760 research outputs found
Ionized Gas Motions and the Structure of Feedback Near a Forming Globular Cluster in NGC 5253
We observed Brackett 4.05m emission towards the supernebula in
NGC 5253 with NIRSPEC on Keck II in adaptive optics mode, NIRSPAO, to probe
feedback from its exciting embedded super star cluster (SSC). NIRSPEC's
Slit-Viewing Camera was simultaneously used to image the K-band continuum at
resolution. We register the IR continuum with HST imaging, and
find that the visible clusters are offset from the K-band peak, which coincides
with the Br peak of the supernebula and its associated molecular
cloud. The spectra of the supernebula exhibit Br emission with a
strong, narrow core. The linewidths are 65-76 km s, FWHM, comparable to
those around individual ultra-compact HII regions within our Galaxy. A weak,
broad (FWHM150-175 km s) component is detected on the base of
the line, which could trace a population of sources with high-velocity winds.
The core velocity of Br emission shifts by +13 km s from NE to
SW across the supernebula, possibly indicating a bipolar outflow from an
embedded object, or linked to a foreground redshifted gas filament. The results
can be explained if the supernebula comprises thousands of ionized wind regions
around individual massive stars, stalled in their expansion due to critical
radiative cooling and unable to merge to drive a coherent cluster wind. Based
on the absence of an outflow with large mass loss, we conclude that feedback is
currently ineffective at dispersing gas, and the SSC retains enriched material
out of which it may continue to form stars.Comment: 24 pages, 9 figure
A Content Analysis of Documentation of Nature Play in Early Childhood Teacher Education Programs in Australia
This study theoretically aligns with research that purports that nature play positively contributes to sustainability stewardship. Early childhood teachers can plan for and nurture childrenās capabilities and dispositions for sustainability stewardship. Initial teacher education programs contribute to the professional learning of preservice early childhood teachersā perceptions regarding nature play. This article details the findings of content analysis to explore and uncover the existence of nature play in online, publicly available documents representing twenty-two early childhood teacher qualifications. In what ways is nature play evidenced in early childhood initial teacher education programs in Australia? The findings highlight potential discrepancies between the values related to nature play in the early childhood field and the content in initial teacher education programming. The article concludes with implications for teacher education programs and proposed recommendations for ongoing research
Sleep and breast and prostate cancer risk in the MCC-Spain study
Breast and prostate cancers have been associated with circadian disruption. Some previous studies
examined associations of sleep duration and breast or prostate cancer risk though findings remain
inconsistent. This study examines associations of a range of detailed sleep characteristics and breast
and prostate cancer risk in a large-scale population-based caseācontrol study, MCC-Spain. A total
of 1738 incident breast cancer cases, 1112 prostate cancer cases and frequency matched controls
(n = 1910, and 1493 respectively) were recruited. Detailed data on habitual sleep duration, quality,
timing, and daytime napping (āsiestaā) were collected at recruitment. Additional data on sleep habits
during both the previous year and at age 40 years were also subsequently captured. Adjusted odds
ratios (ORs) and 95% confidence intervals (CI) were estimated. There were no associations of habitual
sleep duration (h), timing of sleep, or any or specific sleep problems, and either breast and prostate
cancer risk. There was a significant positive association of ever taking habitual siestas at recruitment
and breast cancer risk (OR = 1.22, 95% CI 1.06ā1.42), which strengthened with increased frequency
or duration. There were also significant positive associations observed for both breast and prostate
cancer, among those reporting recent sleep problems, but not sleep problems at age 40 years, in a
subsequent circadian questionnaire. Adverse associations with siesta and disturbed sleep during the
previous year likely reflect symptoms of developing/diagnosed cancer and comorbidities. Overall,
there was no clear association between various sleep characteristics and breast or prostate cancer risk
observed
Association of occupational heat exposure and colorectal cancer in the MCC-Spain study
Objective Heat exposure and heat stress/strain is a concern for many workers. There is increasing interest in
potential chronic health effects of occupational heat exposure, including cancer risk. We examined potential
associations of occupational heat exposure and colorectal cancer (CRC) risk in a large Spanish multi-caseācontrol
study.
Methods We analyzed data on 1198 histologically confirmed CRC cases and 2690 frequency-matched controls.
The Spanish job-exposure matrix, MatEmEsp, was used to assign heat exposure estimates to the lifetime occupations
of participants. Three exposure indices were assessed: ever versus never exposed, cumulative exposure and
duration (years). We estimated odds ratios (OR) and 95% confidence intervals (CI) using unconditional logistic
regression adjusting for potential confounders.
Results Overall, there was no association of ever, compared with never, occupational heat exposure and CRC
(OR 1.09, 95% CI 0.92ā1.29). There were also no associations observed according to categories of cumulative
exposure or duration, and there was no evidence for a trend. There was no clear association of ever occupational
heat exposure and CRC in analysis conducted among either men or women when analyzed separately. Positive
associations were observed among women in the highest categories of cumulative exposure (OR 1.81, 95% CI
1.09ā3.03) and duration (OR 2.89, 95% CI 1.50ā5.59) as well as some evidence for a trend (P<0.05).
