bluuebunny/crossref_metadata_2025 huggingface dataset:
Förderung selbstregulierten Lernens im schulischen Kontext
Authors: Spörer Nadine , Glaser Cornelia
Published: October 2010

Selbstreguliertes Lernen umfasst gedankliche und verhaltensbezogene Aktivitäten, die Lernende dazu befähigen, aufgabenspezifische Fertigkeiten effizient erwerben sowie wirksam und nachhaltig einsetzen zu können. In dem vorliegenden Editorial werden einschlägige Funktions- und Ordnungssysteme selbstregulierten Lernens sowie charakteristische Formen der Vermittlung und Anwendung strategischer Fertigkeiten gekennzeichnet, einschließlich eines Überblicks zu den Beiträgen des Themenschwerpunktes zur «Förderung selbstregulierten Lernens im schulischen Kontext». Als Bestandsaufnahme vorliegender Beiträge werden Grenzen bisheriger und Perspektiven zukünftiger Forschung in diesem Bereich benannt.
Förderung der Schreibkompetenz bei Viertklässlern
Authors: Glaser Cornelia , Keßler Christina , Palm Debora , Brunstein Joachim C.
Published: October 2010

In einer Studie zur Förderung der Schreibkompetenz bei Viertklässlern untersuchten wir spezifische und gemeinsame Effekte prozessorientierter (Überwachung und Korrektur des Strategieeinsatzes) und ergebnisbezogener (Selbstbewertung und Zielsetzung) Prozeduren der Selbstregulation auf Indikatoren der Schreibleistung, Strategiebeherrschung und subjektiven Schreibkompetenz. In sechs Klassen wurden 105 Schüler per Zufall einer von vier Bedingungen in einem 2 (Prozessregulation) × 2 (Ergebnisregulation) Design zugewiesen. Das Training umfasste fünf 90-minütige Sitzungen. Allen Schülern wurden in Kleingruppen Strategien zum erzählenden Schreiben vermittelt. Sowohl zum Posttest als auch zum Follow-up (sechs Wochen später) übertrafen Schüler, die Techniken der Prozessregulation erlernt hatten, Schüler, die keine solche Verfahren eingeübt hatten, im deklarativen und prozeduralen Strategiewissen. Schüler, die Verfahren zur Ergebnisregulation erlernt hatten, schätzten ihre schreibbezogenen Fähigkeiten höher ein als Schüler, die keine derartigen Verfahren erlernt hatten. Die Güte der Schreibleistung und die Einschätzung der schreibbezogenen Selbstwirksamkeit wurden durch beide Faktoren, Prozess- und Ergebnisregulation, positiv beeinflusst.
Schädliche Interferenzen beim Training hochkomplexer Lernstrategien?
Authors: Klauer Karl Josef
Published: October 2010

Bei der Entwicklung von Lernstrategien kann man drei Phasen unterscheiden. In der ersten Phase wurden einzelne Lerntechniken trainiert, die in der zweiten Phase zu sehr komplexen und anspruchsvollen Strategien des selbstregulierten Lernens kombiniert wurden. In der dritten Phase, zu der die vorliegenden Studien gehören, wird es möglich, den Beitrag einzelner Strategiekomponenten zum Effekt der Gesamtstrategie zu analysieren. Prüft man daraufhin die Ergebnisse der Studien, so entsteht der Verdacht, dass möglicherweise einzelne Komponenten miteinander interferiert und auf diese Weise den Gesamteffekt unerwartet geschmälert haben. Das kann auf Überlastung des Arbeitsgedächtnisses zurückzuführen sein, aber auch auf negative Interaktionen der Strategiekomponenten untereinander.
Schereneffekte im ein- und mehrgliedrigen Schulsystem
Authors: Pfost Maximilian , Karing Constance , Lorenz Christian , Artelt Cordula
Published: October 2010

Das deutsche Sekundarschulsystem ist durch seine institutionelle Mehrgliedrigkeit geprägt, welches Schülerinnen und Schülern mit unterschiedlichen Fähigkeiten, aber auch mit unterschiedlicher sozialer Herkunft, differenzielle Entwicklungsbedingungen bietet. So ist davon auszugehen, dass in Schulformen mit höheren Bildungsabschlüssen bessere Lernbedingungen vorherrschen und folglich die Leistungsunterschiede zwischen den Schülerinnen und Schülern der Hauptschulen, Realschulen und Gymnasien im Laufe der Zeit zunehmen. Die Analysen in der vorliegenden Arbeit basieren auf den Daten von N = 922 Schülerinnen und Schülern aus der Bamberger BiKS-Studie (Bildungsprozesse, Kompetenzentwicklung und Formation von Selektionsentscheidungen im Vor- und Grundschulalter). Zunehmende Leistungsunterschiede in der Sekundarstufe zeigen sich für die Lesekompetenz, jedoch nicht für den Wortschatz. Des Weiteren lassen sich zunehmende Leistungsunterschiede der gleichen Schülerinnen und Schüler in der Lesekompetenz bereits in der Grundschule nachweisen, was auf die Bedeutsamkeit der individuellen Eingangsvoraussetzungen zur Erklärung von Schereneffekten hinweist. Darüber hinaus finden sich Belege für den Einfluss institutioneller Faktoren.
Lessons from (triggered) tremor
Authors: Gomberg Joan
Published: October 2010

