Explore the vast range of titles available.

We consider the equation of motion of a charged particle or a charged compact object in curved space-time, under the reaction of electromagnetic radiation and also consider a physical situation such that the charged particle or compact object emits gravitational radiation, thereby gravitational radiation reaction also acts on it. We investigate the effect of this metric perturbation i.e. the gravitational radiation on the electromagnetic self-force. We show that, besides the interaction terms derived by Zimmerman and Poisson (Phys Rev D 90:084030, 2014), additional perturbative terms are generated, which are linear in metric perturbation and are generated due to perturbation of the electromagnetic self-force by the metric perturbation. We discuss the conditions of significance of these perturbative terms and also the interaction terms with respect to the gravitational self-force in various astrophysical and cosmological cases; such as the motion of charged particles around black holes, some extreme mass-ratio inspirals (EMRIs) involving sufficiently accelerated motion of charged stars (specially neutron stars) or charged stellar mass black holes around supermassive black holes, and motion of charged particles around charged primordial black holes formed in the early Universe etc. We find that in some astrophysical and cosmological cases these perturbative terms can have significant effect in comparison with the gravitational radiation-reaction term.

Coronavirus disease 2019 (COVID-19) is considered as the most dreaded disease that has spread all over the world in the recent past. Despite its outbreak in December 2019–January 2020, a few continents and countries such as India started to experience a significant number of COVID-19-positive cases from March 2020. GISAID clade variation analysis in the period March 2020–February 2021 (period I) and March 2021–first week of April 2021 (period II) showed a rapid variation of SARS-CoV-2 in all continents and India over time. Studying the relationship of patient age or gender with viral clades in these two periods revealed that the population under 10 years of age was the least affected, whereas the 11–60-year-old population was the most affected, irrespective of patient gender and ethnicity. In the first wave, India registered quite a low number of COVID-19-positive cases/million people, but the scenario unexpectedly changed in the second wave, when even over 400,000 confirmed cases/day were reported. Lineage analysis in India showed the emergence of new SARS-CoV-2 variants, i.e., B.1.617.1 and B.1.617.2, during April–May 2021, which might be one of the key reasons for the sudden upsurge of confirmed cases/day. Furthermore, the emergence of the new variants contributed to the shift in infection spread by the G clade of SARS-CoV-2 from 46% in period II to 82.34% by the end of May 2021. Along with the management of the emergence of new variants, few factors viz., lockdown and vaccination were also accountable for controlling the upsurge of new COVID-19 cases throughout the country. Collectively, a comparative analysis of the scenario of the first wave with that of the second wave would suggest policymakers the way to prepare for better management of COVID-19 recurrence or its severity in India and other countries.

Background: Vitiligo is an idiopathic acquired progressive de/hypopigmentary disorder of skin and mucosae. In Indian skin depigmentaion is very much obvious and can cause psychological distress, low self esteem and social stigmatization. Aims: The primary objective of this study was to evaluate the psychiatric morbidity in vitiligo patients and secondary objective was to assess the morbidity in all eight dimensions of psychosocial and physical aspects, i.e. cognitive, social, discomfort, limitations, depression, fear, embarrassment and anger. Materials and Methods: An institution based case-control study with sixty-one patients of vitiligo and equal number of healthy age and sex matched controls was undertaken. The self-reporting questionnaire-24 (SRQ-24) and skindex (A 61-item survey questionnaire) were used to assess the psychiatric morbidity in both the groups. Results: The SRQ-assessed psychiatric morbidity in the study group was 63.93%, compared with 24.59% in the control group (P<0.0001). Acral vitiligo had maximum association with psychiatric morbidity (86.67%) followed by vitiligo vulgaris (68%), mucosal vitiligo (62.5%) and others. According to the skindex, the most common psychiatric morbidity in vitiligo patients was depression (62.29%) followed by embarrassment (55.73%), social problem (54.09%), cognitive impairment (50.81%), physical limitation (47.54%), discomfort (40.98%), anger (36.06%) and fear (24.59%). The difference in Skindex scoring that marked the psychiatric morbidity among the case and control groups was statistically significant for depression, discomfort, social problem, cognitive impairment, embarrassment (P<0.0001) and physical limitation (P=0.0044). Conclusion: Vitiligo has a high degree of psychiatric morbidity.

We consider the propagation of gravitational waves in the late-time Universe in the presence of matter distribution inhomogeneities, and we also consider the cosmic fluid to be viscous. In this work, we investigate the cumulative effect of inhomogeneities and viscosity of the cosmic-fluid on the observables associated with the sources of the gravitational waves. Employing Buchert’s averaging procedure in the backreaction framework, we consider a model of spacetime in which matter is distributed in-homogeneously across space. Using the modified redshift versus distance relation, through the averaging process in the context of the model, we study the variation of the redshift-dependent part of the observed gravitational wave amplitude for different combinations of our model parameters while simultaneously considering damping of the gravitational wave amplitude due to viscosity of the cosmic-fluid. Then, we investigate the differences occurring in the variation of the redshift-dependent part of the observed gravitational wave amplitude due to consideration of viscous attenuation. We show that there are significant deviations after the inclusion of viscous attenuation in our analysis, depending on the chosen value of the coefficient of viscosity. Our result signifies the importance of the effect of viscosity, within the model of an inhomogeneous Universe, on precision measurements of parameters of compact-binary sources of gravitational waves.

