bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive Skills Development among Transfer College Students: An Analysis by Student Gender and Race
Authors: Edens David , Dy Heather , Dalske James , Strain Cassandra
Published: May 2015

The purpose of the study is to improve the understanding of transfer college students, by examining the patterns in and predictors of cognitive skills development among transfer college students. Moreover, this study examined how such patterns and predictors differ by student’s gender and race within this population. Results found that men and women transfer students have differing cognitive skills gains after transferring to a 4-year institution. Results also indicated that there are differences in the cognitive skills gained in college by transfer students from various races. Finally, using regression analysis, models were developed to predict the variance in cognitive skills development for transfer students. Models were able to 33% and 46% of the variance in cognitive skills gains, when evaluated by gender or ethnicity.
Lifetime risk and characterization of red blood cell alloimmunization in chronically transfused patients with sickle cell disease
Authors: I Woldie , P Swerdlow , M.H Bluth , U Mohammad , E Landolfi , S Chaudrhy , G Dyson , Malley B.A O
Published: May 2015

Aims: Patients with sickle cell disease (SCD) are often exposed to multiple units of blood transfusions predisposing them to the development of alloantibodies. Alloantibodies make subsequent transfusion difficult, costly and could also result in life-threatening hemolysis. The aim of this study is to estimate and characterize alloantibodies developing over a life-time in patients with sickle cell disease who are on chronic red cell transfusion.
Methods: Retrospective data were obtained from the electronic medical record and sunquest transfusion record of the DMC for a total of 121 patients with SCD aged 18 years and older who were on chronic red cell exchange transfusion. Data on demographics, blood group, genotype, total number of units transfused over lifetime, presence and type of alloantibodies identified was collected and analyzed.
Results: The median age of the studied patients was 33 years with a male to female ratio of 0.73. Almost all (>95%) patients had homozygous SCD. A total of 67,586 units were transfused for the 121 patients over a lifetime approximating an average of 559 units transfused per patient. Alloantibodies were identified in 68 of the 121 patients (56.2%). The most common antibody identified was E (27%) followed by K (23%) and C (12%). Overall, antibodies against the Rh system (E, C, D and e) accounted for 39% of the identified antibodies.
Conclusion: These data demonstrate a high lifetime rate of alloimmunization for patients with SCD on chronic red cell exchange transfusion. Understanding the nature of alloantibody development in chronically transfused SCD patients can help foster appropriate blood utilization paradigms, and develop preventive strategies.
Statistical Power in theJournal of Research in Music Education(2000–2010): A Retrospective Power Analysis
Authors: Overland Corin T.
Published: May 2015

During the last half of the 20th century, researchers became increasingly aware of a tendency in much social science research to lack sufficient statistical power. Low power can cause studies to be unable to reliably detect true effects in a population (Type II error) and to overestimate the practical significance of small effects when they are detected. Despite cautionary writings and the widespread availability of helpful computational tools, systemically underpowered research persists in the majority of contemporary academic journals. While the Journal of Research in Music Education is arguably the profession’s most prominent platform for empirical research, the degree to which this issue may be present has not yet been examined. Results found that the research articles published in the journal between 2000-2010 share similarities with other prominent journals in education and educational psychology in that, on average, the statistical power of the designs fell well below commonly accepted thresholds. Survey research in music education generally fared the best, being more adequately powered (.72) than many other academic disciplines, although still below the de facto standard of .80. By contrast, the average power of designs involving the manipulation of experimental conditions was much lower (.55). These figures represent best-case scenarios. Reports often did not contain all relevant information necessary to determine some common hidden drains to power, requiring some concessions to be made during calculation that likely overestimate the final results. Suggestions for maximizing statistical power are offered as well as a discussion of alternatives to classical null hypotheses significance testing.
A Rational Approximation for Efficient Computation of the Voigt Function in Quantitative Spectroscopy
Authors: Abrarov Sanjar M. , Quine Brendan M.
Published: May 2015

We present a rational approximation for rapid and accurate computation of the Voigt function, obtained by sampling and residue calculus. The computational test reveals that with only $16$ summation terms this approximation provides average accuracy ${10^{ - 14}}$ over a wide domain of practical interest  $0 < x < 40,000$ and ${10^{ - 4}} < y < {10^2}$ for applications using the HITRAN molecular spectroscopic database. The proposed rational approximation takes less than half the computation time of that required by Weideman\text{'}s rational approximation. Algorithmic stability is achieved due to absence of the poles at $y \geqslant 0$ and $ - \infty  < x < \infty $.
Motion-Based Gesture Recognition Algorithms for Robot Manipulation
Authors: Marasović Tea , Papić Vladan , Marasović Jadranka
Published: May 2015

The prevailing trend of integrating inertial sensors in consumer electronics devices has inspired research on new forms of human-computer interaction utilizing hand gestures, which may be set-up on mobile devices themselves. At present, motion gesture recognition is intensely studied, with various recognition techniques being employed and tested. This paper provides an in-depth, unbiased comparison of different algorithms used to recognize gestures based primarily on the single 3D accelerometer recordings. The study takes two of the most popular and arguably the best recognition methods currently in use - dynamic time warping and hidden Markov model - and sets them against a relatively novel approach founded on distance metric learning. The three selected algorithms are evaluated in terms of their overall performance, accuracy, training time, execution time and storage efficacy. The optimal algorithm is further implemented in a prototype user application, aimed to serve as an interface for controlling the motion of a toy robot via gestures made with a smartphone.
Understanding Human Hand Gestures for Learning Robot Pick-and-Place Tasks
Authors: Lin Hsien-I , Chiang Y. P.
Published: May 2015

