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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Plant Physiology and Breeding
- نوع مقاله: Journal Article
- کلمات کلیدی: Gas exchange,Drought,Water use efficiency,dry weight,Re-watering
- چکیده: تنش خشکی یکی از مهمترین عوامل محدود کننده برای رسیدن به عملکرد بالا به خصوص در مناطق نیمه خشک است. گیاهان برای سازش به شرایط کم آبی دچار یکسری از تغییرات مورفولوژیکی، فیزیولوژیکی، بیوشیمیایی و مولکولی میشوند. هدف از مطالعه حاضر بررسی اثر تنش خشکی بر سرعت فتوسنتز خالص، مقاومت روزنه، راندمان مصرف آب و ماده خشک زیست توده در شش هیبرید ذرت (Zea mays L.) بود. تنش خشکی از طریق عدم مصرف آب در مرحله 4-5 برگی (S1، مرحله رویشی)، مرحله گرده افشانی (S2، مرحله زایشی) و هر دو مرحله (S3، ترکیبی از مراحل رویشی و زایشی) اعمال شد. نتایج نشان داد که تمام صفات در هیبریدها تحت تنش خشکی تغییر یافتند، ولی ارزش آنها، بعد از آبیاری دوباره به مقادیر اولیه نزدیک شد. همچنین، تاثیر تیمار S3 بر تبادلات گازی برگ از شدت بیشتری نسبت به تیمارهای S1 و S2 برخوردار بود. Pn در اثر تحمل خشکی در هیبریدهای SC647 و SC704 با میزان کمتری کاهش یافت. علاوه بر این، SC700، SC704 و SC647 حداکثر ماده خشک زیست توده و ارتفاع بوته را داشتند. اما، کارایی مصرف آب در طول تنش خشکی به خصوص در هیبریدهای SC260 و SC370 کاهش قابل توجهی داشت. از این مطالعه، میتوان نتیجه گرفت که هیبریدهای SC704 و SC647 متحمل و هیبریدهای SC260 و SC370 حداقل تحمل را به تنش خشکی دارند. تنوع مشاهده شده در میان هیبریدهای مورد بررسی حاکی از وجود ذخایر ژنتیکی ارزشمند برای بهبود محصول در ارتباط با تحمل به خشکی است.
- چکیده انگلیسی: The aim of present study was to evaluate the effects of drought stress on net photosynthesis rate (Pn), stomatal resistance, water use efficiency (WUE) and biomass (BM) of six maize (Zea mays L.) hybrids. Drought stress applied by withholding water supply at 4-5 leaf stage (S1, vegetative stage), anthesis (S2, reproductive stage), and dual stress condition (S3, combination of vegetative and reproductive stages). Results showed that all of the traits changed differently among hybrids under water stress but recovered close to initial values after re-watering. S3 affected leaf gas exchange and agronomic traits more severely than S1 and S2 treatments. Pn decreased due to imposed drought but more slowly in hybrids SC647 and SC704. In addition, SC700, SC704 and SC647 had the maximum BM and plant height. But, WUE decreased during the water stress period especially in hybrids SC260 and SC370 in which the decrease was remarkable. It can be concluded that SC704 and SC647 were the most tolerant and SC260 and SC370 were the least tolerant hybrids to water stress. The variation observed amongst the evaluated hybrids suggests the existence of valuable genetic resources for crop improvement in relation to drought tolerance.
- انتشار مقاله: 11-07-1394
- نویسندگان: Maryam Goodarzian-Ghahfarokhi,Cyrus Mansouri-Far,Mohsen Saeidi,Majid Abdoli,Mohammad Esmaeilpour-Jahromi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Applied Biotechnology Reports
- نوع مقاله: Journal Article
- کلمات کلیدی: Vitamin C,Organic fertilizer,Human Heath,Nitrate accumulation,AtNRT 1:1 gene
- چکیده:
- چکیده انگلیسی: Introduction: Nowadays, increasing environmental risks to human health have caused increasing attention to use chemical nitrogen sources efficiently or nitrogen supplying from organic amendments. In this respect, chicken manure seems to be a good alternative to chemical nitrogen fertilizers. The purpose of this experiment is to investigate the role of urea and poultry manure and ecological factors (climate) on the quantity of some chemical compositions of the potato tuber.
