bluuebunny/crossref_metadata_2025 huggingface dataset:
Prosodic Structure Shapes the Temporal Realization of Intonation and Manual Gesture Movements
Authors: Esteve-Gibert Núria , Prieto Pilar
Published: December 2012

Purpose

Previous work on the temporal coordination between gesture and speech found that the prominence in gesture coordinates with speech prominence. In this study, the authors investigated the anchoring regions in speech and pointing gesture that align with each other. The authors hypothesized that (a) in contrastive focus conditions, the gesture apex is anchored in the intonation peak and (b) the upcoming prosodic boundary influences the timing of gesture and intonation movements.

Method

Fifteen Catalan speakers pointed at a screen while pronouncing a target word with different metrical patterns in a contrastive focus condition and followed by a phrase boundary. A total of 702 co-speech deictic gestures were acoustically and gesturally analyzed.

Results

Intonation peaks and gesture apexes showed parallel behavior with respect to their position within the accented syllable: They occurred at the end of the accented syllable in non–phrase-final position, whereas they occurred well before the end of the accented syllable in phrase-final position. Crucially, the position of intonation peaks and gesture apexes was correlated and was bound by prosodic structure.

Conclusions

The results refine the phonological synchronization rule (McNeill, 1992), showing that gesture apexes are anchored in intonation peaks and that gesture and prosodic movements are bound by prosodic phrasing.
Discriminating Children With Language Impairment Among English-Language Learners From Diverse First-Language Backgrounds
Authors: Paradis Johanne , Schneider Phyllis , Duncan Tamara Sorenson
Published: December 2012

Purpose

In this study, the authors sought to determine whether a combination of English-language measures and a parent questionnaire on first-language development could adequately discriminate between English-language learners (ELLs) with and without language impairment (LI) when children had diverse first-language backgrounds.

Method

Participants were 152 typically developing (TD) children and 26 children with LI; groups were matched for age (
M
=5;10 [years;months]) and exposure to English (
M
=21 months). Children were given English standardized tests of nonword repetition, tense morphology, narrative story grammar, and receptive vocabulary. Parents were given a questionnaire on children's first-language development.

Results

ELLs with LI had significantly lower scores than the TD ELLs on the first-language questionnaire and all the English-language measures except for vocabulary. Linear discriminant function analyses showed that good discrimination between the TD and LI groups could be achieved with all measures, except vocabulary, combined. The strongest discriminator was the questionnaire, followed by nonword repetition and tense morphology.

Conclusion

Discrimination of children with LI among a diverse group of ELLs might be possible when using a combination of measures. Children with LI exhibit deficits in similar linguistic/cognitive domains regardless of whether English is their first or second language.
Effects of a Naturalistic Sign Intervention on Expressive Language of Toddlers With Down Syndrome
Authors: Wright Courtney A. , Kaiser Ann P. , Reikowsky Dawn I. , Roberts Megan Y.
Published: December 2012

Purpose

In this study, the authors evaluated the effects of Enhanced Milieu Teaching (EMT; Hancock & Kaiser, 2006) blended with Joint Attention, Symbolic Play, and Emotional Regulation (JASPER; Kasari, Freeman, & Paparella, 2006) to teach spoken words and manual signs (Words + Signs) to young children with Down syndrome (DS).

Method

Four toddlers (ages 23–29 months) with DS were enrolled in a study with a multiple-baseline, across-participants design. Following baseline, 20 play-based treatment sessions (20–30 min each) occurred twice weekly. Spoken words and manual signs were modeled and prompted by a therapist who used EMT/JASPER teaching strategies. The authors assessed generalization to interactions with parents at home.

Results

There was a functional relation between the therapist's implementation of EMT/JASPER Words + Signs and all 4 children's use of signs during the intervention. Gradual increases in children's use of spoken words occurred, but there was not a clear functional relation. All children generalized their use of signs to their parents at home.

Conclusions

The infusion of manual signs with verbal models within a framework of play, joint attention, and naturalistic language teaching appears to facilitate development of expressive sign and word communication in young children with DS.
Is More Better? Milieu Communication Teaching in Toddlers With Intellectual Disabilities
Authors: Fey Marc E. , Yoder Paul J. , Warren Steven F. , Bredin-Oja Shelley L.
Published: December 2012

Purpose

The authors sought to determine whether a program of 5 weekly doses of milieu communication teaching (MCT) would yield improvements in children's communication and word use compared with a once-weekly delivery of the same treatment.

Method

Sixty-four children with intellectual and communication delay were randomly assigned to receive 60-min sessions of MCT either 1 time or 5 times per week over a 9-month treatment. Growth curves were fit to data collected at 5 points before, during, and after the MCT was delivered.

Results

With groups collapsed, significant growth across the experimental period was observed on all measures, but this was not associated unconditionally with treatment intensity. Children who played with 9 or more objects during a standard play assessment, an empirically identified cut-point, benefited more from the high- than from the low-intensity treatment on lexical measures (Hedges's
g
range = .49 to .65).

Conclusions

More MCT is not always better for all children. Clinicians can expect that increasing the frequency of MCT sessions will yield moderate enhancement of outcomes if the child has high interest in objects.
Listening Effort With Cochlear Implant Simulations
Authors: Pals Carina , Sarampalis Anastasios , Başkent Deniz
Published: December 2012

Purpose

Fitting a cochlear implant (CI) for optimal speech perception does not necessarily optimize listening effort. This study aimed to show that listening effort may change between CI processing conditions for which speech intelligibility remains constant.

