Effect of Zinc and Severe Plastic Deformation on Mechanical Properties of AZ61 Magnesium Alloy.

This study investigates the effects of zinc (4 wt.%) and severe plastic deformation on the mechanical properties of AZ61 magnesium alloy through the stir-casting process. Severe plastic deformation (Equal Channel Angular Pressing (ECAP)) has been performed followed by T4 heat treatment. The microstructural examinations revealed that the addition of 4 wt.% Zn enhances the uniform distribution of ß-phase, contributing to a more uniformly corroded surface in corrosive environments. Additionally, dynamic recrystallization (DRX) significantly reduces the grain size of as-cast alloys after undergoing ECAP. The attained mechanical properties demonstrate that after a single ECAP pass, AZ61 + 4 wt.% Zn alloy exhibits the highest yield strength (YS), ultimate compression strength (UCS), and hardness. This research highlights the promising potential of AZ61 + 4 wt.% Zn alloy for enhanced mechanical and corrosion-resistant properties, offering valuable insights for applications in diverse engineering fields.

Mechanical and Corrosion Tests for Magnesium-Zinc/Ti-6Al-4V Composites by Gravity Casting.

A new Mg-4Zn X Ti-6Al-4V (TC4, of 0, 1, and 3 wt.%) alloy was successfully fabricated by a simple and low-cost gravity casting method and heat treatment at 150 °C for 24 h. The composite was examined by XRD, uniaxial tests, FESEM/EDS, potentiostat/EIS, and immersion tests for the material's microstructures, mechanical properties, electrochemical characteristics, and corrosion resistance. Experimental results indicate that heat treatment enables the precipitation of Zn along the Mg grain boundaries and drives the co-precipitation of Al around the TC4 particles and nearby grain boundaries. Uniaxial tensile tests reveal that TC4 reinforces the Mg-Zn matrix material with higher elastic modulus, ultimate tensile stress, and toughness. The heat treatment further enhanced these mechanical properties. Electrochemical tests show that 1 wt.% TC4 composite exhibits the highest open circuit potential among all tested samples, which implies the 1 wt.% TC4-added Mg-Zn is better resistant to the oxidation of the essential metals Mg, Zn, and Al. The immersion tests in the HBSS solution further show that the 1 wt.% TC4 composite has the lowest rise of pH values after 14 days, and EDS for the corroded surface signifies that Mg is the main element vulnerable to oxidation by corrosion.

A study of socio clinical, biochemical and electrocardiographic changes of yellow oleander seed poisoning in India.

Yellow oleander (Thevetia peruviana), which belongs to the Apocyanaceae family, is a common shrub seen throughout the tropics. All parts of the plant contain high concentrations of cardiac glycosides, which are toxic to cardiac muscle and the autonomic nervous system. The main objective of this study was to socio-clinical, biochemical and electrocardiographic changes of yellow oleander seed poisoning. This prospective observational study was conducted over a period of 6 months (March 2022 to September 2022). Oleander seed poison in most prevalent in the 21-40 years age. More the crushed seeds consumed and the delay to admission to the hospital for treatment poorer was the outcome. The most common GI symptoms of yellow oleander poisoning were vomiting (58 %), abdominal pain (28%), diarrhoea (9%), and palpitations (20%), dizziness (18%).Serum potassium levels that were measured during the admission were directly related to the ECG changes. ECG changes were more observed with patients those who consumed seeds in crushed form and this difference is statistically significant (P = 0.0001). Higher incidence of cardiotoxicity was noted with patients those who consumed poison on empty stomach compare to who consumed after food. The Electrocardiographic manifestations was found even with consumption of one seed, number of seeds consumptions independent of cardiotoxicity.Additonally higher mean Potassium value observed in patients who had cardiotoxicity when compared to patient who had no cardiotoxicity. Death of the patients in yellow oleander seed poisoning was independent of quantity of the seeds they have ingested.

Role of neutrophil-lymphocyte ratio as a prognostic marker for type 2 diabetic nephropathy among Indians.

