535 research outputs found
NICMOS Snapshot Survey of Damped Lyman Alpha Quasars
We image 19 quasars with 22 damped Lyman alpha (DLA) systems using the F160W
filter and the Near-Infrared Camera and Multiobject Spectrograph aboard the
Hubble Space Telescope, in both direct and coronagraphic modes. We reach 5
sigma detection limits of ~H=22 in the majority of our images. We compare our
observations to the observed Lyman-break population of high-redshift galaxies,
as well as Bruzual & Charlot evolutionary models of present-day galaxies
redshifted to the distances of the absorption systems. We predict H magnitudes
for our DLAs, assuming they are producing stars like an L* Lyman-break galaxy
(LBG) at their redshift. Comparing these predictions to our sensitivity, we
find that we should be able to detect a galaxy around 0.5-1.0 L* (LBG) for most
of our observations. We find only one new possible candidate, that near
LBQS0010-0012. This scarcity of candidates leads us to the conclusion that most
DLA systems are not drawn from a normal LBG luminosity function nor a local
galaxy luminosity function placed at these high redshifts.Comment: 31 pages, 8 figures, Accepted for Feb. 10 issue of Ap
The Morphological Content of Ten EDisCS Clusters at 0.5 < z < 0.8
We describe Hubble Space Telescope (HST) imaging of 10 of the 20 ESO Distant
Cluster Survey (EDisCS) fields. Each ~40 square arcminute field was imaged in
the F814W filter with the Advanced Camera for Surveys Wide Field Camera. Based
on these data, we present visual morphological classifications for the ~920
sources per field that are brighter than I_auto=23 mag. We use these
classifications to quantify the morphological content of 10
intermediate-redshift (0.5 < z < 0.8) galaxy clusters within the HST survey
region. The EDisCS results, combined with previously published data from seven
higher redshift clusters, show no statistically significant evidence for
evolution in the mean fractions of elliptical, S0, and late-type (Sp+Irr)
galaxies in clusters over the redshift range 0.5 < z < 1.2. In contrast,
existing studies of lower redshift clusters have revealed a factor of ~2
increase in the typical S0 fraction between z=0.4 and z=0, accompanied by a
commensurate decrease in the Sp+Irr fraction and no evolution in the elliptical
fraction. The EDisCS clusters demonstrate that cluster morphological fractions
plateau beyond z ~ 0.4. They also exhibit a mild correlation between
morphological content and cluster velocity dispersion, highlighting the
importance of careful sample selection in evaluating evolution. We discuss
these findings in the context of a recently proposed scenario in which the
fractions of passive (E,S0) and star-forming (Sp,Irr) galaxies are determined
primarily by the growth history of clusters.Comment: 18 pages, 7 figures; To be published in ApJ; minor changes made to
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Description of hospital pharmacy management practice
Health institutions, particularly hospitals, are characterized as complex structures that need managers with a global view of the institution and its relations with the external environment. The hospital pharmacy is a strategic unit, which cooperates with the institutional management and integrates the multiprofessional team in the process related to the acquisition, provision and control of essential inputs for the inpatient care process. The objective in this study is to demonstrate the applicability, in the context of hospital-based health, of a performance measuring system at the pharmacy. Method: A descriptive and longitudinal study was undertaken on the evolution of the key indicator Absence Rate of Standardized Drugs in inpatient care between March 2004 and December 2013. This indicator was employed to monitor the impact of changes the Pharmacy Division has been implementing, as the first step of the pharmaceutical care cycle in the model of the process-based managed approach at a public university hospital. Qualitative data collection methods were used, including observation and documentary analysis, as well as quantitative data collection. Results: After the application of the model, one point of change in the key performance indicator was detected in the tenth month, when the process-based management model was implemented at the pharmacy. Conclusions: The process-based management approach was effective for the hospital pharmacy. The premise adopted is that the administrative changes (interferences), focused on the improvement of the processes and the selection and monitoring of indicators, influence the processes, reducing the variability and improving the qualityAs instituições de saúde, especialmente hospitais, são caracterizadas como estruturas complexas que precisam de administradores com uma visão global da instituição e de suas relações com o ambiente externo. A farmácia hospitalar é uma unidade estratégica, que colabora com a administração institucional e integra a equipe multiprofissional no processo que tange a aquisição, provisão e controle de insumos essenciais para o processo do atendimento do paciente internado. Este estudo tem como objetivo demonstrar a aplicabilidade, no contexto da saúde hospitalar, de um sistema de medição de desempenho da farmácia. Método: Trata-se de um estudo descritivo, longitudinal, sobre a evolução do indicador chave Taxa de Falta de Medicamentos Padronizados na assistência do paciente internado, no período de março de 2004 a dezembro de 2013. Esse indicador foi empregado para monitoramento do impacto de mudanças que a Divisão de Farmácia vem implementando, como primeira etapa do ciclo de assistência farmacêutica dentro do modelo da abordagem de gestão por processos, em um hospital público universitário. Foram usados métodos de coleta de dados qualitativos, incluindo a observação e análise documental, bem como coleta de dados quantitativos. Resultados: Após a aplicação do modelo, um ponto de mudança no indicador chave de desempenho, foi detectado no 10º mês, quando o modelo de gestão baseado em processo foi implementado na farmácia. Conclusões: A abordagem de gestão baseada em processos foi eficaz para a farmácia hospitalar. A premissa adotada é que as mudanças administrativas (interferências), com foco na melhoria dos processos e seleção e acompanhamento de indicadores, têm influencia sobre os processos, reduzindo a variabilidade e melhoria da qualidad
Plastic Flow in Two-Dimensional Solids
A time-dependent Ginzburg-Landau model of plastic deformation in
two-dimensional solids is presented. The fundamental dynamic variables are the
displacement field \bi u and the lattice velocity {\bi v}=\p {\bi u}/\p t.
