bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aerobic fitness and obesity: relationship to cerebral white matter integrity in the brain of active and sedentary older adults
Authors: Marks BL , Katz LM , Styner M , Smith JK 
Published: June 2010

ObjectiveAerobic fitness (VO2peak) and obesity risk (OR) may impact brain health. This study examined hemispheric and segment specific relationships between VO2peak, OR and cerebral white-matter (CWM) integrity in the cingulum brain region in healthy older adults.MethodsFifteen subjects (66±6 years) completed VO2peak testing and MRI of the brain. OR was determined via body mass index (BMI) and abdominal girth. MRI analysis was performed with a structural 3D T1 MP-Rage and diffusion tensor imaging technique (DTI, 21 directions, repeated four times) on a 3.0 T MR imaging unit. CWM integrity indices, fractional anisotropy (FA) and mean diffusivity (MD), were computed from the tensors. The anterior, middle and posterior cingulum segments were analysed on both sides of the brain. Partial correlations (age and gender controlled) and standard multiple regressions were used to determine significant associations and unique contributions to CWM integrity.ResultsVO2peak was moderately related to FA in the left middle cingulum segment (r partial=0.573, p=0.041) and explained 28.5% of FA's total variance (p=0.10). Abdominal girth (r partial=−0.764, p=0.002) and BMI (r partial=−0.690, p=0.009) were inversely related to FA in the right posterior cingulum (RPC) segment. Abdominal girth and BMI uniquely explained 53.9% of FA's total variance (p=0.012) and 43.9% (p=0.040), respectively, in the RPC.ConclusionHigher aerobic fitness and lower obesity risk are related to greater CWM integrity but not in the same cingulum segments.
Sensor faults
Authors: Sharma Abhishek B. , Golubchik Leana , Govindan Ramesh 
Published: June 2010

Various sensor network measurement studies have reported instances of transient faults in sensor readings. In this work, we seek to answer a simple question: How often are such faults observed in real deployments? We focus on three types of transient faults, caused by faulty sensor readings that appear abnormal. To understand the prevalence of such faults, we first explore and characterize four qualitatively different classes of fault detection methods. Rule-based methods leverage domain knowledge to develop heuristic rules for detecting and identifying faults. Estimation methods predict “normal” sensor behavior by leveraging sensor correlations, flagging anomalous sensor readings as faults. Time-series-analysis-based methods start with an a priori model for sensor readings. A sensor measurement is compared against its predicted value computed using time series forecasting to determine if it is faulty. Learning-based methods infer a model for the “normal” sensor readings using training data, and then statistically detect and identify classes of faults.
We find that these four classes of methods sit at different points on the accuracy/robustness spectrum. Rule-based methods can be highly accurate, but their accuracy depends critically on the choice of parameters. Learning methods can be cumbersome to train, but can accurately detect and classify faults. Estimation methods are accurate, but cannot classify faults. Time-series-analysis-based methods are more effective for detecting short duration faults than long duration ones, and incur more false positives than the other methods. We apply these techniques to four real-world sensor datasets and find that the prevalence of faults as well as their type varies with datasets. All four methods are qualitatively consistent in identifying sensor faults, lending credence to our observations. Our work is a first step towards automated online fault detection and classification.
Effects of a Community-Based Intensive Motor Training Program Combined With Early Supported Discharge After Treatment in a Comprehensive Stroke Unit
Authors: Askim Torunn , Mørkved Siv , Engen Astrid , Roos Kerstin , Aas Tone , Indredavik Bent 
Published: June 2010