Method

Nineteen normal-hearing participants listened to CI simulations with varying numbers of spectral channels. A dual-task paradigm combining an intelligibility task with either a linguistic or nonlinguistic visual response-time (RT) task measured intelligibility and listening effort. The simultaneously performed tasks compete for limited cognitive resources; changes in effort associated with the intelligibility task are reflected in changes in RT on the visual task. A separate self-report scale provided a subjective measure of listening effort.

Results

All measures showed significant improvements with increasing spectral resolution up to 6 channels. However, only the RT measure of listening effort continued improving up to 8 channels. The effects were stronger for RTs recorded during listening than for RTs recorded between listening.

Conclusion

The results suggest that listening effort decreases with increased spectral resolution. Moreover, these improvements are best reflected in objective measures of listening effort, such as RTs on a secondary task, rather than intelligibility scores or subjective effort measures.
The Development of Language-Specific and Language-Independent Talker Processing
Authors: Levi Susannah V. , Schwartz Richard G.
Published: December 2012

Purpose

In this study, the authors aimed to investigate how differences in language ability relate to differences in processing talker information in the native language and an unfamiliar language by comparing performance for different ages and for groups with impaired language.

Method

Three groups of native English listeners with typical language development (TLD; ages 7–9, ages 10–12, adults) and 2 groups with specific language impairment (SLI; ages 7–9, ages 10–12) participated in the study. Listeners heard pairs of words in both English and German (unfamiliar language) and were asked to determine whether the words were produced by the same or different talkers.

Results

In English, talker discrimination improved with age. In German, performance improved with age for the school-age children but was worse for adult listeners. No differences were found between TLD and SLI children.

Conclusion

These results show that as listeners' language skills develop, there is a trade-off between more general perceptual abilities useful for processing talker information in any language and those that are relevant to their everyday language experiences and, thus, tied to the phonology. The lack of differences between the children with and without language impairments suggests that general auditory processing may be intact in at least some children with SLI.
Linguistic Constraints on Children's Overt Marking of
BE
by Dialect and Age
Authors: Roy Joseph , Oetting Janna B. , Moland Christy Wynn
Published: December 2012

Purpose

Overt marking of
BE
in nonmainstream adult dialects of English is influenced by a number of linguistic constraints, including the structure's person, number, tense, contractibility, and grammatical function. In the current study, the authors examined the effects of these constraints on overt marking of
BE
in children as a function of their nonmainstream English dialect and age.

Method

The data were language samples from 62 children, ages 4–6 years; 24 children spoke African American English (AAE), and 38 spoke Southern White English (SWE). Analyses included analysis of variance and logistic regression.

Results

Rates of overt marking varied by the children's dialect but not their age. Although the person, number, tense, and grammatical function of
BE
influenced the children's rates of marking, the nature and magnitude of the influence differed by the children's dialect. For AAE-speaking children, contractibility also influenced their marking of
BE
.

Conclusions

Consistent with the adult literature, the current study showed that AAE- and SWE-speaking children marked
BE
in ways that differed from each other and from what has been documented for child speakers of Mainstream American English. These findings show stability in the use of
BE
in AAE and SWE that spans different generations and different dialect communities.
The Effect of Homonymy on Learning Correctly Articulated Versus Misarticulated Words
Authors: Storkel Holly L. , Maekawa Junko , Aschenbrenner Andrew J.
Published: December 2012

Purpose

The goal of the current study was to examine the effect of
homonymy
(learning a second meaning for a known word form vs. learning a novel meaning and novel word form) and
articulation accuracy
(IN vs. OUT sounds) on word learning by preschool children. An added goal was to determine whether word frequency altered the effect of homonymy on word learning.

Method

Twenty-nine 3- to 4-year-old children were taught homonyms and novel words. Stimuli further varied in whether homonymy was present in both the adult input and the child's output (as for IN sounds) versus present only in the child's output (as for OUT sounds).

Results

For IN sounds, children learned homonyms more rapidly than novel words. Moreover, the homonym advantage was modulated by word frequency, such that children learned a new meaning for a high-frequency word more accurately than they learned a new meaning for a low-frequency word. In contrast, for OUT sounds, there was no evidence that homonymy influenced learning.

Conclusions

Homonymy in the adult input facilitates word learning by preschool children, whereas homonymy in the child's output alone does not. This effect is captured in a usage-based model of phonology and the lexicon.

Supplemental Material

https://doi.org/10.23641/asha.6170396
Effects of Prior Phonotactic Knowledge on Infant Word Segmentation: The Case of Nonadjacent Dependencies
Authors: Gonzalez-Gomez Nayeli , Nazzi Thierry
Published: December 2012

Purpose

In this study, the authors explored whether French-learning infants use nonadjacent phonotactic regularities in their native language, which they learn between the ages of 7 and 10 months, to segment words from fluent speech.

Method

Two groups of 20 French-learning infants were tested using the head-turn preference procedure at 10 and 13 months of age. In Experiment 1, infants were familiarized with 2 passages: 1 containing a target word with a frequent nonadjacent phonotactic structure and the other containing a target word with an infrequent nonadjacent phonotactic structure in French. During the test phase, infants were presented with 4 word lists: 2 containing the target words presented during familiarization and 2 other control words with the same phonotactic structure. In Experiment 2, the authors retested infants' ability to segment words with the infrequent phonotactic structure.

