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Today, the lack of practical research is one of the most important concerns worldwide, and location, which is an important issue in most projects, has received less attention from experts. In this study, the location criteria of emergency escape ramps were examined, and according to the Myers formula, the temperature-distance diagram along the route was obtained. Also, the speed of vehicles entering the escape ramp was examined according to the American Association of State Highway and Transportation Officials (AASHTO) in the proposed options that were obtained from the experts. Then, 3 general criteria and 16 subcriteria were classified, and finally, the importance of criteria was examined by the fuzzy analytic hierarchy process (F-AHP), and the high-priority options were illustrated using the fuzzy technique for order performance by similarity to ideal solution (F-TOPSIS). The proposed options were evaluated and prioritized for an emergency escape ramp on the two-lane rural highways of Salavat Abad village pass of Sanandaj city, Kurdistan Province, Iran. The results showed that the technical criteria with more than 69% among the general criteria and subcriteria of the percentage of longitudinal slope, longitudinal slope length, and vehicle design speed were the most important factors influencing the location of an emergency escape ramp. Moreover, among the proposed options, the four options 3, 4, 5, and 6 had the highest score, and option 6 (Kurkur turn (2)) was identified as the most priority location for implementing the emergency escape ramp.

Improving the performance of railways depends on increasing their efficiency and the speed of locomotives, which is provided by improving the infrastructure of railways. Therefore, in various studies, researchers seek to modify ballast materials, sleepers and rails, or to study various geometric and environmental conditions in order to reduce the existing weaknesses of railways. Therefore, in order to evaluate the above conditions, various tests should be performed on railways. Some of the tests take place in the field when the train is passing. However, these tests have various limitations and endanger the safety of researchers and are associated with difficulties. Therefore, many tests are performed using various apparatuses on a laboratory scale. In this study, by reviewing different apparatuses used by researchers to simulate loading on the railway, they were compared and by examining different criteria such as loading type, different loading directions, scale of apparatuses, static and dynamic simulated loads and other environmental and geometric conditions, the best apparatuses on a laboratory scale are recommended for simulating vertical, longitudinal and lateral loads and measuring noise and vibration. By the use of TOPSIS analysis on 16 introduced apparatuses from reviewing different studies, it was found that the scaled railway track model had the first rank among different apparatuses and by modifying the weaknesses of this apparatus, it can be turned into the most comprehensive laboratory apparatus to simulate the loading of railway tracks with a scale of 1 : 5. Among the introduced apparatuses, wheel on roller test rig and roller rig had the second and third ranks, respectively, the apparatuses of which usually have a scale of 1 : 5 and deal with the interaction between the rail and the wheel and the impact of the vehicle on the railway track.

Most road design standards recommend using a spiral curve for transitions. The main advantages of using this curve are the gradual increase in the centrifugal force, creating a suitable space for presenting superelevation, and providing a correct perception of the curve for the driver. In this research, vehicle dynamic simulation software CarSim and TruckSim is used to assess the forces imposed on the vehicles. In this regard, 360 scenarios are considered for sedans, SUVs, and trucks, which consist of variations of the road geometry (simple or spiral horizontal curve), curve radius, and type and speed of the vehicle. In addition, the regression analysis is performed to examine the relationships between the lateral acceleration (as a dependent variable) and the vehicle speed, curve radius, and vehicle type (as independent variables). The results indicate that in all cases, safety in the spiral horizontal curve is greater than that in the simple horizontal curve, and the maximum side friction factor, lateral acceleration, roll rate, roll angle, yaw rate, and lateral distance in the simple horizontal curve are higher than those in the spiral horizontal curve. Moreover, the difference percentage of the side friction factor, lateral acceleration, yaw rate, and lateral distance between the simple and spiral horizontal curves is the highest in SUVs, followed by sedans and trucks, while the difference percentage of the roll rate and roll angle is the highest in sedans, followed by SUVs and trucks. The results of regression analysis illustrate that the coefficient of determination (R2) in the proposed model is 0.972, 0.964, and 0.981 for sedans, SUVs, and trucks, respectively, indicating the strong relationships between the dependent and the explanatory variables as well as the capability of the model to cover the data.

