bluuebunny/crossref_metadata_2025 huggingface dataset:
Crack Detection in Images of Masonry Using CNNs
Authors: Hallee Mitchell J. , Napolitano Rebecca K. , Reinhart Wesley F. , Glisic Branko
Published: July 2021

While there is a significant body of research on crack detection by computer vision methods in concrete and asphalt, less attention has been given to masonry. We train a convolutional neural network (CNN) on images of brick walls built in a laboratory environment and test its ability to detect cracks in images of brick-and-mortar structures both in the laboratory and on real-world images taken from the internet. We also compare the performance of the CNN to a variety of simpler classifiers operating on handcrafted features. We find that the CNN performed better on the domain adaptation from laboratory to real-world images than these simple models. However, we also find that performance is significantly better in performing the reverse domain adaptation task, where the simple classifiers are trained on real-world images and tested on the laboratory images. This work demonstrates the ability to detect cracks in images of masonry using a variety of machine learning methods and provides guidance for improving the reliability of such models when performing domain adaptation for crack detection in masonry.
Lung Auscultation Using the Smartphone—Feasibility Study in Real-World Clinical Practice
Authors: Ferreira-Cardoso Henrique , Jácome Cristina , Silva Sónia , Amorim Adelina , Redondo Margarida T. , Fontoura-Matias José , Vicente-Ferreira Margarida , Vieira-Marques Pedro , Valente José , Almeida Rute , Fonseca João Almeida , Azevedo Inês
Published: July 2021

Conventional lung auscultation is essential in the management of respiratory diseases. However, detecting adventitious sounds outside medical facilities remains challenging. We assessed the feasibility of lung auscultation using the smartphone built-in microphone in real-world clinical practice. We recruited 134 patients (median[interquartile range] 16[11–22.25]y; 54% male; 31% cystic fibrosis, 29% other respiratory diseases, 28% asthma; 12% no respiratory diseases) at the Pediatrics and Pulmonology departments of a tertiary hospital. First, clinicians performed conventional auscultation with analog stethoscopes at 4 locations (trachea, right anterior chest, right and left lung bases), and documented any adventitious sounds. Then, smartphone auscultation was recorded twice in the same four locations. The recordings (n = 1060) were classified by two annotators. Seventy-three percent of recordings had quality (obtained in 92% of the participants), with the quality proportion being higher at the trachea (82%) and in the children’s group (75%). Adventitious sounds were present in only 35% of the participants and 14% of the recordings, which may have contributed to the fair agreement between conventional and smartphone auscultation (85%; k = 0.35(95% CI 0.26–0.44)). Our results show that smartphone auscultation was feasible, but further investigation is required to improve its agreement with conventional auscultation.
Secure and Efficient High Throughput Medium Access Control for Vehicular Ad-Hoc Network
Authors: Al-Absi Mohammed Abdulhakim , Al-Absi Ahmed Abdulhakim , Fu Rui , Kim Ki-Hwan , Lee Young-Sil , Lee Byung-Gook , Lee Sang-Gon , Lee Hoon-Jae
Published: July 2021

The evolution of the internet has led to the growth of smart application requirements on the go in the vehicular ad hoc network (VANET). VANET enables vehicles to communicate smartly among themselves wirelessly. Increasing usage of wireless technology induces many security vulnerabilities. Therefore, effective security and authentication mechanism is needed to prevent an intruder. However, authentication may breach user privacy such as location or identity. Cryptography-based approach aids in preserving the privacy of the user. However, the existing security models incur communication and key management overhead since they are designed considering a third-party server. To overcome the research issue, this work presents an efficient security model namely secure performance enriched channel allocation (S−PECA) by using commutative RSA. This work further presents the commutative property of the proposed security scheme. Experiments conducted to evaluate the performance of the proposed S−PECA over state-of-the-art models show significant improvement. The outcome shows that S−PECA minimizes collision and maximizes system throughput considering different radio propagation environments.
Fast Beam Training Technique for Millimeter-Wave Cellular Systems with an Intelligent Reflective Surface
Authors: Sultan Qasim , Kim Yeong-Jun , Khan Mohammed-Saquib , Cho Yong-Soo
Published: July 2021

The concept of an intelligent reflecting surface (IRS) has recently emerged as a promising solution for improving the coverage and energy/spectral efficiency of future wireless communication systems. However, as the number of reflecting elements in an IRS increase, the beam training protocol in IRS-assisted millimeter-wave (mmWave) cellular systems requires a large beam training time because it needs to find the best beam pairs for the link between the base station (BS) and the IRS, as well as the link between the IRS and the mobile station (MS). In this paper, a fast beam training technique for IRS-assisted mmWave cellular systems with a uniform rectangular array is proposed for detecting the best beam pairs of BS-IRS and IRS-MS links simultaneously. Two different types of beam training signals (BTSs) are proposed to distinguish simultaneously transmitted beams from the BSs in multi-cell multi-beam environments: the Zadoff–Chu sequence based BTS (ZC-BTS) and m-sequence based BTS (m-BTS). The correlation properties of ZC-BTSs and m-BTSs are analyzed in multi-cell multi-beam environments. In addition, the effect of symbol time offset on the ZC-BTS and m-BTS is analyzed. Finally, simulation results reveal that the proposed technique can significantly reduce the beam training time for IRS-assisted mmWave cellular systems.
Regulatory, Legal, and Market Aspects of Smart Wearables for Cardiac Monitoring
Authors: Brönneke Jan Benedikt , Müller Jennifer , Mouratis Konstantinos , Hagen Julia , Stern Ariel Dora
Published: July 2021

