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1.
In recent years, with development and validation of different genotyping panels, several methods have been proposed to build efficient similarity matrices among individuals to be used for genomic selection. Consequently, the estimated genetic parameters from such information may deviate from their counterpart using traditional family information. In this study, we used a pedigree-based numerator relationship matrix ( A ) and three types of marker-based relationship matrices () including two identical by descent, that is and and one identical by state, as well as four Gaussian kernel () similarity kernels with different smoothing parameters to predict yet to be observed phenotypes. Also, we used different kinship matrices that are a linear combination of marker-derived IBD or IBS matrices with A, constructed as , where the weight () assigned to each source of information varied over a grid of values. A Bayesian multiple-trait Gaussian model was fitted to estimate the genetic parameters and compare the prediction accuracy in terms of predictive correlation, mean square error and unbiasedness. Results show that the estimated genetic parameters (heritability and correlations) are affected by the source of the information used to create kinship or the weight placed on the sources of genomic and pedigree information. The superiority of GK -based model depends on the smoothing parameters (θ) so that with an optimum θ value, the GK -based model statistically yielded better performance (higher predictive correlation, lowest MSE and unbiased estimates) and more stable correlations and heritability than the model with IBD, IBS or kinship matrices or any of the linear combinations.  相似文献   
2.
The effect of five different light regimes on growth, stress and hematological indices was studied in Persian sturgeon, Acipenser persicus. Fish with average weight of 645.3 ± 11.2 g were subjected to different photoperiods (24 L, 12 L:12 D, 16 L:8 D, 8 L:16 D and 24 D) for 8 wk. Blood samples were collected at the end of the experiment for measuring cortisol, glucose and hematological features. The whole growth parameters showed no significant difference. Plasma cortisol concentration was significantly higher in 12 L:12 D, while the lowest level was observed in fish exposed to 24 D. No significant changes were observed among the treatments for glucose concentration. Lactate concentration varied significantly among the treatments. Some hematological indices including hematocrit and number of white blood cells were affected by different light regimes, but the others (hemoglobin and number of red blood cells) were not affected significantly. The results showed that photoperiod manipulation can alters some stress‐related metabolites and may enhance growth rate in fish exposing to continuous darkness.  相似文献   
3.
Background: The progressive accumulation of misfolded and aggregated proteins in neurons is an accepted mechanism in aging. Overproduction of reactive oxygen species (ROS), referred to as oxidative stress, is currently believed to play a pivotal role in this process. Lipofuscin as a histological index of aging results from cross-links between oxidized proteins and lipids. Therefore, to attenuate lipofuscin formation, it would be logical to use exogenous natural or synthetic antioxidants. Yakuchinone B (1-[4''-hydroxy-3''-methoxyphenyl]-7-phenylhept-1-en-3-one) is a component of Alpinia oxyphylla seeds with established antioxidant activity. Methods: To evaluate the neuroprotective roles of yakuchinone B (JC6) and its structural analogues (JC1-JC5), the free radical scavenging capabilities of yakuchinone B derivatives were studied in terms of cell viability, apoptosis, cells ROS content, catalase (CAT) and superoxide dismutase (SOD) activity and the intracellular lipofuscin content in SK-N-MC cells exposed to H2O2. The level of MDA (malondialdehyde), as an index of lipid peroxidation and acid phosphatase activity were also measured. Results: Our results indicated that derivatives especially JC4, JC5 and JC6 decreased the extent of apoptosis and ROS level, while they increased the activities of SOD and CAT in drug-pretreated cells as compared to H2O2-treated cells. A clear relationship between the structure and antioxidant activities of these compounds was established. In addition, JC4, JC5 and JC6 were capable of down-regulating the formation of MDA and lipofuscin. Conclusion: Our results indicated that free radicals play significant roles in lipofuscin formation and cellular aging which can be attenuated by yakuchinone B derivatives.Key Words: Aging, Lipofuscin, Reactive oxygen species (ROS), Yakuchinone B  相似文献   
4.
Gesunde Pflanzen - Humic acid comprises the major part of humic substances and the most important component of soil organic matter (humus) that increases crop yield and quality. This research aimed...  相似文献   
5.
The saturated hydraulic conductivity (\(K_{\text{s}}\)) is one of the important soil hydraulic properties which plays a significant role in developing flow transport models and irrigation and drainage practices. In this research, artificial neural networks approaches, group method of data handling (GMDH) model and a hybrid intelligent model based on combination of GMDH and harmony search (HS) model (GMDH-HS) were developed to estimate \(K_{\text{s}}\) based on 151 field samples collected from the northeast of Iran. Eleven topsoil properties were used as input parameters to estimate \(K_{\text{s}}\). The five quantitative standard statistical performance evaluation measures, i.e., coefficient of efficiency, root-mean-square error, mean square relative error, mean absolute percentage error and relative bias, were employed to evaluate the performance of various developed models. Statistical results indicated that the best performance can be obtained by GMDH-HS in terms of different evaluated criteria during the training and testing datasets for \(K_{\text{s}}\) estimation.  相似文献   
6.
