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81.
The chemical composition of essential oil isolated by hydrodistillation from the leaves of Tunisian Eucalyptus erythrocorys Linn. was analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC/MS). Fifteen compounds were identified, representing 97 % of total oil, which was found to be rich in oxygenated monoterpenes (66.7 %), particularly in 1,8-cineole (54.8 %). The yield and the physico-chemical properties of oil were determined. The study of antifungal activity revealed that E. erythrocorys essential oil significantly inhibited the growth of five plant pathogenic fungi especially Bipolaris sorikiniana and Botritys cinerea. Moreover, herbicidal properties of the oil, tested on Sinapis arvensis L. and Phalaris canariensis L. indicated that the E. erythrocorys oil completely inhibited the seed germination at high concentration (1.5 μl/ml), while at low doses (0.25, 0.5, 0.75, 1 μl/ml) the oil acted by decreasing and delaying the germination and inhibiting the seedling growth of all tested weeds.  相似文献   
82.

Background  

Restless Legs Syndrome (RLS) is a common neurological movement disorder characterized by symptoms that follow a circadian pattern. Night and rotating shift work schedules exert adverse effects on functions of the human body by disturbing circadian rhythms, and they are known to cause sleep disturbances and insomnia. In this paper, we investigate the possible association between shift work and RLS.  相似文献   
83.
The present study was carried out to investigate the effect of sublethal zinc (Zn) concentrations on growth performance, biochemical variables, and Zn residues in various organs of Nile tilapia, Oreochromis niloticus (L.). Fish (25 ± 0.5 g) were exposed to 0.0, 3.5, or 7.0 mg Zn L?1 for 1 or 6 weeks. Fish growth was significantly reduced with increasing Zn concentrations. However, fish exposed to 7.0 mg Zn L?1 grew less quickly than those of the control group. Likewise, best feed intake and feed conversion ratio were obtained at the control group. Furthermore, glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and cortisol increased significantly with increasing Zn concentrations and exposure time, with maximal values in the 7.0 mg Zn L?1 treatment after 6 weeks. Meanwhile, highest values of serum protein and lipids were obtained in the control fish reared for 6 week, whereas their lowest values were observed in fish exposed to 7.0 mg Zn L?1 for 1 week. There was no significant change in whole-body moisture content of fish due to Zn exposure, although crude protein and total lipid contents decreased significantly with increasing Zn concentrations. In addition, Zn exposure increased total ash contents and Zn residues in different investigated fish organs. The Zn concentrations in all fish organs were time-dependant and the Zn residues after 1 week were found to follow the order of gills > liver > kidney > muscle, meanwhile after 6 weeks it followed the order of liver > kidney > gill > muscle. The present findings revealed that liver and kidney tissues are the prime sites of Zn bioaccumulation, while Zn load in the muscle was for low as compared to other organs.  相似文献   
84.
Field experiments were conducted in 2010 and 2011 at the Agricultural College of Shiraz University to evaluate the effects of cattle manure and nitrogen (N) fertilizers on soil properties such as soil organic carbon (SOC), soil organic nitrogen (SON), soil electrical conductivity, soil pH and corn yield under two tillage systems. Treatments included tillage systems in two levels as conventional tillage and reduced tillage as subplots, cattle manure (0, 25 and 50 tons ha?1) and N fertilizer (0, 125 and 250 kg N ha?1) as sub-subplots. Results showed that SOC and SON were significantly affected by tillage system in both years of the experiment. SOC and SON were higher in reduced tillage compared to conventional tillage. Tillage system had no significant effect on grain yield, plant height and 1000 seed weight. Increased cattle manure rates at 25 and 50 tons ha?1 increased grain yield by 27% and 38%, respectively, in 2010 and 25% and 25% in 2011. The results showed that application of cattle manure combined with N fertilizer might be an efficient management to increase soil productivity in southern Iran, in soils with poor organic content. Additionally, reduced tillage showed to be an efficient method to increase soil organic matter.  相似文献   
85.
86.
In 2012, a greenhouse experiment was conducted to investigate the effects of field soil (C0), residual composted municipal waste (CMW), and residual composted sheep manure (SM) on the growth of triticale in pots previously growing oilseed rape in 2011. To each soil group, one of three levels of urea nitrogen (N) fertilizer was added. Results demonstrated that triticale grown in pots previously containing oilseed rape plants containing SM or CMW with 150 kg urea N ha?1 had the highest N content. Plants grown in SM with 150 kg N ha?1 had the greatest seed yield, but yield was not significantly different from plants grown in CMW receiving 150 kg N ha?1. Triticale plants enriched by either SM or CMW had a higher amount of N, copper, zinc, and manganese compared to the field soil control.  相似文献   
87.
