Abstract Background: Tattooing is among identified risk factor for blood-borne diseases. Objective: This study aims to determine the prevalence of tattooing during lifetime and in prisons and its related factors among Iranian prisoners. Methods: This is a cross-sectional study. The required data was obtained from hepatitis B and C surveillance surveys in prisons in 2015-2016 that was collected through face-to-face interview. 12,800 prisoners were selected by multi-stage random sampling from 55 prisons of 19 provinces in Iran. Weighted prevalence and associated factors (using Chi-Square test and multivariate logistic regression) were determined by Stata/SE 14.0 survey package. Results: Out of 12,800 prisioners, 11,988 participated in the study (93.6% participation rate). The prevalence of tattooing in lifetime and in prisons was 44.7% and 31.1% respectively. The prevalence of tattooing during lifetime was significantly associated with age < 35 years, being single, illiteracy, history of imprisonment, drug use, piercing during lifetime, extramarital sex and history of STI; the prevalence of tattooing in prison had a significant association with history of imprisonment, drug use, piercing in prison, and history of extramarital sex (p < 0.05). Study limitations: Information and selection bias was one of the study limitations. Conclusion: The results of this study showed that the prevalence of tattooing during lifetime and in prison among prisoners was significantly high especially in high-risk groups such as drug users and sexually active subjects. Given the role of tattooing, drug injection and sex in the transmission of blood-borne diseases, harm reduction programs are recommended to reduce these high-risk behaviors in prisons.

Abstract Background: Although not fully understood, oxidative stress has been implicated in the pathogenesis of different autoimmune diseases such as systemic sclerosis. Accumulating evidence indicates that oxidative stress can induce mitochondrial DNA (mtDNA) damage and variations in mtDNA copy number (mtDNAcn). Objective: The aim of this study was to explore mtDNAcn and oxidative DNA damage byproducts in peripheral blood of patients with systemic sclerosis and healthy controls. Methods: Forty six patients with systemic sclerosis and forty nine healthy subjects were studied. Quantitative real-time PCR used to measure the relative mtDNAcn and the oxidative damage (oxidized purines) of each sample. Results: The mean mtDNAcn was lower in patients with systemic sclerosis than in healthy controls whereas the degree of mtDNA damage was significantly higher in cases as compared to controls. Moreover, there was a negative correlation between mtDNAcn and oxidative DNA damage. Study limitations: The lack of simultaneous analysis and quantification of DNA oxidative damage markers in serum or urine of patients with systemic sclerosis and healthy controls. Conclusion: These data suggest that alteration in mtDNAcn and increased oxidative DNA damage may be involved in the pathogenesis of systemic sclerosis.

Resumo Vários estudos de associação entre os polimorfismos genéticos nos receptores α e β de estrogênio e a escoliose idiopática da adolescência (EIA) foram publicados nas últimas duas décadas. No entanto, a associação com a EIA, especialmente em diferentes subgrupos étnicos, continua a ser controversa. Assim, o presente estudo investigou esses dados inconclusivos por meio de uma metanálise para avaliar sistematicamente essa associação. Uma pesquisa bibliográfica foi realizada nas bases de dados PubMed, ISI Web of Science, EMBASE, SCOPUS, EBSCO, Cochrane Library, China National Knowledge Infrastructure (CNKI) e Wanfang até 20 de janeiro de 2018. A força de associação foi avaliada por meio de razões de probabilidades (RPs) e intervalos de confiança de 95% (ICs95%). Um total de 12 estudos de caso-controle, com 4.304 casos de EIA e 3.123 controles, atenderam aos critérios de inclusão do presente estudo. As RPs combinadas indicaram que os polimorfismos ESRα XbaI A > G, ESRα PvuII T > C e ESRβ AlwNI T > C podem não estar significativamente associados ao risco geral de desenvolvimento de EIA. No entanto, observou-se uma associação significativa entre o polimorfismo ESRα XbaI A > G e a EIA sob o modelo homozigótico (GG versus AA; RP = 1,448; IC95%: 1,052-1,993; p = 0,023). Esta metanálise sugere que os polimorfismos ESRα XbaI A > G, ESRα PvuII T > C e ESRβ AlwNI T > C podem não estar associados ao risco geral de desenvolvimento de EIA. No entanto, ESRα XbaI A > G pode influenciar a suscetibilidade de desenvolver EIA entre indivíduos asiáticos. Considerando o tamanho e a variação étnica limitada da amostra, outros estudos de maior escala são necessários para obter uma estimativa mais precisa das associações.

