2,630 research outputs found
Failure Modelling of Woven GFRP Bolted Joints under Quasi-Static Loading
Current work concentrates in modelling failure and damage of various woven fabric reinforcement system taken from selected literatures. Experimental observations under quasi-static loading revealed that initial failure occurs at notch vicinity consist of one or combinations of matrix cracking, splitting and laminate de-lamination. The crack then propagated along net-section of distance of about one notch radius size, which thereafter occurrence usually corresponds to catastrophic failures that seen significant tow fractures. The distance of cracked zone signifies ultimate material failure usually referred as “effective damage zone” that useful to be implemented within fracture mechanics concept. These complex morphologies mechanisms can be represented by implementing physically-based constitutive model. Series works of notched woven fabric composite systems plate were implemented within two-dimensional extended finite element method (XFEM) framework were carried out by implementing constitutive models based on basic material properties data of respective system. Good agreement is shown in comparison with experimental data in various and other closed-form approaches composite fabric systems
The XMM Cluster Survey: Active Galactic Nuclei and Starburst Galaxies in XMMXCS J2215.9-1738 at z=1.46
We use Chandra X-ray and Spitzer infrared observations to explore the AGN and
starburst populations of XMMXCS J2215.9-1738 at z=1.46, one of the most distant
spectroscopically confirmed galaxy clusters known. The high resolution X-ray
imaging reveals that the cluster emission is contaminated by point sources that
were not resolved in XMM observations of the system, and have the effect of
hardening the spectrum, leading to the previously reported temperature for this
system being overestimated. From a joint spectroscopic analysis of the Chandra
and XMM data, the cluster is found to have temperature T=4.1_-0.9^+0.6 keV and
luminosity L_X=(2.92_-0.35^+0.24)x10^44 erg/s extrapolated to a radius of 2
Mpc. As a result of this revised analysis, the cluster is found to lie on the
sigma_v-T relation, but the cluster remains less luminous than would be
expected from self-similar evolution of the local L_X-T relation. Two of the
newly discovered X-ray AGN are cluster members, while a third object, which is
also a prominent 24 micron source, is found to have properties consistent with
it being a high redshift, highly obscured object in the background. We find a
total of eight >5 sigma 24 micron sources associated with cluster members (four
spectroscopically confirmed, and four selected using photometric redshifts),
and one additional 24 micron source with two possible optical/near-IR
counterparts that may be associated with the cluster. Examining the IRAC colors
of these sources, we find one object is likely to be an AGN. Assuming that the
other 24 micron sources are powered by star formation, their infrared
luminosities imply star formation rates ~100 M_sun/yr. We find that three of
these sources are located at projected distances of <250 kpc from the cluster
center, suggesting that a large amount of star formation may be taking place in
the cluster core, in contrast to clusters at low redshift.Comment: Accepted for publication in ApJ, 16 pages, 10 figure
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Prevention of alcohol related harm though preconception care: A scoping review of barriers and enablers
Objective
To understand the perspectives of healthcare practitioners and women of reproductive age regarding addressing prevention of an alcohol exposed pregnancy before conception.
Methods
A scoping review of mixed methods, qualitative and quantitative research was conducted. Medline, CINAHL, EMBASE and PsychInfo databases were searched for literature published by March 2022. Data were extracted and synthesized.
Results
Twenty-three studies were included. Views varied between healthcare practitioners and women about addressing alcohol with women before pregnancy. Healthcare practitioners agreed prevention was important but believed they were ill-prepared to provide support, and that it might be intrusive if women were not contemplating pregnancy. Whereas women would welcome advice from healthcare practitioners, particularly if offered during appointments or visits for services related to reproductive health. A knowledge deficit about pregnancy and fetal harms from alcohol was expressed by both healthcare practitioners and women.
Conclusions
Investment in alcohol education and skills training for healthcare professionals is required to ensure a coherent message is communicated across services, and that shared decision making about healthcare between service users and health professionals is facilitated. Future research should explore implementation of interventions to prevent alcohol exposed pregnancy in settings where women are seeking reproductive health support
Study protocol: the ILANA study - exploring optimal implementation strategies for long-acting antiretroviral therapy to ensure equity in clinical care and policy for women, racially minoritised people and older people living with HIV in the UK - a qualitative multiphase longitudinal study design.
