57 results match your criteria paths slopes

Spatiotemporal slope stability analytics for failure estimation (SSSAFE): linking radar data to the fundamental dynamics of granular failure.

Sci Rep 2021 May 6;11(1):9729. Epub 2021 May 6.

Melbourne School of Engineering, University of Melbourne, Melbourne, Australia.

Impending catastrophic failure of granular earth slopes manifests distinct kinematic patterns in space and time. While risk assessments of slope failure hazards have routinely relied on the monitoring of ground motion, such precursory failure patterns remain poorly understood. A key challenge is the multiplicity of spatiotemporal scales and dynamical regimes. Read More

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Quantifying energetic costs and defining energy landscapes experienced by grizzly bears.

J Exp Biol 2021 Mar 30;224(Pt 6). Epub 2021 Mar 30.

School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA.

Animal movements are major determinants of energy expenditure and ultimately the cost-benefit of landscape use. Thus, we sought to understand those costs and how grizzly bears () move in mountainous landscapes. We trained captive grizzly bears to walk on a horizontal treadmill and up and down 10% and 20% slopes. Read More

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Valuing Cultural Activities Moderating the Association Between Alcohol Expectancies and Alcohol Use Among First Nation Adolescents.

J Stud Alcohol Drugs 2021 01;82(1):112-120

PATHS Lab, University of Rhode Island Department of Psychology, Kingston, Rhode Island.

Objective: Indigenous youth often exhibit high rates of alcohol use and experience disproportionate alcohol-related harm. We examined the moderating role that valuing cultural activities has on the relationship between positive alcohol expectancies and alcohol use and heavy drinking in a sample of Indigenous youth.

Method: First Nation adolescents between ages 11 and 18 living on a reserve in eastern Canada (N = 106; mean age = 14. Read More

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January 2021

Bipedal microwalkers actuated by oscillating magnetic fields.

Soft Matter 2020 Sep 19;16(34):7927-7934. Epub 2020 Aug 19.

State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, China.

Microrobots have attracted considerable attention due to their immense potential for biomedical and engineering applications in recent years. Inspired by human walks, a bipedal microwalker capable of standing and walking like humans regulated by external weak magnetic fields was reported in this paper. The walker has a submillimeter size and a simple arrowhead shape. Read More

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September 2020

Path integration in a three-dimensional world: the case of desert ants.

J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2020 05 4;206(3):379-387. Epub 2020 Feb 4.

Behavioural Physiology Group, Department of Biology, Humboldt-Universität zu Berlin, Philippstr. 13, Haus 18, 10099, Berlin, Germany.

Desert ants use path integration to return from foraging excursions on a shortcut way to their nests. Intriguingly, when walking over hills, the ants incorporate the ground distance, the paths' projection to the horizontal plane, into their path integrator. This review discusses how Cataglyphis may solve this computational feat. Read More

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Lateral mobilization of soil carbon induced by runoff along karstic slopes.

J Environ Manage 2020 Apr 13;260:110091. Epub 2020 Jan 13.

Soil and Water Department, Estación Experimental de Aula Dei (EEAD-CSIC), Zaragoza, Spain. Electronic address:

Soil erosion induced by runoff is a main hydrological pathway for lateral transport of carbon in terrestrial landscapes. More information about how water erosion influences the carbon gains and losses at different erosional and depositional landform positions is critical, especially in fragile agroecosystems with a variety of land uses and ephemeral hydrological and sedimentological pulses, typical of Mediterranean environments. The purpose of this study is to characterize the lateral mobilization of soil organic and inorganic carbon (SOC and SIC) along topographically driven transects over a period of four decades in a sub-humid karstic area in northern Spain. Read More

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Dynamic associations between religiousness and self-regulation across adolescence into young adulthood.

Dev Psychol 2020 Jan 31;56(1):180-197. Epub 2019 Oct 31.

Department of Psychology.

