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The extremely rapid assembly of the earliest galaxies during the first billion years of cosmic history is a major challenge for our understanding of galaxy formation physics1-5. The advent of the James Webb Space Telescope (JWST) has exacerbated this issue by confirming the existence of galaxies in substantial numbers as early as the first few hundred million years6-8. Perhaps even more surprisingly, in some galaxies, this initial highly efficient star formation rapidly shuts down, or quenches, giving rise to massive quiescent galaxies as little as 1.5 billion years after the Big Bang9,10. However, due to their faintness and red colour, it has proven extremely challenging to learn about these extreme quiescent galaxies, or to confirm whether any existed at earlier times. Here we report the spectroscopic confirmation of a massive quiescent galaxy, GS-9209, at redshift, z = 4.658, just 1.25 billion years after the Big Bang, using the JWST Near-Infrared Spectrograph (NIRSpec). From these data we infer a stellar mass of M* = 3.8 ± 0.2 × 1010 Mâ, which formed over a roughly 200 Myr period before this galaxy quenched its star-formation activity at [Formula: see text], when the Universe was approximately 800 Myr old. This galaxy is both a likely descendent of the highest-redshift submillimetre galaxies and quasars, and a likely progenitor for the dense, ancient cores of the most massive local galaxies.
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Objectives: Evaluate diagnostic accuracy and feasibility of a mail-out home oximetry kit. Design: Patients were referred for both the tertiary/quaternary-centre hospital-delivered oximetry (HDO) and for the mail-out remotely-delivered oximetry (RDO). Quantitative and qualitative data were collected. The COVID-19 pandemic began during this study; therefore, necessary methodological adjustments were implemented. Setting: Patients were first evaluated in Swan Hill, Victoria. RDO kits were sent to home addresses. For the HDO, patients travelled to the Melbourne city area, received the kit, stayed overnight, and returned the kit the following morning. Participants: All consecutive paediatric patients (aged 2−18), diagnosed by a specialist in Swan Hill with obstructive sleep apnoea (OSA) on history/examination, and booked for tonsillectomy +/− adenoidectomy, were recruited. Main outcome measures: Diagnostic accuracy (i.e., comparison of RDO to HDO results) and test delivery time (i.e., days from consent signature to oximetry delivery) were recorded. Patient travel distances for HDO collection were calculated using home/delivery address postcodes and Google® Maps data. Qualitative data were collected with two digital follow-up surveys. Results: All 32 patients that had both the HDO and RDO had identical oximetry results. The HDO mean delivery time was 87.7 days, while the RDO mean delivery time was 23.6 days (p value: <0.001). Qualitatively, 3/28 preferred the HDO, while 25/28 preferred the RDO (n = 28). Conclusions: The remote option is as accurate as the hospital option, strongly preferred by patients, more rapidly completed, and also an ideal investigation delivery method during certain emergencies, such as the COVID-19 pandemic.
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The question of when and why societies have transitioned away from matriliny to other types of kinship systems-and when and why they transition towards matriliny-has a long history in anthropology, one that is heavily engaged with both evolutionary theory and cross-cultural research methods. This article presents tabulations from a new coding of ethnographic documents from the Standard Cross-Cultural Sample (SCCS), tallying claims of transitions in kinship systems both away from and to matriliny using various levels of stringency. We then use our counts as the outcome variables in a set of Bayesian analyses that simultaneously estimate the probability of a transition occurring given societal covariates alongside the conditional probability of detecting a transition given the volume of ethnographic data available to code. Our goal is to estimate the cross-cultural and comparative frequency of transitions away from and to matriliny, as well as to explore potential causes underlying these patterns. We find that transitions away from matriliny have been significantly more common than 'reverse transitions' to matriliny. Our evidence suggests that both rates may be, in part, an artefact of the colonial and globalizing period during which the data comprising much of the current ethnographic record were recorded. Analyses of the correlates of transitions away from matriliny are consistent with several of the key causal arguments made by anthropologists over the past century, especially with respect to subsistence transition (to pastoralism, intensive agriculture and market economies), social complexity and colonialism, highlighting the importance of ecological factors in such transitions. This article is part of the theme issue 'The evolution of female-biased kinship in humans and other mammals'.
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Comparación Transcultural , Hombres/psicología , Conducta Social , Mujeres/psicología , Teorema de Bayes , Evolución Cultural , Relaciones Familiares , Femenino , Humanos , Madres/psicologíaRESUMEN
The International Dysphagia Diet Standardisation Initiative (IDDSI) flow test, using a standard 10-mL syringe, is being adopted in many countries for clinical measurement of the consistency of drinks. The working hypothesis is that thickening drinks to retard flow can be advantageous for individuals who struggle to cope with thin drinks. This study assesses how the IDDSI test relates to rheology and clinical knowledge of physiological flows during swallowing. With no pre-existing analytical solution for internal flow through the syringe, a computational model was designed, incorporating rheometry data from a variety of Newtonian and non-Newtonian liquids. The computational model was validated experimentally across the range of liquids but the technique showed limitations in simulating dripping and cohesiveness. Gum-based liquids which were strongly shear-thinning (0.12 < n < 0.25) showed plug-flow characteristics with 90% of the shear occurring in only 22% of the radial dimension. Shear rates were maximal at the nozzle outlet (> 60 times higher than the barrel) and reached 7400/s for the thinnest gum-based liquid. Shear rheology data alone was unable to describe the flow of these drinks. The flow conditions in the test varied according to the type and consistency of liquid, relating to the desired clinical effect.
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Simulación por Computador , Trastornos de Deglución , Deglución , Reología/métodos , Humanos , Modelos Teóricos , ViscosidadRESUMEN
Since regular radio broadcasts started in the 1920s, the exposure to human-made electromagnetic fields has steadily increased. These days we are not only exposed to radio waves but also other frequencies from a variety of sources, mainly from communication and security devices. Considering that nearly all biological systems interact with electromagnetic fields, understanding the affects is essential for safety and technological progress. This paper systematically reviews the role and effects of static and pulsed radio frequencies (100-109 Hz), millimetre waves (MMWs) or gigahertz (109-1011 Hz), and terahertz (1011-1013 Hz) on various biomolecules, cells and tissues. Electromagnetic fields have been shown to affect the activity in cell membranes (sodium versus potassium ion conductivities) and non-selective channels, transmembrane potentials and even the cell cycle. Particular attention is given to millimetre and terahertz radiation due to their increasing utilization and, hence, increasing human exposure. MMWs are known to alter active transport across cell membranes, and it has been reported that terahertz radiation may interfere with DNA and cause genomic instabilities. These and other phenomena are discussed along with the discrepancies and controversies from published studies.