In the area of cardiac monitoring, the use of digitally driven technologies is on the rise. While the development of medical products is advancing rapidly, allowing for new use-cases in cardiac monitoring and other areas, regulatory and legal requirements that govern market access are often evolving slowly, sometimes creating market barriers. This article gives a brief overview of the existing clinical studies regarding the use of smart wearables in cardiac monitoring and provides insight into the main regulatory and legal aspects that need to be considered when such products are intended to be used in a health care setting. Based on this brief overview, the article elaborates on the specific requirements in the main areas of authorization/certification and reimbursement/compensation, as well as data protection and data security. Three case studies are presented as examples of specific market access procedures: the USA, Germany, and Belgium. This article concludes that, despite the differences in specific requirements, market access pathways in most countries are characterized by a number of similarities, which should be considered early on in product development. The article also elaborates on how regulatory and legal requirements are currently being adapted for digitally driven wearables and proposes an ongoing evolution of these requirements to facilitate market access for beneficial medical technology in the future.
Experimental Study on Flocculation Effect of Tangential Velocity in a Cone-Plate Clarifier
Authors: Zhang Yulong , Liu Peikun , Xiao Linjing , Zhang Yuekan , Yang Xinghua , Jiang Lanyue
Published: July 2021

A large number of particles with small size and light density in mine water are difficult to remove by traditional separation equipment. In order to improve the efficiency of mine water treatment, a cone-plate clarifier is proposed in this paper. The particle size distribution and their fragmentation fractal dimension were studied in 15 sampling points of the cone-plate clarifier to elucidate the process of floc growth and settling. The influence of the tangential inlet velocity size distribution characteristics was also studied. The results showed that the cone-plate clarifier can effectively improve suspended solids and turbidity removal efficiency. The floc growth and settlement courses are shown in the charts. The cone-plate clarifier was divided into four zones: micro flocculation, floc growing, settlement, and exit pipe. Because the fluid enters the cone-plate clarifier tangentially, the value of the inlet velocity and the tangential velocity are equal at the inlet feed. With the increase in tangential velocity, the flocculation efficiency first increased and then decreased. Comprehensive analysis of the particle greater than 50 μm in the effluent showed that the optimal inlet was qual to 1.63 m/s. By fitting the equations, the optimal SS and turbidity removal efficiency reached the maximum values of 92.04% and 80.18% at the inlet velocity of 1.86 m/s and 1.77 m/s, respectively.
Thermal Energy Performance Simulation of a Residential Building Retrofitted with Passive Design Strategies: A Case Study in Mexico
Authors: Vargas Ana Paola , Hamui Leon
Published: July 2021

High energy consumption as a result of an inefficient design has both economic and environmental repercussions throughout the life cycle of a building. In Mexico, the residential sector is the third-largest final energy consumer, therefore improving the performance of existing buildings is considered an effective method in achieving energy savings. Moreover, in Mexico warm climate regions predominate, which impacts energy consumption. This article examines a linked, single-family house located in the hot-humid climate city of Villahermosa, Tabasco (México). DesignBuilder software was used to conduct the thermal energy performance simulation of the existing building (base case) and to evaluate the energy-saving potentials by implementing different passive design strategies. As a result, the annual electricity consumption of the base case decreased a maximum of 2.0% with the passive design strategy in exterior windows, 4.9% in walls and, 13.7% reduction in roofs, the latter being the enclosure with the greatest reduction achieved. Nevertheless, a final adaptation proposal with the passive design strategies, whose results represented the highest energy savings, accomplished a total reduction of 23.5% with a payback period of 5.8 years.
The Green Side of Industry: The Drivers and the Impacts of ECO-Innovations in Brazil
Authors: Sperotto Fernanda Q. , Tartaruga Iván G. P.
Published: July 2021

This study aimed to provide an overview of eco-innovations in the Brazilian industry. To address this issue, we analyzed specific data of eco-innovative companies. In addition, we applied the cluster heatmap technique, which allowed us to analyze the different drivers and impacts of eco-innovations in different sectors. According to the results, companies that stated that innovation made it possible to reduce their environmental impact represent a third of all innovators. Moreover, they are companies that have shown greater effort to innovate and greater susceptibility to the benefits and obstacles of innovation. Furthermore, the eco-innovation strategy is mainly driven by market factors, such as reputation and codes of good practice. The impacts are mainly associated with the use of more widespread and less complex technologies, such as recycling. In addition to these results, the study considers some alternatives to guide the innovation policy, especially related to eco-innovations in semi-peripherical countries.
Effects of Climate Change on Cultivation Patterns and Climate Suitability of Spring Maize in Inner Mongolia
Authors: Yang Xiujuan , Sun Jiying , Gao Julin , Qiao Shuaishuai , Zhang Baolin , Bao Haizhu , Feng Xinwei , Wang Songyu
Published: July 2021

