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1.
Psychol Sport Exerc ; 74: 102693, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38960348

RESUMO

Outdoor programs involving recreational physical challenges are becoming increasingly popular for training and development purposes among adults, but rigorous studies investigating their effectiveness remain scarce. A randomized controlled trial was conducted to evaluate the effects of an outdoor adventure-based program on measures of self-efficacy, resilience, risk-taking propensity, and perceived stress. Participants were randomly assigned either to an intervention condition (half-day high ropes course) or a wait-list control group. Measures were taken at baseline and four days post-intervention and on the day to measure intervention perceptions. Significant increases in self-efficacy and risk-taking propensity were observed for the intervention arm compared to the control arm. Greater intervention engagement and affective valence ratings were associated with self-efficacy change. These findings highlight the practical relevance of adventure-based experiences for organizations and educational institutions seeking to enhance young adults' self-confidence. Additionally, they emphasize the importance of tailoring interventions to individual needs and ensuring positive participant experiences to achieve desired outcomes.


Assuntos
Recreação , Assunção de Riscos , Autoeficácia , Humanos , Masculino , Feminino , Adulto Jovem , Recreação/psicologia , Adulto , Estresse Psicológico/psicologia , Resiliência Psicológica , Adolescente
2.
Int J Sport Exerc Psychol ; 22(3): 553-571, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38859903

RESUMO

Although greater lifetime stressor exposure has been associated with physical and mental health issues in the general population, relatively little is known about how lifetime stressors impact the physical and mental health of elite athletes or the factors moderating this association. Given that many elite athletes show signs of perfectionism, and that this trait has been linked with ill-health, it is possible that perfectionism may moderate the lifetime stressor-health relationship. To test this possibility, we examined how cumulative lifetime stressor exposure was associated with general mental and physical health complaints in elite athletes, and the extent to which these associations were moderated by perfectionism. Participants were 110 elite athletes (64 female; M age = 29.98 years, SD = 10.54) who completed assessments of lifetime stressor exposure, physical health, psychological distress, and perfectionism. As hypothesised, hierarchical regression analyses revealed that experiencing more severe lifetime stressors was related to poorer physical and mental health. Furthermore, self-oriented perfectionism moderated the association between lifetime stressor count and severity and physical health, but not mental health. Overall, these data demonstrate stressor-specific effects among elite athletes and highlight the potential importance of assessing lifetime stressor exposure and perfectionistic tendencies in order to improve athlete health and well-being.

4.
J Food Sci ; 89(7): 3894-3916, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38865250

RESUMO

Food digestion is important for human health. Advances have been made using in vitro models to study food digestion, but there is considerable potential for numerical approaches in stomach modeling, as they can provide a comprehensive understanding of the complex flow and chemistry in the stomach. The focus of this study is to provide a concise review of the developed numerical stomach models over the past two decades. The gastric physiological parameters that are required for a computational model to represent the human gastric digestion process are discussed, including the stomach geometry, gastric motility, gastric emptying, and gastric secretions. Computational methods used to model gastric digestion are introduced and compared, including different computational fluid dynamics as well as solid mechanics methods. The challenges and limitations of current studies are discussed, as well as the areas for future research that need to be addressed. There has been progress in simulating gastric fluid flow with stomach wall motion, but much work remains to be done. The complex food breakdown mechanisms and a comprehensive chemical digestion process have not been implemented in any developed models. Numerical method that was once computationally expensive will be revolutionized as computing power continues to improve. Ultimately, the advancement of modeling of gastric food digestion will allow for additional hypothesis testing to streamline the development of food products that are beneficial to human health.


Assuntos
Digestão , Esvaziamento Gástrico , Modelos Biológicos , Estômago , Digestão/fisiologia , Humanos , Estômago/fisiologia , Esvaziamento Gástrico/fisiologia , Simulação por Computador , Hidrodinâmica
5.
Animals (Basel) ; 14(10)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38791719

