816 resultados para Composite Physical Function Scale
Resumo:
Recently a new method to set the scale in lattice gauge theories, based on the gradient flow generated by the Wilson action, has been proposed, and the systematic errors of the new scales t0 and w0 have been investigated by various groups. The Wilson flow provides also an interesting alternative smoothing procedure particularly useful for the measurement of the topological charge as a pure gluonic observable. We show the viability of this method for N=1 supersymmetric Yang-Mills theory by analysing the configurations produced by the DESY-Muenster Collaboration. The relation between the scale and the topological charge has been investigated showing a strong correlation. We have found that the scale has a linear dependence on the topological charge, the slope of which increases decreasing the volume and the gluino mass. Moreover we have investigated this dependence as a function of the reference parameter used to define the scale: the tuning of this parameter turns out to be fundamental for a more reliable scale setting. Similar conclusions hold for the Sommer parameter r0.
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Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a ’control valve’ on ocean–atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air–sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and 14C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the biological export of carbon and increases in deep-ocean ventilation via southern-sourced water masses. These findings demonstrate how the Southern Ocean’s ’organic carbon pump’ has exerted a tight control on atmospheric CO2, and thus global climate, specifically via a synergy of both physical and biological processes.
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Research has shown that physical activity serves a preventive function against the development of several major chronic diseases. However, studying physical activity and its health benefits is difficult due to the complexity of measuring physical activity. The overall aim of this research is to contribute to the knowledge of both correlates and measurement of physical activity. Data from the Women On The Move study were used for this study (n = 260), and the results are presented in three papers. The first paper focuses on the measurement of physical activity and compares an alternate coding method with the standard coding method for calculating energy expenditure from a 7-day activity diary. Results indicate that the alternative coding scheme could produce similar results to the standard coding in terms of total activity expenditure. Even though agreement could not be achieved by dimension, the study lays the groundwork for a coding system that saves considerable amount of time in coding activity and has the ability to estimate expenditure more accurately for activities that can be performed at varying intensity levels. The second paper investigates intra-day variability in physical activity by estimating the variation in energy expenditure for workers and non-workers and identifying the number of days of diary self-report necessary to reliably estimate activity. The results indicate that 8 days of activity are needed to reliably estimate total activity for individuals who don't work and 12 days of activity are needed to reliably estimate total activity for those who work. Days of diary self-report required by dimension for those who don't work range from 6 to 16 and for those who work from 6 to 113. The final paper presents findings on the relationship between daily living activity and Type A behavior pattern. Significant findings are observed for total activity and leisure activity with the Temperament Scale summary score. Significant findings are also observed for total activity, household chores, work, leisure activity, exercise, and inactivity with one or more of the individual items on the Temperament Scale. However, even though some significant findings were observed, the overall models did not reveal meaningful associations. ^
Resumo:
Ray (1998) developed measures of input- and output-oriented scale efficiency that can be directly computed from an estimated Translog frontier production function. This note extends the earlier results from Ray (1998) to the multiple-output multiple input case.
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The Surgeon General recommends preschoolers 3-5 years old accumulate 60 minutes of moderate-to-vigorous physical activity (MVPA) per day. However, there is limited data measuring physical activity (PA) and MVPA amongst this population. The purpose of this cross-sectional study is to determine the validity, reliability, and feasibility of using MVP 4 Function Walk4Life digital pedometers (MVP-4) in measuring MVPA among preschoolers using the newly modified direct observational technique, System for Observing Fitness Instruction Time-Preschool Version (SOFIT-P) as the gold standard. An ethnically diverse population of 3-5 year old underserved children were recruited from two Harris County Department of Education (HCDE) Head Start centers. For 2 days at baseline and 2 days at post-test, 75 children enrolled wore MVP-4 pedometers for approximately 6-hours per observation day and were observed using SOFIT-P during predominantly active times. Statistical analyses used Pearson "r" correlation coefficients to determine mean minutes of PA and MVPA, convergent and criterion validity, and reliability. Significance was set at p = <0.05. Feasibility was determined through process evaluation information collected during this study via observations from data collectors and teacher input. Results show mean minutes of PA and MVPA ranged between 30-42 and 11-14 minutes, respectively. Convergent validity comparing BMI percentiles with MVP-4 PA outcomes show no significance at pre-test; however, each measurement at post-test showed