of tourism services in a competitive business environment. Methods of stochastic optimization, mathematical theory of search for solutions in conditions of uncertainty, computer modeling have been used to solve the problem.
Triads of strategic development of the Russian road transport system
Authors: Gavrilenko N G , Borodulina S A
Published: October 2020

Road freight transport has a significant impact on the Russian economy, which determines the relevance of studying the possibilities of its development. The development of road transport in Russia is determined by the Transport strategy, the implementation of which is difficult to predict in the future. In this regard, the task of increasing the effectiveness of the strategic planning system in the field of road freight transport is urgent. The research was based on a review of scientific literature, the use of methods of system analysis and synthesis, correlation analysis, expert survey, as well as the study of data from the Federal State Statistics Service, information from official websites of government bodies. As a result of our research, we have obtained triads for the development of road freight transport and formed a model for achieving the target indicators set by the Transport strategy of the Russian Federation. The implementation of each indicator depends on the indicators of key external factors, as well as on the traffic functions performed by the human resource at the three levels of management of road transport in the Russian Federation, thus forming the triads “indicator – set of external factors – set of traffic functions”. A set of external factors determines the range of possible values of the indicator, while a set of traffic functions carries out the movement of road freight transport to the set indicators. Presenting each indicator as a triad allows improving the effectiveness of strategic planning in the field of road transport in Russia.
Legal aspects of encouraging and enforcing eco-friendly behavior in the transport sector
Authors: Trikoz E N , Osina D M , Malinovskaya V M
Published: October 2020

It is difficult to overestimate the importance of environmental protection at the present time. Each country takes all possible measures to protect the environment, minimize the sources of its pollution, and encourage eco-friendly behavior of organizations and individuals on its territory. At the same time, one of the main sources of pollution is the transport sector. The paper was prepared using both general scientific and special legal methods and is devoted to the analysis of legal measures applied by different countries to encourage eco-friendly behavior in this area. The research is based on extensive scientific and regulatory material. As a result of the research, it was concluded that at present, in addition to existing measures of legal liability for environmental damage, countries are widely implementing various mechanisms to encourage eco-friendly behavior, including both tax and non-tax measures, which are increasingly proving their reasonableness and effectiveness. The paper considers the experience of Russia, the United States, the European Union as a whole and some of its member states (Italy, Spain, France, Belgium, Sweden), and Japan, including their measures to promote “environmentally friendly” vehicles on the market and encourage energy savings. Based on the conducted research, the necessity of step-by-step harmonization of Russian legislation with international requirements in the field of transport ecology is justified.
Transport industry in the context of the growth of sectors of the Russian economy
Authors: Kazak A N , Oleinikov N N , Gorobets D V , Shamaeva N P
Published: October 2020

An important opportunity to overcome the crisis consequences of COVID-19 is also to restart the economy through solving the accumulated infrastructure problems, including transport. Programs for the development of airports, the railway network, and maritime transport throughout Russia can have a big impact. There is the possibility of supporting technological restructuring in those sectors that are crucial for the future of the Russian economy: transport, aircraft, automotive, in-vestment engineering. To restore activity in the real sector of the economy, including the transport industry, it is necessary to stimulate demand for competitive products and services manufactured by it. Two areas are important here. The first is the provision of basic demand through the public procurement system of federal, regional and municipal services. The second is subsidizing loans for the purchase by the population of durable goods of domestic production (including cars) and mortgages.
First-principles calculation of the effect of Ti content on the structure and properties of TiVNbMo refractory high-entropy alloy
Authors: Chen Lin , Hao Xuanhong , Wang Yueyi , Zhang Xiaowei , Liu Hongxi
Published: October 2020

The virtual crystal approximation (VCA) method based on the Cambridge Sequential Total Energy Package (CASTEP) was used to establish the TiVNbMo refractory high-entropy alloy structure model. The effects of different Ti contents on the elastic and thermodynamic properties of TixVNbMo (x = 1.00, 1.25, 1.50, 2.00) high entropy alloys were calculated. The lattice constants calculation results of TiVNbMo with equal atomic ratio match well with the experimental values of vacuum arc melting, indicating that the VCA method is suitable for the first-principles calculation of TixVNbMo random solid solution. The EOS equation of state is used to determine the energy and volume of the equilibrium structure of the alloy. The elastic constants of TixVNbMo (x = 1.00, 1.25, 1.50, 2.00) high entropy alloys are calculated based on the body-centered cubic structure, and their Young’s modulus anisotropic three-dimensional contour stereograms are drawn. Moreover, the quasi-harmonic Debyeg-Grüneisen model is used to calculate the thermodynamic properties, such as thermal capacity, isothermal body modulus, volumetric thermal expansion coefficient, and Grüneisen parameter with Ti content and temperature.
Clinical Significance of CBC and WBC Morphology in the Diagnosis and Clinical Course of COVID-19 Infection
Authors: Pozdnyakova Olga , Connell Nathan T , Battinelli Elisabeth M , Connors Jean M , Fell Geoffrey , Kim Annette S
Published: October 2020

