Histological and immunohistochemical evaluation of the effect of tartrazine on the cerebellum,submandibular glands,and kidneys of adult male albino rats

Environmental Science and Pollution Research - Tartrazine is one of the most widely used food additives. The present investigation was carried out on 40 adult male albino rats. They were divided...     

Beneficial role of ascorbic and folic acids antioxidants against thyroxin-induced testicular dysfunction in hyperthyroid rats

Environmental Science and Pollution Research - Thyroid hormones play a fundamental role in the regulation of metabolism of almost all mammalian tissue including the reproductive system....     

Hidden demographic impacts of fishing and environmental drivers of fecundity in a sea turtle population

Fisheries bycatch is a critical threat to sea turtle populations worldwide, particularly because turtles are vulnerable to multiple gear types. The Canary Current is an intensely fished region, yet there has been no demographic assessment integrating bycatch and population management information of the globally significant Cabo Verde loggerhead turtle (Caretta caretta) population. Using Boa Vista island (Eastern Cabo Verde) subpopulation data from capture–recapture and nest monitoring (2013–2019), we evaluated population viability and estimated regional bycatch rates (2016–2020) in longline, trawl, purse-seine, and artisanal fisheries. We further evaluated current nesting trends in the context of bycatch estimates, existing hatchery conservation measures, and environmental (net primary productivity) variability in turtle foraging grounds. We projected that current bycatch mortality rates would lead to the near extinction of the Boa Vista subpopulation. Bycatch reduction in longline fisheries and all fisheries combined would increase finite population growth rate by 1.76% and 1.95%, respectively. Hatchery conservation increased hatchling production and reduced extinction risk, but alone it could not achieve population growth. Short-term increases in nest counts (2013–2021), putatively driven by temporary increases in net primary productivity, may be masking ongoing long-term population declines. When fecundity was linked to net primary productivity, our hindcast models simultaneously predicted these opposing long-term and short-term trends. Consequently, our results showed conservation management must diversify from land-based management. The masking effect we found has broad-reaching implications for monitoring sea turtle populations worldwide, demonstrating the importance of directly estimating adult survival and that nest counts might inadequately reflect underlying population trends.     

Optimizing hydrogen production by alkaline water decomposition with transition metal-based electrocatalysts

Burning fossil fuels account for over 75% of global greenhouse gas emissions and over 90% of carbon dioxide emissions, calling for alternative fuels such as hydrogen. Since the hydrogen demand could reach 120 million tons in 2024, efficient and large-scale production methods are required. Here we review electrocatalytic water splitting with a focus on reaction mechanisms, transition metal catalysts, and optimization strategies. We discuss mechanisms of water decomposition and hydrogen evolution. Transition metal catalysts include alloys, sulfides, carbides, nitrides, phosphides, selenides, oxides, hydroxides, and metal-organic frameworks. The reaction can be optimized by modifying the nanostructure or the electronic structure. We observe that transition metal-based electrocatalysts are excellent catalysts due to their abundant sources, low cost, and controllable electronic structures. Concerning optimization, fluorine anion doping at 1 mol/L potassium hydroxide yields an overpotential of 38 mV at a current density of 10 mA/cm². The electrocatalytic efficiency can also be enhanced by adding metal atoms to the nickel sulfide framework.

     

Planting trees to combat global warming

Environmental Chemistry Letters -     

Senna alexandrina extract supplementation reverses hepatic oxidative,inflammatory, and apoptotic effects of cadmium chloride administration in rats

Environmental Science and Pollution Research - Senna alexandrina is traditionally used for its antioxidant and anti-inflammatory properties, but little information is available concerning its...     

Empirics on heterogeneous links among urbanization,the intensity of electric power consumption,water-based emissions,and economic progress in regional China

Environmental Science and Pollution Research - This study investigates the heterogeneous causal linkages between urbanization, the intensity of electric power consumption, water-based pollutant...     

Description of hydrogeologic heterogeneity and evaluation of radionuclide transport at an underground nuclear test

Realistic models of contaminant transport in groundwater demand detailed characterization of the spatial distribution of subsurface hydraulic properties, while at the same time programmatic constraints may limit collection of pertinent hydraulic data. Fortunately, alternate forms of data can be used to improve characterization of spatial variability. We utilize a methodology that augments sparse hydraulic information (hard data) with more widely available hydrogeologic information to generate equiprobable maps of hydrogeologic properties that incorporate patterns of connected permeable zones. Geophysical and lithologic logs are used to identify hydrogeologic categories and to condition stochastic simulations using Sequential Indicator Simulation (SIS). The resulting maps are populated with hydraulic conductivity values using field data and Sequential Gaussian Simulation (SGS). Maps of subsurface hydrogeologic heterogeneity are generated for the purpose of examining groundwater flow and transport processes at the Faultless underground nuclear test, Central Nevada Test Area (CNTA), through large-scale, three-dimensional numerical modeling. The maps provide the basis for simulation of groundwater flow, while transport of radionuclides from the nuclear cavity is modeled using particle tracking methods. Sensitivity analyses focus on model parameters that are most likely to reduce the long travel times observed in the base case. The methods employed in this study have improved our understanding of the spatial distribution of preferential flowpaths at this site and provided the critical foundation on which to build models of groundwater flow and transport. The results emphasize that the impacts of uncertainty in hydraulic and chemical parameters are dependent on the radioactive decay of specific species, with rapid decay magnifying the effects of parameters that change travel time.     

基于测试数据的室内超宽带信道建模研究

基于室内超宽带信道测量研究建立了基于簇的时延抽头模型以及与距离和载频有关的新颖的路径损耗模型,建立了路径损耗同时与距离和频率的依赖关系.同时,研究发现视距和非视距接收信号幅度分别满足莱斯和瑞利分布.该模型对超宽带无线系统仿真和设计有重要的指导意义.