Abstract Several association studies of genes polymorphisms on estrogen receptors-α and β with respect to adolescent idiopathic scoliosis (AIS) have been published in the past two decades. However, the association with AIS, especially among different ethnic subgroups, still remains controversial. Thus, we investigated these inconclusive data by performing a meta-analysis to systematically evaluate the association. A literature search was conducted in the PubMed, ISI Web of Science, EMBASE, SCOPUS, EBSCO, Cochrane Library, China National Knowledge Infrastructure (CNKI) and Wanfang databases until January 20, 2018. The strength of relationship was assessed using odds ratios (ORs) and 95% confidence intervals (95%CIs). A total of 12 case-control studies with 4,304 cases of AIS and 3,123 controls met our criteria. The pooled ORs indicated that the ESRα XbaI A > G, ESRα PvuII T > C and ESRβ AlwNI T > C polymorphisms were not significantly associated with the risk of developing AIS in the overall analysis. However, we found a significant association between the ESRα XbaI A > G polymorphism and AIS under the homozygote model (GG versus AA; OR = 1.448, 95%CI: 1.052-1.993; p = 0.023). The present meta-analysis suggests that the ESRα XbaI A > G, ESRα PvuII T > C and ESRβ AlwNI T > C polymorphisms may not be associated with the risk of developing AIS in the overall analysis. However, ESRα XbaI A > G might have an influence on the susceptibility to develop AIS among Asians. Considering the limited sample size and ethnicity, further larger studies are needed to provide a more precise estimation of the associations.

ABSTRACT The virtual social networks have brought the new lifestyle and thinking the way to its addresses and influence on the addresses’ lifestyle by representing the dominant relationships on life. This research investigates the role of virtual social networks on Iranian citizens’ interest in body management. The methodology of this research is surveying and research tool is questionnaire. The statistical population of this research includes the dwelled citizens in Tehran in 2018, and 420 people were selected as the sample volume using a multistage cluster sampling method. The results of research show the positive and significant relationship between using the virtual social network and body management, wearing style, appearance management, consumption style, and between body management and membership duration in virtual social network and assertiveness interest. In addition, increasing dependence and activity in virtual social networks, in particular, Instagram, has led users to move toward wearing style, appearance, nutrition regime, body appearance, makeup style and tended to consumerism.

RESUMEN Las redes sociales virtuales han traído el nuevo estilo de vida y pensando el camino a sus direcciones e influyen en el estilo de vida de las direcciones al representar las relaciones dominantes en la vida. Esta investigación investiga el papel de las redes sociales virtuales sobre el interés de los ciudadanos iraníes en la gestión del cuerpo. La metodología de esta investigación es la encuesta y la herramienta de investigación es el cuestionario. La población estadística de esta investigación incluye a los ciudadanos habitados en Teherán en 2018, y se seleccionaron 420 personas como el volumen de la muestra utilizando un método de muestreo por conglomerados en varias etapas. Los resultados de la investigación muestran la relación positiva y significativa entre el uso de la red social virtual y la gestión del cuerpo, el estilo de uso, la gestión de la apariencia, el estilo de consumo, y entre la gestión del cuerpo y la duración de la membresía en la red social virtual y el interés por la asertividad. Además, el aumento de la dependencia y la actividad en las redes sociales virtuales, en particular, Instagram, ha llevado a los usuarios a avanzar hacia el estilo de uso, la apariencia, el régimen de nutrición, la apariencia corporal, el estilo de maquillaje y tiende al consumismo.

