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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35058364

RESUMO

While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evaluated evidence for the effects of temporal, static, and dynamic area closures on the bycatch and target catch of 15 fisheries around the world. Assuming perfect knowledge of where the catch and bycatch occurs and a closure of 30% of the fishing area, we found that dynamic area closures could reduce bycatch by an average of 57% without sacrificing catch of target species, compared to 16% reductions in bycatch achievable by static closures. The degree of bycatch reduction achievable for a certain quantity of target catch was related to the correlation in space and time between target and bycatch species. If the correlation was high, it was harder to find an area to reduce bycatch without sacrificing catch of target species. If the goal of spatial closures is to reduce bycatch, our results suggest that dynamic management provides substantially better outcomes than classic static marine area closures. The use of dynamic ocean management might be difficult to implement and enforce in many regions. Nevertheless, dynamic approaches will be increasingly valuable as climate change drives species and fisheries into new habitats or extended ranges, altering species-fishery interactions and underscoring the need for more responsive and flexible regulatory mechanisms.


Assuntos
Pesqueiros , Conservação dos Recursos Naturais , Ecossistema , Oceanografia
2.
PLoS Comput Biol ; 19(9): e1010526, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37683013

RESUMO

Integrating sensory information during movement and adapting motor plans over successive movements are both essential for accurate, flexible motor behaviour. When an ongoing movement is off target, feedback control mechanisms update the descending motor commands to counter the sensed error. Over longer timescales, errors induce adaptation in feedforward planning so that future movements become more accurate and require less online adjustment from feedback control processes. Both the degree to which sensory feedback is integrated into an ongoing movement and the degree to which movement errors drive adaptive changes in feedforward motor plans have been shown to scale inversely with sensory uncertainty. However, since these processes have only been studied in isolation from one another, little is known about how they are influenced by sensory uncertainty in real-world movement contexts where they co-occur. Here, we show that sensory uncertainty may impact feedforward adaptation of reaching movements differently when feedback integration is present versus when it is absent. In particular, participants gradually adjust their movements from trial-to-trial in a manner that is well characterised by a slow and consistent envelope of error reduction. Riding on top of this slow envelope, participants exhibit large and abrupt changes in their initial movement vectors that are strongly correlated with the degree of sensory uncertainty present on the previous trial. However, these abrupt changes are insensitive to the magnitude and direction of the sensed movement error. These results prompt important questions for current models of sensorimotor learning under uncertainty and open up new avenues for future exploration in the field.


Assuntos
Aprendizagem , Desempenho Psicomotor , Humanos , Retroalimentação , Incerteza , Movimento , Retroalimentação Sensorial , Adaptação Fisiológica
3.
Neuroimage ; 180(Pt A): 88-100, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28793239

RESUMO

The application of machine learning methods to neuroimaging data has fundamentally altered the field of cognitive neuroscience. Future progress in understanding brain function using these methods will require addressing a number of key methodological and interpretive challenges. Because these challenges often remain unseen and metaphorically "haunt" our efforts to use these methods to understand the brain, we refer to them as "ghosts". In this paper, we describe three such ghosts, situate them within a more general framework from philosophy of science, and then describe steps to address them. The first ghost arises from difficulties in determining what information machine learning classifiers use for decoding. The second ghost arises from the interplay of experimental design and the structure of information in the brain - that is, our methods embody implicit assumptions about information processing in the brain, and it is often difficult to determine if those assumptions are satisfied. The third ghost emerges from our limited ability to distinguish information that is merely decodable from the brain from information that is represented and used by the brain. Each of the three ghosts place limits on the interpretability of decoding research in cognitive neuroscience. There are no easy solutions, but facing these issues squarely will provide a clearer path to understanding the nature of representation and computation in the human brain.


Assuntos
Mapeamento Encefálico/métodos , Neurociência Cognitiva/métodos , Aprendizado de Máquina , Humanos , Análise Multivariada
5.
Conserv Biol ; 30(4): 783-91, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26632250