Genome-wide association studies (GWAS) have introduced an influential tool in the search for quantitative trait loci (QTL) influencing economically important traits in sheep. To identify QTL associated with greasy fleece weight, a GWAS with 50 K single nucleotide polymorphisms (SNPs) was performed in a Baluchi sheep population. Association with greasy fleece weights was tested using the software Plink. The results of our GWAS provided three novel SNP markers and candidate genes associated with greasy fleece weight. A total of three chromosome-wide significant associations were detected for SNP on chromosomes 17 and 20 affecting greasy fleece weight across the four shearing. One of the significant SNP markers was located within ovine known genes namely FAM101A. Further investigation of these identified regions in validation studies will facilitate the identification of strong candidate genes for wool production in sheep.  相似文献   
88.
The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability of the Mazandaran native fowls in Iran by quantifying the pedigree completeness index, effective population size, genetic diversity, inbreeding level, and individual increase in inbreeding. The pedigree completeness analysis showed 3.31 full, 10.19 maximum, and 6.30 equivalent generations. The effective number of founders (f e) was 131, representing 5% of the potential number of founders. The effective number of ancestors (f a) was 81, and the genetic contribution of the 37 most influent ancestors explained 50% of the genetic variability in the population. The ratio f e/f a (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.62. The inbreeding coefficient increased over generations and the average was 1.93%. The average relatedness coefficient between individuals of the population was estimated to be 2.59%. The effective population size, based on the number of full generations, was 56. Family size analysis showed that fewer males than females were used, resulting in the observed levels of inbreeding. Average inbreeding coefficient in the Mazandaran native fowls can be regarded to be below critical levels. However, considering the relationship coefficients of individuals is recommended to aid maintaining genetic diversity of Mazandaran native fowls.  相似文献   
89.
The present study was carried out to evaluate the effect of dietary taurine (Tau) on performance, digestive enzymes, antioxidant activity, and resistance of common carp, Cyprinus carpio L., fry to salinity stress. Fish (0.97?±?0.033 g) were fed on different taurine levels of 0.0 (control), 5, 10, 15, or 20 g/kg diet up to satiation twice daily for 8 weeks. At the end of the feeding trial, fish were stressed by exposure to 10 ppt salinity for 3 days during which fish mortality was observed. Fish performance was significantly (P?<?0.05) improved by dietary taurine up to 15 g Tau/kg diet after which fish growth and feed intake were almost the same. Also, taurine supplementation significantly (P?<?0.05) elevated activities of intestinal amylase, lipase, and protease resulting in an improving in feed intake giving better performance. Furthermore, Tau-stimulated antioxidant activity of common carp was observed in a dose-related manner, where activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were significantly (P?<?0.05) higher, but malondialdehyde (MDA) value was significantly (P?<?0.05) lower in Tau-fed fish groups than those fed the control diet. In salinity stress experiment, highest survival rate was observed at fish fed Tau-supplemented diets without significant (P?>?0.05) differences over fish fed the control diet. It appears that taurine could be used as a feed supplement to confer better growth and health of common carp fry with optimal level of 15 g/kg diet.  相似文献   
90.
Most of world's forests of different climates have a history of fire, but with different severities. Fire regimes for broadleaf deciduous forests have return intervals that vary from many decades (or less) to centuries (or more). Iran has a total of 1.2 million ha of temperate forest in the north, where fires burn about 300–400 ha annually. This study focused on the impact of fire on forest structure, tree species quality, and regeneration composition (specially beech) in the Chelir forest of northern Iran. The results showed that forest fires changed the structure and had different effects on tree species composition between burned and control areas. Thin barked species such as oriental beech (Fagus orientalis Lipsky) and coliseum maple (Acer cappadocicum Gled.) have been affected more than those with thick bark, like hornbeam (Carpinus betulus L.) and chestnut-leaved oak (Quercus castaneifolia C.A. Mey). The density of oriental beech regeneration in the unburned area was greater than in the burned area, while the quantity of regeneration of hornbeam, coliseum maple and velvet maple (Acer velutinum Boiss) was higher in burned area. Forest fire had a greater effect on oriental beech quality, and changed regeneration composition in the burned area. Fire prevention activities should be considered as a silvicultural treatment for preserving these valuable forests.  相似文献   
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