Numerical Expedition on the Potential of AgBiS2-Based Thin Film Solar Cells Employing Different Carrier Transport Layers.

In this study, a photovoltaic (PV) device has been developed by using AgBiS2 as the key material. The simulation of the photovoltaic cell has been performed using the SCAPS-1D simulator to analyze the impact of each layer. The design incorporates three window layers, CdS, In2S3, and ZnSe, alongside six familiar compounds, AlSb, CuGaSe2 (CGS), CuS, MoS2, Sb2S3, and WSe2, as the back surface field (BSF) layers. These heterostructures aim to uncover the potential of AgBiS2 in the realm of photovoltaic technology. When AgBiS2 functions within a singular heterojunction, specifically in configurations such as n-CdS/p-AgBiS2, n-In2S3/p-AgBiS2, and n-ZnSe/p-AgBiS2, the resulting values for open-circuit voltage (V OC) and the short circuit current (J SC) are found to be ∼0.90 V and ∼32 mA/cm2, respectively, while the corresponding power conversion efficiencies (PCE) are 23.56%, 22.60%, and 23.62%, respectively. On the contrary, the incorporation of various BSF layers like AlSb, CGS, CuS, MoS2, Sb2S3, and WSe2 results in a substantial increase in V OC, leading to an enhancement in PCE. Among the AgBiS2 based different dual-heterostructures, the outstanding PCE of 30.04% with a V OC of 1.12 V is achieved by n-ZnSe/p-AgBiS2/p+-Sb2S3 device. In comparison, the n-ZnSe/p-AgBiS2/p+-CGS structure exhibits a similar PCE of 30.03% with a V OC of 1.12 V. Additionally, the n-ZnSe/p-AgBiS2/p+-MoS2 arrangement demonstrates a PCE of 29.95% and a V OC of 1.12 V. The effective band alignments observed at the interfaces of ZnSe/AgBiS2 and AgBiS2/MoS2, ZnSe/AgBiS2 and AgBiS2/CGS, as well as ZnSe/AgBiS2 and AgBiS2/Sb2S3 contribute to a substantial built-in potential, leading to an elevated V OC. As an alternative to ZnSe, the CdS window could offer similar performances, whereas In2S3 might provide a lower efficiency. The elaborate simulation findings highlight the substantial potential of AgBiS2 as an absorber, particularly when coupled with different windows and BSF layers. This opens avenues for experimental research focused on AgBiS2 in the era of photovoltaic cells.

Difference in presentation, outcomes, and hospital epidemiologic trend of COVID-19 among first, second, and third waves in Dhaka Medical College

BackgroundThis study aimed to examine the differences in epidemiologic and disease aspects among patients with COVID-19 MethodsWe reviewed the hospital records between April 2020 and September 2021 and followed up on the patients for post-COVID complications. FindingsOlder adult patients were predominantly affected during the first and second waves, followed by middle-aged patients. Men were predominantly admitted, considering the three waves; although more women were admitted in the second wave. Cough was more common in the second and third waves than in the first wave 522 (59.7%). Respiratory distress was the most common in the third wave, 251(67.1%), and least common in the first wave 403 (46.1%). Anosmia was more common in the third wave 116 (31.2%). In the third wave, patients presenting in a critical state 23 (6.2%) and severe disease 152 (40.8%) were more common. The hospital admission median (IQR) was longer in the first wave, 12 (8-20), than in other waves. More patients were admitted in the first wave (52%) than in the other waves, and patients received more oxygen in the third wave (75%) than in the other waves. Death occurred more commonly in the first wave (51%) than in the other waves. Patients were investigated more commonly in the first and third waves than in the second wave. The positivity rate was high in the third wave (22.8%) than in other waves. In the third wave, the positivity rate was higher in women (24.3%) than in men. Post-covid cough increased in the second wave and fatigue was higher in the third wave than in other waves. Tiredness and memory loss was greater during the second wave than in other waves. ConclusionThis study revealed that the presenting symptoms, outcomes, and epidemiologic trends differed during the COVID-19 waves.

Prevalence of mental health symptoms and its effect on insomnia among healthcare workers who attended hospitals during COVID-19 pandemic: A survey in Dhaka city.

