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1.
Nature ; 498(7454): 338-41, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23698363

RESUMO

Stellar archaeology shows that massive elliptical galaxies formed rapidly about ten billion years ago with star-formation rates of above several hundred solar masses per year. Their progenitors are probably the submillimetre bright galaxies at redshifts z greater than 2. Although the mean molecular gas mass (5 × 10(10) solar masses) of the submillimetre bright galaxies can explain the formation of typical elliptical galaxies, it is inadequate to form elliptical galaxies that already have stellar masses above 2 × 10(11) solar masses at z ≈ 2. Here we report multi-wavelength high-resolution observations of a rare merger of two massive submillimetre bright galaxies at z = 2.3. The system is seen to be forming stars at a rate of 2,000 solar masses per year. The star-formation efficiency is an order of magnitude greater than that of normal galaxies, so the gas reservoir will be exhausted and star formation will be quenched in only around 200 million years. At a projected separation of 19 kiloparsecs, the two massive starbursts are about to merge and form a passive elliptical galaxy with a stellar mass of about 4 × 10(11) solar masses. We conclude that gas-rich major galaxy mergers with intense star formation can form the most massive elliptical galaxies by z ≈ 1.5.

2.
Nature ; 470(7335): 510-2, 2011 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-21326201

RESUMO

The extragalactic background light at far-infrared wavelengths comes from optically faint, dusty, star-forming galaxies in the Universe with star formation rates of a few hundred solar masses per year. These faint, submillimetre galaxies are challenging to study individually because of the relatively poor spatial resolution of far-infrared telescopes. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations. A previous attempt at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model. Here we report excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350 and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter haloes with a minimum mass, M(min), such that log(10)[M(min)/M(⊙)] = 11.5(+0.7)(-0.2) at 350 µm, where M(⊙) is the solar mass. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the Universe, and is lower than that predicted by semi-analytical models for galaxy formation.

3.
Eur J Vasc Endovasc Surg ; 50(6): 794-801, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26433594

RESUMO

OBJECTIVE: The aim was to investigate the cost-effectiveness of interventional treatment for varicose veins (VV) in the UK NHS, and to inform the national clinical guideline on VV, published by the National Institute of Health and Care Excellence. DESIGN: An economic analysis was constructed to compare the cost-effectiveness of surgery, endothermal ablation (ETA), ultrasound-guided foam sclerotherapy (UGFS), and compression stockings (CS). The analysis was based on a Markov decision model, which was developed in consultation with members of the NICE guideline development group (GDG). METHODS: The model had a 5-year time horizon, and took the perspective of the UK National Health Service. Clinical inputs were based on a network meta-analysis (NMA), informed by a systematic review of the clinical literature. Outcomes were expressed as costs and quality-adjusted life years (QALYs). RESULTS: All interventional treatments were found to be cost-effective compared with CS at a cost-effectiveness threshold of £20,000 per QALY gained. ETA was found to be the most cost-effective strategy overall, with an incremental cost-effectiveness ratio of £3,161 per QALY gained compared with UGFS. Surgery and CS were dominated by ETA. CONCLUSIONS: Interventional treatment for VV is cost-effective in the UK NHS. Specifically, based on current data, ETA is the most cost-effective treatment in people for whom it is suitable. The results of this research were used to inform recommendations within the NICE guideline on VV.


Assuntos
Técnicas de Ablação/economia , Custos de Cuidados de Saúde , Escleroterapia/economia , Meias de Compressão/economia , Ultrassonografia de Intervenção/economia , Varizes/economia , Varizes/terapia , Procedimentos Cirúrgicos Vasculares/economia , Técnicas de Ablação/efeitos adversos , Redução de Custos , Análise Custo-Benefício , Humanos , Cadeias de Markov , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Escleroterapia/efeitos adversos , Medicina Estatal/economia , Meias de Compressão/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção/efeitos adversos , Reino Unido , Varizes/complicações , Varizes/diagnóstico , Procedimentos Cirúrgicos Vasculares/efeitos adversos
4.
Phys Rev Lett ; 111(14): 141301, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24138230

RESUMO

Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a nonzero correlation at 7.7σ significance. The correlation has an amplitude and scale dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmological observable.