Results

Ten- and 13-month-olds were able to segment words with the frequent phonotactic structure, but it is only by 13 months, and only under the circumstances of Experiment 2, that infants could segment words with the infrequent phonotactic structure.

Conclusion

These results provide new evidence showing that infant word segmentation is influenced by prior nonadjacent phonotactic knowledge.
Error Variability and the Differentiation Between Apraxia of Speech and Aphasia With Phonemic Paraphasia
Authors: Haley Katarina L. , Jacks Adam , Cunningham Kevin T.
Published: December 2012

Purpose

This study was conducted to evaluate the clinical utility of error variability for differentiating between apraxia of speech (AOS) and aphasia with phonemic paraphasia.

Method

Participants were 32 individuals with aphasia after left cerebral injury. Diagnostic groups were formed on the basis of operationalized measures of recognized articulatory and prosodic characteristics of AOS and phonemic paraphasia. Sequential repetitions of multisyllabic words were elicited as part of a motor speech evaluation and transcribed phonetically. Four metrics of variability at the syllable and word levels were derived from these transcripts.

Results

The measures yielded different magnitudes of variability. There were no group differences between participants who displayed speech profiles consistent with AOS and participants who displayed speech profiles indicative of aphasia with phonemic paraphasia. Rather, correlation coefficients and analyses of covariance showed that the variability metrics were significantly mediated by overall error rate. Additionally, variability scores for individuals with salient diagnoses of AOS and conduction aphasia were inconsistent with current diagnostic guidelines.

Conclusions

The results do not support diagnostic validity of error variability for differentiating between AOS and aphasia with phonemic paraphasia. Future research using error variability metrics should account for overall error rate in the analysis and matching of participant groups.
Nonnative English Speaker Performance on the Basic English Lexicon (BEL) Sentences
Authors: Rimikis Stacey , Smiljanic Rajka , Calandruccio Lauren
Published: December 2012

Purpose

The purpose of this study was to examine sentence-recognition performance for a large, diverse group of nonnative speakers of English on the recently developed Basic English Lexicon (BEL) sentence materials and to determine whether BEL sentence lists are equated in difficulty for this population.

Method

The BEL sentences were presented to 102 nonnative speakers of English with normal hearing and varied linguistic and cultural backgrounds. Five hundred sentences were presented mixed with noise spectrally matched to the target sentences. Subjects completed an online questionnaire providing detailed demographic and linguistic information. Listeners' spoken English proficiency was also assessed using the Versant English Test (Pearson Education, 2010).

Results

Nonnative listeners showed equal word-recognition performance for 3 groups of BEL sentence lists, each group containing sentence lists that had equivalent difficulty. In addition, spoken language proficiency and several demographic and linguistic factors were significantly correlated with BEL performance.

Conclusion

The BEL sentence materials have been tested on a large cohort of nonnative speakers of English and have been found to be appropriate for use in speech-perception testing with this population.
A Review on Prediction Methods for Molar Enthalpies of Vaporization of Hydrocarbons: The ELBA Method as the Best Answer
Authors: Santos Rui C. , Leal João P.
Published: December 2012

A review on prediction methods for molar enthalpies of vaporization at T = 298.15 K of hydrocarbons is presented. A new method is proposed and compared with six of the most common used ones from the literature. This new method, the extended Laidler bond additivity (ELBA), was applied to the prediction of standard molar enthalpies of vaporization of hydrocarbons (alkanes, alkenes, alkynes, polyenes, poly-ynes, cycloalkanes, cycloalkenes, benzene compounds, biphenyl compounds, and polyphenyl compounds) at T = 298.15 K. A total of 260 experimental standard molar enthalpies of vaporization at T = 298.15 K were used for the parameters optimization. Comparison between the experimental values and those calculated using ELBA led to an average absolute difference of 0.35 kJ mol−1, corresponding to an average relative error of 0.92%. In addition, this new method proves to be better than the ones used for comparison with an independent set of 83 experimental standard molar enthalpies of vaporization at T = 298.15 K.
Energy Levels and Observed Spectral Lines of Neutral and Singly Ionized Chromium, Cr I and Cr II
Authors: Saloman E. B.
Published: December 2012

The energy levels and observed spectral lines of neutral and singly ionized chromium atoms have been compiled. Tables of energy levels and spectral lines are generated for each stage. Experimental g-factors and leading percentages are included when available. An experimental value for the ionization energy for each stage is provided.
IUPAC-NIST Solubility Data Series. 96. Amines with Water Part 1. C4–C6 Aliphatic Amines
Authors: Góral Marian , Shaw David G. , Mączyński Andrzej , Wiśniewska-Gocłowska Barbara , Oracz Paweł
Published: December 2012

The mutual solubilities and related liquid-liquid equilibria of 24 binary systems of C4–C6 aliphatic amines with water are exhaustively and critically reviewed. Reports of experimental determination of solubility that appeared in the primary literature prior to the end of 2010 are compiled. For ten systems, sufficient data are available to allow critical evaluation. All data are expressed as mass percent and mole fraction as well as the originally reported units.
Reference Correlation of the Thermal Conductivity of Benzene from the Triple Point to 725 K and up to 500 MPa
Authors: Assael M. J. , Mihailidou E. K. , Huber M. L. , Perkins R. A.
Published: December 2012

