Study of heterogeneous nucleation of eutectic Si in high-purity Al-Si alloys with Sr addition

The official published version can be accessed from the link below - Copyright @ 2010 The Minerals, Metals & Materials Society and ASM InternationalAl-5 wt pct Si master-alloys with controlled Sr and/or P addition/s were produced using super purity Al 99.99 wt pct and Si 99.999 wt pct materials in an arc melter. The master-alloy was melt-spun resulting in the production of thin ribbons. The Al matrix of the ribbons contained entrained Al-Si eutectic droplets that were subsequently investigated. Differential scanning calorimetry, thermodynamic calculations, and transmission electron microscopy techniques were employed to examine the effect of the Sr and P additions on eutectic undercoolings and nucleation phenomenon. Results indicate that, unlike P, Sr does not promote nucleation. Increasing Sr additions depressed the eutectic nucleation temperature. This may be a result of the formation of a Sr phase that could consume or detrimentally affect potent AlP nucleation sites.This work is financially supported by the Higher Education Commission of Pakistan and managerially supported from the OAD

Cognitive impairment, fatigue and depression in multiple sclerosis: Is there a difference between benign and non-benign MS?

Available online 21 March 2023Introduction: Multiple Sclerosis (MS) is a chronic inflammatory and degenerative disease of the central nervous system (CNS). The severity of disability in people with MS (PwMS) is generally measured with the Expanded Disability Status Scale (EDSS). A variant of MS known as ‘benign MS’ (BMS) has been defined as an EDSS score of 3 or lower, combined with a disease duration of 10 years or longer; however, there is disagreement in the field about whether BMS really exists. Given that the EDSS does not capture cognitive issues, communication dysfunction, fatigue, depression, or anxiety properly, its ability to accurately represent disability in all PwMS, including BMS, remains questionable. Methods: In this study, 141 persons with BMS (PwBMS) were included, consisting of 115 females (82%) and 26 males (18%) with a mean age of 50.8 (±8.68). A computerized test battery (NeuroTrax®) was used to assess cognition, covering seven cognitive domains (memory, executive function, visual-spatial processing, verbal function, attention, information processing, and motor skills). Fatigue was measured using the Fatigue Severity Scale (FSS). The Beck Depression Inventory (BDI) was used to assess symptoms of depression. Cognitive impairment was defined for this study as when someone has a score lower than 85 in at least two subdomains of the cognitive test battery. Rates of impairment were compared to 158 persons with non-benign MS (PwNBMS; with a disease duration of 10 years and longer and an EDSS score higher than 3) and 487 PwMS with a disease duration of fewer than 10 years. Results: Cognitive impairment was found in 38% of PwBMS and in 66% of PwNBMS (p<0.001). In PwBMS, the lowest rate of impairment was found in the verbal function domain (18%) and the highest rate of impairment in the domain of information processing (32%). Fatigue and depression were found in 78% and 55% of all PwBMS, with no difference in these rates between PwBMS and PwNBMS (p = 0.787 and p = 0.316 resp.) Conclusion: Cognitive impairment, fatigue and depression are common among people with an EDSS-based definition of benign MS. These aspects should be incorporated into a new and better definition of truly benign MSHans Bogaardt, Daniel Golan, Marissa A Barrera, Stacie Attrill, Olivia Kaczmarek, Myassar Zarif, Barbara Bumstead, Marijean Buhse, Jeffrey Wilken, Glen M Doniger, Laura M Hancock, Iris-Katharina Penner, June Halper, Sarah A Morrow, Thomas J Covey, Mark Gudesblat

Risk of Serious Infections in Patients with Psoriasis on Biologic Therapies: A Systematic Review and Meta-Analysis

A comprehensive evaluation of the risk of serious infections in biologic therapies for psoriasis is lacking. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) and prospective cohort studies reporting serious infections in people taking any licensed biologic therapy for psoriasis compared with those taking placebo, nonbiologic therapy, or other biologic therapies. The quality of the studies was assessed using Grading of Recommendations Assessment, Development and Evaluation criteria. No significant heterogeneity was detected in data from 32 RCTs (n = 13,359 participants) and one cohort study (n = 4,993 participants). In adults, low- to very-low-quality RCT data showed no significant difference between any biologic therapy and placebo at weeks 12–16 (overall pooled Peto odds ratio = 0.71, 95% confidence interval = 0.36–1.41) and weeks 20–30 (odds ratio = 2.27, 95% confidence interval = 0.45–11.49). No significant differences were found in any of the other comparisons in underpowered RCT data. Prospective cohort study data of low quality suggests that only adalimumab (adjusted hazard ratio [adjHR] = 2.52, 95% confidence interval = 1.47–4.32) was associated with a significantly higher risk of serious infection compared with retinoid and/or phototherapy in adults. No association between biologic therapies and serious infections in patients with psoriasis who were eligible for RCTs was detected. Further observational studies are needed to inform the uncertainty around this risk in the real world

