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1.
Proc Natl Acad Sci U S A ; 120(22): e2208654120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216522

RESUMO

The development of precise neural circuits in the brain requires spontaneous patterns of neural activity prior to functional maturation. In the rodent cerebral cortex, patchwork and wave patterns of activity develop in somatosensory and visual regions, respectively, and are present at birth. However, whether such activity patterns occur in noneutherian mammals, as well as when and how they arise during development, remain open questions relevant for understanding brain formation in health and disease. Since the onset of patterned cortical activity is challenging to study prenatally in eutherians, here we offer an approach in a minimally invasive manner using marsupial dunnarts, whose cortex forms postnatally. We discovered similar patchwork and travelling waves in the dunnart somatosensory and visual cortices at stage 27 (equivalent to newborn mice) and examined earlier stages of development to determine the onset of these patterns and how they first emerge. We observed that these patterns of activity emerge in a region-specific and sequential manner, becoming evident as early as stage 24 in somatosensory and stage 25 in visual cortices (equivalent to embryonic day 16 and 17, respectively, in mice), as cortical layers establish and thalamic axons innervate the cortex. In addition to sculpting synaptic connections of existing circuits, evolutionarily conserved patterns of neural activity could therefore help regulate other early events in cortical development.


Assuntos
Córtex Cerebral , Marsupiais , Animais , Camundongos , Axônios , Mamíferos , Encéfalo , Eutérios , Córtex Somatossensorial
2.
Stroke ; 55(5): 1278-1287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38533647

RESUMO

BACKGROUND: Cumulative evidence suggests a correlation between physical or mental activity and the risk of stroke. However, the combined impact of these activities on stroke onset remains unexplored. This study identified physical and mental activity patterns using principal component analysis and investigated their associations with risk of incident stroke in the general population. METHODS: Our study was sourced from the UK Biobank cohort between 2006 and 2010. Information on physical and mental-related activities were obtained through a touch-screen questionnaire. The incident stroke was diagnosed by physicians and subsequently verified through linkage to Hospital Episode Statistics. Principal component analysis was used to identify potential physical and mental activity patterns. Cox proportional hazard regression models were performed to calculate hazard ratios (HRs) and 95% CIs of incident stroke, adjusting for potential confounders. RESULTS: The initial UK Biobank cohort originally consisted of 502 411 individuals, of whom a total of 386 902 participants (aged 38-79 years) without any history of stroke at baseline were included in our study. During a median follow-up of 7.7 years, 6983 (1.8%) cases of stroke were documented. The mean age of the included participants was 55.9 years, and the proportion of women was 55.1%. We found that multiple individual items related to physical and mental activity showed significant associations with risk of stroke. We identified 4 patterns of physical activity and 3 patterns of mental activity using principal component analysis. The adherence to activity patterns of vigorous exercise, housework, and walking predominant patterns were associated with a lower risk of stroke by 17% (HR, 0.83 [95% CI, 0.78-0.89]; 20% (HR, 0.80 [95% CI, 0.75-0.85]; and 20% (HR, 0.80 [95% CI, 0.75-0.86), respectively. Additionally, the transportation predominant pattern (HR, 1.36 [95% CI, 1.28-1.45) and watching TV pattern (HR, 1.43 [95% CI, 1.33-1.53) were found to be significantly associated with a higher risk of stroke. These associations remained consistent across all subtypes of stroke. CONCLUSIONS: Activity patterns mainly related to frequent vigorous exercise, housework, and walking were associated with lower risks of stroke and all its subtypes. Our findings provide new insights for promoting suitable patterns of physical and mental activity for primary prevention of stroke.