Abstract Background: Acute kidney injury (AKI) is a frequent event after cardiac surgery with increased mortality and morbidity. We explored frequency, risk factors, and associated morbidity and mortality of AKI after isolated coronary artery bypass grafting (CABG) surgery at a single institution. Methods: All consecutive adults undergoing CABG surgery from March 2013 to October 2016 were assessed for development and severity of AKI based on Acute Kidney Injury Network (AKIN) criteria. The patients were also investigated regarding their need for renal replacement therapy (RRT), predictive risk factors, and associated outcomes, including duration of mechanical ventilation, mortality, intensive care unit (ICU) and hospital length of stay. Results: Of 1737 patients in the study, 275 (15.8%) developed AKI. Twenty-five (12.8%) cases required RRT. Patients with AKI had longer ventilation time, ICU and hospital length of stay (P<0.001). Mortality rates were 28 (10.2%) and 22 (1.5%) in patients with and without AKI, respectively (P<0.001). There was a strong association between advanced age (aOR=1.016, 95% CI=1.002-1.030, P=0.028), diabetes (aOR=1.36, 95% CI=1.022-1.809, P=0.035), on-pump surgery (aOR=2.63, 95% CI=1.543-4.483, P<0.001), transfusion of more than 1 unit of red blood cells (aOR=2.154, 95% CI=1.237-3.753, P=0.007), and prolonged mechanical ventilation and development of AKI (aOR=2.697, 95% CI=1.02407.071, P<0.001). AKI was seen less frequently in those with opium abuse (aOR=0.613, 95% CI=0.409-0.921, P=0.018). Conclusion: We demonstrated that advanced age, diabetes, on-pump surgery, red blood cell transfusion, and prolonged mechanical ventilation were independent positive risk factors for the development of AKI after isolated CABG while opium abuse was a protective factor.

RESUMO Introdução: O polimorfismo da matriz metaloproteinase-7 (MMP-7) -181A>G tem sido relatado como associado à suscetibilidade dos cânceres colorretal (CRC) e gástrico (GC), mas os resultados desses estudos anteriores foram inconsistentes ou controversos. Objetivo: Elaborar metanálise para avaliar a associação do polimorfismo -181A> G da MMP-7 com o risco de CRC e GC. Métodos: Revisão da literatura publicada avaliando essa associação no PubMed, Web of Science, Google Acadêmico e outras bases de dados até 25 de abril de 2018. Odds ratio (OR) e o intervalo de confiança de 95% (IC) foram calculados usando dados aleatórios ou modelo de efeitos fixos. Resultados: Um total de 19 estudos caso-controle, que incluíram 11 trabalhos sobre CRC (2.169 casos de CCR e 2.346 controles) e oito sobre GC (1.545 casos de GC e 2.366 controles) foram identificados. Houve associação significativa entre o polimorfismo MMP-7 -181A>G e o risco de GC sob o modelo homozigoto (GG vs. AA: OR=1,672, IC 95% 1,161-2,409, p=0,006) e o modelo recessivo (GG vs. GA + AA: OR=1,672, IC 95% 1,319-2,554, p=0,001), mas não com CRC. Por análise de subgrupos com base na etnia, um risco aumentado de CRC e GC foi encontrado apenas entre os asiáticos. Conclusões: Esta metanálise sugere que os polimorfismos MMP-7 -181A>G estão associados ao risco de GC, mas não ao CRC. No entanto, estes resultados mostraram claramente que o polimorfismo MMP-7 -181A>G aumentou significativamente o risco de CRC apenas em asiáticos.

ABSTRACT Introduction: The matrix metalloproteinase-7 (MMP-7) gene -181A>G polymorphism has been reported to be associated with colorectal cancer (CRC) and gastric cancer (GC) susceptibility, yet the results of these previous results have been inconsistent or controversial. Aim: To elaborate a meta-analysis to assess the association of -181A>G polymorphism of MMP-7 with CRC and GC risk. Methods: Published literature evaluating the association from PubMed, Web of Science, Google Scholar and other databases were retrieved up to April 25, 2018. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using random- or fixed-effects model. Results: A total of 19 case-control studies, which included eleven studies on CRC (2,169 CRC cases and 2,346 controls) and eight studies on GC (1,545 GC cases and 2,366 controls) were identified. There was a significant association between MMP-7 -181A>G polymorphism and GC risk under the homozygote model (GG vs. AA: OR=1.672, 95% CI 1.161-2.409, p=0.006) and the recessive model (GG vs. GA+AA: OR=1.672, 95% CI 1.319-2.554, p=0.001), but not with CRC. By subgroup analysis based on ethnicity, an increased risk of CRC and GC was found only among Asians. Conclusions: This meta-analysis suggests that MMP-7 -181A>G polymorphisms is associated with GC risk, but not with CRC. However, our results clearly showed that the MMP-7 -181A>G polymorphism significantly increased the risk of CRC only in Asians.