Background and Purpose—Increased amount of therapy seems to be beneficial for motor recovery after stroke. The primary aim of the present study was to evaluate the effect of a 4-week community-based intensive motor training program combined with early supported discharge after initial treatment in a comprehensive stroke unit on balance. Secondary aims were to evaluate the effect on other functional outcome measures.Methods—This was a single-blind, randomized, controlled trial with a 26-week follow-up. Sixty-two patients were recruited within 14 days after stroke and were randomly allocated to a standard treatment group (n=32) or to an intensive motor training group (n=30) receiving 3 sessions of physical therapy and a structured home exercise program in addition to standard treatment every week for the first 4 weeks after discharge from hospital. Primary outcome measure was Berg Balance Scale. Secondary measures were Barthel Index, Motor Assessment Scale, Step Test, 5-meter Walk Test, and Stroke Impact Scale.Results—The mean (SD) minutes of physical therapy per week was 171.0 (65.8) in the intensive motor training group vs 85.6(69.9) in the standard treatment group. There were no statistical significant differences between the groups on any measure at end of follow-up except for a trend toward higher Motor Assessment Scale score (P=0.059) and gait speed (P=0.095) in the intensive motor training group.Conclusion—In this randomized, controlled trial, a community-based intensive motor training program, doubling the amount of physical therapy during the first 4 weeks after discharge, did not show significant improvement of balance or any other functional outcomes.
Self-Adaptation of Mutation Operator and Probability for Permutation Representations in Genetic Algorithms
Authors: Serpell Martin , Smith James E. 
Published: June 2010

The choice of mutation rate is a vital factor in the success of any genetic algorithm (GA), and for permutation representations this is compounded by the availability of several alternative mutation operators. It is now well understood that there is no one “optimal choice”; rather, the situation changes per problem instance and during evolution. This paper examines whether this choice can be left to the processes of evolution via self-adaptation, thus removing this nontrivial task from the GA user and reducing the risk of poor performance arising from (inadvertent) inappropriate decisions. Self-adaptation has been proven successful for mutation step sizes in the continuous domain, and for the probability of applying bitwise mutation to binary encodings; here we examine whether this can translate to the choice and parameterisation of mutation operators for permutation encodings. We examine one method for adapting the choice of operator during runtime, and several different methods for adapting the rate at which the chosen operator is applied. In order to evaluate these algorithms, we have used a range of benchmark TSP problems. Of course this paper is not intended to present a state of the art in TSP solvers; rather, we use this well known problem as typical of many that require a permutation encoding, where our results indicate that self-adaptation can prove beneficial. The results show that GAs using appropriate methods to self-adapt their mutation operator and mutation rate find solutions of comparable or lower cost than algorithms with “static” operators, even when the latter have been extensively pretuned. Although the adaptive GAs tend to need longer to run, we show that is a price well worth paying as the time spent finding the optimal mutation operator and rate for the nonadaptive versions can be considerable. Finally, we evaluate the sensitivity of the self-adaptive methods to changes in the implementation, and to the choice of other genetic operators and population models. The results show that the methods presented are robust, in the sense that the performance benefits can be obtained in a wide range of host algorithms.
Tropical Oceanic Causes of Interannual to Multidecadal Precipitation Variability in Southeast South America over the Past Century*
Authors: Seager Richard , Naik Naomi , Baethgen Walter , Robertson Andrew , Kushnir Yochanan , Nakamura Jennifer , Jurburg Stephanie 
Published: June 2010

Abstract
Observations, atmosphere models forced by historical SSTs, and idealized simulations are used to determine the causes and mechanisms of interannual to multidecadal precipitation anomalies over southeast South America (SESA) since 1901. About 40% of SESA precipitation variability over this period can be accounted for by global SST forcing. Both the tropical Pacific and Atlantic Oceans share the driving of SESA precipitation, with the latter contributing the most on multidecadal time scales and explaining a wetting trend from the early midcentury until the end of the last century. Cold tropical Atlantic SST anomalies are shown to drive wet conditions in SESA. The dynamics that link SESA precipitation to tropical Atlantic SST anomalies are explored. Cold tropical Atlantic SST anomalies force equatorward-flowing upper-tropospheric flow to the southeast of the tropical heating anomaly, and the vorticity advection by this flow is balanced by vortex stretching and ascent, which drives the increased precipitation. The 1930s Pampas Dust Bowl drought occurred, via this mechanism, in response to warm tropical Atlantic SST anomalies. The atmospheric response to cold tropical Pacific SSTs also contributed. The tropical Atlantic SST anomalies linked to SESA precipitation are the tropical components of the Atlantic multidecadal oscillation. There is little evidence that the large trends over past decades are related to anthropogenic radiative forcing, although models project that this will cause a modest wetting of the climate of SESA. As such, and if the Atlantic multidecadal oscillation has shifted toward a warm phase, it should not be assumed that the long-term wetting trend in SESA will continue. Any reversal to a drier climate more typical of earlier decades would have clear consequences for regional agriculture and water resources.
Modulational Instabilities and Breaking Strength for Deep-Water Wave Groups
Authors: Galchenko Alina , Babanin Alexander V. , Chalikov Dmitry , Young I. R. , Hsu Tai-Wen 
Published: June 2010

