The calculation of sample size helps a medical researcher to assess cost, time, and feasibility of his project besides scientific justification and validity. Although frequently reported in journals, ...the details or the elements of sample size calculation are not consistently provided by the authors. Sample size calculations reported do not match with replication of sample size in many studies. Most trials with negative results do not have a large enough sample size. Hence, reporting of sample size and power needs to be improved. The sample size calculation can be guided by previous literature, pilot studies, and past clinical experiences. The collaborative effort of the researcher and the statistician is required at this stage. Estimated sample size is our best guess. Issues such as anticipated loss to follow-up, large subgroup analysis, and complicated study designs, demand a large sample size to ensure power throughout the trial. The present article will help the reader understand the importance of pilot study in sample size estimation, second understand the relationship between primary objective and sample size of a study, third understand the essential components required in a sample size estimation, and fourth calculate sample sizes using real-life examples using an online software.
BBV152 is a whole-virion inactivated SARS-CoV-2 vaccine that has been deployed in India. The results of the phase 3 trial have shown clinical efficacy of BBV152. We aimed to evaluate the ...effectiveness of BBV152 against symptomatic RT-PCR-confirmed SARS-CoV-2 infection.
We conducted a test-negative, case-control study among employees of the All India Institute of Medical Sciences (a tertiary care hospital in New Delhi, India), who had symptoms suggestive of COVID-19 and had an RT-PCR test for SARS-CoV-2 during the peak of the second wave of the COVID-19 pandemic in India between April 15 and May 15, 2021. Cases (test-positives) and controls (test-negatives) were matched (1:1) on the basis of age and gender. The odds of vaccination with BBV152 were compared between cases and controls and adjusted for level of occupational exposure (to COVID-19), previous SARS-CoV-2 infection, and calendar time, using conditional logistic regression. The primary outcome was effectiveness of two doses of BBV152 (with the second dose received at least 14 days before testing) in reducing the odds of symptomatic RT-PCR-confirmed SARS-CoV-2 infection, expressed as (1 – odds ratio) × 100%.
Between April 15 and May 15, 2021, 3732 individuals had an RT-PCR test. Of these, 2714 symptomatic employees had data on vaccination status, and 1068 matched case-control pairs were available for analysis. The adjusted effectiveness of BBV152 against symptomatic COVID-19 after two doses administered at least 14 days before testing was 50% (95% CI 33–62; p<0·0001). The adjusted effectiveness of two doses administered at least 28 days before testing was 46% (95% CI 22–62) and administered at least 42 days before testing was 57% (21–76). After excluding participants with previous SARS-CoV-2 infections, the adjusted effectiveness of two doses administered at least 14 days before testing was 47% (95% CI 29–61).
This study shows the effectiveness of two doses of BBV152 against symptomatic COVID-19 in the context of a huge surge in cases, presumably dominated by the potentially immune-evasive delta (B.1.617.2) variant of SARS-CoV-2. Our findings support the ongoing roll-out of this vaccine to help control the spread of SARS-CoV-2, while continuing the emphasis on adherence to non-pharmacological measures.
None.
For the Hindi translation of the abstract see Supplementary Materials section.
We introduce an advancement in Morita–Baylis–Hillman (MBH) chemistry that provides access to α-spirannulated enones. The treatment of enone-tethered azaarenium salts with catalytic amounts of ...organophosphines provides spiroindenyl dihydropyridines. It represents the α-spirannulation of enones via an intramolecular MBH (IMBH) reaction utilizing dual phosphine- and anion-binding catalysis. The IMBH adducts were subjected to several post-synthetic modifications to access highly functionalized molecules.
Microglial overactivation promotes the production of various second messengers and inflammatory markers in brain tissue, resulting in neuroinflammation and neurodegeneration, which may lead to ...cognitive decline. The cyclic nucleotides are one of the important second messengers involved in the regulation of neurogenesis, synaptic plasticity, and cognition. The levels of these cyclic nucleotides are maintained by phosphodiesterase enzyme isoforms, particularly PDE4B, in the brain. An imbalance between PDE4B levels and cyclic nucleotides may lead to aggravating neuroinflammation.
Lipopolysaccharides (LPS) were administered intraperitoneally on alternate days for 7 days at a dose of 500 μg/kg in mice, which triggered systemic inflammation. This may lead to the activation of glial cells and may activate oxidative stress and neuroinflammatory markers in brain tissue. Furthermore, oral administration of roflumilast (0.1, 0.2, and 0.4 mg/kg) in this model ameliorated oxidative stress markers, neuroinflammation and improved neurobehavioral parameters in these animals.
The detrimental effect of LPS increased oxidative stress, AChE enzyme levels, and decreased catalase levels in brain tissues, along with memory impairment in animals. Moreover, it also enhanced the activity and expression of the PDE4B enzyme, resulting in a decline in cyclic nucleotide levels. Furthermore, treatment with roflumilast improved the cognitive decline, decreased AChE enzyme level, and increased the catalase enzyme level. Roflumilast also reduced the PDE4B expression in a dose-dependent manner, which LPS up-regulated.
Roflumilast has shown an anti-neuroinflammatory effect and reversed the cognitive decline in LPS-induced mice model.