RESUMO OBJETIVO: Tem havido crescente interesse no estudo da associação entre polimorfismos do gene mutL homólogo 1 humano (hMLH1) e risco de câncer colorretal (CRC). No entanto, os resultados de estudos anteriores não são conclusivos. Assim, uma meta-análise foi conduzida para obter uma estimativa mais precisa dos efeitos desse gene. MÉTODOS: Uma pesquisa abrangente foi realizada nas bases de dados PubMed, Embase, Chinese Biomedical Literature até 10 de janeiro de 2018. Odds ratio (OR) com 95% de intervalo de confiança (IC) foi utilizado para avaliar a força da associação. RESULTADOS: Finalmente, foram identificados 38 estudos de casos e controles em 32 publicações, atendendo aos nossos critérios de inclusão. Houve 14 estudos com 20.668 casos e 19.533 controles em hMLH1 −93G>A, 11 estudos com 5.786 casos e 8.867 controles em 655A>G e cinco estudos com 1.409 casos e 1.637 controles em 1151T>Um polimorfismo. Os resultados combinados mostraram que os polimorfismos 655A>G e 1151T>A estavam significativamente associados ao risco de CRC, enquanto que o polimorfismo −93G>A não estava significativamente associado ao risco de CRC. Quanto à etnia, os polimorfismos de −93G>A e 655A>G foram associados ao risco aumentado de CRC entre os asiáticos, mas não entre os caucasianos. Mais interessante, a análise de subgrupos indicou que 655A>G pode aumentar o risco de CRC em subgrupos PCR-RFLP e HB. CONCLUSÃO: Inconsistente com a meta-análise anterior, esta meta-análise mostra que os polimorfismos hMLH1 655A>G e 1151T>A podem ser fatores de risco para CRC. Além disso, o polimorfismo −93G>A está associado à susceptibilidade do CRC na população asiática.

SUMMARY OBJECTIVE: There has been increasing interest in the study of the association between human mutL homolog 1 (hMLH1) gene polymorphisms and risk of colorectal cancer (CRC). However, results from previous studies are inconclusive. Thus, a meta-analysis was conducted to derive a more precise estimation of the effects of this gene. METHODS: A comprehensive search was conducted in the PubMed, EMBASE, Chinese Biomedical Literature databases until January 1, 2018. Odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of the association. RESULTS: Finally, 38 case-control studies in 32 publications were identified met our inclusion criteria. There were 14 studies with 20668 cases and 19533 controls on hMLH1 −93G>A, 11 studies with 5,786 cases and 8,867 controls on 655A>G and 5 studies with 1409 cases and 1637 controls on 1151T>A polymorphism. The combined results showed that 655A>G and 1151T>A polymorphisms were significantly associated with CRC risk, whereas −93G>A polymorphism was not significantly associated with CRC risk. As for ethnicity, −93G>A and 655A>G polymorphisms were associated with increased risk of CRC among Asians, but not among Caucasians. More interestingly, subgroup analysis indicated that 655A>G might raise CRC risk in PCR-RFLP and HB subgroups. CONCLUSION: Inconsistent with previous meta-analyses, this meta-analysis shows that the hMLH1 655A>G and 1151T>A polymorphisms might be risk factors for CRC. Moreover, the −93G>A polymorphism is associated with the susceptibility of CRC in Asian population.

