bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of interactive video test performance to overall class performance in a biomechanics course
Authors: Bennett Guinevere S. 
Published: December 2017

Objective:
This study compared interactive video test performance and students' overall class performance. The hypothesis was that there would be a difference in video test performance compared to overall class performance.

Methods:
A total of 30 students participated in the pilot study from a master's level biomechanics course. Students completed four interactive video tests using EduCanon; content of videos included base of support, lever systems, scapulohumeral rhythm, and postural analysis. This content was reviewed with class discussion after completion of the interactive video test. The tests administered counted toward the participation portion of the final student grade. Student performance on the EduCanon interactive video test was compared to overall class grade using a paired t-test.

Results:
All 30 students completed the 4 EduCanon interactive video tests. Final class grades were greater compared to cumulative EduCanon test performance. There was no difference between performance using interactive video testing compared to students' overall class performance (t[29] = −1.43, p = .16).

Conclusion:
The results of this study did not support improved student assessment performance with incorporation of interactive video testing in the classroom environment. Continued research into new testing strategies is recommended to identify additional effective testing in the classroom.
Training chiropractic students in weight management counseling using standardized patients
Authors: Hawk Cheryl , Ramcharan Michael , Kruger Carla LeRiche 
Published: December 2017

Objective:
The aim of this study was to describe and assess an activity that trained chiropractic students to counsel patients on weight management through the use of standardized patients.

Methods:
This was a descriptive study using mixed methods. Students were trained to apply health behavior theory and the transtheoretical model. Standardized patients were given a case to portray with the students. Students had 15 minutes for the encounter. The encounters were assessed in 2 ways: (1) standardized patients answered a brief questionnaire about the students' performance, and (2) students answered a questionnaire about the utility of the intervention. Numerical data were extracted from the audiovisual management platform, and statistics were computed for each question. Comments made by students and patients were transferred verbatim for content analysis.

Results:
A total of 102 students took part in the activity. Students' performance in the encounter was uniformly high, with over 90% “yes” responses to all questions except “gave me printed information material” and “discussed the printed material with me.” The key issue identified in the comments by standardized patients was that students tended not to connect weight management with their chief complaint (low back pain). Nearly all students (97%) thought the activity would be useful to their future practice, and 97% felt it had increased their confidence in providing weight management counseling.

Conclusion:
This experiential activity was assessed to be useful to students' future practice and appeared to provide them with skills to successfully communicate with patients on weight management.
Seasonal Variability in Regional Ice Flow Due to Meltwater Injection Into the Shear Margins of Jakobshavn Isbræ
Authors: Cavanagh J. P. , Lampkin D. J. , Moon T. 
Published: December 2017

AbstractThe impact of meltwater injection into the shear margins of Jakobshavn Isbræ via drainage from water‐filled crevasses on ice flow is examined. We use Landsat‐8 Operational Land Imager panchromatic, high‐resolution imagery to monitor the spatiotemporal variability of seven water‐filled crevasse ponds during the summers of 2013 to 2015. The timing of drainage from water‐filled crevasses coincides with an increase of 2 to 20% in measured ice velocity beyond Jakobshavn Isbræ shear margins, which we define as extramarginal ice velocity. Some water‐filled crevasse groups demonstrate multiple drainage events within a single melt season. Numerical simulations show that hydrologic shear weakening due to water‐filled crevasse drainage can accelerate extramarginal flow by as much as ~35% within 10 km of the margins and enhance mass flux through the shear margins by 12%. This work demonstrates a novel mechanism through which surface melt can influence regional ice flow.
Seasonal Dependence of Geomagnetic Active‐Time Northern High‐Latitude Upper Thermospheric Winds
Authors: Dhadly Manbharat S. , Emmert John T. , Drob Douglas P. , Conde Mark G. , Doornbos Eelco , Shepherd Gordon G. , Makela Jonathan J. , Wu Qian , Nieciejewski Richard J. , Ridley Aaron J. 
Published: December 2017

