Prevalence and patterns of physical activity among school aged adolescents in Pakistan: A systematic review and meta-analysis

Less than one fifth of Pakistani adolescents, aged 13–15, years achieve recommended activity levels. This systematic review and meta-analysis was conducted to determine a pooled estimate of the prevalence of PA, and to systematically evaluate the literature available on PA among adolescents in Pakistan. A systemic search of databases was conducted. In addition, hand search of references of all the included relevant publications was performed. Random effects meta-analysis was used to get weighted prevalence of PA among adolescents. Quality of undertaken studies was assessed using New-Castle Ottawa Scale. After removing duplicates, reviewing titles and abstracts and screening full texts, 15 articles were included for analysis. All studies were conducted in school setting, with a total sample size of 10,651. Weighted pooled prevalence of PA among adolescents was 36.0% with high heterogeneity (99.28%). Most of the studies met study quality assessment criteria except for comparability of subjects in different outcome groups and assessment of outcome. Prevalence of PA among adolescents is low in Pakistan. Formal strategies are needed for promoting PA among adolescents for their improved health and for reducing future burden of NCDs

CFD Analysis of Aerodynamic Drag Effects on Vacuum Tube Trains

Aerodynamic aspects of train shapes suitable for Vacuum Tube Train System are investigated in this paper. Three feasible geometries for the vacuum tube train system have been considered and modelled in three dimensions and have been computationally studied using the commercial software Ansys Fluent. Aerodynamic drag loads on these geometries have been calculated under different tube pressures and speeds of the train, which provide insight on various operating parameters that need to be considered while designing the vacuum tube train system. The present computational research shows that, the suitable vacuum pressure, and different shapes of head and tail of the train have significantly effects the drag force of the vacuum train in the tunnel. Overall, the elliptical train shape with a height to base ratio of 2:1 is more efficient for aerodynamic drag reduction of the vacuum tube train at the vacuum tube pressure of 1013.25 Pa

Computationally Inexpensive 1D-CNN for the Prediction of Noisy Data of NOx Emissions From 500 MW Coal-Fired Power Plant

Coal-fired power plants have been used to meet the energy requirements in countries where coal reserves are abundant and are the key source of NOx emissions. Owing to the serious environmental and health concerns associated with NOx emissions, much work has been carried out to reduce NOx emissions. Sophisticated artificial intelligence (AI) techniques have been employed during the past few decades, such as least-squares support vector machine (LSSVM), artificial neural networks (ANN), long short-term memory (LSTM), and gated recurrent unit (GRU), to develop the NOx prediction model. Several studies have investigated deep neural networks (DNN) models for accurate NOx emission prediction. However, there is a need to investigate a DNN-based NOx prediction model that is accurate and computationally inexpensive. Recently, a new AI technique, convolutional neural network (CNN), has been introduced and proven superior for image class prediction accuracy. According to the best of the author’s knowledge, not much work has been done on the utilization of CNN on NOx emissions from coal-fired power plants. Therefore, this study investigated the prediction performance and computational time of one-dimensional CNN (1D-CNN) on NOx emissions data from a 500 MW coal-fired power plant. The variations of hyperparameters of LSTM, GRU, and 1D-CNN were investigated, and the performance metrics such as RMSE and computational time were recorded to obtain optimal hyperparameters. The obtained optimal values of hyperparameters of LSTM, GRU, and 1D-CNN were then employed for models’ development, and consequently, the models were tested on test data. The 1D-CNN NOx emission model improved the training efficiency in terms of RMSE by 70.6% and 60.1% compared to LSTM and GRU, respectively. Furthermore, the testing efficiency for 1D-CNN improved by 10.2% and 15.7% compared to LSTM and GRU, respectively. Moreover, 1D-CNN (26 s) reduced the training time by 83.8% and 50% compared to LSTM (160 s) and GRU (52 s), respectively. Results reveal that 1D-CNN is more accurate, more stable, and computationally inexpensive compared to LSTM and GRU on NOx emission data from the 500 MW power plant

Tunnelling Methods and Hawking's radiation: achievements and prospects

The aim of this work is to review the tunnelling method as an alternative description of the quantum radiation from black holes and cosmological horizons. The method is first formulated and discussed for the case of stationary black holes, then a foundation is provided in terms of analytic continuation throughout complex space-time. The two principal implementations of the tunnelling approach, which are the null geodesic method and the Hamilton-Jacobi method, are shown to be equivalent in the stationary case. The Hamilton-Jacobi method is then extended to cover spherically symmetric dynamical black holes, cosmological horizons and naked singularities. Prospects and achievements are discussed in the conclusions.Comment: Topical Review commissioned and accepted for publication by "Classical and Quantum Gravity". 101 pages; 6 figure

