RESUMO
We investigate the formation of a laser-produced magnetized jet under conditions of a varying mass ejection rate and a varying divergence of the ejected plasma flow. This is done by irradiating a solid target placed in a 20 T magnetic field with, first, a collinear precursor laser pulse (10^{12} W/cm^{2}) and, then, a main pulse (10^{13} W/cm^{2}) arriving 9-19 ns later. Varying the time delay between the two pulses is found to control the divergence of the expanding plasma, which is shown to increase the strength of and heating in the conical shock that is responsible for jet collimation. These results show that plasma collimation due to shocks against a strong magnetic field can lead to stable, astrophysically relevant jets that are sustained over time scales 100 times the laser pulse duration (i.e., >70 ns), even in the case of strong variability at the source.
RESUMO
A new measurement of the branching ratio R_{e/µ}=Γ(π^{+}âe^{+}ν+π^{+}âe^{+}νγ)/Γ(π^{+}âµ^{+}ν+π^{+}âµ^{+}νγ) resulted in R_{e/µ}^{exp}=[1.2344±0.0023(stat)±0.0019(syst)]×10^{-4}. This is in agreement with the standard model prediction and improves the test of electron-muon universality to the level of 0.1%.
RESUMO
We report new measurements of inclusive pi production from frozen-spin HD for polarized photon beams covering the Delta(1232) resonance. These provide data simultaneously on both H and D with nearly complete angular distributions of the spin-difference cross sections entering the Gerasimov-Drell-Hearn (GDH) sum rule. Recent results from Mainz and Bonn exceed the GDH prediction for the proton by 22 microb, suggesting as yet unmeasured high-energy components. Our pi0 data reveal a different angular dependence than assumed in Mainz analyses and integrate to a value that is 18 microb lower, suggesting a more rapid convergence. Our results for deuterium are somewhat lower than published data, considerably more precise, and generally lower than available calculations.
RESUMO
A search for T-violating transverse muon polarization (P(T)) in the K+-->pi(0)mu(+)nu decay was performed using kaon decays at rest. A new improved value P(T)=-0.0017+/-0.0023(stat)+/-0.0011(syst) was obtained giving an upper limit |P(T)|<0.0050. The T-violation parameter was determined to be Imxi=-0.0053+/-0.0071(stat)+/-0.0036(syst) giving an upper limit |Imxi|<0.016.
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Even as the federal government tries to prop up Medicare managed care, HMOs continue to pull out of the program. But a Centers for Medicare & Medicaid Services demonstration project aims to show that one concept of managed care can keep chronically ill patients healthier and lower overall costs. The concept, coordinated care, blends case management and disease management, giving patients the resources to manage their own care more actively. But, please, just don't call it managed care.
Assuntos
Administração de Caso , Doença Crônica/terapia , Gerenciamento Clínico , Sistemas Pré-Pagos de Saúde/organização & administração , Medicare Part C , Idoso , Centers for Medicare and Medicaid Services, U.S. , Sistemas Pré-Pagos de Saúde/economia , Humanos , Modelos Organizacionais , Projetos Piloto , Estados UnidosAssuntos
Biofilmes/crescimento & desenvolvimento , Contaminação de Equipamentos/prevenção & controle , Equipamentos e Provisões/microbiologia , Esterilização/métodos , Profissionais Controladores de Infecções , Joint Commission on Accreditation of Healthcare Organizations , Administração de Materiais no Hospital , Esterilização/normas , Estados UnidosRESUMO
OBJECTIVE: To determine the attitudes of South African general practitioners (GPs) to national health insurance (NHI), social health insurance (SHI) and other related health system reforms. DESIGN: A national survey using postal questionnaires and telephonic follow-up of non-responders. SETTING: GPs throughout South Africa. PARTICIPANTS: Four hundred and forty-three GPs were randomly selected from a national sampling frame of 6,781 GPs. MAIN OUTCOME MEASURES: Acceptance of NHI and GP preferences with regard to financing, provision, benefits, coverage and the role of GPs. MAIN RESULTS: A response rate of 82.1% was achieved. Sixty-two per cent of GPs approved of the introduction of some form of social or NHI in South Africa, while 24.1% disapproved. Approval rose to 81.6% if GPs were to maintain their independent status, e.g. own premises and working hours, to 75% if additional private top-up insurance was allowed, and to 79.9% if payment was by fee-for-service. Seventy per cent of GPs in the study stated that they had the capacity to treat more patients. The most important reason given for approving of NHI was to make health care more equitable and accessible to the majority of South Africans. A high proportion of GPs approved of increasing the level of interaction between GPs and district health authorities. CONCLUSIONS: Most GPs approved of some form of social or NHI system, provided that the system did not significantly threaten their professional autonomy or economic and financial situation.