AbstractThis study is focused on improving the poorly understood seasonal dependence of northern high‐latitude F region thermospheric winds under active geomagnetic conditions. The gaps in our understanding of the dynamic high‐latitude thermosphere are largely due to the sparseness of thermospheric wind measurements. With current observational facilities, it is infeasible to construct a synoptic picture of thermospheric winds, but enough data with wide spatial and temporal coverage have accumulated to construct a meaningful statistical analysis. We use long‐term data from eight ground‐based and two space‐based instruments to derive climatological wind patterns as a function of magnetic local time, magnetic latitude, and season. These diverse data sets possess different geometries and different spatial and solar activity coverage. The major challenge is to combine these disparate data sets into a coherent picture while overcoming the sampling limitations and biases among them. In our previous study (focused on quiet time winds), we found bias in the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) cross‐track winds. Here we empirically quantify the GOCE bias and use it as a correction profile for removing apparent bias before empirical wind formulation. The assimilated wind patterns exhibit all major characteristics of high‐latitude neutral circulation. The latitudinal extent of duskside circulation expands almost 10∘ from winter to summer. The dawnside circulation subsides from winter to summer. Disturbance winds derived from geomagnetic active and quiet winds show strong seasonal and latitudinal variability. Comparisons between wind patterns derived here and Disturbance Wind Model (DWM07) (which have no seasonal dependence) suggest that DWM07 is skewed toward summertime conditions.
Kilometric Scale Modeling of the North West European Shelf Seas: Exploring the Spatial and Temporal Variability of Internal Tides
Authors: Guihou K. , Polton J. , Harle J. , Wakelin S. , O'Dea E. , Holt J. 
Published: December 2017

AbstractThe North West European Shelf break acts as a barrier to the transport and exchange between the open ocean and the shelf seas. The strong spatial variability of these exchange processes is hard to fully explore using observations, and simulations generally are too coarse to simulate the fine‐scale processes over the whole region. In this context, under the FASTNEt program, a new NEMO configuration of the North West European Shelf and Atlantic Margin at 1/60° (∼1.8 km) has been developed, with the objective to better understand and quantify the seasonal and interannual variability of shelf break processes. The capability of this configuration to reproduce the seasonal cycle in SST, the barotropic tide, and fine‐resolution temperature profiles is assessed against a basin‐scale (1/12°, ∼9 km) configuration and a standard regional configuration (7 km resolution). The seasonal cycle is well reproduced in all configurations though the fine‐resolution allows the simulation of smaller scale processes. Time series of temperature at various locations on the shelf show the presence of internal waves with a strong spatiotemporal variability. Spectral analysis of the internal waves reveals peaks at the diurnal, semidiurnal, inertial, and quarter‐diurnal bands, which are only realistically reproduced in the new configuration. Tidally induced pycnocline variability is diagnosed in the model and shown to vary with the spring neap cycle with mean displacement amplitudes in excess of 2 m for 30% of the stratified domain. With sufficiently fine resolution, internal tides are shown to be generated at numerous bathymetric features resulting in a complex pycnocline displacement superposition pattern.
The Effect of Barotropic and Baroclinic Tides on Coastal Stratification and Mixing
Authors: Suanda S. H. , Feddersen F. , Kumar N. 
Published: December 2017

AbstractThe effects of barotropic and baroclinic tides on subtidal stratification and vertical mixing are examined with high‐resolution, three‐dimensional numerical simulations of the Central Californian coastal upwelling region. A base simulation with realistic atmospheric and regional‐scale boundary forcing but no tides (NT) is compared to two simulations with the addition of predominantly barotropic local tides (LT) and with combined barotropic and remotely generated, baroclinic tides (WT) with
100
onshore baroclinic energy flux. During a 10 day period of coastal upwelling when the domain volume‐averaged temperature is similar in all three simulations, LT has little difference in subtidal temperature and stratification compared to NT. In contrast, the addition of remote baroclinic tides (WT) reduces the subtidal continental shelf stratification up to 50% relative to NT. Idealized simulations to isolate barotropic and baroclinic effects demonstrate that within a parameter space of typical U.S. West Coast continental shelf slopes, barotropic tidal currents, incident energy flux, and subtidal stratification, the dissipating baroclinic tide destroys stratification an order of magnitude faster than barotropic tides. In WT, the modeled vertical temperature diffusivity at the top (base) of the bottom (surface) boundary layer is increased up to 20 times relative to NT. Therefore, the width of the inner‐shelf (region of surface and bottom boundary layer overlap) is increased approximately 4 times relative to NT. The change in stratification due to dissipating baroclinic tides is comparable to the magnitude of the observed seasonal cycle of stratification.
Is the State of the Air‐Sea Interface a Factor in Rapid Intensification and Rapid Decline of Tropical Cyclones?
Authors: Soloviev Alexander V. , Lukas Roger , Donelan Mark A. , Haus Brian K. , Ginis Isaac 
Published: December 2017

