bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic Incentives for Environmental Investment in Modern Russia
Authors: Kormishkina Ludmila Aleksandrovna , Kormishkin Evgenii Danilovich , Sausheva Oksana Sergeevna , Koloskov Dmitrii Aleksandrovich
Published: October 2021

This paper is relevant due to the critical need for changing the consumption-oriented economic growth model to an investment one for the long-term sustainable development of Russia, considering global environmental challenges. Environmental investments (EIs), responsible and transformative, are positioned as the growth driver. The study aims to assess the mechanism of environmental investment (EI) in modern Russia, determine limitations, and form the resource-saving principles adequate to the latest challenges. The developed regression models of EI resource potential indicate the inability in the current institutional environment to provide the amount of financing required to form a green economy in Russia. This work justifies the need to establish an integrated mechanism for EI economic incentives to increase their amount in the private sector and obtain socio-economic benefits (natural capital maintenance, efficient resource use, and poverty and unemployment reduction). Based on the world’s best practice analysis of state support for EI market instruments, it sets out proposals to establish this mechanism in Russia and confirms the need to create conditions in which it is more profitable for economic agents to invest in reducing their ecological footprint. This paper proves that EIs promotion should combine positive and negative motivation, engagement, and responsibilities.
Performance Assessment and Working Fluid Selection for Novel Integrated Vapor Compression Cycle and Organic Rankine Cycle for Ultra Low Grade Waste Heat Recovery
Authors: Asim Muhammad , Kashif Faiza , Umer Jamal , Alvi Jahan Zeb , Imran Muhammad , Khan Sheheryar , Zia Abdul Wasy , Leung Michael K. H.
Published: October 2021

This paper presents the performance assessment and working fluid selection for a novel integrated vapor compression cycle-organic Rankine cycle system (i-VCC-ORC), which recovers ultra-low-temperature waste heat rejected (50 °C) by the condenser of a vapor compression cycle (VCC). The analyses are carried out for a vapor compression cycle of a refrigeration capacity (heat input) of 35kW along with the component sizing of the organic Rankine cycle (ORC). The effects of the operational parameters on integrated system performance were investigated. The integrated system performance is estimated in terms of net COP, cycle thermal efficiency and exergy efficiency by completely utilizing and recovering the heat rejected by the condenser of the VCC system. R600a-R141b with COPnet (3.54) and ORC thermal efficiency (3.05%) is found to be the most suitable VCC-ORC working fluid pair. The integration of the vapor compression refrigeration cycle with the organic Rankine cycle increases the COP of the system by 12.5% as compared to the standalone COP of the vapor compression system. Moreover, the sensitivity analysis results show that there exists an optimum operating condition that maximizes the thermal performance of the integrated system.
Advanced Fuzzy 12 DTC Control of Doubly Fed Induction Generator for Optimal Power Extraction in Wind Turbine System under Random Wind Conditions
Authors: Sahri Younes , Tamalouzt Salah , Lalouni Belaid Sofia , Bacha Seddik , Ullah Nasim , Ahamdi Ahmad Aziz Al , Alzaed Ali Nasser
Published: October 2021

A wind turbine (WT)-based doubly fed induction generator (DFIG) is the most often used generator in the wind conversion system market due to its advantages such as the ability of operating under variable wind speed and its high performance. However, nonlinear dynamical and parameter uncertainties of the DFIG make the controller design of this kind of system a challenging work. Thus, in this study, a novel control strategy was proposed to design the desired system dynamics, to highlight the efficacy of the proposed system, and to improve the performance of the closed-loop system. The proposed controller combines the twelve-sector direct torque control (12-DTC) and the fuzzy controller with modified rules to solve the limitations and shortcomings of the usual methods for the WT-DFIG system. All operation modes, successively and continually, were considered to reflect the true operation of WT-DFIG system subject to random wind speeds. The aims of this work was to ensure an optimal operation of the wind generator, extracting maximum power in the zone II of the WT characteristic, and limiting this power in its maximum value in the case (zone III), to transmit the power generated by the DFIG to the grid-side with minimum losses in the disturbances related to DFIG. Extensive numerical simulations were performed under MATALB/Simulink, where the proposed fuzzy twelve direct torque control (F12-DTC) was compared with conventional nonlinear controls: conventional DTC (C-DTC) and 12-DTC. The simulation results demonstrated clearly that the proposed one had the highest performance and robustness, with a significant reduction in rotor flux and electromagnetic torque ripples and better-generated power quality with low currents’ THD over the conventional strategies (C-DTC and 12-DTC).
Economic Policy Uncertainty, Financial Expenditure and Energy Poverty: Evidence Based on a Panel Threshold Model
Authors: Che Xiahui , Jiang Minxing
Published: October 2021