Programming robots by human demonstration is an intuitive approach, especially by gestures. Because robot pick-and-place tasks are widely used in industrial factories, this paper proposes a framework to learn robot pick-and-place tasks by understanding human hand gestures. The proposed framework is composed of the module of gesture recognition and the module of robot behaviour control. For the module of gesture recognition, transport empty (TE), transport loaded (TL), grasp (G), and release (RL) from Gilbreth's therbligs are the hand gestures to be recognized. A convolution neural network (CNN) is adopted to recognize these gestures from a camera image. To achieve the robust performance, the skin model by a Gaussian mixture model (GMM) is used to filter out non-skin colours of an image, and the calibration of position and orientation is applied to obtain the neutral hand pose before the training and testing of the CNN. For the module of robot behaviour control, the corresponding robot motion primitives to TE, TL, G, and RL, respectively, are implemented in the robot. To manage the primitives in the robot system, a behaviour-based programming platform based on the Extensible Agent Behavior Specification Language (XABSL) is adopted. Because the XABSL provides the flexibility and re-usability of the robot primitives, the hand motion sequence from the module of gesture recognition can be easily used in the XABSL programming platform to implement the robot pick-and-place tasks. The experimental evaluation of seven subjects performing seven hand gestures showed that the average recognition rate was 95.96%. Moreover, by the XABSL programming platform, the experiment showed the cube-stacking task was easily programmed by human demonstration.
Robotic Surgery – A Personal View of the Past, Present and Future
Authors: Davies Brian
Published: May 2015

Research into robotic surgery has been undertaken for over 25 years. In that period a small number of companies have been formed to exploit this research and have undertaken clinical trials on patients. However, far fewer clinical applications have been undertaken than would have been expected from the level of research activity. This paper puts forward a number of reasons for this, many of which are not to do with the technology but are a consequence of the clinical and business environments. Recommendations are provided that will hopefully increase the number of clinical systems being applied. Some predictions are made for the future which should increase the number of commercial systems and thus achieve patient benefits.
Umělecký text v didaktickém aparátu čítanek pro primární školy: výsledky analýzy
Authors: Lavičková Hana
Published: May 2015

Cílem empirické studie je představit výsledky obsahové analýzy podob zadání didaktického aparátu čítanek určených pro žáky primární školy z hlediska jeho směřování k naplnění přímé práce žáků s uměleckými texty zařazenými do čítanek. V první části studie poukazujeme na specifickou roli čítanek při rozvíjení estetickovýchovného pojetí školní literární výchovy. Druhá část je věnována literárněvědným, literárnědidaktickým a kurikulárním východiskům výzkumu. Třetí část popisuje současný stav poznání v oblasti výzkumu čítanek. Ve čtvrté části představujeme metodologii výzkumu; výzkumný vzorek tvořil didaktický aparát 2 ucelených čítankových řad (8 čítanek určených pro 2.–5. ročník primární školy) sestávající z 3450 otázek, úkolů a námětů k činnostem. V páté části prezentujeme výsledky výzkumu, které poukázaly na některé společné tendence a výrazné rozdíly mezi zkoumanými čítankami. Zjistili jsme, že na práci žáků s uměleckým textem se nejvýrazněji orientují didaktické aparáty čítanek pro 4. a 5. ročník primární školy, nejméně didaktické aparáty čítanek pro 2. ročník primární školy. Z výsledků vyplývá, že zastoupení jednotlivých oblastí uměleckého textu je ve zkoumaných čítankách značně nerozmanité. V didaktickém aparátu čítanek převažují otázky, úkoly a náměty k činnostem zaměřené na tematiku a smysl uměleckého textu. Na základě zjištěných výsledků předkládáme v závěru studie doporučení pro tvorbu čítanek.
Možnosti využití metody eyetrackingu ve výzkumu kompetencí historického myšlení na příkladu analýzy ikonografického materiálu
Authors: Labischová Denisa
Published: May 2015

Empirická studie pojednává o perspektivách využití metody eyetrackingu, založené na sledování očních pohybů při percepci verbálního a ikonického textu, a přináší výsledky předvýzkumu z roku 2014, jehož cílem bylo ověřit výzkumný nástroj pro zkoumání vlivu konkrétního způsobu strukturace analýzy historické karikatury na kvalitu její interpretace respondenty. V první kapitole jsou vymezena teoretická východiska (význam historických pramenů v procesu rozvíjení kompetencí historického myšlení) a jsou zde uvedeny možnosti uplatnění eyetrackingu v pedagogickém výzkumu. Ve druhé kapitole jsou popsány použité metody sběru a zpracování dat. Zvolen byl smíšený výzkumný přístup, zahrnující analýzu audiozáznamů slovních odpovědí studentů a statistických i vizualizovaných dat získaných elektronickým měřením. Testováno bylo 23 studentů učitelství z Moravskoslezského kraje. Ve třetí kapitole jsou prezentována výzkumná zjištění – návrh kategoriálního systému pro interpretaci karikatury, vizualizace dat v podobě heatmap, gaze opacity map a gaze plots a nejvýznamnější kvantitativní data (rozdíly v četnosti a délce očních fixací v průběhu testu). Předvýzkum ukázal, že eyetracking může poskytnout jinými metodami obtížně zjistitelné informace o percepčních strategiích uplatňovaných při interpretaci textu. Výsledky naznačují, že v případě didakticky strukturované analýzy historické karikatury dosahují respondenti vyšší úrovně interpretace než při analýze nestrukturované, kdy se slovní odpovědi omezují převážně na zobrazené osobnosti a jsou opomíjeny důležité symboly, obrazové kódy i širší historický kontext.
Controversy and Diversity: LGBTQ Titles in Academic Library Youth Collections
Authors: Williams Virginia Kay , Deyoe Nancy
Published: May 2015