I test a “clock‐advance” model that implies triggered tremor is ambient tremor that occurs at a sped‐up rate as a result of loading from passing seismic waves. This proposed model predicts that triggering probability is proportional to the product of the ambient tremor rate and a function describing the efficacy of the triggering wave to initiate a tremor event. Using data mostly from Cascadia, I have compared qualitatively a suite of teleseismic waves that did and did not trigger tremor with ambient tremor rates. Many of the observations are consistent with the model if the efficacy of the triggering wave depends on wave amplitude. One triggered tremor observation clearly violates the clock‐advance model. The model prediction that larger triggering waves result in larger triggered tremor signals also appears inconsistent with the measurements. I conclude that the tremor source process is a more complex system than that described by the clock‐advance model predictions tested. Results of this and previous studies also demonstrate that (1) conditions suitable for tremor generation exist in many tectonic environments, but, within each, only occur at particular spots whose locations change with time; (2) any fluid flow must be restricted to less than a meter; (3) the degree to which delayed failure and secondary triggering occurs is likely insignificant; and 4) both shear and dilatational deformations may trigger tremor. Triggered and ambient tremor rates correlate more strongly with stress than stressing rate, suggesting tremor sources result from time‐dependent weakening processes rather than simple Coulomb failure.
On the transient behavior of frictional melt during seismic slip
Authors: Nielsen S. , Mosca P. , Giberti G. , Di Toro G. , Hirose T. , Shimamoto T.
Published: October 2010

In a recent work on the problem of sliding surfaces under the presence of frictional melt (applying in particular to earthquake fault dynamics), we derived from first principles an expression for the steady state friction compatible with experimental observations. Building on the expressions of heat and mass balance obtained in the above study for this particular case of Stefan problem (phase transition with a migrating boundary), we propose here an extension providing a full time‐dependent solution (including the weakening transient after pervasive melting has started, the effect of eventual steps in velocity, and the final decelerating phase). A system of coupled equations is derived and solved numerically. The resulting transient friction and wear evolution yield a satisfactory fit (1) with experiments performed under variable sliding velocities (0.9–2 m s−1) and different normal stresses (0.5–20 MPa) for various rock types and (2) with estimates of slip weakening obtained from observations on ancient seismogenic faults that host pseudotachylite (solidified melt). The model allows us to extrapolate the experimentally observed frictional behavior to large normal stresses representative of the seismogenic Earth crust (up to 200 MPa), high slip rates (up to 9 m s−1), and cases where melt extrusion is negligible. Though weakening distance and peak stress vary widely, the net breakdown energy appears to be essentially independent of either slip velocity or normal stress. In addition, the response to earthquakelike slip can be simulated, showing a rapid friction recovery when slip rate drops. We discuss the properties of energy dissipation, transient duration, velocity weakening, restrengthening in the decelerating final slip phase, and the implications for earthquake source dynamics.
Modeling the impact of declining sea ice on the Arctic marine planktonic ecosystem
Authors: Zhang Jinlun , Spitz Yvette H. , Steele Michael , Ashjian Carin , Campbell Robert , Berline Léo , Matrai Patricia
Published: October 2010

We have developed a coupled 3‐D pan‐Arctic biology/sea ice/ocean model to investigate the impact of declining Arctic sea ice on the marine planktonic ecosystem over 1988–2007. The biophysical model results agree with satellite observations of a generally downward trend in summer sea ice extent during 1988–2007, resulting in an increase in the simulated photosynthetically active radiation (PAR) at the ocean surface and marine primary productivity (PP) in the upper 100 m over open water areas of the Arctic Ocean. The simulated Arctic sea ice thickness has decreased steadily during 1988–2007, leading to an increase in PAR and PP in sea ice‐covered areas. The simulated total PAR in all areas of the Arctic Ocean has increased by 43%, from 146 TW in 1988 to 209 TW in 2007; the corresponding total PP has increased by 50%, from 456 Tg C yr−1 in 1988 to 682 Tg C yr−1 in 2007. The simulated PAR and PP increases mainly occur in the seasonally and permanently ice‐covered Arctic Ocean. In addition to increasing PAR, the decline in sea ice tends to increase the nutrient availability in the euphotic zone by enhancing air‐sea momentum transfer, leading to strengthened upwelling and mixing in the water column and therefore increased nutrient input into the upper ocean layers from below. The increasing nutrient availability also contributes to the increase in the simulated PP, even though significant surface nutrient drawdown in summer is simulated. In conjunction with increasing surface absorption of solar radiation and rising surface air temperature, the increasing surface water temperature in the Arctic Ocean peripheral seas further contributes to the increase in PP. As PP has increased, so has the simulated biomass of phytoplankton and zooplankton.
Changes in net ecosystem productivity and greenhouse gas exchange with fertilization of Douglas fir: Mathematical modeling in ecosys
Authors: Grant R. F. , Black T. A. , Jassal R. S. , Bruemmer C.
Published: October 2010