significance for MVPA (p = 0.0247, p = 0.0056), respectively. Criterion validity comparing percent MVPA time between SOFIT-P and MVP-4 pedometers was determined; however, results deemed insufficient due to inconsistency in observation times while using the newly developed SOFIT-P. Reliability measures show no significance at pre-test, yet show significant results for all PA outcomes at post-test (p = 0.001, p = 0.001, p = 0.0010, p = 0.003), respectively. Finally, MVP-4 pedometers lacked feasibility due to logistical barriers in design. Researchers feel the significant results at post-test are secondary to increased familiarity and more accurate placement of pedometers across time. Researchers suggest manufacturers of MVP-4 pedometers further modify the instrument for ease of use with this population, following which future studies ought to determine validity using objective measures or all-day direct observation techniques.^
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The European Programme for Ice Coring in Antarctica includes a comprehensive pre-site survey on the inland ice plateau of Dronning Maud Land, Antarctica. The German glaciological programme during the 1997/98 field season was carried out along a 1200 km traverse on Amundsenisen and involved sampling the snow cover in pits and by shallow firn cores. This paper focuses on the accumulation studies. The cores were dated by dielectric-profiling and continuous-flow analysis. Distinct volcanogenic peaks and seasonal signals in the profiles served to establish a depth time-scale. The eruptions of Krakatoa, Tambora, an unknown volcano, Kuwae and El Chichon are well-documented in the ice. Variations of the accumulation rates over different times were inferred from the depth time-scales. A composite record of accumulation rates for the last 200 years was produced by stacking 12 annually resolved records. According to this, accumulation rates decreased in the 19th century and increased in the 20th century. The recent values are by no means extraordinary, as they do not exceed the values at the beginning of the 19th century. Variations in accumulation rates are most probably linked to temperature variations indicated in d18O records from Amundsenisen.
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Multiple holes were cored at Ocean Drilling Program Leg 178 Sites 1098 and 1099 in two subbasins of the Palmer Deep in order to recover complete and continuous records of sedimentation. By correlating measured properties of cores from different holes at a site, we have established a common depth scale, referred to as the meters composite depth scale (mcd), for all cores from Site 1098. For Site 1098, distinct similarities in the magnetic susceptibility records obtained from three holes provide tight constraints on between-hole correlation. Additional constraints come from lithologic features. Specific intervals from other data sets, particularly gamma-ray attenuation bulk density, magnetic intensity, and color reflectance, contain distinctive anomalies that correlate well when placed into the preferred composite depth scale, confirming that the scale is accurate. Coring in two holes at Site 1099 provides only a few meters of overlap. None of the data sets within this limited overlap region provide convincing correlations. Thus, the preferred composite depth scale for Site 1099 is the existing depth scale in meters below seafloor (mbsf).
Resumo:
We present new revised composite depth scales for Ocean Drilling Program Leg 198 Sites 1209, 1210, and 1211, drilled at Shatsky Rise in the western Pacific Ocean. Reinterpretation of high-resolution physical property data, with the main focus on magnetic susceptibility as the primary parameter for hole-to-hole correlation, revealed that the shipboard composite records had to be revised below 124.87 meters composite depth (mcd) for Site 1209, below 142.45 mcd for Site 1210, and below 88.64 mcd for Site 1211. The revised composite records comprise Paleogene and Cretaceous sediments at all three sites. As a result of the additional adjustments, the revised mcd records of Sites 1209 and 1210 are 13.48 and 2.69 m longer than the original spliced records, respectively. The original splice of Site 1211 has undergone minor adjustments only to match those of Sites 1209 and 1210. Moreover, detailed correlation of sections outside the new spliced records enable samples already taken to be placed into the new revised composite depth scale.
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A high-resolution stratigraphy is essential toward deciphering climate variability in detail and understanding causality arguments of events in earth history. Because the highly dynamic middle to late Eocene provides a suitable testing ground for carbon cycle models for a waning warm world, an accurate time scale is needed to decode climate-driving mechanisms. Here we present new results from ODP Site 1260 (Leg 207) which covers a unique expanded middle Eocene section (magnetochrons C18r to C20r, late Lutetian to early Bartonian) of the tropical western Atlantic including the chron C19r transient hyperthermal event and the Middle Eocene Climate Optimum (MECO). To establish a detailed cyclostratigraphy we acquired a distinctive iron intensity records by XRF scanning Site 1260 cores. We revise the shipboard composite section, establish a cyclostratigraphy and use the exceptional eccentricity modulated precession cycles for orbital tuning. The new astrochronology revises the age of magnetic polarity chrons C19n to C20n, validates the position of very long eccentricity minima at 40.2 and 43.0 Ma in the orbital solutions, and extends the Astronomically Tuned Geological Time Scale back to 44 Ma. For the first time the new data provide clear evidence for an orbital pacing of the chron C19r event and a likely involvement of the very long eccentricity cycle contributing to the evolution of the MECO.