Academic libraries supporting education and library science programs collect youth literature to support courses that teach students to evaluate and use books with children and teenagers. Although children’s and young adult literature with lesbian, gay, bisexual, transgender, and queer (LGBTQ) content is often controversial, this literature is being discussed in both the education and library literature. This paper discusses the literature on LGBTQ youth literature, explores the extent to which academic libraries supporting education and library science programs collect recently published LGBTQ youth literature, and concludes that academic librarians responsible for youth collections should evaluate their LGBTQ holdings to ensure that they are meeting the needs of future teachers and educators for access to these books. The paper offers suggestions for assessing collections, locating LGBTQ youth titles, and updating selection procedures to build a more inclusive collection.
Book Review: The Preservation Management Handbook: A 21st–Century Guide for Libraries, Archives, and Museums
Authors: Drewes Jeanne
Published: May 2015

A recent issue of Preservation, Digital Technology & Culture was devoted to preservation education and presented the conference papers from the 2011 University of Michigan “Symposium of Preservation Educators.” Paul Conway, the convener in the opening session, provided the key to the importance of the program: “In the cultural heritage sector of libraries, archives, and museums, the ongoing transition from analog to digital technologies as source, medium and technique has accelerated the pace of the knowledge required for one to be an effective preservationist, and it has complicated the transfer of knowledge from experts to students.”
Book Review: Linked Data for Libraries, Archives, and Museums: How to Clean, Link and Publish Your Metadata
Authors: Romano Lisa
Published: May 2015

For the past few years, librarians have heard how Linked Data will be the future of bibliographic data. Linked Data for Libraries, Archives, and Museums: How to Clean, Link and Publish Your Metadata tries to make sense of the hype. The goal of this book is to introduce “the process of making your collections available, from the arduous processes of cleaning and connecting to publishing it for the world” (xiv). Specifically, this book describes metadata standards including Linked Data, associated tools and technologies, and the sustainability of metadata and technologies. The authors critically evaluate various options that can be used to clean, enrich, and publish metadata along with the history, advantages, and disadvantages of each.
Evaluating the Physical Effects of Sport Climbing on Archaeological Sites
Authors: Henrikson Lael Suzann , Camp Amanda M.
Published: May 2015

A statistical analysis was conducted to evaluate whether sport climbing has contributed to de-vegetation at the base of basalt cliffs within the American Falls Archaeological District (AFAD), located along the Snake River in southern Idaho and currently managed by the Bureau of Land Management (BLM) and the U.S. Bureau of Reclamation (USBR). The increasing popularity of sport climbing has created challenging conflicts between public recreation and cultural resource protection. The loss of vegetation in the AFAD’s dune environment, from both recreation and natural processes, has already displaced and damaged significant archaeological resources. The Access Fund acknowledges that staging areas at the base of climbs are susceptible to vegetation loss and erosion, especially in arid environments. Since numerous “bare spots” occur under and along basalt cliffs throughout the AFAD, this analysis was designed to quantify these un-vegetated areas. The results of the analysis, which indicate that bare spots directly associated with climbing walls are significantly larger than those that appear to be natural, will be applied in management decisions regarding the protection and preservation of federally managed cultural resources within the AFAD. Hopefully, these results will assist other land management agencies in making proactive decisions regarding recreational use in archaeologically sensitive areas.
User Guide for Luminescence Sampling in Archaeological and Geological Contexts
Authors: Nelson Michelle S. , Gray Harrison J. , Johnson Jack A. , Rittenour Tammy M. , Feathers James K. , Mahan Shannon A.
Published: May 2015

Luminescence dating provides a direct age estimate of the time of last exposure of quartz or feldspar minerals to light or heat and has been successfully applied to deposits, rock surfaces, and fired materials in a number of archaeological and geological settings. Sampling strategies are diverse and can be customized depending on local circumstances, although all sediment samples need to include a light-safe sample and material for dose-rate determination. The accuracy and precision of luminescence dating results are directly related to the type and quality of the material sampled and sample collection methods in the field. Selection of target material for dating should include considerations of adequacy of resetting of the luminescence signal (optical and thermal bleaching), the ability to characterize the radioactive environment surrounding the sample (dose rate), and the lack of evidence for post-depositional mixing (bioturbation in soils and sediment). Sample strategies for collection of samples from sedimentary settings and fired materials are discussed. This paper should be used as a guide for luminescence sampling and is meant to provide essential background information on how to properly collect samples and on the types of materials suitable for luminescence dating.
Formatting Film Studies
Authors: Wasson Haidee
Published: May 2015

