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1.
Two new species of the genus Quadroppia Jacot, 1939, Quadroppia (Coronoquadroppia) squarrosa sp. n. and Quadroppia (Quadroppia) foveolata sp. n. are described and illustrated from Turkey. They were collected from soil and litter under pear trees (Pyrus communis) and moss on rock, respectively.  相似文献   
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The complex intermixing morphology is critical for the performance of the nanostructured polymer:fullerene bulk heterojunction (BHJ) solar cells. Here, time resolved in situ grazing incidence X‐ray diffraction and grazing incidence small angle X‐ray scattering are used to track the structure formation of BHJ thin films formed from the donor polymer poly(2,5‐bis(3‐hexadecylthiophen‐2‐yl)thieno[3,2‐b]thiophene) with different fullerene derivative acceptors. The formation of stable bimolecular crystals through the intercalation of fullerene molecules between the side chains of polymer crystallites is investigated. Such systems exhibit more efficient exciton dissociation but lower photo‐conductance and faster decay of charges. On the basis of the experimental observations, intercalation obviously takes place before or with the formation of the crystalline polymer domains. It results in more stable structures whose volume remains constant upon further drying. Three distinct periods of drying are observed and the formation of unidimensional fullerene channels along the π‐stacking direction of polymer crystallites is confirmed.  相似文献   
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This paper describes the plant communities of two oligotrophic karstic rivers with a slight anthropogenic influence — the Trebi?at and the Li?tica — in South Bosnia and Herzegovina, their sinecology, and the relationship between vegetation and plant species and environmental parameters. According to 87 relevés, a total of 26 plant associations, using Braun-Blanquet methods, were found in the rivers and nearby surveyed area. Only nine associations were common to both rivers. Eight associations were recorded for the territory of Bosnia and Herzegovina for the first time. Associations from both rivers differed according to following parameters measured at the sampling site: water temperature, distance from the mouth (river kilometers), river width, water depth, flow, pH and slope. There were no differences in nutrient concentrations among the associations. According to Canonical Correspondence Analysis (CCA), three environmental variables out of the 11 initially considered were retained as being related to plant distribution. The first two axes explained 56.8% and 35.2% of variance of species-environment relationship in the Trebi?at and Li?tica rivers, respectively. Water depth in the Trebi?at River, and pH and river kilometers in the Li?tica River were found to be the most influential, while nutrients and other physico-chemical parameters were not significant in either river. Water depth vector was identified as an underlying environmental factor determining distribution of Potamogeton lucens and Myriophyllum verticillatum (Potamion), and Nymphaea alba (Nymphaeion albae). According to in situ measurements of light intensity, the highest coefficients of light attenuation, radiance and reflection were found at a station with dense populations of Potamogeton lucens and Nuphar luteum (Potametum lucentis). The vegetation and floristic value of the rivers is discussed as a basis for biodiversity conservation programmes and evaluating the state of these ecosystems in the future.  相似文献   
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Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential.  相似文献   
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It is known that certain trace elements can affect various heart diseases. In this study, we aimed to evaluate the changes in concentrations of certain serum trace elements in patients with chronic rheumatic heart disease (RHD). Serum analysis of selenium (Se), zinc (Zn), and copper (Cu) trace elements was assayed by atomic absorption spectrophotometry. RHD patients had significantly lower serum concentrations of Se and Zn than control subjects (p < 0.05 and p < 0.001, respectively). However, the serum Cu concentration was significantly higher in RHD patients than in controls (1.93 +/- 0.59 microg/L vs 1.06 +/- 0.29 microg/L; p < 0.001). Similarly, the Cu/Zn ratio in RHD patients was higher than in control subjects (4.70 +/- 0.92 vs 1.68 +/- 0.45; p < 0.001). Additionally, no significant correlation was found among these trace element concentrations and the functional capacity classes (p > 0.05). RHD patients had decreased serum Se and Zn element concentrations and increased serum Cu element concentration. We suggest that Se and Zn deficiency might be contributory factors in the development of rheumatic heart disease, and a high Cu concentration and a high Cu/Zn ratio might reflect an ongoing inflammatory process in this disease.  相似文献   
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Stripe rust caused by Puccinia striiformis f.sp. tritici is the most serious disease of wheat globally including south‐eastern Anatolia of Turkey, where wheat originated. In this study, 12 spring wheat genotypes were artificially inoculated and preserved in two locations, Diyarbak?r and Ad?yaman, during the 2011–2012 season to investigate loss in yield and yield components. Genotypes were evaluated at the adult plant stage using two partial resistance parameters: final disease severity and area under the disease progress curve (AUDPC). AUDPC ranged from 14.8 to 860 in Diyarbak?r, and 74 to 760 in Ad?yaman. Yield loss ranged from 0.6 to 68.5% in Diyarbak?r and 9.8 to 56.8% in Ad?yaman. Genotypes G1, G5, G7 and G8 were found to lose less yield, while higher yield loss was observed in G3, G4 (Nurkent), G5 and G9 (Karacada?‐98). The highest loss in thousand kernel weight was observed in a susceptible cultivar Karacada?‐98 in Diyarbak?r followed by 43.4 and 24.4% in Ad?yaman. Test weight loss reached 8.89% in Diyarbak?r and 20.8% in Ad?yaman. Yield loss and AUDPC had a positive significant relationship. Based on the values of AUDPC, final disease severity and yield loss, three major clusters were formed for 12 wheat genotypes. Partially resistant genotypes were found to lose less grain yield and seemed to be stronger against severe stripe rust pressure.  相似文献   
9.
The aim of this study was to examine the neurotoxicity of formaldehyde on prefrontal cortex and the protective effects of omega-3 essential fatty acids against these toxic effects. For this purpose, 21 male Wistar rats were divided into three groups. The rats in group I comprised the controls, while the rats in group II were injected every other day with formaldehyde (FA). The rats in group III received omega-3 fatty acids daily while exposed to formaldehyde. At the end of the 14-day experimental period, all rats were killed by decapitation. The brains of the rats were removed and the prefrontal cortex tissues were obtained from all brain specimens. Some of the prefrontal cortex tissue specimens were used for determination of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels. The remaining prefrontal cortex tissue specimens were used for light microscopic and immunohistochemical evaluation. The levels of SOD and GSH-Px were significantly decreased, and MDA levels were significantly increased in rats treated with formaldehyde compared with those of the controls. Furthermore, in the microscopic examination of this group, formation of apoptotic bodies, pycnotic cells, and apoptotic cells including nuclear fragmentation and membrane budding were observed. However, increased SOD and GSH-Px enzyme activities, and decreased MDA levels were detected in the rats administered omega-3 fatty acids while exposed to formaldehyde. Additionally, cellular damage caused by formaldehyde was decreased, and structural appearance was similar to that of the control rats in this group. The biochemical and histological findings observed in all groups were also confirmed by immunohistochemical evaluation. It was determined that formaldehyde-induced neuronal damage in prefrontal cortex was prevented by administration of omega-3 essential fatty acids.  相似文献   
10.
A new soil mite species, Quadroppia (Coronoquadroppia) sezeki sp. n., is described. Adult mites were recorded from moss under a pine tree from a pine forest. The new species differs from the other species of the subgenus by bearing epimera III+IV with a wide key hole shaped inner border and the shape of frontal appendage of rostrum. The morphological features of the new species are also compared with those present in closely related species.  相似文献   
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