Damping is assumed to arise from the shear viscosity in the momentum equation.
The elastic energy density is a periodic function of the shear and tetragonal
strains, which enables formation of slips at large strains. In this work we
neglect defects such as vacancies, interstitials, or grain boundaries. The
simplest slip consists of two edge dislocations with opposite Burgers vectors.
The formation energy of a slip is minimized if its orientation is parallel or
perpendicular to the flow in simple shear deformation and if it makes angles of
with respect to the stretched direction in uniaxial stretching.
High-density dislocations produced in plastic flow do not disappear even if
the flow is stopped. Thus large applied strains give rise to metastable,
structurally disordered states. We divide the elastic energy into an elastic
part due to affine deformation and a defect part. The latter represents degree
of disorder and is nearly constant in plastic flow under cyclic straining.Comment: 16pages, Figures can be obtained at
http://stat.scphys.kyoto-u.ac.jp/index-e.htm
Primerjava toksičnosti etanola in acetaldehida za podganje astrocite v primarni kulturi
This study compared the effects of toxicity of ethanol and its first metabolite acetaldehyde in rat astrocytes through cell viability and cell proliferation. The cells were treated with different concentrations of ethanol in the presence or absence of a catalase inhibitor 2-amino-1,2,4 triazole (AMT) or with different concentrations of acetaldehyde. Cell viability was assessed using the trypan blue test. Cell proliferation was assessed after 24 hours and after seven days of exposure to either ethanol or acetaldehyde.
We showed that both ethanol and acetaldehyde decreased cell viability in a dose-dependent manner. In proliferation studies, after seven days of exposure to either ethanol or acetaldehyde, we observed a significant dose-dependent decrease in cell number. The protein content study showed biphasic dose-response curves, after 24 hours and seven days of exposure to either ethanol or acetaldehyde. Co-incubation in the presence of AMT significantly reduced the inhibitory effect of ethanol on cell proliferation.
We concluded that long-term exposure of astrocytes to ethanol is more toxic than acute exposure. Acetaldehyde is a much more potent toxin than ethanol, and at least a part of ethanol toxicity is due to ethanol’s first metabolite acetaldehyde.V študiji smo primerjali toksičnost etanola in njegovega prvega metabolita acetaldehida za podganje astrocite z določitvijo celične viabilnosti in proliferacije. Celične kulture smo tretirali z različnimi
koncentracijami etanola, etanola v prisotnosti inhibitorja katalaze 2-amino-1,2,4 triazol-a (AMT) ali z različnimi koncentracijami acetaldehida. Celično viabilnost smo vrednotili s pomočjo testa s tripanskim modrilom, celično proliferacijo pa s štetjem celic in določitvijo koncentracije proteinov po 24-urni, kot
tudi 7-dnevni izpostavljenosti.
S študijo smo pokazali, da tako etanol kot tudi acetaldehid v odvisnosti od njune koncentracije zmanjšata celično viabilnost. V študiji proliferacije sta etanol in acetaldehid, v odvisnosti od njunih koncentracij, značilno zmanjšala število celic po 7-dnevni izpostavljenosti. Pri ugotavljanju vsebnosti proteinov smo
dobili bifazno krivuljo tako po 24-urni, kot tudi po 7-dnevni izpostavljenosti različnim koncentracijam etanola oziroma acetaldehida. Prisotnost AMT je signifi kantno zmanjšala učinek etanola na celično proliferacijo.