Objectives

To investigate the clinical significance of numeric and morphologic peripheral blood (PB) changes in coronavirus disease 2019 (COVID-19)–positive patients in predicting the outcome, as well as to compare these changes between critically ill COVID-19–positive and COVID-19–negative patients.

Methods

The study included 90 COVID-19–positive (51 intensive care unit [ICU] and 39 non-ICU) patients and 30 COVID-19–negative ICU patients. We collected CBC parameters (both standard and research) and PB morphologic findings, which were independently scored by two hematopathologists.

Results

All patients with COVID-19 demonstrated striking numeric and morphologic WBC changes, which were different between mild and severe disease states. More severe disease was associated with significant neutrophilia and lymphopenia, which was intensified in critically ill patients. Abnormal WBC morphology, most pronounced in monocytes and lymphocytes, was associated with more mild disease; the changes were lost with disease progression. Between COVID-19–positive and COVID-19–negative ICU patients, significant differences in morphology-associated research parameters were indicative of changes due to the severe acute respiratory syndrome coronavirus 2 virus, including higher RNA content in monocytes, lower RNA content in lymphocytes, and smaller hypogranular neutrophils.

Conclusions

Hospitalized patients with COVID-19 should undergo a comprehensive daily CBC with manual WBC differential to monitor for numerical and morphologic changes predictive of poor outcome and signs of disease progression.
LDL-Cholesterol versus Glucose in Microvascular and Macrovascular Disease
Authors: Emanuelsson Frida , Benn Marianne
Published: October 2020

Background

The causal relationships between increased concentrations of low density lipoprotein (LDL)-cholesterol and glucose and risk of ischemic heart disease are well established. The causal contributions of LDL-cholesterol and glucose to risk of peripheral micro- and macrovascular diseases are less studied, especially in prediabetic stages and in a general population setting.

Content

This review summarizes the current evidence for a causal contribution of LDL-cholesterol and glucose to risk of a spectrum of peripheral micro- and macrovascular diseases and reviews possible underlying disease mechanisms, including differences between vascular compartments, and finally discusses the clinical implications of these findings, including strategies for prevention and treatment.

Combined lines of evidence suggest that LDL-cholesterol has a causal effect on risk of peripheral arterial disease and chronic kidney disease, both of which represent manifestations of macrovascular disease due to atherosclerosis and accumulation of LDL particles in the arterial wall. In contrast, there is limited evidence for a causal effect on risk of microvascular disease. Glucose has a causal effect on risk of both micro- and macrovascular disease. However, most evidence is derived from studies of individuals with diabetes. Further studies in normoglycemic and prediabetic individuals are warranted. Overall, LDL-cholesterol-lowering reduces risk of macrovascular disease, while evidence for a reduction in risk of microvascular disease is inconsistent. Glucose-lowering has a beneficial effect on risk of microvascular diseases and on risk of chronic kidney disease and estimated glomerular filtration rate (eGFR) in some studies, while results on risk of peripheral arterial disease are conflicting.
Effectiveness of Adopting Cloud-Based E-Learning at Qassim University
Authors: Alajlan Norah , Hadwan Mohammed , Ibrahim Dina M
Published: October 2020

The growth of cloud computing (CC) is noticeable in Saudi Arabia, especially in educational institutions. To have an effective E-learning platform, CC is widely used due to its capabilities. This research studying the factors affects the adoption of cloud-based E-learning at Qassim University (QU) from the student’s perspective. A model proposed to measure the effectiveness of the current E-learning system at QU and to identify the significant factors required to encourage students to keep using it. The proposed model includes the theory of motivation, the theory of technology acceptance model and characteristics of CC. Data collected from 114 students analyzed using SmartPLS. Results show the perceived ease of use and extrinsic motivation are significant factors that means have high effects on the intention to use (ITU). While other factors such as availability, collaboration and intrinsic motivation are insignificant that have less or no effect on the ITU cloud-based E-learning.
Sallust, Machiavelli and the Divorce of virtus from res publica
Authors: Regent Nikola
Published: October 2020