AbstractProgression of nonlinear wave groups to breaking was studied numerically and experimentally. Evolution of such wave group parameters as a function of distance to breaking and modulation depth—the height ratio of the highest and the lowest waves in the group—was described. Numerical model results demonstrated good agreement with experimental results in describing the behavior of the distance to breaking and modulation depth as functions of initial wave steepness. It was shown that energy loss appears to be a function of the modulation depth at the breaking onset. Energy loss grows with modulation depth up to a certain threshold of the latter. It was also shown that breaking probability for wave groups with modulation depth below 2.2 is very low.
The Role of Mesoscale Eddies in the Remote Oceanic Response to Altered Southern Hemisphere Winds
Authors: Farneti Riccardo , Delworth Thomas L. 
Published: June 2010

Abstract
It has been suggested that a strengthening of the Southern Hemisphere winds would induce a more vigorous overturning through an increased northward Ekman flux, bringing more light waters into the oceanic basins and enhancing the upwelling of North Atlantic Deep Water in the Southern Ocean, thereby increasing ocean ventilation. Simulations from a coarse- and a fine-resolution version of a coupled model, subject to idealized wind stress changes in the Southern Ocean, are presented. In the fine-resolution eddy-permitting model, changes in poleward eddy fluxes largely compensate for the enhanced equatorward Ekman transport in the Southern Ocean. As a consequence, northward transport of light waters, pycnocline depth, Northern Hemisphere overturning, and Southern Ocean upwelling anomalies are much reduced compared with simulations in the coarse-resolution model with parameterized eddies. These results suggest a relatively weak sensitivity of present-day global ocean overturning circulation to the projected strengthening of the Southern Hemisphere winds.
AirCore: An Innovative Atmospheric Sampling System
Authors: Karion Anna , Sweeney Colm , Tans Pieter , Newberger Timothy 
Published: June 2010

Abstract
This work describes the AirCore, a simple and innovative atmospheric sampling system. The AirCore used in this study is a 150-m-long stainless steel tube, open at one end and closed at the other, that relies on positive changes in ambient pressure for passive sampling of the atmosphere. The AirCore evacuates while ascending to a high altitude and collects a sample of the ambient air as it descends. It is sealed upon recovery and measured with a continuous analyzer for trace gas mole fraction. The AirCore tubing can be shaped into a variety of configurations to accommodate any sampling platform; for the testing done in this work it was shaped into a 0.75-m-diameter coil. Measurements of CO2 and CH4 mole fractions in laboratory tests indicate a repeatability and lack of bias to better than 0.07 ppm (one sigma) for CO2 and 0.4 ppb for CH4 under various conditions. Comparisons of AirCore data with flask data from aircraft flights indicate a standard deviation of differences of 0.3 ppm and 5 ppb for CO2 and CH4, respectively, with no apparent bias. Accounting for longitudinal mixing, the expected measurement resolution for CO2 is 110 m at sea level, 260 m at 8000 m, and 1500 m at 20 000 m ASL after 3 h of storage, decreasing to 170, 390, and 2300 m, after 12 h. Validation tests confirm that the AirCore is a robust sampling device for many species on a variety of platforms, including balloons, unmanned aerial vehicles (UAVs), and aircraft.
A Method for Estimating the Turbulent Kinetic Energy Dissipation Rate from a Vertically Pointing Doppler Lidar, and Independent Evaluation from Balloon-Borne In Situ Measurements
Authors: O’Connor Ewan J. , Illingworth Anthony J. , Brooks Ian M. , Westbrook Christopher D. , Hogan Robin J. , Davies Fay , Brooks Barbara J. 
Published: June 2010

