2,984 research outputs found
Remote Sensing and Control of Phase Qubits
We demonstrate a remote sensing design of phase qubits by separating the
control and readout circuits from the qubit loop. This design improves
measurement reliability because the control readout chip can be fabricated
using more robust materials and can be reused to test different qubit chips.
Typical qubit measurements such as Rabi oscillations, spectroscopy, and
excited-state energy relaxation are presented.Comment: 3 pages, 4 figure
Recommended from our members
The connection between galaxy environment and the luminosity function slopes of star-forming regions
We present the first study of GALEX far ultra-violet (FUV) luminosity
functions of individual star-forming regions within a sample of 258 nearby
galaxies spanning a large range in total stellar mass and star formation
properties. We identify ~65,000 star-forming regions (i.e., FUV sources),
measure each galaxy's luminosity function, and characterize the relationships
between the luminosity function slope (alpha) and several global galaxy
properties. A final sample of 82 galaxies with reliable luminosity functions
are used to define these relationships and represent the largest sample of
galaxies with the largest range of galaxy properties used to study the
connection between luminosity function properties and galaxy environment. We
find that alpha correlates with global star formation properties, where
galaxies with higher star formation rates and star formation rate densities
(Sigma_SFR) tend to have flatter luminosity function slopes. In addition, we
find that neither stochastic sampling of the luminosity function in galaxies
with low-number statistics nor the effects of blending due to distance can
fully account for these trends. We hypothesize that the flatter slopes in high
Sigma_SFR galaxies is due to higher gas densities and higher star formation
efficiencies which result in proportionally greater numbers of bright
star-forming regions. Finally, we create a composite luminosity function
composed of star-forming regions from many galaxies and find a break in the
luminosity function at brighter luminosities. However, we find that this break
is an artifact of varying detection limits for galaxies at different distances.Science and Technology Facilities CouncilThis is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/mnras/stw169
Analysis of galaxy SEDs from far-UV to far-IR with CIGALE: Studying a SINGS test sample
Photometric data of galaxies covering the rest-frame wavelength range from
far-UV to far-IR make it possible to derive galaxy properties with a high
reliability by fitting the attenuated stellar emission and the related dust
emission at the same time. For this purpose we wrote the code CIGALE (Code
Investigating GALaxy Emission) that uses model spectra composed of the Maraston
(or PEGASE) stellar population models, synthetic attenuation functions based on
a modified Calzetti law, spectral line templates, the Dale & Helou dust
emission models, and optional spectral templates of obscured AGN. Depending on
the input redshifts, filter fluxes are computed for the model set and compared
to the galaxy photometry by carrying out a Bayesian-like analysis. CIGALE was
tested by analysing 39 nearby galaxies selected from SINGS. The reliability of
the different model parameters was evaluated by studying the resulting
expectation values and their standard deviations in relation to the input model
grid. Moreover, the influence of the filter set and the quality of photometric
data on the code results was estimated. For up to 17 filters between 0.15 and
160 mum, we find robust results for the mass, star formation rate, effective
age of the stellar population at 4000 A, bolometric luminosity, luminosity
absorbed by dust, and attenuation in the far-UV. A study of the mutual
relations between the reliable properties confirms the dependence of star
formation activity on morphology in the local Universe and indicates a
significant drop in this activity at about 10^11 M_sol towards higher total
stellar masses. The dustiest sample galaxies are present in the same mass
range. [abridged]Comment: 22 pages, 21 figures, accepted for publication in A&
Association between polymorphism SLC6A3 3 UTR VNTR and response to treatment of nicotine dependence
