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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: International Journal of Engineering, Transactions A: Basics
- نوع مقاله: Journal Article
- کلمات کلیدی: Response surface methodology,Nanocomposite,Biodegradability,corn starch,Soil burial
- چکیده:
- چکیده انگلیسی: In this study, biodegradation of corn starch/glycerol/Na-MMT nanocomposites by soil burial tests were carried out for up to 6 months. Films were prepared by casting method according to central composite design and response surface methodology was applied for analysis of the results. The effects of formulation on the water solubility, contact angle and tensile strength of starch films were investigated. Increasing in Na-MMT content decreased biodegradability; while presence of glycerol, increased it. The effect of nanoparticles content might have been attributed to interactions between starch and Na-MMT that further prevented enzymatic attack on the biopolymer. In addition, the films with higher initial contact angle and lower water solubility revealed slower biodegradation. The effect of glycerol is debated because higher hydrophilicity and weaker mechanical properties enhanced the amylase attack on the samples. Furthermore, weight loss due to soluble matters caused an increase to account of the biodegradability. By increasing in glycerol amount as a water holding agent, the films could store sufficient water content for microbial activities around the buried samples. According to FTIR spectra for partially biodegraded films, the intensity of the peaks associated with starch glycosidic linkages decreased which indicates the action of alpha-amylase produced by soil microorganisms.
- انتشار مقاله: 11-10-1348
- نویسندگان: M. Vossoughi,Iran Alemzadeh,Amir Heydari
- مشاهده
- جایگاه : پژوهشی
- مجله: Environmental Energy and Economic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Economic Growth,Developing countries,Developed Countries,Government Size,panel data
- چکیده:
- چکیده انگلیسی: Due to the importance of the government size impact on economic growth, the current study investigates the impact of government size on economic growth in economies of the developed and developing countries by using a panel data approach over the period 1990-2010. The results indicate that government size has positive effect on economic growth and negative effect on per capita production growth in developed countries, but, it has negative and significant effect on economic growth and per capita production growth in developing countries. Therefore, reducing the government size is very important for increasing the economic growth in developing countries such as Iran. Also, based on the results, investment growth and consumption expenditure growth have positive and significant effect on economic growth and per capita production growth in both developed and developing countries. However, Trade openness effect on economic growth and per capita production growth is positive and significant in developed countries, but is negative in developing countries.
- انتشار مقاله: 13-07-1397
- نویسندگان: Hadi Rafie,Samira Heydarian,Afsaneh Zareei,Ali Alisoofi
- مشاهده
- جایگاه : پژوهشی
- مجله: Chemical Methodologies
- نوع مقاله: Journal Article
- کلمات کلیدی: MTT assay,HLPNPs,Etoposide,Central composite design,Nanoprecipitation
- چکیده:
- چکیده انگلیسی: Lipid polymer hybrid nanoparticles [LPHNPs] are a system of nanoparticles which are a mixture of lipid monolayer shell and biodegradable polymer core developed for intelligent drug delivery of anti-cancer drugs. The present study aimed to develop and optimize LPHNPs for targeted delivery of etoposide anticancer drug through designing an experiment with Response Surface Methodology [RSM] and Central Composite Design [CCD] with quantitative control of three independent variables of lipid, polymer and polyvinyl alcohol [PVA] percentage which examined their effect on nanoparticle size and encapsulation efficiency [EE]. LPHNPs were prepared by one-step nanoprecipitation method. The results showed the optimizing of the tested values of polymer, lipid and %PVA. Lipid-polymer hybrid formulation was reported to be about 14% after 80 hr. The cytotoxicity effect of etoposide-containing LPHNPs for lung cancer cell lines A-549 and Calu6 showed higher antitumor activity compared with the free drug used. Further, the results showed that the high polymer concentration led to more space for drug enclosure and created a relatively compact matrix; therefore, the drug encapsulation efficiency increased as the amount of polymer increased. In LPHNPs, increasing the amount of polymer, lipid and increasing the percentage of PVA used in nanocarrier synthesis generally improved particle size and encapsulation efficiency. The results also showed that LPHNPs could be effective for the delivery of hydrophobic drugs such as etoposide.
