The study area was selected in the Rupsha river basin and the sediment samples were collected to determine trace metal concentrations of As, Pb, Cd, and Cr along with biological effects, and potential ecological and human health hazards for adults and children. The concentrations of trace metals were detected from sixty composite sediment samples using an Atomic Absorption Spectrophotometer (AAS) following some sequential analytical procedures. The mean concentrations of trace metals were organized in the descending order of chromium (Cr) (43.2 mg/kg) > lead (Pb) (29.21 mg/kg) > arsenic (As) (5.18 mg/kg) > cadmium (Cd) (1.8 mg/kg). The current study highlighted that metals were attributed to the riverine sediments from natural sources and other anthropogenic sources, particularly from various industries. Based on the effect-range classifications of threshold effect concentration (TEC) and probable effect concentration (PEC), the trace metal concentrations can impact on the sediment-dwelling organisms occasionally especially for Cr, Cd, and Pb. That is, the concentrations had negative biological consequences on aquatic creatures. The assessed potential ecological risk of Cd offers a significant risk to the aquatic ecosystem, whereas As, Cr, and Cd were in low-risk. Most of the sites of the study area were within the range of moderate risk, indicated by the risk index (RI) values. Furthermore, the applied sediment quality indices, geo-accumulation index (Igeo) indicated that sediment was contaminated by Cd whereas contamination factor (CF) denoted that the sediment of the study area was moderately polluted by Pb. However, pollution load index (PLI) revealed that the study area was polluted for cumulative sence especially in winter season. The age-group risk index (HI) was much lower than the threshold limit of 1, showing that the pollution had no non-carcinogenic risk effect. Total carcinogenic risk (TCR) was less than one-tenth of a percentile. For the sake of human and environmental health, proper monitoring of metal element attribution and strict regulation are required to lessen trace metal pollution.

Based on the first-principles density functional theory, Janus WXY (X ≠ Y = S, Se, and Te) trilayer homostructures for different stacking patterns are studied in this work to analyze their appropriateness in fabricating photovoltaic (PV) devices. A total of fifteen trilayer homostructures are proposed, corresponding to the suitable five stacking patterns, such as AAA, AA′A, ABA, AB′A, and A′BA′ for each Janus WXY (X ≠ Y = S, Se, and Te) material. Structural and energetic parameters for all the fifteen structures are evaluated and compared to find energetically stable structures, and dynamic stability is confirmed by phonon dispersion curves. All these configurations being homostructure, lattice mismatch is found to be very low (∼0.05%), unlike heterostructure, making them feasible for optoelectronics and PV applications. WSSe AAA, WSSe AA′A, and WSeTe AA′A are dynamically stable along with negative binding energy and show type-II band alignment, enabling effective spatial carrier separation of photogenerated carriers. The optical properties of dynamically stable WSSe AAA and WSSe AA′A structures are also calculated, and the absorption coefficients at the visible light region are found to be ∼3.5 × 10 5 cm –1 , which is comparable to the perovskite material absorption coefficient. Moreover, we have compared the optical characteristics of dynamically stable WSSe AAA and WSSe AA′A structures with their monolayer structures to realize the significance of stacking trilayer structures. Electrical properties such as mobility and conductivity for dynamically stable WSSe AAA and WSSe AA′A structures are evaluated to suggest them as a probable efficient material in PV technology.

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Introduction: Caudal epidural anesthesia, when used as a sole method for surgical anesthesia, has favorable effects on the recovery duration and the time spent in the recovery unit. Aim of the Study: The aim of this retrospective study was to assess the efficacy of caudal epidural block for postoperative pain in children in a tertiary care hospital. Methods: The retrospective study was conducted in the Department of Paediatrics Anaesthesiology, Surgical ICU in Bangladesh Shishu Hospital & Institute; during the period of 1st January 2022 to 30th June 2022. A total 60 patients were selected as study people purposively with the permission of the Hospital Ethics Committee and the informed consent from the parents of the children. Result: A total 60 study patients were selected for this study. 30 patients had given lignocaine (Group-1) and the rest 30 patients had given bupivacaine (Group-2). According to the grading of the children who were administered in two groups good result found in group-2 and it was about 21(70.00%). Maximum fair result 11(36.67%) followed in group-1. The mean of pain duration of children who were administered lignocaine (Group I) was found 7.10±3.35 and bupivacaine (Group II) was found 14.65±2.85. Both data were statistically significant (<0.0001). Conclusion: By understanding the various surgical conditions for caudal analgesia, we conclude that caudal block is a good and safe technique for paediatric patients.

Introduction: The effectiveness of dexamethasone (DEX) in reducing complication rates following paediatric tonsillectomy is still up for debate. The incidence of postoperative nausea and vomiting (PONV) and the severity of pain following paediatric tonsillectomy were examined by comparing concentrations of DEX 0.15 and DEX 0.5 mg/kg, respectively. Aim of the study: The aim of the study is to assess the effect of Dexamethasone in management of postoperative nausea, vomiting and pain after tonsillectomy where the targeted patients are of 3 to 10 years children. Methods: This prospective cross sectional study was conducted in the Department of Paediatric Anaesthesiology and Surgical ICU in Bangladesh Shishu Hospital and Institute, Dhaka, Bangladesh during July 2019 to June 2022. This study included 123 children undergoing elective tonsillectomy. The Institutional Ethics Committee approved this study and informed parental written consent was obtained from the parents before collecting the patients’ information. Results: The prevalence of early PONV was lower in both DEX groups (DEX 0.15: 22%; DEX 0.5: 26%; placebo: 48%; P=0.001). On the second day after surgery, the DEX groups had a lower rate of severe pain (DEX 0.15: 20%; DEX 0.5: 5%; placebo: 47%; P<0.001). The study was not conducted to assess a difference between the two dose groups of Dexamethasone. Conclusions: The frequency of early and late PONV and the level of pain on the second postoperative day were both reduced by an i.v injection of DEX during the induction of anesthesia. To reduce the incidence of PONV, it appeared that a dose of DEX 0.15 mg/kg was just as effective as a dose of DEX 0.5 mg/kg.