bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction between phonemic abilities and syllable congruency effect in young readers
Authors: CHETAIL FABIENNE , MATHEY STÉPHANIE
Published: January 2012

This study investigated whether and to what extent phonemic abilities of young readers (Grade 5) influence syllabic effects in reading. More precisely, the syllable congruency effect was tested in the lexical decision task combined with masked priming in eleven-year-old children. Target words were preceded by a pseudo-word prime sharing the first three letters that either corresponded to the syllable (congruent condition) or not (incongruent condition). The data showed that the syllable priming effect interacted with the score of phonemic abilities. In children with good phonemic skills, word recognition was delayed in the congruent condition compared to the incongruent condition, while it was speeded up in children with weaker phonemic skills. These findings are discussed in a lexical access model including syllable units.
Working together online to enhance learner autonomy: Analysis of learners’ perceptions of their online learning experience
Authors: Eneau Jérôme , Develotte Christine
Published: January 2012

This study concerns the development of autonomy in adult learners working on an online learning platform as part of a professional master's degree programme in “French as a Foreign Language”. Our goal was to identify the influence of reflective and collaborative dimensions on the construction of autonomy for online learners in this programme. The material used was 27 self-analysis papers in response to an assignment which asked students to review their distance learning experience (reflective dimension) and to highlight the role of others, if any, in their learning (collaborative dimension). In addition to these two major points, the analysis by category of the body of results shows principally that in qualitative terms, the factors of autonomisation for online learning are interconnected and include: the difficulties related to distance learning and the strategies that learners develop to face those difficulties, the importance of interpersonal relationships in social and emotional terms in overcoming those difficulties, the specific modes of sociability developed for distance learning and the related development of a new type of autonomy that is both individual and collective. The discussion examines the creation, over the course of time, of a new “distance learning culture” that is nonetheless never easy to create and share.
A case study of language learners’ social presence in synchronous CMC
Authors: Ko Chao-Jung
Published: January 2012

This study adopts a case study approach to investigate the impacts of synchronous computer-mediated communication (CMC) learning environments on learners’ perception of social presence. The participants were twelve French as a foreign language (FFL) beginners in a Taiwanese university. Divided into three groups, they conducted some tasks in three different learning environments (video/audio, audio and face-to-face) during an academic semester. Before each oral task, all the participants had to conduct the same task in synchronous text chat. The participants’ interview transcriptions, learning journals and the instructor's observation journal provided information about the impacts of each environment on their perception of social presence. The results of the study suggested that the differences in the environments are reflected in the learners’ perception of social presence.
Effects of required and optional exchange tasks in online language learning environments
Authors: Brandl Klaus
Published: January 2012

This study investigates the effects of an optional and required (jigsaw) task on learners’ quantity and quality of use of language under synchronous and asynchronous conditions. The question raised is: Does performing either of these task types under synchronous conditions cause a compounding effect that either positively or negatively impacts language production? Eighty-six beginning learners of German participated in this study. The results show that the optional task yielded significantly more learner output, both in terms of target language and c-unit counts. The impact of the condition appears to be mixed, favoring the synchronous mode. Regarding quality, students produced fewer errors when performing the required than the optional task. The results of this study have implications for task design and implementation in online learning environments.
Teaching the Presidency: Idealizing a Constitutional Office
Authors: Fisher Louis
Published: January 2012

From World War II to the present, prominent scholars placed their hopes in the presidency to protect the nation from outside threats and deal effectively with domestic crises. Their theories weakened the constitutional system of separation of powers and checks and balances by reviving an outsized trust in executive power (especially over external affairs) that William Blackstone and others promoted in eighteenth-century England. The American framers of the Constitution studied those models with great care and fully rejected those precedents when they declared their independence from England.
Has Political Science Ignored Religion?
Authors: Kettell Steven
Published: January 2012

A common complaint from political scientists involved in the study of religion is that religious issues have been largely overlooked by political science. Through a content analysis of leading political science and sociology journals from 2000 to 2010, this article considers the extent of this claim. The results show that political science publications involving religious topics have been significantly fewer than those engaging with subjects typically regarded as being more central to the discipline, and markedly less numerous than religious articles in leading sociology publications. Where political science publications have engaged with religious issues, these articles have also focused on a limited number of subject areas and been concentrated in specific disciplinary subfields. The proportion of articles covering religion has shown no real increase since the turn of the century. These findings underpin calls for political scientists to take religious issues more seriously.
Career Preparation and the Political Science Major: Evidence from Departments
Authors: Collins Todd A. , Knotts H. Gibbs , Schiff Jen
Published: January 2012