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The first experiment of the ECOMARGE programme (ECOsystèmes de MARGE continentale) was initiated in 1983-1984, in the Gulf of Lions (northwestern Mediterranean Sea). The objectives of the ECOMARGE-I experiment were: to quantify the transfer of particulate matter, in general, and of organic carbon, in particular, from its introduction to and formation in the waters of the continental shelf-to its consumption or sedimentation on the shelf or its transfer to the slope and deep sea; and to understand the processes involved in that transfer, consumption and sedimentation together with their variability in space and time. The results of that experiment, from 1983 to 1988, are presented in this Special Issue. The highlights of the results are summarised in this paper. These results indicate that, of the particles formed in the waters of the continental shelf and those introduced by rivers, some are deposited as sediments on the shelf. A portion is transported offshore, however, to the slope and deep sea. The Rho^ne River, in the northeastern part of the study area, is the major source of continental material; this is transported to sea in a benthic nepheloid layer and, mostly, alongshore to the southwest. Here, it largely leaves the shelf through the canyons, especially the Lacaze-Duthiers Canyon. In the offshore waters, particle concentrations and distributions show surficial, intermediate and benthic nepheloid layers. These turbid structures increase towards the southwest, corresponding to the seaward shift of the front between the coastal waters and the Liguro-Provençal cyclonic gyre, a major forcing function in the Gulf of Lions. Considering the source and fate of particles (largely biogenic from the euphotic zone and abiogenic from deeper waters) a layered system is described, which is emphasized by the concentrations of natural and artificial elements and compounds. Of the flux of particles to the Lacaze-Duthiers Canyon, on a decadal scale, about 30% (as a minimum) is estimated to be stored as sediment; the remainder is transported down-canyon, towards the deep sea. The temporal variability of processes affecting this net seaward transport, of both biogenic and abiogenic material, is from hours, days to seasonal, and probably interannual, time scales. The response of the system to these variations is rapid, with pulses of increased discharge of particles from the adjacent shelf being detected in sediment traps in the Lacaze-Duthiers Canyon in less than 16 days (the temporal resolution of the traps). Based upon the study of tracers of particulate matter and environmental factors (i.e. river discharge and climatic conditions), it appears that the contribution from the Rho^ne River and its adjacent area is maximal during the winter; at this time, the flow of the Liguro-Provençal Current also increases. In contrast, the maximum relative contribution of the adjacent southwesterly area to the flux in the Lacaze-Duthiers Canyon occurs in summer, during storm events.
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Deep Sea Drilling Project Site 577 on Shatsky Rise (North Pacific Ocean) recovered a series of cores at three holes that contain calcareous nannofossil ooze of latest Cretaceous (late Maastrichtian) through early Eocene age. Several important records have been generated using samples from these cores, but the stratigraphy has remained outdated and confusing. Here we revise the stratigraphy at Site 577. This includes refining several age datums, realigning cores in the depth domain, and placing all stratigraphic markers on a current time scale. The work provides a template for appropriately bringing latest Cretaceous and Paleogene data sets at old drill sites into current paleoceanographic literature for this time interval. While the Paleocene Eocene Thermal Maximum (PETM) lies within core gaps at Holes 577* and 577A, the sedimentary record at the site holds other important events and remains crucially relevant to understanding changes in oceanographic conditions from the latest Cretaceous through early Paleogene.
Resumo:
We present composite depth scales for the multiply cored intervals from Sites 1150 and 1151. These new depth scales place coeval strata recovered in cores from different holes at a single site into a common stratigraphic framework. At Site 1150, double coring between Holes 1150A and 1150B occurred over only a short interval between ~703 and 713 meters below seafloor (mbsf), but this is sufficient to tie the upper portion of the stratigraphic section cored in Hole 1150A to the lower portion cored in Hole 1150B. The upper ~100 m of the sedimentary section at Site 1151 was double cored with the advanced piston corer and partially cored with the rotary core barrel, resulting in the complete recovery of this interval. The composite depth scales were constructed using Splicer software to vertically adjust the relative depths of various cores from one hole to the depths from another hole so as to align distinct physical properties measured on cores. The magnetic susceptibility data was the physical property most easily correlated between holes, and therefore primarily used to create a composite depth scale and spliced stratigraphic section. The spliced section is a continuous stratigraphic section constructed from representative cored intervals from the holes at a site. Both the splice and the composite depth scale can be applied to other data sets from Site 1151 to provide a stratigraphically continuous and laterally consistent basis for interpreting lithologic features or data sets. The resulting composite scale showed a 30% improvement in correlation of the magnetic susceptibility data relative to the original mbsf depth scale, and comparable improvement when applied to the other data sets.