INTRODUCTION: Cabotegravir and rilpivirine (CAB+RPV long-acting (LA)) is recommended as a treatment for HIV-1 allowing people living with HIV to receive 2 monthly injectable treatment, rather than daily pills. Providing injectable therapy in a system designed to provide and manage study participants on oral treatments poses logistical challenges namely how resources are used to accommodate patient preference within constrained health economies with capacity limitations. In this pragmatic multicentre study, we aim to understand the implementation of CAB-RPV-LA administration in two settings via mixed methods to explore perspectives of participants and the clinical team delivering CAB+RPV LA. METHODS AND ANALYSIS: Women, racially minoritised people and older people are chronically under-represented in HIV clinical trials so the ILANA trial has set recruitment caps to ensure recruitment of 50% women, 50% ethnically diverse people and 30% over 50 years of age to include a more representative study population. Using a mixed-methods approach, the primary objective is to identify and evaluate the critical implementation strategies for CAB+RPV LA in both hospital and community settings. Secondary objectives include evaluating feasibility and acceptability of CAB+RPV LA administration at UK clinics and community settings from the perspective of HIV care providers, nurses and representatives at community sites, evaluating barriers to implementation, the utility of implementation strategies and adherence. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Health Research Authority Research Ethics Committee (REC reference: 22/PR/0318). The dissemination strategy has been formulated with the SHARE Collaborative Community Advisory Board to maximise the impact of this work on clinical care and policy. This strategy draws on and leverages existing resources within the participating organisations, such as their academic infrastructure, professional relationships and community networks. The strategy will leverage the Public Engagement Team and press office to support dissemination of findings. TRIAL REGISTRATION NUMBER: NCT05294159
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Neonatal enteral feeding tubes as loci for colonisation by members of the Enterobacteriaceae
Background The objective of this study was to determine whether neonatal nasogastric enteral feeding tubes are colonised by the opportunistic pathogen Cronobacter spp. (Enterobacter sakazakii) and other Enterobacteriaceae, and whether their presence was influenced by the feeding regime. Methods One hundred and twenty-nine tubes were collected from two neonatal intensive care units (NICU). A questionnaire on feeding regime was completed with each sample. Enterobacteriaceae present in the tubes were identified using conventional and molecular methods, and their antibiograms determined. Results The neonates were fed breast milk (16%), fortified breast milk (28%), ready to feed formula (20%), reconstituted powdered infant formula (PIF, 6%), or a mixture of these (21%). Eight percent of tubes were received from neonates who were 'nil by mouth'. Organisms were isolated from 76% of enteral feeding tubes as a biofilm (up to 107 cfu/tube from neonates fed fortified breast milk and reconstituted PIF) and in the residual lumen liquid (up to 107 Enterobacteriaceae cfu/ml, average volume 250 µl). The most common isolates were Enterobacter cancerogenus (41%), Serratia marcescens (36%), E. hormaechei (33%), Escherichia coli (29%), Klebsiella pneumoniae (25%), Raoultella terrigena (10%), and S. liquefaciens (12%). Other organisms isolated included C. sakazakii (2%),Yersinia enterocolitica (1%),Citrobacter freundii (1%), E. vulneris (1%), Pseudomonas fluorescens (1%), and P. luteola (1%). The enteral feeding tubes were in place between 48 h (13%). All the S. marcescens isolates from the enteral feeding tubes were resistant to amoxicillin and co-amoxiclav. Of additional importance was that a quarter of E. hormaechei isolates were resistant to the 3rd generation cephalosporins ceftazidime and cefotaxime. During the period of the study, K. pneumoniae and S. marcescens caused infections in the two NICUs. Conclusion This study shows that neonatal enteral feeding tubes, irrespective of feeding regime, act as loci for the bacterial attachment and multiplication of numerous opportunistic pathogens within the Enterobacteriaceae family. Subsequently, these organisms will enter the stomach as a bolus with each feed. Therefore, enteral feeding tubes are an important risk factor to consider with respect to neonatal infections
Discovery of the X-ray selected galaxy cluster XMMU J0338.8+0021 at z = 1.49 - Indications for a young system with a forming brightest galaxy
We report on the discovery of a galaxy cluster at z = 1.490 originally
selected as an extended X-ray source in the XMM-Newton Distant Cluster Project.
Further observations carried out with the VLT-FORS2 spectrograph allowed the
spectroscopic confirmation of seven secure cluster members, providing a median
system redshift of z = 1.490 +/- 0.009. The color magnitude diagram of XMMU
J0338.8+0021 reveals the presence of a well populated red sequence with z-H ~
3, albeit with an apparent significant scatter in color. Since we do not detect
indications for strong star formation activity in any of the objects, the color
spread could indicate different stellar ages of the member galaxies. In
addition, we found the brightest cluster galaxy in a very active dynamical
state, with an interacting, merging companion located at a physical projected
distance of d ~ 20kpc. From the X-ray luminosity we estimate a cluster mass of
M200 ~ 1.2 x 10^(14) Msun. The data seem to suggest a scenario in which XMMU
J0338.8+0021 is a young system, possibly caught in a moment of active ongoing
mass assembly.Comment: 6 pages, 4 figures, 2 Table
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