Numerical investigation of yaw angle effects on propulsive characteristics of podded propulsors

Reza Shamsi,Hassan Ghassemi 대한조선학회 2013 International Journal of Naval Architecture and Oc Vol.5 No.2

The present paper deals with the problems of yaw angle effects on podded propulsor performance. The study aims at providing insights on characteristics of podded propulsors in azimuthing condition. In this regard, a wide numerical simulation that concerned yaw angle effect measurement on podded propeller performance was performed. The Reynolds-Averaged Navier Stokes (RANS) based solver is used in order to study the variations of hydrodynamic characteristics of podded propulsor at various angles. At first, the propeller is analyzed in open water condition in absence of pod and strut. Next flow around pod and strut are simulated without effect of propellers. Finally, the whole unit is studied in zero yaw angle and azimuthing condition. Structured and unstructured mesh techniques are used for single propeller and podded propulsor. The performance curves of the propeller obtained by numerical method are compared and verified by the experimental results. The characteristic parameters including the torque and thrust of the propeller,the axial force and side force of unit are presented as function of velocity advance ratio and yaw angle. The results shows that the propeller thrust, torque and podded unit forces in azimuthing condition depend on velocity advance ratio and yaw angle.

Numerical investigation of yaw angle effects on propulsive characteristics of podded propulsors

Shamsi, Reza,Ghassemi, Hassan The Society of Naval Architects of Korea 2013 International Journal of Naval Architecture and Oc Vol.5 No.2

The present paper deals with the problems of yaw angle effects on podded propulsor performance. The study aims at providing insights on characteristics of podded propulsors in azimuthing condition. In this regard, a wide numerical simulation that concerned yaw angle effect measurement on podded propeller performance was performed. The Reynolds-Averaged Navier Stokes (RANS) based solver is used in order to study the variations of hydrodynamic characteristics of podded propulsor at various angles. At first, the propeller is analyzed in open water condition in absence of pod and strut. Next flow around pod and strut are simulated without effect of propellers. Finally, the whole unit is studied in zero yaw angle and azimuthing condition. Structured and unstructured mesh techniques are used for single propeller and podded propulsor. The performance curves of the propeller obtained by numerical method are compared and verified by the experimental results. The characteristic parameters including the torque and thrust of the propeller, the axial force and side force of unit are presented as function of velocity advance ratio and yaw angle. The results shows that the propeller thrust, torque and podded unit forces in azimuthing condition depend on velocity advance ratio and yaw angle.

RNAi and miRNA in Viral Infections and Cancers

Mollaie, Hamid Reza,Monavari, Seyed Hamid Reza,Arabzadeh, Seyed Ali Mohammad,Shamsi-Shahrabadi, Mahmoud,Fazlalipour, Mehdi,Afshar, Reza Malekpour Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Since the first report of RNA interference (RNAi) less than a decade ago, this type of molecular intervention has been introduced to repress gene expression in vitro and also for in vivo studies in mammals. Understanding the mechanisms of action of synthetic small interfering RNAs (siRNAs) underlies use as therapeutic agents in the areas of cancer and viral infection. Recent studies have also promoted different theories about cell-specific targeting of siRNAs. Design and delivery strategies for successful treatment of human diseases are becomingmore established and relationships between miRNA and RNAi pathways have been revealed as virus-host cell interactions. Although both are well conserved in plants, invertebrates and mammals, there is also variabilityand a more complete understanding of differences will be needed for optimal application. RNA interference (RNAi) is rapid, cheap and selective in complex biological systems and has created new insight sin fields of cancer research, genetic disorders, virology and drug design. Our knowledge about the role of miRNAs and siRNAs pathways in virus-host cell interactions in virus infected cells is incomplete. There are different viral diseases but few antiviral drugs are available. For example, acyclovir for herpes viruses, alpha-interferon for hepatitis C and B viruses and anti-retroviral for HIV are accessible. Also cancer is obviously an important target for siRNA-based therapies, but the main problem in cancer therapy is targeting metastatic cells which spread from the original tumor. There are also other possible reservations and problems that might delay or even hinder siRNA-based therapies for the treatment of certain conditions; however, this remains the most promising approach for a wide range of diseases. Clearly, more studies must be done to allow efficient delivery and better understanding of unwanted side effects of siRNA-based therapies. In this review miRNA and RNAi biology, experimental design, anti-viral and anti-cancer effects are discussed.