Film studies is currently undergoing a needed and healthy expansion of methodologies and critical approaches, including media, cultural and technology studies. This is crucial not just for examining cinemas present but also its past. Using format theory, this article opens up our understanding of what cinema has been, rather than what it should have been. It does this by documenting the minor technological footprint of movie theatres when compared to the expansive one consisting of 8mm and 16mm small-gauge projectors. In the United States by 1980, these portable devices,outnumbered commercial theatres by an estimated factor of 1000:1.
Tinnitus and hyperacusis involve hyperactivity and enhanced connectivity in auditory-limbic-arousal-cerebellar network
Authors: Chen Yu-Chen , Li Xiaowei , Liu Lijie , Wang Jian , Lu Chun-Qiang , Yang Ming , Jiao Yun , Zang Feng-Chao , Radziwon Kelly , Chen Guang-Di , Sun Wei , Krishnan Muthaiah Vijaya Prakash , Salvi Richard , Teng Gao-Jun
Published: May 2015

Hearing loss often triggers an inescapable buzz (tinnitus) and causes everyday sounds to become intolerably loud (hyperacusis), but exactly where and how this occurs in the brain is unknown. To identify the neural substrate for these debilitating disorders, we induced both tinnitus and hyperacusis with an ototoxic drug (salicylate) and used behavioral, electrophysiological, and functional magnetic resonance imaging (fMRI) techniques to identify the tinnitus–hyperacusis network. Salicylate depressed the neural output of the cochlea, but vigorously amplified sound-evoked neural responses in the amygdala, medial geniculate, and auditory cortex. Resting-state fMRI revealed hyperactivity in an auditory network composed of inferior colliculus, medial geniculate, and auditory cortex with side branches to cerebellum, amygdala, and reticular formation. Functional connectivity revealed enhanced coupling within the auditory network and segments of the auditory network and cerebellum, reticular formation, amygdala, and hippocampus. A testable model accounting for distress, arousal, and gating of tinnitus and hyperacusis is proposed.
Large‐scale jets in the magnetosheath and plasma penetration across the magnetopause: THEMIS observations
Authors: Dmitriev A. V. , Suvorova A. V.
Published: May 2015

Time History of Events and Macroscale Interactions during Substorms multipoint observation of the plasma and magnetic fields, conducted simultaneously in the dayside magnetosheath and magnetosphere, were used to collect 646 large‐scale magnetosheath plasma jets interacting with the magnetopause. The jets were identified as dense and fast streams of the magnetosheath plasma whose energy density is higher than that of the upstream solar wind. The jet interaction with the magnetopause was revealed from sudden inward motion of the magnetopause and an enhancement in the geomagnetic field. The penetration was determined as appearance of the magnetosheath plasma against the background of the hot magnetospheric particle population. We found that almost 60% of the jets penetrated through the magnetopause. Vast majority of the penetrating jets was characterized by high velocities V > 220 km/s and kinetic βk > 1 that corresponded to a combination of finite Larmor radius effect with a mechanism of impulsive penetration. The average plasma flux in the penetrating jets was found to be 1.5 times larger than the average plasma flux of the solar wind. The average rate of jet‐related penetration of the magnetosheath plasma into the dayside magnetosphere was estimated to be ~1029 particles/d. The rate varies highly with time and can achieve values of 1.5 × 1029 particles/h that is comparable with estimates of the total amount of plasma entering the dayside magnetosphere.
Styles of rifting and fault spacing in numerical models of crustal extension
Authors: Sharples W. , Moresi L.‐N. , Jadamec M. A. , Revote J.
Published: May 2015

Extension of the Earth's crust can result in differing styles of rifting, such as horst‐and‐graben, half‐graben, metamorphic core complexes and areas of distributed crustal thinning. Faulting patterns can range from either being distributed to highly localized. Observations indicate that the factors controlling the extensional deformation, symmetry, and fault spacing include rheological aspects such as the yielding mechanism and strain softening, and physical aspects such as initial heterogeneities and the strength of the lower crust compared to the upper crust. Time‐dependent numerical models of extension are presented, which investigate the influence of the yielding mechanism, lower crust strength, strain weakening, and initial heterogeneity in the crust have on (a) the style of rifting, (b) fault spacing, and (c) integrated strength in the upper crust. Models with an anisotropic yielding mechanism result in more realistic lithospheric strength profiles, slip plane angle distributions, and fault interaction than models with an isotropic yielding mechanism. Heterogeneity type and yielding mechanisms have the largest effect on the resulting symmetry of deformation, whereas the amount of strain weakening has the greatest influence on asymmetry. The likelihood of the metamorphic core complex mode occurring is primarily controlled by lower crust strength. Crustal thinning is encouraged by both low amounts of strain weakening and a strong lower crust. Lower crust viscosity exerts the primary control on whether the resulting deformation is distributed or localized. The degree of strain weakening has the largest influence on the average strength of the upper crust and the slope of the strength profile in the upper crust.
Seasonal and diurnal variability in historical warming due to the urbanization of Hokkaido, Japan
Authors: Sugimoto Shiori , Sato Tomonori , Sasaki Tomonori
Published: May 2015

