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By using an ultradeep JWST/MIRI image at 5.6 μ m in the Hubble eXtreme Deep Field, we constrain the role of strong H α emitters (HAEs) during "cosmic reionization" at z ≃ 7–8. Our sample of HAEs is comprised of young (<35 Myr) galaxies, except for one single galaxy (≈300 Myr), with low stellar masses (≲109 M ⊙). These HAEs show a wide range of rest-frame UV continuum slopes (β), with a median value of β = −2.15 ± 0.21, which broadly correlates with stellar mass. We estimate the ionizing photon production efficiency (ξ ion,0) of these sources (assuming f esc,LyC = 0%), which yields a median value log 10 (ξ ion , 0 / (Hz erg − 1)) = 25.50 − 0.12 + 0.10 . We show that ξ ion,0 positively correlates with H α equivalent width and specific star formation rate. Instead ξ ion,0 weakly anticorrelates with stellar mass and β. Based on the β values, we predict f esc , LyC = 4 % − 2 + 3 , which results in log 10 (ξ ion / (Hz erg − 1)) = 25.55 − 0.13 + 0.11 . Considering this and related findings from the literature, we find a mild evolution of ξ ion with redshift. Additionally, our results suggest that these HAEs require only modest escape fractions (f esc,rel) of 6%–15% to reionize their surrounding intergalactic medium. By only considering the contribution of these HAEs, we estimated their total ionizing emissivity ( N ̇ ion ) as N ̇ ion = 10 50.53 ± 0.45 s − 1 Mpc − 3 . When comparing their N ̇ ion with non-HAE galaxies across the same redshift range, we find that that strong, young, and low-mass emitters may have played an important role during cosmic reionization. [ABSTRACT FROM AUTHOR]

Context. Epiphytes are typically associated with wet forests and are seldom documented in drylands. This absence is presumed to reflect moisture limitations to their establishment and survival. Aims. In response to a large body of epiphyte observations made by a pastoralist in collaboration with local Indigenous people, we investigated and documented an unusually high concentration of woody epiphytes from semi-arid eastern Australia and describe this in relation to ecological and cultural factors. Methods. We searched for, recorded and measured epiphytic trees and shrubs in semi-arid eucalypt woodlands of northern New South Wales and southern Queensland. Factors influencing their distribution were examined. Key results. Eucalypts growing along the Barwon River palaeochannels host 21 species of shrubs and trees. Over 95% of the 712 woody epiphytes documented were alive, and some appeared decades old; 70% were growing in trees that had been modified by humans, and at least half of the host sites were directly anthropogenically created. Epiphytes are widely, but typically sparsely, distributed in other semi-arid eucalypt woodlands, with a further 311 found during regional surveys. Conclusions. The large trees of the Barwon palaeochannels, their extensive human modification to create favourable sites for epiphyte establishment, and the diversity of understorey shrubs providing a propagule source have combined to create this epiphyte-rich woodland. Their association with Culturally Modified Trees and the relatively low density of epiphytes elsewhere suggest that Aboriginal people have played a direct role in creating this landscape, to which they remain deeply connected. Implications. Epiphytes may be more widespread in drylands than previously recognised.We hope that this study stimulates further research on their distribution, characteristics, and ecological and cultural associations. [ABSTRACT FROM AUTHOR]

Author(s): S. C. Singh (corresponding author) [1, 2]; A. J. Harding [3]; G. M. Kent [3]; M. C. Sinha [4]; V. Combier [1]; S. Bazin [1]; C. H. Tong [2]; [...]

Author(s): G. M. Kent (corresponding author) [1]; S. C. Singh [2, 3, 4]; A. J. Harding [1]; M. C. Sinha [3, 4]; J. A. Orcutt [1]; P. J. Barton [4]; [...]

Health and social care professionals are required to work together to deliver person-centered care. Professionals therefore find themselves making decisions within multidisciplinary teams. For educators, there has been a call to bring students from differing professions together to learn to enable more effective teamwork, interprofessional communication, and collaborative practice. This multidisciplinary working is complicated by the increasingly complex nature of ethical dilemmas that health and social care professionals face. It is therefore widely recognized that the teaching and learning of ethics within health and social care courses is valuable. In this paper, we briefly make the case in support of teaching and learning health and social care ethics through the medium of interprofessional education (IPE). The purpose of this paper is to provide guidance to educators intending to design ethics-orientated IPE for health and social care students. The guidance is based on the ongoing experiences of designing and implementing ethics-orientated IPE across five departments within two universities located in the North of England over a five-year period. Descriptions of the ethics-orientated IPE activities are included in the guide, along with key resources recommended. [ABSTRACT FROM AUTHOR]