Prior research has demonstrated that religiousness is associated with and potentially facilitative of self-regulation, though most of the research has been cross-sectional. The present longitudinal study examined dynamic relations between religiousness development and self-regulation formation from early adolescence into young adulthood. The sample included 500 U. Read More

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January 2020

Tree-ring reconstruction of snow avalanche activity: Does avalanche path selection matter?

Sci Total Environ 2019 Sep 17;684:496-508. Epub 2019 May 17.

Université Clermont Auvergne, CNRS, Université de Limoges, GEOLAB, F-63000 Clermont-Ferrand, France.

In the current context of anthropogenic global warming, one of the purposes of dendrogeomorphic analyses is to provide long and continuous chronologies of mass movements, so as to detect potential trends or shift related to increasing temperatures. However, on documented slopes, the comparison between historical archives and tree-ring records suggests that dendrogeomorphic reconstructions systematically underestimate the natural activity of the process under investigation. In the specific case of snow avalanches, underestimation generally amounts to 50% and the main causes generally given for this difference are related to the magnitude of past events. Read More

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September 2019

Aberration-resistible topological charge determination of annular-shaped optical vortex beams using Shack-Hartmann wavefront sensor.

Opt Express 2019 Mar;27(5):7803-7821

Determining topological charge (TC) of optical vortex (OV) beams is important for many applications, such as optical measurement and information transmission through long-distance propagation. In this application, the OV beams usually have an annular intensity profile at the receiving end and are inevitably distorted by aberrations during propagation. In this paper, we propose a simple, direct, and aberration-resistible method to determine the TC value of this annular-shaped OV beam with a Shack-Hartmann wavefront sensor (SH-WFS). Read More

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Modification of the RUSLE slope length and steepness factor (LS-factor) based on rainfall experiments at steep alpine grasslands.

MethodsX 2019 26;6:219-229. Epub 2019 Jan 26.

Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.

The slope length and slope steepness factor (LS-factor) is one of five factors of the Universal Soil Loss Equation (USLE) and its revised version (RUSLE) describing the influence of topography on soil erosion risk. The LS-factor was originally developed for slopes less than 50% inclination and has not been tested for steeper slopes. To overcome this limitation, we adapted both factors slope length L and slope steepness S for conditions experimentally observed at Swiss alpine grasslands. Read More

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January 2019

Quantumness and state boundaries hidden in supercritical helium-4: A path integral centroid molecular dynamics study.

J Chem Phys 2018 Nov;149(20):204504

Division of Chemistry, Graduate School of Humanities and Sciences, Nara Women's University, Nara 630-8506, Japan.

Isothermal-isobaric path integral centroid molecular dynamics simulations were conducted for fluid He at more than 600 state points in the proximity of the critical point to reveal the detailed states and relevant quantumness underlying the supercritical state. Through intensive analyses of the thermodynamic, dynamic, and quantum properties, we revealed the hidden state boundaries that separate the liquid-like and gas-like states in the supercritical region of this fluid. The Widom line, defined as the locus of the maxima of isobaric heat capacity , is also the quantum boundary at which there are changes in the isobaric temperature-dependence of the quantum wavelength, , i. Read More

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November 2018

Spatially distributed hydro-chemical data with temporally high-resolution is needed to adequately assess the hydrological functioning of headwater catchments.

Sci Total Environ 2019 Feb 20;651(Pt 1):1613-1626. Epub 2018 Sep 20.

Institute for Landscape Ecology and Resources Management (ILR), Justus Liebig University Giessen, Giessen, Germany.

We demonstrated the great value of spatially distributed and temporally high-resolution hydro-chemical data to enhance knowledge about the intra-catchment variability of flow processes and the runoff composition of individual storms in a tropical alpine (Páramo) ecosystem. In this study, water sources (rainfall, spring water, and water from soil layers of Histosols and Andosols) and nested streams were sampled bi-weekly (2013-2014), including three storm high-resolution events (5-240 min). Water samples were analyzed for 14 tracers including electrical conductivity (EC) and rare earth trace elements and used as input to perform End-Member Mixing Analysis (EMMA). Read More

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February 2019

Impacts of China's Grain for Green Program on Migration and Household Income.

