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1.
Science ; 384(6692): 214-217, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38603482

RESUMO

Massive stars (those ≥8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7% of massive stars have observed magnetic fields, the origin of which is debated. We used multi-epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than its companion. The system properties and a surrounding bipolar nebula can be reproduced with a model in which two stars merged (in a previous triple system) to produce the magnetic massive star. Our results provide observational evidence that magnetic fields form in at least some massive stars through stellar mergers.

2.
Sci Total Environ ; 864: 160978, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563753

RESUMO

Water quality related to non-point source pollution continues to pose challenges in agricultural landscapes, despite two completed cycles of Water Framework Directive actions by farmers and landowners. Future climate projections will cause new challenges in landscape hydrology and subsequently, the potential responses in water quality. Investigating the nutrient trends in surface waters and studying the efficiency of mitigation measures revealed that loads and measures are highly variable both spatially and temporally in catchments with different agro-climatic and environmental conditions. In Sweden, nitrogen and phosphorus loads in eight agricultural catchments (470-3300 ha) have been intensively monitored for >20 years. This study investigated the relationship between precipitation, air temperature, and discharge patterns in relation to nitrogen (N) and phosphorus (P) loads at catchment outlets. The time series data analysis was carried out by integrating Mann-Kendall test, Pettitt break-points, and Generalized Additive Model. The results showed that the nutrient loads highly depend on water discharge, which had large variation in annual average (158-441 mm yr-1). The annual average loads were also considerably different among the catchments with total N (TN) loads ranging from 6.76 to 35.73 kg ha-1, and total P (TP) loads ranging from 0.11 to 1.04 kg ha-1. The climatic drivers were highly significant indicators of nutrient loads but with varying degree of significance. Precipitation (28-962 mm yr-1) was a significant indicator of TN loads in five catchments (loamy sand/sandy loam) while annual average temperature (6.5-8.7 °C yr-1) was a significant driver of TN loads in six out of eight catchments. TP loads were associated with precipitation in two catchments and significantly correlated to water discharge in six catchments. Considering the more frequent occurrence of extreme weather events, it is necessary to tailor N and P mitigation measures to future climate-change features of precipitation, temperature, and discharge.

4.
Phys Rev Lett ; 122(5): 051102, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30822017

RESUMO

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5} erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52} erg. A hypothetical population of transient sources has to be more common than 10^{-5} Mpc^{-3} yr^{-1} (5×10^{-8} Mpc^{-3} yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

5.
Phys Rev Lett ; 120(7): 071801, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29542976

RESUMO

We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ∼5 GeV. That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L/E_{ν} as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δm_{32}^{2}=2.31_{-0.13}^{+0.11}×10^{-3} eV^{2} and sin^{2}θ_{23}=0.51_{-0.09}^{+0.07}, assuming normal neutrino mass ordering. These results are consistent with, and of similar precision to, those from accelerator- and reactor-based experiments.

6.
Public Health ; 158: 47-54, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29547759

RESUMO

OBJECTIVE: ST-segment elevation myocardial infarction (STEMI) has an important economic burden that poised the urgent need to evaluate its catastrophic medical expense. This study evaluates the first 5 years of the national health initiative called Popular Insurance (PI) at the National Institute of Cardiology in Mexico. STUDY DESIGN: Retrospective data analysis. METHODS: STEMI patients with (n=317) and without (n=260) PI were selected. Analysed variables included socio-economical context, management care, cost evaluation and three outcomes (mortality, hospital readmission and therapeutic adherence). Descriptive statistical analyses, Kaplan-Meier survival and Support Vector Machine models were used accordingly. RESULTS: Treatment costs were higher for PI-covered individuals (P=0.022) and only 1.89% of them remained in debt, in contrast to 16.15% of those without PI. Statistically significant differences were found in relation to days in hospital wards (P<0.001), imaging studies (P<0.001) and surgical materials (P=0.04). Survival analysis (P=0.44) and therapeutic adherence (P=0.38) showed no differences. Hospital readmission was predicted with an 81.97% accuracy. The most important predictive variables included were stent type, number of days at the coronary care unit and hospital wards. CONCLUSIONS: The PI has proven to be a successful program where no differences were found in terms of health care and survival, whereas it provides timely financial support for families facing catastrophic health challenging events.


