Understanding Writing Problems in Young Children: Contributions of Cognitive Skills to the Development of Written Expression

ERIC Educational Resources Information Center

Childress, Amy

2011-01-01

While several models of adult writing have been proposed and studied, the development of writing skills in young children has only recently garnered attention. Using measures of fine-motor, language, working memory, and attention/executive functions, the current study explored motor and cognitive skills that may contribute to writing skill in…

Vision science literature of Nepal in the database "Web of Science".

PubMed

Risal, S; Prasad, H N

2012-01-01

Vision Science is considered to be a quite developed discipline in Nepal, with much research currently in progress. Though the results of these endeavors are published in scientific journals, formal citation analyses have not been performed on works contributed by Nepalese vision scientists. To study Nepal's contribution to vision science literature in the database "Web of Science". The primary data source of this paper was Web of Science, a citation database of Thomas Reuters. All bibliometric analyses were performed with the help of Web of Science analysis service. In the current database of vision science literature, Nepalese authors contributed 112 publications to Web of Science, 95 of which were original articles. Pokharel GP had the highest number of citations among contributing authors of Nepal. Hennig A contributed the highest number of article as a first author. The Nepal Eye Hospital contributed the highest number of articles as an institution to the field of Vision Science. Currently, only two journals from Nepal including Journal of Nepal Medical Association (JAMA) are indexed in the Web of Science database (Sieving, 2012). To evaluate the total productivity of vision science literature from Nepal, total publication counts from national journals and articles indexed in other databases such as PubMed and Scopus must also be considered. © NEPjOPH.

Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

NASA Astrophysics Data System (ADS)

Lühr, Hermann; Xiong, Chao; Olsen, Nils; Le, Guan

2017-03-01

Magnetospheric currents play an important role in the electrodynamics of near-Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field. Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like Ørsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing in the magnetospheric tail. Also their magnetic contribution at LEO orbits is non-negligible. Treating them as an independent source is a more recent development, which has cured some of the problems in geomagnetic field modelling. Unfortunately there is no index available for characterising the tail current intensity. Here we propose an approach that may help to properly quantify the magnetic contribution from the tail current for geomagnetic field modelling. Some open questions that require further investigation are mentioned at the end.

Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

NASA Technical Reports Server (NTRS)

Luehr, Hermann; Xiong, Chao; Olsen, Nils; Le, Guan

2016-01-01

Magnetospheric currents play an important role in the electrodynamics of near- Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field. Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like Ørsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing in the magnetospheric tail. Also their magnetic contribution at LEO orbits is non-negligible. Treating them as an independent source is a more recent development, which has cured some of the problems in geomagnetic field modelling. Unfortunately there is no index available for characterizing the tail current intensity. Here we propose an approach that may help to properly quantify the magnetic contribution from the tail current for geomagnetic field modelling. Some open questions that require further investigation are mentioned at the end.

Contribution of Field Strength Gradients to the Net Vertical Current of Active Regions

NASA Astrophysics Data System (ADS)

Vemareddy, P.

2017-12-01

We examined the contribution of field strength gradients for the degree of net vertical current (NVC) neutralization in active regions (ARs). We used photospheric vector magnetic field observations of AR 11158 obtained by Helioseismic and Magnetic Imager on board SDO and Hinode. The vertical component of the electric current is decomposed into twist and shear terms. The NVC exhibits systematic evolution owing to the presence of the sheared polarity inversion line between rotating and shearing magnetic regions. We found that the sign of shear current distribution is opposite in dominant pixels (60%–65%) to that of twist current distribution, and its time profile bears no systematic trend. This result indicates that the gradient of magnetic field strength contributes to an opposite signed, though smaller in magnitude, current to that contributed by the magnetic field direction in the vertical component of the current. Consequently, the net value of the shear current is negative in both polarity regions, which when added to the net twist current reduces the direct current value in the north (B z > 0) polarity, resulting in a higher degree of NVC neutralization. We conjecture that the observed opposite signs of shear and twist currents are an indication, according to Parker, that the direct volume currents of flux tubes are canceled by their return currents, which are contributed by field strength gradients. Furthermore, with the increase of spatial resolution, we found higher values of twist, shear current distributions. However, the resolution effect is more useful in resolving the field strength gradients, and therefore suggests more contribution from shear current for the degree of NVC neutralization.

Contributions of two types of calcium channels to synaptic transmission and plasticity.

PubMed

Edmonds, B; Klein, M; Dale, N; Kandel, E R

1990-11-23

In Aplysia sensory and motor neurons in culture, the contributions of the major classes of calcium current can be selectively examined while transmitter release and its modulation are examined. A slowly inactivating, dihydropyridine-sensitive calcium current does not contribute either to normal synaptic transmission or to any of three different forms of plasticity: presynaptic inhibition, homosynaptic depression, and presynaptic facilitation. This current does contribute, however, to a fourth form of plasticity--modulation of transmitter release by tonic depolarization of the sensory neuron. By contrast, a second calcium current, which is rapidly inactivating and dihydropyridine-insensitive, contributes to release elicited by the transient depolarization of an action potential and to the other three forms of plasticity.

What Elements in a Sustainability Course Contribute to Paradigm Change and Action Competence? A Study at Lincoln University, New Zealand

ERIC Educational Resources Information Center

Piasentin, Flora Bonazzi; Roberts, Lin

2018-01-01

A significant shift in the dominant paradigm governing the relationship of humans with nature and society is crucial in order to change the current unsustainable practices. This article describes a pilot-study based on a Masters level sustainability course, which explored what specific content, activities and resources may contribute to promoting…

Day-to-day variability of midlatitude ionospheric currents due to magnetospheric and lower atmospheric forcing

NASA Astrophysics Data System (ADS)

Yamazaki, Y.; Häusler, K.; Wild, J. A.

2016-07-01

As known from previous studies on the solar quiet (Sq) variation of the geomagnetic field, the strength and pattern of ionospheric dynamo currents change significantly from day to day. The present study investigates the relative importance of two sources that contribute to the day-to-day variability of the ionospheric currents at middle and low latitudes. One is high-latitude electric fields that are caused by magnetospheric convection, and the other is atmospheric waves from the lower atmosphere. Global ionospheric current systems, commonly known as Sq current systems, are simulated using the National Center for Atmospheric Research thermosphere-ionosphere-mesosphere-electrodynamics general circulation model. Simulations are run for 1-30 April 2010 with a constant solar energy input but with various combinations of high-latitude forcing and lower atmospheric forcing. The model well reproduces geomagnetic perturbations on the ground, when both forcings are taken into account. The contribution of high-latitude forcing to the total Sq current intensity (Jtotal) is generally smaller than the contribution of wave forcing from below 30 km, except during active periods (Kp≥4), when Jtotal is enhanced due to the leakage of high-latitude electric fields to lower latitudes. It is found that the penetration electric field drives ionospheric currents at middle and low latitudes not only on the dayside but also on the nightside, which has an appreciable effect on the Dst index. It is also found that quiet time day-to-day variability in Jtotal is dominated by symmetric-mode migrating diurnal and semidiurnal tidal winds at 45-60° latitude at ˜110 km.

On contribution of energetic and heavy ions to the plasma pressure: Storm Sept 27 - Oct 4, 2002

NASA Astrophysics Data System (ADS)

Kronberg, E. A.; Mouikis, C.; Kistler, L. M.; Dandouras, I. S.; Daly, P. W.; Welling, D. T.; Grigorenko, E. E.

2015-12-01

Contribution of the energetic ions (>> 40 keV) and of heavy ions into the total plasma pressure is often neglected. In this study we evaluate the contribution of these components for the storm observed from September 27 to October 4 in 2002. The thermal component of the pressure for the protons, helium and oxygen at 0--40 keV/q is measured by the Cluster/CIS/CODIF sensor. The contribution of the energetic ions at energies >> 40 keV is calculated from the Cluster/RAPID/IIMS observations. The results show that before the storm has initiated, the contribution of the energetic ions in to the total pressure is indeed negligible in the tail plasma sheet, less than ˜1%. However, with the storm development contribution of the energetic part becomes significant, up to ˜30%, towards the recovery phase and cannot be neglected. Heavy ions contribute to the 27% of the total pressure and half of them are energetic. The contribution of energetic ions to the pressure of the ring current (L≃5) is significant. The heavy ions play a dominant role in the plasma pressure, about 62% during the main phase of the magnetic storm. Half of them are energetic ions. The SWMF/BATS-R-US MHD model underestimates the contribution of the energetic and heavy ions in to the ion distribution in the magnetotail plasma sheet and the ring current. The ring current plasma pressure distorts the terrestrial internal magnetic field and defines magnetic storm. Therefore, it is essential to take in to account the contribution of the energetic and heavy ions.

Study on electrical current variations in electromembrane extraction process: Relation between extraction recovery and magnitude of electrical current.

PubMed

Rahmani, Turaj; Rahimi, Atyeh; Nojavan, Saeed

2016-01-15

This contribution presents an experimental approach to improve analytical performance of electromembrane extraction (EME) procedure, which is based on the scrutiny of current pattern under different extraction conditions such as using different organic solvents as supported liquid membrane, electrical potentials, pH values of donor and acceptor phases, variable extraction times, temperatures, stirring rates, different hollow fiber lengths and the addition of salts or organic solvents to the sample matrix. In this study, four basic drugs with different polarities were extracted under different conditions with the corresponding electrical current patterns compared against extraction recoveries. The extraction process was demonstrated in terms of EME-HPLC analyses of selected basic drugs. Comparing the obtained extraction recoveries with the electrical current patterns, most cases exhibited minimum recovery and repeatability at the highest investigated magnitude of electrical current. . It was further found that identical current patterns are associated with repeated extraction efficiencies. In other words, the pattern should be repeated for a successful extraction. The results showed completely different electrical currents under different extraction conditions, so that all variable parameters have contributions into the electrical current pattern. Finally, the current patterns of extractions from wastewater, plasma and urine samples were demonstrated. The results indicated an increase in the electrical current when extracting from complex matrices; this was seen to decrease the extraction efficiency. Copyright © 2015 Elsevier B.V. All rights reserved.

The Efficacy of Supplemental Early Literacy Instruction by Community-Based Tutors for Preschoolers Enrolled in Head Start

ERIC Educational Resources Information Center

Nelson, J. Ron; Sanders, Elizabeth; Gonzalez, Jorge E.

2010-01-01

Broadly, the current study contributes to the growing body of evidence supporting the positive effects of PA (phonological awareness) interventions for preschoolers, demonstrating that PA instruction need not be postponed until kindergarten. Specifically, the current study addresses the paucity of research on PA training in preschool by testing…

Genetics of Opioid Dependence: A Review of the Genetic Contribution to Opioid Dependence

PubMed Central

Mistry, Chetna J; Bawor, Monica; Desai, Dipika; Marsh, David C; Samaan, Zainab

2014-01-01

This narrative review aims to provide an overview of the impact of opioid dependence and the contribution of genetics to opioid dependence. Epidemiological data demonstrate that opioid dependence is a global trend with far-reaching effects on the social, economic, and health care systems. A review of classical genetic studies of opioid use suggests significant heritability of drug use behavior, however the evidence from molecular genetic studies is inconclusive. Nonetheless, certain genetic variants are important to consider given their role in the pathophysiology of addictive behavior. We undertook a literature review to identify the current state of knowledge regarding the role of genes in opioid dependence. Determining the association of genetic markers could change the current understanding of the various factors contributing to opioid dependence and therefore may improve recognition of individuals at risk for the disorder and prevention and treatment strategies. PMID:25242908

Electromigration failures under bidirectional current stress

NASA Astrophysics Data System (ADS)

Tao, Jiang; Cheung, Nathan W.; Hu, Chenming

1998-01-01

Electromigration failure under DC stress has been studied for more than 30 years, and the methodologies for accelerated DC testing and design rules have been well established in the IC industry. However, the electromigration behavior and design rules under time-varying current stress are still unclear. In CMOS circuits, as many interconnects carry pulsed-DC (local VCC and VSS lines) and bidirectional AC current (clock and signal lines), it is essential to assess the reliability of metallization systems under these conditions. Failure mechanisms of different metallization systems (Al-Si, Al-Cu, Cu, TiN/Al-alloy/TiN, etc.) and different metallization structures (via, plug and interconnect) under AC current stress in a wide frequency range (from mHz to 500 MHz) has been study in this paper. Based on these experimental results, a damage healing model is developed, and electromigration design rules are proposed. It shows that in the circuit operating frequency range, the "design-rule current" is the time-average current. The pure AC component of the current only contributes to self-heating, while the average (DC component) current contributes to electromigration. To ensure longer thermal-migration lifetime under high frequency AC stress, an additional design rule is proposed to limit the temperature rise due to self-joule heating.

PAIRED-CITY STUDY TO DETERMINE THE CONTRIBUTION OF SOURCE WATER TYPE TO THE ENDEMIC LEVEL OF MICROBIAL DISEASE

EPA Science Inventory

Paired-City Study to Determine the Contribution of Source Water Type to the Endemic Level of Microbial Disease

F Frost PhD, T Kunde MPH, L Harter PhD, T Muller MS, GF Craun PE MPH, RL Calderon MPH PhD

ABSTRACT

Context: The effectiveness of current drinking...

Current Issues in Research on Intelligence. ERIC/AE Digest.

ERIC Educational Resources Information Center

Yekovich, Frank R.

Intelligence has been defined and studied under a number of different rubrics. Three individuals serve as a representative sample of the educational and psychological researchers associated with cognitive psychology who have made significant contributions to current understandings of intelligence. Robert Sternberg's theory contains subcategories…

Exploring the Recurrence of Contributing Area Dynamics

NASA Astrophysics Data System (ADS)

Spence, C.; Mengistu, S. G.

2015-12-01

Recent years have witnessed a progression towards using models as a tool for predicting high frequency contributing area dynamics in catchments. High frequency contributing area modeling can become a viable alternative to the current approach for estimating contributing area in Canadian catchments, which assumes a static portion of the catchment's gross drainage area. The current approach does not consider the spatiotemporal variability of contributing area dynamics, and therefore, represents an important challenge for characterizing the recurrence that saturated areas in the catchment can actively connect and contribute to the main channel in response to runoff producing snowmelt or storm events. Such characterizations are useful to assess the relative importance of different areas within a catchment for runoff generation, and nutrient production and transport. In this study, the PDMROF configuration of Environment Canada's MESH model has been applied to simulate areas actively contributing to daily streamflow from four nested catchments of the Qu'Appelle River basin. The return periods of annual maximum contributing areas were computed using Weibull's equation. The research also evaluates if runoff magnitude is always associated with the same extent and recurrence of contributing area and investigates how contributing area and streamflow return periods relate. This work provides the foundation for evaluating the effect of environmental changes (mainly land use and climate associated changes) on contributing area recurrence by conducting similar investigations under various environmental change scenarios.

The plasmasheet H+ and O+ contribution on the storm time ring current

NASA Astrophysics Data System (ADS)

Mouikis, C.; Bingham, S.; Kistler, L. M.; Spence, H. E.; Gkioulidou, M.; Claudepierre, S. G.; Farrugia, C. J.

2015-12-01

The source population of the storm time ring current is the night side plasma sheet. We use Van Allen Probes and Cluster observations to determine the contribution of the convecting plasma sheet H+ and O+ particles in the storm time development of the ring current. Using the Volland-Stern model with a dipole magnetic field together with the identification of the observed energy cutoffs in the particle spectra, we specify the pressure contributed by H+ and O+ populations that are on open drift paths vs. the pressure contributed by the trapped populations, for different local times. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L~2 and their pressure compares to the local magnetic field pressure as deep as L~3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current.

Na(+)/K(+) pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches.

PubMed

Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

2016-09-02

The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na(+)/K(+) pump current to such bursting activity has not been well studied. We used monensin, a Na(+)/H(+) antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs(+). The decreased period could also occur if the pump was inhibited with strophanthidin or K(+)-free saline. Our monensin results were reproduced in model, which explains the pump's contributions to bursting activity based on Na(+) dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks.

Current drive by helicon waves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul, Manash Kumar; Bora, Dhiraj; ITER Organization, Cadarache Centre-building 519, 131008 St. Paul-Lez-Durance

2009-01-01

Helicity in the dynamo field components of helicon wave is examined during the novel study of wave induced helicity current drive. Strong poloidal asymmetry in the wave magnetic field components is observed during helicon discharges formed in a toroidal vacuum chamber of small aspect ratio. High frequency regime is chosen to increase the phase velocity of helicon waves which in turn minimizes the resonant wave-particle interactions and enhances the contribution of the nonresonant current drive mechanisms. Owing to the strong poloidal asymmetry in the wave magnetic field structures, plasma current is driven mostly by the dynamo-electric-field, which arise due tomore » the wave helicity injection by helicon waves. Small, yet finite contribution from the suppressed wave-particle resonance cannot be ruled out in the operational regime examined. A brief discussion on the parametric dependence of plasma current along with numerical estimations of nonresonant components is presented. A close agreement between the numerical estimation and measured plasma current magnitude is obtained during the present investigation.« less

Multilevel Exploration of Factors Contributing to the Overrepresentation of Black Students in Office Disciplinary Referrals

ERIC Educational Resources Information Center

Bradshaw, Catherine P.; Mitchell, Mary M.; O'Brennan, Lindsey M.; Leaf, Philip J.

2010-01-01

Although there is increasing awareness of the overrepresentation of ethic minority students--particularly Black students--in disciplinary actions, the extant research has rarely empirically examined potential factors that may contribute to these disparities. The current study used a multilevel modeling approach to examine factors at the child…

Clinical Supervision Model in Teaching Practice: Does It Make a Difference in Supervisors' Performance?

ERIC Educational Resources Information Center

Gürsoy, Esim; Kesner, John Edward; Salihoglu, Umut Muharrem

2016-01-01

In search for better practices there has been a plethora of research in preservice teacher training. To contribute to the literature, the current study aims at investigating teacher trainees' and cooperating teachers' views about the performance and contribution of supervisors during teaching practice after using Clinical Supervision Model.…

Nonsuicidal Self-Injury in College Students: The Role of Perfectionism and Rumination

ERIC Educational Resources Information Center

Hoff, Erica R.; Muehlenkamp, Jennifer J.

2009-01-01

A paucity of research exists examining personality and cognitive characteristics that may contribute to nonsuicidal self-injury (NSSI). The purpose of the current study was to clarify the contribution of perfectionism and rumination, along with depression and anxiety, to NSSI within a sample of 170 college students. Group comparisons revealed that…

Cognate Awareness in French Immersion Students: Contributions to Grade 2 Reading Comprehension

ERIC Educational Resources Information Center

Hipfner-Boucher, Kathleen; Pasquarella, Adrian; Chen, Xi; Deacon, S. Hélène

2016-01-01

Cognate awareness is the ability to recognize the cognate relationship between words in two etymologically related languages. The current study examined the development of cognate awareness and its contribution to French (second language) reading comprehension among Canadian French immersion children. Eighty-one students were tested at the end of…

Note on the helicity decomposition of spin and orbital optical currents

NASA Astrophysics Data System (ADS)

Aiello, Andrea; Berry, M. V.

2015-06-01

In the helicity representation, the Poynting vector (current) for a monochromatic optical field, when calculated using either the electric or the magnetic field, separates into right-handed and left-handed contributions, with no cross-helicity contributions. Cross-helicity terms do appear in the orbital and spin contributions to the current. But when the electric and magnetic formulas are averaged (‘electric-magnetic democracy’), these terms cancel, restoring the separation into right-handed and left-handed currents for orbital and spin separately.

Estimating the relative contributions of maternal genetic, paternal genetic and intrauterine factors to offspring birth weight and head circumference

PubMed Central

Rice, Frances; Thapar, Anita

2010-01-01

Background Genetic factors and the prenatal environment contribute to birth weight. However, very few types of study design can disentangle their relative contribution. Aims To examine maternal genetic and intrauterine contributions to offspring birth weight and head circumference. To compare the contribution of maternal and paternal genetic effects. Study design Mothers and fathers were either genetically related or unrelated to their offspring who had been conceived by in vitro fertilization. Subjects 423 singleton full term offspring, of whom 262 were conceived via homologous IVF (both parents related), 66 via sperm donation (mother only related) and 95 via egg donation (father only related). Measures Maternal weight at antenatal booking, current weight and maternal height. Paternal current weight and height were all predictors. Infant birth weight and head circumference were outcomes. Results Genetic relatedness was the main contributing factor between measures of parental weight and offspring birth weight as correlations were only significant when the parent was related to the child. However, there was a contribution of the intrauterine environment to the association between maternal height and both infant birth weight and infant head circumference as these were significant even when mothers were unrelated to their child. Conclusions Both maternal and paternal genes made contributions to infant birth weight. Maternal height appeared to index a contribution of the intrauterine environment to infant growth and gestational age. Results suggested a possible biological interaction between the intrauterine environment and maternal inherited characteristics which suppresses the influence of paternal genes. PMID:20646882

The Contribution of Phonological Awareness to Reading Fluency and Its Individual Sub-skills in Readers Aged 9- to 12-years

PubMed Central

Elhassan, Zena; Crewther, Sheila G.; Bavin, Edith L.

2017-01-01

Research examining phonological awareness (PA) contributions to reading in established readers of different skill levels is limited. The current study examined the contribution of PA to phonological decoding, visual word recognition, reading rate, and reading comprehension in 124 fourth to sixth grade children (aged 9–12 years). On the basis of scores on the FastaReada measure of reading fluency participants were allocated to one of three reading ability categories: dysfluent (n = 47), moderate (n = 38) and fluent (n = 39). For the dysfluent group, PA contributed significantly to all reading measures except rate, but in the moderate group only to phonological decoding. PA did not influence performances on any of the reading measures examined for the fluent reader group. The results support the notion that fluency is characterized by a shift from conscious decoding to rapid and accurate visual recognition of words. Although PA may be influential in reading development, the results of the current study show that it is not sufficient for fluent reading. PMID:28443048

The Contribution of Phonological Awareness to Reading Fluency and Its Individual Sub-skills in Readers Aged 9- to 12-years.

PubMed

Elhassan, Zena; Crewther, Sheila G; Bavin, Edith L

2017-01-01

Research examining phonological awareness (PA) contributions to reading in established readers of different skill levels is limited. The current study examined the contribution of PA to phonological decoding, visual word recognition, reading rate, and reading comprehension in 124 fourth to sixth grade children (aged 9-12 years). On the basis of scores on the FastaReada measure of reading fluency participants were allocated to one of three reading ability categories: dysfluent ( n = 47), moderate ( n = 38) and fluent ( n = 39). For the dysfluent group, PA contributed significantly to all reading measures except rate, but in the moderate group only to phonological decoding. PA did not influence performances on any of the reading measures examined for the fluent reader group. The results support the notion that fluency is characterized by a shift from conscious decoding to rapid and accurate visual recognition of words. Although PA may be influential in reading development, the results of the current study show that it is not sufficient for fluent reading.

