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1.
The development of genotypes with adaptation to a wide range of environments is one of the most important goals of plant breeding programs. In order to compare nonparametric stability measures and to identify promising high-yield and stable barley (Hordeum vulgare L.), 20 barley genotypes selected from the Iran/ICARDA joint project and grown in nine environments during 2009-11 in Iran. Four nonparametric statistical tests of significance for genotype × environment (GE) interaction and 10 nonparametric measures of stability were used to identify stable genotypes in nine environments. Results of nonparametric tests of G×E interaction (Kubinger, Hildebrand, and Kroon/ Laan) and a combined ANOVA across environments, indicated the presence of both crossover and non-crossover interactions. Also, only TOP and rank-sum values were positively associated with high yield. Thus, in the simultaneous selection for high yield and stability, only the rank-sum and TOP methods were useful in terms of the principal component analysis results, and correlation analysis of nonparametric stability statistics and yield. According to these stability parameters (TOP and rank-sum), three genotypes (G13, G12, and G17) were the most stable for grain yield. The results also revealed that based on nonparametric test results, stability could be classified into three groups, according to agronomic and biological concepts of stability.  相似文献   
2.

The current study was conducted to evaluate the effects of increasing carbon to nitrogen (C/N) ratios on water quality, growth performance, and body composition of Litopenaeus vannamei juveniles. Shrimp with initial average weight of 2.50?±?0.3 g were cultivated for 35 days in 300-L tanks (160 L of water volume) with a density of 1 g per liter. The experiment was performed in five treatments with three replicates. One control group and four biofloc treatments with different C/N ratio were considered: C/N of 10 (CN10), 14 (CN14), 18 (CN18), and 22 (CN22). Shrimp were fed three times a day, and molasses just was added as a carbon sources to the biofloc treatments after each feeding. According to the results, the lowest amount of dissolved oxygen (5.33 mg L?1) and pH (7.83) was observed in CN22 treatment, which showed a significant difference with other treatments (P?<?0.05). The highest level of total ammonia nitrogen (1.05 mg L?1) and nitrite (mg L?1) were recorded in control group, while the highest total density of heterotrophic bacteria was obtained in CN22 treatment. Growth performance parameters were at the highest level in the CN14 treatment, so the highest amount of final weight (6.88 g), biomass, and survival rate (94.79%) were observed in this treatment. The biochemical composition (protein, lipid, and ash) of the shrimp body and produced biofloc were affected by different C/N ratios, so these parameters were increased by rising of C/N ratio. In general, this study showed that the growth performance and body composition of Pacific white shrimp juveniles and water quality were suitable for rearing in biofloc system with C/N ratio of 14 than other treatments.

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3.
Iran supports five different vegetation zones. One of those is the Irano-Touranian zone that is located in the northeast of Iran. This vegetation zone includes arid and semi-arid lands, and its area is about 3.5 million hm2. It supports growth of pistachio (Pistacia vera), a deciduous-broadleaved species, which is one of the ecologically and economically most important native species. In this study, we analyzed three images acquired by ALOS satellite, including 10m resolution multispectral band (AVNIR-2), 2.5 m resolution “Backward” PRISM image, and 2.5 m resolution “Nadir” PRISM image, based on a provided rational polynomial coefficient (RPC). Using the “Backward” and “Nadir” images, a 2.5 m resolution digital elevation model (DEM) was produced. Four methods with AVNIR-2 and PRISM data were used to produce pan-sharpening images and conduct an object-based feature extraction process. Normalized Difference Vegetation Index (NDVI) was used to determine the maximum distribution of pistachio in related elevation. The accuracy of the DEM was tested on 28 ground control points in the pair image as tie points, with the value of parallax error of 0.9027 m. The created elevation map indicated that pistachio trees grow up at 650m above sea level (a.s.l.). The result from NDVI in the related elevation showed the maximum density of pistachio at 800m a.s.l. In addition, the result of feature extraction in the forest showed the area of each target element calculated. The results of this research will improve decision-making and lead to sustainable management in general.  相似文献   
4.
Various classes of medication are currently being used in Polycystic Ovary Syndrome (PCOS) patients including the biguanides and the statins. However, their efficacies are rarely compared. This study aimed to compare efficacy ofa biguanide and a statin in treating PCOS. In a randomized double-blind clinical trial, 400 women with PCOS were recruited within 15 months in Taleghani Hospital. They randomly received either a biguanide (metformin 500 mg three times daily) or a statin (simvastatin 20 mg daily) for three consecutive months. Changes of clinical and laboratory variables were compared. In the biguanide group the serum glucose status (abnormal fasting and non-fasting sugar and insulin levels and percentage of hyperinsulinemic cases) and menstrual abnormalities improved significantly after treatment (p < 0.05). In the statin group the lipid profile status (abnormal total cholesterol, high and low density lipoproteins), C-Reactive Protein (CRP), serum dehydroepiandrosterone sulfate, hyperinsulinemia, severity of acne and menstrual abnormalities improved significantly after treatment (p < 0.05). Comparing the two groups, the improvements in fasting blood sugar and serum insulin levels were significantly better in the biguanide group (p = 0.04 for both parameters); whereas the improvements in serum total cholesterol (p < 0.001), low density lipoprotein (p < 0.001), CRP (p < 0.001) and acne status (p = 0.04) were significantly superior in the statin receivers. Based on these results, each medication is only effective on some aspects of the disease. Overall, the simvastatin was superior to metformin with regard to the number of beneficial effects.  相似文献   
5.
