2,828 research outputs found
Superconducting and structural properties of plasma sprayed YBaCuO layers deposited on metallic substrates
The properties of plasma sprayed Y-Ba-Cu-O coatings deposited on metallic substrates are studied. Stainless steel, nickel steels and pure nickel are used as substrate. Y-Ba-Cu-O deposited on stainless steel and nickel steel reacts with the substrate. This interaction can be suppressed by using an yttria-stabilized zirconia (YsZ) diffusion barrier. However, after heat treatment the Y-Ba-Cu-O layers on YsZ show cracks perpendicular to the surface. As a result the critical current density is very low. The best results are obtained for Y-Ba-Cu-O deposited on pure nickel; here no cracks perpendicular to the surface are observed. The critical current increases with the anneal temperature but annealing for longer than 10 h does not seem to improve the superconducting properties any further
Business Valuation of Natural Capital; learning by doing
Businesses are starting to take an interest in the natural capital agenda but much more work is needed to map their impacts and dependence on ecosystem services. Business greening organisations argue that such work has the potential to engage influential stakeholders in achieving sustainable outcomes (WBCSD, 2011; Cranston et al 2015). However, the economic valuation of ecosystem services/natural capital has also received criticism from sections of the academic community (e.g. Redford and Adams 2009; Gomez-Baggethun and Ruiz-Perez 2011) and the press (e.g. Monbiot 2014). Such criticism can be helpful in identifying potential pitfalls and areas that may require wider involvement and engagement of stakeholders, further thought and development of methods and policies
ASAS/WHO ICF Core Sets for ankylosing spondylitis (AS): how to classify the impact of AS on functioning and health
Objective: To report on the results of a standardised consensus process agreeing on concepts typical and/or relevant when classifying functioning and health in patients with ankylosing spondylitis (AS) based on the International Classification of Functioning and Health (ICF).Methods: Experts in AS from different professional and geographical backgrounds attended a consensus conference and were divided into three working groups. Rheumatologists were selected from members of the Assessment of SpondyloArthritis international Society (ASAS). Other health professionals were recommended by ASAS members. The aim was to compose three working groups with five to seven participants to allow everybody's contribution in the discussions. Experts selected ICF categories that were considered typical and/or relevant for AS during a standardised consensus process by integrating evidence from preceding studies in alternating working group and plenary discussions. A Comprehensive ICF Core Set was selected for the comprehensive classification of functioning and a Brief ICF Core Set for application in trials.Results: The conference was attended by 19 experts from 12 countries. Eighty categories were included in the Comprehensive Core Set, which included 23 Body functions, 19 Body structures, 24 Activities and participation and 14 Environmental factors. Nineteen categories were selected for the Brief Core Set, which included 6 Body functions, 4 Body structures, 7 Activities and participation and 2 Environmental factors.Conclusion: The Comprehensive and Brief ICF Core Sets for AS are now available and aim to represent the external reference to define consequences of AS on functioning
Landscape disruption or just a lack of economic benefits? Exploring factors behind the negative perceptions of wind turbines
Road Blocks or Building Blocks?:A Qualitative Study on Challenges and Resilience in Romantic Relationships of Youth Exposed to Family Violence
Romantic relationships are an important part of many people’s lives and at least partly shaped by experiences during childhood. Youth exposed to family violence during childhood are more likely to experience difficulties in their later romantic relationships. However, a more holistic perspective on the romantic relationships of youth with a history of family violence is lacking. Using both theoretical and inductive thematic analysis, this qualitative study explored challenges as well as positive experiences within romantic relationships of youth exposed to family violence during childhood. In-depth individual interviews were conducted with 18 youth aged between 16 and 20 years, who were reported to child protection services. The narratives reflected that youth experienced challenges related to support, connection, trust, boundary setting, emotion regulation and conflict resolution. Furthermore, family violence during childhood seemed to be important in the emergence of these challenges, consistent with theoretical mechanisms described in observational learning theory and attachment theory. However, youth also described positive experiences in their romantic relationships and demonstrated an ability to learn from others (e.g., their current romantic partner) how to communicate effectively or solve problems. Therefore, with the right social or professional support, at-risk youth may be able to overcome these challenges.</p
