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11.
Nuclear magnetic resonance ‐based metabolomics was applied to study effects of egg aging on ovarian fluid metabolites in rainbow trout, Oncorhynchus mykiss. The eggs of three females were pooled and then assigned to three plastic vials for 18 days in vitro storage at 4°C. Ovarian fluid samples were taken 0, 6, 12 and 18 days after storage. Three groups of metabolites including amino acids, osmolytes and energy metabolites were found to change during storage period. The glucose levels of ovarian fluid showed significant decreases on days 12 and 18 after storage (< .05). For acetoacetate and acetate, significant increases were observed, respectively, on days 12 and 18 after storage (< .05). The creatine levels of ovarian fluid increased significantly on days 12 and 18 after storage (< .05). Lactate levels in ovarian fluid elevated during storage period (< .05). Glycerol levels showed a significant increase on days 12 and 18 after storage (< .05). The values of osmolytes in ovarian fluid (e.g., betaine, taurine, trimethylamine‐N‐oxide, N,N‐dimethylglycine) showed a decreasing trend on day 12 which continued until the end of storage on day 18 (< .05). Almost all amino acids elevated on days 12 and 18 after storage (< .05). After an apparent elevation in isoleucine levels on days 6 and 12, this amino acid decreased on day 18 after storage (< .05). The osmolytes might act as antioxidant against free‐radicals produced as a result of over‐ripening. Glucose can be used as energy resource for eggs and bacteria during ova storage. Also, change pattern of amino acids indicate hydrolysis of proteins as the time of storage increases.  相似文献   
12.
The aim of this article is to investigate and measure farmers' satisfaction regarding extension services to better understand why farmers do or do not participate in such programs in Iran. Our study sample consisted of 240 farmers selected through simple quota random sampling (160 male and 80 female) from a list of names from the extension organization. Data were gathered through a face-to-face survey of farmers. Structural equation modeling analysis revealed that perceived quality and perceived value significantly predicted farmers' overall satisfaction. Furthermore, farmer satisfaction can predict farmers' loyalty to extension program activities. From a practical point of view, the present study provides a justification for using perceived quality and perceived value in policy and decision making that seeks to encourage farmers to use agricultural extension programs (AEPs).  相似文献   
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One of the most important elements affecting the growth and development of a plant is salinity. Therefore, to evaluate the effect of salinity on some physiological aspect of Strawberry (Fragaria x ananassa Duch.) plants cv. Camarosa, a greenhouse experiment was conducted at Vali-e-Asr University of Rafsanjan in 2009. This study was carried out as Factorial experiment based on RCD design with 4 replications to determine the influence of salinities (0, 30, 60 and 9 mMol.L-1) on proline, soluble sugars content, chlorophyll a (CHLa), chlorophyll b (CHLb), total chlorophyll (TC), Spad and chlorophyll florescence. Results indicated that fresh leaves tissue were used to measure proline, soluble protein and soluble sugars content, CHLa, CHLb, TC. Salinity treatment significantly increased proline content, soluble sugars while chlorophyll a (CHLa), chlorophyll b (CHLb), Spad and chlorophyll florescence significantly decreased. Nine day after NaCl exposure, Fv/Fm and Spad in 60 and 90 mM NaCl were significantly lower than control. It was concluded that this cultivar of strawberry may uses osmoregulation by increasing proline and soluble sugars level in order to tolerate salinity conditions.  相似文献   
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Efficacy of 1?mM humic (HA) and salicylic (SC) acids on SC 260 and SC 705 corn seedlings to alleviate drought stress via polyethylene glycol was studied via hydroponics at Shiraz University, Iran in a factorial, randomized design, with four replicates each. Under stress, SC 260 had higher electrolyte leakage compared to SC 705, and exogenous application of HA combined with SA decreased SC 705 electrolyte leakage. As a general trend, photosynthetic pigment content, relative water content, root and shoot length, mean number and diameter of central and peripheral root metaxylem, and K+ accumulation were higher in SC 705 treated with HA and SA compared to SC 260. Application of HA with SA could be an effective and low cost approach to ensure seedling establishment and plant growth in fields affected by soil drought in the early season, especially for the SC 705 corn hybrid in semi-arid regions.  相似文献   
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A review of publications on “Strawberry” was done by using the Scopus database for the period 1960–2016. A total of 10,400 articles were found in the database and analyzed using a variety of measures. Results show that publication increased exponentially from 1960 to 2016. Multiple authors are collaborating in strawberry research. Acta Horticulturae was the most productive journal. The United States of America was the most productive country. The greatest portion of the research was concerned with medicinal benefits of strawberries to humans. This work will be useful to researchers in identifying trends in strawberry research.  相似文献   
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In 2012, a greenhouse experiment was conducted to investigate the effects of field soil (C0), residual composted municipal waste (CMW), and residual composted sheep manure (SM) on the growth of triticale in pots previously growing oilseed rape in 2011. To each soil group, one of three levels of urea nitrogen (N) fertilizer was added. Results demonstrated that triticale grown in pots previously containing oilseed rape plants containing SM or CMW with 150 kg urea N ha?1 had the highest N content. Plants grown in SM with 150 kg N ha?1 had the greatest seed yield, but yield was not significantly different from plants grown in CMW receiving 150 kg N ha?1. Triticale plants enriched by either SM or CMW had a higher amount of N, copper, zinc, and manganese compared to the field soil control.  相似文献   
19.

Preventive measures should be prioritized for the increased growth of bacterial contamination in aquatic organisms. This study is aimed at molecular investigation of the prevalence of Pseudomonas aeruginosa, antibiotic resistance, and virulence factor encoding genes. After confirmation of P. aeruginosa collected from shrimp samples (in the same size) in Isfahan and Chabahar (Iran) in summer and autumn, antibiotic resistance encoding genes, virulence factor encoding genes, and multi-drug resistance (MDR) patterns were assessed. Bacterial contamination from Isfahan was higher than Chabahar despite having a cooler climate on summer days. Antibiotic resistance to piperacillin in fresh shrimp samples in summer in Isfahan was contrary to its usage as a front-line antibiotic agent. Lowered MDR pattern in frozen shrimp viability of bacteria was related to the varied expression of antibiotic resistance, highlighting the importance of regulations for cold chain in storage, transportation, and distribution of marine samples compared to fresh shrimps. Foodborne pathogens are of clinical and environmental importance. Results of our study indicated a high rate of frequency for P. aeruginosa isolated from marine samples. Maintenance of cold chain has indispensable roles in preservation, and reduction of P. aeruginosa frequency in aquatic organisms.

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20.
We investigated for the first time the occurrence, stability and antibiotic resistance of 593 enterococci in six samples collected from three urban sewage treatment plants (STPs) located in the north, south and west part of Tehran, Iran between October 2004 and September of 2005. Isolates were typed with a biochemical fingerprinting method (the PhPlate system) and tested for their resistance to six antibiotics. The most prevalent species in all three STPs were E. faecium followed by E. hirae and E. faecalis accounting for 93% of the total isolates examined. In all, 317 (55%) isolates were susceptible to all six antibiotics tested and the remaining isolates were resistant to between 1 and 6 antibiotics. Biochemical fingerprinting with PhPlate system showed a high diversity for E. faecalis (D i?=?0.95), E. hirae (D i?=?0.93) and E. faecium (D i?=?0.95) populations with an overall diversity of D i?=?0.97 for the whole enterococcal populations found in all three STPs. Our data indicate a high degree of polyclonality among the enterococci populations of human origin. This study suggest that the municipal wastewaters might be an important source of dissemination of antibiotic-resistant enterococci in Iran.  相似文献   
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