5.
Br J Cancer ; 106(4): 768-74, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22240788

RESUMO

BACKGROUND: The aim of this study was to investigate the hypothesis that changes in circulating microRNAs (miRs) represent potentially useful biomarkers for the diagnosis, staging and prediction of outcome in prostate cancer. METHODS: Real-time polymerase chain reaction analysis of 742 miRs was performed using plasma-derived circulating microvesicles of 78 prostate cancer patients and 28 normal control individuals to identify differentially quantified miRs. RESULTS: A total of 12 miRs were differentially quantified in prostate cancer patients compared with controls, including 9 in patients without metastases. In all, 11 miRs were present in significantly greater amounts in prostate cancer patients with metastases compared with those without metastases. The association of miR-141 and miR-375 with metastatic prostate cancer was confirmed using serum-derived exosomes and microvesicles in a separate cohort of patients with recurrent or non-recurrent disease following radical prostatectomy. An analysis of five selected miRs in urine samples found that miR-107 and miR-574-3p were quantified at significantly higher concentrations in the urine of men with prostate cancer compared with controls. CONCLUSION: These observations suggest that changes in miR concentration in prostate cancer patients may be identified by analysing various body fluids. Moreover, circulating miRs may be used to diagnose and stage prostate cancer.


Assuntos
MicroRNAs/sangue , Neoplasias da Próstata/genética , Idoso , Biomarcadores Tumorais/genética , Humanos , Masculino , MicroRNAs/urina , Metástase Neoplásica , Prognóstico , Antígeno Prostático Específico/análise , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia
13.
Psychiatry ; 39(3): 227-38, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-940897

RESUMO

Study of the interpersonal relations of emotionally disturbed children has focused largely on relationships within the family. Theories of childhood psychopathology focus almost exclusively on the parent-child triad as the etiological core of childhood emotional disturbance (Frank, 1965). Far less attention has been paid to the role of extra-familial attitudes and relationships in childhood psychopathology. In a general way, the increasing importance of the peer group during childhood has been recognized, but researchers have hardly begun to consider whether and how the manifold aspects of relationships between the emotionally disturbed and their normal peers might bear on the course of the disturbance or its refractoriness to treatment (e.g., Solomon and Wahler, 1973). Nor have they considered peer group influences on the development of the emotionally disturbed child's perception of the world and his place within it. Despite increasing recognition of the early importance of peer relations, virtually no systematic information exists on the ways in which normal children view their emotionally disturbed peers. Our purpose in this paper is to report the first of several analyses of data from an initial investigation of children's understanding of their emotionally disturbed peers. Specifically, we wish to examine whether there is evidence that normal children do, in fact, perceive as emotionally disturbed the symptomatic and distressing behavior of peers that mental health professionals would recognize as indicative of psychopathology. Further, we wish to study these issues with respect to grade and sex differences.


Assuntos
Sintomas Afetivos/diagnóstico , Grupo Associado , Percepção Social , Transtorno da Personalidade Antissocial/diagnóstico , Criança , Escolaridade , Feminino , Humanos , Relações Interpessoais , Masculino , Transtorno da Personalidade Passivo-Agressiva/diagnóstico , Transtornos Fóbicos/diagnóstico , Transtornos Psicóticos/diagnóstico , Fatores Sexuais
14.
Psychiatry ; 40(1): 48-54, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-834793

RESUMO

In a previous study, we (Marsden and Kalter, 1976) found that fourth- and sixth-grade children not only made distinctions between normal and emotionally disturbed behavior, but also were able to discriminate degrees of childhood psychopathology in a manner strikingly congruent with clinician-judges. Having assessed children's perceptions of emotional disturbance, we turned our attention to how the children might account for the development of such childhood disorders. We are aware of no previous study which has examined children's views of the etiology of emotionally disturbed behavior of their peers. Such information could shed further light on children's understanding of childhood psychopathology and might implicitly indicate what children believe are the necessary ingredients for healthy emotional development. This knowledge would be useful to mental health professionals, teachers, and parents seeking both to understand the emotionally disturbed child's place in his peer group and to convey an understanding of emotional illness to normal children.


Assuntos
Atitude , Transtornos Mentais/etiologia , Grupo Associado , Fatores Etários , Atitude Frente a Saúde , Criança , Formação de Conceito , Feminino , Humanos , Relações Interpessoais , Masculino , Fatores Sexuais
15.
J Int Bioethique ; 2(4): 255-62, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11651137

RESUMO

In vitro fertilization has become standard treatment for infertility without the benefit of thorough evaluation. Today, the effectiveness of IVF is the subject of ongoing debate, the medical and non-medical risks of treatment are not adequately understood, and there is great concern about the true costs of care both for individuals and society. Added to this debate are ethical dilemmas which have changed the way we think about reproductive rights, the family, parenthood, intergenerational responsibilities, and the legal status of children and embryos. In order to address these issues, the World Health Organization Regional Office for Europe held a meeting in June 1990 on the Place of In Vitro Fertilization in Infertility Care. The recommendations from the meeting are presented.


