484 research outputs found
Nebular models of sub-chandrasekhar mass type ia supernovae: Clues to the origin of ca-rich transients
We use non-local thermal equilibrium radiative transport modeling to examine observational signatures of sub- Chandrasekhar mass double detonation explosions in the nebular phase. Results range from spectra that look like typical and subluminous Type Ia supernovae (SNe) for higher mass progenitors to spectra that look like Ca-rich transients for lower mass progenitors. This ignition mechanism produces an inherent relationship between emission features and the progenitor mass as the ratio of the nebular [Ca II]/[Fe III] emission lines increases with decreasing white dwarf mass. Examining the [Ca II]/[Fe III] nebular line ratio in a sample of observed SNe we find further evidence for the two distinct classes of SNe Ia identified in Polin et al. by their relationship between Si II velocity and B-band magnitude, both at time of peak brightness. This suggests that SNe Ia arise from more than one progenitor channel, and provides an empirical method for classifying events based on their physical origin. Furthermore, we provide insight to the mysterious origin of Ca-rich transients. Low-mass double detonation models with only a small mass fraction of Ca (1%) produce nebular spectra that cool primarily through forbidden [Ca II] emission
Gravitational Wave Hotspots: Ranking Potential Locations of Single-Source Gravitational Wave Emission
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COPe-support - a multi-component digital intervention for family carers for people affected by psychosis: study protocol for a randomized controlled trial.
BACKGROUND: Psychosis often causes significant distress and impacts not only in the individuals, but also those close to them. Many relatives and friends ('carers') provide long-term support and need resources to assist them. We have co-produced a digital mental health intervention called COPe-support (Carers fOr People with Psychosis e-support) to provide carers with flexible access to high quality psychoeducation and interactive support from experts and peers. This study evaluates the effectiveness of COPe-support to promote mental wellbeing and caregiving experiences in carers. METHODS: This study is a single-blind, parallel arm, individually randomized controlled trial (RCT) comparing COPe-support, with attention control. Both groups continue to receive usual care. COPe-support provides interactive web-based psychoeducation on psychosis-related issues, wellbeing-promotion and network support through forums. The attention-control is a non-interactive online information resource pack. Carers living in England are eligible if they provide at least weekly support to a family member or close friend affected by psychosis, and use internet communication (including emails) daily. All trial procedures are run online, including collection of outcome measurements which participants will directly input into our secure platform. Following baseline assessment, a web-based randomization system will be used to allocate 360 carers to either arm. Participants have unlimited access to the allocated condition for 40 weeks. Data collection is at three time points (10, 20, and 40 weeks after randomization). Analyses will be conducted by trial statisticians blinded to allocation. The primary outcome is mental wellbeing measured by Warwick Edinburgh Mental Wellbeing Scale (WEMWBS), at 20 weeks. As well as an intention-to-treat analysis, a complier average causal effect (CACE) analysis will be conducted to estimate the intervention effect in participants who have accessed COPe-support content twice or more. The secondary objectives and analysis will examine other health and caregiving-related outcomes and explore mechanisms. In a process evaluation, we will interview 20% of the intervention arm participants regarding the acceptability of COPe-support. We will explore in detail participants' usage patterns. DISCUSSION: The results of this trial will provide valuable information about the effectiveness of COPe-support in promoting wellbeing and caregiving experiences in carers. TRIAL REGISTRATION: The RCT is registered with the Current Controlled Trials registration (ISRCTN 89563420, registration date: 02/03/2018)
Dynamic critical behavior of the Chayes-Machta-Swendsen-Wang algorithm
We study the dynamic critical behavior of the Chayes-Machta dynamics for the
Fortuin-Kasteleyn random-cluster model, which generalizes the Swendsen-Wang
dynamics for the q-state Potts model to noninteger q, in two and three spatial
dimensions, by Monte Carlo simulation. We show that the Li-Sokal bound z \ge
\alpha/\nu is close to but probably not sharp in d=2, and is far from sharp in
d=3, for all q. The conjecture z \ge \beta/\nu is false (for some values of q)
in both d=2 and d=3.Comment: Revtex4, 4 pages including 4 figure
Persepsi Penghuni terhadap Kenyamanan Beraktivitas di Ruang Terbuka Perumahan
A comfort open space has a function and a huge influence in housing because it becomes a means of activity throughout the housing dwellers. Debang Housing Taman Sari Medan is one of housing in Kecamatan Medan Selayang which has open space. The purpose of this research is to know the perception of occupant to the comfort of open space. There are several convenience factors that are used as indicators in research such as Circulation, Climate, Noise, Smell, Shape, Safety, Cleanliness, and Beauty. The research was done through qualitative descriptive analysis, where the data collection technique used questionnaire from the population and the specified sample. The process of collecting data, sampling technique until the criteria of research become an important process of research method. This study shows if the perception of occupants of the comfort of open space of housing Debang Taman Sari Medan is quite comfortable and needed supporting facilities for park users
Kajian Tentang Jalur Pedestrian Berdasarkan Aspek Kenyamanan
Pedestrian path is a space for pedestrian activities to carry out activities and to provide services topedestrians so that it can improve the smoothness, safety, and comfort of pedestrians when crossing it. Infact the pedestrian paths that exist are mostly unable to meet the passions of pedestrians. The length oftime pedestrians are less noticed, which should be passed comfortably suddenly blocked by poles, trees,trash cans, stops, and traffic signs because the placement is not adjusted to the place so that thecirculation of road users becomes narrow and disturbed. This study aims to find aspects of comfort in thepedestrian path. Research uses quantative methods. This study found that some of the pedestrian path inthe study area were comfortable, but some were uncomfortable
Direct measurement of the flow field around swimming microorganisms
Swimming microorganisms create flows that influence their mutual interactions
and modify the rheology of their suspensions. While extensively studied
theoretically, these flows have not been measured in detail around any
freely-swimming microorganism. We report such measurements for the microphytes
Volvox carteri and Chlamydomonas reinhardtii. The minute ~0.3% density excess
of V. carteri over water leads to a strongly dominant Stokeslet contribution,
with the widely-assumed stresslet flow only a correction to the subleading
source dipole term. This implies that suspensions of V. carteri have features
similar to suspensions of sedimenting particles. The flow in the region around
C. reinhardtii where significant hydrodynamic interaction is likely to occur
differs qualitatively from a "puller" stresslet, and can be described by a
simple three-Stokeslet model.Comment: 4 pages, 4 figures, accepted for publication in PR
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Co-producing and evaluating an innovative eHealth intervention for family carers of people with psychosis - the EFFIP Project (E-support for Families & Friends of Individuals affected by Psychosis)
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Co-producing and evaluating an innovative eHealth intervention for family carers of people with psychosis – the EFFIP Project
Paper presented at European Academy of Nursing Science Summer Conference, 2019, 10-11 July, Lisbon, Portugal
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