The COVID-19 pandemic has forced people to pay more attention to the negative impacts of economic policy uncertainty on energy poverty. Meanwhile, through financial expenditure, governments might play a critical role in energy poverty alleviation, but there is little focus on this factor in the literature. We employ a panel threshold model to investigate the threshold effect of economic policy uncertainty between financial expenditure and energy poverty. This model can keenly explore the time-varying characteristics of financial expenditure. In order to control the endogenous influence, the estimators of the panel least square method are used to replace the corresponding endogenous variables. We find that financial expenditure has a significant positive effect on energy poverty alleviation, and that the positive effect has the threshold characteristic of economic policy uncertainty. With the rise in economic policy uncertainty, the positive effect of financial expenditure on energy poverty is continuously enhanced. Furthermore, we find that financial expenditure plays a more significant role in alleviating energy poverty in emerging economies than it does in developed economies.
Research on Precipitation Forecast Based on LSTM–CP Combined Model
Authors: Guo Yan , Tang Wei , Hou Guanghua , Pan Fei , Wang Yubo , Wang Wei
Published: October 2021

The tremendous progress made in the field of deep learning allows us to accurately predict precipitation and avoid major and long-term disruptions to the entire socio-economic system caused by floods. This paper presents an LSTM–CP combined model formed by the Long Short-Term Memory (LSTM) network and Chebyshev polynomial (CP) as applied to the precipitation forecast of Yibin City. Firstly, the data are fed into the LSTM network to extract the time-series features. Then, the sequence features obtained are input into the BP (Back Propagation) neural network with CP as the excitation function. Finally, the prediction results are obtained. By theoretical analysis and experimental comparison, the LSTM–CP combined model proposed in this paper has fewer parameters, shorter running time, and relatively smaller prediction error than the LSTM network. Meanwhile, compared with the SVR model, ARIMA model, and MLP model, the prediction accuracy of the LSTM–CP combination model is significantly improved, which can aid relevant departments in making disaster response measures in advance to reduce disaster losses and promote sustainable development by providing them data support.
Public Health and International Obligations of States: The Case of COVID-19 on Cruise Ships
Authors: Liu Chenhong
Published: October 2021

Against the backdrop of the COVID-19 outbreak onboard the cruise ship Diamond Princess, both the flag State and the port State should act according to international obligations during the sailing stage, quarantine period after ships’ berthing, and the time when the quarantine period expires. However, the potential danger of the absence of a “genuine link” between the cruise shipowners and the flag State, the lack of coordination of jurisdiction in different sea areas and between different States, and also the lack of special or systematic regulations for infection prevention and control (IPC) at sea and for cruise ships increase the risk of a State’s breach of international obligations. Therefore, it is deemed necessary to improve the responsive measures in international law. This paper, after review and analysis, sheds light on various recommendations on how to improve the responsive measures in international law, including (i) strengthening of the jurisdiction of the flag State, (ii) establishment of a special international cooperation mechanism with an alliance between the WHO and the IMO, and (iii) construction of an IPC mechanism for home ports of cruise ships.
Indigenous Pest Management Practices of Indian Hill Farmers: Introspecting Their Rationale and Communication Pattern for Secure Ecosystems
Authors: Rathore Surya , Chandola Manish , Raghuvanshi Rupan , Kaur Manmeet , Singh Kundan Veer
Published: October 2021

Indigenous technical knowledge derived from traditional wisdom is an asset of farmers in developing countries. To ensure the continuity of these practices for future generations, we need to understand the scientific rationality and their communication patterns, and then document them. This study aimed to document the indigenous pest management practices, test their scientific rationality, and determine their communication pattern among the farmers. A total of 120 farmers from district Bageshwar in Uttarakhand, India, were selected through the simple random sampling method. Interviews and focussed group discussions were used to collect data. Out of a total of 32 documented indigenous practices, 27 were found to be rational by the scientists. Neighbours ranked first as the source of information, followed by friends and relatives. Knowledge related to managing pests through indigenous methods was shared by the farmers, mainly in temples. They learned the practical application of these indigenous practices during childhood while working with parents in the fields, followed by observing their friends and relatives. The indigenous technical knowledge should be conserved and combined with the scientific cognizance for sustainable agriculture. Next- generation farmers need to be motivated to adopt these practices.
The Effect Evaluation of China’s Energy-Consuming Right Trading Policy: Empirical Analysis Based on PSM-DID
Authors: Wang Zhong , Wu Mingyu , Li Shixiang , Wang Changji
Published: October 2021

Identifying the policy effect of Energy-Consuming Right Trading (ECRT), clarifying its mechanism of energy conservation and consumption reduction, is beneficial to realize the win–win situation of economic growth and emission reduction in China. This study first builds a Propensity Score Matching–Difference-in-Differences (PSM-DID) model and empirically tests the impact of Energy-Consuming Right Trading policy on energy intensity in pilot areas based on inter-provincial panel data from 2010 to 2019. Then the policy mechanism was analyzed by further regression, and the spatial effects of the policy were explored by the Spatial Difference-in-Differences (SDID) model. The results show that: (1) The policy can reduce energy intensity by 6.4% to 10.2% in the pilot area. (2) The policy mainly achieves energy consumption reduction by optimizing the industrial structure and promoting scientific and technological input, while the resource tax intensity and the proportion of coal consumption also have synergistic and hindering effects on the policy. (3) There is a significant spatial spillover effect of the policy; it can reduce the energy intensity of the adjacent areas of the pilot by 5.3% and the areas with a high economic association with the pilot by 12%. The conclusion is that China’s Energy-Consuming Right Trading policy can effectively control energy consumption, and the policy shows an excellent positive external effect, worth nationwide implementation. Finally, some policy suggestions are put forward according to the results of the empirical analysis.
Comparison Study on the Performance of a Novel and Traditional Energy Piles by Laboratory Tests
Authors: Bao Xiaohua , Qi Xuedong , Cui Hongzhi , Zou Jinping , Xiao Xiong
Published: October 2021

