Heat flow diversion in supported graphene nanomesh

Yousefzadi Nobakht, A.,Shin, S.,Kihm, K.D.,Marable, D.C.,Lee, W. Pergamon Press ; Elsevier Science Ltd 2017 Carbon Vol.123 No.-

<P>Redirection of energy carrier propagation by geometric confinement is studied through the analysis of in-plane and cross-plane thermal transport within various graphene nanomesh (GNM) configurations using molecular dynamics (MD) simulations. As the transport channel width decreases with an increase in porosity, the effect of redirection increases; thus, the in-plane thermal conductivity of large-porosity GNM is more dependent on hole arrangement. Since higher porosities weaken the GNM structure due to a larger population of broken bonds, carbon atoms within the graphene structures are more easily influenced by interactions with the substrate silicon (Si) block. Subsequently, increase in porosity leads to the decrease of interfacial thermal resistance. At higher porosities, lower interfacial resistance and in-plane thermal conductivity cause diversions (and redirections) in heat flow from the GNM to the underlying Si substrate. Our study suggests that this method of heat flow redirection can be applied as an effective means to control and manage heat transfer within numerous applications; extension to the improved conductivity calculation accuracy can also be achieved through the inclusion of this diversion analysis. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Radioprotective effect of mefenamic acid against radiation-induced genotoxicity in human lymphocytes

Hosseinimehr, Seyed Jalal,Nobakht, Reyhaneh,Ghasemi, Arash,Pourfallah, Tayyeb Allahverdi The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: Mefenamic acid (MEF) as a non-steroidal anti-inflammatory drug is used as a medication for relieving of pain and inflammation. Radiation-induced inflammation process is involved in DNA damage and cell death. In this study, the radioprotective effect of MEF was investigated against genotoxicity induced by ionizing radiation in human blood lymphocytes. Materials and Methods: Peripheral blood samples were collected from human volunteers and incubated with MEF at different concentrations (5, 10, 50, or $100{\mu}M$) for two hours. The whole blood was exposed to ionizing radiation at a dose 1.5 Gy. Lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis blocked binucleated lymphocyte. Results: A significant decreasing in the frequency of micronuclei was observed in human lymphocytes irradiated with MEF as compared to irradiated lymphocytes without MEF. The maximum decreasing in frequency of micronuclei was observed at $100{\mu}M$ of MEF (38% decrease), providing maximal protection against ionizing radiation. Conclusion: The radioprotective effect of MEF is probably related to anti-inflammatory property of MEF on human lymphocytes.

Radioprotective effect of mefenamic acid against radiation-induced genotoxicity in human lymphocytes

Seyed Jalal Hosseinimehr,Reyhaneh Nobakht,Arash Ghasemi,Tayyeb Allahverdi Pourfallah 대한방사선종양학회 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: Mefenamic acid (MEF) as a non-steroidal anti-inflammatory drug is used as a medication for relieving of pain and inflammation. Radiation-induced inflammation process is involved in DNA damage and cell death. In this study, the radioprotective effect of MEF was investigated against genotoxicity induced by ionizing radiation in human blood lymphocytes. Materials and Methods: Peripheral blood samples were collected from human volunteers and incubated with MEF at different concentrations (5, 10, 50, or 100 μM) for two hours. The whole blood was exposed to ionizing radiation at a dose 1.5 Gy. Lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis blocked binucleated lymphocyte. Results: A significant decreasing in the frequency of micronuclei was observed in human lymphocytes irradiated with MEF as compared to irradiated lymphocytes without MEF. The maximum decreasing in frequency of micronuclei was observed at 100 μM of MEF (38% decrease), providing maximal protection against ionizing radiation. Conclusion: The radioprotective effect of MEF is probably related to anti-inflammatory property of MEF on human lymphocytes

Deep extractive desulfurization of oil over 12-Molibdophosphoric acid encapsulated in metal-organic frameworks

