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The rapid increase in vehicle numbers, traffic speed, and axle loads has considerably shortened pavement lifespan and escalated maintenance costs. To address these challenges, modifying asphalt binders with nanomaterials and polymers has become essential for enhancing pavement durability and performance. In this study, an extensive experimental program was conducted to evaluate the effects of inorganic nanomaterials; nano-silica (NS) and nano-hydrated lime (NHL) and polymer modifiers (elastomeric SBS and plastomeric EVA) at varying dosages (2 %, 4 %, and 6 % by weight of asphalt binder) on asphalt binder properties. The investigation included conventional physical properties, high-temperature performance grading (PG), Multiple Stress Creep Recovery (MSCR), and Linear Amplitude Sweep (LAS) tests. Additionally, Scanning Electron Microscopy (SEM) was employed to assess the microstructural characteristics of modified binders. To statistically validate the findings, ANOVA analysis was performed to determine the significance of each modifier on the tested properties. The results demonstrated that SBS-modified binders exhibited superior rutting and fatigue resistance, with 6 % SBS being the most effective for high-temperature performance and 4 % SBS providing optimal fatigue life. Nanomaterial modifications also improved binder stiffness and high-temperature stability, with NHL performing better than NS. However, EVA showed limited enhancement in rutting and fatigue resistance. Overall, the findings confirm that polymer modification, particularly with SBS, is the most effective approach for improving asphalt binder performance under varying traffic and environmental conditions.

Background Leptospirosis is considered as the most common zoonosis in the world. Leptospirosis has a multiorgan affection that can affect nearly any organ in a classical, rare or unusual presentation and complications. This may include hepatic, renal, pulmonary, meninges and cardiac affections. Aim The purposes of this study were estimating leptospiral infection prevalence among people living in Shabramant village at El-Giza Governorate and identifying associated environmental and behavioral risk factors for the infection. Patients and methods This study was designed to be a cross-sectional study conducted during the period from June 2013 to May 2014. Our study included 100 participants based on history taking and laboratory investigations; a structured questionnaire was administered to collect information on individuals’ potential risk factors for leptospiral infection. Microagglutination test was performed using five Leptospira serovars: Leptospira int. icterohaemorrhagiae, Leptospira int. canicola, Leptospira int. pomona, Leptospira int. grippotyphosa and Leptospira int. wolffi to determine the presence of leptospiral antibodies and their titers in the sera of investigated patients. Results Our study found leptospirosis disease to be common among studied cases (44%), and L. icterohemorrhagiae was the only serovar detected among the studied cases. Middle-aged female patients were predominantly affected (52.6%); hence, age and sex can be regarded as risk factors of leptospirosis. Coinfections by other pathogens were also noted in this study; 22.2% of the 44 cases included had positivity for hepatitis C virus antibodies, which can be regarded as a risk factor for acquiring this disease. Also, living close to places inhabited by rodents and animals was considered as an important risk factor for exposure to such infections, and measures should be developed to minimize exposure to these animals. Conclusion It can be concluded that leptospirosis is an important neglected zoonotic disease despite its high prevalence. We recommend adding Leptospira infection to the list of possible diseases among febrile patients and increasing the awareness of the fever hospital clinicians about leptospirosis.