Climate change has caused significant alterations in crop cultivation patterns and has affected crop suitability as well as its production. In this study, we investigated the changes in cultivation patterns and climate suitability of spring maize in Inner Mongolia from 1959 to 2018. We used the daily meteorological data from 50 weather stations and growth period data of spring maize from nine agrometeorological stations. In addition, the quantitative and interdecadal relationship between climate suitability of regions and climate-induced crop yield was analyzed using stepwise regression and cross wavelet transform. The results show that: (1) The planting boundaries of different spring maize maturity types extend to the north and east. In the middle part, early maturity maize has been replaced by medium maturity maize. The unsuitable planting areas in Northeast Inner Mongolia are decreasing, and the early maturity areas are increasing. (2) The climate suitability for spring maize planting areas is increasing. However, variations occur between different regions; the eastern region has the highest climate suitability (Sz = 0.67), but the overall trend is decreasing in this region. Whereas the central region has moderate suitability (Sz = 0.62), with a significantly increasing trend (p < 0.05). The western region is lower (Sz = 0.60) and the trend is not significant. (3) Climate suitability and climate-induced yields are generally positively correlated. The primary factors affecting climate-induced yields are sunshine hours, followed by climate suitability, rainfall, and temperature. The cross-wavelet transform shows that climate suitability and climate-induced yield have greater periodicity in the late growth period. Appropriate expansion of the planting range of medium-late maturity spring maize can fully adapt to the impact of climate warming. Therefore, it is necessary to study suitability trends of regions to adopt comprehensive maize production measures.
Preparing an Organization for Sustainability Transitions—The Making of Boundary Spanners through Design Training
Authors: Yström Anna , Agogué Marine , Rampa Romain
Published: July 2021

Organizations today need to adapt their operations for a more sustainable future, and the transition management literature has highlighted the need for individuals who can collaborate with others to find new paths forward. Essentially, these individuals are boundary spanners with specific skills and competences to bridge diverging perspectives and facilitate knowledge dissemination and integration. Such individuals become critical change agents in organizations and essential in preparing the organization for sustainability transitions. The purpose of this study is to explore how organizations can enable and encourage individuals to take on this role and develop the skills and competences needed to become boundary spanners. Based on a case study set in a large Canadian energy corporation striving to shift towards more sustainable operations, our paper explores the emergence of boundary spanners, focusing on the effects of a design training program in supporting such roles in the organization. Our findings outline essential characteristics of boundary spanners; through illustrative career trajectories of four individuals participating in the training program, we show how the training program contributed to the emergence of boundary spanners.
Microscopic Traffic Simulation as a Decision Support System for Road Diet and Tactical Urbanism Strategies
Authors: Liu Bernice , Mehrara Molan Amirarsalan , Pande Anurag , Howard Jonathan , Alexander Serena , Luo Zhiliang
Published: July 2021

Urban street networks in the United States have been primarily designed for automobile traffic with negligible considerations to non-motorized transportation users. Due to environmental issues and quality of life concerns, communities are reclaiming street spaces for active modes and slowing the speeds in their downtown. Moreover, tactical urbanism, i.e., the use of street space for innovative purposes other than moving automobile traffic, is becoming attractive due to reduced automobile travel demand and the need for outdoor activities in the age of the COVID-19 pandemic. This study provides details of the modeling of an urban downtown network (in the City of San Jose) using microscopic traffic simulation. The model is then applied to evaluate the effectiveness of street design changes at varying demand scenarios. The microsimulation approach was chosen because it allows for the detailed modeling and visualization of the transportation networks, including movements of individual vehicles, bicyclists, and pedestrians. The street design change demonstrated here involves one-way to two-way street conversion, but the framework of network-wide impact evaluation may also be used for complete street conversions. The base conditions network was also tested under different travel demand reduction scenarios (10%, 20%, and 30%) to identify the corridors in the city network in which the tactical urbanism strategies (e.g., open-air dining) may be best accommodated. The study provides framework for the use of a microscopic model as part of a decision support system to evaluate and effectively implement complete streets/tactical urbanism strategies.
CO2 Emission and Cost Optimization of Concrete-Filled Steel Tubular (CFST) Columns Using Metaheuristic Algorithms
Authors: Cakiroglu Celal , Islam Kamrul , Bekdaş Gebrail , Billah Muntasir
Published: July 2021