Road Blocks or Building Blocks?:A Qualitative Study on Challenges and Resilience in Romantic Relationships of Youth Exposed to Family Violence
Romantic relationships are an important part of many people’s lives and at least partly shaped by experiences during childhood. Youth exposed to family violence during childhood are more likely to experience difficulties in their later romantic relationships. However, a more holistic perspective on the romantic relationships of youth with a history of family violence is lacking. Using both theoretical and inductive thematic analysis, this qualitative study explored challenges as well as positive experiences within romantic relationships of youth exposed to family violence during childhood. In-depth individual interviews were conducted with 18 youth aged between 16 and 20 years, who were reported to child protection services. The narratives reflected that youth experienced challenges related to support, connection, trust, boundary setting, emotion regulation and conflict resolution. Furthermore, family violence during childhood seemed to be important in the emergence of these challenges, consistent with theoretical mechanisms described in observational learning theory and attachment theory. However, youth also described positive experiences in their romantic relationships and demonstrated an ability to learn from others (e.g., their current romantic partner) how to communicate effectively or solve problems. Therefore, with the right social or professional support, at-risk youth may be able to overcome these challenges.</p
Tuberculosis Drug Resistance and Outcomes among Tuberculosis Inpatients in Lilongwe, Malawi
Setting/Objective: We evaluated clinical characteristics, yield of solid vs. liquid culture, polymerase chain reaction (PCR)-based drug-resistance profiles, and clinical outcomes of tuberculosis (TB) inpatients in Lilongwe, Malawi.Design: We enrolled adult patients admitted to the Bwaila TB Ward from Jan-Aug/2010. Evaluations included questionnaires, clinical exam, chest radiograph, HIV status, CD4 lymphocyte count, plasma HIVRNA and sputum analysis including Auramine-O stain, Lowenstein-Jensen (LJ) and Mycobacterial Growth Indicator Tube (MGIT) culture, and susceptibility testing using the HAIN GenoType® MTBDRplus.Results: Eighty-eight patients were enrolled (88% re-treatment, 42% smear positive, 93% pulmonary TB, 74% HIV co-infected). At baseline, 44/88 (50%) MGIT and 28 (32%) LJ cultures were positive with a mean time to positivity of 12.1 (Range 1-42) and 21.5 (Range 7-58) days, respectively. Four percent (3/77) of retreatment patients or 8% of the 38 MGIT+ PCR-confirmed retreatment cases had multi-drug resistant tuberculosis (MDR TB). One MDR TB patient was smear negative and only one MDR patient was identified with LJ. Lower mean hemoglobin at admission was associated with mortality (10.5 vs. 7.5; p<0.01; CI 101 9.8-11.0).Conclusions: The MDR TB burden among the retreatment population in Lilongwe, Malawi is similar to regional estimates by the WHO (7.7% 95% CI 0-18.1). MDR TB patients are not routinely identified with sputum smear or LJ, suggesting more efficient technology should be adopted
Dissecting magnetar variability with Bayesian hierarchical models
Neutron stars are a prime laboratory for testing physical processes under
conditions of strong gravity, high density, and extreme magnetic fields. Among
the zoo of neutron star phenomena, magnetars stand out for their bursting
behaviour, ranging from extremely bright, rare giant flares to numerous, less
energetic recurrent bursts. The exact trigger and emission mechanisms for these
bursts are not known; favoured models involve either a crust fracture and
subsequent energy release into the magnetosphere, or explosive reconnection of
magnetic field lines. In the absence of a predictive model, understanding the
physical processes responsible for magnetar burst variability is difficult.
Here, we develop an empirical model that decomposes magnetar bursts into a
superposition of small spike-like features with a simple functional form, where
the number of model components is itself part of the inference problem. The
cascades of spikes that we model might be formed by avalanches of reconnection,
or crust rupture aftershocks. Using Markov Chain Monte Carlo (MCMC) sampling
augmented with reversible jumps between models with different numbers of
parameters, we characterise the posterior distributions of the model parameters
and the number of components per burst. We relate these model parameters to
physical quantities in the system, and show for the first time that the
variability within a burst does not conform to predictions from ideas of
self-organised criticality. We also examine how well the properties of the
spikes fit the predictions of simplified cascade models for the different
trigger mechanisms.Comment: accepted for publication in The Astrophysical Journal; code available
at https://bitbucket.org/dhuppenkothen/magnetron, data products at
http://figshare.com/articles/SGR_J1550_5418_magnetron_data/129242
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