Phase change material (PCM) is a substance that can absorb or release sufficient latent heat at phase transition. By encapsulating phase change paraffin in hollow steel balls in the concrete, an energy pile with PCM was innovatively produced to improve energy efficiency for the ground heat pumping system. Laboratory tests were carried out on both PCM energy pile and traditional concrete pile to evaluate the thermo mechanical performance. Two piles were heated and cooled through inside tubes at a constant flow rate. The laboratory tests on the two piles were symmetrical for the two horizontal directions in geometry, and heat transfer process follows conservation laws of energy. The temperature response of the pile and soil, internal strain, pile displacement, pore pressure, and soil pressure under heating-cooling cycles were examined. Compared with the traditional concrete pile, the PCM energy pile can effectively reduce the surrounding soil temperature. The use of PCM in the pile can improve the capacity of heat storage and make the pile more effective in heat exchange. Non-uniform thermal strain and accumulations of heat and irrecoverable displacement were observed in the repeated heating-cooling process. The study can provide references for the practical implication of PCM energy piles.
Double Integral of the Product of the Exponential of an Exponential Function and a Polynomial Expressed in Terms of the Lerch Function
Authors: Reynolds Robert , Stauffer Allan
Published: October 2021

In this work, the authors use their contour integral method to derive an application of the Fourier integral theorem given by ∫−∞∞∫−∞∞emx−my−ex−ey+y(log(a)+x−y)kdxdy in terms of the Lerch function. This integral formula is then used to derive closed solutions in terms of fundamental constants and special functions. Almost all Lerch functions have an asymmetrical zero distribution. There are some useful results relating double integrals of certain kinds of functions to ordinary integrals for which we know no general reference. Thus, a table of integral pairs is given for interested readers. All of the results in this work are new.
Exact Closed-Form Solutions of the Motion in Non-Inertial Reference Frames, Using the Properties of Lie Groups SO3 and SE3
Authors: Condurache Daniel , Șfartz Eugen
Published: October 2021

The paper offers a general symbolic method to study the motion in a non-inertial reference frame. In order to achieve this, we use the algebraic and geometric properties of the Lie group of special orthogonal tensors, SO3, and the Lie group of the rigid body displacements, SE3. We obtain a simplified form of the initial value problem that models the non-inertial motion using a tensor instrument introduced in this paper. Thus, the study of the motion in a non-inertial reference frame is transferred into the study of a classical motion in an inertial reference frame. The applications of this method refer to solving the relative motion problem and deriving the straightforward solution to classical theoretical mechanics problems. The motion in a uniform gravitational force field in a rotating reference frame, the motion of a charged particle in non-stationary electric and magnetic fields, the exact solution of the relative rigid body motion in the non-inertial reference frame are studied. Using this symbolic method in studying the motion in a non-inertial reference frame reduces the number of computations. In addition, it offers, in some essential particular cases, exact closed-form coordinate-free analytical solutions.
Mobile Expert System: Exploring Context-Aware Machine Learning Rules for Personalized Decision-Making in Mobile Applications
Authors: Sarker Iqbal H. , Khan Asif Irshad , Abushark Yoosef B. , Alsolami Fawaz
Published: October 2021

Expert systems, a form of artificial intelligence (AI), are typically designed to solve many real-world problems by reasoning through knowledge, which is primarily represented as IF–THEN rules, with the information acquired from humans or domain experts. However, to assume such rules for personalized decision-making in an intelligent, context-aware mobile application is a challenging issue. The reason is that different mobile users may behave differently in various day-to-day situations, i.e., not identical, and thus the rules for personalized services must be reflected according to their symmetrical or asymmetrical behavioral activities. Therefore, our key focus is to solve this issue through adding personalized decision-making intelligence to develop powerful mobile applications to assist the end-users. To achieve our goal, in this paper, we explore on “Mobile Expert System”, where we take into account machine-learning rules as knowledge-base rather than traditional handcrafted static rules. Thus, the concept of a mobile expert system enables the computing and decision-making processes more actionable and intelligent than traditional ones in the domain of mobile analytics and applications. Our experiment section shows that the context-aware machine learning rules discovered from users’ mobile phone data can contribute in building a mobile expert system to solve a particular problem, through making personalized decisions in various context-aware test cases.
The Unruh Effect in Slow Motion
Authors: Vriend Silas , Grimmer Daniel , Martín-Martínez Eduardo
Published: October 2021

