58 research outputs found
Recommended from our members
Analysis of the African coelacanth genome sheds light on tetrapod evolution
It was a zoological sensation when a living specimen of the coelacanth was first discovered in 1938, as this lineage of lobe-finned fish was thought to have gone extinct 70 million years ago. The modern coelacanth looks remarkably similar to many of its ancient relatives, and its evolutionary proximity to our own fish ancestors provides a glimpse of the fish that first walked on land. Here we report the genome sequence of the African coelacanth, Latimeria chalumnae. Through a phylogenomic analysis, we conclude that the lungfish, and not the coelacanth, is the closest living relative of tetrapods. Coelacanth protein-coding genes are significantly more slowly evolving than those of tetrapods, unlike other genomic features . Analyses of changes in genes and regulatory elements during the vertebrate adaptation to land highlight genes involved in immunity, nitrogen excretion and the development of fins, tail, ear, eye, brain, and olfaction. Functional assays of enhancers involved in the fin-to-limb transition and in the emergence of extra-embryonic tissues demonstrate the importance of the coelacanth genome as a blueprint for understanding tetrapod evolution
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
Mid-Latitude Temperatures at 87 km: Results From Multi-Instrument Fourier Analysis
Using a novel Fourier fitting method we combine two years of mid-latitude temperature measurements at 87 km from the High Resolution Doppler Imager, the Colorado State University lidar, and the Peach Mountain Interferometer. After accounting for calibration bias, significant local-time variations on the order of 10 K were observed. Stationary planetary waves with amplitudes up to 10 K were observed during winter, with weaker wave amplitudes occurring during other seasons. Because of calibration biases among these instruments, we could estimate the annual mean temperature to no better than 193.5 plus or minus 8.5 K
A co-templating route to the synthesis of Cu SAPO STA-7, giving an active catalyst for the selective catalytic reduction of NO
Copper cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and tetraethylammonium (TEA(+)) act as co-templates for the hydrothermal crystallisation of the silicoaluminophosphate SAPO STA-7, as determined by UV-visible, ESR and solid-state MAS NMR spectroscopies, powder and single crystal X-ray diffraction and chemical analysis. Calcination of the as-prepared solid in flowing oxygen removes all organics to leave Cu(II),H-SAPO STA-7 (hereafter Cu-SAPO STA-7) in which the presence of bridging hydroxyl groups is confirmed by IR and the presence of multiple environments for Cu2+ is shown by IR using NO as a probe molecule. Rietveld analysis of synchrotron X-ray powder diffraction data collected over the temperature range 293-673 K locates Cu2+ cations distributed over four sites: above six membered rings (6MRs) and in the three different 8MR windows of the STA-7 structure. Cu-SAPO STA-7 is a very good catalyst for the selective catalytic reduction of NO with NH3, in the presence or absence of water vapour, so that this approach represents an efficient and effective route to copper-containing SAPO catalysts that obviates the need for an aqueous Cu2+ ion exchange step during preparation. (C) 2011 Elsevier Inc. All rights reserved.</p
A co-templating route to the synthesis of Cu SAPO STA-7, giving an active catalyst for the selective catalytic reduction of NO
International audienceCopper cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and tetraethylammonium (TEA(+)) act as co-templates for the hydrothermal crystallisation of the silicoaluminophosphate SAPO STA-7, as determined by UV-visible, ESR and solid-state MAS NMR spectroscopies, powder and single crystal X-ray diffraction and chemical analysis. Calcination of the as-prepared solid in flowing oxygen removes all organics to leave Cu(II),H-SAPO STA-7 (hereafter Cu-SAPO STA-7) in which the presence of bridging hydroxyl groups is confirmed by IR and the presence of multiple environments for Cu2+ is shown by IR using NO as a probe molecule. Rietveld analysis of synchrotron X-ray powder diffraction data collected over the temperature range 293-673 K locates Cu2+ cations distributed over four sites: above six membered rings (6MRs) and in the three different 8MR windows of the STA-7 structure. Cu-SAPO STA-7 is a very good catalyst for the selective catalytic reduction of NO with NH3, in the presence or absence of water vapour, so that this approach represents an efficient and effective route to copper-containing SAPO catalysts that obviates the need for an aqueous Cu2+ ion exchange step during preparation. (C) 2011 Elsevier Inc. All rights reserved
Lack of strategic funding and long-term job security threaten to have profound effects on cardiovascular researcher retention in Australia
BackgroundCardiovascular disease is the leading cause of death in Australia. Investment in research solutions has been demonstrated to yield health and a 9.8-fold return economic benefit. The sector, however, is severely challenged with success rates of traditional peer-reviewed funding in decline. Here, we aimed to understand the perceived challenges faced by the cardiovascular workforce in Australia prior to the COVID-19 pandemic.MethodsWe used an online survey distributed across Australian cardiovascular societies/councils, universities and research institutes over a period of 6 months during 2019, with 548 completed responses. Inclusion criteria included being an Australian resident or an Australian citizen who lived overseas, and a current or past student or employee in the field of cardiovascular research.ResultsThe mean age of respondents was 42±13 years, 47% were male, 85% had a full-time position, and 40% were a group leader or laboratory head. Twenty-three per cent (23%) had permanent employment, and 82% of full-time workers regularly worked >40 hours/week. Sixty-eight per cent (68%) said they had previously considered leaving the cardiovascular research sector. If their position could not be funded in the next few years, a staggering 91% of respondents would leave the sector. Compared to PhD- and age-matched men, women were less likely to be a laboratory head and to feel they had a long-term career path as a cardiovascular researcher, while more women were unsure about future employment and had considered leaving the sector (all
- âŠ