The influence of historical urbanization on warming trends observed on Hokkaido Island (Japan) is discussed with an emphasis on seasonally and diurnally differential responses of air temperature to urban effects. Two numerical experiments using past and current land use scenarios successfully simulated the observed temperature trends, showing a greater rate of warming in winter than in summer and a greater increase in daily minimum than daily maximum temperatures. The results suggest that seasonal and diurnal variations in the thermal structure of the planetary boundary layer play a leading role in determining the warming rate of surface air. Under strongly stable stratification, anomalous heating within the urban canopy dissipates into a near‐surface shallow layer, resulting in increased daily minimum temperatures during winter. In summer, however, anomalous urban heating due to increased Bowen ratios is attenuated by vertical mixing in the convective daytime boundary layer, suppressing the impact of urban heating on surface warming.
Effects of temperature and precipitation on snowpack variability in the Central Rocky Mountains as a function of elevation
Authors: Sospedra‐Alfonso Reinel , Melton Joe R. , Merryfield William J.
Published: May 2015

We employ a regression‐based methodology to study the impact of temperature and precipitation on snowpack variability as a function of elevation in the Central Rocky Mountains. Because of the broad horizontal coverage and thermal heterogeneity of the measurement sites employed, we introduce an elevation correction based on the sites' climatological temperature. For the elevation range investigated (1295–2256 m), and assuming an average atmospheric lapse rate of −6.5°C/km, we find a mostly linear relationship between effective elevation and correlation of temperature or precipitation with snow water equivalent and snowpack duration. We estimate a threshold elevation, 1560 ± 120 m, below (above) which temperature (precipitation) is the main driver of the snowpack. This threshold elevation is robust under a range of assumed atmospheric lapse rates. Locations below this elevation are likely to be affected by projected rising temperatures, with important effects on ecosystems and economic activities dependent on snow.
Scale‐dependent effects of solar radiation patterns on the snow‐dominated hydrologic response
Authors: Comola F. , Schaefli B. , Ronco P. Da , Botter G. , Bavay M. , Rinaldo A. , Lehning M.
Published: May 2015

Solar radiation is a dominant driver of snowmelt dynamics and streamflow generation in alpine catchments. A better understanding of how solar radiation patterns affect the hydrologic response is needed to assess when calibrated temperature‐index models are likely to be spatially transferable for ecohydrological applications. We induce different solar radiation patterns in a Swiss Alpine catchment through virtual rotations of the digital elevation model. Streamflow simulations are performed at different spatial scales through a spatially explicit hydrological model coupled to a physically based snow model. Results highlight that the effects of solar radiation patterns on the hydrologic response are scale dependent, i.e., significant at small scales with predominant aspects and weak at larger scales where aspects become uncorrelated and orientation differences average out. Such scale dependence proves relevant for the spatial transferability of a temperature‐index model, whose calibrated degree‐day factors are stable to different solar radiation patterns for catchment sizes larger than the aspect correlation scale.
Interhemispheric transit time distributions and path‐dependent lifetimes constrained by measurements of SF6, CFCs, and CFC replacements
Authors: Holzer Mark , Waugh Darryn W.
Published: May 2015

We constrain tropospheric transport from Northern Hemisphere midlatitudes to the Southern Hemisphere (SH) surface using measurements of SF6, CFCs, and CFC replacement gases and a novel maximum‐entropy‐based inversion approach. We provide the first estimate of the width Δ of the tropospheric interhemispheric transit time distribution (TTD). We find that Δ has a value of ∼1.3 years that varies little with SH latitude, compared to the mean transit time Γ that increases from ∼1.1 years in the SH tropics to ∼1.4 years at the South Pole. The TTD shape parameter Δ/Γ is thus larger in the SH tropics than at middle and high SH latitudes. Our analysis introduces a simple path‐dependent lifetime that parameterizes chemical losses. The path‐dependent lifetimes are estimated for CFC replacements, and systematic differences between path‐dependent and global lifetimes are interpreted. The path‐dependent lifetimes have the potential to provide new observational constraints on tropospheric and stratospheric loss processes.
The continental drift convection cell
Authors: Whitehead J. A. , Behn Mark D.
Published: May 2015

Continents on Earth periodically assemble to form supercontinents and then break up again into smaller continental blocks (the Wilson cycle). Previous highly developed numerical models incorporate fixed continents while others indicate that continent movement modulates flow. Our simplified numerical model suggests that continental drift is fundamental. A thermally insulating continent is anchored at its center to mantle flow on an otherwise stress‐free surface for infinite Prandtl number cellular convection with constant material properties. Rayleigh numbers exceed 107, while continent widths and chamber lengths approach Earth's values. The Wilson cycle is reproduced by a unique, rugged monopolar “continental drift convection cell.” Subduction occurs at the cell's upstream end with cold slabs dipping at an angle beneath the moving continent (as found in many continent/subduction regions on Earth). Drift enhances vertical heat transport up to 30%, especially at the core‐mantle boundary, and greatly decreases lateral mantle temperature differences.
Hemispheric asymmetry of subauroral ion drifts: Statistical results
Authors: Zhang Xiao‐Xin , He Fei , Wang Wenbin , Chen Bo
Published: May 2015