This paper contains new, representative reference equations for the thermal conductivity of benzene. The equations are based in part upon a body of experimental data that have been critically assessed for internal consistency and for agreement with theory whenever possible. In the case of the dilute-gas thermal conductivity, a theoretically based correlation was adopted in order to extend the temperature range of the experimental data. Moreover, in the critical region, the experimentally observed enhancement of the thermal conductivity is well represented by theoretically based equations containing just one adjustable parameter. The correlations are applicable for the temperature range from the triple point to 725 K and pressures up to 500 MPa. The overall uncertainty (considered to be estimates of a combined expanded uncertainty with a coverage factor of two) of the proposed correlation is estimated, for pressures less than 350 MPa and temperatures less than 725 K, to be less than 4.4%.
IUPAC-NIST Solubility Data Series. 96. Amines with Water Part 3. Non-Aliphatic Amines
Authors: Góral Marian , Shaw David G. , Mączyński Andrzej , Wiśniewska-Gocłowska Barbara , Oracz Paweł
Published: December 2012

The mutual solubilities and related liquid-liquid equilibria of 36 binary systems of non-aliphatic amines with water are exhaustively and critically reviewed. Reports of experimental determination of solubility that appeared in the primary literature prior to the end of 2010 are compiled. For 13 systems, sufficient data are available to allow critical evaluation. All data are expressed as mass percent and mole fraction as well as the originally reported units.
Recommended Viscosities of 11 Dilute Gases at 25 °C
Authors: Berg Robert F. , Moldover Michael R.
Published: December 2012

Commercially manufactured meters that measure the flow of a process gas are often calibrated with a known flow of a surrogate gas. This requires an accurate model of the flow meter and accurate values of the relevant thermophysical properties for both gases. In particular, calibrating a “laminar” flow meter near ambient temperature and pressure requires that the ratio (process gas viscosity)/(surrogate gas viscosity) be known to approximately 0.1%. With this motivation, we critically reviewed measurements of viscosity conducted with 18 instruments near 25 °C and zero density for 11 gases: He, Ne, Ar, Kr, Xe, H2, N2, CH4, C2H6, C3H8, and SF6. For these gases and this single state, we determined viscosity ratios with relative standard uncertainties ranging from 2.7 × 10−4 to 3.6 × 10−4 at a 68% confidence level. Anchoring the ratios to the value (19.8253 ± 0.0002) × 10−6 Pa s for the viscosity of helium calculated ab initio at 25 °C and zero density yields recommended values for the other ten gases and establishes a scale for gas viscosities that is more accurate than most of the reported values. To facilitate the extension of this scale, we recommend that researchers who calibrate gas viscometers (1) use helium as a calibration gas when possible, (2) report the values of all calibration data, and (3) report the uncertainties of their measured viscosity ratios. Similarly, we recommend that data archives capture this relevant calibration information.
Recommended Correlations for the Surface Tension of Common Fluids
Authors: Mulero A. , Cachadiña I. , Parra M. I.
Published: December 2012

Available values of the surface tension of 81 common fluids were fitted by using the same model presently used in the REFPROP program V9.0 by NIST. A set of data was built for every fluid by including mainly those values given in the DIPPR and DETHERM databases. For some fluids, other available sources of data were added in order to obtain adequate sets. For every fluid, we checked the accuracy of the REFPROP program and we made a new fit in order to improve the performance of the correlation. We found good general agreement between the REFPROP predictions and the data for 44 fluids, and therefore only very slight improvements are made for them. For the other 37 fluids, the REFPROP correlation can be more clearly improved. In particular, our new correlation is significantly more accurate for ammonia, deuterium, ethanol, and neon, because the version of REFPROP used gives values in clear disagreement with other data sources.
An efficient multi-scale lattice model approach to screening nano-porous adsorbents
Authors: Yu Kuang , McDaniel Jesse G. , Schmidt J. R.
Published: December 2012

We present a multi-scale, hierarchical, approach for developing lattice models to estimate adsorption in nano-porous sorbents, derived on the basis of underlying atomistic potentials. This approach is a generalization of earlier work in zeolites (where the specific adsorption sites are easily definable) to encompass both specific as well as diffuse adsorption; the latter often dominates in the case of nano-porous metal-organic frameworks (MOFs). In conjunction with appropriately coarse grained guest-guest interactions, we demonstrate that our lattice approach offers semi-quantitative to quantitative agreement as compared to fully atomistic simulation from the low pressure regime through saturation. However, it also yields orders-of-magnitude acceleration versus the latter, thus enabling high-throughput screenings of both non-polar and polar adsorbates with high efficiency. We also show how our lattice model can be extended to facilitate rapid, qualitative screening of transport properties via appropriate calibration. Although our example applications focus on CO2 adsorption in MOFs, this approach is readily generalizable to various nano-porous materials (MOFs, zeolites…) and guest adsorbates (CO2, H2, hydrocarbons).
Improved performance of flexible amorphous silicon solar cells with silver nanowires
Authors: Chen Y. R. , Li Z. Q. , Chen X. H. , Liu C. , Ye X. J. , Wang Z. B. , Sun Z. , Huang S. M.
Published: December 2012

