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The increased number of pedestrian injuries and fatal deaths are resulting from road accidents due to the increased urban population and number of private vehicles. In order to address this issue along with other safety measurements, design, and material of engine hood has been a key point for an automotive industry. The most common materials for the manufacturing of engine hood were steel, aluminum and recently, composite materials have been used due to its added advantage for pedestrian safety. In this study, the finite element models of the pedestrian head impact on automotive hood, adult headform, composite laminate plate and sandwich composite plate were created by ABAQUS/Explicit. Simulation results are validated by Euro-NCAP pedestrian head to hood impact tests. The results show that the FEM modeling of the composite laminate plate, sandwich composite plate and engine hood can effectively predict the pedestrian head injury and deformation pattern of the models. This method can be an applicable tool for the vehicle, pedestrian safety evaluation and related development. [ABSTRACT FROM AUTHOR]

Ischemic heart diseases are the most common cause of death worldwide, Prehospital delay associated with increased mortality and poorer outcome. This study aimed to determine whether particular patient's characteristics are associated with delays in seeking care, it also determined the impact of the delay on in-hospital outcomes, 30 days' outcomes, and the cardiac functional status for patients after 30 days of their disease. This prospective 30 days' cohort study was conducted in Al shaab tertiary hospital in Khartoum. All patients diagnosed with myocardial infarction from 13th of January to 13th of February 2021 were included. Sociodemographic, clinical features, and health seeking behavior were collected using structured questionnaire, Patients were followed up by telephone to collect in-hospital and 30 days' outcomes data. The Duke Activity Status Index (DASI) was used to assess the cardiac functional status after 30 days; Wilcoxon rank-sum test, Chi-square test of independence and Fisher's exact test were used to find if there is difference between groups categorized according to pre-hospital delay to tertiary hospital (< 6 hours or ≥ 6 hours), and to find the difference in the prognosis of patients according to pre-hospital delay time to hospital. 98 patients were enrolled. The mean age for the participants was (58.6 ± 10.3) years. The mean total pre-hospital delay time was (11.0 ± 6.3) hours and the mean time patients took to decide that their condition requires medical attention was (5.6 ± 5.9) hours. The mean time for first medical interactions patients had was (6.9 ± 6.0) hours. Patients misperception of symptoms significantly contributed to prolonged pre-hospital times (p=0.002). Prolonged referral time led to prolonged prehospital time as the mean time for making the referrals was (2.7 ± 3.1) hours (p=0.005). STEMI patients tended to have earlier first medical interactions than patients diagnosed with Non-STEMI. Hypertensive patients had prolonged first medical interactions (p=0.016). In addition, prolonged time to first medical interaction led to a significant decrease in the cardiac functional status index after 30 days of admission as measured by the Duke Activity Status Index (DASI). Some modifiable factors contribute to longer pre-hospital delay of myocardial infarction patients, resulting in decreased cardiac functional status after one month, patient's awareness about cardiovascular disease and improved referral pathway of the existing health care system may reduce the delay. [ABSTRACT FROM AUTHOR]

• Tensile strength depends on strain rates, temperatures, and coupling effects. • FRP composites are temperature sensitive due to the resin's softening. • FRP composites highly depend on reinforcement and resin properties. • Fiber breakage and fiber pullout become dominant at low and high strain rates, respectively. The fiber-reinforced polymer (FRP) composites are currently widely used in infrastructure construction, and the study on the dynamic performance and temperature sensitivity is still under investigation. Understanding the effects of strain rate and temperature on the tensile behaviour of FRP composites is vital to design the composite structures under harsh conditions (earthquake, explosion, or impact). Therefore, this study comprehensively reviews tensile performance of FRP composites under several strain rates (quasi-static, low, intermediate, and high) and temperatures. The tensile strength of FRP composites depends on the strain rates, temperatures, and coupling effect. The failure patterns of FRP materials are also reviewed at different strain rates and temperatures and found that fiber cracking and fiber pullout become dominant at low and high strain rates, respectively, which can help gain insight into failure mechanisums of FRP composites. [ABSTRACT FROM AUTHOR]

• Replacing the ordinary materials with the SW and SS can reduce the workability. • Exposure to the alkaline is the main threat to the long-term performance of SWSSC. • The deformed surface enhancement of the FRP bars can enhance its bond performance. • The durability of FRP-SWSSC can be affected by the type of FRP materials. • The increased elevated temperature lead to severer degradation of the FRP-SWSSC. FRP reinforced seawater sea sand concrete (FRP-SWSSC) combines the advantages of corrosion-free FRP bars in the marine environment and the direct utilization of seawater and sea sand, which can lead to a more sustainable and economic-efficient construction material. This paper reports a comprehensive overview of the current works on workability, mechanical properties (tensile, interlaminar shear, transverse shear, and flexural strength), bond behavior, durability, and applications of FRP-SWSSCs. The results indicated that exposure to the saline/alkaline environment is the main threat to the long-term performance of SWSSC. Furthermore, durability performance can also be affected by the type of FRP, surface protection, and concrete. Normally, the surface enhancement of the FRP bars can enhance its durability performance under saline environment. The current study mainly focuses on the application of glass fiber reinforced polymer (GFRP) in SWSSC, while the basalt fiber reinforced polymer (BFRP) bars have gained less attention. Also, GFRP demonstrated better resistance to both simulated concrete pore solution and saline condition than BFRP. Also, the exposure test under real conditions is essential to validate the results obtained from experiments in the simulated environment. The future research directions on FRP-SWSSC systems are recommended based on the summarization of current studies and field application. [ABSTRACT FROM AUTHOR]

In-vehicle to pedestrian collisions, the main reason for fatal injuries is the pedestrian to vehicle impacts, which are caused by the direct impact of the pedestrian head to the front part of the automotive hood during a collision. This paper deals with the development of a new finite element model to simulate the car-to-pedestrian front impacts between the adult headform and vehicle hood composite structures according to the EURO-NCAP requirements. The pedestrian head impacted by selected three points over the outer structure of the hood with three different inclination angles. The HIC values for engine hood structure with different stacking sequences: [[0, 90, 45, −45] 2 , 0, 90] S , [0, 90] 10 and [[0, 90, 45, −45] 2 , [0, 90] 6 at 6°, 8° and 10° inclination angles have been investigated and discussed. The effects of the inclination angles to HIC value, displacement, and absorbed energy of the vehicle hood composite structures have been investigated and compared. The results show that for all the stacking sequences of the hood structures at (A) head impact point, HIC values found to be less than 2000. Which, means all the structures at this point with different inclination angles satisfied the requirements of pedestrian safety. The energy-absorbing found to be higher in (A) head impact point for all the stacking sequences due to the engine hood stiffness variation at this point is different compared with other points (B and C). This model can be an appropriate tool for the car-to-pedestrian front impacts evaluation and related development on the composite structure of the hood with different inclination angles. • A new finite element model to simulate the car-to-pedestrian front impacts was applied. • The HIC values for engine hood structure with different stacking sequences at 6°, 8°, and 10° inclination angles have been studied. • The effects of the inclination angles of the vehicle hood composite structures have been investigated. • For all the stacking sequences of the bonnet structures at (A) head impact point, HIC values found to be less than 2000. • Increasing displacement can lead to less HIC. However, more displacement may is not recommended. [ABSTRACT FROM AUTHOR]