High Resolution Melting Curve Assay for Detecting rs12979860 IL28B Polymorphisms Involved in Response of Iranian Patients to Chronic Hepatitis C Treatment

Fateh, Abolfazl,Aghasadeghi, Mohammad Reza,Keyvani, Hossein,Mollaie, Hamid Reza,Yari, Shamsi,Tasbiti, Ali Reza Hadizade,Ghazanfari, Morteza,Monavari, Seyed Hamid Reza Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Background: A recent genome-wide association study (GWAS) on patients with chronic hepatitis C (CHC) treated with peginterferon and ribavirin (pegIFN-${\alpha}$/RBV) identified a single nucleotide polymorphism (SNP) on chromosome 19 (rs12979860) which was strongly associated with a sustained virological response (SVR). The aim of this study was twofold: to study the relationship between IL28B rs12979860 and sustained virological response (SVR) to pegIFN-${\alpha}$/RVB therapy among CHC patients and to detect the rs12979860 polymorphism by high resolution melting curve (HRM) assay as a simple, fast, sensitive, and inexpensive method. Materials and Methods: The study examined outcomes in 100 patients with chronic hepatitis C in 2 provinces of Iran from December 2011 to June 2013. Two methods were applied to detect IL28B polymorphisms: PCR-sequencing as a gold standard method and HRM as a simple, fast, sensitive, and inexpensive method. Results: The frequencies of IL28B rs12979860 CC, CT, and TT alleles in chronic hepatitis C genotype 1a patients were 10% (10/100), 35% (35/100), and 6% (6/100) and in genotype 3a were 13% (13/100), 31% (31/100), and 5% (5/100), respectively. In genotype 3a infected patients, rs12979860 (CC and CT alleles) and in genotype 1a infected patients (CC allele) were significantly associated with a sustained virological response (SVR). The SVR rates for CC, CT and TT (IL28B rs12979860) were 18%, 34% and 4%, respectively. Multiple logistic regression analysis identified two independent factors that were significantly associated with SVR: IL-28B genotype (rs 12979860 CC vs TT and CT; odds ratio [ORs], 7.86 and 4.084, respectively), and HCV subtype 1a (OR, 7.46). In the present study, an association between SVR rates and IL28B polymorphisms was observed. Conclusions: The HRM assay described herein is rapid, inexpensive, sensitive and accurate for detecting rs12979860 alleles in CHC patients. This method can be readily adopted by any molecular diagnostic laboratory with HRM capability and will be clinically beneficial in predicting treatment response in HCV genotype 1 and 3 infected patients. In addition, it was demonstrated that CC and CT alleles in HCV-3a and the CC allele in HCV-1a were significantly associated with response to pegIFN-${\alpha}$/RBV treatment. The present results may help identify subjects for whom the therapy might be successful.

Determination of an Effective Wedge Angle by Combination of Two Arbitrary Universal Wedge Fields in Radiation Therapy of Cancer Patients with Megavoltage Photon Beams

Shamsi, Azin,Birgani, Mohammad Javad Tahmasebi,Behrooz, Mohammad Ali,Arvandi, Sholeh,Fatahiasl, Jafar,Maskny, Reza,Abdalvand, Neda Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