We show under what conditions an accelerated detector (e.g., an atom/ion/molecule) thermalizes while interacting with the vacuum state of a quantum field in a setup where the detector’s acceleration alternates sign across multiple optical cavities. We show (non-perturbatively) in what regimes the probe ‘forgets’ that it is traversing cavities and thermalizes to a temperature proportional to its acceleration, the same as it would in free space. Then we analyze in detail how this thermalization relates to the renowned Unruh effect. Finally, we use these results to propose an experimental testbed for the direct detection of the Unruh effect at relatively low probe speeds and accelerations, potentially orders of magnitude below previous proposals.
Bilateral Strength Asymmetry in Elite Youth Soccer Players: Differences between Age Categories
Authors: Kalata Maros , Hank Mikulas , Bujnovsky David , Michalek Jakub , Varjan Matej , Kunzmann Egon , Zahalka Frantisek , Maly Tomas
Published: October 2021

The strength asymmetry of athletes as a negative health and performance factor is increasingly being researched in sports with a high load on the dominant limb when some specific unilateral movements, such as passing, jumping, and tackling, are required. This study aimed to determine the level of isokinetic strength bilateral asymmetry (BA) among knee extensors (KEs) and knee flexors (KFs) of elite youth soccer players. The sample (n = 87) consisted of three age categories of under 13 (U13), under 15 (U15), and under 17 (U17) years old. Isokinetic dynamometry was used to obtain the maximum peak torque of the KEs and KFs in the dominant and non-dominant lower limbs during concentric muscle contraction. The analysis revealed significantly lower values (p < 0.05) of BA in KEs in U17 than in younger categories, U13 and U15, and higher values (p < 0.05) of BA in KFs in the U15 category than in the U17category. The majority of the players in the U15 category (68%) reached KFs BA higher than 10% in comparison with U13 players (50%) and U17 players (28% of players) (p < 0.05). Our results showed a significant effect of age category on BA levels in young soccer players. High incidences of increased BA in the lower limbs occurred in the younger categories (U13, U15) and subsequently decreased in the later adolescent stages.
A Double Logarithmic Transform Involving the Exponential and Polynomial Functions Expressed in Terms of the Hurwitz–Lerch Zeta Function
Authors: Reynolds Robert , Stauffer Allan
Published: October 2021

The object of this paper is to derive a double integral in terms of the Hurwitz–Lerch zeta function. Almost all Hurwitz–Lerch zeta functions have an asymmetrical zero-distribution. Special cases are evaluated in terms of fundamental constants. All the results in this work are new.
Quantum Game Application to Recovery Problem in Mobile Database
Authors: Madbouly Magda M. , Mokhtar Yasser F. , Darwish Saad M.
Published: October 2021

Mobile Computing (MC) is a relatively new concept in the world of distributed computing that is rapidly gaining traction. Due to the dynamic nature of mobility and the limited bandwidth available on wireless networks, this new computing environment for mobile devices presents significant challenges in terms of fault-tolerant system development. As a consequence, traditional fault-tolerance techniques are inherently inapplicable to these systems. External circumstances often expose mobile systems to failures in communication or data storage. In this article, a quantum game theory-based recovery model is proposed in the case of a mobile host’s failure. Several of the state-of-the-art recovery protocols are selected and analyzed in order to identify the most important variables influencing the recovery mechanism, such as the number of processes, the time needed to send messages, and the number of messages logged-in time. Quantum game theory is then adapted to select the optimal recovery method for the given environment variables using the proposed utility matrix of three players. Game theory is the study of mathematical models of situations in which intelligent rational decision-makers face conflicting interests (alternative recovery procedures). The purpose of this study is to present an adaptive algorithm based on quantum game theory for selecting the most efficient context-aware computing recovery procedure. The transition from a classical to a quantum domain is accomplished in the proposed model by treating strategies as a Hilbert space rather than a discrete set and then allowing for the existence of linear superpositions between classical strategies; this naturally increases the number of possible strategic choices available to each player from a numerable to a continuous set. Numerical data are provided to demonstrate feasibility.
Implementation of a Technique Based on Hounsfield Units and Hounsfield Density to Determine Kidney Stone Composition
Authors: Rodríguez-Plata Irvin Tadeo , Medina-Escobedo Martha , Basulto-Martínez Mario , Avila-Nava Azalia , Gutiérrez-Solis Ana Ligia , Méndez-Domínguez Nina , Lugo Roberto
Published: October 2021

Hounsfield units (HU) are a measure of radiodensity, related to the density of a tissue and the composition of kidney stones. Hounsfield density is what is related to the composition of kidney stones. In the standard acquisition method, these measures are arbitrary and dependent on the operator. This study describes the implementation of a technique based on the HU and Hounsfield density to predict the stone compositions of patients with nephrolithiasis. By conventional percutaneous nephrolithotomy, thirty kidney stone samples corresponding to the cortex, middle, and nucleus were obtained. The HU were obtained by CT scanning with a systematic grid. Hounsfield density was calculated as the HU value divided by the stone’s greatest diameter (HU/mm). With that method and after analyzing the samples by IR-spectroscopy, anhydrous uric acid and ammonium magnesium phosphate were identified as the compounds of kidney stones. Additionally, anhydrous uric acid, magnesium ammonium phosphate, and calcium oxalate monohydrate were identified via Hounsfield density calculation. The study identified HU ranges for stone compounds using a systematic technique that avoids bias in its analysis. In addition, this work could contribute to the timely diagnosis and development of personalized therapies for patients with this pathology.
Salinity Affects Saxitoxins (STXs) Toxicity in the Dinoflagellate Alexandrium pacificum, with Low Transcription of SXT-Biosynthesis Genes sxtA4 and sxtG
Authors: Bui Quynh Thi Nhu , Kim Hansol , Park Hyunjun , Ki Jang-Seu
Published: October 2021