Montesquieu famously stated that virtue is the principle of republican government. This article examines how virtue is dissociated from res publica in the works of Sallust, the great Roman republican historian, and Machiavelli, usually regarded as the central figure of the republican tradition. Both thinkers cut the crucial link between virtue and republic, ascribing the former to the main villain of the tradition, Caesar. Furthermore, virtue is simultaneously dissociated from being bonus/buono, a good man/good citizen. The paper examines Sallust’s idea of virtus, and then demonstrates how closely Machiavelli follows him, and how he reaches a similar conclusion. Implications for understanding Machiavelli’s virtù within a framework of republics are shown: it is impossible for a citizen to exhibit virtue and remain good in a truly corrupted republic—in such circumstances one can become virtuous only by working against the public good/res publica.
Challenges and satisfaction in Cardiothoracic Surgery Residency Programmes: insights from a Europe-wide survey
Authors: Cerqueira Rui J , Heuts Samuel , Gollmann-Tepeköylü Can , Syrjälä Simo O , Keijzers Marlies , Zientara Alicja , Jarral Omar A , Jacob Kirolos A , Haunschild Josephina , Ariyaratnam Priyadharshanan , Durko Andras P , Muller Patrick , Myers Patrick O , Sadaba Justo Rafael , Lehtinen Miia L
Published: October 2020

OBJECTIVES

The increasing complexity of surgical patients and working time constraints represent challenges for training. In this study, the European Association for Cardio-Thoracic Surgery Residents’ Committee aimed to evaluate satisfaction with current training programmes across Europe.

METHODS

We conducted an online survey between October 2018 and April 2019, completed by a total of 219 participants from 24 countries.

RESULTS

The average respondent was in the fourth or fifth year of training, mostly on a cardiac surgery pathway. Most trainees follow a 5–6-year programme, with a compulsory final certification exam, but no regular skills evaluation. Only a minority are expected to take the examination by the European Board of Cardiothoracic Surgery. Participants work on average 61.0 ± 13.1 h per week, including 27.1 ± 20.2 on-call. In total, only 19.7% confirmed the implementation of the European Working Time Directive, with 42.0% being unaware that European regulations existed. Having designated time for research was reported by 13.0%, despite 47.0% having a postgraduate degree. On average, respondents rated their satisfaction 7.9 out of 10, although 56.2% of participants were not satisfied with their training opportunities. We found an association between trainee satisfaction and regular skills evaluation, first operator experience and protected research time.

CONCLUSIONS

On average, residents are satisfied with their training, despite significant disparities in the quality and structure of cardiothoracic surgery training across Europe. Areas for potential improvement include increasing structured feedback, research time integration and better working hours compliance. The development of European guidelines on training standards may support this.
Protective effects of pterostilbene against hepatic damage, redox imbalance, mitochondrial dysfunction, and endoplasmic reticulum stress in weanling piglets
Authors: Zhang Hao , Chen Yanan , Li Yue , Jia Peilu , Ji Shuli , Chen Yueping , Wang Tian
Published: October 2020

