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71.
Various natural hazards such as landslides, avalanches, floods and debris flows can result in enormous property damages and human casualties in Eastern Black Sea region of Turkey. Mountainous topographic character and high frequency of heavy rain are the main factors for landslide occurrence in Ardesen, Rize. For this reason, the main target of the present study is to evaluate the landslide hazards using a sequence of historical aerial photographs in Ardesen (Rize), Turkey, by Photogrammetry and Geographical Information System (GIS). Landslide locations in the study area were identified by interpretation of aerial photographs dated in 1973 and 2002, and by field surveys. In the study, the selected factors conditioning landslides are lithology, slope gradient, slope aspect, vegetation cover, land class, climate, rainfall and proximity to roads. These factors were considered as effective on the occurrence of landslides. The areas under landslide threat were analyzed and mapped considering the landslide conditioning factors. Some of the conditioning factors were investigated and estimated by employing visual interpretation of aerial photos and topographic data. The results showed that the slope, lithology, terrain roughness, proximity to roads, and the cover type played important roles on landslide occurrence. The results also showed that degree of landslides was affected by the number of houses constructed in the region. As a consequence, the method employed in the study provides important benefits for landslide hazard mitigation efforts, because a combination of both photogrammetric techniques and GIS is presented.  相似文献   
72.
Total-recoverable metals (Al, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in sediments from Minho estuary salt marsh were determined to evaluate possible increase in anthropogenic contamination by metals and to evaluate the possibility of this area to be considered a pristine area in terms of metals, which can be used as a reference site for other metal-contaminated national and international estuaries/salt marshes. This study revealed that the spatial distribution of metals in the salt marsh sediments was not homogeneous and that two sampling sites (sites 5 and 7) had indications of anthropogenic contamination. However, metal levels in these salt marsh sediments were lower than those observed in the wetlands of the main Portuguese estuaries. Comparison with Portuguese and international reference values used in the evaluation of the ecological quality of sediments, indicated that the sediments can be classified as “clean sediment” and that metal levels were lower or similar (only for Cu and Ni) to the values of ERL, which are the values that define the concentrations ranges that are rarely associated to adverse biologic effects in organisms. In addition, metal levels in the sediments were in chemical forms that were not easily available to organisms, indicating that these sediments probably will not have negative influences in the organisms living in the salt marsh, although no life-form ecological safety tests have been carried out. Therefore, the Minho estuary salt marsh area can probably be considered a pristine area in terms of metals and can be used as a reference for other metal-contaminated estuaries/salt marshes.  相似文献   
73.
An intensive sampling campaign has been carried out in a municipal wastewater treatment plant (WWTP) to assess the dynamics of the influent pharmaceutical active compounds (PhAC) and musks. The mass loadings of these compounds in wastewater influents displayed contrasting diurnal variations depending on the compound. The musks and some groups of PhACs tended to follow a similar diurnal trend as compared to macropollutants, while the majority of PhACs followed either the opposite trend or no repeatable trend. The total musk loading to the WWTP was 0.74 ± 0.25 g d−1, whereas the total PhAC mass loading was 84.7 ± 63.8 g d−1. Unlike the PhACs, the musks displayed a high repeatability from one sampling day to the next. The range of PhAC loadings in the influent to WWTPs can vary several orders of magnitude from one day or week to the next, representing a challenge in obtaining data for steady-state modelling purposes.  相似文献   
74.
75.
The general objective of this in vitro study was to examine the effect of bee pollen on the release of insulin-like growth factor I (IGF-I) and steroid hormone progesterone, and expression of markers of proliferation (PCNA) and apoptosis (caspase-3) in porcine ovarian granulosa cells. Concentrations of IGF-I and progesterone were determined by RIA method and expression of PCNA and caspase-3 by immunocytochemistry. Bee pollen addition at the dose of 10 ng/mL significantly (P<0.05) inhibited IGF-I release by porcine ovarian granulosa cells. This growth factor was not influenced by 100 and 1000 ng/mL doses of bee pollen. Progesterone release by cells was not influenced by bee pollen addition at the doses of 10, 100 and 1000 ng/mL as used in our study. Similarly expression of PCNA and caspase-3 was not affected by bee pollen addition. The present study shows dose-dependent regulation of IGF-I by experimental bee pollen addition in vitro. Progesterone release, expression of PCNA and caspase-3 in porcine ovarian granulosa cells was not induced by pollen. Our results contribute to new insights regarding the possible effect of bee pollen on IGF-I release, which is important for regulation of porcine ovarian functions.  相似文献   
76.