The application of nitrogen fertilizers to Douglas fir forests is known to raise net ecosystem productivity (NEP), but also N2O emissions, the CO2 equivalent of which may offset gains in NEP when accounting for net greenhouse gas (GHG) exchange. However, total changes in NEP and N2O emissions caused by fertilizer between times of application and harvest, while needed for national GHG inventories, are difficult to quantify except through modeling. In this study, integrated hypotheses for soil and plant N processes within the ecosystem model ecosys were tested against changes in CO2 and N2O fluxes recorded with eddy covariance (EC) and surface flux chambers for 1 year after applying 20 g N m−2 of urea to a mature Douglas fir stand in British Columbia. Parameters from annual regressions of hourly modeled versus measured CO2 fluxes conducted before and after fertilization were unchanged (b = 1.0, R2 = 0.8, RMSD = 3.4 μmol m−2 s−1), indicating that model hypotheses for soil and plant N processes did not introduce bias into CO2 fluxes modeled after fertilization. These model hypotheses were then used to project changes in NEP and GHG exchange attributed to the fertilizer during the following 10 years until likely harvest of the Douglas fir stand. Increased CO2 uptake caused modeled and EC‐derived annual NEP to rise from 443 and 386 g C m−2 in the year before fertilization to 591 and 547 g C m−2 in the year after. These gains contributed to a sustained rise in modeled wood C production with fertilization, which was partly offset by a decline in soil C attributed in the model to reduced root C productivity and litterfall. Gains in net CO2 uptake were further offset in the model by a rise of 0.74 g N m−2 yr−1 in N2O emissions during the first year after fertilization, which was consistent with one of 1.05 g N m−2 yr−1 estimated from surface flux chamber measurements. Further N2O emissions were neither modeled nor measured after the first year. At the end of the 11 year model projection, a total C sequestration of 1045 g C m−2 was attributed to the 20 g N m−2 of fertilizer. However, only 119 g C m−2 of this was sequestered in stocks that would remain on site after harvest (foliage, root, litter, soil). The remainder was sequestered as harvested wood, the duration of which would depend on use of the wood product. The direct and indirect CO2‐equivalent costs of this application, including N2O emission, were estimated to offset almost all non‐harvested C sequestration attributed to the fertilizer.
Rill erosion in natural and disturbed forests: 1. Measurements
Authors: Robichaud P. R. , Wagenbrenner J. W. , Brown R. E.
Published: October 2010

Rill erosion can be a large portion of the total erosion in disturbed forests, but measurements of the runoff and erosion at the rill scale are uncommon. Simulated rill erosion experiments were conducted in two forested areas in the northwestern United States on slopes ranging from 18 to 79%. We compared runoff rates, runoff velocities, and sediment flux rates from natural (undisturbed) forests and in forests either burned at low soil burn severity (10 months or 2 weeks post‐fire), high soil burn severity, or subject to skidding of felled logs. The runoff rates and velocities in the natural sites (2.7 L min−1 and 0.016 m s−1, respectively) were lower than those in all the disturbed sites (12 to 21 L min−1 and 0.19 to 0.31 m s−1, respectively), except for the 10‐month old low soil burn severity site where the velocity (0.073 m s−1) was indistinguishable from the natural sites. The mean sediment flux rate in the natural sites also was very small (1.3 × 10−5 kg s−1) as compared to the rates in the disturbed areas (2.5 × 10−4 to 0.011 kg s−1). The hillslope gradient did not affect the runoff or sediment responses. The sediment flux rates generally were greater in the initial stage of each inflow period than in the steady state condition, but there was no corresponding transient effect in runoff rates. Rill erosion modeling implications based on these data are presented in part 2 of this study.
Rill erosion in natural and disturbed forests: 2. Modeling Approaches
Authors: Wagenbrenner J. W. , Robichaud P. R. , Elliot W. J.
Published: October 2010

As forest management scenarios become more complex, the ability to more accurately predict erosion from those scenarios becomes more important. In this second part of a two‐part study we report model parameters based on 66 simulated runoff experiments in two disturbed forests in the northwestern U.S. The 5 disturbance classes were natural, 10‐month old and 2‐week old low soil burn severity, high soil burn severity, and logging skid trails. In these environments the erosion rates were clearly detachment limited, and the rill erodibility parameters calculated from four hydraulic variables increased by orders of magnitude. The soil shear stress based erodibility parameter, Kr, was 1.5 × 10−6 s m−1in the natural plots, 2.0 × 10−4 s m−1 in the high soil burn severity plots, and 1.7 × 10−3 s m−1 in the skid trail plots; Kr values for the low soil burn severity plots had negative sign. The erodibility value for the skid trail plots fell within ranges reported for tilled agricultural fields and also for forest roads. The Kr values decreased as erosion occurred in the plots and therefore should not be a constant parameter. The stream power produced the largest R2 value (0.41) when hydraulic predictors and the sediment flux were log‐transformed, but none of the four hydraulic variables (soil shear stress, stream power, unit stream power, and unit length shear force) explained much of the variability in sediment flux rates across the five levels of disturbance when evaluated in the linear form of the erosion models under consideration.
Ancient numerical daemons of conceptual hydrological modeling: 1. Fidelity and efficiency of time stepping schemes
Authors: Clark Martyn P. , Kavetski Dmitri
Published: October 2010

