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Previous research on affordance perception has shown that elite athletes can relate the environmental features to their motor abilities to detect the opportunities for action. In playing badminton doubles, experienced players can often anticipate whether a flick serve will go out-of-bounds or not. A field study was performed to examine if such an ability was associated with a developed affordance perception. Twenty-two players with and without badminton playing experience were asked to play a receiver on court to judge without looking back whether a flick serve was out-of-bounds in both standing and retreating conditions. Forty flick serves were randomly delivered to either inner or outer rear corner of the receiver's box and land adjacent to the back service line. Each player's ability to reach high and retreat backward with a racquet was assessed on court. The results showed that predictions were better in the inner direction than the outer direction, but experienced players were more sensitive and conservative overall. Playing experience appeared to be a consistent predictor for judgment accuracy. In identifying the affordance information that could have been utilized by players for accurate predictions, only experienced players demonstrated the ability to utilize both body-scaled and action-scaled affordances effectively and reliably for better predictions in both standing and retreating conditions.
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Juicio , Deportes de Raqueta , Humanos , Masculino , Adulto Joven , Femenino , Adulto , Rendimiento Atlético/fisiología , Adolescente , Percepción Visual/fisiologíaRESUMEN
Debate exists on life-course adrenocortical zonal function trajectories. Rapid, phasic blood steroid concentration changes, such as circadian rhythms and acute stress responses, complicate quantification. To avoid pitfalls and account for life-stage changes in adrenocortical activity indices, we quantified zonae fasciculata (ZF) and reticularis (ZR) across the life-course, by immunohistochemistry of key regulatory and functional proteins. In 28 female baboon adrenals (7.5-22.1 years), we quantified 12 key proteins involved in cell metabolism, division, proliferation, steroidogenesis (including steroid acute regulatory protein, StAR), oxidative stress, and glucocorticoid and mitochondrial function. Life-course abundance of ten ZF proteins decreased with age. Cell cycle inhibitor and oxidative stress markers increased. Seven of the 12 proteins changed in the same direction for ZR and ZF. Importantly, ZF StAR decreased, while ZR StAR was unchanged. Findings indicate ZF function decreased, and less markedly ZR function, with age. Causes and aging consequences of these changes remain to be determined.
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Zona Fascicular , Zona Reticular , Femenino , Humanos , Zona Reticular/metabolismo , Zona Fascicular/metabolismo , Acontecimientos que Cambian la Vida , Esteroides/metabolismoRESUMEN
The steroids corticosterone and dehydroepiandrosterone (DHEA) perform multiple life course functions. Rodent life-course circulating corticosterone and DHEA trajectories are unknown. We studied life course basal corticosterone and DHEA in offspring of rats fed protein-restricted (10% protein, R) or control (20% protein, C), pregnancy diet first letter, and/or lactation second letter, producing four offspring groups-CC, RR, CR, and RC. We hypothesize that 1. maternal diet programs are sexually dimorphic, offspring life course steroid concentrations, and 2. an aging-related steroid will fall. Both changes differ with the plastic developmental period offspring experienced R, fetal life or postnatally, pre-weaning. Corticosterone was measured by radioimmunoassay and DHEA by ELISA. Steroid trajectories were evaluated by quadratic analysis. Female corticosterone was higher than male in all groups. Male and female corticosterone were highest in RR, peaked at 450 days, and fell thereafter. DHEA declined with aging in all-male groups. DHEA: corticosterone fell in three male groups but increased in all-female groups with age. In conclusion, life course and sexually dimorphic steroid developmental programming-aging interactions may explain differences in steroid studies at different life stages and between colonies experiencing different early-life programming. These data support our hypotheses of sex and programming influences and aging-related fall in rat life course serum steroids. Life course studies should address developmental programming-aging interactions.
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Corticosterona , Dieta con Restricción de Proteínas , Embarazo , Ratas , Animales , Femenino , Masculino , Ratas Wistar , Envejecimiento/metabolismo , DeshidroepiandrosteronaRESUMEN
We measured walking speed in baboons (67 female, 36 male; 5-22 years) to develop regression formulas to predict biological age. The final model strongly predicted age from just speed and sex. Walking speed is a valuable baboon aging biomarker. We present the first male speed data in a nonhuman primate.
