149 research outputs found
Single cell transcriptomics reveals specific RNA editing signatures in the human brain
While RNA editing by A-to-I deamination is a requisite for neuronal function in humans, it is under investigated in single cells. Here we fill this gap by analysing RNA editing profiles of single cells from the brain cortex of living human subjects. We show that RNA editing levels per cell are bimodally distributed and distinguish between major brain cell types thus providing new insights into neuronal dynamics
Understanding Super-Earths with MINERVA-Australis at USQ's Mount Kent Observatory
Super Earths, planets between 5-10 Earth masses, are the most common type of
exoplanet known, yet are completely absent from our Solar system. As a result,
their detailed properties, compositions, and formation mechanisms are poorly
understood. NASA's Transiting Exoplanet Survey Satellite (TESS) will identify
hundreds of Super-Earths orbiting bright stars, for the first time allowing
in-depth characterisation of these planets. At the University of Southern
Queensland, we are host to the MINERVA-Australis project, dedicated wholly to
the follow-up characterisation and mass measurement of TESS planets. We give an
update on the status of MINERVA-Australis and our expected performance.Comment: Accepted to appear in the peer-reviewed proceedings of the 17th
Australian Space Research Conference, held at the University of Sydney,
13th-15th November, 201
Recommended from our members
When Reporters get Hands-on with Robo-writing: Professionals Consider Automated Journalismâs Capabilities and Consequences
The availability of data feeds, the demand for news on digital devices, and advances in algorithms are helping to make automated journalism more prevalent. This article extends the literature on the subject by analysing professional journalistsâ experiences with, and opinions about, the technology. Uniquely, the participants were drawn from a range of news organizationsâincluding the BBC, CNN, and Thomson Reutersâand had first-hand experience working with robo-writing software provided by one of the leading technology suppliers. The results reveal journalistsâ judgements on the limitations of automation, including the nature of its sources and the sensitivity of its ânose for newsâ. Nonetheless, journalists believe that automated journalism will become more common, increasing the depth, breadth, specificity, and immediacy of information available. While some news organizations and consumers may benefit, such changes raise ethical and societal issues and, counter-intuitively perhaps, may increase the need for skillsânews judgement, curiosity, and scepticismâthat human journalists embody
Bioactive Trace Metals and Their Isotopes as Paleoproductivity Proxies: An Assessment Using GEOTRACES-Era Data
86 pages, 33 figures, 2 tables, 1 appendix.-- Data Availability Statement: The majority of the dissolved data were sourced from the GEOTRACES Intermediate Data Products in 2014 (Mawji et al., 2015) and 2017 (Schlitzer et al., 2018), and citations to the primary data sources are given in the caption for each figure. Data sources for Figure 1 are given below. Figure 1: Iron: Conway & John, 2014a (Atlantic); Conway & John, 2015a (Pacific); Abadie et al., 2017 (Southern). Zinc: Conway & John, 2014b (Atlantic); Conway & John, 2015a (Pacific); R. M. Wang et al., 2019 (Southern). Copper: Little et al., 2018 (Atlantic); Takano et al., 2017 (Pacific); Boye et al., 2012 (Southern). Cadmium: Conway and John, 2015b (Atlantic); Conway & John, 2015a (Pacific); Abouchami et al., 2014 (Southern). Molybdenum: Nakagawa et al., 2012 (all basins). Barium: Bates et al., 2017 (Atlantic); Geyman et al., 2019 (Pacific); Hsieh & Henderson, 2017 (Southern). Nickel: Archer et al., 2020 (Atlantic); Takano et al., 2017 (Pacific); R. M. Wang et al., 2019 (Southern). Chromium: Goring-Harford et al., 2018 (Atlantic); Moos & Boyle, 2019 (Pacific); Rickli et al., 2019 (Southern). Silver: Fischer et al., 2018 (Pacific); Boye et al., 2012 (Southern)Phytoplankton productivity and export sequester climatically significant quantities of atmospheric carbon dioxide as particulate organic carbon through a suite of processes termed the biological pump. Constraining how the biological pump operated in the past is important for understanding past atmospheric carbon dioxide concentrations and Earth's climate history. However, reconstructing the history of the biological pump requires proxies. Due to their intimate association with biological processes, several bioactive trace metals and their isotopes are potential proxies for past phytoplankton productivity, including iron, zinc, copper, cadmium, molybdenum, barium, nickel, chromium, and silver. Here, we review the oceanic distributions, driving processes, and depositional archives for these nine metals and their isotopes based on GEOTRACES-era datasets. We offer an assessment of the overall maturity of each isotope system to serve as a proxy for diagnosing aspects of past ocean productivity and identify priorities for future research. This assessment reveals that cadmium, barium, nickel, and chromium isotopes offer the most promise as tracers of paleoproductivity, whereas iron, zinc, copper, and molybdenum do not. Too little is known about silver to make a confident determination. Intriguingly, the trace metals that are least sensitive to productivity may be used to track other aspects of ocean chemistry, such as nutrient sources, particle scavenging, organic complexation, and ocean redox state. These complementary sensitivities suggest new opportunities for combining perspectives from multiple proxies that will ultimately enable painting a more complete picture of marine paleoproductivity, biogeochemical cycles, and Earth's climate historyThis contribution grew (and grew) out of a joint workshop between GEOTRACES and Past Global Changes (PAGES) held in Aix-en-Provence in December 2018. The workshop was funded by the U.S. National Science Foundation (NSF) through the GEOTRACES program, the international PAGES project, which received support from the Swiss Academy of Sciences and NSF, and the French program Les Envelopes Fluides et l'Environnement. [...] T. J. Horner acknowledges support from NSF; S. H. Little from the UK Natural Environment Research Council (NE/P018181/1); T. M. Conway from the University of South Florida; and, J. R. Farmer from the Max Planck Society, the Tuttle Fund of the Department of Geosciences of Princeton University, the Grand Challenges Program of the Princeton Environmental Institute, and the Andlinger Center for Energy and the Environment of Princeton University. [...] With the institutional support of the âSevero Ochoa Centre of Excellenceâ accreditation (CEX2019-000928-S
Individual variation in hunger, energy intake and ghrelin responses to acute exercise
Purpose This study aimed to characterize the immediate and extended effect of acute exercise on hunger, energy intake, and circulating acylated ghrelin concentrations using a large data set of homogenous experimental trials and to describe the variation in responses between individuals.