Herd immunity against severe acute respiratory syndrome coronavirus 2 infection in 10 communities, qatar

We investigated what proportion of the population acquired severe acute respiratory syndrome coronavirus 2 (SARSCoV- 2) infection and whether the herd immunity threshold has been reached in 10 communities in Qatar. The study included 4,970 participants during June 21-September 9, 2020. Antibodies against SARS-CoV-2 were detected by using an electrochemiluminescence immunoassay. Seropositivity ranged from 54.9% (95% CI 50.2%-59.4%) to 83.8% (95% CI 79.1%-87.7%) across communities and showed a pooled mean of 66.1% (95% CI 61.5%-70.6%). A range of other epidemiologic measures indicated that active infection is rare, with limited if any sustainable infection transmission for clusters to occur. Only 5 infections were ever severe and 1 was critical in these young communities; infection severity rate of 0.2% (95% CI 0.1%-0.4%). Specifi c communities in Qatar have or nearly reached herd immunity for SARS-CoV-2 infection: 65%-70% of the population has been infected.This study was supported by the Hamad Medical Corporation, Ministry of Public Health, and the Biomedical Research Program and the Biostatistics, Epidemiology, and Biomathematics Research Core, both atScopu

Knowledge, Attitudes and Practices Regarding Diabetes in the General Population: A Cross-Sectional Study from Pakistan.

Background: Low knowledge about diabetes risk factors coupled with high disease prevalence is common in low-resource countries. This study evaluated diabetes-related knowledge, attitudes, and practices in the general population in Punjab (Pakistan). Methods: A cross-sectional study was conducted in five districts in Punjab from January to March 2017. Data were collected from 2019 adults aged 18⁻90 years through face-to-face interviews using a semi-structured questionnaire. The total knowledge score ranged from 0⁻9; a score ≥6 was considered adequate diabetes awareness. Descriptive statistics, chi-square tests, and linear and binary logistic regression were used for the analyses. Results: Respondents' mean age was 32.92 ± 11.4 years. In total, 85.9% of respondents had heard of diabetes, and 30.1% knew about the glucose tolerance test. We found 2.3% of respondents scored zero for diabetes knowledge, 11.3% scored 9, and 47.4% scored ≥6 (adequate awareness). Being female (β = 0.37, 95% confidence interval [CI]: 0.16, 0.05; p = 0.001), socioeconomic status (β = 0.24, 95% CI: 0.12, 0.36; p < 0.001), being diabetic (β = 0.82, 95% CI: 0.53, 1.10; p < 0.001), and higher education (β = 0.25, 95% CI: 0.17, 0.33; p < 0.001) were significantly associated with knowledge score. Respondents with high socioeconomic status showed significantly higher positive attitudes compared with those with low socioeconomic status (adjusted odds ratio 1.57, 95% CI: 1.12, 2.24). Only 8.7% (30/343) of those diagnosed with diabetes had never undergone blood glucose screening since diagnosis. Conclusions: Knowledge of diabetes risk factors, management, and care is low in Pakistan's general population. Targeted public education programs should be instigated at a national level to increase understanding of diabetes prevention and treatment

Reactivity of (η3-allyl)dicarbonylnitrosyl iron complexes with dimethyl malonate and diisobutyl malonate

In this paper, we describe the reactivity of our previously reported (η3-allyl)dicarbonylnitrosyl iron complexes (1–9). In this context, stoichiometric reactions of 1–9 with dimethyl malonate and di-iso-butyl malonate were carried out. The regioselectivity of the resulting products (10–25) was determined by gas chromatoraphic analysis of reaction mixtures. These products were purified by column chromatography and then structurally characterized by IR, 1H NMR, 13C NMR spectroscopies and mass spectrometry. Effect of different ligands L (L = CO, PPh3, SIMES (1,3-di-tert-butylimidazolium hexafluoro phosphate), BUSI(1,3-bis(2,4,6-trimethyl-phenyl)-4,5-dihydro-3H-imidazol-1-ium hexafluorophosphate)) and their influence on the substitution pattern has also been studied. The introduction of variable substituents exhibited diverse reactivities. Generally, it was observed that the reactivity decreased by increasing the size of substituentin (η3-allyl)dicarbonylnitrosyl iron complexes (1–9). Strong impact on the reactivity was observed due to substitution pattern of the allyl moiety. A considerable reduction in the conversion ratio from 81% to 68% was observed in repositioning the substituent from C-3 to C-2 position