Conclusion Overall, this study provides no clear evidence for an association between occupational heat exposure
and CRC.The study was partially funded by the "Accion Transversal del Cancer", approved by the Spanish Ministry Council on 11 October 2007, by the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/1359, PI09/00773, PI09/01286, PI09/01903, PI09/02078, PI09/01662, PI11/01403, PI11/01889, PI12/00265), the FundaciĆ³n MarquĆ©s de Valdecilla (API 10/09), the Junta de Castilla y LeĆ³n (LE22A10-2), the ConsejerĆa de Salud of the Junta de AndalucĆa (2009-S0143), the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10), the Recercaixa (2010ACUP 00310), the Regional government
of the Basque Country, the ConsejerĆa de Sanidad de la RegiĆ³n de Murcia, the European Commission grants
FOOD-CT-2006ā036224-HIWATE, the Spanish Association Against Cancer (AECC) Scientific Foundation, the Catalan Government DURSI grant 2014SGR647, the support of the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia (2017SGR1085), the FundaciĆ³n Caja de Ahorros de Asturias and by the University of Oviedo. MCT is funded by a RamĆ³n y Cajal fellowship (RYC-2017-01892) from the Spanish Ministry of Science, Innovation and Universities and co-funded by the
European Social Fund. We acknowledge support from
the Spanish Ministry of Science and Innovation through the āCentro de Excelencia Severo Ochoa 2019-2023ā Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program. Statistical assistance provided by Ana Espinosa Morano was greatly appreciated
Promise and pitfalls in the application of big data to occupational and environmental health
EditorialIs ābig dataā merely a catchphrase, or does the approach
hold real promise in informing occupational and environmental
health? Can challenges related to messy and unrepresentative
data and spurious findings be overcome
Greater coordination and harmonisation of European occupational cohorts is needed
Paid employment is an essential component of adult life and a major determinant of health. However, underemployment, long-term unemployment, poor working conditions and a lack of job security all negatively affect health, may hinder economic growth and further increase inequalities in the population. Occupational exposures are related to a significant proportion of diseases including cancer, cardiorespiratory diseases and musculoskeletal and mental disorders, among others.1 The demographic shift, with an ageing and increasingly diverse workforce, makes the impact of work on healthy ageing and disease prognosis a key issue. Rapid changes in employment patterns and exposures along with occupational restructuring and the increasing use of new technologies further increase the importance of research in occupational health
Reporting of conflicts of interest from drug trials in Cochrane reviews:cross sectional study
Objectives To investigate the degree to which Cochrane reviews of drug interventions published in 2010 reported conflicts of interest from included trials and, among reviews that reported this information, where it was located in the review documents. Design Cross sectional study. Data sources Cochrane Database of Systematic Reviews. Selection criteria Systematic reviews of drug interventions published in 2010 in the Cochrane Database of Systematic Reviews, with review content classified as up to date in 2008 or later and with results from one or more randomised controlled trials. Results Of 151 included Cochrane reviews, 46 (30%, 95% confidence interval 24% to 38%) reported information on the funding sources of included trials, including 30 (20%, 14% to 27%) that reported information on trial funding for all included trials and 16 (11%, 7% to 17%) that reported for some, but not all, trials. Only 16 of the 151 Cochrane reviews (11%, 7% to 17%) provided any information on trial author-industry financial ties or trial author-industry employment. Information on trial funding and trial author-industry ties was reported in one to seven locations within each review, with no consistent reporting location observed. Conclusions Most Cochrane reviews of drug trials published in 2010 did not provide information on trial funding sources or trial author-industry financial ties or employment. When this information was reported, location of reporting was inconsistent across reviews
Nutrient-specific solubility patterns of leaf litter across 41 lowland tropical woody species
Abstract. Leaching is a mechanism for the release of nutrients from litter or senesced leaves that can drive interactions among plants, microbes, and soil. Although leaching is well established in conceptual models of litter decomposition, potential nutrient solubility of mineral elements from recently senesced litter has seldom been quantified. Using a standardized extraction (1:50 litter-to-water ratio and four-hour extraction) and recently senesced leaf litter of 41 tropical tree and liana species, we investigated how solubility varies among elements, and whether the solubility of elements could be predicted by litter traits (e.g., lignin, total element concentrations). In addition, we investigated nutrient forms (i.e., inorganic and organic) and ratios in leachate. Water-soluble elements per unit litter mass were strongly predicted by total initial litter element concentrations for potassium (K; r 2 Ā¼ 0.79), sodium (Na; r 2 Ā¼ 0.51) and phosphorus (P; r 2 Ā¼ 0.66), while a significant but weaker positive relationship was found for nitrogen (N; r 2 Ā¼ 0.36). There was no significant relationship for carbon (C) or calcium (Ca). Element-specific solubility varied markedly. On average 100% of total K, 35% of total P, 28% of total Na, 5% of total N, 4% of total Ca, and 3% of total C were soluble. For soluble P, 90% was inorganic orthophosphate. The high solubility of K, Na, and P as inorganic orthophosphate suggests that these nutrients can become rapidly available to litter microbes with no metabolic cost. Few common predictors of decomposition rates were correlated with element solubility, although soluble C (milligrams per gram of litter) was negatively related to lignin content (r 2 Ā¼ 0.19; P , 0.004). Solubility of elements was linked within a species: when a species ranked high in the soluble fraction of one element, it also ranked high in the solubility of other elements. Overall nutrient-specific patterns of solubility from recently senesced litter emphasize that litter elements cannot be treated equally in our conceptual and empirical models of decomposition. The relatively high potential solubility of P as orthophosphate from fresh litter advances our understanding of ecological stoichiometric ratios and nutrient bioavailability in tropical forests
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