Assuntos
Doença Catastrófica/economia , Gastos em Saúde/estatística & dados numéricos , Infarto do Miocárdio/economia , Programas Nacionais de Saúde , Doença Catastrófica/terapia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos
7.
Eur Phys J C Part Fields ; 78(10): 831, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30930683

RESUMO

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino 'track' events from the Northern Hemisphere, while the second analysis uses 2 years of 'cascade' events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than 10 28 s at 90% CL for dark matter masses above 10 TeV .

9.
Artigo em Inglês | MEDLINE | ID: mdl-28098785

RESUMO

Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire (n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities.


Assuntos
Planejamento Ambiental , Exercício Físico/psicologia , Características de Residência , Caminhada/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arizona , Cidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Suburbana , Inquéritos e Questionários , População Urbana
10.
J Environ Manage ; 195(Pt 1): 70-77, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27939775

RESUMO

We evaluated the potential of an outranking Multi-Criteria Decision Analysis approach for assisting in the participatory assessment of dryland management actions implemented in the San Simon watershed, in southeastern Arizona, USA. We compared an outranking-facilitated assessment of actions with a simple and direct (baseline) ranking of the same actions by the participating stakeholders in terms of: 1) internal homogeneity of each assessment approach, (2) similarity of individual assessments between methods, and (3) effects of the use of implicit/explicit assessment criteria. The actions assessed combined various management approaches, including livestock management (rotation, resting), vegetation management (grass seeding, brush control), and hydraulic structures (dams, dykes). The outranking-facilitated assessment discriminated better between actions and reduced the variability of results between individual stakeholders as compared with the direct ranking of actions. In general, the two assessments significantly differed in the relative preference of the five management actions assessed, yet both assessments identified rotational grazing combined with vegetation management (grass seeding and brush control) as the most preferred management action in the study area. The comparative analysis revealed inconsistencies between the use of implicit and explicit assessment criteria. Our findings highlight the opportunities offered by outranking approaches to help capture, structure, and make explicit stakeholder perspectives in the framework of a participatory environmental assessment process, which may facilitate the understanding of the multiple preferences involved. The outranking integration process, which resembles a voting procedure, proved simple and transparent, with potential for contributing to stakeholder engagement and trust in participatory assessment.


Assuntos
Técnicas de Apoio para a Decisão , Arizona , Conservação dos Recursos Naturais
11.
J Environ Manage ; 195(Pt 1): 35-45, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27939811

RESUMO

The adoption of sustainable land management strategies and practices that respond to current climate and human pressures requires both assessment tools that can lead to better informed decision-making and effective knowledge-exchange mechanisms that facilitate new learning and behavior change. We propose a learning-centered participatory approach that links land management assessment and knowledge exchange and integrates science-based data and stakeholder perspectives on both biophysical and socio-economic attributes. We outline a structured procedure for a transparent assessment of land management alternatives, tailored to dryland management, that is based on (1) principles of constructivism and social learning, (2) the participation of stakeholders throughout the whole assessment process, from design to implementation, and (3) the combination of site-specific indicators, identified by local stakeholders as relevant to their particular objectives and context conditions, and science-based indicators that represent ecosystem services of drylands worldwide. The proposed procedure follows a pattern of eliciting, challenging, and self-reviewing stakeholder perspectives that aims to facilitate learning. The difference between the initial baseline perspectives and the final self-reviewed stakeholder perspectives is used as a proxy of learning. We illustrate the potential of this methodology by its application to the assessment of land uses in a Mediterranean fire-prone area in East Spain. The approach may be applied to a variety of socio-ecological systems and decision-making and governance scales.


