Changes in the Calorimetric Value and Ignition Temperature of Composite Solid Propellants During Ageing-A Note

Calorimetric value and ignition temperature of carboxy terminated polybutadiene/ammonium perchlorate propellant decrease during accelerated ageing. The behaviour has been explained on account of binder loss and condensed phase reactions in the propellant matrix

Soil Quality Variation under Different Land Use Types in Haramosh Valley, Gilgit, Pakistan

Soil quality is a fundamental component of environmental quality and impact of land use is also a keydetrimental factor in today’s rapid urbanization era. The study aims to evaluate the effects of different land-use type on selected soil quality indicators. Sixty soil samples were collected from various land use types, i.e, pasture, forest and agriculture from a depth of 0-15cm. Analysis of variance (ANOVA) showed that the land use type significantly affected the soil’s physical and chemical properties. The moisture content was significantly higher (p<0.001) in the pasture (41.7%) than the forest (26.2%) and lowest in agricultural land (14.4%). The soil pH was significantly higher or slightly alkaline for agriculture (7.8), while for pasture (6.5) and forest (6.1), it was found to be slightly acidic. Electric conductivity (EC) and bulk density (BD) did not vary significantly with land use type, but the EC followed the decreasing order: forest (203.7μS/cm) < pasture (235μS/cm) < agriculture (328.7μS/cm). The soil organic matter (SOM) and soil organic carbon (SOC) significantly (p<0.05) differed with land use type and found in the order: forest (3.0%, 1.3 %) > pasture land (2.9%, 1.2%) > arable land (2.5%, 1.1%). NO3-N, available P and exchangeable K did not vary significantly across land use types. However, mean values were higher for agriculture (10.2mg/kg, 4.5mg/kg, 66mg/kg) than forest (10mg/kg,3.5mg/kg, 60mg/kg) and pasture (9.8mg/kg, 4.3, 60.2mg/kg). Alpine soils are good ecological indicators because of vulnerability to environmental change, therefore, regular monitoring of soil properties along with carbon stocks is essential to maintain soil health, enhance agricultural productivity and sustain agroecosystems

Substantial and sustained reduction in under-5 mortality, diarrhea, and pneumonia in Oshikhandass, Pakistan : Evidence from two longitudinal cohort studies 15 years apart

Funding Information: Study 1 was funded through the Applied Diarrheal Disease Research Program at Harvard Institute for International Development with a grant from USAID (Project 936–5952, Cooperative Agreement # DPE-5952-A-00-5073-00), and the Aga Khan Health Service, Northern Areas and Chitral, Pakistan. Study 2 was funded by the Pakistan US S&T Cooperative Agreement between the Pakistan Higher Education Commission (HEC) (No.4–421/PAK-US/HEC/2010/955, grant to the Karakoram International University) and US National Academies of Science (Grant Number PGA-P211012 from NAS to the Fogarty International Center). The funding bodies had no role in the design of the study, data collection, analysis, interpretation, or writing of the manuscript. Publisher Copyright: © 2020 The Author(s).Peer reviewedPublisher PD

Trends in Use of Referral Hospital Services for Care of Sick Newborns in a Community-based Intervention in Tangail District, Bangladesh

The Projahnmo-II Project in Mirzapur upazila (sub-district), Tangail district, Bangladesh, is promot\uading care-seeking for sick newborns through health education of families, identification and referral of sick newborns in the community by community health workers (CHWs), and strengthening of neo\uadnatal care in Kumudini Hospital, Mirzapur. Data were drawn from records maintained by the CHWs, referral hospital registers, a baseline household survey of recently-delivered women conducted from March to June 2003, and two interim household surveys in January and September 2005. Increases were observed in self-referral of sick newborns for care, compliance after referral by the CHWs, and care-seeking from qualified providers and from the Kumudini Hospital, and decreases were observed in care-seeking from unqualified providers in the intervention arm. An active surveillance for illness by the CHWs in the home, education of families by them on recognition of danger signs and counsel\uadling to seek immediate care for serious illness, and improved linkages between the community and the hospital can produce substantial increases in care-seeking for sick newborns

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Studies on the ageing behaviour of polyvinylchloride/ammonium perchlorate composite solid propellant

The effects of ageing on the properties of a complete polyvinyl chloride - dibutyl phthalate - ammonium perchlorate solid propellant have been studied by measurements of burning rates, thermal decomposition rates (by thermogravimetry and DTA) and calorimetric values. Ageing leads to loss of HCl by dehydrochlorination and a corresponding increase in heat of combustion

Significance of Pretreatment in Enhancing the Performance of Dry Anaerobic Digestion of Food Waste: An Insight on Full Scale Implementation Strategy with Theoretical Analogy

The aim of this study was to treat food waste containing 25% total solids (TS) through dry anaerobic digestion (dry AD) process at various pressures (0.5 to 2.5 kg/cm2) and different time duration (20 to 100 min) to understand the impact of pretreatment in enhancing the methane generation potential along with insights on scale up. The findings revealed that vs. reduction and methane yield of 60% and 0.25 L CH4/(g VSadded) can be achieved with pretreated food waste at two kilograms per square centimeter, while pretreatment of food waste at 2 kg/cm2 for 100 min enhanced the vs. reduction from 60% to 85% and methane yield from 0.25 to 0.368 L CH4/(g VSadded). However, the net energy indicated that 40 min of pre -treatment at two kilograms per square centimeter can be a suitable option as methane yield and vs. reduction of 0.272 L CH4/(g VSadded) and 70%, respectively was achieved. The vs. reduction and the methane yield of 45% and 0.14 L CH4/(g VSadded), respectively was obtained from untreated food waste which illustrated that pretreatment had significantly impacted on the enhancement of methane generation and organic matter removal which can make the dry AD process more attractive and feasible at commercial scale

Changes in the calorimetric value and ignition temperature of composite solid propellants during ageing

Calorimetric value and ignition temp. of carboxy-terminated polybutadiene$/NH_4ClO_4$ propellant decrease during accelerated aging. The behavior is attributed to binder loss and condensed phase reactions in the propellant matri

Calorimetric values of composite solid propellants

The calorimetric values of composite solid propellant based on polystyrene, polyphenolformaldehyde, poly(vinyl chloride) and carboxy-terminated polybutadiene were determined using combustion calorimetry in order to assess the uncertainities in their measurements. The dependence of the calorimetric values on various propellant composition was obtained. The stoichiometry of oxidizer and fuel in the propellant for complete combustion obtained experimentally were compared with the theoretical stoichiometry calculated based on the oxidizer decomposition

Calorimetric values of composite solid propellants

The calorimetric values of composite solid propellant based on polystyrene, polyphenolformaldehyde, poly(vinyl chloride) and carboxy-terminated polybutadiene were determined using combustion calorimetry in order to assess the uncertainities in their measurements. The dependence of the calorimetric values on various propellant composition was obtained. The stoichiometry of oxidizer and fuel in the propellant for complete combustion obtained experimentally were compared with the theoretical stoichiometry calculated based on the oxidizer decomposition