3.
Int J Behav Nutr Phys Act ; 21(1): 5, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191365

RESUMO

BACKGROUND: There is limited understanding of the extent to which differences in physical activity across the day and week may be associated with mental wellbeing. Such an understanding is needed for better targeting of interventions. In this study, we describe total and temporal patterning of physical activity across the week in adolescents (age 13-14y) and assess their prospective associations with mental wellbeing. METHODS: 1,983 13-14-year-old adolescent participants based in Cambridgeshire and Essex, recruited between 2016 and 2017 into the Get Others Active Trial provided data at baseline and 4 months. Physical activity was measured at baseline using wrist-worn accelerometers across different time segments (whole week, weekday schooltime, weekday out of school, and weekend), and operationalized as average movement-related acceleration for each time segment. Mental Wellbeing at baseline and 4 months was measured using the Warwick Edinburgh MentalWellbeing Scale. Associations between physical activity across different time segments (whole week, weekday schooltime, weekday out of school, and weekend) and mental wellbeing at 4 months were investigated using sex-stratified multi-level regression models, adjusted for covariates, and both adjusted and unadjusted for baseline mental wellbeing. RESULTS: Our analyses found positive associations between physical activity and mental wellbeing at 4 months, unadjusted for baseline wellbeing. Among girls, positive associations were shown when considering physical activity across the whole week 0.07 (95% CI, 0.03-0.12), and across all separate time periods studied: weekday schooltime 0.07 (95% CI, 0.02-0.11), weekday out-of-school time 0.07 (95% CI, 0.03-0.12), and weekend 0.07 (95% CI, 0.02-0.11). For boys, similar associations were observed for activity across the week 0.07 (95% CI, 0.03-0.11), during weekday schooltime 0.08 (95% CI, 0.04-0.12), and weekday out-of-school time 0.07 (95% CI, 0.03-0.11), but not the weekend 0.01 (95% CI, -0.03-0.05). For both girls and boys, associations were attenuated below significance after adjusting for baseline wellbeing. CONCLUSIONS: This longitudinal analysis showed positive associations between physical activity and later mental wellbeing in both male and female adolescents across most time segments. Higher physical activity throughout the week may be associated with better mental wellbeing in the adolescent population. Further research is required to understand determinants of change in wellbeing over time. TRIAL REGISTRATION: Registration Number: ISRCTN31583496. Registered: 18/02/2014.


Assuntos
Exercício Físico , Movimento , Humanos , Adolescente , Feminino , Masculino , Instituições Acadêmicas
4.
Brain Behav Evol ; 99(3): 123-143, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38569487

RESUMO

INTRODUCTION: Transitions in temporal niche have occurred many times over the course of mammalian evolution. These are associated with changes in sensory stimuli available to animals, particularly with visual cues, because levels of light are so much higher during the day than at night. This relationship between temporal niche and available sensory stimuli elicits the expectation that evolutionary transitions between diurnal and nocturnal lifestyles will be accompanied by modifications of sensory systems that optimize the ability of animals to receive, process, and react to important stimuli in the environment. METHODS: This study examines the influence of temporal niche on investment in sensory brain tissue of 13 rodent species (five diurnal; eight nocturnal). Animals were euthanized and the brains immediately frozen on dry ice; olfactory bulbs were subsequently dissected and weighed, and the remaining brain was weighed, sectioned, and stained. Stereo Investigator was used to calculate volumes of four sensory regions that function in processing visual (lateral geniculate nucleus, superior colliculus) and auditory (medial geniculate nucleus, inferior colliculus) information. A phylogenetic framework was used to assess the influence of temporal niche on the relative sizes of these brain structures and of olfactory bulb weights. RESULTS: Compared to nocturnal species, diurnal species had larger visual regions, whereas nocturnal species had larger olfactory bulbs than their diurnal counterparts. Of the two auditory structures examined, one (medial geniculate nucleus) was larger in diurnal species, while the other (inferior colliculus) did not differ significantly with temporal niche. CONCLUSION: Our results indicate a possible indirect association between temporal niche and auditory investment and suggest probable trade-offs of investment between olfactory and visual areas of the brain, with diurnal species investing more in processing visual information and nocturnal species investing more in processing olfactory information.


Assuntos
Ritmo Circadiano , Bulbo Olfatório , Roedores , Animais , Roedores/fisiologia , Bulbo Olfatório/fisiologia , Ritmo Circadiano/fisiologia , Encéfalo/fisiologia , Especificidade da Espécie , Corpos Geniculados/fisiologia , Filogenia , Colículos Superiores/fisiologia , Tamanho do Órgão/fisiologia , Evolução Biológica
5.
Scand J Med Sci Sports ; 34(5): e14649, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38757450

RESUMO

While physical activity (PA) is understood to promote vascular health, little is known about whether the daily and weekly patterns of PA accumulation associate with vascular health. Accelerometer-derived (activPAL3) 6- or 7-day stepping was analyzed for 6430 participants in The Maastricht Study (50.4% women; 22.4% Type 2 diabetes mellitus (T2DM)). Multivariable regression models examined associations between stepping metrics (average step count, and time spent slower and faster paced stepping) with arterial stiffness (measured as carotid-femoral pulse wave velocity (cfPWV)), and several indices of microvascular health (heat-induced skin hyperemia, retinal vessel reactivity and diameter), adjusting for confounders and moderators. PA pattern metrics were added to the regression models to identify associations with vascular health beyond that of stepping metrics. Analyses were stratified by T2DM status if an interaction effect was present. Average step count and time spent faster paced stepping was associated with better vascular health, and the association was stronger in those with compared to those without T2DM. In fully adjusted models a higher step count inter-daily stability was associated with a higher (worse) cfPWV in those without T2DM (std ß = 0.04, p = 0.007) and retinal venular diameter in the whole cohort (std ß = 0.07, p = 0.002). A higher within-day variability in faster paced stepping was associated with a lower (worse) heat-induced skin hyperemia in those with T2DM (std ß = -0.31, p = 0.008). Above and beyond PA volume, the daily and weekly patterns in which PA was accumulated were additionally associated with improved macro- and microvascular health, which may have implications for the prevention of vascular disease.


