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Imbalanced land-surface water budgets in a numerical weather prediction system
There has been a significant increase in the skill and resolution of numerical weather prediction models (NWPs) in recent decades, extending the time scales of useful weather predictions. The land-surface models (LSMs) of NWPs are often employed in hydrological applications, which raises the question of how hydrologically representative LSMs really are. In this paper, precipitation (P), evaporation (E) and runoff (R) from the European Centre for Medium-Range Weather Forecasts (ECMWF) global models were evaluated against observational products. The forecasts differ substantially from observed data for key hydrological variables. In addition, imbalanced surface water budgets, mostly caused by data assimilation, were found on both global (P-E) and basin scales (P-E-R), with the latter being more important. Modeled surface fluxes should be used with care in hydrological applications and further improvement in LSMs in terms of process descriptions, resolution and estimation of uncertainties is needed to accurately describe the land-surface water budgets
Context-Aware Sensing and Implicit Ground Truth Collection: Building a Foundation for Event Triggered Surveys on Autonomous Shuttles: Artikel
The LINC project aims to study interactions between passengers and autonomous vehicles in natural settings at the campus of Technical University of Denmark. To leverage the potential of IoT components in smartphone-based surveying, a system to identify specific spatial, temporal and occupancy contexts relevant for passengersâ experience was proposed as a central data collection strategy in the LINC project. Based on predefined contextual triggers specific questionnaires can be distributed to affected passengers. This work focuses on the data-based discrimination between two fundamental contexts for LINC passengers: be-in and be-out (BIBO) of the vehicle. We present empirical evidence that Bluetooth-low-energy beacons (BLE) have the potential for BIBO independent classification. We compare BLE with other smartphone onboard sensors, such as the global positioning system (GPS) and the accelerometer through: (i) random-forest (RF); (ii) multi-layer perceptron (MLP); and (iii) smartphone native off-the-shelve classifiers. We also perform a sensitivity analysis regarding the impact that faulty BIBO ground-truth has on the performance of the supervised classifiers (i) and (ii). Results show that BLE and GPS could allow reciprocal validation for BIBO passengersâ status. This potential might lift passengers from providing any further validation. We describe the smartphone-sensing platform deployed to gather the dataset used in this work, which involves passengers and autonomous vehicles in a realistic setting
Adherence to the Nordic Nutrition Recommendations in a Nordic population with metabolic syndrome: high salt consumption and low dietary fibre intake (The SYSDIET study).
To access publisher's full text version of this article. Please click on the hyperlink in Additional Links field.The Nordic countries collaborate in setting recommendations for intake of nutrients by publishing the Nordic Nutrition Recommendations (NNR). Studies exploring how well the Nordic population adheres to the NNR are limited and none are available for the metabolic syndrome (MetS) subgroup. Individuals with MetS are a large part of the adult Nordic population and their diet's nutritional quality is of great importance as it can affect the progression of MetS.To evaluate nutritional intake in a cohort of Nordic adults with MetS or MetS risk factors and their adherence to the NNR.A multi-centre study was carried out in six centres in four Nordic countries (SYSDIET CoE). Participants (n=175) were 30-65 years of age, with BMI 27-38 kg/m(2) and had at least two criteria for MetS. The NNR was used to evaluate the baseline nutrient intake calculated from the participants' 4-day food diaries using national nutrient databases.Less than 20% of participants consumed â€10 E% from saturated fat as recommended in the NNR. Recommended intake (RI) of polyunsaturated fat was met by approximately one-third of participants. Only 20% of men and 26% of women met the RI of dietary fibre. Intake below the defined lower intake level of 2.5 ”g/day for vitamin D was observed in nearly 20% of participants. The daily median intake of salt was 8.8 g for men and 6.7 g for women.Dietary quality of this Nordic population with Mets or MetS risk factors is unsatisfactory and characterised by high intakes of SFA and sodium and low intakes of PUFA and dietary fibre. Vitamin D intake was below RI level in a large part of the population. Authorities in the Nordic countries are encouraged to develop intervention programmes for high-risk groups.Academy of Finland