A novel hybrid electrode structure using Ag nanowires (NWs) to create surface plasmons to enhance light trapping is designed and applied on the front surface of hydrogenated amorphous silicon (a-Si:H) solar cells on steel substrates, targeting broad-band absorption enhancements. Ag NWs were synthesized using a soft and self-seeding process. The produced Ag NWs were deposited on indium tin oxide (ITO) glass substrates or the ITO layers of the as-prepared flexible a-Si:H solar cells to form Ag NW-ITO hybrid electrodes. The Ag NW-ITO hybrid electrodes were optimized to achieve maximum optical enhancement using surface plasmons and obtain good electrical contacts in cells. Finite-element electromagnetic simulations confirmed that the presence of the Ag NWs resulted in increased electromagnetic fields within the a-Si:H layer. Compared to the cell with conventional ITO electrode, the measured quantum efficiency of the best performing a-Si:H cell shows an obvious enhancement in the wavelength range from 330 nm to 600 nm. The cell based on the optimized Ag NW-ITO demonstrates an increase about 4% in short-circuit current density and over 6% in power conversion efficiency under AM 1.5 illumination.
Diagnosing the plasma nonuniformity in an iron opacity experiment by spatially resolved Al 1s-2p absorption spectroscopy
Authors: Xiaoding Zhang , Jiyan Zhang , Yang Zhao , Gang Xiong , Bin Zhao , Guohong Yang , Jian Zheng , Jiamin Yang
Published: December 2012

Generating a well-characterized hot-dense sample is of great importance to high quality opacity measurements. In this paper, we report on an experimental investigation of the plasma nonuniformity in a radiatively heated iron opacity sample by spatially resolved Al 1s-2p absorption spectroscopy. The iron sample was tamped by plastic at both sides and was heated by thermal x-ray radiation generated in a gold Hohlraum, and an Al layer attached to it was used as a tracer for temperature diagnosis. Spatially resolved 1s-2p transition absorption spectra of the Al tracer were measured by the technique of point-projection-spectroscopy, and temperatures in the sample were obtained by comparing the measured spectra with detailed-term-accounting model calculations, with the density of the sample deduced using a combination of side-on radiography and radiative hydrodynamic simulation. The results showed the existence of axial temperature nonuniformity in the sample, and these temperature variations have been used to explain the shift of iron 2p-3d transition absorption feature along the axial direction of the Hohlraum used to heat the sample successfully.
Formation of surface nano-structures by plasma expansion induced by highly charged ions
Authors: Moslem W. M. , El-Said A. S.
Published: December 2012

Slow highly charged ions (HCIs) create surface nano-structures (nano-hillocks) on the quartz surface. The formation of hillocks was only possible by surpassing a potential energy threshold. By using the plasma expansion approach with suitable hydrodynamic equations, the creation mechanism of the nano-hillocks induced by HCIs is explained. Numerical analysis reveal that within the nanoscale created plasma region, the increase of the temperature causes an increase of the self-similar solution validity domain, and consequently the surface nano-hillocks become taller. Furthermore, the presence of the negative (positive) nano-dust particles would lead to increase (decrease) the nano-hillocks height.
Communication: Rovibrationally selected absolute total cross sections for the reaction H2O+(X2B1; v1+v2+v3+ = 000; N+Ka+Kc+) + D2: Observation of the rotational enhancement effect
Authors: Xu Yuntao , Xiong Bo , Chang Yih Chung , Ng C. Y.
Published: December 2012

By employing the newly established vacuum ultraviolet laser pulsed field ionization-photoion (PFI-PI) double quadrupole-double octopole ion guide apparatus, we have measured the rovibrationally selected absolute total cross sections of the ion-molecule reaction H2O+(X2B1; v1+v2+v3+ = 000; N+Ka+Kc+) + D2 → H2DO+ + D in the center-of-mass collision energy (Ecm) range of 0.05–10.00 eV. The pulsing scheme used for the generation of PFI-PIs has made possible the preparation of reactant H2O+(X2B1; v1+v2+v3+ = 000) ions in single N+Ka+Kc+ rotational levels with high kinetic energy resolutions. The absolute total cross sections observed in different N+Ka+Kc+ levels with rotational energies in the range of 0–200 cm−1 were found to exhibit a significant rotational enhancement on the reactivity for the titled reaction. In contrast, the measured cross sections reveal a decreasing trend with increasing Ecm, indicating that the rotational enhancement observed is not a total energy effect, but a dynamical effect. Furthermore, the rotational enhancement is found to be more pronounced as Ecm is decreased. This experiment provided evidence that the coupling of the core rotational angular momentum with the orbital angular momentum could play a role in chemical reactivity, particularly at low Ecm.
Dielectric and enhanced pyroelectric properties of (Pb0.325Sr0.675)TiO3 ceramics under direct current bias field
Authors: Lei Xiuyun , Dong Xianlin , Mao Chaoliang , Chen Ying , Cao Fei , Wang Genshui
Published: December 2012

