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91.
Iodine deficiency is a global public health issue because iodine plays a major role in the thyroid hormone synthesis and is essential for normal neurological development. This review summarizes the publications on iodine status in the WHO Eastern Mediterranean Region (EMR) countries. All related studies available in main national and international databases were systematically searched using some specific keywords to find article published between 1909 and 2015. The prevention of iodine deficiency disorders (IDDs) in the WHO EMR countries is currently under control without significant side effects. Mild to severe IDDs exist in some countries of the Middle East, due to lack of effective iodine supplementation program, but the Islamic Republic of Iran, Jordan, Bahrain and Tunisia have achieved the goal of universal salt iodization. Overall, despite enormous efforts to control IDDs, still IDD remains a serious public health problem in some countries of the region, requiring urgent control and prevention measures.  相似文献   
92.
Soil is damaged by several threats and, among them, chemical contamination by pesticides and compaction. However, the effect of compaction on the fate of pesticides in soil, and the impact of pesticides on soil biological functioning are unknown. Therefore, we studied the effect of soil compaction on the degradation of the herbicide isoproturon, and the impact of this herbicide on an enzyme activity (β-glucosidase) involved in the C soil cycle. Undisturbed soil samples were prepared at different bulk densities, treated with isoproturon then incubated at 18°C in darkness for 63 days. The results showed that soil compaction did not modify significantly the degradation of isoproturon, neither the formation rates nor the nature of its metabolites. Moreover, compaction did not modify the impact of isoproturon on β-glucosidase activity. To our knowledge, these are the first results concerning the interactions between soil compaction and the degradation and impact of a pesticide.  相似文献   
93.
Landscape planning and restoration in mine closure areas is not only an inevitable choice to sustain mining areas but also an important path to maximize landscape resources and to improve ecological function in mine closure areas. The analysis of the present mine development shows that many mines are unavoidably facing closures in China. This paper analyzes the periodic impact of mining activities on landscapes and then proposes planning concepts and principles. According to the landscape characteristics in mine closure areas, this paper classifies available landscape resources in mine closure areas into the landscape for restoration, for limited restoration and for protection, and then summarizes directions for their uses. This paper establishes the framework of spatial control planning and design of landscape elements from “macro control, medium allocation and micro optimization” for the purpose of managing and using this kind of special landscape resources. Finally, this paper applies the theories and methods to a case study in Wu’an from two aspects: the construction of a sustainable land-use pattern on a large scale and the optimized allocation of typical mine landscape resources on a small scale.  相似文献   
94.
Adaptation is a key factor for reducing the future vulnerability of climate change impacts on crop production. The objectives of this study were to simulate the climate change effects on growth and grain yield of maize (Zea mays L.) and to evaluate the possibilities of employing various cultivar of maize in three classes (long, medium and short maturity) as an adaptation option for mitigating the climate change impacts on maize production in Khorasan Razavi province of Iran. For this purpose, we employed two types of General Circulation Models (GCMs) and three scenarios (A1B, A2 and B1). Daily climatic parameters as one stochastic growing season for each projection period were generated by Long Ashton Research Station-Weather Generator (LARS?WG). Also, crop growth under projected climate conditions was simulated based on the Cropping System Model (CSM)-CERES-Maize. LARS-WG had appropriate prediction for climatic parameters. The predicted results showed that the day to anthesis (DTA) and anthesis period (AP) of various cultivars of maize were shortened in response to climate change impacts in all scenarios and GCMs models; ranging between 0.5 % to 17.5 % for DTA and 5 % to 33 % for AP. The simulated grain yields of different cultivars was gradually decreased across all the scenarios by 6.4 % to 42.15 % during the future 100 years compared to the present climate conditions. The short and medium season cultivars were faced with the lowest and highest reduction of the traits, respectively. It means that for the short maturing cultivars, the impacts of high temperature stress could be much less compared with medium and long maturity cultivars. Based on our findings, it can be concluded that cultivation of early maturing cultivars of maize can be considered as the effective approach to mitigate the adverse effects of climate.  相似文献   
95.
Environmental Science and Pollution Research - Germanium as a strategic metalloid is widely used in high-tech devices. The most crucial germanium resources are rare and limited to zinc minerals,...  相似文献   
96.
Environmental Science and Pollution Research - Environmental degradation is one of the main drivers of climate change. One of the most broadly accepted tools to minimize environmental degradation...  相似文献   
97.
