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Lauren B. Kleimola Archana B. Patel Jitesh A. Borkar Patricia L. Hibberd 《International journal of occupational and environmental health》2015,21(4):294-302
Background: Over one-third of the world’s population is exposed to household air pollution (HAP) but the separate effects of cooking with solid fuel and kerosene on childhood mortality are unclear.Objectives: To evaluate the effects of both solid fuels and kerosene on neonatal (0-28 days) and child (29 days-59 months) mortality.Methods: We used Demographic and Health Surveys from 47 countries and calculated adjusted relative risks (aRR) using Poisson regression models.Results: The aRR of neonatal and child mortality in households exposed to solid fuels were 1.24 (95% CI: 1.14, 1.34) and 1.21 (95% CI: 1.12, 1.30), respectively, and the aRR for neonatal and child mortality in households exposed to kerosene were 1.34 (95% CI: 1.18, 1.52) and 1.12 (95% CI: 0.99, 1.27), controlling for individual, household, and country-level predictors of mortality.Conclusions: Kerosene should not be classified as a clean fuel. Neonates are at risk for mortality from exposure to solid fuels and kerosene. 相似文献
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64.
The concentrations and distributions of the activity of natural radionuclides in soil samples were investigated in fifteen soil samples at El-Gor area representing two profiles (A and B) using a HP–Ge detector and alpha counting by SSNTD (CR-39), respectively. The average concentrations of the radionuclides 238U, 226Ra, 235U, 232Th and 40K are 203.4, 177.23, 9.77, 43.33 and 386.22 Bq kg−1 (dry weight), respectively, and profile A and 238U, 226Ra, 235U, 232Th and 40K have average concentrations of 232.58, 246, 11.7, 31.7, and 277.07 Bq kg−1 for profile B, respectively. The eTh and eU were estimated to detect the migration process of uranium into or out of an area or uranium to or from the studied profiles. The results indicate a migration of uranium by 29% for profile A and 65.37% for profile B. The activity ratio (238U/226Ra) was found to be 0.9 in profile A and 1.15 in profile B. These ratios coincide with the uranium migration processes. The responsible mass corresponding to the measured 226Ra activity was also calculated. The radon activity concentrations for the two profiles are nearly 300 Bq m−3. The emanation coefficient (η) was calculated from the ratio of the expected radon activity to the measured radon for the studied soil samples. The value of η was found to depend only on the radium activity regardless to soil formation. 相似文献
65.
66.
Muna Shrestha Helen Shi Mark Strohmeier Ales Medek 《Journal of pharmaceutical sciences》2021,110(4):1592-1600
Physical or chemical interactions between drug product (DP) components can occur during manufacturing and/or upon storage; and may alter DP shelf life and performance. In this work a new Powder X-ray Diffraction (PXRD) peak was observed in DP under accelerated storage conditions. Due to the complex drug product matrix (including API, polymer, fillers, super disintegrant and lubricant), it was challenging to pinpoint the component(s) responsible for the new peak. In addition to PXRD, other orthogonal techniques including Differential Scanning Calorimetry (DSC), thermogravimetric analysis (TGA), dynamic vapor sorption (DVS), Solid State Nuclear Magnetic Resonance (SSNMR) and Infrared (IR) spectroscopy were employed in this investigation to understand the root cause mechanistically. Specifically, multi nuclei SSNMR (1H, 23Na, 13C) was instrumental in delineating the components of the matrix. We identified the root cause to be an acid base reaction occurring in the DP, whereby sodium ion in sodium stearyl fumarate (SSF) is replaced by proton leading to SSF form conversion. We also identified commercially available SSF to be a hydrate that can dehydrate to an anhydrous form upon heating. In general, the same techniques can be used to investigate interactions of any multi component solid dosage forms. 相似文献
67.
Allogeneic hematopoietic stem cell transplantation (alloHSCT) produces –similar to the long-established graft-versus-leukemia effect– graft-versus-solid-tumor effects. Clinical trials reported response rates of up to 53%, occurring mostly but not invariably in association with full donor chimerism and/or graft-versus-host disease. Although donor-derived T cells are considered the principal effectors of anti-tumor immunity after alloHSCT or donor leukocyte infusion (DLI), growing evidence indicate that recipient-derived immune cells may also contribute. Whereas the role of recipient-derived antigen-presenting cells in eliciting graft-versus-host reactions and priming donor T cells following DLI is well known, resulting inflammatory responses may also break tolerance of recipient effector cells towards the tumor. Additionally, mouse studies indicated that post-transplant recipient leukocyte infusion produces anti-leukemia and anti-solid-tumor effects that were exclusively mediated by recipient-type effector cells, without graft-versus-host disease. Here, we review current preclinical and clinical evidence on graft-versus-solid-tumor effects and growing evidence on the effector role of recipient-derived immune cells in the anti-tumor effect of alloHSCT. 相似文献
68.
Nurul Absar M. Mashiur Rahman Masud Kamal Naziba Siddique Mantazul Islam Chowdhury 《Journal of radiation research》2014,55(6):1075-1080
Radioactivity in the soil of a tea garden in the Fatickchari area in Chittagong, Bangladesh, was measured using a high-resolution HPGe detector. The soil samples were collected from depths of up to 20 cm beneath the soil surface. The activity concentrations of naturally occurring 238U and 232Th were observed to be in the range of 27 ± 7 to 53 ± 8 Bq kg−1 and 36 ± 11 to 72 ± 11 Bq kg−1, respectively. The activity concentration of 40K ranged from 201 ± 78 to 672 ± 81 Bq kg−1, and the highest activity of fallout 137Cs observed was 10 ± 1 Bq kg−1. The average activity concentration observed for 238U was 39 ± 8 Bq kg−1, for 232Th was 57 ± 11 Bq kg−1, for 40K was 384 ± 79 Bq kg−1 and for 137Cs was 5 ± 0.5 Bq kg−1. The radiological hazard parameters (representative level index, radium equivalent activity, outdoor and indoor dose rates, outdoor and indoor annual effective dose equivalents, and radiation hazard index) were calculated from the radioactivity in the soil. 相似文献
69.
The response of a semiconductor alpha detector to fast (>1 MeV) neutrons was investigated by using measurements and simulations. A polyethylene converter was placed in front of the detector to register recoil protons generated by elastic collisions between neutrons and hydrogen nuclei of the converter. The developed prototype equipment was tested with shielded radiation sources. The low background of the detector and insensitivity to high-energy gamma rays above 1 MeV are advantages when the detection of neutron-emitting nuclear materials is of importance. In the case of a 252Cf neutron spectrum, the intrinsic efficiency of fast neutron detection was determined to be 2.5×10−4, whereas three-fold greater efficiency was obtained for a 241AmBe neutron spectrum. 相似文献
70.
介绍了CT机的性能及运行状态在临床诊断中的重要性,分析了CT机各部件的监测与维护特点。应用CT核心组件持续监测总结法,解决了CT机的性能及运行状态监测非系统化的问题,为医院掌握CT机的实时性能状况提供了有力的依据,保障了设备准确稳定地运行。 相似文献