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1.
A 5‐week study was performed to evaluate the effect of spoilage date extract (SDE) as the biofloc carbon source on Litopenaeus vannamei (5.4 ± 0.3 g) performance. The two levels of dietary protein (15% and 25% crude protein) and two carbohydrate sources (molasses‐M and SDE‐P) were tested including: M15, M25, P15 and P25. The minimum (0.2 ± 0.0 mg/L) and the maximum (0.5 ± 0.0 mg/L) of total ammonia nitrogen were observed in the P15 and M25 groups respectively. The highest protein efficiency ratio (6.1 ± 0.3) and protein productive value (112.3 ± 5.8%) were found in the P15 group (p < 0.05). No significant difference was found between biofloc treatments in the expression of cathepsin L gene in hepatopancreas (p > 0.05). The number of total haemocyte count (THC), semigranular cells (SGC) and granular cells (GC) of shrimp in SDE‐based biofloc treatments was relatively higher than those in molasses‐based biofloc treatments. Following the white spot syndrome virus (WSSV) challenge, a significant decrease in THC, SGC, GC and hyaline cell values was observed in all treatments (p = 0.001). Plasma biochemical parameters were significantly influenced by dietary protein levels, biofloc carbon sources as well as WSSV challenge test. In conclusion, SDE successfully could be used as an alternative carbon source for establishing a biofloc system in L. vannamei production.  相似文献   
2.
High quality fruit production is the cornerstone of marketability. Optimum plant performance depends on the balanced and timely availability of mineral nutrients. In addition to element concentrations, the ratio of nutrient elements in solution plays a determinative role in growth, productivity, quality, and nutrients uptake. In this experiment, the effects of different Potassium:Calcium (K:Ca) ratios (1.6, 1.4, 1.2, 1, 0.85, and 0.6) in nutrient solution were studied on quality attributes of strawberry ‘Selva’. The highest and lowest leaf number and leaf area were observed in K:Ca 1.4 and 1, respectively. The highest fruit pH, electrical conductivity, total soluble solids/titratable acidity ratio, vitamin C content, ellagic acid, and color were resulted in K:Ca (1.4) ratio. K:Ca (1.6) ratio produced the highest content of protein. Moreover, K:Ca (0.85) ratio was the most effective treatment on fruit firmness. The increased quality attributes were observed in high K:Ca ratios, hence low K:Ca ratio resulted in increased fruit firmness. In conclusion, nutrient solution containing K:Ca ratios between 1 and 1.6 were suitable for producing strawberry ‘Selva’. Taken together, K:Ca (1.4) was an appropriate ratio for producing strawberry ‘Selva’ in soilless culture with coconut fiber: perlite medium.  相似文献   
3.
The main objective of this study was to evaluate the potential use of a hybrid Genetic Algorithm-Artificial Neural Network (GA–ANN) method for predicting pistachio yield and for identifying the determinant factors affecting pistachio yield in Rafsanjan region, Iran. A total of 142 pistachio orchards were selected randomly and soil samples were taken at three depths. Besides, water samples and leaves from branches without fruit were taken in each sampling point. Management information and pistachio yields were achieved by completing a questionnaire. Primarily, 58 variables affecting pistachio yield were measured, and then 26 out of them were selected by minimizing mean square error (MSE) using a feature selection (FS) method. The results showed that the accuracy of the method was acceptable. Furthermore, the sensitivity analysis showed that the main determinant features affecting the pistachio yield were the irrigation water amount, leaf phosphorus, soil soluble magnesium, electrical conductivity (EC), and leaf nitrogen.  相似文献   
4.
Global warming is one of the most complicated challenges of our time causing considerable tension on our societies and on the environment. The impacts of global warming are felt unprecedentedly in a wide variety of ways from shifting weather patterns that threatens food production, to rising sea levels that deteriorates the risk of catastrophic flooding. Among all aspects related to global warming, there is a growing concern on water resource management. This field is targeted at preventing future water crisis threatening human beings. The very first stage in such management is to recognize the prospective climate parameters influencing the future water resource conditions. Numerous prediction models, methods and tools, in this case, have been developed and applied so far. In line with trend, the current study intends to compare three optimization algorithms on the platform of a multilayer perceptron (MLP) network to explore any meaningful connection between large-scale climate indices (LSCIs) and precipitation in the capital of Iran, a country which is located in an arid and semi-arid region and suffers from severe water scarcity caused by mismanagement over years and intensified by global warming. This situation has propelled a great deal of population to immigrate towards more developed cities within the country especially towards Tehran. Therefore, the current and future environmental conditions of this city especially its water supply conditions are of great importance. To tackle this complication an outlook for the future precipitation should be provided and appropriate forecasting trajectories compatible with this region's characteristics should be developed. To this end, the present study investigates three training methods namely backpropagation (BP), genetic algorithms (GAs), and particle swarm optimization (PSO) algorithms on a MLP platform. Two frameworks distinguished by their input compositions are denoted in this study: Concurrent Model Framework (CMF) and Integrated Model Framework (IMF). Through these two frameworks, 13 cases are generated: 12 cases within CMF, each of which contains all selected LSCIs in the same lead-times, and one case within IMF that is constituted from the combination of the most correlated LSCIs with Tehran precipitation in each lead-time. Following the evaluation of all model performances through related statistical tests, Taylor diagram is implemented to make comparison among the final selected models in all three optimization algorithms, the best of which is found to be MLP-PSO in IMF.  相似文献   
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6.
