326 research outputs found
X-ray and -ray Studies of the Millisecond Pulsar and Possible X-ray Binary/Radio Pulsar Transition Object PSR J1723-2837
We present X-ray observations of the "redback" eclipsing radio millisecond
pulsar and candidate radio pulsar/X-ray binary transition object PSR
J1723-2837. The X-ray emission from the system is predominantly non-thermal and
exhibits pronounced variability as a function of orbital phase, with a factor
of ~2 reduction in brightness around superior conjunction. Such temporal
behavior appears to be a defining characteristic of this variety of peculiar
millisecond pulsar binaries and is likely caused by a partial geometric
occultation by the main-sequence-like companion of a shock within the binary.
There is no indication of diffuse X-ray emission from a bow shock or pulsar
wind nebula associated with the pulsar. We also report on a search for point
source emission and -ray pulsations in Fermi Large Area Telescope data
using a likelihood analysis and photon probability weighting. Although PSR
J1723-2837 is consistent with being a -ray point source, due to the
strong Galactic diffuse emission at its position a definitive association
cannot be established. No statistically significant pulsations or modulation at
the orbital period are detected. For a presumed source detection, the implied
-ray luminosity is 5% of its spin-down power. This indicates
that PSR J1723-2837 is either one of the least efficient -ray producing
millisecond pulsars or, if the detection is spurious, the -ray emission
pattern is not directed towards us.Comment: 10 pages, 6 figures; accepted for publication in the Astrophysical
Journa
Graduate competencies and employability: the impact of matching firmsâ needs and personal attainments
[Abstract]:Professional competencies are a key factor in gauging how employable a graduate is.
This paper demonstrates that individuals who have best developed the competencies
which firms feel to be most important are more likely to be in a position to obtain a job.
To this end, we have developed an indicator that measures the proximity between the
relative levels of both importance and attainments. Results confirm the feeling among
experts that the most relevant competencies in the labour market are predominantly of
the systemic type, i.e. transferable personal competencies, to the detriment of more
instrumental competencies related to capacities and graduate education. This paper
clearly points to the fact that universities must change their traditional focus and make a
special effort to help their students to develop those competencies that best foster
employabilit
Phylogeography of Rift Valley Fever Virus in Africa Reveals Multiple Introductions in Senegal and Mauritania
Rift Valley Fever (RVF) virus (Family Bunyaviridae) is an arthropod-borne RNA virus that infects primarily domestic ruminants and occasionally humans. RVF epizootics are characterized by numerous abortions and mortality among young animals. In humans, the illness is usually characterized by a mild self-limited febrile illness, which could progress to more serious complications. RVF virus is widespread and endemic in many regions of Africa. In Western Africa, several outbreaks have been reported since 1987 when the first major one occurred at the frontier of Senegal and Mauritania. Aiming to evaluate the spreading and molecular epidemiology in these countries, RVFV isolates from 1944 to 2008 obtained from 18 localities in Senegal and Mauritania and 15 other countries were investigated. Our results suggest that a more intense viral activity possibly took place during the last century compared to the recent past and that at least 5 introductions of RVFV took place in Senegal and Mauritania from distant African regions. Moreover, Barkedji in Senegal was possibly a hub associated with the three distinct entries of RVFV in West Africa
Epoetin Alfa Improves Anemia and Anemia-Related, Patient-Reported Outcomes in Patients with Breast Cancer Receiving Myelotoxic Chemotherapy: Results of a European, Multicenter, Randomized, Controlled Trial
This study evaluated the effects of epoetin alfa on patient-reported outcomes in patients with breast cancer receiving myelotoxic chemotherapy. Early intervention with epoetin alfa was well tolerated and improved anemia-related patient-reported outcomes
