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Background This study examines the 20-year trend of suicide in 46 Muslim-majority countries throughout the world and compares their suicide rates and trends with the global average. Ecological-level associations between the proportion of the Muslim population, the age-standardized suicide rates, male-to-female suicide rate ratio, and the Human Development Index (HDI) in 2019 were examined. Methods Age-standardized suicide rates were extracted from the WHO Global Health Estimates database for the period between 2000 and 2019. The rates in each country were compared with the age-standardized global average during the past 20 years. The countries were further grouped according to their regions/sub-regions to calculate the regional and sub-regional weighted age-standardized suicide rates involving Muslim-majority countries. Correlation analyses were conducted between the proportion of Muslims, age-standardized suicide rate, male: female suicide rate ratio, and the HDI in all countries. Joinpoint regression was used to analyze the age-standardized suicide rates in 2000-2019. Results The 46 countries retained for analysis included an estimated 1.39 billion Muslims from a total worldwide Muslim population of 1.57 billion. Of these countries, eleven (23.9%) had an age-standardized suicide rate above the global average in 2019. In terms of regional/sub-regional suicide rates, Muslim-majority countries in the Sub-Saharan region recorded the highest weighted average age-standardized suicide rate of 10.02/100,000 population, and Southeastern Asia recorded the lowest rate (2.58/100,000 population). There were significant correlations between the Muslim population proportion and male-to-female rate ratios (r=-0.324, p=0.028), HDI index and age-standardized suicide rates (r=-0.506, p<0.001), and HDI index and male-to-female rate ratios (r=0.503, p<0.001) in 2019. Joinpoint analysis revealed that seven Muslim-majority countries (15.2%) recorded an increase in the average annual per

Microgels are interesting as potential delivery systems for antimicrobial peptides. In order to elucidate membrane interactions of such systems, we here investigate effects of microgel charge density on antimicrobial peptide loading and release, as well as consequences of this for membrane interactions and antimicrobial effects, using ellipsometry, circular dichroism spectroscopy, nanoparticle tracking analysis, dynamic light scattering and z-potential measurements. Anionic poly(ethyl acrylate-co-methacrylic acid) microgels were found to incorporate considerable amounts of the cationic antimicrobial peptides LL-37 (LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES) and DPK-060 (GKHKNKGKKNGKHNGWKWWW) and to protect incorporated peptides from degradation by infection-related proteases at high microgel charge density. As a result of their net negative z-potential also at high peptide loading, neither empty nor peptide-loaded microgels adsorb at supported bacteria-mimicking membranes. Instead, membrane disruption is mediated almost exclusively by peptide release. Mirroring this, antimicrobial effects against several clinically relevant bacteria (methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa) were found to be promoted by factors facilitating peptide release, such as decreasing peptide length and decreasing microgel charge density. Microgels were further demonstrated to display low toxicity towards erythrocytes. Taken together, the results demonstrate some interesting opportunities for the use of microgels as delivery systems for antimicrobial peptides, but also highlight several key factors which need to be controlled for their successful use., QC 20180327

Membrane interactions are critical for the successful use of inorganic nanoparticles as antimicrobial agents and as carriers of, or co-actives with, antimicrobial peptides (AMPs). In order to contribute to an increased understanding of these, we here investigate effects of particle size (42-208 nm) on layered double hydroxide (LDH) interactions with both bacteria-mimicking and mammalian-mimicking lipid membranes. LDH binding to bacteria-mimicking membranes, extraction of anionic lipids, as well as resulting membrane destabilization, was found to increase with decreasing particle size, also translating into size-dependent synergistic effects with the antimicrobial peptide LL-37. Due to strong interactions with anionic lipopolysaccharide and peptidoglycan layers, direct membrane disruption of both Gram-negative and Gram-positive bacteria is suppressed. However, LDH nanoparticles cause size-dependent charge reversal and resulting flocculation of both liposomes and bacteria, which may provide a mechanism for bacterial confinement or clearance. Taken together, these findings demonstrate a set of previously unknown behaviors, including synergistic membrane destabilization and dual confinement/killing of bacteria through combined LDH/AMP exposure, of potential therapeutic interest.

Membrane interactions are critical for the successful use of inorganic nanoparticles as antimicrobial agents and as carriers of, or co-actives with, antimicrobial peptides (AMPs). In order to contribute to an increased understanding of these, we here investigate effects of particle size (42-208 nm) on layered double hydroxide (LDH) interactions with both bacteria-mimicking and mammalian-mimicking lipid membranes. LDH binding to bacteria-mimicking membranes, extraction of anionic lipids, as well as resulting membrane destabilization, was found to increase with decreasing particle size, also translating into size-dependent synergistic effects with the antimicrobial peptide LL-37. Due to strong interactions with anionic lipopolysaccharide and peptidoglycan layers, direct membrane disruption of both Gram-negative and Gram-positive bacteria is suppressed. However, LDH nanoparticles cause size-dependent charge reversal and resulting flocculation of both liposomes and bacteria, which may provide a mechanism for bacterial confinement or clearance. Taken together, these findings demonstrate a set of previously unknown behaviors, including synergistic membrane destabilization and dual confinement/killing of bacteria through combined LDH/AMP exposure, of potential therapeutic interest.

Clogging of pore spaces of pervious rockfill detention dam during passage of suspended sediment laden flow through it, is one of the important issues which has been studied by some of researchers. Further study is still needed to achieve generable results to the real field condition. In this research we investigated semi empirically the initiation of sediment particle motion inside the pervious rockfill dam by conducting laboratory experiments alongwith dimensional analysis. A series of larger scale laboratory tests than previous studies has been conducted to collect experimental data. A dimensional analysis has been performed including all of effective hydraulic and physical parameters especially inertia of flow and rockfill characteristics. Applying of inertia of flow and rockfill characteristics have been done to the previously proposed formula for laminar flow to improve and make it applicable for turbulent flow through pervious rockfill dams. The derived equation has been calibrated using a linear regression analysis with a correlation coefficient (R2) of 0.92. It has been validated with a mean square error (MSE) of 4.46E-05 and correlation coefficient of 0.94 utilizing its predicted critical hydraulic gradient versus laboratory measured critical hydraulic gradient. The validation showed a good agreement between predicted and measured critical hydraulic gradients. This equation also compared with the equations proposed by two other researchers and the results indicated a better agreement of predicted critical hydraulic gradients by the derived equation in this study to the measured values than by two other equations. The correlation coefficients and mean square errors of the present study's and two other formulas were respectively, 0.94 and 4.46E-5, 0.75 and 0.0003, 0.48and 0.0293.The proposed formula in this study should be a guide for hydraulic engineers to design pervious rockfill detention dam such a way that no clogging of pore spaces take place during sed