Objective: To evaluate the association between response to treatment of nicotine dependence with bupropion and the presence of the polymorphism SLC6A3 3 UTR VNTR, in the gene that codifies the dopaminergic transporter. Method: A hundred patients were treated in the Nicotine Dependence Outpatient Clinic of the Institute of Psychiatry, University of São Paulo Medical School. All patients were male, diagnosed as nicotine dependents and had no other diseases. All received bupropion until 300 mg a day for 12 weeks, combined with cognitive-behavioral group therapy. The Fagerström Scale was applied at the beginning and at the end of treatment. Cigarette cessation was evaluated in the last week of treatment and one month later. Patients had 10 ml blood extracted and genotiped for SLC6A3 3 UTR VNTR polymorphism. Results: There was no association between cigarettes cessation and the presence of polymorphism. Conclusion: More studies are needed to assess whether the presence of polymorphism SLC6A3 3 UTR VNTR could be associated with a better response to treatment of nicotine dependence.Objetivo: Avaliar a associação entre a resposta ao tratamento da dependência de nicotina com bupropiona e a presença do polimorfismo SLC6A3 3 UTR VNTR, localizado no gene que codifica o transportador dopaminérgico. Método: Foram acompanhados no Ambulatório de Tabagismo do Instituto de Psiquiatria da Faculdade de Medicina da USP 100 pacientes do sexo masculino com diagnóstico de dependência de nicotina, sem outras patologias. Todos receberam bupropiona até 300 mg ao dia por 12 semanas, associada à terapia cognitivo-comportamental em grupo. A Escala de Fagerström foi aplicada no inÃcio e no final do tratamento, e avaliou-se a parada do uso de cigarros na última semana de tratamento e um mês após. Os pacientes tiveram 10 ml de sangue colhidos e genotipados para a existência do polimorfismo SLC6A3 3 UTR VNTR. Resultados: Não foi encontrada associação entre cessação do uso de cigarro e presença do polimorfismo. Conclusão: São necessários mais estudos para avaliar se a presença do polimorfismo SLC6A3 3 UTR VNTR estaria relacionada à melhor resposta ao tratamento da dependência de nicotina.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade de São Paulo Faculdade de Medicina Instituto de PsiquiatriaUniversidade Federal de São Paulo (UNIFESP) Faculdade de Medicina Departamento de GinecologiaUSP Faculdade de Medicina Departamento de PsiquiatriaUNIFESP, Faculdade de Medicina Depto. de GinecologiaSciEL
The origin of [C II] 157 μm emission in a five-component interstellar medium : the case of NGC 3184 and NGC 628
With its relatively low ionization potential, C+ can be found throughout the interstellar medium (ISM) and provides one of the main cooling channels of the ISM via the [C II] 157 mu m emission. While the strength of the [C II] line correlates with the star formation rate, the contributions of the various gas phases to the [C II] emission on galactic scales are not well established. In this study we establish an empirical multi-component model of the ISM, including dense H II regions, dense photon dissociation regions (PDRs), the warm ionized medium (WIM), low density and G(0). surfaces of molecular clouds (SfMCs), and the cold neutral medium (CNM). We test our model on ten luminous regions within the two nearby galaxies NGC 3184 and NGC 628. on angular scales of 500-600 pc. Both galaxies are part of the Herschel. key program. KINGFISH,. and are complemented by a large set of ancillary ground-and space-based data. The five modeled phases together reproduce the observed [C II] emission quite well, overpredicting the total flux slightly (about 45%) averaged over all regions. We find that dense PDRs are the dominating component, contributing 68% of the [C II] flux on average, followed by the WIM and the SfMCs, with mean contributions of about half of the contribution from dense PDRs, each. CNM and dense H II regions are only minor contributors with less than 5% each. These estimates are averaged over the selected regions, but the relative contributions of the various phases to the [C II] flux vary significantly between these regions
Modeling the Effects of Star Formation Histories on Halpha and Ultra-Violet Fluxes in Nearby Dwarf Galaxies
We consider the effects of non-constant star formation histories (SFHs) on
Halpha and GALEX far ultra-violet (FUV) star formation rate (SFR) indicators.
