719 research outputs found

    Paediatric intensive care admissions of preterm children born <32 weeks gestation: a national retrospective cohort study using data linkage

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    Objective: Survival of babies born very preterm (<32 weeks gestational age) has increased, although preterm-born children may have ongoing morbidity. We aimed to investigate the risk of admission to paediatric intensive care units (PICUs) of children born very preterm following discharge home from neonatal care. Design: Retrospective cohort study, using data linkage of National Neonatal Research Database and the Paediatric Intensive Care Audit Network datasets. Setting: All neonatal units and PICUs in England and Wales. Patients: Children born very preterm between 1 January 2013 and 31 December 2018 and admitted to neonatal units. Main outcome measures: Admission to PICU after discharge home from neonatal care, before 2 years of age. Results: Of the 40 690 children discharged home from neonatal care, there were 2308 children (5.7%) with at least one admission to PICU after discharge. Of these children, there were 1901 whose first PICU admission after discharge was unplanned. The percentage of children with unplanned PICU admission varied by gestation, from 10.2% of children born <24 weeks to 3.3% born at 31 weeks. Following adjustment, unplanned PICU admission was associated with lower gestation, male sex (adjusted OR (aOR) 0.79), bronchopulmonary dysplasia (aOR 1.37), necrotising enterocolitis requiring surgery (aOR 1.39) and brain injury (aOR 1.42). For each week of increased gestation, the aOR was 0.90. Conclusions: Most babies born <32 weeks and discharged home from neonatal care do not require PICU admission in the first 2 years. The odds of unplanned admissions to PICU were greater in the most preterm and those with significant neonatal morbidity. Data availability statement: Data may be obtained from a third party and are not publicly available. Data may be obtained from a third party and are not publicly available. PICANet data may be requested from the data controller, the Healthcare Quality Improvement Partnership (HQIP). A Data Access Request Form can be obtained from https://www.hqip.org.uk/national-programmes/accessing-ncapop-data/%23.XQeml_lKhjU

    Deeply Embedded Protostellar Population in the Central Molecular Zone Suggested by H2_2O Masers and Dense Cores

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    The Central Molecular Zone (CMZ), usually referring to the inner 500 pc of the Galaxy, contains a dozen of massive (105\sim10^5 MM_\odot) molecular clouds. Are these clouds going to actively form stars like Sgr B2? How are they affected by the extreme physical conditions in the CMZ, such as strong turbulence? Here we present a first step towards answering these questions. Using high-sensitivity, high angular resolution radio and (sub)millimeter observations, we studied deeply embedded star formation in six massive clouds in the CMZ, including the 20 and 50 km s1^{-1} clouds, Sgr B1 off (as known as dust ridge clouds e/f), Sgr C, Sgr D, and G0.253-0.016. The VLA water maser observations suggest a population of deeply embedded protostellar candidates, many of which are new detections. The SMA 1.3 mm continuum observations reveal peaks in dust emission associated with the masers, suggesting the existence of dense cores. While our findings confirm that clouds such as G0.253-0.016 lack internal compact substructures and are quiescent in terms of star formation, two clouds (the 20 km s1^{-1} cloud and Sgr C) stand out with clusters of water masers with associated dense cores which may suggest a population of deeply embedded protostars at early evolutionary phases. Follow-up observations with VLA and ALMA are necessary to confirm their protostellar nature

    'The Brick' is not a brick : A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016

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    © 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.In this paper we provide a comprehensive description of the internal dynamics of G0.253+0.016 (a.k.a. 'the Brick'); one of the most massive and dense molecular clouds in the Galaxy to lack signatures of widespread star formation. As a potential host to a future generation of high-mass stars, understanding largely quiescent molecular clouds like G0.253+0.016 is of critical importance. In this paper, we reanalyse Atacama Large Millimeter Array cycle 0 HNCO J=4(0,4)3(0,3)J=4(0,4)-3(0,3) data at 3 mm, using two new pieces of software which we make available to the community. First, scousepy, a Python implementation of the spectral line fitting algorithm scouse. Secondly, acorns (Agglomerative Clustering for ORganising Nested Structures), a hierarchical n-dimensional clustering algorithm designed for use with discrete spectroscopic data. Together, these tools provide an unbiased measurement of the line of sight velocity dispersion in this cloud, σvlos,1D=4.4±2.1\sigma_{v_{los}, {\rm 1D}}=4.4\pm2.1 kms1^{-1}, which is somewhat larger than predicted by velocity dispersion-size relations for the Central Molecular Zone (CMZ). The dispersion of centroid velocities in the plane of the sky are comparable, yielding σvlos,1D/σvpos,1D1.2±0.3\sigma_{v_{los}, {\rm 1D}}/\sigma_{v_{pos}, {\rm 1D}}\sim1.2\pm0.3. This isotropy may indicate that the line-of-sight extent of the cloud is approximately equivalent to that in the plane of the sky. Combining our kinematic decomposition with radiative transfer modelling we conclude that G0.253+0.016 is not a single, coherent, and centrally-condensed molecular cloud; 'the Brick' is not a \emph{brick}. Instead, G0.253+0.016 is a dynamically complex and hierarchically-structured molecular cloud whose morphology is consistent with the influence of the orbital dynamics and shear in the CMZ.Peer reviewedFinal Accepted Versio

