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71.
Osteopontin gene is regarded as a plausible candidate in mammary gland differentiation and development, expressed by variety of cells, tissues, and biological fluids including milk. The current study was performed in two phases. In the first phase, Osteopontin gene polymorphisms were identified and associated with milk composition such as ash, milk fat, SNF, lactose, and protein. In the second phase, milk samples from five healthy mastitis-free Nili Ravi buffaloes were analyzed for expression of Osteopontin gene at transition (day 15), mid (day 90), and end (day 250) stage of their second lactation. Briefly, blood samples were collected from Nili Ravi buffalo to isolate the genomic DNA, specific primers were designed for PCR amplification. The amplified PCR products were sequenced bi-directionally. Six polymorphisms were identified in the coding region and four in the intronic region of the gene. The results showed that SNP g.38329758 T > C causing substitution of valine to alanine (V127A) was associated with high milk protein. For mRNA expression analysis, somatic cells were separated from milk samples for RNA isolation. Analysis of differential gene expression data has permitted us to illustrate the expression pattern of osteopontin gene in lactating buffalo. The Osteopontin gene was found to be transcribed among all three lactation stages, but expression was observed with the highest value (fold change) in peak lactation and remained elevated till the end of lactation. Identified gene marker may be helpful for the prediction of superior animal for selection. The presented study also gave an insight into the genetic screening and lactation biology of riverine buffalo, offering direction for future research in lactating buffalo.  相似文献   
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Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.  相似文献   
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Selenium (Se) is an essential element for human and livestock with antioxidant and anticancer characteristics. Although Se is not an essential element for plants, it has been reported that it can improve plant growth. This experiment was conducted at the Isfahan University of Technology in winter 2010. The experiment was factorial based on a completely randomized design (CRD) with four replications. Se was added to nutrient solution in four concentrations 2, 4, and 6 mg/L sodium selenite (Na2SeO3). Root volume, fresh and dry weights of shoots and roots, number and weight of fruits, chlorophyll content, and photosynthesis traits [photosynthesis rate, stomata internal carbon dioxide (CO2) concentration, stomata conductance] were measured. Results showed that Se increased root dry weight. Fresh and dry weights of shoot increased in the 2 mg/L Se treatment and decreased at the higher level of Se. Chlorophyll content and photosynthesis rate were not affected by Se. Stomata internal CO2 concentration and stomata conductance decreased by Se addition. Overall, Se at 2 mg/L application rate was effective in some physiological characteristics of cucumber.  相似文献   
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Pomegranate (Punica granatum L.) is one of the oldest known edible fruits. It is native to Iran and spread from Iran to other areas. In this study amplified fragment length polymorphism (AFLP) was used to detect intra- and inter-population genetic diversity of pomegranate. A group of 67 accessions belonged to 4 populations from Iran was studied using eight primer combinations. A total of 221 scorable bands were amplified, of which, 118 (54.13%) were polymorphic. Resolving power (Rp) ranged from 5.70 to 9.21, and the average of polymorphism information content (PIC) per primer pair was 0.40. According to Nei's gene diversity and allelic statistics, Isfahan population had a highest genetic diversity (H = 0.3646, I = 0.5327, Ne = 1.6467). Coefficient of gene differentiation between populations (GST) was 0.124, indicated that mainly proportion of genetic variation (87.6%), was within populations and the remaining (12.4%) of the variation was among populations that, also supported by analysis of molecular variance (AMOVA). The gene flow (Nm) varied from 0.969 to 10.404 between pair-wise populations and was 3.504 among all of the populations. The Jaccard similarity coefficient between individuals ranged from 0.26 to 0.88. The UPGMA dendrogram clustered all 67 accessions into 6 groups. In some cases accessions from same region were grouped together but in most cases, there was gene exchange. To study the genetic relationships among populations, a principal coordinate analysis (PCoA) based on Nei's genetic distances was performed. Results of this study showed that AFLP marker can be a useful tool for investigating the genetic diversity of pomegranate genotypes.  相似文献   
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Rodents are sources of many zoonotic pathogens that are of public health concern. This study investigated bacterial pathogens and assessed their antimicrobial resistance (AMR) patterns in commensal rodents in Qatar. A total of 148 rodents were captured between August 2019 and February 2020, and blood, ectoparasites, and visceral samples were collected. Gram-negative bacteria were isolated from the intestines, and blood plasma samples were used to detect antibodies against Brucella spp., Chlamydophila abortus, and Coxiella burnetii. PCR assays were performed to detect C. burnetii, Leptospira spp., Rickettsia spp., and Yersinia pestis in rodent tissues and ectoparasite samples. Antimicrobial resistance by the isolated intestinal bacteria was performed using an automated VITEK analyzer. A total of 13 bacterial species were isolated from the intestine samples, namely Acinetobacter baumannii, Aeromonas salmonicida, Citrobacter freundii, Citrobacter koseri, Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Hafnia alvei, Klebsiella pneumoniae, Providencia stuartii, Proteus mirabilis, Pseudomonas aeruginosa, and Salmonella enterica. The majority of them were E. coli (54.63%), followed by P. mirabilis (17.59%) and K. pneumoniae (8.33%). Most of the pathogens were isolated from rodents obtained from livestock farms (50.46%), followed by agricultural farms (26.61%) and other sources (22.94%). No antibodies (0/148) were detected against Brucella spp., C. abortus, or C. burnetii. In addition, 31.58% (6/19) of the flea pools and one (1/1) mite pool was positive for Rickettsia spp., and no sample was positive for C. burnetii, Leptospira spp., and Y. pestis by PCR. A total of 43 (38%) bacterial isolates were identified as multidrug resistant (MDR), whereas A. salmonicida (n?=?1) did not show resistance to any tested antimicrobials. Over 50% of bacterial MDR isolates were resistant to ampicillin, cefalotin, doxycycline, nitrofurantoin, and tetracycline. The presence of MDR pathogens was not correlated with rodent species or the location of rodent trapping. Seven (11.86%) E. coli and 2 (22.2%) K. pneumoniae were extended-spectrum beta-lactamases (ESBL) producers. These findings suggest that rodents can be a source of opportunistic bacteria for human and animal transmission in Qatar. Further studies are needed for the molecular characterization of the identified bacteria in this study.

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77.
Paddy and Water Environment - Plant Available Water is the main concept for describing the existing water content in a soil profile. Along with this concept, Integral Energy shows the energy...  相似文献   
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Precision Agriculture - Leaf area index (LAI) is a key parameter for the calculation of crop biophysical and biochemical processes. Therefore, the accurate estimates of LAI has been always of great...  相似文献   
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