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601.
The objective of this work was to assess the current concentrations of total suspended particles (TSP) and trace metals in the urban atmosphere of Islamabad, Pakistan, where local industries, transportation, and urbanization are adversely affecting air quality. Air sampling was done using a high-volume sampler and the metals were estimated in TSP by Flame Atomic Absorption Spectrophotometry. An annual mean TSP of 151.9 μ g/m3 was determined for the period May 2003–April 2004, which exceeded the World Health Organization's (WHO's) primary and secondary standards of air quality. The TSP metal concentrations were compared with those reported in literature for other regions of the world and with air quality standards laid down by regulatory agencies. The levels of Na, Fe, Zn, Pb, Mn, Cr, Co, and Cd for the present study were higher than most of the levels reported for other typical industrial and urban areas of the world. The airborne Ni concentrations were higher than the WHO and the U.S. Environmental Protection Agency's standards. Cluster and Principal Component Analyses of the data were used to identify the sources of the metals and establish their mutual correlations in the local atmosphere. 相似文献
602.
603.
Ghulam Shabir Solangi Altaf Ali Siyal Muhammad Munir Babar Pirah Siyal 《人类与生态风险评估》2020,26(6):1529-1549
AbstractUnder changing climate scenario, groundwater aquifers in the coastal areas of Pakistan are under serious threat. Looking at the gravity of the problem, and concerns of the civil society, this study was conducted to evaluate and map the quality of groundwater in the Sujawal district, a coastal area of Pakistan based on the physicochemical analysis of 94 samples using two standard numerical models and geospatial techniques. The WQI model revealed that 2.13%, 6.38%, 55.32%, 22.34%, and 13.83% of water samples were excellent, good, poor, very poor, and unsuitable for drinking purposes. Also, the SPI model identified that 32%, 13.83%, 20.12%, 18.1%, and 15.95% of samples were slightly polluted, moderately polluted, highly polluted, suitable, and unsuitable. Though the model's input is different, the proportionate of ranking revealed a significant correlation (R2=0.78) between the outcomes of both models. Overall, the study revealed that groundwater in most of the areas does not meet WHO guidelines. The prevalence of water-related diseases in the area suggests that groundwater is contaminated and using that water is of high risk for human health. The study highlights the significance of using numerical models and geospatial techniques for water quality evaluation in the coastal areas of the world. 相似文献
604.
Ghulam Md Ashraf Sabika Rizvi Shoa Naqvi Nida Suhail Nayeem Bilal Shirin Hasan Mohammad Tabish Naheed Banu 《Amino acids》2010,39(5):1321-1332
A soluble β-galactoside-binding lectin was purified by gel filtration chromatography from Bubalus bubalis heart. Its metal-independent nature, molecular weight of 14.5 kDa, preferential affinity for β-d-lactose, and 87–92% identity with carbohydrate recognition domain of previously reported galectin-1 confirmed its inclusion
in galectin-1 subfamily. Stokes radii determination using gel filtration under reducing and non-reducing conditions revealed
its homo-dimeric nature, further confirming its Gal-1 nomenclature. The purified lectin was found to be the most stable mammalian
heart galectin purified till date, suggesting its preferential use in various recognition studies. Treatment of the purified
lectin with oxidizing agent, thiol blocking reagents, denaturants, and detergents resulted in significant changes in UV–VIS,
fluorescence, CD and FTIR spectra, which strongly emphasized the important aspect of regular secondary structure of galectins
for the maintenance of their active conformation. Reduction of the activity of the purified lectin after oxidation by H2O2, with remarkable fluorescence quenching, may suggest potential role for galectin-1 in free radical-induced, oxidative stress-mediated
cardiovascular disorders. The predictions of bioinformatics studies were found to be in accordance with the results obtained
in wet lab. 相似文献
605.
A. A. Khan S. Ahmad I. Hussain S. Munir 《International biodeterioration & biodegradation》2000,45(3-4)
In Pakistan, Hystrix indica is abundant and distributed all over the country. It has been identified as a serious pest of traditional as well as non-traditional crops, fruit orchards, vegetables, flowering plants and grasses of forage importance in rangelands. The most important porcupine damage, however, occurs in forestry and reforestation areas. Damage estimates of 52.5% to Melia azedarach, 24.3% to Morus alba and 1% to Dalbergia sissoo in different irrigated forest plantations of Punjab has been described. Severe stocking damage of 60% to Pinus roxburghii and 42% to Robinia pseudoacacia was recorded in different areas of Tarbela Watershed Management Project. Crops of economic importance such as maize, groundnut and potatoes are severely damaged in irrigated plains and mountain regions. Among the vegetables, okra, pumpkin, bitter gourd, and onions are badly damaged. In rangelands different species of grasses such as Pennisetum sp., Cenchrus ciliaris and Cymbopogan jawarancusa are uprooted which severely affects sustainable grazing. Dirt raised embankments of link and irrigational canals have become weakened because of the most favourable denning sites for the porcupines. Damage to plastic tubing is common where drip irrigation is practised. 相似文献
606.
Mohamad Hadi Saeed Modaghegh Shirin Saberianpour Sakineh Amoueian Jamal Jalili Shahri Hamidreza Rahimi 《Biochemistry and Biophysics Reports》2021
Introduction& Objectives: Redox signaling is a critical regulator in the process of wound healing. This signaling pathway can be effective in the development or healing of diabetic ulcers through the ECM.In this study, the structure of extracellular matrix investigated in relation to redox signaling in the tissue of patients with diabetic ulcers that lead to organ amputation.Materials and methodsThe case-control design on diabetic patients ulcers as case group and non-diabetic limb ischemia as control were used.Hematoxylin-eosin, trichrome, and elastin staining methods were used for pathological evaluations of ECM. MDA, total thiol, and SOD levels were measured using ELISA kits to assess the oxidative stress level. Also, NO level was measured by using ELISA kits in both groups. Expression levels of genes MMP2, MMP9, and HIF were detected using real-time PCR with SYBR-green assay.ResultsThe pathological results showed an increase in the thickness of collagen and elastin fibers. Lipids atrophy was visible in the tissue isolated from the diabetic wound group. The amount of MAD to evaluate the level of lipid oxidation in patients with diabetic Ulcer was significantly higher than the control group(p < 0.01). Thiol level was significantly lower in the diabetic ulcer group than in the control group(p < 0.0001). The expression of metalloproteinases 2 and 9 genes in the tissues isolated from diabetic ulcers was lower than the control group(p < 0.0001). While the expression of the HIF gene in this group was higher than the control group(p < 0.0001).ConclutionIn the diabetic wound, the HIF secretion due to hypoxic conditions is beneficial for matrix deposition and prevents protease activity, but if the hypoxia persists, it can lead to ECM deposition subsequently increases the tissue pressure, increases of the collagen I-to-collagen III ratio in collagen accumulation that due to more hypoxia , lipidsAtrophy and eventually amputation. 相似文献