RESUMO CONTEXTO: O promotor-1082 A/polimorfismo G (rs1800896) do gene da interleucina-10 (IL-10) é amplamente relatado e considerado por ter um papel significativo no risco de câncer gástrico, porém os resultados são inconsistentes. OBJETIVO: Para esclarecer melhor esta associação, realizou-se uma meta-análise para investigar as associações de IL-10-1082 A/polimorfismo G com câncer gástrico. MÉTODOS: Artigos elegíveis foram identificados através de pesquisa de bases de dados PubMed, Web of Science e Google Scholar até 3 de agosto de 2017. Razões de possibilidades (OR) com intervalo de confiança de 95% correspondente (CIs) foram usados para avaliar a associação. RESULTADOS: Um total de 30 estudos de caso-controle, 6.101 casos e com 8.557 controles foram incluídos nesta meta-análise. Em geral, uma associação significativa entre IL-10-1082 A/G polimorfismo e risco de câncer gástrico foi observada sob o modelo de alelo (G vs A: OR=1.305, 95% CI=1.076-1.584; P=0.007), no modelo heterozigoto (GA vs AA: OR=1.252, 95% CI=1.252-1.054; P=0.011) e modelo dominante (GG+GA vs AA: OR=1.264, 95% CI=1.053-1.516; P=0.012). Na análise de subgrupo pela etnia, foi encontrado risco aumentado de câncer gástrico em asiáticos sob o modelo de alelo (G vs A: OR=1.520, 95% CI=1.172-1.973; P=0.002), modelo heterozigoto (GG+GA vs AA: OR=1.571, 95% CI=1.023-2.414; P= 0.039), e modelo dominante (GG+GA vs AA: OR=1.448, 95% CI=1.152-1.821; P=0.002), mas não entre a população caucasiana e latina. CONCLUSÃO: Estes resultados sugeriram que a IL-10-1082 A/polimorfismo G (rs1800896) pode contribuir para a suscetibilidade de câncer gástrico, especialmente entre os asiáticos.

ABSTRACT BACKGROUND: The promoter -1082 A/G (rs1800896) polymorphism of Interleukin-10 (IL-10) gene have been widely reported and considered to have a significant role on gastric cancer risk, but the results are inconsistent. OBJECTIVE: To clarify the association, we conducted a meta-analysis to investigate the associations IL-10 -1082 A/G polymorphism with gastric cancer. METHODS: Eligible articles were identified by searching databases including PubMed, Web of Science, and Google Scholar up to August 03, 2017. Odds ratios (OR) with corresponding 95% confidence intervals (CIs) were used to assess the association. RESULTS: A total of 30 case-control studies with 6,101 cases and 8,557 controls were included in this meta-analysis. Overall, a significant association between IL-10 -1082 A/G polymorphism and gastric cancer risk was observed under the allele model (G vs A: OR=1.305, 95% CI=1.076-1.584; P=0.007), heterozygote model and (GA vs AA: OR=1.252, 95% CI=1.252-1.054; P=0.011) and dominant model (GG+GA vs AA: OR=1.264, 95% CI=1.053-1.516; P=0.012). In the subgroup analysis by ethnicity, increased gastric cancer risk were found in Asians under the allele model (G vs A: OR=1.520, 95% CI=1.172-1.973; P=0.002), homozygote model (GG+GA vs AA: OR=1.571, 95% CI=1.023-2.414; P= 0.039), heterozygote model (GA vs AA: OR=1.465, 95% CI=1.192-1.801; P≤0.001) and dominant model (GG+GA vs AA: OR=1.448, 95% CI=1.152-1.821; P=0.002), but not among Caucasian and Latinos populations. CONCLUSION: These results suggested that the IL-10 -1082 A/G (rs1800896) polymorphism might contribute to the gastric cancer susceptibility, especially among Asians.

