724 research outputs found
High resolution 3D confocal microscope imaging of volcanic ash particles
We present initial results from a novel high resolution confocal microscopy study of the 3D surface structure of volcanic ash particles from two recent explosive basaltic eruptions, Eyjafjallajökull (2010) and Grimsvötn (2011), in Iceland. The majority of particles imaged are less than 100 μm in size and include PM10s, known to be harmful to humans if inhaled. Previous studies have mainly used 2D microscopy to examine volcanic particles. The aim of this study was to test the potential of 3D laser scanning confocal microscopy as a reliable analysis tool for these materials and if so to what degree high resolution surface and volume data could be obtained that would further aid in their classification. First results obtained using an Olympus LEXT scanning confocal microscope with a × 50 and × 100 objective lens are highly encouraging. They reveal a range of discrete particle types characterised by sharp or concave edges consistent with explosive formation and sudden rupture of magma. Initial surface area/volume ratios are given that may prove useful in subsequent modelling of damage to aircraft engines and human tissue where inhalation has occurred
The Discovery of New Galaxy Members in the NGC 5044 and NGC 1052 Groups
We present the results of neutral hydrogen (HI) observations of the NGC 5044
and NGC 1052 groups, as part of a GEMS (Group Evolution Multiwavelength Study)
investigation into the formation and evolution of galaxies in nearby groups.
Two new group members have been discovered during a wide-field HI imaging
survey conducted using the ATNF Parkes telescope. These results, as well as
those from followup HI synthesis and optical imaging, are presented here.
J1320-1427, a new member of the NGC 5044 Group, has an HI mass of
M_HI=1.05e9Msun and M_HI/L_B=1.65 Msun/Lsun, with a radial velocity of
v=2750km/s. The optical galaxy is characterised by two regions of star
formation, surrounded by an extended, diffuse halo. J0249-0806, the new member
of the NGC 1052 Group, has M_HI=5.4e8Msun, M_HI/L_R=1.13 Msun/Lsun and
v=1450km/s. The optical image reveals a low surface brightness galaxy. We
interpret both of these galaxies as irregular type, with J0249-0806 possibly
undergoing first infall into the NGC 1052 group.Comment: Accepted for publication in MNRAS. 21 pages, 13 figures. Also
available with high-resolution figures at
http://www.astro.livjm.ac.uk/~npfm/Papers/mmb04.ps.g
ReseArch with Patient and Public invOlvement: a RealisT evaluation - the RAPPORT study
Background
Patient and public involvement (PPI) is a prerequisite for many funding bodies and NHS research ethics approval. PPI in research is defined as research carried out with or by the public rather than to, about or for them. While the benefits of PPI have been widely discussed, there is a lack of evidence on the impact and outcomes of PPI in research.
Objectives
To determine the types of PPI in funded research, describe key processes, analyse the contextual and temporal dynamics of PPI and explore the experience of PPI in research for all those involved. Mechanisms contributing to the routine incorporation of PPI in the research process were assessed, the impact of PPI on research processes and outcomes evaluated, and barriers and enablers to effective PPI identified.
Design
A three-staged realist evaluation drawing on Normalisation Process Theory to understand how far PPI was embedded within health-care research in six areas: diabetes mellitus, arthritis, cystic fibrosis, dementia, public health and learning disabilities. The first two stages comprised a scoping exercise and online survey to chief investigators to assess current PPI activity. The third stage consisted of case studies tracked over 18 months through interviews and document analysis. The research was conducted in four regions of England.
Participants
Non-commercial studies currently running or completed within the previous 2 years eligible for adoption on the UK Clinical Research Network portfolio. A total of 129 case study participants included researchers and PPI representatives from 22 research studies, and representatives from funding bodies and PPI networks
Establishing What Constitutes a Healthy Human Gut Microbiome: State of the Science, Regulatory Considerations, and Future Directions.