Crop production in arid/semi-arid regions is restricted by soil moisture and nitrogen (N) deficiencies. Consequently, sufficient levels of N and irrigation are important in improving the crop's productivity. Therefore, a 2-year field experiment was conducted to understand influences of watering techniques namely 300, 500 and 700 mm with contrasting N supply (0, 60, 120 and 180 kg ha?1) on wheat cv. “landrace” productivity, dry matter translocation (DMT) and contribution of pre-anthesis assimilates to the grain (CPAAG, %). Experiments were conducted each year using a split-plot design with three replications at a private farm, North Hamedan Province, Iran. Accordingly, when 500/700 mm water was applied, CPAAG values were higher than those obtained after applying 300 mm water, i.e. 49.99 and 45.45 vs. 40.13%. The highest productivity in terms of grain yield, grain N concentration, nitrogen harvest index, special products analysis division and protein content was achieved in normal deficiencies of irrigation and N. This was further supported by a higher leaf area index, crop growth rate and N uptake of such treatment. Meanwhile, co-application of 120 kg N and 500 mm water significantly improved DMT, water and N use efficiency, and it was the optimal scheme for wheat production.  相似文献   
7.
Renewable energies as well as saving energy in suitable forms are of great challenges in the field of energy storage. Phase change materials (PCM) are one of the latent heat storage materials. They can produce high density of energy storage during phase change. However, there is a risk of material leakage during their phase change. Electrospinning could lead to thermo-regulating nanofibers of leakage free form-stable PCMs. For this purpose, polyethylene glycol (PEG) 6000 as a PCM together with nylon 6,6 as supporting material was electrospun in different blend ratios. Morphology and diameter of the produced nanofibers were studied by Scanning Electron Microscope (SEM). The average nanofibers diameter was in the range of 178 to 507 nm for different blend ratios. Differential scanning calorimetry (DSC) results showed that the composite samples have high heat capacity and good energy saving properties. As-spun nanofibers were successfully changed to a formstable thermo-regulating nanocomposite using a suitable cross-linking agent.  相似文献   
8.
Background: Brain hypoxia-ischemia is a human neonatal injury that is considered a candidate for stem cell therapy. Methods: The possible therapeutic potential of human umbilical cord blood (HUCB) stem cells was evaluated in 14-day-old rats subjected to the right common carotid occlusion, a model of neonatal brain hypoxia-ischemia. Seven days after hypoxia-ischemia, rats received either saline solution or 4 × 105 HUCB cells i.v. Rats in control group did not receive any injection. After two weeks, rats were assessed using two motor tests. Subsequently, rats were scarified for histological and immunohistochemical analyses. Results: Our immunohistochemical findings demonstrated selective migration of the injected HUCB cells to the ischemic area as well as reduction in infarct volume. Seven days after surgery, we found significant recovery in the behavioral performance in the test group (12.7 +/- 0.3) compared to the sham group (10.0 +/-0.05), a trend which continued to day 14 (15.3 ± 0.3 vs. 11.9 ± 0.5, P<0.05). Postural and motor asymmetries at days 7 and 14 in the test group showed a significant decrease in the percentage of right turns in comparison to the sham group (75% and 59% vs. 97% and 96%, P<0.05). Conclusion: The results show the potential of HUCB stem cells in reduction of neurologic deficits associated with neonatal hypoxia-ischemia. Key Words: Hypoxia-Ischemia, Nerve cell, Umbilical Cord Blood  相似文献   
9.
BACKGROUND: Busulfan, a cytotoxic drug, which is currently used as a chemotherapeutic agent, has many side effects on different body organs. In this research, the effects of busulfan on sperm parameters and microstructure of mouse testis were investigated. METHODS: Busulfan was injected intrapretoneally at 10, 20, 30, 40 and 50 mg/kg and testes were removed after 4, 6 and 8 weeks, weighed and processed for light microscopic examination. Transverse and cross section diameters of testes, seminiferous tubules diameters, percentage of different types of tubules, epithelium thickness, spermatogenic cell numbers and capsule thickness as well as the sperm parameters in epididymis were measured. RESULTS: There was a significant decline in sperm numbers and marked changes in testes structures. Almost 8 weeks after the injection of drug, some of the changes are reversed. Accordingly, the changes in percent of normal tubules without sperm, abnormal tubules and capsule thickness were increased until 6 weeks of drug administration, the changes declined thereafter. CONCLUSION: In general, busulfan caused a decrease in all analyzed parameters (except capsule thickness, normal tubules without sperm and abnormal tubules), probably due to the arrest of spermatogenesis. Our results also revealed that some of the changes are reversible and dose dependent.  相似文献   
10.
N,N-Diethyl-m-toluamide (DEET) is widely used as an insect-repellent. Sulfonamides are an important class of anti-bacterial drugs. In order to combine the strength of anti-bacterial activities of sulfonamides and insect-repellent property of DEET, three azo reactive dyes were designed and synthesized. To do this, the diazoniom salts of sulfonamides viz. 4-amino-N-(4-methyl-2-pyrimidinyl) benzene sulfonamide, 4-amino-N-(4-dimethyl-2-pyrimidinyl) benzene sulfonamide and 4-amino-N-(4,6-dimethyl-2-pyrimidinyl) benzene sulfonamide were prepared using HCl and NaNO2. The resulting diazoniom salts were then coupled to the coupling component containing N,N-diethyl-m-toluamide to produce the novel dyes. The synthesized dyes were filtered off and then purified. To investigate and analyze the dyes, analytical methods such as 1H-NMR, FTIR, UV-visible spectroscopy, and elemental analysis were used. Consequently, the anti-bacterial activities of dyes were measured with E. coli and P. aeruginosa as a Gram-negative strain and S. aureus and S. mutans as a Gram-positive strain according to MIC method. The insect-repellent efficacy of the dyes was studied using standard methods for Anophle mosquito repellent. The results confirmed anti-bacterial and insect-repellent activity of the dyes.  相似文献   
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