433 research outputs found
Position clamping of optically trapped microscopic non-spherical probes
We investigate the degree of control that can be exercised over an optically trapped microscopic non-spherical force probe. By position clamping translational and rotational modes in different ways, we are able to dramatically improve the position resolution of our probe with no reduction in sensitivity. We also demonstrate control over rotational-translational coupling, and exhibit a mechanism whereby the average centre of rotation of the probe can be displaced away from its centre
Factors associated with retention in a smoking cessation trial for persons with a mental illness: A descriptive study
Background
Exploring factors associated with retention in randomised trials provides insight into potential threats to internal and external study validity, and may inform the development of interventions to increase retention in future trials. Given a paucity of existing research in the field, a study was conducted to explore factors associated with retention in a smoking intervention trial involving persons with a mental illness, considering demographic and smoking characteristics, treatment condition and engagement in prior follow-up assessments.
Method
A descriptive study was undertaken using data derived from a RCT of a smoking cessation intervention initiated in four adult psychiatric inpatient units in New South Wales (NSW), Australia. Retention assessment was undertaken at 1, 6 and 12-months post-discharge. A Generalised Linear Mixed Model was adopted to explore associations between retention at any follow up time point and demographic and smoking characteristics. Chi square analyses explored the association between retention at all follow up time points and treatment condition, and binary logistic regression analyses assessed for relationships between retention at 12-month follow up and engagement in prior follow up assessments.
Results
Retention rates were 63, 56 and 60% at the 1, 6 and 12-month assessments, respectively. No association was found between retention at any follow-up time point and 13 of 15 demographic and smoking characteristics. Younger participants and those who identified to be Aboriginal and/or Torres Strait Islander were more likely to be retained (both psâ>â0.05). Retention rates did not vary according to treatment condition at any follow-up time point. Participants who completed a prior assessment were more likely to complete the 12âmonth assessment (both prior assessments: OR 10.7, pâ<â0.001; 6âmonth assessment: OR 6.01, pâ<â0.001; and 1âmonth assessment: OR 1.8, pâ=â0.002).
Conclusion
The underrepresentation of younger participants and those identifying to be Aboriginal and/or Torres Strait Islander may limit the generalisability of findings. Findings suggest that inclusion of multiple contacts during a trial follow up period may increase retention at the final assessment. Interventions to improve retention, overall and for those sub-groups less likely to be retained, in smoking trials involving persons with a mental illness are needed. Further assessment of sample characteristics, and also trial design factors, associated with retention in this field is warranted
Self-reported suboptimal sleep and receipt of sleep assessment and treatment among persons with and without a mental health condition in Australia: a cross sectional study
Background
Poor sleep and poor mental health go hand in hand and, together, can have an adverse impact on physical health. Given the already disproportionate physical health inequities experienced by people with a mental health condition worldwide, the need to consider and optimise sleep has been highlighted as a means of improving both physical and mental health status.
Sleep recommendations recently developed by the United Statesâ National Sleep Foundation incorporate a range of sleep parameters and enable the identification of âsuboptimalâ sleep. Among community-dwelling persons with and without a 12-month mental health condition in Australia, this study reports: [1] the prevalence of âsuboptimalâ sleep and [2] rates of sleep assessment by a health care clinician/service and receipt of and desire for sleep treatment.
Methods
A descriptive study (Nâ=â1265) was undertaken using self-report data derived from a cross-sectional telephone survey of Australian adults, undertaken in 2017.
Results
Fifteen per cent (nâ=â184) of participants identified as having a mental health condition in the past 12âmonths. Across most (7 of 8) sleep parameters, the prevalence of suboptimal sleep was higher among people with a mental health condition, compared to those without (all pâ<â0.05). The highest prevalence of suboptimal sleep for both groups was seen on measures of sleep duration (36â39% and 17â20% for people with and without a mental health condition, respectively). In terms of sleep assessment and treatment, people with a mental health condition were significantly more likely to: desire treatment (37% versus 16%), have been assessed (38% versus 12%) and have received treatment (30% versus 7%).
