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Abstract: This study offers novel progresses for a semianalytical method to simulate 2D propagation of cracks based on linear elastic fracture mechanics. For this purpose, a new algorithm is proposed on the basis of the linear elastic fracture mechanics for crack propagation in single‐mode and mixed mode. Herein, discretization is only performed on the boundaries of the problem by using specific subparametric elements and higher‐order Chebyshev polynomials as mapping functions. Implementing the weighted residual method and by taking Clenshaw‐Curtis numerical quadrature, diagonal Euler's differential equations are obtained. Consequently, once the local coordinate origin is assumed at the tip of the crack, the stress intensity factors can be derived directly. In accordance with the rate of maximum energy release as a propagation criterion and by proposing a new quasi‐automatic remeshing procedure based on domain division, the crack propagation is applied here. Based on the new presented algorithm, application of the new semianalytical method to crack propagation analysis is more flexible and efficient. By taking this advantage, relatively coarse and simple discretization compared with other computational methods may be used. By modelling 4 benchmark problems with a few numbers of degrees of freedom, the validity and accuracy of the current method is illustrated. Results show that the presented algorithm is applicable for efficient and precise prediction of crack trajectories. [ABSTRACT FROM AUTHOR]

The existence of crack and notch is a considerable and serious subject in the failure study of solids and structures. As most of cracked domain problems do not have closed-form solutions, numerical methods are dominant approaches dealing with fracture mechanics problems. In fracture mechanics and failure analysis, cracked media energy and consequently stress intensity factors (SIFs) play a crucial and significant role. Based on linear elastic fracture mechanics, the SIFs may be estimated using the energy release rate, as an indirect approach. This study presents the development of a new semi-analytical method to model cracked media. In this method, only the boundaries of problems are discretized using specific higher-order subparametric elements and higher-order Chebyshev mapping functions. Implementing the weighted residual method and using Clenshaw-Curtis quadrature yield diagonal Euler's differential equations. Therefore, when the local coordinate origin is located at the crack tip, the geometry of crack problems is implemented directly without further processing. In order to present crack boundary conditions, a modified form of nodal force function is presented. Validity and accuracy of the proposed method is fully illustrated by four benchmark problems, whose results agree very well with those of other numerical and/or analytical solutions existing in the literature. [ABSTRACT FROM AUTHOR]

Background: Renal transplantation has long been considered the gold standard medical care for patients with end-stage renal disease. Candiduria continue to be a significant complication for renal transplant recipients. The risk of infections depends on the amount of immunosuppression and exposure to the potential pathogens. Objective: Molecular identification of Candida species isolated from renal transplant recipients with candiduria. Methods: Between 2009 and 2014, 62 Candida isolates were collected from 485 renal transplant recipients. All isolates were identified by PCR-RFLP profiles after digestion with the restriction enzyme MspI. Results: C. albicans (44%) and C. parapsilosis complex (5%) had the most and the least prevalence, respectively. Male to female ratio was 26/36, ranging in age from 19 to 62 years. Conclusion: Due to the fact that candiduria is connected with increased mortality in renal transplant recipients, precise identification of Candida species by molecular techniques can lead to an appropriate therapy among high risk patients. C. albicans remains the most prevalent species isolated from renal transplant recipients, Nevertheless, the number of non-C. albicans Candida species looks to be emerging. [ABSTRACT FROM AUTHOR]

This study presents a novel development of a new semi-analytical method with diagonal coefficient matrices to model crack issues. Accurate stress intensity factors based on linear elastic fracture mechanics are extracted directly from the semi-analytical method. In this method, only the boundaries of problems are discretized using specific subparametric elements and higher-order Chebyshev mapping functions. Implementing the weighted residual method and using Clenshaw-Curtis numerical integration result in diagonal Euler's differential equations. Consequently, when the local coordinates origin is located at the crack tip, the stress intensity factors can be determined directly without further processing. In order to present infinite stress at the crack tip, a new form of nodal force function is proposed. Validity and accuracy of the proposed method is fully demonstrated through four benchmark problems, which are successfully modeled using a few numbers of degrees of freedom. The numerical results agree very well with the analytical solution, experimental outcomes and the results from existing numerical methods available in the literature. [ABSTRACT FROM AUTHOR]