AbstractTropical storm intensity prediction remains a challenge in tropical meteorology. Some tropical storms undergo dramatic rapid intensification and rapid decline. Hurricane researchers have considered particular ambient environmental conditions including the ocean thermal and salinity structure and internal vortex dynamics (e.g., eyewall replacement cycle, hot towers) as factors creating favorable conditions for rapid intensification. At this point, however, it is not exactly known to what extent the state of the sea surface controls tropical cyclone dynamics. Theoretical considerations, laboratory experiments, and numerical simulations suggest that the air‐sea interface under tropical cyclones is subject to the Kelvin‐Helmholtz type instability. Ejection of large quantities of spray particles due to this instability can produce a two‐phase environment, which can attenuate gravity‐capillary waves and alter the air‐sea coupling. The unified parameterization of waveform and two‐phase drag based on the physics of the air‐sea interface shows the increase of the aerodynamic drag coefficientwith wind speed up to hurricane force (m s−1). Remarkably, there is a localminimum—“an aerodynamic drag well”—at aroundm s−1. The negative slope of thedependence on wind‐speed between approximately 35 and 60 m s−1favors rapid storm intensification. In contrast, the positive slope ofwind‐speed dependence above 60 m s−1is favorable for a rapid storm decline of the most powerful storms. In fact, the storms that intensify to Category 5 usually rapidly weaken afterward.
Determination of the Global‐Average Charge Moment of a Lightning Flash Using Schumann Resonances and the LIS/OTD Lightning Data
Authors: Boldi Robert , Williams Earle , Guha Anirban 
Published: December 2017

AbstractIn this paper, we use (1) the 20 year record of Schumann resonance (SR) signals measured at West Greenwich Rhode Island, USA, (2) the 19 year Lightning Imaging Sensor (LIS)/Optical Transient Detector (OTD) lightning data, and (3) the normal mode equations for a uniform cavity model to quantify the relationship between the observed Schumann resonance modal intensity and the global‐average vertical charge moment change M (C km) per lightning flash. This work, by integrating SR measurements with satellite‐based optical measurements of global flash rate, accomplishes this quantification for the first time. To do this, we first fit the intensity spectra of the observed SR signals to an eight‐mode, three parameter per mode, (symmetric) Lorentzian line shape model. Next, using the LIS/OTD lightning data and the normal mode equations for a uniform cavity model, we computed the expected climatological‐daily‐average intensity spectra. We then regressed the observed modal intensity values against the expected modal intensity values to find the best fit value of the global‐average vertical charge moment change of a lightning flash (M) to be 41 C km per flash with a 99% confidence interval of ±3.9 C km per flash, independent of mode. Mode independence argues that the model adequately captured the modal intensity, the most important fit parameter herein considered. We also tested this relationship for the presence of residual modal intensity at zero lightning flashes per second and found no evidence that modal intensity is significantly different than zero at zero lightning flashes per second, setting an upper limit to the amount of nonlightning contributions to the observed modal intensity.
Spectral Characteristics of VLF Sferics Associated With RHESSI TGFs
Authors: Mezentsev Andrew , Lehtinen Nikolai , Østgaard Nikolai , Pérez‐Invernón F. J. , Cummer Steven A. 
Published: December 2017

AbstractWe compared the modeled energy spectral density of very low frequency (VLF) radio emissions from terrestrial gamma ray flashes (TGFs) with the energy spectral density of VLF radio sferics recorded by Duke VLF receiver simultaneously with those TGFs. In total, six events with world wide lightning location network (WWLLN) defined locations were analyzed to exhibit a good fit between the modeled and observed energy spectral densities. In VLF range the energy spectral density of the TGF source current moment is found to be dominated by the contribution of secondary low‐energy electrons and independent of the relativistic electrons which play their role in low‐frequency (LF) range. Additional spectral modulation by the multiplicity of TGF peaks was found and demonstrated a good fit for two TGFs whose VLF sferics consist of two overlapping pulses each. The number of seeding pulses in TGF defines the spectral shape in VLF range, which allows to retrieve this number from VLF sferics, assuming they were radiated by TGFs. For two events it was found that the number of seeding pulses is small, of the order of 10. For the rest of the events the lower boundary of the number of seeding pulses was found to be between 10 to 103.
Constraints on Meteoric Smoke Composition and Meteoric Influx Using SOFIE Observations With Models
Authors: Hervig Mark E. , Brooke James S. A. , Feng Wuhu , Bardeen Charles G. , Plane John M. C. 
Published: December 2017

AbstractThe composition of meteoric smoke particles in the mesosphere is constrained using measurements from the Solar Occultation For Ice Experiment (SOFIE) in conjunction with models. Comparing the multiwavelength observations with models suggests smoke compositions of magnetite, wüstite, magnesiowüstite, or iron‐rich olivine. Smoke compositions of pure pyroxene, hematite, iron‐poor olivine, magnesium silicate, and silica are excluded, although this may be because these materials have weak signatures at the SOFIE wavelengths. Information concerning smoke composition allows the SOFIE extinction measurements to be converted to smoke volume density. Comparing the observed volume density with model results for varying meteoric influx (MI) provides constraints on the ablated fraction of incoming meteoric material. The results indicate a global ablated MI of 3.3 ± 1.9 t d−1, which represents only iron, magnesium, and possibly silica, given the smoke compositions indicated here. Considering the optics and iron content of individual smoke compositions gives an ablated Fe influx of 1.8 ± 0.9 t d−1. Finally, the global total meteoric influx (ablated plus surviving) is estimated to be 30 ± 18 t d−1, when considering the present results and a recent description of the speciation of meteoric material.
Unraveling the Role of Temperature and Rainfall on Active Fires in the Brazilian Amazon Using a Nonlinear Poisson Model
Authors: Lima Carlos H. R. , AghaKouchak Amir , Randerson James T. 
Published: December 2017