Diabetic nephropathy/diabetic kidney disease (DKD) is one of the leading causes of renal failure. Early identification of the development or progression of diabetic nephropathy using appropriate screening and diagnostic tools is very important in order to provide timely and proper management. Inflammation plays a crucial role in development and progression of diabetic nephropathy. The aim of this study was to evaluate the relationship of inflammatory markers (neutrophil-to-lymphocyte ratio-NLR) as an early indicator to prevent the progression of diabetic kidney disease. A total of 158 patients with type 2 diabetes mellitus were distributed into three groups according urinary albumin-to-creatinine ratio. Levels of inflammatory markers neutrophil-to-lymphocyte ratio was recorded and compared among the three groups. Significant differences were detected between the groups in terms of neutrophil-to-lymphocyte ratio (p = 0.000).Characteristic curve analysis of inflammatory markers and microalbuminuria prediction demonstrated an area under curve (AUC) of 0.869 for neutrophil-to-lymphocyte ratio (p = 0.000). A NLR cut-off point of 2.2 has 72.3 % sensitivity and 78.1 % specificity, which suggested sufficient accuracy. Increased neutrophil-to-lymphocyte ratio was significantly correlated with diabetic nephropathy progression and increased neutrophil-to-lymphocyte ratio can be considered as an early indicator and a prognostic risk marker of diabetic nephropathy.

Effect of SiC Nanoparticles on AZ31 Magnesium Alloy.

Magnesium alloys are attractive for the production of lightweight parts in modern automobile and aerospace industries due to their advanced properties. Their mechanical properties are usually enhanced by the incorporation with reinforcement particles. In the current study, reinforced AZ31 magnesium alloy was fabricated through the addition of bulk Al and the incorporation of SiC nanoparticles using a stir casting process to obtain AZ31-SiC nanocomposites. Scanning electron microscope (SEM) investigations revealed the formation of Mg17Al12 lamellar intermetallic structures and SiC clusters in the nanocomposites. Energy dispersive spectroscopy (EDS) detected the uniform distribution of SiC nanoparticles in the AZ31-SiC nanocomposites. Enhancements in hardness and yield strength (YS) were detected in the fabricated nanocomposites. This behavior was referred to a joint strengthening mechanisms which showed matrix-reinforcement coefficient of thermal expansion (CTE) and elastic modulus mismatches, Orowan strengthening, and load transfer mechanism. The mechanical properties and wear resistance were gradually increased with an increase in SiC content in the nanocomposite. The maximum values were obtained from nanocomposites containing 1 wt% of SiC (AZ31-1SiC). AZ31-1SiC nanocomposite YS and hardness were improved by 27% and 30%, respectively, compared to AZ31 alloy. This nanocomposite also exhibited the highest wear resistance; its wear mass loss and depth of the worn surface decreased by 26% and 15%, respectively, compared to AZ31 alloy.

Analysis of mutations within the 5' untranslated region, interferon sensitivity region, and PePHD region as a function of response to interferon therapy in hepatitis C virus-infected patients in India.

Mutations in several subgenomic regions have been implicated in influencing response to interferon therapy; however, a comprehensive picture of Indian patients was lacking. Based on the viral load and clinical factors, 10 out of 15 patients were found to be complete responders, whereas 5 patients were nonresponders. The pretreatment viral RNA load of the patients was found to be between 5.20 and 6.13 log10 IU/ml, which eventually fell to 2.77 log10 IU/ml after 24 weeks of treatment, whereas in the case of nonresponders, the average was 5.38 log10 IU/ml. In order to study the influence of the hepatitis C virus genotype on the response to interferon therapy, the 5' untranslated region sequences of the samples were analyzed, which showed that genotype 3 patients responded better than genotype 1 patients. Additionally, the mutations in the interferon sensitivity-determining region (ISDR) of the NS5A protein and the double-stranded RNA-activated protein kinase-eukaryotic initiation factor 2 alpha phosphorylation homology domain (PePHD) of the E2 envelope protein, before and after treatment, were compared with nonresponder prototype J. Although, no clear correlation was found in the case of the mutated ISDR, some significant changes in residues were observed in the PePHD region, which could be helpful in understanding the molecular basis of resistance to therapy. Interestingly, analysis of the quasispecies variations showed a change in genotype in one sample during treatment, which might have contributed to the resistance. The results suggest that the mutations in different regions of the viral genome might have a concerted effect on the response to interferon therapy.