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1.
Nature ; 629(8014): 1015-1020, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38811709

RESUMO

Asteroids with diameters less than about 5 km have complex histories because they are small enough for radiative torques (that is, YORP, short for the Yarkovsky-O'Keefe-Radzievskii-Paddack effect)1 to be a notable factor in their evolution2. (152830) Dinkinesh is a small asteroid orbiting the Sun near the inner edge of the main asteroid belt with a heliocentric semimajor axis of 2.19 AU; its S-type spectrum3,4 is typical of bodies in this part of the main belt5. Here we report observations by the Lucy spacecraft6,7 as it passed within 431 km of Dinkinesh. Lucy revealed Dinkinesh, which has an effective diameter of only 720 m, to be unexpectedly complex. Of particular note is the presence of a prominent longitudinal trough overlain by a substantial equatorial ridge and the discovery of the first confirmed contact binary satellite, now named (152830) Dinkinesh I Selam. Selam consists of two near-equal-sized lobes with diameters of 210 m and 230 m. It orbits Dinkinesh at a distance of 3.1 km with an orbital period of about 52.7 h and is tidally locked. The dynamical state, angular momentum and geomorphologic observations of the system lead us to infer that the ridge and trough of Dinkinesh are probably the result of mass failure resulting from spin-up by YORP followed by the partial reaccretion of the shed material. Selam probably accreted from material shed by this event.

2.
Pain Med ; 20(7): 1430-1448, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30986301

RESUMO

OBJECTIVE: Approximately 55-76% of Service members use dietary supplements for various reasons; although such use has become popular for a wide range of pain conditions, decisions to use supplements are often driven by information that is not evidence-based. This work evaluates whether the current research on dietary ingredients for chronic musculoskeletal pain provides sufficient evidence to inform decisions for practice and self-care, specifically for Special Operations Forces personnel. METHODS: A steering committee convened to develop research questions and factors required for decision-making. Key databases were searched through August 2016. Eligible systematic reviews and randomized controlled trials were assessed for methodological quality. Meta-analysis was applied where feasible. GRADE was used to determine confidence in the effect estimates. A decision table was constructed to make evidence-informed judgments across factors required for decision-making, and recommendations were made for practice and self-care use. RESULTS: Nineteen dietary ingredients were included. Conditional evidence-based recommendations were made for the use of avocado soybean unsaponifiables, capsaicin, curcuma, ginger, glucosamine, melatonin, polyunsaturated fatty acids, and vitamin D. In these cases, desirable effects outweighed undesirable effects, but there was uncertainty about the trade-offs, either because the evidence was low quality or because benefits and downsides were closely balanced. CONCLUSIONS: The evidence showed that certain dietary ingredients, when taken as part of a balanced diet and/or as a supplement (e.g., pill, tablet, capsule, cream), may alleviate musculoskeletal pain with no to minimal risk of harm. This finding emphasizes and reinforces the critical importance of shared decision-making between Operators and their health care providers.


Assuntos
Técnicas de Apoio para a Decisão , Suplementos Nutricionais , Dor Musculoesquelética , Pessoal Administrativo , Dor Crônica , Dieta , Medicina Baseada em Evidências , Pessoal de Saúde , Humanos
3.
Pain Med ; 20(8): 1619-1632, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30986310

RESUMO

OBJECTIVE: Approximately 55-76% of Service members use dietary supplements for various reasons; although such use has become popular, decisions are often driven by information that is not evidence-based. This work evaluates whether current research on dietary ingredients for chronic musculoskeletal pain provides sufficient evidence to inform decisions for practice and self-care, specifically for Special Operations Forces personnel. METHODS: A steering committee convened to develop research questions and factors required for decision-making. Key databases were searched through August 2016. Eligible systematic reviews and randomized controlled trials were assessed for methodological quality. Meta-analysis was applied where feasible. Grading of Recommendations, Assessment, Development and Evaluation was used to determine confidence in the effect estimates. The committee used a decision table to make evidence-informed judgments across decision-making factors and recommendations for practice and self-care use. RESULTS: Nineteen dietary ingredients were assessed. No recommendations were given for boswellia, ginger, rose hip, or s-adenosyl-L-methionine (SAMe); specifically, although ginger can be obtained via food, no recommendation is provided for use as a supplement due to unclear research. Further, there were insufficient strong research on boswellia and SAMe and possible compliance issues (i.e., high number of capsules required daily) associated with rose hip. CONCLUSIONS: No recommendations were made when the evidence was low quality or trade-offs were so closely balanced that any recommendation would be too speculative. Research recommendations are provided to enhance the quality and body of evidence for the most promising ingredients. Clinicians and those with chronic pain can rely on evidence-based recommendations to inform their decisions.