Zaključimo lahko, da je dolgotrajna izpostavljenost astrocitov etanolu bolj toksična kot akutna. Acetaldehid je močnejši toksin kot etanol in vsaj del toksičnosti etanola je posledica delovanja njegovega prvega
metabolita, acetaldehida
The Color-Magnitude Effect in Early-Type Cluster Galaxies
We present the analysis of the color-magnitude relation (CMR) for a sample of
57 X-ray detected Abell clusters within the redshift interval 0.02 <= z <=
0.18. We use the B-R vs R color-magnitude plane to establish that the CMR is
present in all our low-redshift clusters and can be parameterized by a single
straight line.We find that the CMRs for this large cluster sample of different
richness and cluster types are consistent with having universal properties. The
k-corrected color of the individual CMRs in the sample at a fixed absolute
magnitude have a small intrinsic dispersion of ~0.05 mag. The slope of the CMR
is consistent with being the same for all clusters, with the variations
entirely accountable by filter band shifting effects. We determine the mean of
the dispersion of the 57 CMRs to be 0.074 mag, with a small rms scatter of
0.026 mag. However, a modest amount of the dispersion arises from photometric
measurement errors and possible background cluster superpositions; and the
derived mean dispersion is an upper limit. Models which explain the CMR in
terms of metallicity and passive evolution can naturally reproduce the observed
behavior of the CMR in this paper. The observed properties of the CMR are
consistent with models in which the last episode of significant star formation
in cluster early-type galaxies occurred significantly more than ~3 Gyr ago, and
that the core set of early-type galaxies in clusters were formed more than 7
Gyr ago. (abridged)Comment: Accepted ApJ, 17 pages, 4 figures (high-res fig 1 available in ApJ
version
Determinants of bed net use in children under five and household bed net ownership on Bioko Island, Equatorial Guinea
BACKGROUND: As part of comprehensive malaria control strategies, the Bioko Island Malaria Control Project (BIMCP) distributed 110,000 long-lasting insecticide-treated nets (LLIN) in late 2007 with the aim of providing one net for each sleeping area. Despite attaining initially very high levels of net coverage and net use, many children under five years of age did not sleep under a net by 2009, according to annual malaria indicator surveys. The aim of this study was to assess the determinants of bed net use in children under five and bed net ownership of the households in which they live. METHODS: Using data from annual cross-sectional household surveys of 2008 and 2009, we investigated factors associated with sleeping under a mosquito net the night prior to the survey, and a households owning at least one net, in all households which had at least one child under five years. Amongst others, caregiver's knowledge of malaria and household characteristics including a socio-economic score (SES), based on ownership of household assets, were analysed for their effect on net ownership and use. RESULTS: There was a decline of around 32% in the proportion of households that owned at least one net between 2008 and 2009. Higher household bed net ownership was associated with knowing how malaria was prevented and transmitted, having the house sprayed in the previous 12 months, having fewer children under five in the household, and children being sick at some point in the previous 14 days. Higher bed net use in children < 5 was associated with being sick at some point in the last 14 days prior to the survey, living in an urban area, more years of education of the head of the household, household ownership of at least one ITN (as opposed to an untreated net) and the year in which the survey took place. CONCLUSIONS: The big fall in bed net use from 2008 to 2009 was attributable to the striking decline in ownership. Although ownership was similar in rural and urban areas, rural households were less likely to protect their children with bed nets. Knowledge about malaria was an important determinant of bed net ownership. Further research is needed to elucidate the decline in bed net ownership between 2008 and 2009
An mRNA decapping mutant deficient in P body assembly limits mRNA stabilization in response to osmotic stress
Yeast is exposed to changing environmental conditions and must adapt its genetic program to provide a homeostatic intracellular environment. An important stress for yeast in the wild is high osmolarity. A key response to this stress is increased mRNA stability primarily by the inhibition of deadenylation. We previously demonstrated that mutations in decapping activators (edc3∆ lsm4∆C), which result in defects in P body assembly, can destabilize mRNA under unstressed conditions. We wished to examine whether mRNA would be destabilized in the edc3∆ lsm4∆C mutant as compared to the wild-type in response to osmotic stress, when P bodies are intense and numerous. Our results show that the edc3∆ lsm4∆C mutant limits the mRNA stability in response to osmotic stress, while the magnitude of stabilization was similar as compared to the wild-type. The reduced mRNA stability in the edc3∆ lsm4∆C mutant was correlated with a shorter PGK1 poly(A) tail. Similarly, the MFA2 mRNA was more rapidly deadenylated as well as significantly stabilized in the ccr4∆ deadenylation mutant in the edc3∆ lsm4∆C background. These results suggest a role for these decapping factors in stabilizing mRNA and may implicate P bodies as sites of reduced mRNA degradation
From the production of rules to seed production: Global Intellectual Property and local knowledge
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