We know little about the amount of career preparation offered to students in political science departments. This lack of information is particularly troubling given the state of the current job market and the growth of applied degree programs on university campuses. To address this issue, this article presents the results of a December 2010 survey of 279 political science department chairs that asked questions about the level of career preparation in their respective departments. Based on our empirical findings, we believe that political science departments are not doing enough to address their students' career preparation. Our results demonstrate that most departments rely on voluntary internships and faculty advisers to address career-related issues for political science majors. Only a few departments use required internships, required resumes, specific classes related to career preparation, and social media sites such as Facebook and LinkedIn to support career preparation. We also found substantial differences in career preparation across department type (BA, MA, and PhD) and between public and private universities, urban and rural universities, and universities with different average SAT scores. Our findings should interest faculty and administrators who are concerned with different approaches to career preparation on college campuses.
Teaching “Islam and Human Rights” in the Classroom
Authors: Muedini Fait A.
Published: January 2012

This article discusses my approach to teaching a course on Islam and human rights. I begin by examining the attention Islam has received in the media and classroom. Then, I discuss how I structure lectures on Islam and human rights, the various readings associated with the lectures, as well as common themes discussed in class that include but are not limited to Islamic law, women's rights, and minority rights. From there, I discuss a range of different approaches to the Islam and human rights discourse. I then describe how I test the students' knowledge of the material.
Adding an Integrated Library Component to an Undergraduate Research Methods Course
Authors: Gilbert Julie K. , Knutson Katherine , Gilbert Christopher P.
Published: January 2012

As undergraduate students increasingly rely on the Internet as their primary method for gathering sources, they often overlook the rich and varied resources available to them in library collections. Furthermore, students often lack the sophistication to effectively seek out and use information, an ability generally referred to as information literacy. Political scientists and librarians at one institution sought to address the gap in student information literacy skills by creating and implementing a semester-long library lab component integrated into the required research methods course within the political science department. This article presents the steps taken to implement the lab component, including the student learning outcomes we sought to address. We also focus on the measures we used to assess the impact of the lab component. Students who participated in the lab component demonstrate markedly improved information literacy skills compared to those who did not.
After Utøya: How a High-Trust Society Reacts to Terror—Trust and Civic Engagement in the Aftermath of July 22
Authors: Wollebæk Dag , Enjolras Bernard , Steen-Johnsen Kari , Ødegård Guro
Published: January 2012

The article examines short-term effects of terror on trust and civic engagement in Norway. Prior to the July 22, 2011 attacks, Norway ranked among the nations with the highest levels of trust and civic engagement in the world. How does a nation of trusters react to terror? Based on two web surveys conducted in March/April 2011 and August 2011 short-term effects on trust, fear, and political interest and participation are analyzed. Two competing hypotheses are explored: first, the “end-of-innocence hypothesis,” which assumes that the attacks have disrupted trust and instilled a new culture of fear, and second, the “remobilization hypothesis,” which assumes that the attacks have led to a reinforcement of trust and of civic values. Our results show increased interpersonal and institutional trust as well as a modest increase in civic engagement, especially among youth. Moreover, there is little increase in experienced fear within the population. Our study therefore supports the remobilization-of-trust hypothesis. Contrary to the intended aims of the attacker, the structures of trust and civic engagement seem to have been reinforced in Norwegian society. This study in part corroborates findings concerning short-term effects after September 11, 2001.
Practicing Politics: Female Political Scientists as Candidates for Elective Office
Authors: Burrell Barbara
Published: January 2012

In 2007, University of Oklahoma political science professor Cindy Simon Rosenthal was elected mayor of Norman, Oklahoma, after having served as a member of its city council. Was her activity unique within the political science profession among female political scientists? Her election stimulated the curiosity of some of us in the women-and-politics-research community. To what extent had female political scientists attempted to move from the “Ivory Tower” to the “Public Square” as elective office holders? What had their experiences been like? We explore those questions with particular interest in a number of theoretical propositions from women and politics studies. For example, how did they decide to seek elective office? Were they self-starters or had they been recruited? What role did their families play in their campaigns? To what extent was gender perceived as a factor, and in what ways in their various campaigns? How successful were they, and what role did their academic credentials play in their campaigns? Did their quests for public office affect their academic careers? Did they use the findings from the women and politics literature to inform their quests? Perhaps, too, we thought, their campaigns might provide distinctive insights about running for and serving in public office and inform discussion about the role of gender in political life.
The Center: A Look at the Centennial Center for Political Science & Public Affairs
Authors: Biggs Jeff
Published: January 2012

You could call it serendipity or a mutually felicitous target of opportunity, but the APSA Congressional Fellowship Program and the Centennial Center for Political Science & Public Affairs—now under my and Veronica Jones' direction—found productive common ground in November 2011 that will continue into the programs' future. In addition to physical proximity—the two programs share the same floor at APSA—the similar content areas and background shared by Centennial Scholars and Congressional Fellows Program has overlapped since the center's founding seven years ago. Centennial Center scholars have been routinely invited to participate in any segment of the fellowship's six-week orientation program that was of interest to them. And, over the years, several of the scholars later became congressional fellows.
Expressing Religiosity in a Secular Society: the Relativisation of Faith in Muslim Communities in Sweden
Authors: Roald Anne Sofie
Published: January 2012

