37 research outputs found
Design of a Digital-Based, Multicomponent Nutrition Guidance System for Prevention of Early Childhood Obesity
Interventions targeting parenting focused modifiable factors to prevent obesity and promote healthy growth in the first 1000 days of life are needed. Scale-up of interventions to global populations is necessary to reverse trends in weight status among infants and toddlers, and large scale dissemination will require understanding of effective strategies. Utilizing nutrition education theories, this paper describes the design of a digital-based nutrition guidance system targeted to first-time mothers to prevent obesity during the first two years. The multicomponent system consists of scientifically substantiated content, tools, and telephone-based professional support delivered in an anticipatory and sequential manner via the internet, email, and text messages, focusing on educational modules addressing the modifiable factors associated with childhood obesity. Digital delivery formats leverage consumer media trends and provide the opportunity for scale-up, unavailable to previous interventions reliant on resource heavy clinic and home-based counseling. Designed initially for use in the United States, this system’s core features are applicable to all contexts and constitute an approach fostering healthy growth, not just obesity prevention. The multicomponent features, combined with a global concern for optimal growth and positive trends in mobile internet use, represent this system’s future potential to affect change in nutrition practice in developing countries
Deformable mirror-based pupil chopping for exoplanet imaging and adaptive optics
Due to turbulence in the atmosphere images taken from ground-based telescopes
become distorted. With adaptive optics (AO) images can be given greater clarity
allowing for better observations with existing telescopes and are essential for
ground-based coronagraphic exoplanet imaging instruments. A disadvantage to
many AO systems is that they use sensors that can not correct for non-common
path aberrations. We have developed a new focal plane wavefront sensing
technique to address this problem called deformable mirror (DM)-based pupil
chopping. The process involves a coronagraphic or non-coronagraphic science
image and a deformable mirror, which modulates the phase by applying a local
tip/tilt every other frame which enables correcting for leftover aberrations in
the wavefront after a conventional AO correction. We validate this technique
with both simulations (for coronagraphic and non-coronagraphic images) and
testing (for non-coronagraphic images) on UCSC's Santa Cruz Extreme AO
Laboratory (SEAL) testbed. We demonstrate that with as low as 250 nm of DM
stroke to apply the local tip/tilt this wavefront sensor is linear for
low-order Zernike modes and enables real-time control, in principle up to kHz
speeds to correct for residual atmospheric turbulence.Comment: Conference Proceeding for 2023 SPIE Optics & Photonics, Techniques
and Instrumentation for Detection of Exoplanets X
Need for Early Interventions in the Prevention of Pediatric Overweight: A Review and Upcoming Directions
Childhood obesity is currently one of the most prevailing and challenging public health issues among industrialized countries and of international priority. The global prevalence of obesity poses such a serious concern that the World Health Organization (WHO) has described it as a “global epidemic.” Recent literature suggests that the genesis of the problem occurs in the first years of life as feeding patterns, dietary habits, and parental feeding practices are established. Obesity prevention evidence points to specific dietary factors, such as the promotion of breastfeeding and appropriate introduction of nutritious complementary foods, but also calls for attention to parental feeding practices, awareness of appropriate responses to infant hunger and satiety cues, physical activity/inactivity behaviors, infant sleep duration, and family meals. Interventions that begin at birth, targeting multiple factors related to healthy growth, have not been adequately studied. Due to the overwhelming importance and global significance of excess weight within pediatric populations, this narrative review was undertaken to summarize factors associated with overweight and obesity among infants and toddlers, with focus on potentially modifiable risk factors beginning at birth, and to address the need for early intervention prevention
Identifying Exoplanets with Deep Learning. V. Improved Light Curve Classification for TESS Full Frame Image Observations
The TESS mission produces a large amount of time series data, only a small
fraction of which contain detectable exoplanetary transit signals. Deep
learning techniques such as neural networks have proved effective at
differentiating promising astrophysical eclipsing candidates from other
phenomena such as stellar variability and systematic instrumental effects in an
efficient, unbiased and sustainable manner. This paper presents a high quality
dataset containing light curves from the Primary Mission and 1st Extended
Mission full frame images and periodic signals detected via Box Least Squares
(Kov\'acs et al. 2002; Hartman 2012). The dataset was curated using a thorough
manual review process then used to train a neural network called
Astronet-Triage-v2. On our test set, for transiting/eclipsing events we achieve
a 99.6% recall (true positives over all data with positive labels) at a
precision of 75.7% (true positives over all predicted positives). Since 90% of
our training data is from the Primary Mission, we also test our ability to
generalize on held-out 1st Extended Mission data. Here, we find an area under
the precision-recall curve of 0.965, a 4% improvement over Astronet-Triage (Yu
et al. 2019). On the TESS Object of Interest (TOI) Catalog through April 2022,
a shortlist of planets and planet candidates, Astronet-Triage-v2 is able to
recover 3577 out of 4140 TOIs, while Astronet-Triage only recovers 3349 targets
at an equal level of precision. In other words, upgrading to Astronet-Triage-v2
helps save at least 200 planet candidates from being lost. The new model is
currently used for planet candidate triage in the Quick-Look Pipeline (Huang et
al. 2020a,b; Kunimoto et al. 2021).Comment: accepted for publication in AJ. code can be found at:
https://github.com/mdanatg/Astronet-Triage and data can be found at:
https://zenodo.org/record/741157
GDF15 Provides an Endocrine Signal of Nutritional Stress in Mice and Humans.