Assuntos
Diabetes Mellitus Tipo 2 , Exercício Físico , Rigidez Vascular , Humanos , Feminino , Rigidez Vascular/fisiologia , Masculino , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/fisiopatologia , Exercício Físico/fisiologia , Idoso , Hiperemia/fisiopatologia , Acelerometria , Velocidade da Onda de Pulso Carótido-Femoral , Adulto , Análise de Onda de Pulso , Vasos Retinianos/fisiologia
6.
BMC Public Health ; 24(1): 1754, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956531

RESUMO

BACKGROUND: This study aimed to investigate the relationships between accelerometer-measured physical activity (PA) and sedentary behaviour (SB) with physical function (PF) among older Chinese women in the community. METHODS: The present study comprised 1,113 community-dwelling older females, with an average age of 65 ± 2 years. We employed a linear regression analysis to investigate the relationship between patterns of PA and SB with PF. PA variables consisted of total PA time, bouted PA time (a continuous PA that lasts equal to or more than 10 min), and sporadic PA time (a continuous PA that lasts less than 10 min). SB variables included total SB time, 30-min bout of SB (a continuous SB that lasts equal to or more than 30 min), and 60-min bout of SB (a continuous SB that lasts equal to or more than 60 min). PF variables comprised handgrip strength (HGS), one-legged stance test with eyes closed (OLSTEC), usual walking speed (UWS), maximum walking speed (MWS) and chair-stand time (CT). To explore the joint effects of moderate-to-vigorous-intensity PA (MVPA) and SB on PF, we divided the duration of SB and MVPA participation in older women into different combinations: low MVPA & high SB, low MVPA & low SB, high MVPA & high SB, high MVPA & low SB. RESULTS: The study revealed a significant association between 30-min bout of SB and CT, which remained after adjusting for total MVPA time (P = 0.021). Both total MVPA and bouted MVPA were found to be positively associated with better UWS, MWS, CT, and PF Z-score. When the combination of low MVPA & high SB was used as a reference, the regression coefficients for PF ascended by 1.32 (P < 0.001) in the high MVPA & high SB group and by 1.13 (P < 0.001) in the high MVPA & low SB group. CONCLUSIONS: A significant association was observed between poorer lower limb function and prolonged, uninterrupted SB in older women, rather than with the total SB time. Concurrently, the insufficient engagement in MVPA may also be a crucial factor contributing to poorer PF in older women. Engaging in longer durations and higher intensity of PA, such as bouts of MVPA lasting a minimum of 10 min or longer, may contribute to better PF.


Assuntos
Acelerometria , Exercício Físico , Comportamento Sedentário , Humanos , Feminino , Estudos Transversais , Idoso , Exercício Físico/fisiologia , Pessoa de Meia-Idade , Vida Independente , China
7.
BMC Public Health ; 24(1): 1254, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714982

RESUMO

BACKGROUND: Depression is a global burden with profound personal and economic consequences. Previous studies have reported that the amount of physical activity is associated with depression. However, the relationship between the temporal patterns of physical activity and depressive symptoms is poorly understood. In this exploratory study, we hypothesize that a particular temporal pattern of daily physical activity could be associated with depressive symptoms and might be a better marker than the total amount of physical activity. METHODS: To address the hypothesis, we investigated the association between depressive symptoms and daily dominant activity behaviors based on 24-h temporal patterns of physical activity. We conducted a cross-sectional study on NHANES 2011-2012 data collected from the noninstitutionalized civilian resident population of the United States. The number of participants that had the whole set of physical activity data collected by the accelerometer is 6613. Among 6613 participants, 4242 participants had complete demography and Patient Health Questionnaire-9 (PHQ-9) questionnaire, a tool to quantify depressive symptoms. The association between activity-count behaviors and depressive symptoms was analyzed using multivariable logistic regression to adjust for confounding factors in sequential models. RESULTS: We identified four physical activity-count behaviors based on five physical activity-counting patterns classified by unsupervised machine learning. Regarding PHQ-9 scores, we found that evening dominant behavior was positively associated with depressive symptoms compared to morning dominant behavior as the control group. CONCLUSIONS: Our results might contribute to monitoring and identifying individuals with latent depressive symptoms, emphasizing the importance of nuanced activity patterns and their probability of assessing depressive symptoms effectively.