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Envejecimiento , Velocidad al Caminar , Animales , Femenino , Masculino , PapioRESUMEN
Older adults are frequently cited as an at-risk population for vitamin D deficiency that may in part be due to decreased cutaneous synthesis, a potentially important source of cholecalciferol (vitamin D3). Previous studies found that cutaneous D3 production declines with age; however, most studies have been conducted ex vivo or in the photobiology lab. The purpose of this study was to characterize the response of vitamin D metabolites following a 30-min bout of sun exposure (15-min each to the dorsal and ventral sides) at close to solar noon in younger and older adults. METHODS: 30 healthy individuals with skin type II/III were recruited; a younger cohort, aged 20-37 (n = 18) and an older cohort (n = 12), age 51-69 years. Exposure was at outer limits of sensible sun exposure designed to enhance vitamin D synthesis without increasing risk of photo ageing and non-melanoma skin cancer. Serum D3 concentration was measured at baseline, 24, 48 and 72 h post-exposure. Serum 25(OH)D was measured at baseline and 72 h post-exposure plus 168 h post-exposure in the older cohort. RESULTS: D3 increased in response to sun exposure (time effect; p = 0.002) with a trend for a difference in D3 between cohorts (time*group; p = 0.09). By regression modeling of continuous data, age accounted for 20% of the variation in D3 production. D3 production decreased by 13% per decade. Despite changes in D3, however, serum 25(OH)D did not change from baseline to 72 or 168 h post exposure (p > 0.10). CONCLUSIONS: Serum D3 concentration increased significantly in response to outdoor sun exposure in younger and older adults. While ageing may dampen cutaneous synthesis, sunlight exposure is still a significant source of vitamin D3.
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Factores de Edad , Colecalciferol/sangre , Luz Solar , Vitamina D/análogos & derivados , Vitamina D/biosíntesis , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Piel/metabolismo , Factores de Tiempo , Vitamina D/sangre , Deficiencia de Vitamina D/etiología , Adulto JovenRESUMEN
There are several different methods available for the determination of body fat composition. Two current methods requiring special instrumentation are magnetic resonance imaging (MRI) and dual energy x-ray absorptiometry (DXA). The use of these techniques is very limited despite desirable properties, due to their high costs. Dissection of all fat depots (DF) requires no special instrumentation and allows examination and evaluation of each fat depot in more detail. MRI, DXA, and DF each have their unique advantages and disadvantages when they are applied to animal models. Most studies have determined body fat in young animals, and few studies have been performed in aging models. The aim of this study was to compare MRI, DXA, and DF data in offspring (F1) of mothers fed with control and high-fat diet. We studied rats that varied by age, sex, and maternal diet. The relationships between the three methods were determined via linear regression methods (using log-transformed values to accommodate relativity in the relationships), incorporating when useful age, sex, or diet of the animal. We conclude that the three methods are comparable for measuring body fat, but that direct equivalence gets masked by age, sex, and sometimes dietary group. Depending on the equipment available, the budget of the laboratory, and the nature of the research questions, different approaches may often suggest themselves as the best one.
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Tejido Adiposo/diagnóstico por imagen , Composición Corporal , Absorciometría de Fotón , Animales , Dieta Alta en Grasa , Disección , Femenino , Imagen por Resonancia Magnética , Masculino , Ratas , Ratas WistarRESUMEN
INTRODUCTION: Women threatening premature delivery receive synthetic glucocorticoids (sGC) to accelerate fetal lung maturation, reducing neonatal mortality and morbidity. Few investigations have explored potential long-term offspring side effects. We previously reported increased pericardial fat and liver lipids in 10-year-old (human equivalent 40 years) male baboons exposed to 3 antenatal sGC courses. We hypothesized middle-aged sGC male offspring show obesity-related morphometric changes. METHODS: Pregnant baboons received courses of 2 betamethasone injections (175 µg·kg-1·d-1 intramuscular) at 0.6, 0.64, and 0.68 gestation. At 10 to 12.5 years, we measured morphometrics and serum lipids in 5 sGC-exposed males and 10 age-matched controls. We determined whether morphometric parameters predicted amount of pericardial fat or lipids. Life-course serum lipids were measured in 25 males (7-23 years) providing normal regression formulas to compare sGC baboons' lipid biological and chronological age. RESULTS: Birth weights were similar. When studied, sGC-exposed males showed a steeper weight increase from 8 to 12 years and had increased waist and hip circumferences, neck and triceps skinfolds, and total and low-density lipoprotein cholesterol. Triceps skinfold correlated with apical and midventricular pericardial fat thickness, hip and waist circumferences with insulin. CONCLUSIONS: Triceps skinfold and waist and hip circumferences are useful biomarkers for identifying individuals at risk for obesity and metabolic dysregulation following fetal sGC exposure. Prenatal sGC exposure predisposes male offspring to internal adiposity, greater body size, and increased serum lipids. Results provide further evidence for developmental programming by fetal sGC exposure and call attention to potential emergence of adverse life-course effects.