Dynamics of Internal Tides Over a Shallow Ridge Investigated With a High-Resolution Downscaling Regional Ocean Model

NASA Astrophysics Data System (ADS)

Masunaga, Eiji; Uchiyama, Yusuke; Suzue, Yota; Yamazaki, Hidekatsu

2018-04-01

This study investigates the dynamics of tidally induced internal waves over a shallow ridge, the Izu-Ogasawara Ridge off the Japanese mainland, using a downscaled high-resolution regional ocean numerical model. Both the Kuroshio and tides contribute to the field of currents in the study area. The model results show strong internal tidal energy fluxes over the ridge, exceeding 3.5 kW m-1, which are higher than the fluxes along the Japanese mainland. The flux in the upstream side of the Kuroshio is enhanced by an interaction of internal waves and currents. The tidal forcing induces 92% of the total internal wave energy flux, exhibiting the considerable dominance of tides in internal waves. The tidal forcing enhances the kinetic energy, particularly in the northern area of the ridge where the Kuroshio Current is not a direct influence. The tidal forcing contributes to roughly 30% of the total kinetic energy in the study area.

Supporting Academic Persistence in Low-Skilled Adult Learners

ERIC Educational Resources Information Center

O'Neill, Susan; Thomson, Margareta Maria

2013-01-01

The current literature review explores the factors that contribute to academic persistence for adult learners. The aim of the study is to identify current research-based strategies aimed at supporting learner persistence, particularly for low-skilled adults. Elements of three theoretical frameworks, namely, expectancy-value theory (EVT), goal…

Casimir effect and graphene: Tunability, scalability, Casimir rotor

NASA Astrophysics Data System (ADS)

Martinez, J. C.; Chen, X.; Jalil, M. B. A.

2018-01-01

We study the combined effects of separated parallel disks, birefringence and surface currents on the Casimir force and torque. All three contribute to the Casimir force and surface currents from graphene permit tuning and switching from attraction to repulsion thus allowing for an oscillating Casimir force which can be relevant to parametric amplification applications. Only the latter two contribute to the Casimir torque and their combined effect can enhance the torque by at least tenfold (possibly more) compared to that due to birefringence alone, a hint at a scalable Casimir torque. We also consider a feasible non-contact rotor.

Thermally Stimulated Currents in Nanocrystalline Titania

PubMed Central

Bruzzi, Mara; Mori, Riccardo; Baldi, Andrea; Cavallaro, Alessandro; Scaringella, Monica

2018-01-01

A thorough study on the distribution of defect-related active energy levels has been performed on nanocrystalline TiO2. Films have been deposited on thick-alumina printed circuit boards equipped with electrical contacts, heater and temperature sensors, to carry out a detailed thermally stimulated currents analysis on a wide temperature range (5–630 K), in view to evidence contributions from shallow to deep energy levels within the gap. Data have been processed by numerically modelling electrical transport. The model considers both free and hopping contribution to conduction, a density of states characterized by an exponential tail of localized states below the conduction band and the convolution of standard Thermally Stimulated Currents (TSC) emissions with gaussian distributions to take into account the variability in energy due to local perturbations in the highly disordered network. Results show that in the low temperature range, up to 200 K, hopping within the exponential band tail represents the main contribution to electrical conduction. Above room temperature, electrical conduction is dominated by free carriers contribution and by emissions from deep energy levels, with a defect density ranging within 1014–1018 cm−3, associated with physio- and chemi-sorbed water vapour, OH groups and to oxygen vacancies. PMID:29303976

Thermally Stimulated Currents in Nanocrystalline Titania.

PubMed

Bruzzi, Mara; Mori, Riccardo; Baldi, Andrea; Carnevale, Ennio Antonio; Cavallaro, Alessandro; Scaringella, Monica

2018-01-05

A thorough study on the distribution of defect-related active energy levels has been performed on nanocrystalline TiO₂. Films have been deposited on thick-alumina printed circuit boards equipped with electrical contacts, heater and temperature sensors, to carry out a detailed thermally stimulated currents analysis on a wide temperature range (5-630 K), in view to evidence contributions from shallow to deep energy levels within the gap. Data have been processed by numerically modelling electrical transport. The model considers both free and hopping contribution to conduction, a density of states characterized by an exponential tail of localized states below the conduction band and the convolution of standard Thermally Stimulated Currents (TSC) emissions with gaussian distributions to take into account the variability in energy due to local perturbations in the highly disordered network. Results show that in the low temperature range, up to 200 K, hopping within the exponential band tail represents the main contribution to electrical conduction. Above room temperature, electrical conduction is dominated by free carriers contribution and by emissions from deep energy levels, with a defect density ranging within 10 14 -10 18 cm -3 , associated with physio- and chemi-sorbed water vapour, OH groups and to oxygen vacancies.

Factors Contributing to Regular Smoking in Adolescents in Turkey

ERIC Educational Resources Information Center

Can, Gamze; Topbas, Murat; Oztuna, Funda; Ozgun, Sukru; Can, Emine; Yavuzyilmaz, Asuman

2009-01-01

Purpose: The objectives of this study were to determine the levels of lifetime cigarette use, daily use, and current use among young people (aged 15-19 years) and to examine the risk factors contributing to regular smoking. Methods: The number of students was determined proportionately to the numbers of students in all the high schools in the…

Exploring the Relationship between Time Management Skills and the Academic Achievement of African Engineering Students--A Case Study

ERIC Educational Resources Information Center

Swart, Arthur James; Lombard, Kobus; de Jager, Henk

2010-01-01

Poor academic success by African engineering students is currently experienced in many higher educational institutions, contributing to lower financial subsidies by local governments. One of the contributing factors to this low academic success may be the poor time management skills of these students. This article endeavours to explore this…

The "Responsive Classroom" Approach and Fifth Grade Students' Math and Science Anxiety and Self-Efficacy

ERIC Educational Resources Information Center

Griggs, Marissa Swaim; Rimm-Kaufman, Sara E.; Merritt, Eileen G.; Patton, Christine L.

2013-01-01

Self-efficacy forecasts student persistence and achievement in challenging subjects. Thus, it is important to understand factors that contribute to students' self-efficacy, a key factor in their success in math and science. The current cross-sectional study examined the contribution of students' gender and math and science anxiety as well as…

Individual Differences in the Development of Early Writing Skills: Testing the Unique Contribution of Visuo-Spatial Working Memory

ERIC Educational Resources Information Center

Bourke, Lorna; Davies, Simon J.; Sumner, Emma; Green, Carolyn

2014-01-01

Visually mediated processes including, exposure to print (e.g. reading) as well as orthographic transcription and coding skills, have been found to contribute to individual differences in literacy development. The current study examined the role of visuospatial working memory (WM) in underpinning this relationship and emergent writing. One hundred…

Socio-Ecological Factors Affecting Pregnant Women's Anemia Status in Freetown, Sierra Leone

ERIC Educational Resources Information Center

M'Cormack, Fredanna; Drolet, Judy

2012-01-01

Background: Sierra Leone has high maternal mortality. Socio-ecological factors are considered contributing factors to this high mortality. Anemia is considered to be a direct cause of 4% of maternal deaths and an indirect cause of 20-40% of maternal deaths. Purpose: The current study explores socio-ecological contributing factors to the anemia…

Development of Infant Positive Emotionality: The Contribution of Maternal Characteristics and Effects on Subsequent Parenting

ERIC Educational Resources Information Center

Bridgett, David J.; Laake, Lauren M.; Gartstein, Maria A.; Dorn, Danielle

2013-01-01

The current study examined the influence of maternal characteristics on the development of infant smiling and laughter, a marker of early positive emotionality (PE) and how maternal characteristics and the development of infant PE contributed to subsequent maternal parenting. One hundred fifty-nine mothers with 4-month-old infants participated.…

Classroom Walkthroughs: Does Such an Approach to Supervision Contribute to District Improvement?

ERIC Educational Resources Information Center

Fields, Cary

2013-01-01

The purpose of this study was to examine what types of data collection currently exist and what kind of information should be provided through a walkthrough observation process that attempts to enhance teaching practice, contribute to student learning and assist a district's overall improvement planning. In fulfilling this purpose the…

The Contributions of Human Resource Development Research across Disciplines: A Citation and Content Analysis

ERIC Educational Resources Information Center

Jeung, Chang-Wook; Yoon, Hea Jun; Park, Sunyoung; Jo, Sung Jun

2011-01-01

The primary purpose of the current study is to identify how human resource development (HRD) research has contributed to the knowledge base across social science disciplines during the past two decades. We identified the top 20 Academy of Human Resource Development (AHRD) journal articles that have been most frequently cited in research articles…

Probing Lexical Representations: Simultaneous Modeling of Word and Reader Contributions to Multidimensional Lexical Representations

ERIC Educational Resources Information Center

Goodwin, Amanda P.; Gilbert, Jennifer K.; Cho, Sun-Joo; Kearns, Devin M.

2014-01-01

The current study models reader, item, and word contributions to the lexical representations of 39 morphologically complex words for 172 middle school students using a crossed random-effects item response model with multiple outcomes. We report 3 findings. First, results suggest that lexical representations can be characterized by separate but…

Current and emerging concepts in muscle tension dysphonia: a 30-month review.

PubMed

Altman, Kenneth W; Atkinson, Cory; Lazarus, Cathy

2005-06-01

The modern theory of hoarseness is that there are multifactorial etiologies contributing to the voice problem. The hypothesis of this study is that muscle tension dysphonia is multifactorial with various contributing etiologies. This project is a retrospective chart review of all patients seen in the Voice Speech and Language Service and Swallowing Center at our institution with a diagnosis of muscle tension (functional hypertensive) dysphonia over a 30-month period. A literature search and review is also performed regarding current and emerging concepts of muscle tension dysphonia. One hundred fifty subjects were identified (60% female, 40% male, with a mean age of 42.3 years). Significant factors in patient history believed to contribute to abnormal voice production were gastroesophageal reflux in 49%, high stress levels in 18%, excessive amounts of voice use in 63%, and excessive loudness demands on voice use in 23%. Otolaryngologic evaluation was performed in 82% of patients, in whom lesions, significant vocal fold edema, or paralysis/paresis was identified in 52.3%. Speech pathology assessment revealed poor breath support, inappropriately low pitch, and visible cervical neck tension in the majority of patients. Inappropriate intensity was observed in 23.3% of patients. This set of multiple contributing factors is discussed in the context of current and emerging understanding of muscle tension dysphonia. Results confirm multifactorial etiologies contributing to hoarseness in the patients identified with muscle tension dysphonia. An interdisciplinary approach to treating all contributing factors portends the best prognosis.

Development of an on-line source-tagged model for sulfate, nitrate and ammonium: A modeling study for highly polluted periods in Shanghai, China.

PubMed

Wu, Jian-Bin; Wang, Zifa; Wang, Qian; Li, Jie; Xu, Jianming; Chen, HuanSheng; Ge, Baozhu; Zhou, Guangqiang; Chang, Luyu

2017-02-01

An on-line source-tagged model coupled with an air quality model (Nested Air Quality Prediction Model System, NAQPMS) was applied to estimate source contributions of primary and secondary sulfate, nitrate and ammonium (SNA) during a representative winter period in Shanghai. This source-tagged model system could simultaneously track spatial and temporal sources of SNA, which were apportioned to their respective primary precursors in a simulation run. The results indicate that in the study period, local emissions in Shanghai accounted for over 20% of SNA contributions and that Jiangsu and Shandong were the two major non-local sources. In particular, non-local emissions had higher contributions during recorded pollution periods. This suggests that the transportation of pollutants plays a key role in air pollution in Shanghai. The temporal contributions show that the emissions from the "current day" (emission contribution from the current day during which the model was simulating) contributed 60%-70% of the sulfate and ammonium concentrations but only 10%-20% of the nitrate concentration, while the previous days' contributions increased during the recorded pollution periods. Emissions that were released within three days contributed over 85% averagely for SNA in January 2013. To evaluate the source-tagged model system, the results were compared by sensitivity analysis (emission perturbation of -30%) and backward trajectory analysis. The consistency of the comparison results indicated that the source-tagged model system can track sources of SNA with reasonable accuracy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Low frequency noise in p-InAsSbP/n-InAs infrared photodiodes

NASA Astrophysics Data System (ADS)

Dyakonova, N.; Karandashev, S. A.; Levinshtein, M. E.; Matveev, B. A.; Remennyi, M. A.

2018-06-01

We report the first experimental study of low-frequency noise in p-InAsSbP/n-InAs infrared photodiodes. For forward bias, experiments have been carried out at 300 and 77 K, in the photovoltaic regime the measurements have been done at 300 K. At room temperature the current noise spectral density, SI , exhibits the ∼1/f frequency dependence. For low currents, I ≤ I 0 ∼ 4 × 10‑5 A, S I is proportional to I 2, at higher currents this dependence changes to S I ∼ I. At 77 K the noise spectral density is significantly higher than at 300 K, and Lorentzian contributions to noise are observed. The current dependences of spectral noise density can be approximately described as S I ∼ I 1.5 and show particularities suggesting the contribution of defects.

Executing a gather operation on a parallel computer

DOEpatents

Archer, Charles J [Rochester, MN; Ratterman, Joseph D [Rochester, MN

2012-03-20

Methods, apparatus, and computer program products are disclosed for executing a gather operation on a parallel computer according to embodiments of the present invention. Embodiments include configuring, by the logical root, a result buffer or the logical root, the result buffer having positions, each position corresponding to a ranked node in the operational group and for storing contribution data gathered from that ranked node. Embodiments also include repeatedly for each position in the result buffer: determining, by each compute node of an operational group, whether the current position in the result buffer corresponds with the rank of the compute node, if the current position in the result buffer corresponds with the rank of the compute node, contributing, by that compute node, the compute node's contribution data, if the current position in the result buffer does not correspond with the rank of the compute node, contributing, by that compute node, a value of zero for the contribution data, and storing, by the logical root in the current position in the result buffer, results of a bitwise OR operation of all the contribution data by all compute nodes of the operational group for the current position, the results received through the global combining network.

Advanced electric propulsion research - 1990

NASA Technical Reports Server (NTRS)

Monheiser, Jeffery M.; Wilbur, Paul J.

1991-01-01

An experimental study of impingement current collection on the accelerator grid of an ion thruster is presented. The equipment, instruments, and procedures being used to conduct the study are discussed. The contribution to this current due to charge-exchange ions produced close to the grid is determined using a volume-integration procedure and measured ion beam current design, computed neutral atom density and measured beam plasma potential data. This current, which is expected to be almost equal to that measured directly, is found to be an order of magnitude less. The impingement current determined by integrating the current density of ambient ions in the beam plasma close to the grid is found to agree with the directly measured impingement current. Possible reasons for the disagreement between the directly measured and volume integrated impingement currents are discussed.

Characterization of the amino acid contribution to the folding degree of proteins.

PubMed

Estrada, Ernesto

2004-03-01

The folding degree index (Estrada, Bioinformatics 2002;18:697-704) is extended to account for the contribution of amino acids to folding. First, the mathematical formalism for extending the folding degree index is presented. Then, the amino acid contributions to folding degree of several proteins are used to analyze its relation to secondary structure. The possibilities of using these contributions in helping or checking the assignation of secondary structure to amino acids are also introduced. The influence of external factors to the amino acids contribution to folding degree is studied through the temperature effect on ribonuclease A. Finally, the analysis of 3D protein similarity through the use of amino acid contributions to folding degree is studied by selecting a series of lysozymes. These results are compared to that obtained by sequence alignment (2D similarity) and 3D superposition of the structures, showing the uniqueness of the current approach. Copyright 2004 Wiley-Liss, Inc.

Decreased voltage-gated potassium currents in rat dorsal root ganglion neurons after chronic constriction injury.

PubMed

Xiao, Yun; Wu, Yang; Zhao, Bo; Xia, Zhongyuan

2016-01-20

Voltage-gated potassium channels (KV) regulate pain transmission by controlling neuronal excitability. Changes in KV expression patterns may thus contribute toward hyperalgesia following nerve injury. The aim of this study was to characterize KV current density in dorsal root ganglion (DRG) neurons following chronic constriction injury (CCI) of the right sciatic nerve, a robust model of post-traumatic neuropathic pain. The study examined changes in small-diameter potassium ion currents (<30 µm) in neurons in the L4-L6 DRG following CCI by whole-cell patch-clamping and the association with post-CCI mechanical and thermal nociceptive thresholds. Compared with the control group, 7 days after CCI, the mechanical force and temperature required to elicit ipsilateral foot withdrawal decreased significantly, indicating tactile allodynia and thermal hyperalgesia. Post-CCI neurons had a significantly lower rheobase current and depolarized resting membrane potential than controls, suggesting KV current downregulation. Some ipsilateral DRG neurons also had spontaneous action potentials and repetitive firing. There was a 55% reduction in the total KV current density caused by a 55% decrease in the sustained delayed rectifier potassium ion current (IK) density and a 17% decrease in the transient A-type potassium ion current (IA) density. These results indicated that changes in DRG neuron IK and IA current density and concomitant afferent hyperexcitability may contribute toward neuropathic pain following injury. The rat CCI model may prove valuable for examining pathogenic mechanisms and potential therapies, such as KV channel modulators.

Turbulent current drive mechanisms

NASA Astrophysics Data System (ADS)

McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

2017-08-01

Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm's law and hence provide an ideal means for driving deviations from neoclassical predictions.

Na+/K+ pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches

PubMed Central

Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

2016-01-01

The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na+/K+ pump current to such bursting activity has not been well studied. We used monensin, a Na+/H+ antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs+. The decreased period could also occur if the pump was inhibited with strophanthidin or K+-free saline. Our monensin results were reproduced in model, which explains the pump’s contributions to bursting activity based on Na+ dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks. DOI: http://dx.doi.org/10.7554/eLife.19322.001 PMID:27588351

Contribution For Arc Temperature Affected By Current Increment Ratio At Peak Current In Pulsed Arc

NASA Astrophysics Data System (ADS)

Kano, Ryota; Mitubori, Hironori; Iwao, Toru

2015-11-01

Tungsten Inert Gas (TIG) Welding is one of the high quality welding. However, parameters of the pulsed arc welding are many and complicated. if the welding parameters are not appropriate, the welding pool shape becomes wide and shallow.the convection of driving force contributes to the welding pool shape. However, in the case of changing current waveform as the pulse high frequency TIG welding, the arc temperature does not follow the change of the current. Other result of the calculation, in particular, the arc temperature at the reaching time of peak current is based on these considerations. Thus, the accurate measurement of the temperature at the time is required. Therefore, the objective of this research is the elucidation of contribution for arc temperature affected by current increment ratio at peak current in pulsed arc. It should obtain a detail knowledge of the welding model in pulsed arc. The temperature in the case of increment of the peak current from the base current is measured by using spectroscopy. As a result, when the arc current increases from 100 A to 150 A at 120 ms, the transient response of the temperature didn't occur during increasing current. Thus, during the current rise, it has been verified by measuring. Therefore, the contribution for arc temperature affected by current increment ratio at peak current in pulsed arc was elucidated in order to obtain more knowledge of welding model of pulsed arc.

The Contribution of Phonological and Morphological Awareness in Chinese-English Bilingual Reading Acquisition

ERIC Educational Resources Information Center

Lin, Candise Y.; Cheng, Chenxi; Wang, Min

2018-01-01

The current study examined the contribution of cross-language phonological and morphological awareness to reading acquisition in bilingual children. Participants were 140 children (M[subscript age] = 8.26 years) between Grades 1-4 who learned Chinese as their first language and English as their second language. Awareness of phoneme, onset-rime,…

Contribution of Personality to Self-Efficacy and Outcome Expectations in Selecting a High School Major among Adolescents with Learning Disabilities

ERIC Educational Resources Information Center

Brown, Dikla; Cinamon, Rachel Gali

2016-01-01

The current study focuses on the contribution of five personality traits to the development of self-efficacy and outcome expectations regarding selecting a high school major among adolescents with learning disabilities (LD). Social cognitive career theory and the Big Five personality traits model served as the theoretical framework. Participants…

Role-Playing Games for Capacity Building in Water and Land Management: Some Brazilian Experiences

ERIC Educational Resources Information Center

Camargo, Maria Eugenia; Jacobi, Pedro Roberto; Ducrot, Raphaele

2007-01-01

Role-playing games in natural resource management are currently being tested as research, training, and intervention tools all over the world. Various studies point out their potential to deal with complex issues and to contribute to training processes. The objective of this contribution is to analyze the limits and potentialities of this tool for…

The O+ contribution and role on the ring current pressure development for CMEs and CIRs using Van Allen Probes observations

NASA Astrophysics Data System (ADS)

Mouikis, C.; Bingham, S.; Kistler, L. M.; Farrugia, C. J.; Spence, H. E.; Gkioulidou, M.

2016-12-01

The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CME's), co-rotating interaction regions (CIR's), high-speed streamers and other structures. The resulting changes in the ring current particle pressure change the global magnetic field, which affects the transport of the radiation belts. In order to determine the field changes during a storm, it is necessary to understand the transport, sources and losses of the particles that contribute to the ring current. The source population of the storm time ring current is the night side plasma sheet. We use Van Allen Probes observations to determine the ring current pressure contribution of the convecting plasma sheet H+ and O+ particles in the storm time development of the ring current. We compare storms that are related to different interplanetary drivers, CMEs and CIRs, as observed at different local times. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L 2 and their pressure compares to the local magnetic field pressure as deep as L 3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current. However, the largest difference between the CME and CIR ring current responses during the storm main and early recovery phases is caused by how the 15 - 60 keV O+ responds to these drivers.

Studies of Polar Current Systems Using the IMS Scandinavian Magnetometer Array

NASA Astrophysics Data System (ADS)

Untiedt, J.; Baumjohann, W.

1993-09-01

As a contribution to the International Magnetospheric Study (IMS, 1976 1979) a two-dimensional array of 42 temporary magnetometer stations was run in Scandinavia, supplementary to the permanent observatories and concentrated in the northern part of the region. This effort aimed at the time-dependent (periods above about 100 s) determination of the two-dimensional structure of substorm-related magnetic fields at the Earth's surface with highest reasonable spatial resolution (about 100 km, corresponding to the height of the ionosphere) near the footpoints of field-aligned electric currents that couple the disturbed magnetosphere to the ionosphere at auroral latitudes. It has been of particular advantage for cooperative studies that not only simultaneous data were available from all-sky cameras, riometers, balloons, rockets, and satellites, but also from the STARE radar facility yielding colocated two-dimensional ionospheric electric field distributions. In many cases it therefore was possible to infer the three-dimensional regional structure of substorm-related ionospheric current systems. The first part of this review outlines the basic relationships and methods that have been used or have been developed for such studies. The second short part presents typical equivalent current patterns observed by the magnetometer array in the course of substorms. Finally we review main results of studies that have been based on the magnetometer array observations and on additional data, omitting studies on geomagnetic pulsations. These studies contributed to a clarification of the nature of auroral electrojets including the Harang discontinuity and of ionospheric current systems related to auroral features such as the break-up at midnight, the westward traveling surge, eastward drifting omega bands, and spirals.

