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81.
In this study, the levels of some heavy metals (Al, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb and Zn) in muscle, gill, and liver of Carassius carassius and in the water samples from Eber Lake (Afyonkarahisar, Turkey) have been investigated. Additionally, one of the lipid peroxidation markers, malondialdehide (MDA) and glutathion (GSH) levels were investigated. All the metal analysis was performed by using ICP-AES. According to results obtained, it was observed that heavy metals were accummulated in liver in the highest degree and lowest one in the muscle tissues. MDA and GSH levels varied in the seasons but their winter levels were found to be statistically meaningful when compared with other seasons. The obtained data of metals from the study were compared with the acceptable levels of Turkish governmental regulation and they were found not to be harmful for human health. On the other hand, it was suggested that oxidative stress markers should be checked regularly in order to get important data for continuous life of aquatic organisms.  相似文献   
82.
Anthropogenic (aquaculture) changes in environment nutrient concentrations may affect phytoplankton (biomass and taxa composition) in marine coastal waters off the Chilean Patagonia. The effects of adding nitrate (NO3 ?) to natural phytoplankton assemblages were evaluated considering biomass, cell abundance, and taxonomic composition. Microcosm experiments were performed in the spring, summer, and winter in the Comau Fjord located in Subantarctic Patagonia. At the end of the experiments, NO3 ? decreased rapidly and was undetectable in treatments, indicating a strong NO3 ? deficiency associated with an exponential increase in Chl-a concentrations, particulate organic nitrogen, and carbon in these treatments. Moreover, given the depleted nitrate concentrations of the spring and summer experiments, the micro-phytoplankton taxa structure shifted from mixed diatom and dinoflagellate assemblages (Ceratium spp., Dinophysis spp., Coscinodiscus sp., Rhizosolenia pungens) to assemblages dominated by blooms of the classic chain-forming diatoms found in temperate and cold waters such as Chaetoceros spp., Skeletonema spp., and Thalassiosira spp. Thus, nitrogen sources (i.e., nitrate, ammonia) may influence phytoplankton abundance and biomass accumulation dynamics in the northern section of Patagonia. It also emphasizes the importance of diatom taxa in regards to the short-term response of phytoplankton to changing environmental nutrient conditions due to natural (decreasing freshwater stream flow) and anthropogenic (aquaculture) events. This situation may be one of the future scenarios in the Patagonian fjords, thus stressing the needs for active environmental monitoring and impact assessment.  相似文献   
83.
An inhibitory effect of a traditional Japanese fermented food, natto, was found against plant pathogens such as Rhizoctonia solani and Fusarium oxysporum, and the bacteria which showed inhibition were isolated from the natto. Among isolated bacteria, BC-1 and GAc exhibited a strong antagonistic effect in vitro against plant pathogens on an agar medium. The supernatant of bacterial culture also showed strong activity against R. solani, which meant the antimicrobial substances were produced and secreted into the medium. Both of the bacteria were estimated as Bacillus amyloliquefaciens from a partial sequence of the 16s rRNA gene. High performance liquid chromatography analysis clearly showed the production of the lipopeptide antibiotic iturin A by BC-1 and GAc.  相似文献   
84.
Joubert syndrome is a rare, autosomal recessive condition, first described by Joubert in 1969. We present a case of Joubert syndrome from a consanguineous family in which, apart from the cerebellar vermis agenesis, ventriculomegaly, bilateral postaxial polydactyly of hands and right foot and micropenis, episodes of fetal breathing pattern with an increased respiratory rate were also demonstrated by prenatal ultrasound scan. At birth the infant showed an odd face and bilateral fleshy nodules of the tongue. He had an abnormal breathing pattern of alternating tachypnea and apnea. Cranial MRI showed molar tooth sign, hydrocephalus and Dandy–Walker malformation. He had nystagmus, and electroretinography showed retinal dystrophy. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
85.