Concrete-filled steel tubular columns have garnered wide interest among researchers due to their favorable structural characteristics. To attain the best possible performance from concrete-filled steel tubular columns while reducing the cost, the use of optimization algorithms is indispensable. In this regard, metaheuristic algorithms are finding increasing application in structural engineering due to their high efficiency. Various equations that predict the ultimate axial load-carrying capacity (Nu) of concrete-filled steel tubular columns are available in design codes as well as in the research literature. However, most of these equations are only applicable within certain parameter ranges. To overcome this limitation, the present study adopts a recently developed set of equations for the prediction of Nu that have broader ranges of applicability. Furthermore, a newly developed metaheuristic algorithm, called the social spider algorithm, is introduced and applied in optimizing the cross-section of circular concrete-filled steel tubular columns. The improvement of the structural dimensioning under the Nu constraint is demonstrated. The objective underlying the optimization presented here is to minimize the CO2 emission and cost associated with the fabrication of concrete-filled steel tubular stub columns. In this context, the relationships between the cross-sectional dimensioning of circular concrete-filled steel tubular columns and the associated CO2 emissions and cost are characterized and visualized.
The Spatiotemporal Characteristics and Climatic Factors of COVID-19 in Wuhan, China
Authors: Lin Qiaowen , Ou Guoliang , Wang Renyang , Li Yanan , Zhao Yi , Dong Zijun
Published: July 2021

COVID-19 is threatening the whole world. This paper aims to explore the correlation between climatic factors and the morbidity of COVID-19 in Wuhan, China, mainly by using a geographic detector and GWR model. It was found that the response of the morbidity of COVID-19 to meteorological factors in Wuhan is different at different stages. On the whole, the morbidity of COVID-19 has a strong spatial aggregation, mainly concentrated in the central area of Wuhan City. There is a positive correlation between wind speed and the spread of COVID-19, while temperature has a negative correlation. There is a positive correlation between air pressure and the number of COVID-19 cases. Rainfall is not significantly correlated with the spread of COVID-19. It is concluded that wind speed, relative humidity, temperature, and air pressure are important meteorological factors affecting the spread of COVID-19 in Wuhan. Any two variables have greater interaction with the spatial distribution of the incidence rate of COVID-19 than any one factor alone. Those findings not only provide a new insight for the key intervention measures and the optimal allocation of health care resources accordingly but also lay a theoretical foundation for disease prevention, disease intervention and health services.
NMR Properties of the Cyanide Anion, a Quasisymmetric Two-Faced Hydrogen Bonding Acceptor
Authors: Shenderovich Ilya G. , Denisov Gleb S.
Published: July 2021

The isotopically enriched cyanide anion, (13C≡15N)−, has a great potential as the NMR probe of non-covalent interactions. However, hydrogen cyanide is highly toxic and can decompose explosively. It is therefore desirable to be able to theoretically estimate any valuable results of certain experiments in advance in order to carry out experimental studies only for the most suitable molecular systems. We report the effect of hydrogen bonding on NMR properties of 15N≡13CH···X and 13C≡15NH···X hydrogen bonding complexes in solution, where X = 19F, 15N, and O=31P, calculated at the ωB97XD/def2tzvp and the polarizable continuum model (PCM) approximations. In many cases, the isotropic 13C and 15N chemical shieldings of the cyanide anion are not the most informative NMR properties of such complexes. Instead, the anisotropy of these chemical shieldings and the values of scalar coupling constants, including those across hydrogen bonds, can be used to characterize the geometry of such complexes in solids and solutions. 1J(15N13C) strongly correlates with the length of the N≡C bond.
Space–Time Physics in Background-Independent Theories of Quantum Gravity
Authors: Bojowald Martin
Published: July 2021

Background independence is often emphasized as an important property of a quantum theory of gravity that takes seriously the geometrical nature of general relativity. In a background-independent formulation, quantum gravity should determine not only the dynamics of space–time but also its geometry, which may have equally important implications for claims of potential physical observations. One of the leading candidates for background-independent quantum gravity is loop quantum gravity. By combining and interpreting several recent results, it is shown here how the canonical nature of this theory makes it possible to perform a complete space–time analysis in various models that have been proposed in this setting. In spite of the background-independent starting point, all these models turned out to be non-geometrical and even inconsistent to varying degrees, unless strong modifications of Riemannian geometry are taken into account. This outcome leads to several implications for potential observations as well as lessons for other background-independent approaches.
Quaternary Interaction of the HIV-1 Envelope Trimer with CD4 and Neutralizing Antibodies
Authors: Liu Qingbo , Zhang Peng , Lusso Paolo
Published: July 2021

The entry of HIV-1 into host cells is initiated by the interaction of the viral envelope (Env) spike with the CD4 receptor. During this process, the spike undergoes a series of conformational changes that eventually lead to the exposure of the fusion peptide located at the N-terminus of the transmembrane glycoprotein, gp41. Recent structural and functional studies have provided important insights into the interaction of Env with CD4 at various stages. However, a fine elucidation of the earliest events of CD4 contact and its immediate effect on the Env conformation remains a challenge for investigation. Here, we summarize the discovery of the quaternary nature of the CD4-binding site in the HIV-1 Env and the role of quaternary contact in the functional interaction with the CD4 receptor. We propose two models for this initial contact based on the current knowledge and discuss how a better understanding of the quaternary interaction may lead to improved immunogens and antibodies targeting the CD4-binding site.
Targeting JAK/STAT Signaling Antagonizes Resistance to Oncolytic Reovirus Therapy Driven by Prior Infection with HTLV-1 in Models of T-Cell Lymphoma
Authors: Islam Shariful , Espitia Claudia M. , Persky Daniel O. , Carew Jennifer S. , Nawrocki Steffan T.
Published: July 2021

