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21.
In recent year, desertification has become one of the most important environmental hazards all over the world, especially in developing countries such as Iran. Understanding the factors impactingon desertification and identifying the regionswith high desertification potential are essential to control this phenomenon (i.e., desertification). The life cycle assessment (LCA) method is essential in assessing the desertification of ecosystems, especially for susceptible ecosystems with high degradationrisks. The aim of the present study was to evaluate the desertification potential of Lorestan Province, Iran, based on the LCA method. We selected aridity, fire and dust as three indicators of desertification and collected data from 2000 to 2015. We divided the study area into 6 types of ecoregionsaccording to the climate types (arid, semi-arid and dry sub-humid) and dominant species (Quercus brantii and Astragalusadscendens), and calculated the characteristic factor (CF) of eachindicator (aridity, fire and dust) by combining the indicator layers and ecoregion layer of the study area. In a given ecoregion, the sum of CF values of aridity, dust and fire indicators represents the life cycle inventory (LCI) desertification value (the higher the LCI value, the greater the desertification potential).Then, we obtained the desertification potential map by combining and overlapping the ecoregions and the normalized indicators based on the LCA method. Aridity and fire exhibit significant impacts on desertification in the study area compared with dust. In the study area, semi-arid ecoregion with Quercus brantiias the dominant species is the largest ecoregion, while arid ecoregion withQuercus brantiias the dominant species is the smallest ecoregion.Arid ecoregion withAstragalusadscendensas the dominant species (LCI desertificationvalue of 1.99) and dry sub-humid ecoregion withQuercus brantiias the dominant species (LCI desertification value of0.79)show the highest and lowest desertification potentials, respectively. Furthermore, arid ecoregion with Quercus brantii as the dominant species also has a higher LCI desertification value (1.89), showing a high desertification potential. These results suggest the necessity of proper management and appropriate utilization in these ecoregions. In general, assessing desertification potential using the LCA method on a local and regional scale can possibly provide a new methodology for identifying and protecting areas with high degradation risks.  相似文献   
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In this study, the physiological response and growth performances of Acipenser ruthenus were investigated after a long‐term background colour adaptation (12 weeks). Twelve groups of 10 individuals with initial mean body weight of 183 g were reared in black, dark blue, grey and white tanks (three replicates for each colour). At the end of the experiments, growth (initial body weight, final body weight, weight gain per cent, food efficiency ratio, protein efficiency ratio, specific growth rate), blood (cortisol, glucose, pO2, pCO2, pH, haematocrit, osmolality, triglycerides, cholesterol, total lipids) and liver (hepatosomatic index, total lipids, glycogen) parameters were analyzed. Plasma cortisol in the dark‐adapted sterlet (21.95 ± 3.9 ng mL?1) was significantly lower than those in white‐adapted fish (39.44 ± 6.5 ng mL?1), whereas there were no significant differences in cortisol levels between the grey‐adapted fish (23.05 ± 4.1 ng mL?1) and dark blue‐adapted fish (24.2 ± 3.6 ng mL?1). A remarkable increase in mean of body weight (%) was detected in dark‐adapted sterlet (45.2 ± 3.2) being 27.67%, 12.1% and 11.8% higher than the white, grey and dark blue‐adapted fish respectively. The obtained results verified that different background colours lead to different growth performances and physiological responses of starlet, depending on rearing conditions.  相似文献   
24.
The management of an Anterior Cruciate Ligament (ACL) avulsion is principally by surgery. There are two major techniques in this regard; fixation through open surgery (arthrotomy) or arthroscopically-assisted repair. These are not new in the literature; however, the debate regarding the better approach is still under debate. This study focused on comparing outcome and consequences of arthroscopically-assisted vs. open surgery in repairing ACL avulsion. In a randomized clinical trial, 44 patients with unilateral ACL avulsion were recruited in Tabriz Shohada teaching Centre during a 12 month period of time. These patients were randomized in two equal age and sex-matched groups underwent either arthroscopically-assisted or open ACL repair. The constructive technique was the same in both groups without using any graft. The minimum follow-up period was 6 months including 3 weeks, 3 months and 6 months postoperatively. Range of Motion (ROM), laxity, Anterior Drawer Test (ADT) result, duration of hospital stay, wound status, nonunion and return to previous work were compared between the two groups. Mean time of suture removal (p = 0.10), minimum and maximum ROM at months 3 (p = 0.43 and 0.22, respectively) and 6 (p = 0.73 and 0.77, respectively), ADT at months 3 and 6 (p = 0.16 for both), laxity at month 6 (p = 0.28) and wound status at week 3 (p = 0.35) were not significantly different between the two groups. There was no case of nonunion at month 6 in either group. The mean hospital stay was significantly shorter in the arthroscopy group (3.77 +/- 0.92 vs. 2.50 +/- 0.51 days; p < 0.001). The mean laxity score was significantly higher in the open surgery group at month 3 (4.82 +/- 0.59 vs. 4.45 +/- 0.60; p = 0.05). The rate of nonunion was significantly higher in the open surgery group at month 3 (40.9% vs. 9.1%; p = 0.02). Patients in the arthroscopically-assisted technique group returned sooner to previous work (17.41 +/- 1.53 vs. 14.82 +/- 0.96 weeks; p < 0.001). Based on our results, arthroscopically-assisted reconstruction of ACL avulsion is superior to open surgery.  相似文献   
25.