Assuntos
Depressão , Exercício Físico , Aprendizado de Máquina , Humanos , Estudos Transversais , Masculino , Feminino , Exercício Físico/psicologia , Depressão/epidemiologia , Pessoa de Meia-Idade , Adulto , Estados Unidos/epidemiologia , Big Data , Inquéritos Nutricionais , Fatores de Tempo , Acelerometria , Idoso
8.
Eur J Appl Physiol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874620

RESUMO

BACKGROUND: The effect of differences in daily physical activity patterns on blood lipids has not been determined. This study examines the effects of the differences in free-living daily physical activity patterns (amount and intensity) on blood lipid levels in older adults. METHODS: This cross-sectional study included 51 older participants (71.8 ± 0.6 years, men = 8, women = 43). A triaxial accelerometer was used to assess physical activity patterns. The time from awakening to bedtime for each participant was used for group classification based on the amount (number of steps) and intensity (moderate-to-vigorous physical activity, MVPA) of physical activity. The morning step group (M Step) was defined as those who took more steps in the morning, and the afternoon step group (A Step) was defined as those who took more steps in the afternoon. The same method was used for MVPA (morning MVPA: M MVPA; afternoon MVPA: A MVPA). Blood samples were collected at the start of the study to determine blood lipid levels. RESULTS: Number of steps taken showed a trend toward lower low-density lipoprotein cholesterol (LDL-C) levels in the M Step group compared with the A Step group. The LDL/high-density lipoprotein (HDL) ratio was significantly lower in the M Step group than the A Step group (p < 0.05). The M MVPA group also had higher HDL-C levels and significantly lower LDL/HDL ratios than the A MVPA group (p < 0.05). CONCLUSIONS: These results suggest that compared with afternoon physical activity, daily morning physical activity (amount and intensity) is more effective in improving blood lipid levels.

9.
J Fish Biol ; 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39279054

RESUMO

The metabolic rate of a freely moving fish (routine metabolic rate) is tightly coupled with volitional movement (spontaneous activity), both of which commonly show strong daily cycles linked to the species-specific diel activity pattern. Mummichog (Fundulus heteroclitus), an important estuarine fish in the north western Atlantic Ocean, are historically reported as diurnal (i.e., more active during daylight). Our recent laboratory studies on a Bay of Fundy population, however, showed a free-running (i.e., similarly active daytime and night-time) or even nocturnal (i.e., more active at night-time) diel activity pattern. In the laboratory, near-infrared (NIR) illumination is commonly used with a NIR-sensitive camera to visualize fish activity across the light-dark periods of the day. Because NIR light is close to the visible light spectrum and certain fishes show sensitivity to NIR, the use of NIR with mummichog possibly could disturb the animals and obscure the identification of their true diel activity pattern. We aimed to determine if NIR illumination (940 nm wavelength) influences the diel activity pattern of mummichog. We used measurements of routine metabolic rate (oxygen consumption rate, MO2) as a proxy for activity, as evaluating the effect of NIR requires treatments where NIR lights are off, which precludes visualization and direct assessment of fish activity at night-time. We measured routine MO2 of mummichogs over 6 days, exposed to either NIR off-on-off (2 days for each off or on period) or the opposite sequence of NIR on-off-on (to control for time-dependent effects). NIR lights did not influence the diel cycle of routine MO2, and activity by proxy, in mummichog. Thus, NIR illumination is a suitable method to visualize mummichog during light-dark diel cycles. Routine MO2, and presumably activity, was similar or higher during night-time periods compared to daytime periods, confirming a free-running or nocturnal activity pattern for at least certain populations of mummichog.

10.
Proc Biol Sci ; 290(1999): 20230529, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37221845

RESUMO

Deforestation is a major contributor to biodiversity loss, yet the impact of forest loss on daily microclimate variability and its implications for species with different daily activity patterns remain poorly understood. Using a recently developed microclimate model, we investigated the effects of deforestation on the daily temperature range (DTR) in low-elevation tropical regions and high-elevation temperate regions. Our results show that deforestation substantially increases DTR in these areas, suggesting a potential impact on species interactions. To test this hypothesis, we studied the competitive interactions between nocturnal burying beetles and all-day-active blowfly maggots in forested and deforested habitats in Taiwan. We show that deforestation leads to increased DTR at higher elevations, which enhances the competitiveness of blowfly maggots during the day and leads to a higher failure rate of carcass burial by the beetles at night. Thus, deforestation-induced temperature variability not only modulates exploitative competition between species with different daily activity patterns, but also likely exacerbates the negative impacts of climate change on nocturnal organisms. In order to limit potential adverse effects on species interactions and their ecological functions, our study highlights the need to protect forests, especially in areas where deforestation can greatly alter temperature variability.


