modern research physics

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Dibenzo sulfoxide macrocyclic diamides possess a hydrophilic cavity surrounded by hydrophobic ring, which enable them to diffuse from cell membrane and interfere with different living systems including ion channels. This study evaluated cytotoxicity effects of this compound in a range of different doses on Balb/C mouse via inter peritoneal injection. Results showed that LD50 concentration was at 2500 µg/Kg.bodyweight. Histological evaluation of animals livers after one-week treatment to 1500 µg/Kg of this compound revealed insignificant changes in hepatocyte cords, portal area, sinusoids and cells of coopfer and hepatocytes with respect to control animals. On the other hand, Histological evaluation of animals’ testis indicated significant decrease in weight, seminiferous tubule diameter and volume of testis and also in the cell number of spermatogonia (A and B), primary spermatocytes, spermatides, spermatozoids and sertoli. In this condition of exposure, antioxidative enzyme activities of peripheral blood, liver and testis increased in a dose dependent manner and reached the highest and significant levels at 1500 µg/Kg. However, the increase in oxidative damage biomarkers including malondialdehyde (MDA) and dityrosine were considerable for peripheral blood and testis. Accordingly, the studied compound had toxic effect and could affected testis when the animals were treated with chemical agent subLD50 for one week. The liver didn’t show toxicity effect of this compound even at 1500 µg/Kg exposure for one week. It could be attributed to high metabolism potential and marked antioxidative activities of this tissue.

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This study was carried out in Kalat highlands of Gonabad, Eastern Iran, located in geographical position of 34º 6´ to 34º 16´ N and 58º 25´ to 58º 35´ E with the altitude of 1100 to 2830 m.a.s.l. The mean annual precipitation and temperature are 143.2mm and 17.2ºC, respectively. Species richness, evenness and species diversity, diversity and related models, diversity based on the rank/abundance plots as well as methods of diversity ordering were considered in three elevation zones including low, intermediate and high altitudes and in the four slope aspects. Species richness indices in the intermediate zone were more than those in the low and high altitudes. The intermediate zone showed the highest species diversity as well as the highest evenness among the zones. North aspect showed the highest species richness and lowest species diversity and evenness. The highest diversity and evenness were observed in the south and south and west aspects, respectively. The low altitude zone followed lognormal distribution however intermediate and high altitude zones do not fit any of the models. Species abundance patterns of the north and west aspects followed both lognormal and logarithmic models with a shift from being lognormal to logarithmic model. The intermediate altitude zone and the south aspect had more flattened rank/abundance plot therefore they have been more diverse than the others. The same was observed by using diversity profiles.

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The Ursolic Acid and Oleanolic Acid presented in apple peels have a potential antioxidant acivity. Antiprolifertive acivity of the triterpenoids against human liver cancer cells, breast cancer cells and colon cancer ells is evaluated. In this study, we have used Ursolic Acid and Oleanolic Acid which are predominant isolated triterpenoids of the apple peels.. The purpose of this study is to determine antimutation and anticarcinogen effect of Ursolic Acid and Oleanolic Acid against Sodium Azide mutagen substance by the use of Microsome and Ames test.
These substances were white powder and soluble in Acetone and bought from sigma company. The bacterium used in this test is a strain of Salmonella thyphimurium (TA100) that carries a selective mutation in its Histidine Operon. We also added Microsome to improve anticancer activity of this two triterpenoids. In this study, inhibition percentage from mutation was 83% for ursolic acid and 76.4 % for oleanolic acid in presence of Microsome ( and 77.6 % for Ursolic Acid and 69.8 % for Oleanolic Acid in absence of Microsome) . Therefore , presence of anti mutation Ursolic Acid and oleanolic acid along with mutagen substance, reduced quantity of back mutation and Inhibition over 40 % recommended as a powerful antimutation substance. Therefore, apple peel has large amount of active Phytochemicals, with Antimutation and Anticarcinogen activity and Ursolic Acid has more antimutation activity than Oleanolic acid

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In this paper, estimation of survey precision for nonlinear estimators is considered and an equation is presented based on sampling and nonsampling variances. Furthermore, by considering the response error model in surveys and the estimators of variance components, some relations are presented to computation of survey precision for nonlinear estimators. As an application case for the results, two typical data sets are considered and survey precisions of a nonlinear estimator are computed in the both data sets.

