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Data, Metrics and Monitoring in CGIAR - a strategic study
This document contains the final report of the Panel together with the ISPC commentary. The Panel Report presents an analysis of the current activities within CGIAR concerning data, metrics and indicators, and offers a series of recommendations to address the key issues and challenges identified
Connecting speciesâ geographical distributions to environmental variables: range maps versus observed points of occurrence
Connecting the geographical occurrence of a species with underlying environmental variables is fundamental for many analyses of life history evolution and for modeling species distributions for both basic and practical ends. However, raw distributional information comes principally in two forms: points of occurrence (specific geographical coordinates where a species has been observed), and expert-prepared range maps. Each form has potential short-comings: range maps tend to overestimate the true occurrence of a species, whereas occurrence points (because of their frequent non-random spatial distribution) tend to underestimate it. Whereas previous comparisons of the two forms have focused on how they may differ when estimating species richness, less attention has been paid to the extent to which the two forms actually differ in their representation of a speciesâ environmental associations. We assess such differences using the globally distributed avian order Galliformes (294 species). For each species we overlaid range maps obtained from IUCN and point-of-occurrence data obtained from GBIF on global maps of four climate variables and elevation. Over all species, the median difference in distribution centroids was 234 km, and median values of all five environmental variables were highly correlated, although there were a few species outliers for each variable. We also acquired speciesâ elevational distribution mid-points (mid-point between minimum and maximum elevational extent) from the literature; median elevations from point occurrences and ranges were consistently lower (median â420 m) than mid-points. We concluded that in most cases occurrence points were likely to produce better estimates of underlying environmental variables than range maps, although differences were often slight. We also concluded that elevational range mid-points were biased high, and that elevation distributions based on either points or range maps provided better estimates
Effects of Longitudinal Bending Stiffness of forefoot rocker profile shoes on ankle kinematics and kinetics
INTRODUCTION: Rocker profile shoes with a proximally placed apex are currently one of the most prescribed shoe modifications for treatment and prevention of lower leg deficits. Three geometrical rocker design parameters apex position (AP), apex angle (AA) and rocker radius (RR) influence both plantar pressure redistribution and kinetic and kinematic alterations of the lower leg. In addition, longitudinal bending stiffness (LBS) of the outsole influences these parameters as well. This study aims to investigate the effects of the LBS in combination with different forefoot radii of rocker shoes on kinematics and kinetics of the lower limb. METHODS: 10 participants walked in standard shoes and six experimental shoe conditions with high and low LBS and three different forefoot rocker radii with the same (proximal) AP and AA. Lower extremity kinematics and kinetics were collected while walking on an instrumented treadmill at preferred walking speed and analysed with a repeated measures ANOVA and Statistical Parametric Mapping (SPM) (α = .05; post hoc α = .05/6). RESULTS: SPM analyses revealed no significant differences for LBS and interaction LBS*RR for most research variables in terminal stance (ankle angle, ankle moment, ankle power, foot-to-horizontal angle, shank-to-vertical angle, external ankle moment, ground reaction force angle). A significant LBS effect was found for anterior-posterior position of the centre of pressure during pre-swing and peak ankle dorsiflexion angle. No relevant significant differences were found in spatio-temporal parameters and total work at the ankle between low and high LBS. CONCLUSION: This study showed that longitudinal bending stiffness does not affect the biomechanical working mechanism of rocker profile shoes as long as toe plantarflexion is restricted. Providing that the forefoot rocker radius supports at least a normal foot-to-horizontal angle at toe-off, there is no reason to increase sole stiffness to change ankle kinematics and kinetics
Effects of rocker radii with two longitudinal bending stiffnesses on plantar pressure distribution in the forefoot