BACKGROUND: During the COVID-19 pandemic, the high workload, risk of infection, and safety issues for family members may pose a threat to the mental health of healthcare workers (HCWs) working in hospital settings. The study aimed to find out the prevalence of anxiety, depression, and insomnia symptoms were among HCWs, as well as the factors related to these mental health issues. METHODS: We conducted an online survey of HCWs employed in Dhaka city from June 6 to July 6, 2020. Symptoms of anxiety, depression, and insomnia were measured using the Generalized Anxiety Disorder, the depression module of the Patient Health Questionnaire, and the Insomnia Severity Index, respectively. The related factors of anxiety, depression, and insomnia symptoms were identified using three regression models. RESULTS: This research included responses from 294 HCWs (mean ± standard deviation age: 28.86 ± 5.5 years; 43.5% were female). Anxiety, depression, and insomnia symptoms were found in 20.7%, 26.5%, and 44.2% of HCWs, respectively. The variable financial difficulties was commonly found as an associated factor for anxiety, depression, and insomnia symptoms. Female HCWs were more prone to mental health symptoms and insomnia compared to male HCWs (Adjusted odds ratio- AOR = 2.20, 95% CI = 1.27-3.79). The depression symptoms among HCWs were found to be a factor for insomnia (AOR = 6.321, 95% CI = 3.158-12.650). CONCLUSION: In the current pandemic, the high prevalence of mental health symptoms among HCWs indicates that this occupational group being associated with increased mental distress. Increasing financial support for HCWs and providing support to female workers in care facilities could help to alleviate the burden of mental illness. Supportive, training, and educational strategies, particularly through knowledge and communication platforms, could be recommended to the care facilities, which can reduce the burden of mental health symptoms among HCWs.

Integrative Analysis of lncRNA-mRNA Coexpression in Human Lung Epithelial Cells Exposed to Dimethyl Selenide-Derived Secondary Organic Aerosols.

Dimethyl selenide (DMSe) is one of the major volatile organoselenium compounds released into the atmosphere through plant metabolism and microbial methylation. DMSe has been recently revealed as a precursor of secondary organic aerosol (SOA), and its resultant SOA possesses strong oxidizing capability toward thiol groups that can perturb several major biological pathways in human airway epithelial cells and is linked to genotoxicity, DNA damage, and p53-mediated stress responses. Mounting evidence has suggested that long noncoding RNAs (lncRNAs) are involved in stress responses to internal and environmental stimuli. However, the underlying molecular interactions remain to be elucidated. In this study, we performed integrative analyses of lncRNA-mRNA coexpression in the transformed human bronchial epithelial BEAS-2B cell line exposed to DMSe-derived SOA. We identified a total of 971 differentially expressed lncRNAs in BEAS-2B cells exposed to SOA derived from O3 and OH oxidation of DMSe. Gene ontology (GO) network analysis of cis-targeted genes showed significant enrichment of DNA damage, apoptosis, and p53-mediated stress response pathways. trans-Acting lncRNAs, including PINCR, PICART1, DLGAP1-AS2, and LINC01629, known to be associated with human carcinogenesis, also showed altered expression in cell treated with DMSe-SOA. Overall, this study highlights the regulatory role of lncRNAs in altered gene expression induced by DMSe-SOA exposure.

ReCoNet: Multi-level Preprocessing of Chest X-rays for COVID-19 Detection Using Convolutional Neural Networks

Life-threatening COVID-19 detection from radiomic features has become a dire need of the present time for infection control and socio-economic crisis management around the world. In this paper, a novel convolutional neural network (CNN) architecture, ReCoNet (residual image-based COVID-19 detection network), is proposed for COVID-19 detection. This is achieved from chest X-ray (CXR) images shedding light on the preprocessing task considered to be very useful for enhancing the COVID-19 fingerprints. The proposed modular architecture consists of a CNN-based multi-level preprocessing filter block in cascade with a multi-layer CNN-based feature extractor and a classification block. A multi-task learning loss function is adopted for optimization of the preprocessing block trained end-to-end with the rest of the proposed network. Additionally, a data augmentation technique is applied for boosting the network performance. The whole network when pre-trained end-to-end on the CheXpert open source dataset, and trained and tested with the COVIDx dataset of 15,134 original CXR images yielded an overall benchmark accuracy, sensitivity, and specificity of 97.48%, 96.39%, and 97.53%, respectively. The immense potential of ReCoNet may be exploited in clinics for rapid and safe detection of COVID-19 globally, in particular in the low and middle income countries where RT-PCR labs and/or kits are in a serious crisis.

Prevalence of extended spectrum beta-lactamase (ESBL) and AmpC beta-lactamase producing bacteria in urinary tract infection patients in Bangladesh

Aims@#This study aimed to determine the prevalence of pathogens in urinary tract and their antimicrobial susceptibilities, based on extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase production in Bangladesh. @*Methodology and results@#The prevalence of pathogenic microorganisms in urinary tract and their antimicrobial resistance patterns were identified in 200 isolates from patients with urinary tract infections. Combined disc diffusion was performed to identify the presence of ESBL-producing strains. Moreover, disc approximation assay, disc potentiation test and double disc synergy test were performed to determine the presence of AmpC beta-lactamase producing bacterial strains. This study demonstrated a higher prevalence of UTIs in females (83.5%) than in males (16.5%). The most common pathogen was found Escherichia coli (44.5%), followed by Enterococcus fecalis (24%), Klebsiella pneumoniae (7.5%), Staphylococcus aureus (6%), Pseudomonas aeruginosa (5.5%) and Staphylococcus saprophyticus (4.5%). ESBL and AmpC beta-lactamase production occurred more frequently in E. coli (25.84%) and P. aeruginosa (100%) respectively. @*Conclusion, significance and impact of study@#The result of this study would provide physicians with important information which help them to make a judicious choice of antibiotics for therapeutic purposes. However, it is emphasized that continuous surveillance of antibiogram of medically important organisms causing UTI is necessary for adopting a rational antibiotic policy in the country.