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Abstra
The metapelites of North of Golpayegan show that these rocks can be divided into four categories based on mineral assemblages: chloritoid- garnet- biotite- schist, garnet- biotite- muscovite- schist, staurolite bearing garnet- biotite- muscovite schist and Kyanite bearing staurolite- biotite- muscovite- schist.
The appearance of chloritoid in chloritoid- garnet- biotite schists shows green schist facies. Garnets in garnet- biotite- muscovite schists shows 3 stage of growth and syn-tectonic formation.
The appearance of staurolite in staurolite bearing garnet- biotite- muscovite schists signifies the beginning of amphibolite facies. The absence of zoning in the staurolite contained in these schists suggests the formation and growth of this mineral in a prograde metamorphism.
The thermodynamic study of these rocks shows that North of Golpayegan's metapelites were formed within a temperature range of 480 – 560oC and a pressure range of 1.6 – 4.1 kbar. These results are consistent with the minerals' paragenetic evidence and show that effect of metamorphism on North of Golpayegan's pelitic sediments is to lower amphibolite facies (Epidote amphibolite).

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Plant diseases especially plant viruses cause significant crop decrease. Meristem culture is the most important method for virus free plant production. The aim of this investigation was to establish an effective protocol for callus induction and plant regeneration from meristem culture of potato (Solanum tuberosum L. var.premier) tissues. Calli were induced from axillary meristems of Solanum tuberosum L. (cv. Premier) on MS medium containing 2,4-D (0, 0.5, 1, 1.5, 2 and 2.5 mg/l) and kinetin (0, 0.5, 1 and 1.5 mg/l). MS medium with 2 mg/l 2,4-D and 1.5 mg/l kinetin, was effective for callus induction. Plantlets were regenerated after 9 weeks. In terms of shoot regeneration and its growth, 1 mg/l 2,4-D and 1.5 mg/l kinetin were the most effective treatment. Maximum number of leaves were produced by plantlets growing on MS medium containing 1 mg/l 2,4-D and 1 mg/l kinetin. High frequency of root formation and its growth were observed on the same medium.

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Aluminum toxicity is one of the most important limiting factors for plant growth and development in acidic soil (pH <5.5). Soil acidity and consequently availability of Al in the soil can be accelerated by some farming practices and acid rain. The mechanisms of Aluminum toxicity have not been elucidated yet. The first response of the plant to aluminium toxicity is the inhibition of root elongation, that is apparently resulted from increasing of cell wall cross links. Therefore, the effect of aluminium on activity and gene expression of enzymes involved in phenolic compounds biosynthesis such as phenylalanine ammonialyase and peroxidase was investigated in this research.To this end, the flax seeds grown in Hoagland’s solution were treated with 0, 50 and 100 &muM aluminium (as AlCl3. 6H2O). The results showed that aluminium decreased root growth but increased wall bound phenolics content, compared with those of the control plants. Increase of the activity of peroxidase especially in ionically and covalently fractions in Al-treated roots was consisted with reducing root growth.  Increased activity, PAL expression and lignin contents were observed in higher concentrations of aluminum. The investigation of the expression of peroxidase isozymes, Flxper1 and Flxper3 suggested that Flxper3 is the isozyme which is more involved in aluminium toxicity in flax roots.  

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در این مقاله سه نوع از مسائل معکوس سهموی از نوع هدایت گرمایی و تشعشع گرمایی به روش تجزیه آدومیان بررسی می شود و برای حل این نوع مسائل معکوس از یک شرط فوق ¬اضافی در یک نقطه داخلی ناحیه مفروض مسأله استفاده می شود. این روش با سرعت همگرایی بالا، تقریب عددی از جواب دقیق مسأله بدون نیاز به خطی¬سازی یا گسسته سازی می¬دهد. در واقع روش تجزیه آدومیان، نیاز به حل کردن هر سیستم خطی یا غیرخطی از معادلات جبری را از بین می¬برد. نتایج عددی به دست آمده از این روش حاکی از دقت و سرعت بالای این روش است

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In this article, tunneling resonance (transmission coefficient, current density and negative differential resistance) has been studied for Al_x Ga_1-x As / GaAs triangular double quantum wells. Time dependent Schrodinger equation has been used for triangular quantum wells structures accompanied with Airy function. Transmission and reflection coefficients before and after applying external electrical field were obtained for two symmetrical triangular quantum well in terms of effective mass approximation as a function of structural  parameters such as well width, barrier width, well depth and applied voltage. Results showed a negative differential resistance at this kind of quantum wells.