Assuntos
Biodiversidade , Besouros , Animais , Temperatura , Mudança Climática , Febre , Larva
11.
Am J Primatol ; 85(8): e23521, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37254265

RESUMO

Measuring glucocorticoids is one of the most reliable and widely used techniques to monitor stress responses, however invasive techniques to collect plasma samples may not be applicable for wild populations. Monitoring excreted glucocorticoids is an effective noninvasive technique that researchers have used increasingly over the past two decades, and it has allowed the investigation of glucocorticoids in a variety of species with a range of activity patterns. Many species exhibit predictable circadian patterns of glucocorticoid secretion in accordance with their daily activity pattern. There remains a gap in our understanding of how excreted glucocorticoid metabolites vary throughout the day and across species, despite the utility of this information when developing sampling protocols and analyzing data. We investigated circadian patterns of glucocorticoid excretion in a cathemeral primate species, Eulemur rubriventer (red-bellied lemur), in Ranomafana National Park, Madagascar. We collected fecal samples from 10 individuals throughout the day and analyzed fecal glucocorticoid levels across three time points (Early, Midday, and Late), and again across two time points (Morning and Afternoon). We also investigated whether activity pattern, sex (as a control variable), and other traits associated with gut passage rate (diet, body mass) could help predict the presence and timing of circadian patterns of fecal glucocorticoid metabolites across mammal species. We found that fecal glucocorticoid metabolite levels in E. rubriventer fluctuate throughout the day, with lowest levels in the morning and peak levels in the afternoon. None of the variables that we tested predicted whether daily fecal glucocorticoid metabolites changed significantly throughout the day, nor when levels were likely to peak, across species. We stress the importance of controlling for sampling time and reporting these results as standard practice in studies of fecal glucocorticoid metabolites.


Assuntos
Lemur , Lemuridae , Animais , Glucocorticoides , Lemur/fisiologia , Primatas , Madagáscar , Fezes , Mamíferos
12.
Ecol Appl ; 32(7): e2644, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35471769

RESUMO

Mammalian communities inhabiting temperate grasslands are of conservation concern globally, especially in Central Asia, where livestock numbers have dramatically increased in recent decades, leading to overgrazing and land-use change. Yet, how this pervasive presence of livestock herds affects the community of wild mammals remains largely unstudied. We used systematic camera trapping at 216 sites across remote, mountainous areas of the Mongolian Altai Mountains to assess the spatial and temporal patterns of occurrence and the interspecific relationships within a mammalian community that includes different categories of livestock. By adopting a recently proposed multispecies occupancy model that incorporates interspecific correlation in occupancy, we found several statistically strong correlations in occupancy among species pairs, with the majority involving livestock. The sign of such associations was markedly species-dependent, with larger wild species of conservation concern, namely, snow leopard and Siberian ibex, avoiding livestock presence. As predicted, we found evidence of a positive correlation in occupancy between predators and their respective main prey. Contrary to our expectations, a number of intraguild species pairs also showed positive co-occurrence, with no evidence of spatiotemporal niche partitioning. Overall, our study suggests that livestock encroaching into protected areas influences the whole local community of wild mammals. Though pastoralism has coexisted with wildlife for millennia in central Asian grasslands, our findings suggest that policies and practices to decrease the pressure of livestock husbandry on wildlife are needed, with special attention on large species, such as the snow leopard and its wild prey, which seem to be particularly sensitive to this pervasive livestock presence.


Assuntos
Gado , Panthera , Animais , Animais Selvagens , Conservação dos Recursos Naturais
13.
Scand J Med Sci Sports ; 32(1): 18-44, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34695249

RESUMO

Physical activity (PA) is a complex human behavior, which implies that multiple dimensions need to be taken into account in order to reveal a complete picture of the PA behavior profile of an individual. This scoping review aimed to map advanced analytical methods and their summary variables, hereinafter referred to as wearable-specific indicators of PA behavior (WIPAB), used to assess PA behavior. The strengths and limitations of those indicators as well as potential associations with certain health-related factors were also investigated. Three databases (MEDLINE, Embase, and Web of Science) were screened for articles published in English between January 2010 and April 2020. Articles, which assessed the PA behavior, gathered objective measures of PA using tri-axial accelerometers, and investigated WIPAB, were selected. All studies reporting WIPAB in the context of PA monitoring were synthesized and presented in four summary tables: study characteristics, details of the WIPAB, strengths, and limitations, and measures of association between those indicators and health-related factors. In total, 7247 records were identified, of which 24 articles were included after assessing titles, abstracts, and full texts. Thirteen WIPAB were identified, which can be classified into three different categories specifically focusing on (1) the activity intensity distribution, (2) activity accumulation, and (3) the temporal correlation and regularity of the acceleration signal. Only five of the thirteen WIPAB identified in this review have been used in the literature so far to investigate the relationship between PA behavior and health, while they may provide useful additional information to the conventional PA variables.


