bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution of Hand Motor Circuits to Counting
Authors: Andres Michael , Seron Xavier , Olivier Etienne 
Published: March 2007

Abstract
The finding that number processing activates a cortical network partly overlapping that recruited for hand movements has renewed interest in the relationship between number and finger representations. Further evidence about a possible link between fingers and numbers comes from developmental studies showing that finger movements play a crucial role in learning counting. However, increased activity in hand motor circuits during counting may unveil unspecific processes, such as shifting attention, reciting number names, or matching items with a number name. To address this issue, we used transcranial magnetic stimulation to measure changes in corticospinal (CS) excitability during a counting task performed silently and using either numbers or letters of the alphabet to enumerate items. We found an increased CS excitability of hand muscles during the counting task, irrespective of the use of numbers or letters, whereas it was unchanged in arm and foot muscles. Control tasks allowed us to rule out a possible influence of attention allocation or covert speech on CS excitability increase of hand muscles during counting. The present results support a specific involvement of hand motor circuits in counting because no CS changes were found in arm and foot muscles during the same task. However, the contribution of hand motor areas is not exclusively related to number processing because an increase in CS excitability was also found when letters were used to enumerate items. This finding suggests that hand motor circuits are involved whenever items have to be put in correspondence with the elements of any ordered series.
fMRI Data Predict Individual Differences of Behavioral Effects of Nicotine: A Partial Least Square Analysis
Authors: Giessing C. , Fink G. R. , Rösler F. , Thiel C. M. 
Published: March 2007

Abstract
Reorienting of visuospatial attention can be investigated by comparing reaction times to validly and invalidly cued targets (“validity effect”). The cholinergic agonist nicotine reduces the validity effect and neural activity in the posterior parietal cortex. Behavioral effects of nicotine in nonsmokers are weak and it has been suggested that differences in baseline behavior before nicotine exposure may influence the effect of nicotine. This study investigates whether individual differences in reorienting-related neural activity under placebo may be used to predict individual nicotine effects. Individual nicotine effects are defined as the behavioral effects under nicotine that cannot be predicted by the behavioral data under placebo. Fifteen nonsmoking subjects were given either placebo or nicotine gum (2 mg) prior to performing a cued target detection task inside a magnetic resonance imaging scanner. The results of a partial least square analysis suggest that neural data under placebo can be used to predict individual behavioral effects of nicotine. Neural activity in the left posterior cingulate cortex, the right superior parietal cortex, the right dorsal medial prefrontal cortex, and the left ventral medial prefrontal cortex significantly contributes to that prediction. We conclude that nicotine effects on reorienting attention depend on individual differences in reorienting-related neural activity under placebo and suggest that functional magnetic resonance imaging data can contribute to the prediction of individual drug effects.
Ground-Based Solar Absorption FTIR Spectroscopy: Characterization of Retrievals and First Results from a Novel Optical Design Instrument at a New NDACC Complementary Station
Authors: Wiacek A. , Taylor J. R. , Strong K. , Saari R. , Kerzenmacher T. E. , Jones N. B. , Griffith D. W. T. 
Published: March 2007

Abstract
The authors describe the optical design of a high-resolution Fourier Transform Spectrometer (FTS), which serves as the primary instrument at the University of Toronto Atmospheric Observatory (TAO). The FTS is dedicated to ground-based infrared solar absorption atmospheric measurements from Toronto, Ontario, Canada. Instrument performance is discussed in terms of instrumental line shape (ILS) and phase error and modulation efficiency as a function of optical path difference. Typical measurement parameters are presented together with retrieval parameters used to derive total and partial column concentrations of ozone. Retrievals at TAO employ the optimal estimation method (OEM), and some impacts of the necessary a priori constraints are examined. In March 2004, after participating in a retrieval algorithm user intercomparison exercise, the TAO FTS was granted the status of a Complementary Observation Station within the international community of high-resolution FTS users in the Network for the Detection of Atmospheric Composition and Change (NDACC). During this exercise, average differences between total columns retrieved from the same spectra by different users were below 2.1% for O3, HCl, and N2O in the blind phase, and below 1% in the open phase, when all retrieval constraints were identical. Finally, a 2.5-yr time series of monthly mean stratospheric ozone columns agrees within 3% with those retrieved from Optical Spectrograph and Infrared Imager System (OSIRIS) measurements on board the Odin satellite, which is within the errors of both measurement platforms.
Statewide Monitoring of the Mesoscale Environment: A Technical Update on the Oklahoma Mesonet
Authors: McPherson Renee A. , Fiebrich Christopher A. , Crawford Kenneth C. , Kilby James R. , Grimsley David L. , Martinez Janet E. , Basara Jeffrey B. , Illston Bradley G. , Morris Dale A. , Kloesel Kevin A. , Melvin Andrea D. , Shrivastava Himanshu , Wolfinbarger J. Michael , Bostic Jared P. , Demko David B. , Elliott Ronald L. , Stadler Stephen J. , Carlson J. D. , Sutherland Albert J. 
Published: March 2007