Cyclodextrins are cyclic oligosaccharides characterized by a hydrophobic interior and a hydrophilic outside linked by α-1,4 glycosidic bonds. Cyclodextrins are biodegradable and generally considered ...environmentally friendly. These are utilized in diverse applications, encompassing environmental cleanup which is enhanced through the processes of cross-linking or surface modification. These molecules have a unique structure that enables them to form inclusion complexes with various guest molecules, including organic pollutants, pesticides, dyes, pharmaceuticals, and hydrocarbons. When used in water treatment, cyclodextrins can act as molecular sponges, trapping pollutants within their cavities through non-covalent interactions such as hydrogen bonding, van der Waals forces, and hydrophobic interactions. When cyclodextrins are introduced into water containing pollutants, the pollutants can enter the cavities of cyclodextrin molecules, forming inclusion complexes. This process effectively sequesters the pollutants from the surrounding water, reducing their concentration. It can often be regenerated and reused multiple times, making them cost-effective for water treatment applications. This review presents the primary applications of cyclodextrins for the adsorption of contaminants from various pollutants from diverse sources, based on recent publications.
There are limited data on the effect of chronic pancreatitis (CP) on pregnancy outcomes and vice versa. Our aim was to evaluate the clinical trajectory of CP during pregnancy and its effect on ...pregnancy outcomes.
All female patients of child-bearing age (≥15 years) diagnosed with CP were studied from January 2004 to July 2019. The change in frequency of painful episodes was assessed before, during, and after pregnancy. Maternal and fetal outcomes were compared between pregnant women (early onset) and women presenting with CP after completion of all pregnancies (late onset).
Of 187 women with CP, pregnancy outcomes and clinical course were assessed in 99 patients. The frequency of painful exacerbations was significantly lower during pregnancy compared with prepregnancy and postpregnancy periods (P < 0.001). The median pain score decreased significantly to 0 (0-2) during pregnancy from 3 (0-6) before conception and increased to 4 (0-8) after pregnancy (P = 0.002). Women with early onset CP (n = 57) had their first child later and had fewer pregnancies compared with those with late onset CP (n = 42). There was no difference in maternal outcomes such as gestational diabetes, hypertension, and preterm delivery, and fetal outcomes such as abortion, low birth weight, and still birth between the groups. There was no reported congenital anomaly.
Younger patients with CP had later and fewer pregnancies, but there was no increased risk of adverse maternal and fetal outcomes. The clinical course of CP was usually benign during pregnancy with decreased frequency and severity of pain.
A compact dual band 2 × 2 multiple-input-multiple-output (MIMO) antenna with dimension 46 × 30 × 1.6 mm
3
is reported. The designed CPW-fed MIMO antenna structure consists of swastika shaped slot in ...the rectangular patch. A T-shaped narrow conducting strip is used in ground plane to improve the isolation between the two radiating elements. The measured lower and upper frequency bandwidths are respectively 64.96% (1.85–3.63 GHz) and 44.36% (5.07–7.96 GHz), along with the corresponding isolation
≤
-
17.21 dB and
≤
-
22.42 dB. The measured realized gain changes from 1.14 to 4.12 dBi (lower band) and from 1.42 to 4.78 dBi (upper band) and the radiation efficiency is found over 72% for both the frequency bands. The antenna diversity parameters alongwith the radiation patterns are also investigated. Initially, the antenna is modelled using CST Microwave studio and the optimized design is fabricated and measured for validity of results.
Plasmodium infections are co-endemic with infections caused by other agents of acute febrile illnesses, such as dengue virus (DENV), chikungunya virus, Leptospira spp., and Orientia tsutsugamushi. ...However, co-infections may influence disease severity, treatment outcomes, and development of drug resistance. When we analyzed cases of acute febrile illness at the All India Institute of Medical Sciences, New Delhi, India, from July 2017 through September 2018, we found that most patients with malaria harbored co-infections (Plasmodium mixed species and other pathogens). DENV was the most common malaria co-infection (44% of total infections). DENV serotype 4 was associated with mild malaria, and Leptospira was associated with severe malaria. We also found the presence of P. knowlesi in our study population. Therefore, in areas with a large number of severe malaria cases, diagnostic screening for all 4 DENV serotypes, Leptospira, and all Plasmodium species should be performed.
Abstract
We present CAMELS-ASTRID, the third suite of hydrodynamical simulations in the Cosmology and Astrophysics with MachinE Learning (CAMELS) project, along with new simulation sets that extend ...the model parameter space based on the previous frameworks of CAMELS-TNG and CAMELS-SIMBA, to provide broader training sets and testing grounds for machine-learning algorithms designed for cosmological studies. CAMELS-ASTRID employs the galaxy formation model following the ASTRID simulation and contains 2124 hydrodynamic simulation runs that vary three cosmological parameters (Ω
m
,
σ
8
, Ω
b
) and four parameters controlling stellar and active galactic nucleus (AGN) feedback. Compared to the existing TNG and SIMBA simulation suites in CAMELS, the fiducial model of ASTRID features the mildest AGN feedback and predicts the least baryonic effect on the matter power spectrum. The training set of ASTRID covers a broader variation in the galaxy populations and the baryonic impact on the matter power spectrum compared to its TNG and SIMBA counterparts, which can make machine-learning models trained on the ASTRID suite exhibit better extrapolation performance when tested on other hydrodynamic simulation sets. We also introduce extension simulation sets in CAMELS that widely explore 28 parameters in the TNG and SIMBA models, demonstrating the enormity of the overall galaxy formation model parameter space and the complex nonlinear interplay between cosmology and astrophysical processes. With the new simulation suites, we show that building robust machine-learning models favors training and testing on the largest possible diversity of galaxy formation models. We also demonstrate that it is possible to train accurate neural networks to infer cosmological parameters using the high-dimensional TNG-SB28 simulation set.
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