RESUMO

The North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery. This is made difficult by the scarcity of records over this species' long whaling history. We sought to estimate the preexploitation population size of the North Atlantic right whale and understand how this species was distributed across its range. We used a spatially explicit data set on historical catches of North Pacific right whales (NPRWs) (Eubalaena japonica) to model the relationship between right whale relative density and the environment during the summer feeding season. Assuming the 2 right whale species select similar environments, we projected this model to the North Atlantic to predict how the relative abundance of NARWs varied across their range. We calibrated these relative abundances with estimates of the NPRW total prewhaling population size to obtain high and low estimates for the overall NARW population size prior to exploitation. The model predicted 9,075-21,328 right whales in the North Atlantic. The current NARW population is thus <6% of the historical North Atlantic carrying capacity and has enormous potential for recovery. According to the model, in June-September NARWs concentrated in 2 main feeding areas: east of the Grand Banks of Newfoundland and in the Norwegian Sea. These 2 areas may become important in the future as feeding grounds and may already be used more regularly by this endangered species than is thought.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Baleias , Animais , Oceano Atlântico , Densidade Demográfica , Dinâmica Populacional
6.
Proc Natl Acad Sci U S A ; 110(51): 20617-20, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24297882

RESUMO

Trophic levels are critical for synthesizing species' diets, depicting energy pathways, understanding food web dynamics and ecosystem functioning, and monitoring ecosystem health. Specifically, trophic levels describe the position of species in a food web, from primary producers to apex predators (range, 1-5). Small differences in trophic level can reflect large differences in diet. Although trophic levels are among the most basic information collected for animals in ecosystems, a human trophic level (HTL) has never been defined. Here, we find a global HTL of 2.21, i.e., the trophic level of anchoveta. This value has increased with time, consistent with the global trend toward diets higher in meat. National HTLs ranging between 2.04 and 2.57 reflect a broad diversity of diet, although cluster analysis of countries with similar dietary trends reveals only five major groups. We find significant links between socio-economic and environmental indicators and global dietary trends. We demonstrate that the HTL is a synthetic index to monitor human diets and provides a baseline to compare diets between countries.


Assuntos
Cadeia Alimentar , Preferências Alimentares , Carne , Modelos Biológicos , Animais , Humanos
7.
Behav Brain Sci ; 39: e124, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27561900

RESUMO

Functional fingerprints aggregate over heterogeneous tasks, protocols, and controls. The appearance of functional diversity might be explained by task heterogeneity and conceptual imprecision.


Assuntos
Encéfalo/fisiologia , Humanos
8.
Ecology ; 96(8): 2236-44, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26405748

RESUMO

Three indices of larval retention have been used in the literature to assess the tendency for self-maintenance of local marine populations: local retention (LR), self-recruitment (SR), and relative local retention (RLR). Only one of these, LR, defined as the ratio of locally produced settlement to local egg production, has a clear relationship to self-persistence of individual sites. However, SR, the ratio of locally produced settlement to settlement of all origins at a site, is generally easier to measure experimentally. We use theoretical, simulation, and empirical approaches to bridge the gap between these different indices, and demonstrate that there is a proportional relationship between SR and LR, for metapopulations close to a stable state and with lifetime egg production (LEP) approximately uniform over space. Similarly, for systems where larval mortality rates are a relatively uniform function of release site, RLR (defined as the ratio of locally produced settlement to all settlement of local origin) and LR will also be proportional. Therefore, SR and RLR provide information on relative rates of LR for systems satisfying these conditions. Furthermore, the ratio between LR and SR can be used to evaluate global persistence of metapopulations, and therefore provides valuable information not necessarily available if only LR is considered.


Assuntos
Distribuição Animal/fisiologia , Peixes/fisiologia , Modelos Biológicos , Animais , Simulação por Computador , Ecossistema , Larva/fisiologia , Ovulação/fisiologia , Dinâmica Populacional
9.
J Med Internet Res ; 17(10): e224, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26441467