Materials and Methods: To study the effects of urea and poultry manure on some potato tuber compositions, the factorial experiment was conducted in 2015-2016 during the growing season in 2 regions; Azna and Khorramabad which is located in Lorestan province in the west of Iran. The factors were 2 different sources of nitrogen supply including urea fertilizer and poultry manure.
Results: Results show that the highest activity of nitrate reductase (NR) in both sites was observed using 10304 kg of poultry manure ha-1. The results also showed that the tuber nitrate content was only affected by the fertilizer source. In both studied places, the highest tuber nitrate was associated with high levels of urea fertilizer. Based on the results, the vitamin C of potato tubers grown by poultry manure were also superior to the relative vitamin C content. According to the results of this experiment, the accumulation of more than 2 times the nitrate in the tubers was obtained from urea fertilizer (244.2 versus 100 ppm).
Conclusions: In order to achieve food security and an efficient and sustainable food chain, chemical fertilizers must be replaced with organic fertilizers. Thus, the belief that the use of organic fertilizers, at any level, would not cause any problem for the health of products is definitely incorrect.- انتشار مقاله: 23-04-1398
- نویسندگان: Mohammad Asefi,Mahmud Khoramivafa,Ahmad Ismaili,Mohsen Saeidi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Rat,Brain,cytochrome C,Streptozotocin,Amyloid plaque,Human chorionic gonadotropin
- چکیده:
- چکیده انگلیسی: Objective(s): Amyloid β plaques, in Alzheimer’s disease, are deposits in different areas of the brain such as prefrontal cortex, molecular layer of the cerebellum, and the hippocampal formation. Amyloid β aggregates lead to the release of cytochrome c and finally neuronal cell death in brain tissue. hCG has critical roles in brain development, neuron differentiation, and function. Therefore, we investigated the effect of hCG on the density of the congophilic Aβ plaque and cytochrome c-ir neurons in the hippocampus, prefrontal cortex, and cerebellum of Streptozotocin (STZ)-treated rats.
Materials and Methods: Alzheimer model in rats (except the control group) was induced by streptozotocin (3 mg/kg, Intracerebroventricularly (ICV)). Experimental group rats received streptozotocin and then different doses of hCG (50, 100, and 200 IU, intraperitoneally) for 3 days. 48 hr after last drug injection and after histological processing, the brain sections were stained by congo red for congophilic amyloid β plaques and cytochrome c in the hippocampus, prefrontal cortex, and cerebellum were immunohistochemically stained.
Results: Density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons was significantly higher in ICV STZ treated rats than controls. Treatment with three doses of hCG significantly decreased the density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons in the rat hippocampus, prefrontal cortex, and cerebellum in ICV STZ-treated rats (P<0.05).
Conclusion: hCG can be useful in AD patients to prevent the congophilic Aβ plaque formation and decrease cytochrome c-immunoreactive neuron density in the brain.- انتشار مقاله: 05-02-1397
- نویسندگان: Emsehgol Nikmahzar,Mehrdad Jahanshahi,Leila Elyasi,Mohsen Saeidi,Fatemeh Babakordi,Gozal Bahlakeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Rat,Brain,cytochrome C,Streptozotocin,Amyloid plaque,Human chorionic gonadotropin
- چکیده:
- چکیده انگلیسی: Objective(s): Amyloid β plaques, in Alzheimer’s disease, are deposits in different areas of the brain such as prefrontal cortex, molecular layer of the cerebellum, and the hippocampal formation. Amyloid β aggregates lead to the release of cytochrome c and finally neuronal cell death in brain tissue. hCG has critical roles in brain development, neuron differentiation, and function. Therefore, we investigated the effect of hCG on the density of the congophilic Aβ plaque and cytochrome c-ir neurons in the hippocampus, prefrontal cortex, and cerebellum of Streptozotocin (STZ)-treated rats.