Environmental Science and Pollution Research - Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using...  相似文献   
77.
In order to avoid that contaminated frog farms animals escaping in the environment and become potential vector of emergent diseases, studies with disinfection protocol are strictly necessary. The formaldehyde is one of the compounds tested in fungal disinfection protocols and also used in aquaculture. This study aimed to determine the median lethal concentration (LC50–96h) of formaldehyde in bullfrog tadpoles and to evaluate the possible genotoxic effects in acute exposition. Accordingly, the animals were exposed to formaldehyde in the concentrations of 6, 9, 12, 15, and 18 mg L?1, and after 96 h blood samples were drawn for the micronucleus (MN) test. The LC50–96h was 10.53 mg L?1, and the MN frequency increased in proportion to the formaldehyde concentrations, with an estimated frequency in the negative control being 1.35 MN/individual. We concluded that formaldehyde is genotoxic to tadpoles of bullfrogs in the tested concentrations, and the choice of this chemical should be contemplated before its use in animals in captivity.  相似文献   
78.
To gain a better understanding of the physiology of the herbicide aminocyclopyrachlor in young plants of trumpet flower, the uptake and translocation were evaluated after the application of herbicide. This was determined by treating individual leaves with formulated herbicides plus 14C-aminocyclopyrachlor after the application of the formulated herbicide. This experiment used a randomized experimental design with three replications. In addition, field studies were conducted to assess the effectiveness of foliar applications of aminocyclopyrachlor in association with metsulfuton-methyl. The plant absorbed 20% of the herbicide applied. The translocation percentage did not surpass 5% of the total amount applied. Only 1% of the herbicide applied was translocated to the roots. Rate of 40 + 13 g a.i. 100 L?1 of aminocyclopyrachlor+metsulfuron-methyl was effective to control T. stans.  相似文献   
79.
The main objective of this study is to generate a knowledge base which is composed of user-defined variables and included raster imagery, vector coverage, spatial models, external programs, and simple scalars and to develop an expert classification using Landsat 7 (ETM+) imagery for land cover classification in a part of Trabzon city. Expert systems allow for the integration of remote-sensed data with other sources of geo-referenced information such as land use data, spatial texture, and digital elevation model to obtain greater classification accuracy. Logical decision rules are used with the various datasets to assign class values for each pixel. Expert system is very suitable for the work of image interpretation as a powerful means of information integration. Landsat ETM data acquired in the year 2000 were initially classified into seven classes for land cover using a maximum likelihood decision rule. An expert system was constructed to perform post-classification sorting of the initial land cover classification using additional spatial datasets such as land use data. The overall accuracy of expert classification was 95.80%. Individual class accuracy ranged from 75% to 100% for each class.  相似文献   
80.
The present work studies the visible-light-promoted photodegradation of the colorless fungicide carbendazim (methyl 2-benzimidazolecarbamate) and several 2-substituted benzimidazoles (SBZ's), in water or water-methanol solution, in the presence of air and, as a photosensitizer, the synthetic xanthene dye Rose Bengal (RB) or the natural pigment riboflavin (Rf). The results indicate that the degradation of each particular SBZ depends on its chemical structure and on the sensitizer employed. In the presence of RB, the degradation always operates via a singlet molecular oxygen (O(2)((1)Delta(g)))-mediated mechanism, through a highly efficient process, as deduced from the comparison of the rate constants for physical and chemical quenching of O(2)((1)Delta(g)). In the presence of Rf, the visible-light irradiation of any of the studied SBZ's produces a series of competitive processes that depend on the relative concentrations of Rf and SBZ. These processes include the quenching of excited singlet and triplet Rf states by the SBZ and the generation of both O(2)((1)Delta(g)) and superoxide radical anion (O(2)(-)), the latter generated by electron transfer from excited Rf species to the dissolved oxygen. The overall result is the photodegradation of the SBZ and the photoprotection of the sensitizer.  相似文献   
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