DAM BREACH ANALYSIS AND PARAMETER SENSITIVITY ANALYSIS ALONG A RIVER REACH USING HECRAS

A dam break is a low-probability, high risk catastrophe event that is extremely destructive and has a substantial negative socio-economic impact on downstream and nearby areas. Simulating dam breach and analyzing flood propagation downstream from those events is vital for identifying and minimizing the risks associated downstream of dam location. This study is intended to anlayse the effect of overtopping failure of dam for two scenario  (a) base-case scenario (scenario with average value of dam breach parameters from their range) and (b) worst case scenario (the breach with largest geometry, shortest formation time and highest peak outflow magnitude). Further, a hydrodyanmic modelling is perfomed to  investigate  the sensitivity analysis (local and global) of five dam breach parameters (dam breach elevation, dam breach width, breach formation time, weir coefficient, trigger failure elevation) on breach outflow in a proposed hydropower project located in Nepal. Aeronautical Reconnaissance Coverage Geographic Information System (ArcGIS), Hydraulic Engineering Center River Analysis System (HEC-RAS) and OriginPro 2022b are utilized to analyse the effect of  dam breach and parameter sensitivity. Generation of outflow hydrograph shows that worst case scenario has devasting effect downstream with innudation of 1047 of househols and 50.83 kilometers of roads. The breach velocty was recorded as 15.16 m/s and 20.85 m/s for base and worst case respectively. The minimum depth and maximum depth of flooding downstream from dam location was found to be 24.51 m and 73.6 m for base case and 47.43 m and 106.75 m for worst case. Due to backwater effect at Bheri river, peak flow at 14 km downstream from dam reduces significantly to 124852.57 m3/s and 244204.41 m3/s for base and worst case respectively. From local sensitivty analysis it has been found that, dam breach elevation is more sensitive and triggering failure elevation is less sensitive for peak outflow hydrograph. Whereas, dam breach width seems more sensitive and TFE seems least sensitive for peak outflow using Monte Carlo Simulation for gloal sensitivity

Comprehensive Review on Multifaceted Carbon Dot Nanocatalysts: Sources and Energy Applications

In recent decades, several studies have been conducted on sustainability progress with high efficiency of renewable energies by utilizing advanced nano-module catalysts. Some collaborative studies advocate the unique characteristics of unconventional materials, including carbon nanotubes, nanosheets, nanoparticles, conducting polymers, integrated nano polymers, nano enzymes, and zero-dimensional nanomaterials/carbon dots (CDs) at the atomic and molecular level to generate efficient energy from various biomass substrates. Nanotechnology-based catalysts are considered a crucial tool for revolutionizing various energy-related applications. This review article addresses the sustainable and scarce biomass resources to synthesize CDs, properties, mechanisms, and insights with the advancement of research on CDs as nanocatalysts in the field of energy applications. These materials possess exceptional and rapidly expanding features such as being non-toxic, biocompatible, having excellent electrocatalytic activity and photoluminescence, and being highly dispersible in water. Because of these advantages, they are appealing for use in energy conversion and as storage material. Moreover, the emphasis is placed on the function of CDs as nanocatalysts for energy storage devices, and relevant instances are provided to clarify the concepts. These advanced strategies of nanotechnology for energy storage and conversion are expected to play a vital role in promoting sustainability

Varicella pneumonia in an immunocompetent child: A case report

Varicella-zoster virus (VZV) is a type of herpes virus that causes varicella (primary infection) and herpes zoster/shingles (due to reactivation of latent infection). Usually a benign and a self-limited illness, the illness sometimes can result in severe complications in both immunocompetent and immunocompromised persons. Varicella Pneumonia as a complication of herpes zoster is a rare event, with reports primarily concerning immunocompromised individuals. Here we report a 14-year-old female who developed a secondary bacterial infection of the skin lesions and varicella pneumonia associated with VZV infection. The patient presented with multiple painful vesicles that later turned into pustular lesions over the right cheek with erosions and hemorrhagic crusting. Swelling involving the right half of both upper and lower lips was present. She developed a fever, cough, and shortness of breath after two days of the presence of vesico-pustular lesions. A diagnosis of Pneumonia was made based on symptoms of fever and cough and findings on chest x-ray. This case highlights, though rare, varicella pneumonia has a high rate of respiratory failure, but early diagnosis with prompt administration of antiviral medications can improve outcomes

An association of Helicobacter pylori infection with endoscopic and histological findings in the Nepalese population

Background: Helicobacter pylori (H. pylori) is one of the most common human infections worldwide particularly in the developing countries. We aimed to study an association of H. Pylori infection with endoscopic and histological findings in the Nepalese population. Materials and Methods: We conducted a study between Oct 2014 and Jan 2015 after meeting inclusion and exclusion criteria. Institutional Review Board approval was obtained from National Academy of Medical Sciences. Endoscopic findings and histopathological diagnosis were documented and data were analysed. Results: A total of 113 patients who had complete endoscopy were enrolled. The prevalence of H. pylori infections recorded was 27 (23.9%) patients. There were 17 (62%) male and 10 (37%) female infected with H. pylori (P = 0.33). All biopsied specimens were sent to pathology lab for examination. The most common endoscopic findings was erythematous antral gastritis (40.7%) followed by erosive gastritis 34 (30.1%), pangastritis 10 (8.8%), duodenal ulcer 13 (11.5%), gastric ulcer 9 (8%), erosive fundal gastritis 2 (1.8%), reflux esophagitis 10 (37%) (P < 0.04). Histology revealed that 23 (85.2%) patients had chronic active gastritis (CAG); (P < 0.001). Conclusions: Our study revealed that H. pylori infection is strongly associated with chronic active gastritis (CAG) and Reflux esophagitis in Nepalese adults

Factors Predicting Mortality of Variceal Bleeding in Liver Cirrhosis

Introduction: Acute variceal bleeding in liver cirrhosis is an immediate life-threatening condition and amajor complication of portal hypertension associated with higher morbidity, mortality and hospital costs than any other causes of UGI bleeding. Therefore, early stratification and initiation of therapy based on several factors can reduce mortality associated with it. We aimed to study the predictors of mortality in acute variceal bleeding in LC. Methods: An observational prospective study was conducted in Gastroenterology and Hepatology units of Bir Hospital, Kathmandu, Nepal from April 1, 2016 to May 30, 2017. Patients were included if they had underlying liver cirrhosis and presented upper GI bleeding which were proven to be secondary to variceal bleeding. Results: Seventy-five patients with mean age of 52.5 years were available or the analysis. The M:F ratio was 2.1:1. There were 66 patients in mortality group and 9 in survivor group. The mean CTP and MELD score were 10.17±1.66 and 20.40±8.29 respectively. Among the predictors of the mortality studied, CTP score, MELD score, mean arterial pressure, Serum bilirubin, serum creatinine, need of FFP as well as PRP transfusion, presence of hepatorenal syndrome and hepatic encephalopathy were high in mortality group with statistical significance. On multivariate analysis, high CTP and high serum creatinine level were only significant predictors of mortality. Receiver operating curve for predicting accuracy of mortality was significant with higher MELD and higher CTP score. Conclusions: Strong predictors of mortality in patients with cirrhosis presenting with variceal bleeding are CTP score and high serum creatinine level