282 research outputs found
How nanotechnology-enabled concepts could contribute to the prevention, diagnosis and therapy of bacterial infections
Concepts of health and well-being in managers: An organizational study
Global changes and new managerial challenges require new concepts of health and well-being in organizational contexts. In the South African context, health and well-being of managers have gained relevance in organizations and in management sciences. International organizations, in particular, attempt to address the increasing demand for health care and the delivery of health services to their managers. Careful and appropriate health management requires research to evaluate context-specific health concepts and strategies. The purpose and aim of this article is to assess managerial concepts on health and well-being that could be used by the organization to contribute to managerial well-being by implementing health promotion according to managerial needs. At the same time, this article contributes to salutogenetic health research that is very rare with regard to the South African organizational management research
Detection of mesenchymal stem cells senescence by prelamin A accumulation at the nuclear level
Improving the clinical potential of ultra-high field fMRI using a model-free analysis method based on response consistency
Peanut‐induced anaphylaxis in children and adolescents: Data from the European Anaphylaxis Registry
Background Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%-1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents. Methods Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre. Results 3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004). Conclusions The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition
Large Scale Searches for Brown Dwarfs and Free-Floating Planets
Searches of large scale surveys have resulted in the discovery of over 1000
brown dwarfs in the Solar neighbourhood. In this chapter we review the progress
in finding brown dwarfs in large datasets, highlighting the key science goals,
and summarising the surveys that have contributed most significantly to the
current sample.Comment: Accepted to appear in the Handbook of Exoplanets (Springer); Editors:
Hans J. Deeg & Juan Antonio Belmont
Further Defining Spectral Type "Y" and Exploring the Low-mass End of the Field Brown Dwarf Mass Function
We present the discovery of another seven Y dwarfs from the Wide-field
Infrared Survey Explorer (WISE). Using these objects, as well as the first six
WISE Y dwarf discoveries from Cushing et al., we further explore the transition
between spectral types T and Y. We find that the T/Y boundary roughly coincides
with the spot where the J-H colors of brown dwarfs, as predicted by models,
turn back to the red. Moreover, we use preliminary trigonometric parallax
measurements to show that the T/Y boundary may also correspond to the point at
which the absolute H (1.6 um) and W2 (4.6 um) magnitudes plummet. We use these
discoveries and their preliminary distances to place them in the larger context
of the Solar Neighborhood. We present a table that updates the entire stellar
and substellar constituency within 8 parsecs of the Sun, and we show that the
current census has hydrogen-burning stars outnumbering brown dwarfs by roughly
a factor of six. This factor will decrease with time as more brown dwarfs are
identified within this volume, but unless there is a vast reservoir of cold
brown dwarfs invisible to WISE, the final space density of brown dwarfs is
still expected to fall well below that of stars. We also use these new Y dwarf
discoveries, along with newly discovered T dwarfs from WISE, to investigate the
field substellar mass function. We find that the overall space density of
late-T and early-Y dwarfs matches that from simulations describing the mass
function as a power law with slope -0.5 < alpha < 0.0; however, a power-law may
provide a poor fit to the observed object counts as a function of spectral type
because there are tantalizing hints that the number of brown dwarfs continues
to rise from late-T to early-Y. More detailed monitoring and characterization
of these Y dwarfs, along with dedicated searches aimed at identifying more
examples, are certainly required.Comment: 91 pages, 15 figures, accepted for publication in The Astrophysical
Journa
First light of the VLT planet finder SPHERE IV : Physical and chemical properties of the planets around HR8799
This is a pre-copyedited, author produced PDF of an article accepted for publication in Astronomy & Astrophysics following peer review. Subject to 12 month's embargo period. Embargo end date: 16 February 2017. The version of record [Bonnefoy, M., 'First light of the VLT planet finder SPHERE, IV. Physical and chemical properties of the planets around HR8799', A&A, 587, A58 (2016), first published online 16 February 2016] is available online at doi http://dx.doi.org/10.1051/0004-6361/201526906Context. The system of four planets discovered around the intermediate-mass star HR8799 offers a unique opportunity to test planet formation theories at large orbital radii and to probe the physics and chemistry at play in the atmospheres of self-luminous young (∼30 Myr) planets. We recently obtained new photometry of the four planets and low-resolution (R∼30) spectra of HR8799 d and e with the SPHERE instrument (paper III). Aims. In this paper (paper IV), we aim to use these spectra and available photometry to determine how they compare to known objects, what the planet physical properties are, and how their atmospheres work. Methods. We compare the available spectra, photometry, and spectral-energy distribution (SED) of the planets to field dwarfs and young companions. In addition, we use the extinction from corundum, silicate (enstatite and forsterite), or iron grains likely to form in the atmosphere of the planets to try to better understand empirically the peculiarity of their spectrophotometric properties. To conclude, we use three sets of atmospheric models (BT-SETTL14, Cloud-AE60, Exo-REM) to determine which ingredients are critically needed in the models to represent the SED of the objects, and to constrain their atmospheric parameters (T eff , log g, M/H). Results. We find that HR8799d and e properties are well reproduced by those of L6-L8 dusty dwarfs discovered in the field, among which some are candidate members of young nearby associations. No known object reproduces well the properties of planets b and c. Nevertheless, we find that the spectra and WISE photometry of peculiar and/or young early-T dwarfs reddened by submicron grains made of corundum, iron, enstatite, or forsterite successfully reproduce the SED of these planets. Our analysis confirms that only the Exo-REM models with thick clouds fit (within 2σ) the whole set of spectrophotometric datapoints available for HR8799 d and e for T eff = 1200 K, log g in the range 3.0-4.5, and M/H=+0.5. The models still fail to reproduce the SED of HR8799c and b. The determination of the metallicity, log g, and cloud thickness are degenerate. Conclusions. Our empirical analysis and atmospheric modelling show that an enhanced content in dust and decreased CIA of H2 is certainly responsible for the deviation of the properties of the planet with respect to field dwarfs. The analysis suggests in addition that HR8799c and b have later spectral types than the two other planets, and therefore could both have lower masses.Peer reviewe
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