The contribution of TWIK-1 channels to astrocyte K+ current is limited by retention in intracellular compartments

PubMed Central

Wang, Wei; Putra, Adhytia; Schools, Gary P.; Ma, Baofeng; Chen, Haijun; Kaczmarek, Leonard K.; Barhanin, Jacques; Lesage, Florian; Zhou, Min

2013-01-01

TWIK-1 two-pore domain K+ channels are expressed abundantly in astrocytes. In the present study, we examined the extent to which TWIK-1 contributes to the linear current-voltage (I–V) relationship (passive) K+ membrane conductance, a dominant electrophysiological feature of mature hippocampal astrocytes. Astrocytes from TWIK-1 knockout mice have a more negative resting potential than those from wild type animals and a reduction in both inward rectification and Cs+ permeability. Nevertheless, the overall whole-cell passive conductance is not altered significantly in TWIK-1 knockout astrocytes. The expression of Kir4.1 and TREK-1, two other major astrocytic K+ channels, or of other two-pore K+ channels is not altered in TWIK-1 knockout mice, suggesting that the mild effect of TWIK-1 knockout does not result from compensation by these channels. Fractionation experiments showed that TWIK-1 is primarily localized in intracellular cytoplasmic fractions (55%) and mildly hydrophobic internal compartment fractions (41%), with only 5% in fractions containing plasma membranes. Our study revealed that TWIK-1 proteins are mainly located in the intracellular compartments of hippocampal astrocyte under physiological condition, therefore a minimal contribution of TWIK-1 channels to whole-cell currents is likely attributable to a relatively low level presence of channels in the plasma membrane. PMID:24368895

Nonhuman Primate Models of Hepatitis A Virus and Hepatitis E Virus Infections.

PubMed

Lanford, Robert E; Walker, Christopher M; Lemon, Stanley M

2018-04-23

Although phylogenetically unrelated, human hepatitis viruses share an exclusive or near exclusive tropism for replication in differentiated hepatocytes. This narrow tissue tropism may contribute to the restriction of the host ranges of these viruses to relatively few host species, mostly nonhuman primates. Nonhuman primate models thus figure prominently in our current understanding of the replication and pathogenesis of these viruses, including the enterically transmitted hepatitis A virus (HAV) and hepatitis E virus (HEV), and have also played major roles in vaccine development. This review draws comparisons of HAV and HEV infection from studies conducted in nonhuman primates, and describes how such studies have contributed to our current understanding of the biology of these viruses. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

The enigmatic figure of Dr Henry Maudsley (1835-1918).

PubMed

Pantelidou, Maria; Demetriades, Andreas K

2014-08-01

In spite of his contribution to psychiatry in 19th century Britain, Henry Maudsley remains a mysterious figure, a man mostly known for his donation to the London County Council for the building of the Maudsley Hospital and for The Maudsley Annual Lecture created in honour of his benevolence. Besides Sir Aubrey Lewis' article in 1951 and Michael Collie's attempt in 1988 to construct a biographical study on Maudsley, there does not seem to be any current endeavour to tell the story of his life, whereas Trevor Turner's contribution to the 2004 Oxford Dictionary of National Biography gives a somewhat scathing but unattributed account of Maudsley's personality. This essay attempts to explore his contributions to the Medico-Psychological Association (MPA), the current Royal College of Psychiatrists, his editorship of the Journal of Mental Health (currently named the British Journal of Psychiatry), his literary contributions and his vision for a psychiatric hospital. This essay is an attempt to demystify his figure and to explore some of the rumours and criticisms surrounding his name and the reasons why so little has been written about him. It is also a venture to unravel his complex personality and his intricate philosophy. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Contribution of Sudanese medical diaspora to the healthcare delivery system in Sudan: exploring options and barriers.

PubMed

Abdalla, Fayrouz Mohammed; Omar, Maye Abu; Badr, Elsheikh Elsiddig

2016-06-30

Medical diaspora options, including the engagement of expatriate physicians in development efforts within their home country, are being called for to reverse the effects of brain drain from developing countries. This paper presents the results of a study exploring the potential contributions for the Sudanese Medial Diaspora Options to the healthcare delivery system (HCDS) in Sudan, focusing on the options of temporal and permanent returns and the likely obstacles faced in their implementation. This was a cross-sectional study using a mixed methods design including quantitative and qualitative approaches. For the quantitative approach, the study, which focused on the possible contribution of the diaspora to healthcare delivery in Sudan, was based on an online survey using random purposive and snowballing sampling techniques involving 153 Sudanese physicians working in Saudi Arabia and other Gulf States, the United Kingdom, the Republic of Ireland, and the United States of America. The qualitative approach involved in-depth interviews with returnee physicians and key informants in Sudan, focusing on the return experiences, the barriers for return, and the options to improve future contributions. Despite contributions of the Sudanese medical diaspora being of a small scale considering the size of the phenomenon, as well as infrequent and not appropriately organized, their inputs to academia and the links built with overseas institutions and specialist clinical services were nevertheless remarkable. The main barrier to temporal return was inappropriate organization by the local counterparts, while those for permanent return of physicians were poor work environment, insufficient financial payment, unsecured accommodation, and offspring education. The study identified short-term return as a feasible option considering the country's current conditions. Proper coordination mechanisms for short-term returns and facilitation of permanent return through stakeholders' collaboration were proposed to improve diaspora contributions. The potentials of Sudanese medial diaspora contributions to the HCDS in Sudan are promising. Short-term contributions were observed as the best option for the current country situation. Creation of a coordinating body from within the healthcare sector in Sudan to effectively coordinate diaspora contributions is recommended.

An Exploration of Pre-Service Teachers' Experiences in Outdoor "Places" and Intentions for Teaching in the Outdoors

ERIC Educational Resources Information Center

Blatt, Erica; Patrick, Patricia

2014-01-01

This study explores pre-service teachers' past interactions with "place" in outdoor settings and how these experiences contribute to their current perceptions of the importance of taking their own students into the outdoors. Specifically, the researchers were interested in investigating if current pre-service teachers are part of the…

Estimating the relative contributions of maternal genetic, paternal genetic and intrauterine factors to offspring birth weight and head circumference.

PubMed

Rice, Frances; Thapar, Anita

2010-07-01

Genetic factors and the prenatal environment contribute to birth weight. However, very few types of study design can disentangle their relative contribution. To examine maternal genetic and intrauterine contributions to offspring birth weight and head circumference. To compare the contribution of maternal and paternal genetic effects. Mothers and fathers were either genetically related or unrelated to their offspring who had been conceived by in vitro fertilization. 423 singleton full term offspring, of whom 262 were conceived via homologous IVF (both parents related), 66 via sperm donation (mother only related) and 95 via egg donation (father only related). Maternal weight at antenatal booking, current weight and maternal height. Paternal current weight and height were all predictors. Infant birth weight and head circumference were outcomes. Genetic relatedness was the main contributing factor between measures of parental weight and offspring birth weight as correlations were only significant when the parent was related to the child. However, there was a contribution of the intrauterine environment to the association between maternal height and both infant birth weight and infant head circumference as these were significant even when mothers were unrelated to their child. Both maternal and paternal genes made contributions to infant birth weight. Maternal height appeared to index a contribution of the intrauterine environment to infant growth and gestational age. Results suggested a possible biological interaction between the intrauterine environment and maternal inherited characteristics which suppresses the influence of paternal genes. 2010 Elsevier Ltd. All rights reserved.

Contributions of dopamine-related genes and environmental factors to highly sensitive personality: a multi-step neuronal system-level approach.

PubMed

Chen, Chunhui; Chen, Chuansheng; Moyzis, Robert; Stern, Hal; He, Qinghua; Li, He; Li, Jin; Zhu, Bi; Dong, Qi

2011-01-01

Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human personality has moderate to high heritability, but recent molecular behavioral genetic studies have failed to identify quantitative trait loci (QTL) with consistent effects. The current study adopted a multi-step approach (ANOVA followed by multiple regression and permutation) to assess the cumulative effects of multiple QTLs. Using a system-level (dopamine system) genetic approach, we investigated a personality trait deeply rooted in the nervous system (the Highly Sensitive Personality, HSP). 480 healthy Chinese college students were given the HSP scale and genotyped for 98 representative polymorphisms in all major dopamine neurotransmitter genes. In addition, two environment factors (stressful life events and parental warmth) that have been implicated for their contributions to personality development were included to investigate their relative contributions as compared to genetic factors. In Step 1, using ANOVA, we identified 10 polymorphisms that made statistically significant contributions to HSP. In Step 2, these polymorphism's main effects and interactions were assessed using multiple regression. This model accounted for 15% of the variance of HSP (p<0.001). Recent stressful life events accounted for an additional 2% of the variance. Finally, permutation analyses ascertained the probability of obtaining these findings by chance to be very low, p ranging from 0.001 to 0.006. Dividing these loci by the subsystems of dopamine synthesis, degradation/transport, receptor and modulation, we found that the modulation and receptor subsystems made the most significant contribution to HSP. The results of this study demonstrate the utility of a multi-step neuronal system-level approach in assessing genetic contributions to individual differences in human behavior. It can potentially bridge the gap between the high heritability estimates based on traditional behavioral genetics and the lack of reproducible genetic effects observed currently from molecular genetic studies.

Contributions of Dopamine-Related Genes and Environmental Factors to Highly Sensitive Personality: A Multi-Step Neuronal System-Level Approach

PubMed Central

Chen, Chunhui; Chen, Chuansheng; Moyzis, Robert; Stern, Hal; He, Qinghua; Li, He; Li, Jin; Zhu, Bi; Dong, Qi

2011-01-01

Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human personality has moderate to high heritability, but recent molecular behavioral genetic studies have failed to identify quantitative trait loci (QTL) with consistent effects. The current study adopted a multi-step approach (ANOVA followed by multiple regression and permutation) to assess the cumulative effects of multiple QTLs. Using a system-level (dopamine system) genetic approach, we investigated a personality trait deeply rooted in the nervous system (the Highly Sensitive Personality, HSP). 480 healthy Chinese college students were given the HSP scale and genotyped for 98 representative polymorphisms in all major dopamine neurotransmitter genes. In addition, two environment factors (stressful life events and parental warmth) that have been implicated for their contributions to personality development were included to investigate their relative contributions as compared to genetic factors. In Step 1, using ANOVA, we identified 10 polymorphisms that made statistically significant contributions to HSP. In Step 2, these polymorphism's main effects and interactions were assessed using multiple regression. This model accounted for 15% of the variance of HSP (p<0.001). Recent stressful life events accounted for an additional 2% of the variance. Finally, permutation analyses ascertained the probability of obtaining these findings by chance to be very low, p ranging from 0.001 to 0.006. Dividing these loci by the subsystems of dopamine synthesis, degradation/transport, receptor and modulation, we found that the modulation and receptor subsystems made the most significant contribution to HSP. The results of this study demonstrate the utility of a multi-step neuronal system-level approach in assessing genetic contributions to individual differences in human behavior. It can potentially bridge the gap between the high heritability estimates based on traditional behavioral genetics and the lack of reproducible genetic effects observed currently from molecular genetic studies. PMID:21765900

Turbulent current drive mechanisms

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm’s law, and hence provide an ideal means for driving deviationsmore » from neoclassical predictions.« less

Turbulent current drive mechanisms

DOE PAGES

McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

2017-07-01

Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm’s law, and hence provide an ideal means for driving deviationsmore » from neoclassical predictions.« less

Measuring the Contribution of Higher Education to Innovation Capacity in the EU. Final Report: Revised Version

ERIC Educational Resources Information Center

European Commission, 2017

2017-01-01

This current study is part of the actions taken aiming to analyse the links between the operations and effects of higher-education institutions on the capacity to innovate in the economies in Europe. Providing insights into the contribution of higher education to the innovative capacity of the EU economies is crucial for policy making and the…

Measuring the Contribution of Higher Education to Innovation Capacity in the EU. Executive Summary of the Final Report

ERIC Educational Resources Information Center

European Commission, 2017

2017-01-01

This current study is part of the actions taken aiming to analyse the links between the operations and effects of higher-education institutions on the capacity to innovate in the economies in Europe. Providing insights into the contribution of higher education to the innovative capacity of the EU economies is crucial for policy making and the…

Magnetic storm of September 4, 1984 - A synthesis of ring current spectra and energy densities measured with AMPTE/CCE

NASA Technical Reports Server (NTRS)

Krimigis, S. M.; Mcentire, R. W.; Potemra, T. A.; Gloeckler, G.; Scarf, F. L.; Shelley, E. G.

1985-01-01

Compositional studies of the equatorial distributions of ring current ions during the September 4, 1984 magnetic storm have been made possible by comprehensive energy, charge state, and mass coverage data from the Charge Composition Explorer satellite. An examination of ion spectra at an L value of about 4 on September 5, in the local evening sector, shows that energy density was dominated by protons, with O ions contributing about 27 percent at the peak of about 150 keV, while He ions contributed less than about 2 percent. September 6 ion spectra, taken during the recovery phase of the storm, indicate that ion densities at more than 20 keV had decreased markedly, and that the ring current energy density was primarily provided by protons.

Selective activation of heteromeric SK channels contributes to action potential repolarization in mouse atrial myocytes.

PubMed

Hancock, Jane M; Weatherall, Kate L; Choisy, Stéphanie C; James, Andrew F; Hancox, Jules C; Marrion, Neil V

2015-05-01

Activation of small conductance calcium-activated potassium (SK) channels is proposed to contribute to repolarization of the action potential in atrial myocytes. This role is controversial, as these cardiac SK channels appear to exhibit an uncharacteristic pharmacology. The objectives of this study were to resolve whether activation of SK channels contributes to atrial action potential repolarization and to determine the likely subunit composition of the channel. The effect of 2 SK channel inhibitors was assessed on outward current evoked in voltage clamp and on action potential duration in perforated patch and whole-cell current clamp recording from acutely isolated mouse atrial myocytes. The presence of SK channel subunits was assessed using immunocytochemistry. A significant component of outward current was reduced by the SK channel blockers apamin and UCL1684. Block by apamin displayed a sensitivity indicating that this current was carried by homomeric SK2 channels. Action potential duration was significantly prolonged by UCL1684, but not by apamin. This effect was accompanied by an increase in beat-to-beat variability and action potential triangulation. This pharmacology was matched by that of expressed heteromeric SK2-SK3 channels in HEK293 cells. Immunocytochemistry showed that atrial myocytes express both SK2 and SK3 channels with an overlapping expression pattern. Only proposed heteromeric SK2-SK3 channels are physiologically activated to contribute to action potential repolarization, which is indicated by the difference in pharmacology of evoked outward current and prolongation of atrial action potential duration. The effect of blocking this channel on the action potential suggests that SK channel inhibition during cardiac function has the potential to be proarrhythmic. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Effect of Inductive Coil Geometry and Current Sheet Trajectory of a Conical Theta Pinch Pulsed Inductive Plasma Accelerator

NASA Technical Reports Server (NTRS)

Hallock, Ashley K.; Polzin, Kurt A.; Bonds, Kevin W.; Emsellem, Gregory D.

2011-01-01

Results are presented demonstrating the e ect of inductive coil geometry and current sheet trajectory on the exhaust velocity of propellant in conical theta pinch pulsed induc- tive plasma accelerators. The electromagnetic coupling between the inductive coil of the accelerator and a plasma current sheet is simulated, substituting a conical copper frustum for the plasma. The variation of system inductance as a function of plasma position is obtained by displacing the simulated current sheet from the coil while measuring the total inductance of the coil. Four coils of differing geometries were employed, and the total inductance of each coil was measured as a function of the axial displacement of two sep- arate copper frusta both having the same cone angle and length as the coil but with one compressed to a smaller size relative to the coil. The measured relationship between total coil inductance and current sheet position closes a dynamical circuit model that is used to calculate the resulting current sheet velocity for various coil and current sheet con gura- tions. The results of this model, which neglects the pinching contribution to thrust, radial propellant con nement, and plume divergence, indicate that in a conical theta pinch ge- ometry current sheet pinching is detrimental to thruster performance, reducing the kinetic energy of the exhausting propellant by up to 50% (at the upper bound for the parameter range of the study). The decrease in exhaust velocity was larger for coils and simulated current sheets of smaller half cone angles. An upper bound for the pinching contribution to thrust is estimated for typical operating parameters. Measurements of coil inductance for three di erent current sheet pinching conditions are used to estimate the magnetic pressure as a function of current sheet radial compression. The gas-dynamic contribution to axial acceleration is also estimated and shown to not compensate for the decrease in axial electromagnetic acceleration that accompanies the radial compression of the plasma in conical theta pinches.

DEFINED CONTRIBUTION PLANS, DEFINED BENEFIT PLANS, AND THE ACCUMULATION OF RETIREMENT WEALTH

PubMed Central

Poterba, James; Rauh, Joshua; Venti, Steven; Wise, David

2010-01-01

The private pension structure in the United States, once dominated by defined benefit (DB) plans, is currently divided between defined contribution (DC) and DB plans. Wealth accumulation in DC plans depends on the participant's contribution behavior and on financial market returns, while accumulation in DB plans is sensitive to a participant's labor market experience and to plan parameters. This paper simulates the distribution of retirement wealth under representative DB and DC plans. It uses data from the Health and Retirement Study (HRS) to explore how asset returns, earnings histories, and retirement plan characteristics contribute to the variation in retirement wealth outcomes. We simulate DC plan accumulation by randomly assigning individuals a share of wages that they and their employer contribute to the plan. We consider several possible asset allocation strategies, with asset returns drawn from the historical return distribution. Our DB plan simulations draw earnings histories from the HRS, and randomly assign each individual a pension plan drawn from a sample of large private and public defined benefit plans. The simulations yield distributions of both DC and DB wealth at retirement. Average retirement wealth accruals under current DC plans exceed average accruals under private sector DB plans, although DC plans are also more likely to generate very low retirement wealth outcomes. The comparison of current DC plans with more generous public sector DB plans is less definitive, because public sector DB plans are more generous on average than their private sector counterparts. PMID:21057597

Electron-beam irradiation-induced gate oxide degradation

NASA Astrophysics Data System (ADS)

Cho, Byung Jin; Chong, Pei Fen; Chor, Eng Fong; Joo, Moon Sig; Yeo, In Seok

2000-12-01

Gate oxide degradation induced by electron-beam irradiation has been studied. A large increase in the low-field excess leakage current was observed on irradiated oxides and this was very similar to electrical stress-induced leakage currents. Unlike conventional electrical stress-induced leakage currents, however, electron-beam induced leakage currents exhibit a power law relationship with fluency without any signs of saturation. It has also been found that the electron-beam neither accelerates nor initiates quasibreakdown of the ultrathin gate oxide. Therefore, the traps generated by electron-beam irradiation do not contribute to quasibreakdown, only to the leakage current.

The reasons for betel-quid chewing scale: assessment of factor structure, reliability, and validity

PubMed Central

2014-01-01

Background Despite the fact that betel-quid is one of the most commonly used psychoactive substances worldwide and a major risk-factor for head-and-neck cancer incidence and mortality globally, currently no standardized instrument is available to assess the reasons why individuals chew betel-quid. A measure to assess reasons for chewing betel-quid could help researchers and clinicians develop prevention and treatment strategies. In the current study, we sought to develop and evaluate a self-report instrument for assessing the reasons for chewing betel quid which contributes toward the goal of developing effective interventions to reduce betel quid chewing in vulnerable populations. Methods The current study assessed the factor structure, reliability and convergent validity of the Reasons for Betel-quid Chewing Scale (RBCS), a newly developed 10 item measure adapted from several existing “reasons for smoking” scales. The measure was administered to 351 adult betel-quid chewers in Guam. Results Confirmatory factor analysis of this measure revealed a three factor structure: reinforcement, social/cultural, and stimulation. Further tests revealed strong support for the internal consistency and convergent validity of this three factor measure. Conclusion The goal of designing an intervention to reduce betel-quid chewing necessitates an understanding of why chewers chew; the current study makes considerable contributions towards that objective. PMID:24889863

The reasons for betel-quid chewing scale: assessment of factor structure, reliability, and validity.

PubMed

Little, Melissa A; Pokhrel, Pallav; Murphy, Kelle L; Kawamoto, Crissy T; Suguitan, Gil S; Herzog, Thaddeus A

2014-06-03

Despite the fact that betel-quid is one of the most commonly used psychoactive substances worldwide and a major risk-factor for head-and-neck cancer incidence and mortality globally, currently no standardized instrument is available to assess the reasons why individuals chew betel-quid. A measure to assess reasons for chewing betel-quid could help researchers and clinicians develop prevention and treatment strategies. In the current study, we sought to develop and evaluate a self-report instrument for assessing the reasons for chewing betel quid which contributes toward the goal of developing effective interventions to reduce betel quid chewing in vulnerable populations. The current study assessed the factor structure, reliability and convergent validity of the Reasons for Betel-quid Chewing Scale (RBCS), a newly developed 10 item measure adapted from several existing "reasons for smoking" scales. The measure was administered to 351 adult betel-quid chewers in Guam. Confirmatory factor analysis of this measure revealed a three factor structure: reinforcement, social/cultural, and stimulation. Further tests revealed strong support for the internal consistency and convergent validity of this three factor measure. The goal of designing an intervention to reduce betel-quid chewing necessitates an understanding of why chewers chew; the current study makes considerable contributions towards that objective.

5 CFR 1620.42 - Processing TSP contribution elections.

Code of Federal Regulations, 2010 CFR

2010-01-01

... she must make a new contribution election to begin current contributions. (b) Makeup contribution... within 60 days of the participant's reemployment or return to pay status. (c) Makeup contributions. Makeup contributions will be processed as follows: (1) If the employee had a valid contribution election...

Emission of atmospherically significant halocarbons by naturally occurring and farmed tropical macroalgae

NASA Astrophysics Data System (ADS)

Leedham, E. C.; Hughes, C.; Keng, F. S. L.; Phang, S.-M.; Malin, G.; Sturges, W. T.

2013-01-01

Current estimates of global halocarbon emissions highlight the tropical coastal environment as an important source of very short-lived (VSL) biogenic halocarbons to the troposphere and stratosphere. This is due to a combination of assumed high primary productivity in tropical coastal waters and the prevalence of deep convective transport potentially capable of rapidly lifting surface emissions to the upper troposphere/lower stratosphere. However, despite this perceived importance direct measurements of tropical coastal biogenic halocarbon emissions, notably from macroalgae (seaweeds), have not been made. In light of this, we provide the first dedicated study of halocarbon production by a range of 15 common tropical macroalgal species and compare these results to those from previous studies of polar and temperate macroalgae. Variation between species was substantial; CHBr3 measured at the end of a 24 h incubation varied from 1.4 to 1129 pmol g FW-1 h-1 (FW = fresh weight of sample). We used our laboratory-determined emission rates to estimate emissions of CHBr3 and CH2Br2 (the two dominant VSL precursors of stratospheric bromine) from the coastlines of Malaysia and South East Asia. We compare these values to previous top-down model estimates of emissions from these regions, and conclude that the contribution of coastal CHBr3 emissions is likely to be lower than previously assumed. The contribution of tropical aquaculture to current emission budgets is also considered. Whilst the current aquaculture contribution to halocarbon emissions in this regional is small, the potential exists for substantial increases in aquaculture to make a significant contribution to regional halocarbon budgets.

Dynamic Harris current sheet thickness from Cluster current density and plasma measurements

NASA Technical Reports Server (NTRS)

Thompson, S. M.; Kivelson, M. G.; Khurana, K. K.; McPherron, R. L.; Weygand, J. M.; Balogh, A.; Reme, H.; Kistler, L. M.