Materials and Methods: Alzheimer model in rats (except the control group) was induced by streptozotocin (3 mg/kg, Intracerebroventricularly (ICV)). Experimental group rats received streptozotocin and then different doses of hCG (50, 100, and 200 IU, intraperitoneally) for 3 days. 48 hr after last drug injection and after histological processing, the brain sections were stained by congo red for congophilic amyloid β plaques and cytochrome c in the hippocampus, prefrontal cortex, and cerebellum were immunohistochemically stained.
Results: Density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons was significantly higher in ICV STZ treated rats than controls. Treatment with three doses of hCG significantly decreased the density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons in the rat hippocampus, prefrontal cortex, and cerebellum in ICV STZ-treated rats (P<0.05).
Conclusion: hCG can be useful in AD patients to prevent the congophilic Aβ plaque formation and decrease cytochrome c-immunoreactive neuron density in the brain.- انتشار مقاله: 05-02-1397
- نویسندگان: Emsehgol Nikmahzar,Mehrdad Jahanshahi,Leila Elyasi,Mohsen Saeidi,Fatemeh Babakordi,Gozal Bahlakeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Gene expression,Gestational Diabetes Mellitus,Langerhans islets,Offspring
- چکیده:
- چکیده انگلیسی: Objective(s): The link between a hyperglycemic intrauterine environment and the development of diabetes later in life has been observed in offspring exposed to gestational diabetes mellitus (GDM), but the underlying mechanisms for this phenomenon are still not clear. Reduced β-cells mass is a determinant in the development of diabetes (type 1 and type 2 diabetes). Some recent studies have provided evidence that the CDK4-pRB-E2F1 regulatory pathway is involved in β-cells proliferation. Therefore, we postulated that GDM exposure impacts the offspring’s β-cells by disruption in the CDK4-pRB-E2F1 pathway.
Materials and Methods: Adult Wistar rats were randomly allocated in control and diabetic group. The experimental group received 40 mg/kg/body weight of streptozotocin (STZ) on day zero of gestation. After delivery, diabetic offspring of GDM mothers and control dams at the age of 15 week were randomly scarified and pancreases were harvested. Langerhans islets of diabetic and control groups were digested by collagenase digestion technique. After RNA extraction, we investigated the expressions of the kir 6.2 and CDK4-pRB-E2F1 pathway genes by quantitative real-time PCR.
Results: GDM reduced the expression of CDK4-pRB-E2F1 pathway genes in Langerhans islets cells of offspring. CDK4, pRB and E2F1 pathway genes were downregulated in diabetic islets by 51%, 35% and 84%, respectively. Also, the expression of Kir 6.2 was significantly decreased in diabetic islets by 88%.
Conclusion: We suggest that the effect of gestational diabetes on offspring’s β-cells may be primarily caused by the suppression of CDK4-pRB-E2F1 pathway.- انتشار مقاله: 12-11-1395
- نویسندگان: Zahra Nazari,Mohammad Nabiuni,Mohsen Saeidi,Mohammad Jafar Golalipour
- مشاهده
- جایگاه : پژوهشی
- مجله: Environmental Energy and Economic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: risk assessment,Oil storage tanks,FTA,ETBA,Loss causation model
- چکیده:
- چکیده انگلیسی: The purpose of this research was to introduce and describe a model for Fire Quantitative Risk Assessment of in petroleum Storage Tanks. A novel model was designed to determine the risk of a fire occurrence using of Loss Causation and Swiss cheese models. Then, based on FTA, model and its integration with our initial proposed model, the final model was obtained for fire hazard determination in hydrocarbon tanks. The risk level of the hazard was identified using the energy trace and barrier analysis (ETBA). The quantitative fire risk assessment in the tank were carried out in accordance to the International Association of Oil & Gas Producers (IOGP) guideline. Base on the results, 22 risks were identified which 4 of them were unacceptable risks and corrective action was proposed for them. This method is commonly used in conjunction with the safety analysis of the system. This technique was the final part of this research.
- انتشار مقاله: 04-01-1398
- نویسندگان: Mohsen Saeidi Keshavarz,Fatemeh Razavian,Soroush Namjoufar,Mohammad Ali Zahed
- مشاهده