Conclusions
The prevalence of suboptimal sleep among persons with a mental health condition in Australia is significantly higher than those without such a condition, and rates of assessment and treatment are low for both groups, but higher for people with a mental health condition. Population health interventions, including those delivered as part of routine health care, addressing suboptimal sleep are needed
Uptake of smoking cessation aids by smokers with a mental illness
Psychiatric inpatient settings represent an opportunity to initiate the provision of tobacco cessation care to smokers with a mental illness. This study describes the use of evidence-based smoking cessation aids proactively and universally offered to a population of psychiatric inpatients upon discharge, and explores factors associated with their uptake. Data derived from the conduct of a randomised controlled trial were analysed in terms of the proportion of participants (N = 378) that utilised cessation aids including project delivered telephone smoking cessation counselling and nicotine replacement therapy (NRT), and Quitline support. Factors associated with uptake of cessation aids were explored using multivariable logistic regression analyses. A large proportion of smokers utilised project delivered cessation counselling calls (89 %) and NRT (79 %), while 11 % used the Quitline. The majority accepted more than seven project delivered telephone cessation counselling calls (52 %), and reported NRT use during more than half of their accepted calls (70 %). Older age, higher nicotine dependence, irregular smoking and seeing oneself as a non-smoker were associated with uptake of behavioural cessation aids. Higher nicotine dependence was similarly associated with use of pharmacological aids, as was NRT use whilst an inpatient. Most smokers with a mental illness took up a proactive offer of aids to support their stopping smoking. Consideration by service providers of factors associated with uptake may increase further the proportion of such smokers who use evidence-based cessation aids and consequently quit smoking successfully
Systematic review and meta-analysis of the provision of preventive care for modifiable chronic disease risk behaviours by mental health services
People with mental illness experience increased chronic disease burden, contributed to by a greater prevalence of modifiable chronic disease risk behaviours. Policies recommend mental health services provide preventive care for such risk behaviours. Provision of such care has not previously been synthesised. This review assessed the provision of preventive care for modifiable chronic disease risk behaviours by mental health services. Four databases were searched from 2006 to 2017. Eligible studies were observational quantitative study designs conducted in mental health services, where preventive care was provided to clients for tobacco smoking, harmful alcohol consumption, inadequate nutrition, or inadequate physical activity. Two reviewers independently screened studies, conducted data extraction and critical appraisal. Results were pooled as proportions of clients receiving or clinicians providing preventive care using random effects meta-analyses, by risk behaviour and preventive care element (ask/assess, advise, assist, arrange). Subgroup analyses were conducted by mental health service type (inpatient, outpatient, other/multiple). Narrative synthesis was used where meta-analysis was not possible. Thirty-eight studies were included with 26 amenable to meta-analyses. Analyses revealed that rates of assessment were highest for smoking (78%, 95% confidence interval [CI]:59%â96%) and lowest for nutrition (17%, 95% CI:1%â35%); with variable rates of care provision for all behaviours, care elements, and across service types, with substantial heterogeneity across analyses. Findings indicated suboptimal and variable provision of preventive care for modifiable chronic disease risk behaviours in mental health services, but should be considered with caution due to the very low quality of cumulative evidence
A determination of <A^2> and the non-perturbative vacuum energy of Yang-Mills theory in the Landau gauge
We discuss the 2-point-particle-irreducible (2PPI) expansion, which sums
bubble graphs to all orders, in the context of SU(N) Yang-Mills theory in the
Landau gauge. Using the method we investigate the possible existence of a gluon
condensate of mass dimension two, , and the corresponding non-zero vacuum
energy. This condensate gives rise to a dynamically generated mass for the
gluon.Comment: 12 pages, 3 eps figures; v2 : wrong use of "enhancement" instead of
"suppression" corrected; v3: version accepted for publication in Phys.Lett.
Macrophage Ontogeny Underlies Differences in Tumor-Specific Education in Brain Malignancies.
Extensive transcriptional and ontogenetic diversity exists among normal tissue-resident macrophages, with unique transcriptional profiles endowing the cells with tissue-specific functions. However, it is unknown whether the origins of different macrophage populations affect their roles in malignancy. Given potential artifacts associated with irradiation-based lineage tracing, it remains unclear if bone-marrow-derived macrophages (BMDMs) are present in tumors of the brain, a tissue with no homeostatic involvement of BMDMs. Here, we employed multiple models of murine brain malignancy and genetic lineage tracing to demonstrate that BMDMs are abundant in primary and metastatic brain tumors. Our data indicate that distinct transcriptional networks in brain-resident microglia and recruited BMDMs are associated with tumor-mediated education yet are also influenced by chromatin landscapes established before tumor initiation. Furthermore, we demonstrate that microglia specifically repress Itga4 (CD49D), enabling its utility as a discriminatory marker between microglia and BMDMs in primary and metastatic disease in mouse and human
Interrogation of the Microenvironmental Landscape in Brain Tumors Reveals Disease-Specific Alterations of Immune Cells
Brain malignancies encompass a range of primary and metastatic cancers, including low-grade and high-grade gliomas and brain metastases (BrMs) originating from diverse extracranial tumors. Our understanding of the brain tumor microenvironment (TME) remains limited, and it is unknown whether it is sculpted differentially by primary versus metastatic disease. We therefore comprehensively analyzed the brain TME landscape via flow cytometry, RNA sequencing, protein arrays, culture assays, and spatial tissue characterization. This revealed disease-specific enrichment of immune cells with pronounced differences in proportional abundance of tissue-resident microglia, infiltrating monocyte-derived macrophages, neutrophils, and T cells. These integrated analyses also uncovered multifaceted immune cell activation within brain malignancies entailing converging transcriptional trajectories while maintaining disease- and cell-type-specific programs. Given the interest in developing TME-targeted therapies for brain malignancies, this comprehensive resource of the immune landscape offers insights into possible strategies to overcome tumor-supporting TME properties and instead harness the TME to fight cancer
On the electromagnetic inverse scattering problem
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46179/1/205_2004_Article_BF00282681.pd
Symmetries and Elasticity of Nematic Gels
A nematic liquid-crystal gel is a macroscopically homogeneous elastic medium
with the rotational symmetry of a nematic liquid crystal. In this paper, we
develop a general approach to the study of these gels that incorporates all
underlying symmetries. After reviewing traditional elasticity and clarifying
the role of broken rotational symmetries in both the reference space of points
in the undistorted medium and the target space into which these points are
mapped, we explore the unusual properties of nematic gels from a number of
perspectives. We show how symmetries of nematic gels formed via spontaneous
symmetry breaking from an isotropic gel enforce soft elastic response
characterized by the vanishing of a shear modulus and the vanishing of stress
up to a critical value of strain along certain directions. We also study the
phase transition from isotropic to nematic gels. In addition to being fully
consistent with approaches to nematic gels based on rubber elasticity, our
description has the important advantages of being independent of a microscopic
model, of emphasizing and clarifying the role of broken symmetries in
determining elastic response, and of permitting easy incorporation of spatial
variations, thermal fluctuations, and gel heterogeneity, thereby allowing a
full statistical-mechanical treatment of these novel materials.Comment: 21 pages, 4 eps figure
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