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1.
J Environ Qual ; 53(2): 232-240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348512

RESUMO

Saturated buffers are a newly developed agricultural best management practice used to redirect tile flow away from waterways, thereby mitigating nutrient losses and downstream eutrophication. This study evaluated the potential benefits of a novel saturated buffer design, which included pitchfork-shaped (PF) dispersion lines and a backflow check valve, that was installed alongside a traditional or standard (ST) buffer on a field in Moultrie County, Illinois, in the spring of 2019. Daily flow measurements and routine water samples were used to monitor the movement of water through both buffers and estimate nutrient loads. During observation days in 2020 and 2021, the PF buffer diverted 35% and 1.9% of incoming tile flow, respectively, while the ST buffer increased effluent rates by 116% and 137% over the same period. Both the PF and ST buffers experienced backflow from 30% to 47% of the monitoring period, well above the often reported 5%. Ultimately, the efficacy of saturated buffers could be improved with minimal, low-cost additions to their designs. Check valves are a simple supplement to saturated buffer design that can enhance flow diversion and potential nutrient removal. Added dispersion lines provide more opportunity for diversion of tile flow; however, they require more land to be removed from agricultural production and could increase backflow volumes, so the costs and benefits should be weighed.


Assuntos
Agricultura , Eutrofização , Illinois , Estações do Ano , Água
2.
J Morphol ; 283(10): 1337-1349, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36041006

RESUMO

The morphology of the mammalian middle ear-including the size, shape, and stiffness of individual ossicles-controls their vibrational response to sound and, is closely related to an animal's auditory capabilities. While the relationship between middle ear morphology and hearing frequency has been explored in living carnivorans, the size and shape of ossicles in fossil carnivorans have been sparsely documented. In this study, we present the first morphological data on four iconic carnivoran taxa from the Rancho La Brea Tar Pits: Smilodon fatalis, Panthera atrox, Canis dirus, and Arctodus simus. These data are contextualized with samples of extant felids, canids, and ursids to determine the extent to which the ossicles of these iconic fossil taxa resemble their living relatives. Six, five, and seven linear measurements were taken from the malleus, incus, and stapes, respectively. Comparisons of geometric means reveal that the ossicles of fossil canids and felids are similar in size to living analogs, but those of A. simus are significantly larger than those of any living ursid. Further, principal components analyses demonstrate close morphological affinities between fossil and extant taxa within canids and felids, and again, a greater disparity between fossil and extant ursids. Canids and ursids occupy distinct regions of the morphospace, yet both overlap the morphological range spanned by felids. While some elements-for example, the stapes-require further specimens to facilitate more nuanced interpretations of variation, our findings underscore the need for concerted efforts towards identifying and preserving these bones within fossil assemblages.


Assuntos
Felidae , Fósseis , Animais , Orelha Média , Felidae/anatomia & histologia , Mamíferos , Análise de Componente Principal
3.
BMJ Open Sport Exerc Med ; 7(1): e000924, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33768961

RESUMO

OBJECTIVES: To establish pupil fitness levels, and the relationship to global norms and physical education (PE) enjoyment. To measure and describe physical activity (PA) levels during secondary school PE lessons, in the context of recommended levels, and how levels vary with activity and lesson type. METHODS: A cross-sectional design; 10 697 pupils aged 12.5 (SD 0.30) years; pupils who completed a multistage fitness test and wore accelerometers to measure PA during PE lessons. Multilevel models estimated fitness and PE activity levels, accounting for school and class-level clustering. RESULTS: Cardiorespiratory fitness was higher in boys than girls (ß=-0.48; 95% CI -0.56 to -0.39, p<0.001), within absolute terms 51% of boys and 54% of girls above the 50th percentile of global norms. On average, pupils spent 23.8% of PE lessons in moderate-to-vigorous PA (MVPA), and 7.1% in vigorous PA (VPA). Fitness-focused lessons recorded most VPA in co-educational (ß=1.09; 95% CI 0.43 to 1.74) and boys-only lessons (ß=0.32; 95% CI -0.21 to 0.85). In girls-only lessons, track athletics recorded most VPA (ß=0.13; 95% CI -0.50 to 0.75) and net/wall/racket games (ß=0.97; 95% CI 0.12 to 1.82) the most MVPA. For all lesson types, field athletics was least active (ß=-0.85; 95% CI -1.33 to -0.36). There was a relationship of enjoyment of PE to fitness (ß=1.03; 95% CI 0.83 to 1.23), and this relationship did not vary with sex (ß=-0.14 to 0.23; 95% CI -0.16 to 0.60). CONCLUSIONS: PE lessons were inactive compared with current guidelines. We propose that if we are to continue to develop a range of sporting skills in schools at the same time as increasing levels of fitness and PA, there is a need to introduce additional sessions of PE activity focused on increasing physical activity. TRIAL REGISTRATION NUMBER: NCT03286725.