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            Inverse time - dependent heat source   problems have an important role in many branches
     of science and  technology. The aim of this paper is to solve these classes of problems using a 
     variational  iteration  method(VIM). The method applied does not require discretization  of the
      region, as in the case  of classical methods based on the finite difference method,  the boundary
     element method  or the other methods.  Applying this method, we obtain a stable approximation
      to an  unknown source term  in an inverse heat equation   from  over-specified data  that the  source
      term is only time - dependent.  Some numerical examples using this approach are presented and
     discussed

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The spin-1/2 Ising chain in presence of a magnetic field and the Dzyaloshinskii-Moriya interaction is considered. First, using the rotation operator the model is transformed to the anisotropic spin-1/2 XXZ model in presence of a longitudinal magnetic field and then, using the fermionization technique and mean field approximation, the diagonalized Hamiltonian is obtained. The thermodynamic behavior of the specific heat is studied. It is found that the maximum value of the specific heat shows dual behavior. Specially, in the region of fields less than quantum critical field, it decreases by increasing field but behaves inversely in the region of the magnetic fields more than the quantum critical field. In addition, the magnetization process is studied and it is shown that the Dzyaloshinskii-Moriya interaction influences the magnetization process. 

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Today, induced pluripotent cells (iPS) have been recognized as a new and good cell source for cell therapy. In this study, we examined whether human iPS cells, cultured on scaffolds, can differentiate into definitive endodermal cells, as precursor for hepatocytes, pancreatic and lung cells. Embryoid bodies (EBs) composed of iPS cells then EBs were seeded on electrospinning nanofiber scaffold (PCL). The cells were differentiated into definitive endoderm by using IDE1(induced definitive endoderm). Expression of definitive endoderm markers including Sox17, FoxA2 and Gsc were confirmed by Immunocytochemistry attaining and RT-PCR analysis. In the present study, cells morphology and cells viability were evaluated by using a scanning electron microscopy and MTT assay respectively.The results of this study demonstrated the positive effect of 3D cultures, by using suitable factors, on definitive endoderm differentiation.definitive endoderm by using IDE1(induced definitive endoderm). Expression of definitive endoderm markers including Sox17, FoxA2 and Gsc were confirmed by Immunocytochemistry attaining and RT-PCR analysis. In the present study, cells morphology and cells viability were evaluated by using a scanning electron microscopy and MTT assay respectively.The results of this study demonstrated the positive effect of 3D cultures, by using suitable factors, on definitive endoderm differentiation.

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Acid rain, which is a wet form of gaseous air pollutants, is formed when air pollutants such as SO₂, NO₂, CO₂ in atmosphere combine with water vapor of clouds. With the addition of concentration of these pollutants the amount of acid rain is increases. Acid rain that is the mixture of sulphuric acid, nitric acid and carbonic acid lead to change in the soil like the decrease in pH, nutrient liberation, the increase of releasing in toxic metals and the decline in fertility of soil that these cases results negative effects on plants. In present work wheat plants irrigated  and leaf spraied with  four treatments of acid rain which contain sulphuric acid and nitric acid with  pH= 2.5, 3.5, 4.5, 5.6 for a period of 32 days, whereas, control plants irrigated and leaf spraied by normal water at  pH= 7.4 . According to the results control plants in whole of growth and physiological indexes were better than treatments of  acid rain at pH= 2.5 and 3.5, also plants of acid rain treatment at pH= 4.5 and 5.6, were lower in other factors except photosynthetic rate, pigment content and carbohydrate content than control plants. Also acid rain at pH= 2.5 and 3.5 causes white spot in both surface of  leaf and tip and border atrophy.

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Recently, concern over environmental and health effects of massive use of the antibiotics has let to growth of the bio-control agents application. Poly-&beta-hydroxybutyrate (PHB) is a natural polymer that can be depolymerized into water-soluble short-chain fatty acid monomers and acts as a microbial control agent. In this study, the effects of partially replacing the diet of Siberian sturgeon fingerlings with 2% and 5% PHB were investigated. Community level physiological profile (CLPP) was used to analyze anaerobic bacterial metabolic diversity in Siberian sturgeon fingerlings hindgut by using Biolog™ Ecoplate microplates. The results indicated that PHB increased metabolic activity in anaerobic bacteria in sturgeon hindgut. Also Lorenz curve and the Shannon index of Biolog™ Ecoplate data revealed that anaerobic metabolic potential of the bacterial community was different in the PHB-treated fishes as compared with the control situation.

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The mechanism of soybean(Glycine max L.cv.Gorgan 3) response to drought stress was evaluated. The plants were grown in pots under 23 ± 2°C temperature and 14000 lux light intensity and 14hr photoperiod. When first leaf appeard, three irrigation treatments occurred that consisted as one every day(control), once in three(mild stress) and in five days(sever stress).During 15 days the plants were irrigated an amount of 150 ml. The effect of irrigation treatment on the soluble sugar, total protein, proline, phenolic compound, chlorophyll content and nitrate reductase activity was studied.The results showed that in the root soluble sugar and proline content in mild and sever stress significantly increased while in the stem and the leaf these compound considarably increased under sever stress the total protein ,chlorophyll a,b and nitrate reductase activity in leaf especially decreased in sever stress. Also the decrease phenolic compound in leaf under this condition was significant