This investigation evaluated the potential of natural antioxidants, pterostilbene (PT) and its parent compound resveratrol (RSV), to alleviate hepatic damage, redox imbalance, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress in early-weaned piglets. A total of 144 suckling piglets were randomly assigned to four treatments (six replicates per group, n = 6): 1) sow reared, 2) early weaned and fed a basal diet, 3) early weaned and fed the basal diet supplemented with 300 mg/kg PT, or with 4) 300 mg/kg RSV. Early weaning increased plasma alanine aminotransferase (P = 0.004) and aspartate aminotransferase (P = 0.009) activities and hepatic apoptotic rate (P = 0.001) in piglets compared with the sow-reared piglets. Early weaning decreased hepatic adenosine triphosphate (ATP; P = 0.006) content and mitochondrial complexes III (P = 0.019) and IV activities (P = 0.038), but it increased superoxide anion accumulation (P = 0.026) and the expression levels of ER stress markers, such as glucose-regulated protein 78 (P < 0.001), CCAAT/enhancer-binding protein-homologous protein (P = 0.001), and activating transcription factor (ATF) 4 (P = 0.006). PT was superior to RSV at mitigating liver injury and oxidative stress after early weaning, as indicated by decreases in the number of apoptotic cells (P = 0.036) and the levels of superoxide anion (P = 0.002) and 8-hydroxy-2 deoxyguanosine (P < 0.001). PT increased mitochondrial deoxyribonucleic acid content (P = 0.031) and the activities of citrate synthase (P = 0.005), complexes I (P = 0.004) and III (P = 0.011), and ATP synthase (P = 0.041), which may contribute to the mitigation of hepatic ATP deficit (P = 0.017) in the PT-treated weaned piglets. PT also prevented increases in the ER stress marker and ATF 6 expression levels and in the phosphorylation of inositol-requiring enzyme 1 alpha caused by early weaning (P < 0.05). PT increased sirtuin 1 activity (P = 0.031) in the liver of early-weaned piglets than those in the early-weaned piglets fed a basal diet. In conclusion, PT supplementation alleviates liver injury in weanling piglets probably by inhibiting mitochondrial dysfunction and ER stress.
Heroin-Related Compounds and Metabolic Ratios in Postmortem Samples Using LC–MS-MS
Authors: Jakobsson Gerd , Truver Michael T , Wrobel Sonja A , Gréen Henrik , Kronstrand Robert
Published: October 2020

Analysis of postmortem samples with the presence of morphine can sometimes be challenging to interpret. Tolerance complicates interpretation of intoxications and causes of death due to overlap in therapeutic and fatal concentrations. Determination of metabolites and metabolic ratios can potentially differentiate between abstinence, continuous administration, and perhaps time of administration. The purpose of this study was to (a) develop and validate a method for quantitation of morphine-3β-D-glucuronide, morphine-6β-D-glucuronide, normorphine, codeine-6β-D-glucuronide, norcodeine, codeine, 6-acetylmorphine, and ethylmorphine in urine using liquid chromatography–tandem mass spectrometry; (b) apply the method to opiate related deaths; (c) compare metabolic ratios in urine in different causes of death (CoD) and after different drug intakes and (d) compare heroin intoxications in rapid and delayed deaths. Validation parameters such as precision, bias, matrix effects, stability, process efficiency, and dilution integrity were assessed and deemed acceptable. Lower limits of quantitation ranged from 0.01–0.2 μg/mL for all analytes. Autopsy cases (n=135) with paired blood and urine samples were analyzed. Cases were divided into three groups based on CoD; opiate intoxication, intoxication with other drugs than opiates, and other CoD. The cases were classified by intake: codeine (n=42), heroin (n=36), morphine (n=49), and ethylmorphine (n=3). Five cases were classified as mixed intakes and excluded. Heroin intoxications (n=35) were divided into rapid (n=15) or delayed (n=20) deaths. Parent drug groups were compared using metabolic ratio morphine-3β-D-glucuronide/morphine and significant differences were observed between codeine vs morphine (p=0.005) and codeine vs heroin (p≤0.0001). Urine and blood concentrations, and metabolic ratios in rapid and delayed heroin intoxications were compared and determined a significant difference for morphine (p=0.001), codeine (p=0.009), 6-acetylmorphine (p=0.02) in urine, and morphine (p=0.02) in blood, but there was no significant difference (p=0.9) between metabolic ratios. Morphine-3β-D-glucuronide results suggested a period of abstinence prior to death in 25% of the heroin intoxications.
Interim Measures in Antitrust Investigations: An Economic Discussion
Authors: Caminade Juliette , Chapsal Antoine , Penglase Jacob
Published: October 2020

After a period of dormancy, the topic of interim measures (IMs) in antitrust investigations has been brought back into the spotlight in the context of fast-moving digital markets. We analyze historical practices and criteria surrounding IMs in the United States and Europe. Then we present an economic model of the parameters underlying IMs, which can inform the decision of whether to pursue them. The two key parameters needed to determine the benefits of taking an IM are the relative magnitudes of irreparable harm to each party and the probability that the conduct is found to be anticompetitive. A resulting insight is that the overall size of the irreparable harms is not as relevant as their relative size (that is, asymmetry). Increasing both types of harm in the same proportion would not change the decision to use an IM. However, an increase in the overall size of irreparable harms increases the expected benefit from IMs as a tool, if they are used optimally. Finally, we examine the characteristics of the digital economy, finding that while such characteristics are likely to increase the benefits of IMs as a general tool, there is a need to carefully assess IM decisions on a case-by-case basis.
Genomic Adaptations to Salinity Resist Gene Flow in the Evolution of Floridian Watersnakes
Authors: Rautsaw Rhett M , Schramer Tristan D , Acuña Rachel , Arick Lindsay N , DiMeo Mark , Mercier Kathryn P , Schrum Michael , Mason Andrew J , Margres Mark J , Strickland Jason L , Parkinson Christopher L
Published: October 2020