RESUMO

Biological invasions are of special conservation concern in the Iberian Peninsula and other regions with high levels of endemism. Environmental variability, such as the seasonal fluctuations of Mediterranean streams, is a key factor that affects the spread of aquatic species in novel habitats. Fish parasites have a great potential to reflect such changes in the habitat features of freshwater ecosystems. The aim of this study consisted of seasonally analysing the health status and parasitological traits of non-native fish in Iberian waters. In particular, a strongly invasive population of Languedoc minnow Phoxinus septimaniae (leuciscid species native to south-east France) was assessed in Tordera Stream (north-eastern Iberian Peninsula, Mediterranean conditions). Fish were sampled in April, July, and October 2023 by electrofishing. Health status (external/internal organs) was significantly better in autumn (HAI = 28.8) than spring (HAI = 35.6). Life-cycle complexity was higher in spring (LCI = 1.98), whereas parasite abundance and Shannon diversity were significantly lower in autumn (TA = 19.6 and H' = 2.15, respectively). In October (more 'benign' environmental conditions in Iberian streams), minnows could display elevated foraging activity, with fish increasing their health condition and level of parasite resistance/tolerance. Overall results showed a particular seasonal profile of health and parasite infra-communities that allow this minnow species to thrive under highly fluctuating habitat conditions. This information could help environmental managers to control non-native fish in Mediterranean streams.

6.
JCI Insight ; 9(9)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564302

RESUMO

Loss-of-function (LoF) variants in the filaggrin (FLG) gene are the strongest known genetic risk factor for atopic dermatitis (AD), but the impact of these variants on AD outcomes is poorly understood. We comprehensively identified genetic variants through targeted region sequencing of FLG in children participating in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort. Twenty FLG LoF variants were identified, including 1 novel variant and 9 variants not previously associated with AD. FLG LoF variants were found in the cohort. Among these children, the presence of 1 or more FLG LoF variants was associated with moderate/severe AD compared with those with mild AD. Children with FLG LoF variants had a higher SCORing for Atopic Dermatitis (SCORAD) and higher likelihood of food allergy within the first 2.5 years of life. LoF variants were associated with higher transepidermal water loss (TEWL) in both lesional and nonlesional skin. Collectively, our study identifies established and potentially novel AD-associated FLG LoF variants and associates FLG LoF variants with higher TEWL in lesional and nonlesional skin.


Assuntos
Dermatite Atópica , Proteínas Filagrinas , Proteínas de Filamentos Intermediários , Mutação com Perda de Função , Fenótipo , Dermatite Atópica/genética , Dermatite Atópica/patologia , Humanos , Masculino , Feminino , Pré-Escolar , Estudos Prospectivos , Lactente , Proteínas de Filamentos Intermediários/genética , Predisposição Genética para Doença , Criança , Hipersensibilidade Alimentar/genética
7.
Cureus ; 16(2): e55194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435215

RESUMO

Background Perforated peptic ulcer disease has a high mortality rate, and there is consensus regarding the use of antifungals in the management of immunocompromised patients; however, there is variability in the utilization of antifungals in the non-immunocompromised cohort. This study aims to describe the current practice related to the use of antifungals in perforated peptic ulcer disease in Western Australia and to determine the peri-operative morbidity and mortality in the immunocompromised and non-immunocompromised cohort receiving antifungals. Methods Medical records of patients who underwent surgical repair of perforated peptic ulcer in all Western Australian tertiary hospitals between January 1, 2010, and December 31, 2017, were reviewed retrospectively. Data regarding pre-operative patient factors such as age, gender, and comorbidities, post-operative outcomes such as intra-abdominal sepsis/bleeding, peri-operative antifungal prescription, and abundance of fungal growth on intra-operative samples were collected. Results The study included 359 patients. The antifungal prescription was variable. An American Society of Anesthesiologists (ASA) score of 3 or more, presence of pre-operative shock and acidosis, and level of abundance of fungal growth on intra-operative samples were associated with antifungal prescription. Amongst the non-immunocompromised cohort, receiving antifungals was associated with higher morbidity. Conclusion The use of antifungals for patients with perforated peptic ulcer disease was variable. An ASA score of 3 or greater and pre-operative shock and acidosis are pre-operative factors predisposing patients to receiving antifungals. There was no difference in morbidity or mortality amongst immunocompromised patients regardless of antifungal prescription or non-prescription. However, in the non-immunocompromised cohort, those who received antifungals had a higher morbidity compared to those who did not.