Stone matrix asphalt (SMA) mixtures are one of the most resistant types of asphalt mixtures known to date that the bulk load is borne by the aggregate skeleton. In this research, the effect of crumb rubber powder (CRP), Vestenamer polymer, and warm additives, including Sasobit, ZycoTherm, and a porous and warm mix asphalt (PAWMA), was investigated on the moisture resistance of SMA mixtures. A segregation test was performed to determine the tendency of the polymer to separate from modified polymer bitumen under storage conditions. Also, a drain down sensitivity test was conducted to explore the bleeding phenomena and drain down of SMA mixtures. Finally, a boiling water test, as well as an indirect tensile strength (ITS) test, was applied to examine the sensitivity of mixtures to moisture. The segregation test results indicated that by the use of Vestenamer polymer, a conventional (low speed) mixer can be used instead of using a high-speed mixer, and this will be very important in the cost of rubber bitumen production. The drain down test results showed that cellulose fibers prevented the bitumen bleeding of SMA mixtures. Also, the results of the boiling water test indicated that CRP samples containing ZycoTherm had the highest moisture resistance compared to the other warm additives. Among various mixtures, 8% CRP-modified samples containing ZycoTherm resulted in the lowest amount of stripping in SMA mixtures, even more than the base sample. The ITS test results illustrated that the use of CRP, Vestenamer polymer, and warm additives had a significant effect on the ITS amounts of mixtures. Moreover, the samples containing ZycoTherm had the highest tensile strength ratio (TSR) compared to the other SMA samples.

Moisture sensitivity of asphalt mixtures may cause damage due to cohesion in asphalt binder membrane and adhesion between aggregate and asphalt binder that result in considerable damage to the pavements. Therefore, by determining the adhesion quality in a modified aggregate-asphalt binder system, one can choose the suitable material compositions to decrease the moisture sensitivity of mixtures. In this study, the effects of modified asphalt binder with carbon nanofiber and modified aggregates with carbon nanotube on the moisture sensitivity of asphalt mixtures were simultaneously explored. For investigating the moisture sensitivity, the indirect tensile strength test and surface free energy concept were implemented. The results of the indirect tensile strength test revealed that modification of asphalt binder and aggregates with carbon nanofiber and carbon nanotube, respectively, increased the indirect tensile strength and tensile strength ratio values of mixtures. The results of surface free energy indicated that using carbon nanofiber and carbon nanotube enhanced the adhesion free energy of the aggregate-asphalt binder system. Moreover, utilizing carbon nanofiber to modify asphalt binder enhanced the cohesion free energy values in the asphalt binder membrane. Also, carbon nanofiber and carbon nanotube brought detachment energy of the system toward zero, indicating less desire for the mixtures to be stripped. Generally, investigations performed by the two methods showed that covering aggregates by carbon nanotube as well as utilizing carbon nanofiber as an asphalt binder modifier had a positive impact on decreasing moisture sensitivity of asphalt mixtures.