Calculation of the uncertainty in the activity estimate for workers in the uranium industry.

This paper describes a methodology to calculate the uncertainty that may propagate during the uranium activity estimation for workers. An analytical expression was derived to find a relationship between measured activity and the chest wall thickness that is routinely measured for workers. The uncertainty in activity estimation was empirically calculated for 14 workers using their measured chest wall thicknesses collected over a 5 y time period.

Radiation protection for accompanying person and radiation workers in PET/CT.

The purposes of the present study are to measure the total radiation doses for the radiation workers and for the accompanying person to the patients in positron emission tomography (PET)/computed tomography (CT) imaging. Urines samples from the patients were collected at 43, 62, 87, 117, 238, 362 min after the 555-MBq (18)flour-fluorodeoxyglucose ((18)F-FDG) injection and activities were measured. Dose rates were recorded using a Geiger-Muller counter and the total radiation doses were measured with using an electronic personnel dosemeter. According to the results here, 18.4 % of (18)F-FDG was excreted in the urine in 117 min after injection. At 117th min after injection, dose rates were determined as 345, 220, 140, 50 and 15 µSv h(-1), at proposed distances. The radiation doses after 117 min were measured as 3.92 mSv at 0.1 m, 2.11 mSv at 0.25 m and 1.08 mSv at 0.5 m. In conclusion, radiation protection will be sufficient within 2 h after (18)F-FDG injection for PET/CT imaging in daily practice.

Diarrhea and ARI in rural areas of Bangladesh.

In Bangladesh, one third of the total child death burden is due to diarrhea. Every year, a rural child suffers on average from 4.6 episodes of diarrhea, from which about 230,000 children die. In this study, information was collected from 8,287 children under five years of age and 7,082 caretakers in 120 clusters chosen by a two-stage random cluster sampling method. As compared to the baseline survey, carried out in 1996, children now are about 30% less likely to suffer from diarrhea, and the risk of dying has been reduced by 60%. Although the 2-weeks prevalence of acute respiratory infection (ARI) has risen from 39% (1996) to 46% and that of Acute Respiratory Infections needing assessment (ANA) from 12.4% to 16.9%, now more caretakers (59.9%) than in 1996 (56.7%) are able to identify correctly danger signs for seeking care and 58.4% (1996: 46.6%) of parents seek help when danger signs are present. Similar for diarrhea and ARI, village doctors and traditional healers are most frequently sought for help by caretakers; government health centers and hospitals are sought to a much lesser degree. Since 1996, intervention activities were implemented for four years in the study area using an IEC strategy. This strategy included raising awareness and training of health personnel, NGO personnel and village volunteers, especially women. Diarrhea issues were included in school health education with emphasis on practical exercises of diarrhea management. For all target groups (health personnel, village volunteers, NGOs, mothers and school children) specific education material was developed and deployed. In the political arena, women leaders who are part of the local government were included in an awareness-raising campaign. The results of the study undertaken over four years later show that in a relatively short time behavior of mostly poor and illiterate caretakers can be changed leading to a significant reduction of ARI mortality and diarrhea morbidity, and mortality in children.

Quantification of absorbed doses to urine bladder depending on drinking water during radioiodine therapy to thyroid cancer patients: a clinical study using MIRDOSE3.

The object of the study was to quantify the absorbed doses to urinary bladder using MIRDOSE3 (medical internal radiation dose package program) depending on drinking water after giving radioiodine dose to thyroid cancer patients. Twenty-nine female thyroid cancer patients (aged 40-60 years, mean 50 years) were selected. The therapeutic doses ranged from 3700 to 7400 MBq of 131I. The radioiodine uptake was measured at 1 cm distance from three organs (previously marked), the thyroid, thigh and stomach, by using a calibrated Eberline ESP-2 GM counter, with a special arrangement of each patient. Urine samples were collected every 12 h for first 72 h, and then every 24 h for the next 96 h. The individual biological half-life of excreted urine was calculated using individual effective half-life. Absorbed doses were calculated for an adult female phantom using the dynamic bladder model of MIRDOSE3 program in two phases: firstly, for different voiding intervals; and secondly, depending on individual drinking water. An average of 85% of the total dose passed through the urinary tract within the first 72 h, with a biological half-life of 28.5+/-0.747 h, and 9% for the next 96 h with a biological half life of 118.43+/-0.645 h. The voiding interval shows great impact on total absorbed dose to bladder and water supplementation needs to be intensified to reduce absorbed doses to bladder wall for the first 3 days.