This article discusses religion in public space and the case study is Muslim minorities in Sweden. The discussion deals with secularisation trends within Muslim communities in Swedish society in view of the notion of counter-secularisation as a fixed and unchanged form of religious expressions in contemporary public life. What happens in Muslim communities as Muslims of various cultural backgrounds and religious orientations meet and interact in a new secular context? The article argues that, similar to the nineteenth and twentieth centuries, Christian reform movements opened up for a relativisation of faith and thus to a certain extent initiated a secularisation process, a relativisation of faith is at present an ongoing process in Muslim communities in Sweden. Of the three definitions on secularisation, promoted by Jose Casanova, secularisation as ‘differentiation of the secular spheres from religious institutions and norms’, ‘marginalisation of religion to a privatised sphere’, and ‘the decline of religious belief and practices’, Muslim practices in Sweden indicate an adherence to these two first notions of the relation between ‘church and state’. As for the last definition of secularisation; ‘the decline of religious belief and practices’, which has to do with private religious practices, many Muslims would regard themselves as religious without claiming a public role for religion, similar to many Christians in Sweden. Furthermore, many of the traits considered to be ‘religious’, might well be attempts to protect a particular cultural context rather than being signs on increased religion as such.
Language proficiency, home-language status, and English vocabulary development: A longitudinal follow-up of the Word Generation program
Authors: LAWRENCE JOSHUA F. , CAPOTOSTO LAUREN , BRANUM-MARTIN LEE , WHITE CLAIRE , SNOW CATHERINE E.
Published: January 2012

This longitudinal quasi-experimental study examines the effects of Word Generation, a middle-school vocabulary intervention, on the learning, maintenance, and consolidation of academic vocabulary for students from English-speaking homes, proficient English speakers from language-minority homes, and limited English-proficiency students. Using individual growth modeling, we found that students receiving Word Generation improved more on target word knowledge during the instructional period than students in comparison schools did, on average. We found an interaction between instruction and home-language status such that English-proficient students from language-minority homes improved more than English-proficient students from English-speaking homes. Limited English-proficiency students, however, did not realize gains equivalent to those of more proficient students from language-minority homes during the instructional period. We administered follow-up assessments in the fall after the instructional period ended and in the spring of the following year to determine how well students maintained and consolidated target academic words. Students in the intervention group maintained their relative improvements at both follow-up assessments.
The effects of learning American Sign Language on co-speech gesture
Authors: CASEY SHANNON , EMMOREY KAREN , LARRABEE HEATHER
Published: January 2012

Given that the linguistic articulators for sign language are also used to produce co-speech gesture, we examined whether one year of academic instruction in American Sign Language (ASL) impacts the rate and nature of gestures produced when speaking English. A survey study revealed that 75% of ASL learners (N = 95), but only 14% of Romance language learners (N = 203), felt that they gestured more after one year of language instruction. A longitudinal study confirmed this perception. Twenty-one ASL learners and 20 Romance language learners (French, Italian, Spanish) were filmed re-telling a cartoon story before and after one academic year of language instruction. Only the ASL learners exhibited an increase in gesture rate, an increase in the production of iconic gestures, and an increase in the number of handshape types exploited in co-speech gesture. Five ASL students also produced at least one ASL sign when re-telling the cartoon. We suggest that learning ASL may (i) lower the neural threshold for co-speech gesture production, (ii) pose a unique challenge for language control, and (iii) have the potential to improve cognitive processes that are linked to gesture.
The effect of dual task demands and proficiency on second language speech production
Authors: DECLERCK MATHIEU , KORMOS JUDIT
Published: January 2012

In this study we examined how the introduction of a parallel finger-tapping task influences second language (L2) speech encoding mechanisms and monitoring processes, and how the level of proficiency impacts the efficiency and accuracy of L2 performance under single and dual task conditions. The results indicate that imposing dual task demands had a negative effect on the accuracy of lexical selection and the efficiency of error-correction processes. We argue that this can be explained with reference to attentional bottleneck effects on lexical selection processes and on monitoring. The findings also reveal that the level of L2 competence influenced both the speed and the accuracy of speech encoding processes and the efficiency of monitoring.
Treatment gap in common mental disorders: the Singapore perspective
Authors: Chong S. A. , Abdin E. , Sherbourne C. , Vaingankar J. , Heng D. , Yap M. , Subramaniam M.
Published: January 2012

Aims.

The problem of wide treatment gaps in mental disorders is endemic world wide. The study aims to establish the treatment gap of common mental disorders in Singapore.

Methods.

A national sample of 6616 persons aged 18 years and above was surveyed with the World Mental Health Composite International Diagnostic Interview in which for each diagnostic module, respondents were asked a series of questions regarding treatment contact.

Results.

Treatment gap varied considerably between disorders; alcohol abuse had the largest treatment gap (96.2%), followed by obsessive compulsive disorder (89.8%) and alcohol dependence (88.3%). The disorder for which people were most likely to seek help was major depressive disorder. Women with dysthmia were more likely than men to seek help but this help seeking behavior was reversed among those with alcohol abuse and dependence. Age of onset was significantly associated with treatment contact with those who had an earlier age of onset less likely to have treatment contact than those with late age of onset for all disorders except obsessive compulsive disorder.