Environ Manage 2018 09 8;62(3):489-499. Epub 2018 May 8.

Gillings School of Global Public Health, University of North Carolina, 206W Franklin Street, CB #8120, Chapel Hill, NC, 27516, USA.

In the late 1990s, China's Yangtze and Yellow River Basins suffered devastating natural disasters widely attributed to the degradation of soil and water resources. The Government of China responded with a number of major environmental programs, the most expensive and influential of which, the Grain for Green (GfG) Program, was implemented widely from 1999. Under the GfG Program-also known as the Sloping Land Conversion or Conversion of Cropland to Forest Program-the central government compensates farmers to convert cropland on steep slopes or otherwise ecologically sensitive areas to forest or grassland. Read More

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September 2018

Percolation in protein sequence space.

PLoS One 2017 20;12(12):e0189646. Epub 2017 Dec 20.

Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany.

The currently known protein sequences are not distributed equally in sequence space, but cluster into families. Analyzing the cluster size distribution gives a glimpse of the large and unknown extant protein sequence space, which has been explored during evolution. For six protein superfamilies with different fold and function, the cluster size distributions followed a power law with slopes between 2. Read More

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January 2018

The regional variation of denitrification phenotypes under anoxic incubation with soils from eight forested catchments in different climate zones of China.

Sci Total Environ 2018 Feb 2;615:319-329. Epub 2017 Oct 2.

Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.

Denitrification characteristics of forest soils from eight headwater catchments in China were investigated in this study, along a climatic gradient from the tropics in the South to the temperate zones. Within each catchment, different landscape positions along hydrological flow paths were also considered, including well-drained soils on hill slopes and poorly drained soils in groundwater discharge zones. The results showed that instantaneous denitrification rates were much greater in soils from the northern sites than those from the southern sites (with the average of 110. Read More

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February 2018

[Research on Cloud Phase Detemination Using Infrared Emissivity Spectrum Data (2): Retrieval of Cloud Effective Radius and Water Path].

Guang Pu Xue Yu Guang Pu Fen Xi 2016 Dec;36(12):3895-906

The cloud microphysical properties such as cloud effective radius and cloud water path are fundamental properties for understanding the cloud formation, radiative impacts and interactions with aerosol and precipitation. The downwelling infrared radiance spectra is studied here to retrieve microphysical properties of clouds. The sensitivity of the downwelling radiance spectra and cloud emissivity spectra to the liquid cloud and ice cloud effective radius and optical depth is analyzed. Read More

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December 2016

A virtual water maze revisited: Two-year changes in navigation performance and their neural correlates in healthy adults.

Neuroimage 2017 02 19;146:492-506. Epub 2016 Sep 19.

Institute of Gerontology, Wayne State University, Detroit, MI, USA; Department of Psychology, Wayne State University, Detroit, MI, USA.

Age-related declines in spatial navigation are associated with deficits in procedural and episodic memory and deterioration of their neural substrates. For the lack of longitudinal evidence, the pace and magnitude of these declines and their neural mediators remain unclear. Here we examined virtual navigation in healthy adults (N=213, age 18-77 years) tested twice, two years apart, with complementary indices of navigation performance (path length and complexity) measured over six learning trials at each occasion. Read More

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February 2017

Development of a Robotic Assembly for Analyzing the Instantaneous Axis of Rotation of the Foot Ankle Complex.

Appl Bionics Biomech 2016 23;2016:5985137. Epub 2016 Mar 23.

BioRobotics Laboratory, Department of Orthopaedic Surgery and Biomedical Engineering, The University of Tennessee Health Science Center, 956 Court Avenue, Suite E226, Memphis, TN 38163, USA.