Finnish Diabetes Research Foundation
Sigrid Juselius Foundation
Kuopio University Hospital (Finland)
Druvan Foundation
ESPEN
Skane County Council Research and Development Foundation
Swedish Council for Working Life and Social Research
Heart-Lung Foundation
Diabetesfonden and Foundation Cerealia (Sweden)
Danish Obesity Research Centre (DanORC)
Danish Council for Strategic Research (DairyHealth, BioFunCarb) (Denmark)
Agricultural Productivity Fund (Iceland)
NordFors
Seamless cross-scale modeling with SCHISM
We present a new 3D unstructured-grid model (SCHISM) which is an upgrade from an existing model (SELFE). The new advection scheme for the momentum equation includes an iterative smoother to reduce excess mass produced by higher-order kriging method, and a new viscosity formulation is shown to work robustly for generic unstructured grids and effectively filter out spurious modes without introducing excessive dissipation. A new higher-order implicit advection scheme for transport (TVD2) is proposed to effectively handle a wide range of Courant numbers as commonly found in typical cross-scale applications. The addition of quadrangular elements into the model, together with a recently proposed, highly flexible vertical grid system (Zhang et al., A new vertical coordinate system for a 3D unstructured-grid model. Ocean Model. 85, 2015), leads to model polymorphism that unifies 1D/2DH/2DV/3D cells in a single model grid. Results from several test cases demonstrate the model\u27s good performance in the eddying regime, which presents greater challenges for unstructured-grid models and represents the last missing link for our cross-scale model. The model can thus be used to simulate cross-scale processes in a seamless fashion (i.e. from deep ocean into shallow depths). Published by Elsevier Ltd
TOI-733 b -- a planet in the small-planet radius valley orbiting a Sun-like star
We report the discovery of a hot ( 1055 K) planet in
the small planet radius valley transiting the Sun-like star TOI-733, as part of
the KESPRINT follow-up program of TESS planets carried out with the HARPS
spectrograph. TESS photometry from sectors 9 and 36 yields an orbital period of
= days and a radius of
= .
Multi-dimensional Gaussian process modelling of the radial velocity
measurements from HARPS and activity indicators, gives a semi-amplitude of
= m s, translating into a planet mass of
= . These
parameters imply that the planet is of moderate density ( =
g cm) and place it in the transition
region between rocky and volatile-rich planets with H/He-dominated envelopes on
the mass-radius diagram. Combining these with stellar parameters and
abundances, we calculate planet interior and atmosphere models, which in turn
suggest that TOI-733 b has a volatile-enriched, most likely secondary outer
envelope, and may represent a highly irradiated ocean world - one of only a few
such planets around G-type stars that are well-characterised.Comment: Accepted for publication in A&
Qualitative analysis of how patients decide that they want risk-reducing mastectomy, and the implications for surgeons in responding to emotionally-motivated patient requests
Objective
Contemporary approaches to medical decision-making advise that clinicians should respect patientsâ decisions. However, patientsâ decisions are often shaped by heuristics, such as being guided by emotion, rather than by objective risk and benefit. Risk-reducing mastectomy (RRM) decisions focus this dilemma sharply. RRM reduces breast cancer (BC) risk, but is invasive and can have iatrogenic consequences. Previous evidence suggests that emotion guides patientsâ decision-making about RRM. We interviewed patients to better understand how they made decisions about RRM, using findings to consider how clinicians could ethically respond to their decisions.
Methods
Qualitative face-to-face interviews with 34 patients listed for RRM surgery and two who had decided against RRM.
Results
Patients generally did not use objective risk estimates or, indeed, consider risks and benefits of RRM. Instead emotions guided their decisions: they chose RRM because they feared BC and wanted to do âall they couldâ to prevent it. Most therefore perceived RRM to be the âobviousâ option and made the decision easily. However, many recounted extensive post-decisional deliberation, generally directed towards justifying the original decision. A few patients deliberated before the decision because fears of surgery counterbalanced those of BC.