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Envejecimiento , Betametasona/efectos adversos , Glucocorticoides/efectos adversos , Obesidad/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Adiposidad , Animales , Betametasona/administración & dosificación , Peso Corporal , Femenino , Glucocorticoides/administración & dosificación , Humanos , Masculino , Obesidad/fisiopatología , Papio , Fenotipo , EmbarazoRESUMEN
BACKGROUND: Non-human primate models of developmental programming by maternal obesity (MO) are needed for translation to human programming outcomes. We present baboon offspring (F1) morphometry, blood cortisol, and adrenocorticotropic hormone (ACTH) from 0.9 gestation to 0-2 years. METHODS: Control mothers ate chow; MO mothers ate high-fat high-energy diet pre-pregnancy through lactation. RESULTS: Maternal obesity mothers weighed more than controls pre-pregnancy. Maternal obesity gestational weight gain was lower with no correlation with fetal or placenta weights. At 0.9 gestation, MO and control F1 morphometry and ACTH were similar. MO-F1 0.9 gestation male cortisol was lower, rising slower from 0-2 years vs control-F1. At birth, male MO-F1 and control-F1 weights were similar, but growth from 0-2 years was steeper in MO-F1; newborn female MO-F1 weighed more than control-F1 but growth from 0-2 years was similar. ACTH did not change in either sex. CONCLUSIONS: Maternal obesity produced sexually dimorphic fetal and postnatal growth and hormonal phenotypes.
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Hormona Adrenocorticotrópica/sangre , Hidrocortisona/sangre , Obesidad Materna/complicaciones , Papio , Efectos Tardíos de la Exposición Prenatal/metabolismo , Animales , Animales Recién Nacidos/fisiología , Femenino , Feto/fisiopatología , Fenotipo , Embarazo , SueroRESUMEN
The World Health Organization recently recognized the Republic of Kosovo as one of the highest consumers per capita of antibiotics for human use among non-European Union Eastern European countries; however, data are limited regarding antimicrobial usage and antimicrobial resistance in the livestock sector for this recently formed country. The objective of this study was to conduct the first nationwide survey of antimicrobial resistance phenotypes in indicator bacteria collected from dairy farms in Kosovo. Composite fecal samples were collected from 52 farms located within all 7 administrative districts of Kosovo in the summer of 2014. Isolation and characterization of the indicator bacteria Escherichia coli (n = 165) and Enterococcus spp. (n = 153) from these samples was achieved by culturing on selective/differential media with and without select antibiotics, followed by MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry-based identification and antimicrobial susceptibility testing using the disk diffusion method. When no selective pressure was applied in culture-based isolation, the majority of E. coli and Enterococcus spp. collected were resistant to ≤1 of 16 and ≤2 of 12 antibiotics tested, respectively. In contrast, E. coli and Enterococcus spp. isolated using sub-minimum inhibitory concentrations of cefoxitin, ciprofloxacin, or erythromycin were typically resistant to at least one and often multiple antibiotic types, which primarily consisted of certain ß-lactams, quinolones, sulfonamides, phenicols, and tetracyclines for E. coli isolates and macrolides, tetracyclines, and rifamycins for enterococci isolates.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Animales , Industria Lechera , Enterococcus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Granjas , Heces/microbiología , Contaminación de Alimentos , Humanos , Kosovo , Encuestas y CuestionariosRESUMEN
OBJECTIVE: We evaluated how nighttime media use is associated with sleep behaviors in firstsemester college students, and variation by weight status. METHODS: In September 2016, first-semester college students (N = 114) completed surveys evaluating nighttime media usage (NMU) and sleep behaviors. Height, weight, and waist circumference were measured, and weight status was determined by body mass index. RESULTS: Students reported a mean sleep duration of 7.26 ± 0.93 hours. Only 33% (N = 38) reported sleeping at least 8 hours/night on average. Higher scores on the Pittsburgh Sleep Quality Index were correlated with reports of texting after bed (r = .199, p = .04). Total time in bed was correlated with texting in bed (r = .217, p = .026) and device-related sleep interruptions (r = .215, p = .028). Social media usage (r = 0.270, p = .005), mobile gaming (r = .208, p = .033), and texting (r = .293, p = .002) were correlated with sleep interruptions. NMU was positively correlated with weight and weight status. CONCLUSIONS: These results suggest NMU is associated with reduced sleep quality.