Abstract
Established as a multipurpose network, the Oklahoma Mesonet operates more than 110 surface observing stations that send data every 5 min to an operations center for data quality assurance, product generation, and dissemination. Quality-assured data are available within 5 min of the observation time. Since 1994, the Oklahoma Mesonet has collected 3.5 billion weather and soil observations and produced millions of decision-making products for its customers.
A CCD Spectroradiometer for Ultraviolet Actinic Radiation Measurements
Authors: Jäkel Evelyn , Wendisch Manfred , Blumthaler Mario , Schmitt Rainer , Webb Ann R. 
Published: March 2007

Abstract
A new spectroradiometer for spectral measurements of ultraviolet (UV) atmospheric radiation (290–400 nm) using a charge coupled device (CCD) as a detector is introduced. The instrument development is motivated by the need for measurements with (a) high accuracy in the UV-B spectral range (290–315 nm) for photochemistry applications and (b) high temporal resolution in quickly changing atmospheric conditions such as partial cloud cover. The new CCD instrument is mainly intended for airborne use. It allows fast data collection (&lt;300 ms time resolution for each spectrum) with improved sensitivity in the UV spectral range. The instrumental setup and its characterization in terms of stray light, dark current, noise, and detection limits are described and compared to a spectroradiometer with a photodiode array (PDA) detector. The new CCD spectroradiometer has a one order of magnitude greater sensitivity than the PDA-based spectroradiometer. However, the stray light of the CCD instrument is wavelength dependent, which requires a more complicated data evaluation procedure than the PDA instrument. Comparison with other UV spectroradiometers (a PDA spectroradiometer and two ground-based double monochromators) shows the advantages of the CCD system for UV-B measurements of actinic flux densities and photolysis frequencies of ozone and nitrogen dioxide, and the improved performance compared to PDA spectroradiometers.
Reconstruction of the Sizes of Spherical Particles from Their Shadow Images. Part I: Theoretical Considerations
Authors: Korolev Alexei 
Published: March 2007

Abstract
Imaging optical array probes (OAPs) have become conventional instruments in studies of cloud microphysics. Previous works have shown that the error particle sizing in OAPs may reach 100%. Correcting the particle size measurements is not a trivial task, since the error depends on its size and distance from the object plane. A new technique for the size reconstruction of spherical particles from its measured image is introduced here. This technique also enables the retrieval of the particle position along the depth of field in the sample volume. The essence of the algorithm consists in the deduction of size and position from the relationships between the size of the Poisson spots and the geometrical dimensions of the image. The retrieval technique has been tested on the simulated discrete binary diffraction images of spherical particles, similar to those produced by OAPs. The images were modeled using the Fresnel diffraction approximation. It is demonstrated that the new algorithm can be applied to discrete binary images of spherical particles consisting of more than three pixels in size. An important feature of the retrieval technique is that it does not depend on the pixel resolution, and it can be applied for any type of OAPs that use a monochromatic coherent source of illumination.
Analysis of Radiosonde and Ground-Based Remotely Sensed PWV Data from the 2004 North Slope of Alaska Arctic Winter Radiometric Experiment
Authors: Mattioli V. , Westwater E. R. , Cimini D. , Liljegren J. C. , Lesht B. M. , Gutman S. I. , Schmidlin F. J. 
Published: March 2007

Abstract
During 9 March–9 April 2004, the North Slope of Alaska Arctic Winter Radiometric Experiment was conducted at the Atmospheric Radiation Measurement Program’s (ARM) “Great White” field site near Barrow, Alaska. The major goals of the experiment were to compare microwave and millimeter wavelength radiometers and to develop forward models in radiative transfer, all with a focus on cold (temperature from 0° to −40°C) and dry [precipitable water vapor (PWV) &lt; 0.5 cm] conditions. To supplement the remote sensors, several radiosonde packages were deployed: Vaisala RS90 launched at the ARM Duplex and at the Great White and Sippican VIZ-B2 operated by the NWS. In addition, eight dual-radiosonde launches were conducted at the Duplex with Vaisala RS90 and Sippican GPS Mark II, the latter one modified to include a chilled mirror humidity sensor. Temperature comparisons showed a nighttime bias between VIZ-B2 and RS90, which reached 3.5°C at 30 hPa. Relative humidity comparisons indicated better than 5% average agreement between the RS90 and the chilled mirror. A bias of about 20% for the upper troposphere was found in the VIZ-B2 and the Mark II measurements relative to both RS90 and the chilled mirror.
Comparisons in PWV were made between a microwave radiometer, a microwave profiler, a global positioning system receiver, and the radiosonde types. An RMS agreement of 0.033 cm was found between the radiometer and the profiler and better than 0.058 cm between the radiometers and GPS. RS90 showed a daytime dry bias on PWV of about 0.02 cm.
Variational Analysis of Oversampled Dual-Doppler Radial Velocity Data and Application to the Analysis of Tornado Circulations
Authors: Xue Ming , Liu Shun , Yu Tian-You 
Published: March 2007