Open dumping is the common procedure for final disposal of municipal solid waste (MSW) in Iran. Several environmental pollution and soil degradation problems were found as a consequence of poor planning of landfills. So recognition of the MSW landfill state is required to prevent environmental problems. The objective of this research was to study the suitability of existing municipal landfill sites using geographic information system methods. Tonekabon city in the west area of Mazandaran province, northern Iran, along the southern coast of the Caspian Sea, was chosen as a case study. In order to carry out this evaluation, two guidelines were used: Minnesota Pollution Control Agency (MPCA) and regional screening guidelines. The results indicate that the landfills were not located in suitable sites and also that there are few suitable locations to install the landfills. [ABSTRACT FROM AUTHOR]

There has been some decline in the land potential capacity in many developing countries, and depending on location, the multi objective management strategy of Agroforestry can make effective use of natural resources to be feasible. Environmental principles which are effective on Agroforestry systems and their components, together with climatic factors, are the important parameters which been evaluated in this study. Two cities, Kazeroun (with warm climate) and Sepidan (with cold climate) in Fars province, were chosen for the purpose of this research, and after proper identification and classification of the Agroforestry systems, the effects of climatic factors were analyzed. Nineteen points were identified in these two cities by field investigations, with each type of Agroforestry systems and their corresponding components determined in each point. From the results, most of the systems in Kazeroun, characterized with warm climate, were Agrosilvopastoral, while Sepidan with a characteristic cold climate was the Agrosilvicultural system. Also, the components of each system clearly changed with change in climate, owing to the great importance of the livestock and crop components in Kazeroun and Sepidan, respectively. In general, it can be concluded that the impact of climatic factors on Agroforestry systems and their components has been approved in this study, and the results can be applied in developing these systems in other regions. [ABSTRACT FROM AUTHOR]

Pre-eclampsia, as one of the most critical pregnancy complications, considered as a common cause of death in the prenatal period. The placental position had no significant association with pre-eclampsia, but there was a significant association between pre-eclampsia and placental thickness, and pre-eclampsia cases had a thicker placenta than normal group (P = 0.038). Placental thickness which is easily assessed at middle trimester of pregnancy by routine screening ultrasonography, could be an ideal predictive tool for evaluating the risk of developing pre-eclampsia. [Extracted from the article]

In the railway network of Iran, a large number of masonry arch bridges exist which most of them was constructed 80 years ago. Despite these types of bridges have shown an appropriate behavior under the influence of gravity (vertical) loads, they have not been designed seismically. Concerning to the seismic hazard zoning map of Iran, most of these railway infrastructures are placed in the very high seismicity zones and constructed near the major faults. So the seismic assessment of these types of bridges has become a significant subject for the engineers to explain the failure and seismic performance levels of these structures. Thus, they can be rehabilitated or removed if it is found required. Among various methods for seismic estimation of the capacity of the structures under seismic loading, the non-linear dynamic method or the incremental dynamic analysis (IDA) may be mentioned as the most precise and complete method for near-field excitations. For this purpose, by selecting 28 near-field earthquake records, this study has seismically surveyed two railway masonry arch bridges, which are respectively placed in the kilometers 23 (2L20 bridge) and 24 (5L06 bridge) of the old railway of Tehran-Qom. The macro-modeling approach was used in the finite element method. In total, 316 non-linear dynamic analyses have been carried out for the seismic assessment of the masonry arch bridges under near-field ground motion. The results found from the IDA analysis specified that the near-field seismic performance of the masonry arch bridge with lower span length (i.e., 5L06 bridge) is safer than the bridge with longer span length (i.e., 2L20 bridge). Mostly, it has to decide to retrofit the masonry bridge with longer span length to improve their performance since the seismic behavior of those has been found inappropriate under near-field earthquakes. • FE simulation has performed to evaluated seismic response of masonry arch bridges • 316 incremental dynamic analysis (IDA) for near-field earthquakes has been conducted • The statistical analysis of the obtained results indicated that the arch bridges perfectly obey the Gamma distribution • IDA showed that the seismic behavior of these structures completely depends on their geometrical and mechanical features • The results show that the response of these infrastructures under near-field earthquakes is sensitive to velocity response [ABSTRACT FROM AUTHOR]