In this research, the factors affecting seed production of six landraces (Sefid-e-Ghom, Germez-e-Azarshahr, Dorcheh-e-Isfahan, Tarom, Germez-e-Kazeroon, Sefid-e-Abarkooh) and a foreign cultivar (Yellow Sweet Spanish as a control) were evaluated in a randomized complete block design experiment with three replications. Results indicated significant differences between genotypes regarding some of the traits. Seed stalks were emerged in Tarom and Yellow Sweet Spanish earlier than other landraces. Flowering of Germez-e-Kazeroon and Tarom were the first and last, respectively. Also, ripening of seed in Germez-e-Kazeroon and Yellow Sweet Spanish was earlier and later than other landraces, respectively. The number of seed stalks/plant and seed yield/ha were increased while increasing in bulb size from 5 to 7 cm. Among the landraces, Sefid-e-Ghom and Germez-e-Azarshahr showed the highest and lowest number of seed stalks/plant, respectively. Sefid-e-Ghom, also, showed the highest seed yield/inflorescence, /plant and/ha. Although the differences were not significant statistically. Relationships between traits showed that seed yield/plant and /ha was a positively correlated with the number of seed stalks/plant. Genotypes were grouped in three clusters using Ward method.  相似文献   
7.
The effects of five different light regimes on growth performance and behaviour of Persian Sturgeon larvae were examined. Larvae were reared under five different photoperiods (24L, 12L:12D, 16L:8D, 8L:16L and 24D), from hatching (25.8 ± 8.1 mg; 12 ± 0.6 mm) to 28 days post‐hatch (dph). Except the last week, there was no significant difference in growth parameters among the experimental groups. Growth performance significantly improved in larvae reared under a continuous light regime. The highest final length (34.5 ± 1.7 mm) was measured in 24L and the lowest one (29.5 ± 0.4 mm) in the constant darkness. Relative to other experimental groups, the continuous darkness had a retarding impact on the yolk sac absorption and swarming behaviour. Among the whole body compositions, the lowest body moisture content was measured in the continuous light group. Persian Sturgeon pre‐larvae and larvae were not completely dependent on light regimes (in 1–21 days), whereas on the basis of measured parameters (total length, wet and dry weight and digestive fullness index) a continuous light regime played a decisive role on growth performance beyond 21 dph.  相似文献   
8.
The possibility of manufacturing rubberwood and kenaf (Hibiscus cannabinus L.) stem medium density fibreboard (MDF) panels at different pressure and resin content were investigated. The effect of mechanisms of interacted independent variables (resin content and pressure) on MDF properties was analyzed. The board performance was evaluated by measuring internal bond (IB) strength, modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swell (TS). The test results were statistically analyzed by using response surface method (RSM) to determine the significant independent variables that influenced MDF properties. A mathematical simulation or response surface models were developed to predict the MDF properties (MOR, MOE, IB, WA and TS). The obtained results showed that MDF density and all interactions between the experimental variables were significant factors that influenced the mechanical properties of MDF. At 8 bar and 14 % resin content, the MDF recorded WA of 83.12 % and TS of 20.2 %. It can be inferred that two parameters (resin content and pressure) had positive effect on physical and mechanical properties of MDF. We concluded that resin content show more significant effects on MDF manufacturing as compared to pressure parameters.  相似文献   
9.
Background:To study the anticancer activity of Plantago major, we assessed the effect of ethanolic, methanolic and acetonic extracts of this plant on HCT-116, SW-480, and HEK-293 cell lines as control. Methods:The cytotoxic activity, biocompatibility, and toxicity were evaluated by MTT assay, hemolysis, and Artemia salina-LD50 (on mice) tests, respectively. The analysis of the extracts was performed by GC-MS analysis. Results:The results showed that all the extracts had the most antiproliferative properties on the HCT-116 cell line. The P. major root extract was more effective than the aerial parts, and IC50 values for ethanolic, methanolic and acetonic root extracts were 405.59, 470.16, and 82.26 µg/mL, respectively on HCT-116 cell line at 72 h. Hemolysis degree of the ethanolic extract of aerial and root parts were approximately 1% at 400 μg/mL.. Using the ethanolic extracts, the Artemia survived every concentration, and no toxicity was observed. One week after the oral administration of different parts of P. major extracts, none of the mice died, even those were administered 2000 mg/kg. The results of GC/MS analysis showed that P. major extracts contain potential anticancer compounds, such as stearic acid (8.61%) in aerial parts of methanolic extract and 1,2- Benzenedicarboxylic acid, mono(2-ethylhexyl)ester (88.07% and 40.63%) in aerial and root parts of acetonic extract of P. major. Conclusions:Our findings suggest that the P. major is a source of potential compounds with antiproliferative properties. Key Words: Gas chromatography-mass spectrometry, HCT-116 cells, Hemolysis, Lethal dose 50  相似文献   
10.
In order to evaluate of using microtubers for conservation of potato germplasm, the main effects of sucrose, mannitol and PEG on percentage of microtuber initiation and formation, size and fresh weight of microtuber were studied. PEG decreased production and weight of microtubers, whereas higher concentrations of sucrose promoted microtuber production, microtuber size as well as microtuber fresh weight. Increasing of sucrose concentrations were improved efficiently in vitro microtuber production without negative side effects. Addition of mannitol to all media was increased microtuberization than media containing PEG. So, alcoholic sugars such as mannitol increased microtuberization, but after 5 weeks, microtuberization in media supplied with sucrose was more than the mannitol. Such studies might help to reduce the cost of production of virus free potato seed from different cultivars.  相似文献   
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