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Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Medios de Comunicación Sociales/estadística & datos numéricos , Estudiantes/psicología , Universidades , Adolescente , Índice de Masa Corporal , Femenino , Humanos , Masculino , Envío de Mensajes de Texto/estadística & datos numéricos , Juegos de Video/estadística & datos numéricos , Adulto JovenRESUMEN
Stressors that disrupt homeostasis advance aging. Glucocorticoids regulate multiple processes that determine the aging trajectory. Debate exists regarding life-course circulating glucocorticoid concentrations. Rodent and nonhuman primate studies indicate circulating glucocorticoids fall from early life. We measured fasting morning cortisol in 24 female baboons (6-21 years, human equivalent ~18-70). We also quantified hypothalamic paraventricular nuclear (PVN) arginine vasopressin (AVP), corticotropin-releasing hormone, steroid receptors, and pituitary proopiomelanocortin immunohistochemically in 14 of these females at 6-13 years. We identified significant age-related 1) linear fall in cortisol and PVN AVP from as early as 6 years; 2) increased PVN glucocorticoid and mineralocorticoid receptors; 3) increased PVN 11ß-hydroxysteroid dehydrogenase 1 and 2, regulators of local cortisol production, and 4) decreased pituitary proopiomelanocortin. Our data identify increased age-related negative feedback and local PVN cortisol production as potential mechanisms decreasing PVN drive to hypothalamo-pituitary-adrenal axis activity that result in the age-related circulating cortisol fall. Further studies are needed to determine whether the cortisol fall 1) causes aging, 2) protects by slowing aging, or 3) is an epiphenomenon unrelated to aging processes. We conclude that aging processes are best studied by linear life-course analysis beginning early in life.
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Envejecimiento/sangre , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Factores de Edad , Animales , Arginina Vasopresina/metabolismo , Biomarcadores/sangre , Ritmo Circadiano , Hormona Liberadora de Corticotropina/metabolismo , Retroalimentación Fisiológica , Femenino , Papio , Núcleo Hipotalámico Paraventricular/metabolismo , Proopiomelanocortina/metabolismo , Receptores de Esteroides/metabolismoRESUMEN
BACKGROUND: Walking speed is an important human aging biomarker. Baboons are valuable translational models for aging studies. Establishing whether walking speed is a good aging biomarker has value. We hypothesized there would be characteristic age-related decline in baboon walking speed. METHODS: We studied 33 female baboons aged 5-21 years. Walking speed was calculated by the time to walk between landmarks separated by known distances. A regression model was developed to describe the relationship between speed, age, and body weight. RESULTS: Speed negatively associated with age, a relationship enhanced by increased weight (P < 0.0005). For 16-kg animals, speed declined approximately 0.6 cm/s yearly. For each additional kilogram of weight, speed declined an additional 0.3 cm/s yearly. CONCLUSIONS: Baboon walking speed declines with age, an effect modulated by weight. Ease of measurement and strong age association make walking speed a valuable biomarker for aging research with this important experimental species.
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Envejecimiento/fisiología , Papio/fisiología , Caminata/fisiología , Animales , Femenino , Factores de TiempoRESUMEN
Identifying the ecological dynamics underlying human-wildlife conflicts is important for the management and conservation of wildlife populations. In landscapes still occupied by large carnivores, many ungulate prey species migrate seasonally, yet little empirical research has explored the relationship between carnivore distribution and ungulate migration strategy. In this study, we evaluate the influence of elk (Cervus elaphus) distribution and other landscape features on wolf (Canis lupus) habitat use in an area of chronic wolf-livestock conflict in the Greater Yellowstone Ecosystem, USA. Using three years of fine-scale wolf (n = 14) and elk (n = 81) movement data, we compared the seasonal habitat use of wolves in an area dominated by migratory elk with that of wolves in an adjacent area dominated by resident elk. Most migratory elk vacate the associated winter wolf territories each summer via a 40-60 km migration, whereas resident elk remain accessible to wolves year-round. We used a generalized linear model to compare the relative probability of wolf use as a function of GIS-based habitat covariates in the migratory and resident elk areas. Although wolves in both areas used elk-rich habitat all year, elk density in summer had a weaker influence on the habitat use of wolves in the migratory elk area than the resident elk area. Wolves employed a number of alternative strategies to cope with the departure of migratory elk. Wolves in the two areas also differed in their disposition toward roads. In winter, wolves in the migratory elk area used habitat close to roads, while wolves in the resident elk area avoided roads. In summer, wolves in the migratory elk area were indifferent to roads, while wolves in resident elk areas strongly avoided roads, presumably due to the location of dens and summering elk combined with different traffic levels. Study results can help wildlife managers to anticipate the movements and establishment of wolf packs as they expand into areas with migratory or resident prey populations, varying levels of human activity, and front-country rangelands with potential for conflicts with livestock.
