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1.
A physical map of the 1-gigabase bread wheat chromosome 3B   总被引:2,自引:0,他引:2  
As the staple food for 35% of the world's population, wheat is one of the most important crop species. To date, sequence-based tools to accelerate wheat improvement are lacking. As part of the international effort to sequence the 17-billion-base-pair hexaploid bread wheat genome (2n = 6x = 42 chromosomes), we constructed a bacterial artificial chromosome (BAC)-based integrated physical map of the largest chromosome, 3B, that alone is 995 megabases. A chromosome-specific BAC library was used to assemble 82% of the chromosome into 1036 contigs that were anchored with 1443 molecular markers, providing a major resource for genetic and genomic studies. This physical map establishes a template for the remaining wheat chromosomes and demonstrates the feasibility of constructing physical maps in large, complex, polyploid genomes with a chromosome-based approach.  相似文献   
2.
The moisture transport expressed with wicking is one of the most important aspects in clothing science and strongly effects on the quality of clothes. Wicking is a spontaneous transport of liquid driven into a porous system by capillary forces. Furthermore, the packing density has a direct relation with the yarn structure. At the present work, the effects of yarn count and twist factor on the wicking height and packing density of lyocell ring-spun yarns was investigated. Achieving the objectives of this research, an image processing method was developed to determine the packing density of samples. Experimental results were also used to develop a regression model to predict the wicking height based on the packing density, yarn count, twist factor and rising time. The results demonstrated that the correlation coefficient between the predicted and measured wicking height was 0.98 indicating the capability of the presented model to predict the wicking height of lyocell ring-spun yarns.  相似文献   
3.
Background:Methadone therapy is a major protocol in opioid addiction cases in many health care systems. Population-based studies have shown that in addicted people, the genetic profile affects their response to methadone therapy. Therefore, this study designed to examine the frequency of two SNPs of the CYP2B6 gene (rs3745274 and rs3211371) in addicted cases in two methadone-responders and methadone non-responders groups. Methods:A total of 199 opioid-addicted individuals and 117 unaffected control subjects were genotyped for rs3745274 and rs3211371 polymorphisms of the CYP2B6 gene using the tetra-primer ARMS-PCR. Results:Results of this study revealed the significant association of rs3745274 GG (p < 0.001; OR = 0.027; 95% CI = 0.14-0.49) and GT (p < 0.001; OR = 4.04; 95% CI = 2.26-7.21) genotypes with the risk of addiction in methadone-responders. Also, a significant association between rs3745274 GG (p < 0.001; OR = 0.28; 95% CI = 0.15-0.51) and GT (p < 0.001; OR = 5.1; 95% CI = 2.8-5.28) genotypes and addiction relapse was found in methadone non-responders. Conclusion:Based on our findings, we can conclude that rs3745274 variant of CYP2B6 gene could serve as a potential biomarker, to evaluate the prognosis of addicted people fate under treatment with methadone. Key Words: Addiction, Biomarker, Methadone, Single-nucleotide polymorphism  相似文献   
4.
Normalized difference vegetation index (NDVI), which is a measure of leaf greenness (chlorophyll content), is considered to be correlated with crop productivity. This study was conducted to examine genotypic variations for NDVI at different growth stages and its relationship to yield in winter wheat under terminal heat stress. Thirty winter wheat genotypes were evaluated at two locations in 2009–2010 and 2010–2011 in Uzbekistan. The NDVI was recorded at booting, heading, milk and dough stages. The wheat genotypes differed significantly for NDVI at each stage. Grain yield ranged from 3.9 to 6.1 t/ha. Wheat genotypes differed in per cent decline in NDVI from booting to dough stage. However, several high‐yielding genotypes maintained higher NDVI than low‐yielding genotypes when heat stress was evident. The findings suggest change in NDVI during heat stress could be a measure of tolerance. The positive correlation of NDVI with grain yield suggests that it could be used as an indirect selection criterion for identifying physiologically superior, high‐yielding wheat lines under terminal heat stress.  相似文献   
5.
