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This study investigates the dynamic response of RC lined rectangular tunnel in soil subjected to internal blast load. For this purpose, a three-dimensional non-linear finite element model comprising of tunnel lining, reinforcement, and soil is analyzed in Abaqus/Explicit. The behaviors of soil, concrete, and steel are simulated using Drucker-Prager plasticity, concrete damaged plasticity, and Johnson–Cook (J-C) plasticity models, respectively. The effect of various grades of concrete (C30, C40, and C50) and lining thickness (300 mm, 400 mm, and 500 mm) on the dynamic response of the tunnel structure and the surrounding soil is investigated. It is observed from the results that deformations of tunnel lining increase with a decrease in the grade of concrete and decrease with an increase in lining thickness. The results suggest it is advantageous to increase the thickness of the liner for a certain grade of concrete, rather than increasing the grade of concrete for the same liner thickness for better blast response. The vulnerability of the tunnel liner is high at the roof-sidewall junction suggesting the need for better reinforcement detailing.

The present study was conducted to assess the groundwater hydrogeochemistry of the Majuli River Island in the Brahmaputra river basin. Forty-three groundwater samples were collected from shallow aquifers from different sites in the Majuli River basin, and various physicochemical parameters of the samples were analyzed. The study showed that nearly 27%, 79.06%, 88.37%, and 74.41% of groundwater samples had higher nitrate, total hardness, iron, and manganese content, respectively, than the acceptable limits of the Bureau of Indian Standards (BIS) for drinking water. The water quality index revealed that 72% of samples were not at all suitable for human drinking purpose. The piper trilinear plot showed that the groundwater could be classified as mixed water, i.e., Ca–HCO3, Ca–Mg–HCO3and Mg–Ca–HCO3, based on the cation and anion concentration. For analyzing the corrosiveness and scaling potential of the groundwater, the Langelier saturation index (LSI), Ryznar stability (RSI), Puckorius scaling (PSI), Larson Skold index (LaI), and chloride sulphate mass ratio (CSMR) were computed. The Ryznar index value of 70% collected groundwater samples was found to be more than 7.0, depicting significant corrosion towards the groundwater. Similarly, 90.69% samples had PSI value >6.5, representing a tendency for corrosion. A total of 70% and 95.34% of the groundwater samples were corrosive in nature based on the LaI and CSMR index values, respectively. Therefore, the indices revealed that that majority of groundwater samples of the Majuli River Island were corrosive in nature due to its non-alkaline characteristic and high iron content in the groundwater. The groundwater of the Majuli River Island may cause a detrimental impact on the domestic and industrial water quality and water distribution systems.

Purpose: Identifying ideal plasticizer is pivotal to develop a biopolymer-based edible films for food packaging. The effect of different plasticizers (glycerol, polyethylene glycol, sorbitol) on the mechanical, water vapor barrier, optical, and moisture sorption properties of hydroxypropyl methylcellulose (HPMC) -based flexible films was examined in this study. Methods: Mechanical properties and water vapor permeability (WVP) of films were determined using standard ASTM methods. Moisture sorption isotherm (MSI) for different HPMC films were obtained thermogravemitically and seven sorption models were fitted to experimental sorption data through nonlinear regression using curve fitting tool in MATLAB R2015b and goodness of fit of these models was compared based on Akaike information criterion (AIC). GAB model was used to determine the monolayer moisture content and heat of sorption of different films. Results: Plasticizing efficacy of different plasticizers was significantly different for HPMC film in studied concentration range. Water vapor permeability (WVP) for native HPMC film was 0.451 g mm/kPa m2h, which further increased to 0.972, 0.890, and 0.615 g mm/kPa m2h when 25% (w/w of HPMC) glycerol, PEG, and sorbitol were added as plasticizers, respectively. GAB model showed an increase in monolayer moisture (M0) content with increasing plasticizer concentration and the highest M0value was observed for glycerol-plasticized film. Conclusions: Added plasticizers were found to be effective in providing desirable flexibility in terms of elongation to HPMC film which is beneficial for coating and shrink wrap packaging application but adversely affect the tensile strength and transparency of film. Henderson and Oswin models were selected as the best fit model to the experimental sorption data based on AIC values. The findings from the current study would serve in selection of suitable plasticizer for HPMC-based film/coating in food packaging applications.

Background: Valproate is a widely prescribed medication for the control of seizures in the pediatric population. It has been reported to be an important implication for drug induced pancreatitis. A case of valproate induced acute pancreatitis operated as surgical abdomen has been reported here. Case Report: A 13-year-old child presented to the emergency department with severe pain and abdominal distension associated with vomiting and constipation for four days. The patients caregivers did not disclose any medication history. Based on clinical examination and ultrasonography that revealed mild free fluid, a provisional diagnosis of pyoperitoneum with peritonitis was made. An emergency exploratory laparotomy was undertaken during which acute pancreatitis was diagnosed intra-operatively. On further enquiry, the caregiver revealed the history of valproate intake for the last six months for generalized tonic-clonic seizures. Valproate was discontinued and there was complete resolution of symptoms. Conclusion: Both clinicians, as well as caregivers of paediatric patients receiving valproate, should be watchful regarding this possible life-threatening complication to avoid delay in diagnosis and appropriate management.

Acute kidney injury (AKI) may result from ischemic or toxic insult to renal tubular cells. The cellular damage involves several forms of injury: acute inflammatory response, sublethal damage, cell death through apoptosis and necrosis, and shedding of cells into the tubular lumen. The underlying mechanism of these different forms of injuries comprises of a complex interplay of inflammatory cytokines/chemokines, reactive oxygen species, and apoptotic factors. However, the kidney has a remarkable capacity to repair itself following AKI and thereby recover renal functions. The recovery process is associated with repopulation of damaged renal tubules by proliferation of tubular epithelial cells by several mechanisms.