2005-01-01

We use the first accurate measurements of current densities in the plasma sheet to calculate the half-thickness and position of the current sheet as a function of time. Our technique assumes a Harris current sheet model, which is parameterized by lobe magnetic field B(o), current sheet half-thickness h, and current sheet position z(sub o). Cluster measurements of magnetic field, current density, and plasma pressure are used to infer the three parameters as a function of time. We find that most long timescale (6-12 hours) current sheet crossings observed by Cluster cannot be described by a static Harris current sheet with a single set of parameters B(sub o), h, and z(sub o). Noting the presence of high-frequency fluctuations that appear to be superimposed on lower frequency variations, we average over running 6-min intervals and use the smoothed data to infer the parameters h(t) and z(sub o)(t), constrained by the pressure balance lobe magnetic field B(sub o)(t). Whereas this approach has been used in previous studies, the spatial gnuhen& now provided by the Cluster magnetometers were unavailable or not well constrained in earlier studies. We place the calculated hdf&cknessa in a magnetospheric context by examining the change in thickness with substorm phase for three case study events and 21 events in a superposed epoch analysis. We find that the inferred half-thickness in many cases reflects the nominal changes experienced by the plasma sheet during substorms (i.e., thinning during growth phase, thickening following substorm onset). We conclude with an analysis of the relative contribution of (Delta)B(sub z)/(Delta)X to the cross-tail current density during substorms. We find that (Delta)B(sub z)/(Delta)X can contribute a significant portion of the cross-tail c m n t around substorm onset.

Perceptions of barriers to paternal presence and contribution during childbirth: an exploratory study from Syria.

PubMed

Abushaikha, Lubna; Massah, Rana

2013-03-01

The barriers that face fathers during childbirth are an understudied phenomenon. The objective of our study was to explore Syrian parents' perceptions of barriers to paternal presence and contribution during childbirth. A descriptive phenomenological qualitative approach based on Colaizzi's method was used with a purposive sample of 23 mothers and 14 fathers recruited from a major public maternity hospital in Syria. In our study, four themes on barriers to paternal presence and contribution during childbirth were found: 1) sociocultural influences and rigidity; 2) being unprepared; 3) unsupportive policies and attitudes; and 4) unfavorable reactions and circumstances. Common and current sociocultural norms in Syria do not encourage fathers to be present or contribute during childbirth. Therefore, establishing culturally sensitive supportive policies and practices is a vital step toward overcoming these barriers. © 2013, Copyright the Authors Journal compilation © 2013, Wiley Periodicals, Inc.

A simple molecular orbital treatment of current distributions in quantum transport through molecular junctions

NASA Astrophysics Data System (ADS)

Jhan, Sin-Mu; Jin, Bih-Yaw

2017-11-01

A simple molecular orbital treatment of local current distributions inside single molecular junctions is developed in this paper. Using the first-order perturbation theory and nonequilibrium Green's function techniques in the framework of Hückel theory, we show that the leading contributions to local current distributions are directly proportional to the off-diagonal elements of transition density matrices. Under the orbital approximation, the major contributions to local currents come from a few dominant molecular orbital pairs which are mixed by the interactions between the molecule and electrodes. A few simple molecular junctions consisting of single- and multi-ring conjugated systems are used to demonstrate that local current distributions inside molecular junctions can be decomposed by partial sums of a few leading contributing transition density matrices.

Pancharatnam-Berry phase and kinetic magnetoelectric effect in trigonal tellurium

NASA Astrophysics Data System (ADS)

Şahin, C.; Rou, J.; Ma, J.; Pesin, D. A.

2018-05-01

We study the kinetic magnetoelectric effect (current-induced magnetization including both the orbital and spin contributions) in three-dimensional conductors, specializing to the case of p -doped trigonal tellurium. We include both intrinsic and extrinsic contributions to the effect, which stem from the band structure of the crystal, and from disorder scattering, respectively. Specifically, we determine the dependence of the kinetic magnetoelectric response on the hole doping in tellurium, and show that the intrinsic and extrinsic effects dominate for low and high levels of doping, respectively. The results of this work imply that three-dimensional helical metals are promising for spintronics applications, in particular, they can provide robust control over current-induced magnetic torques.

Misinformation contributing to safety issues in vehicle restraints for children : a rural/urban comparison.

DOT National Transportation Integrated Search

2013-12-01

This study sought to determine current knowledge-levels of health care providers regarding child passenger safety issues and frequency of counseling on this topic. In addition, this study explored the differences in child restraint knowledge levels a...

Electroweak penguins at LHCb

NASA Astrophysics Data System (ADS)

He, Jibo; LHCb Collaboration

2016-04-01

Electroweak penguin decays are flavour-changing neutral current processes, and are highly suppressed in the Standard Model. They can only proceed via loop diagrams. Such decays may receive contributions from New Physics and change their decay behaviours like decay rate and angular distribution. Studying the properties of these decays thus provides a powerful method to probe for New Physics. In this contribution the most recent LHCb results on electroweak penguin decays are reported.

Strong Overtones Modes in Inelastic Electron Tunneling Spectroscopy with Cross-Conjugated Molecules: A Prediction from Theory

PubMed Central

2013-01-01

Cross-conjugated molecules are known to exhibit destructive quantum interference, a property that has recently received considerable attention in single-molecule electronics. Destructive quantum interference can be understood as an antiresonance in the elastic transmission near the Fermi energy and leading to suppressed levels of elastic current. In most theoretical studies, only the elastic contributions to the current are taken into account. In this paper, we study the inelastic contributions to the current in cross-conjugated molecules and find that while the inelastic contribution to the current is larger than for molecules without interference, the overall behavior of the molecule is still dominated by the quantum interference feature. Second, an ongoing challenge for single molecule electronics is understanding and controlling the local geometry at the molecule-surface interface. With this in mind, we investigate a spectroscopic method capable of providing insight into these junctions for cross-conjugated molecules: inelastic electron tunneling spectroscopy (IETS). IETS has the advantage that the molecule interface is probed directly by the tunneling current. Previously, it has been thought that overtones are not observable in IETS. Here, overtones are predicted to be strong and, in some cases, the dominant spectroscopic features. We study the origin of the overtones and find that the interference features in these molecules are the key ingredient. The interference feature is a property of the transmission channels of the π system only, and consequently, in the vicinity of the interference feature, the transmission channels of the σ system and the π system become equally transmissive. This allows for scattering between the different transmission channels, which serves as a pathway to bypass the interference feature. A simple model calculation is able to reproduce the results obtained from atomistic calculations, and we use this to interpret these findings. PMID:24067128

Dimensions of service quality in healthcare: a systematic review of literature.

PubMed

Fatima, Iram; Humayun, Ayesha; Iqbal, Usman; Shafiq, Muhammad

2018-06-13

Various dimensions of healthcare service quality were used and discussed in literature across the globe. This study presents an updated meaningful review of the extensive research that has been conducted on measuring dimensions of healthcare service quality. Systematic review method in current study is based on PRISMA guidelines. We searched for literature using databases such as Google, Google Scholar, PubMed and Social Science, Citation Index. In this study, we screened 1921 identified papers using search terms/phrases. Snowball strategies were adopted to extract published articles from January 1997 till December 2016. Two-hundred and fourteen papers were identified as relevant for data extraction; completed by two researchers, double checked by the other two to develop agreement in discrepancies. In total, 74 studies fulfilled our pre-defined inclusion and exclusion criteria for data analysis. Service quality is mainly measured as technical and functional, incorporating many sub-dimensions. We synthesized the information about dimensions of healthcare service quality with reference to developed and developing countries. 'Tangibility' is found to be the most common contributing factor whereas 'SERVQUAL' as the most commonly used model to measure healthcare service quality. There are core dimensions of healthcare service quality that are commonly found in all models used in current reviewed studies. We found a little difference in these core dimensions while focusing dimensions in both developed and developing countries, as mostly SERVQUAL is being used as the basic model to either generate a new one or to add further contextual dimensions. The current study ranked the contributing factors based on their frequency in literature. Based on these priorities, if factors are addressed irrespective of any context, may lead to contribute to improve healthcare quality and may provide an important information for evidence-informed decision-making.

"JTPE": A 30-Year Retrospective of Published Research

ERIC Educational Resources Information Center

Rhoades, Jesse L.; Woods, Amelia M.; Daum, David N.; Ellison, Douglas; Trendowski, Thomas N.

2016-01-01

This case study presents an examination of 30 years of "Journal of Teaching in Physical Education" ("JTPE") research. The purpose of this study was to provide a retrospective view of "JTPE" and its contribution to the field of physical education. In this effort the current study employed citation analysis, co-author…

The Voices of School Counselors: Essential Characteristics of School Counselor Leaders

ERIC Educational Resources Information Center

Young, Anita; Dollarhide, Colette T.; Baughman, Amber

2015-01-01

The majority of school counselor leadership studies focus on quantitative data. The current study contributes to the limited qualitative research surrounding school counselor leadership. The analysis of an open-ended statement from a national study gives voice to school counselor perceptions about leadership characteristics pertinent to the…

Gender career divide and women's disadvantage in depressive symptoms and physical limitations in France.

PubMed

Cambois, Emmanuelle; Garrouste, Clémentine; Pailhé, Ariane

2017-12-01

This study investigated the relationship between women's disadvantage in mental health and physical functioning and gender differences in career backgrounds. Sexual division of labor persists and key career characteristics are overrepresented in women: low-skilled first job, downward occupational trajectory, interruptions. These interrelated characteristics are usually linked to poor health. Their overrepresentation in women may be related to the female-male health gap; however, it may not if overrepresentation transposed into substantially weaker associations with poor health outcomes. To address this question, we used the French population survey "Health and Occupational Trajectories" (2006) and focused on 45-74 year-old individuals who ever worked (n=7537). Past career characteristics were qualified by retrospective information. Logistic regressions identified past characteristics related to current depressive symptoms and physical limitations. Non-linear decomposition showed whether these characteristics contributed to the gender health gap, through their different distribution and/or association with health. The overrepresentation of unskilled first jobs, current and past inactivity and unemployment in women contributed to their excess depressive symptoms. These contributions were only slightly reduced by the weaker mental health-relatedness of current inactivity in women and increased by the stronger relatedness of low-skilled and self-employed first jobs. Overrepresentation of current inactivity, past interruptions and downward trajectories also contributed positively to women's excess physical limitations. Gender-specific career backgrounds were significantly linked to women's disadvantage in mental health and physical functioning. We need to further explore whether equalization of opportunities, especially at the early stages and in terms of career continuity, could help to reduce women's mental and physical health disadvantage.

Authorship and contribution disclosures

PubMed Central

Sauermann, Henry; Haeussler, Carolin

2017-01-01

Most scientific research is performed by teams, and for a long time, observers have inferred individual team members’ contributions by interpreting author order on published articles. In response to increasing concerns about this approach, journals are adopting policies that require the disclosure of individual authors’ contributions. However, it is not clear whether and how these disclosures improve upon the conventional approach. Moreover, there is little evidence on how contribution statements are written and how they are used by readers. We begin to address these questions in two studies. Guided by a conceptual model, Study 1 examines the relationship between author order and contribution statements on more than 12,000 articles to understand what information is provided by each. This analysis quantifies the risk of error when inferring contributions from author order and shows how this risk increases with team size and for certain types of authors. At the same time, the analysis suggests that some components of the value of contributions are reflected in author order but not in currently used contribution statements. Complementing the bibliometric analysis, Study 2 analyzes survey data from more than 6000 corresponding authors to examine how contribution statements are written and used. This analysis highlights important differences between fields and between senior versus junior scientists, as well as strongly diverging views about the benefits and limitations of contribution statements. On the basis of both studies, we highlight important avenues for future research and consider implications for a broad range of stakeholders. PMID:29152564

Digitisation of Local Heritage: Local Studies Collections and Digitisation in Public Libraries

ERIC Educational Resources Information Center

Smith, Lucy; Rowley, Jennifer

2012-01-01

This study explores the application of digitisation in the context of public library local studies services. Since there has been limited previous research on digitisation and local studies collections, this research makes an important contribution in profiling the current situation, and highlighting the extent to which progress is limited in the…

Childhood emotional maltreatment as a robust predictor of suicidal ideation: A multi-wave, prospective investigation

PubMed Central

Miller, Adam Bryant; Jenness, Jessica L.; Oppenheimer, Caroline W.; Barrocas Gottleib, Andrea L.; Young, Jami F.; Hankin, Benjamin L.

2016-01-01

Despite literature suggesting a relationship between child maltreatment and suicidal ideation, few studies have examined the prospective course of this relationship. The current study examined this relationship in a sample of 682 community youth who were followed over the course of 3 years. Repeated measures of suicidal ideation, emotional maltreatment, and depressive symptom severity were examined in multi-wave path analysis models. Overall, results suggest that emotional maltreatment over time contributes uniquely to the prospective prediction of suicidal ideation, even when controlling for age, previous suicidal ideation, biological sex, and depression symptom severity. Unlike previous studies that have only measured emotional maltreatment at one-time point, the current study demonstrates that emotional maltreatment contributes unique risk to suicidal ideation prospectively among youth. Results speak to the importance of examining emotional maltreatment and suicidal ideation within prospective models of risk and suggest that emotional maltreatment is a robust predictor of suicidal ideation, over and above history of suicidal ideation and depression. PMID:27032784

Exploration and comparison of inborn capacity of aerobic and anaerobic metabolisms of Saccharomyces cerevisiae for microbial electrical current production.

PubMed

Mao, Longfei; Verwoerd, Wynand S

2013-01-01

Saccharomyces cerevisiae possesses numerous advantageous biological features, such as being robust, easily handled, mostly non-pathogenic and having high catabolic rates, etc., which can be considered as merits for being used as a promising biocatalyst in microbial fuel cells (MFCs) for electricity generation. Previous studies have developed efficient MFC configurations to convert metabolic electron shuttles, such as cytoplasmic NADH, into usable electric current. However, no studies have elucidated the maximum potential of S. cerevisiae for current output and the underlying metabolic pathways, resulting from the interaction of thousands of reactions inside the cell during MFC operation. To address these two key issues, this study used in silico metabolic engineering techniques, flux balance analysis (FBA), and flux variability analysis with target flux minimization (FATMIN), to model the metabolic perturbation of S. cerevisiae under the MFC-energy extraction. The FBA results showed that, in the cytoplasmic NADH-dependent mediated electron transfer (MET) mode, S. cerevisiae had a potential to produce currents at up to 5.781 A/gDW for the anaerobic and 6.193 A/gDW for the aerobic environments. The FATMIN results showed that the aerobic and anaerobic metabolisms are resilient, relying on six and five contributing reactions respectively for high current production. Two reactions, catalyzed by glutamate dehydrogenase (NAD) (EC 1.4.1.3) and methylene tetrahydrofolate dehydrogenase (NAD) (EC 1.5.1.5), were shared in both current-production modes and contributed to over 80% of the identified maximum current outputs. It is also shown that the NADH regeneration was much less energy costly than biomass production rate. Taken together, our finding suggests that S. cerevisiae should receive more research effort for MFC electricity production.

Exploration and comparison of inborn capacity of aerobic and anaerobic metabolisms of Saccharomyces cerevisiae for microbial electrical current production

PubMed Central

Mao, Longfei; Verwoerd, Wynand S

2013-01-01

Saccharomyces cerevisiae possesses numerous advantageous biological features, such as being robust, easily handled, mostly non-pathogenic and having high catabolic rates, etc., which can be considered as merits for being used as a promising biocatalyst in microbial fuel cells (MFCs) for electricity generation. Previous studies have developed efficient MFC configurations to convert metabolic electron shuttles, such as cytoplasmic NADH, into usable electric current. However, no studies have elucidated the maximum potential of S. cerevisiae for current output and the underlying metabolic pathways, resulting from the interaction of thousands of reactions inside the cell during MFC operation. To address these two key issues, this study used in silico metabolic engineering techniques, flux balance analysis (FBA), and flux variability analysis with target flux minimization (FATMIN), to model the metabolic perturbation of S. cerevisiae under the MFC-energy extraction. The FBA results showed that, in the cytoplasmic NADH-dependent mediated electron transfer (MET) mode, S. cerevisiae had a potential to produce currents at up to 5.781 A/gDW for the anaerobic and 6.193 A/gDW for the aerobic environments. The FATMIN results showed that the aerobic and anaerobic metabolisms are resilient, relying on six and five contributing reactions respectively for high current production. Two reactions, catalyzed by glutamate dehydrogenase (NAD) (EC 1.4.1.3) and methylene tetrahydrofolate dehydrogenase (NAD) (EC 1.5.1.5), were shared in both current-production modes and contributed to over 80% of the identified maximum current outputs. It is also shown that the NADH regeneration was much less energy costly than biomass production rate. Taken together, our finding suggests that S. cerevisiae should receive more research effort for MFC electricity production. PMID:23969939

Monitoring and remediation of on-farm and off-farm ground current measured as step potential on a Wisconsin dairy farm: A case study.

PubMed

Stetzer, Dave; Leavitt, Adam M; Goeke, Charles L; Havas, Magda

2016-01-01

Ground current commonly referred to as "stray voltage" has been an issue on dairy farms since electricity was first brought to rural America. Equipment that generates high-frequency voltage transients on electrical wires combined with a multigrounded (electrical distribution) system and inadequate neutral returns all contribute to ground current. Despite decades of problems, we are no closer to resolving this issue, in part, due to three misconceptions that are addressed in this study. Misconception 1. The current standard of 1 V at cow contact is adequate to protect dairy cows; Misconception 2. Frequencies higher than 60 Hz do not need to be considered; and Misconception 3. All sources of ground current originate on the farm that has a ground current problem. This case study of a Wisconsin dairy farm documents, 1. how to establish permanent monitoring of ground current (step potential) on a dairy farm; 2. how to determine and remediate both on-farm and off-farm sources contributing to step potential; 3. which step-potential metrics relate to cow comfort and milk production; and 4. how these metrics relate to established standards. On-farm sources include lighting, variable speed frequency drives on motors, radio frequency identification system and off-farm sources are due to a poor primary neutral return on the utility side of the distribution system. A step-potential threshold of 1 V root mean square (RMS) at 60 Hz is inadequate to protect dairy cows as decreases of a few mV peak-peak at higher frequencies increases milk production, reduces milking time and improves cow comfort.

Progress On Neutrino-Proton Neutral-Current Scattering In MicroBooNE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pate, Stephen

2017-01-16

The MicroBooNE Experiment at the Fermi National Accelerator Laboratory, an 89-ton active mass liquid argon time projection chamber, affords a unique opportunity to observe low-more » $Q^2$ neutral-current neutrino-proton scattering events. Neutral-current neutrino-proton scattering at $Q^2 < 1$ GeV$^2$ is dominated by the proton's axial form factor, which can be written as a combination of contributions from the up, down, and strange quarks: $$G_A(Q^2) = \\frac{1}{2}[-G_A^u(Q^2)+G_A^d(Q^2)+G_A^s(Q^2)]$$. The contribution from up and down quarks has been established in past charged-current measurements. The contribution from strange quarks at low $Q^2$ remains unmeasured; this is of great interest since the strange quark contribution to the proton spin can be determined from the low-$Q^2$ behavior: $$\\Delta S = G_A^s(Q^2=0)$$. MicroBooNE began operating in the Booster Neutrino Beam in October 2015. I will present the status in observing isolated proton tracks in the MicroBooNE detector as a signature for neutral-current neutrino-proton events. The sensitivity of the MicroBooNE experiment for measuring the strange quark contribution to the proton spin will be discussed.« less

Teaching the Banking System According to Critical Education. A Study of a Schoolbook on Economics

ERIC Educational Resources Information Center

Vaina, Maria; Katidioti, Evaggelia; Ktitikos, Antonis

2013-01-01

The main objective of the current paper is to establish the deficiencies of teaching Economics in the Greek educational system. It also proposes critical education as a way of partially overcoming these issues and the way it can contribute to the protection of the everyday man and woman against the rising and current existential threats of the…

Photo-electronic current transport in back-gated graphene transistor

NASA Astrophysics Data System (ADS)

Srivastava, Ashok; Chen, Xinlu; Pradhan, Aswini K.

2017-04-01

In this work, we have studied photo-electronic current transport in a back-gated graphene field-effect transistor. Under the light illumination, band bending at the metal/graphene interface develops a built-in potential which generates photonic current at varying back-gate biases. A typical MOSFET type back-gated transistor structure uses a monolayer graphene as the channel layer formed over the silicon dioxide/silicon substrate. It is shown that the photo-electronic current consists of current contributions from photovoltaic, photo-thermoelectric and photo-bolometric effects. A maximum external responsivity close to 0.0009A/W is achieved at 30μW laser power source and 633nm wavelength.

Encouraging Active School Travel by Making it "Cool": A Quasi-Experimental Study Using Boltage, Phase II

DOT National Transportation Integrated Search

2015-05-01

The research on childrens school travel has studied the impacts of the built environment on children walking or biking to school. This three-year research project contributes to current literature by investigating the role played by socio-psycholo...

Black Contributions to the Early History of Western Medicine: Lack of Recognition as a Cause of Black Under-Representation in US Medical Schools

PubMed Central

Newsome, Frederick

1979-01-01

During several millenia, blacks in ancient Egypt made numerous contributions to medicine and were acknowledged as the inventors of the art of medicine. They produced the earliest physicians, medical knowledge, and medical literature. They contributed to the development of medicine in ancient Greece. Ancient writers, including Herodotus, Isocrates, and Diodorus, affirm this. Modern presentations of ancient medicine, however, deprive blacks of the knowledge of their early contributions to medicine by ignoring or subtly misrepresenting the black identity of the ancient Egyptians. Blacks are currently under-represented in US medical schools. It is proposed that the recognition of the contributions of blacks to the early history of Western medicine would inspire black students to study medicine. PMID:423296

The Contribution of Sleep Problems to Academic and Psychosocial Functioning

ERIC Educational Resources Information Center

Perfect, Michelle M.; Levine-Donnerstein, Deborah; Archbold, Kristen; Goodwin, James L.; Quan, Stuart F.

2014-01-01

The current study examined the concurrent and longitudinal relations among sleep problems with academic and psychosocial functioning in a prospective cohort study, the Tucson Children's Assessment of Sleep Apnea study (TuCASA). Children were assessed between the ages of 6 and 11 years and again approximately 5 years later. Sleep disordered…

Women in Mathematics: A Nested Approach

ERIC Educational Resources Information Center

Köse, Emek; Johnson, Angela C.

2016-01-01

In this article, we present a case study of a course called Women in Mathematics. Students in the course studied the lives and the mathematical contributions of women mathematicians throughout history, as well as current gender equity issues in the study of mathematics and in mathematical careers. They also mentored 20 middle school girls…

Interteaching: The Effects of Quality Points on Exam Scores

ERIC Educational Resources Information Center

Saville, Bryan K.; Zinn, Tracy E.

2009-01-01

Although previous studies have found interteaching to be an effective alternative to traditional methods of instruction, few studies have examined which of its components contribute to its effectiveness. In the current study, we examined whether manipulating quality points had an effect on our students' exam scores. In two sections of an…

Dietary ω-3 polyunsaturated fatty acids improves learning performance of diabetic rats by regulating the neuron excitability.