Ankle instantaneous axis of rotation (IAR) measurements represent a more complete parameter for characterizing joint motion. However, few studies have implemented this measurement to study normal, injured, or pathological foot ankle biomechanics. A novel testing protocol was developed to simulate aspects of in vivo foot ankle mechanics during mid-stance gait in a human cadaveric specimen. Read More

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Geographic variation in floral allometry suggests repeated transitions between selfing and outcrossing in a mixed mating plant.

Am J Bot 2015 May 21;102(5):745-57. Epub 2015 May 21.

W355 Seeley G. Mudd Hall, Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853.

Premise Of The Study: Isometric and allometric scaling of a conserved floral plan could provide a parsimonious mechanism for rapid and reversible transitions between breeding systems. This scaling may occur during transitions between predominant autogamy and xenogamy, contributing to the maintenance of a stable mixed mating system.

Methods: We compared nine disjunct populations of the polytypic, mixed mating species Oenothera flava (Onagraceae) to two parapatric relatives, the obligately xenogamous species O. Read More

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Pathways of Leymus chinensis Individual Aboveground Biomass Decline in Natural Semiarid Grassland Induced by Overgrazing: A Study at the Plant Functional Trait Scale.

PLoS One 2015 5;10(5):e0124443. Epub 2015 May 5.

Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Ministry of Agriculture Key Laboratory of Grassland Resources and Utilization, Hohhot, China.

Natural grassland productivity, which is based on an individual plant's aboveground biomass (AB) and its interaction with herbivores, can obviously affect terrestrial ecosystem services and the grassland's agricultural production. As plant traits have been linked to both AB and ecosystem success, they may provide a useful approach to understand the changes in individual plants and grassland productivity in response to grazing on a generic level. Unfortunately, the current lack of studies on how plant traits affect AB affected by herbivores leaves a major gap in our understanding of the mechanism of grassland productivity decline. Read More

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Severity of urban cycling injuries and the relationship with personal, trip, route and crash characteristics: analyses using four severity metrics.

BMJ Open 2015 Jan 5;5(1):e006654. Epub 2015 Jan 5.

School of Population and Public Health, University of British Columbia, Vancouver, Canada.

Objective: To examine the relationship between cycling injury severity and personal, trip, route and crash characteristics.

Methods: Data from a previous study of injury risk, conducted in Toronto and Vancouver, Canada, were used to classify injury severity using four metrics: (1) did not continue trip by bike; (2) transported to hospital by ambulance; (3) admitted to hospital; and (4) Canadian Triage and Acuity Scale (CTAS). Multiple logistic regression was used to examine associations with personal, trip, route and crash characteristics. Read More

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January 2015

Patterns of response times and response choices to science questions: the influence of relative processing time.

Cogn Sci 2015 Apr 18;39(3):496-537. Epub 2014 Sep 18.

Department of Physics, Ohio State University.

We report on five experiments investigating response choices and response times to simple science questions that evoke student "misconceptions," and we construct a simple model to explain the patterns of response choices. Physics students were asked to compare a physical quantity represented by the slope, such as speed, on simple physics graphs. We found that response times of incorrect answers, resulting from comparing heights, were faster than response times of correct answers comparing slopes. Read More

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Dynamic change in spring habitat use by the brown eared pheasant (Crossptilon mantchuricum) in the Huanglong mountains, Yanan City, Shaanxi Province, China.

Zoolog Sci 2014 Aug;31(8):529-34

1 College of Life Science and Technology, Yangtze Normal University, Fuling 408100, P. R. China.

Characterization of foraging-site preferences of threatened and endangered species is a key component of effective habitat conservation. We studied foraging-site selection by the brown eared pheasant (Crossoptilon mantchuricum) in the Huanglongshan Nature Reserve, Yanan City, Shaanxi Province, China, from early February to end of May 2011. We identified feeding sites by locating tracks and scratches characteristic of the birds, and compared habitat characteristics at these sites to those at randomly selected sites across the study area. Read More

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Modulation of phase durations, phase variations, and temporal coordination of the four limbs during quadrupedal split-belt locomotion in intact adult cats.

