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This study investigates the effects of fiber type, resin type, and stacking sequence on the dynamic response of fiber-reinforced polymer composite (FRPC) laminates under low-velocity impact (LVI) tests. Novel thermoplastic (TP) laminates are fabricated with a newly developed liquid methyl methacrylate thermoplastic resin, Elium® 188, at room temperature. FRPCs comprising woven ultra-high molecular weight polyethylene (UHMWPE) fabrics, woven carbon fabrics, and two different hybrid systems with alternative stacking sequences of those fibers are fabricated by the vacuum-assisted resin infusion (VARI) method. Besides, equivalent thermosetting-based (TS) composites with two epoxy systems are fabricated to compare the role of matrix type. Impact tests at different energy levels are performed on the TP and TS laminates to investigate the impact characteristics, namely contact force, deflection, energy attributes, structural integrity, and failure/damage modes. Besides, the mechanics of structure genome (MSG) and the commercial finite element code ABAQUS are used to verify the experimental results for one of the developed laminates. The results demonstrate that the hybrid system with UHMWPE fibers on the sides exhibits lower structural loss up to 47% and lower absorbed energy by 18% compared to those presented by the other type of hybrid system comprising carbon fabrics on the sides. Besides, it is found that the newly developed TP laminate underwent extended plasticity and presented a ductile behavior. The newly developed TP laminate demonstrated lower structural loss up to 200%, lower contact force by 14%, and lower absorbed energy by 48% compared to those of TS counterparts.

This study investigates the effects of fiber type, resin type, and stacking sequence on the dynamic response of fiber-reinforced polymer composite (FRPC) laminates under low-velocity impact (LVI) tests. Novel thermoplastic (TP) laminates are fabricated with a newly developed liquid methyl methacrylate thermoplastic resin, Elium® 188, at room temperature. FRPCs comprising woven ultra-high molecular weight polyethylene (UHMWPE) fabrics, woven carbon fabrics, and two different hybrid systems with alternative stacking sequences of those fibers are fabricated by the vacuum-assisted resin infusion (VARI) method. Besides, equivalent thermosetting-based (TS) composites with two epoxy systems are fabricated to compare the role of matrix type. Impact tests at different energy levels are performed on the TP and TS laminates to investigate the impact characteristics, namely contact force, deflection, energy attributes, structural integrity, and failure/damage modes. Besides, the mechanics of structure genome (MSG) and the commercial finite element code ABAQUS are used to verify the experimental results for one of the developed laminates. The results demonstrate that the hybrid system with UHMWPE fibers on the sides exhibits lower structural loss up to 47% and lower absorbed energy by 18% compared to those presented by the other type of hybrid system comprising carbon fabrics on the sides. Besides, it is found that the newly developed TP laminate underwent extended plasticity and presented a ductile behavior. The newly developed TP laminate demonstrated lower structural loss up to 200%, lower contact force by 14%, and lower absorbed energy by 48% compared to those of TS counterparts.

Background The most common gender-specific malignancies are cancers of the breast and the prostate. In developing countries, cancer screening of all at risk is impractical because of healthcare resource limitations. Thus, determining high-risk areas might be an important first screening step. This study explores incidence patterns of potential high-risk clusters of breast and prostate cancers in southern Iran. Methods This cross-sectional study was conducted in the province of Kerman, South Iran. Patient data were aggregated at the county and district levels calculating the incidence rate per 100,000 people both for cancers of the breast and the prostate. We used the natural-break classification with five classes to produce descriptive maps. A spatial clustering analysis (Anselin Local Moran’s I) was used to identify potential clusters and outliers in the pattern of these cancers from 2014 to 2017. Results There were 1350 breast cancer patients (including, 42 male cases) and 478 prostate cancer patients in the province of Kerman, Iran during the study period. After 45 years of age, the number of men with diagnosed prostate cancer increased similarly to that of breast cancer for women after 25 years of age. The age-standardised incidence rate of breast cancer for women showed an increase from 29.93 to 32.27 cases per 100,000 people and that of prostate cancer from 13.93 to 15.47 cases per 100,000 during 2014–2017. Cluster analysis at the county level identified high-high clusters of breast cancer in the north-western part of the province for all years studied, but the analysis at the district level showed high-high clusters for only two of the years. With regard to prostate cancer, cluster analysis at the county and district levels identified high-high clusters in this area of the province for two of the study years. Conclusions North-western Kerman had a significantly higher incidence rate of both breast and prostate cancer than the average, which should help in des

Introduction: Emergency medical events are not randomly distributed over a certain area. Many hidden patterns may influence this distribution due to several socioeconomic, demographic, and geospatial factors. Identifying these patterns will help health policy makers have a better planning for emergency medical services (EMS) in finding high-risk places, and people at high risk. Methods: Mashhad city EMS calls records have been analyzed retrospectively. The privacy of the data was considered by eliminating the identification information such as the name or phone number of the patients. To recognize the location of the requests all the recorded addresses were mapped into a single number representing the municipality region of the address. To express the relationship between the predictors, correlation coefficient has been employed.   Results: 154528 calls in a citywide registry from March 21, 2013, to March 20, 2014, were investigated. The average of age was 42.43 years (S.D = 21.7) with 50.5% male, 40.7% female and 8.8% of the sex were not registered. 64% of the calls were medical related and the remaining 36% were trauma-related requests. Aside from traffic accident that was the top most in all regions, other top five reasons for ambulance request including weakness, seizure, unconsciousness, nervous stress, and dyspnea were recognized. Although the regions with lower socioeconomic status are more vulnerable, they request ambulances less frequently than the regions with higher socioeconomic status. Conclusion: There is a relationship between the socioeconomic status of people and their calls to EMS. The results of this study can help policymakers in finding people in potentially high-risk locations and provide facilities to reduce mortality and morbidity.

The Ru-grafted zeolite beta was found to be an excellent heterogeneous catalyst for one-pot synthesis of biscoumarins. This reaction was carried out under reflux condition and ultrasonic irradiation. On the other hand, the catalyst could be recovered for the subsequent reactions and reused without appreciable loss of activity.

The Ru-grafted zeolite beta was found to be an excellent heterogeneous catalyst for one-pot synthesis of biscoumarins. This reaction was carried out under reflux condition and ultrasonic irradiation. On the other hand, the catalyst could be recovered for the subsequent reactions and reused without appreciable loss of activity.