Resumen Para investigar la diversidad y explicar las relaciones del rendimiento de aceite esencial con rasgos morfológicos, 84 poblaciones de T. polycephalum fueron sembradas en el campo utilizando diseño de bloques completos al azar (BCA) con tres réplicas en el Instituto de Investigación de Bosques y Pastizales, Teherán, Irán en 2013-2014. Los datos fueron colectados para la fecha de floración, días de grado de crecimiento (DGC), número de tallos, altura de planta, rendimiento de materia seca (MS), porcentaje de aceite esencial y rendimiento de aceite esencial. Las relaciones entre las características agronómicas se determinaron mediante correlación, regresión y análisis factorial. La distancia genética y la clasificación del genotipo, se determinaron mediante análisis de conglomerados. El rendimiento de MS se correlacionó positivamente con la altura de la planta, cobertura del dosel, número de tallos y rendimiento de aceite (p <0.01), mientras que el% de aceite esencial se correlacionó negativamente con la altura de la planta y el número de tallos (p <0.05). El resultado de la regresión gradual en la cual el rendimiento de aceite esencial se consideró como variable dependiente mostró que el% de aceite esencial y el rendimiento de MS representaron 39.95 y 47.75% de las variaciones totales en la producción de aceite esencial, respectivamente. En el análisis de factores, los valores de Eigen obtenidos de 1 a 3 factores fueron mayores que uno con 88.9% de las variaciones totales. En el primer factor, los rasgos de rendimiento de MS, altura de la planta, cobertura del dosel, número de tallos y en la segunda fecha de floración del factor, DGC y producción de aceite esencial y en el tercer factor, % de aceite esencial, tuvieron coeficientes de vectores Eigen más altos para la clasificación del genotipo. En el análisis de conglomerados, los genotipos se categorizaron en cuatro grupos. De acuerdo con los resultados obtenidos, el grupo 1 para madurez temprana, los grupos 3 para cobertura vegetal del dosel, el número de tallos, el rendimiento de MS y la producción de aceite esencial y el grupo 4, para% de aceite esencial, tuvieron valores promedio significativamente más altos que otros grupos. Hubo una buena concordancia entre los resultados obtenidos de los análisis de grupos y factores en la representación del diagrama de dispersión de 84 genotipos en función del primer y el segundo factor. Se concluyó que la población del grupo 3 es capaz de producir nuevos cultivares mejorados y debe centrarse en la selección de mayor rendimiento de biomasa aérea, altura de la planta, número de flores, % de aceite esencial, junto con la fecha de floración temprana.

Abstract In order to investigate diversity and explain the relationships of essential oil yield with morphological traits, 84 populations T. polycephalum, were sown in the field using randomized complete blocks design (RCBD) with three replicates in Research Institute of Forest and Rangeland, Tehran, Iran in 2013-2014. Data were collected for flowering date, growth degree days (GDD), stem number, plant height, dry matter (DM) yield, essential oil percentage, and essential oil yield. The relationships among traits were determined using correlation, regression and factor analysis. The genetic distance and genotype classification were determined using cluster analysis. DM yield was positively correlated with plant height, canopy cover, stem number and oil yield (p<0.01), whereas oil% was negatively correlated with plant height and stem number (p<0.05). Result of stepwise regression in which essential oil yield were considered as dependent variable showed that essential oil%, and DM yield accounted for 39.95 and 47.75%, of the total variations in essential oil production, respectively. In factor analysis, the Eigen values obtained from 1 to 3 factors were higher than one with 88.9% of total variations. In the first factor, traits of DM yield, plant height, canopy cover, stems number, and in the second factor flowering date, GDD and oil yield and in the third factor oil% had higher Eigen vector coefficients for genotype classification. In cluster analysis, genotypes were categorized in four groups. According to the obtained results, cluster 1 for early maturity, clusters 3 for plant height canopy cover, stems number, DM yield and essential oil production and cluster4, for essential oil%, had significantly higher mean values than other groups. There was a good agreement between the results obtained from cluster and factor analyses in scatter diagram representation of 84 genotypes based on the first and second factors. It was concluded that population of cluster 3 are capable to breeding improved new cultivars and should be focused on selection higher aerial biomass yield, plant height, flower number, essential oil%, coupled with early flowering date.

ABSTRACT The aim of this study was to evaluate anti-hypoxia activity of polyphenolic extracts of Crataegus microphylla and Crataegus pentaegyn on mice. Three experimental models of hypoxia were considered, including asphyctic hypoxia, haemic hypoxia, and circulatory hypoxia. Polyphenolic extract of both plants exhibited significant anti-hypoxic activity and prolonged animal survival time. Anti-hypoia activity of C. pentaegyn was found to be superior to that of C. microphylla in circulatory and asphyctic hypoxia. Antihypoxic activity of these extracts may be attributed to their phenolic compounds.

