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Production of ordinary Portland cement (OPC) is a carbon-intensive process that generates significant amounts of carbon dioxide (CO2) gas from the combustion of fossil fuels and thermal decomposition of limestone. Overall, cement industries are responsible for around 7 % of global CO2 emissions which poses a considerable threat to global climate change because of its greenhouse effects. The recent advent of geopolymer shows great potential to reduce carbon footprints by utilizing the industrial by-products, such as fly ash and ground granulated blast furnace slag (GGBS) and convert into a binding material. Generally, geopolymer binders are made using aluminosilicate compounds (fly ash and or GGBS) and an alkali activator (combination of sodium silicate and sodium hydroxide solution) called “two-part geopolymer”. Despite having superior engineering properties to conventional OPC concrete, geopolymer concrete has not been widely adopted in concrete industry so far. The safety hazards in mixing and handling geopolymer concrete posed by sodium hydroxide is one of the barriers to the adaptation of geopolymer concrete. Replacing liquid sodium hydroxide with less hazardous alkali materials, such as sodium carbonate powder not only makes the geopolymer binder less hazardous and easier for mixing and handling process but also makes it more environmentally sustainable because of its lower embodied energy compared to sodium hydroxide. This study investigates the environmental sustainability of structural grades one-part geopolymer concrete and compares the results with OPC concrete of same strength grades. This investigation also includes a comparison between various types of geopolymer concrete of 40 MPa and 50 MPa grades produced in previous studies. This study found that one-part geopolymer binder concrete emits around 65 % less CO2 than OPC concrete of same strength grades, which is also 23 % less than geopolymer concrete of same strength grades produced in previous studies.

The adsorption of Diphenolic acid (DPA), 2,4-Dichlorophenoxyacetic acid (2,4-D), and 2-methyl-4-chlorophenoxyacetic acid (MCPA) were examined in aqueous solution using activated carbon rice straw. The rice straw was activated by using two reagents, zinc chloride and phosphoric acid and named as RSZ, RSP, respectively. The results showed that both carbons have a relatively high adsorption capacity. Concerning the adsorption kinetic, the second-order model has better fit than the first model to experimental data. The adsorption yield of both carbons increased in the order: DPA < 2,4-D < MCPA. The pore volume diffusion model satisfactorily fitted the experiment on both carbons. Furthermore, solution pH has a high influence on the adsorption capacity for both carbons. The adsorption mechanism of selected pollutants onto carbon samples has been controlled by dispersion interaction π-π electrons and electrostatic interaction, moreover, the contribution of pore volume diffusion is the controlling mechanism of the overall rate of adsorption.

We report a 55-year-old man who underwent off-pump bypass surgery and had diffuse oozing and bruising postoperatively. His hematological profile had been normal preoperatively and he had been off antiplatelets for a week prior to surgery. Postoperatively, a detailed talk revealed that he had been on dietary supplements containing fish oil and garlic – both of which are known to affect platelet function. It behooves the surgeon and anesthetist to screen all patients preoperatively for the possibility of intake of any dietary supplements taken by the patient.

Background: Numerous immune cells are involved in developing multiple sclerosis (MS). Monocytes are believed to be the first to enter the brain and initiate inflammation. The role of monocyte subtypes in MS needs to be better understood. Objective: The current study aims to investigate the presence of different subsets of monocytes in relapsing-remitting MS (RRMS) Egyptian patients and their correlation with disease activity. Methods: This study included 44 RRMS patients (22 patients in relapse, 22 patients in remission), diagnosed according to the 2017 MacDonalds criteria, and 44 matched healthy controls. Personal and medical histories were taken from the patients, and the Expanded Disability Status Scale (EDSS) was used to evaluate the degree of impairment. Characterization of peripheral blood monocyte subsets was done by flow cytometry for all participants. Results: The percentage of classical, intermediate, and non-classical monocyte subsets showed a significant increase in RRMS patients than controls with p -values of 0.029, 0.049, and 0.043, respectively. In the RRMS patients, there were no statistically significant correlations ( p -values >0.05) between the EDSS scores, the duration of disease, and number of relapses in the past year and the percentages of the various monocyte subsets. Furthermore, there were no significant differences in the percentage of each monocyte subset between RRMS patients in remission and those experiencing a relapse ( p -values >0.05). However, patients with evidence of activity in magnetic resonance imaging (MRI) had a significantly high percentage of non-classical monocytes with a p -value of 0.002. Conclusion: In RRMS patients, the three monocyte subsets (classical, non-classical and intermediate) increase significantly regardless of the disease activity. This increase denotes the vital role of monocytes and innate immunity in MS pathology, especially the non-classical monocyte subset. These findings suggest that monocytes might be a promising MS therapeutic target., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.