Assuntos
Dor Crônica/terapia , Suplementos Nutricionais , Militares , Dor Musculoesquelética/terapia , Guias de Prática Clínica como Assunto , Medicina Baseada em Evidências , Humanos , Manejo da Dor , Autocuidado , Autogestão
4.
Pain Med ; 20(6): 1236-1247, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30986309

RESUMO

OBJECTIVE: Approximately 55-76% of Service members use dietary supplements for various reasons, including pain and related outcomes. This work evaluates current research on dietary ingredients for chronic musculoskeletal pain to inform decisions for practice and self-care, specifically for Special Operations Forces personnel. METHODS: A steering committee convened to develop research questions and factors required for decision-making. Key databases were searched through August 2016. Eligible systematic reviews and randomized controlled trials were assessed for methodological quality. Meta-analysis was applied where feasible. GRADE was used to determine confidence in the effect estimates. The committee made evidence-informed judgments and recommendations for practice and self-care use. RESULTS: Nineteen eligible dietary ingredients were assessed for quality, efficacy, and safety. Avocado soybean unsaponifiables, capsaicin, curcuma, ginger (as a food source), glucosamine, melatonin, polyunsaturated fatty acids, and vitamin D were conditionally recommended as their benefits outweighed risks, but there was still some uncertainty about the trade-offs. No recommendations were made for boswellia, ginger (as a dietary supplement), rose hip, or s-adenosyl-L-methionine. Recommendations were made against the use of collagen, creatine, devil's claw, l-carnitine, methylsulfonylmethane, pycnogenol, willow bark extract, and vitamin E. Research priorities were developed to address gaps precluding stronger recommendations. CONCLUSIONS: Currently the scientific evidence is insufficiently robust to establish definitive clinical practice guidelines, but processes could be established to track the impact of these ingredients. Until then, providers have the evidence needed to make informed decisions about the safe use of these dietary ingredients, and future research can address existing gaps.


Assuntos
Suplementos Nutricionais , Medicina Baseada em Evidências/métodos , Medicina Militar/métodos , Militares , Dor Musculoesquelética/dietoterapia , Guias de Prática Clínica como Assunto , Medicina Baseada em Evidências/normas , Humanos , Medicina Militar/normas , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/epidemiologia , Fitoterapia/métodos , Fitoterapia/normas , Guias de Prática Clínica como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas
5.
Environ Resour Econ (Dordr) ; 70(3): 631-650, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30166775

RESUMO

Forests are often touted for their ecosystem services, including outdoor recreation. Historically forests were a source of danger and were avoided. Forests continue to be reservoirs for infectious diseases and their vectors - a disservice. We examine how this disservice undermines the potential recreational services by measuring the human response to environmental risk using exogenous variation in the risk of contracting Lyme Disease. We find evidence that individuals substitute away from spending time outdoors when there is greater risk of Lyme Disease infection. Individuals facing a higher risk of infection substitute away from outdoor leisure. On average individuals spent 1.54 fewer minutes outdoors at the average, 72 U.S. Centers for Disease Control and Prevention (CDC), confirmed cases of Lyme Disease. We estimate lost outdoor recreation of 9.41 hours per year per person in an average county in the North Eastern United States and an aggregate welfare loss on the order $2.8 billion to $5.0 billion per year.

6.
Environ Resour Econ (Dordr) ; 70(3): 713-730, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32214673

RESUMO

Most models designed to understand how to manage infected wildlife systems with bioeconomic multi-stability take the initial conditions as given, thereby treating pathogen invasion as unanticipated. We examine how ex ante management is an opportunity to influence the ex post conditions, which in turn affect the ex post optimal outcome. To capture these ex ante management choices, we extend the Poisson "collapse" model of Reed and Heras (Bull Math Biol 54:185-207, 1992) to allow for endogenous initial conditions and ex post multi-stability. We account for two uncertain processes: the introduction and establishment of the pathogen. Introduction is conditional on anthropogenic investments in prevention, and both random processes are conditional on how we manage the native population to provide natural prevention of invasion and natural insurance against establishment placing the system in an undesirable basin of attraction. We find that both multi-stability of the invaded system and these uncertainty processes can create economic non-convexities that yield multiple candidate solutions to the ex ante optimization problem. Additionally, we illustrate how the nature of natural protection against introduction and establishment risks can play an important role in the allocation of anthropogenic investments.

