14 research outputs found
TOI-3785 b: A Low-Density Neptune Orbiting an M2-Dwarf Star
Using both ground-based transit photometry and high-precision radial velocity
(RV) spectroscopy, we confirm the planetary nature of TOI-3785 b. This
transiting Neptune orbits an M2-Dwarf star with a period of ~4.67 days, a
planetary radius of 5.14 +/- 0.16 Earth Radii, a mass of 14.95 +4.10, -3.92
Earth Masses, and a density of 0.61 +0.18, -0.17 g/cm^3. TOI-3785 b belongs to
a rare population of Neptunes (4 Earth Radii < Rp < 7 Earth Radii) orbiting
cooler, smaller M-dwarf host stars, of which only ~10 have been confirmed. By
increasing the number of confirmed planets, TOI-3785 b offers an opportunity to
compare similar planets across varying planetary and stellar parameter spaces.
Moreover, with a high transmission spectroscopy metric (TSM) of ~150 combined
with a relatively cool equilibrium temperature of 582 +/- 16 K and an inactive
host star, TOI-3785 b is one of the more promising low-density M-dwarf Neptune
targets for atmospheric follow-up. Future investigation into atmospheric mass
loss rates of TOI-3785 b may yield new insights into the atmospheric evolution
of these low-mass gas planets around M-dwarfs.Comment: 22 pages, 6 figures, 6 tables, Submitted to A
TOI-2015b: A Warm Neptune with Transit Timing Variations Orbiting an Active mid M Dwarf
We report the discovery of a close-in () warm Neptune with clear transit timing variations (TTVs)
orbiting the nearby () active M4 star, TOI-2015. We
characterize the planet's properties using TESS photometry, precise
near-infrared radial velocities (RV) with the Habitable-zone Planet Finder (HP)
Spectrograph, ground-based photometry, and high-contrast imaging. A joint
photometry and RV fit yields a radius , mass , and
density for TOI-2015b,
suggesting a likely volatile-rich planet. The young, active host star has a
rotation period of and
associated rotation-based age estimate of . Though
no other transiting planets are seen in the TESS data, the system shows clear
TTVs of super period and
amplitude . After considering multiple likely
period ratio models, we show an outer planet candidate near a 2:1 resonance can
explain the observed TTVs while offering a dynamically stable solution.
However, other possible two-planet solutions -- including 3:2 and 4:3 resonance
-- cannot be conclusively excluded without further observations. Assuming a 2:1
resonance in the joint TTV-RV modeling suggests a mass of
for TOI-2015b and
for the outer candidate.
Additional transit and RV observations will be beneficial to explicitly
identify the resonance and further characterize the properties of the system.Comment: 28 pages, 15 figures, 6 tables. As submitted to AAS Journal
TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems
We confirm the planetary nature of two gas giants discovered by TESS to
transit M dwarfs with stellar companions at wide separations. TOI-3984 A
() is an M4 dwarf hosting a short-period (
days) gas giant ( and
) with a wide separation white dwarf companion.
TOI-5293 A () is an M3 dwarf hosting a short-period ( days) gas giant ( and
) with a wide separation M dwarf companion. We
characterize both systems using a combination of ground-based and space-based
photometry, speckle imaging, and high-precision radial velocities from the
Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b
( K and ) and TOI-5293 A b
( K and ) are two of the coolest
gas giants among the population of hot Jupiter-sized gas planets orbiting M
dwarfs and are favorable targets for atmospheric characterization of temperate
gas giants and three-dimensional obliquity measurements to probe system
architecture and migration scenarios.Comment: Submitted to AJ, 42 pages, 14 figures. arXiv admin note: substantial
text overlap with arXiv:2201.0996
An integrated environmental and fairtrade labelling scheme for product supply chains
Environmental initiatives such as carbon labelling have been suggested as a driver for achieving sustainable production systems of product supply chains. The paper therefore presents a systematic process of developing an environmental labelling framework as an extension of carbon labelling using the fairtrade certification as a platform to facilitate the process. Using the general theoretical constructs of lifecycle assessments, the framework presented provides insight
into the formulation of multi-regional supply chains which has been specifically characterised in this paper for the UK-India-Rest of the World supply chain. The environmental labelling process presented in this paper is based on two key principles; Quantitative Principle in Eco-labelling and the Principle of Whole Lifecycle Perspective and it is used to inform two key stakeholder groups in the supply chain: consumers and supply chain partners. For consumers, a consistent way of presenting the environmental label information is presented
highlighting the supply chain impacts across the indicators of CO2-eq emissions, water consumption and land use in addition to regional contributions to these impacts from a global
supply chain perspective. Additionally, communicating the environmental impacts to supply chain partners provides a decision support to take actions to reduce the overall impacts by identifying processes within the global supply chain that needed prioritization. Given that fairtrade partnership is based on participatory development and a strict guidelines and
standardization process, it is envisaged that synergies can be derived by integrating environmental labelling with the fairtrade scheme to enhance the environmental sustainability of
product supply chains
A Warm Neptune Orbiting the Nearby Active mid M dwarf TOI-2015 and Precision Spectral Parameters in the Near-Infrared with HPF-SpecMatch
We report on the discovery and characterization of a warm Neptune orbiting the nearby (d=47.3pc) mid M dwarf TOI-2015. We characterize the properties of the planet using TESS photometry, precision near-infrared RVs with the Habitable-zone Planet Finder (HPF) Spectrograph, precision diffuser-assisted ground-based photometry, and high contrast imaging. Using the HPF-SpecMatch spectral matching code, the star has an effective temperature of 3193K. The planet has a radius of R=3.37+/-.20 stellar radii and a mass of M = 12.0 +/- 5.2 stellar masses and we find that its bulk density is compatible with a ~6% H/He gaseous envelope enveloping a rocky core. The star is rapidly rotating with a rotation period of Prot = 6.0 +/- 0.6 days, making the planet one of few M dwarf planets amenable for obliquity constraints via the Rossiter-McLaughlin effect. Due to the large transit depth and the relative brightness of the star at near-infrared wavelengths (J=11.3), the planet is a promising target for atmospheric characterization in the future with JWST. We publicly release a code we call HPF-SpecMatch to calculate accurate stellar parameters from as-observed near-infrared HPF spectra of 170 stars and describe its performance
Social networking and understanding alcohol-associated risk for people with type 1 diabetes: friend or foe?