The migration-selection balance often governs the evolution of lineages, and speciation with gene flow is now considered common across the tree of life. Ecological speciation is a process that can facilitate divergence despite gene flow due to strong selective pressures caused by ecological differences; however, the exact traits under selection are often unknown. The transition from freshwater to saltwater habitats provides strong selection targeting traits with osmoregulatory function. Several lineages of North American watersnakes (Nerodia spp.) are known to occur in saltwater habitat and represent a useful system for studying speciation by providing an opportunity to investigate gene flow and evaluate how species boundaries are maintained or degraded. We use double digest restriction-site associated DNA sequencing to characterize the migration-selection balance and test for evidence of ecological divergence within the Nerodia fasciata-clarkii complex in Florida. We find evidence of high intraspecific gene flow with a pattern of isolation-by-distance underlying subspecific lineages. However, we identify genetic structure indicative of reduced gene flow between inland and coastal lineages suggesting divergence due to isolation-by-environment. This pattern is consistent with observed environmental differences where the amount of admixture decreases with increased salinity. Furthermore, we identify significantly enriched terms related to osmoregulatory function among a set of candidate loci, including several genes that have been previously implicated in adaptation to salinity stress. Collectively, our results demonstrate that ecological differences, likely driven by salinity, cause strong divergent selection which promotes divergence in the N. fasciata-clarkii complex despite significant gene flow.
MeDAS: a Metazoan Developmental Alternative Splicing database
Authors: Li Zhidan , Zhang Yiming , Bush Stephen J , Tang Chao , Chen Li , Zhang Dan , Urrutia Araxi O , Lin Jing-wen , Chen Lu
Published: October 2020

Alternative splicing is widespread throughout eukaryotic genomes and greatly increases transcriptomic diversity. Many alternative isoforms have functional roles in developmental processes and are precisely temporally regulated. To facilitate the study of alternative splicing in a developmental context, we created MeDAS, a Metazoan Developmental Alternative Splicing database. MeDAS is an added-value resource that re-analyses publicly archived RNA-seq libraries to provide quantitative data on alternative splicing events as they vary across the time course of development. It has broad temporal and taxonomic scope and is intended to assist the user in identifying trends in alternative splicing throughout development. To create MeDAS, we re-analysed a curated set of 2232 Illumina polyA+ RNA-seq libraries that chart detailed time courses of embryonic and post-natal development across 18 species with a taxonomic range spanning the major metazoan lineages from Caenorhabditis elegans to human. MeDAS is freely available at https://das.chenlulab.com both as raw data tables and as an interactive browser allowing searches by species, tissue, or genomic feature (gene, transcript or exon ID and sequence). Results will provide details on alternative splicing events identified for the queried feature and can be visualised at the gene-, transcript- and exon-level as time courses of expression and inclusion levels, respectively.
Disseminated Mycobacterium bovis Infection Complicated by Meningitis and Stroke: A Case Report
Authors: Clifford Katherine M , Szumowski John D
Published: October 2020

We describe a case of a 19-year-old female presenting with Mycobacterium bovis meningitis, a rarely encountered infection. We discuss the use of pyrosequencing to aid in prompt diagnosis of M. bovis infection, as well as treatment strategies and challenges given the organism’s intrinsic resistance to pyrazinamide.
Gender equality and macroeconomic outcomes: evidence and policy implications
Authors: Kolovich Lisa , Malta Vivian , Newiak Monique , Robinson David
Published: October 2020

A large and growing literature has associated gender equality with better macroeconomic outcomes. However, understanding the channels through which gender equality impacts the economy requires a deeper dive in the main constraints within an economy. Using theoretical and empirical evidence, we explore how gender equality in education feeds into higher human capital levels and thus better macroeconomic outcomes. We also analyse the impact of inequities in the labour market, focusing also on the role of the informal sector. Finally, we provide an overview on policy options to address various gender gaps.
Aphra Behn: Portraiture and The Biographical Account
Authors: van Hensbergen Claudine
Published: October 2020

