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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: VETERINARY RESEARCH FORUM
- نوع مقاله: Journal Article
- کلمات کلیدی: Apoptosis,Leptin,buffalo,Oocyte,Trichostatin A
- چکیده:
- چکیده انگلیسی: Leptin, the 16-kDa product of the obese (ob) gene, primarily secreted from adipose tissue, has been implicated to play an important role in the regulation of food intake and energy expenditure. This study investigated protective effect of leptin on trichostatin A-induced apoptotic on in vitro maturation ratio of buffalo oocytes. Ovaries were collected from abattoir and were transported immediately to the laboratory by a thermos flask containing sterile normal saline with antibiotics. Oocytes were aspirated from 2 to 8 mm visible follicles. Oocytes were placed in a culture plate and then incubated at 38.5 ˚C with 5% CO2 in air for 24 hr. The maturation of oocytes was evaluated under a stereomicroscope. The FITC-Annexin V and propidium iodide staining method was used to detect oocyte apoptosis. In leptin treated groups with 0, 10, 50 and 100 ng mL-1 and groups that apoptosis was induced, the percentage of oocytes maturation was 77.03, 86.12, 85.08, and 79.89% and 59.96, 56.93 and 51.98, respectively, while the percentage of apoptosis was 8.83, 7.90, 8.58, and 9.39%, and 10.37, 11.57 and 12.03, respectively. Our findings showed that addition of 10 and 50 ng mL-1 leptin to IVM medium of buffalo oocytes could increase oocyte nuclear maturation, and could decrease oocyte apoptosis when trichostatin A added for inducing apoptosis.
- انتشار مقاله: 09-03-1395
- نویسندگان: Hamid Reza Shafiei Sheykhani,Rooz Ali Batavani,Gholam Reza Najafi
- مشاهده
- جایگاه : پژوهشی
- مجله: Teaching English Language
- نوع مقاله: Journal Article
- کلمات کلیدی: tense,Missing Surface Inflection Hypothesis,The Representational Deficit Hypothesis,Full Access/ Full Transfer,Modulated structure building hypothesis,Reassembling,Passivization
- چکیده: شکل زمان و مجهول جمله
- چکیده انگلیسی: The issue of cross-linguistic influence in non-primary language learning has long been an important topic. Studies conducted in this area suggest that a form of L1 or L2 transfer is evident in the language produced by third language learners (Cenoz 2001; Leung 2003; White 2003, among many others). On the nature of this transfer; however, there seems to be no consensus. Whether the acquisition of syntactic structures is a matter of mere parameter setting from a minus value in one language to a plus value in another or a rather painstaking process of reassembling the relevant features from the way they are conditioned and realized in the L1 to that of the L2 or L3 is not yet revealed. While, Hawkins (2003) supports a "Representational Deficit Hypothesis" (RDH) whereby interlanguage grammars are confined to L1 feature values and hence any problem in L2 or L3 initial state is attributed to problems in resetting syntactic features of L1, Lardier (1999, 2000, 2003) argues for a Missing Surface Tnflection Hypothesis (MSTH) in mapping lexical entries onto overt phonological forms. Still there is a third argument which claims that the entire L1 grammar (in the sense of all abstract properties) constitute the initial state in L2 acquisition. Based on this stance, Schwartz & Sprouse (1994, 1996) argue that changes to the initial grammar can take place to the effect that the L2 learners are not confined to representations based on L1 steady state. Finally, Hawkins proposes a moderate modulated structure building Hypothesis (MSBH) which claims for an incremental leaning mechanism for L2 and L3. Inspired by the given issue, the present study attempts to see what effects the interaction of Kurdish and Persian have on Kurdish EFL students' acquisition of syntactic and morphological properties of tense and passive structures in English. To this end, 120 Persian monolingual and Kurdish-Persian bilingual EFL Learners took part in this study. They were assigned to three proficiency bands (after taking a general proficiency test, OPT) and received a grammaticality Judgment and a contextualized functional production tasks. The results showed no significant difference between the performance of monolinguals and bilinguals at each level of proficiency beyond the initial state. Nonetheless, significant differences were found across the levels of proficiency. The findings, interpreted in terms of the viewpoints of the current generative models of L2A, revealed a dominant role for L1 settings in L3 interlanguage grammar especially at the initial state and were more in line with the claims of MSBH.
