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Objectives: To validate and recalibrate the CURB-65 and pneumonia severity index (PSI) in predicting 30-day mortality and critical care intervention (CCI) in a multiethnic population with COVID-19, along with evaluating both models in predicting CCI. Methods: Retrospective data was collected for 1181 patients admitted to the largest hospital in Qatar with COVID-19 pneumonia. The area under the curve (AUC), calibration curves, and other metrics were bootstrapped to examine the performance of the models. Variables constituting the CURB-65 and PSI scores underwent further analysis using the Least Absolute Shrinkage and Selection Operator (LASSO) along with logistic regression to develop a model predicting CCI. Complex machine learning models were built for comparative analysis. Results: The PSI performed better than CURB-65 in predicting 30-day mortality (AUC 0.83, 0.78 respectively), while CURB-65 outperformed PSI in predicting CCI (AUC 0.78, 0.70 respectively). The modified PSI/CURB-65 model (respiratory rate, oxygen saturation, hematocrit, age, sodium, and glucose) predicting CCI had excellent accuracy (AUC 0.823) and good calibration. Conclusions: Our study recalibrated, externally validated the PSI and CURB-65 for predicting 30-day mortality and CCI, and developed a model for predicting CCI. Our tool can potentially guide clinicians in Qatar to stratify patients with COVID-19 pneumonia.

The temperature regulation of photovoltaic (PV) modules using passive approach with phase-change materials (PCMs) has fascinated many researchers now-a-days. This article presents real-time experimental investigation of PV panels with PCM under warm climate of Taxila, Pakistan in two phases. In first phase, effect of fins inserted into PCM, is examined by varying number of fins as 2, 5, 8 and 11. Due to improved heat conduction within PCM through metal contact, PV cell temperature lowered by maximum 22.9 °C, 23.7 °C, 24.1 °C, 24.9 °C and 26.5 °C with finless, 2-fin, 5-fin, 8-fin and 11-fin PV/PCM configurations respectively, improving electrical conversion efficiency from 10.2% to 10.9%, 11.3%, 11.6%, 11.8% and 12.2% respectively. In second phase, effect of using 2 PCMs of different melting points, separated by finned-aluminum plate, is investigated and compared with one PCM for PV cooling. It is found that one PCM configuration is more efficient than two PCM configurations as cell temperature lowers on average by 9.7 °C, 7.9 °C and 7 °C with one PCM configuration and two different configurations (i.e. different order) of 2 PCMs respectively. Electrical power output also enhances by 13.3%, 8.8%, and 7.8% respectively. 2-PCM configurations shows better performance than 1-PCM configuration in case only when it is compared to 1-PCM configuration having PCM of higher melting point. Order of PCMs has no significant effect on PV-performance.

With the proliferation of decentralised power generation technologies and smart grid infrastructures, residential renewable energy generation (REG) has burgeoned to become intrinsic to modern power grids and is expected to play a fundamental role for the realization of netzero energy buildings to cater to the ever-escalating energy demand. The integration of domestic REG into the utility grid necessitates a medium of intelligent devices to perform net metering operations. Henceforth, we propose one such cost effective smart net-metering device for household REG systems with in-built wireless bi-directional communication based on Internet of Things (IoT) technology. Net metering operations are implemented using a microcontroller to synchronously collect, analyze and transmit data from sensors installed at the utility to consumer and REG to utility sides to both an offline display and an online server via a WiFi module interfaced to the microcontroller. We successfully implemented a prototype device for real-time energy monitoring over a sustained period of time, yielding accurate power generation and energy transfer statistics with remote-control operations. These results demonstrate the considerable potential for the prototype to be a stimulant in catalysing our eventual shift to decentralised power generation.

A cadmium-resistant bacterium was isolated from industrial wastewater and identified as Escherichia coli (dubbed as P4) on the basis of morphological, biochemical tests and 16S rRNA ribotyping. It showed optimum growth at 30 °C and pH 7. E. coli P4 found to resist Cd(+2) (10.6 mM) as well as Zn(+2) (4.4 mM), Pb(+2) (17 mM), Cu(+2) (3.5 mM), Cr(+6) (4.4 mM), As(+2) (10.6 mM), and Hg(+2) (0.53 mM). It could remove 18.8, 37, and 56 % Cd(+2) from aqueous medium after 48, 96, and 144 h, respectively. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and Energy-dispersive X-ray (EDX) analysis also confirmed the biosorption of Cd(+2) by E. coli P4. However, temperature and pH were found to be the most critical factors in biosorption of Cd(+2) by E. coli P4. Cd(+2) stress altered E. coli P4 cell physiology analyzed by measuring glutathione (GSH) and non-protein thiol (cysteine) levels which were increased up to 130 and 48 %, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) showed alteration in the expression levels of ftsZ, mutS, clpB, ef-tu, and dnaK genes in the presence of Cd(+2). Total protein profiles of E. coli P4 in the absence and presence of Cd(+2) were compared by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), which showed remarkable difference in the banding pattern. czcB gene, a component of czcCBA operon, was amplified from genomic DNA which suggested the chromosomal-borne Cd(+2) resistance in E. coli P4. Furthermore, it harbors smtAB gene which plays a significant role in Cd(+2) resistance.

The main objective of this research is to evaluate the relationship among charismatic leadership, leadership effectiveness and team performance. Current research has presented three hypotheses. For conducting this research data was collected randomly from the 80 employees of newly established microfinance bank APNA Bank. Results of this research have proved that all proposed three hypotheses are accepted. The results of the propose research have proved that charismatic leadership and leadership effectiveness are good predictors of team performance. Current research is also proposed the two dimensional hypothesis between charismatic leadership and leadership effectiveness. Results show that both are good predictors of each other’s. But charismatic leadership is good predictor of leadership effectiveness. For two way relationship of leadership effectiveness and team performance, leadership effectiveness is good predictor of team performance. In future researches, more studies will be done on other sectors like textile sector, pharmaceutical sectors etc. In future researches, other variable like cohesiveness and customer satisfaction etc will be included along with other variables.

Background : Rapid industrialization is discharging toxic heavy metals into the environment, disturbing human health in many ways and causing various neurologic, cardiovascular, and dermatologic abnormalities and certain types of cancer. The presence of arsenic in drinking water from different urban and rural areas of the major cities of Pakistan, for example, Lahore, Faisalabad, and Kasur, was found to be beyond the permissible limit of 10 parts per billion set by the World Health Organization. Therefore the present study was initiated to examine the effects of arsenite (As +3 ) on DNA biosynthesis and cell death. Methods : After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and flow cytometry. Results : We show that As +3 ions have a dose- and time-dependent cytotoxic effect through the activation of the caspase-dependent apoptotic pathway. In contrast to previous research, the present study was designed to explore the early cytotoxic effects produced in human cells during exposure to heavy dosage of As +3 (7.5 µg/ml). Even treatment for 1 h significantly increased the mRNA levels of p21 and p27 and caspases 3, 7, and 9. It was interesting that there was no change in the expression levels of p53, which plays an important role in G 2 /M phase cell cycle arrest. Conclusion : Our results indicate that sudden exposure of cells to arsenite (As +3 ) resulted in cytotoxicity and mitochondrial-mediated apoptosis resulting from up-regulation of caspases. Keywords: apoptosis; epithelial carcinoma; cytotoxicity; arsenite; caspases; Pakistan Responsible Editor: Amin Bredan, VIB Inflammation Research Center & Ghent University, Belgium (Published: 27 April 2015) Citation: Libyan J Med 2015, 10 : 26875 - http://dx.doi.org/10.3402/ljm.v10.26875