Search

IntroductionThe use of agricultural waste to produce biodegradable containers is an appropriate option to solve the problem of biomass accumulation resulting from the cultivation of crops such as rice. The highest amount of agricultural waste compared to the area under cultivation is related to wheat straw and rice straw, respectively. After wheat, rice is the most important agricultural product in human nutrition. According to the World Food Organization, the area under rice cultivation in the world is about 150 million hectares. The use of rice straw as a raw material for disposable cellulosic dishes can prevent straw residues in paddy fields, improve the deficiency of cellulosic raw materials, and reduce the use of plastic containers and the dangers thereof. Rice straw is a significant source for making cellulosic containers, but after making containers, hydrophobicity and microbial hazards can be among the problems of making these types of containers. The coating technique is one of the best solutions for resolving hydrophobicity and microbial problems. Coverage is very important and necessary to increase the shelf life of agricultural products and maintain their quality. Waxes are the best preventative methods against moisture and water vapor loss, and beeswax is one of the best edible waxes with these properties. The antibacterial properties of coatings with natural antioxidants will help solve the cellulose containers' problem. The main objectives of this study were to evaluate the endurance, hydrophobicity and antimicrobial activity of rice straw degradable cellulosic dishes.Materials and MethodsIn order to obtain the raw material for the manufacture of cellulosic dishes, the straw was digested with 10% and 20% sodium hydroxide, and then to weigh the hydrophobicity tests, tensile strength index and brightness, 120 Gr paper was made. Concentrations of 1, 2, 5 and 10% of the wax solution in ethanol solution were prepared and used as the first coating to improve the hydrophobicity. The nettle extract encapsulated with royal seed gum as the second coating to improve the antibacterial activity. Hydrophobicity and antimicrobial properties of the samples were measured and compared. The cup mold specimen was made of 2-piece steel and made using appropriate rice straw paste and coating with the appropriate concentration of the sample in disposable cellulose.Results and DiscussionThe results showed that increasing the amount of sodium hydroxide in baking conditions increased the tensile strength and the degree of clarity, but it had no effect on hydrophobicity. As the concentration of baking soda (sodium hydroxide) increases, so does the brightness. Increasing the concentration of sodium hydroxide increases the tensile strength, and the increase in tensile strength due to the increase in the percentage of sodium hydroxide can be due to the increase in the ability to form bonds between fibers due to the release of lignin. Honey wax with a 5% concentration was the most optimal coating for hydrophobic cellulose containers. With increasing wax concentrations in ethanol solvents from 1 to 10 percent, water absorption by the paper made from rice straw has decreased by approximately 93 percent. Adding royal seed gum and nettle extract has a positive effect on the diameter of the halo and has antimicrobial properties. Honey wax with 5% and 10% concentration with nano-encapsulated nettle extract with royal seed gum was selected as the most suitable coating to improve antibacterial activity.ConclusionDue to the characteristics of rice straw and the experiments shown, rice straw can be considered as a suitable alternative to oil resources in the production and usage of disposable tableware. Rice straw has the potential to be used as a cellulose source for the production of disposable containers, and honey wax with a 5% concentration and nano-encapsulated nettle extract can improve the hydrophobic and antimicrobial properties as the airtight coating of the dishes.

Background and Objectives: Musculoskeletal disorders are among the most common injuries in dentists. Therefore, the present study was conducted to determine the relationship between students' level of knowledge of the principles of ergonomics and body position during dental treatments. Materials and Methods: In this descriptive study, 41 dental students of Guilan University of Medical Sciences at the clinical level were enrolled in 2017. Ergonomic condition was assessed using Rapid Entire Body Assessment (REBA) standard index. Data were analyzed using Spearman's correlation coefficient test and independent t-test. Results: The results showed 21 (51.2%) students were at high and also 15 (36.6 %) students were at very high-risk levels. Also a negative correlation was found between the level of knowledge and REBA score (r=-0.137, p=0.036). Conclusion: Most students were at high risk for musculoskeletal problems and low ergonomic awareness. The results of the study raise the need for ergonomic knowledge training. [ABSTRACT FROM AUTHOR]

Background and Objective: An activity performed through a new motional pattern and very intensively often leads to a kind of muscle soreness whose indicator is delayed onset of pain, which is called Delayed Onset Muscle Soreness (DOMS). This study was done to determine the effect of vitamin C and E supplementation on lipid peroxidation and delayed onset muscle soreness in professional basketball players. Methods: In this clinical trial study, 24 male professional basketball players were randomly divided into four groups including vitamin C (1000 mg), vitamin E (800 IU), vitamin C (500 mg) + vitamin E (400 IU) and placebo (Glucose 500 mg). Supplement was consumed two hours before and 24 hours after leg press and scuat exercise. Blood samples were collected before the first supplementation and immediately (post- exercise), 24 hour and 48 hour after exercises. Serum creatine kinase (CK), malondialdehyde (MDA), vitamin C and vitamin E and the level of perceived muscle soreness were evaluated. Results: MDA in Vitamin E group significantly decreased in the 24-hr to 48-hr after the exercise in compared to bignning of exercise (P<0.05). Serum CK significantly increased 24-hr and 48-hr after the exercise in all groups (P<0.05). Muscle pain perception non significantly increased after the exercise in all groups in compare to baseline level. Conclusion: Short period supplementationin of vitamin C and E, either alone or in combination can not reduce pain and muscle damage and lipid peroxidation following the leg press and scuat exercise in professional basketball players. [ABSTRACT FROM AUTHOR]

Myrtus communis L. aerial parts have been used in traditional medicine for the treatment of inflammatory disease. In this study 350 mice were divided into three main groups: negative (saline), positive (morphine or diclofenac) controls, and test groups. The acute toxicity was assessed for 2 days. Antinociceptive activity was performed using hot plate and writhing tests. The anti-inflammatory effect was investigated using xylene-induced ear edema and a cotton pellet test. According to phytochemical screening, the extracts contained tannins, alkaloids, and flavonoids. The LD50 values of the aqueous and ethanolic extracts were 0.473 and 0.79 g/kg, respectively. In hot plate test, the aqueous and ethanolic extracts showed significant antinociceptive activity that was inhibited by naloxone. The extracts exhibited antinociceptive activity against acetic acid-induced writhing and also showed significant activity against acute inflammation which was dose dependent for aqueous extract. The ethanolic (0.05 g/kg) and aqueous extracts (0.005, 0.015, and 0.03 g/kg) demonstrated anti-inflammatory effects against chronic inflammation. The aqueous and ethanolic extracts of the aerial parts of M communis L. showed antinociceptive effects and these may be mediated by opioid receptors., (Copyright © 2011. Published by Elsevier B.V.)