Abstract
For the detection of severe weather phenomena such as tornados, mesocyclones, and strong wind shear, the azimuthal resolution of radial velocity measurements is more important. The typical azimuthal resolutions of 1° for the Weather Surveillance Radar-1988 Doppler (WSR-88D) radars and of 2° for the planned Center for Collaborative Adaptive Sensing of Atmosphere (CASA) radars are not sufficient for this purpose, especially at far ranges. Oversampling is one strategy that can potentially provide more details about the azimuthal structures of flows, and can be achieved by processing raw data at azimuthal increments smaller than the radar beamwidth. In the presence of dual-Doppler observations, the variational method can be used to effectively recover subbeamwidth structures from these oversampled data, which, combined with the typically higher range resolutions, can provide high-resolution wind analyses that are valuable for, for example, tornado detection. This idea is tested in this paper using simulated data as well as reprocessed level-I data from a research WSR-88D radar, for model-simulated and actually observed tornadoes, respectively. The results confirm that much more detailed, often subbeamwidth, flow structures can indeed be recovered through azimuthal oversampling and a properly configured variational analysis, and the detailed flow analysis is expected to significantly improve one’s ability in identifying small-scale features such as tornadoes from radial velocity observations.
Using Wavelet Analysis to Detect Tornadoes from Doppler Radar Radial-Velocity Observations
Authors: Liu Shun , Xue Ming , Xu Qin 
Published: March 2007

AbstractA wavelet-based algorithm is developed to detect tornadoes from Doppler weather radar radial-velocity observations. Within this algorithm, a relative region-to-region velocity difference (RRVD) is defined based on the scale- and location-dependent wavelet coefficients and this difference represents the relative magnitude of the radial velocity shear between two adjacent regions of different scales. The RRVD fields of an idealized tornado and a realistic tornado from a high-resolution numerical simulation are analyzed first. It is found that the value of RRVD in the tornado region is significantly larger than those at other locations and large values of RRVD exist at more than one scale. This characteristic forms the basis of the new algorithm presented in this work for identifying tornadoes. Different from traditional tornadic vortex signature detection algorithms that typically rely on the velocity difference between adjacent velocity gate pairs at a single spatial scale, the new algorithm examines region-to-region radial wind shears at a number of different spatial scales. Multiscale regional wind shear examination not only can be used to discard a nontornadic vortex signature to reduce the false alert rate of tornado detection but also has the ability of capturing tornadic signatures at various scales for improving the detection and warning. The potential advantage of the current algorithm is demonstrated by applying it to the radar data collected by Oklahoma City, Oklahoma (KTLX), Weather Surveillance Radar-1988 Doppler (WSR-88D) on 8 May 2003 for a central Oklahoma tornado case.
The Effect of Filter Dimension on the Subgrid-Scale Stress, Heat Flux, and Tensor Alignments in the Atmospheric Surface Layer
Authors: Higgins Chad W. , Meneveau Charles , Parlange Marc B. 
Published: March 2007

Abstract
In field experiments designed to study subgrid-scale parameterizations for large eddy simulation, the flow field is often measured and then filtered in two-dimensional planes. This two-dimensional filtering serves as a surrogate for three-dimensional filtering. The question of whether this will yield accurate results in subgrid-scale (SGS) models is addressed by analyzing data from a field experiment in which 16 sonic anemometers were deployed in a four by four grid. The experiment was held in July 2002 at the Surface Layer Turbulence and Environmental Science Test (SLTEST) facility in the Utah West Desert. The full SGS stress tensor and its parameterizations using both two- and three-dimensional filterings are obtained. Comparisons are given between two- and three-dimensional filterings of the field measurements based on probability density functions (PDFs) and energy spectra of the SGS stress elements. The PDFs reveal that quantities calculated with two-dimensional filtering exhibit greater intermittency than those computed with three-dimensional filtering at the same scale. From the spectra it is observed that the different filtering methods result in similar behavior, but that spectra of SGS stress components computed with a three-dimensional filter roll off at a slightly lower wavenumber than those computed with a two-dimensional filter. The PDFs and spectra of the stresses calculated with two- and three-dimensional filters can be made to collapse by reducing the three-dimensional filter scale according to Δ3−D = 0.84Δ2−D. Geometric alignment analyses are performed for the SGS heat flux, SGS stress, and filtered strain rate for the cases of stable, near-neutral, and unstable atmospheric stabilities. Under unstable and near-neutral atmospheric stability, two-dimensional filtering yields acceptable results; however, under stable atmospheric stability, a new approach is recommended and delineated.
Structural Integrity and Clinical Function of the Subscapularis Musculotendinous Unit after Arthroscopic and Open Shoulder Stabilization
Authors: Scheibel Markus , Nikulka Constanze , Dick Anton , Schroeder Ralf Juergen , Popp Ariane Gerber , Haas Norbert P. 
Published: March 2007