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that infects at least 10 million people worldwide and is associated with the development of T-cell lymphoma (TCL). The treatment of TCL remains challenging and new treatment options are urgently needed. With the goal of developing a novel therapeutic approach for TCL, we investigated the activity of the clinical formulation of oncolytic reovirus (Reolysin, Pelareorep) in TCL models. Our studies revealed that HTLV-1-negative TCL cells were highly sensitive to Reolysin-induced cell death, but HTLV-1-positive TCL cells were resistant. Consistent with these data, reovirus displayed significant viral accumulation in HTLV-1-negative cells, but failed to efficiently replicate in HTLV-1-positive cells. Transcriptome analyses of HTLV-1-positive vs. negative cells revealed a significant increase in genes associated with retroviral infection including interleukin-13 and signal transducer and activator of transcription 5 (STAT5). To investigate the relationship between HTLV-1 status and sensitivity to Reolysin, we infected HTLV-1-negative cells with HTLV-1. The presence of HTLV-1 resulted in significantly decreased sensitivity to Reolysin. Treatment with the JAK inhibitor ruxolitinib suppressed STAT5 phosphorylation and expression of the key anti-viral response protein MX1 and enhanced the anti-TCL activity of Reolysin in both HTLV-1-positive and negative cells. Our data demonstrate that the inhibition of the JAK/STAT pathway can be used as a novel approach to antagonize the resistance of HTLV-1-positive cells to oncolytic virus therapy.
Previous Usutu Virus Exposure Partially Protects Magpies (Pica pica) against West Nile Virus Disease But Does Not Prevent Horizontal Transmission
Authors: Escribano-Romero Estela , Jiménez de Oya Nereida , Camacho María-Cruz , Blázquez Ana-Belén , Martín-Acebes Miguel A. , Risalde Maria A. , Muriel Laura , Saiz Juan-Carlos , Höfle Ursula
Published: July 2021

The mosquito-borne flaviviruses USUV and WNV are known to co-circulate in large parts of Europe. Both are a public health concern, and USUV has been the cause of epizootics in both wild and domestic birds, and neurological cases in humans in Europe. Here, we explore the susceptibility of magpies to experimental USUV infection, and how previous exposure to USUV would affect infection with WNV. None of the magpies exposed to USUV showed clinical signs, viremia, or detectable neutralizing antibodies. After challenge with a neurovirulent WNV strain, neither viremia, viral titer of WNV in vascular feathers, nor neutralizing antibody titers of previously USUV-exposed magpies differed significantly with respect to magpies that had not previously been exposed to USUV. However, 75% (6/8) of the USUV-exposed birds survived, while only 22.2% (2/9) of those not previously exposed to USUV survived. WNV antigen labeling by immunohistochemistry in tissues was less evident and more restricted in magpies exposed to USUV prior to challenge with WNV. Our data indicate that previous exposure to USUV partially protects magpies against a lethal challenge with WNV, while it does not prevent viremia and direct transmission, although the mechanism is unclear. These results are relevant for flavivirus ecology and contention.
Phylogenetic Analysis of Massilia phlebovirus in Portugal
Authors: Amaro Fátima , Zé-Zé Líbia , Lourenço José , Giovanetti Marta , Becker Stefanie Christine , Alves Maria João
Published: July 2021

In the last two decades, molecular surveys of arboviruses have enabled the identification of several new viruses, contributing to the knowledge of viral diversity and providing important epidemiological data regarding possible new emerging viruses. A combination of diagnostic assays, Illumina sequencing and phylogenetic inference are here used to characterize two new Massilia phlebovirus strains isolated from sandflies collected in the Arrábida region, Portugal. Whole genome sequence analysis enabled their identification as reassortants and the recognition of genomic variants co-circulating in Portugal. Much is still unknown about the life cycle, geographic range, evolutionary forces and public health importance of these viruses in Portugal and elsewhere, and more studies are needed.
Seroprevalence of SARS-CoV-2 Binding and Neutralizing Antibodies in Healthcare Workers during the Epidemic Peak in Referral Hospitals and Quarantine Sites: Saudi Arabia
Authors: Alhabbab Rowa Y. , Alsaieedi Ahdab , Algaissi Abdullah , Almahboub Sara , Al-Raddadi Rajaa M. , Shabouni Omaima I. , Alhabbab Rahaf , Alfaraj Abdulelah A. , Alamri Sawsan S. , Aljehani Najwa D. , Abdulal Rwaa H. , Alfaleh Mohamed A. , Abujamel Turki S. , Alkayyal Almohanad A. , Mahmoud Ahmad Bakur , Abuzenadah Adel M. , Hashem Anwar M.
Published: July 2021