Conclusion
Patients seeking RRM were motivated by fear of BC, and the need to avoid potential regret for not doing all they could to prevent it. We suggest that choices such as that for RRM, which are made emotionally, can be respected as autonomous decisions, provided patients have considered risks and benefits. Drawing on psychological theory about how people do make decisions, as well as normative views of how they should, we propose that practitioners can guide consideration of risks and benefits even, where necessary, after patients have opted for surgery. This model of practice could be extended to other medical decisions that are influenced by patientsâ emotions
A Radial Velocity Study of the Planetary System of pi Mensae: Improved Planet Parameters for pi Mensae c and a Third Planet on a 125 Day Orbit
Ï Men hosts a transiting planet detected by the Transiting Exoplanet Survey Satellite space mission and an outer planet in a 5.7 yr orbit discovered by radial velocity (RV) surveys. We studied this system using new RV measurements taken with the HARPS spectrograph on ESO's 3.6 m telescope, as well as archival data. We constrain the stellar RV semiamplitude due to the transiting planet, Ï Men c, as Kc = 1.21 ± 0.12 m s^{â1}, resulting in a planet mass of M_{c} = 3.63 ± 0.38 M_{â}. A planet radius of R_{c} = 2.145 ± 0.015 R_{â} yields a bulk density of Ïc = 2.03 ± 0.22 g cm^{â3}. The precisely determined density of this planet and the brightness of the host star make Ï Men c an excellent laboratory for internal structure and atmospheric characterization studies. Our HARPS RV measurements also reveal compelling evidence for a third body, Ï Men d, with a minimum mass M_{d} sin i_{d} = 13.38 ± 1.35 M_{â} orbiting with a period of Porb,d = 125 days on an eccentric orbit (e_{d} = 0.22). A simple dynamical analysis indicates that the orbit of Ï Men d is stable on timescales of at least 20 Myr. Given the mutual inclination between the outer gaseous giant and the inner rocky planet and the presence of a third body at 125 days, Ï Men is an important planetary system for dynamical and formation studies
Company for the ultra-high density, ultra-short period sub-Earth GJ 367 b: discovery of two additional low-mass planets at 11.5 and 34 days
GJ 367 is a bright (V 10.2) M1 V star that has been recently found
to host a transiting ultra-short period sub-Earth on a 7.7 hr orbit. With the
aim of improving the planetary mass and radius and unveiling the inner
architecture of the system, we performed an intensive radial velocity follow-up
campaign with the HARPS spectrograph -- collecting 371 high-precision
measurements over a baseline of nearly 3 years -- and combined our Doppler
measurements with new TESS observations from sectors 35 and 36. We found that
GJ 367 b has a mass of = 0.633 0.050 M and a
radius of = 0.699 0.024 R, corresponding to
precisions of 8% and 3.4%, respectively. This implies a planetary bulk density
of = 10.2 1.3 g cm, i.e., 85% higher than
Earth's density. We revealed the presence of two additional non transiting
low-mass companions with orbital periods of 11.5 and 34 days and minimum
masses of = 4.13 0.36 M and
= 6.03 0.49 M, respectively,
which lie close to the 3:1 mean motion commensurability. GJ 367 b joins the
small class of high-density planets, namely the class of super-Mercuries, being
the densest ultra-short period small planet known to date. Thanks to our
precise mass and radius estimates, we explored the potential internal
composition and structure of GJ 367 b, and found that it is expected to have an
iron core with a mass fraction of 0.91. How this iron core is
formed and how such a high density is reached is still not clear, and we
discuss the possible pathways of formation of such a small ultra-dense planet.Comment: 28 pages, 11 figures. Accepted for publication in ApJ
A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system