On December 17, 2018, the North American branch of the International Life Sciences Institute (ILSI North America) convened a workshop "Can We Begin to Define a Healthy Gut Microbiome Through Quantifiable Characteristics?" with >40 invited academic, government, and industry experts in Washington, DC. The workshop objectives were to 1) develop a collective expert assessment of the state of the evidence on the human gut microbiome and associated human health benefits, 2) see if there was sufficient evidence to establish measurable gut microbiome characteristics that could serve as indicators of "health," 3) identify short- and long-term research needs to fully characterize healthy gut microbiome-host relationships, and 4) publish the findings. Conclusions were as follows: 1) mechanistic links of specific changes in gut microbiome structure with function or markers of human health are not yet established; 2) it is not established if dysbiosis is a cause, consequence, or both of changes in human gut epithelial function and disease; 3) microbiome communities are highly individualized, show a high degree of interindividual variation to perturbation, and tend to be stable over years; 4) the complexity of microbiome-host interactions requires a comprehensive, multidisciplinary research agenda to elucidate relationships between gut microbiome and host health; 5) biomarkers and/or surrogate indicators of host function and pathogenic processes based on the microbiome need to be determined and validated, along with normal ranges, using approaches similar to those used to establish biomarkers and/or surrogate indicators based on host metabolic phenotypes; 6) future studies measuring responses to an exposure or intervention need to combine validated microbiome-related biomarkers and/or surrogate indicators with multiomics characterization of the microbiome; and 7) because static genetic sampling misses important short- and long-term microbiome-related dynamic changes to host health, future studies must be powered to account for inter- and intraindividual variation and should use repeated measures within individuals
Economics methods in Cochrane systematic reviews of health promotion and public health related interventions.
Peer reviewedPublisher PD
Overview of systematic reviews. Effective home support in dementia care: Components and impacts, Stage 1, psychosocial interventions for dementia.
Aim: To synthesise evidence to identify the components of effective psychosocial interventions in dementia care to inform clinical practice, policy and research. Background: With population ageing dementia represents a significant care challenge with 60% of people with dementia living at home. Design: Overview of systematic reviews with narrative summary. Data sources: Electronic searches of published systematic reviews in English using Cochrane Database of Systematic Reviews, DARE, EPPI-Centre, between September 2013 - April 2014. Review methods: Systematic reviews were appraised against Cochrane Collaboration levels of effectiveness. Components of psychosocial interventions were identified with their theoretical rationale. Findings were explored with a Patient, Public and Carer Involvement group. Results: 36 systematic reviews were included. From interventions, 14 components were identified, nine for people with dementia and five for carers, mostly undertaken in nursing/care homes. For people with dementia, there was evidence of effectiveness for cognitive stimulation and cognitive training; but less evidence for sensory stimulation, reminiscence, staff education, behavioural therapy and ADL training. For carers, there was evidence of effectiveness for education and training, psychotherapy and counselling. Conclusion: There was a lack of definitive evidence of effectiveness for most psychosocial interventions. Further studies with stronger methodology or replication of existing studies would strengthen the evidence base. Few interventions were undertaken with people with dementia and their carers living at home. Further work will investigate the extent to which components identified here are present in models of home support for people with dementia and carers and their effectiveness
Early discontinuation of endocrine therapy for breast cancer: Who is at risk in clinical practice?
Purpose: Despite evidence supporting at least five years of endocrine therapy for early breast cancer, many women discontinue therapy early. We investigated the impact of initial therapy type and specific comorbidities on discontinuation of endocrine therapy in clinical practice.
Methods
We identified women in a population-based cohort with a diagnosis of early breast cancer and an incident dispensing of anastrozole, letrozole or tamoxifen from 2003-2008 (N = 1531). Pharmacy and health service data were used to determine therapy duration, treatment for pre-existing and post-initiation comorbidities (anxiety, depression, hot flashes, musculoskeletal pain, osteoporosis, vaginal atrophy), demographic and other clinical characteristics. Time to discontinuation of initial, and any, endocrine therapy was calculated. Cox regression determined the association of different characteristics on early discontinuation.
Results
Initial endocrine therapy continued for a median of 2.2 years and any endocrine therapy for 4.8 years. Cumulative probability of discontinuing any therapy was 17% after one year and 58% by five years. Initial tamoxifen, pre-existing musculoskeletal pain and newly-treated anxiety predicted shorter initial therapy but not discontinuation of any therapy. Early discontinuation of any therapy was associated with newly-treated hot flashes (HR = 2.1, 95%CI = 1.3-3.3), not undergoing chemotherapy (HR = 1.4, 95%CI = 1.1-1.8) and not undergoing mastectomy (HR = 1.5, 95%CI = 1.2-1.8).
