The evolution of cutting forces during slot milling of unidirectional carbon fiber reinforced polymer (UD-CFRP) composites

Cutting forces generated during traditional machining of fiber reinforced polymer composites play an important role in determining machined surface quality. The cutting force signals also provide a live indicator of the dynamic behavior of the chip formation process. Cutting forces in machining FRPs are dependent primarily on the instantaneous fiber cutting angle, chip thickness, cutting edge geometry and the current state of cutting edge wear. In this study, effects of the cutting edge rake angle and tool wear on cutting force evolution during slot milling of unidirectional carbon fiber reinforced polymer (UD-CFRP) composite was investigated. The cutting forces were measured in the feed and normal directions and then transformed to the tangential and radial directions of the tool path. A simplified cutting force model consisting of a shearing region and a pressing was used to determine the shearing and friction force components. This allowed determination of the friction coefficient on the clearance face of the tool. It was found that the friction coefficient varied significantly with rake angle and fiber cutting angle. The effect of rake angle on cutting forces is more discernable in the shearing region with positive rake angle tool providing the most efficient cutting. Furthermore, correlations were found between machining damage and the magnitude and orientation of the resultant shearing force

Oral Class I and III antiarrhythmic drugs for maintaining sinus rhythm after catheter ablation of atrial fibrillation

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the effects of oral Class I and III antiarrhythmic drugs for maintaining sinus rhythm in patients undergoing catheter ablation, compared to catheter ablation alone, for atrial fibrillation (AF)

Efficacy of renal denervation as an adjunct to pulmonary vein isolation for atrial fibrillation treatment: a systematic review and meta-analysis

Aims: Catheter ablation, consisting of pulmonary vein isolation (PVI), is the most effective treatment modality for the management of symptomatic patients with atrial fibrillation (AF). Unfortunately, this procedure has a considerable relapse rate, ranging from 15 to 50% depending on AF type and other patient factors. Hypertension (HTN) is associated with a higher risk of developing AF and can also be managed with a catheter-based procedure—renal denervation (RDN). This meta-analysis aimed to compare the effect of PVI with and without RDN in hypertensive patients with AF. Methods and results: OVID MEDLINE and Embase were searched on 1 February 2023 and trials that reported the effects of RDN on AF recurrence in hypertensive patients were included. A total of 637 patients across 8 randomised controlled trials were included. The results from the pooled analysis showed that when compared with PVI alone, RDN added to PVI: (1) Lowered AF recurrence [RR 0.67 (0.53, 0.85), P = 0.001, I2 = 23%, NNT = 5.9 patients]; (2) Reduced both systolic blood pressure and diastolic blood pressure, with medium effect size, as reflected by standardised mean differences of 0.5 (P = 0.02, I2 = 80%) and 0.43 (P = 0.006, I2 = 60%), respectively; and (3) was not associated with a decrease in estimated glomerular filtration rate (+7.19 mL/min/1.73 m2, P = 0.15, I2 = 89%). Conclusion: Adding RDN to PVI in patients with AF and resistant HTN was associated with a reduction of blood pressure levels and AF recurrence. Consideration to RDN should be given as an adjunctive treatment for patients with AF and resistant HTN

Capicua regulates neural stem cell proliferation and lineage specification through control of Ets factors

Capicua (Cic) is a transcriptional repressor mutated in the brain cancer oligodendroglioma. Despite its cancer link, little is known of Cic’s function in the brain. We show that nuclear Cic expression is strongest in astrocytes and neurons but weaker in stem cells and oligodendroglial lineage cells. Using a new conditional Cic knockout mouse, we demonstrate that forebrain-specific Cic deletion increases proliferation and self-renewal of neural stem cells. Furthermore, Cic loss biases neural stem cells toward glial lineage selection, expanding the pool of oligodendrocyte precursor cells (OPCs). These proliferation and lineage effects are dependent on de-repression of Ets transcription factors. In patient-derived oligodendroglioma cells, CIC re-expression or ETV5 blockade decreases lineage bias, proliferation, self-renewal, and tumorigenicity. Our results identify Cic as an important regulator of cell fate in neurodevelopment and oligodendroglioma, and suggest that its loss contributes to oligodendroglioma by promoting proliferation and an OPC-like identity via Ets overactivity