Moisture damage is known to be a key factor influencing the durability of asphalt pavements. This phenomenon will reduce the mechanical properties of asphalt mixtures due to its destructive effects on the adhesion of the bitumen-aggregate system and the cohesion of the bitumen membrane. The mineral properties of the aggregates of asphalt mixtures are one of the factors affecting moisture susceptibility. Therefore, the surface free energy (SFE) method, as one of the thermodynamic methods, and indirect tensile strength test (ITST) have been used to determine the failure mechanism and the rate of change of adhesion properties of asphalt mixtures under the influence of mineralogical characteristics. Prior to the above tests, an X-ray fluorescence spectrometry (XRF) test was performed to identify aggregate-forming minerals in eight different types of aggregates with various minerals from eight mines, and also the apparent bitumen film thickness was measured. XRF test results showed that most parts of the aggregates in mines 1– 6 were composed of SiO2, which had strong acidic properties, according to the SFE results. ITST results showed that samples constructed with aggregates of mine 7 and 8 (with high CaO mineral content) experienced a higher TSR than other mixtures in all freeze-thaw (F-T) cycles. Results of the SFE method showed that aggregates with more calcareous properties had a smaller acidic component and a larger basic component. In mines 7 and 8, where the nonpolar component of their aggregates was larger, the tendency of the aggregates to adherence and wettability by water decreased. The adhesion free energy (AFE) between bitumen and aggregates with higher CaO and less SiO2 amounts was more than AFE between bitumen and aggregates with lower CaO and higher SiO2 amounts, in dry conditions. The presence of higher amounts of CaO in aggregates increased AFE of bitumen-aggregate in presence of water from a negative value to zero. In linear regression analysis, due to the positive regression coefficient of the CaO mineral, this mineral had a positive impact on TSR; on the other hand, due to the negative regression coefficient of the SiO2 mineral, this mineral had a negative impact on the TSR of asphalt mixtures.

The construction of suitable roads in rainy areas has created problems in the construction process due to the low resistance of asphalt to moisture. To solve this problem, materials are commonly used that make mixtures resistant to moisture; however, these materials may reduce the dynamic resistance of asphalt. Therefore, materials should be used that, in addition to increasing the dynamic resistance, also increase the moisture resistance of asphalt mixtures. One of these materials used in this research is steel wool fiber (SWF), which in addition to creating conductive roads also could have a significant effect on moisture resistance. In this study, the impact of 2%, 4%, 6%, 8%, and 10% SWF on the Marshall stability and moisture sensitivity of mixtures was investigated using the Marshall stability and indirect tensile strength (ITS) tests, respectively. Moreover, using SWF as a conductive fiber, the conductivity properties of asphalt mixtures were explored to find the optimal amount of electrical conductivity. The results of the Marshall stability test indicated that by increasing SWF contents, the stability of mixtures increased, compared with the base sample, and greater amounts of 6% SWF resulted in the reduction of the Marshall stability. The results of ITS showed that modification of bitumen by SWF increased ITS and tensile strength ratio (TSR) amounts of mixtures. 6% SWF was the optimal amount for enhancing the resistance of asphalt mixtures to moisture sensitivity. The results of the electrical resistivity test showed that the resistivity had three phases: high resistivity, transit, and low resistivity. Mixtures containing less than 4% SWF illustrated an insulating behavior, with electrical resistivity greater than 7.62 × 108 Ω.m. At the transit phase, the resistivity of mixtures had a sharp reduction from 7.62 × 108 Ω.m to 6.17 × 104 Ω.m. Finally, 8% SWF was known as the optimal content for the electrical conductivity of mixtures.

AbstractBackground:Some reports show that the prevalence of metabolic syndrome is higher in poorly educated women. In our opinion, one probable reason for this is that these women experience more stressful events in their lives. We investigated the association between major stressful life events and the prevalence of metabolic syndrome and the effect of education on this relationship in women.Methods:This cross-sectional study included 35- to 55-year-old women who were first-degree relatives of type 2 diabetics. They were questioned about stressful events in their lives, their physical activities, and basic characteristics. In addition waist circumference, blood pressure, fasting blood sugar, triglyceride, total and high-density lipoprotein cholesterol (HDL-C) were measured. Metabolic syndrome was defined according to Adult Treatment Panel III (ATP III) criteria, and the number of stresses was compared between two groups of participants with and without metabolic syndrome.Results:Among the 351 study participants, the prevalence of metabolic syndrome was 28.9%. The mean number of stresses in the metabolic syndrome group was higher than in the nonmetabolic syndrome group at 3.82 ± 2.67 and 3.14 ± 2.35, respectively (P= 0.036). The prevalence of metabolic syndrome in subjects with eight or more stressful life events (46%) was greater compared to those who had experienced less than eight stresses (23.4%; P= 0.017). The relationship between stressful life events and the prevalence of metabolic syndrome was independent of the low level of education, but the prevalence of poorly educated women was associated with the number of stresses.Conclusion:Considering the probable association between stress and prevalence of metabolic syndrome, which itself increases the risk of cardiovascular diseases, educating high-risk people to cope with stresses may be beneficial in reducing the incidence of cardiovascular diseases and preventing the onset of metabolic syndrome. [ABSTRACT FROM AUTHOR]