PubMed

Yang, R-H; Wang, F; Hou, X-H; Cao, Z-P; Wang, B; Xu, X-N; Hu, S-J

2012-06-14

Previous research has demonstrated that diabetes induced learning and memory deficits. However, the mechanism of memory impairment induced by diabetes is poorly understood. Dietary fatty acids, especially polyunsaturated fatty acids (PUFA), have been shown to enhance learning and memory and prevent memory deficits in various experimental conditions. Sprague-Dawley rats were used in the present study to investigate the effect of fish oil supplementation on spatial learning and memory of streptozotocin (STZ)-induced diabetic rats with the Morris Water Maze. The excitability of CA1 pyramidal neurons and the related ionic currents was also examined. Diabetes impaired spatial learning and memory of rats. Diabetes decreased the sodium currents and increased the potassium currents, and further led to the reduction of excitability of CA1 pyramidal neurons, effects which may contribute to the behavioral deficits. Fish oil dietary supplementation decreased the transient currents and Kv4.2 expression in the hippocampus and partially improved learning performance of diabetic rats. The results of the present study suggested that sodium and potassium currents contributed to the inhibitory effect of diabetes on neuron excitability, further influencing learning and memory processing. Dietary fish oil may modulate the membrane excitability and is a possible strategy for preventing the impairments of diabetes on hippocampal function. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Contribution of ASDEX Upgrade to disruption studies for ITER

NASA Astrophysics Data System (ADS)

Pautasso, G.; Zhang, Y.; Reiter, B.; Giannone, L.; Gruber, O.; Herrmann, A.; Kardaun, O.; Khayrutdinov, K. K.; Lukash, V. E.; Maraschek, M.; Mlynek, A.; Nakamura, Y.; Schneider, W.; Sias, G.; Sugihara, M.; ASDEX Upgrade Team

2011-10-01

This paper describes the most recent contributions of ASDEX Upgrade to ITER in the field of disruption studies. (1) The ITER specifications for the halo current magnitude are based on data collected from several tokamaks and summarized in the plot of the toroidal peaking factor versus the maximum halo current fraction. Even if the maximum halo current in ASDEX Upgrade reaches 50% of the plasma current, the duration of this maximum lasts a fraction of a ms. (2) Long-lasting asymmetries of the halo current are rare and do not give rise to a large asymmetric component of the mechanical forces on the machine. Differently from JET, these asymmetries are neither locked nor exhibit a stationary harmonic structure. (3) Recent work on disruption prediction has concentrated on the search for a simple function of the most relevant plasma parameters, which is able to discriminate between the safe and pre-disruption phases of a discharge. For this purpose, the disruptions of the last four years have been classified into groups and then discriminant analysis is used to select the most significant variables and to derive the discriminant function. (4) The attainment of the critical density for the collisional suppression of the runaway electrons seems to be technically and physically possible on our medium size tokamak. The CO2 interferometer and the AXUV diagnostic provide information on the highly 3D impurity transport process during the whole plasma quench.

Secondary Amenorrhea among Female Athletes. Current Understandings.

ERIC Educational Resources Information Center

Sasiene, Gwen Hagenbuch

1983-01-01

Research pertaining to female athletes' problems with secondary amenorrhea is reviewed. Studies point to stress, weight loss, anorexia nervosa, obesity, arduous athletic training, and age of onset of training as factors which may contribute to this disorder. (PP)

Issues in Locomotive Crew Management and Scheduling

DOT National Transportation Integrated Search

1990-11-01

This study explores matters related to the scheduling and management of locomotive crews, particularly as they : might contribute to fatigue and stress. It describes how crews are scheduled currently, why there is so much : unpredictability in schedu...

Study of the physical discharge properties of a Ar/O2 DC plasma jet

NASA Astrophysics Data System (ADS)

Barkhordari, A.; Ganjovi, A.; Mirzaei, I.; Falahat, A.

2018-03-01

In this paper, the physical properties of plasma discharge in a manufactured DC plasma jet operating with the Ar/O2 gaseous mixture are studied. Moreover, the optical emission spectroscopy technique is used to perform the experimental measurements. The obtained emission spectra are analyzed and, the plasma density, rotational, vibrational and electronic temperature are calculated. The NO emission lines from {NO }γ( A2 Σ^{+} \\to {X}2 Πr ) electronic transition are observed. It is seen that, at the higher argon contributions in Ar/O2 gaseous mixture, the emission intensities from argon ions will increase. Moreover, while the vibrational and excitation temperatures are increased at the higher input DC currents, they will decrease at the higher Ar percentages in the Ar/O2 gaseous mixture. Furthermore, at the higher DC currents and Ar contributions, both the plasma electron density and dissociation fraction of oxygen atoms are increased.

Contributions of depression and body mass index to body image.

PubMed

Paans, Nadine P G; Bot, Mariska; Brouwer, Ingeborg A; Visser, Marjolein; Penninx, Brenda W J H

2018-05-07

Depression and body mass index (BMI) are known to be associated with body image, however, their independent or joint effects on body image in adults are largely unknown. Therefore, we studied associations of depression diagnosis, severity, and BMI with perceptual body size (PBS) and body image dissatisfaction (BID). Cross-sectional data from 882 remitted depressed patients, 242 currently depressed patients and 325 healthy controls from the Netherlands Study of Depression and Anxiety were used. Depressive disorders (DSM-IV based psychiatric interview), standardized self-reported depressive symptoms (Inventory of Depressive Symptomatology) and BMI were separately and simultaneously related to body image (the Stunkard Figure Rating scale) using linear regression analyses. Thereafter, interaction between depression and BMI was investigated. Analyses were adjusted for demographic and health variables. Higher BMI was associated with larger PBS (B = 1.13, p < .001) and with more BID (B = 0.61, p < .001). Independent of this, depression severity contributed to larger PBS (B = 0.07, p < .001), and both current (B = 0.21, p = .001) and remitted depression diagnosis (B = 0.12, p = .01) as well as depression severity (B = 0.11, p < .001) contributed to BID. There was no interaction effect between BMI and depression in predicting PBS and BID. In general, depression (current, remitted and severity) and higher BMI contribute independently to a larger body size perception as well as higher body image dissatisfaction. Efforts in treatment should be made to reduce body dissatisfaction in those suffering from depression and/or a high BMI, as BID can have long-lasting health consequences, such as development of anorexia and bulimia nervosa and an unhealthy lifestyle. Copyright © 2018 Elsevier Ltd. All rights reserved.

Are health inequalities rooted in the past? Income inequalities in metabolic syndrome decomposed by childhood conditions

PubMed Central

San Sebastian, Miguel; Ivarsson, Anneli; Weinehall, Lars; Gustafsson, Per E.

2017-01-01

Abstract Background: Early life is thought of as a foundation for health inequalities in adulthood. However, research directly examining the contribution of childhood circumstances to the integrated phenomenon of adult social inequalities in health is absent. The present study aimed to examine whether, and to what degree, social conditions during childhood explain income inequalities in metabolic syndrome in mid-adulthood. Methods: The sample (N = 12 481) comprised all 40- and 50-year-old participants in the Västerbotten Intervention Program in Northern Sweden 2008, 2009 and 2010. Measures from health examinations were used to operationalize metabolic syndrome, which was linked to register data including socioeconomic conditions at age 40–50 years, as well as childhood conditions at participant age 10–12 years. Income inequality in metabolic syndrome in middle age was estimated by the concentration index and decomposed by childhood and current socioeconomic conditions using decomposition analysis. Results: Childhood conditions jointed explained 7% (men) to 10% (women) of health inequalities in middle age. Adding mid-adulthood sociodemographic factors showed a dominant contribution of chiefly current income and educational level in both gender. In women, the addition of current factors slightly attenuated the contribution of childhood conditions, but with paternal income and education still contributing. In contrast, the corresponding addition in men removed all explanation attributable to childhood conditions. Conclusions: Despite that the influence of early life conditions to adult health inequalities was considerably smaller than that of concurrent conditions, the study suggests that early interventions against social inequalities potentially could reduce health inequalities in the adult population for decades to come. PMID:27744345

TRPV2 Channels Contribute to Stretch-Activated Cation Currents and Myogenic Constriction in Retinal Arterioles.

PubMed

McGahon, Mary K; Fernández, José A; Dash, Durga P; McKee, Jon; Simpson, David A; Zholos, Alex V; McGeown, J Graham; Curtis, Tim M

2016-10-01

Activation of the transient receptor potential channels, TRPC6, TRPM4, and TRPP1 (PKD2), has been shown to contribute to the myogenic constriction of cerebral arteries. In the present study we sought to determine the potential role of various mechanosensitive TRP channels to myogenic signaling in arterioles of the rat retina. Rat retinal arterioles were isolated for RT-PCR, Fura-2 Ca2+ microfluorimetry, patch-clamp electrophysiology, and pressure myography studies. In some experiments, confocal immunolabeling of wholemount preparations was used to examine the localization of specific mechanosensitive TRP channels in retinal vascular smooth muscle cells (VSMCs). Reverse transcription-polymerase chain reaction analysis demonstrated mRNA expression for TRPC1, M7, V1, V2, V4, and P1, but not TRPC6 or M4, in isolated retinal arterioles. Immunolabeling revealed plasma membrane, cytosolic and nuclear expression of TRPC1, M7, V1, V2, V4, and P1 in retinal VSMCs. Hypoosmotic stretch-induced Ca2+ influx in retinal VSMCs was reversed by the TRPV2 inhibitor tranilast and the nonselective TRPP1/V2 antagonist amiloride. Inhibitors of TRPC1, M7, V1, and V4 had no effect. Hypoosmotic stretch-activated cation currents were similar in Na+ and Cs+ containing solutions suggesting no contribution by TRPP1 channels. Direct plasma membrane stretch triggered cation current activity that was blocked by tranilast and specific TRPV2 pore-blocking antibodies and mimicked by the TRPV2 activator, Δ9-tetrahydrocannabinol. Preincubation of retinal arterioles with TRPV2 blocking antibodies prevented the development of myogenic tone. Our results suggest that retinal VSMCs express a range of mechanosensitive TRP channels, but only TRPV2 appears to contribute to myogenic signaling in this vascular bed.

An interpretation of induced electric currents in long pipelines caused by natural geomagnetic sources of the upper atmosphere

USGS Publications Warehouse

Campbell, W.H.

1986-01-01

Electric currents in long pipelines can contribute to corrosion effects that limit the pipe's lifetime. One cause of such electric currents is the geomagnetic field variations that have sources in the Earth's upper atmosphere. Knowledge of the general behavior of the sources allows a prediction of the occurrence times, favorable locations for the pipeline effects, and long-term projections of corrosion contributions. The source spectral characteristics, the Earth's conductivity profile, and a corrosion-frequency dependence limit the period range of the natural field changes that affect the pipe. The corrosion contribution by induced currents from geomagnetic sources should be evaluated for pipelines that are located at high and at equatorial latitudes. At midlatitude locations, the times of these natural current maxima should be avoided for the necessary accurate monitoring of the pipe-to-soil potential. ?? 1986 D. Reidel Publishing Company.

Inhibitory effect of aniracetam on N-type calcium current in acutely isolated rat neuronal cells.

PubMed

Koike, H; Saito, H; Matsuki, N

1993-04-01

Effects of aniracetam on whole-cell calcium currents were studied in acutely isolated neuronal cells from postnatal rat ventromedial hypothalamus. There were three types of inward calcium currents, one low-threshold transient current and two high-threshold sustained currents. The nicardipine sensitive L-type current was activated at -20 mV or more depolarized potentials, and the omega-conotoxin sensitive N-type current was recorded at more positive potentials than the L-type. Aniracetam inhibited the N-type current in a dose-dependent manner without affecting the other two types of calcium currents. The effect appeared soon after the addition and lasted for several minutes during washing. Since the N-type current is thought to regulate the release of transmitters, the inhibitory effect may contribute to the nootropic property of aniracetam by modifying the neurotransmission.

Contributions of climate change to the boundary shifts in the farming-pastoral ecotone in northern China since 1970

NASA Astrophysics Data System (ADS)

Shi, W.; Liu, Y.; Shi, X.

2017-12-01

Critical transitions of farming-pastoral ecotone (FPE) boundaries can be affected by climate change and human activities, yet current studies have not adequately analyzed the spatially explicit contributions of climate change to FPE boundary shifts, particularly those in different regions and periods. In this study, we present a series of analyses at the point (gravity center analysis), line (boundary shifts detected using two methods) and area (spatial analysis) levels to quantify climate contributions at the 1 km scale in each ecological functional region during three study periods from the 1970s to the 2000s using climate and land use data. Both gravity center analysis and boundary shift detection reveal similar spatial patterns, with more extensive boundary shifts in the northeastern and southeastern parts of the FPE in northern China, especially during the 1970s-1980s and 1990s-2000s. Climate contributions in the X- and Y-coordinate directions and in the directions of transects along boundaries show that significant differences in climate contributions to FPE boundary shifts exist in different ecological regions during the three periods. Additionally, the results in different directions exhibit good agreement in most of the ecological functional regions during most of the periods. However, the contribution values in the directions of transects along the boundaries (with 1-17%) were always smaller than those in the X-and Y-coordinate directions (4-56%), which suggests that the analysis in the transect directions is more stable and reasonable. Thus, this approach provides an alternative method for detecting the climate contributions to boundary shifts associated with land use changes. Spatial analysis of the relationship between climate change and land use change in the context of FPE boundary shifts in northern China provides further evidence and explanation of the driving forces of climate change. Our findings suggest that an improved understanding of the quantitative contributions of climate change to the formation and transition of the FPE in northern China is essential for addressing current and future adaptation and mitigation measures and regional land use management.

Associating ground magnetometer observations with current or voltage generators

NASA Astrophysics Data System (ADS)

Hartinger, M. D.; Xu, Z.; Clauer, C. R.; Yu, Y.; Weimer, D. R.; Kim, H.; Pilipenko, V.; Welling, D. T.; Behlke, R.; Willer, A. N.

2017-07-01

A circuit analogy for magnetosphere-ionosphere current systems has two extremes for drivers of ionospheric currents: ionospheric electric fields/voltages constant while current/conductivity vary—the "voltage generator"—and current constant while electric field/conductivity vary—the "current generator." Statistical studies of ground magnetometer observations associated with dayside Transient High Latitude Current Systems (THLCS) driven by similar mechanisms find contradictory results using this paradigm: some studies associate THLCS with voltage generators, others with current generators. We argue that most of this contradiction arises from two assumptions used to interpret ground magnetometer observations: (1) measurements made at fixed position relative to the THLCS field-aligned current and (2) negligible auroral precipitation contributions to ionospheric conductivity. We use observations and simulations to illustrate how these two assumptions substantially alter expectations for magnetic perturbations associated with either a current or a voltage generator. Our results demonstrate that before interpreting ground magnetometer observations of THLCS in the context of current/voltage generators, the location of a ground magnetometer station relative to the THLCS field-aligned current and the location of any auroral zone conductivity enhancements need to be taken into account.

Be(com)ing an Excellent Student: A Qualitative Study with Engineering Undergraduates

ERIC Educational Resources Information Center

Monteiro, Sílvia; Almeida, Leandro S.; Vasconcelos, Rosa M.; Cruz, José Fernando A.

2014-01-01

This study explores the factors affecting the development of academic excellence on a group of 33 high-achieving engineering students. Participants were interviewed individually to explore several personal and contextual aspects of their past and current academic pathways. The results obtained reflect three main contributions to the…

Genetic Influences on Adolescent Eating Habits

ERIC Educational Resources Information Center

Beaver, Kevin M.; Flores, Tori; Boutwell, Brian B.; Gibson, Chris L.

2012-01-01

Behavioral genetic research shows that variation in eating habits and food consumption is due to genetic and environmental factors. The current study extends this line of research by examining the genetic contribution to adolescent eating habits. Analysis of sibling pairs drawn from the National Longitudinal Study of Adolescent Health (Add Health)…

Development and Maintenance of Identity in Aging Community Music Participants

ERIC Educational Resources Information Center

Dyer, William Leonard

2016-01-01

This ethnographic study contextualized identity development and maintenance within the field of community music through case studies of four performing groups and interviews with seven current members. The underlying question guiding this research was how does participatory music making contribute to the development and maintenance of identity in…

Optimizing a Workplace Learning Pattern: A Case Study from Aviation

ERIC Educational Resources Information Center

Mavin, Timothy John; Roth, Wolff-Michael

2015-01-01

Purpose: This study aims to contribute to current research on team learning patterns. It specifically addresses some negative perceptions of the job performance learning pattern. Design/methodology/approach: Over a period of three years, qualitative and quantitative data were gathered on pilot learning in the workplace. The instructional modes…

Action potentials and ion conductances in wild-type and CALHM1-knockout type II taste cells

PubMed Central

Saung, Wint Thu; Foskett, J. Kevin

2017-01-01

Taste bud type II cells fire action potentials in response to tastants, triggering nonvesicular ATP release to gustatory neurons via voltage-gated CALHM1-associated ion channels. Whereas CALHM1 regulates mouse cortical neuron excitability, its roles in regulating type II cell excitability are unknown. In this study, we compared membrane conductances and action potentials in single identified TRPM5-GFP-expressing circumvallate papillae type II cells acutely isolated from wild-type (WT) and Calhm1 knockout (KO) mice. The activation kinetics of large voltage-gated outward currents were accelerated in cells from Calhm1 KO mice, and their associated nonselective tail currents, previously shown to be highly correlated with ATP release, were completely absent in Calhm1 KO cells, suggesting that CALHM1 contributes to all of these currents. Calhm1 deletion did not significantly alter resting membrane potential or input resistance, the amplitudes and kinetics of Na+ currents either estimated from action potentials or recorded from steady-state voltage pulses, or action potential threshold, overshoot peak, afterhyperpolarization, and firing frequency. However, Calhm1 deletion reduced the half-widths of action potentials and accelerated the deactivation kinetics of transient outward currents, suggesting that the CALHM1-associated conductance becomes activated during the repolarization phase of action potentials. NEW & NOTEWORTHY CALHM1 is an essential ion channel component of the ATP neurotransmitter release mechanism in type II taste bud cells. Its contribution to type II cell resting membrane properties and excitability is unknown. Nonselective voltage-gated currents, previously associated with ATP release, were absent in cells lacking CALHM1. Calhm1 deletion was without effects on resting membrane properties or voltage-gated Na+ and K+ channels but contributed modestly to the kinetics of action potentials. PMID:28202574

Action potentials and ion conductances in wild-type and CALHM1-knockout type II taste cells.

PubMed

Ma, Zhongming; Saung, Wint Thu; Foskett, J Kevin

2017-05-01

Taste bud type II cells fire action potentials in response to tastants, triggering nonvesicular ATP release to gustatory neurons via voltage-gated CALHM1-associated ion channels. Whereas CALHM1 regulates mouse cortical neuron excitability, its roles in regulating type II cell excitability are unknown. In this study, we compared membrane conductances and action potentials in single identified TRPM5-GFP-expressing circumvallate papillae type II cells acutely isolated from wild-type (WT) and Calhm1 knockout (KO) mice. The activation kinetics of large voltage-gated outward currents were accelerated in cells from Calhm1 KO mice, and their associated nonselective tail currents, previously shown to be highly correlated with ATP release, were completely absent in Calhm1 KO cells, suggesting that CALHM1 contributes to all of these currents. Calhm1 deletion did not significantly alter resting membrane potential or input resistance, the amplitudes and kinetics of Na + currents either estimated from action potentials or recorded from steady-state voltage pulses, or action potential threshold, overshoot peak, afterhyperpolarization, and firing frequency. However, Calhm1 deletion reduced the half-widths of action potentials and accelerated the deactivation kinetics of transient outward currents, suggesting that the CALHM1-associated conductance becomes activated during the repolarization phase of action potentials. NEW & NOTEWORTHY CALHM1 is an essential ion channel component of the ATP neurotransmitter release mechanism in type II taste bud cells. Its contribution to type II cell resting membrane properties and excitability is unknown. Nonselective voltage-gated currents, previously associated with ATP release, were absent in cells lacking CALHM1. Calhm1 deletion was without effects on resting membrane properties or voltage-gated Na + and K + channels but contributed modestly to the kinetics of action potentials. Copyright © 2017 the American Physiological Society.

Advances in the characterization of InAs/GaSb superlattice infrared photodetectors

NASA Astrophysics Data System (ADS)

Wörl, A.; Daumer, V.; Hugger, T.; Kohn, N.; Luppold, W.; Müller, R.; Niemasz, J.; Rehm, R.; Rutz, F.; Schmidt, J.; Schmitz, J.; Stadelmann, T.; Wauro, M.

2016-10-01

This paper reports on advances in the electro-optical characterization of InAs/GaSb short-period superlattice infrared photodetectors with cut-off wavelengths in the mid-wavelength and long-wavelength infrared ranges. To facilitate in-line monitoring of the electro-optical device performance at different processing stages we have integrated a semi-automated cryogenic wafer prober in our process line. The prober is configured for measuring current-voltage characteristics of individual photodiodes at 77 K. We employ it to compile a spatial map of the dark current density of a superlattice sample with a cut-off wavelength around 5 μm patterned into a regular array of 1760 quadratic mesa diodes with a pitch of 370 μm and side lengths varying from 60 to 350 μm. The different perimeter-to-area ratios make it possible to separate bulk current from sidewall current contributions. We find a sidewall contribution to the dark current of 1.2×10-11 A/cm and a corrected bulk dark current density of 1.1×10-7 A/cm2, both at 200 mV reverse bias voltage. An automated data analysis framework can extract bulk and sidewall current contributions for various subsets of the test device grid. With a suitable periodic arrangement of test diode sizes, the spatial distribution of the individual contributions can thus be investigated. We found a relatively homogeneous distribution of both bulk dark current density and sidewall current contribution across the sample. With the help of an improved capacitance-voltage measurement setup developed to complement this technique a residual carrier concentration of 1.3×1015 cm-3 is obtained. The work is motivated by research into high performance superlattice array sensors with demanding processing requirements. A novel long-wavelength infrared imager based on a heterojunction concept is presented as an example for this work. It achieves a noise equivalent temperature difference below 30 mK for realistic operating conditions.

The Role of Phonological versus Morphological Skills in the Development of Arabic Spelling: An Intervention Study.

PubMed

Taha, Haitham; Saiegh-Haddad, Elinor

2016-06-01

The current study investigated the contribution of two linguistic intervention programs, phonological and morphological to the development of word spelling among skilled and poor native Arabic readers, in three grades: second, fourth and sixth. The participants were assigned to three experimental groups: morphological intervention, phonological intervention and a non-intervention control group. Phonological awareness, morphological awareness, and spelling abilities were tested before and after the intervention. Participants from both linguistic intervention programs and in all grades made significant progress in linguistic awareness and spelling after the intervention. The results showed that both intervention programs were successful in promoting children's spelling skills in both groups. Also, older poor readers showed a stronger response to the morphological intervention than the older skilled readers. A transfer effect was found with the phonological training contributing to the morphological skills and vice versa. The results of the current study were discussed in the light of developmental and psycholinguistic views of spelling acquisition as well as the characteristics of Arabic language and orthography.

The contribution of smoking to inequalities in mortality by education varies over time and by sex: two national cohort studies, 1981-84 and 1996-99.