- انتشار مقاله: 11-09-1385
- نویسندگان: Reza Khani,Manijeh Youhanaee,Hossein Barati
- مشاهده
- جایگاه : پژوهشی
- مجله: Quarterly Journal of Applied Chemical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Ionic Liquid,Proton Exchange Membrane,Direct Methanol Fuel Cell,Hybrid membrane,Silicon containing membrane
- چکیده:
- چکیده انگلیسی: In this paper, the silicon-containing sulfonated polystyrene/acrylate–ionic liquid (Si-SPS/A–IL)
hybrid membranes was prepared to obtain the proton exchange membrane (PEM) materials with
high methanol barrier and good selectivity. The Si-SPS/A–IL hybrid membranes characterized as
the function of IL to evaluate their potential as PEMs in direct methanol fuel cells (DMFCs).Four
different Hybrid material with different properties have been synthesized and named from I to
IV.The potential of the membranes in direct methanol fuel cells (DMFCs) is characterized
preliminarily by studying their thermal stability, ion-exchange capacity, water uptake, methanol
diffusion coefficient, proton conductivity and selectivity (proton conductivity/methanol diffusion
coefficient). All the hybrid membranes exhibit good thermal stability and reasonable water uptake.
IV and V membranes have a low methanol diffusion coefficient, while II and III membrane have
good proton conductivity. In addition, the selectivity values of hybrid membranes increase with
increasing IL content and V membrane shows the best selectivity (1.14×105Ss cm−3). These results
suggest that the Si-SPS/A–IL hybrid membranes are possible candidate materials for PEMs in
DMFC applications.
- انتشار مقاله: 14-03-1397
- نویسندگان: Mohammad Galehassadi,Alireza Khani
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Biofertilizer,Fertilizer,Phosphate,Phosphatase,phosphate rock,phosphatesolubilizing microorganism
- چکیده:
- چکیده انگلیسی: Phosphorus (P) is one of the most vital elements for all living organisms which acts as a
constituent of essential biomolecules such as nucleic acids, phospholipids, and phosphosugars,
and as a major contributor to almost all metabolic reactions including photosynthesis,
respiration, and energy delivery. It is one of the most needed nutrients for plant growth and
development. Despite high levels of P in the soil, plants absorb it only in the soluble inorganic
form of free phosphate ion (Pi) which is scarce in soil. Therefore, there has been a large demand
for Pi fertilizers to secure crop yields, yet its deposition in soil and gradual run-off into water
reservoirs lead to chains of events that cause irreversible damages to ecosystems. Researches,
including genome-wide data analyses, have revealed interesting molecular aspects of plant
adaptive strategies to deal with low Pi concentrations in soil. These include the higher
expression of acid phosphatases and Pi transporters as well as the secretion of organic acids in
the rhizosphere that maintain cellular Pi homeostasis in order to keep metabolic reactions
running. Describing the cycle of Pi exchange between physical and biological worlds, the extent
to which current agricultural practices are disturbing the cycle, the necessity of introducing lessdestructive
methods of providing Pi, and alternative measures and solutions for sustainable
agriculture will be discussed in this review.- انتشار مقاله: 13-09-1392
- نویسندگان: Mohammad Ali Malboobi,Katayoun Zamani,Tahmineh Lohrasebi,Mohammad Reza Sarikhani,Ali Samaian,Mohammad Sadegh Sabet
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Biofertilizer,Fertilizer,Phosphate,Phosphatase,phosphate rock,phosphatesolubilizing microorganism
- چکیده:
- چکیده انگلیسی: Phosphorus (P) is one of the most vital elements for all living organisms which acts as a
constituent of essential biomolecules such as nucleic acids, phospholipids, and phosphosugars,
and as a major contributor to almost all metabolic reactions including photosynthesis,
respiration, and energy delivery. It is one of the most needed nutrients for plant growth and
development. Despite high levels of P in the soil, plants absorb it only in the soluble inorganic
form of free phosphate ion (Pi) which is scarce in soil. Therefore, there has been a large demand
for Pi fertilizers to secure crop yields, yet its deposition in soil and gradual run-off into water
reservoirs lead to chains of events that cause irreversible damages to ecosystems. Researches,
including genome-wide data analyses, have revealed interesting molecular aspects of plant
adaptive strategies to deal with low Pi concentrations in soil. These include the higher
