Mechanical Properties,Crack Width,and Propagation of Waste Ceramic Concrete Subjected to Elevated Temperatures: A Comprehensive Study

Waste ceramic concrete (WOC) made from waste ceramic floor tiles has several economic and environmental benefits. Fire is one of the most common disasters in buildings, and WOC is a brittle construction material; therefore, the mechanical properties of WOC structures under high temperatures should be considered. According to previous studies, hybrid fiber can further reduce damage to concrete under high temperatures. Meanwhile, crack width and propagation are among the key characteristics of concrete materials that need to be considered, but few studies have focused on their behavior when subjected to elevated temperatures. The new concrete materials proposed by the authors are WOC and WOC-Hybrid. WOC was prepared with Natural Coarse Aggregates (NCA), Natural Fine Aggregate (NFA), Ordinary Portland Cement (OPC 43 grade), and ceramic waste tiles with 20% replacements for coarse aggregates, 10% replacements for fine aggregates, and 10% replacement for cement. In contrast, WOC-Hybrid was prepared with the addition of hybrid fiber (1% crimped steel fiber and 1% polyvinyl alcohol fiber) in WOC. The specimens were exposed to temperatures of 100–300 °C, and then the specimens were tested for tensile and compressive strength. The present study aims to find a new method to improve concrete resistance to elevated temperatures at the lowest costs by experimental and computational analysis via machine learning models. The application of machine learning models such as artificial neural networks (ANN) and multiple linear regression (MLR) was employed in this study to predict the compressive and tensile strength of concrete. The linear coefficient correlation (R²) and mean square error (MSE) were evaluated to investigate the performance of the models. Based on the experimental analysis, the results show that the effect of hybrid fiber on the crack width and propagation is greater than that on the crack width and propagation of WOC and PC after exposure to high temperatures. However, the enhanced effect of hybrid fiber on the mechanical properties, rack width, and propagation decreases after subjecting it to a high-temperature treatment, owing to the melting and ignition of hybrid fibers at high temperatures. Regarding the computational analysis, it was found that the developed MLR model shows higher efficiency than ANN in predicting the compressive and tensile strength of PC, WOC, and WOC-Hybrid concrete.     

Determination of intimin and Shiga toxin genes in Escherichia coli isolates from gastrointestinal contents of healthy broiler chickens in Kerman City, Iran

Shiga toxin-producing Escherichia coli (STEC) strains have emerged as food poisoning pathogens which can cause severe diseases in humans. Poultry can be readily and persistently colonized, leading to the excretion of the STEC strains in the gastrointestinal contents and becoming a potential risk for human infection. Two hundred and ninety E. coli isolates were recovered from the cecum and jejunum contents of 145 broiler chickens during the slaughter. The isolates were examined to determine the phylotypes and prevalence of stx1, stx2, and eae genes. E. coli isolates were segregated in four main phylogenetic group A (60.69 %), B1 (8.62 %), B2 (9.31 %), and D (21.38 %). The isolates from the cecal contents belonged to A (68.27 %), B1 (1.38 %), B2 (13.10 %), and D (17.24 %) phylogenetic groups. The E. coli isolates from the contents of the jejunum indicated that the isolates were distributed in four phylogenetic groups including 53.11 % (77 isolates) in A, 15.86 % (23 isolates) in B1, 5.52 % (8 isolates) in B2, and 25.51 % (37 isolates) in D group. Nine isolates (3.10 %) were positive for eae and stx2 genes. None of the isolates contained the stx1 gene. The positive isolates were distributed in three phylo-groups and four phylogenetic subgroups A (A₀, A₁), B1, and D (D₁, D₂). The four eae- and stx2-positive isolates from the cecal contents belonged to A₀, A₁, and D₁ phylo-subgroups; whereas five eae- and stx2-positive isolates from the jejunum contents fell into A₀, A₁, and D₁ phylo-subgroups and B1 phylo-group.     

Insight into prognostics,diagnostics, and management strategies for SARS CoV-2

The foremost challenge in countering infectious diseases is the shortage of effective therapeutics. The emergence of coronavirus disease (COVID-19) outbreak has posed a great menace to the public health system globally, prompting unprecedented endeavors to contain the virus. Many countries have organized research programs for therapeutics and management development. However, the longstanding process has forced authorities to implement widespread infrastructures for detailed prognostic and diagnostics study of severe acute respiratory syndrome (SARS CoV-2). This review discussed nearly all the globally developed diagnostic methodologies reported for SARS CoV-2 detection. We have highlighted in detail the approaches for evaluating COVID-19 biomarkers along with the most employed nucleic acid- and protein-based detection methodologies and the causes of their severe downfall and rejection. As the variable variants of SARS CoV-2 came into the picture, we captured the breadth of newly integrated digital sensing prototypes comprised of plasmonic and field-effect transistor-based sensors along with commercially available food and drug administration (FDA) approved detection kits. However, more efforts are required to exploit the available resources to manufacture cheap and robust diagnostic methodologies. Likewise, the visualization and characterization tools along with the current challenges associated with waste-water surveillance, food security, contact tracing, and their role during this intense period of the pandemic have also been discussed. We expect that the integrated data will be supportive and aid in the evaluation of sensing technologies not only in current but also future pandemics.

The foremost challenge in countering infectious diseases is the shortage of effective therapeutics.     