Salinity is an important factor for regulating metabolic processes in aquatic organisms; however, its effects on toxicity and STX biosynthesis gene responses in dinoflagellates require further elucidation. Herein, we evaluated the physiological responses, toxin production, and expression levels of two STX synthesis core genes, sxtA4 and sxtG, in the dinoflagellate Alexandrium pacificum Alex05 under different salinities (20, 25, 30, 35, and 40 psu). Optimal growth was observed at 30 psu (0.12 cell division/d), but cell growth significantly decreased at 20 psu and was irregular at 25 and 40 psu. The cell size increased at lower salinities, with the highest size of 31.5 µm at 20 psu. STXs eq was highest (35.8 fmol/cell) in the exponential phase at 30 psu. GTX4 and C2 were predominant at that time but were replaced by GTX1 and NeoSTX in the stationary phase. However, sxtA4 and sxtG mRNAs were induced, and their patterns were similar in all tested conditions. PCA showed that gene transcriptional levels were not correlated with toxin contents and salinity. These results suggest that A. pacificum may produce the highest amount of toxins at optimal salinity, but sxtA4 and sxtG may be only minimally affected by salinity, even under high salinity stress.
Prioritization of Mycotoxins Based on Their Genotoxic Potential with an In Silico-In Vitro Strategy
Authors: Alonso-Jauregui Maria , Font María , González-Peñas Elena , López de Cerain Adela , Vettorazzi Ariane
Published: October 2021

Humans are widely exposed to a great variety of mycotoxins and their mixtures. Therefore, it is important to design strategies that allow prioritizing mycotoxins based on their toxic potential in a time and cost-effective manner. A strategy combining in silico tools (Phase 1), including an expert knowledge-based (DEREK Nexus®, Lhasa Limited, Leeds, UK) and a statistical-based platform (VEGA QSAR©, Mario Negri Institute, Milan, Italy), followed by the in vitro SOS/umu test (Phase 2), was applied to a set of 12 mycotoxins clustered according to their structure into three groups. Phase 1 allowed us to clearly classify group 1 (aflatoxin and sterigmatocystin) as mutagenic and group 3 (ochratoxin A, zearalenone and fumonisin B1) as non-mutagenic. For group 2 (trichothecenes), contradictory conclusions were obtained between the two in silico tools, being out of the applicability domain of many models. Phase 2 confirmed the results obtained in the previous phase for groups 1 and 3. It also provided extra information regarding the role of metabolic activation in aflatoxin B1 and sterigmatocystin mutagenicity. Regarding group 2, equivocal results were obtained in few experiments; however, the group was finally classified as non-mutagenic. The strategy used correlated with the published Ames tests, which detect point mutations. Few alerts for chromosome aberrations could be detected. The SOS/umu test appeared as a good screening test for mutagenicity that can be used in the absence and presence of metabolic activation and independently of Phase 1, although the in silico–in vitro combination gave more information for decision making.
Passage Number-Induced Replicative Senescence Modulates the Endothelial Cell Response to Protein-Bound Uremic Toxins
Authors: Guerrero Fatima , Carmona Andres , Jimenez Maria Jose , Obrero Teresa , Pulido Victoria , Moreno Juan Antonio , Soriano Sagrario , Martín-Malo Alejandro , Aljama Pedro
Published: October 2021

Endothelial aging may be induced early in pathological situations. The uremic toxins indoxyl sulfate (IS) and p-cresol (PC) accumulate in the plasma of chronic kidney disease (CKD) patients, causing accelerated endothelial aging, increased cardiovascular events and mortality. However, the mechanisms by which uremic toxins exert their deleterious effects on endothelial aging are not yet fully known. Thus, the aim of the present study is to determine the effects of IS and PC on endothelial damage and early senescence in cultured human umbilical vein endothelial cells (HUVECs). Hence, we establish an in vitro model of endothelial damage mediated by different passages of HUVECs and stimulated with different concentrations of IS and PC to evaluate functional effects on the vascular endothelium. We observe that cell passage-induced senescence is associated with apoptosis, ROS production and decreased endothelial proliferative capacity. Similarly, we observe that IS and PC cause premature aging in a dose-dependent manner, altering HUVECs’ regenerative capacity, and decreasing their cell migration and potential to form vascular structures in vitro. In conclusion, IS and PC cause accelerated aging in HUVECs, thus contributing to endothelial dysfunction associated with CKD progression.
Tetrodotoxins in French Bivalve Mollusks—Analytical Methodology, Environmental Dynamics and Screening of Bacterial Strain Collections
Authors: Réveillon Damien , Savar Véronique , Schaefer Estelle , Chevé Julien , Halm-Lemeille Marie-Pierre , Hervio-Heath Dominique , Travers Marie-Agnès , Abadie Eric , Rolland Jean-Luc , Hess Philipp
Published: October 2021

