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31.
The present investigation reports the novel synthesis of CoWO4 nanoparticles@silk fiber under ultrasound irradiation. The effect of temperature, power of ultrasound irradiation and sequential dipping steps in growth of the CoWO4 particles were studied. Results show a decrease in the particles size as the temperature and power of irradiation decreased. The fibers containing CoWO4 nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity. The results show the CoWO4 nanoparticles@silk with strongest fluorescence characteristics can be obtained in this method. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy.  相似文献   
32.
Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma (ICP). We investigated the uptaking ability of lead (Pb) and cadmium (Cd) by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index (MAI). Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves (2.21) and F. rotundifolia had the highest MAI value for shoots (2.4).  相似文献   
33.
Maintaining and optimising the intestinal barrier (IB) function in poultry has important implications for the health and performance of the birds. As a key aspect of the IB, intestinal permeability (IP) is mainly controlled by complex junctional proteins called tight junction proteins (TJ) that link enterocytes together. The disruption of TJ is associated with increased gut leakage with possible subsequent implications for bacterial translocation, intestinal inflammation, compromised health and performance of the birds. Despite considerable data being available for other species, research on IP in broiler chickens and in general avian species is still an understudied topic. This paper reviews the available literature with a specific focus on IP in broiler chickens with consideration given to practical factors affecting the IP, current assessment methods, markers and nutritional modulation of IP. Several experimental models to induce gut leakage are discussed including pathogens, rye-based diets, feed deprivation and stress-inducing agents such as exogenous glucocorticoids and heat stress. Although various markers including fluorescein isothiocyanate dextran, expression of TJ and bacterial translocation have been widely utilized to study IP, recent studies have identified a number of excreta biomarkers to evaluate intestinal integrity, in particular non-invasive IP. Although the research on various nutrients and feed additives to potentially modulate IP is still at an early stage, the most promising outcomes are anticipated for probiotics, prebiotics, amino acids and those feed ingredients, nutrients and additives with anti-inflammatory properties. Considerable research gaps are identified for the mechanistic mode of action of various nutrients to influence IP under different experimental models. The modulation of IP through various strategies (i.e. nutritional manipulation of diet) may be regarded as a new frontier for disease prevention and improving the health and performance of poultry particularly in an antibiotic-free production system.  相似文献   
34.
This investigation was done to determine the release of potassium (K) from five calcareous soils of southern Iran using 0.025 M CaCl2, HCl and citric acid during six successive extractions and to study the K fixation capacity of the soils after K release experiment. Mineralogical study indicated that Vertisols and Mollisols were dominated with smectites; while other soils had illite, chlorite, palygorskite and smectite. Results indicated that citric acid extracted more K than CaCl2 and HCl (137 vs. 111 and 113 mg kg?1, respectively). The analysis of calcium (Ca), magnesium (Mg) and K concentrations in the solutions suggests that the exchange of K with soluble Ca and Mg (originated from dissolution of carbonates by acidic solutions) is the main mechanism of K release, but citrate is able to dissolve K-bearing minerals and release K in slightly calcareous soils. Soils with more illite released more K. Potassium fixation capacity of soils increased after extractions of soils with different extractants from 324 to 471 mg kg?1, with no significant difference. It is suggested to apply more K fertilizers in K-depleted calcareous soils and use of different solutions for extracting K from soil minerals may be a temporary and short term solution.  相似文献   
35.
A field study was conducted during 2015–2017 in order to evaluate effects of the foliar application of different sources and concentrations of zinc oxide (ZnO) on the yield and morpho-physiological characteristics of saffron. Experimental treatment included the foliar application of nano ZnO at a concentration of (3, 6, and 9 g L?1), foliar application of normal ZnO at a concentration of (3, 6, and 9 g L?1) and the control. Both types of ZnO had positive effects on the saffron yield and number of flowers, but the highest yield and flower number were obtained by the foliar application of 9 g L?1 normal ZnO followed by 6 g L?1 nano ZnO. Increasing concentrations of both fertilizers up to 3 g L?1 had no significant effect on crocin, but the crocin content significantly decreased at higher concentrations. Effects of experimental treatments were significant on all morpho-physiological traits. The maximum chlorophyll a (1.74 mg.g?1) was observed in normal ZnO at a concentration of 9 g L?1 followed by nano ZnO at a concentration of 3 g L?1. The increasing application of different types of fertilizers linearly increased the Peroxidase activity, but the highest activity of Catalase in normal ZnO and nano ZnO was measured after the foliar application at concentrations of 3 and 6 g L?1, respectively.  相似文献   
36.
Temporal land use/land cover (LULC) change information provides a variety of applications for informed management of land resources. The aim of this study was to detect and predict LULC changes in the Arasbaran region using an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis. At the first step, multi-temporal Landsat images (1990, 2002 and 2014) were processed using ancillary data and were classified into seven LULC categories of high density forest, low-density forest, agriculture, grassland, barren land, water and urban area. Next, LULC changes were detected for three time profiles, 1990–2002, 2002–2014 and 1990–2014. A 2014 LULC map of the study area was further simulated (for model performance evaluation) applying 1990 and 2002 map layers. In addition, a collection of spatial variables was also used for modeling LULC change processes as driving forces. The actual and simulated 2014 LULC change maps were cross-tabulated and compared to ensure model simulation success and the results indicated an overall accuracy and kappa coefficient of 97.79% and 0.992, respectively. Having the model properly validated, LULC change was predicted up to the year 2025. The results demonstrated that 992 and 1592 ha of high and lowdensity forests were degraded during 1990–2014,respectively, while 422 ha were added to the extent of residential areas with a growth rate of 17.58 ha per year. The developed model predicted a considerable degradation trend for the forest categories through 2025, accounting for 489 and 531 ha of loss for high and low-density forests, respectively. By way of contrast, residential area and farmland categories will increase up to 211 and 427 ha, respectively. The integrated prediction model and customary area data can be used for practical management efforts by simulating vegetation dynamics and future LULC change trajectories.  相似文献   
37.