Temporary loss of perivascular aquaporin-4 in neocortex after transient middle cerebral artery occlusion in mice

The aquaporin-4 (AQP4) pool in the perivascular astrocyte membranes has been shown to be critically involved in the formation and dissolution of brain edema. Cerebral edema is a major cause of morbidity and mortality in stroke. It is therefore essential to know whether the perivascular pool of AQP4 is up- or down-regulated after an ischemic insult, because such changes would determine the time course of edema formation. Here we demonstrate by quantitative immunogold cytochemistry that the ischemic striatum and neocortex show distinct patterns of AQP4 expression in the reperfusion phase after 90 min of middle cerebral artery occlusion. The striatal core displays a loss of perivascular AQP4 at 24 hr of reperfusion with no sign of subsequent recovery. The most affected part of the cortex also exhibits loss of perivascular AQP4. This loss is of magnitude similar to that of the striatal core, but it shows a partial recovery toward 72 hr of reperfusion. By freeze fracture we show that the loss of perivascular AQP4 is associated with the disappearance of the square lattices of particles that normally are distinct features of the perivascular astrocyte membrane. The cortical border zone differs from the central part of the ischemic lesion by showing no loss of perivascular AQP4 at 24 hr of reperfusion but rather a slight increase. These data indicate that the size of the AQP4 pool that controls the exchange of fluid between brain and blood during edema formation and dissolution is subject to large and region-specific changes in the reperfusion phase.     

Home Use of Mini-Dose Glucagon As a Novel Treatment for Hypoglycemia Following Repeated,Prolonged Fasts in Type 1 Diabetes During Ramadan

OBJECTIVEWe determined the efficacy of self-administered subcutaneous mini-dose glucagon (MDG) to treat fasting-induced hypoglycemia in type 1 diabetes (T1D).RESEARCH DESIGN AND METHODSThis was a 4-week randomized, controlled crossover trial of 2-week MDG or 2-week oral glucose tablets (OG, control) involving 17 adults with T1D during Ramadan.RESULTSCompared with OG, MDG demonstrated a significant higher change in blood glucose from baseline to 30 min (Δ^t30, P < 0.001) and 1 h (Δ^t60, P = 0.02). The efficacy of MDG was preserved following ≥8 h fasting with significantly higher Δ^t30 in MDG (P = 0.01). Over the entire 2 weeks, MDG period had increased time in 70–180 mg/dL (P = 0.009) and less time <70 mg/dL (P = 0.04). MDG use resulted in higher completion of fasts compared with OG (P < 0.001).CONCLUSIONSMDG administration is an effective alternative to OG for prevention and treatment of fasting-induced hypoglycemia, offering improved glycemic control and promoting successful completion of prolonged fasts.     

Antibodies to mycobacteria in healthy and tuberculous badgers from two English counties

Sera obtained from 2 groups of badgers removed in bovine tuberculosis control operations have been examined for antibodies to 11 species of mycobacteria. From animals without post mortem evidence of tuberculosis, levels of antibodies to mycobacteria were found to increase with age, and different patterns of antibodies were found in animals coming from 2 different places. Some animals (5 out of 60) without evidence of progressive infection had antibodies suggesting contact with tubercle bacilli. Animals found to have tuberculosis at post mortem had increased levels of antibody to common mycobacterial antigen, as do humans with that disease. Only 2 of the 12 tuberculous animals had markedly more antibody binding to Tuberculin than to the other reagents. There was no evidence of greater specificity of antibody binding than was shown by sera of healthy badgers. The suggestion is made that contact with environmental mycobacteria might be a major factor determining distribution of tuberculosis amongst badgers.     

Prediction of Rockfill Materials’ Shear Strength Using Various Kernel Function-Based Regression Models—A Comparative Perspective

The mechanical behavior of the rockfill materials (RFMs) used in a dam’s shell must be evaluated for the safe and cost-effective design of embankment dams. However, the characterization of RFMs with specific reference to shear strength is challenging and costly, as the materials may contain particles larger than 500 mm in diameter. This study explores the potential of various kernel function-based Gaussian process regression (GPR) models to predict the shear strength of RFMs. A total of 165 datasets compiled from the literature were selected to train and test the proposed models. Comparing the developed models based on the GPR method shows that the superlative model was the Pearson universal kernel (PUK) model with an R-squared (R²) of 0.9806, a correlation coefficient (r) of 0.9903, a mean absolute error (MAE) of 0.0646 MPa, a root mean square error (RMSE) of 0.0965 MPa, a relative absolute error (RAE) of 13.0776%, and a root relative squared error (RRSE) of 14.6311% in the training phase, while it performed equally well in the testing phase, with R² = 0.9455, r = 0.9724, MAE = 0.1048 MPa, RMSE = 0.1443 MPa, RAE = 21.8554%, and RRSE = 23.6865%. The prediction results of the GPR-PUK model are found to be more accurate and are in good agreement with the actual shear strength of RFMs, thus verifying the feasibility and effectiveness of the model.     

The changing landscape for the management of patients with neovascular AMD: brolucizumab in clinical practice

Untreated neovascular age-related macular degeneration (nAMD) can lead to severe and permanent visual impairment. The chronic nature of the disease can have a significant impact on patients’ quality of life and an economic and time burden on medical retina (MR) services, with the care need outweighing the growth of resources that clinical services can access. The introduction of a new treatment into clinical services can be challenging, especially for services that are already under capacity constraints. Guidance for practical implementation is therefore helpful. Roundtable meetings, facilitated by Novartis UK, between a working group of MR experts with experience of leading and managing NHS retinal services in the intravitreal era were conducted between 2020 and 2021. These meetings explored various aspects and challenges of introducing a new anti-vascular endothelial growth factor (VEGF) therapy to the UK medical retina services. Provision of clear expert recommendations and practical guidance nationally, that can be adapted locally as required to support clinicians and healthcare professionals (HCPs), is valuable in supporting the introduction of a new anti-VEGF therapy within the NHS environment. The experts provide ophthalmologic HCPs with a collation of insights and recommendations to support the introduction and delivery of brolucizumab in their local service in the face of current and projected growth in demand for retina care.Subject terms: Macular degeneration, Education