(Pb0.325Sr0.675)TiO3 (PST) ceramics were prepared by a traditional solid-state reaction technique. The dielectric and enhanced pyroelectric properties of PST ceramics were investigated under a DC bias field. The dielectric permittivity and dielectric loss of PST ceramics at Curie temperature were 2.97 × 10−4 and 0.006 without DC bias field, respectively. With a DC electric field of 0–500 V/mm, the maximum pyroelectric coefficient and the largest figure of merit (Fd) of PST ceramics were obtained, about 60 × 10−8 C cm−2 K−1 and 26 × 10−5 Pa−1/2, respectively. PST ceramics with such superior electric field enhanced pyroelectric properties have the potential for uncooled focal plane array detectors application.
Magnetoresistive effect of a topological-insulator waveguide in the presence of a magnetic field
Authors: Li Yuan , Jalil Mansoor B. A. , Ghee Tan Seng , Zhou Guanghui , Qian Zhenghong
Published: December 2012

We investigate the transport properties of a topological insulator (TI) waveguide in the presence of an external magnetic field. We demonstrate that the magnetic field can modulate the energy gap induced by the transverse confinement and may even result in the closure of the band gap. The dependence of the magnetic field and the temperature on the magnetoresistance (MR) is also analyzed. The MR ratio increases linearly and exhibits a nonsaturation behaviour at high fields. The MR behavior also exhibits weak temperature dependence such that a high MR is maintained over a broad temperature range. The robustness of the MR up to room temperature can be exploited for magneto-electronic device applications.
Layer-by-layer processed high-performance polymer solar cells
Authors: Li Hui , Wang Jizheng
Published: December 2012

Layer-by-layer (LL) process has great potential in achieving high-performance polymer solar cells (PSCs) due to its advantage in realizing p-i-n like structure. LL method is attracting more and more interests in fabricating PSCs, and power conversion efficiency (PCE) of LL processed PSCs has been greatly improved to over 5% recently. In this paper, by employing LL approach, we fabricated polymer photovoltaic devices with poly(3-hexylthiophene) (P3HT) as donor and four different fullerenes as acceptor. PCE of 6.48% was achieved. Performances of the LL processed devices are comparatively better than that of their corresponding traditional bulk-heterojunction devices.
Cooling molecules the optoelectric way
Authors: Miller Johanna L.
Published: December 2012

In a newly implemented technique, the complex rotational and vibrational motions of molecules are not a hindrance but a help.
Droplets deform in a solid at high voltage
Authors: Wilson R. Mark
Published: December 2012

The first observations of shape-shifting droplets in a rubbery polymer reveal the connection between fluid instabilities and dielectric breakdown.
A liquid ground state for 2D helium-3?
Authors: Smart Ashley G.
Published: December 2012

New experiments hint at what could be the lowest-density liquid ever found in nature.
Russia launches S&T university
Authors: Feder Toni
Published: December 2012

The top-down initiative aims to be interdisciplinary and international and to breed entrepreneurship.
Norman Ramsey and his method
Authors: Kleppner Daniel
Published: December 2012

While searching for a way to boost the resolution of an atomic spectrometer, Ramsey hit on a simple solution: Replace a single oscillating magnetic field with two separated ones.
Atomic clocks for controlling light fields
Authors: Haroche Serge , Brune Michel , Raimond Jean-Michel
Published: December 2012

Norman Ramsey’s interferometer has matured into a tool that can nondestructively detect the birth and death of single photons, prepare photon number states via feedback loops, and entangle atoms and photons into Schrödinger-cat states.
The method of successive oscillatory fields
Authors: Ramsey Norman F.
Published: December 2012

An extension of Rabi’s molecular-beam resonance method, originally devised for measuring nuclear magnetic moments, is proving useful also for microwave spectroscopy, masers and lasers.
Carried by impulse: The physics of water jetpacks
Authors: Vonk Matthew , Bohacek Peter
Published: December 2012

A jetpack can suspend a pilot in midair, in a way reminiscent of a magic carpet. But the magic is all in mechanical forces that can be readily estimated.
ADAR1 promotes malignant progenitor reprogramming in chronic myeloid leukemia
Authors: Jiang Qingfei , Crews Leslie A. , Barrett Christian L. , Chun Hye-Jung , Court Angela C. , Isquith Jane M. , Zipeto Maria A. , Goff Daniel J. , Minden Mark , Sadarangani Anil , Rusert Jessica M. , Dao Kim-Hien T. , Morris Sheldon R. , Goldstein Lawrence S. B. , Marra Marco A. , Frazer Kelly A. , Jamieson Catriona H. M.
Published: December 2012

The molecular etiology of human progenitor reprogramming into self-renewing leukemia stem cells (LSC) has remained elusive. Although DNA sequencing has uncovered spliceosome gene mutations that promote alternative splicing and portend leukemic transformation, isoform diversity also may be generated by RNA editing mediated by adenosine deaminase acting on RNA (ADAR) enzymes that regulate stem cell maintenance. In this study, whole-transcriptome sequencing of normal, chronic phase, and serially transplantable blast crisis chronic myeloid leukemia (CML) progenitors revealed increased IFN-γ pathway gene expression in concert with BCR-ABL amplification, enhanced expression of the IFN-responsive ADAR1 p150 isoform, and a propensity for increased adenosine-to-inosine RNA editing during CML progression. Lentiviral overexpression experiments demonstrate that ADAR1 p150 promotes expression of the myeloid transcription factor PU.1 and induces malignant reprogramming of myeloid progenitors. Moreover, enforced ADAR1 p150 expression was associated with production of a misspliced form of GSK3β implicated in LSC self-renewal. Finally, functional serial transplantation and shRNA studies demonstrate that ADAR1 knockdown impaired in vivo self-renewal capacity of blast crisis CML progenitors. Together these data provide a compelling rationale for developing ADAR1-based LSC detection and eradication strategies.
Evolutionary inference via the Poisson Indel Process
Authors: Bouchard-Côté Alexandre , Jordan Michael I.
Published: December 2012