Background Postoperative subscapularis dysfunction after open shoulder stabilization has recently received increasing attention. The potential advantage of arthroscopic stabilization procedures is that they do not violate the subscapularis musculotendinous unit, which might preserve its structural integrity and clinical function, which would lead to superior clinical results. Hypothesis Arthroscopic shoulder stabilization does not lead to clinical and radiological signs of subscapularis insufficiency. Study Design Cohort study; Level of evidence, 3. Methods Twenty-two patients who underwent arthroscopic (group I, n = 12; average age, 30.9 years; mean follow-up, 37 months) or open (group II, n = 10; average age, 28.8 years; mean follow-up, 35.9 months) shoulder stabilization procedure were followed up clinically (clinical subscapularis tests and signs, Constant Score, Rowe Score, Walch-Duplay Score, Western Ontario Shoulder Instability Index and Melbourne Instability Shoulder Score) and by magnetic resonance imaging (subscapularis tendon integrity, cross-sectional area, defined muscle diameters, and signal intensity analysis [ratio infraspinatus/upper subscapularis and infraspinatus/lower subscapularis]). A third group (group 0) of 12 healthy volunteers served as a control. Results Clinical signs for subscapularis insufficiency were present in 0% of cases in group I and in 70% of cases in group II. There were no statistically significant differences in either group regarding Constant Score, Rowe Score, Walch-Duplay Score, Western Ontario Shoulder Instability Index, and Melbourne Instability Shoulder Score (P > .05). On magnetic resonance image, no subscapularis tendon ruptures were found. The cross-sectional area, the mean vertical diameter, and the mean transverse diameter of the upper and lower subscapularis muscle portion was significantly less in group II than in group 0 (P < .05). The signal intensity analysis revealed the infraspinatus/upper subscapularis ratio was significantly lower in group II than in group I or group 0. The infraspinatus/lower subscapularis ratio did not significantly differ in all 3 groups (P > .05). Conclusion This study confirms previous observations that open shoulder stabilization using a subscapularis tenotomy may lead to atrophy and fatty infiltration of the subscapularis muscle, resulting in postoperative subscapularis dysfunction. As expected, arthroscopic procedures do not significantly compromise clinical subscapularis function and structural integrity. However, no significant differences were observed in the overall outcome.
Avulsion Fracture of the Lateral Ankle Ligament Complex in Severe Inversion Injury
Authors: Haraguchi Naoki , Toga Hidekazu , Shiba Nobumasa , Kato Fumio 
Published: March 2007

Background Avulsion fracture of the lateral ankle ligaments is often undetected on early radiographs. The epidemiology and treatment of such avulsion fractures have received much less attention than the epidemiology and treatment of rupture of these ligaments. Hypothesis The clinical characteristics of avulsion fracture are different from those of ligament rupture. Unlike nonoperative treatment of lateral ligament rupture, nonoperative treatment of avulsion fracture does not yield satisfactory results. Study Design Cohort study; Level of evidence, 2. Methods A total of 169 consecutive patients with severe inversion injury were classified into a ligament rupture group or avulsion fracture group on the basis of physical examination findings and anterior talofibular ligament and calcaneofibular ligament radiographic views. Age, sex, activity level, and the mechanism of injury were analyzed. Patients in both groups were treated by casting. Follow-up examination of 152 patients included clinical assessment and functional evaluation based on the Karlsson system. Results Avulsion fracture was diagnosed in 44 (26%) of the 169 patients and was most common among children and patients over 40 years of age. Sedentary level activity and low-energy injury were more common in the avulsion fracture group than in the ligament rupture group (77% vs 37%, respectively, P = .001; 68% vs 43%, respectively, P = .004). Nonoperative treatment of avulsion fracture (mean Karlsson score, 89.1 points) yielded satisfactory results that were comparable with those of nonoperative treatment of ligament rupture (mean Karlsson score, 88.4 points) (P = .123). Osseous union was achieved in 65% of the patients with avulsion fracture. Conclusion Avulsion fracture of the lateral ankle ligaments in cases of severe inversion injury is more common than previously believed. Because of the high incidence and difficulty of detection in children, a high level of suspicion is necessary in order to obtain an accurate diagnosis of avulsion fracture in cases of severe inversion injury and to achieve adequate stability.