Tetrodotoxins (TTXs) are potentially lethal paralytic toxins that have been identified in European shellfish over recent years. Risk assessment has suggested comparatively low levels (44 µg TTX-equivalent/kg) but stresses the lack of data on occurrence. Both bacteria and dinoflagellates were suggested as possible biogenic sources, either from an endogenous or exogenous origin. We thus investigated TTXs in (i) 98 shellfish samples and (ii) 122 bacterial strains, isolated from French environments. We optimized a method based on mass spectrometry, using a single extraction step followed by ultrafiltration without Solid Phase Extraction and matrix-matched calibration for both shellfish and bacterial matrix. Limits of detection and quantification were 6.3 and 12.5 µg/kg for shellfish and 5.0 and 10 µg/kg for bacterial matrix, respectively. Even though bacterial matrix resulted in signal enhancement, no TTX analog was detected in any strain. Bivalves (either Crassostrea gigas or Ruditapes philippinarum) were surveyed in six French production areas over 2.5–3 month periods (2018–2019). Concentrations of TTX ranged from ‘not detected’ to a maximum of 32 µg/kg (Bay of Brest, 17 June 2019), with events lasting 2 weeks at maximum. While these results are in line with previous studies, they provide new data of TTX occurrence and confirm that the link between bacteria, bivalves and TTX is complex.
Experimental Study on the Status of Maize Mycotoxin Production in Farmers’ Grain Storage Silos in Northeastern China
Authors: Zhang Jinsong , Xu Yan , Hu Taogang , Sun Changpo , Wu Wenfu
Published: October 2021

The scientific rationality of farmers’ grain storage technology and equipment is crucial for the biosecurity of grain in the main grain-producing areas represented by Northeast China. In this paper, four farmer grain storage mock silos of different widths were used as a means to track an experimental cycle of grain storage. The absolute water potential of corn in all four silos at the beginning of the experiment was greater than the absolute water potential of air, prompting moisture migration from the grain interior to the air and down to about 14%. Moisture was influenced by wind direction, and moisture decreased faster with better ventilation on both sides of the grain silos. Therefore, grain silo width has a significant effect on the drying effect under naturally ventilated conditions of maize ears. This research focused on the determination and assessment of mycotoxin contamination under farmers’ storage grain conditions and analyzed the effect of silo structure on the distribution of mycotoxin contamination. When the width was too large, areas of high mycotoxin infection existed in the middle of the grain silo, and ventilation and tipping could be used to reduce the risk of toxin production. This study proved that reasonable farmer grain storage techniques and devices in Northeast China can effectively protect grain from mycotoxin contamination.
Kidney Transplantation during the SARS-CoV-2 Pandemic in Israel: Experience from a Large-Volume Center
Authors: Gravetz Aviad , Tennak Vladimir , Mezhebovsky Vadym , Gurevich Michael , Eisner Sigal , Nesher Eviatar
Published: October 2021

Coronavirus disease 2019 (COVID-19) has affected tens of millions of people globally since it was declared a pandemic by the World Health Organization on 11 March 2020. Since its outbreak in December 2019, the ongoing coronavirus COVID-19 pandemic has led to global social, economic and healthcare crises affecting millions of people and causing the death of hundreds of thousands of people worldwide. As with other fields of healthcare, the pandemic with its heavy workload imposed on hospital services and personnel significantly affected solid organ transplantation. Concerns for potential exposure to the virus and its related severe acute respiratory syndrome coronavirus type 2 (SARS-CoV2) have profoundly altered the process of organ donation and recovery, acceptance of organ offers, management of potential recipients and living donors, and above all transplanted and immunosuppressed patients. All those issues required prompt implementation of new practice measures and guidelines as well as continuous adaptations to the fluid and rapidly changing situation. Herein we describe a single transplant center experience with kidney transplantation during the COVID-19 pandemic; we review the national and institutional measures and restrictions undertaken in different phases of the ongoing event as well as the outcomes.
Frame-Dragging: Meaning, Myths, and Misconceptions
Authors: Costa L. , Natário José
Published: October 2021

Originally introduced in connection with general relativistic Coriolis forces, the term frame-dragging is associated today with a plethora of effects related to the off-diagonal element of the metric tensor. It is also frequently the subject of misconceptions leading to incorrect predictions, even of nonexistent effects. We show that there are three different levels of frame-dragging corresponding to three distinct gravitomagnetic objects: gravitomagnetic potential 1-form, field, and tidal tensor, whose effects are independent, and sometimes opposing. It is seen that, from the two analogies commonly employed, the analogy with magnetism holds strong where it applies, whereas the fluid-dragging analogy (albeit of some use, qualitatively, in the first level) is, in general, misleading. Common misconceptions (such as viscous-type “body-dragging”) are debunked. Applications considered include rotating cylinders (Lewis–Weyl metrics), Kerr, Kerr–Newman and Kerr–dS spacetimes, black holes surrounded by disks/rings, and binary systems.
Asymptotic Safety: Swampland or Wonderland?
Authors: Basile Ivano , Platania Alessia
Published: October 2021