We address the problem of the joint statistical inference of phylogenetic trees and multiple sequence alignments from unaligned molecular sequences. This problem is generally formulated in terms of string-valued evolutionary processes along the branches of a phylogenetic tree. The classic evolutionary process, the TKF91 model [Thorne JL, Kishino H, Felsenstein J (1991) J Mol Evol 33(2):114–124] is a continuous-time Markov chain model composed of insertion, deletion, and substitution events. Unfortunately, this model gives rise to an intractable computational problem: The computation of the marginal likelihood under the TKF91 model is exponential in the number of taxa. In this work, we present a stochastic process, the Poisson Indel Process (PIP), in which the complexity of this computation is reduced to linear. The Poisson Indel Process is closely related to the TKF91 model, differing only in its treatment of insertions, but it has a global characterization as a Poisson process on the phylogeny. Standard results for Poisson processes allow key computations to be decoupled, which yields the favorable computational profile of inference under the PIP model. We present illustrative experiments in which Bayesian inference under the PIP model is compared with separate inference of phylogenies and alignments.
First Report of Pineapple Heart Rot Caused by Phytophthora nicotianae in Hainan Province, China
Authors: Shen H. F. , Lin B. R. , Zhan J. X. , Pu X. M.
Published: December 2012

Pineapple (Ananas comosus) is an economically important tropical fruit in Hainan Province, China. During September to November 2011, heart rot disese of pineapple was found in Ledong and Wangning of Hainan Province. A survey of 150 ha producing areas of pineapple revealed that the fields were affected at an incidence ranging from 25% to 30%. Infected plants showed water-soaked lesions and soft rot on the base of heart leaves near the soil surface. Heart leaves of infected plants were easily pulled out. As the disease progressed, plants collapsed and died. Diseased tissue fragments (2 × 2 mm) were surface-disinfected for 10 min with 0.3% NaClO, then rinsed three times in sterile water, and plated to 10% V8 juice agar (4). Inoculated dishes were incubated at 26°C in the dark. After 5 days, Phytophthora (identified by the presence of coenocytic hyphae and papillate sporangia) were isolated from the tissue cultures, which has aseptate hyphae. Sporangia were papillate, noncaducous, oval or spherical, and 34.5 to 58.2 μm. Clamydospores, both terminal and intercalary, were also spherical, and were 23.4 to 34.0 μm (2). The ITS region of rDNA was amplified using primers ITS4/ITS5, and the 927-bp product of the ITS showed 99% sequence identity to Phytophthora nicotianae (GenBank Accession No. JF792540), and the sequence was accessed to NCBI (JX978446). Pathogenicity tests were confirmed by irrigating the wounded stem bases of 10 2-month-old pineapple plants with 50 ml of P. nicotionae zoospore solution (15,000 zoospores/ml), and another 10 plants of the same cultivar inoculated with sterile water served as controls. Plants were placed in pots in a greenhouse at 28°C and 90% relative humidity. After 9 days, soft rot was observed clearly on the base of heart leaves of all 10 inoculated plants, while the control plants appeared normal. P. nicotianae was reisolated from the infected pineapple plants, and confirmed to be the same as the inoculated pathogen by conducting a ITS rDNA sequence comparison and morphological characteristics. P. nicotianae was previously reported as the causal agent of heart rot of pineapple in Hawaii, U.S.A. (3) and Guangdong Province of China (1). To our knowledge, this is the first report of P. nicotianae on pineapple in Hainan Province, China.

References: (1) J. Z. Chen et al. J. Yunnan Agric. Univ. 8:134, 2003. (2) H. H. Ho. Mycologia 73:705, 1981.(3) K. W. Howard et al. Plant Dis. Rep. 48:848, 1964. (4) X. B. Zheng. Page 81 in: Phytophthora and its Research Technology. China Agricultural Press, Beijing, 1997.
The Influence of Common Medical Conditions on the Outcome of Anterior Lumbar Interbody Fusion
Authors: Kalb Samuel , Perez-Orribo Luis , Kalani Mohammad Yashar S. , Snyder Laura A. , Martirosyan Nikolay L. , Burns Keven , Standerfer Robert J. , Kakarla Udaya K. , Dickman Curtis A. , Theodore Nicholas
Published: December 2012

Study Design:

The authors retrospectively reviewed a consecutive series of 231 patients with anterior lumbar interbody fusion (ALIF).

Objective:

To determine the correlations among common medical conditions, demographics, and the natural history of lumbar surgery with outcomes of ALIF.

Summary of Background Data:

Multiple spinal disorders are treated with ALIF with excellent success rates. Nonetheless, adverse outcomes and complications related to patients’ overall demographics, comorbidities, or cigarette smoking have been reported.

Methods:

The age, sex, body mass index (BMI), comorbidities, history of smoking or previous lumbar surgery, operative parameters, and complications of 231 patients who underwent ALIF were analyzed. Regression analyses of all variables with complications and surgical outcomes based on total Prolo scores were performed. Two models predicting Prolo outcome score were generated. The first model used BMI and sex interaction, whereas the second model used sex, level of surgery, presence of diabetes mellitus, and BMI as variables.