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Ciervos/fisiología , Ecosistema , Actividades Humanas , Lobos/fisiología , Animales , Conservación de los Recursos Naturales , Demografía , Humanos , Estaciones del Año , WyomingRESUMEN
Waste stream characteristics must be understood to tackle waste management problems in Kathmandu Metropolitan City (KMC), Nepal. Three-stage stratified cluster sampling was used to evaluate solid waste data collected from 336 households in KMC. This information was combined with data collected regarding waste from restaurants, hotels, schools and streets. The study found that 497.3 g capita(-1) day(-1) of solid waste was generated from households and 48.5, 113.3 and 26.1 kg facility(-1) day(-1) of waste was generated from restaurants, hotels and schools, respectively. Street litter measured 69.3 metric tons day(-1). The average municipal solid waste generation rate was 523.8 metric tons day(-1) or 0.66 kg capita(-1) day(-1) as compared to the 320 metric tons day(-1) reported by the city. The coefficient of correlation between the number of people and the amount of waste produced was 0.94. Key household waste constituents included 71% organic wastes, 12% plastics, 7.5% paper and paper products, 5% dirt and construction debris and 1% hazardous wastes. Although the waste composition varied depending on the source, the composition analysis of waste from restaurants, hotels, schools and streets showed a high percentage of organic wastes. These numbers suggest a greater potential for recovery of organic wastes via composting and there is an opportunity for recycling. Because there is no previous inquiry of this scale in reporting comprehensive municipal solid waste generation in Nepal, this study can be treated as a baseline for other Nepalese municipalities.
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Eliminación de Residuos/métodos , Ciudades , Residuos Peligrosos , Vivienda , Industrias , NepalRESUMEN
Wildlife conservationists design monitoring programs to assess population dynamics, project future population states, and evaluate the impacts of management actions on populations. Because agency mandates and conservation laws call for monitoring data to elicit management responses, it is imperative to design programs that match the administrative scale for which management decisions are made. We describe a program to monitor population trends in American beaver (Castor canadensis) on the US Department of Agriculture, Black Hills National Forest (BHNF) in southwestern South Dakota and northeastern Wyoming, USA. Beaver have been designated as a management indicator species on the BHNF because of their association with riparian and aquatic habitats and its status as a keystone species. We designed our program to monitor the density of beaver food caches (abundance) within sampling units with beaver and the proportion of sampling units with beavers present at the scale of a national forest. We designated watersheds as sampling units in a stratified random sampling design that we developed based on habitat modeling results. Habitat modeling indicated that the most suitable beaver habitat was near perennial water, near aspen (Populus tremuloides) and willow (Salix spp.), and in low gradient streams at lower elevations. Results from the initial monitoring period in October 2007 allowed us to assess costs and logistical considerations, validate our habitat model, and conduct power analyses to assess whether our sampling design could detect the level of declines in beaver stated in the monitoring objectives. Beaver food caches were located in 20 of 52 sampled watersheds. Monitoring 20 to 25 watersheds with beaver should provide sufficient power to detect 15-40% declines in the beaver food cache index as well as a twofold decline in the odds of beaver being present in watersheds. Indices of abundance, such as the beaver food cache index, provide a practical measure of population status to conduct long-term monitoring across broad landscapes such as national forests.
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Monitoreo del Ambiente/métodos , Roedores , Árboles , Animales , Dinámica Poblacional , Estados UnidosRESUMEN
Relatively few studies have been performed to characterize municipal solid waste (MSW) at household level. This is due in part to the difficulties involved with collecting the data and selecting an appropriate statistical sample size. The previous studies identified in this paper have used statistical tools appropriate for analysing data collected at a material recovery facility or landfill site. This study demonstrates a statistically sound and efficient approach for characterizing MSW at the household level. Moreover, a household approach also allowed for consideration of the socio-economic conditions, level of waste generation, geography, and demography. The study utilized two-stage cluster sampling within strata in Kathmandu Metropolitan City (KMC) to measure MSW for 2 weeks. In KMC, the average household solid waste generation was 161.2 g capita( -1) day(- 1)with an average generation rate between 137.7 and 184.6 g capita(-1) day(-1) for a 95% confidence interval and 14.5% relative margin of error. The results show a positive relation between income and waste production rate. Organic waste was the biggest portion of MSW, and hazardous waste was the smallest of the total. Sample size considerations suggest that 273 households are required in KMC to attain a 10% relative margin of error with a 95% confidence interval.