8.
Nat Commun ; 15(1): 1944, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431703

RESUMO

Forecasting large earthquakes along active faults is of critical importance for seismic hazard assessment. Statistical models of recurrence intervals based on compilations of paleoseismic data provide a forecasting tool. Here we compare five models and use Bayesian model-averaging to produce time-dependent, probabilistic forecasts of large earthquakes along 93 fault segments worldwide. This approach allows better use of the measurement errors associated with paleoseismic records and accounts for the uncertainty around model choice. Our results indicate that although the majority of fault segments (65/93) in the catalogue favour a single best model, 28 benefit from a model-averaging approach. We provide earthquake rupture probabilities for the next 50 years and forecast the occurrence times of the next rupture for all the fault segments. Our findings suggest that there is no universal model for large earthquake recurrence, and an ensemble forecasting approach is desirable when dealing with paleoseismic records with few data points and large measurement errors.

9.
Innovation (Camb) ; 5(2): 100588, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38440259

RESUMO

The combination of urbanization and global warming leads to urban overheating and compounds the frequency and intensity of extreme heat events due to climate change. Yet, the risk of urban overheating can be mitigated by urban green-blue-grey infrastructure (GBGI), such as parks, wetlands, and engineered greening, which have the potential to effectively reduce summer air temperatures. Despite many reviews, the evidence bases on quantified GBGI cooling benefits remains partial and the practical recommendations for implementation are unclear. This systematic literature review synthesizes the evidence base for heat mitigation and related co-benefits, identifies knowledge gaps, and proposes recommendations for their implementation to maximize their benefits. After screening 27,486 papers, 202 were reviewed, based on 51 GBGI types categorized under 10 main divisions. Certain GBGI (green walls, parks, street trees) have been well researched for their urban cooling capabilities. However, several other GBGI have received negligible (zoological garden, golf course, estuary) or minimal (private garden, allotment) attention. The most efficient air cooling was observed in botanical gardens (5.0 ± 3.5°C), wetlands (4.9 ± 3.2°C), green walls (4.1 ± 4.2°C), street trees (3.8 ± 3.1°C), and vegetated balconies (3.8 ± 2.7°C). Under changing climate conditions (2070-2100) with consideration of RCP8.5, there is a shift in climate subtypes, either within the same climate zone (e.g., Dfa to Dfb and Cfb to Cfa) or across other climate zones (e.g., Dfb [continental warm-summer humid] to BSk [dry, cold semi-arid] and Cwa [temperate] to Am [tropical]). These shifts may result in lower efficiency for the current GBGI in the future. Given the importance of multiple services, it is crucial to balance their functionality, cooling performance, and other related co-benefits when planning for the future GBGI. This global GBGI heat mitigation inventory can assist policymakers and urban planners in prioritizing effective interventions to reduce the risk of urban overheating, filling research gaps, and promoting community resilience.

10.
Comput Biol Med ; 172: 108263, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489988

RESUMO

PROBLEM: Despite advances in Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO), a significant mortality rate persists due to complications. The non-physiological blood flow dynamics of VA-ECMO may lead to neurological complications and organ ischemia. Continuous retrograde high-flow oxygenated blood enters through a return cannula placed in the femoral artery which opposes the pulsatile deoxygenated blood ejected by the left ventricle (LV), which impacts upper body oxygenation and subsequent hyperoxemia. The complications underscore the critical need to comprehend the impact of VA-ECMO support level and return cannula size, as mortality remains a significant concern. AIM: The aim of this study is to predict and provide insights into the complications associated with VA-ECMO using computational fluid dynamics (CFD) simulations. These complications will be assessed by characterising blood flow and emboli transport patterns through a comprehensive analysis of the influence of VA-ECMO support levels and arterial return cannula sizes. METHODS: Patient-specific 3D aortic and major branch models, derived from a male patient's CT scan during VA-ECMO undergoing respiratory dysfunction, were analyzed using CFD. The investigation employed species transport and discrete particle tracking models to study ECMO blood (oxygenated) mixing with LV blood (deoxygenated) and to trace emboli transport patterns from potential sources (circuit, LV, and aorta wall). Two cannula sizes (15 Fr and 19 Fr) were tested alongside varying ECMO pump flow rates (50%, 70%, and 90% of the total cardiac output). RESULTS: Cannula size did not significantly affect oxygen transport. At 90% VA-ECMO support, all arteries distal to the aortic arch achieved 100% oxygen saturation. As support level decreased, oxygen transport to the upper body also decreased to a minimum saturation of 73%. Emboli transport varied substantially between emboli origin and VAECMO support level, with the highest risk of cerebral emboli coming from the LV with a 15 Fr cannula at 90% support. CONCLUSION: Arterial return cannula sizing minimally impacted blood oxygen distribution; however, it did influence the distribution of emboli released from the circuit and aortic wall. Notably, it was the support level alone that significantly affected the mixing zone of VA-ECMO and cardiac blood, subsequently influencing the risk of embolization of the cardiogenic source and oxygenation levels across various arterial branches.