Conclusions.

Our findings suggest that treatment gaps are wide even in an economically developed country like Singapore and other than sociodemographic factors, cultural influences might play an important role in help seeking behavior.
Escape rates and variability constraints for high‐energy sodium sources at Mercury
Authors: Schmidt Carl A. , Baumgardner Jeffrey , Mendillo Michael , Wilson Jody K.
Published: January 2012

We present a 3‐D time‐dependent modeling of Mercury's extended sodium exosphere in the region of the distant tail. Recent simulations in support of the MESSENGER and BepiColombo missions have shown spatial distributions in Mercury's exosphere can be linked to specific source processes. Our model builds upon these efforts by concentrating on the escaping component of Mercury's surface‐bound exosphere to assess the wide‐field (7°) data described in the studies by Baumgardner et al. (2008) and Schmidt et al. (2010). Escape rates of several source processes in Mercury's exosphere are determined, and the effects of orbital motion, surface‐gas interactions, variable source rates, and spatially heterogeneous sources are explored. Our simulations demonstrate that both photon‐stimulated desorption and micrometeoroid impacts can result in a ∼20% loss of Mercury's sodium atmosphere, depending on orbital phase, and are jointly responsible for the observed comet‐like tail as driven by solar radiation pressure. For a constant supply of both these sources into the exosphere, the modeled average column density over Mercury's disc decreases by ∼1/3 at 70° true anomaly (the orbital position for peak escape), consistent with observations over many orbits.
Nonlinear estimation of geometric parameters in FEMs of volcano deformation: Integrating tomography models and geodetic data for Okmok volcano, Alaska
Authors: Masterlark Timothy , Feigl Kurt L. , Haney Matthew , Stone Jonathan , Thurber Clifford , Ronchin Erika
Published: January 2012

The internal structure, loading processes, and effective boundary conditions of a volcano control the deformation observed at the Earth's surface. Using finite element models (FEMs), we simulate the response due to a pressurized magma chamber embedded in a domain having a distribution of elastic material properties. We present the Pinned Mesh Perturbation method (PMP) to automate the mesh generation process in response to perturbations of the position of a simulated magma chamber within an FEM domain. Using InSAR‐observed deformation for the 1997 eruption of Okmok volcano, Alaska, as an example, we combine PMP with nested Monte Carlo methods to estimate a set of linear and nonlinear parameters that characterize the depressurization and location of the magma chamber beneath Okmok's caldera. The three‐dimensional FEMs used in the PMP method simulate the distribution of material properties of tomography models and account for the irregular geometry of the topography and bathymetry. The estimated depth of an assumed spherical magma chamber is 3527−54+55 m below sea level and is sensitive to the distribution of material properties. This depth is consistent with lithostatic pressure constraints and very long period tremor observations. The fit of this FEM to the InSAR data is a significant improvement, at the 95% confidence level, compared to the fit of a corresponding FEM having homogeneous material properties. The methods presented here allow us to construct deformation models that integrate tomography models with geodetic observations, in an effort to achieve a deeper understanding of active volcanoes.
Tidal asymmetry and velocity skew over tidal flats and shallow channels within a macrotidal river delta
Authors: Nidzieko N. J. , Ralston D. K.
Published: January 2012

It is often assumed that, in short, shallow estuaries, at leading order velocity and elevation are exactly out of phase, so that duration asymmetries in the rise and fall of the tide should be manifest as skewed velocities. We observed alternating ebb‐ and flood‐dominant velocity skew in response to the spring‐neap modulation of incident asymmetry generated by the mixed, mainly semidiurnal astronomical tides within the macrotidal Skagit River delta in Puget Sound, Washington. We describe three factors that may contribute to local asymmetries: (1) ebb dominance caused by phase lags between the surface gradient and local depth, (2) ebb dominance due to fluvial discharge, and (3) near‐bed flood dominance due to baroclinicity. Large spring tides led to greater frictionally generated phase lags and resulted in ebb‐dominant velocity skew. This ebb dominance caused by tidal drainage was reinforced by fluvial discharge across the tidal flat at lower‐low water. The baroclinic component of this discharge, however, produced flood‐dominant near‐bed velocity skew that countered the ebb dominance of the frictional effects. The balance of these processes depends strongly on the spring‐neap cycle, magnitude of river discharge, and position within the tidal flat and channel system. Our observations are notable in the context of previous studies describing these processes because our analyses indicate that these mechanisms are relevant over very short spatial scales of just a few kilometers and in very shallow systems.
The influences of ENSO on tropical cyclone activity in the Bay of Bengal during October–December
Authors: Girishkumar M. S. , Ravichandran M.
Published: January 2012