expression of acid phosphatases and Pi transporters as well as the secretion of organic acids in
the rhizosphere that maintain cellular Pi homeostasis in order to keep metabolic reactions
running. Describing the cycle of Pi exchange between physical and biological worlds, the extent
to which current agricultural practices are disturbing the cycle, the necessity of introducing lessdestructive
methods of providing Pi, and alternative measures and solutions for sustainable
agriculture will be discussed in this review.- انتشار مقاله: 13-09-1392
- نویسندگان: Mohammad Ali Malboobi,Katayoun Zamani,Tahmineh Lohrasebi,Mohammad Reza Sarikhani,Ali Samaian,Mohammad Sadegh Sabet
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Structural Engineering and Geotechnics
- نوع مقاله: Journal Article
- کلمات کلیدی: Strength,Self-Compacting Concrete,Genetic Algorithm,neural networks,Slump
- چکیده:
- چکیده انگلیسی:
Compressive strength and concrete slump are the most important required parameters for design, depending on many factors such as concrete mix design, concrete material, experimental cases, tester skills, experimental errors etc. Since many of these factors are unknown, and no specific and relatively accurate formulation can be found for strength and slump, therefore, the concrete properties can be improved to an acceptable level using the neural networks and genetic algorithm. In this research, having results of experimental specimens including soil classification parameters, water to cement ratio, cement content, super-lubricant content, compressive strength, and slump flow, using the MATLAB software, the perceptron neural network training, general regression neural network, and radial base function neural network are considered, and then, with regard to coefficient of determination (R2) criteria and mean absolute error, the above network- انتشار مقاله: 25-01-1396
- نویسندگان: Reza Jelokhani Niaraki,Reza Farokhzad
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of the Iranian Chemical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Electrodeposition,Preconcentration,lead,Palladium,Microwave digestion
- چکیده:
- چکیده انگلیسی: In this work a rapid and selective procedure for separation and preconcentration of lead
(Pb2+) before determination by electrothermal atomic absorption spectrometry (ETAAS) was
developed. The procedure is based on the electrodeposition on a graphite probe modified with
palladium. The lead was deposited from acetate buffer solution at pH 5.5. Various parameters,
such as pH of solutions, deposition potential, buffer concentration, stirrer speed, time of
deposition and temperature program, were optimized. After optimization of the conditions,
detection limit 17 ng L–1 by 3 σ, and enrichment factor 61 were achieved for 2 min
electrodeposition time and improved as deposition time was increased. Linearity of calibration
was kept between 0.05-0.50 μg L–1 with a correlation coefficient of 0.9979 and suitable
precision, R.S.D. % = 5.1 (n = 8). Samples were digested completely in a closed microwave
digestion system using only perchloric acid, and interference owing to various cations was also
investigated. The procedure was successfully applied to determine the presence of lead in rice,
radish, okra, onion and water samples.- انتشار مقاله: 15-02-1390
- نویسندگان: Ahmad Rouhollahi,Reza Moradkhani,Hamid Shirkhanloo,Jahan B. Ghasemi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Residual stress,Shot Peening,Steel,Fatigue Test
- چکیده:
- چکیده انگلیسی: In shot peening process the work piece surface is struck by a large number of balls and compressive residual stress is generated on the surface. So, mechanical properties such as fatigue strength, stress corrosion resistance, smooth shape and ... will improve. In this paper, the balls with a speed of 100 to 200 m/s were struck on the steel samples and fatigue strength compared with specimens without shot peening. The results indicated a significant increase in fatigue strength. Also the balls deep changes on the samples were calculated using ANSYS software and the results were compared with the experimental results. Results showed that, if the ball speed is 100 m/s, it leads 25% increase in fatigue strength while the residual stress will increase to 250 MPa. Furthermore, if the ball speed is 200 m/s, fatigue strength and residual stress increase up to 40% and 300 MPa, respectively. It is also concluded that the stress in the balls is twice as the work piece surface residual stress.
