The Parsec-Scale Jets of the TeV Blazars H 1426+428, 1ES 1959+650, and PKS 2155-304: 2001-2004

We present Very Long Baseline Array (VLBA) observations of the TeV blazars H 1426+428, 1ES 1959+650, and PKS 2155-304 obtained during the years 2001 through 2004. We observed H 1426+428 at four epochs at 8 GHz, and found that its parsec-scale structure consisted of a ~17 mJy core and a single ~3 mJy jet component with an apparent speed of 2.09 +/- 0.53c. The blazar 1ES 1959+650 was observed at three epochs at frequencies of 15 and 22 GHz. Spectral index information from these dual-frequency observations was used to definitively identify the core of the parsec-scale structure. PKS 2155-304 was observed at a single epoch at 15 GHz with dual-circular polarization, and we present the first VLBI polarimetry image of this source. For 1ES 1959+650 and PKS 2155-304, the current observations are combined with the VLBA observations from our earlier paper to yield improved apparent speed measurements for these sources with greatly reduced measurement errors. The new apparent speed measured for component C2 in 1ES 1959+650 is 0.00 +/- 0.04c (stationary), and the new apparent speed measured for component C1 in PKS 2155-304 is 0.93 +/- 0.31c. We combine the new apparent speed measurements from this paper with the apparent speeds measured in TeV blazar jets from our earlier papers to form a current set of apparent speed measurements in TeV HBLs. The mean peak apparent pattern speed in the jets of the TeV HBLs is about 1c. We conclude the paper with a detailed discussion of the interpretation of the collected VLBA data on TeV blazars in the context of current theoretical models for the parsec-scale structure of TeV blazar jets.Comment: 16 pages, Astrophysical Journal, in pres

A Bayesian tool for epilepsy diagnosis in the resource-poor world: Development and early validation

AbstractPurposeThe epilepsy treatment gap in resource-poor countries is so large that existing numbers of doctors are unlikely to be able to close it. Other health workers are likely to be needed but they will need help. The diagnosis of an attack as epileptic or not is an essential step in the management of epilepsy. It should be possible to devise a tool to give the probability of episodes being epileptic based on a Bayesian analysis of the results of history taking.MethodWe asked about the nature of episodes in patients referred to epilepsy camps in Nepal. Answers were then compared to the final clinical diagnosis of epilepsy and the likelihood ratio (LR) of the episode being epileptic obtained for each answer. The most informative LRs, tested sequentially, formed the basis for a tool which was validated in a different Nepalese population.ResultsData was obtained from 67 patients. The pre-test probability of having epilepsy was 0.76. Answers to 11 questions with the most informative LRs were then combined into a tool. This was tested on 14 different patients. Post-test probability scores in those with epilepsy ranged from 0.88 to 1 and for those with non-epilepsy from 0.07 to 0.42.ConclusionIt is possible to devise a tool based on simple clinical information using Bayesian principles. Initial validation suggests that this has the potential to enable health workers to diagnose episodes as epileptic or not. This now needs to be tested in different populations. The tool is easily converted to a mobile phone app

Prevalence of Functional Limitation in COVID-19 Recovered Patients Using the Post COVID-19 Functional Status Scale

INTRODUCTION: COVID-19 is an emerging global health pandemic causing tremendous morbidity and mortality worldwide. Chronic symptoms progressing to poor functional status have been reported in a substantial proportion of COVID-19 patients worldwide. This study aimed to determine the prevalence of functional limitation in COVID-19 recovered patients using the post-COVID-19 functional status scale. METHODS: A descriptive cross-sectional study was conducted at Tribhuvan University Teaching Hospital. COVID-19 recovered patients with reverse transcription-polymerase chain reaction negative status were included and assessed using the post-COVID-19 functional status scale. Data entry and analysis was done in Statistical Package for the Social Sciences version 20.0. Descriptive statistics were performed. RESULTS: A total of 106 patients were included for the final analysis. More than half of the patients (56.6%) reported having no functional limitation (grade 0), while the prevalence of some degree of functional limitation was observed in 46 (43.4%) patients (grade 1 to 4). CONCLUSIONS: Some form of functional limitation should be anticipated after COVID-19 infection. Post-COVID-19 functional status scale can be a valuable tool in determining the prevalence of functional limitation in COVID-19 recovered patients in acute health care settings. It can potentially guide in planning rehabilitative measures in post-acute care management of COVID-19 survivors

Significant Limb-Brightening in the Inner Parsec of Markarian 501

We present three 43 GHz images and a single 86 GHz image of Markarian 501 from VLBA observations in 2005. The 86 GHz image shows a partially resolved core with a flux density of about 200 mJy and a size of about 300 Schwarzschild radii, similar to recent results by Giroletti et al. Extreme limb-brightening is found in the inner parsec of the jet in the 43 GHz images, providing strong observational support for a `spine-layer' structure at this distance from the core. The jet is well resolved transverse to its axis, allowing Gaussian model components to be fit to each limb of the jet. The spine-layer brightness ratio and relative sizes, the jet opening angle, and a tentative detection of superluminal motion in the layer are all discussed.Comment: Astrophysical Journal Letters, accepted for January 1, 2009 issu

Structure-based virtual screening methods for the identification of novel phytochemical inhibitors targeting furin protease for the management of COVID-19

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, is a highly contagious respiratory disease with widespread societal impact. The symptoms range from cough, fever, and pneumonia to complications affecting various organs, including the heart, kidneys, and nervous system. Despite various ongoing efforts, no effective drug has been developed to stop the spread of the virus. Although various types of medications used to treat bacterial and viral diseases have previously been employed to treat COVID-19 patients, their side effects have also been observed. The way SARS-CoV-2 infects the human body is very specific, as its spike protein plays an important role. The S subunit of virus spike protein cleaved by human proteases, such as furin protein, is an initial and important step for its internalization into a human host. Keeping this context, we attempted to inhibit the furin using phytochemicals that could produce minimal side effects. For this, we screened 408 natural phytochemicals from various plants having antiviral properties, against furin protein, and molecular docking and dynamics simulations were performed. Based on the binding score, the top three compounds (robustaflavone, withanolide, and amentoflavone) were selected for further validation. MM/GBSA energy calculations revealed that withanolide has the lowest binding energy of −57.2 kcal/mol followed by robustaflavone and amentoflavone with a binding energy of −45.2 kcal/mol and −39.68 kcal/mol, respectively. Additionally, ADME analysis showed drug-like properties for these three lead compounds. Hence, these natural compounds robustaflavone, withanolide, and amentoflavone, may have therapeutic potential for the management of SARS-CoV-2 by targeting furin