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101.
102.
The correlation of arsenic levels in drinking water with the biological samples of skin disorders 总被引:1,自引:0,他引:1
Tasneem Gul Kazi Muhammad Balal Arain Jameel Ahmed Baig Muhammad Khan Jamali Hassan Imran Afridi Nusrat Jalbani Raja Adil Sarfraz Abdul Qadir Shah Abdul Niaz 《The Science of the total environment》2009,407(3):1019-32
Arsenic (As) poisoning has become a worldwide public health concern. The skin is quite sensitive to As and skin lesions are the most common and earliest nonmalignant effects associated to chronic As exposure. In 2005-2007, a survey was carried out on surface and groundwater arsenic contamination and relationships between As exposure via the drinking water and related adverse health effects (melanosis and keratosis) on villagers resides on the banks of Manchar lake, southern part of Sindh, Pakistan. We screened the population from arsenic-affected villages, 61 to 73% population were identified patients suffering from chronic arsenic toxicity. The effects of As toxicity via drinking water were estimated by biological samples (scalp hair and blood) of adults (males and females), have or have not skin problem (n = 187). The referent samples of both genders were also collected from the areas having low level of As (< 10 μg/L) in drinking water (n = 121). Arsenic concentration in drinking water and biological samples were analyzed using electrothermal atomic absorption spectrometry. The range of arsenic concentrations in lake surface water was 35.2-158 μg/L, which is 3-15 folds higher than World Health Organization [WHO, 2004. Guidelines for drinking-water quality third ed., WHO Geneva Switzerland.]. It was observed that As concentration in the scalp hair and blood samples were above the range of permissible values 0.034-0.319 μg As/g for hair and < 0.5-4.2 μg/L for blood. The linear regressions showed good correlations between arsenic concentrations in water versus hair and blood samples of exposed skin diseased subjects (R2 = 0.852 and 0.718) as compared to non-diseased subjects (R2 = 0.573 and 0.351), respectively. 相似文献
103.
Niaz Md. Farhat Rahman Waqas Ahmed Malik Md. Azizul Baten Md. Shahjahan Kabir Mohammad Chhiddikur Rahman Rokib Ahmed ABM Zahid Hossain Md. Mofazzel Hossain Tuhin Halder Md. Khairul Alam Bhuiyan Mohammad Ashik Iqbal Khan Raihanul Haque Khan Nazmul Ahasan Hans-Peter Piepho 《Journal of the science of food and agriculture》2024,104(4):2303-2313
104.
RB Singh JP Sharma V Rastogi MA Niaz S Ghosh R Beegom ED Janus 《Canadian Metallurgical Quarterly》1997,18(4):588-595
OBJECTIVE: To demonstrate the association of socio-economic status with prevalence of coronary artery disease and coronary risk factors. DESIGN AND SETTING: Cross-sectional survey in two randomly selected villages in the Moradabad district in North India. SUBJECTS AND METHODS: One thousand seven hundred and sixty-seven subjects (894 males and 875 females; 25-64 years of age) were randomly selected from two villages. They were divided into social classes 1 to 4, according to education, occupation, housing conditions, ownership of land, ownership of consumer durables and per capita income. The survey was based on questionnaires administered by dietitians and physicians, physical examination and electrocardiography. RESULTS: Social classes 1 and 2 were mainly high and middle socio-economic groups and 3 and 4 low income groups. The prevalence of coronary artery disease was significantly higher among classes 1 and 2 in both sexes, and there was a higher prevalence of hypercholesterolaemia, hypertension, and sedentary lifestyle. This population also showed a significant association with higher serum cholesterol, body mass index, triglycerides and blood pressures. Logistic regression analysis with adjustment for age showed that social class positively related to coronary disease (odds ratio: men 0.83, women 0.61), hypercholesterolaemia (men 0.85, women 0.87), hypertension (men 0.89, women 0.87), body mass index (men 0.91, women 0.93) and smoking in men (0.68). Smoking and sedentary lifestyle were not associated with social class in women. The association between coronary artery disease and social class abated after adjustment for smoking, sedentary lifestyle, body mass index and blood pressure (odds ratio: men 0.96, women 0.81). CONCLUSION: Subjects in social classes 1 and 2 in rural North India have a higher prevalence of coronary artery disease and of the coronary risk factors hypercholesterolaemia, hypertension, higher body mass index and sedentary lifestyle. The overall prevalence of coronary artery disease was 3.3%. 相似文献
105.