PubMed

Blakely, Tony; Wilson, Nick

2005-10-01

The contributions of tobacco smoking to overall mortality and socioeconomic inequalities in mortality vary between populations and over time. We determined how these contributions varied by sex and over time in two national New Zealand cohort studies. Poisson regression and modelling were conducted on linked census-mortality cohorts for people aged 45-74 years in 1981-84 and 1996-99 (2.0 and 2.7 million person-years, respectively). Contribution to socioeconomic inequalities in mortality. Adjusting for current and former smoking reduced the all-cause mortality rate ratios for men with nil educational qualifications compared with men with post-school qualifications from 1.34 to 1.29 in 1981-84 and from 1.31 to 1.25 in 1996-99, or 16 and 21% reductions in relative inequalities. Equivalent results for women were 1.42-1.41 in 1981-84 and 1.42-1.37 in 1996-99, or 3 and 11% reductions in relative inequalities. Contribution to overall mortality. Using 1996-99 data, we estimated that if all current smokers quit and became ex-smokers, mortality rates would reduce by 11% for men and 5% for women. If everyone was a never smoker (i.e. a historically smoke-free society), mortality rates would have been 26% lower for men and 25% lower for women. The contribution of smoking to educational inequalities in mortality was greater for males, and increased over time for both males and females, reflecting the historically differential phasing of the tobacco epidemic by sex and socioeconomic position. Complete cessation of smoking in contemporary New Zealand would reduce both overall mortality and educational inequalities in mortality.

Anxious and Depressive Symptomatology Among Male Youth: The Joint and Interactive Contribution of Temperament and Executive Functioning

PubMed Central

Shishido, Yuri; Latzman, Natasha E.; Clark, Lee Anna

2018-01-01

Few studies have investigated the combined effects of temperament and executive functioning (EF) on anxious and depressive symptomatology in youth. The current study is the first to investigate the joint and interactive contribution of mother- and youth self-reported affective dimensions of temperament and EF to the explanation of anxious and depressive symptomatology. Participants included 174 adolescent males (Mage = 13.6 ± 1.35). Results confirmed the joint and interactive contribution of temperament in the explanation of anxious and depressive symptomatology. Further, EF contributed to the explanation of anxious/depressive symptomatology via interaction with youth-, but not mother-reported, temperament; it was not a unique predictor. Results support the need to consider both affective dimensions of temperament and EF in etiological models of anxious and depressive symptomatology, which has implications for identifying at-risk youth and developing early intervention and targeted problem-specific prevention programs. PMID:26754748

Anxious and Depressive Symptomatology Among Male Youth: The Joint and Interactive Contribution of Temperament and Executive Functioning.

PubMed

Latzman, Robert D; Shishido, Yuri; Latzman, Natasha E; Clark, Lee Anna

2016-12-01

Few studies have investigated the combined effects of temperament and executive functioning (EF) on anxious and depressive symptomatology in youth. The current study is the first to investigate the joint and interactive contribution of mother- and youth self-reported affective dimensions of temperament and EF to the explanation of anxious and depressive symptomatology. Participants included 174 adolescent males (M age  = 13.6 ± 1.35). Results confirmed the joint and interactive contribution of temperament in the explanation of anxious and depressive symptomatology. Further, EF contributed to the explanation of anxious/depressive symptomatology via interaction with youth-, but not mother-reported, temperament; it was not a unique predictor. Results support the need to consider both affective dimensions of temperament and EF in etiological models of anxious and depressive symptomatology, which has implications for identifying at-risk youth and developing early intervention and targeted problem-specific prevention programs.

Etiology of Triarchic Psychopathy Dimensions in Chimpanzees (Pan troglodytes)

PubMed Central

Latzman, Robert D.; Patrick, Christopher J.; Freeman, Hani J.; Schapiro, Steven J.; Hopkins, William D.

2016-01-01

The current study undertook analyses of genealogical data from a sample of 178 socially-housed chimpanzees (Pan troglodytes) with well-documented pedigrees, to clarify the etiologic bases of triarchic psychopathy dimensions and the influence of early social rearing experiences. Whereas biometric analyses for the full sample indicated significant heritability for the boldness dimension of psychopathy only, heritability estimates varied by early rearing, with all three triarchic dimensions showing significant heritabilities among mother-reared but not nursery-reared apes. For mother-reared apes, both genes and environment contributed to covariance between meanness and disinhibition, whereas environment contributed mainly to covariation between these dimensions and boldness. Results indicate contributions of both genes and environment to psychopathic tendencies, with an important role for early-rearing in their relative contributions to distinct phenotypic subdimensions. In conjunction with findings from human studies, results provide valuable insights into core biobehavioral processes relevant to psychological illness and health. PMID:28503367

SIMBIOS Project

NASA Technical Reports Server (NTRS)

Fargion, Giulietta S.; McClain, Charles R.

2002-01-01

The purpose of this technical report is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, NASA Research Announcement (NRA) research status, satellite data processing, data product validation, and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project. The SIMBIOS Science Team Principal Investigators' (PIs) original contributions to this report are in chapters four and above. The purpose of these contributions is to describe the current research status of the SIMBIOS-NRA-96 funded research. The contributions are published as submitted, with the exception of minor edits to correct obvious grammatical or clerical errors.

Transport coefficients of Dirac ferromagnet: Effects of vertex corrections

NASA Astrophysics Data System (ADS)

Fujimoto, Junji

2018-03-01

As a strongly spin-orbit-coupled metallic model with ferromagnetism, we have considered an extended Stoner model to the relativistic regime, named Dirac ferromagnet in three dimensions. In a previous paper [J. Fujimoto and H. Kohno, Phys. Rev. B 90, 214418 (2014), 10.1103/PhysRevB.90.214418], we studied the transport properties giving rise to the anisotropic magnetoresistance (AMR) and the anomalous Hall effect (AHE) with the impurity potential being taken into account only as the self-energy. The effects of the vertex corrections (VCs) to AMR and AHE are reported in this paper. AMR is found not to change quantitatively when the VCs are considered, although the transport lifetime is different from the one-electron lifetime and the charge current includes additional contributions from the correlation with spin currents. The side-jump and the skew-scattering contributions to AHE are also calculated. The skew-scattering contribution is dominant in the clean case as can be seen in the spin Hall effect in the nonmagnetic Dirac electron system.

Actinide Solubility and Speciation in the WIPP [PowerPoint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reed, Donald T.

2015-11-02

The presentation begins with the role and need for nuclear repositories (overall concept, international updates (Sweden, Finland, France, China), US approach and current status), then moves on to the WIPP TRU repository concept (design, current status--safety incidents of February 5 and 14, 2014, path forward), and finally considers the WIPP safety case: dissolved actinide concentrations (overall approach, oxidation state distribution and redox control, solubility of actinides, colloidal contribution and microbial effects). The following conclusions are set forth: (1) International programs are moving forward, but at a very slow and somewhat sporadic pace. (2) In the United States, the Salt repositorymore » concept, from the perspective of the long-term safety case, remains a viable option for nuclear waste management despite the current operational issues/concerns. (3) Current model/PA prediction (WIPP example) are built on redundant conservatisms. These conservatisms are being addressed in the ongoing and future research to fill existing data gaps--redox control of plutonium by Fe(0, II), thorium (analog) solubility studies in simulated brine, contribution of intrinsic and biocolloids to the mobile concentration, and clarification of microbial ecology and effects.« less

Modeling of the coupled magnetospheric and neutral wind dynamos

NASA Technical Reports Server (NTRS)

Thayer, Jeffrey P.

1994-01-01

This report summarizes the progress made in the first year of NASA Grant No. NAGW-3508 entitled 'Modeling of the Coupled Magnetospheric and Neutral Wind Dynamos.' The approach taken has been to impose magnetospheric boundary conditions with either pure voltage or current characteristics and solve the neutral wind dynamo equation under these conditions. The imposed boundary conditions determine whether the neutral wind dynamo will contribute to the high-latitude current system or the electric potential. The semi-annual technical report, dated December 15, 1993, provides further detail describing the scientific and numerical approach of the project. The numerical development has progressed and the dynamo solution for the case when the magnetosphere acts as a voltage source has been evaluated completely using spectral techniques. The simulation provides the field-aligned current distribution at high latitudes due to the neutral wind dynamo. A number of geophysical conditions can be simulated to evaluate the importance of the neutral wind dynamo contribution to the field-aligned current system. On average, field-aligned currents generated by the neutral wind dynamo contributed as much as 30 percent to the large-scale field-aligned current system driven by the magnetosphere. A term analysis of the high-latitude neutral wind dynamo equation describing the field aligned current distribution has also been developed to illustrate the important contributing factors involved in the process. The case describing the neutral dynamo response for a magnetosphere acting as a pure current generator requires the existing spectral code to be extended to a pseudo-spectral method and is currently under development.

The evolution of ring current ion energy density and energy content during geomagnetic storms based on Van Allen Probes measurements

DOE PAGES

Zhao, H.; Li, X.; Baker, D. N.; ...

2015-08-25

Enabled by the comprehensive measurements from the Magnetic Electron Ion Spectrometer (MagEIS), Helium Oxygen Proton Electron mass spectrometer (HOPE), and Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) instruments onboard Van Allen Probes in the heart of the radiation belt, the relative contributions of ions with different energies and species to the ring current energy density and their dependence on the phases of geomagnetic storms are quantified. The results show that lower energy (<50 keV) protons enhance much more often and also decay much faster than higher-energy protons. During the storm main phase, ions with energies <50 keV contribute moremore » significantly to the ring current than those with higher energies; while the higher-energy protons dominate during the recovery phase and quiet times. The enhancements of higher-energy proton fluxes as well as energy content generally occur later than those of lower energy protons, which could be due to the inward radial diffusion. For the 29 March 2013 storm we investigated in detail that the contribution from O + is ~25% of the ring current energy content during the main phase and the majority of that comes from <50 keV O +. This indicates that even during moderate geomagnetic storms the ionosphere is still an important contributor to the ring current ions. Using the Dessler-Parker-Sckopke relation, the contributions of ring current particles to the magnetic field depression during this geomagnetic storm are also calculated. In conclusion, the results show that the measured ring current ions contribute about half of the Dst depression.« less

The evolution of ring current ion energy density and energy content during geomagnetic storms based on Van Allen Probes measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, H.; Li, X.; Baker, D. N.

Enabled by the comprehensive measurements from the Magnetic Electron Ion Spectrometer (MagEIS), Helium Oxygen Proton Electron mass spectrometer (HOPE), and Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) instruments onboard Van Allen Probes in the heart of the radiation belt, the relative contributions of ions with different energies and species to the ring current energy density and their dependence on the phases of geomagnetic storms are quantified. The results show that lower energy (<50 keV) protons enhance much more often and also decay much faster than higher-energy protons. During the storm main phase, ions with energies <50 keV contribute moremore » significantly to the ring current than those with higher energies; while the higher-energy protons dominate during the recovery phase and quiet times. The enhancements of higher-energy proton fluxes as well as energy content generally occur later than those of lower energy protons, which could be due to the inward radial diffusion. For the 29 March 2013 storm we investigated in detail that the contribution from O + is ~25% of the ring current energy content during the main phase and the majority of that comes from <50 keV O +. This indicates that even during moderate geomagnetic storms the ionosphere is still an important contributor to the ring current ions. Using the Dessler-Parker-Sckopke relation, the contributions of ring current particles to the magnetic field depression during this geomagnetic storm are also calculated. In conclusion, the results show that the measured ring current ions contribute about half of the Dst depression.« less

Investigating the decision-making processes that contribute to impaired driving.

DOT National Transportation Integrated Search

2015-08-01

Alcohol-impaired (AI) driving continues to cause a disproportionate number of fatalities within the college and : young adult populations, indicating optimal prevention programs for AI driving have yet to be developed. The : current study tested the ...

The Contributions of the WIYN Observatory to Undergraduate Education

NASA Astrophysics Data System (ADS)

Hooper, Eric; Consortium, WIYN

2014-01-01

Over its nearly 20 year history the WIYN Observatory has provided crucial data for numerous undergraduate research projects at the partner institutions (University of Wisconsin-Madison, Indiana University, and Yale University) plus others who access the telescope via national time from NOAO. WIYN and its instruments have served both undergraduates who are local to each institution, as well as those who have a temporary tenure as Research Experience for Undergraduates (REU) students. The topics of this work range widely, and only a few examples are listed here. Numerous studies of stars have been undertaken by undergraduates, from rotation velocities of pre-main sequence stars (Rhode et al.) to dynamical heating mechanisms in open clusters (Friel et al.). Extragalactic investigations range from a study of cold ISM in galaxies near the centers of rich clusters (Gallagher & Hooper, et al.) to the stellar populations of post-starburst galaxies hosting low-level AGN (Wolf & Hooper, et al.). Students have made wide use of WIYN's long established suite of facility instruments, which currently includes the Hydra multi-object fiber spectrograph, the SparsePak integral field unit fiber spectrograph, and the WHIRC near-infrared imager. A current undergraduate is a key player in final laboratory testing of two new integral field units that will come to WIYN soon. Finally, the new large format imager pODI currently is in science operation, soon to be followed by an upgrade to nearly four times the current imaging area, a powerful tool that will join the others in contributing to undergraduate research and education. This presentation is a continuation of the overview of WIYN contributions to education that began with a discussion of graduate education at the Indianapolis AAS (Hooper, AAS Meeting #222, #214.23).

The PAKs come of age

PubMed Central

2012-01-01

Protein kinases are versatile signaling molecules that are involved in the regulation most physiological responses. The p21-activated kinases (PAKs) can be activated directly by the small GTPases Rac and Cdc42 and are among the best characterized downstream effectors of these Rho proteins. The structure, substrate specificity and functional role of PAKS are evolutionarily conserved from protozoa to mammals. Vertebrate PAKs are particularly important for cytoskeletal remodeling and focal adhesion assembly, thereby contributing to dynamic processes such as cell migration and synaptic plasticity. This issue of Cellular Logistics focuses on the PAK family of kinases, with ten reviews written by researchers currently working in the field. Here in this introductory overview we highlight some of the most interesting recent discoveries regarding PAK biochemistry and biology. The reviews in this issue cover a range of topics including the atomic structures of PAK1 and PAK4, their role in animals as assessed by knockout studies, and how PAKs are likely to contribute to cancer and neurodegenerative diseases. The promise remains that PAK inhibitors will emerge that validate current pre-clinical studies suggesting that blocking PAK activity will positively contribute to human health. PMID:23125949

A squid-based beam current monitor for FAIR/CRYRING

NASA Astrophysics Data System (ADS)

Geithner, Rene; Kurian, Febin; Reeg, Hansjörg; Schwickert, Marcus; Neubert, Ralf; Seidel, Paul; Stöhlker, Thomas

2015-11-01

A SQUID-based beam current monitor was developed for the upcoming FAIR-Project, providing a non-destructive online monitoring of the beam currents in the nA-range. The cryogenic current comparator (CCC) was optimized for lowest possible noise-limited current resolution together with a high system bandwidth. This CCC is foreseen to be installed in the CRYRING facility (CRYRING@ESR: A study group report www.gsi.de/fileadmin/SPARC/documents/Cryring/ReportCryring_40ESR.PDF), working as a test bench for FAIR. In this contribution we present results of the completed CCC for FAIR/CRYRING and also arrangements that have been done for the installation of the CCC at CRYRING, regarding the cryostat design.

Examining differences in drinking patterns among Jewish and Arab university students in Israel.

PubMed

Sznitman, Sharon R; Bord, Shiran; Elias, Wafa; Gesser-Edelsburg, Anat; Shiftan, Yoram; Baron-Epel, Orna

2015-01-01

Worldwide there is a dearth of studies examining drinking patterns in Arabs and how these compare to other populations. The few studies that exist have suggested distinct drinking patterns in Arabs, with not only high rates of abstinence but also high rates of heavy drinking among current drinkers. No studies have yet examined potential socio-cognitive mechanisms that may contribute to this distinct drinking pattern. Israel represents a unique and valuable resource for studying Arab population drinking patterns because Israeli Arabs are nonimmigrants living in areas where exposure to Western lifestyles, including alcohol consumption, is prevalent. The current study was set out to examine differences in alcohol consumption in a convenience sample of 1310 Jewish and Arab students from Israeli universities and colleges and to explore alcohol expectancies as potential mediators of ethno-religious differences. Logistic regressions were used to produce odds ratios and 95% confidence intervals to test differences between Jewish and Arab students on binary outcomes (lifetime, last month, and heavy drinking). Mediation of ethno-religious differences by alcohol expectancies was tested with bootstrapping procedures. Results show that while Israeli Arab students tend to be more likely to abstain from alcohol than Israeli Jewish students, among current drinkers, Israeli Arab students are at a particular high risk of heavy drinking. Results also show that this is partly mediated by the expectancy that alcohol only influences the drinker at high levels of intake. The current study confirms distinct Arab drinking patterns found in previous studies. The present study is the first demonstration that drinking expectations mediate ethno-religious differences in heavy drinking among Israeli Arabs and Jews. This work contributes to the understanding of ethno-religious group differences in harmful drinking, potentially informing future etiologic research and public health interventions aimed at reducing alcohol-related harm.

Max Kreuzer's contributions to the study of Calabi-Yau manifolds

NASA Astrophysics Data System (ADS)

Candelas, Philip

2013-10-01

Any account of Max's career in physics must be bound up with the history of the study of Calabi-Yau manifolds, to which Max contributed at many levels. There were many currents in this study and work was not done in isolation. Work often advances through a series of challenges, and in reaction to other work. Insofar as I have myself been involved in some of these researches it is inevitable that I will have to recall some of these projects that were, at times, inextricably linked with Max's work. For this deficiency of the account let me make this single apology...

Oxytocin receptor and vasopressin receptor 1a genes are respectively associated with emotional and cognitive empathy.

PubMed

Uzefovsky, F; Shalev, I; Israel, S; Edelman, S; Raz, Y; Mankuta, D; Knafo-Noam, A; Ebstein, R P

2015-01-01

Empathy is the ability to recognize and share in the emotions of others. It can be considered a multifaceted concept with cognitive and emotional aspects. Little is known regarding the underlying neurochemistry of empathy and in the current study we used a neurogenetic approach to explore possible brain neurotransmitter pathways contributing to cognitive and emotional empathy. Both the oxytocin receptor (OXTR) and the arginine vasopressin receptor 1a (AVPR1a) genes contribute to social cognition in both animals and humans and hence are prominent candidates for contributing to empathy. The following research examined the associations between polymorphisms in these two genes and individual differences in emotional and cognitive empathy in a sample of 367 young adults. Intriguingly, we found that emotional empathy was associated solely with OXTR, whereas cognitive empathy was associated solely with AVPR1a. Moreover, no interaction was observed between the two genes and measures of empathy. The current findings contribute to our understanding of the distinct neurogenetic pathways involved in cognitive and emotional empathy and underscore the pervasive role of both oxytocin and vasopressin in modulating human emotions. Copyright © 2014 Elsevier Inc. All rights reserved.

Evolution of quantitative methods for the study and management of avian populations: on the importance of individual contributions

USGS Publications Warehouse

Nichols, J.D.

2004-01-01

The EURING meetings and the scientists who have attended them have contributed substantially to the growth of knowledge in the field of estimating parameters of animal populations. The contributions of David R. Anderson to process modeling, parameter estimation and decision analysis are briefly reviewed. Metrics are considered for assessing individual contributions to a field of inquiry, and it is concluded that Anderson’s contributions have been substantial. Important characteristics of Anderson and his career are the ability to identify and focus on important topics, the premium placed on dissemination of new methods to prospective users, the ability to assemble teams of complementary researchers, and the innovation and vision that characterized so much of his work. The paper concludes with a list of interesting current research topics for consideration by EURING participants.

Self- and Peer-Assessment: Evidence from the Accounting and Finance Discipline

ERIC Educational Resources Information Center

Hassan, Omaima A. G.; Fox, Alison; Hannah, Gwen

2014-01-01

Self- and peer-assessment of student work is an area that is under-researched in the accounting education literature, although the subject area of study seems to influence the results obtained in prior studies. The current study contributes to the literature by examining the accuracy and construct validity of self- and peer-assessment by…

The Influence of Birth Country on Selection of Conference Destination--Employing Natural Language Processing

ERIC Educational Resources Information Center

Davidovitch, Nitza; Eckhaus, Eyal

2018-01-01

This study deals with immigrant scientists integrated in academia in Israel. Studies on the subject indicate the contribution of immigrant scientists to research. The current study focuses on the influence of scientists' birth country on selecting destinations for academic conferences, as well as on the influence of one's native language on the…

Ideas of I. M. Sechenov in aviation and space medicine

NASA Technical Reports Server (NTRS)

Gazenko, O. G.; Kovalenko, Y. A.

1980-01-01

The contributions I. M. Sechenov (19th century) made to modern physiology are described, including his studies on gases in the blood (O2 and CO2), and how these studies were the basic building blocks of current efforts in aviation and space medicine. Sechenov also studied hypokinesia, which is becoming important in long duration space flights.

Observation of instability-induced current redistribution in a spherical-torus plasma.

PubMed

Menard, J E; Bell, R E; Gates, D A; Kaye, S M; LeBlanc, B P; Levinton, F M; Medley, S S; Sabbagh, S A; Stutman, D; Tritz, K; Yuh, H

2006-09-01

A motional Stark effect diagnostic has been utilized to reconstruct the parallel current density profile in a spherical-torus plasma for the first time. The measured current profile compares favorably with neoclassical theory when no large-scale magnetohydrodynamic instabilities are present in the plasma. However, a current profile anomaly is observed during saturated interchange-type instability activity. This apparent anomaly can be explained by redistribution of neutral beam injection current drive and represents the first observation of interchange-type instabilities causing such redistribution. The associated current profile modifications contribute to sustaining the central safety factor above unity for over five resistive diffusion times, and similar processes may contribute to improved operational scenarios proposed for ITER.

Southern montane populations did not contribute to the recolonization of West Siberian Plain by Siberian larch (Larix sibirica): a range-wide analysis of cytoplasmic markers.

PubMed

Semerikov, Vladimir L; Semerikova, Svetlana A; Polezhaeva, Maria A; Kosintsev, Pavel A; Lascoux, Martin

2013-10-01

While many species were confined to southern latitudes during the last glaciations, there has lately been mounting evidence that some of the most cold-tolerant species were actually able to survive close to the ice sheets. The contribution of these higher latitude outposts to the main recolonization thrust remains, however, untested. In the present study, we use the first range-wide survey of genetic diversity at cytoplasmic markers in Siberian larch (Larix sibirica; four mitochondrial (mt) DNA loci and five chloroplast (cp) DNA SSR loci) to (i) assess the relative contributions of southern and central areas to the current L. sibirica distribution range; and (ii) date the last major population expansion in both L. sibirica and adjacent Larix species. The geographic distribution of cpDNA variation was uninformative, but that of mitotypes clearly indicates that the southernmost populations, located in Mongolia and the Tien-Shan and Sayan Mountain ranges, had a very limited contribution to the current populations of the central and northern parts of the range. It also suggests that the contribution of the high latitude cryptic refugia was geographically limited and that most of the current West Siberian Plain larch populations likely originated in the foothills of the Sayan Mountains. Interestingly, the main population expansion detected through Approximate Bayesian Computation (ABC) in all four larch species investigated here pre-dates the LGM, with a mode in a range of 220,000-1,340,000 years BP. Hence, L. sibirica, like other major conifer species of the boreal forest, was strongly affected by climatic events pre-dating the Last Glacial Maximum. © 2013 John Wiley & Sons Ltd.