Methods Data from 17 of our group's experimental crossover trials were aggregated yielding a total sample of 192 young, healthy males. In these studies, single bouts of moderate to high-intensity aerobic exercise (69% ± 5% VËO2 peak; mean ± SD) were completed with detailed participant assessments occurring during and for several hours postexercise. Mean hunger ratings were determined during (n = 178) and after (n = 118) exercise from visual analog scales completed at 30-min intervals, whereas ad libitum energy intake was measured within the first hour after exercise (n = 60) and at multiple meals (n = 128) during the remainder of trials. Venous concentrations of acylated ghrelin were determined at strategic time points during (n = 118) and after (n = 89) exercise.
Results At group level, exercise transiently suppressed hunger (P < 0.010, Cohen's d = 0.77) but did not affect energy intake. Acylated ghrelin was suppressed during exercise (P < 0.001, Cohen's d = 0.10) and remained significantly lower than control (no exercise) afterward (P < 0.024, Cohen's d = 0.61). Between participants, there were notable differences in responses; however, a large proportion of this spread lay within the boundaries of normal variation associated with biological and technical assessment error.
Conclusion In young men, acute exercise suppresses hunger and circulating acylated ghrelin concentrations with notable diversity between individuals. Care must be taken to distinguish true interindividual variation from random differences within normal limits
Two mini-Neptunes Transiting the Adolescent K-star HIP 113103 Confirmed with TESS and CHEOPS
We report the discovery of two mini-Neptunes in near 2:1 resonance orbits
( d for HIP 113103 b and d for HIP 113103 c) around
the adolescent K-star HIP 113103 (TIC 121490076). The planet system was first
identified from the TESS mission, and was confirmed via additional photometric
and spectroscopic observations, including a 17.5 hour observation for the
transits of both planets using ESA CHEOPS. We place min and
min limits on the absence of transit timing variations over the three year
photometric baseline, allowing further constraints on the orbital
eccentricities of the system beyond that available from the photometric transit
duration alone. With a planetary radius of
, HIP 113103 b resides within the
radius gap, and this might provide invaluable information on the formation
disparities between super-Earths and mini-Neptunes. Given the larger radius
for HIP 113103 c, and close proximity
of both planets to HIP 113103, it is likely that HIP 113103 b might have lost
(or is still losing) its primordial atmosphere. We therefore present simulated
atmospheric transmission spectra of both planets using JWST, HST, and Twinkle.
It demonstrates a potential metallicity difference (due to differences in their
evolution) would be a challenge to detect if the atmospheres are in chemical
equilibrium. As one of the brightest multi sub-Neptune planet systems suitable
for atmosphere follow up, HIP 113103 b and HIP 113103 c could provide insight
on planetary evolution for the sub-Neptune K-star population.Comment: 18 pages, 12 figures, accepted for publication in the Monthly Notices
of the Royal Astronomical Societ
How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRRâs Rehabilitation Engineering Research Centers
Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a âtotal approach to rehabilitationâ, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970âs, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program
A planet within the debris disk around the pre-main-sequence star AU Microscopii
AU Microscopii (AU Mic) is the second closest pre main sequence star, at a
distance of 9.79 parsecs and with an age of 22 million years. AU Mic possesses
a relatively rare and spatially resolved3 edge-on debris disk extending from
about 35 to 210 astronomical units from the star, and with clumps exhibiting
non-Keplerian motion. Detection of newly formed planets around such a star is
challenged by the presence of spots, plage, flares and other manifestations of
magnetic activity on the star. Here we report observations of a planet
transiting AU Mic. The transiting planet, AU Mic b, has an orbital period of
8.46 days, an orbital distance of 0.07 astronomical units, a radius of 0.4
Jupiter radii, and a mass of less than 0.18 Jupiter masses at 3 sigma
confidence. Our observations of a planet co-existing with a debris disk offer
the opportunity to test the predictions of current models of planet formation
and evolution.Comment: Nature, published June 24th [author spelling name fix
- âŠ