Context. Quasi-periodic pulsations (QPPs) are time variations in the energy emission during a flare that are observed on both the Sun and other stars and thus have the potential to link the physics of solar and stellar flares. Aims. We characterise the QPPs detected in an X-ray flare on the solar analogue, EK Draconis, which was observed by XMM-Newton. Methods. We used wavelet and autocorrelation techniques to identify the QPPs in a detrended version of the flare. We also fitted a model to the flare based on an exponential decay combined with a decaying sinusoid. The flare is examined in multiple energy bands. Results. A statistically significant QPP is observed in the X-ray energy band of 0.2–12.0 keV with a periodicity of 76 ± 2 min. When this energy band is split, a statistically significant QPP is observed in the low-energy band (0.2–1.0 keV) with a periodicity of 73 ± 2 min and in the high-energy band (1.0–12.0 keV) with a periodicity of 82 ± 2 min. When fitting a model to the time series the phases of the signals are also found to be significantly different in the two energy bands (with a difference of 1.8 ± 0.2 rad) and the high-energy band is found to lead the low-energy band. Furthermore, the first peak in the cross-correlation between the detrended residuals of the low- and high-energy bands is offset from zero by more than 3σ (4.1 ± 1.3 min). Both energy bands produce statistically significant regions in the wavelet spectrum, whose periods are consistent with those listed above. However, the peaks are broad in both the wavelet and global power spectra, with the wavelet showing evidence for a drift in period with time, and the difference in period obtained is not significant. The offset in the first peak in the cross-correlation of the detrended residuals of two non-congruent energy bands (0.5−1.0 keV and 4.5−12.0 keV) is found to be even larger (10 ± 2 min). However, the signal-to-noise in the higher of these two energy-bands, covering the range 4.5−12.0 keV, is low. Conclusions. The presence of QPPs similar to those observed on the Sun, and other stars, suggests that the physics of flares on this young solar analogue is similar to the physics of solar flares. It is possible that the differences in the QPPs detected in the two energy bands are seen because each band observes a different plasma structure. However, the phase difference, which differs more significantly between the two energy bands than the period, could also be explained in terms of the Neupert effect. This suggests that QPPs are caused by the modulation of the propagation speeds of charged particles. [ABSTRACT FROM AUTHOR]

The James Webb Space Telescope (JWST) will provide deep imaging and spectroscopy for sources at redshifts above 6, covering the entire Epoch of Reionization (EoR, 6 <  z <  10), and enabling the detailed exploration of the nature of the different sources during the first 1 Gyr of the history of the Universe. The Medium Resolution Spectrograph (MRS) of the mid-IR Instrument (MIRI) will be the only instrument on board JWST able to observe the brightest optical emission lines Hα and [OIII]0.5007 μm at redshifts above 7 and 9, respectively, providing key insights into the physical properties of sources during the early phases of the EoR. This paper presents a study of the Hα fluxes predicted by state-of-the-art FIRSTLIGHT cosmological simulations for galaxies at redshifts of 6.5–10.5, and its detectability with MIRI. Deep (40 ks) spectroscopic integrations with MRS will be able to detect (signal-to-noise ratio > 5) EoR sources at redshifts above 7 with intrinsic star formation rates (SFR) of more than 2 M⊙ yr−1, and stellar masses above 4–9 × 107M⊙. These limits cover the upper end of the SFR and stellar mass distribution at those redshifts, representing ∼6% and ∼1% of the predicted FIRSTLIGHT population at the 6.5–7.5 and 7.5–8.5 redshift ranges, respectively. In addition, the paper presents realistic MRS simulated observations of the expected rest-frame optical and near-infrared spectra for some spectroscopically confirmed EoR sources recently detected by ALMA as [OIII]88 μm emitters. The MRS simulated spectra cover a wide range of low metallicities from about 0.2–0.02 Z⊙, and different [OIII]88 μm/[OIII]0.5007 μm line ratios. The simulated 10 ks MRS spectra show S/N in the range of 5–90 for Hβ, [OIII]0.4959,0.5007 μm, Hα and HeI1.083 μm emission lines of the currently highest spectroscopically confirmed EoR (lensed) source MACS1149-JD1 at a redshift of 9.11, independent of metallicity. In addition, deep 40 ksec simulated spectra of the luminous merger candidate B14-65666 at 7.15 shows the MRS capabilities of detecting, or putting strong upper limits on, the weak [NII]0.6584 μm, [SII]0.6717,0.6731 μm, and [SIII]0.9069,0.9532 μm emission lines. These observations will provide the opportunity of deriving accurate metallicities in bright EoR sources using the full range of rest-frame optical emission lines up to 1 μm. In summary, MRS will enable the detailed study of key physical properties such as internal extinction, instantaneous star formation, hardness of the ionizing continuum, and metallicity in bright (intrinsic or lensed) EoR sources. [ABSTRACT FROM AUTHOR]

Summary: Nephrosplenic entrapment is a commonly diagnosed cause of acute colic that may be corrected using surgical or non‐surgical methods and has a good prognosis for survival. Intravenous administration of phenylephrine at doses ranging from 20–60 μg/kg given over 5–15 min often followed by forced exercise, various rolling techniques under general anaesthesia, or a combination of therapies has been reported. Correction of the entrapment via exploratory celiotomy may be challenging in certain cases and is hampered by marked splenic enlargement. The case report by Loomes and Anderson (2019) in this issue described a novel method of reducing the size of the spleen by direct intra‐splenic injection of phenylephrine, in a case non‐responsive to intravenous phenylephrine administration, which facilitated surgical correction of the nephrosplenic entrapment. [ABSTRACT FROM AUTHOR]