Assuntos
Conservação dos Recursos Naturais , Conhecimento , Tomada de Decisões , Ecossistema , Humanos , Aprendizagem
12.
Mol Psychiatry ; 21(11): 1573-1588, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27698428

RESUMO

Human neural progenitors derived from pluripotent stem cells develop into electrophysiologically active neurons at heterogeneous rates, which can confound disease-relevant discoveries in neurology and psychiatry. By combining patch clamping, morphological and transcriptome analysis on single-human neurons in vitro, we defined a continuum of poor to highly functional electrophysiological states of differentiated neurons. The strong correlations between action potentials, synaptic activity, dendritic complexity and gene expression highlight the importance of methods for isolating functionally comparable neurons for in vitro investigations of brain disorders. Although whole-cell electrophysiology is the gold standard for functional evaluation, it often lacks the scalability required for disease modeling studies. Here, we demonstrate a multimodal machine-learning strategy to identify new molecular features that predict the physiological states of single neurons, independently of the time spent in vitro. As further proof of concept, we selected one of the potential neurophysiological biomarkers identified in this study-GDAP1L1-to isolate highly functional live human neurons in vitro.


Assuntos
Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Potenciais de Ação/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Eletrofisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Aprendizado de Máquina , Neurônios/metabolismo , Técnicas de Patch-Clamp , Células-Tronco Pluripotentes , RNA
13.
Lupus ; 25(1): 61-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26306740

RESUMO

OBJECTIVE: The objective of this paper is to assess whether pulmonary hypertension (PH) may be detected at one point in time or longitudinally predicted by serum uric acid (sUA) levels in systemic lupus erythematosus (SLE). METHODS: We conducted a post-hoc analysis of a long-term followed cohort of Mexican SLE patients. Echocardiography-based definitions of PH by the ESC/ERS/ISHLT and its associations with clinical and laboratory data on enrollment were studied. Especially, the impact that sUA levels at baseline may have on the future development of PH in patients with normal pulmonary artery systolic pressure (PASP) was explored. RESULTS: Out of the 156 SLE patients originally enrolled in the cohort, 44 met the inclusion criteria for the present study and were grouped as having (n =10) or not having (n = 34) PH. At baseline, sUA levels of 5.83 ± 1.79 and 5.82 ± 1.97 mg/dl (p = ns) were found in patients with and without PH, respectively. No association between PASP and other markers was found. In patients with normal PASP, the presence of sUA ≥ 7 mg/dl at baseline predicted future development of PH (relative risk 8.5, 1.0009 to 72; p = 0.04). CONCLUSION: In SLE, sUA levels at one point in time are useless to detect PH. However, steady hyperuricemia may predict the future development of PH in patients with normal PASP at baseline.


Assuntos
Hipertensão Pulmonar/etiologia , Hiperuricemia/complicações , Lúpus Eritematoso Sistêmico/complicações , Ácido Úrico/sangue , Adulto , Pressão Arterial , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , México , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/fisiopatologia , Fatores de Risco , Fatores de Tempo , Ultrassonografia
14.
BMJ Open ; 5(8): e007957, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-26310399

RESUMO

OBJECTIVES: Medical journals in Japan generally have appropriate policies regarding disclosure of conflicts of interest (COI). However, COI management depends on the staff members of each journal's editorial secretariat. This study's objectives were to find out (A) whether COI disclosure and the journal's role in it are clearly understood by the journal's secretariat staff, (B) how much experience the editorial secretariat has in actually handling issues related to disclosure and (C) what kind of help or support they need. SETTING AND DESIGN: In January 2014, questionnaires were sent to the editorial secretariats of journal-publishing societies belonging to the Japanese Association of Medical Sciences (JAMS). PARTICIPANTS: The response rate was 100%, and the respondents represented 121 journals published by the 118 JAMS member societies (at the time of the survey). PRIMARY AND SECONDARY OUTCOME MEASURES: Information was collected on the history of COI policies and on how those policies were implemented. At the end of the questionnaire, there was an open-ended call for comments. RESULTS: Compulsory COI disclosure began between 2010 and 2013 for 60.3% of the journals (73/121). Handling of COI issues was not uniform: 17.4% (21/121) of respondents do not pursue cases of dubious disclosure, and 47.9% (58/121) do not require COI disclosures from editorial board members. Very few of the editorial secretariats had clearly-stated consequences for violations of COI-disclosure policy (33/121, 27.3%), and only 28.9% offered COI education (35/121). Respondents' comments indicated that uniform, easily-searchable guidance regarding COI policies and implementation would be welcome. CONCLUSIONS: Although commitment is widespread, policy implementation is inconsistent and COI experience is lacking. Clear, easy-to-use guidelines are desired by many societies. The JAMS is to be commended for supporting this country-wide investigation; other countries and regions are encouraged to perform similar investigations to respond to needs regarding COI management.