Conclusions
Less than half of women completed five years of endocrine therapy. Women at greatest risk of stopping any therapy early were those with newly-treated hot flashes, no initial chemotherapy, or no initial mastectomy. This suboptimal use means that the reductions in recurrence demonstrated in clinical trials may not be realised in practice
Incidence and prevalence of dementia in linked administrative health data in Saskatchewan, Canada: a retrospective cohort study.
Determining the epidemiology of dementia among the population as a whole in specific jurisdictions - including the long-term care population-is essential to providing appropriate care. The objectives of this study were to use linked administrative databases in the province of Saskatchewan to determine the 12-month incidence and prevalence of dementia for the 2012/13 period (1) among individuals aged 45 and older in the province of Saskatchewan, (2) according to age group and sex, and (3) according to diagnosis code and other case definition criteria
Quality of stepped-wedge trial reporting can be reliably assessed using an updated CONSORT::crowd-sourcing systematic review
ObjectivesThe Consolidated Standards of Reporting Trials extension for the stepped-wedge cluster randomized trial (SW-CRT) is a recently published reporting guideline for SW-CRTs. We assess the quality of reporting of a recent sample of SW-CRTs.Study Design and SettingQuality of reporting was asssessed according to the 26 items in the new guideline using a novel crowd sourcing methodology conducted independently and in duplicate, with random assignment, by 50 reviewers. We assessed reliability of the quality assessments, proposing this as a novel way to assess robustness of items in reporting guidelines.ResultsSeveral items were well reported. Some items were very poorly reported, including several items that have unique requirements for the SW-CRT, such as the rationale for use of the design, description of the design, identification and recruitment of participants within clusters, and concealment of cluster allocation (not reported in more than 50% of the reports). Agreement across items was moderate (median percentage agreement was 76% [IQR 64 to 86]). Agreement was low for several items including the description of the trial design and why trial ended or stopped for example.ConclusionsWhen reporting SW-CRTs, authors should pay particular attention to ensure clear reporting on the exact format of the design with justification, as well as how clusters and individuals were identified for inclusion in the study, and whether this was done before or after randomization of the clusters, which are crucial for risk of bias assessments. Some items, including why the trial ended, might either not be relevant to SW-CRTs or might be unclearly described in the statement
Overweight and obesity in Brazilian adolescents
OBJECTIVE: This study aimed to describe the prevalence of overweight and obesity (OW+O) among Brazilian adolescents and to identify risks for subpopulations defined according to the five country macro-regions and situation (urban-rural) of the domiciles, income, years of school attendance, age and sex.DESIGN: A nationwide home-based survey representative of the Brazilian civilian noninstitutionalized population, performed in 1989.METHODS: the sampling plans followed a stratified, multistage, probability cluster design in the National Research of Health and Nutrition sample, which collected anthropometric data of 14,455 domiciles. in all, 13,715 adolescents ranging from 10 to 19 y of age were studied. the OW + O was defined from a body mass index (BMI) equal or superior to the 85th percentile of the reference population of the NCHS. the prevalences in the different studied groups were compared using the adjusted odds ratio in logistic regression models.RESULTS: the prevalence of OW + O was of 7.7%, reaching 10.6% within the female group and 4.8% within the male group. A direct relation could be established between the socioeconomic level and OW + O. Adolescents of the most industrialized region of the country presented a risk of OW + O 1.86 (95% Cl 1.51 - 2.30) times higher than that found in the least developed region. Male youngsters who lived in urban areas were more liable (OR = 1.71, 95% Cl 1.30-2.25) to overweight than their counterparts of rural areas. the occurrence of menarche increased two and a half times (OR = 2.58, 95% CI 2.11 - 3.15) the risk of OW + O within the female group of adolescents.CONCLUSIONS: the results demonstrate a low prevalence of OW + O among Brazilian adolescents when compared with adolescents of more industrialized regions. the OW + O is twice as high within the female group, which represents a much greater difference than the one encountered in industrialized countries, probably owing to the muscular work carried out preponderantly by male adolescents of lower socioeconomic levels. Higher prevalences in subpopulations of higher socioeconomic level and of more industrialized regions show the great need for differentiated actions to control overweight and obesity in the country.Univ Fed Pelotas, Fac Nutr, BR-96010900 Pelotas, RS, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pediat, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pediat, São Paulo, BrazilWeb of Scienc
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