The El Niño–Southern Oscillation (ENSO) influence on tropical cyclone (TC) activity (frequency, genesis location, and intensity) in the Bay of Bengal (BoB) during the primary TC peak season (October–December) are studied for the period of 1993–2010. The study shows that during primary TC peak season, accumulated cyclone energy in the BoB is negatively correlated with Niño3.4 sea surface temperature anomaly. Under La Niña regime number of extreme TC cases (wind speed >64 kt) increases significantly in the BoB during the primary TC peak season. The analysis further shows that negative Indian Ocean dipole year is also favorable for extreme TC activity in the BoB during the primary TC peak season. The existence of low‐level cyclonic (anticyclonic) vorticity, enhanced (suppressed) convection, and high (low) tropical cyclonic heat potential (TCHP) in the BoB provides favorable (unfavorable) conditions for the TC activity under La Niña (El Niño) regimes together with weak vertical wind shear and high sea surface temperature (SST). The genesis location of TC shifts to the east (west) of 87°E in the BoB during La Niña (El Niño) regime due to the variability in convective activity. The probable reason for the intense TC during a La Niña regime is likely explained in terms of longer track for TCs over warm SST and high TCHP due to eastward shifting of genesis location together with other favorable conditions. The variability of Madden‐Julian Oscillation and its influence on TC activity in the BoB during La Niña and El Niño regime are also examined.
Hydrocarbon emissions characterization in the Colorado Front Range: A pilot study
Authors: Pétron Gabrielle , Frost Gregory , Miller Benjamin R. , Hirsch Adam I. , Montzka Stephen A. , Karion Anna , Trainer Michael , Sweeney Colm , Andrews Arlyn E. , Miller Lloyd , Kofler Jonathan , Bar‐Ilan Amnon , Dlugokencky Ed J. , Patrick Laura , Moore Charles T. , Ryerson Thomas B. , Siso Carolina , Kolodzey William , Lang Patricia M. , Conway Thomas , Novelli Paul , Masarie Kenneth , Hall Bradley , Guenther Douglas , Kitzis Duane , Miller John , Welsh David , Wolfe Dan , Neff William , Tans Pieter
Published: January 2012

The multispecies analysis of daily air samples collected at the NOAA Boulder Atmospheric Observatory (BAO) in Weld County in northeastern Colorado since 2007 shows highly correlated alkane enhancements caused by a regionally distributed mix of sources in the Denver‐Julesburg Basin. To further characterize the emissions of methane and non‐methane hydrocarbons (propane, n‐butane, i‐pentane, n‐pentane and benzene) around BAO, a pilot study involving automobile‐based surveys was carried out during the summer of 2008. A mix of venting emissions (leaks) of raw natural gas and flashing emissions from condensate storage tanks can explain the alkane ratios we observe in air masses impacted by oil and gas operations in northeastern Colorado. Using the WRAP Phase III inventory of total volatile organic compound (VOC) emissions from oil and gas exploration, production and processing, together with flashing and venting emission speciation profiles provided by State agencies or the oil and gas industry, we derive a range of bottom‐up speciated emissions for Weld County in 2008. We use the observed ambient molar ratios and flashing and venting emissions data to calculate top‐down scenarios for the amount of natural gas leaked to the atmosphere and the associated methane and non‐methane emissions. Our analysis suggests that the emissions of the species we measured are most likely underestimated in current inventories and that the uncertainties attached to these estimates can be as high as a factor of two.
Climatology and characteristics of stratospheric sudden warmings in the Whole Atmosphere Community Climate Model
Authors: de la Torre Laura , Garcia Rolando R. , Barriopedro David , Chandran Amal
Published: January 2012

Major stratospheric sudden warmings (SSW) occurring during Northern Hemisphere winter were identified in four runs of the Whole Atmosphere Community Climate Model (WACCM). Their characteristics are compared to those found by other authors using reanalysis data. The comparison shows that the frequency of occurrence of major SSW in the model is very similar to that found in reanalysis data, as is the occurrence of vortex splitting and displacement events. The main difference with respect to observations is that the modeled SSW are relatively longer lasting. WACCM simulates quite accurately some dynamical features associated with major SSW, despite the presence of outlier cases; however, the recently reported relationship between regional blocking and the type of SSW is only partially reproduced by WACCM. In general, the observed climatological and dynamical signatures of displacement SSW tend to be better reproduced by the model than those associated with splitting SSW. We also find that SSW in the model are often associated with an elevated polar cap stratopause, in agreement with recent observations. However, the simulations also show that there is not in general a close correspondence between major SSW and elevated polar cap stratopause events.
The wavelength dependence of the lunar phase curve as seen by the Lunar Reconnaissance Orbiter wide‐angle camera
Authors: Hapke Bruce , Denevi Brett , Sato Hiroyuki , Braden Sarah , Robinson Mark
Published: January 2012