Assuntos
Atitude do Pessoal de Saúde , Seguro Saúde/tendências , Programas Nacionais de Saúde , Médicos de Família , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Coleta de Dados/métodos , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , África do Sul , Inquéritos e QuestionáriosRESUMO
PURPOSE: To measure intraocular pressure (IOP) immediately and 25 minutes after small sutureless cataract surgery to estimate the duration of any elevation and to evaluate the relationship between supranormal pressurization and an elevated IOP 24 hours postoperatively. SETTING: Routine outpatient cataract surgery at a tertiary referral center. METHODS: Thirty-six consecutive eyes that had uneventful phacoemulsification cataract extraction were studied in a prospective fashion. Supranormal pressurization was attempted in all cases. Surgery was performed through a 3.5 mm scleral wound. RESULTS: Mean IOP dropped from 38.8 mm Hg +/- 11.4 (SD) to 19.8 +/- 5.3 mm Hg 25 minutes after the surgery (P < .0001). A subgroup of patients (n = 6) whose IOP was greater than 24 mm Hg 24 hours postoperatively had a pressure drop from 36.8 +/- 12.3 mm Hg to 23.2 +/- 6.2 mm Hg 25 minutes postoperatively (P = .051). In this subgroup, the mean 24 hour IOP then rose to 30.8 +/- 5.2 mm Hg (P = .043). Another subgroup of patients (n = 7) whose IOP was greater than 24 mm Hg at 25 minutes had a pressure drop from 46.3 +/- 8.5 mm Hg to 27.9 +/- 2.4 mm Hg (P = .0014), falling to 21.7 +/- 6.6 mm Hg at 24 hours (P = .018). CONCLUSION: These findings demonstrate the rapid decline of IOP after supranormal pressurization at the conclusion of cataract surgery. In addition, supranormal pressurization did not seem to contribute to IOP elevation at 24 hours.
Assuntos
Pressão Intraocular/fisiologia , Facoemulsificação/métodos , Idoso , Câmara Anterior , Feminino , Seguimentos , Humanos , Injeções , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Pressão , Estudos Prospectivos , Cloreto de Sódio/administração & dosagem , Resultado do TratamentoRESUMO
Health care is already feeling the fallout from the 1997 balanced budget pact. And the accord's $100 billion in Medicare cuts, spread over five years, are only beginning to take effect. H&HN looks at two especially hard-hit sectors: home health agencies and rural hospitals.
Assuntos
Agências de Assistência Domiciliar/economia , Medicare/legislação & jurisprudência , Orçamentos/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Mecanismo de Reembolso/legislação & jurisprudência , Estados UnidosAssuntos
Hospitais com Fins Lucrativos/economia , Investimentos em Saúde/tendências , Sistemas Multi-Institucionais/economia , Financiamento de Capital , Relações Comunidade-Instituição , Coleta de Dados , Setor de Assistência à Saúde/estatística & dados numéricos , Instituições Associadas de Saúde/tendências , Hospitais com Fins Lucrativos/estatística & dados numéricos , Renda/estatística & dados numéricos , Investimentos em Saúde/economia , Meio-Oeste dos Estados Unidos , Sistemas Multi-Institucionais/estatística & dados numéricos , Sudeste dos Estados UnidosAssuntos
Gastos de Capital/normas , Instituições Associadas de Saúde/economia , Hospitais com Fins Lucrativos/economia , Hospitais Filantrópicos/economia , Relações Comunidade-Instituição/economia , Defesa do Consumidor , Custos e Análise de Custo , Hospitais Filantrópicos/organização & administração , Propriedade/economia , Estados UnidosRESUMO
Hospital mergers, like Godzilla's comeback movie, promise that bulk means marketplace brawn. Yet as the dust settles, the payoff isn't always so clear. Promised efficiencies from merging duplicated programs--even shutting down entire hospitals--often fail to materialize. In fact, cutting the deal may turn out to be the easy part.