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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Expandable DNA repeat,Fragile X syndrome,Myotonic dystrophy,Huntington’s disease,Friedreich’s ataxia
- چکیده:
- چکیده انگلیسی: Background & Aims: Nearly 30 hereditary disorders in humans result from an increase in the number of copies of simple repeats in genomic DNA, including fragile X syndrome, myotonic dystrophy, Huntington’s disease, and Friedreich’s ataxia. One the most frequently occurring types of mutation is trinucleotide repeat expansion. The present study was conducted with the aim of investigating the cause and molecular mechanisms of repeat expansions DNA and their pathogenic mechanisms in diverse classes of genetic diseases. Methods: Scientific databases were searched using the keywords expandable DNA repeat fragile X, myotonic dystrophy, Huntington’s disease, and Friedreich’s ataxia. After primary screening, articles which were related to the studies topic were further considered and analyzed. Results: DNA repeats seem to be predisposed to such expansion due to their unusual structural features, which disrupt the cellular replication, repair, and recombination processes. The majority of these debilitating diseases are caused by repeat expansions in the noncoding regions of their resident genes. The pathogenic mechanism underling these disorders include loss of function in protein and gain of function in protein or ribonucleic acid (RNA). Conclusion: Although diseases caused by trinucleotide repeat expansion vary in their phenotypes, they are somewhat similar in their pathogenic mechanism and medical findings. It is likely that progress made in this field will be beneficial to patients who have other neurological diseases
- انتشار مقاله: 24-04-1395
- نویسندگان: Shahin Ramazi,Ali Fasihi,Maryam Godarziyan,Morteza Hashemzadeh-Chaleshtori
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Energetic materials,thermodynamic parameters,B12N12,Density functional theory (DFT),3-Picrylamino-1, 2, 4-triazole (PATO)
- چکیده:
- چکیده انگلیسی: In this study, the reaction of 3-Picrylamino-1, 2, 4-Triazole (PATO) with B12N12 was investigated by density functional theory in the B3LYP/6-31G(d) level of theory. There were two possible isomers for reaction of PATO with B12N12 via carbon and nitrogen atoms of triazole ring to the Born atom of B12N12 (I and II-isomers). Thermodynamic parameters of these reactions including formation Enthalpy changes (ΔHf), Gibbs free energy alterations (ΔGf) and Heat capacity (Cv) were calculated in the temperature range of 300-400K. Variations of density and dipole moment values of PATO after interaction were studied. Also, the frontier orbital energies, HOMO-LUMO gap, chemical hardness (η), electrophilicity index (ω), charge transferred (∆Nmax) and chemical potential (μ) were computed.
- انتشار مقاله: 29-12-1396
- نویسندگان: Maryam Godarzi,Roya Ahmadi,Reza Ghiasi,Mohammad Yousefi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of New Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: 1,thermodynamic parameters,tetrazolo [1,5-b][1,2,4]triazine , Density Functional Theory,5-diaminotetrazole,glyoxal
- چکیده:
- چکیده انگلیسی: In this article, synthesis of the explosive synthesis of tetrazolo [1,5-b][1,2,4]triazine from the reaction of 1,5-diaminotetrazole with glyoxal in different conditions of temperature, with density functional theory method were studied. For this purpose, at first the material contained in the both sides of reaction were geometrically optimized, then the calculation of the thermodynamic parameters performed on all of them. The amount of ∆H, ∆S and ∆G of this reaction at different temperatures in form of sum of parameters discrepancy in the products than reactants is obtained. And finally, the best temperature for the synthesis of explosive according to the obtained thermodynamic parameters were evaluated.
- انتشار مقاله: 05-10-1397
- نویسندگان: Rahim Faraji,Shahab Moeinian,Leila Fathahiyan,Maryam Godarzi,Ashkan Nasrolah Kalantari
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Density functional theory,explosives,PATO,Fullerene (C60)
- چکیده:
- چکیده انگلیسی: In this study, the adsorption of 3-picrylamino-1,2,4-triazole (PATO) On the surface of fullerene (C60) was evaluated by density functional theory using, Becke, three-parameter and Lee-Yang-Parr (B3LYP). PATO as a green fuel, is such a green material and environmental friendly, because after combustion it produces excessive amounts of N2 gas. Due to the importance of these materials in protecting environmental pollution as well as protecting fossil fuel reserves, it is necessary to research in this field. For this purpose, the structures of PATO, C60, and the PATO-C60 complexes were optimized geometrically. Then, IR and Frontier molecular orbital calculations were performed on them. The calculated energies: Gibbs free energy changes (ΔGad) and adsorption enthalpy changes (ΔHad) revealed that the adsorption process of PATO-C60 complexes are experimentally feasible, spontaneous and exothermic. The specific heat capacity values (CV) showed the heat sensitivity has reduced significantly in the PATO-C60 complexes. The N‒O and C‒N bond lengths and the density values demonstrated that PATO-C60 complexes have higher explosive velocity and blasting pressure in comparison to the pure blasting materials without C60. The Frontier molecular orbital parameters such as band gap, chemical hardness, electrophilicity, chemical potential and charge capacity were also studied.
- انتشار مقاله: 15-12-1397
- نویسندگان: Maryam Godarzi,Roya Ahmadi,Reza Ghiasi
- مشاهده