    Chemical modeling of Infrared Dark Clouds: the Role of Surface Chemistry

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    We simulate the chemistry of infrared dark clouds (IRDCs) with a model in which the physical conditions are homogeneous and time-independent. The chemistry is solved as a function of time with three networks: one purely gas-phase, one that includes accretion and desorption, and one, the complete gas-grain network, that includes surface chemistry in addition. We compare our results with observed molecular abundances for two representative IRDCs -- IRDC013.90-1 and IRDC321.73-1 -- using the molecular species N2_2H+^+, HC3_3N, HNC, HCO+^+, HCN, C2_2H, NH3_3 and CS. IRDC013.90-1 is a cold IRDC, with a temperature below 20 K, while IRDC321.73-1 is somewhat warmer, in the range 20 - 30 K. We find that the complete gas-grain model fits the data very well, but that the goodness-of-fit is not sharply peaked at a particular temperature. Surface processes are important for the explanation of the high gas-phase abundance of N2_2H+^+ in IRDC321.73-1. The general success of the 0-D model in reproducing single-dish observations of our limited sample of 8 species shows that it is probably sufficient for an explanation of this type of data. To build and justify more complicated models, including spatial temperature and density structure, contraction, and heating, we require high-resolution interferometric data.Comment: accepted for publication in Ap

    Deeply Embedded Protostellar Population in the 20 km s-1 Cloud of the Central Molecular Zone

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    We report the discovery of a population of deeply embedded protostellar candidates in the 20 km s1^{-1} cloud, one of the massive molecular clouds in the Central Molecular Zone (CMZ) of the Milky Way, using interferometric submillimeter continuum and H2_2O maser observations. The submillimeter continuum emission shows five 1-pc scale clumps, each of which further fragments into several 0.1-pc scale cores. We identify 17 dense cores, among which 12 are gravitationally bound. Among the 18 H2_2O masers detected, 13 coincide with the cores and probably trace outflows emanating from the protostars. There are also 5 gravitationally bound dense cores without H2_2O maser detection. In total the 13 masers and 5 cores may represent 18 protostars with spectral types later than B1 or potential growing more massive stars at earlier evolutionary stage, given the non-detection in the centimeter radio continuum. In combination with previous studies of CH3_3OH masers, we conclude that the star formation in this cloud is at an early evolutionary phase, before the presence of any significant ionizing or heating sources. Our findings indicate that star formation in this cloud may be triggered by a tidal compression as it approaches pericenter, similar to the case of G0.253+0.016 but with a higher star formation rate, and demonstrate that high angular resolution, high sensitivity maser and submillimeter observations are a promising technique to unveil deeply embedded star formation in the CMZ

    PRIMA General Observer Science Book

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    PRIMA (The PRobe for-Infrared Mission for Astrophysics) is a concept for a far-infrared (IR) observatory. PRIMA features a cryogenically cooled 1.8 m diameter telescope and is designed to carry two science instruments enabling ultra-high sensitivity imaging and spectroscopic studies in the 24 to 235 microns wavelength range. The resulting observatory is a powerful survey and discovery machine, with mapping speeds better by 2 - 4 orders of magnitude with respect to its far-IR predecessors. The bulk of the observing time on PRIMA should be made available to the community through a General Observer (GO) program offering 75% of the mission time over 5 years. In March 2023, the international astronomy community was encouraged to prepare authored contributions articulating scientific cases that are enabled by the telescope massive sensitivity advance and broad spectral coverage, and that could be performed within the context of GO program. This document, the PRIMA General Observer Science Book, is the edited collection of the 76 received contributions.Comment: A. Moullet, T. Kataria, D. Lis, S. Unwin, Y. Hasegawa, E. Mills, C. Battersby, A. Roc, M. Meixner are the editors of the PRIMA General Observer Science Book. The book compiles 76 authored contributions. 399 page

    GAMBLINGLESS: FOR LIFE study protocol: a pragmatic randomised trial of an online cognitive–behavioural programme for disordered gambling

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    This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0