Abstract The present paper deals with free vibration of functionally graded fiber reinforced rectangular plates subjected to thermal loads. The rectangular plates are assumed orthotropic. The continuous grading fiber reinforced plates have a smooth variation in matrix volume fraction in the thickness direction. Two different types of volume fraction profiles through the thickness of plate are proposed: classic and symmetric. As the plate is thick, the equations of motion are derived based on three dimensional theory of elasticity. Inevitably, 3D General differential quadrature method is used instead of regular solving methods in order to discretize equations of motion equations as linear set of algebraic equations. The effects of temperature, volume fraction profiles, and boundary conditions are investigated. Some interesting conclusions obtained when the material properties were assumed to be temperature-dependent. It has been observed that temperature and functionality of FG plate have significant effect on the natural frequencies of the plate.

Abstract This paper investigates the effect of different parameters on stress analysis of infinite orthotropic plates with central polygonal cutout using gray wolf optimization algorithm. The important features of gray wolf algorithm include flexibility, simplicity, short solution time and ability to avoid local optimums. The effective parameters on stress distribution around cutouts include load angle, curvature radius of the corner of the cutout, cutout orientation and fiber angle for orthotropic materials. The used analytical solution is the expansion of Lekhnitskii’s solution method. The effect of the aforementioned parameters on the stress distribution around triangular, square, pentagonal and hexagonal cutout is examined. The results showed that these parameters have significant effects on stress distribution around the cutouts and the structural load-bearing capacity will increase without changing the type of material if the parameters are correctly chosen.

Con el objeto de evaluar el efecto de la temperatura baja sobre las características fenológicas de la festuca alta (Festuca arundinaceae) se recolectaron semillas de cultivares Bejnord, Esfahan, Brojen, Kamiran, Mashhad en bancos de germoplasma. Estas fueron sembradas en recipientes con temperaturas fluctuantes de 20 ± 5°C durante el día y de 5 - 12°C durante la noche. Posteriormente el semillero de 15 días de edad se cultivo a una temperatura base de 4 °C durante 30 días. Los materos fueron retornados a condiciones normales de invernadero y de campo hasta su etapa de floración. En la etapa de floración, las características morfológicas incluyeron: altura de planta, longitud de pedúnculo, longitud de panícula, número de panículas y longitud de la hoja bandera, peso fresco y seco y los pesos de la semilla, características de calidad como la digestibilidad de materia seca (DMD), proteína cruda (CP), carbohidratos solubles en agua (WSC), fibra detergente ácida (ADF) y cenizas totales, se registraron. Los resultados mostraron que las poblaciones de los cvs. Mashhad y Esfahan presentaron valores superiores para altura de la planta, longitud del pedúnculo, longitud de la panícula, peso de la semilla, peso fresco y seco con respecto a otras poblaciones. Exceptuando la población Esfahan, las otras cuatro poblaciones fueron evaluadas por su buen valor nutritivo debido al alto contenido de carbohidrato soluble en agua. Los resultados también mostraron que los días grados crecimiento (GDC) de aquellas poblaciones que estaban sujetas a temperatura fría, presentaron menor estado de floración que el tratamiento control. Se concluyó que la temperatura fría no presentó efecto alguno sobre los desarrollos vegetativos, particularmente sobre la etapa de floración, pero redujo las fechas de floración en la etapa generativa

In order to study the effect of cold temperature on morphological and quality characteristics of tall fescue (Festuca arundinaceae), seeds of five populations were provided from natural resource gene bank, Iran as: Bejnord, Esfahan, Brojen, Kamiran and Mashhad were sown on pots with condition of fluctuation temperatures at 20±5°C during day and (5-12)°C during night time in greenhouse. The base temperature (4°C) were applied on 15th days seedling age for 30 days for vernalization compare with control. The pots were return in normal conditions besides control pots in greenhouse and then outdoor. The pots were arranged using factorial experiments based on completely randomized design with three replications. The plants had grown up to their flowering and maturity stage. In flowering stage, morphological traits including: plant height, peduncle length, panicle length, flag leaf area and flag leaf length, fresh and dry weight and seed yield and quality traits as dry mater digestibility (DMD), crude protein (CP), water soluble carbohydrates (WSC), acid detergent fiber (ADF) and total ash (ASH) were recorded. Results showed that populations of Mashhad, and Brojen had higher values for fresh and dry weight than those of other populations. For plant height, peduncle length, flag leaf area the Brojen, Bojnord and Kamyaran had higher values, respectively. For quality traits, the higher values of both DMD (56.5%) and WSC (14.09%) were obtained for Esfahan and higher value of CP (18.1%) for Bojnord. Results also showed that the growth degree days (GDD) of those populations which were subjected to cold treatment was lower flowering stage than those for control. It was concluded that cold treatment had no effect on vegetative developments particularly in seedling stage, but it reduced flowering dates in generative stage and increased plant dry matter yield. It was proved that the Tall fescue is cool season grass and it needs a period of vernalization for promotion of flowering