A large database of more than 18,000 subauroral ion drift (SAID) events from DMSP observations from 1987 to 2012 is used to systematically investigate the features of SAID. SAID occurs mostly at ~62°/−60° magnetic latitude (MLAT) and ~22:15/22:45 magnetic local time (MLT) for geomagnetically quiet conditions and at ~58°/−56° MLAT and ~22:15/22:45 MLT for geomagnetically disturbed conditions in the North Hemisphere (NH)/South Hemisphere (SH), respectively. Significant north‐south asymmetries in SAID occurrence, shape, and geomagnetic activity variations are found in this statistical study. The latitudinal width of a SAID is larger in the NH than in the SH. An interesting finding of this work is that the SAID occurrence probability peaks have an ~180° difference in longitude between the two hemispheres in the geographic coordinates for both geomagnetically quiet and disturbed conditions. The SAID width peaks in almost the same geomagnetic meridian zone with a geomagnetic longitude of ~80°–120° in both hemispheres. Significant hemispheric asymmetries and spike signatures with sharp dips are found in all the latitudinal profiles of the horizontal velocities of SAIDs. The SAID is highly correlated to geomagnetic activity, indicating that the location and evolution of the SAID might be influenced by global geomagnetic activity, auroral dynamics, and the dynamics of ring currents.
Modular model for Mercury's magnetospheric magnetic field confined within the average observed magnetopause
Authors: Korth Haje , Tsyganenko Nikolai A. , Johnson Catherine L. , Philpott Lydia C. , Anderson Brian J. , Al Asad Manar M. , Solomon Sean C. , McNutt Ralph L.
Published: May 2015

Accurate knowledge of Mercury's magnetospheric magnetic field is required to understand the sources of the planet's internal field. We present the first model of Mercury's magnetospheric magnetic field confined within a magnetopause shape derived from Magnetometer observations by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft. The field of internal origin is approximated by a dipole of magnitude 190 nT RM3, where RM is Mercury's radius, offset northward by 479 km along the spin axis. External field sources include currents flowing on the magnetopause boundary and in the cross‐tail current sheet. The cross‐tail current is described by a disk‐shaped current near the planet and a sheet current at larger (≳ 5 RM) antisunward distances. The tail currents are constrained by minimizing the root‐mean‐square (RMS) residual between the model and the magnetic field observed within the magnetosphere. The magnetopause current contributions are derived by shielding the field of each module external to the magnetopause by minimizing the RMS normal component of the magnetic field at the magnetopause. The new model yields improvements over the previously developed paraboloid model in regions that are close to the magnetopause and the nightside magnetic equatorial plane. Magnetic field residuals remain that are distributed systematically over large areas and vary monotonically with magnetic activity. Further advances in empirical descriptions of Mercury's magnetospheric external field will need to account for the dependence of the tail and magnetopause currents on magnetic activity and additional sources within the magnetosphere associated with Birkeland currents and plasma distributions near the dayside magnetopause.
Fission Gas and Bias‐Driven Swelling of Nuclear Fuels
Authors: Rest Jeffrey
Published: May 2015

The article contains sections titled:

Introduction

Behavior of Gaseous Fission Products for Normal Reactor Conditions

Gaseous Fission Product Behavior

Nucleation and Growth of Intragranular Fission Gas Bubbles

Intergranular Fission Gas: Grain Faces and Edges

Bubble Interlinkage

Intra‐ and Intergranular Bubble Swelling

Fuel Element Swelling

Solid Fission Product Swelling

Fission Gas Swelling at Low Temperature/Low Burnup

Fission Gas Swelling at Low Temperature/High Burnup

Fission Gas Swelling at High Temperature

Fission Gas Release

Grain Size Effects on Gas Release

Validation ofFASTGRASSModel for Fission‐Gas Release

DART: Dispersion Analysis Research Tool

Mechanical Model

Mechanical Model with Aluminide Formation

DART Calculational Algorithms

DART Validation

Cavitational Swelling of α‐Uranium Zone inU–Pu–ZrFuel

Comparison with Data fromU–10ZrandU–19Pu–10ZrFuel Elements

Behavior of Fission Products under Reactor Transient Conditions

Prediction of Fuel Ductility under Transient Heating

Microcracking

Grain Growth/Grain‐Boundary Sweeping

Mobility of Fission Gas Bubbles under Transient Conditions

Fission Gas Release during Transient Conditions

Modeling the Behavior of Volatile Fission Products (VFPs)

VFPChemistry

VFPRelease under Normal Operating Conditions

VFPRelease during Transient Heating

Effect of Fuel Heating Rate onVFPRelease

Effect of Fuel Burnup onVFPRelease

Effect of Fuel Irradiation Temperature onVFPRelease

Effect of Cesium Chemistry onVFPRelease

Fission Gas Behavior in Amorphous Nuclear Fuels

Model of Amorphous Fuel

Bubble Growth at the Knee

Bubble Growth after the Knee‐Point

Comparison with Data

Example of a Calculated Fuel Property

Introduction

Viscosity Model for Binary Alloys Undergoing Amorphization

Looking Forward
Radiation Damage in Metals and Alloys
Authors: Was Gary S.
Published: May 2015

The article contains sections titled:

