2,157 research outputs found
Understanding differences in regional poverty rates
An examination of the huge variation in U.S. regional poverty rates, showing that although demographic, policy, and cost-of-living factors all play a role, economic differences are key.Income ; Regional economics
OBIA for combining LiDAR and multispectral data to characterize forested areas and land cover in a tropical region
International audiencePrioritizing and designing forest restoration strategies requires an adequate survey to inform on the status (degraded or not) of forest types and the human disturbances over a territory. Very High Spatial Resolution (VHSR) remotely sensed data offers valuable information for performing such survey. We present in this study an OBIA methodology for mapping forest types at risk and land cover in a tropical context (Mayotte Island) combining LiDAR data (1 m pixel), VHSR multispectral images (Spot 5 XS 10 m pixel and orthophotos 0.5 m pixel) and ancillary data (existing thematic information). A Digital Canopy Model (DCM) was derived from LiDAR data and additional information was built from the DCM in order to better take into account the horizontal variability of canopy height: max and high Pass filters (3m x 3m kernel size) and Haralick variance texture image (51m x 51m kernel size). OBIA emerges as a suitable framework for exploiting multisource information during segmentation as well as during the classification process. A precise map (84% total accuracy) was obtained informing on (i) surfaces of forest types (defined according to their structure, i.e. canopy height of forest patches for specific type); (ii) degradation (identified in the heterogeneity of canopy height and presence of eroded areas) and (iii) human disturbances. Improvements can be made when discriminating forest types according to their composition (deciduous, evergreen or mixed), in particular by exploiting a more radiometrically homogenous VHSR multispectral image
Nutrition for master athletes: From challenges to optimisation strategies
Master athletes are genuine examples of successful ageing thanks to their capacity of maintaining a high level of sports performance during their entire life. Within the last decade many studies have focused on the evolution of performance in many sports with ageing, as well as on the training modalities to reach such performance. On the contrary, there is a paucity of data on the nutritional habits of master athletes and the question of whether they need to adapt their nutrition to the ageing process remains unsolved. This is within this context of the optimisation of nutrition for master athletes that this review stands. The aim is to identify the potential nutritional challenges encountered by master athletes and how to handle them through adapted nutritional strategies. Given the lack of data specific to master athletes, studies including master athletes are considered as a priority, though we also make inferences based on nutrition for young adults and perturbations induced by ageing in non-athletic populations. The first part of this opinion paper tackles the first challenge faced by master athletes which is the gradual reduction in energy intake with ageing. The second challenge is the anabolic resistance and the need for increased protein intake. The third nutritional challenge we present is the episodes of metabolic crisis master athletes may face throughout life. Finally, we gather the main nutritional recommendations for master athletes and suggest the next stage of research. © 2019 ACAPS
Larval culture of the calico scallop, Argopecten gibbus
Mature calico scallops, Argopecten gibbus, collected from the grounds off Cape Kennedy, Florida, were induced to spawn in the laboratory. Fertilized eggs were reared to postlarvae in sea water of 23° C ± 2.0° C at a salinity of 35 %o. The external morphology of eggs and developing larval stages are described
Nutrition for master athletes: is there a need for specific recommendations?
Master athletes are often considered exemplars of successful aging, thanks to their capacity to maintain a high sports performance during their entire life. A high training capacity, regular participation in sporting competitions, and delayed alterations in body composition and physiological capacities have been listed among the main factors contributing to impressive master athletesâ performances. However, there is a paucity of data on the metabolism and dietary habits of master athletes, and the question of whether they need to adapt their nutrition to the aging process remains open. Herein, the authors presented a contemporary overview of themetabolic challenges associated with aging, including the risk of low energy availability, anabolic resistance, and periods of metabolic crisis due to forced immobilization. After assembling scientific evidence to show that master athletes must adapt their dietary intake, the authors proposed a summary of nutritional recommendations for master athletes and suggested the next stage of research
An OBIA for fine-scale land cover spatial analysis over broad territories: demonstration through riparian corridor and artificial sprawl studies in France
International audienceSpatial analysis using fine-scale information over broad territories is essential to define efficient restoration strategies from local to national scale. We designed an OBIA dedicated to produce operationally reliable fine-scale information over broad territories. The originality of our OBIA lies particularly in the top-down approach for the construction of the classification tree and the use of âknowledge-based rulesâ classification technique. The implementation of this OBIA over the two study areas â (i) the Normandy region for riparian area land cover mapping (5600 kmÂČ riparian area) and (ii) fours departments over the Languedoc-Roussillon region (22644 kmÂČ) â demonstrates the operability of our approach (time-efficient, reproducible, transferable, portable). Broad scale spatial analysis conducted from resulting maps demonstrate the interest of using fine-scale information and highlight that OBIA, following our approach, will be at very short run a broadly applicable method to carry out such analysis
Rotational Velocities of Individual Components in Very Low Mass Binaries
We present rotational velocities for individual components of 11 very low mass (VLM) binaries with spectral types between M7 and L7.5. These results are based on observations taken with the near-infrared spectrograph, NIRSPEC, and the Keck II laser guide star adaptive optics system. We find that the observed sources tend to be rapid rotators (v sin i > 10 km s^(â1)), consistent with previous seeing-limited measurements of VLM objects. The two sources with the largest v sin i, LP 349â25B and HD 130948C, are rotating at ~30% of their break-up speed, and are among the most rapidly rotating VLM objects known. Furthermore, five binary systems, all with orbital semimajor axes âŸ3.5 AU, have component v sin i values that differ by greater than 3Ï. To bring the binary components with discrepant rotational velocities into agreement would require the rotational axes to be inclined with respect to each other, and that at least one component is inclined with respect to the orbital plane. Alternatively, each component could be rotating at a different rate, even though they have similar spectral types. Both differing rotational velocities and inclinations have implications for binary star formation and evolution. We also investigate possible dynamical evolution in the triple system HD 130948AâBC. The close binary brown dwarfs B and C have significantly different v sin i values. We demonstrate that components B and C could have been torqued into misalignment by the primary star, A, via orbital precession. Such a scenario can also be applied to another triple system in our sample, GJ 569AâBab. Interactions such as these may play an important role in the dynamical evolution of VLM binaries. Finally, we note that two of the binaries with large differences in component v sin i, LP 349â25AB and 2MASS 0746+20AB, are also known radio sources
Low temperature transition to a superconducting phase in boron-doped silicon films grown on (001)-oriented silicon wafers
We report on a detailed analysis of the superconducting properties of
boron-doped silicon films grown along the 001 direction by Gas Immersion Laser
Doping. The doping concentration cB has been varied up to approx. 10 at.% by
increasing the number of laser shots to 500. No superconductivity could be
observed down to 40mK for doping level below 2.5 at.%. The critical temperature
Tc then increased steeply to reach 0.6K for cB = 8 at%. No hysteresis was found
for the transitions in magnetic field, which is characteristic of a type II
superconductor. The corresponding upper critical field Hc2(0) was on the order
of 1000 G, much smaller than the value previously reported by Bustarret et al.
in Nature (London) 444, 465 (2006).Comment: 4 pages including 4 figures, submitted to PRB-Rapid Communicatio
- âŠ