Ezzat Rafiee,Narges Nobakht 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.1

A desulfurization process for model oil and real oil was investigated based on the chemical oxidation of mixed sulfur containing compounds in the presence of nitrogen compounds (indole and quinoline) using hydrogen peroxide as oxidizing agent and dodecamolibdophosphoric acid (H3PMo12O40) encapsulated in a kind of metal-organic framework (HKUST-1) as PMo@HKUST-1. The effect of isopropanol, ethanol and acetonitrile as extractive solvent and 1-ring (toluene, xylene and mesitylene) and 2-ring (naphthalene) aromatic hydrocarbons in desulfurization of model oil was studied. The desulfurization of sulfur-containing compounds was accelerated in the presence of aromatic hydrocarbons. In fact, a higher desulfurization efficiency of the heterogeneous catalyst could be achieved with system containing a polar solvent in contact with an aromatic hydrocarbon. Quinoline had no effect on oxidative desulfurization (ODS) reaction, whereas indole had a slightly negative effect. Presence of aromatic compounds had slightly positive effect on ODS reaction.

Hybrid thermal seasonal storage and solar assisted geothermal heat pump systems for greenhouses

Ataei, Abtin,Hemmatabady, Hoofar,Nobakht, Seyed Yahya Techno-Press 2016 Advances in energy research Vol.4 No.1

In this research, optimum design of the combined solar collector, geothermal heat pump and thermal seasonal storage system for heating and cooling a sample greenhouse is studied. In order to optimize the system from technical point of view some new control strategies and functions resulting from important TRNSYS output diagrams are presented. Temperatures of ground, rock bed storage, outlet ground heat exchanger fluid and entering fluid to the evaporator specify our strategies. Optimal heat storage is done with maximum efficiency and minimum loss. Mean seasonal heating and cooling COPs of 4.92 and 7.14 are achieved in series mode as there is no need to start the heat pump sometimes. Furthermore, optimal parallel operation of the storage and the heat pump is studied by applying the same control strategies. Although the aforementioned system has higher mean seasonal heating and cooling COPs (4.96 and 7.18 respectively) and lower initial cost, it requires higher amounts of auxiliary energy either. Soil temperature around ground heat exchanger will also increase up to $1.5^{\circ}C$ after 2 years of operation as a result of seasonal storage. At the end, the optimum combined system is chosen by trade-off between technical and economic issues.

Parathyroid Hormone Gene rs6256 and Calcium Sensing Receptor Gene rs1801725 Variants are not Associated with Susceptibility to Colorectal Cancer in Iran

Mahmoudi, Touraj,Karimi, Khatoon,Arkani, Maral,Farahani, Hamid,Nobakht, Hossein,Dabiri, Reza,Asadi, Asadollah,Zali, Mohammad Reza Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: Substantial evidence from epidemiological studies has suggested that increased levels of calcium may play a protective role against colorectal cancer (CRC). Given the vital role of calcium sensing receptor (CaSR) and parathyroid hormone (PTH) in the maintenance of calcium homeostasis, we explored whether the rs1801725 (A986S) variant located in exon 7 of the CaSR gene and the rs6256 variant located in exon 3 of PTH gene might be associated with CRC risk. Materials and Methods: In this study 860 subjects including 350 cases with CRC and 510 controls were enrolled and genotyped using PCR-RFLP methods. Results: We observed no significant difference in genotype or allele frequencies between the cases with CRC and controls for both CaSR and PTH genes either before or after adjustment for confounding factors including age, BMI, sex, smoking status, and family history of CRC. Furthermore, no evidence for effect modification of any association of rs1801725 and rs6256 variants and CRC by BMI, sex, or tumor site was observed. In addition, there was no significant difference in genotype and allele frequencies between the normal weight (BMI < $25kg/m^2$) cases and overweight/obese (BMI ${\geq}25kg/m^2$) cases for the two SNPs. Conclusions: These data indicated that the CaSR gene A986S variant is not a genetic contributor to CRC risk in the Iranian population. Furthermore, our results suggest for the first time that PTH gene variant does not affect CRC risk. Nonetheless, further studies with larger sample size are needed to validate these findings.