A major neglected weakness of many current hydrological models is the numerical method used to solve the governing model equations. This paper thoroughly evaluates several classes of time stepping schemes in terms of numerical reliability and computational efficiency in the context of conceptual hydrological modeling. Numerical experiments are carried out using 8 distinct time stepping algorithms and 6 different conceptual rainfall‐runoff models, applied in a densely gauged experimental catchment, as well as in 12 basins with diverse physical and hydroclimatic characteristics. Results show that, over vast regions of the parameter space, the numerical errors of fixed‐step explicit schemes commonly used in hydrology routinely dwarf the structural errors of the model conceptualization. This substantially degrades model predictions, but also, disturbingly, generates fortuitously adequate performance for parameter sets where numerical errors compensate for model structural errors. Simply running fixed‐step explicit schemes with shorter time steps provides a poor balance between accuracy and efficiency: in some cases daily‐step adaptive explicit schemes with moderate error tolerances achieved comparable or higher accuracy than 15 min fixed‐step explicit approximations but were nearly 10 times more efficient. From the range of simple time stepping schemes investigated in this work, the fixed‐step implicit Euler method and the adaptive explicit Heun method emerge as good practical choices for the majority of simulation scenarios. In combination with the companion paper, where impacts on model analysis, interpretation, and prediction are assessed, this two‐part study vividly highlights the impact of numerical errors on critical performance aspects of conceptual hydrological models and provides practical guidelines for robust numerical implementation.
Experimental and analytic modeling of piercement structures
Authors: Nermoen A. , Galland O. , Jettestuen E. , Fristad K. , Podladchikov Y. , Svensen H. , Malthe‐Sørenssen A.
Published: October 2010

Piercement structures such as mud volcanoes, hydrothermal vent complexes, pockmarks and kimberlite pipes, form during the release of pressurized fluids. The goal of this work is to predict under which conditions piercement structures form from the insights gained by sand box experiments injecting compressed air through an inlet of width w at the base of a bed of glass beads of height h. At an imposed critical velocity vf, a fluidized zone consisting of a diverging cone‐like structure formed with morphological similarities to those observed in nature. Dimensional analysis showed that vf is correlated to the ratio of h over w. In addition, we derived an analytical model for vf which is compared to the experimental data. The model consists of a force balance between the weight and the seepage forces imparted to the bed by the flowing gas. The analytic model reproduces the observed correlation between vf and h/w, although a slight underestimate was obtained. The results suggest that the gas‐particle seepage force is the main triggering factor for fluidization and that the commonly used proxy, which the fluid pressure must equal or exceed the lithostatic weight, needs to be reconsidered. By combining the experiments and the model, we derived critical pressure estimates which were employed to a variety of geological environments. Comparing the estimated and measured pressures prior to the Lusi mud volcano shows that the presented model overestimates the critical pressures. The model paves the way for further investigations of the critical conditions for fluidization in Earth systems.
Oyster larval transport in coastal Alabama: Dominance of physical transport over biological behavior in a shallow estuary
Authors: Kim Choong‐Ki , Park Kyeong , Powers Sean P. , Graham William M. , Bayha Keith M.
Published: October 2010

Among the various factors affecting recruitment of marine invertebrates and fish, larval transport may produce spatial and temporal patterns of abundance that are important determinants of management strategies. Here we conducted a field and modeling study to investigate the larval transport of eastern oyster, Crassostrea virginica, in Mobile Bay and eastern Mississippi Sound, Alabama. A three‐dimensional larval transport model accounting for physical transport, biological movement of larvae, and site‐ and larval‐specific conditions was developed. A hydrodynamic model was used to simulate physical transport, and biological movement was parameterized as a function of swimming and sinking velocity of oyster larvae. Site‐ and larval‐specific conditions, including spawning location, spawning stock size, spawning time, and larval period, were determined based on the previous studies. The model reasonably reproduced the observed gradient in oyster spat settlement and bivalve larval concentration, although the model results were less dynamic than the data, probably owing to the simplified biological conditions employed in the model. A persistent gradient decreasing from west to east in the model results at time scales of overall average, season, and each survey in 2006 suggests that the larval supply may be responsible for the corresponding gradient in oyster spat settlement observed over the past 40 years. Biological movement increased larval retention near the spawning area, thus providing a favorable condition for local recruitment of oysters. Inclusion of biological movement, however, caused little change in the overall patterns of larval transport and still resulted in a west‐east gradient, presumably because of frequent destratification in the shallow Mobile Bay system.
Formation of tidal sand waves: Effects of the spring‐neap cycle
Authors: Blondeaux Paolo , Vittori Giovanna
Published: October 2010

The effects that the spring‐neap cycle has on the formation of tidal sand waves are investigated by performing a linear stability analysis of the flat bottom configuration of a shallow sea subject to a modulated tidal current. The slow temporal changes of the tidal range tend to accelerate the process which leads to the appearance of tidal sand waves and to give rise to shorter bed forms, when sediment transport is dominated by the bed load contribution. When the suspended load provides a significant contribution to the total load, the growth rate of the sand waves becomes smaller and longer bed forms tend to be generated.
An enormous amorphous silica stock in boreal wetlands
Authors: Struyf Eric , Mörth Carl‐Magnus , Humborg Christoph , Conley Daniel J.
Published: October 2010

