Influence of alkaline activators on mechanical properties of environmentally friendly geopolymer concrete under different curing regimes.

Previous studies highlighted the significance of tailoring alkaline activators (AA) to specific fly ash (FA) sources for optimal properties of geopolymer concrete (GPC). This study examines the influence of various AA's properties on mechanical properties and microstructures of local low-calcium FA-based GPC under varying curing conditions. A comprehensive investigation consists of several factors such as NaOH molarities (10 M, 12 M, 14 M, 16 M), Na 2 SiO 3 / N a O H ratios (1.5, 2.0, 2.5) and A A / F A ratios (0.5, 0.6). The results reveal a complex relationship, demonstrating that NaOH molarity positively influences compressive strength up to a threshold of 14 M, beyond which an adverse effect was observed while, the flexural strength was increased up to 16 M. Moreover, the study highlights the complex relationship between Na 2 SiO 3 / N a O H ratios and mechanical strengths. Notably, these properties exhibited an increase as the ratio rose up to 2.0, but a subsequent decrease was observed when the ratio reached 2.5. Moreover, proposed regression equations predict the compressive and flexural strengths of both ambient-cured GPC and heat-cured GPC with marginal statistical errors. The optimal GPC mix exhibited 49% lower embodied CO 2 emissions than the corresponding OPC concrete. GPC has higher cost, but it exhibited lower cost-to-strength ratio compared to OPC concrete.

The Impact of Contemporary Antiretroviral Drugs on Atherosclerosis and Its Complications in People Living With HIV: A Systematic Review.

With the advent of modern antiretroviral therapy (ART), human immunodeficiency virus (HIV) infection has been modified into a chronic manageable condition, prolonging the lifespan of people living with HIV (PLHIV). This has resulted in an increased non-AIDS-related morbidity in the HIV-infected population. Our aim is to study the role of contemporary ART in tackling the risk of atherosclerosis and cardiovascular disease (CVD) in PLHIV. We searched through the databases of PubMed, PubMed Central, and Cochrane Library for pertinent articles using the medical subject headings (MeSH) "HIV infection", "Atherosclerosis", and "Antiretroviral agents". The articles published in the past five years were retrieved, screened for relevance, and assessed for quality before being included in the review. This review was performed following the PRISMA 2020 guidelines. The results indicate that the incidence of dyslipidemia with integrase strand transfer inhibitors (INSTIs) is greater than with non-nucleoside reverse transcriptase inhibitors (NNRTIs) and lesser than with protease inhibitors (PIs). INSTIs are indispensably associated with weight gain and obesity. High triglyceride (TG) and oxidized low-density lipoproteins to low-density lipoproteins (oxLDL/LDL) ratio levels and low high-density lipoprotein (HDL) levels are seen in patients taking PIs. A higher incidence of hypertension and metabolic syndrome (MetS) was noticed with INSTIs compared to NNRTIs. PI intake for >5 years increases the risk of subclinical atherosclerosis. Increased risk of myocardial infarction with INSTIs was observed in a study, while another study reported decreased risk. HIV infection independently increases the risk for atherosclerosis and CVD. Although contemporary ART decreases this enhanced risk, it inherently increases the risk for abnormal lipid profile, MetS, weight gain, and obesity. Further research into the risk of atherosclerosis and CVD with newer ART drugs is essential for decoding the underlying mechanisms and preventing adverse cardiac outcomes in PLHIV.

Which Is Better? Rate Versus Rhythm Control in Atrial Fibrillation: A Systematic Review.

Atrial fibrillation (AF) is a common arrhythmia associated with significant morbidity and mortality. The optimal approach to managing AF, specifically rate control versus rhythm control, remains a topic of debate in clinical practice. This systematic review aims to compare the rate control and rhythm control strategies based on their clinical outcomes, quality of life, and adverse events associated with them. A comprehensive search was conducted using PubMed, Google Scholar, Science Direct, Research Gate, MEDLINE (Medical Literature Analysis and Retrieval System Online), Scopus, and Embase (Excerpta Medica dataBASE) databases. A total of 1657 research papers were identified through the search strategy, and after applying the eligibility criteria, 28 studies were selected for the analysis. The studies encompassed a range of methodologies, including randomized controlled trials, observational studies, and meta-analyses. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for study selection, data extraction, and analysis. The outcomes of interest included all: cause mortality, stroke, bleeding events, cardiovascular hospitalizations, quality of life, and adverse effects of treatment. Data were synthesized and presented in tables, charts, and forest plots for meta-analysis where appropriate. The results indicate that both rate control and rhythm control strategies have their own merits and limitations, with the outcomes varying based on patient characteristics and comorbidities. While rhythm control strategies may lead to better symptom control and improved quality of life, rate control strategies may be associated with lower risks of adverse events and complications. This systematic review provides a comprehensive overview of the current evidence regarding rate and rhythm control strategies in AF management, offering insights for clinical decision-making and highlighting the need for individualized treatment approaches.