988 resultados para Search procedures
Resumo:
Background: Many deep-sea benthic animals occur in patchy distributions separated by thousands of kilometres, yet because deep-sea habitats are remote, little is known about their larval dispersal. Our novel method simulates dispersal by combining data from the Argo array of autonomous oceanographic probes, deep-sea ecological surveys, and comparative invertebrate physiology. The predicted particle tracks allow quantitative, testable predictions about the dispersal of benthic invertebrate larvae in the south-west Pacific. Principal Findings: In a test case presented here, using non-feeding, non-swimming (lecithotrophic trochophore) larvae of polyplacophoran molluscs (chitons), we show that the likely dispersal pathways in a single generation are significantly shorter than the distances between the three known population centres in our study region. The large-scale density of chiton populations throughout our study region is potentially much greater than present survey data suggest, with intermediate ‘stepping stone’ populations yet to be discovered. Conclusions/Significance: We present a new method that is broadly applicable to studies of the dispersal of deep-sea organisms. This test case demonstrates the power and potential applications of our new method, in generating quantitative, testable hypotheses at multiple levels to solve the mismatch between observed and expected distributions: probabilistic predictions of locations of intermediate populations, potential alternative dispersal mechanisms, and expected population genetic structure. The global Argo data have never previously been used to address benthic biology, and our method can be applied to any non-swimming larvae of the deep-sea, giving information upon dispersal corridors and population densities in habitats that remain intrinsically difficult to assess.
Resumo:
Background
Restorative justice is “a process whereby parties with a stake in a specific offence resolve collectively how to deal with the aftermath of the offence and its implications for the future” (Marshall 2003). Despite the increasing use of restorative justice programmes as an alternative to court proceedings, no systematic review has been undertaken of the available evidence on the effectiveness of these programmes with young offenders. Recidivism in young offenders is a particularly worrying problem, as recent surveys have indicated
the frequency of re-offences for young offenders has ranged from 40.2% in 2000 to 37.8% in 2007 (Ministry of Justice 2009)
Objectives
To evaluate the effects of restorative justice conferencing programmes for reducing recidivism in young offenders.
Search methods
We searched the following databases up to May 2012: CENTRAL, 2012 Issue 5, MEDLINE (1978 to current), Bibliography of Nordic Criminology (1999 to current), Index to Theses (1716 to current), PsycINFO (1887 to current), Social Sciences Citation Index (1970 to current), Sociological Abstracts (1952 to current), Social Care Online (1985 to current), Restorative Justice Online (1975 to current), Scopus (1823 to current), Science Direct (1823 to current), LILACS (1982 to current), ERIC (1966 to current), Restorative Justice Online (4May 2012),WorldCat (9May 2012), ClinicalTrials.gov (19May 2012) and ICTRP (19May 2012). ASSIA,National Criminal Justice Reference Service and Social Services Abstracts were searched up to May 2011. Relevant bibliographies, conference programmes and journals were also searched.
Selection criteria
Randomised controlled trials (RCTs) or quasi-RCTs of restorative justice conferencing versus management as usual, in young offenders.
Data collection and analysis
Two authors independently assessed the risk of bias of included trials and extracted the data. Where necessary, original investigators were contacted to obtain missing information.
Main results
Four trials including a total of 1447 young offenders were included in the review. Results failed to find a significant effect for restorative justice conferencing over normal court procedures for any of the main analyses, including number re-arrested (odds ratio (OR) 1.00, 95% confidence interval (CI) 0.59 to 1.71; P = 0.99), monthly rate of reoffending (standardised mean difference (SMD) -0.06, 95% CI -0.28 to 0.16; P = 0.61), young person’s remorse following conference (OR 1.73, 95% CI 0.97 to 3.10; P = 0.06), young person’s recognition of wrongdoing following conference (OR 1.97, 95% CI 0.81 to 4.80; P = 0.14), young person’s self-perception following conference (OR 0.95, 95% CI 0.55 to 1.63; P = 0.85), young person’s satisfaction following conference (OR 0.42, 95% CI 0.04 to 4.07; P = 0.45) and victim’s satisfaction following conference (OR 4.05, 95%CI 0.56 to 29.04; P = 0.16). A small number of sensitivity analyses did indicate significant effects, although all are to be interpreted with caution.
Authors’ conclusions
There is currently a lack of high quality evidence regarding the effectiveness of restorative justice conferencing for young offenders. Caution is urged in interpreting the results of this review considering the small number of included studies, subsequent low power and high risk of bias. The effects may potentially be more evident for victims than offenders. The need for further research in this area is highlighted.
Resumo:
We investigate if the super-saturation phenomenon observed at X-ray wavelengths for the corona exists in the chromosphere for rapidly rotating late-type stars. Moderate resolution optical spectra of fast-rotating EUV- and X-ray-selected late-type stars were obtained. Stars in a Per were observed in the northern hemisphere with the Isaac Newton 2.5 m telescope and Intermediate Dispersion Spectrograph. Selected objects from IC 2391 and IC 2602 were observed in the southern hemisphere with the Blanco 4 m telescope and R-C spectrograph at CTIO. Ca II H and K fluxes were measured for all stars in our sample. We find the saturation level for Ca II K at log (L CaK/L bol) = -4.08. The Ca II K flux does not show a decrease as a function of increased rotational velocity or smaller Rossby number as observed in the X-ray. This lack of "super-saturation" supports the idea of coronal stripping as the cause of saturation and super-saturation in stellar chromospheres and coronae, but the detailed underlying mechanism is still under investigation.