Wheat is the most important cereal in Central Asia (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) and the Caucasus (Armenia, Azerbaijan and Georgia). Stripe rust, caused by Puccinia striiformis f. sp. tritici is considered the most important disease of wheat in Central Asia and the Caucasus (CAC). Although stripe rust has been present in the region for a long time, it has become a serious constraint to wheat production in the past 10 years. This is reflected by the occurrence of five epidemics of stripe rust in the CAC region since 1999, the most recent in 2010. Several wheat varieties occupying substantial areas are either susceptible to stripe rust or possess a low level of resistance. Information on the stripe rust pathogen in terms of prevalent races and epidemiology is not readily available. Furthermore, there is an insufficient understanding of effective stripe rust resistance genes in the region, and little is known about the resistance genes present in the commercial varieties and advanced breeding lines. The deployment of resistant varieties is further complicated by putative changes in virulence in the pathogen population in different parts of the CAC. Twenty four out of 49 improved wheat lines received through international nurseries or other exchange programs showed high levels of resistance to stripe rust to local pathogen populations in 2009. Fifteen of the 24 stripe rust resistant lines also possessed resistance to powdery mildew. It is anticipated that this germplasm will play an important role in developing stripe rust resistant wheat varieties either through direct adoption or using them as parents in breeding programs.  相似文献   
6.
Trend analysis of reference evapotranspiration in the western half of Iran   总被引:6,自引:0,他引:6  
Reference evapotranspiration (ETo) is an important element of the hydrological cycle, and changes in ETo are of great significance for agricultural water use planning, irrigation system design and management. In this study, annual, seasonal and monthly trends in the Penman-Monteith ETo at 20 meteorological stations during 1966-2005 in the western half of Iran were examined using the Mann-Kendall test, the Sen's slope estimator and the linear regression. Annual analysis of the ETo series indicated a positive trend in 70% of the stations according to the Mann-Kendall test and the Sen's slope estimator and in 75% of the stations according to the linear regression. The magnitude of significant positive trends in annual ETo varied from (+)11.28 to (+)2.30 mm/year. On the seasonal scale, stronger increasing trends were identified in ETo data in winter and summer compared with those in autumn and spring. Meanwhile, the highest numbers of stations with significant trends were found in the monthly ETo series in February, while the lowest numbers of stations with significant trends were observed in November. Analysis of the impact of climatic variables on the significant increasing trend in ETo showed that the increasing trend was mainly caused by a significant increase in air temperature during the study period.  相似文献   
7.
High grain yield and resistance to stripe (yellow) rust are the most important traits for successful adoption of winter wheat varieties in Central and West Asia. This study was conducted to determine the stripe rust response and agronomic performance of a set of breeding lines recently developed by the International Winter Wheat Improvement Program (IWWIP). Replicated field studies were conducted in 2010 and 2011 using 38 experimental lines, one regional check (Konya) and one local check. Stripe rust scores were recorded at Karshi, Uzbekistan, and Karaj and Mashhad, Iran, in 2010. Grain yield was recorded at two sites each in Uzbekistan (Karshi and Kibray) and Iran (Karaj and Mashhad) and one site in Turkey (Eskisehir). The test lines showed variation for stripe rust severity, grain yield, 1,000-kernel weight, days to heading and plant height. Several stripe rust resistant genotypes were either higher yielding or equal to the local checks at different sites. Based on stripe rust resistance and yield performance in 2010, a set of 16 genotypes was selected and evaluated in 2011. All 16 were resistant at Almaty, Kazakhstan, and Dushanbe, Tajikistan, in 2011, whereas 9 of the 16 were resistant at Terter, Azerbaijan. The genotypes ‘TCI-02-138, ‘Solh’, ‘CMSS97M00541S’, ‘TCI -2-88(A)’ and ‘TCI-02-88(C)’ were consistently resistant to stripe across all sites in both years. Several lines showed high grain yields and superior agronomic performance across four sites in Uzbekistan and one site in Tajikistan. One genotype has been released in Uzbekistan and another in Tajikistan.  相似文献   
8.