Assuntos
Conflito de Interesses , Revelação , Políticas Editoriais , Publicações Periódicas como Assunto/ética , Humanos , Japão , Sociedades Médicas/ética , Inquéritos e Questionários
15.
Nutr Res Pract ; 9(2): 207-12, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25861429

RESUMO

BACKGROUND/OBJECTIVES: The Recaller app was developed to help individuals record their food intakes. This pilot study evaluated the usability of this new food picture application (app), which operates on a smartphone with an embedded camera and Internet capability. SUBJECTS/METHODS: Adults aged 19 to 28 years (23 males and 22 females) were assigned to use the Recaller app on six designated, nonconsecutive days in order to capture an image of each meal and snack before and after eating. The images were automatically time-stamped and uploaded by the app to the Recaller website. A trained nutritionist administered a 24-hour dietary recall interview 1 day after food images were taken. Participants' opinions of the Recaller app and its usability were determined by a follow-up survey. As an evaluation indicator of usability, the number of images taken was analyzed and multivariate Poisson regression used to model the factors determining the number of images sent. RESULTS: A total of 3,315 food images were uploaded throughout the study period. The median number of images taken per day was nine for males and 13 for females. The survey showed that the Recaller app was easy to use, and 50% of the participants would consider using the app daily. Predictors of a higher number of images were as follows: greater interval (hours) between the first and last food images sent, weekend, and female. CONCLUSIONS: The results of this pilot study provide valuable information for understanding the usability of the Recaller smartphone food picture app as well as other similarly designed apps. This study provides a model for assisting nutrition educators in their collection of food intake information by using tools available on smartphones. This innovative approach has the potential to improve recall of foods eaten and monitoring of dietary intake in nutritional studies.

17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-143296

RESUMO

BACKGROUND/OBJECTIVES: The Recaller app was developed to help individuals record their food intakes. This pilot study evaluated the usability of this new food picture application (app), which operates on a smartphone with an embedded camera and Internet capability. SUBJECTS/METHODS: Adults aged 19 to 28 years (23 males and 22 females) were assigned to use the Recaller app on six designated, nonconsecutive days in order to capture an image of each meal and snack before and after eating. The images were automatically time-stamped and uploaded by the app to the Recaller website. A trained nutritionist administered a 24-hour dietary recall interview 1 day after food images were taken. Participants' opinions of the Recaller app and its usability were determined by a follow-up survey. As an evaluation indicator of usability, the number of images taken was analyzed and multivariate Poisson regression used to model the factors determining the number of images sent. RESULTS: A total of 3,315 food images were uploaded throughout the study period. The median number of images taken per day was nine for males and 13 for females. The survey showed that the Recaller app was easy to use, and 50% of the participants would consider using the app daily. Predictors of a higher number of images were as follows: greater interval (hours) between the first and last food images sent, weekend, and female. CONCLUSIONS: The results of this pilot study provide valuable information for understanding the usability of the Recaller smartphone food picture app as well as other similarly designed apps. This study provides a model for assisting nutrition educators in their collection of food intake information by using tools available on smartphones. This innovative approach has the potential to improve recall of foods eaten and monitoring of dietary intake in nutritional studies.


Assuntos
Adulto , Feminino , Humanos , Masculino , Ingestão de Alimentos , Seguimentos , Internet , Refeições , Nutricionistas , Projetos Piloto , Lanches
18.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-143289