Effect of calcium addition on microstructure, hardness value and corrosion behavior of five different Mg-xCa binary alloys (x = 0.7, 1, 2, 3, 4 wt. (%)) was investigated. Notable refinement in microstructure of the alloy occurred with increasing calcium content. In addition, more uniform distribution of Mg2Ca phase was observed in a-Mg matrix resulted in an increase in hardness value. The in-vitro corrosion examination using Kokubo simulated body fluid showed that the addition of calcium shifted the fluid pH value to a higher level similar to those found in pure commercial Mg. The high pH value amplified the formation and growth of bone-like apatite. Higher percentage of Ca resulted in needle-shaped growth of the apatite. Electrochemical measurements in the same solution revealed that increasing Ca content led to higher corrosion rates due to the formation of more cathodic Mg2Ca precipitate in the microstructure. The results therefore suggested that Mg-0.7Ca with the minimum amount of Mg2Ca is a good candidate for bio-implant applications.

El desarrollo de infraestructura subterránea, con preocupaciones ambientales y tendencias económicas, está influyendo a la sociedad. Debido a la naturaleza crecientemente crítica de las instalaciones de sistemas utilitarios, especialmente en áreas congestionadas, ha aumentado la necesidad de sistemas de monitoreo y control. Por lo tanto el sistema de microtunelación ayudará a minimizar la superficie perturbada. La selección adecuada de Máquinas Taladradoras de Microtúnel (MTBM, por sus siglas en inglés) es la decisión más juiciosa que puede hacerse, puesto que una vez que la excavación sin zanjas ha iniciado, podría ser muy tarde para hacer cambios en el equipo sin un costo ni atrasos adicionales. Luego, los diversos factores y parámetros afectan la escogencia de la máquina. En este artículo se discute una metodología desarrollada, que se basa en el Proceso Jerárquico Analítico Difuso (FACH) para determinar pesos de los criterios y subcriterios, y luego ordenarlos. En el modelo propuesto se especifican cuatro criterios de sitio, maquinaria, estructura, impacto de la fuerza laboral y 18 subcriterios. Los niveles lingüísticos de comparaciones producidos por expertos se construyen en forma de números difusos triangulares para construir matrices de comparación difusa por parejas. Por lo tanto el FAHP usa las matrices de comparación por parejas para determinar los pesos de los criterios y subcriterios

The development of underground infrastructure, environmental concerns, and economic trend is influencing society. Due to the increasingly critical nature of installations of utility systems especially in congested areas, the need for monitoring and control system has increased. The microtunneling system will therefore have to provide for possibility of minimized surface disruption. Suitable selection of Microtunneling Boring Machine (MTBM) is the most curial decision that manager must be done. Because once the trenchless excavation has started, it might be too late to make any changes in equipment without extra costs and delays. Therefore, the various factors and parameters are affecting the choice of machine. In this paper discusses a developed methodology based on Fuzzy Analytic Hierarchy Process (FAHP) in order to determine weights of the criteria and sub criteria and then ranking them. Within the proposed model, four criteria site, machinery, structural, labor force impact and 18 sub-criteria are specified. The linguistic level of comparisons produced by experts are tapped and constructed in a form of triangular fuzzy numbers in order to construct fuzzy pair wise comparison matrices. Therefore, FAHP uses the pair wise comparison matrices for determining the weights of the criteria and sub-criteria.