The genus Ganoderma Karst. has broad‐spectrum usage in biotechnology, medicine and the food industry. The complexity of the morphology within species has led to uncertain identification in the past, but recent advancements in molecular identification methods have provided scientists with the opportunity to better understand the taxonomy of the species. The present study attempts for the first time to elucidate the distinctiveness of the Ganoderma species growing in Iran concerning those elsewhere in the world based on mitochondrial small subunit ribosomal DNA (mtSSU rDNA) and internal transcribed spacer (ITS) sequence data. The results disclosed that the G. lucidum Karst. samples collected in Iran are more similar to the European Ganoderma species than to the Asian (Chinese) one used in this study.  相似文献   
38.
The aims of this study were to determine vertebral heart size (VHS) in stray cats and to compare different radiographic views. This study was performed on 50 adult stray cats. All cats were short-haired and non-obese and were considered to be healthy based on physical examination and electrocardiography. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken. The long and short axes of the heart were measured in millimetres. The thoracic vertebral length spanned by each dimension was measured caudally from the fourth thoracic vertebra. Mean+/-SD and the correlation coefficient between the measurements were calculated with standard statistical software. The sum of the long and short axes of the heart expressed as VHS was 7.3+/-0.49 vertebrae in right lateral, 7.3+/-0.55 vertebrae in left lateral, 7.5+/-0.68 vertebrae in dorsoventral and 7.5+/-0.53 vertebrae in ventrodorsal. The differences between right and left lateral as well as dorsoventral and ventrodorsal views were not significant (P>0.05). Absolute measurements and vertebral heart scale values were slightly smaller than those reported in the literature for mixed population of cats. It is, therefore, important to take the breed in to account.  相似文献   
39.
Current study was carried out to examine the protective effects of quercetin against toxicity induced by hydrogen peroxide in rooster semen in vitro. Semen samples were collected from ten roosters (Ross 308 broiler breeder males, 32 weeks old) twice a week by abdominal massage method. Samples with ≥70% progressive motility were selected, pooled, diluted and used for the study. Experimental groups consisted of negative control, control that received solvent of quercetin, H2O2 (40 μM) and combination groups which incubated with constant dose of H2O2 (40 μM) plus various levels of quercetin (20, 40 and 80 μM). Measurement of total hydroperoxide (HPO), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (TAC) and superoxide dismutase activity as well as routine sperm tests were done at 0, 24 and 48 hr of storage at 4°C. Results revealed that exposure to hydrogen peroxide significantly increased HPO (138.43 ± 7.32 vs. 66.08 ± 3.97 μmol/g protein), MDA (7.21 ± 0.08 vs. 5.71 ± 2.16 μmol/g protein) and NO (0.367 ± 0.013 vs. 0.215 ± 0.011 μmol/g protein) levels and decreased sperm progressive motility (27.28 ± 1.21 vs. 47.49 ± 1.29%), and amounts of TAC (11.49 ± 0.39 vs. 15.70 ± 0.79 mmol/g protein) compared to control at 24 hr (p < 0.05). Changes at mentioned variables were repeated at 48 hr of storage. Also, co‐administration of quercetin (especially at 40 and 80 μM) with hydrogen peroxide restored the toxic effects of hydrogen peroxide on rooster semen parameters such as primary and secondary lipid peroxidative indicators and other evaluated variables. The study concluded that rooster semen enrichment with quercetin would protect lipid peroxidative and nitrosative hydrogen peroxide‐mediated damage during cold liquid storage of rooster semen.  相似文献   
40.
This study investigated effect of increasing level of dietary sodium using sodium bicarbonate or sodium chloride on growth performance, mortality, characteristics of carcass, organs and tibia, calcium and phosphorus of serum in broilers reared in a high‐altitude area (1,700 m above sea level). A total of 588 Ross 308 male broiler chicks were used in seven treatments, six replicates per treatment of 14 birds per each from 1 to 38 d of age. Seven dietary treatments consisted of a basal diet (with 0.16% sodium and 0.23% chloride), top‐dressed for six diets to give three supplementary levels of sodium (0.07%, 0.14% and 0.21%) from sodium bicarbonate (respectively by 0.26%, 0.52% and 0.78%) or sodium chloride (respectively by 0.18%, 0.36% and 0.54%), resulting in seven diets with total sodium and chloride levels of 0.16% and 0.23%, 0.23% and 0.23%, 0.30% and 0.23%, 0.37% and 0.23%, 0.23% and 0.33%, 0.30% and 0.44%, 0.37% and 0.55% respectively. Increasing sodium level improved feed conversion ratio (FCR) linearly and quadratically. However, when FCR was calculated without adjusting for feed intake of mortalities, the enhanced sodium level did not improve this parameter. Increasing sodium level via sodium chloride enhanced ascites mortality, total mortality, relative weight of heart and right ventricle linearly. Increasing sodium level reduced serum calcium and enhanced serum phosphorus linearly; however, there was a linear tendency to increase tibia ash when sodium level was enhanced by sodium bicarbonate (p = 0.08) or sodium chloride (p = 0.07). Increasing sodium level via sodium bicarbonate tended (p = 0.08) to reduce tibia strength linearly. In conclusion, a diet with 0.16% sodium and 0.23% chloride is enough for broiler chicken reared in a high‐altitude area, and increasing dietary sodium level via sodium chloride has detrimental effect on survivability of broiler in such condition.  相似文献   
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