Effect of poloidal equilibrium flow and pressure gradient on the m/n = 2/1 tearing mode

The effect of equilibrium poloidal flow and pressure gradient on the m/n = 2/1 (m is the poloidal mode number and n is the toroidal mode number) tearing mode instability for tokamak plasmas is investigated. Based on the condition of ≠0 ( is plasma pressure), the radial part of motion equation is derived and approximately solved for large poloidal mode numbers (m). By solving partial differential equation (Whittaker equation) containing second order singularity, the tearing mode stability index Δ′ is obtained. It is shown that, the effect of equilibrium poloidal flow and pressure gradient has the adverse effect on the tearing mode instability when the pressure gradient is nonzero. The poloidal equilibrium flow with pressure perturbation partially reduces the stability of the classical tearing mode. But the larger pressure gradient in a certain poloidal flow velocity range can abate the adverse influence of equilibrium poloidal flow and pressure gradient. The numerical results do also indicate that the derivative of pressure gradient has a significant influence on the determination of instability region of the poloidal flow with pressure perturbation.

Enumeration of carbon and nitrogen contents of water-stable aggregates in layers of topsoils from cultivated and adjacent bush-fallow loamy soils

Soil organic carbon (SOC) and total soil nitrogen (TSN) dynamics have both pedological and agronomic basis. Knowledge of their retention within aggregate hierarchies of varying soil textures as influenced by land use change is limited. The capacity of loam (L), clay loam (CL), sandy loam (SL) and sandy clay loam (SCL) soils to retain SOC and TSN in water-stable aggregate (WSA) at 10-cm intervals of 0-30 cm topsoil depths under cultivated and bushfallow/ uncultivated systems was investigated. The soils showed high dispersion ratio and great variations in aggregate silt and clay indices (CL > L > SCL > SL) under both land uses. Across soil depths, the uncultivated CL, SL and SCL soils had moderate to high > 2.00 mm WSA whose reduction due to cultivation impact was more pronounced in SL than in CL soil. Across soil depths and land uses, SOC content seemed higher in the macro- (> 0.50 mm) than in the micro- (< 0.50 mm) aggregates of all the soils while the reverse marked aggregate TSN content in almost all the soils. Cultivation mostly reduced macro-aggregate-associated SOC and TSN in L > CL > SL and in L > SL > CL > SCL soils, respectively. However, cultivation showed no reduction influence on micro-aggregate-associated SOC of all the soils. Cultivation-related reduction in micro-aggregate-associated TSN was more pronounced in the generally more ‘clayey’ CL and SCL than the L and SL soils. So, the potential of bush-fallowing to enhance micro-aggregateassociated TSN storage and stabilization against adverse influence of cultivation depends on soil texture.

Board Gender Diversity, Firm Performance and Risk-Taking: The Case of Non-Financial Firms of Pakistan

This paper examines the influence of board gender diversity on firm performance and risk taking. We employed the panel data of seventy-five non-financial firms of KSE-100 index listed in the Pakistan Stock Exchange. The data consists of 2005-2018 period. Results of panel regression reveal that board gender diversity have adverse influence on the firm performance i-e Tobin’s Q and return on assets. Moreover, it further provides that board gender diversity has decrease the firm’s risk-taking i-e insolvency risk. Overall, the inclusion of females in the boardroom reduces the financial performance and decrease the risk-taking of non-financial firms in Pakistan. This study provides the managerial and practical implications in compliance with SECP Act of 2017, to include the females in boardroom to discourage the risk-taking behavior of firms.

The influence of drinkers on the affective status of representatives of their microsocial environment

The purpose of the work is to study the adverse influence of drinkers on the affective status of representatives of their microsocial environment. In four regions of Ukraine (Kharkiv, Lugansk and Zaporizhzhia regions, as well as the city of Kyiv), during 2018—2021, 1742 people were examined, who belonged to three qualitatively different comparison groups: patients with alcohol dependence (AD) (393 people); healthy relatives of alcohol-dependent patients (274 people) and representatives of the general population (1075 people). Of these surveyed, respondents were identified who had drinkers in the environment: 288 persons among healthy people and 121 persons among patients with AD. Further research focused on this particular contingent. The main research tool was the questionnaire of the international research consortium GENAHTO (Gender, Alcohol, and Harms to Others) and Hamilton Depression Rating Scale (HDRS). The obtained data were processed by methods of mathematical statistics (variance and cluster analysis) on a computer using Excel 2016 computational tables (with the Data Analysis package) and also the software package SPSS-15. It was shown that the presence of drinkers in environment of the women significantly increases the proportion of people with depressive disorders among them, while among the male respondents, this effect was not found. It was revealed that the presence of drinkers in environment of the women significantly increases the severity of such manifestations of depression as: insomnia, weight loss, sexual dysfunctions; suicidal tendencies and guilt. Using cluster analysis, the following typical symptom complexes (important for choosing the optimal therapeutic tactics) were established: insomnia-somatoform, hypochondriacal and anxiety-agitational (the latter — with a sense of guilt and an increased risk of suicidal activity).