RESUMO

BACKGROUND: Adoptions of health behaviors are crucial for maintaining good health after type 2 diabetes mellitus (T2DM) diagnoses. However, adherence to glucoregulating behaviors like regular exercise and balanced diet can be challenging, especially for people living in lower-socioeconomic status (SES) communities. Providing cost-effective interventions that improve self-management is important for improving quality of life and the sustainability of health care systems. OBJECTIVE: To evaluate a health coach intervention with and without the use of mobile phones to support health behavior change in patients with type 2 diabetes. METHODS: In this noninferiority, pragmatic randomized controlled trial (RCT), patients from two primary care health centers in Toronto, Canada, with type 2 diabetes and a glycated hemoglobin/hemoglobin A1c (HbA1c) level of ≥7.3% (56.3 mmol/mol) were randomized to receive 6 months of health coaching with or without mobile phone monitoring support. We hypothesized that both approaches would result in significant HbA1c reductions, although health coaching with mobile phone monitoring would result in significantly larger effects. Participants were evaluated at baseline, 3 months, and 6 months. The primary outcome was the change in HbA1c from baseline to 6 months (difference between and within groups). Other outcomes included weight, waist circumference, body mass index (BMI), satisfaction with life, depression and anxiety (Hospital Anxiety and Depression Scale [HADS]), positive and negative affect (Positive and Negative Affect Schedule [PANAS]), and quality of life (Short Form Health Survey-12 [SF-12]). RESULTS: A total of 138 patients were randomized and 7 were excluded for a substudy; of the remaining 131, 67 were allocated to the intervention group and 64 to the control group. Primary outcome data were available for 97 participants (74.0%). While both groups reduced their HbA1c levels, there were no significant between-group differences in change of HbA1c at 6 months using intention-to-treat (last observation carried forward [LOCF]) (P=.48) or per-protocol (P=.83) principles. However, the intervention group did achieve an accelerated HbA1c reduction, leading to a significant between-group difference at 3 months (P=.03). This difference was reduced at the 6-month follow-up as the control group continued to improve, achieving a reduction of 0.81% (8.9 mmol/mol) (P=.001) compared with a reduction of 0.84% (9.2 mmol/mol)(P=.001) in the intervention group. Intervention group participants also had significant decreases in weight (P=.006) and waist circumference (P=.01) while controls did not. Both groups reported improvements in mood, satisfaction with life, and quality of life. CONCLUSIONS: Health coaching with and without access to mobile technology appeared to improve glucoregulation and mental health in a lower-SES, T2DM population. The accelerated improvement in the mobile phone group suggests the connectivity provided may more quickly improve adoption and adherence to health behaviors within a clinical diabetes management program. Overall, health coaching in primary care appears to lead to significant benefits for patients from lower-SES communities with poorly controlled type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT02036892; http://clinicaltrials.gov/ct2/show/NCT02036892 (Archived by WebCite at http://www.webcitation.org/6b3cJYJOD).


Assuntos
Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas/química , Atenção Primária à Saúde/métodos , Telemedicina/métodos , Adulto , Idoso , Feminino , Hemoglobinas Glicadas/análise , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Classe Social
11.
Clin Psychol Rev ; 108: 102378, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38232573

RESUMO

The Reading the Mind in the Eyes Test (RMET) is one of the most influential measures of social cognitive ability, and it has been used extensively in clinical populations. However, questions have been raised about the validity of RMET scores. We conducted a systematic scoping review of the validity evidence reported in studies that administered the RMET (n = 1461; of which 804 included at least one clinical sample) with a focus on six key dimensions: internal consistency, test-retest reliability, factor structure, convergent validity, discriminant validity, and known group validity. Strikingly, 63% of these studies failed to provide validity evidence from any of these six categories. Moreover, when evidence was reported, it frequently failed to meet widely accepted validity standards. Overall, our results suggest a troubling conclusion: the validity of RMET scores (and the research findings based on them) are largely unsubstantiated and uninterpretable. More broadly, this project demonstrates how unaddressed measurement issues can undermine a voluminous psychological literature.


Assuntos
Sintomas Afetivos , Cognição , Humanos , Reprodutibilidade dos Testes , Olho , Habilidades Sociais
12.
Behav Brain Sci ; 36(5): 553-4; discussion 571-87, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24103607

RESUMO

Jeffery et al. characterize the egocentric/allocentric distinction as discrete. But paradoxically, much of the neural and behavioral evidence they adduce undermines a discrete distinction. More strikingly, their positive proposal - the bicoded map hypothesis - reflects a more complex interplay between egocentric and allocentric coding than they acknowledge. Properly interpreted, their proposal about three-dimensional spatial representation contributes to recent work on embodied cognition.


Assuntos
Cognição/fisiologia , Modelos Neurológicos , Percepção Espacial/fisiologia , Comportamento Espacial , Animais , Humanos
13.
J Neuropsychol ; 17(1): 108-124, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36124357