There is a large number of old arch bridges in Iran's railway network which the majority of them have been built more than 70 years ago. These structures, though displaying a good performance under the effect of service (gravity) loads but the seismic (lateral) loads have not been taken into account in their design; therefore, the seismic assessment of these structures is deemed necessary for obtaining their failure and seismic performance levels. So they can be strengthened or rendered out of order in case it is found necessary. There are numerous methods for evaluating the residual capacity of the structures under seismic excitation which among them the non-linear dynamic analysis or the incremental dynamic analysis (IDA) is the most accurate and perfect method. Selecting 22 far-field earthquake records, the present study investigated two plain concrete arch bridges which are located in kilometers 23 and 24 of the old Tehran-Qom railway, respectively. By using the finite element method and the macro-modeling method the km-23 and km-24 bridges were simulated and totally 231 non-linear dynamic analyses have been conducted. The results obtained from the incremental dynamic analysis indicated that the seismic behavior of the bridge with longer span length is more vulnerable (km-23) than the bridge with lower span length (km-24). Generally, the seismic performance of plain concrete arch bridges has been found inappropriate, therefore to improve their performance it is necessary to retrofit these type of structures. [ABSTRACT FROM AUTHOR]

One of the goals of the International Carbon Sequestration Project in South Khorasan Province is to study the sustainability of natural resources, especially in the rehabilitated areas, by reducing the reliance of villagers to the natural resources of the region, creating alternative livelihoods with job empowerment and solving the problems of villagers in the region, especially rural women. The purpose of this study was to predict the rural women' empowerment who received microcredits during the project. The research was done through a descriptivecorrelational method. Statistical sample includes 188 rural women who were members of the microcredit Fund. The validity of the questionnaire was confirmed by panel of research committee experts and the reliability was confirmed by calculating Cronbach's alpha coefficient to 0.95. The results of study showed that there is positively a significant correlation between rural women empowerment and variables of Membership Years, Loan Amount, and Loan adequacy, Age, Literacy Level and Income per month. But rural women empowerment could be predicted by three variables of Loan adequacy, Literacy Level and women Age. Also, Loan adequacy was known as the most powerful predictor of rural women empowerment. Given the positive impact of microcredits on rural women empowerment, as well as rural women empowerment to reduce pressure on ecosystems and improve carbon sequestration, it is proposed to increase the microcredit program and its amount. [ABSTRACT FROM AUTHOR]

This paper considers the problem of hybrid flowshop scheduling. First, we review the shortcoming of the available model in the literature. Then, four different mathematical models are developed in form of mixed integer linear programming models. A complete experiment is conducted to compare the models for performance based on the size and computational complexities. Besides the models, the paper proposes a novel hybrid particle swarm optimization algorithm equipped with an acceptance criterion and a local search heuristic. The features provide a fine balance of diversification and intensification capabilities for the algorithm. Using Taguchi method, the algorithm is fine tuned. Then, two numerical experiments are performed to evaluate the performance of the proposed algorithm with three particle swarm optimization algorithms available in the scheduling literature and one well-known iterated local search algorithm in the hybrid flowshop literature. All the results show the high performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The utilization of renewable biomass as feedstock for biofuel production has been gaining prestige to mitigate carbon emissions. This paper aims to render an optimization model for designing a resilient and reliable biomass-to-biofuel supply chain network in which multi-modal terminals, biorefineries, and their connection link could be faced with disruption. For this purpose, risk-averse optimization, transitional probabilities, and spatial statistics models are employed. What is more, to overcome the repercussions of uncertain demand and the availability of raw materials, risk pooling and M/M/1 queuing system are considered. Finally, since the proposed model is an NP-hard problem, two meta-heuristic algorithms called improved ray optimization and colliding bodies optimization are employed to solve the proposed model. Computational results reveal that by increasing 20% of the conversion rate of biomass to biofuel, which leads to increase biomass supply, biofuel production increases by 20.88%, and the SC cost declines by 9.32% due to the better capacity distribution of bio-refineries. Also, the proposed model increases by 20.87% in the total SC costs under random disruptions than the risk-neutral model, although the failure costs of SC decline by 80.45%. Image 1 • Presenting a resilient and reliable biomass-to-biofuel supply chain. • Applying conditional-value-at-risk and absolute-semi deviation to reflect risk measure. • Considering the disruptions of two types of facilities and connecting link among them. • Considering risk-pooling and congestion to mitigate demand uncertainty and seasonality effect. • The proposed framework declines the failure costs of the supply chain by 80.45%. [ABSTRACT FROM AUTHOR]