GDF15 is an established biomarker of cellular stress. The fact that it signals via a specific hindbrain receptor, GFRAL, and that mice lacking GDF15 manifest diet-induced obesity suggest that GDF15 may play a physiological role in energy balance. We performed experiments in humans, mice, and cells to determine if and how nutritional perturbations modify GDF15 expression. Circulating GDF15 levels manifest very modest changes in response to moderate caloric surpluses or deficits in mice or humans, differentiating it from classical intestinally derived satiety hormones and leptin. However, GDF15 levels do increase following sustained high-fat feeding or dietary amino acid imbalance in mice. We demonstrate that GDF15 expression is regulated by the integrated stress response and is induced in selected tissues in mice in these settings. Finally, we show that pharmacological GDF15 administration to mice can trigger conditioned taste aversion, suggesting that GDF15 may induce an aversive response to nutritional stress.This work and authors were funded by the NIHR Cambridge Biomedical Research Centre; NIHR Rare Disease Translational Research Collaboration; Medical Research Council [MC_UU_12012/2 and MRC_MC_UU_12012/3]; MRC Metabolic Diseases Unit [MRC_MC_UU_12012/5 and MRC_MC_UU_12012.1]; Wellcome Trust Strategic Award [100574/Z/12/Z and 100140]; Wellcome Trust [107064 , 095515/Z/11/Z , 098497/Z/12/Z, 106262/Z/14/Z and 106263/Z/14/Z]; British Heart Foundation [RG/12/13/29853]; Addenbrooke’s Charitable Trust / Evelyn Trust Cambridge Clinical Research Fellowship [16-69]
US Department of Agriculture: 2010-34323-21052; EFSD project grant and a Royal College of Surgeons Research Fellowship, Diabetes UK Harry Keen intermediate clinical fellowship (17/0005712). European Research Council, Bernard Wolfe Health Neuroscience Endowment, Experimental Medicine Training Initiative/AstraZeneca and Medimmune
Identifying Exoplanets with Deep Learning. III. Automated Triage and Vetting of TESS Candidates
NASA’s Transiting Exoplanet Survey Satellite (TESS) presents us with an unprecedented volume of space-based photometric observations that must be analyzed in an efficient and unbiased manner. With at least ∼1,000,000 new light curves generated every month from full-frame images alone, automated planet candidate identification has become an attractive alternative to human vetting. Here we present a deep learning model capable of performing triage and vetting on TESS candidates. Our model is modified from an existing neural network designed to automatically classify Kepler candidates, and is the first neural network to be trained and tested on real TESS data. In triage mode, our model can distinguish transit-like signals (planet candidates and eclipsing binaries) from stellar variability and instrumental noise with an average precision (the weighted mean of precisions over all classification thresholds) of 97.0% and an accuracy of 97.4%. In vetting mode, the model is trained to identify only planet candidates with the help of newly added scientific domain knowledge, and achieves an average precision of 69.3% and an accuracy of 97.8%. We apply our model on new data from Sector 6, and present 288 new signals that received the highest scores in triage and vetting and were also identified as planet candidates by human vetters. We also provide a homogeneously classified set of TESS candidates suitable for future training
Changes in Waist Circumference and the Incidence of Acute Myocardial Infarction in Middle-Aged Men and Women
BACKGROUND: Waist circumference (WC) measured at one point in time is positively associated with the risk of acute myocardial infarction (MI), but the association with changes in WC (DWC) is not clear. We investigated the association between DWC and the risk of MI in middle-aged men and women, and evaluated the influence from concurrent changes in BMI (DBMI). METHODOLOGY/PRINCIPAL FINDINGS: Data on 38,593 participants from the Danish Diet, Cancer and Health study was analysed. Anthropometry was assessed in 1993-97 and 1999-02. Information on fatal and non-fatal MI was obtained from National Registers. Cases were validated by review of the medical records. Hazard ratios (HR) were calculated from Cox proportional hazard models with individuals considered at risk from 1999-02 until December 30 2009. During 8.4 years of follow-up, 1,041 incident cases of MI occurred. WC was positively associated with the risk of MI, but weakly after adjustment for BMI. DWC was not associated with the risk of MI (HR per 5 cm change = 1.01 (0.95, 1.09) with adjustment for covariates, baseline WC, BMI and DBMI). Associations with DWC were not notably different in sub-groups stratified according to baseline WC or DBMI, or when individuals with MI occurring within the first years of follow-up were excluded. CONCLUSIONS/SIGNIFICANCE: WC was positively associated with the risk of MI in middle-aged men and women, but changes in WC were not. These findings suggest that a reduction in WC may be an insufficient target for prevention of MI in middle-aged men and women
The TESS-Keck Survey. XVI. Mass Measurements for 12 Planets in Eight Systems
With JWST's successful deployment and unexpectedly high fuel reserves,
measuring the masses of sub-Neptunes transiting bright, nearby stars will soon
become the bottleneck for characterizing the atmospheres of small exoplanets
via transmission spectroscopy. Using a carefully curated target list and more
than two years' worth of APF-Levy and Keck-HIRES Doppler monitoring, the
TESS-Keck Survey is working toward alleviating this pressure. Here we present
mass measurements for 11 transiting planets in eight systems that are
particularly suited to atmospheric follow-up with JWST. We also report the
discovery and confirmation of a temperate super-Jovian-mass planet on a
moderately eccentric orbit. The sample of eight host stars, which includes one
subgiant, spans early-K to late-F spectral types ( 5200--6200
K). We homogeneously derive planet parameters using a joint photometry and
radial velocity modeling framework, discuss the planets' possible bulk
compositions, and comment on their prospects for atmospheric characterization.Comment: Accepted for publication in The Astronomical Journal on 2023-Jun-22.
60 pages, 17 Tables, 28 Figure