We investigate the consequences of combining swampland conjectures with the requirement of asymptotic safety. To this end, we explore the infrared regime of asymptotically safe gravity in the quadratic one-loop approximation, and we identify the hypersurface spanned by the endpoints of asymptotically safe renormalization group trajectories. These comprise the allowed values of higher-derivative couplings, as well as standard logarithmic form factors. We determine the intersection of this hypersurface with the regions of parameter space allowed by the weak-gravity conjecture, the swampland de Sitter conjecture, and the trans-Planckian censorship conjecture. The latter two depend on some order-one constants, for generic values of which we show that the overlap region is a proper subspace of the asymptotically safe hypersurface. Moreover, the latter lies inside the region allowed by the weak gravity conjecture assuming electromagnetic duality. Our results suggest a non-trivial interplay between the consistency conditions stemming from ultraviolet completeness of the renormalization group flow, black hole physics, and cosmology.
The Biogenesis of Dengue Virus Replication Organelles Requires the ATPase Activity of Valosin-Containing Protein
Authors: Mazeaud Clément , Anton Anaïs , Pahmeier Felix , Sow Aïssatou Aïcha , Cerikan Berati , Freppel Wesley , Cortese Mirko , Bartenschlager Ralf , Chatel-Chaix Laurent
Published: October 2021

The dengue virus (DENV) causes the most prevalent arthropod-borne viral disease worldwide. While its incidence is increasing in many countries, there is no approved antiviral therapy currently available. In infected cells, the DENV induces extensive morphological alterations of the endoplasmic reticulum (ER) to generate viral replication organelles (vRO), which include convoluted membranes (CM) and vesicle packets (VP) hosting viral RNA replication. The viral non-structural protein NS4B localizes to vROs and is absolutely required for viral replication through poorly defined mechanisms, which might involve cellular protein partners. Previous interactomic studies identified the ATPase valosin-containing protein (VCP) as a DENV NS4B-interacting host factor in infected cells. Using both pharmacological and dominant-negative inhibition approaches, we show, in this study, that VCP ATPase activity is required for efficient DENV replication. VCP associates with NS4B when expressed in the absence of other viral proteins while in infected cells, both proteins colocalize within large DENV-induced cytoplasmic structures previously demonstrated to be CMs. Consistently, VCP inhibition dramatically reduces the abundance of DENV CMs in infected cells. Most importantly, using a recently reported replication-independent plasmid-based vRO induction system, we show that de novo VP biogenesis is dependent on VCP ATPase activity. Overall, our data demonstrate that VCP ATPase activity is required for vRO morphogenesis and/or stability. Considering that VCP was shown to be required for the replication of other flaviviruses, our results argue that VCP is a pan-flaviviral host dependency factor. Given that new generation VCP-targeting drugs are currently evaluated in clinical trials for cancer treatment, VCP may constitute an attractive broad-spectrum antiviral target in drug repurposing approaches.
A Perspective on Nanotechnology and COVID-19 Vaccine Research and Production in South Africa
Authors: Dube Admire , Egieyeh Samuel , Balogun Mohammed
Published: October 2021

Advances in nanotechnology have enabled the development of a new generation of vaccines, which are playing a critical role in the global control of the COVID-19 pandemic and the return to normalcy. Vaccine development has been conducted, by and large, by countries in the global north. South Africa, as a major emerging economy, has made extensive investments in nanotechnology and bioinformatics and has the expertise and resources in vaccine development and manufacturing. This has been built at a national level through decades of investment. In this perspective article, we provide a synopsis of the investments made in nanotechnology and highlight how these could support innovation, research, and development for vaccines for this disease. We also discuss the application of bioinformatics tools to support rapid and cost-effective vaccine development and make recommendations for future research and development in this area to support future health challenges.
The Role of RASs /RVs in the Current Management of HCV
Authors: Malandris Konstantinos , Kalopitas Georgios , Theocharidou Eleni , Germanidis Georgios
Published: October 2021

The approval of combination therapies with direct-acting antiviral (DAA) regimens has led to significant progress in the field of hepatitis C virus (HCV) treatment. Although most patients treated with these agents achieve a virological cure, resistance to DAAs is a major issue. The rapid emergence of resistance-associated substitutions (RASs), in particular in the context of incomplete drug pressure, has an impact on sustained virological response (SVR) rates. Several RASs in NS3, NS5A and NS5B have been linked with reduced susceptibility to DAAs. RAS vary based on HCV characteristics and the different drug classes. DAA-resistant HCV variant haplotypes (RVs) are dominant in cases of virological failure. Viruses with resistance to NS3-4A protease inhibitors are only detected in the peripheral blood in a time frame ranging from weeks to months following completion of treatment, whereas NS5A inhibitor-resistant viruses may persist for years. Novel agents have been developed that demonstrate promising results in DAA-experienced patients. The recent approval of broad-spectrum drug combinations with a high genetic barrier to resistance and antiviral potency may overcome the problem of resistance.
COVID-19 in 2021
Authors: Lundstrom Kenneth , Aljabali Alaa A. A.
Published: October 2021