Background: Wedge filters are commonly used in radiation oncology for eliminating hot spots and creating a uniform dose distribution in optimizing isodose curves in the target volume for clinical aspects. These are some limited standard physical wedges ($15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$),or creating an arbitrary wedge angle, like motorized wedge or dynamic wedge,${\ldots}$ The new formulation is presented by the combination of wedge fields for determining an arbitrary effective wedge angles. The isodose curves also are derived for these wedges. Materials and Methods: we performed the dosimetry of Varian Clinac 2100C/D with Scanditronix Wellhofer water blue phantom, CU500E, OmniPro - Accept software and 0.13cc ionization chamber for 6Mv photon beam in depth of 10cm (reference depth) for universal physical wedges ($15^{\circ}$, $30^{\circ}$, $45^{\circ}$, and $60^{\circ}$) and reference field $10.10cm^2$. By combining the isodose curve standard wedge fields with compatible weighting dose for each field, the effective isodose curve is calculated for any wedge angle. Results: The relation between a given effective wedge angle and the weighting of each combining wedge fields was derived. A good agreement was found between the measured and calculated wedge angles and the maximum deviation did not exceed $3^{\circ}$. The difference between the measured and calculated data decreased when the combined wedge angles were closer. The results are in agreement with the motorized single wedge appliance in the literature. Conclusions: This technique showed that the effective wedge angle that is obtained from this method is adequate for clinical applications and the motorized wedge formalism is a special case of this consideration.

Evaluation of Human Papilloma Virus Infection in Patients with Esophageal Squamous Cell Carcinoma from the Caspian Sea Area, North of Iran

Yahyapour, Yousef,Shamsi-Shahrabadi, Mahmoud,Mahmoudi, Mahmoud,Siadati, Sepideh,Shahryar, Shefaei Shahryar,Shokri-Shirvani, Javad,Mollaei, Hamid,Monavari, Seyed Hamid Reza Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Introduction: HPV has been found repeatedly in esophageal squamous cell carcinoma (ESCC) tissues. However, reported detection rates of HPV DNA in these tumors have varied markedly. Differences in detection methods, sample types, and geographic regions of sample origin have been suggested as potential causes of variation. We have reported that infection of HPV DNA in ESCC tumors depends on anatomical sites of esophagus of the patients from Mazandaran, north of Iran. Materials and Methods: HPV DNA was examined in 46 upper, 69 middle and 62 lower third anatomical sites of esophageal squamous cell carcinoma specimens collected from Mazandaran province in north Iran, near the Caspian Littoral as a region with high incidence of ESCC. HPV L1 DNA was detected using Qualitative Real time PCR and MY09/MY11 primers. Results: 28.3% of upper, 29% of middle and 25.8% of lower third of ESCC samples were positive for HPV DNA. 13.6% for males and 14.1% for females were HPV positive in all samples. Conclusions: HPV infection is about one third of ESCC in this area. Findings in this study increase the possibility that HPV is involved in esophageal carcinogenesis. Further investigation with a larger sample size is necessary.

Expression Analysis of Two Cancer-testis Genes, FBXO39 and TDRD4, in Breast Cancer Tissues and Cell Lines

Seifi-Alan, Mahnaz,Shamsi, Roshanak,Ghafouri-Fard, Soudeh,Mirfakhraie, Reza,Zare-Abdollahi, Davood,Movafagh, Abolfazl,Modarressi, Mohammad Hossein,Kazemi, Golnesa,Geranpayeh, Lobat,Najafi-Ashtiani, Mi Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Breast cancer accounts for one third of new cancer cases among women. The need for biomarkers for early detection is the stimulus to researchers to evaluate altered expression of genes in tumours. Cancer-testis (CT) genes are a group with limited expression in normal tissues except testis but up-regulation in a wide variety of cancers. We here evaluated expression of two CT genes named FBXO39 and TDRD4 in 32 invasive ductal carcinoma samples, 10 fibroadenomas and 6 normal breast tissue samples, in addition to two breast cancer cell lines, MCF-7 and MDA-MB-231, by the means of quantitative real time RT-PCR. FBXO39 showed significant up-regulation in invasive ductal carcinoma samples in comparison with normal samples. It also was expressed in both cell lines and after RHOXF1 gene knock down it was down-regulated in MCF-7 but up-regulated in the MDA-MB-231 cell line. TDRD4 was not expressed in the MCF-7 cell line and any of the tissue samples except testis. However, it was expressed in MDA-MB-231 and was up-regulated after RHOXF1 gene knock down. Our results show that FBXO39 but not TDRD4 can be used for cancer detection and if proved to be immunogenic, might be a putative candidate for breast cancer immunotherapy.