Scant biographical detail is known about the life of England’s first professional woman writer, Aphra Behn (d.1689), which makes it strange that scholars have shown little interest in surviving portraits of her. This article provides the first comprehensive survey of contemporaneous portraiture of Behn, outlining the provenance of these works and summarizing their various claims to authenticity. In doing so, it highlights how these visual documents of Behn’s life contradict the dominant scholarly view of Behn as a struggling writer who lived a hand-to-mouth existence. Behn herself endorsed one of her portraits, using it to promote her most significant publication up to that point, Poems upon Several Occasions (1684). This portrait neatly reflects the vision of Behn projected through the first biographies of her life which were circulated in the wake of her death. By drawing on Behn’s own ideas about the function of portraits, we can begin to account for the contradictions between two very different visions of Behn: the professional author who stressed that her skills as a writer overcame the restrictions of her gender; and the romantic heroine who promoted an image of her own feminine beauty and gentility.
Management of Leaf Rust and Stripe Rust in Hard Red Spring Wheat at Different Timings of Disease Onset
Authors: Evin Bryn , Meyer Scott , Schuh Casey , Haugen Sam , Halvorson Jessica , Chapara Venkata , Arens Amanda , Friskop Andrew
Published: October 2020

Stripe rust (Puccinia striiformis f. sp. tritici) and leaf rust (Puccinia triticina) can cause significant yield reductions to hard red spring wheat (HRSW) in North Dakota (ND). The use of host resistance and fungicides can successfully manage this disease. However, the combination of them may not be appropriate every year. From 2016 to 2018, fungicide timing by cultivar experiments were conducted to update recommendations for rust management. Experiments were designed in a randomized complete block with a split-plot arrangement. Main plots included three HRSW cultivars that were moderately resistant, moderately susceptible, and susceptible. Subplots included the fungicide timings of Feekes 9, Feekes 10.5.1, a sequential application, and a nontreated control. Field experiments were categorized into three environments depending on rust onset and disease progress. When rust was detected at early heading, the susceptible cultivar benefited from all fungicide application timings. The detection of rust at tillering leaf stages suggested that fungicide treatments statistically lowered disease and in most cases had statistically higher yield, regardless of host resistance. These results suggest that the benefit from a fungicide application to manage leaf rust and stripe rust is highly influenced by the timing of disease onset and level of host resistance. Results will improve fungicide suggestions for HRSW producers in ND.
Epiphyseal Translation as a Predictor of Avascular Necrosis in Unstable Slipped Capital Femoral Epiphysis
Authors: Sinha Preetha , Khedr Ahmed , McClincy Michael P. , Kenkre Tanya S. , Novak Natalie E. , Bosch Patrick
Published: October 2020

Background:

Physeal instability has been shown to be associated with a higher risk of avascular necrosis (AVN) in patients with slipped capital femoral epiphysis (SCFE). The purpose of this study was to identify additional preoperative factors associated with AVN in patients with unstable SCFE.

Methods:

Basic demographic information, chronicity of symptoms, and estimated duration of nonambulatory status were noted. Preoperative radiographs were used to measure the Southwick slip angle, slip severity by Wilson criteria, and epiphyseal translation. Translation was measured by 3 distinct radiographic parameters in the position demonstrating maximal displacement. Postoperative radiographs at the time of most recent follow-up were assessed for the presence of AVN. Translation measurements were tested for inter-rater reliability. Patients who developed AVN were compared with those that did not by Fisher exact test and Wilcoxon tests. Logistic regression assessed the effect of translation on the odds of developing AVN. Receiver operating characteristic curve was plotted to assess any threshold effect.

Results:

Fifty-one patients (55 hips) out of 310 patients (16%) treated for SCFE were considered unstable. Seventeen hips’ unstable SCFE (31%) showed radiographic evidence of AVN. Slip severity by Wilson grade (P=0.009) and epiphyseal translation by all measurements (P< 0.05) were statistically significantly greater among patients who developed AVN. Superior translation had the best inter-rater reliability (intraclass correlation coefficient=0.84). Average superior translation in hips that developed AVN was 17.2 mm compared with 12.9 mm in those that did not (P<0.02). Although the receiver operating characteristic curve did not demonstrate a threshold effect for AVN, it did effectively rule out AVN in cases with <1 cm of superior translation. Age, sex, laterality, chronicity of prodromal symptoms or inability to bear weight, Southwick slip angle, and method of treatment did not vary with the occurrence of AVN.