To develop an accurate lab score based on in-hospital patients' potent clinical and biological parameters for predicting COVID-19 patient severity during hospital admission. To conduct this retrospective analysis, a derivation cohort was constructed by including all the available biological and clinical parameters of 355 COVID positive patients (recovered = 285, deceased = 70), collected in November 2020-September 2021. For identifying potent biomarkers and clinical parameters to determine hospital admitted patient severity or mortality, the receiver operating characteristics (ROC) curve and Fischer's test analysis was performed. Relative risk regression was estimated to develop laboratory scores for each clinical and routine biological parameter. Lab score was further validated by ROC curve analysis of the validation cohort which was built with 50 COVID positive hospital patients, admitted during October 2021-January 2022. Sensitivity vs. 1-specificity ROC curve (>0.7 Area Under the Curve, 95% CI) and univariate analysis (p<0.0001) of the derivation cohort identified five routine biomarkers (neutrophil, lymphocytes, neutrophil: lymphocytes, WBC count, ferritin) and three clinical parameters (patient age, pre-existing comorbidities, admitted with pneumonia) for the novel lab score development. Depending on the relative risk (p values and 95% CI) these clinical parameters were scored and attributed to both the derivation cohort (n = 355) and the validation cohort (n = 50). ROC curve analysis estimated the Area Under the Curve (AUC) of the derivation and validation cohort which was 0.914 (0.883-0.945, 95% CI) and 0.873 (0.778-0.969, 95% CI) respectively. The development of proper lab scores, based on patients' clinical parameters and routine biomarkers, would help physicians to predict patient risk at the time of their hospital admission and may improve hospital-admitted COVID-19 patients' survivability.

Background: On January 16, 2021, India rolled out the COVID vaccination drive. A successful and effective vaccination campaign requires much more than the availability of a safe and effective vaccine. This includes identifying vulnerable populations with lower vaccine confidence and identifying the drivers of vaccine hesitancy. Objective: This study aims to find out vaccine hesitancy among the tribal population regarding COVID-19 vaccination. Methods: It was an observational descriptive cross-sectional study, conducted at Manindranagar and Hatinagar gram panchayat of Berhampore Block of Murshidabad district, West Bengal, from June 2021-November 2021, among tribal people aged >18 years. A total of 198 tribal people were selected by applying the probability proportional to size sampling method. Participants were interviewed using predesigned, pretested, and semi-structured schedules. Potential predictors of hesitancy were investigated using the multivariate logistic regression model. Results: Vaccine hesitancy was present among 36.9% of the study participants. Fear of side effects (78.1%) was the most common reason of vaccine hesitancy. Only 30.8% of them received at least one dose of vaccine. Vaccine hesitancy was associated with decreased family income in the last 1 year (adjusted odds ratio [AOR] = 8.23), knowledge regarding vaccine (AOR = 0.41), adherence to COVID-appropriate behavior (AOR = 0.45), and trust on the local health-care worker (AOR = 0.32). Conclusion: Vaccine hesitancy among the tribal population is driven by a lack of knowledge and awareness. Their economic status, attitudes toward the health system, and accessibility factors may also play a major role in vaccine hesitancy. Extensive information, education, and communication activity, more involvement of health-care workers in the awareness campaign, and establishment of vaccination centers in tribal villages may be helpful.

Real-time scheduling strategies for safety-critical systems are primarily focused on ensuring correctness, both functional and temporal. In order to provide the desired predictability in such systems, it is often advisable that all timing requirements be guaranteed offline, before putting the system into operation. Formal approaches allow for all necessary and sufficiency conditions corresponding to a feasible schedule to be checked in a systematic manner. This enables formal approaches to act as effective mechanisms for providing timing guarantees required by safety-critical systems. In this work, we develop a scheduler synthesis framework for the optimal work-conserving scheduling of dynamically arriving, sporadic tasks using a formal approach known as “supervisory control of timed discrete-event systems” (SCTDES). The synthesis process starts with the construction of a resource-constraint-aware task execution model and a deadline-constraint-aware timing specification model, for each task in the given real-time system. The system model (i.e., composite task execution model) is then derived and transformed to guarantee work-conserving co-execution of tasks. Such a work-conserving approach enables the synthesis of schedules which avoid processor idling in the presence of ready-to-execute tasks. Next, we use the (transformed) system and specification models to obtain a supervisor which can be used to construct an optimal scheduler for the given real-time system. Finally, the applicability of the proposed scheme for real-world scenarios is shown by presenting a case study on an instrument control system (ICS).