We investigated amorphous Si (ASi) in a boreal wetland in northern Sweden. We found enormous stocks of ASi in the upper soil layers (up to 11% of dry weight), in the form of diatom frustules and plant ASi. A consistent exponential decrease in ASi concentrations was observed with increasing depth in the soil profile. An inverse modeling approach shows that vegetation takes up a substantial part of weathered dissolved Si (DSi). Concurrent analysis of N and C indicates a faster turnover in and a higher leakage from the ASi pool. The magnitude of the biological buffering we observed is unprecedented and supports the emerging paradigm of the importance of biological uptake of DSi governing the export of DSi from terrestrial ecosystems. Our results complicate current models of silicate transport, highlighting the necessity to incorporate ecosystem biological buffering in our concept of Si biogeochemistry.
Overexpression of Constitutively Active PKG‐I Protects Female, But Not Male Mice From Diet‐Induced Obesity
Authors: Nikolic Dejan M. , Li Yanzhang , Liu Shu , Wang Shuxia
Published: October 2010

Cyclic guanosine monophosphate (cGMP)–dependent protein kinase I (PKG‐I) is a multifunctional protein. The direct effects of PKG‐I activation on energy homeostasis and obesity development are not well understood. Herein, we generated transgenic mice with expression of the constitutively active PKG‐I in adipose tissue as well as in other tissues. Male and female PKG‐I overexpressing mice were fed a low‐fat (LF) or high‐fat (HF) diet for 16 weeks. HF‐fed female PKG‐I transgenic mice had decreased body weight gain, lower percentage of body fat, and improved glucose tolerance compared to HF‐fed wild‐type (WT) controls. In contrast, male transgenic PKG‐I mice were not resistant to the development of HF‐diet‐induced obesity, and exhibited similar levels of adiposity and glucose intolerance as HF‐fed WT controls. Furthermore, we found that HF‐fed female transgenic PKG‐I mice had increased energy expenditure and cold‐induced adaptive thermogenesis compared to HF‐fed WT controls, which was associated with increased expression of uncoupling protein‐1 (UCP1) in brown adipose tissue (BAT). In addition, the rates of lipolysis in white adipose tissue (WAT) were also increased in female transgenic PKG‐I mice compared to WT controls due to increased phosphorylation of hormone‐sensitive lipase (HSL). However, in male mice, adaptive thermogenesis or WAT lipolysis was similar between transgenic PKG‐I mice and WT controls. Together, these data demonstrate sex differences in effects of PKG‐I activation on the regulation of adipose tissue function and its contribution to diet induced obesity.
Identifying Patterns of Eating and Physical Activity in Children: A Latent Class Analysis of Obesity Risk
Authors: Huh Jimi , Riggs Nathaniel R. , Spruijt‐Metz Donna , Chou Chih‐Ping , Huang Zhaoqing , Pentz MaryAnn
Published: October 2010

We used latent class analysis (LCA) to identify heterogeneous subgroups with respect to behavioral obesity risk factors in a sample of 4th grade children (n = 997) residing in Southern California. Multiple dimensions assessing physical activity, eating and sedentary behavior, and weight perceptions were explored. A set of 11 latent class indicators were used in the analysis. The final model yielded a five‐class solution: “High‐sedentary, high‐fat/high‐sugar (HF/HS) snacks, not weight conscious,” “dieting without exercise, weight conscious,” “high‐sedentary, HF/HS snacks, weight conscious,” “active, healthy eating,” and “low healthy, snack food, inactive, not weight conscious.” The results suggested distinct subtypes of children with respect to obesity‐related risk behaviors. Ethnicity, gender, and a socioeconomic status proxy variable significantly predicted the above latent classes. Overweight or obese weight status was determined based on the Centers for Disease Control and Prevention BMI (kg/m2)‐for‐age‐and‐sex percentile (overweight, 85th percentile ≤BMI <95th percentile; obese, 95th percentile ≤BMI). The identified latent subgroup membership, in turn, was associated with the children's weight categories. The results suggest that intervention programs could be refined or targeted based on children's characteristics to promote effective pediatric obesity interventions.
Associations of SNPs in ADIPOQ and Subclinical Cardiovascular Disease in the Multi‐Ethnic Study of Atherosclerosis (MESA)
Authors: Wassel Christina L. , Pankow James S. , Rasmussen‐Torvik Laura J. , Li Na , Taylor Kent D. , Guo Xiuqing , Goodarzi Mark O. , Palmas Walter R. , Post Wendy S.
Published: October 2010