The Special Issue on Vaccines and Therapeutics against Coronaviruses, which was launched in early 2021, has attracted the scientific community at large, and more than 20 manuscripts have been accepted for publication.[...]
Flavivirus Persistence in Wildlife Populations
Authors: Blahove Maria Raisa , Carter James Richard
Published: October 2021

A substantial number of humans are at risk for infection by vector-borne flaviviruses, resulting in considerable morbidity and mortality worldwide. These viruses also infect wildlife at a considerable rate, persistently cycling between ticks/mosquitoes and small mammals and reptiles and non-human primates and humans. Substantially increasing evidence of viral persistence in wildlife continues to be reported. In addition to in humans, viral persistence has been shown to establish in mammalian, reptile, arachnid, and mosquito systems, as well as insect cell lines. Although a considerable amount of research has centered on the potential roles of defective virus particles, autophagy and/or apoptosis-induced evasion of the immune response, and the precise mechanism of these features in flavivirus persistence have yet to be elucidated. In this review, we present findings that aid in understanding how vector-borne flavivirus persistence is established in wildlife. Research studies to be discussed include determining the critical roles universal flavivirus non-structural proteins played in flaviviral persistence, the advancement of animal models of viral persistence, and studying host factors that allow vector-borne flavivirus replication without destructive effects on infected cells. These findings underscore the viral–host relationships in wildlife animals and could be used to elucidate the underlying mechanisms responsible for the establishment of viral persistence in these animals.
Genome Editing of Rice eIF4G Loci Confers Partial Resistance to Rice Black-Streaked Dwarf Virus
Authors: Wang Wei , Ma Shuhui , Hu Peng , Ji Yinghua , Sun Feng
Published: October 2021

Rice black-streaked dwarf disease, caused by rice black-streaked dwarf virus (RBSDV), is a serious constraint in Chinese rice production. Breeding disease-resistant varieties through multigene aggregation is considered an effective way to control diseases, but few disease-resistant resources have been characterized thus far. To develop novel resources for resistance to RBSDV through CRISPR/Cas9-mediated genome editing, a guide RNA sequence targeting exon 1 of eIF4G was designed and cloned into a binary vector, pHUE401. This recombinant vector was used to generate mutations in the rice cultivar Nipponbare via Agrobacterium-mediated transformation. This approach produced heritable homozygous mutations in the transgene-free T1 generation. Sequence analysis of the eIF4G target region from T1 transgenic plants identified 3 bp deletion mutants, and analysis of the predicted amino acid sequence identified one amino acid deletion in mutants that possess near full-length eIF4G. Furthermore, our data suggest that eIF4G may plays an important role in rice normal development, as there were no eIF4G knock-out homozygous mutants in T1 generation plants. When homozygous mutant lines were inoculated with RBSDV, they exhibited enhanced tolerance to virus infection, without visibly affecting plant growth and development. However, the eif4g mutant plants showed the same sensitivity to rice stripe virus (RSV) infection as wild-type plants. Notably, the wild-type and mutant N-termini of eIF4G interacted directly with RBSDV P8 in yeast and in planta. Additionally, compared to wild-type plants, the eIF4G transcript level was reduced twofold in the mutant plants. These results indicate that site-specific mutation of rice eIF4G successfully conferred partial resistance specific to RBSDV associated with less transcription of eIF4G in mutants. Therefore, this study demonstrates that the novel eIF4G alleles generated by CRISPR/Cas9 represent valuable disease-resistant resources that can be used to develop RBSDV-resistant varieties.
Effect of Serial Systemic and Intratumoral Injections of Oncolytic ZIKVBR in Mice Bearing Embryonal CNS Tumors
Authors: Ferreira Raiane Oliveira , Granha Isabela , Ferreira Rodolfo Sanches , Bueno Heloisa de Siqueira , Okamoto Oswaldo Keith , Kaid Carolini , Zatz Mayana
Published: October 2021

The Zika virus (ZIKV) has shown a promising oncolytic effect against embryonal CNS tumors. However, studies on the effect of different administration routes and the ideal viral load in preclinical models are highly relevant aiming for treatment safety and efficiency. Here, we investigated the effect and effectiveness of different routes of administration, and the number of ZIKVBR injections on tumor tropism, destruction, and side effects. Furthermore, we designed an early-stage human brain organoid co-cultured with embryonal CNS tumors to analyze the ZIKVBR oncolytic effect. We showed that in the mice bearing subcutaneous tumors, the ZIKVBR systemically presented a tropism to the brain. When the tumor was located in the mice’s brain, serial systemic injections presented efficient tumor destruction, with no neurological or other organ injury and increased mice survival. In the human cerebral organoid model co-cultured with embryonal CNS tumor cells, ZIKVBR impaired tumor progression. The gene expression of cytokines and chemokines in both models suggested an enhancement of immune cells recruitment and tumor inflammation after the treatment. These results open new perspectives for virotherapy using the ZIKVBR systemic administration route and multiple doses of low virus load for safe and effective treatment of embryonal CNS tumors, an orphan disease that urges new effective therapies.