Healthcare workers (HCWs) are at high risk for SARS-CoV-2 infection compared to the general population. Here, we aimed to evaluate and characterize the SARS-CoV-2 seropositivity rate in randomly collected samples among HCWs from the largest referral hospitals and quarantine sites during the peak of the COVID-19 epidemic in the city of Jeddah, the second largest city in Saudi Arabia, using a cross-sectional analytic study design. Out of 693 participants recruited from 29 June to 10 August 2020, 223 (32.2%, 95% CI: 28.8–35.8) were found to be confirmed seropositive for SARS-CoV-2 antibodies, and among those 197 (88.3%) had never been diagnosed with COVID-19. Seropositivity was not significantly associated with participants reporting COVID-19 compatible symptoms as most seropositive HCW participants 140 (62.8%) were asymptomatic. The large proportion of asymptomatic SARS-CoV-2 cases detected in our study demands periodic testing as a general hospital policy.
Membrane Insertion of the M13 Minor Coat Protein G3p Is Dependent on YidC and the SecAYEG Translocase
Authors: Kleinbeck Farina , Kuhn Andreas
Published: July 2021

The minor coat protein G3p of bacteriophage M13 is the key component for the host interaction of this virus and binds to Escherichia coli at the tip of the F pili. As we show here, during the biosynthesis of G3p as a preprotein, the signal sequence interacts primarily with SecY, whereas the hydrophobic anchor sequence at the C-terminus interacts with YidC. Using arrested nascent chains and thiol crosslinking, we show here that the ribosome-exposed signal sequence is first contacted by SecY but not by YidC, suggesting that only SecYEG is involved at this early stage. The protein has a large periplasmic domain, a hydrophobic anchor sequence of 21 residues and a short C-terminal tail that remains in the cytoplasm. During the later synthesis of the entire G3p, the residues 387, 389 and 392 in anchor domain contact YidC in its hydrophobic slide to hold translocation of the C-terminal tail. Finally, the protein is processed by leader peptidase and assembled into new progeny phage particles that are extruded out of the cell.
Reanalysis of Soil Moisture Used for Rainfall Thresholds for Rainfall-Induced Landslides: The Italian Case Study
Authors: Bezak Nejc , Jemec Auflič Mateja , Mikoš Matjaž
Published: July 2021

Landslides are one of the most frequent natural disasters that can endanger human lives and property. Therefore, prediction of landslides is essential to reduce economic damage and save human lives. Numerous methods have been developed for the prediction of landslides triggering, ranging from simple methods that include empirical rainfall thresholds, to more complex ones that use sophisticated physically- or conceptually-based models. Reanalysis of soil moisture data could be one option to improve landslide forecasting accuracy. This study used the publicly available FraneItalia database hat contains almost 9000 landslide events that occurred in the 2010–2017 period in Italy. The Copernicus Uncertainties in Ensembles of Regional Reanalyses (UERRA) dataset was used to obtain precipitation and volumetric soil moisture data. The results of this study indicated that precipitation information is still a much better predictor of landslides triggering compared to the reanalyzed (i.e., not very detailed) soil moisture data. This conclusion is valid both for local (i.e., grid) and regional (i.e., catchment-based) scales. Additionally, at the regional scale, soil moisture data can only predict a few landslide events (i.e., on average around one) that are not otherwise predicted by the simple empirical rainfall threshold approach; however, this approach on average, predicted around 18 events (i.e., 55% of all events). Despite this, additional investigation is needed using other (more complete) landslide databases and other (more detailed) soil moisture products.
Low Frequency Oscillations in a Hydroelectric Generating System to the Variability of Wind and Solar Power
Authors: Xu Beibei , Lei Liuwei , Zhao Ziwen , Jiang Wei , Xiao Shu , Li Huanhuan , Zhang Junzhi , Chen Diyi
Published: July 2021

The penetration of multiple integrated renewable energies to the power grid are relevant for decision making in energy policy, environment and business. Such an electricity penetration is affected by the intermittent and volatile characteristics of integrated energies, mostly significantly related to the safe and stable electricity production and supply in real world. Here, this paper focuses on the low frequency oscillation analysis of the hydropower generation response to the wind and solar variability. To enable this analysis, a hybrid model of hydropower system integrating with the wind and solar power system is presented. The Nyquist and root-locus stability methods are used to investigate the sensitivity performance of the hydropower governor to the fluctuation of the integrated renewable energies. Additionally, to quantify the risk of the hybrid system, the low frequency oscillation response of hydropower system to wind/solar/hydropower quota and transmission line distance ratio is extensively investigated in this study. The results show that under the case of the wind, solar and hydropower ratio is 40:1:150, the optimal values for maximally reducing hydropower low frequency oscillation are finally determined as kp = 0.8, ki = 0.25 and kd = 0.5. Regarding a certain wind/solar/hydropower quota, it is a promising strategy to increase the solar-load transmission line in order to achieve the safe and stable operation of the hybrid system and a relatively excellent dynamic regulation capacity of the hydropower governor. The model, methods and results implemented in this study are exploited to markedly improve new knowledge applications, policy management, low carbon emissions and investment competitiveness of future energy systems.
Simulating Diurnal Variations of Water Temperature and Dissolved Oxygen in Shallow Minnesota Lakes
Authors: Tasnim Bushra , Jamily Jalil A. , Fang Xing , Zhou Yangen , Hayworth Joel S.
Published: July 2021