Objective: an appropriate psychological intervention to promote the level of the public health and mental well-being of nurses has a great importance. This investigation was aimed to study the effectiveness of stress management training on the psychological welfare of nurses in Imam Khomeini Hospital. Methodology: this study was quasi-experimental with pretest-posttest that used a control group. Hence, 40 of the nurses in Imam Khomeini Hospital were selected by using a convenience sampling method and placed in the experimental group and the control group. Both groups were pretested by using psychological well-being 84-question scale. Afterwards, the experimental group was trained for ten sessions under stress management skill exercise, and the check group got no intervention. Next, both societies were post-tested, and the acquired data were analyzed by using inferential and descriptive statistical methods accompanied by SPSS 21 software. Findings: the results indicated that stress management training significantly led to the promotion of psychological well-being in nurses (p < 0.001). Conclusion: it was found from the research that due to the high level of effectiveness of stress management training, its low cost, and its high acceptability by the patients, especially when it was performed in a group, had a significant positive impact on the promotion of psychological well-being in nurses. [ABSTRACT FROM AUTHOR]

In this study, 54 five-year-old farmed female beluga at stage II of sexual maturation were treated with 0 (control), 0.2, 0.4, 0.8 and 1.6 g of dietary soy equol (EQ) and genistein (GE) per each kilogram (kg) of diet during a year. Blood samples were collected and ovarian biopsy was performed quarterly. Results showed that 64.4% of the Huso huso sexually matured at EQ 0.4 g/kg and reached stage IV of sexual maturation. Oocytes diameters increased significantly at all concentrations of EQ and 0.2, 0.4 and 0.8 concentrations of GE and reached a maximum (3 ± 0.2 mm) at 0.4 g/kg EQ concentration at the end of experiment (P<0.05). Blood plasma testosterone (T) level was 0.3 ± 0.06 ng/ml at the beginning and reached a maximum (21.04 ± 1.91 ng/ml) at EQ 0.4 g/kg at the end of the experiment (P<0.05). 17β-estradiol (E2) levels increased significantly at some concentrations of GE and EQ at the end as compared to the beginning, reaching a maximum (12.6 ± 1.04 ng/ml) at EQ 0.4 g/kg at the end of the experiment (P<0.05). 17αhydroxy progesterone (17α-OHP) levels showed no significant difference (P>0.05). In conclusion, EQ at a 0.4 g/kg concentration showed more powerful positive reproductive effects than other concentrations of EQ and GE in farmed female H. huso. Comparatively, EQ showed more estrogenic effects on ovary development in comparison to GE concentrations. Its use is therefore suggested as an additive to diets to induce ovary development in Huso huso. [ABSTRACT FROM AUTHOR]

Background: Brain-dead patients are not salvageable. While the number of patients in need of organ transplantation is increasing, the shortage of organ donors remains significant. Objective: To determine the knowledge and attitudes of Bojnurd citizens towards brain-dead and organ donation. Methods: In this cross-sectional study, conducted in August 2015,122 emergency and intensive care nurses of Bojnurd's hospitals were selected through a convenient sampling method. The tool used, was a self-completeing questionnaire consisting of three parts; it was validated by content validity method; its reliability was determined by Chronbach's α. Results: 65 of studied nurses were female. The mean±SD age of participants was 31.1±6.5 years. The mean±SD knowledge and attitude scores were 14.4±2.4 and 52.1±6.1, respectively. There were not significant differences between males and females in terms of knowledge and attitude scores. Conclusion: The knowledge of nurses was good and the attitude was in moderate level. With regard to the important role of nurses in caring of patients' family member, it has been suggested that some necessities should be provided for transferring this knowledge to brain death patient's families. [ABSTRACT FROM AUTHOR]