Circulating adiponectin is associated with both clinical and subclinical cardiovascular disease (CVD). Variants of the adiponectin gene (ADIPOQ) are associated with clinical CVD, but little is known about associations with subclinical CVD. We studied the association of 11 ADIPOQ single‐nucleotide polymorphisms (SNPs) with common and internal carotid intima media thickness (cIMT), presence of coronary artery calcification (CAC), and CAC scores (in those with CAC) in 2,847 participants in the Multi‐Ethnic Study of Atherosclerosis (MESA). Participants were white (n = 712), African American (n = 712), Chinese (n = 718), and Hispanic (n = 705). All models were adjusted for age, sex, and field site, and stratified by race/ethnic group. African Americans with genotypes AG/GG of rs2241767 had 36% greater (95% confidence interval (CI; 16%, 59%), P = 0.0001) CAC prevalence; they also had a larger common cIMT (P = 0.0043). Also in African Americans, genotypes AG/AA of rs1063537 were associated with a 35% (95% CI (14%, 59%), P = 0.0005) greater CAC prevalence. Hispanics with the AA genotype of rs11711353 had a 37% (95% CI (14%, 66%), P = 0.0011), greater CAC prevalence compared to those with the GG genotype. Additional adjustment for ancestry in African‐American and Hispanic participants did not change the results. No single SNP was associated with subclinical CVD phenotypes in Chinese or white participants. There appears to be an association between ADIPOQ SNPs and subclinical CVD in African Americans and Hispanics. Replication as well as assessment of other ADIPOQ SNPs is warranted.
Using Standardized Tests to Inventory Consonant and Vowel Production: A Comparison of 11 Tests of Articulation and Phonology
Authors: Eisenberg Sarita L. , Hitchcock Elaine R.
Published: October 2010

Purpose

This report considered the validity of making conclusions about a child’s phonetic inventory (the sounds a child can and cannot produce spontaneously without a prior model or other stimulation) based on the data from standardized single-word tests of articulation or phonology.

Method

We evaluated the opportunities for production of word-initial consonants, word-final consonants, and vowels within the words included on 11 tests. Only words that met specific phonetic criteria (termed phonetically controlled words) were counted as opportunities for each consonant or vowel.

Results

None of the tests provided sufficient coverage of consonants or vowels for establishing a phonetic inventory and making conclusions about the segments that a child can and cannot produce.

Conclusion

Use of the data from a single standardized test of articulation or phonology would not be sufficient for completely inventorying a child’s consonant and vowel production and selecting targets for therapy. It is recommended that clinicians supplement test data by probing production in additional phonetically controlled words.
An Issue Hiding in Plain Sight: When Are Speech-Language Pathologists Special Educators Rather Than Related Services Providers?
Authors: Giangreco Michael F. , Prelock Patricia A. , Turnbull H. Rutherford
Published: October 2010

Purpose

Under the Individuals With Disabilities Education Act (IDEA; as amended, 2004), speech-language pathology services may be either special education or a related service. Given the absence of guidance documents or research on this issue, the purposes of this clinical exchange are to (a) present and analyze the IDEA definitions related to speech-language pathologists (SLPs) and their roles, (b) offer a rationale for the importance of and distinction between their roles, (c) propose an initial conceptualization (i.e., flow chart) to distinguish between when an SLP should function as a related services provider versus a special educator, and (d) suggest actions to develop and disseminate a clearer shared understanding of this issue.

Method

Federal definitions of special education and related services as related to SLPs are discussed in terms of determining special education eligibility, meeting student needs, ensuring SLPs are following their code of ethics and scope of practice, and facilitating appropriate personnel utilization and service delivery planning.

Conclusion

Clarifying the distinction between special education and related services should lead to increased likelihood of appropriate services for students with disabilities, improved working conditions for SLPs, and enhanced collaboration among team members. This clinical exchange is meant to promote dialogue and research about this underexamined issue.
Current Training and Continuing Education Needs of Preschool and School-Based Speech-Language Pathologists Regarding Children With Cleft Lip/Palate
Authors: Bedwinek Anne P. , Kummer Ann W. , Rice Gale B. , Grames Lynn Marty
Published: October 2010

Purpose

The purpose of this study was to obtain information regarding the education and experience of preschool and school-based speech-language pathologists (SLPs) regarding the assessment and treatment of children born with cleft lip and/or palate and to determine their continuing education needs in this area.

Method

A 16-item mixed-methods survey to collect quantitative and qualitative data was distributed via postal mail to a geographically diverse random sample of 565 preschool and school SLPs.

Results

The response rate was 59%. With an average of 15.93 years in practice, respondents reported that they infrequently saw children with cleft lip/palate. When treating these children, respondents wanted communication with the cleft–craniofacial team, accessible continuing education through Web sites and conferences, and clinically practical information relevant to the school setting.

Conclusion

When assessing and treating a low-incidence population such as children with cleft-related communication disorders, school-based SLPs need accessible, accurate continuing education resources and collaboration with specialists in the field.
Language Sampling: Does the Length of the Transcript Matter?
Authors: Heilmann John , Nockerts Ann , Miller Jon F.
Published: October 2010

Purpose

Language sample analysis is considered by many to be the gold standard for documenting children’s oral language skills. One limitation, however, is the time required for collection and transcription of language samples. The goal of this study was to determine if stable language sample measures could be generated using relatively short language samples.

Method

Measures were generated from children’s conversational and narrative language samples after they were broken into three lengths (1-, 3-, and 7-min samples). The measures were compared to determine the stability of measures from the short samples (1 and 3 min) when compared to measures from the long sample (7 min). The measures were further analyzed to determine if differences across transcript cuts varied as a function of age group (2;8 [years;months]–5;11 vs. 6;0–13;3) or sampling context (conversation vs. narrative).

Results

Overall, the language sample measures were quite consistent across the transcript cuts. Measures of productivity, lexical diversity, and utterance length were the most reliable when short samples were used.