Wind speed data should be fitted by a suitable statistical model like Weibull to determine expected number of hours per year in the critical wind speed range for a slender structure, which is required to determine the expected number of stress cycles in the projected working life of the structure. Apart from this, for the assessment of wind energy potential wind speed data should be fitted by an appropriate probability distribution. In the present scope of study, wind data of various locations of India have been fitted by Weibull model. Wind speed data are initially sampled in knot by Indian Meteorological Department and later converted into integer km/h before supplying them to the end user. Due to this conversion, wind speed data cannot be properly fitted by Weibull distribution and in this regard, the choice of appropriate class width becomes very much important. Without the choice of appropriate class width, estimated Weibull parameters become biased which would yield incorrect estimation of expected number of hours in critical wind speed ranges as well as wind energy potential. After taking appropriate class width of 4 km/h, it has been found that Weibull model is an adequate model to describe wind speed distributions of India. Weibull model has also been compared with other models such as Gamma and inverse Weibull distributions to establish its suitability than the others. In this study, the values of Weibull shape parameters vary from 1.3 to 2.3, whereas the values of scale parameters vary from 1.4 m/s to 6.5 m/s. The validity of Weibull model is also verified with a target confidence interval of 90%. The uncertainties involved in the estimation of available wind energy potential as well as the expected number of hours per year in critical wind speed ranges have also been considered due to random variation of wind climate in each year.

Diabetic cardiomyopathy (DCM) is a prominent contributor to morbidity and mortality in people with diabetes worldwide. In diabetic patients, it is a chronic condition that is characterized by ventricular hypertrophy (VH), diastolic dysfunction, alteration of systolic function, and reduced ejection fraction, ultimately leading to heart failure (HF). Despite being extensively understood, the underlying causes of DCM remain obscure. Growing evidence has identified the contribution of microRNAs (miRNAs), a small non-coding RNA molecule playing a crucial part in the pathogenesis of DCM. These miRNAs have been linked with several mechanistic pathways involved in DCM, including inflammation, insulin resistance and cardiomyocyte apoptosis. miRNAs related to DCM include miR-9, 30d, 34a, 142-3p, 144, 150, 208a, etc. Thus, miRNAs present themselves as novel targets for diagnostic biomarkers and mechanistic therapeutics, which may prove to be clinically more efficient than other therapeutic approaches. This review highlights the role of miRNAs, which can act as the nodes of signalling networks that regulate the progression of DCM and also tries to decipher the complicated cross-talk between miRNAs and DCM-related signalling pathways through various protein factors modulation, which includes RyR-2, TGF-β, IGF-1R, NF-κB and Nrf-2 and also immunological regulation of cardiomyocytes. There has also been a discussion of diagnostic and therapeutic management of various miRNAs in the management of DCM with recent clinical trials on diabetes and cardiovascular disorder with miRNA candidates and concluded with the future perspective of miRNAs as new novel theranostic tools in the emerging field of diagnostic and therapeutic management.

Adequate placental angiogenesis is critical for the establishment of the placental circulation and thus for normal feto-placental growth and development. Fatty acid-binding protein-4 (FABP4) plays a pro-angiogenic role in endothelial cells; however, very little information is available in placental first trimester trophoblast cells. Here we report that exogenously added FABP4 (exo-FABP4) stimulated tube formation (as a measure of in vitro angiogenesis) in HTR8/SVneo trophoblastic cells. HTR-8/SVneo cells were incubated in the presence of exogenously added FABP4 at different concentrations and time points. Cellular growth, proliferation, in vitro tube formation, expression of growth stimulatory-, fatty acid transporters, and angiogenic genes were investigated. Internalization of exo-FABP4 was carried out using immunocytochemistry. Radioactive fatty acid uptake was determined in the presence and absence of FABP4 metabolic inhibitor. Exo-FABP4 (10–100 ng/ml) stimulated proliferation of HTR8/SVneo cells as compared to control. Exo-FABP4 dose dependently increased growth and viability of the cells to the similar extent as done by 50 µM of arachidonic acid. Exo-FABP4-induced tube formation and proliferation were significantly inhibited by FABP4 (BMS309403) inhibitor. Exo-FABP4 stimulated the expression of growth stimulatory genes such as tissue inhibitor of matrix metalloproteinases-1 (TIMP1), insulin-like growth factor 1 (IGF1), and also prokineticin 2 (PROK2), the pro-angiogenic mediators in these cells. In addition, expressions of genes associated with proliferation and differentiation such as sonic hedgehog (SHH) and WNT1 inducible signalling pathway protein 1 (WISP1) were significantly expressed when cells were exposed to exo-FABP4. Our findings reveal a pro-angiogenic role of FABP4 in first trimester placental trophoblast cells and its regulation may have impact in placental physiology.