The Lunar Reconnaissance Orbiter wide‐angle camera measured the bidirectional reflectances of two areas on the Moon at seven wavelengths between 321 and 689 nm and at phase angles between 0° and 120°. It is not possible to account for the phase curves unless both coherent backscatter and shadow hiding contribute to the opposition effect. For the analyzed highlands area, coherent backscatter contributes nearly 40% in the UV, increasing to over 60% in the red. This conclusion is supported by laboratory measurements of the circular polarization ratios of Apollo regolith samples, which also indicate that the Moon's opposition effect contains a large component of coherent backscatter. The angular width of the lunar opposition effect is almost independent of wavelength, contrary to theories of the coherent backscatter which, for the Moon, predict that the width should be proportional to the square of the wavelength. When added to the large body of other experimental evidence, this lack of wavelength dependence reinforces the argument that our current understanding of the coherent backscatter opposition effect is incomplete or perhaps incorrect. It is shown that phase reddening is caused by the increased contribution of interparticle multiple scattering as the wavelength and albedo increase. Hence, multiple scattering cannot be neglected in lunar photometric analyses. A simplified semiempirical bidirectional reflectance function is proposed for the Moon that contains four free parameters and that is mathematically simple and straightforward to invert. This function should be valid everywhere on the Moon for phase angles less than about 120°, except at large viewing and incidence angles close to the limb, terminator, and poles.
Inference of riverine nitrogen processing from longitudinal and diel variation in dual nitrate isotopes
Authors: Cohen Matthew J. , Heffernan James B. , Albertin Andrea , Martin Jonathan B.
Published: January 2012

Longitudinal and diel measurements of dual isotope composition (δ15N and δ18O) in nitrate (NO3‐N) were made in the Ichetucknee River, a large (∼8 m3 s−1), entirely spring‐fed river in North Florida, to determine whether isotopic variation can deconvolve assimilatory and dissimilatory removal. Comparing nitrate concentrations and isotope composition during the day and night we predicted (1) daytime declines in total fractionation due to low assimilatory fractionation and (2) diurnal variation in dual isotope coupling between 1:1 (assimilation) and 2:1 (denitrification). Five daytime longitudinal transects comprising 10 sampling stations showed consistent NO3‐N removal (25–35% of inputs) and modest fractionation (15εtotal between −2 and −6‰, enriching the residual nitrate pool). Lower fractionation (by ∼1‰) during two nighttime transects, suggests higher fractionation due to assimilation than denitrification. Total fractionation was significantly negatively associated with discharge, input [NO3‐N], N mass removal, and fractional water loss. Despite well‐constrained mass balance estimates that denitrification dominated total N removal, isotope coupling was consistently 1:1, both for longitudinal and diel sampling. Hourly samples on two dates at the downstream location showed significant diel variation in concentration ([NO3‐N] amplitude = 60 to 90 μg N L−1) and isotope composition (δ15N amplitude = −0.7‰ to −1.6‰). Total fractionation differed between day and night only on one date but estimated assimilatory fractionation assuming constant denitrification was highly variable and implausibly large (for N, 15ε = −2 to −25‰), suggesting that fractionation and removal due to denitrification is not diurnally constant. Pronounced counterclockwise hysteresis in the relationship between [NO3‐N] andδ15N suggests diel variation in N isotope dynamics. Together, low fractionation, isotope versus concentration hysteresis, and consistent 1:1 isotope coupling suggests that denitrification is controlled by NO3− diffusion into the benthic sediments, the length of which is mediated by riverine oxygen dynamics. While using dual isotope behavior to deconvolve removal pathways was not possible, isotope measurements did yield valuable information about riverine N cycling and transformations.
Determinations of plasmasphere electron content from a latitudinal chain of GPS stations
Authors: Mazzella Andrew J.
Published: January 2012

An extended application of a regional method (SCORPION) for calibration of GPS total electron content (TEC) measurements and plasmasphere electron content (PEC) determinations is described and demonstrated for a particular chain of GPS stations, in order to resolve the ambiguity between an omnipresent PEC contribution and the derived receiver system bias. Based on these calibrations and PEC determinations, a latitudinal profile of vertical TEC is presented for North American stations ranging from Alaska to central Mexico, with separate profiles for both the ionosphere (nominally to 1000 km altitude) and the plasmasphere. Determination of the local vertical PEC remedies a latitudinal TEC “sawtooth” feature arising from the standard conversion of slant TEC to equivalent vertical TEC at each station. Comparisons to other TEC methods and measurements, including SCORE, Jason‐1, and IONEX, are also presented. SCORE biases derived for simulated data confirm a latitudinal trend in its bias errors that is also evident in comparisons to SCORPION and Jason‐1. IONEX vertical TEC values are generally greater than the SCORPION vertical TEC values, although the associated comparisons of IONEX to SCORE results indicate that this is primarily a consequence of the conversion from slant TEC to equivalent vertical TEC without separating the ionosphere and plasmasphere components.
Crustal influx, indentation, ductile thinning and gravity redistribution in a continental wedge: Building a Moldanubian mantled gneiss dome with underthrust Saxothuringian material (European Variscan belt)
Authors: Chopin F. , Schulmann K. , Skrzypek E. , Lehmann J. , Dujardin J. R. , Martelat J. E. , Lexa O. , Corsini M. , Edel J. B. , Štípská P. , Pitra P.
Published: January 2012