Assessment of big floods in the Eastern Black Sea Basin of Turkey   总被引:1,自引:0,他引:1  
In this study, general knowledge and some details of the floods in Eastern Black Sea Basin of Turkey are presented. Brief hydro-meteorological analysis of selected nine floods and detailed analysis of the greatest flood are given. In the studied area, 51 big floods have taken place between 1955–2005 years, causing 258 deaths and nearly US $500,000,000 of damage. Most of the floods have occurred in June, July and August. It is concluded that especially for the rainstorms that have caused significantly damages, the return periods of the rainfall heights and resultant flood discharges have gone up to 250 and 500 years, respectively. A general agreement is observed between the return periods of rains and resultant floods. It is concluded that there has been no significant climate change to cause increases in flood harms. The most important human factors to increase the damage are determined as wrong and illegal land use, deforestation and wrong urbanization and settlement, psychological and technical factors. Some structural and non-structural measures to mitigate flood damages are also included in the paper. Structural measures include dykes and flood levees. Main non-structural measures include flood warning system, modification of land use, watershed management and improvement, flood insurance, organization of flood management studies, coordination between related institutions and education of the people and informing of the stakeholders.  相似文献   
86.
87.
In this study, EPS produced by five Bacillus spp. strains was determined. The only one strain (B. sphaericus 7055) was selected due to its high EPS production and it was investigated by growing this strain in LB broth medium containing various carbon sources. The highest EPS production of this strain was found in medium containing fructose. However, the effect of different concentrations of fructose and molasses on EPS production by the strain was studied. The maximum EPS yield of the strain 7055 was recorded with 2.5% (w/v) fructose, also the highest EPS production was found in 2.5% (w/v) molasses. The strain 7055 was found to contain (98.6%) galactose and (1.4%) glucuronic acid in control medium whereas the composition of the strain 7055 (2.5% (w/v) fructose) was found to be (99.9%) neutral sugar and (0.1%) Glucuronic acid while the strain 7055 (2.5% (w/v) molasses) was found to contain (65.9%), neutral sugars and (34.1%) glucuronic acid.  相似文献   
88.
A nonlethal form of multiple pterygium syndrome (MPS) was diagnosed prenatally at 16 weeks of gestation with associated Klinefelter syndrome in the same fetus. The ultrasound findings were cystic hygroma, hypertelorism, micrognathia, low-set ears, flexion contractures of upper and lower extremities and rocker-bottom foot. Genetic amniocentesis revealed a 47,XXY karyotype. After genetic counseling, the parents decided to have a therapeutic abortion. We presented this case for the purpose of further describing the early ultrasound findings and clinical features of multiple pterygium syndromes. Also, what makes our patient unique is the coincidental presence of Klinefelter syndrome with MPS. To our knowledge, this is the first case in the literature in which a 47,XXY karyotype has been found in a fetus with multiple pterygium syndrome. The importance of delineating the exact subtype of MPS and making a precise differential diagnosis becomes critical during the process of evaluation of patients with MPS. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
89.
Remote sensing technology offers an opportunity to significantly increase the amount of site-specific information about field characteristics such as pest populations. Coupled with variable rate application technologies, this added information has the potential to provide environmental benefits through reduced pesticide applications. However, producers face a complicated adoption decision because output prices and crop yields are uncertain. A model is developed to examine the potential value of remote sensing information to pesticide applications in an option-value framework under uncertainty. Simulations suggest that remote sensing information could decrease pesticide use, but uncertainty and irreversibility are likely to limit technological adoption by farmers. Potential cost-share subsidies are discussed.  相似文献   
90.
To reduce nonpoint source pollution from nutrient, chemical, and sediment runoff, a number of environmental policy standards have been proposed. Such standards could be used to reduce nonpoint source pollution from nutrient, chemical, and sediment runoff to impaired water bodies. State governments can use voluntary approaches to meet nonpoint source pollution reduction goals. However, the practices that lower net returns will not be voluntarily adopted by farmers. Crop rotations and tillage practices may help producers to comply with the environmental standards while minimizing losses in farm profits. This study compares runoff from crop rotation practices and conventional continuous row cropping systems in Mississippi. The results are compared for different tillage systems in order to examine robustness of results. Nutrient runoff and sediment runoff are simulated using the Erosion Productivity Impact Calculator (EPIC). Sensitivity analysis of the sediment and nitrate reductions at 15 percent, 25 percent, and 35 percent are conducted. Under these scenarios, net returns are optimized under environmental constraints, and the marginal cost of sediment reduction ranges from US$1.61 to US$9.63 per ton depending on soil conditions, while the corresponding nitrate and phosphorus reductions costs range from US$1.21 to US$7.08 per kg and from US$0.09 to US$31.91, respectively. The empirical results from this study indicate that a nitrate reduction policy is relatively less costly than a sediment reduction policy. The results also demonstrate the importance of geophysical conditions and policy costs, which vary across regions.  相似文献   
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