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51.
Employing locally adapted plants together with irrigation scheduling based on developmental stage in semi-arid and arid regions may provide an opportunity to optimize irrigation efficiency, and water savings in regions where water resources are limited. To investigate this water saving potential, the final seed yield and quality of two local plant species were investigated under water deficit conditions over two growing seasons (2003, 2004) in the northeast of Iran. In this study, black cumin (Nigella sativa L.) which is used locally as an anti-microbial and isabgol (Plantago ovata Forsk.) which is used as an anti-diabetic plant were exposed to four different irrigation regimes. Weekly irrigation was the control, and the three treatments based on developmental stage for both species were termination of irrigation at blooming (folded flowers), flowering, and seed formation. Isabgol seed yield was lower for all of the water deficit treatments compared to control, but black cumin showed tolerance to water deficit except when irrigation was terminated at seed formation. The lowest seed yield was obtained when irrigation was stopped at the blooming stage, and the number of seeds per plant was the main yield component affected. One thousand seed weight for both species was relatively stable across all irrigation treatments, and higher seed yield was consistent with higher straw yield and plant height. Our results did not show any reduction in oil concentration for black cumin or mucilage percentage for isabgol across all water deficit treatments.  相似文献   
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Clinical findings, geographic locations, laboratory diagnoses, and culture isolation of Neorickettsia spp. in Potomac horse fever (PHF) cases diagnosed in Ontario between 2015 and 2019 are described. Forty-six confirmed PHF cases occurred from late June to early September. Of 41 horses admitted to the Ontario Veterinary College, 28 (68%) survived and 13 (32%) were euthanized due to poor prognosis or financial constraints. Most cases were in southern Ontario along the Canada-USA border. Blood and fecal samples from 43 suspect PHF cases were submitted to 2 laboratories for polymerase chain reaction (PCR) testing for Neorickettsia risticii. Agreement between both laboratories for detection of N. risticii DNA was excellent for feces [κ = 0.932, 95% confidence interval (CI): 0.80 to 1], and fair for blood samples (κ = 0.494, 95% CI: 0.13 to 0.85). Neorickettia spp. were isolated from 16 of 41 (39%) blood samples. DNA analysis confirmed 14 isolates were N. risticii and 2 were N. findlayensis, a novel species of Neorickettsia recently demonstrated to cause PHF.  相似文献   
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A study was conducted to select the best alternative for the development of construction panels as well as investment in its manufacturing in Iran.Three alternatives are considered,cement-bonded wood composite product,substituted products(such as concrete panel) sandwich panel and a mixture of them.We apply the analytic network process(ANP) to achieve this goal.A hierarchy is designed to prioritize benefits,opportunities,costs and risks(BOCR) by using the Analytic Hierarchy Process(AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy is also created and prioritized by applying the Analytic Network Process(ANP).A total of four major control criteria in the system are prioritized where each one controls a decision network evaluated using ANP.The final synthesis of the system shows cement-bonded wood composite product is the best choice among three potential alternatives for the investment and development.  相似文献   
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Depending on plant genotype–environment interactions, cell signal transduction, and thereby gene expression, disruptive or promotive effects on grapevine physiology, metabolism, and, consequently, fruit quality and yield may occur. This review article aims to evaluate the effects of temperature and light stress on grapevine signaling and metabolic pathways to provide insights into breeding/engineering strategies for designing grapevines with improved quality, yield and tolerance. The modifications of signaling and metabolic pathways are discussed to assist geneticists with designing tolerant grape cultivars with high capacity of producing bioactive compounds and, thereby health-promoting effects in grapevines and humans.  相似文献   
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In this study we determined some morpho-physiological characteristics of mung bean plants under various irrigation regimes (irrigation after 50, 100, 150 and 200 mm evaporation from pan class A) and mycorrhizal fungi inoculation (Glomus mosseae, Glomus intraradices). The highest and lowest seed yield was obtained from plants irrigated after 50 and 200 mm evaporation from pan, respectively. Root dry weight, root volume, leaf phosphorus and relative water content were decreased in plants under water deficit stress. Whereas, under various level of severe water deficit the proline content, total soluble carbohydrates and leaf nitrogen were increased. Mycorrhizal colonization was observed to be higher in well-watered plants rather than in stressed plants. Furthermore, the mycorrhizal plants produced a higher seed yield (161 g/m2), leaf phosphorus, leaf nitrogen, chlorophyll index, proline, total soluble carbohydrates content, relative water content, root length, root volume, root dry weight and root/shoot weight ratio as compared with non-mycorrhizal plants.  相似文献   
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Background:There is limited information on the 3D prediction and modeling of the colistin resistance-associated proteins PmrA/B TCS in Acinetobacter baumannii. We aimed to evaluate the stereochemical structure and domain characterization of PmrA/B in an A. baumannii isolate resistant to high-level colistin, using bioinformatics tools. Methods:The species of the isolate and its susceptibility to colistin were confirmed by PCR-sequencing and MIC assay, respectively. For 3D prediction of the PmrA/B, we used 16 template models with the highest quality (e-value <1 × 10−50). Results:Prediction of the PmrA structure revealed a monomeric non-redundant protein consisting of 28 α-helices and 22 β-sheets. The PmrA DNA-binding motif displayed three antiparallel α-helices, followed by three β-sheets, and was bond to the major groove of DNA by intermolecular van der Waals bonds through amino acids Lys, Asp, His, and Arg, respectively. Superimposition of the deduced PmrA 3D structure with the closely related PmrA protein model (GenBank no. WP_071210493.1) revealed no distortion in conformation, due to Glu→Lys substitution at position 218. Similarly, the PmrB protein structure displayed 24 α-helices and 13 β-sheets. In our case, His251 acted as a phosphate receptor in the HisKA domain. The amino acid substitutions were mainly observed at the putative N-terminus region of the protein. Furthermore, two substitutions (Lys21→Ser and Ser28→Arg) in the transmembrane domain were detected. Conclusion: TheDNA-binding motif of PmrA is highly conserved, though the N-terminal fragment of PmrB showed a high rate of base substitutions. This research provides valuable insights into the mechanism of colistin resistance in A. baumannii. Key Words: Acinetobacter baumannii, Amino acid substitution, Colistin, Mutation  相似文献   
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There are few published reports of equine enterocutaneous fistulae, and they are almost always related to umbilical hernias. Colocutaneous fistula as a result of a penetrating wound has not been reported in horse. In this case report, surgical treatment of a traumatic colocutaneous fistula in an 8-year-old stallion is described. Under inhalation anesthesia, the fistula was removed completely, and the resultant defect on the left ventral colonic wall was closed. The defect of abdominal wall was closed routinely. The horse regained his previous performance, and no surgical complication was observed at 1 year’s follow-up.  相似文献   
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