In shallow lakes, water quality is mostly affected by weather conditions and some ecological processes which vary throughout the day. To understand and model diurnal-nocturnal variations, a deterministic, one-dimensional hourly lake water quality model MINLAKE2018 was modified from daily MINLAKE2012, and applied to five shallow lakes in Minnesota to simulate water temperature and dissolved oxygen (DO) over multiple years. A maximum diurnal water temperature variation of 11.40 °C and DO variation of 5.63 mg/L were simulated. The root-mean-square errors (RMSEs) of simulated hourly surface temperatures in five lakes range from 1.19 to 1.95 °C when compared with hourly data over 4–8 years. The RMSEs of temperature and DO simulations from MINLAKE2018 decreased by 17.3% and 18.2%, respectively, and Nash-Sutcliffe efficiency increased by 10.3% and 66.7%, respectively; indicating the hourly model performs better in comparison to daily MINLAKE2012. The hourly model uses variable hourly wind speeds to determine the turbulent diffusion coefficient in the epilimnion and produces more hours of temperature and DO stratification including stratification that lasted several hours on some of the days. The hourly model includes direct solar radiation heating to the bottom sediment that decreases magnitude of heat flux from or to the sediment.
Analysis of Existing Equations for Calculating the Settling Velocity
Authors: Shankar M. Shiva , Pandey Manish , Shukla Anoop Kumar
Published: July 2021

The settling velocity of sediment is one of the essential parameters in studying freshwater reservoirs and transporting sediment in flowing water, mainly when the suspension is the dominant process. Hence, their quantitative measurements are crucial. An error during the prediction of the settling velocity may be increased by a factor of three or more in the estimation of the suspended load transport in the flowing water. Despite its significance, obtaining its real value in situ is practically impossible, and it is usually derived via laboratory tests or anticipated by empirical formulas. Numerous equations are available to calculate the settling velocity of the particle. However, it is exceedingly difficult to choose the best method when giving a specific solution for the same problem. Hence, a review of the existing equations is required. In this study, extensive data on settling velocity is collected from the literature, and previously proposed equations are analysed using graphical and statistical analysis.
A Continental Assessment of Reservoir Storage and Water Availability in South America
Authors: Paredes-Beltran Bolivar , Sordo-Ward Alvaro , de-Lama B. , Garrote Luis
Published: July 2021

This study presents the first continental assessment of water storage and its influence on the availability of water of the river systems of South America. Although hydraulic infrastructure has the potential to cause several impacts on river systems and the environment, their relevance in water resources systems is irrefutable. The human services that dams and reservoirs provide to society, e.g., hydroelectricity, water supply, irrigation, or flood control, are vital services that society requires to develop. Despite this fact, the interactions of dams and reservoirs in the river systems of South America have not been explored from a hydrological perspective. In this study, we present the first assessment of the potential effects of water storage at a basin scale in South America. For this purpose, first we present an analysis of the current conditions and the influence of water storage in the basins of the continent. Then, we estimate the potential water availability of each basin, to evaluate the role of water storage in the availability of water in the continent. Our findings indicate that the ‘Colorado’ and ‘Negro’ basins in Argentina are the most influenced by water storage in the continent. Moreover, our results suggest that reservoirs improve the potential water availability capacity, particularly in the southern basins of the continent. With this study, we expect to provide helpful insights about the current interactions of reservoirs with the river systems of the continent.
Certain Aspects of Termination of Employment Upon the Liquidation of an Organization
Authors: Sokolenko N. N. , Gerashchenko I. V.
Published: July 2021

In considering labour disputes, related to the termination of the employment contract at the initiative of the employer, including the liquidation of the organization, first and foremost, it must be considered that the employer must provide to the court the necessary evidence of the existence of a legitimate basis and compliance with the lawful procedure for dismissal, which as the authors have found out, is not always possible in practice because of legal uncertainties.
State civil service: questions relations between administrative and labor law
Authors: Grishkovets A. A.
Published: July 2021

The article analyzes the problems of correlation between administrative and labor law of Russia in regulating relations in the civil service, with consideration of the possibility of subsidiary application of the norms of labor legislation of the Russian Federation in regulating relations in the civil service. It is concluded that the state-service relations themselves are not identical with those related to the state civil service. In this regard, the prospects for the development of the civil service in order to further strengthen the public legal status of civil servants are outlined.
Practice of applying minimum wage legislation
Authors: Sagandykov M. S.
Published: July 2021