Results:

At follow-up, the rate of successful fusion was 99%. The overall complication rate was 13.8%, 1.8% of which occurred intraoperatively and 12% during follow-up. The incidence of complications failed to correlate with demographics, comorbidities, smoking, or previous lumbar surgery (P>0.5). ALIF at T12–L4 was the only factor significantly associated with poor patient outcomes (P=0.024). Both models successfully predicted outcome (P=0.05), although the second model did so only for males.

Conclusions:

Surgical level of ALIF correlated with poor patient outcomes as measured by Prolo functional scale. BMI emerged as a significant predictor of Prolo total score. Both multivariate models also successfully predicted outcomes. Surgical or follow-up complications were not associated with patients’ preoperative status.
Aortic Dissection Type a after Right Atrial Cryoablation during Port Access Mitral Valve Surgery
Authors: Fleck Tatjana , Dworschak Martin , Wisser Wilfried
Published: December 2012

The case of a 63-year-old woman who underwent minimal invasive mitral and tricuspid valve repair and a concomitant CryoMaze is described. During creation of the last lesion of the right-sided maze procedure, dissection of the ascending aorta occurred that necessitated emergency sternotomy, replacement of the ascending aorta, and aortocoronary bypass grafting to the right coronary artery (RCA) because of detachment of the RCA from the aortic annulus. Repair of this complication was successful; nevertheless, the patient died 5 days after the operation because of multiorgan failure. The cause of this complication can only be speculated, but a relation to the CyroMaze is obvious. Because of the restricted incision with impaired vision especially in the area of the right atrial appendage, the cryoprobe could have come into contact with the orifice of the RCA during the last lesion, with subsequent detachment of the RCA from the aorta, which could subsequently have caused dissection.
Achieving Renal Denervation: Catheter-Based and Surgical Management for Neural Ablation in the Management of Hypertension
Authors: Sodha Neel R. , Moore Hans J. , Papademetriou Vasilios , Trachiotis Gregory D.
Published: December 2012

Hypertension refractory to conventional management with medication remains a significant cause of cardiovascular morbidity and mortality. Alternative strategies are warranted in this subgroup of patients. The target of these strategies centers around sympathetic neural activity, which is thought to play a key role in hypertension. We will review the historic and current approaches toward altering sympathetic neural activity, specifically discussing surgical sympathectomy, catheter-based renal denervation strategies, and baroreflex activation therapy.
The PleuraFlow Active Chest Tube Clearance System: Initial Clinical Experience in Adult Cardiac Surgery
Authors: Perrault Louis P. , Pellerin Michel , Carrier Michel , Cartier Raymond , Bouchard Denis , Demers Philippe , Boyle Edward M.
Published: December 2012

Objective

To address the clinical consequences related to chest tube clogging, a novel chest drainage apparatus, the PleuraFlow Active Tube Clearance System (Clear Catheter Systems, Bend, OR), was developed. The aim of this world's first clinical experience study was to follow clinicians using the PleuraFlow system to assess usability issues and potential areas of improvement in the heart surgery setting.

Methods

A user preference study was conducted to assess how specified users (surgeons, nurses, and intensive care physicians) used the PleuraFlow system to achieve specified goals in an efficient manner. Data were collected from patient charts and by a questionnaire that they had filled.

Results

All the surgeons (n = 7) noted that the device was not any more difficult to insert than a conventional chest tube and was easy to assemble and use. There were no reports of malfunction or complications related to the installation or use of the system. A majority, 77% (24/31), of nurses felt that the device was more time efficient than stripping, milking, or tapping the chest tubes to keep them open. A majority (16/19, 84%) of the PleuraFlow chest tubes and guide tubes were removed together in one piece within 1 day of surgery (on postoperative day 1).

Conclusions

Overall, the physicians and nurses rated the PleuraFlow system positively for its ability to be incorporated into the postoperative workflow of managing the drainage of patients after heart surgery. This device may be useful to allow caregivers to be certain that chest tubes are functioning in the early hours after surgery, when active bleeding is resolving and when complications from undrained blood can ensue.
Evaluation of Patient Safety Culture: A Survey of Clinicians in a Cardiovascular Operating Room
Authors: Henry Linda , Hunt Sharon L. , Kroetch Mary , Yang Y. Tony
Published: December 2012

Objective

The aim of this study was to understand the perceived safety culture and attitudes of caregivers in a large cardiovascular operating room (CVOR) in a mid-Atlantic state where more than 1500 procedures are performed annually to include ventricular assist device placement and heart and lung transplantations.

Methods

We analyzed deidentified data obtained from a safety survey completed anonymously by frontline caregivers in the CVOR via the Safety Attitudes Questionnaire developed by Pasquel Metrics.

Results

The responses from the CVOR clinicians were overall positive for their perceptions of the CVOR safety climate, with the majority saying they would feel safe being treated as a patient, liked their job, and were aware of the proper channels regarding patient safety. However, many made claims of experiencing fatigue and stress due to an excessive workload and participation in emergency situations. Furthermore, the support/clinical perfusion teams were found to have experienced the greatest amount of stress and discomfort, whereas it seems the surgeons were impacted the least.

Conclusions

This study suggests that reactions to different situations in the operating room are dependent on the role of the caregiver. Therefore, interventions to improve communication among the caregivers must be geared on an individual group basis.