RESUMO

BACKGROUND/OBJECTIVES: The Recaller app was developed to help individuals record their food intakes. This pilot study evaluated the usability of this new food picture application (app), which operates on a smartphone with an embedded camera and Internet capability. SUBJECTS/METHODS: Adults aged 19 to 28 years (23 males and 22 females) were assigned to use the Recaller app on six designated, nonconsecutive days in order to capture an image of each meal and snack before and after eating. The images were automatically time-stamped and uploaded by the app to the Recaller website. A trained nutritionist administered a 24-hour dietary recall interview 1 day after food images were taken. Participants' opinions of the Recaller app and its usability were determined by a follow-up survey. As an evaluation indicator of usability, the number of images taken was analyzed and multivariate Poisson regression used to model the factors determining the number of images sent. RESULTS: A total of 3,315 food images were uploaded throughout the study period. The median number of images taken per day was nine for males and 13 for females. The survey showed that the Recaller app was easy to use, and 50% of the participants would consider using the app daily. Predictors of a higher number of images were as follows: greater interval (hours) between the first and last food images sent, weekend, and female. CONCLUSIONS: The results of this pilot study provide valuable information for understanding the usability of the Recaller smartphone food picture app as well as other similarly designed apps. This study provides a model for assisting nutrition educators in their collection of food intake information by using tools available on smartphones. This innovative approach has the potential to improve recall of foods eaten and monitoring of dietary intake in nutritional studies.


Assuntos
Adulto , Feminino , Humanos , Masculino , Ingestão de Alimentos , Seguimentos , Internet , Refeições , Nutricionistas , Projetos Piloto , Lanches
19.
BMC Med Educ ; 14: 239, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25404383

RESUMO

BACKGROUND: Globalization of the professions has become a necessity among schools and universities across the world. It has affected the medical and dental professions in terms of curriculum design and student and patient needs. In Japan, where medicine and dentistry are taught mainly in the Japanese language, profession-based courses in English, known as Medical English and Dental English, have been integrated into the existing curriculum among its 83 medical and 29 dental schools. Unfortunately, there is neither a core curriculum nor a model syllabus for these courses. METHODS: This report is based on a survey, two discussion forums, a workshop, and finally, the drafting of a proposed core curriculum for dental English approved by consensus of the participants from each university. RESULTS: The core curriculum covers the theoretical aspects, including dental English terms and oral pathologies; and practical aspects, including blended learning and dentist-patient communication. It is divided into modules and is recommended to be offered for at least two semesters. CONCLUSIONS: The core curriculum is expected to guide curriculum developers in schools where dental English courses are yet to be offered or are still in their early development. It may also serve as a model curriculum to medical and dental schools in countries in Asia, Europe, Africa, and Central and South America, where English is not the medium of instruction.


Assuntos
Currículo , Educação em Odontologia/organização & administração , Multilinguismo , Faculdades de Odontologia/organização & administração , Comparação Transcultural , Feminino , Humanos , Japão , Idioma , Masculino , Inovação Organizacional , Estudantes de Odontologia/estatística & dados numéricos
20.
J Strength Cond Res ; 27(11): 3216-20, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23439338

RESUMO

Global positioning system (GPS) watches have been introduced commercially, converting frequent measurements of time, location, speed (pace), and elevation into energy expenditure (EE) estimates. The purpose of this study was to compare EE estimates of 4 different GPS watches (Forerunner, Suunto, Polar, Adeo), at various walking speeds, with EE estimate from a triaxial accelerometer (RT3), which was used as a reference measure in this study. Sixteen healthy young adults completed the study. Participants wore 4 different GPS watches and an RT3 accelerometer and walked at 6-minute intervals on an outdoor track at 3 speeds (3, 5, and 7 km/hr). The statistical significance of differences in EE between the 3 watches was assessed using linear contrasts of the coefficients from the overall model. Reliability across trials for a given device was assessed using intraclass correlation coefficients as estimated in the mixed model. The GPS watches demonstrated lower reliability (intraclass correlation coefficient) across trials when compared with the RT3, particularly at the higher speed, 7 km/hr. Three GPS watches (Forerunner, Polar, and Suunto) significantly and consistently underestimated EE compared with the reference EE given by the RT3 accelerometer (average mean difference: Garmin, -50.5%; Polar, -41.7%; and Suunto, -41.7%; all p < 0.001). Results suggested that caution should be exercised when using commercial GPS watches to estimate EE in athletes during field-based testing and training.


Assuntos
Metabolismo Energético , Sistemas de Informação Geográfica/instrumentação , Caminhada/fisiologia , Acelerometria , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
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