The contribution of lateral forces, vertical load, gravity redistribution and erosion to the origin of mantled gneiss domes in internal zones of orogens remains debated. In the Orlica−Śnieżnik dome (Moldanubian zone, European Variscan belt), the polyphase tectono‐metamorphic history is initially characterized by the development of subhorizontal fabrics associated with medium‐ to high‐grade metamorphic conditions in different levels of the crust. It reflects the eastward influx of a Saxothuringian‐type passive margin sequence below a Teplá‐Barrandian upper plate. The ongoing influx of continental crust creates a thick felsic orogenic root with HP rocks and migmatitic orthogneiss. The orogenic wedge is subsequently indented by the eastern Brunia microcontinent producing a multiscale folding of the orogenic infrastructure. The resulting kilometre‐scale folding is associated with the variable burial of the middle crust in synforms and the exhumation of the lower crust in antiforms. These localized vertical exchanges of material and heat are coeval with a larger crustal‐scale folding of the whole infrastructure generating a general uplift of the dome. It is exemplified by increasing metamorphic conditions and younging of 40Ar/39Ar cooling ages toward the extruded migmatitic subdomes cored by HP rocks. The vertical growth of the dome induces exhumation by pure shear‐dominated ductile thinning laterally evolving to non‐coaxial detachment faulting, while erosion feeds the surrounding sedimentary basins. Modeling of the Bouguer anomaly grid is compatible with crustal‐scale mass transfers between a dense superstructure and a lighter infrastructure. The model implies that the Moldanubian Orlica−Śnieżnik mantled gneiss dome derives from polyphase recycling of Saxothuringian material.
Disruption of tubulin polymerization and cell proliferation by 1‐naphthylarsonic acid
Authors: Mahinpour Roya , Riazi Gholamhossein , Shokrgozar Mohammad A. , Sarbolouki Mohammad N. , Ahmadian Shahin , Douraghi Masoumeh , Alijanvand Hamid Hadi , Azadmanesh Kayhan , Heidari Maryam , Gheshlaghi Zahra Naghdi , Moosavi‐Movahedi Ali A.
Published: January 2012

Arsenical compounds exhibit a differential toxicity to cancer cells. Microtubules are a primary target of a number of anticancer drugs, such as arsenical compounds. The interaction of 1‐NAA (1‐naphthylarsonic acid) has been investigated on microtubule polymerization under in vitro and cellular conditions. Microtubules were extracted from sheep brain. Transmission electron microscopy was used to show microtubule structure in the presence of 1‐NAA. Computational docking method was applied for the discovery of ligand‐binding sites on the microtubular proteins. Proliferation of HeLa cells and HF2 (human foreskin fibroblasts) was measured by the MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide] assay method following their incubation with 1‐NAA. Fluorescence microscopic labelling was done with the help of α‐tubulin monoclonal antibody and Tunel kit was used to investigate the apoptotic effects of 1‐NAA on the HeLa cells. 1‐NAA inhibits the tubulin polymerization by the formation of abnormal polymers having high affinity to the inner cell wall.
The Intelligibility in Context Scale: Validity and Reliability of a Subjective Rating Measure
Authors: McLeod Sharynne , Harrison Linda J. , McCormack Jane
Published: January 2012

Purpose

To describe a new measure of functional intelligibility, the Intelligibility in Context Scale (ICS), and evaluate its validity, reliability, and sensitivity using 3 clinical measures of severity of speech sound disorder: (a) percentage of phonemes correct (PPC), (b) percentage of consonants correct (PCC), and (c) percentage of vowels correct (PVC).

Method

Speech skills of 120 preschool children (109 with parent-/teacher-identified concern about how they talked and made speech sounds and 11 with no identified concern) were assessed with the Diagnostic Evaluation of Articulation and Phonology (Dodd, Hua, Crosbie, Holm, & Ozanne, 2002). Parents completed the 7-item ICS, which rates the degree to which children’s speech is understood by different communication partners (parents, immediate family, extended family, friends, acquaintances, teachers, and strangers) on a 5-point scale.

Results

Parents' ratings showed that most children were
always
(5) or
usually
(4) understood by parents, immediate family, and teachers, but only
sometimes
(3) by strangers. Factor analysis confirmed the internal consistency of the ICS items; therefore, ratings were averaged to form an overall intelligibility score. The ICS had high internal reliability (α = .93), sensitivity, and construct validity. Criterion validity was established through significant correlations between the ICS and PPC (
r
= .54), PCC (
r
= .54), and PVC (
r
= .36).