Abstract
A method of estimating dissipation rates from a vertically pointing Doppler lidar with high temporal and spatial resolution has been evaluated by comparison with independent measurements derived from a balloon-borne sonic anemometer. This method utilizes the variance of the mean Doppler velocity from a number of sequential samples and requires an estimate of the horizontal wind speed. The noise contribution to the variance can be estimated from the observed signal-to-noise ratio and removed where appropriate. The relative size of the noise variance to the observed variance provides a measure of the confidence in the retrieval. Comparison with in situ dissipation rates derived from the balloon-borne sonic anemometer reveal that this particular Doppler lidar is capable of retrieving dissipation rates over a range of at least three orders of magnitude.
This method is most suitable for retrieval of dissipation rates within the convective well-mixed boundary layer where the scales of motion that the Doppler lidar probes remain well within the inertial subrange. Caution must be applied when estimating dissipation rates in more quiescent conditions. For the particular Doppler lidar described here, the selection of suitably short integration times will permit this method to be applicable in such situations but at the expense of accuracy in the Doppler velocity estimates. The two case studies presented here suggest that, with profiles every 4 s, reliable estimates of ε can be derived to within at least an order of magnitude throughout almost all of the lowest 2 km and, in the convective boundary layer, to within 50%. Increasing the integration time for individual profiles to 30 s can improve the accuracy substantially but potentially confines retrievals to within the convective boundary layer. Therefore, optimization of certain instrument parameters may be required for specific implementations.
Sensitivity of the Simulated Tropical Cyclone Inner-Core Size to the Initial Vortex Size*
Authors: Xu Jing , Wang Yuqing 
Published: June 2010

Abstract
The multiply nested, fully compressible, nonhydrostatic tropical cyclone model version 4 (TCM4) is used to examine and understand the sensitivity of the simulated tropical cyclone (TC) inner-core size to its initial vortex size. The results show that although the simulated TC intensity at the mature stage is weakly dependent on the initial vortex size for the general settings, the simulated TC inner-core size is largely determined by the initial vortex size. The initial vortex size is critical to both the energy input from the ocean and the effectiveness of the inward angular momentum transport by the transverse circulation driven by eyewall convection and diabatic heating in spiral rainbands.
Strong outer winds in a storm with a large initial size lead to large entropy fluxes to a large radial extent outside the eyewall, favoring the development of active spiral rainbands. Latent heat released in spiral rainbands plays a key role in increasing the low-level radial inflow and accelerating tangential winds outside the eyewall, leading to outward expansion of tangential wind fields and thus increasing the inner-core size of the simulated storm. On the contrary, a storm with a small initial size has weaker outer winds and smaller surface entropy fluxes outside the eyewall and is accompanied by less active spiral rainbands and thus a much slower increase in the inner-core size. The effectiveness of the inward transport of absolute angular momentum to increase the tangential winds outside the eyewall is largely determined by the radial extent of the vertical absolute vorticity, which is shown to be higher in a large size vortex.
The relative importance of the initial vortex size and the environmental relative humidity (RH) to the TC inner-core size is also evaluated. It is found that the inner-core size of the simulated storm at the mature stage depends more heavily on the initial vortex size than on the initial RH of the environment.
Vertical Moist Thermodynamic Structure of the Madden–Julian Oscillation in Atmospheric Infrared Sounder Retrievals: An Update and a Comparison to ECMWF Interim Re-Analysis
Authors: Tian Baijun , Waliser Duane E. , Fetzer Eric J. , Yung Yuk L. 
Published: June 2010