AbstractExtreme droughts and high temperatures have become more frequent in the last two decades, increasing fire risk in the Amazon. The overarching goal of this study is to shed light on the influence of temperature and rainfall on fire occurrence for the 1998–2013 period. We use a Poisson regression to model satellite‐based monthly fire counts across the Brazilian Amazon as a function of observed rainfall and temperature. Specifically, in the nonlinear regression framework we explore the fire count at month t as a function of the total monthly rainfall and monthly average of maximum daily temperatures at month t as well as lagged observations of these two predictors and of the fire counts. Our results indicate that the influence of temperature on fire counts can be larger than the effects of rainfall. Considering the temperature‐fire relationship, the extra variance explained by rainfall is about 9%. Assuming average rainfall, we show that a 1°C increase in the monthly average of maximum daily temperatures results in a 30% increase in fire counts (19 fires per Mha more than the average), which translates into significant changes in the likelihood of fires within the Amazon. Our findings provide new insight about the role of temperature and rainfall in regulating fire occurrence in the Amazon, and the sensitivity of fire counts to relatively small changes in temperature highlights the vulnerability of the Amazon in a warming climate, where much higher temperatures are expected by the end of this century.
Anthropogenic Phosphorus Inputs to a River Basin and Their Impacts on Phosphorus Fluxes Along Its Upstream‐Downstream Continuum
Authors: Zhang Wangshou , Swaney Dennis P. , Hong Bongghi , Howarth Robert W. 
Published: December 2017

AbstractThe increasing trend in riverine phosphorus (P) loads resulting from anthropogenic inputs has gained wide attention because of the well‐known role of P in eutrophication. So far, however, there is still limited scientific understanding of anthropogenic P inputs and their impacts on riverine flux in river reaches along the upstream‐to‐downstream continuum. Here we investigated P budgets in a series of nested watersheds draining into Hongze Lake of China and developed an empirical function to describe the relationship between anthropogenic inputs and riverine P fluxes. Our results indicated that there are obvious gradients regarding P budgets in response to changes in human activities. Fertilizer application and food and feed P import was always the dominant source of P inputs in all sections, followed by nonfood P. Further interpretation using the model revealed the processes of P loading to the lake. About 2%–9% of anthropogenic P inputs are transported from the various sections into the corresponding tributaries of the river systems, depending upon local precipitation rates. Of this amount, around 41%–95% is delivered to the main stem of the Huai River after in‐stream attenuation in its tributaries. Ultimately, 55%–86% of the P loads delivered to different locations of the main stem are transported into the receiving lake of the downstream, due to additional losses in the main stem. An integrated P management strategy that considers the gradients of P loss along the upstream‐to‐downstream continuum is required to assess and optimize P management to protect the region's freshwater resource.
Empirical Modeling of the Quiet and Storm Time Geosynchronous Magnetic Field
Authors: Andreeva V. A. , Tsyganenko N. A. 
Published: December 2017

AbstractA dynamical empirical model of the near‐geosynchronous magnetic field has been constructed, based on a recently developed radial basis functions approach and a multiyear set of spacecraft data taken by Time History of Events and Macroscale Interactions during Substorms (THEMIS), Polar, Cluster, and Van Allen Probes missions including 133 geomagnetic storms in the time interval between 1996 and 2016. The model describes the field as a function of Cartesian solar magnetic coordinates, dipole tilt angle, and solar wind ram pressure and of a set of dynamic variables representing the response of the magnetosphere to the external driving/loading during the active phase of a space weather event, followed by the internal relaxation/dissipation during the storm recovery. In terms of the disturbance level, the model's validity range extends to intense storms with peakSYM‐Hvalues down to −150 nT. The spatial validity domain is a toroidal volume bounded by the inner (L∼ 5) and outer (L∼ 9) dipolar L shells, which allows the model to be used for tracing field lines to magnetically map geosynchronous spacecraft locations down to low altitudes. The model has been validated on independent out‐of‐sample magnetic field data and compared with an earlier empirical model and GOES 15 data taken in 2012 and 2015.