Purpose - The paper aims to discuss the design, fabrication, communication, testing, and simulation of a new tactile probe called Elastirob used to measure the modulus of elasticity of biological soft tissues and soft materials. Design/methodology/approach - Both finite element modeling and experimental approaches were used in this analysis. Elastirob, with the ability to apply different rates of strain on testing specimens, is accompanied by a tactile display called TacPlay. This display is a custom-designed user-friendly interface and is able to evaluate the elasticity in each part of the stress-strain curve. Findings - A new device is being constructed that can measure the modulus of elasticity of a sensed object. The results of Elastirob applied on two specimens are reported and compared by the results of experiments obtained by an industrial testing machine. Acceptable validations of Elastirob were achieved from the comparisons. Research limitations/implications - The designed system can be miniaturized to be used in minimally invasive surgeries in the future. Practical implications - Elastirob determines the elasticity by drawing the stress-strain curve and then calculating its slope. The combination of the force sensing resistor, microcontroller and stepper motor provides Elastirob with the ability to apply different rates of strain on testing specimens. Originality/value - It can be employed in both in vivo and in vitro tests for measuring stiffness of touch objects. For the first time, a device has been designed and tested which is a few orders of magnitude smaller than its industrial counterparts and has considerably lower weight. [ABSTRACT FROM AUTHOR]

In this article a novel small microstrip monopole antenna with balloon-shape radiation patch and two circular ground structure in the back plane with variable band-notch structure is presented.Impedance bandwidth of the proposed antenna is approximately 153% with S11 <−10 dB in the frequency range of 3.2-23 GHz over an ultra-wideband frequency range with a variable center frequency band-notch from 5.1 GHz to 8.2 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:12-14, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27255 [ABSTRACT FROM AUTHOR]

Leishmaniasis, as a tropical and subtropical disease, is endemic in more than 90 countries around the world. Today, cutaneous leishmaniasis (CL) that affects more than 1.5 million people per year lacks a definitive treatment approach. Imatinib is an anticancer drug that inhibits the abnormal function of Bcr-Abl due to its tyrosine kinase inhibitor, and that was the reason why the drug was tested for CL treatment because protein kinases are essential enzymes in the Leishmania genus. In this study, the L. major CL model of Balb/c mice was produced by injection of the cultured metacyclic form of parasite at the base of the tail. The possible recovery of CL ulcers and determination of the optimum dose of imatinib against Leishmania amastigotes were evaluated. A significant decrease was observed in mice treated with amphotericin B (positive control group) as well as imatinib 50 mg/kg compared to the unreceived drug, negative control group (P

Over the past four decades, management plan based on the Boolean Ecological Capability model has caused major problems in the management of the Hyrcanian Forests. The aim of this study is to evaluate ecological capability of five proposed sites including Golestan National Park, Afra Takhteh Yew Forest, Kojoor Forest, Cypress Woodland of Hassanabad-e Chalous, Lomer forest along the Hyrcanian region from east to west, using both Boolean and fuzzy logic and to compare these two models. A total of 10 important factors including slope, aspect, elevation, soil types, soil erosion, soil transformation, canopy cover, the value of species, distance to streams and climate were investigated in this study. The results show that elevation, slope and aspect have the most important role in the classification of the studied area. The results of model validation with field data indicate that the fuzzy gamma model shows the better assessment, accuracy and reliability compared to the Boolean model. Based on the obtained results we suggest the fuzzy-based operation model in sustainable protection planning in the Hyrcanian Forests.