Lack of Associations between Vitamin D Metabolism-Related Gene Variants and Risk of Colorectal Cancer

Mahmoudi, Touraj,Karimi, Khatoon,Arkani, Maral,Farahani, Hamid,Nobakht, Hossein,Dabiri, Reza,Asadi, Asadollah,Vahedi, Mohsen,Zali, Mohammad Reza Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Purpose: With regard to the protective effect of vitamin D against colorectal cancer (CRC), we evaluated genetic variants that might influence vitamin D metabolism: vitamin D receptor (VDR), vitamin D binding protein (GC), vitamin D 25-hydroxylase (CYP2R1), and vitamin D 25-hydroxy 1-alpha hydroxylase (CYP27B1). Materials and Methods: A total of 657 subjects, including 303 cases with CRC and 354 controls were enrolled in this case-control study. All 657 were genotyped for the four gene variants using PCR-RFLP methods. Results: In this study, no significant difference was observed for VDR (rs2238136), GC (rs4588), CYP2R1 (rs12794714), and CYP27B1 (rs3782130) gene variants in either genotype or allele frequencies between the cases with CRC and the controls and this lack of difference remained even after adjustment for age, BMI, sex, smoking status, NSAID use, and family history of CRC. Furthermore, no evidence for effect modification of the variants and CRC by BMI, sex, or tumor site was observed. Conclusions: Our findings do not support a role for VDR, GC, and CYP27B1 genes in CRC risk in our Iranian population. Another interesting finding, which to our knowledge has not been reported previously, was the lack of association with the CYP2R1 gene polymorphism. Nonetheless, our findings require confirmation and possible roles of vitamin D metabolism-related genes in carcinogenesis need to be further investigated.

Is there an Association between Variants in Candidate Insulin Pathway Genes IGF-I, IGFBP-3, INSR, and IRS2 and Risk of Colorectal Cancer in the Iranian Population?

Karimi, Khatoon,Mahmoudi, Touraj,Karimi, Negar,Dolatmoradi, Hesamodin,Arkani, Maral,Farahani, Hamid,Vahedi, Mohsen,Parsimehr, Elham,Dabiri, Reza,Nobakht, Hossein,Asadi, Asadollah,Zali, Mohammad Reza Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

Background: Several epidemiological studies have shown associations between colorectal cancer (CRC) risk and type 2 diabetes and obesity. Any effects would be expected to be mediated through the insulin pathway. Therefore it is possible that variants of genes encoding components of the insulin pathway play roles in CRC susceptibility. In this study, we hypothesized that polymorphisms in the genes involving the insulin pathway are associated with risk of CRC. Materials and Methods: The associations of four single nucleotide polymorphisms (SNPs) in IGF-I (rs6214), IGFBP-3 (rs3110697), INSR (rs1052371), and IRS2 (rs2289046) genes with the risk of CRC were evaluated using a case-control design with 167 CRC cases and 277 controls by the PCR-RFLP method. Results: Overall, we observed no significant difference in genotype and allele frequencies between the cases and controls for the IGF-I, IGFBP-3, INSR, IRS2 gene variants and CRC before or after adjusting for confounders (age, BMI, sex, and smoking status). However, we observed that the IRS2 (rs2289046) GG genotype compared with AA+AG genotypes has a protective effect for CRC in normal weight subjects (p=0.035, OR=0.259, 95%CI= 0.074-0.907). Conclusions: These findings do not support plausible associations between polymorphic variations in IGF-I, IGFBP-3, INSR, IRS2 genes and risk of CRC. However, the evidence for a link between the IRS2 (rs2289046) variant and risk of CRC dependent on the BMI of the subjects, requires confirmation in subsequent studies with greater sample size.