Resumo:
Images of the site of the Type Ic supernova (SN) 2002ap taken before explosion were analysed previously by Smartt et al. We have uncovered new unpublished, archival pre-explosion images from the Canada-France-Hawaii Telescope (CFHT) that are vastly superior in depth and image quality. In this paper we present a further search for the progenitor star of this unusual Type Ic SN. Aligning high-resolution Hubble Space Telescope observations of the SN itself with the archival CFHT images allowed us to pinpoint the location of the progenitor site on the groundbased observations. We find that a source visible in the B- and R-band pre-explosion images close to the position of the SN is (1) not coincident with the SN position within the uncertainties of our relative astrometry and (2) is still visible similar to 4.7-yr post-explosion in late-time observations taken with the William Herschel Telescope. We therefore conclude that it is not the progenitor of SN 2002ap. We derived absolute limiting magnitudes for the progenitor of M-B >= -4.2 +/- 0.5 and M-R >= -5.1 +/- 0.5. These are the deepest limits yet placed on a Type Ic SN progenitor. We rule out all massive stars with initial masses greater than 7-8 M-circle dot (the lower mass limit for stars to undergo core collapse) that have not evolved to become Wolf-Rayet stars. This is consistent with the prediction that Type Ic SNe should result from the explosions of Wolf-Rayet stars. Comparing our luminosity limits with stellar models of single stars at appropriate metallicity (Z = 0.008) and with standard mass-loss rates, we find no model that produces a Wolf-Rayet star of low enough mass and luminosity to be classed as a viable progenitor. Models with twice the standard mass-loss rates provide possible single star progenitors but all are initially more massive than 30-40 M-circle dot. We conclude that any single star progenitor must have experienced at least twice the standard mass-loss rates, been initially more massive than 30-40 M-circle dot and exploded as a Wolf-Rayet star of final mass 10-12 M-circle dot. Alternatively a progenitor star of lower initial mass may have evolved in an interacting binary system. Mazzali et al. propose such a binary scenario for the progenitor of SN 2002ap in which a star of initial mass 15-20 M-circle dot is stripped by its binary companion, becoming a 5 M-circle dot Wolf-Rayet star prior to explosion. We constrain any possible binary companion to a main-sequence star of
Resumo:
An automated search is carried out for microlensing events using a catalogue of 44 554 variable superpixel light curves derived from our 3-yr monitoring programme of M31. Each step of our candidate selection is objective and reproducible by a computer. Our search is unrestricted, in the sense that it has no explicit time-scale cut. So, it must overcome the awkward problem of distinguishing long time-scale microlensing events from long-period stellar variables.
Resumo:
We have begun a search for early-type stars towards the galactic centre which are potentially young objects situated within the inner few kiloparsecs of the disk. U and V (or I) band photographic photometry from the UK Schmidt Telescope has been obtained to identify the bluest candidates in nineteen Schmidt fields (centred close to the galactic centre). We have spectroscopically observed these targets for three fields with the FLAIR multi-fibre system to determine their spectral types. In particular; ten early B-type stars have been identified and equivalent width measurements of their Balmer and HeI lines have been used to estimate atmospheric parameters. These early-type objects have magnitudes in the range 11.5 less than or equal to V less than or equal to 16.0, and our best estimates of their distance (given probable highly variable reddening in this direction together with errors in the plate photometry) suggest that some of them originated close to (i.e R-g
Resumo:
Purpose
The increasing impact and costs of long term sickness absence have been well documented. However, the diversity and complexity of interventions and of the contexts in which these take place makes a traditional review problematic. Therefore, we undertook a systematic realist review to identify the dominant programme theories underlying best practice, to assess the evidence for these theories, and to throw light on important enabling or disabling contextual factors.
Method
A search of the scholarly literature from 1950 to 2011 identified 5,576 articles, of which 269 formed the basis of the review.
Results
We found that the dominant programme theories in relation to effective management related to: early intervention or referral by employers; having proactive organisational procedures; good communication and cooperation between stakeholders; and workplace-based occupational rehabilitation. Significant contextual factors were identified as the level of support for interventions from top management, the size and structure of the organisation, the level of financial and organisational investment in the management of long-term sickness absence, and the quality of relationships between managers and staff.
Conclusions
Consequently, those with responsibility for managing absence should bear in mind the contextual factors that are likely to have an impact on interventions, and do what they can to ensure stakeholders have at least a mutual understanding (if not a common purpose) in relation to their perceptions of interventions, goals, culture and practice in the management of long term sickness absence.
Resumo:
Contemporary settled democracies, including the United States, England and Wales and Ireland, have witnessed a string of high profile cases of institutional child abuse in both church and state settings. Set against the broader literature on transitional justice, this analysis argues that there are significant barriers to truth recovery within the particular context of historical institutional abuse by the clergy in the Republic of Ireland. In the main, I argue that the frameworks of the inquiries and commissions into historical institutional child abuse are not conducive to truth recovery or the search for justice in dealing with the legacy of an abusive past. It is the church-state relationship which makes the Irish situation noteworthy and unique. The Catholic Church and child care institutions are especially self-protective, secretive and closed by nature and strongly discourage the drawing of attention to any deficiencies in organisational procedures. The nature of the public inquiry process also means that there is often a rather linear focus on accountability and apportioning blame. Collectively, such difficulties inhibit fuller systemic investigation of the veracity of what actually happened and, in turn, meaningful modification of child care policies. The article concludes by offering some thoughts on implications for transitional justice discourses more broadly as well as the residual issues for Ireland and other settled democracies in terms of moving on from the legacy of institutional child abuse.
Resumo:
A bit-level systolic array system for performing a binary tree vector quantization (VQ) codebook search is described. This is based on a highly regular VLSI building block circuit. The system in question exhibits a very high data rate suitable for a range of real-time applications. A technique is described which reduces the storage requirements of such a system by 50%, with a corresponding decrease in hardware complexity.