Assuntos
Atividade Motora , Envio de Mensagens de Texto , Acelerometria , Exercício Físico , Humanos , Fatores de Tempo
14.
Am J Primatol ; 84(9): e23423, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35848355

RESUMO

Recently, several diurnal nonhuman anthropoids have been identified displaying varying degrees of nocturnal activity, which can be influenced by activity "masking effects"-external events or conditions that suppress or trigger activity, temporarily altering normal activity patterns. Environmental masking characteristics include nocturnal temperature, rainfall, cloud cover, and moon brightness. Similarly, other ecological characteristics, including proximity to humans and predators and daytime activity, may also trigger or suppress nocturnal activity. Understanding the effects of external conditions on activity patterns is pertinent to effective species conservation. We investigated the presence of nocturnal activity and the influence of masking effects on the level of nocturnal activity displayed by wild proboscis monkeys (Nasalis larvatus) in Sabah, Malaysian Borneo. Dual-axis accelerometers were attached by collar to six male proboscis monkeys from different one-male, multi-female groups to record activity continuously (165-401 days each). We measured the monkeys' nocturnal and diurnal activity levels and investigated the effects of seven potential masking effects. Nocturnal activity was much lower than diurnal activity. Still, proboscis monkeys did display varying levels of nocturnal activity. Generalized linear mixed models identified higher nocturnal activity in the study individuals during nights with cooler temperatures, higher rainfall, and after higher diurnal activity. These three masking effects affected nocturnal activity levels during the observation period that informed our model, although they did not predict nocturnal activity outside of this period. While the generalizability of these results remains uncertain, this study highlights the utility of accelerometers in identifying activity patterns and masking effects that create variability in these patterns.


Assuntos
Presbytini , Animais , Ritmo Circadiano , Feminino , Haplorrinos , Humanos , Malásia , Masculino , Lua , Temperatura
15.
West Afr J Med ; 39(2): 119-126, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35277954

RESUMO

BACKGROUND: The prevalence of adolescent obesity is rising in all parts of the world, but only very few studies have considered factors influencing obesity among Nigerian adolescents. Therefore, this study aimed to determine the prevalence of obesity and its association with sociodemographic profile, lifestyle factors, dietary patterns, and physical activity patterns among in-school adolescents in Southwest Nigeria. METHODS: A total sample size of 400 in-school adolescents were selected through a multi-stage sampling technique from secondary schools in Ile-Ife. The dietary patterns were assessed using a 92-item FFQ, while the activity patterns were assessed using the physical activity questionnaire for older children and adolescents. Data were analyzed using IBM SPSS. RESULTS: There were 211 (52.8%) males and 189 (47.3%) females, with mean ages of 14.8 ± 2.1 and 14.4 ± 1.9 years, respectively. The prevalence of overweight/obesity was 12.8%. The associated factors were age, sex, class, the number of children in the family, birth orders and the dietary pattern dominated by starchy foods, roots and tubers (p<0.05). CONCLUSION: The prevalence of overweight/obesity was relatively high among the respondents. It was associated with age, the number of children in the family, and adolescents' birth order. WAJM 2022; 39(2): 119-126.


CONTEXTE: La prévalence de l'obésité chez les adolescents augmente dans toutes les régions du monde, mais très peu d'études ont facteurs considérés comme influençant l'obésité chez les adolescents Nigérians. Par conséquent, cette étude visait à déterminer le prévalence de l'obésité et son association avec le profil sociodémographique, les facteurs de style de vie, les habitudes alimentaires et les habitudes d'activité physique chez les adolescents scolarisés dans Sud-ouest du Nigeria. MÉTHODES: Un échantillon total de 400 adolescents scolarisés ont été sélectionnés par une technique d'échantillonnage en plusieurs étapes à partir de écoles secondaires d'Ile-Ife. Les habitudes alimentaires ont été évaluées à l'aide d'un questionnaire FFQ de 92 items, tandis que les habitudes d'activité ont été évaluées à l'aide du questionnaire sur l'activité physique pour les enfants plus âgés et les adolescents. Les données ont été analysées à l'aide d'IBM SPSS. RÉSULTATS: Il y avait 211 hommes (52.8 %) et 189 hommes (47.3 %) femelles, avec des âges moyens de 14.8 ± 2.1 et 14.4 ±1.9 ans, respectivement. La prévalence du surpoids / obésité était de 12.8%. Les facteurs associés étaient l'âge, le sexe, la classe, le nombre de enfants dans la famille, ordres de naissance et régime alimentaire dominé par les féculents, les racines et les tubercules (p <0.05). CONCLUSION: La prévalence du surpoids / de l'obésité était relativement élevé parmi les répondants. Il était associé à l'âge, le nombre d'enfants dans la famille et l'ordre de naissance des adolescents.