Journal of Plant Diseases and Protection - Pot experiments with winter wheat were conducted for two successive years to study the relationship between the cereal cyst nematode, Heterodera...  相似文献   
26.
From a series of studies on single nucleotide polymorphisms (SNPs) in the bovine growth hormone (GH) gene of Japanese Black cattle, the type‐C (127Val and 172Met) that is specific for this breed has been intensively focused upon because of the economic importance for carcass traits, such as intramuscular oleic acid contents. In the present study, we intended to analyze the 3‐D structure of GH of haplotype C, and developed a novel method to detect the type C gene. Three‐D analysis of the type C protein showed that the amino acid residues (127Val and 172Met), which are present in the third and fourth helixes, respectively, and are important for binding with GH receptors, are shifted to deeper positions in the molecule compared with that for type A (127Leu and 172Thr), implying the alteration of binding interaction with receptors. A novel, efficient and cost‐effective method (Dot‐blot‐SNP technique) for type C genotyping was successfully established, of which the basal method was a reported genotyping of SNPs for a large number of plants, reducing the cost to 10% or less of direct sequencing.  相似文献   
27.
Eurasian Soil Science - Knowledge on P release characteristics and availability of different forms of soil phosphorus can be useful for crop production. Kinetics of P release and distribution of...  相似文献   
28.
A 12‐week feeding trial was conducted to determine a suitable carbohydrate source and form for Pangasianodon hypophthalmus. Ten isoenergetic, isonitrogenous and isolipidic diets, including five carbohydrate sources (dextrin, potato starch, wheat starch, corn starch and sago starch) and two carbohydrate forms (raw and cooked), were formulated. Results showed that specific growth rate, weight gain percentage, whole‐body lipid and 6‐phosphogluconate dehydrogenase enzyme activity of fish fed with cooked carbohydrates were significantly lower (p < .05) than those fed with raw carbohydrates (p < .05). Similarly, the fatty acid synthase enzyme activity of fish fed with the cooked form of carbohydrates was significantly lower (p < .05) than that fed with the raw form of carbohydrates except fish fed with cooked potato starch. The blood glucose level and malic enzyme activity of fish fed with cooked carbohydrate were significantly (p < .05) higher than those fed with raw carbohydrate. In summary, this study showed that cooked starch is an unsuitable dietary carbohydrate form for Pangasianodon hypophthalmus fingerlings. The raw forms of dextrin starch and potato are suitable dietary carbohydrate sources for further scientific studies on the carbohydrate utilization of P. hypophthalmus.  相似文献   
29.
Fat‐tailed sheep breeds can tolerate periods of negative energy balance without suffering from elevated concentration of plasma non‐esterified fatty acid (NEFA). This ability was attributed to unique metabolism of fat‐tailed adipose depot, whereas role of liver as an influential organ in fatty acid metabolism was not evaluated yet. Hence, current study was conducted to evaluate the effects of negative and positive energy balances on liver expression of genes related to fatty acid metabolism in fat‐tailed and thin‐tailed lambs. Lambs experienced negative (21 days) and positive (21 days) energy balances and were slaughtered at the beginning and end of negative energy balance and at the end of positive energy balance. Real‐time quantitative polymerase chain reaction (RT‐Q‐PCR) was conducted to evaluate changes in gene expression. Expression of diglyceride acyltransferase 1 (DGAT1), 3‐hydroxy‐3‐methylglutaryl‐CoA synthase 2 (HMGCS2) and apolipoprotein B (APOB) was not affected by genotype, energy balance and their interaction. Expression of carnitine palmitoyltransferase 1 (CPT1) was significantly higher in liver of fat‐tailed comparing to thin‐tailed lambs regardless of energy balance (p < 0.02). Catalase mRNA abundance was increased in response to negative energy balance (p < 0.02), and severity of this enhancement was higher in fat‐tailed lambs (p < 0.06). Expression of CPT1 was positively correlated with expression of HMGCS2 in both fat‐tailed (p < 0.05) and thin‐tailed lambs (p < 0.002); however, the correlation was weaker in fat‐tailed lambs (0.72 vs. 0.57, respectively, for thin‐tailed and fat‐tailed lambs). There was a positive correlation between DGAT1 and APOB genes expression in fat‐tailed lambs (0.94; p < 0.001), whereas this correlation was not observed in thin‐tailed lambs. Results demonstrate that liver of fat‐tailed lambs has higher capacity for metabolism of mobilized NEFA exposed to liver during negative energy balance.  相似文献   
30.
This is the first report of an acephalous lamb from the transfer of an in vitro-produced sheep embryo. Twelve in vitro-fertilized embryos were transferred to 4 recipient ewes (3 embryos/ewe). Two ewes remained pregnant: one delivered a normal female lamb, the other a male acephalous lamb. Possible contributing factors are discussed.  相似文献   
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