Introduction

Neutron–Nuclear Interactions

Elastic Collisions

Inelastic Collisions

(n, 2n) Reactions

(n,γ) Reactions

Atomic Displacements

Kinchin‐Pease Model for Atom Displacements

Modifications to the Kinchin–Pease Model

Consideration ofEdandEcin the Energy Balance (Assumptions #3 and #4)

Realistic Energy Transfer Cross‐Sections (Assumption #5)

Effects of Crystallinity (Assumption #6)

Effect of Focusing and Channeling on Displacements

Displacement Cross‐Section and Displacement Rates

Displacement Rates

Damage Cascade

Primary Recoil Spectrum

Cascade Volume and Damage Energy

Stages of Cascade Development

Behavior of Defects within the Cascade

Computer Simulations of Radiation Damage

Radiation‐Enhanced Diffusion

Point Defect Concentrations under Irradiation

Case (i): Low Temperature, Low Sink Density

Case (ii): Low Temperature, Intermediate Sink Density

Case (iii): Low Temperature, High Sink Density

Case (iv): High Temperature

Radiation‐Enhanced Diffusion (RED) Coefficient

Radiation‐Induced Segregation (RIS)

RIS in Concentrated Binary Alloys

Effects of Interstitial Binding, Solute Size, Temperature, and Dose Rate

RIS in Ternary Alloys

Effect of Local Composition Changes on RIS

Effect of Solutes on RIS

RIS in Austenitic Alloys

RIS in Ferritic Alloys

Irradiated Microstructure

Defect Clusters

Cluster Mobility

Loop Nucleation and Clustering Theory

Loop Growth and Recovery

Evolution of Interstitial Loop Microstructure

Void Nucleation and Growth

Bubble Growth

Phase Stability
Copper(I)‐Catalyzed Desulfinative Carboxylation of Sodium Sulfinates using Carbon Dioxide
Authors: Sun Song , Yu Jin‐Tao , Jiang Yan , Cheng Jiang
Published: May 2015

A copper(I)‐catalyzed desulfinative carboxylation of sodium sulfinates using carbon dioxide has been developed. This reaction showed wide functional group tolerance. A series of sodium aryl‐ and alkenylsulfinates could be converted into the corresponding carboxylic acids in good to excellent yields. Additionally, the reaction mechanism was studied by in situ NMR analysis and isotopic labeling experiments.

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Alloimmunization is associated with older age of transfused red blood cells in sickle cell disease
Authors: Desai Payal C. , Deal Allison M. , Pfaff Emily R. , Qaqish Bahjat , Hebden Leyna M. , Park Yara A. , Ataga Kenneth I.
Published: May 2015

Red blood cell (RBC) alloimmunization is a significant clinical complication of sickle cell disease (SCD). It can lead to difficulty with cross‐matching for future transfusions and may sometimes trigger life‐threatening delayed hemolytic transfusion reactions. We conducted a retrospective study to explore the association of clinical complications and age of RBC with alloimmunization in patients with SCD followed at a single institution from 2005 to 2012. One hundred and sixty six patients with a total of 488 RBC transfusions were evaluated. Nineteen patients (11%) developed new alloantibodies following blood transfusions during the period of review. The median age of RBC units was 20 days (interquartile range: 14–27 days). RBC antibody formation was significantly associated with the age of RBC units (P = 0.002), with a hazard ratio of 3.5 (95% CI: 1.71–7.11) for a RBC unit that was 7 days old and 9.8 (95% CI: 2.66–35.97) for a unit that was 35 days old, 28 days after the blood transfusion. No association was observed between RBC alloimmunization and acute vaso‐occlusive complications. Although increased echocardiography‐derived tricuspid regurgitant jet velocity (TRV) was associated with the presence of RBC alloantibodies (P = 0.02), TRV was not significantly associated with alloimmunization when adjusted for patient age and number of transfused RBC units. Our study suggests that RBC antibody formation is significantly associated with older age of RBCs at the time of transfusion. Prospective studies in patients with SCD are required to confirm this finding. Am. J. Hematol. 90:691–695, 2015. © 2015 Wiley Periodicals, Inc.
Surname‐Inferred andean ancestry is associated with child stature and limb lengths at high altitude in Peru, but not at sea level
Authors: Pomeroy Emma , Wells Jonathan C.K. , Stanojevic Sanja , Miranda J. Jaime , Moore Lorna G. , Cole Tim J. , Stock Jay T.
Published: May 2015

Objectives

Native Andean ancestry gives partial protection from reduced birthweight at high altitude in the Andes compared with European ancestry. Whether Andean ancestry is also associated with body proportions and greater postnatal body size at altitude is unknown. Therefore, we tested whether a greater proportion of Andean ancestry is associated with stature and body proportions among Peruvian children at high and low altitude.

Methods

Height, head circumference, head‐trunk height, upper and lower limb lengths, and tibia, ulna, hand and foot lengths, were measured in 133 highland and 169 lowland children aged 6 months to 8.5 years. For highland and lowland groups separately, age‐sex‐adjusted anthropometry z scores were regressed on the number of indigenous parental surnames as a proxy for Andean ancestry, adjusting for potential confounders (maternal age and education, parity, altitude [highlands only]).

