فهرست مطالب محمدرضا اویسی

The aim of this study was to investigate the possibility of using lead contaminated water in surface irrigation and subirrigation and its effect on silage maize yield. In this regard, lysimeter experiments were conducted in the College of Agriculture and Natural Resources, University of Tehran in 2017 in the form of a completely randomized factorial project with six treatments in three replications and a total of 18 experimental plots. Treatments included: Surface irrigation with lead-contaminated water (SP), Surface irrigation with fresh water as control treatment (SC), Subirrigation with lead-contaminated water and water table depth of 50 cm (50P), Subirrigation with fresh water and water table depth of 50 cm (50C), Subirrigation with lead-contaminated water and water table depth of 75 cm (75P), and finally, Subirrigation with fresh water and water table depth of 75 cm (75C). The results showed that the effect of irrigation management on plant height, plant dry weight and maize silage yield at 1% probability level, wet plant weight and maize wet weight at 5% level was significant and it had no effect on maize dry weight. Also, pollution had no effect on growth and yield and components of maize yield. The results also showed there was a 2.25 mg of lead per one kg of maize dry matter in the SP treatment, which this amount is in the group of low pollution according to the World Health Organization (WHO), No lead was observed in the plant samples of the 50P and 75P treatments. On the other hand, the highest maize yield was recorded in the 75P treatment with 49.65 t/ha and then in the 50P treatment with 47.04 t/ha. Crop yield increased by 36% and 29% in the 75P and 50P treatments compared to the control treatment, respectively. It is noteworthy that the amount of lead metal stabilized and rised in the subirrigation treatment was out of reach of the plant and there was no problem in terms of pollution and maize yeild.

The objective of the present study is to review the theory of government in the political idea of Ibn Khaldun. To this aim and using a hermeneutic approach, the theory of Asabiyyah (social cohesion) as the foundation of Ibn Khaldun’s political doctrine, the emergence of government and its contributing factors, the causes of government’s fall, variety of governments and its best type were discussed in Ibn Khaldun’s theory of government. The method of study was descriptive analysis and the results showed that Ibn Khaldun has been among the first thinkers in the world studying the concept of government and theorizing the origin, definition, way of establishment, types, the ideal form, components, functions, and its fall. Since his theory has the three elements of a scientific theory, that is to say concordance with the objective instances, multi relationships between the concepts in the theory, and the coherence of perception in various circumstances, it can be recognized as one of the first theories of government and has the potential of academic and international publication.

International relations as a scientific phenomenon has several pillars, one of which is culture as the beliefs, traditions and habits of each nation, such a way that one group of international relations theorists, including Huntington, sees culture as a cause of international tensions, while another group sees culture as a cause of international convergences. Therefore, now that the field of culture and cultural issues is considered as an important pillar of international relations in the international system arena, it is necessary to study the function of culture in international relations with a scientific view. So, in this article, the aim is to find the answer to the question that what is the special function of culture as the most fundamental characteristic of any nation in the context of the international system and the field of international relations? Therefore, we have collected the materials using a library method and studied them in a descriptive-analytical manner. Finally, we found that culture, due to its interaction with globalization, has led to the reinforcement of soft power, facilitation of international trade, rapid exchange and internationalization of science, rapid transmission of news, and some other results in international relations.

They are involved in free radicals by causing oxidative stress in chronic diseases such as cancer, atherosclerosis, and diabetes and also in the aging process. Antioxidants are the best way to fight free radicals. Plants are rich sources of natural antioxidants and total phenolic.                       

This study was designed to measure the amount of total phenol and antioxidant activity of malt beverages in Tehran market.                                                                                                         

In this study, 123 samples of non-alcoholic beer in Tehran market (domestic and imported) were prepared. Antioxidant activity was measured by FRAP (Ferric Reducing Ability of Plasma) method and total phenolic content was measured by Folin reagent and by spectrophotometer. The standard concentration of total phenolic compounds was measured using the gallic acid standard curve.                 

The highest content of total antioxidants and total phenols in sample No. 2 were 4.29 µg /ml and 5.80 µg /ml, respectively. The lowest content of total antioxidants and total phenol in sample No. 6 were 1.33 µg / ml and 1.19 µg/ml, respectively. There was a significant difference between the amount of total phenol and total antioxidant capacity in domestic and imported samples and had a higher antioxidant content of imported samples. Which was related to the malting process and the raw materials used. The total phenolic content of domestic malted drinks and imported malted drinks were in the range of 1.10-4.18 μM and 1.58-4.33 μM, respectively. But there was no significant difference between the two groups in terms of antioxidant content. It was observed that the content of total phenol and total antioxidants in classical malted drinks was higher than malted drinks with different flavors.                 

Discussion and Conclusion:

The results show that classic malted drinks are a potential source of antioxidants and total phenols.

Pectin is a complex polysaccharide consisting mainly of esterified D-galacturonic acid residues in an alpha-(1-4) chain. The acid groups along the chain are largely esterifed with methoxy groups in the natural product. It has broad applications in both food and pharmaceutical industries where it acts as gelling and thickening agent. The present study was designed to determine the galacturonic acid content and degree of pectin esterification. In the current study Record cultivar of sunflower grown in Varamin region of Iran was selected for pectin extraction. The residue was dried in a drying chamber and stored at 4°C before use. The pectin was extracted by using 0.75% sodium hexameta phosphate at the pH of 3, 4 and 5 with the temperature of 75, 85 and 95°C for 20 and 40 minutes and the optimum conditions for the extraction of pectin, galacturonic acid content and the degree of esterification was studied. The highest yield was obtained at the pH of 5 and temperature of 95°C for 20 min. Galacturonic acid content or degree of purity related to the pectin was from 66.5% to 86%. Degree of esterification of extracted pectin was from 21% to 33% that clearly indicates the low methoxyl nature of the pectin. However, there were significant differences (p<0.05) between mentioned extraction condition factors, that is an important criterion for the quality of the pectin and the degree of esterification. It seems that the pectin extracted from sunflowers head show a high potential for commercial food applications.

Brassia family have an indole methyl glucosinolate named “Glucobrassecin”. One of degradation products of this glucosinolate is indole- 3- carbinole (13C) which has anticarcinogenic properties. Degradation of glucosinolates is caused by hydrolytic effect of mirosinase enzyme released by damaged plant cell. Most of the studies about the anticancer properties of 13C were done with animal studies.According to brassica tissica properties and existence of high amont of ascorbic acid (AA), 13C combinr with AA and produce ascorbigen an anticarcinogenic compound and as a source of AA. In this study, we used from the relationship of 13C to AA for measurement of 13C by Voltammetric method. For this pupose, voltammograms of ascorbic acid in citrate phosphate buffer with optimum pH = 3.2 and sweep rate of 7500 mv/s and concentrations of 1- 175 μg/ml were drawn and then under this condition, different concentrations of 13C were added to the highest concentration of ascorbic acid. Analysis of the result showed that curve of the curve of 13C with different concentrations versus current was logarithmic. Detection limit of 13C was 0.001 mM.Relative standard deviation of method repeatability for concentrations of 0.8 mM, 0.5 mM and 0.15 mM were 5.2%, 5% and 5.6% respectively. Curve of concentration against logarithm of current was linear and also sensitivity of method was – 2.65 log A/mM.