Assuntos
Oxigenação por Membrana Extracorpórea , Masculino , Humanos , Hidrodinâmica , Hemodinâmica/fisiologia , Cateterismo , Oxigênio
11.
Comput Methods Programs Biomed ; 247: 108064, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382308

RESUMO

BACKGROUND AND OBJECTIVE: The movement of the respiratory walls has a significant impact on airflow through the respiratory tract. The majority of computational fluid dynamics (CFD) studies assume a static geometry which may not provide a realistic flow field. Furthermore, many studies use Reynolds Averaged Navier-Stokes (RANS) turbulence models that do not resolve turbulence structure. Combining the application of advanced scale-resolving turbulence models with moving respiratory walls using CFD will provide detailed insights into respiratory flow structures. METHODS: This study simulated a complete breathing cycle involving inhalation and exhalation in a nasal cavity to trachea geometry that incorporated moving glottis walls. A second breathing cycle was simulated with static glottis walls for comparison. A recently developed hybrid RANS-LES turbulence model, the Stress-Blended Eddy Simulation (SBES), was incorporated to resolve turbulent flow structures in fine detail for both transient simulations. Transient results were compared with steady-state RANS simulations for the same respiratory geometry. RESULTS: Glottis motion caused substantial effects on flow structure through the complete breathing cycle. Significant flow structure and velocity variations were observed due to glottal motion, primarily in the larynx and trachea. Resolved turbulence structures using SBES showed an intense mixing section in the glottis region during inhalation and in the nasopharynx during expiration, which was not present in the RANS simulations. CONCLUSION: Transient simulations of a realistic breathing cycle uncovered flow structures absent in simulations with a constant flow rate. Furthermore, the incorporation of glottis motion impacted airflow characteristics that suggest rigid respiratory walls do not accurately describe respiratory flow. Future research in respiratory airflow should be conducted using transient scale-resolving models in conjunction with moving respiratory walls to capture flow structures in detail.

12.
Psychophysiology ; 61(6): e14540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38361367

RESUMO

Outdoor adventure challenges are commonly used to enhance self-efficacy, but the physiological mechanisms involved remain unexplored. Additionally, while studies have documented the influence of self-efficacy on stress management, general self-efficacy has yet to be fully understood in the context of cardiovascular stress reactivity (CVR). This study investigated the influence of self-efficacy beliefs on CVR during acute psychological stress tasks. Additionally, it explored whether CVR serves as a novel mechanism underlying the outcomes of outdoor adventure challenges. As part of a wider randomized controlled trial, participants (n = 55) were invited to complete a laboratory session to assess CVR to an active (paced auditory serial addition test (PASAT)) and a passive (cold pressor test (CPT)) stress task. Randomized participants (n = 33) to the experimental condition also engaged in a high ropes challenge course after the laboratory session. It was found that greater self-reported self-efficacy was associated with larger CVR during the CPT and positively associated with perceived engagement and performance during the PASAT. Secondly, participants reporting positive change in self-efficacy post-intervention were associated with greater CVR and greater CVR was associated with higher ratings of intervention engagement and perceived challenge. This study provides preliminary evidence suggesting that greater efficacy beliefs may heighten CVR to passive acute psychological stressors. Habitual stress reactivity may represent a novel mechanism involved in outdoor and adventure-based interventions. Future research should continue to explore the impact of psychological variables on stress physiology and examine CVR as a potential mechanism in adventure experiences.


Assuntos
Frequência Cardíaca , Autoeficácia , Estresse Psicológico , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Estresse Psicológico/fisiopatologia
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