Family Violence and Children’s Behavior Problems: Independent Contributions of Intimate Partner and Child-Directed Physical Aggression

PubMed Central

Gustafsson, Hanna C.; Barnett, Melissa A.; Towe-Goodman, Nissa R.; Mills-Koonce, W. Roger; Cox, Martha J.

2014-01-01

Using data from a diverse sample of 581 families living in predominantly low-income, rural communities, the current study sought to investigate the longitudinal associations among father-perpetrated intimate partner violence (IPV) and child-directed physical aggression perpetrated by the mother. The unique contributions of each of these types of family violence on children’s behavioral problems at school entry were also examined. Results confirm bidirectional associations between father-perpetrated IPV and maternal physical aggression directed toward the child, and indicate that both types of physical aggression contribute to child behavior problems at school entry. PMID:25431522

A novel approach for measuring residential socioeconomic factors associated with cardiovascular and metabolic health

EPA Science Inventory

Individual-level characteristics, including socioeconomic status, have been associated with poor metabolic and cardiovascular health; however, residential area-level characteristics may also independently contribute to health status. In the current study, we used hierarchical clu...

Study of Magnetospheric Currents and Resultant Surface Magnetic Variations.

DTIC Science & Technology

1980-04-17

compressed as indicated by solar -wind data, automatically injected a ring current with a strength consistent with the observed Dst. The computed inner...Fig!ire 2?; bottoim panal of Figure 5_. Agreement is very acceptahle. The model overestimated the maximum depression of RX, but by a factor that is well...Contributed Papers Presented at the Solar -Terrestrial Physics Symposium, Innsbruck, 1978. Harel, M., R. A. Wolf, P. H. Reiff and M. Siiddy, Computer

A Typology of Burnout among Korean Teachers

ERIC Educational Resources Information Center

Jin, Yuan Ying; Noh, Hyunkyung; Shin, Hyojung; Lee, Sang Min

2015-01-01

The current study aims to identify a typology of burnout in Korean school teachers and also examines the discriminant variables that contribute to burnout group's differences. A total of 345 Korean school teachers in middle and high school participated in this study. Each participant filled out a Korean version of the Maslach Burnout…

Does the New Digital Generation of Learners Exist? A Qualitative Study

ERIC Educational Resources Information Center

Sanchez, Jaime; Salinas, Alvaro; Contreras, David; Meyer, Eduardo

2011-01-01

This paper seeks to contribute to the discussion on the current generation of students and their relationship to technology, providing qualitative, empirical information obtained in the Chilean context. The study analyses and discusses the ideas regarding the emergence of a new generation of learners, or digital natives, as characterised by…

Implicit Beliefs about Emotion Regulation and Their Relations with Emotional Experiences among Chinese Adolescents

ERIC Educational Resources Information Center

Deng, Xinmei; Sang, Biao; Chen, Xinyin

2017-01-01

There is growing interest in understanding how beliefs about emotion regulation are related to individual emotional experiences. Extant studies have mainly focused on explicit beliefs about emotion regulation among individuals in Western societies. The current study examined implicit emotion regulation and explored their contributions to emotional…

Achievement Goals, Learning Strategies and Instrumental Performance

ERIC Educational Resources Information Center

Nielsen, Siw Graabraek

2008-01-01

The current study is a survey of the achievement goals of music students and the manner in which their strategies and instrumental performance relate to these goals. In the context of advanced instrumental learning, the rationale for the present study was to contribute to the literature on motivation in music students, and thereby, help teachers…

How Do Principals Respond to Charter School Competition? Research Brief

ERIC Educational Resources Information Center

Cannata, Marisa

2011-01-01

The current study from the National Center on School Choice contributes to the research by exploring the factors that affect principals' perceptions of charter school competition and the extent to which their leadership behavior may change in response. Central research questions of the study were: (1) How do principals perceive the competition…

An Exploratory Study of Problem Gambling on Casino versus Non-Casino Electronic Gaming Machines

ERIC Educational Resources Information Center

Clarke, Dave; Pulford, Justin; Bellringer, Maria; Abbott, Max; Hodgins, David C.

2012-01-01

Electronic gaming machines (EGMs) have been frequently associated with problem gambling. Little research has compared the relative contribution of casino EGMs versus non-casino EGMs on current problem gambling, after controlling for demographic factors and gambling behaviour. Our exploratory study obtained data from questionnaires administered to…

Human Securitability: A Participatory Action Research Study Involving Novice Teachers and Youngsters

ERIC Educational Resources Information Center

Kravale-Paulina, Marite; Olehnovica, Eridiana

2015-01-01

Civic participation, initiative and interest in current events can bridge the alienation felt towards national and municipal institutions, thereby enabling individuals to improve their quality of life and contribute to all-round sustainable development of their resident state. This paper reports on a participatory action research study into civic…

Ontogeny of Emotional and Behavioral Problems in a Low-Income, Mexican American Sample

ERIC Educational Resources Information Center

Lin, Betty; Crnic, Keith A.; Luecken, Linda J.; Gonzales, Nancy A.

2017-01-01

Clinically meaningful behavior problems are thought to be present beginning in the early toddler years, yet few studies have investigated correlates of behavior problems assessed before age 2 years. The current study investigated the direct and interactive contributions of early infant and caregiver characteristics thought to play an important…

Paternal Involvement and Child Sleep: A Look beyond Infancy

ERIC Educational Resources Information Center

Bernier, Annie; Tétreault, Émilie; Bélanger, Marie-Ève; Carrier, Julie

2017-01-01

While maternal influences on young children's sleep are increasingly documented, the study of paternal contributions to this important sphere of child functioning is only just beginning. In addition, much of this emerging research has focused on infancy only or has relied on parental reports of child sleep. The current study aimed to examine the…

Romantic Partners' Contribution to the Continuity of Male and Female Delinquent and Violent Behavior

ERIC Educational Resources Information Center

Herrera, Veronica M.; Wiersma, Jacquelyn D.; Cleveland, H. Harrington

2011-01-01

Using data drawn from the National Longitudinal Study of Adolescent Health (Add Health), this study examined males' and females' criminality in young adulthood with models that considered the associations of both their own past delinquency and their current partners' criminality. Specific models considered the main effects of both previous…

Academic Achievement among Recently Arrived Chinese Adolescent Migrants: The Role of Social Support, School Belonging, and Acculturative Stress

ERIC Educational Resources Information Center

Ho, Ngai Kwan Nicole; Schweitzer, Robert D.; Khawaja, Nigar G.

2017-01-01

Factors contributing to academic achievement among recently arrived Chinese adolescents in Australia remain relatively underexplored. Previous studies focused on Asian migrants, including Chinese, but did not distinguish Chinese from other Asian migrants. The current study specifically looks at Chinese migrants who have recently arrived, as…

Coping Styles and Sex Differences in Depressive Symptoms and Delinquent Behavior

ERIC Educational Resources Information Center

Kort-Butler, Lisa A.

2009-01-01

Building on research that links gender to differences in well-being and differences in stress exposure and vulnerability, the current study examines how coping styles are gendered in ways that may contribute to sex differences in depressive symptoms and delinquent behavior. The study disaggregates stress measures to reflect gender differences in…

Investigating Students' Perceptions of Graduate Learning Outcomes in Mathematics

ERIC Educational Resources Information Center

King, Deborah; Varsavsky, Cristina; Belward, Shaun; Matthews, Kelly

2017-01-01

The purpose of this study is to explore the perceptions mathematics students have of the knowledge and skills they develop throughout their programme of study. It addresses current concerns about the employability of mathematics graduates by contributing much needed insight into how degree programmes are developing broader learning outcomes for…

Compassion: A Qualitative Instrumental Case Study on Student Retention

ERIC Educational Resources Information Center

Shedletsky, Nikki

2017-01-01

This qualitative case study examined the past and current student retention literature and research in order to fill voids in the literature and knowledge and contribute to increasing retention of more students by understanding Spalding University's culture and how they make it work to serve students. Data was collected from surveys, interviews…

The Role of Education in Peace-Building in the African Great Lakes Region: Educators' Perspectives

ERIC Educational Resources Information Center

Ndura-Ouedraogo, Elavie

2009-01-01

This article discusses the findings from a qualitative study which examined educators' perceptions of their contributions to the quest for sustainable peace in Burundi and the African Great Lakes region. The study looked at how educators representing different ethnic backgrounds, academic preparation, and currently employed at different levels…

Contributions of poroelastic-wave potentials to seismoelectromagnetic wavefields and validity of the quasi-static calculation: a view from a borehole model

NASA Astrophysics Data System (ADS)

Guan, Wei; Shi, Peng; Hu, Hengshan

2018-01-01

In this study, we theoretically analyse the contributions of the four poroelastic-wave potentials to seismoelectromagnetic (SEM) wavefields, verify the validity of the quasi-static calculation of the electric field and provide a method to calculate the magnetic field by using the curl-free electric field. Calculations show that both the fast and slow P waves and the SH and SV waves have non-negligible contributions to the SEM fields. The S waves have indirect contribution to the electric field through the EM conversion from the magnetic field, although the direct contribution due to streaming current is negligible if EM wavenumbers are much smaller than those of the S waves. The P waves have indirect contribution to the magnetic field through EM conversion from the electric field, although the direct contribution is absent. The quasi-static calculation of the electric field is practicable since it is normally satisfied in reality that the EM wavenumbers are much smaller than those of poroelastic waves. While the direct contribution of the S waves and the higher-order EM conversions are ignored, the first-order EM conversion from the S-wave-induced magnetic field is reserved through the continuity of the electric-current density. To calculate the magnetic field on this basis, we separate the quasi-static electric field into a rotational and an irrotational part. The magnetic-field solutions are derived through Hertz vectors in which the coefficients of the magnetic Hertz vector are determined from the magnetic-field continuities and those of the electric Hertz vector originate from the irrotational part of the quasi-static electric field.

Role of cold water and beta-effect in the formation of the East Korean Warm Current in the East/Japan Sea: a numerical experiment

NASA Astrophysics Data System (ADS)

Kim, Yong-Yub; Cho, Yang-Ki; Kim, Young Ho

2018-06-01

The contributions of bottom cold water and planetary β-effect to the formation of the East Korean Warm Current (EKWC), the western boundary current in the East/Japan Sea (EJS), were evaluated using an idealized three-dimensional numerical model. The model results suggest that the bottom cold water and, to a lesser extent, the planetary β-effect both contribute to the formation of the EKWC. The cold water functions as the bottom of the upper layer, to control the EKWC via conservation of potential vorticity. It is known that cold waters, such as the North Korean Cold Water and Korea Strait Bottom Cold Water often observed during summer along the southwestern coast of the EJS, originate from the winter convection in the northern area. Observational studies consistently show that the EKWC strengthens in summer when the cold water extends further south along the western boundary.

The contribution of interindividual factors to variability of response in transcranial direct current stimulation studies

PubMed Central

Li, Lucia M.; Uehara, Kazumasa; Hanakawa, Takashi

2015-01-01

There has been an explosion of research using transcranial direct current stimulation (tDCS) for investigating and modulating human cognitive and motor function in healthy populations. It has also been used in many studies seeking to improve deficits in disease populations. With the slew of studies reporting “promising results” for everything from motor recovery after stroke to boosting memory function, one could be easily seduced by the idea of tDCS being the next panacea for all neurological ills. However, huge variability exists in the reported effects of tDCS, with great variability in the effect sizes and even contradictory results reported. In this review, we consider the interindividual factors that may contribute to this variability. In particular, we discuss the importance of baseline neuronal state and features, anatomy, age and the inherent variability in the injured brain. We additionally consider how interindividual variability affects the results of motor-evoked potential (MEP) testing with transcranial magnetic stimulation (TMS), which, in turn, can lead to apparent variability in response to tDCS in motor studies. PMID:26029052

Epidemiological Studies to Support the Development of Next Generation Influenza Vaccines.

PubMed

Petrie, Joshua G; Gordon, Aubree

2018-03-26

The National Institute of Allergy and Infectious Diseases recently published a strategic plan for the development of a universal influenza vaccine. This plan focuses on improving understanding of influenza infection, the development of influenza immunity, and rational design of new vaccines. Epidemiological studies such as prospective, longitudinal cohort studies are essential to the completion of these objectives. In this review, we discuss the contributions of epidemiological studies to our current knowledge of vaccines and correlates of immunity, and how they can contribute to the development and evaluation of the next generation of influenza vaccines. These studies have been critical in monitoring the effectiveness of current influenza vaccines, identifying issues such as low vaccine effectiveness, reduced effectiveness among those who receive repeated vaccination, and issues related to egg adaptation during the manufacturing process. Epidemiological studies have also identified population-level correlates of protection that can inform the design and development of next generation influenza vaccines. Going forward, there is an enduring need for epidemiological studies to continue advancing knowledge of correlates of protection and the development of immunity, to evaluate and monitor the effectiveness of next generation influenza vaccines, and to inform recommendations for their use.

Job satisfaction in relation to energy resource consciousness and perceptions of energy utilization in selected Illinois manufacturing firms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haynes, T.S.

1986-01-01

This study was developed through a synthesis and review of literature and research related to the current status of job satisfaction, energy resources, and perceptions of how energy is utilized in the manufacturing work environment. This synthesis and review revolved around several proven contributing factors of job satisfaction, such as age, education, and challenge from work itself. Quality of work life programs and their components are discussed in relation to their impact on job satisfaction. The nature of energy resource utilization is traced back through history with an emphasis on the limitations of current resources and options for the future.more » The review highlights the current debate over what should be the future path of energy resource development. The concept of satisfaction of human needs is reviewed and related to job satisfaction and energy resources. The purpose of this research study was to contribute to the understanding of how perceptions of energy resources relate to job satisfaction. Results of the study indicated that there were no significant differences between an individual's energy resource consciousness and perceptions of energy utilization in the work place, energy resource consciousness and job satisfaction, and job satisfaction and perceptions of energy utilization in the workplace.« less

Jet behaviors and ejection mode recognition of electrohydrodynamic direct-write

NASA Astrophysics Data System (ADS)

Zheng, Jianyi; Zhang, Kai; Jiang, Jiaxin; Wang, Xiang; Li, Wenwang; Liu, Yifang; Liu, Juan; Zheng, Gaofeng

2018-01-01

By introducing image recognition and micro-current testing, jet behavior research was conducted, in which the real-time recognition of ejection mode was realized. To study the factors influencing ejection modes and the current variation trends under different modes, an Electrohydrodynamic Direct-Write (EDW) system with functions of current detection and ejection mode recognition was firstly built. Then a program was developed to recognize the jet modes. As the voltage applied to the metal tip increased, four jet ejection modes in EDW occurred: droplet ejection mode, Taylor cone ejection mode, retractive ejection mode and forked ejection mode. In this work, the corresponding relationship between the ejection modes and the effect on fiber deposition as well as current was studied. The real-time identification of ejection mode and detection of electrospinning current was realized. The results in this paper are contributed to enhancing the ejection stability, providing a good technical basis to produce continuous uniform nanofibers controllably.

The investigation of the cellular electrophysiological and antiarrhythmic effects of a novel selective sodium-calcium exchanger inhibitor, GYKB-6635, in canine and guinea-pig hearts.

PubMed

Geramipour, Amir; Kohajda, Zsófia; Corici, Claudia; Prorok, János; Szakonyi, Zsolt; Oravecz, Kinga; Márton, Zoltán; Nagy, Norbert; Tóth, András; Acsai, Károly; Virág, László; Varró, András; Jost, Norbert

2016-10-01

The sodium-calcium exchanger (NCX) is considered as the major transmembrane transport mechanism that controls Ca 2+ homeostasis. Its contribution to the cardiac repolarization has not yet been directly studied due to lack of specific inhibitors, so that an urgent need for more selective compounds. In this study, the electrophysiological effects of GYKB-6635, a novel NCX inhibitor, on the NCX, L-type calcium, and main repolarizing potassium currents as well as action potential (AP) parameters were investigated. Ion currents and AP recordings were investigated by applying the whole-cell patch clamp and standard microelectrode techniques in canine heart at 37 °C. Effects of GYKB-6635 were studied in ouabain-induced arrhythmias in isolated guinea-pig hearts. At a concentration of 1 μmol/L, GYKB significantly reduced both the inward and outward NCX currents (57% and 58%, respectively). Even at a high concentration (10 μmol/L), GYKB-6635 did not change the I CaL , the maximum rate of depolarization (dV/dt max ), the main repolarizing K + currents, and the main AP parameters. GYKB-6635 pre-treatment significantly delayed the time to the development of ventricular fibrillation (by about 18%). It is concluded that GYKB-6635 is a potent and highly selective inhibitor of the cardiac NCX and, in addition, it is suggested to also contribute to the prevention of DAD-based arrhythmias.

Modeling of the Coupled Magnetospheric and Neutral Wind Dynamos

NASA Technical Reports Server (NTRS)

Thayer, Jeffrey P.

1997-01-01

Over the past four years of funding, SRI, in collaboration with the University of Texas at Dallas, has been involved in assessing the influence of thermospheric neutral winds on the electric field and current systems at high latitudes. The initial direction of the project was to perform a set of numerical experiments concerning the contribution of the magnetospheric and neutral wind dynamo processes, under specific boundary conditions, to the polarization electric field and/or the field-aligned current distribution at high latitudes. To facilitate these numerical experiments we developed a numerical scheme that relied on using output from the NCAR Thermosphere-Ionosphere General Circulation Model (NCAR-TIGCM), expanding them in the form of spherical harmonics and solving the dynamo equations spectrally. Once initial calculations were completed, it was recognized that the neutral wind contribution could be significant but its actual contribution to the electric field or currents depended strongly on the generator properties of the magnetosphere. Solutions to this problem are not unique because of the unknown characteristics of the magnetospheric generator, therefore the focus was on two limiting cases. One limiting case was to consider the magnetosphere as a voltage generator delivering a fixed voltage to the high-latitude ionosphere and allowing for the neutral wind dynamo to contribute only to the current system. The second limiting case was to consider the magnetosphere as a current generator and allowing for the neutral wind dynamo to contribute only to the generation of polarization electric fields. This work was completed and presented at the l994 Fall AGU meeting. The direction of the project then shifted to applying the Poynting flux concept to the high-latitude ionosphere. This concept was more attractive as it evaluated the influence of neutral winds on the high-latitude electrodynamics without actually having to determine the generator characteristics of the magnetosphere. The influence of the neutral wind was then determined not by estimating how much electric potential or current density it provides, but by determining the contribution of the neutral wind to the net electromagnetic energy transferred between the ionosphere and magnetosphere. The estimate of the net electromagnetic energy transfer and the role of the neutral winds proves to be a more fundamental quantity in studies of magnetosphere- ionosphere coupling also showed that by using electric and magnetic field measurements from the HILAT satellite, the Poynting flux could be a measurable quantity from polar-orbiting, low- altitude spacecraft. Through collaboration with Dr. Heelis and others at UTD and their expertise of the electric field measurements on the DE-B satellite, an extensive analysis was planned to determine the Poynting flux from the DE-B measurements in combination with a modeling effort to help interpret the observations taking into account the coupled magnetosphere-ionosphere.

A novel approach to measuring residential socioeconomic factors associated with cardiovascular and metabolic health

EPA Science Inventory

Individual-level characteristics, including socioeconomic status, have been associated with poor metabolic and cardiovascular health; however, residential area-level characteristics may also independently contribute to health status. In the current study, we used a novel applica...

Effects of on-street parking on cyclist route choice and the operational behavior of cyclists and motorists.

DOT National Transportation Integrated Search

2009-04-01

Because of the serious societal, environmental, economic, and public health problems associated with motorized : transportation, there is increased interest in encouraging non-motorized modes of travel. The current study contributes toward this : obj...

Nutrient flux estimates in a tidal basin: A case study of Magdalena lagoon, Mexican Pacific coast

NASA Astrophysics Data System (ADS)

Zaytsev, Oleg; Cervantes-Duarte, Rafael

2018-07-01

Bahia Magdalena (BM), known for its high primary productivity, is one of the largest tidal lagoons on the Mexican Pacific coast of the Baja California Peninsula. BM is located in an area of active coastal upwelling and significant tides with a maximum range of about 2.4 m. Dissolved inorganic nutrients upwelled from the depths are transported by tidal water exchange into the lagoon, contributing to its fertilisation. To estimate the magnitude and mechanisms driving the tidal exchange of water and nutrients, field observations of the nutrient content were made in the inlet area and on the adjacent shelf during March 2003, December 2004 and June, August and November 2005. In March 2003, the research vessel El Puma carried out a complete hydrological study of the area using Seabird-19 CTD profiler. At the same time, a current meter with a tide gauge was installed in the BM inlet, and multiple measurements of currents were made on a section across the inlet with a SonTek hull-mounted Acoustic Doppler Current Profiler (ADCP). Field studies were complemented by numerical experiments with the hydrodynamic model ECOM 3D. Analysis of the currents in the inlet area, deriving from both the ADCP data and the numerical simulation, indicates that the water volume transported during a semidiurnal tidal cycle through the inlet varied from 0.3 km3 for neap tide to 0.82 km3 for spring tide. Net nitrate mass intakes to the lagoon deriving from currents in the mouth can be estimated as 7.0 × 103 kg for neap tides and 20.0 × 103 kg for spring tides, and the maximum phosphate contribution was estimated at 2.5 × 103 kg and 8.5 × 103 kg, respectively. Taking into account that fluvial contribution in the lagoon is practically absent, unexpanded mangroves are distributed mainly at its northern part, and organic sediment decomposition is potentially evaluated as low, we can thus conclude that the coupled effect of upwelling and tidal currents play an important role in fertilising the BM. Naturally, this mechanism works only in periods of upwelling activity, namely, from March to June, and to a lesser extent from September to October.

Preliminary measurements of plasma fluctuations in an 8-cm mercury ion thruster

NASA Technical Reports Server (NTRS)

Serafini, J. S.; Nakanishi, S.

1975-01-01

The rms magnitude, spectra, and cross correlations for the fluctuations in the beam current, the neutralizer keeper current, and the discharge current and voltage were measured for an 8-cm diameter, dished grid ion thruster for a beam current of 72 milliamps. The ratio of the rms magnitude of the fluctuations to the time-mean neutralizer keeper current was found to depend significantly on the neutralizer time-mean keeper current, the flow rate, and keeper hold diameter. The maxima of the spectra of the beam current fluctuations did not depend on the discharge fluctuations. It was found that: (1) the discharge current fluctuations do not directly contribute to the beam current fluctuations; and (2) the neutralizer contributions to the beam fluctuations are small (for good neutralizer-to-beam coupling) but not negligible and appear mostly in the higher frequency range measured.

Graduates' Transition from Study to Employment of Radiologic Technology Graduates of the Lyceum University of the Philippines--Batangas

ERIC Educational Resources Information Center

Valdez, Anacleta P.