Results

Among highland children, greater Andean ancestry was negatively associated with stature and tibia, ulna, and lower limb lengths, independent of negative associations with greater altitude for these measurements. Relationships were strongest for tibia length: each additional Andean surname or 1,000 m increase at altitude among highland children was associated with 0.18 and 0.65 z score decreases in tibia length, respectively. Anthropometry was not significantly associated with ancestry among lowland children.

Conclusions

Greater Andean ancestry is associated with shorter stature and limb measurements at high but not low altitude. Gene‐environment interactions between high altitude and Andean ancestry may exacerbate the trade‐off between chest dimensions and stature that was proposed previously, though we could not test this directly. Am. J. Hum. Biol. 27:798–806, 2015. © 2015 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.
Delineating the spectrum of impairments, disabilities, and rehabilitation needs in methylmalonic acidemia (MMA)
Authors: Ktena Yiouli P. , Paul Scott M. , Hauser Natalie S. , Sloan Jennifer L. , Gropman Andrea , Manoli Irini , Venditti Charles P.
Published: May 2015

Methylmalonic acidemia patients have complex rehabilitation needs that can be targeted to optimize societal independence and quality of life. Thirty‐seven individuals with isolated MMA (28 mut, 5 cblA, 4 cblB), aged 2–33 years, were enrolled in a natural history study, and underwent age‐appropriate clinical assessments to characterize impairments and disabilities. Neurological examination and brain imaging studies were used to document movement disorders and the presence of basal ganglia injury. A range of impairments and disabilities were identified by a team of physical medicine experts. Movement disorders, such as chorea and tremor, were common (n = 31, 83%), even among patients without evidence of basal ganglia injury. Joint hypermobility (n = 24, 69%) and pes planus (n = 22, 60%) were frequent and, in many cases, under‐recognized. 23 (62%) patients required gastrostomy feedings. 18/31 patients >4 years old (58%) had difficulties with bathing and dressing. 16 of 23 school‐aged patients received various forms of educational support. Five of the 10 adult patients were employed or in college; three lived independently. Unmet needs were identified in access to rehabilitation services, such as physical therapy (unavailable to 14/31), and orthotics (unavailable to 15/22). We conclude that patients with MMA are challenged by a number of functional limitations in essential activities of mobility, self‐care, and learning, in great part caused by movement disorders and ligamentous laxity. Early assessment, referral, and implementation of age‐appropriate rehabilitation services should significantly improve independence and quality of life. © 2015 Wiley Periodicals, Inc.
Variable clinical expression in patients with mosaicism for KCNQ2 mutations
Authors: Milh Mathieu , Lacoste Caroline , Cacciagli Pierre , Abidi Affef , Sutera‐Sardo Julie , Tzelepis Ilias , Colin Estelle , Badens Catherine , Afenjar Alexandra , Coeslier Anne Dieux , Dailland Thomas , Lesca Gaetan , Philip Nicole , Villard Laurent
Published: May 2015

Mutations in the KCNQ2 gene, encoding a potassium channel subunit, were reported in patients presenting epileptic phenotypes of varying severity. Patients affected by benign familial neonatal epilepsy (BFNE) are at the milder end of the spectrum, they are affected by early onset epilepsy but their subsequent neurological development is usually normal. Mutations causing BFNE are often inherited from affected parents. Early infantile epileptic encephalopathy type 7 (EIEE7) is at the other end of the severity spectrum and, although EIEE7 patients have early onset epilepsy too, their neurological development is impaired and they will present motor and intellectual deficiency. EIEE7 mutations occur de novo. Electrophysiological experiments suggested a correlation between the type of mutation and the severity of the disease but intra and interfamilial heterogeneity exist. Here, we describe the identification of KCNQ2 mutation carriers who had children affected with a severe epileptic phenotype, and found that these individuals were mosaic for the KCNQ2 mutation. These findings have important consequences for genetic counseling and indicate that neurological development can be normal in the presence of somatic mosaicism for a KCNQ2 mutation. © 2015 Wiley Periodicals, Inc.
Developmental trajectories as autism phenotypes
Authors: Lord Catherine , Bishop Somer , Anderson Deborah
Published: May 2015

Numerous studies of Autism Spectrum Disorder have attempted to link behavioral phenotypes to genetic findings. Reliance on cross‐sectional behavioral data in samples that span wide age ranges may have limited this endeavor because ASD behaviors are not static within individuals across development. This study uses quantitative methods to describe specific aspects of changes in autism‐related and more general behaviors in order to yield trajectories that could be used in place of single time‐point data as behavioral phenotypes in neurobiological studies of both Autism Spectrum Disorders and overlapping conditions. Building on previous analyses, we examined trajectories of parent‐reported social‐communication deficits, social adaptive functioning, and two types of repetitive behaviors, repetitive sensory motor (RSM) behaviors and insistence on sameness (IS) behaviors, in a relatively large sample of participants referred for possible autism at age 2 years and followed into young adulthood (n = 85). A strength of this sample was the diverse range of outcomes, including young adults with intellectual disability and persistent autism related difficulties, those with IQs in the borderline or average range who continued to experience functional impairment related to Autism Spectrum Disorders, and a small group of young adults (n = 8) with IQs in the average range who were judged to be functioning socially and adaptively at age‐appropriate levels at age 19 years, despite a previous childhood diagnosis of autism.