Conclusion

Implications for the efficient use of language sample analysis in clinical protocols are discussed. A framework for eliciting reliable short samples is provided.
Quality of Communication Life in Adolescents With High-Functioning Autism and Asperger Syndrome: A Feasibility Study
Authors: Burgess Sloane , Turkstra Lyn S.
Published: October 2010

Purpose

This study was designed to evaluate the feasibility of using the American Speech-Language-Hearing Association’s Quality of Communication Life Scale (QCL; Paul et al., 2004) for a group of individuals with developmental communication disorders—adolescents with high-functioning autism/Asperger syndrome (HFA/AS). Perceptions of quality of communication life (QoCL) have not been studied in this group and are important for intervention planning.

Method

Fourteen adolescents with HFA/AS and 15 typically developing peers rated their QoCL using the QCL. Mothers of study participants also rated their children’s QoCL. It was hypothesized that the adolescents with HFA/AS would rate their QoCL less positively than their peers and more positively than their mothers.

Results

The QoCL ratings of adolescents with HFA/AS were significantly lower than those of their peers but were generally positive. Self-ratings for the HFA/AS group were somewhat higher than parent ratings.

Conclusion

The results of this study provide evidence that adolescents with HFA/AS can effectively evaluate aspects of their QoCL and that the QCL may provide useful information for this group. The study also provides preliminary evidence that adolescents with HFA/AS rate their QoCL lower than their peers. Further research is necessary to better understand the meaning of lower ratings for this group and the effects of intervention on their perceptions of their QoCL.
Who Does What to Whom: Introduction of Referents in Children’s Storytelling From Pictures
Authors: Schneider Phyllis , Hayward Denyse
Published: October 2010

Purpose

This article describes the development of a measure, called First Mentions (FM), that can be used to evaluate the referring expressions that children use to introduce characters and objects when telling a story.

Method

Participants were 377 children ages 4 to 9 years (300 with typical development, 77 with language impairment) who told stories while viewing 6 picture sets. Their first mentions of 8 characters and 6 objects were scored as fully adequate, partially adequate, inadequate, or not mentioned. Total FM scores were compared across age and language groups.

Results

There were significant differences for age and language status, as well as a significant Age × Language interaction. Within each age group except age 9, children in the typical development group attained higher scores than children in the group with language impairment.

Conclusion

These results suggest that the FM measure is a useful tool for identifying whether a child has a problem with introducing referents in stories.
Performance study of high operating temperature HgCdTe mid wave infrared detector through numerical modeling
Authors: Srivastav Vanya , Pal R. , Venkataraman V.
Published: October 2010

The design of present generation uncooled Hg1−xCdxTe infrared photon detectors relies on complex heterostructures with a basic unit cell of type ṉ+/π/p̱+. We present an analysis of double barrier ṉ+/π/p̱+ mid wave infrared (x=0.3) HgCdTe detector for near room temperature operation using numerical computations. The present work proposes an accurate and generalized methodology in terms of the device design, material properties, and operation temperature to study the effects of position dependence of carrier concentration, electrostatic potential, and generation-recombination (g-r) rates on detector performance. Position dependent profiles of electrostatic potential, carrier concentration, and g-r rates were simulated numerically. Performance of detector was studied as function of doping concentration of absorber and contact layers, width of both layers and minority carrier lifetime. Responsivity ∼0.38 A W−1, noise current ∼6×10−14 A/Hz1/2 and D∗ ∼3.1×1010cm Hz1/2 W−1 at 0.1 V reverse bias have been calculated using optimized values of doping concentration, absorber width and carrier lifetime. The suitability of the method has been illustrated by demonstrating the feasibility of achieving the optimum device performance by carefully selecting the device design and other parameters.
Experimental study of neutron induced background noise on gated x-ray framing cameras
Authors: Izumi N. , Hagmann C. , Stone G. , Hey D. , Glenn S. , Conder A. , Teruya A. , Sorce C. , Tommasini R. , Stoeffl W. , Springer P. , Landen O. L. , Herrmann H. W. , Kyrala G. A. , Bahukutumbi R. , Glebov V. Y. , Sangster T. C. , Eckart M. , Mackinnon A. J. , Koch J. A. , Bradley D. K. , Bell P.
Published: October 2010

A temporally gated x-ray framing camera based on a proximity focus microchannel plate is one of the most important diagnostic tools of inertial confinement fusion experiments. However, fusion neutrons produced in imploded capsules interact with structures surrounding the camera and produce background to x-ray signals. To understand the mechanisms of this neutron induced background, we tested several gated x-ray cameras in the presence of 14 MeV neutrons produced at the Omega laser facility. Differences between background levels observed with photographic film readout and charge-coupled-device readout have been studied.
Interpretation and implementation of an ion sensitive probe as a plasma potential diagnostic
Authors: Ochoukov R. , Whyte D. G. , Lipschultz B. , LaBombard B. , Wukitch S.
Published: October 2010

An ion sensitive probe (ISP) is developed as a robust diagnostic for measuring plasma potentials (ΦP) in magnetized plasmas. The ISP relies on the large difference between the ion and electron gyroradii (ρi/ρe∼60) to reduce the electron collection at a collector recessed behind a separately biased wall distance ∼ρi. We develop a new ISP method to measure the plasma potential that is independent of the precise position and shape of the collector. ΦP is found as the wall potential when charged current to the probe collector vanishes during the voltage sweep. The plasma potentials obtained from the ISP match ΦP measured with an emissive probe over a wide range of plasma conditions in a small magnetized plasma.
Light emission from silicon/gold nanoparticle systems
Authors: Bassu M. , Strambini M. L. , Barillaro G. , Fuso F.
Published: October 2010