Conclusions

The ICS is a promising new measure of functional intelligibility. These data provide initial support for the ICS as an easily administered, valid, and reliable estimate of preschool children’s intelligibility when speaking with people of varying levels of familiarity and authority.
Item-Level Psychometrics and Predictors of Performance for Spanish/English Bilingual Speakers on
An Object and Action Naming Battery
Authors: Edmonds Lisa A. , Donovan Neila J.
Published: January 2012

Purpose

There is a pressing need for psychometrically sound naming materials for Spanish/English bilingual adults. To address this need, in this study the authors examined the psychometric properties of An Object and Action Naming Battery (An O&A Battery; Druks & Masterson, 2000) in bilingual speakers.

Method

Ninety-one Spanish/English bilinguals named O&A Battery items in English and Spanish. Responses underwent a Rasch analysis. Using correlation and regression analyses, the authors evaluated the effect of psycholinguistic (e.g., imageability) and participant (e.g., proficiency ratings) variables on accuracy.

Results

Rasch analysis determined unidimensionality across English and Spanish nouns and verbs and robust item-level psychometric properties, evidence for content validity. Few items did not fit the model, there were no ceiling or floor effects after uninformative and misfit items were removed, and items reflected a range of difficulty. Reliability coefficients were high, and the number of statistically different ability levels provided indices of sensitivity. Regression analyses revealed significant correlations between psycholinguistic variables and accuracy, providing preliminary construct validity. The participant variables that contributed most to accuracy were proficiency ratings and time of language use.

Conclusions

Results suggest adequate content and construct validity of O&A items retained in the analysis for Spanish/English bilingual adults and support future efforts to evaluate naming in older bilinguals and persons with bilingual aphasia.
Developing a Single Comparison Stimulus for Matching Breathy Voice Quality
Authors: Patel Sona , Shrivastav Rahul , Eddins David A.
Published: January 2012

Purpose

In this experiment, a single comparison stimulus was developed as a reference in a perceptual matching task for the quantification of breathy voice quality. Perceptual judgments of a set of synthetic voice samples were compared to previous data obtained using multiple comparison stimuli “customized” for different voices (Patel, Shrivastav, & Eddins, 2010).

Method

Five male and 5 female samples of the vowel /a/ were selected from the Kay Elemetrics Disordered Voice Database and resynthesized using a Klatt synthesizer. Eleven samples were created for each base voice by manipulating the aspiration noise level. Five samples from each continuum were evaluated in a perceptual matching task in which a single sawtooth and noise comparison stimulus was used to obtain breathiness judgments. Linear regression was used to compare measurements obtained using the new comparison stimulus against the customized comparison stimuli.

Results

Results indicated that the noncustomized sawtooth comparison provides reliability and perceptual distances between stimuli similar to those obtained using customized comparison stimuli.

Conclusion

A single-variable matching task using a single comparison stimulus can be used to obtain perceptual estimates of breathiness across voices and experiments in a laboratory setting. This technique will help develop models of voice-quality perception.
Measuring Speech Recognition in Children With Cochlear Implants in a Virtual Classroom
Authors: Neuman Arlene C. , Wroblewski Marcin , Hajicek Joshua , Rubinstein Adrienne
Published: January 2012

Purpose

To determine the feasibility of using a virtual auditory test material to evaluate reverberation and noise effects on speech recognition of pediatric cochlear implant (CI) users and to compare their performance with that of children with normal hearing.

Method

Virtual test materials representing nonreverberant and reverberant environments were used to measure speech recognition of 7 children with CIs in quiet and in noise, and of 18 children with normal hearing in the quiet condition. Performance of CI users in noise (signal-to-noise ratio resulting in 50% performance) was compared to normative data from a previous study (Neuman, Wroblewski, Hajicek, & Rubinstein, 2010). For CI users, stimuli were sent directly to the CI speech processor via auxiliary input, whereas children with normal hearing were tested using insert phones.

Results

The speech recognition of children with CIs decreased significantly in the reverberant condition. There were individual differences in susceptibility to reverberation. Children with CIs also required higher signal-to-noise ratios than children with normal hearing in the reverberant condition.

Conclusion

Direct connect testing with reverberant test materials allows assessment of speech recognition under conditions typical of classrooms and could be useful in identifying children with CIs whose performance decreases significantly in the presence of reverberation and noise.
Resolution limit for DNA barcodes in the Odijk regime
Authors: Wang Yanwei , Reinhart Wes F. , Tree Douglas R. , Dorfman Kevin D.
Published: January 2012

We develop an approximation for the probability of optically resolving two fluorescent labels on the backbone of a DNA molecule confined in a nanochannel in the Odijk regime as a function of the fluorescence wavelength, channel size, and the properties of the DNA (persistence length and effective width). The theoretical predictions agree well with equivalent data produced by Monte Carlo simulations of a touching wormlike bead model of DNA in a high ionic strength buffer. Although the theory is only strictly valid in the limit where the effective width of the nanochannel is small compared with the persistence length of the DNA, simulations indicate that the theoretical predictions are reasonably accurate for channel widths up to two-thirds of the persistence length. Our results quantify the conjecture that DNA barcoding has kilobase pair resolution—provided the nanochannel lies in the Odijk regime.