Sera from patients with ocular and visceral manifestations of toxocariasis were tested by precipitin absorption (PAT), counter-immunoelectrophoresis (CIEP), indirect fluorescent antibody (IFAT) and ELISA. The ocular cases revealed a percentage of positivity of 36% by PAT, 0% by CIEP, 32% and 28% by IFAT with embryonated egg (EE) and frozen section antigens (FS) respectively and 40% by ELISA. The visceral cases revealed 44% positively by PAT, 24% by CIEP 52% and 48% by IFAT with EE and FS respectively and 52% by ELISA. Statistical evaluation was done to interpret the results.  相似文献   
9.
The halophyte Salicornia was recently introduced as a fresh vegetable crop that thrives in extreme salt conditions. Two annual Salicornia and two perennial Sarcocornia ecotypes were investigated for yield production and nutritional value in response to different seawater concentrations in the irrigation solution. A harvest schedule based on a three-week cycle gave better productivity than a two-week or a four-week cycle. Total yield declined with increasing percentage of seawater above 50% in the irrigation water, however annual plants had always ca 2–3-fold higher fresh biomass in comparison to their perennial counterparts. Increased percentages of seawater in the irrigation solution had the following effects on ion concentrations in the shoots: no change in Ca2+ and Mg2+, a slight increase in K+, and marked elevations in Na+ and Cl. Importantly, total polyphenol, β-carotene and ureides, all known for their antioxidant capacities, rose with increasing seawater percentage, findings that indicated improved nutritional values for Salicornia and Sarcocornia irrigated with high concentrations of seawater. Impressively, both the annual Salicornia and the perennial Sarcocornia ecotypes exhibited high total shoot lipid contents of up to 2.41 and 2.06 mg g−1 fresh weight, respectively, which included an omega-3 fraction of 47.6 and 41.2% of the total fatty acid content. Moreover, the high fatty acid content of the annual Salicornia ecotype was not significantly affected by increasing seawater concentrations. In this study, we thus demonstrated the feasibility of cultivating Salicornia and Sarcocornia by applying a multiple harvest system and 100% percentages of seawater in the irrigation water generating economic yields with high nutritional value. The findings also showed that Salicornia and Sarcocornia leafy vegetables may attract additional interest as an alternative source of omega-3 polyunsaturated fatty acids for human consumption, even when the crop irrigated solely with seawater.  相似文献   
10.
Background: Infections due to Pseudomonas aeruginosa are among the leading causes of morbidity and mortality in patients who suffer from impaired immune responses and chronic diseases such as cystic fibrosis. At present, aggressive antibiotic therapy is the only choice for management of P. aeruginosa infections, but emergence of highly resistant strains necessitated the development of novel alternative therapeutics including an effective vaccine. Several P. aeruginosa antigens have been tested for vaccine development, including lipopolysaccharide alone, polysaccharides alginate, extracellular proteins, exotoxin A (exo A) and killed whole cell. However, none of them are currently available clinically. Methods: In this research, recombinant exoA-flagellin (fliC) fusion protein as a cocktail antigen was expressed and purified and its antigenic characteristics were evaluated. Results: Expression of recombinant fusion protein by E. coli using pET22b vector resulted in production of exoA-fliC fusion protein in high concentration. Based on Western-blotting results, recombinant fusion protein showed a good antigenic interaction with sera from patients with various P. aeruginosa infections. Conclusion: These results suggested that recombinant exoA-fliC fusion protein can be produced in the laboratory, and tested as a candidate vaccine in P. aeruginosa infections. Key Words: Pseudomonas aeruginosa, Exotoxin A (exoA), Flagellin (fliC), Vaccines  相似文献   
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