Photoluminescent nanostructured semiconductor/metal systems consisting of silicon nanocrystals and gold nanoparticles are obtained by gold-catalyzed chemical etching. The interplay between silicon and gold nanostructures is investigated by photoluminescence spectroscopy upon continuous and pulsed excitation, both at room and low temperature. Comparison with reference samples, obtained removing gold particles by selective etching, highlights an enhanced emission in samples containing silicon and gold nanoparticles, explained in terms of both surface modifications and optical coupling between emitting nanocrystals and nanoparticles featuring localized plasmon resonances.
Role of dispersion on phononic thermal boundary conductance
Authors: Duda John C. , Beechem Thomas E. , Smoyer Justin L. , Norris Pamela M. , Hopkins Patrick E.
Published: October 2010

The diffuse mismatch model (DMM) is one of the most widely implemented models for predicting thermal boundary conductance at interfaces where phonons dominate interfacial thermal transport. In the original presentation of the DMM, the materials comprising the interface were described as Debye solids. Such a treatment, while accurate in the low temperature regime for which the model was originally intended, is less accurate at higher temperatures. Here, the DMM is reformulated such that, in place of Debye dispersion, the materials on either side of the interface are described by an isotropic dispersion obtained from exact phonon dispersion diagrams in the [100] crystallographic direction. This reformulated model is applied to three interfaces of interest: Cr–Si, Cu–Ge, and Ge–Si. It is found that Debye dispersion leads to substantially higher predictions of thermal boundary conductance. Additionally, it is shown that optical phonons play a significant role in interfacial thermal transport, a notion not previously explored. Lastly, the role of the assumed dispersion is more broadly explored for Cu–Ge interfaces. The prediction of thermal boundary conductance via the DMM with the assumed isotropic [100] dispersion relationships is compared to predictions with isotropic [111] and exact three-dimensional phonon dispersion relationships. It is found that regardless of the chosen crystallographic direction, the predictions of thermal boundary conductance using isotropic phonon dispersion relationships are within a factor of two of those predictions using an exact three-dimensional phonon dispersion.
Optical forces on arbitrary shaped particles in optical tweezers
Authors: Ling Lin , Zhou Fei , Huang Lu , Li Zhi-Yuan
Published: October 2010

Discrete dipole approximation (DDA) method is an efficient method for computing electromagnetic (EM) field of nanometer/micrometer-sized dielectric particles with arbitrary geometric shape and topology. In this work we employ the DDA method to calculate the optical force of dielectric shaped particles embedded in optical tweezers made from focused Gaussian laser beams. The EM force is calculated based on the self-consistent solution of EM field distribution and discrete dipole moment distribution within the particles. The DDA method agrees well with the Mie theory for spherical dielectric particles and this supports the effectiveness of the DDA method in handling optical forces in optical tweezers. The optical force for shaped particles such as cubes, rectangles, cylinders, and core-shell composite particles shows many interesting features. The force strongly depends on the orientation of the particle with respect to the laser beam propagation and polarization direction and the aspect ratio of the anisotropic particle. For a core-shell composite particle the zero-force balance point shifts from the particle center to its two sides. When an additional particle comes close a trapped particle, the perturbation effect strongly depends on the relative location of the center of the focused laser beam with respect to the two particles. Furthermore, the geometry of shaped particles not only affects the magnitude of the optical force but also influences the optical trap stiffness.
Magnetic confinement of Brownian rotation to a single axis and application to Janus and cluster microparticles
Authors: McNaughton Brandon H. , Shlomi Miri , Kinnunen Paivo , Cionca Codrin , Pei Shao Ning , Clarke Roy , Argyrakis Panos , Kopelman Raoul
Published: October 2010

We present an experimental, one-dimensional, Brownian rotation system in which the free rotation is confined to a single axis. Control of the rotational diffusion of a single microparticle, or particle aggregate, around a chosen axis, was performed by using a static 1.0 mT external magnetic field. The confined object rotated freely around the chosen axis, and that axis was confined to within 3.9°. This method presents several advantages and may have wide applicability in biological and physical systems of interest.
Dislocation reduction via selective-area growth of InN accompanied by lateral growth by rf-plasma-assisted molecular-beam epitaxy
Authors: Kamimura Jumpei , Kishino Katsumi , Kikuchi Akihiko
Published: October 2010

We investigated the selective-area growth (SAG) of InN by rf-plasma-assisted molecular-beam epitaxy using molybdenum (Mo)-mask-patterned sapphire (0001) substrates, which resulted in the formation of regularly arranged N-polar InN microcrystals. Transmission electron microscopy observation confirmed that the laterally grown side areas were nearly dislocation-free, although many threading dislocations (109–1010 cm−2) were generated at the InN/sapphire interface and propagated into the center of the InN microcrystals along the crystal c-axis. The laterally grown InN microcrystals exhibited narrow near-IR emission spectra with a peak photon energy of 0.627 eV and a linewidth of 39 meV at room temperature.