Under the assumption of a fully populated Chabrier IMF, we compare the
distribution of Halpha-to-FUV flux ratios from ~ 1500 simple, periodic model
SFHs with observations of 185 galaxies from the Spitzer Local Volume Legacy
survey. We find a set of SFH models that are well matched to the data, such
that more massive galaxies are best characterized by nearly constant SFHs,
while low mass systems experience bursts amplitudes of ~ 30 (i.e., an increase
in the SFR by a factor of 30 over the SFR during the inter-burst period), burst
durations of tens of Myr, and periods of ~ 250 Myr; these SFHs are broadly
consistent with the increased stochastic star formation expected in systems
with lower SFRs. We analyze the predicted temporal evolution of galaxy stellar
mass, R-band surface brightness, Halpha-derived SFR, and blue luminosity, and
find that they provide a reasonable match to observed flux distributions. We
find that our model SFHs are generally able to reproduce both the observed
systematic decline and increased scatter in Halpha-to-FUV ratios toward low
mass systems, without invoking other physical mechanisms. We also compare our
predictions with those from the Integrated Galactic IMF theory with a constant
SFR. We find that while both predict a systematic decline in the observed
ratios, only the time variable SFH models are capable of producing the observed
population of low mass galaxies ( < 10 Msun) with normal
Halpha-to-FUV ratios. These results demonstrate that a variable IMF alone has
difficulty explaining the observed scatter in the Halpha-to-FUV ratios. We
conclude by considering the limitations of the model SFHs, and discuss the use
of additional empirical constraints to improve future SFH modeling efforts.Comment: 15 pages, 11 Figures. Accepted for publication in Ap
O espectro das falências ovarianas ligadas ao cromossomo X
Clinically ovarian failure is presented by primary or secondary amenorrhea and high levels of pituitary gonadotropins mainly FSH. Monossomy or X-chromosome rearrangements are among a variable number of suggested etiopathogenic factors of ovarian failure in young women. Besides in Turner syndrome (X-monossomy or mosaicism), where the short stature and sexual infantilism point to the diagnosis, X-chromosome long arm (Xq) rearrangements, or genetic mutations of genes mapped at this segment are related with ovarian failure presented in prepubertal girls and in young women without other clinical signal. The present revision focuses these chromosomal abnormalities, some of them disclosed by conventional cytogenetic methods and other only disclosed by means of molecular biological toolsA falência ovariana manifesta-se clinicamente por amenorréia primária ou secundária, e do ponto de vista hormonal caracteriza-se pelos nÃveis elevados de gonadotrofinas hipofisárias, principalmente FSH, cuja etiologia pode ser atribuÃda a varias causas, como redução numérica ou rearranjos do cromossomo X, entre outras. Além da sÃndrome de Turner (monossomia do cromossomo X, com ou sem mosaicismo cromossômico), cujo principal estigma - a baixa estatura - e o infantilismo sexual apontam o diagnóstico, rearranjos do braço longo de X (Xq), ou mutações instaladas em genes mapeados neste cromossomo estão relacionados com a falência ovariana em meninas pré-púberes e em mulheres adultas jovens, sem outros sinais clÃnicos. Neste cromossomo, nos segmentos da falência ovariana precoce (FOP1 e FOP2) situam-se genes já relacionados à insuficiência ovariana de instalação precoce. Esta revisão trata destas alterações, algumas detectadas pelas técnicas citogenéticas convencionais, outras somente por meio de recursos de biologia molecularUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Disciplina de Endocrinologia e MetabologiaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de GinecologiaUNIFESP, EPM, Disciplina de Endocrinologia e MetabologiaUNIFESP, EPM, Depto. de GinecologiaSciEL
The Motions of Clusters of Galaxies and the Dipoles of the Peculiar Velocity Field
In preceding papers of this series, TF relations for galaxies in 24 clusters
with radial velocities between 1000 and 9200 km/s (SCI sample) were obtained, a
Tully-Fisher (TF) template relation was constructed and mean offsets of each
cluster with respect to the template obtained. Here, an estimate of the
