328 research outputs found
A radio study of the superwind galaxy NGC1482
We present multifrequency radio continuum as well as HI observations of the
superwind galaxy NGC1482, with both the GMRT and the VLA. This galaxy has a
remarkable hourglass-shaped optical emission line outflow as well as bi-polar
soft X-ray bubbles on opposite sides of the galactic disk. The low-frequency,
lower-resolution radio observations show a smooth structure. From the
non-thermal emission, we estimate the available energy in supernovae, and
examine whether this would be adequate to drive the observed superwind outflow.
The high-frequency, high-resolution radio images of the central starburst
region located at the base of the superwind bi-cone shows one prominent peak
and more extended emission with substructure. This image has been compared with
the infrared, optical red-continuum, H_alpha, and, soft and hard X-ray images
from Chandra. The peak of infrared emission is the only feature which is
coincident with the prominent radio peak, and possibly defines the centre of
the galaxy. The HI observations with the GMRT show two blobs of emission on
opposite sides of the central region. These are rotating about the centre of
the galaxy and are located at ~2.4 kpc from it. In addition, these observations
also reveal a multicomponent HI-absorption profile against the central region
of the radio source, with a total width of ~250 km/s. The extreme blue- and
red-shifted absorption components are at 1688 and 1942 km/s respectively, while
the peak absorption is at 1836 km/s. This is consistent with the heliocentric
systemic velocity of 1850+/-20 km/s, estimated from a variety of observations.
We discuss possible implications of these results.Comment: 11 pages, 10 figures, 4 tables, accepted for publication in MNRA
Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation
High-redshift Lyman-alpha blobs are extended, luminous, but rare structures
that appear to be associated with the highest peaks in the matter density of
the Universe. Their energy output and morphology are similar to powerful radio
galaxies, but the source of the luminosity is unclear. Some blobs are
associated with ultraviolet or infrared bright galaxies, suggesting an extreme
starburst event or accretion onto a central black hole. Another possibility is
gas that is shock excited by supernovae. However some blobs are not associated
with galaxies, and may instead be heated by gas falling into a dark matter
halo. The polarization of the Ly-alpha emission can in principle distinguish
between these options, but a previous attempt to detect this signature returned
a null detection. Here we report on the detection of polarized Ly-alpha from
the blob LAB1. Although the central region shows no measurable polarization,
the polarized fraction (P) increases to ~20 per cent at a radius of 45 kpc,
forming an almost complete polarized ring. The detection of polarized radiation
is inconsistent with the in situ production of Ly-alpha photons, and we
conclude that they must have been produced in the galaxies hosted within the
nebula, and re-scattered by neutral hydrogen.Comment: Published in the August 18 issue of Nature. 1750 words, 3 figures,
and full Supplementary Information. Version has not undergone proofing.
Reduced and processed data products are available here:
http://obswww.unige.ch/people/matthew.hayes/LymanAlpha/LabPol
Investigating how the attributes of live theatre productions influence consumption choices using conjoint analysis : the example of the National Arts Festival, South Africa
While there is a fair amount of work on determinants of demand for the live performing arts, results have often been contradictory with little explanatory power. This may be because of the difficulty in describing the attributes of a performance, particularly in terms of its quality, and the heterogeneity of consumer preferences. This article uses conjoint analysis, also called choice experiments, to investigate the impact of the attributes of live theatre performances on demand, using data collected from 483 randomly chosen attenders at live theatre performances at the 2008 South African National Arts Festival. Attributes include the type of cast (professional, semi-professional or amateur), reputation of the producer/director, the context or setting, production type and ticket price of the show. Results largely support the a priori expectations based on the results of other demand studies. For example, it is found that the age of consumers affects the type of show chosen, that utility and willingness to pay increase for shows with professional and semi-professional casts and that 93% of the potential audience prefer shows with a South African context. It is concluded that the method could prove useful to both event organisers and policy makers, especially where the goal is to broaden access to the arts
Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat
In this study we examined the effects of exposure to the antiandrogenic fungicide vinclozolin (Vz) on the development of two sex-differentiated behaviors that are organized by the perinatal actions of androgens. Pregnant Long-Evans rats were administered a daily oral dose of 0, 1.5, 3, 6, or 12 mg/kg Vz from the 14th day of gestation through postnatal day (PND)3. The social play behavior of juvenile offspring was examined on PND22 and again on PND34 during play sessions with a same-sex littermate. After they reached adulthood, the male offspring were examined with the ex copula penile reflex procedure to assess erectile function. Vz did not produce any gross maternal or neonatal toxicity, nor did it reduce the anogenital distance in male pups. We observed no effects of Vz on play behavior on PND22. However, the 12-mg/kg Vz dose significantly increased play behavior in the male offspring on PND34 compared with controls. The most dramatic increases were seen with the nape contact and pounce behavior components of play. The Vz effect was more pronounced in male than in female offspring. As adults, male offspring showed a significant reduction of erections at all dose levels during the ex copula penile reflex tests. The 12-mg/kg dose was also associated with an increase in seminal emissions. These effects demonstrate that perinatal Vz disrupts the development of androgen-mediated behavioral functions at exposure levels that do not produce obvious structural changes or weight reductions in androgen-sensitive reproductive organs
Wide-Field Imaging and Polarimetry for the Biggest and Brightest in the 20GHz Southern Sky
We present wide-field imaging and polarimetry at 20GHz of seven of the most
extended, bright (Stot >= 0.50 Jy), high-frequency selected radio sources in
the southern sky with declinations < -30 deg. Accompanying the data are brief
reviews of the literature for each source, The results presented here aid in
the statistical completeness of the Australia Telescope 20GHz Survey's bright
source sample. The data are of crucial interest for future cosmic microwave
background missions as a collection of information about candidate calibrator
sources. We are able to obtain data for seven of the nine sources identified by
our selection criteria. We report that Pictor A is thus far the best
extragalactic calibrator candidate for the Low Frequency Instrument of the
Planck European Space Agency mission due to its high level of integrated
polarized flux density (0.50+/-0.06 Jy) on a scale of 10 arcmin. Six of the
seven sources have a clearly detected compact radio core, with either a null or
less than two percent detection of polarized emission from the nucleus. Most
sources with detected jets have magnetic field alignments running in a
longitudinal configuration, however PKS1333-33 exhibits transverse fields and
an orthogonal change in field geometry from nucleus to jets.Comment: 17 pages, 9 figures, 2 table
Coleta de dados e manejo dos pacientes hipertensos
Introdução: A pesquisa realizada teve como objetivo a análise e a educação e manejo dos pacientes hipertensos na unidade básica de saúde Jardim Laguna em prol de orientar e alertar sobre os malefÃcios de uma pressão descontrolada e uma alimentação desbalanceada, e como a famÃlia pode ajudar nesses momentos, Materiais e métodos: Foi realizado um ensaio clÃnico não controlado, quantificativo, onde foi aplicado aos pacientes um questionário, produzido pelo próprio autor, com perguntas relacionadas a saúde e o bem estar do paciente, onde foram aplicadas no primeiro contato com o paciente e acompanhados durante 01 mês. Os pacientes submetidos a esse estudo foram pacientes com mais de 20 anos já hipertensos, acompanhados de familiares para a conversa sobre como adequar o tratamento. Resultados: os participantes da pesquisa obtiveram melhor conhecimento em relação aos malefÃcios da HAS e sobre os benefÃcios do exercÃcio fÃsico à saúde. Todos relataram que acharam benéficos a intervenção e que irão levar para a vida o conhecimento apreendido. Conclusão: A unidade básica de saúde achou produtiva a intervenção, e tem o desejo de continuar a intervenção sem os alunos, já que com ela é possÃvel quantificar e analisar melhor os dados da região, para uma análise epidemiológica, o que não é possÃvel atualmente já que a prefeitura de contagem não tem disponÃvel
Leadership Competencies for Digital Transformation : Evidence from Multiple Cases
Digital transformation (DT) is disrupting industrial organizations, which require significant changes in their properties to remain competitive. This calls for strong leadership to drive this transformation. However, what leadership competencies are required to lead DT impactfully is unclear. Therefore, we seek to identify the key leadership competencies by employing a qualitative, grounded theory approach. By conducting interviews of ten DT experts from two hardcore industrial organizations, we highlight five key leadership competencies that industrial organizations need to develop in their leaders: digital vision, digital knowledge, failing fast, empowerment, and managing diverse teams. The results of this study will help industrial organizations to strategically prepare their leadership for the requirements of DT.©2020 Springer. This is a post-peer-review, pre-copyedit version of an article published in Advances in Human Factors, Business Management and Leadership: Proceedings of the AHFE 2020 Virtual Conferences on Human Factors, Business Management and Society, and Human Factors in Management and Leadership, July 16-20, 2020, USA. The final authenticated version is available online at: http://dx.doi.org/0.1007/978-3-030-50791-6_11.fi=vertaisarvioitu|en=peerReviewed
Neurological, Psychiatric, and Biochemical Aspects of Thiamine Deficiency in Children and Adults.