- انتشار مقاله: 17-03-1399
- نویسندگان: Fatemeh Zare Kazemabadi,Amir Heydarinasab,Azim Akbarzadehkhiyavi,Mehdi Ardjmand
- مشاهده
- جایگاه : پژوهشی
- مجله: Chemical Methodologies
- نوع مقاله: Journal Article
- کلمات کلیدی: cancer,Solubility,Pharmacy,Nanoliposomes,Blood
- چکیده:
- چکیده انگلیسی: One of the most common causes of death in today's society is cancer. The treatments used in the treatment of cancers have their own side effects that have created many problems in the complete treatment of cancer. In classical and conventional drug delivery systems, the drug is distributed aimlessly and generally throughout the body, and the cells take part in the drug from the blood based on their position relative to the drug. As a result, a significant amount of the drug is wasted and eliminated without being used by the body. The most important disadvantages of the old methods of drug delivery are drug wastage, high cost of raw materials, the occurrence of side effects related to the dose, physical and chemical incompatibilities, as well as clinical drug interactions. Nano-liposomes are nanometer-scale liposomes that are one of the most useful drug delivery systems in the field of drug release and retention, which both provides a higher level than liposomes and increases solubility and access to bioavailability as well as improved drug release. Important reasons for the use of nano-liposomes in the pharmaceutical industry are their similarity to cell membranes and trapping of hydrophobic and hydrophilic substances, drug delivery to the target tissue, control of drug flow in the bloodstream and good biocompatibility. Another important feature of nano-liposomes is the coating of water-soluble drugs in the central aqueous portion and fat-soluble drugs within its bilayer membrane. Nano liposomes can be effective in reducing drug toxicity and increasing drug efficacy.
- انتشار مقاله: 17-02-1399
- نویسندگان: Ali Hatami,Amir Heydarinasab,Azim Akbarzadehkhiyavi,Farshid Pajoum Shariati
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Pacific Journal of Medical Toxicology
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Amphetamines,High Pressure Liquid Chromatography,N-Methyl-3,4-methylenedioxyamphetamine,Street Drugs
- چکیده:
- چکیده انگلیسی: Background:Ecstasy, mainly composed of 3,4-methylenedioxymethamphetamine (MDMA), is one of the most popular addictive synthetic drugs. This study was aimed to investigate the amount of MDMA in the ecstasy tablets seized in West Azerbaijan province, northwest Iran and also to assess the relationship between the physicochemical and morphological characteristics of the tablets.
Methods: MDMA content of ecstasy tablets was analyzed using high-performance liquid chromatography method. Flow rate was 3 mL/min and mobile phase consisted of a mixture of acetonitrile and water containing triethylamine (pH = 3.2). The fluorescence spectrophotometer detector set at an excitation and emission wavelength of 220 and 306 nm, respectively. The retention time of ecstasy on this system was 2.2 minutes. The calibration curve was linear (R2= 0.999) over the concentrations ranging from 0.2 to 2 µg/ml. The limit of detection and the limit of quantitation were found to be 0.06 µg/L and 0.19 µg/L, respectively with six times repetition.
Results: In this study, 85 ecstasy tablets were analyzed. Mean weight of the tablets was 275.6 ± 70.4 (range: 158.5-403.3) mg. Mean MDMA content of the tablets was 30.53 ± 23.23 (range: 0.05-70.7) mg. The tablets were classified into 8 groups based on their morphological features (color and logo). Considering the tablet groups, physicochemical features of the tablets (weight, MDMA content, and MDMA to weight ratio) were significantly different (P < 0.001). Correlation analysis showed that the MDMA content and weight of tablets were significantly correlated (P = 0.04).
Conclusion: There is variability in the physicochemical properties of ecstasy tablets available in the black market for illicit drugs in northwest Iran. This variability may potentially put abusers at increased risk of overdose due to inadvertent excess ingestion of the tablets to achieve desired effects and also experiencing more harm due to tablets adulterants.- انتشار مقاله: 10-03-1393
- نویسندگان: Reza Ghafari,Amir Heydari,Mohammad Reza Vardast,Azam Akbari
- مشاهده