2,294 research outputs found
First detection of CF+ towards a high-mass protostar
We report the first detection of the J = 1 - 0 (102.6 GHz) rotational lines
of CF+ (fluoromethylidynium ion) towards CygX-N63, a young and massive
protostar of the Cygnus X region. This detection occurred as part of an
unbiased spectral survey of this object in the 0.8-3 mm range, performed with
the IRAM 30m telescope. The data were analyzed using a local thermodynamical
equilibrium model (LTE model) and a population diagram in order to derive the
column density. The line velocity (-4 km s-1) and line width (1.6 km s-1)
indicate an origin from the collapsing envelope of the protostar.
We obtain a CF+ column density of 4.10e11 cm-2. The CF+ ion is thought to be
a good tracer for C+ and assuming a ratio of 10e-6 for CF+/C+, we derive a
total number of C+ of 1.2x10e53 within the beam. There is no evidence of carbon
ionization caused by an exterior source of UV photons suggesting that the
protostar itself is the source of ionization. Ionization from the protostellar
photosphere is not efficient enough. In contrast, X-ray ionization from the
accretion shock(s) and UV ionization from outflow shocks could provide a large
enough ionizing power to explain our CF+ detection.
Surprisingly, CF+ has been detected towards a cold, massive protostar with no
sign of an external photon dissociation region (PDR), which means that the only
possibility is the existence of a significant inner source of C+. This is an
important result that opens interesting perspectives to study the early
development of ionized regions and to approach the issue of the evolution of
the inner regions of collapsing envelopes of massive protostars. The existence
of high energy radiations early in the evolution of massive protostars also has
important implications for chemical evolution of dense collapsing gas and could
trigger peculiar chemistry and early formation of a hot core.Comment: 6 page
Internamentos Compulsivos: revisão da casuística dos HUC e HIP no triénio 2006-2008.
ão obstante terem passado mais de 10 anos sobre a publicação da Lei de Saúde Mental, o intenso debate
e reflexão ocorridos não foram acompanhados por publicação, igualmente profusa, de investigação clínica
sobre a epidemiologia dos internamentos compulsivos. Os autores procuraram caracterizar o arquétipo do
doente submetido a internamento involuntário em Portugal, apreciando variáveis demográficas, clínicas e legais.
Para esse fim, conduziu-se um estudo retrospectivo dos internamentos compulsivos ocorridos entre 2006
e 2008 em dois hospitais: os Hospitais da Universidade de Coimbra (HUC) e o Hospital Infante D. Pedro –
Aveiro (HIP). Uma amostra de 384 internamentos foi recolhida e caracterizada, apresentando-se resultados
desta investigação e discussão dos dados obtidos
Efeito da época de semeadura sobre a qualidade da semente de soja no Estado de Mato Grosso.
bitstream/item/77933/1/CNPSO-PESQ.-AND.-9-86.pd
Phase-transition-like properties of double-beam optical tweezers
We report on double-beam optical tweezers that undergo previously unknown phase-transition-like behavior resulting in the formation of more optical traps than the number of beams used to create them. We classify the optical force fields which produce multiple traps for a double-beam system including the critical behavior. This effect is demonstrated experimentally in orthogonally polarized (noninterfering) dual-beam optical tweezers for a silica particle of 2.32 μm diameter. Phase transitions of multiple beam trapping systems have implications for hopping rates between traps and detection of forces between biomolecules using dual-beam optical tweezers. It is an example of a novel dynamic system with multiple states where force fields undergo a series of sign inversions as a function of parameters such as size and beam separation
Geographic and temporal population dynamics of the olive anthracnose pathogens
info:eu-repo/semantics/publishedVersio
The W43-MM1 mini-starburst ridge, a test for star formation efficiency models
Context: Star formation efficiency (SFE) theories are currently based on
statistical distributions of turbulent cloud structures and a simple model of
star formation from cores. They remain poorly tested, especially at the highest
densities. Aims: We investigate the effects of gas density on the SFE through
measurements of the core formation efficiency (CFE). With a total mass of
M, the W43-MM1 ridge is one of the most convincing
candidate precursor of starburst clusters and thus one of the best place to
investigate star formation. Methods: We used high-angular resolution maps
obtained at 3 mm and 1 mm within W43-MM1 with the IRAM Plateau de Bure
Interferometer to reveal a cluster of 11 massive dense cores (MDCs), and, one
of the most massive protostellar cores known. An Herschel column density image
provided the mass distribution of the cloud gas. We then measured the
'instantaneous' CFE and estimated the SFE and the star formation rate (SFR)
within subregions of the W43-MM1 ridge. Results: The high SFE found in the
ridge (6% enclosed in 8 pc) confirms its ability to form a
starburst cluster. There is however a clear lack of dense cores in the northern
part of the ridge, which may be currently assembling. The CFE and the SFE are
observed to increase with volume gas density while the SFR steeply decreases
with the virial parameter, . Statistical models of the SFR may
well describe the outskirts of the W43-MM1 ridge but struggle to reproduce its
inner part, which corresponds to measurements at low . It may be
that ridges do not follow the log-normal density distribution, Larson
relations, and stationary conditions forced in the statistical SFR models.Comment: 13 pages, 7 figures. Accepted by A&
Avaliação dos efeitos da osmose inversa na concentração de suco de melão e na sua qualidade final.
Suco de maçã clarificado: efeito do tratamento enzimático associado à microfiltração na qualidade do produto final.
Diversidade de homológos do gene codificador da proteína alergênica alt a 1 em isolados de Alternaria associados com aliáceas no Brasil.
No presente trabalho foi realizado um estudo da diversidade de isolados de Alternaria de aliáceas no Brasil usnado informações genéticas derivadas do gene CTAB.Resumo 1075. Edição dos resumos do 44º Congresso Brasileiro de Fitopatologia, 2011, Bento Gonçalves
Abcesso Prostático
O abcesso da próstata é actualmente uma entidade pouco frequente, resultado de uma
melhoria na terapêutica antibiótica. No entanto deve ser considerado em doentes com
factores de risco (infecções urinárias complicadas) que no decurso de um quadro infeccioso,
apresentam agravamento marcado da sintomatologia ou resposta inadequada à terapêutica.
Apresentamos um caso clínico de um doente de 47 anos com diabetes mellitus não controlada,
cujo abcesso prostático foi tratado com antibioterapia sistémica, associada a drenagem
transrectal ecodirigida
- …