Modularity and evolutionary constraints in a baculovirus gene regulatory network
Abstract\ud
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Background\ud
The structure of regulatory networks remains an open question in our understanding of complex biological systems. Interactions during complete viral life cycles present unique opportunities to understand how host-parasite network take shape and behave. The Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) is a large double-stranded DNA virus, whose genome may encode for 152 open reading frames (ORFs). Here we present the analysis of the ordered cascade of the AgMNPV gene expression.\ud
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Results\ud
We observed an earlier onset of the expression than previously reported for other baculoviruses, especially for genes involved in DNA replication. Most ORFs were expressed at higher levels in a more permissive host cell line. Genes with more than one copy in the genome had distinct expression profiles, which could indicate the acquisition of new functionalities. The transcription gene regulatory network (GRN) for 149 ORFs had a modular topology comprising five communities of highly interconnected nodes that separated key genes that are functionally related on different communities, possibly maximizing redundancy and GRN robustness by compartmentalization of important functions. Core conserved functions showed expression synchronicity, distinct GRN features and significantly less genetic diversity, consistent with evolutionary constraints imposed in key elements of biological systems. This reduced genetic diversity also had a positive correlation with the importance of the gene in our estimated GRN, supporting a relationship between phylogenetic data of baculovirus genes and network features inferred from expression data. We also observed that gene arrangement in overlapping transcripts was conserved among related baculoviruses, suggesting a principle of genome organization.\ud
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Conclusions\ud
Albeit with a reduced number of nodes (149), the AgMNPV GRN had a topology and key characteristics similar to those observed in complex cellular organisms, which indicates that modularity may be a general feature of biological gene regulatory networks.JVCO, CTB and AI hold FAPESP scholarships (04/12456-0, 09/16740-8 and 12/04818-5), AFB and CCMF hold CAPES-MSc and PhD scholarships and PMAZ holds a CNPq-PQ scholarship. This work was supported financially by FAPESP (Fundação de Amparo a Pesquisa do Estado de São Paulo, process: 2007/55282-0)
CAPACIDADE FUNCIONAL E QUALIDADE DE VIDA DE IDOSAS USUĂRIAS DAS ACADEMIAS DA TERCEIRA IDADE E NĂO PRATICANTES DE EXERCĂCIO FĂSICO
O objetivo desse presente estudo foi de analisar a capacidade funcional e qualidade de vida de mulheres idosas que praticavam exercĂcios nas Academias da terceira idade (ATI) e idosas nĂŁo praticantes de nenhum tipo de exercĂcio e analisar a correlação dos parĂąmetros da capacidade funcional e qualidade de vida desses sujeitos. Trata-se de um estudo transversal, realizado com 80 idosas. A amostra foi dividida em grupo nĂŁo praticante de exercĂcio fĂsico (G1) e usurĂĄrio da ATI (G2). Foi utilizado um questionĂĄrio sociodemogrĂĄfico e de saĂșde, o WHOQOL-BREF e o WHOQOL-OLD. A capacidade funcional foi avaliada por meio dos testes do Protocolo de Avaliação Funcional do Grupo de Desenvolvimento Latino-Americano para Maturidade (GDLAM). A anĂĄlise dos dados foi feita por meio dos testes Kolmogorov-Smirnov, Qui-quadrado de Pearson (X2) e correlação de Spearman. Considerou-se um nĂvel de significĂąncia de p<0,05. As idosas do G2 apresentaram maior escore na faceta de qualidade de vida de Participação Social (p = 0,004). As idosas do G2 realizaram o teste de Levantar da cadeira e mover-se pela casa em menor tempo (p=0,001), enquanto as idosas do G1 fizeram em menor tempo o teste de vestir e tirar a camiseta (p=0,001). Os melhores escores obtidos no item levantar-se da cadeira e mover-se pela casa, indicam importantes contribuiçÔes possĂveis das ATI para a dimensĂŁo fĂsica das condiçÔes de saĂșde dos idosos, alĂ©m do benefĂcio na socialização verificada a percepção da qualidade de vida dessa população
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