Enhancing clayey soil performance with lime and waste rubber tyre powder: Mechanical, microstructural, and statistical analysis.

Nowadays, for soil stabilisation and cleaner production of geo-composites, the possibility of utilizing waste rubber is in vogue. The present paper deals with experimentally investigating the mechanical and micro-structural characteristics of weak Indian clayey soil partially substituted with lime (0-3.5%) and waste rubber tyre powder (0-15%). It was observed that, with increasing lime and rubber powder content, the plasticity index of the soil decreases. The shear strength and compaction testing results reveal that adding lime and rubber tyre powder (RTP) enhances the geotechnical performance of clayey soil up to an optimum dosage value. Also, the tri-axial shear testing was performed to obtain stress-strain curves for all considered soil mixes. For modified clayey soil containing 3% lime and 12.5% rubber powder, the cohesion values and bearing capacities improved phenomenally by 36.1% and 88.6% respectively, when compared to clayey soil. Further for this mix, SEM analysis reveals a compacted microstructure which improves dry-density and California's bearing ratio among all modified mixes. The novel co-relations upon regression analysis are found able to predict plasticity index, dry density, bearing capacity and shear strength with higher confidence levels. Overall, the cost-benefit analysis worked out to obtain the optimum cost of construction of footings and flexible pavement shows cost deductions up to 19% and 39% respectively while utilizing modified clay soil mixes containing 3% lime and 12.5% rubber powder in subgrade, ultimately making production stronger, cheaper and environment friendly.

Predictive Factors of Outcomes in Acute Subdural Hematoma Evacuation.

OBJECTIVE: This comparative cross-sectional study was conducted in the Departments of Trauma and Neurosurgery, Ayub Teaching Hospital, Abbottabad, Pakistan from September 2021 to February 2022 to study predictive factors of outcomes in acute subdural hematoma evacuation. METHODOLOGY: A total of 101 patients with confirmed diagnosis of acute subdural hematoma (ASDH) who underwent surgical evacuation by consultant neurosurgeon were included in the study. A detailed clinical proforma was designed to document all the clinical and demographic details of these patients at the time of admission. Glasgow Coma Scale outcome score (GOS) was used to assess the outcome of patients after the surgery. Sociodemographic and clinical parameters were associated with outcome of surgery in our study participants. RESULTS: Out of 101 patients, 55 (54.5%) were males and 46 (45.5%) were females. Mean age was 43.66±19.66 years with 7.39 as mean Glasgow Coma Scale (GCS) at presentation. Road traffic accident (RTA) 62 (61.4%) was most frequent mechanism of injury followed by fall from height (19.8%) and history of assault (13.9%). In our study, 59 patients had poor outcomes while 42 had good outcomes. Elder age, low GCS at presentation, and use of oral anticoagulant were associated with poor outcomes while pupillary reaction had no effect on the outcome after application of test of significance. CONCLUSION: More than half of the patients managed with surgical evacuation for acute subdural hematoma as per guidelines at our neurosurgical unit had poor outcomes according to Glasgow Coma Scale. In this study, advancing age (>60 years), low GCS score at presentation, and use of oral anticoagulation therapy emerged as significant risk factors for poor outcomes in participants. Pupillary reaction had no effect on outcomes as per this study but this needs further evaluation in future studies.