Irrigation water consumption in Saudi Arabia represents about 90% of the national water use, and the limited groundwater resources are the major water supply for irrigation. Improper irrigation water operation accounts for significant water losses in some large irrigation schemes. Consequently, the use of advanced techniques in irrigation operation and scheduling is essential for the reduction of irrigation water demands. A new and original Computerized and Dynamic Irrigation Water Management System (CDIWMS) was developed for automatic and/or manual irrigation operation and scheduling of irrigation schemes containing a large number of fields. The CDIWMS is supported by a comprehensive and dynamic database management system. The system performs several functions, including the dynamic modification of field information and operation conditions such as the delaying or suspension of irrigation, and the setting of fields for cutting or harvesting. The model was tested and implemented successfully in several large irrigation schemes in the Kingdom of Saudi Arabia using full automation and manual operation. The implementation of the CDIWMS has resulted in a saving of more than 25% of the water, energy and costs of operation and maintenance, and in an increase in agricultural production. 相似文献
106.
Muhammad Azhar Khan Mubashar Nadeem Shakeel Abbas Majid Niaz Akhtar Maria Yousuf Lodhi 《Ceramics International》2018,44(18):22255-22261
Dysprosium (Dy) doped Y-type strontium hexa ferrites of the following composition Ni2Sr2DyxFe12-xO22 where (x?=?0.00, 0.05, 0.10, 0.15, 0.20, 0.25) were prepared through co-precipitation process. Phase analysis of the investigated samples was carried out by characterizing through (XRD) X-ray diffraction which confirmed the pure phase of Y-type hexaferrites. Dysprosium ion doping influenced lattice parameters i.e. lattice constants (a, c), crystallite size, (c/a) ratio, cell volume and porosity. The calculated crystallite size was in the range of 88–159?nm. FTIR plots showed that the characteristics bonds of Ni2Sr2DyxFe12-xO22 are appreciably influenced by the incorporation of Dy contents. The results of dielectric parameters revealed that dielectric constant, dielectric loss, tanloss were decreased with an increase in frequency. At 6.0?×?108 Hz, dielectric constant decreased from 5.55 to 3.69 with increasing Dy concentration. Owing to Maxwell-wagner type relaxation, the decrease in dielectric constant was noticed at higher frequency. The smaller dielectric constants and dielectric losses make these materials suitable for their applications in microwave devices fabrication. 相似文献
107.
108.
Bushra Iqbal Andrea Laybourn Anwar ul-Hamid Muhammad Zaheer 《Ceramics International》2021,47(9):12433-12441
In this work, size-controlled synthesis of nickel ferrite nanoparticles was achieved by the calcination of a bimetallic (Fe/Ni) metal-organic framework (MOF). The bimetallic MOF (Fe2Ni-MIL-88B) itself was prepared by a two-step route. The first step involved synthesis of the secondary building unit (SBU) by reacting stoichiometric amounts of Ni and Fe precursors with acetic acid. A ligand substitution reaction (terephthalate replaces acetate) in the SBU leads to the formation of the MOF, which was characterized by PXRD, FTIR, SEM and TEM. Afterwards, the MOF was calcined under air atmosphere to obtain nickel ferrite nanorods. PXRD analysis confirmed the spinel structure of the nickel ferrites while electron microscopic analysis (SEM, TEM) revealed their nanorod-like morphology. By increasing the calcination temperature from 600 to 1000 °C, particle size increased from 16 to 32 nm. Oxidation of benzyl alcohol was used as a model test reaction to probe the applicability of spinel nickel ferrite nanorods for catalysis. Interestingly, the largest nanorods exhibited the highest activity (86% conversion), thus demonstrating the potential of spinel ferrites in catalyzing oxidation reactions. 相似文献
109.