The article deals with the issue of the possibility of including compensatory and incentive payments into the minimum payment amount in the light of recent decisions of the Constitutional Court of the Russian Federation. On the basis of the analysis of these decisions, as well as the practice of courts of general jurisdiction of different levels, scientific literature, a number of conclusions are made, the essence of which is reduced to the necessity of changing the nature of the minimum wage, taking out all compensatory and incentive payments beyond its limits.
Internal labor regulations — the main local regulatory act of the organization
Authors: Petrov A. Ya.
Published: July 2021

Based on the analysis of labour legislation and judicial practice, the article considers the content of internal labour regulations as the main local normative act of the organization.
Dualism of the legal status of the head of the organization
Authors: Kulakova O. S.
Published: July 2021

The status of the head of a business company is a controversial legal category. The relevance of this issue is determined by the complexity of the nature of legal relations that develop at the intersection of labor and corporate law. The ambiguity of judicial practice in the qualification of the position of a person who is both a separate part of a legal entity and an employee makes it necessary to search for priority rules of law.
Issues of Labor Remuneration in the Conditions of Remote Work
Authors: Kozina E. V.
Published: July 2021

Recently, the number of works transferred to remote conditions has been increasing. In this regard, questions and disputes over wages will become more acute. A controversial issue of remuneration in remote work is the difficulty of recording the recording of the working time spent by the employee during the performance of his job function. Another problem for workers transferred to remote work conditions is the actual impossibility of performing part of their work duties. The consequence of this is the non-payment of the incentive part of the salary in whole or in part.
Effectiveness and timeliness of legislative measures to support workers and employers during the pandemic COVID-19 in the Socialist Republic of Viet Nam
Authors: Kabanov A. A. A.
Published: July 2021

The article examines the main measures that supplemented the legislation and the pandemic period, concludes that the main reason for the effectiveness of Viet Nam's labor law was the timely introduction and active use of a special portal by employees and employers and the urgent adoption of changes in the labor legislation of their country.
A Conceptual Approach to Forming a Transport and Logistics Cluster as a Component of the Region’s Innovative Infrastructure (on the Example of Prydniprovsky Economic Region of Ukraine)
Authors: Liashenko Viacheslav , Ivanov Sergey , Trushkina Nataliia
Published: July 2021

The analysis of the dynamics of the regional transport and logistics system of the Prydniprovsky economic region revealed many barriers to its effective functioning, which were divided into 10 groups: political, institutional, innovative, investment and financial, information, environmental, tariff, infrastructure, customs, and logistics. The forecast estimation of the indicators characterizing the development of the regional transport and logistic system in the Prydniprovsky economic region by using economic and mathematical tools was carried out, and on this basis tendencies of its functioning were revealed. It should be noted that forecast estimates should be considered forecasts-warnings. That is, provided that the insignificant level of labor productivity is maintained, as well as its reduction, the low return on capital investments in the coming years can significantly reduce the volume of transport (rail and road) in the Prydniprovsky economic region. Based on the regional development strategies of Dnipropetrovsk, Zaporizhzhia and Kirovohrad regions generalized, their shortcomings in creating a transport and logistics cluster were identified. In order to transform the regional innovation ecosystem, a conceptual approach to forming the transport and logistics cluster as an element of innovation infrastructure based on reasonable specialization was substantiated. It was proved that this structure should take the form of a partnership of business structures, research institutions, higher education institutions, institutions of logistics and innovation infrastructure, and government agencies. The structural scheme of interaction between the transport and logistics cluster and the innovation ecosystem was proposed to achieve the strategic goal of "Innovative development of the region on the basis of smart specialization" while implementing the strategic documents for the period till 2027. It was established that the development and implementation of basic conceptual provisions for forming a transport and logistics cluster would create appropriate conditions for increasing the volume and quality of transport and logistics services, for intensifying innovative development and implementing a qualitatively new regional pattern of sustainable development of the Prydniprovsky economic region, which must meet modern requirements for managing economic systems.
Organization of Aviation Enterprises’ Interaction Based on the Digital Platform
Authors: Molchanova Kateryna
Published: July 2021

The article considers the approach to digital transformation of the aviation industry in terms of organizing the interaction of supply chain participants involving air transport based on the digital platform. Digital transformation is considered not only as a tool of information interaction, but also as a business model that creates value by uniting consumers and producers of goods and services. There was performed a statistical analysis of indicators characterizing the state of the global aviation market and that of Ukraine in particular, of the global crisis impact caused by the COVID-19 pandemic on air transport and changes in the field of passenger and freight transport; there were analyzed the possible ways of overcoming the consequences of the crisis for airlines and airports and the use of digital technologies in developing anti-crisis strategies. The necessity of forming a united information space in the supply chain to ensure the rapid exchange of information between cooperating transport hubs and government agencies, including the exchange of information on the management of production and commercial activities of transport enterprises was highlighted. The role of air transport in servicing global supply chains was also emphasized, as it offers highly integrated and comprehensive fast delivery with safe, reliable, convenient and highly efficient services. There was proposed a scheme of information interaction among supply chain participants involving air transport based on the digital platform in the context of united information space. The use of the digital platform as a tool for organizing interaction was justified, as this technology provides massive opportunities to achieve increased efficiency not only of individual units, but also of the entire supply chain.