- انتشار مقاله: 06-07-1394
- نویسندگان: Mehdi Tajdari,Hamid Reza Baharvandi,Ali Reza Moradkhani
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Patient Safety & Quality Improvement
- نوع مقاله: Journal Article
- کلمات کلیدی: Efficacy,Hospital Performance,Suggestion system
- چکیده:
- چکیده انگلیسی: Introduction: Suggestion system is a cooperative management method, which has been applied in organizations during the recent years. Suggestion system provides an opportunity for the staff, customers, and contractors to submit their ideas and suggestions to the manager to be applied if befitting. In this study, we aimed to evaluate efficacy of the suggestion system in Hashemi Nezhad Hospital of Mashhad University of Medicine Sciences.
Materials and Methods: This descriptive survey was performed in all the staff (n=110) of Hashemi Nezhad Hospital of Mashhad, in 2012. The data collection instrument, which was a self-designed questionnaire including 22 items in three domains of hospital performance, efficiency, and personnel satisfaction, was distributed among the personnel. Validity of the questionnaire was determined by 10 Management experts, and its reliability was confirmed by a pilot study and Cronbach's alpha (α=0.9). The data were analyzed using SPSS Version 16.
Results:The results indicated that suggestion system had a moderate effect on all the three domains (hospital performance [38.51%], efficiency of hospital [37.57%], and personnel satisfaction [32.88%]).
Conclusion: Efficacy of the suggestion system was in an average level. Conducting further studies on problems before the implementation of suggestion system can be effective in promoting efficacy of this system.- انتشار مقاله: 08-09-1393
- نویسندگان: Reza Jafaei Dalooei,Seyed Mohsen Seyedi,Amir Reza Amirkhani,Ali Vafaei Najar
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Medicinal plants and By-product
- نوع مقاله: Journal Article
- کلمات کلیدی: Humic acid,Yield,Biofertilizers,Vermicompost,Leaf nutrients
- چکیده:
- چکیده انگلیسی: It is important to investigate and develop the strategies and methodologies to maintain the sustainability of plant production. A two-year field study was performed to evaluate calendula response to individual form and also mixtures of selected bio organic fertilizers. The effects of co-inoculation of two plant growth promoting rhizobacteria (PGPR), humic acid (HA), vermicompost (VC), and combinations of these bio organics were investigated in two calendula cultivars, Isfahan multi petalled (MP) and single petalled (SP). The experimental design was a factorial randomized complete block with three replicates. Based on the combined analysis of two years, mean flower yield was highest for the MP cultivar treated by VC + PGPR. Flower essential oil was higher in the MP cultivar than the SP cultivar and did not vary with fertilizers. The highest harvest index of flowers obtained from the MP cultivar treated by HA + PGPR. Furthermore, nutrient contents of leaves increased by fertilizers and combined application of bio organics gave the highest values of nitrogen, phosphorus and potassium contents in calendula leaves. The present results indicate that the selected bio organic fertilizers can be used to obtain higher levels of quality and yield in sustainable agricultural practices.
- انتشار مقاله: 13-07-1397
- نویسندگان: Shiva Zaferanchi,Saeid Zehtab Salmasi,Seyed Yahya Salehi-Lisar,Mohammad Reza Sarikhani
- مشاهده