J Neurophysiol 2014 Oct 16;112(8):1825-37. Epub 2014 Jul 16.

Department of Physiology and Biophysics, Faculty of Medicine and Health Sciences, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada

Stepping along curvilinear paths produces speed differences between the inner and outer limb(s). This can be reproduced experimentally by independently controlling left and right speeds with split-belt locomotion. Here we provide additional details on the pattern of the four limbs during quadrupedal split-belt locomotion in intact cats. Read More

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October 2014

Does perceived racial discrimination predict changes in psychological distress and substance use over time? An examination among Black emerging adults.

Dev Psychol 2014 Jul 14;50(7):1910-8. Epub 2014 Apr 14.

Department of Health Behavior & Health Education, School of Public Health, University of Michigan.

We assessed whether perceived discrimination predicted changes in psychological distress and substance use over time and whether psychological distress and substance use predicted change in perceived discrimination over time. We also assessed whether associations between these constructs varied by gender. Our sample included 607 Black emerging adults (53% female) followed for 4 years. Read More

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Strategies for navigating large areas: a GIS spatial ecology analysis of the bearded saki monkey, Chiropotes sagulatus, in Suriname.

Am J Primatol 2014 Jun 16;76(6):586-95. Epub 2013 Dec 16.

Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia.

Animals with long day paths and large home ranges expend a considerable amount of energy on travel. Studies have shown that in the interest of reducing energy expenditure, animals selectively navigate the landscape using a variety of strategies. However, these studies have generally focused on terrestrial animals. Read More

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Quadrupedal gaits in hexapod animals - inter-leg coordination in free-walking adult stick insects.

J Exp Biol 2012 Dec 12;215(Pt 24):4255-66. Epub 2012 Sep 12.

Emmy Noether Research Group of Computational Biology, Department of Animal Physiology, Institute of Zoology, University of Cologne, Cologne, Germany.

The analysis of inter-leg coordination in insect walking is generally a study of six-legged locomotion. For decades, the stick insect Carausius morosus has been instrumental for unravelling the rules and mechanisms that control leg coordination in hexapeds. We analysed inter-leg coordination in C. Read More

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December 2012

Evolutionary paths of streptococcal and staphylococcal superantigens.

BMC Genomics 2012 Aug 17;13:404. Epub 2012 Aug 17.

Department of Infectious Diseases, National Center for Global Health and Medicine, Tokyo 162-8655, Japan.

Background: Streptococcus pyogenes (GAS) harbors several superantigens (SAgs) in the prophage region of its genome, although speG and smez are not located in this region. The diversity of SAgs is thought to arise during horizontal transfer, but their evolutionary pathways have not yet been determined. We recently completed sequencing the entire genome of S. Read More

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Photophobic behavior of maize roots.

Plant Signal Behav 2012 Jul 1;7(7):874-8. Epub 2012 Jul 1.

IZMB, University of Bonn, Bonn, Germany.

Primary roots of young maize seedlings showed peculiar growth behavior when challenged by placing them on a slope, or if whole seedlings were turned upside down. Importantly, this behavior was dependent on the light conditions. If roots were placed on slopes in the dark, they performed "crawling" behavior and advanced rapidly up the slope. Read More

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Workload comparison between hiking and indoor physical activity.

J Strength Cond Res 2012 Oct;26(10):2883-9

Department of Physiology and Pharmacology V. Ersparmer, Sapienza University of Rome, Rome, Italy.

Walking is a physical activity able to maintain and improve aerobic fitness. This activity can easily be performed in all seasons both outdoors and indoors, but when it is performed in its natural environment, the use of specific equipment is required. In particular, it has been demonstrated that the use of trekking boots (TBs) induces a larger workload than those used indoors. Read More

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October 2012