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1.
Nature ; 538(7626): 483-486, 2016 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-27786204

RESUMO

Binary and multiple star systems are a frequent outcome of the star formation process and as a result almost half of all stars with masses similar to that of the Sun have at least one companion star. Theoretical studies indicate that there are two main pathways that can operate concurrently to form binary/multiple star systems: large-scale fragmentation of turbulent gas cores and filaments or smaller-scale fragmentation of a massive protostellar disk due to gravitational instability. Observational evidence for turbulent fragmentation on scales of more than 1,000 astronomical units has recently emerged. Previous evidence for disk fragmentation was limited to inferences based on the separations of more-evolved pre-main sequence and protostellar multiple systems. The triple protostar system L1448 IRS3B is an ideal system with which to search for evidence of disk fragmentation as it is in an early phase of the star formation process, it is likely to be less than 150,000 years old and all of the protostars in the system are separated by less than 200 astronomical units. Here we report observations of dust and molecular gas emission that reveal a disk with a spiral structure surrounding the three protostars. Two protostars near the centre of the disk are separated by 61 astronomical units and a tertiary protostar is coincident with a spiral arm in the outer disk at a separation of 183 astronomical units. The inferred mass of the central pair of protostellar objects is approximately one solar mass, while the disk surrounding the three protostars has a total mass of around 0.30 solar masses. The tertiary protostar itself has a minimum mass of about 0.085 solar masses. We demonstrate that the disk around L1448 IRS3B appears susceptible to disk fragmentation at radii between 150 and 320 astronomical units, overlapping with the location of the tertiary protostar. This is consistent with models for a protostellar disk that has recently undergone gravitational instability, spawning one or two companion stars.

2.
Anal Biochem ; 545: 72-77, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29407179

RESUMO

Post-translational modifications are biologically important and wide-spread modulators of protein function. Although methods for detecting the presence of specific modifications are becoming established, approaches for quantifying their mol modification/mol protein stoichiometry are less well developed. Here we introduce a ratiometric, label-free, targeted liquid chromatography tandem mass spectroscopy-based method for estimating Lys and Arg methylation stoichiometry on post-translationally modified proteins. Methylated Lys and Arg were detected with limits of quantification at low fmol and with linearity extending from 20 to 5000 fmol. This level of sensitivity allowed estimation of methylation stoichiometry from microgram quantities of various proteins, including those derived from either recombinant or tissue sources. The method also disaggregated total methylation stoichiometry into its elementary mono-, di-, and tri-methylated residue components. In addition to being compatible with kinetic experiments of protein methylation, the approach will be especially useful for characterizing methylation states of proteins isolated from cells and tissues.


Assuntos
Proteínas/análise , Animais , Arginina/metabolismo , Bovinos , Cromatografia Líquida , Humanos , Lisina/metabolismo , Metilação , Proteínas/metabolismo , Espectrometria de Massas em Tandem
5.
BMC Psychiatry ; 7: 6, 2007 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-17274807

RESUMO

BACKGROUND: Bipolar Disorder (BD) is a common and severe form of mental illness characterised by repeated relapses of mania or depression. Pharmacotherapy is the main treatment currently offered, but this has only limited effectiveness. A recent Cochrane review has reported that adding psycho-social interventions that train people to recognise and manage the early warning signs of their relapses is effective in increasing time to recurrence, improving social functioning and in reducing hospitalisations. However, the review also highlights the difficulties in offering these interventions within standard mental health services due to the need for highly trained therapists and extensive input of time. There is a need to explore the potential for developing Early Warning Sign (EWS) interventions in ways that will enhance dissemination. METHODS AND DESIGN: This article describes a cluster-randomised trial to assess the feasibility of training care coordinators (CCs) in community mental health teams (CMHTs) to offer Enhanced Relapse Prevention (ERP) to people with Bipolar Disorder. CMHTs in the North West of England are randomised to either receive training in ERP and to offer this to their clients, or to continue to offer treatment as usual (TAU). The main aims of the study are (1) to determine the acceptability of the intervention, training and outcome measures (2) to assess the feasibility of the design as measured by rates of recruitment, retention, attendance and direct feedback from participants (3) to estimate the design effect of clustering for key outcome variables (4) to estimate the effect size of the impact of the intervention on outcome. In this paper we provide a rationale for the study design, briefly outline the ERP intervention, and describe in detail the study protocol. DISCUSSION: This information will be useful to researchers attempting to carry out similar feasibility assessments of clinical effectiveness trials and in particular cluster randomised controlled trials.


Assuntos
Transtorno Bipolar/terapia , Serviços Comunitários de Saúde Mental/organização & administração , Equipe de Assistência ao Paciente , Educação Médica Continuada , Humanos , Prevenção Secundária , Medicina Estatal , Resultado do Tratamento
6.
Science ; 353(6307): 1519-1521, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27708098

RESUMO

Gravitational forces are expected to excite spiral density waves in protoplanetary disks, disks of gas and dust orbiting young stars. However, previous observations that showed spiral structure were not able to probe disk midplanes, where most of the mass is concentrated and where planet formation takes place. Using the Atacama Large Millimeter/submillimeter Array, we detected a pair of trailing symmetric spiral arms in the protoplanetary disk surrounding the young star Elias 2-27. The arms extend to the disk outer regions and can be traced down to the midplane. These millimeter-wave observations also reveal an emission gap closer to the star than the spiral arms. We argue that the observed spirals trace shocks of spiral density waves in the midplane of this young disk.

7.
Psychiatr Serv ; 60(5): 702-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19411363

RESUMO

OBJECTIVE: This study examined the feasibility and effectiveness of training clinical staff in enhanced relapse prevention for people with bipolar disorder in routine services. METHODS: A cluster randomized controlled trial was conducted in North West England. This brief report focuses on the 56 staff who received enhanced relapse prevention. Staff-perceived skill in working with people with bipolar disorder to prevent relapse was assessed pretraining, posttraining, and postsupervision. Staff ratings of confidence and trainer ratings of competence for key elements of enhanced relapse prevention were made posttraining and postsupervision. Staff gave feedback on training and supervision. RESULTS: Feedback was very positive. Staff's perception of their skill increased after training and increased further after supervision. Most staff felt confident and were rated as competent in key elements of enhanced relapse prevention after training and supervision. CONCLUSIONS: An effective training and supervision package was developed. Barriers to implementation need to be addressed.


Assuntos
Transtorno Bipolar/terapia , Competência Clínica , Pessoal de Saúde/educação , Serviços de Saúde Mental/organização & administração , Inquéritos e Questionários , Ensino , Estudos de Viabilidade , Humanos , Prevenção Secundária , Ensino/métodos , Reino Unido , Recursos Humanos
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