Assuntos
Análise Custo-Benefício , Fertilização in vitro , Infertilidade , Cooperação Internacional , Internacionalidade , Política Organizacional , Política Pública , Medição de Risco , Risco , Avaliação da Tecnologia Biomédica , Organização Mundial da Saúde , Adoção , Participação da Comunidade , Aconselhamento , Atenção à Saúde , Apoio Financeiro , Regulamentação Governamental , Alocação de Recursos para a Atenção à Saúde , Experimentação Humana , Humanos , Indústrias , Recém-Nascido , Morbidade , Mortalidade , Seleção de Pacientes , Padrões de Referência , Alocação de Recursos , Mudança Social , Controle Social Formal
16.
Phlebology ; 28 Suppl 1: 135-40, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23482549

RESUMO

BACKGROUND: Cost-effectiveness analysis (CEA) is often misperceived to be a cost-cutting exercise. The intention of CEA is not to identify and implement cheap technologies, but rather those which offer maximum health gain, subject to available funds. Such analysis is crucial for decision making in health care, as tight budget constraints mean spending in one area of healthcare displaces spending elsewhere. Therefore in order to achieve the greatest health gain for the overall population, treatments must be selected which provide the greatest health gain within the available funds. SUMMARY: The relevance of CEA in health care systems is explained, using varicose vein treatment in the UK NHS as an example. Treatment for varicose veins is often not commissioned to at a local level, most likely because it is misperceived to be a cosmetic problem. However, this view does not take into account the impact of quality of life. CEA balances costs against a quantitative measure of health related quality of life, and could therefore be used to determine whether it is cost-effective to provide varicose vein treatment. The current literature on the cost-effectiveness of varicose vein treatment is reviewed, and an overview of cost-effectiveness principles is provided. Concepts such as economic modelling, incremental cost-effectiveness ratios (ICERs), net monetary benefit (NMB) and sensitivity analysis are explained, using examples relevant to varicose veins where appropriate. CONCLUSION: This article explains how, far from cutting costs and sacrificing patient health, CEA provides a useful tool to maximise the health of the population in the face of ever tightening budget constraints. CEA could be used to compare the cost-effectiveness of the various treatment options for varicose veins, and efficiencies realised.


Assuntos
Custos de Cuidados de Saúde , Avaliação de Processos e Resultados em Cuidados de Saúde/economia , Medicina Estatal/economia , Varizes/economia , Varizes/terapia , Redução de Custos , Análise Custo-Benefício , Humanos , Modelos Econômicos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Resultado do Tratamento , Reino Unido , Varizes/psicologia
17.
Nutr Diabetes ; 3: e77, 2013 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-23797384

RESUMO

BACKGROUND: Pre-commitment strategies can encourage participants to commit to a healthy food plan and have been suggested as a potential strategy for weight loss. However, it is unclear whether such strategies are cost-effective. OBJECTIVE: To analyse whether pre-commitment interventions that facilitate healthier diets are a cost-effective approach to tackle obesity. METHODS: Effectiveness evidence was obtained from a systematic review of the literature. For interventions demonstrating a clinically significant change in weight, a Markov model was employed to simulate the long-term health and economic consequences. The review supported modelling just one intervention: grocery shopping to a predetermined list combined with standard behavioural therapy (SBT). SBT alone and do nothing were used as comparators. The target population was overweight or obese adult women. A lifetime horizon for health effects (expressed as quality-adjusted life years (QALYs)) and costs from the perspective of the UK health sector were used to calculate incremental cost-effectiveness ratios (ICERs). RESULTS: In the base case analysis, the pre-commitment strategy of shopping to a list was found to be more effective and cost saving when compared against SBT, and cost-effective when compared against 'do nothing' (ICER=£166 per QALY gained). A sensitivity analysis indicated that shopping to a list remained dominant or cost-effective under various scenarios. CONCLUSION: Our findings suggest grocery shopping to a predetermined list combined with SBT is a cost-effective means for reducing obesity and its related health conditions.

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