Thiamine (vitamin B1) is an essential nutrient that serves as a cofactor for a number of enzymes, mostly with mitochondrial localization. Some thiamine-dependent enzymes are involved in energy metabolism and biosynthesis of nucleic acids whereas others are part of the antioxidant machinery. The brain is highly vulnerable to thiamine deficiency due to its heavy reliance on mitochondrial ATP production. This is more evident during rapid growth (i.e., perinatal periods and children) in which thiamine deficiency is commonly associated with either malnutrition or genetic defects. Thiamine deficiency contributes to a number of conditions spanning from mild neurological and psychiatric symptoms (confusion, reduced memory, and sleep disturbances) to severe encephalopathy, ataxia, congestive heart failure, muscle atrophy, and even death. This review discusses the current knowledge on thiamine deficiency and associated morbidity of neurological and psychiatric disorders, with special emphasis on the pediatric population, as well as the putative beneficial effect of thiamine supplementation in autism spectrum disorder (ASD) and other neurological conditions
Errors in the measurement of voltage-activated ion channels in cell-attached patch-clamp recordings
Patch-clamp recording techniques have revolutionized understanding of the function and sub-cellular location of ion channels in excitable cells. The cell-attached patch-clamp configuration represents the method of choice to describe the endogenous properties of voltage-activated ion channels in the axonal, somatic and dendritic membrane of neurons, without disturbance of the intracellular milieu. Here, we directly examine the errors associated with cell-attached patch-clamp measurement of ensemble ion channel activity. We find for a number of classes of voltage-activated channels, recorded from the soma and dendrites of neurons in acute brain-slices and isolated cells, that the amplitude and kinetics of ensemble ion channel activity recorded in cell-attached patches is significantly distorted by transmembrane voltage changes generated by the flow of current through the activated ion channels. We outline simple error–correction procedures that allow a more accurate description of the density and properties of voltage-activated channels to be incorporated into computational models of neurons
Physical activity and risk of colon adenoma: A meta-analysis
BACKGROUND: Little evidence is available on the relation of physical activity with colon adenomas, a colon cancer precursor. METHODS: We conducted a systematic literature review and meta-analysis of published studies (in English) through April 2010, examining physical activity or exercise and risk or prevalence of colon adenoma or polyp. Random effects models were used to estimate relative risks (RRs) and corresponding confidence intervals (CIs). A total of 20 studies were identified that examined the association and provided RRs and corresponding 95% CIs. RESULTS: A significant inverse association between physical activity and colon adenomas was found with an overall RR of 0.84 (CI: 0.77–0.92). The association was similar in men (RR=0.81, CI: 0.67–0.98) and women (RR=0.87, CI: 0.74–1.02). The association appeared slightly stronger in large/advanced polyps (RR=0.70, CI: 0.56–0.88). CONCLUSION: This study confirms previous reports of a significant inverse association of physical activity and colon adenoma, and suggests that physical activity can have an important role in colon cancer prevention
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