It is commonly accepted that exoplanets with orbital periods shorter than one day, also known as ultra-short-period (USP) planets, formed further out within their natal protoplanetary disks before migrating to their current-day orbits via dynamical interactions. One of the most accepted theories suggests a violent scenario involving high-eccentricity migration followed by tidal circularization. Here we present the discovery of a four-planet system orbiting the bright (V = 10.5) K6 dwarf star TOI-500. The innermost planet is a transiting, Earth-sized USP planet with an orbital period of ~13 hours, a mass of 1.42 ± 0.18 Mâ, a radius of 1.166â0.058+0.061Râ and a mean density of 4.89â0.88+1.03gcmâ3. Via Doppler spectroscopy, we discovered that the system hosts 3 outer planets on nearly circular orbits with periods of 6.6, 26.2 and 61.3 days and minimum masses of 5.03 ± 0.41 Mâ, 33.12 ± 0.88 Mâ and 15.05â1.11+1.12Mâ, respectively. The presence of both a USP planet and a low-mass object on a 6.6-day orbit indicates that the architecture of this system can be explained via a scenario in which the planets started on low-eccentricity orbits then moved inwards through a quasi-static secular migration. Our numerical simulations show that this migration channel can bring TOI-500 b to its current location in 2 Gyr, starting from an initial orbit of 0.02 au. TOI-500 is the first four-planet system known to host a USP Earth analogue whose current architecture can be explained via a non-violent migration scenario
TOI-2196 b : Rare planet in the hot Neptune desert transiting a G-type star
Funding: C.M.P., M.F., I.G., and J.K. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18, 177/19, 2020-00104). L.M.S and D.G. gratefully acknowledge financial support from the CRT foundation under Grant No. 2018.2323 âGaseous or rocky? Unveiling the nature of small worldsâ. P.K. acknowledges support from grant LTT-20015. E.G. acknowledge the support of the ThĂŒringer Ministerium fĂŒr Wirtschaft, Wissenschaft und Digitale Gesellschaft. J.S.J. gratefully acknowledges support by FONDECYT grant 1201371 and from the ANID BASAL projects ACE210002 and FB210003. H.J.D. acknowledges support from the Spanish Research Agency of the Ministry of Science and Innovation (AEI-MICINN) under grant PID2019-107061GBC66, DOI: 10.13039/501100011033. D.D. acknowledges support from the TESS Guest Investigator Program grants 80NSSC21K0108 and 80NSSC22K0185. M.E. acknowledges the support of the DFG priority program SPP 1992 "Exploring the Diversity of Extrasolar Planets" (HA 3279/12-1). K.W.F.L. was supported by Deutsche Forschungsgemeinschaft grants RA714/14-1 within the DFG Schwerpunkt SPP 1992, Exploring the Diversity of Extrasolar Planets. N.N. acknowledges support from JSPS KAKENHI Grant Number JP18H05439, JST CREST Grant Number JPMJCR1761. M.S.I.P. is funded by NSF.The hot Neptune desert is a region hosting a small number of short-period Neptunes in the radius-instellation diagram. Highly irradiated planets are usually either small (R âČ 2 Râ) and rocky or they are gas giants with radii of âł1 RJ. Here, we report on the intermediate-sized planet TOI-2196 b (TIC 372172128.01) on a 1.2 day orbit around a G-type star (V = 12.0, [Fe/H] = 0.14 dex) discovered by the Transiting Exoplanet Survey Satellite in sector 27. We collected 41 radial velocity measurements with the HARPS spectrograph to confirm the planetary nature of the transit signal and to determine the mass. The radius of TOI-2196 b is 3.51 ± 0.15 Râ, which, combined with the mass of 26.0 ± 1.3 Mâ, results in a bulk density of 3.31â0.43+0.51 g cmâ3. Hence, the radius implies that this planet is a sub-Neptune, although the density is twice than that of Neptune. A significant trend in the HARPS radial velocity measurements points to the presence of a distant companion with a lower limit on the period and mass of 220 days and 0.65 MJ, respectively, assuming zero eccentricity. The short period of planet b implies a high equilibrium temperature of 1860 ± 20 K, for zero albedo and isotropic emission. This places the planet in the hot Neptune desert, joining a group of very few planets in this parameter space discovered in recent years. These planets suggest that the hot Neptune desert may be divided in two parts for planets with equilibrium temperatures of âł1800 K: a hot sub-Neptune desert devoid of planets with radii of â 1.8â3 Râ and a sub-Jovian desert for radii of â5â12 Râ. More planets in this parameter space are needed to further investigate this finding. Planetary interior structure models of TOI-2196 b are consistent with a H/He atmosphere mass fraction between 0.4% and 3%, with a mean value of 0.7% on top of a rocky interior. We estimated the amount of mass this planet might have lost at a young age and we find that while the mass loss could have been significant, the planet had not changed in terms of character: it was born as a small volatile-rich planet and it remains one at present.Publisher PDFPeer reviewe
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