Assuntos
Obesidade Infantil , Adolescente , Índice de Massa Corporal , Criança , Exercício Físico , Feminino , Humanos , Estilo de Vida , Masculino , Nigéria/epidemiologia , Obesidade Infantil/epidemiologia , Prevalência
16.
J Neurophysiol ; 125(4): 1289-1306, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33502956

RESUMO

The pre-Bötzinger complex (preBötC), located within the ventral respiratory column, produces inspiratory bursts in varying degrees of synchronization/amplitude. This wide range of population burst patterns reflects the flexibility of the preBötC neurons, which is expressed in variations in the onset/offset times of their activations and their activity during the population bursts, with respiratory neurons exhibiting a large cycle-to-cycle timing jitter both at the population activity onset and at the population activity peak, suggesting that respiratory neurons are stochastically activated before and during the inspiratory bursts. However, it is still unknown whether this stochasticity is maintained while evaluating the coactivity of respiratory neuronal ensembles. Moreover, the preBötC topology also remains unknown. In this study, by simultaneously recording tens of preBötC neurons and using coactivation analysis during the inspiratory periods, we found that the preBötC has a scale-free configuration (mixture of not many highly connected nodes, hubs, with abundant poorly connected elements) exhibiting the rich-club phenomenon (hubs more likely interconnected with each other). PreBötC neurons also produce multineuronal activity patterns (MAPs) that are highly stable and change during the hypoxia-induced reconfiguration. Moreover, preBötC contains a coactivating core network shared by all its MAPs. Finally, we found a distinctive pattern of sequential coactivation of core network neurons at the beginning of the inspiratory periods, indicating that, when evaluated at the multicellular level, the coactivation of respiratory neurons seems not to be stochastic.NEW & NOTEWORTHY By means of multielectrode recordings of preBötC neurons, we evaluated their configuration in normoxia and hypoxia, finding that the preBötC exhibits a scale-free configuration with a rich-club phenomenon. preBötC neurons produce multineuronal activity patterns that are highly stable but change during hypoxia. The preBötC contains a coactivating core network that exhibit a distinctive pattern of coactivation at the beginning of inspirations. These results reveal some network basis of inspiratory rhythm generation and its reconfiguration during hypoxia.


Assuntos
Fenômenos Eletrofisiológicos/fisiologia , Hipóxia/fisiopatologia , Interneurônios/fisiologia , Bulbo/fisiologia , Rede Nervosa/fisiologia , Centro Respiratório/fisiologia , Taxa Respiratória/fisiologia , Animais , Feminino , Masculino , Camundongos
17.
Pediatr Cardiol ; 42(4): 774-783, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33523288

RESUMO

Previous research in children and adolescents with congenital heart defects presents contradictory findings concerning their physical activity (PA) level, due to methodological limitations in the PA assessment. The aim of the present cross-sectional study was to compare PA in children and adolescents treated for valvular aortic stenosis with healthy controls using an improved accelerometer method. Seven-day accelerometer data were collected from the hip in a national Swedish sample of 46 patients 6-18 years old treated for valvular aortic stenosis and 44 healthy controls matched for age, gender, geography, and measurement period. Sports participation was self-reported. Accelerometer data were processed with the new improved Frequency Extended Method and with the traditional ActiGraph method for comparison. A high-resolution PA intensity spectrum was investigated as well as traditional crude PA intensity categories. Children treated for aortic stenosis had a pattern of less PA in the highest intensity spectra and had more sedentary time, while the adolescent patients tended to be less physically active in higher intensities overall and with less sedentary time, compared to the controls. These patterns were evident using the Frequency Extended Method with the detailed PA intensity spectrum, but not to the same degree using the ActiGraph method and traditional crude PA intensity categories. Patients reported less sports participation than their controls in both age-groups. Specific differences in PA patterns were revealed using the Frequency Extended Method with the high-resolution PA intensity spectrum in Swedish children and adolescents treated for valvular aortic stenosis.