    Relationship between method of anastomosis and anastomotic failure after right hemicolectomy and ileo-caecal resection: an international snapshot audit

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    Aim The anastomosis technique used following right-sided colonic resection is widely variable and may affect patient outcome. This study aimed to assess the association between leak and anastomosis technique (stapled vs handsewn). Method This was a prospective, multicentre, international audit including patients undergoing elective or emergency right hemicolectomy or ileo-caecal resection operations over a 2-month period in early 2015. The primary outcome measure was the presence of anastomotic leak within 30 days of surgery, determined using a prespecified definition. Mixed effects logistic regression models were used to assess the association between leak and anastomosis method, adjusting for patient, disease and operative cofactors, with centre included as a random-effect variable. Results This study included 3208 patients, of whom 78.4% (n = 2515) underwent surgery for malignancy and 11.7% (n = 375) underwent surgery for Crohn's disease. An anastomosis was performed in 94.8% (n = 3041) of patients, which was handsewn in 38.9% (n = 1183) and stapled in 61.1% (n = 1858). Patients undergoing hand-sewn anastomosis were more likely to be emergency admissions (20.5% handsewn vs 12.9% stapled) and to undergo open surgery (54.7% handsewn vs 36.6% stapled). The overall anastomotic leak rate was 8.1% (245/3041), which was similar following handsewn (7.4%) and stapled (8.5%) techniques (P = 0.3). After adjustment for cofactors, the odds of a leak were higher for stapled anastomosis (adjusted OR = 1.43; 95% CI: 1.04-1.95; P = 0.03). Conclusion Despite being used in lower-risk patients, stapled anastomosis was associated with an increased anastomotic leak rate in this observational study. Further research is needed to define patient groups in whom a stapled anastomosis is safe.This is the peer-reviewed version of the article: Pinkney, T.; Battersby, N.; Bhangu, A.; Chaudhri, S.; El-Hussuna, A.; Frasson, M.; Nepogodiev, D.; Singh, B.; Kovačević, B.; Autora), (i Jos Puno. Relationship between Method of Anastomosis and Anastomotic Failure after Right Hemicolectomy and Ileo-Caecal Resection: An International Snapshot Audit. Colorectal Disease 2017, 19 (8), O296–O311. [https://doi.org/10.1111/codi.13646

    The RMS survey: ammonia mapping of the environment of massive young stellar objects

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    We present the results of ammonia observations towards 66 massive star forming regions identified by the Red Midcourse Space Experiment Source survey. We have used the Green Bank Telescope and the K-Band Focal Plane Array to map the ammonia (NH3) (1,1) and (2,2) inversion emission at a resolution of 30 arcsec in 8 arcmin regions towards the positions of embedded massive star formation. We have identified a total of 115 distinct clumps, approximately two-thirds of which are associated with an embedded massive young stellar object or compact H ii region, while the others are classified as quiescent. There is a strong spatial correlation between the peak NH3 emission and the presence of embedded objects. We derive the spatial distribution of the kinetic gas temperatures, line widths, and NH3 column densities from these maps, and by combining these data with dust emission maps we estimate clump masses, H2 column densities and ammonia abundances. The clumps have typical masses of ∼1000 M⊙ and radii ∼0.5 pc, line widths of ∼2 km s−1 and kinetic temperatures of ∼16–20 K. We find no significant difference between the sizes and masses of the star-forming and quiescent subsamples; however, the distribution maps reveal the presence of temperature and line width gradients peaking towards the centre for the star-forming clumps while the quiescent clumps show relatively uniform temperatures and line widths throughout. Virial analysis suggests that the vast majority of clumps are gravitationally bound and are likely to be in a state of global free fall in the absence of strong magnetic fields. The similarities between the properties of the two subsamples suggest that the quiescent clumps are also likely to form massive stars in the future, and therefore provide an excellent opportunity to study the initial conditions of massive pre-stellar and protostellar clumps

    Embodied Knowledge: Writing Researchers’ Bodies Into Qualitative Health Research

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    After more than a decade of postpositivist health care research and an increase in narrative writing practices, social scientific, qualitative health research remains largely disembodied. The erasure of researchers’ bodies from conventional accounts of research obscures the complexities of knowledge production and yields deceptively tidy accounts of research. Qualitative health research could benefit significantly from embodied writing that explores the discursive relationship between the body and the self and the semantic challenges of writing the body by incorporating bodily details and experiences into research accounts. Researchers can represent their bodies by incorporating autoethnographic narratives, drawing on all of their senses, interrogating the connections between their bodily signifiers and research processes, and experimenting with the semantics of self and body. The author illustrates opportunities for embodiment with excerpts from an ethnography of a geriatric oncology team and explores implications of embodied writing for the practice of qualitative health research
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