Compliance of smokeless tobacco supply chain actors and products with tobacco control laws in Bangladesh, India and Pakistan: protocol for a multicentre sequential mixed-methods study

Introduction: South Asia is home to more than 300 million smokeless tobacco (ST) users. Bangladesh, India and Pakistan as signatories to the Framework Convention for Tobacco Control (FCTC) have developed policies aimed at curbing the use of tobacco. The objective of this study is to assess the compliance of ST point-of-sale (POS) vendors and the supply chain with the articles of the FCTC and specifically with national tobacco control laws. We also aim to assess disparities in compliance with tobacco control laws between ST and smoked tobacco products. Methods and analysis: The study will be carried out at two sites each in Bangladesh, India and Pakistan. We will conduct a sequential mixed-methods study with five components: (1) mapping of ST POS, (2) analyses of ST samples packaging, (3) observation, (4) survey interviews of POS and (5) in-depth interviews with wholesale dealers/suppliers/manufacturers of ST. We aim to conduct at least 300 POS survey interviews and observations, and 6-10 in-depth interviews in each of the three countries. Data collection will be done by trained data collectors. The main statistical analysis will report the frequencies and proportions of shops that comply with the FCTC and local tobacco control policies, and provide a 95% CI of these estimates. The qualitative in-depth interview data will be analysed using the framework approach. The findings will be connected, each component informing the focus and/or design of the next component. Ethics and dissemination: Ethical approvals for the study have been received from the Health Sciences Research Governance Committee at the University of York, UK. In-country approvals were taken from the National Bioethics Committee in Pakistan, the Bangladesh Medical Research Council and the Indian Medical Research Council. Our results will be disseminated via scientific conferences, peer-reviewed research publications and press releases

Effects of oral creatine supplementation on body composition and objective physical function in rheumatoid arthritis patients. A randomised controlled trial

Objective: Muscle wasting (‘rheumatoid cachexia’) is evident in most rheumatoid arthritis (RA) patients, including those with well-controlled disease, and contributes substantially to the reductions in strength and physical function that are characteristic of this disease. The aim of this randomized controlled trial was to investigate the efficacy of oral creatine (Cr) supplementation on improving muscle mass, strength and function in stable RA patients. Method: Forty RA patients were randomized to 12 weeks supplementation of Cr or placebo, in a double-blind fashion. Body composition (by whole-body dual-energy X-ray absorptiometry, DXA, and bioelectrical impedance spectroscopy, BIS), strength and objectively-assessed physical function measures were taken at baseline, week 12, and week 24 (i.e. after 12 weeks of treatment withdrawal). Data was analyzed by ANCOVA. Results: Cr supplementation increased appendicular lean mass (ALM; a surrogate DXA measure of muscle mass) by (mean±SE) 0.52±0.13kg (P=0.004 vs placebo), and total LM by 0.60±0.37kg (P=0.158 vs placebo). The increment in LM by DXA corresponded with the elevation in intracellular water (ICW) estimated by BIS (0.64±0.22 L, P=0.035 vs placebo). However, the observed increases in ALM, total LM and ICW were not accompanied by improvements in isometric knee extensor strength (P=0.408), hand-grip strength (P=0.833), or objectively assessed function (30s sit-to-stand, 50’ walk, 8’ up-&-go, estimated VO2max; P’s=0.335-0.764) Conclusion: Twelve weeks of Cr supplementation improved muscle mass, but not strength or objectively-measured physical function in RA patients. As no adverse treatment-related effects occurred, Cr supplementation appears to be a safe and acceptable adjunct treatment for attenuating muscle loss in RA patients. This treatment may be especially suitable for patients with severe rheumatoid cachexia