INTRODUCTION: Outsole parameters of the shoe can be adapted to offload regions of pain or region of high pressures. Previous studies already showed reduced plantar pressures in the forefoot due to a proximally placed apex position and higher longitudinal bending stiffness (LBS). The aim of this study was to determine the effect of changes in rocker radii and high LBS on the plantar pressure profile during gait. METHOD: 10 participants walked in seven shoe conditions of which one control shoe and six rocker shoes with small, medium and large rocker radii and low and high longitudinal bending stiffness. Pedar in-shoe plantar pressure measuring system was used to quantify plantar pressures while walking on a treadmill at self-selected walking speed. Peak plantar pressure, maximum mean pressure and force-time integral were analyzed with Generalized Estimated Equation (GEE) and Tukey post hoc correction (α = .05). RESULTS: Significantly lower plantar pressures were found in the first toe, toes 2-5, distal and proximal forefoot in all rocker shoe conditions as compared to the control shoe. Plantar pressures in the first toe and toes 2-5 were significantly lower in the small radius compared to medium and large radii. For the distal forefoot both small and medium radii significantly reduced plantar pressure compared to large radii. Low LBS reduced plantar pressure at the first toe significantly compared to high LBS independent of the rocker radius. Plantar pressures in the distal forefoot and toes 2-5 were lower in high LBS compared to low LBS. CONCLUSION: Manipulation of the rocker radius and LBS can effectively reduce peak plantar pressures in the forefoot region during gait. In line with previous studies, we showed that depending on the exact target location for offloading, different combinations of rocker radius and LBS need to be adopted to maximize treatment effects
Trophic interactions will expand geographically but be less intense as oceans warm
Interactions among species are likely to change geographically due to climate-driven
species range shifts and in intensity due to physiological responses to increasing temperatures.
Marine ectotherms experience temperatures closer to their upper thermal
limits due to the paucity of temporary thermal refugia compared to those available to
terrestrial organisms. Thermal limits of marine ectotherms also vary among species
and trophic levels, making their trophic interactions more prone to changes as oceans
warm. We assessed how temperature affects reef fish trophic interactions in the
Western Atlantic and modeled projections of changes in fish occurrence, biomass,
and feeding intensity across latitudes due to climate change. Under ocean warming,
tropical reefs will experience diminished trophic interactions, particularly herbivory
and invertivory, potentially reinforcing algal dominance in this region. Tropicalization
events are more likely to occur in the northern hemisphere, where feeding by tropical
herbivores is predicted to expand from the northern Caribbean to extratropical reefs.
Conversely, feeding by omnivores is predicted to decrease in this area with minor increases
in the Caribbean and southern Brazil. Feeding by invertivores declines across
all latitudes in future predictions, jeopardizing a critical trophic link. Most changes
are predicted to occur by 2050 and can significantly affect ecosystem functioning,
causing dominance shifts and the rise of novel ecosystems.Postprint6,86
Adiabatically changing the phase-space density of a trapped Bose gas
We show that the degeneracy parameter of a trapped Bose gas can be changed
adiabatically in a reversible way, both in the Boltzmann regime and in the
degenerate Bose regime. We have performed measurements on spin-polarized atomic
hydrogen in the Boltzmann regime demonstrating reversible changes of the
degeneracy parameter (phase-space density) by more than a factor of two. This
result is in perfect agreement with theory. By extending our theoretical
analysis to the quantum degenerate regime we predict that, starting close
enough to the Bose-Einstein phase transition, one can cross the transition by
an adiabatic change of the trap shape.Comment: 4 pages, 3 figures, Latex, submitted to PR
Soil quality and constraints in global rice production
We assessed soil quality in global rice production areas with the Fertility Capability Soil Classification (FCC) system adjusted to match the harmonized world soil database, established by the Food and Agriculture Organization and the International Institute for Applied Systems Analysis. We computed the distribution of 20 soil constraints, and used these to categorize soils as 'good', 'poor', 'very poor', or 'problem soil' for rice production. These data were then combined with data of global rice distribution to determine soil quality in the main rice production systems around the world. Most rice is grown in Asia (143.4. million. ha), followed by Africa (10.5. million. ha) and the Americas (7.2. million. ha). Globally, one-third of the total rice area is grown on very poor soils, which includes 25.6. million. ha of irrigated rice land, 18.5. million. ha in rainfed lowlands, and 7.5. million. ha of upland rice. At least 8.3. million. ha of rice is grown on problem soils, including saline, alkaline/sodic, acid-sulfate, and organic soils. Asia has the largest percentage of rice on good soils (47%) whereas rice production on good soils is much less common in the Americas (28%) and accounts for only 18% in Africa. The most common soil chemical problems in rice fields are very low inherent nutrient status (35.8. million. ha), very low pH (27.1. million. ha), and high P fixation (8.1. million. ha); widespread soil physical problems especially severe in rainfed environments are very shallow soils and low water-holding capacity. The results of the analysis can be used to better target crop improvement research, plant breeding, and the dissemination of stress-specific tolerant varieties and soil management technologies. © 2014 Elsevier B.V.S.M. Haefele, A. Nelson, R.J. Hijman
RehabMove 2018: THE IMPLEMENTATION OF VO2 KINETICS TO EVALUATE TRAINING EFFECTS IN CANCER PATIENTS
PURPOSE: Oxygen uptake (VÌO2) kinetics can be used to measure exercise capacity. A constant work rate (CWR) test at moderate intensity measuring VÌO2 on-kinetics may be more suitable for a deconditioned patient population and a valuable source of information on training effects in addition to the regular exercise tests. The main goal of this study was to compare the sensitivity of VÌO2 on-kinetics during a rest-to-submaximal exercise transition to the regular variables measured in an incremental cardiopulmonary exercise test (CPET): ventilatory threshold (VT), VÌO2peak and peak work rate (WRpeak) to exercise induced changes, and to evaluate the usefulness of VÌO2 on-kinetics in determining an improved exercise capacity with respect to CPET in cancer patients.
METHODS: Ten cancer patients (7 females) with a variety of cancer types aged between 39 and 64 years were enrolled in a 12-week rehabilitation program, in which they performed combined cycle-ergometer and strength training for two times a week. At initial and final evaluations, VÌO2 on-kinetics were measured breath-by-breath during a CWR test of moderate intensity, and VÌO2peak and VT were measured with a CPET.
RESULTS: Comparisons between pre- and post-intervention showed large effect sizes for VÌO2peak (r = .59) and oxygen uptake at VT (r = .56). VÌO2 on-kinetics did not change after the training program.
CONCLUSION: The current results suggest that VÌO2 on-kinetics is not more sensitive to exercise-induced adaptations compared to VÌO2peak and VT. However, VÌO2 on-kinetics did increase in eight of the ten subjects, and can serve as a source of information on training progress, especially when other information is lacking due to a non-maximal CPET or an unreliable VT
Genetic diversity, population structure, and genetic correlation with climatic variation in chickpea (Cicer arietinum) landraces from Pakistan
Chickpea (Cicer arietinum L.) production in arid regions, such as those predominant in Pakistan, faces immense challenges of drought and heat stress. Addressing these challenges is made more difficult by the lack of genetic and phenotypic characterization of available cultivated varieties and breeding materials. Genotyping-by-sequencing offers a rapid and cost-effective means to identify genome-wide nucleotide variation in crop germplasm. When combined with extended crop phenotypes deduced from climatic variation at sites of collection, the data can predict which portions of genetic variation might have roles in climate resilience. Here we use 8113 single nucleotide polymorphism markers to determine genetic variation and compare population structure within a previously uncharacterized collection of 77 landraces and 5 elite cultivars, currently grown in situ on farms throughout the chickpea growing regions of Pakistan. The compiled landraces span a striking aridity gradient into the Thal Desert of the Punjab. Despite low levels of variation across the collection and limited genetic structure, we found some differentiation between accessions from arid, semiarid, irrigated, and coastal areas. In a subset of 232 markers, we found evidence of differentiation along gradients of elevation and isothermality. Our results highlight the utility of exploring large germplasm collections for nucleotide variation associated with environmental extremes, and the use of such data to nominate germplasm accessions with the potential to improve crop drought tolerance and other environmental traits
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