Assuntos
Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/terapia , Exercício Físico , Acelerometria/métodos , Adolescente , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Nível de Saúde , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/terapia , Humanos , Masculino , Comportamento Sedentário , Autorrelato , Esportes
18.
Sensors (Basel) ; 21(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833591

RESUMO

Smartphones as ubiquitous gadgets are rapidly becoming more intelligent and context-aware as sensing, networking, and processing capabilities advance. These devices provide users with a comprehensive platform to undertake activities such as socializing, communicating, sending and receiving e-mails, and storing and accessing personal data at any time and from any location. Nowadays, smartphones are used to store a multitude of private and sensitive data including bank account information, personal identifiers, account passwords and credit card information. Many users remain permanently signed in and, as a result, their mobile devices are vulnerable to security and privacy risks through assaults by criminals. Passcodes, PINs, pattern locks, facial verification, and fingerprint scans are all susceptible to various assaults including smudge attacks, side-channel attacks, and shoulder-surfing attacks. To solve these issues, this research introduces a new continuous authentication framework called DeepAuthen, which identifies smartphone users based on their physical activity patterns as measured by the accelerometer, gyroscope, and magnetometer sensors on their smartphone. We conducted a series of tests on user authentication using several deep learning classifiers, including our proposed deep learning network termed DeepConvLSTM on the three benchmark datasets UCI-HAR, WISDM-HARB and HMOG. Results demonstrated that combining various motion sensor data obtained the highest accuracy and energy efficiency ratio (EER) values for binary classification. We also conducted a thorough examination of the continuous authentication outcomes, and the results supported the efficacy of our framework.


Assuntos
Aprendizado Profundo , Computadores de Mão , Exercício Físico , Privacidade , Smartphone
19.
Int J Mol Sci ; 22(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205237

RESUMO

A substantial proportion of neurons undergoes programmed cell death (apoptosis) during early development. This process is attenuated by increased levels of neuronal activity and enhanced by suppression of activity. To uncover whether the mere level of activity or also the temporal structure of electrical activity affects neuronal death rates, we optogenetically controlled spontaneous activity of synaptically-isolated neurons in developing cortical cultures. Our results demonstrate that action potential firing of primary cortical neurons promotes neuronal survival throughout development. Chronic patterned optogenetic stimulation allowed to effectively modulate the firing pattern of single neurons in the absence of synaptic inputs while maintaining stable overall activity levels. Replacing the burst firing pattern with a non-physiological, single pulse pattern significantly increased cell death rates as compared to physiological burst stimulation. Furthermore, physiological burst stimulation led to an elevated peak in intracellular calcium and an increase in the expression level of classical activity-dependent targets but also decreased Bax/BCL-2 expression ratio and reduced caspase 3/7 activity. In summary, these results demonstrate at the single-cell level that the temporal pattern of action potentials is critical for neuronal survival versus cell death fate during cortical development, besides the pro-survival effect of action potential firing per se.


Assuntos
Neocórtex/citologia , Neurônios/fisiologia , Optogenética , Potenciais de Ação , Animais , Células Cultivadas , Proteínas Luminescentes , Camundongos , Técnicas de Patch-Clamp , Proteína Vermelha Fluorescente
20.
BMC Ecol ; 20(1): 4, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31918698

RESUMO

BACKGROUND: Wild boars (Sus scrofa L.) are globally widely distributed, and their populations have increased in Europe during recent decades. Encounters between humans and wild boars are rare because of the predominantly nocturnal lifestyle of the latter, and wild boar management by hunting is a challenging task. Animal activity patterns are important for understanding the behaviour of a species. However, knowledge of detailed temporal patterns and an understanding of the drivers of wild boar activity at a fine temporal scale are lacking. Of special relevance for human-wild boar interactions (e.g., encounters, conflicts, and management) is the question of whether nocturnal activity depends on anthropogenic factors and, particularly, how local hunting regimes may affect activity patterns. We used GPS telemetry and acceleration measurements to shed light on this part of wild boar behaviour, observing 34 animals in Central Europe. Animals were tracked along a gradient of hunting pressure from hunting-free areas to areas with low or high hunting pressure. Fitted generalised additive models allowed predicting the probability of active behaviour under differing disturbance regimes precisely to day of year and time of day. RESULTS: The wild boars were predominantly nocturnal, with peak activity at approximately midnight. However, the data showed increased activity during daylight for wild boars that used no-hunting zones or reduced-hunting zones. Large areas with low disturbance levels promoted activity during daylight more than smaller areas with an intermediate disturbance regime. High air temperatures and locations within forests reduced the probability of active behaviour, whereas proximity to tracks used for forestry or agriculture was accompanied by a higher probability of activity. CONCLUSIONS: We conclude that wild boars flexibly adjust their activity to their local environmental conditions, considering disturbances at the scale of long-term home ranges as well as actual small-scale landscape quality. Entire wild boar home ranges should be covered in the delineation of reserves intending to stimulate activity during daylight.


Assuntos
Agricultura , Sus scrofa , Animais , Europa (Continente) , Humanos , Suínos
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