4.
BMC Public Health ; 20(1): 1590, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087081

RESUMO

BACKGROUND: Pupils in secondary schools do not meet the targets for physical activity levels during physical education (PE) sessions, and there is a lack of data on the vigorous physical activity domain (VPA) in PE known to be positively associated with cardio metabolic health While PE session intensity depends on a variety of factors, the large majority of studies investigating these factors have not taken into account the nested structure of this type of data set. Therefore, the aim of this study was to investigate the relationship between various factors (gender, activity type, class location and class composition) and various activity levels during PE classes in secondary schools, using a multi-level statistical approach. METHODS: Year eight (12-13 years old) adolescents (201 boys and 106 girls) from six schools were fitted with accelerometers during one PE session each, to determine the percentage (%) of the PE session time spent in sedentary (SPA), light (LPA), moderate (MPA), vigorous (VPA) and moderate-to-vigorous (MVPA) intensity levels. Two- and three-level (pupils, n = 307; classes, n = 13, schools, n = 6) mixed-effect models were used to assess the relationship between accelerometer-measured physical activity levels (% of class time spent in various activity levels) and gender, activity type, class location and composition. RESULTS: Participants engaged in MVPA and VPA for 30.7 ± 1.2% and 11.5 ± 0.8% of PE classes, respectively. Overall, no significant association between gender or class composition and PA was shown. A significant relationship between activity type and PA was observed, with Artistic classes significantly less active than Fitness classes for VPA (5.4 ± 4.5 vs. 12.5 ± 7.1%, p = 0.043, d:1.19). We also found a significant association between class location and PA, with significantly less time spent in SPA (24.8 ± 4.8% vs. 30.0 ± 3.4%, p = 0.042, d:0.77) and significantly more time spent in VPA (12.4 ± 3.7% vs. 7.6 ± 2.0%, p = 0.022, d:1.93) and MVPA (32.3 ± 6.7% vs.24.8 ± 3.8%, p = 0.024, d:1.33) in outdoors vs. indoors classes. CONCLUSIONS: The results suggest that class location and activity type could be associated with the intensity of PA in PE. It is essential to take into account the clustered nature of this type of data in similar studies if the sample size allows it.


Assuntos
Educação Física e Treinamento , Instituições Acadêmicas , Adolescente , Estudos Transversais , Etnicidade , Exercício Físico , Feminino , Humanos , Masculino
5.
Trends Neurosci Educ ; 20: 100134, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917300

RESUMO

BACKGROUND: The randomised controlled trial (RCT) design is increasingly common among studies seeking good-quality evidence to advance educational neuroscience, but conducting RCTs in schools is challenging. Fit to Study, one of six such trials funded by the Education Endowment Foundation and Wellcome Trust, tested an intervention to increase vigorous physical activity during PE lessons on maths attainment among pupils aged 12-13. This review of designing and conducting an RCT in 104 schools is intended as a resource on which researchers might draw for future studies. METHOD: We consider intervention design and delivery; recruitment, retention, trial management, data collection and analysis including ethical considerations and working with evaluators. RESULTS: Teacher training, intervention delivery and data collection during large-scale RCTs require a flexible approach appropriate to educational settings, which in turn entails planning and resources. CONCLUSION: Simple interventions, with few outcome measures and minimal missing data, are preferable to more complex designs.


Assuntos
Exercício Físico/psicologia , Serviços de Saúde Escolar/tendências , Adolescente , Encéfalo , Criança , Cognição , Docentes , Humanos , Aprendizagem , Educação Física e Treinamento/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas , Estudantes
6.
J Morphol ; 281(6): 646-652, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32302429

RESUMO

The Rancho La Brea (RLB) fossil collection housed at the La Brea Tar Pits and Museum in Los Angeles, California, is one of the richest collections of carnivoran fossils in the world. The collection is also particularly well known for the preservation of rare and understudied bones in the tar, including the small bony apparatus that is of particular interest to this study, the hyoid. The La Brea collection houses hyoids from several extinct carnivoran species, some of the most common being those of Canis dirus (the dire wolf) and Canis latrans (the coyote). In this study, we compare fossilized hyoid elements from these two canids to samples from modern large congeners, namely: Canis lupus (the gray wolf), Canis rufus (the red wolf), and modern C. latrans. Seven or nine measurements were taken on each bone of the hyoid apparatus, and principal component analyses were performed in order to determine statistical significance between species. For most of the bones, the majority of the variation was driven by size. Dire wolves could be clearly differentiated from all other canids for all elements; the hyoid apparatus of C. dirus is larger and more robust than that of C. lupus. Most of the bony elements could not be distinguished between red wolves or modern coyotes. However, there are enough, complete fossil coyote basihyoids to compare with those of their modern relatives, and in several metrics (both PC shapes and overall size), RLB and modern C. latrans are significantly different. As larger hyoids have been associated with a lower vocal frequency, this distinction would have resulted in the vocalizations of C. dirus occurring at a lower frequency than those produced by C. lupus and perhaps lower vocalizations in ice age coyotes than their modern relatives. RESEARCH HIGHLIGHTS: We quantify morphological differences in the hyoid of dire wolves (Canis dirus) relative to extant grey wolves (Canis lupus), and hypothesize that, as larger hyoids have been associated with a lower vocal frequency, the vocalizations of C. dirus might have occurred at a lower frequency than those by C. lupus. Likewise, modern and fossil coyotes (Canis latrans) show a significant difference in basihyoid size and shape, potentially indicating that modern and ancient coyotes might have sounded differently.


Assuntos
Anatomia Comparada , Fósseis , Osso Hioide/anatomia & histologia , Vocalização Animal/fisiologia , Lobos/anatomia & histologia , Animais , California , Tamanho do Órgão , Análise de Componente Principal
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