This study aimed to evaluate color Doppler sonographic findings in carotid arteries in RA patients under pharmacological treatments and to compare them with normal population. Forty nine patients with late RA and 48 healthy age and sex-matched controls were recruited. The two groups were matched for other known risk factors of atherosclerosis including serum lipid abnormalities, smoking status, diabetes mellitus and hypertension. High resolution B-mode color Doppler ultrasound with a 7 MHZ transducer was used for measuring the Common Carotid Intima-Medial Thickness (CCIMT) in both sides in all subjects. Presence of atherosclerotic plaque was also investigated. The mean left and maximum CCIMT was significantly higher in the case group (0.72 vs. 0.62 mm for the left artery; p < 0.01; 0.72 vs. 0.64 mm for the maximum reading; p = 0.01). No atherosclerotic plaque was found in common carotid arteries. There were 3 (6.1), 7 (14.3) and 9 (18.4%) plaques in left internal carotid artery, right carotid bulb and left carotid bulb in the case group, respectively with no atherosclerotic plaques in the controls (p = 0.24, 0.01 and < 0.001, respectively). Comparing the findings by gender in the case group with the controls, the mentioned significant differences were only between the male patients and the controls. The process of atherosclerosis in RA patients is similar to that in normal population. However, it is apparently accelerated and more advanced in these patients.  相似文献   
6.
Synthesis of biocompatible polymer nanofibers is valuable, due to their use as a cover for burns and as a replacement for bandage because of their antimicrobial properties. In this study, electrospinning of chitosan(Ch) and nanofibers synthesis with antibacterial properties was investigated. Nanofibers with antibacterial properties were synthesized by electrospun of Ch/poly(L-lactide)(PLA)/Imipenem(Imi) polymer solution. The results showed that the optimized ratio of Ch/PLA polymer solution was ratio of 50:50 and Ch 2 wt% and PLA 10 wt% polymer solution was the best weight percentage for nanofiber preparation. Also, the average diameter of Ch/PLA/Imi nanofibers was 143 nm and measured with ImageJ software. Afterwards, the antibacterial properties of Imi as additives (with different percentages) was studied in the polymer solution. The scanning electron microscopy (SEM) images and antibacterial tests were showed that the electrospun of Ch/PLA/Imi polymeric nanofibers were effective against Gram negative bacteria Escherichia coli (E. coli) and inhibited growth of E. coli. The growth and viability percentage of fibroblast cells with nanofibers in αMEM culture are at desirable levels after 6 days.  相似文献   
7.
We investigated procurement of raw materials for particleboard to minimize costs and develop an efficient optimization model for product mix.In a multiple-vendor market,vendors must be evaluated based on specified criteria.Assuming sourcing from the highest-scoring vendors,annual purchase quantities are then planned.To meet procurement needs,we first propose a model to describe the problem.Then,an appropriate multi-criteria decision making(MCDM) technique is selected to solve it.We ran the model using commercial software such as LINGO and then compared the model results to a real case involving one of the largest particleboard manufacturers in the region.The model run based real data yielded a procurement program that is more efficient and lower in cost than the program currently in use.Use of this procurement modelling approach would yield considerable financial returns.  相似文献   
8.
The Common Carotid artery Intima-Media Thickness (CCIMT) can reflect systemic atherosclerosis in renal patients on hemodialysis. This study aimed to compare CCIMT measured by color Doppler ultrasonography between two groups including dialytic patients and normal subjects. In this case-control setting, 48 patients with Chronic Kidney Disease (CKD) on hemodialysis (case group) and 46 age and sex-matched healthy subjects (control group) were enrolled in this study. Color Doppler ultrasound was used to measure CCIMT and determine presence of atherosclerotic plaques in carotid bulb in both groups. Various laboratory parameters were also determined. Serum levels of triglyceride, total cholesterol, low-density lipoprotein, fasting sugar, ionized calcium, inorganic phosphorus and magnesium were comparable between the two groups. Hypertension and elevated levels of serum C-reactive protein, as well as the mean levels of serum non-fasting homocysteine and phosphate were significantly higher in the case group. Mean levels of serum high-density lipoprotein and albumin were significantly higher in the controls. Mean maximum CCIMT was significantly higher in the case group than in controls (0.73 +/- 0.15 vs. 0.68 +/- 0.08 mm, p = 0.01) even after adjusting for other confounding variables. Frequency of patients with atherosclerotic plaques in carotid bulbs was not significantly different between case and controls. In conclusion, this study showed that CCIMT is significantly higher in CKD patients on hemodialysis comparing with matched normal counterparts. Furthermore, this difference was independent of other conventional risk factors for atherosclerosis.  相似文献   
9.
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   
10.
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