line-of-sight peculiar velocities of the clusters and their associated errors
are given. It is found that cluster peculiar velocities in the Cosmic Microwave
Background reference frame do not exceed 600 k/ms and that their distribution
has a line-of-sight dispersion of 300 k/ms, suggesting a more quiescent cluster
peculiar velocity field than previously reported. When measured in a reference
frame in which the Local Group is at rest, the set of clusters at cz > 3000
km/s exhibits a dipole moment in agreement with that of the CMB, both in
amplitude and apex direction. It is estimated that the bulk flow of a sphere of
6000 km/s radius in the CMB reference frame is between 140 and 320 km/s. These
results are in agreement with those obtained from an independent sample of
field galaxies (Giovanelli et al. 1998; see astro-ph/9807274)Comment: 9 pages, 2 tables, 7 figures, uses AAS LaTex; to appear in A
Endometrial biopsy with uretral plastic No. 12 sonde
The authors demonstrate technique for obtaining endometrial fragments in 25 patients sent to Gynecological Cancer Preventive Service of the Arnaldo Vieira de Carvalho Cancer Institute, during the period of September 1991 through January 1992, presenting abnormal uterine hemorrhage. Technique consists in vacuum aspiration with the support of a No. 12 uretral sonde , provided with one lateral opening only. Correlation with curettage was positive in 88% of the patients; biopsy with sonde did not result in confirmation in three patients only. No complications at all were observed (infection, hemorrhage or uterus perforation). Authors understand that this method is in conformity with a correct diagnostic performance, being a low cost procedure, almost painless, easy to be done and furnishing sufficient material for the histopathologic diagnosis, in 88% of the cases studied.INTRODUÇÃO : Os autores demonstram a técnica de obtenção de fragmentos endometriais em 25 pacientes encaminhadas ao Serviço de Prevenção do Câncer Ginecológico do Instituto do Câncer Arnaldo Vieira de Carvalho por quadro de sangramento uterino anormal no perÃodo de setembro de 1991 a janeiro de 1992. MATERIAL E MÉTODOS: A técnica consistiu na vácuo aspiração do endométrio com auxÃlio de sonda uretral n° 12 de orifÃcio lateral único. RESULTADOS: A correlação com curetagem foi positiva em 88% dos casos; a biópsia com sonda não mostrou confirmação em apenas três pacientes. Não foram observadas complicações de qualquer espécie (infecção, hemorragia ou perfuração uterina). CONCLUSÃO: Os autores concluem que o método está adequado a uma correta abordagem diagnóstica, trata-se de procedimento de baixo custo, pouco doloroso, de fácil execução e que possibilitou material suficiente para o diagnóstico histopatológico em 88% dos casos estudadosEscola Paulista de Medicina Instituto de Câncer Antonio Vieira de Carvalho Gynecological Oncology DepartmentUNIFESP, EPM, Instituto de Câncer Antonio Vieira de Carvalho Gynecological Oncology DepartmentSciEL
The ACS Nearby Galaxy Survey Treasury. X. Quantifying the Star Cluster Formation Efficiency of Nearby Dwarf Galaxies
We study the relationship between the field star formation and cluster
formation properties in a large sample of nearby dwarf galaxies. We use optical
data from the Hubble Space Telescope and from ground-based telescopes to derive
the ages and masses of the young (t_age < 100Myr) cluster sample. Our data
provides the first constraints on two proposed relationships between the star
formation rate of galaxies and the properties of their cluster systems in the
low star formation rate regime. The data show broad agreement with these
relationships, but significant galaxy-to-galaxy scatter exists. In part, this
scatter can be accounted for by simulating the small number of clusters
detected from stochastically sampling the cluster mass function. However, this
stochasticity does not fully account for the observed scatter in our data
suggesting there may be true variations in the fraction of stars formed in
clusters in dwarf galaxies. Comparison of the cluster formation and the
brightest cluster in our sample galaxies also provide constraints on cluster
destruction models.Comment: 16 pages, 9 figures, Accepted to Ap
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