Conclusions:

Epiphyseal translation, either by Wilson Grade or measured directly, is associated with AVN in patients with an unstable SCFE.

Level of Evidence:

Level II—development of diagnostic criteria.
Safety and Feasibility of Cervical Pedicle Screw Insertion in Pediatric Subaxial Cervical Spine Without Navigation: A Retrospective Cohort Study
Authors: Garg Bhavuk , Mehta Nishank
Published: October 2020

Background:

The use of cervical pedicle screws (CPSs) in pediatric subaxial cervical spine has been scarcely reported in the literature. The biomechanical superiority of CPS over other methods of fixation is beneficial in surgery for correcting severe, rigid cervical/cervicothoracic deformity. Our study aims to assess the safety, efficacy, and feasibility of CPS fixation in pediatric subaxial cervical spine without intraoperative navigation.

Methods:

Eight pediatric patients requiring rigid subaxial cervical spine fixation for complex cervical deformities were operated at a single center between 2014 and 2016. Their hospital records and imaging were retrospectively studied. The feasibility of inserting CPS was assessed by studying pedicle morphometry on preoperative computed tomography (CT) scans. Aberrant vertebral artery anatomy was ruled out using CT angiography. CPS were inserted into selected pedicles without navigation. Postoperative CT scans were studied to look for screw containment within pedicles. Complications were noted and clinicoradiologic follow-up was for a minimum of 36 months.

Results:

Thirty-seven CPS were inserted in 8 pediatric patients with a mean age of 9.2 years (range: 5 to 13 y). Surgery was done for complex cervical deformities due to various causes—neglected cervical spine trauma (n=3), posttubercular kyphosis (n=2), cervicothoracic scoliosis (n=2), and cervicothoracic osteoblastoma (n=1). The level-wise distribution of the inserted CPS was: C3=4, C4=6, C5=10, C6=10, and C7=7. Postoperative CT scans showed grade-1 medial cortical breach in 5/37 screws and grade-2 medial cortical breach in a single screw (16%). No perioperative complications were noted. At a mean follow-up of 3.6 years (range: 3 to 4.33 y), no patient had implant failure or deformity progression.

Conclusions:

CPS insertion in pediatric subaxial cervical spine without neuronavigation is safe, feasible, and effective in carefully selected cases. Biomechanical advantages of CPS can be extended to the pediatric subaxial cervical spine.

Level of Evidence:

Level IV—retrospective cohort.
Trends in Adolescent Hip Arthroscopy From the PHIS Database 2008–2018
Authors: Hassan Mahad M. , Hussain Zaamin B. , Rahman Omar F. , Kocher Mininder S.
Published: October 2020

Background:

Previous studies have suggested that hip arthroscopy has been performed with increasing frequency. Few studies have examined this trend in the adolescent population. The purpose of this study was to evaluate the trend in the frequency of hip arthroscopy in adolescents standardized by total orthopaedic surgeries in adolescents at pediatric hospitals in the United States.

Methods:

The Pediatric Health Information System (PHIS) database was queried for patients aged 10 to 19 years who underwent orthopaedic surgery at any of the PHIS-participating hospitals from 2008 to 2018. The subgroup of patients in this age cohort who underwent hip arthroscopy was identified using Current Procedural Terminology procedure codes. The yearly rate was expressed as the number of hip arthroscopies per 1000 orthopaedic surgeries. A linear model was used to fit the data and illustrate the relative trend.

Results:

A total of 432,309 orthopaedic surgeries including 9491 hip arthroscopies were performed for patients 10 to 19 years of age. Hip arthroscopies were performed at a yearly rate of 22 per 1000 orthopaedic surgeries. Over the 10-year period, the number of hip arthroscopies increased 6.2-fold, whereas the number of orthopaedic procedures increased 1.6-fold. There was a 3.9-fold increase in hip arthroscopies relative to total orthopaedic surgeries.

Conclusions:

The number of hip arthroscopic procedures in adolescent patients has increased by 3.9-fold times relative to total orthopaedic surgeries in adolescents over a 10-year span, on the basis of data from PHIS-participating institutions. This finding mirrors the trends in the adult population over similar time periods. This may be because of increasing participation in sports in the adolescent population, and a better understanding of the diagnosis and treatment of femoroacetabular impingement and other sports-related hip pathologies.

Level of Evidence:

Level IV.