Impact of SARS-CoV-2 infection on veterinary medical education

SARS-CoV-2 infection is considered an international disaster. The second and third waves of the SARSCoV-2 pandemic are ongoing. The universities of most countries of the world are closed to prevent the spread of SARS-CoV-2 infection. Many universities of the globe stopped direct classroom teaching, and some started online teaching to minimise the effects of SARS-CoV-2 on education. In this manuscript, an attempt has undertaken to analyse the influence of the SARS-CoV-2 pandemic on global veterinary medical education. We have conducted a literature search in different databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using different keywords to find out peer-reviewed scientific articles about the impact of COVID-19 on veterinary medical education. The literature search generated 17 eligible scientific papers for qualitative analysis of the effect of COVID-19 on veterinary medical education. The COVID-19 pandemic has a severe adverse influence on veterinary medical education. Shifting from direct classroom teaching to online teaching is one of the sweeping impacts. It might be possible to conduct online classes for veterinary medical education. But the supply of electronic devices, motivation to students in self-learning, institutional support etc., are crucial for interactive situated learning of veterinary courses. Research and development of sustainable, worthwhile methods for remote teaching veterinary medical students are essential. Reshaping the veterinary medical education programs using core theory, practical and clinical curricula is crucial for conducting uninterrupted veterinary education programs during current COVID-19 and future pandemics.

Hydrogen sulfide blocks HIV rebound by maintaining mitochondrial bioenergetics and redox homeostasis

A fundamental challenge in HIV eradication is to understand how the virus establishes latency, maintains stable cellular reservoirs, and promotes rebound upon interruption of antiretroviral treatment (ART). Here, we discovered an unexpected role of the ubiquitous gasotransmitter hydrogen sulfide (H2S) in HIV latency and reactivation. We show that reactivation of HIV-1 is associated with down-regulation of the key H2S producing enzyme cystathionine-g-lyase (CTH) and reduction in endogenous H2S. Genetic silencing of CTH disrupts redox homeostasis, impairs mitochondrial function, and remodels the transcriptome of latent cells to trigger HIV reactivation. Chemical complementation of CTH activity using a slow-releasing H2S donor, GYY4137, suppressed HIV reactivation and diminished virus replication. Mechanistically, GYY4137 blocked HIV reactivation by inducing the Keap1-Nrf2 pathway, inhibiting NF-kB, and recruiting the epigenetic silencer, YY1, to the HIV promoter. In latently infected CD4+ T cells from ART-suppressed human subjects, GYY4137 in combination with ART prevented viral rebound and improved mitochondrial bioenergetics. Moreover, prolonged exposure to GYY4137 exhibited no adverse influence on proviral content or CD4+ T cell subsets, indicating that diminished viral rebound is due to a loss of transcription rather than a selective loss of infected cells. In summary, this work provides mechanistic insight into H2S-mediated suppression of viral rebound and suggests exploration of H2S donors to maintain HIV in a latent form.

Zuogui Pill Attenuates Neuroinflammation and Improves Cognitive Function in Cerebral Ischemia Reperfusion-Injured Rats

<b><i>Introduction:</i></b> Cerebral ischemia and reperfusion (CI/R) injury is a devasting cerebrovascular disease, accompanied with ischemia stroke, cerebral infarction. Zuogui Pill (ZGP), as a Chinese traditional medicine, is proved to be effective in many diseases and cancers. Our study aimed to detect the roles of ZGP in CI/R injury. <b><i>Methods:</i></b> Neural stem cells were isolated from rats and induced by oxygen and glucose deprivation and recovery. CCK-8 and flow cytometry were applied to assess the function of ZGP on cell viability and apoptosis. Rat CI/R injury models were established by the middle cerebral artery occlusion and reperfusion. The function of ZGP on CI/R injury was identified via evaluating modified neurological severity score, infarct area, and cognitive impairment. <b><i>Results:</i></b> Compared to the control, the cell viability was obviously decreased in the oxygen and glucose deprivation and recovery (OGD/R) group, while the adverse influence on cells was reversed by cultured plus 10% ZGP serum. Consistently, ZGP attenuated the influence of OGD/R on cell apoptosis. More importantly, ZGP could alleviate CI/R injury of rats by reducing neurological damage and infarct area and promoting cognitive function. <b><i>Conclusion:</i></b> This study provided protective roles of ZGP on cell viability and apoptosis induced by OGD/R. In addition, ZGP played protective roles on neuroinflammation and cognitive function in rats.

Face masks impair reconstruction of acoustic speech features and higher-level segmentational features in the presence of a distractor speaker

Face masks have become a prevalent measure during the Covid-19 pandemic to counteract the transmission of SARS-CoV 2. An unintended “side-effect” of face masks is their adverse influence on speech perception especially in challenging listening situations. So far, behavioural studies have not pinpointed exactly which feature(s) of speech processing face masks affect in such listening situations. We conducted an audiovisual (AV) multi-speaker experiment using naturalistic speech (i.e. an audiobook). In half of the trials, the target speaker wore a (surgical) face mask, while we measured the brain activity of normal hearing participants via magnetoencephalography (MEG). A decoding model on the clear AV speech (i.e. no additional speaker and target speaker not wearing a face mask) was trained and used to reconstruct crucial speech features in each condition. We found significant main effects of face masks on the reconstruction of acoustic features, such as the speech envelope and spectral speech features (i.e. pitch and formant frequencies), while reconstruction of higher level features of speech segmentation (phoneme and word onsets) were especially impaired through masks in difficult listening situations, i.e. when a distracting speaker was also presented. Our findings demonstrate the detrimental impact face masks have on listening and speech perception, thus extending previous behavioural results. Supporting the idea of visual facilitation of speech is the fact that we used surgical face masks in our study, which only show mild effects on speech acoustics. This idea is in line with recent research, also by our group, showing that visual cortical regions track spectral modulations. Since hearing impairment usually affects higher frequencies, the detrimental effect of face masks might pose a particular challenge for individuals who likely need the visual information about higher frequencies (e.g. formants) to compensate.