Environmental Science and Pollution Research - The United Nations’s Sustainable Development Goals (SDGs) is international cooperation that aims to climate change mitigation, and encourage the...  相似文献   
98.

The adsorption and photo-Fenton degradation of tetracycline (TC) over Fe-saturated nanoporous montmorillonite was analyzed. The synthesized samples were characterized using XRD, FTIR, SEM, and XRF analysis, and the adsorption and desorption of TC onto these samples, as well as the antimicrobial activity of TC during these processes, were analyzed at different pH. Initially, a set of adsorption/desorption experiments was conducted, and surprisingly, up to 50% of TC adsorbed was released from Mt structure. Moreover, the desorbed TC had strong antibacterial activity. Then, an acid treatment (for the creation of nanoporous layers) and Fe saturation of the montmorillonite were applied to improve its adsorption and photocatalytic degradation properties over TC. Surprisingly, the desorption of TC from modified montmorillonite was still high up to 40% of adsorbed TC. However, simultaneous adsorption and photodegradation of TC were detected and almost no antimicrobial activity was detected after 180 min of visible light irradiation, which could be due to the photo-Fenton degradation of TC on the modified montmorillonite surface. In the porous structures of modified montmorillonite high, ˙OH radicals were created in the photo-Fenton reaction and were measured using the Coumarin technique. The ˙OH radicals help the degradation of TC as proposed in an oxidation process. Surprisingly, more than 90% of antimicrobial activity of the TC decreased under visible light (after 180 min) when desorbed from nanoporous Fe-saturated montmorillonite compared to natural montmorillonite. To the best of our knowledge, this is the first time that such a high TC desorption rate from an adsorbent with the least residual antimicrobial activity is reported which makes nanoporous Fe-saturated montmorillonite a perfect separation substance of TC from the environment.

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99.
In this study, a traditional assay was modified to evaluate the effect of Hg, Cd, and Zn on the bacterial community of a sequencing batch reactor and activated sludge plants and heavy metal-resistant bacterial species were determined. After the isolation of metal-resistant bacteria, their 16S rRNA gene fragments were sequenced. The BLAST program was used to compare the resulting 16S rRNA sequences with those in GenBank database to identify the isolated bacterial species. Hg was found to be the most toxic metal for both bacterial communities investigated. Sequence batch reactor bacteria were comparatively more resistant to Hg, Cd, and Zn than those from activated sludge. The resistant strains were close to the members of genus Pseudomonas, Kocuria, Stenotrophomonas, Enterococcus, and Staphylococcus. The modified dehydrogenase enzyme assay seems to be simple, robust, and competent for evaluation of the impact of metals on bacterial activity. Sequencing batch reactor systems should be preferred over activated sludge when wastewaters containing hazardous metals are to be treated.  相似文献   
100.
Metallic pollution caused by elements Zn, Cu, Fe, Pb, Ni, Cd, and Hg in water and sediments of Aras River within a specific area in Ardabil province of Iran is considered. Water and sediment samples were collected seasonally and once respectively from the five selected stations. Regarding WHO published permissible values, only Ni concentration in spring and summer water samples has exceeded the acceptable limit up to four times greater than the limit. The concentration of metals Ni, Pb, and Fe in river water shows a direct relationship with river water discharge and the amount of precipitation. Enhanced soil erosion, bed load dissolution, and runoffs may play a key role in remarkable augmentation of metallic ions concentration. Furthermore, excessive use of pesticides which contain a variety of metallic ions (mainly Cu) in spring and summer may also result in an increase in the metals’ concentration. The potential risk of Ni exposure to the water environment of the study area is assigned to juice, dairy products, edible oil, and sugar cane factories as well as soybean crop lands which are located within the sub-basin of Aras River in the study area. Regarding the sediment samples, the bioavailable metal concentrations indicate an ascending order from the first station towards the last one. In comparison with earth crust, sedimental and igneous rocks the reported metallic concentration values, except for Cd, lie within the low-risk status. Regarding Cd, the reported values in some stations (S2, S4, and S5) are up to ten times greater than that of shale which may be considered as a remarkable risk potential. The industrial and municipal wastewater generated by Parsabad moqan industrial complex and residential areas, in addition to the discharges of animal husbandry centers, may be addressed as the key factors in the sharp increase of metallic pollution potential in stations 4 and 5.  相似文献   
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