Refusal Self Efficacy, Self Esteem, Smoking Refusal Skills and Water Pipe (Hookah) Smoking among Iranian Male Adolescents

Karimy, Mahmood,Niknami, Shamsaddin,Heidarnia, Ali Reza,Hajizadeh, Ebrahim,Shamsi, Mohsen Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: Tobacco use among adolescents is a major public health concern, and identifying predictors of smoking is necessary for planning prevention programs. The present study examined the relationship between refusal self efficacy, self esteem, smoking refusal skills and water pipe (hookah) smoking among Iranian male adolescents. Materials and Methods: A cross-sectional study was conducted with 380 Iranian male adolescents aged between 15-19 years selected by multistage sampling. The participants completed an anonymous, voluntary, self-report questionnaire. Variables independently associated with water pipe (WP) smoking were identified by multiple logistic regression analysis. Results: The mean age of the participants was $16.7{\pm}1.3$ years. The prevalence of WP smoking was 17.3%. Logistic regression analysis revealed that knowledge (OR=0.56; 95% CI: (0.37-0.79), attitude (OR=0.69; 95% CI: (0.52-0.89), self esteem (OR=0.67; 95% CI: (0.55-0.82), smoking refusal skills (OR=0.73; 95% CI: (0.55-0.87), and self efficacy (OR=.82; 95% CI: (0.61-0.93) were all signifcant prediting facotrs for adolescents WP smoking. Conclusions: The findings have implications for public health interventions. Indeed, self efficacy and smoking refusal skills should be considered when developing tailored measures for the prevention of WP smoking among adolescents.

Analytical Consideration of Surface Dose and Kerma for Megavoltage Photon Beams in Clinical Radiation Therapy

Birgani, Mohammad Javad Tahmasebi,Behrooz, Mohammad Ali,Razmjoo, Sasan,Zabihzadeh, Mansour,Fatahiasl, Jafar,Maskni, Reza,Abdalvand, Neda,Asgarian, Zeynab,Shamsi, Azin Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

Background: In radiation therapy, estimation of surface doses is clinically important. This study aimed to obtain an analytical relationship to determine the skin surface dose, kerma and the depth of maximum dose, with energies of 6 and 18 megavoltage (MV). Materials and Methods: To obtain the dose on the surface of skin, using the relationship between dose and kerma and solving differential equations governing the two quantities, a general relationship of dose changes relative to the depth was obtained. By dosimetry all the standard square fields of $5cm{\times}5cm$ to $40cm{\times}40cm$, an equation similar to response to differential equations of the dose and kerma were fitted on the measurements for any field size and energy. Applying two conditions: a) equality of the area under dose distribution and kerma changes in versus depth in 6 and 18 MV, b) equality of the kerma and dose at $x=d_{max}$ and using these results, coefficients of the obtained analytical relationship were determined. By putting the depth of zero in the relation, amount of PDD and kerma on the surface of the skin, could be obtained. Results: Using the MATLAB software, an exponential binomial function with R-Square >0.9953 was determined for any field size and depth in two energy modes 6 and 18MV, the surface PDD and kerma was obtained and both of them increase due to the increase of the field, but they reduce due to increased energy and from the obtained relation, depth of maximum dose can be determined. Conclusions: Using this analytical formula, one can find the skin surface dose, kerma and thickness of the buildup region.