Background: online communication has become popular in recent years, especially for young people. Limited research exists into how people with type 1 diabetes mellitus (T1DM) discuss risks about diabetes. Alcohol use by people with T1DM, as in the rest of society, is common and may adversely affect diabetes management. This study reviewed the literature on social networking as a communication tool and conducted a systematic search of social networking sites to determine whether people with T1DM use them to discuss risks associated with diabetes and alcohol consumption.Materials and methods: systematic literature review was performed followed by an Internet search and forum identification relating to T1DM and alcohol. Qualitative coding and thematic analysis of publicly available data retrieved from social networking sites were undertaken.Results: in the literature review, 292 articles were identified, of which six met the inclusion criteria. Widespread use of social media for medical advice pertaining to diabetes was reported. The quality and safety of online advice were reported as variable. Ten Web sites with 247 individual postings about alcohol and diabetes were selected for analysis, which revealed six themes ranging from safety and seeking and provision of advice to wider views about behaviors, opinions, and experiences of people with T1DM and alcohol. No specific professional health information was identified on any sites, and inaccurate information was common.Conclusions: online resources are used by people with T1DM to find information about diabetes and alcohol consumption. Easily signposted and accessible professional online resources would ensure people can access appropriate advice to minimize risks of alcohol us
Trajectory of post-traumatic stress and depression among children and adolescents following single-incident trauma.
OBJECTIVE: Post-traumatic stress disorder and depression have high comorbidity. Understanding their relationship is of clinical and theoretical importance. A comprehensive way to understand post-trauma psychopathology is through symptom trajectories. This study aims to look at the developmental courses of PTSD and depression symptoms and their interrelationship in the initial months post-trauma in children and adolescents. METHODS: Two-hundred-and-seventeen children and adolescents aged between eight and 17 exposed to single-event trauma were included in the study. Post-traumatic stress symptoms (PTSS) and depression symptoms were measured at 2Â weeks, 2Â months and 9Â months, with further psychological variables measured at the 2-week assessment. Group-based trajectory modelling (GBTM) was applied to estimate the latent developmental clusters of the two outcomes. Logistic regression was used to identify predictors associated with high symptom groups. RESULTS: The GBTM yielded a three-group model for PTSS and a three-group model for depression. PTSS trajectories showed symptoms reduced to a non-clinical level by 9Â months for all participants (if they were not already in the non-clinical range): participants were observed to be resilient (42.4%) or recovered within 2Â months (35.6%), while 21.9% experienced high level PTSS but recovered by 9Â months post-trauma. The depression symptom trajectories predicted a chronic non-recovery group (20.1%) and two mild symptom groups (45.9%, 34.0%). Further analysis showed high synchronicity between PTSS and depression groups. Peri-event panic, negative appraisals, rumination and thought suppression at 2Â weeks predicted slow recovery from PTSS. Pre-trauma wellbeing, post-trauma anxiety and negative appraisals predicted chronic depression. CONCLUSIONS: Post-trauma depression was more persistent than PTSS at 9Â months in the sampled population. Cognitive appraisal was the shared risk factor to high symptom groups of both PTSS and depression
TOI-3984 A b and TOI-5293 A b: Two Temperate Gas Giants Transiting Mid-M Dwarfs in Wide Binary Systems
We confirm the planetary nature of two gas giants discovered by TESS to transit M dwarfs with stellar companions at wide separations. TOI-3984 A (J = 11.93) is an M4 dwarf hosting a short-period (4.353326 ± 0.000005 days) gas giant (M p = 0.14 ± 0.03 M J and R p = 0.71 ± 0.02 R J) with a wide-separation white dwarf companion. TOI-5293 A (J = 12.47) is an M3 dwarf hosting a short-period (2.930289 ± 0.000004 days) gas giant (M p = 0.54 ± 0.07 M J and R p = 1.06 ± 0.04 R J) with a wide-separation M dwarf companion. We characterize both systems using a combination of ground- and space-based photometry, speckle imaging, and high-precision radial velocities from the Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b (T eq = 563 ± 15 K and TSM = 138 â 27 + 29 ) and TOI-5293 A b ( T eq = 675 â 30 + 42 K and TSM = 92 ± 14) are two of the coolest gas giants among the population of hot Jupiter-sized gas planets orbiting M dwarfs and are favorable targets for atmospheric characterization of temperate gas giants and 3D obliquity measurements to probe system architecture and migration scenarios.ISSN:0004-6256ISSN:1538-388