Sub-second periodicity in a fast radio burst

Fast radio bursts (FRBs) are millisecond-duration flashes of radio waves that are visible at distances of billions of light-years. The nature of their progenitors and their emission mechanism remain open astrophysical questions. Here we report the detection of the multi-component FRB 20191221A and the identification of a periodic separation of 216.8(1) ms between its components with a significance of 6.5 sigmas. The long (~3 s) duration and nine or more components forming the pulse profile make this source an outlier in the FRB population. Such short periodicity provides strong evidence for a neutron-star origin of the event. Moreover, our detection favours emission arising from the neutron-star magnetosphere, as opposed to emission regions located further away from the star, as predicted by some models.Comment: Updated to conform to the accepted versio

CHIME/FRB Discovery of 25 Repeating Fast Radio Burst Sources

We present the discovery of 25 new repeating fast radio burst (FRB) sources found among CHIME/FRB events detected between 2019 September 30 and 2021 May 1. The sources were found using a new clustering algorithm that looks for multiple events co-located on the sky having similar dispersion measures (DMs). The new repeaters have DMs ranging from $\sim$220 pc cm$^{-3}$ to $\sim$1700 pc cm$^{-3}$, and include sources having exhibited as few as two bursts to as many as twelve. We report a statistically significant difference in both the DM and extragalactic DM (eDM) distributions between repeating and apparently nonrepeating sources, with repeaters having lower mean DM and eDM, and we discuss the implications. We find no clear bimodality between the repetition rates of repeaters and upper limits on repetition from apparently nonrepeating sources after correcting for sensitivity and exposure effects, although some active repeating sources stand out as anomalous. We measure the repeater fraction and find that it tends to an equilibrium of $2.6_{-2.6}^{+2.9}$% over our exposure thus far. We also report on 14 more sources which are promising repeating FRB candidates and which merit follow-up observations for confirmation.Comment: Submitted to ApJ. Comments are welcome and follow-up observations are encouraged

The multiple faces of self-assembled lipidic systems

Lipids, the building blocks of cells, common to every living organisms, have the propensity to self-assemble into well-defined structures over short and long-range spatial scales. The driving forces have their roots mainly in the hydrophobic effect and electrostatic interactions. Membranes in lamellar phase are ubiquitous in cellular compartments and can phase-separate upon mixing lipids in different liquid-crystalline states. Hexagonal phases and especially cubic phases can be synthesized and observed in vivo as well. Membrane often closes up into a vesicle whose shape is determined by the interplay of curvature, area difference elasticity and line tension energies, and can adopt the form of a sphere, a tube, a prolate, a starfish and many more. Complexes made of lipids and polyelectrolytes or inorganic materials exhibit a rich diversity of structural morphologies due to additional interactions which become increasingly hard to track without the aid of suitable computer models. From the plasma membrane of archaebacteria to gene delivery, self-assembled lipidic systems have left their mark in cell biology and nanobiotechnology; however, the underlying physics is yet to be fully unraveled

The prevalence of obesity and the knowledge, attitude and practice of healthy lifestyle among the adult population in Kampung Banyuk, Kampung Kerto and Kampung Langup

Background Obesity has become a great public health concern and prevent!ive measures need to be done. Objective The objective of this research is to determine the prevalence ofobesity and their knowledge, attitude and practices (KAP) towards a healthy lifestyle among the residents in Kampung Banyok, Kampung Kerto and Kampung Langup. Methods A cross-sectional study was done among 126 randomly selected villagers aged 18 years and above from the three selected villages. They were interviewed based on a questionnaire and their body mass index (BMI) was calculated. Results It was found that more than half of the respondents are obese. Among the respondents, for the healthy lifestyle component, the level of good KAP is 69.2%, 46.8% and 60.3% respectively. As for obesity component, the level of good KAP is 60.3%, 54% and 54.8% respectively. Among the obese respondents, the level of knowledge and attitude on healthy lifestyle and obesity is better. Obese respondents have better obesity preventive practice while the non-obese respondents have better practice on healthy lifestyle. The only significant correlation noted was between knowledge and practice on obesity albeit a negative one. Conclusion The level of knowledge and attitude and practice on healthy lifestyle among the obese respondents are encouraged but more effort in the preventive practice ofobesity shou1d be done to reduce the prevalence.

Ocrelizumab versus Interferon Beta-1a in Relapsing Multiple Sclerosis

Supported by F. Hoffmann–La Roche

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries