3,661 research outputs found
Performance of GPS/GPRS tracking devices improves with increased fix interval and is not affected by animal deployment
The use of GPS tracking technologies has revolutionized the study of animal movement providing unprecedentedly detailed
information. The characterization of GPS accuracy and precision under different conditions is essential to correctly identify the
spatial and temporal resolution at which studies can be conducted. Here, we examined the influence of fix acquisition interval and
device deployment on the performance of a new GPS/GSM solar powered device. Horizontal and vertical accuracy and precision of
locations were obtained under different GPS fix acquisition intervals (1min, 20 min and 60 min) in a stationary test. The test devices
were deployed on pre-fledgling white storks (Ciconia ciconia) and we quantified accuracy and precision after deployment while
controlling for bias caused by variation in habitat, topography, and animal movement. We also assessed the performance of GPSError,
a metric provided by the device, at identifying inaccurate locations (> 10 m). Average horizontal accuracy varied between 3.4
to 6.5 m, and vertical accuracy varied between 4.9 to 9.7 m, in high (1 min) and low frequency (60 min) GPS fix intervals. These
values were similar after the deployment on white storks. Over 84% of GPS horizontal positions and 71% of vertical positions had
less than 10m error in accuracy. Removing 3% of data with highest GPS-Error eliminated over 99% of inaccurate positions in high
GPS frequency intervals, but this metric was not effective in the low frequency intervals. We confirmed the suitability of these
devices for studies requiring horizontal and vertical accuracies of 5-10m. For higher accuracy data, intensive GPS fix intervals
should be used, but this requires more sophisticated battery management, or larger batteries and devicesinfo:eu-repo/semantics/publishedVersio
Comparative Study of the Response of Kinematical Variables from the Hip and the Center of Mass in Butterfliers
The aim of this study was to compare the intracyclic variation of kinematical variables from the
hip and the center of mass (CM) with the purpose to assess if the analysis of kinematical
variables of the hip might replace the study of the kinematical variables of the CM. Seven
Portuguese male swimmers of national and intemational levei were studied. Each swimmer
performed 3 sets of3x25 meters, at a constant velocity and as close as possible to the maximum,
using exclusively frontal inspiration cycles, lateral inspiration cycles and non-inspiratory cycles
in each set. Two pairs of cameras were used to create "dual media" images. Another cam era was
set behind an underwater window in the endwall. One last camera was placed above the water
surface. The study comprised the analysis of complete stroke cycles in buttert1y using the "Ariel
Performance Analysis System" from Ariel Dynamics Inc. Some of the correlations between the
maximal vertical amplitude of displacement of the hip and the CM didn't present significant
values. AlI the correlations between the horizontal velocity and horizontal acceleration of the
hip and the CM were significant in all breathing models. However, only one swimmer presented
in both cases r>=O.95. So, apparently, the hip does not represent properly the intracyclic
variations ofthe kinematical variables ofthe CM.info:eu-repo/semantics/publishedVersio
Análise dos Fatos utilizados no 13º Campeonato do Mundo FINA
Para nadar mais rápido, é necessário aumentar a propulsão e diminuir o arrasto. Para o caso,
os fatos de natação de poliuretano podem ter desempenhado um papel importante (Marinho et
al., 2009). Com este estudo pretende-se descrever a distribuição dos diferentes modelos de fatos
de natação usados pelos nadadores durante todas as finais do 13º Campeonato do Mundo de
natação, realizado em Roma e assim perceber as preferências dos nadadores de elevado nível desportivo
13th FINA world Championship: analysis of swimsuits used by elite male swimmers
The polyurethane swimsuits has become the notice
around the pools in the past couple years. A better body position
and the reducing of drag are believed to be some of the reasons that allow
the swimmers wearing these swimsuits to go faster (Kainuma et al.,
2009). The purpose of this study was to verify the distribution of different
swimsuits used by male swimmers during the finals at the last world
championships being held at Rome in 200
Conhecendo o IAF do cafeeiro arábica através do índice de vegetação por diferença normalizada
O objetivo deste trabalho foi relacionar a série temporal do Índice de Área Foliar (IAF) estimado pelo método proposto por Barbosa et al. (2012) ao índice de vegetação por diferença normalizada (NDVI) adequando um modelo de determinação do IAF através de dados de NDVI coletados em um cafezal na região de Lavras, sul de Minas Gerais. Para isso foi realizado o estudo em cafezal no campus da Universidade Federal de Lavras (UFLA) no período de fevereiro de 2014 a fevereiro de 2015 onde trinta plantas de Coffea arabica L, cv Catuaí IAC 144 foram avaliadas mensalmente com medições de altura do ramo ortotrópico e comprimento de plagiotrópicos em 5 posições na copa para estimativa do IAF, enquanto as avaliações de NDVI foram realizadas semanalmente em três posições distintas da planta. Dados mensais de precipitação (mm- Prec) e temperatura média do ar (°C- Tm) também foram coletados. Os valores de cada variável foram submetidos à análise de correlação (r). A série temporal demonstra que o IAF varia em função da temperatura e precipitação. O modelo de regressão exponencial foi o mais adequado para determinar os valores de IAF em função do NDVI. As correlações do IAF com o NDVI variam em função da posição da medida de NDVI da planta. A série temporal do IAF é uma variável útil nas práticas de manejo, enquanto NDVI pode ser utilizado para determinar o IAF em plantas de café
Role of Charm Factory in Extracting CKM-Phase Information via B --> DK
In this paper we study the impact of data that can be obtained from a Charm
Factory on the determination of the CKM parameter gamma from decays of the form
B -> D0 K where the D0 decays to specific inclusive and exclusive final states.
In particular, for each exclusive final state , the charm factory can
determine the strong phase difference between D0-> f and D0-bar -> f by
exploiting correlations in psi(3770)-> D0 D0-bar. This provides crucial input
to the determination of gamma via the interference of B+- -> K+- D0 -> f with
B+- -> K+- D0-bar -> f. We discuss how the method may be generalized to
inclusive final states and illustrate with a toy model how such methods may
offer one of the best means to determine gamma with 10^8-10^9 B-mesons.Comment: 12 pages, 7 figures, Version 2: Fixed typos; add reference; Version
3: fixed latex glitc
Observation of the complete rupture of a buried polymer layer by off-specular neutron reflectometry
We have used off-specular neutron reflectometry to study the rupture of a thin, deuterated polystyrene layer confined between a silicon substrate and a thick poly(methyl methacrylate) upper layer. After total rupture of the buried layer, the resulting roughness at the interface that controls the total reflection edge gives rise to Yoneda off-specular scattering. This hypothesis is confirmed by specular reflectivity data that can be fitted to an effective error function subsequent to the rupture of the buried layer. The observed increase in the Yoneda peak intensities, integrated along the path of constant momentum transfer qz, can be directly related to the formation of an interdigitated structure upon rupture of the buried layer. A distorted-wave Born approximation is used to quantitatively simulate the form of the off-specular data in terms of an equivalent error function, with fitting parameters in good agreement with the physical properties of the samples and key experimental results
Identifying and prioritising services in European terrestrial and freshwater ecosystems
Ecosystems are multifunctional and provide humanity with a broad array of vital services. Effective management of services requires an improved evidence base, identifying the role of ecosystems in delivering multiple services, which can assist policy-makers in maintaining them. Here, information from the literature and scientific experts was used to systematically document the importance of services and identify trends in their use and status over time for the main terrestrial and freshwater ecosystems in Europe. The results from this review show that intensively managed ecosystems contribute mostly to vital provisioning services (e.g. agro-ecosystems provide food via crops and livestock, and forests provide wood), while semi-natural ecosystems (e.g. grasslands and mountains) are key contributors of genetic resources and cultural services (e.g. aesthetic values and sense of place). The most recent European trends in human use of services show increases in demand for crops from agro-ecosystems, timber from forests, water flow regulation from rivers, wetlands and mountains, and recreation and ecotourism in most ecosystems, but decreases in livestock production, freshwater capture fisheries, wild foods and virtually all services associated with ecosystems which have considerably decreased in area (e.g. semi-natural grasslands). The condition of the majority of services show either a degraded or mixed status across Europe with the exception of recent enhancements in timber production in forests and mountains, freshwater provision, water/erosion/natural hazard regulation and recreation/ecotourism in mountains, and climate regulation in forests. Key gaps in knowledge were evident for certain services across all ecosystems, including the provision of biochemicals and natural medicines, genetic resources and the regulating services of seed dispersal, pest/disease regulation and invasion resistance
Urinary Metabolic Phenotyping Reveals Differences in the Metabolic Status of Healthy and Inflammatory Bowel Disease (IBD) Children in Relation to Growth and Disease Activity.
Growth failure and delayed puberty are well known features of children and adolescents with inflammatory bowel disease (IBD), in addition to the chronic course of the disease. Urinary metabonomics was applied in order to better understand metabolic changes between healthy and IBD children.
21 Pediatric patients with IBD (mean age 14.8 years, 8 males) were enrolled from the Pediatric Gastroenterology Outpatient Clinic over two years. Clinical and biological data were collected at baseline, 6, and 12 months. 27 healthy children (mean age 12.9 years, 16 males) were assessed at baseline. Urine samples were collected at each visit and subjected to ¹H Nuclear Magnetic Resonance (NMR) spectroscopy.
Using ¹H NMR metabonomics, we determined that urine metabolic profiles of IBD children differ significantly from healthy controls. Metabolic differences include central energy metabolism, amino acid, and gut microbial metabolic pathways. The analysis described that combined urinary urea and phenylacetylglutamine-two readouts of nitrogen metabolism-may be relevant to monitor metabolic status in the course of disease.
Non-invasive sampling of urine followed by metabonomic profiling can elucidate and monitor the metabolic status of children in relation to disease status. Further developments of omic-approaches in pediatric research might deliver novel nutritional and metabolic hypotheses
Getting beta-alpha without penguins
Oscillation effects in B0 -> Ks D0 and related processes are considered to
determine delta=beta-alpha+pi. We suggest that D0 decays to CP eigenstates used
in concert with inclusive D0 decays provide a powerful method for determining
delta cleanly i.e. without any complication from penguin processes. The CP
asymmetry is expected to be <=40% for D0 decays to non-CP eigenstates and <=80%
for decays to CP eigenstates. This method can lead to a fairly accurate
determination of delta with O(10^8-10^9) B-mesons.Comment: 4 pages 1 figure; Version 2: minor changes; references added; Some
changes in response to Referee Comment
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