Abstract
The large-scale vertical moist thermodynamic structure of the Madden–Julian oscillation (MJO) was documented using the first 2.5 yr (2002–05) of version 4 atmospheric specific humidity and temperature profiles from the Atmospheric Infrared Sounder (AIRS). In this study, this issue is further examined using currently available 7-yr version 5 AIRS data (2002–09) to test its dependence on the AIRS data record lengths, AIRS retrieval versions, and MJO event selection and compositing methods employed. The results indicate a strong consistency of the large-scale vertical moist thermodynamic structure of the MJO between different AIRS data record lengths (2.5 vs 7 yr), different AIRS retrieval versions (4 vs 5), and different MJO analysis methods [the extended empirical orthogonal function (EEOF) method vs the multivariate empirical orthogonal function (MEOF) method].
The large-scale vertical moist thermodynamic structures of the MJO between the AIRS retrievals and the ECMWF Interim Re-Analysis (ERA-Interim) products are also compared. The results indicate a much better agreement of the MJO vertical structure between AIRS and ERA-Interim than with the NCEP–NCAR reanalysis, although a significant difference exists in the magnitude of moisture anomalies between ERA-Interim and AIRS. This characterization of the vertical moist thermodynamic structure of the MJO by AIRS and ERA-Interim offers a useful observation-based metric for general circulation model diagnostics.
A Comparison of the Effect of Central Anatomical Single-Bundle Anterior Cruciate Ligament Reconstruction and Double-Bundle Anterior Cruciate Ligament Reconstruction on Pivot-Shift Kinematics
Authors: Bedi Asheesh , Musahl Volker , O’Loughlin Padhraig , Maak Travis , Citak Musa , Dixon Peter , Pearle Andrew D. 
Published: June 2010

Background: Biomechanical differences between anatomical double-bundle and central single-bundle anterior cruciate ligament reconstruction using the same graft tissue have not been defined. Purpose: The purpose of this study was to compare these reconstructions in their ability to restore native knee kinematics during a reproducible Lachman and pivot-shift examination. Study Design: Controlled laboratory study. Methods: Using a computer-assisted navigation system, 10 paired knees were subjected to biomechanical testing with a standardized Lachman and mechanized pivot-shift examination. The navigation system recorded the 3D motion path of a tracked point at the center of the tibia, center of the medial tibial plateau, and center of the lateral tibial plateau with each maneuver. The testing protocol consisted of evaluation in the intact state, after complete anterior cruciate ligament transection, after medial and lateral meniscectomy, and after anterior cruciate ligament reconstruction with (1) a single-bundle center-center or (2) anatomical double-bundle technique. Repeated-measures analysis of variance with a post hoc Tukey test was used to compare the measured translations with each test condition. Results: A significant difference in anterior translation was seen with Lachman examination between the anterior cruciate ligament– and medial and lateral meniscus–deficient condition compared with both the double-bundle and single-bundle center-center anterior cruciate ligament reconstruction ( P < .001); no significant difference was observed between reconstructions. The double-bundle construct was significantly better in limiting anterior translation of the lateral compartment compared with the single-bundle reconstruction during a pivot-shift maneuver (2.0 ± 5.7 mm vs 7.8 ± 1.8 mm, P < .001) and was not significantly different than the intact anterior cruciate ligament condition (2.7 mm ± 4.7 mm, P > .05). Discussion: Although double-bundle and single-bundle, center-center anterior cruciate ligament reconstructions appear equally effective in controlling anterior translation during a Lachman examination, analysis of pivot-shift kinematics reveals significant differences between these surgical reconstructions. An altered rotational axis resulted in significantly greater translation of the lateral compartment in the single-bundle compared with double-bundle reconstruction. Clinical Relevance: A double-bundle anterior cruciate ligament reconstruction may be a favorable construct for restoration of knee kinematics in the at-risk knee with associated meniscal injuries and/or significant pivot shift on preoperative examination.