Bushra Shal Adnan Khan Ashraf Ullah Khan Rahim Ullah Gowhar Ali Salman Ul Islam Ihsan ul Haq Hussain Ali Eun-Kyoung Seo Salman Khan 《International journal of molecular sciences》2021,22(12)
The present study aims to determine the neuroprotective effect of Bergenin against spatial memory deficit associated with neurodegeneration. Preliminarily, the protective effect of Bergenin was observed against H2O2-induced oxidative stress in HT-22 and PC-12 cells. Further studies were performed in 5xFAD Tg mouse model by administering Bergenin (1, 30 and 60 mg/kg; orally), whereas Bergenin (60 mg/kg) significantly attenuated the memory deficit observed in the Y-maze and Morris water maze (MWM) test. Fourier transform-infrared (FT-IR) spectroscopy displayed restoration of lipids, proteins and their derivatives compared to the 5xFAD Tg mice group. The differential scanning calorimeter (DSC) suggested an absence of amyloid beta (Aβ) aggregation in Bergenin-treated mice. The immunohistochemistry (IHC) analysis suggested the neuroprotective effect of Bergenin by increasing Reelin signaling (Reelin/Dab-1) and attenuated Aβ (1–42) aggregation in hippocampal regions of mouse brains. Furthermore, IHC and western blot results suggested antioxidant (Keap-1/Nrf-2/HO-1), anti-inflammatory (TLR-4/NF-kB) and anti-apoptotic (Bcl-2/Bax/Caspase-3) effect of Bergenin. Moreover, a decrease in Annexin V/PI-stained hippocampal cells suggested its effect against neurodegeneration. The histopathological changes were reversed significantly by Bergenin. In addition, a remarkable increase in antioxidant level with suppression of pro-inflammatory cytokines, oxidative stress and nitric oxide production were observed in specific regions of the mouse brains. 相似文献
110.
Muhammad Badar Hayat Danish Ali Keitumetse Cathrine Monyake Lana Alagha Niaz Ahmed 《国际能源研究杂志》2019,43(3):1049-1067
Sun is an inexhaustible source of energy capable of fulfilling all the energy needs of humankind. The energy from the sun can be converted into electricity or used directly. Electricity can be generated from solar energy either directly using photovoltaic (PV) cells or indirectly using concentrated solar power (CSP) technology. Progress has been made to raise the efficiency of the PV solar cells that can now reach up to approximately 34.1% in multi‐junction PV cells. Electricity generation from concentrated solar technologies has a promising future as well, especially the CSP, because of its high capacity, efficiency, and energy storage capability. Solar energy also has direct application in agriculture primarily for water treatment and irrigation. Solar energy is being used to power the vehicles and for domestic purposes such as space heating and cooking. The most exciting possibility for solar energy is satellite power station that will be transmitting electrical energy from the solar panels in space to Earth via microwave beams. Solar energy has a bright future because of the technological advancement in this field and its environment‐friendly nature. The biggest challenge however facing the solar energy future is its unavailability all‐round the year, coupled with its high capital cost and scarcity of the materials for PV cells. These challenges can be met by developing an efficient energy storage system and developing cheap, efficient, and abundant PV solar cells. This article discusses the solar energy system as a whole and provides a comprehensive review on the direct and the indirect ways to produce electricity from solar energy and the direct uses of solar energy. The state‐of‐the‐art procedures being employed for PV characterization and performance rating have been summarized . Moreover, the technical, economic, environmental, and storage‐related challenges are discussed with possible solutions. Furthermore, a comprehensive list of future potential research directions in the field of direct and indirect electricity generation from solar energy is proposed. 相似文献