RESUMO

We examined the impact of conventional versus robust normative approaches on cognitive characterization and clinical classification of MCI versus dementia. The sample included participants from the National Alzheimer's Coordinating Center Uniform Data Set. Separate demographically adjusted z-scores for cognitive tests were derived from conventional (n = 4273) and robust (n = 602) normative groups. To assess the impact of deriving scores from a conventional versus robust normative group on cognitive characterization, we examined likelihood of having a low score on each neuropsychological test. Next, we created receiver operating characteristic (ROC) curves for the ability of normed scores derived from each normative group to differentiate between MCI (n = 3570) and dementia (n = 1564). We examined the impact of choice of normative group on classification accuracy by comparing sensitivity and specificity values and areas under the curves (AUC). Compared with using a conventional normative group, using a robust normative group resulted in a higher likelihood of low cognitive scores for individuals classified with MCI and dementia. Comparison of the classification accuracy for distinguishing MCI from dementia did not suggest a statistically significant advantage for either normative approach (Z = -0.29, p = .77; AUC = 0.86 for conventional and AUC = 0.86 for robust). In summary, these results indicate that using a robust normative group increases the likelihood of characterizing cognitive performance as low. However, there is not a clear advantage of using a robust over a conventional normative group when differentiating between MCI and dementia.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Testes Neuropsicológicos , Sensibilidade e Especificidade , Cognição
14.
Mar Pollut Bull ; 187: 114497, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36646000

RESUMO

Vast quantities of debris are beaching at remote islands in the western Indian Ocean. We carry out marine dispersal simulations incorporating currents, waves, winds, beaching, and sinking, for both terrestrial and marine sources of debris, to predict where this debris comes from. Our results show that most terrestrial debris beaching at these remote western Indian Ocean islands drifts from Indonesia, India, and Sri Lanka. Debris associated with fisheries and shipping also poses a major risk. Debris accumulation at Seychelles is likely seasonal, peaking during February-April. This pattern is driven by monsoonal winds and may be amplified during positive Indian Ocean Dipole and El-Niño events. Our results underline the vulnerability of small island states to marine plastic pollution, and are a crucial step towards improved management of the issue. The trajectories used in this study are available for download, and our analyses can be rerun under different parameter choices.


Assuntos
Monitoramento Ambiental , Resíduos , Seicheles , Oceano Índico , Resíduos/análise , Monitoramento Ambiental/métodos , Poluição da Água/análise , Plásticos
15.
Autism ; : 13623613231211967, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38006222

RESUMO

LAY ABSTRACT: Autistic people have been said to have 'problems' with joint attention, that is, looking where someone else is looking. Past studies of joint attention have used tasks that require autistic people to continuously look at and respond to eye-gaze cues. But joint attention can also be done using other social cues, like pointing. This study looked at whether autistic and non-autistic young people use another person's eye gaze during joint attention in a task that did not require them to look at their partner's face. In the task, each participant worked together with their partner to find a computer-generated object in virtual reality. Sometimes the participant had to help guide their partner to the object, and other times, they followed their partner's lead. Participants were told to point to guide one another but were not told to use eye gaze. Both autistic and non-autistic participants often looked at their partner's face during joint attention interactions and were faster to respond to their partner's hand-pointing when the partner also looked at the object before pointing. This shows that autistic people can and do use information from another person's eyes, even when they don't have to. It is possible that, by not forcing autistic young people to look at their partner's face and eyes, they were better able to gather information from their partner's face when needed, without being overwhelmed. This shows how important it is to design tasks that provide autistic people with opportunities to show what they can do.

18.
PLoS One ; 17(10): e0276258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36264853

RESUMO

Deep learning-based approaches to markerless 3D pose estimation are being adopted by researchers in psychology and neuroscience at an unprecedented rate. Yet many of these tools remain unvalidated. Here, we report on the validation of one increasingly popular tool (DeepLabCut) against simultaneous measurements obtained from a reference measurement system (Fastrak) with well-known performance characteristics. Our results confirm close (mm range) agreement between the two, indicating that under specific circumstances deep learning-based approaches can match more traditional motion tracking methods. Although more work needs to be done to determine their specific performance characteristics and limitations, this study should help build confidence within the research community using these new tools.


Assuntos
Aprendizado Profundo , Movimento (Física)
20.
Trends Neurosci ; 44(6): 478-491, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33637286

RESUMO

The mirror neuron system has dominated understanding of observational learning from a cognitive neuroscience perspective. Our review highlights the value of observational learning frameworks that integrate a more diverse and distributed set of cognitive and brain systems, including those implicated in sensorimotor transformations, as well as in more general processes such as executive control, reward, and social cognition. We argue that understanding how observational learning occurs in the real world will require neuroscientific frameworks that consider how visuomotor processes interface with more general aspects of cognition, as well as how learning context and action complexity shape mechanisms supporting learning from watching others.


Assuntos
Neurociência Cognitiva , Neurônios-Espelho , Encéfalo , Cognição , Humanos , Recompensa
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