7.
Br J Nutr ; 117(9): 1257-1269, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28534446

RESUMO

Military personnel generally under-consume n-3 fatty acids and overconsume n-6 fatty acids. In a placebo-controlled, double-blinded study, we investigated whether a diet suitable for implementation in military dining facilities and civilian cafeterias could benefit n-3/n-6 fatty acid status of consumers. Three volunteer groups were provided different diets for 10 weeks. Control (CON) participants consumed meals from the US Military's Standard Garrison Dining Facility Menu. Experimental, moderate (EXP-Mod) and experimental-high (EXP-High) participants consumed the same meals, but high n-6 fatty acid and low n-3 fatty acid containing chicken, egg, oils and food ingredients were replaced with products having less n-6 fatty acids and more n-3 fatty acids. The EXP-High participants also consumed smoothies containing 1000 mg n-3 fatty acids per serving, whereas other participants received placebo smoothies. Plasma and erythrocyte EPA and DHA in CON group remained unchanged throughout, whereas EPA, DHA and Omega-3 Index increased in EXP-Mod and EXP-High groups, and were higher than in CON group after 5 weeks. After 10 weeks, Omega-3 Index in EXP-High group had increased further. No participants exhibited changes in fasting plasma TAG, total cholesterol, LDL, HDL, mood or emotional reactivity. Replacing high linoleic acid (LA) containing foods in dining facility menus with similar high oleic acid/low LA and high n-3 fatty acid foods can improve n-6/n-3 blood fatty acid status after 5 weeks. The diets were well accepted and suitable for implementation in group feeding settings like military dining facilities and civilian cafeterias.


Assuntos
Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-6/administração & dosagem , Lipídeos/sangue , Adulto , Dieta , Emoções/efeitos dos fármacos , Feminino , Análise de Alimentos , Humanos , Masculino , Militares , Estados Unidos , Adulto Jovem
8.
J Head Trauma Rehabil ; 32(3): E27-E37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27603765

RESUMO

OBJECTIVE: This systematic review examines the efficacy of hyperbaric oxygen (HBO2) for traumatic brain injury (TBI) to make evidence-based recommendations for its application and future research. METHODS: A comprehensive search was conducted to identify studies through 2014. Methodological quality was assessed and synthesis and interpretation of relevant data was performed. RESULTS: Twelve randomized trials were included. All mild TBI studies demonstrated minimal bias and no statistically significant differences between HBO2 and sham arms. Statistically significant improvement occurred over time within both groups. Moderate-to-severe TBI studies were of mixed quality, with majority of results favoring HBO2 compared with "standard care." The placebo analysis conducted was limited by lack of details. CONCLUSIONS: For mild TBI, results indicate HBO2 is no better than sham treatment. Improvements within both HBO2 and sham groups cannot be ignored. For acute treatment of moderate-to-severe TBI, although methodology appears flawed across some studies, because of the complexity of brain injury, HBO2 may be beneficial as a relatively safe adjunctive therapy if feasible. Further research should be considered to resolve the controversy surrounding this field, but only if methodological flaws are avoided and bias minimized.


Assuntos
Concussão Encefálica/diagnóstico , Concussão Encefálica/terapia , Oxigenoterapia Hiperbárica/métodos , Guias de Prática Clínica como Assunto , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
9.
J Econ Dyn Control ; 51: 166-179, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27642202

RESUMO

There is a growing concern that risks of disease outbreak and pandemics are increasing over time. We consider optimal investments in prevention before an outbreak using an endogenous risk approach within an optimal control setting. Using the threat of pandemic influenza as an illustrative example, we demonstrate that prevention expenditures are relatively small in comparison to the potential losses facing the USA, and these expenditures need to be flexible and responsive to changes in background risk. Failure to adjust these expenditures to changes in background risk poses a significant threat to social welfare into the future.

10.
Econ Hum Biol ; 52: 101314, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38056317

RESUMO

Outbreaks of COVID-19 in crowded work locations led to mass infection events during the pandemic that stressed health capacity in rural communities. This led to disparate responses - either isolating and restricting workers to facilities and potentially amplifying spread between them, more intense community wide restrictions, or an acceptance of higher disease spread. An extreme case is the salmon fishery in Bristol Bay, Alaska, where fishermen, factory workers, and residents all interact during the summer fishing season. During the pandemic, policy measures were debated, including community mask mandates, restricting workers to their boats and factories, and even closing the valuable seasonal fishery. We develop an agent-based SIR model (ABM) to examine COVID-19 transmission in a resource-dependent community populated by distinct subgroups. The model includes a virus spreading within and between three heterogenous populations who interact with other members of their type in their home location, and with different types of agents when out in the community. We simulate various non-pharmaceutical interventions and vaccination rates across these groups. Results demonstrate the efficacy of non-pharmaceutical interventions and vaccinations, as well as tradeoffs between duration and intensity and tradeoffs between groups impacted by the outbreak. This ABM demonstrates the impact of public policy mechanisms on health outcomes in resource-dependent communities with distinct populations.


Assuntos
COVID-19 , Humanos , Pandemias , Surtos de Doenças , Vacinação , Local de Trabalho
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