2012-01-01

A ten-year tracer study of Radiologic Technology graduates of Lyceum of the Philippines University SY 1997-2007 using a survey-structured questionnaire was conducted to examine retrospective contribution of their education to their current work. The objectives of the study included the determination of graduates' job-placement profile; how…

A Daily Dose of CALM: Supporting Middle School Educators' Wellbeing and Classroom Functioning through a Brief Stress Reduction Intervention

ERIC Educational Resources Information Center

Harris, Alexis R.; Jennings, Patricia A.; Abenavoli, Rachel M.; Katz, Deirdre A.; Greenberg, Mark T.; Schussler, Deborah

2014-01-01

The current study involved the development, implementation, and evaluation of a universal school-based intervention designed to promote health and wellbeing among educators. This study aims to further investigate the efficacy of contemplative practices as a support for teacher wellbeing. The study contributes a new perspective to the current…

The Combination Design of Enabling Technologies in Group Learning: New Study Support Service for Visually Impaired University Students

ERIC Educational Resources Information Center

Tangsri, Chatcai; Na-Takuatoong, Onjaree; Sophatsathit, Peraphon

2013-01-01

This article aims to show how the process of new service technology-based development improves the current study support service for visually impaired university students. Numerous studies have contributed to improving assisted aid technology such as screen readers, the development and the use of audiobooks, and technology that supports individual…

Spin-dependent heat and thermoelectric currents in a Rashba ring coupled to a photon cavity

NASA Astrophysics Data System (ADS)

Abdullah, Nzar Rauf; Tang, Chi-Shung; Manolescu, Andrei; Gudmundsson, Vidar

2018-01-01

Spin-dependent heat and thermoelectric currents in a quantum ring with Rashba spin-orbit interaction placed in a photon cavity are theoretically calculated. The quantum ring is coupled to two external leads with different temperatures. In a resonant regime, with the ring structure in resonance with the photon field, the heat and the thermoelectric currents can be controlled by the Rashba spin-orbit interaction. The heat current is suppressed in the presence of the photon field due to contribution of the two-electron and photon replica states to the transport while the thermoelectric current is not sensitive to changes in parameters of the photon field. Our study opens a possibility to use the proposed interferometric device as a tunable heat current generator in the cavity photon field.

The impact of resource loss on Holocaust survivors facing war and terrorism in Israel

PubMed Central

Dekel, R.; Hobfoll, S. E.

2009-01-01

We examined the distress level of 102 Holocaust survivors in Israel during a recent period of continuous exposure of the Israeli population to terror and the threat of missile attack. Based on the Conservation of Resources (COR) theory, we explored the contribution of losses suffered during the Holocaust and of current loss of resources due to terror attacks on their distress level. Twenty one percent of the sample had probable PTSD and high psychological distress levels in general. Current loss of psychosocial resources contributed significantly to survivors’ current PTSD symptomatology and general psychological distress, above the contribution of the previous Holocaust-related loss. Our findings support COR theory, which states that traumatic events are associated with ongoing and often rapid loss of resources. Resource loss, in turn, is associated with higher distress levels. Moreover, current loss of resources compounds the impact of earlier resource losses incurred during the Holocaust. PMID:17453549

Spectroscopic study of transparency current in mid-infrared quantum cascade lasers.

PubMed

Revin, Dmitry G; Hassan, Randa S; Krysa, Andrey B; Wang, Yongrui; Belyanin, Alexey; Kennedy, Kenneth; Atkins, Chris N; Cockburn, John W

2012-08-13

We report measurements which give direct insight into the origins of the transparency current for λ ~5 µm In0.6Ga0.4As/In0.42Al0.58As quantum cascade lasers in the temperature range of 80-280 K. The transparency current values have been found from broadband transmission measurements through the laser waveguides under sub-threshold operating conditions. Two active region designs were compared. The active region of the first laser is based on double-LO-phonon relaxation approach, while the second device has only one lower level, without specially designed resonant LO-phonon assisted depopulation. It is shown that transparency current contributes more than 70% to the magnitude of threshold current at high temperatures for both designs.

Depth of origin of ocean-circulation-induced magnetic signals

NASA Astrophysics Data System (ADS)

Irrgang, Christopher; Saynisch-Wagner, Jan; Thomas, Maik

2018-01-01

As the world ocean moves through the ambient geomagnetic core field, electric currents are generated in the entire ocean basin. These oceanic electric currents induce weak magnetic signals that are principally observable outside of the ocean and allow inferences about large-scale oceanic transports of water, heat, and salinity. The ocean-induced magnetic field is an integral quantity and, to first order, it is proportional to depth-integrated and conductivity-weighted ocean currents. However, the specific contribution of oceanic transports at different depths to the motional induction process remains unclear and is examined in this study. We show that large-scale motional induction due to the general ocean circulation is dominantly generated by ocean currents in the upper 2000 m of the ocean basin. In particular, our findings allow relating regional patterns of the oceanic magnetic field to corresponding oceanic transports at different depths. Ocean currents below 3000 m, in contrast, only contribute a small fraction to the ocean-induced magnetic signal strength with values up to 0.2 nT at sea surface and less than 0.1 nT at the Swarm satellite altitude. Thereby, potential satellite observations of ocean-circulation-induced magnetic signals are found to be likely insensitive to deep ocean currents. Furthermore, it is shown that annual temporal variations of the ocean-induced magnetic field in the region of the Antarctic Circumpolar Current contain information about sub-surface ocean currents below 1000 m with intra-annual periods. Specifically, ocean currents with sub-monthly periods dominate the annual temporal variability of the ocean-induced magnetic field.

The Current Status of Peer Assessment Techniques and Sociometric Methods

ERIC Educational Resources Information Center

Bukowski, William M.; Castellanos, Melisa; Persram, Ryan J.

2017-01-01

Current issues in the use of peer assessment techniques and sociometric methods are discussed. Attention is paid to the contributions of the four articles in this volume. Together these contributions point to the continual level of change and progress in these techniques. They also show that the paradigm underlying these methods has been unchanged…

Electronic Properties of Grain Boundaries in GaAs: A Study of Oriented Bicrystals Prepared by Epitaxial Lateral Overgrowth.

DTIC Science & Technology

1984-05-10

overgrowth from a spoke 90 pattern of radial stripe openings at 1 intervals on an Si0 2 coated (110) surface. Bright regions are GaAs and dark regions are Si0...the dark current for such an ideal device is given by Idark - Io[exp(eVbi/AokT) - 1] , (11-l) where Io is a proportionality constant describing the...recombination and leakage currents which contribute to an increased dark current. The value of Voc is determined by the built-in junction barrier height and the

Challenges of Zinc-Specific Transrectal Fluorescence Tomography to Detect Prostate Cancer

DTIC Science & Technology

2012-10-01

wavelength, aem  and sem as those at emission wavelength, afl as the absorption coefficient of the fluorophore at the excitation wavelength,  as the...tentatively accepted” by Medical Physics at the time of this annual report being submitted. The current pre-doctoral trainee PI is Mr. Anqi Zhang. The...year 2 report thus contains progresses contributed by both the former and current trainee PIs. During the year 2 of this study, we have furthered

Professional expertise amongst speech-language therapists: "willing to share".

PubMed

Jackson, Bianca N; Purdy, Suzanne Carolyn; Cooper-Thomas, Helena

2017-09-18

Purpose The current healthcare environment provides several challenges to the existing roles of healthcare professionals. The value of the professional expert is also under scrutiny. The purpose of this paper is to generate a construction of professional expertise amongst practitioners in the current healthcare environment. It used the speech-language therapy community in New Zealand (NZ) as an example. Design/methodology/approach Speech-language therapists currently practicing in NZ completed an online survey including qualitative and quantitative components. The range of experience and work settings of participants ( n=119) was representative of the workforce. Findings Participants clearly identified being "highly experienced" and "having in-depth knowledge" as essential elements of professional expertise. Thematic analysis generated two interconnected themes of a professional expert being a personal leader and teacher, and a highly experienced, knowledgeable and skilful practitioner. Additionally, practitioners needed to be seen to contribute to the community in order to be known as experts. Clinical practice was valued differently from research generation. Originality/value This study is novel in exploring a construction of professional expertise amongst practitioners in a current healthcare community. Within that community, experts could be viewed as highly effective practitioners that visibly contribute to the professional community. The study draws attention to the role of reputation and the impacts of being a clinical teacher or leader compared with pursuing a research role. This could be particularly relevant in the promotion of evidence-based practice.

A Review of Our Roots: Blacks in Gerontology

PubMed Central

Brown, Candace S.; Baker, Tamara A.; Mingo, Chivon A.; Harden, J. Taylor; Whitfield, Keith; Aiken-Morgan, Adrienne T.; Phillips, Karon L.; Washington, Tiffany

2014-01-01

The historical underpinnings in the field of gerontology rest on the contributions of scholars across a myriad of racial and ethnic backgrounds. With the increasing diversity of the adult population, there is a need to increase the number of researchers who study older adults from diverse racial and ethnic populations in general and Black elderly people in particular. Furthermore, it is important to document the participation of Black older adults in our earliest and continuing research efforts. Understanding the historical context and the foundational influence of Black scholars in this field is critical. To realize its humble beginnings, one must become aware of the contributions by Black scholars who have a vested interest in the aging process. With universal similarities and unique differences among older adults, there is a need to acknowledge the past and current scholarship of those who study the aging processes of Blacks while marveling over the future possibilities. The purpose of this review is to elucidate the legacy and current contributions, philosophies, and research of Black scholars in the field of gerontology. In addition, exploration of the theoretical and conceptual frameworks used to establish national and organizational initiatives is reviewed. The impetus in initiating and continuing this work requires a “knowledge of our roots” while moving into the future. It is important to learn the history and significance of Black scholars in gerontology, the contributions of older Blacks, and appreciate the resiliency and marveled life course of this unique population. PMID:24022695

Estimate of the hadronic vacuum polarization disconnected contribution to the anomalous magnetic moment of the muon from lattice QCD

NASA Astrophysics Data System (ADS)

Chakraborty, Bipasha; Davies, C. T. H.; Koponen, J.; Lepage, G. P.; Peardon, M. J.; Ryan, S. M.

2016-04-01

The quark-line disconnected diagram is a potentially important ingredient in lattice QCD calculations of the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon. It is also a notoriously difficult one to evaluate. Here, for the first time, we give an estimate of this contribution based on lattice QCD results that have a statistically significant signal, albeit at one value of the lattice spacing and an unphysically heavy value of the u /d quark mass. We use HPQCD's method of determining the anomalous magnetic moment by reconstructing the Adler function from time moments of the current-current correlator at zero spatial momentum. Our results lead to a total (including u , d and s quarks) quark-line disconnected contribution to aμ of -0.15 % of the u /d hadronic vacuum polarization contribution with an uncertainty which is 1% of that contribution.

Social Approach and Emotion Recognition in Fragile X Syndrome

ERIC Educational Resources Information Center

Williams, Tracey A.; Porter, Melanie A.; Langdon, Robyn

2014-01-01

Evidence is emerging that individuals with Fragile X syndrome (FXS) display emotion recognition deficits, which may contribute to their significant social difficulties. The current study investigated the emotion recognition abilities, and social approachability judgments, of FXS individuals when processing emotional stimuli. Relative to…

Young Unlicensed Drivers: Three Studies to Understand the Association of Lifestyle and Area Associated Risk

DOT National Transportation Integrated Search

2010-09-01

Background: A significant proportion of teens killed in motor vehicle crashes die in crashes involving a never-licensed driver (NLD); however, little is currently known about NLDs aside from their crash involvement. Given their contribution to young ...

Technological Advances in the Study of Reading: An Introduction.

ERIC Educational Resources Information Center

Henk, William A.

1991-01-01

Describes the purpose and functional operation of new computer-driven technologies such as computerized axial tomography, positron emissions transaxial tomography, regional cerebral blood flow monitoring, magnetic resonance imaging, and brain electrical activity mapping. Outlines their current contribution to the knowledge base. Speculates on the…

The Human Side of Information's Converging Technology.

ERIC Educational Resources Information Center

Williams, Berney

1982-01-01

Discusses current issues in the design of information systems, noting contributions from three professions--computer science, human factors engineering, and information science. The eclectic nature of human factors engineering and the difficulty of drawing together studies with human engineering or software psychological components from diverse…

Sound management may sequester methane in grazed rangeland ecosystems

USDA-ARS?s Scientific Manuscript database

Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implement...

A poloidal section neutron camera for MAST upgrade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sangaroon, S.; Weiszflog, M.; Cecconello, M.

2014-08-21

The Mega Ampere Spherical Tokamak Upgrade (MAST Upgrade) is intended as a demonstration of the physics viability of the Spherical Tokamak (ST) concept and as a platform for contributing to ITER/DEMO physics. Concerning physics exploitation, MAST Upgrade plasma scenarios can contribute to the ITER Tokamak physics particularly in the field of fast particle behavior and current drive studies. At present, MAST is equipped with a prototype neutron camera (NC). On the basis of the experience and results from previous experimental campaigns using the NC, the conceptual design of a neutron camera upgrade (NC Upgrade) is being developed. As part ofmore » the MAST Upgrade, the NC Upgrade is considered a high priority diagnostic since it would allow studies in the field of fast ions and current drive with good temporal and spatial resolution. In this paper, we explore an optional design with the camera array viewing the poloidal section of the plasma from different directions.« less

Electrical valley filtering in transition metal dichalcogenides

NASA Astrophysics Data System (ADS)

Hsieh, Tzu-Chi; Chou, Mei-Yin; Wu, Yu-Shu

2018-03-01

This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and perform the study with both a k .p -based analytic method and a recursive Green's function-based numerical method. The study yields the transmission coefficient as a function of incident energy and transverse wave vector, for holes going through lateral quantum barriers oriented in either armchair or zigzag directions, in both homogeneous and heterogeneous systems. The main findings are the following: (1) The tunneling current valley polarization increases with increasing barrier width or height; (2) both the valley-orbit interaction and band structure warping contribute to valley-dependent tunneling, with the former contribution being manifest in structures with asymmetric potential barriers, and the latter being orientation dependent and reaching maximum for transmission in the armchair direction; and (3) for transmission ˜0.1 , a tunneling current valley polarization of the order of 10 % can be achieved.

[Urban sporotrichosis: a neglected epidemic in Rio de Janeiro, Brazil].

PubMed

Silva, Margarete Bernardo Tavares da; Costa, Mônica Motta de Mattos; Torres, Carla Carrilho da Silva; Galhardo, Maria Clara Gutierrez; Valle, Antonio Carlos Francesconi do; Magalhães, Mônica de Avelar F M; Sabroza, Paulo Chagastelles; Oliveira, Rosely Magalhães de

2012-10-01

In the scientific literature, sporotrichosis has traditionally been associated with agricultural work, since the causative agent is found naturally in the soil. However, cases have been reported recently in an urban area, related to zoonotic transmission. The current study aimed to contribute to knowledge on sporotrichosis in an urban area through an exploratory analysis of its socio-spatial distribution in Rio de Janeiro, Brazil, from 1997 to 2007, identifying the areas with the heaviest transmission. The database from the Health Surveillance Service at the Evandro Chagas Institute for Clinical Research, Oswaldo Cruz Foundation, was used to estimate incidence rates and spatial distribution. During the study period, 1,848 cases of sporotrichosis were reported, predominantly in adult women not currently in the labor market. The leading source of infection was wounds caused by domestic cats, which contributed to the spread of sporotrichosis in this urban area. Georeferencing of 1,681 cases showed a transmission belt along the border between the city of Rio de Janeiro and the adjacent municipalities in the Greater Metropolitan Area.

Misbehaving macrophages in the pathogenesis of psoriasis.

PubMed

Clark, Rachael A; Kupper, Thomas S

2006-08-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin--or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell-mediated pathways of inflammation.

Working Memory Deficits in Boys with Attention-Deficit/Hyperactivity Disorder (ADHD): The Contribution of Central Executive and Subsystem Processes

ERIC Educational Resources Information Center

Rapport, Mark D.; Alderson, R. Matt; Kofler, Michael J.; Sarver, Dustin E.; Bolden, Jennifer; Sims, Valerie

2008-01-01

The current study investigated contradictory findings from recent experimental and meta-analytic studies concerning working memory deficits in ADHD. Working memory refers to the cognitive ability to temporarily store and mentally manipulate limited amounts of information for use in guiding behavior. Phonological (verbal) and visuospatial…

Conscientiousness and Public Health: Synthesizing Current Research to Promote Healthy Aging

ERIC Educational Resources Information Center

Reiss, David; Eccles, Jacquelynne S.; Nielsen, Lisbeth

2014-01-01

In this special section, 9 studies and 6 commentaries make a unique contribution to the study of personality. They focus on the five-factor model and, in particular, one of those 5: conscientiousness. This trait has had astonishing success in the actuarial prediction of adaptive outcomes in adulthood and aging, but we have little understanding of…

Natural Disaster: Long-Range Impact on Human Response to Future Disaster Threats.

ERIC Educational Resources Information Center

Hanson, Susan; And Others

1979-01-01

The study examines the effect of a prior tornado disaster occurring in a community and that community's current response to a tornado threat. The study concludes that it is not past experience with tornadoes that relates to response to warnings, but rather awareness. Experience is but one source of information contributing to their awareness. (RE)

Parenting, Community, and Religious Predictors of Positive and Negative Developmental Outcomes among Muslim Adolescents

ERIC Educational Resources Information Center

Krauss, Steven Eric; Hamzah, Azimi; Ismail, Ismi Arif; Suandi, Turiman; Hamzah, Siti Raba'ah; Dahalan, Dzuhailmi; Idris, Fazilah

2014-01-01

Despite existing research on the contribution of social context and religiosity to adolescent behavioral outcomes, few studies have attempted to explore this topic among Muslim adolescents in non-Western settings, looking at both positive and negative outcomes. In response to this gap, the current study explored the effects of three dimensions of…

Motivating Factors for Teaching and Studying Music at Two-Year Colleges: A Survey of Faculty and Students

ERIC Educational Resources Information Center

Stewart, John R.; Williams, Yolanda Y.; Vu, Kinh T.; Collins, Tracey R.; Clementson, Casey J.; Berberick, David M.

2015-01-01

The purpose of this study was to explore what motivates faculty and student involvement in this educational environment and how student participation in music coursework contributes to current musical endeavors. The research team utilized a modified explanatory sequential mixed methods design to collect survey data and focus group data from…

Generation 1.5 Written Error Patterns: A Comparative Study

ERIC Educational Resources Information Center

Doolan, Stephen M.; Miller, Donald

2012-01-01

In an attempt to contribute to existing research on Generation 1.5 students, the current study uses quantitative and qualitative methods to compare error patterns in a corpus of Generation 1.5, L1, and L2 community college student writing. This error analysis provides one important way to determine if error patterns in Generation 1.5 student…

Practical and Scholarly Implications of Information Behaviour Research: A Pilot Study of Research Literature

ERIC Educational Resources Information Center

Koh, Kyungwon; Rubenstein, Ellen; White, Kelvin

2015-01-01

Introduction: This pilot study examined how current information behaviour research addresses the implications and potential impacts of its findings. The goal was to understand what implications and contributions the field has made and how effectively authors communicate implications of their findings. Methods: We conducted a content analysis of 30…

Beyond Breadth: The Contributions of Vocabulary Depth to Reading Comprehension among Skilled Readers

ERIC Educational Resources Information Center

Binder, Katherine S.; Cote, Nicole Gilbert; Lee, Cheryl; Bessette, Emily; Vu, Huong

2017-01-01

This study investigated the relationships among vocabulary breadth, vocabulary depth, reading comprehension, and reading rate among college-aged students. While the relationships of some of these variables have been explored in previous research, the current study's focus on the role of vocabulary depth on the literacy measures within a sample of…

Postgraduate Preferences: A Study of Factors Contributing to Programme Satisfaction amongst Masters Students

ERIC Educational Resources Information Center

Frumkin, Lara A.; Milankovic-Atkinson, Maya; Sadler, Chris

2007-01-01

Background: Universities have a vested interest in attracting and encouraging enrolment of as many high calibre students as possible. With greater frequency, universities are using marketing techniques to do so. Aims: The study reviewed current student opinions of a programme within a UK university to discover its shortcomings and strengths.…

Using Concept-Based Instruction in the L2 Classroom: Perspectives from Current and Future Language Teachers

ERIC Educational Resources Information Center

Williams, Lawrence; Abraham, Lee B.; Negueruela-Azarola, Eduardo

2013-01-01

A number of recent studies (see, for example, Lantolf, 2010; Negueruela & Lantolf, 2006; van Compernolle, 2011) have focused on the use of learning tools developed according to the principles of concept-based instruction (CBI). Using videorecorded data from interviews and observations of classroom instruction, our study seeks to contribute to…

The Relationship between Iranian EFL Teachers' Collective Efficacy Beliefs, Teaching Experience and Perception of Teacher Empowerment

ERIC Educational Resources Information Center

Baleghizadeh, Sasan; Goldouz, Elnaz

2016-01-01

The present study aimed to contribute to the current findings of the relationship between collective efficacy perceptions of EFL teachers and their perception of teacher empowerment. To this end, 147 Iranian EFL teachers from a well-known institute in Tehran participated in the study. The instruments used were two questionnaires: Collective…

The Effect of Classroom Web Applications on Teaching, Learning and Academic Performance among College of Education Female Students

ERIC Educational Resources Information Center

Aljraiwi, Seham Salman

2017-01-01

The current study proposes web applications-based learning environment to promote teaching and learning activities in the classrooms. It also helps teachers facilitate learners' contributions in the process of learning and improving their motivation and performance. The case study illustrated that female students were more interested in learning…

You and the Civil Air Patrol.

DTIC Science & Technology

1988-04-01

currently holds the rank of Major In CAP. He was the Director of Senior Programs for the National Capital Wing for three years. In this capacity, he...2 Assumptions and Limitations ............................ 2 Previous Studies...................................... 2 CHAPTER TWO... limited thereby contributing to the problem. ASSUMPTIONS AND LIMITATIONS The time limitation and limited scope of this study prevented surveying all the

Relationships of Mathematics Anxiety, Mathematics Self-Efficacy and Mathematics Performance of Adult Basic Education Students

ERIC Educational Resources Information Center

Watts, Beverly Kinsey

2011-01-01

Competent mathematical skills are needed in the workplace as well as in the college setting. Adults in Adult Basic Education classes and programs generally perform below high school level competency, but very few studies have been performed investigating the predictors of mathematical success for adults. The current study contributes to the…

Exploring the Persistence of Adult Women at a Midwest Community College

ERIC Educational Resources Information Center

Cox, Elizabeth M.; Ebbers, Larry H.

2010-01-01

The purpose of this study was to describe, interpret, and analyze the educational experiences and factors contributing to the decision to persist for adult, female, part-time students currently enrolled at a community college in the Midwest. This study sought to expand the research on student retention by describing the perspectives of adult…

Peer Victimisation and Its Relation to Class Relational Climate and Class Moral Disengagement among School Children

ERIC Educational Resources Information Center

Thornberg, Robert; Wänström, Linda; Pozzoli, Tiziana

2017-01-01

The aim of the present study was to examine whether class climate and class moral disengagement each contribute to explain different levels of victimisation among classes. Eight-hundred-and-ninety-nine children from 43 Swedish elementary school classes participated in the current study. Class moral disengagement, class relational climate and peer…

On the Contribution of Curl-Free Current Patterns to the Ultimate Intrinsic Signal-to-Noise Ratio at Ultra-High Field Strength.

PubMed

Pfrommer, Andreas; Henning, Anke

2017-05-01

The ultimate intrinsic signal-to-noise ratio (SNR) is a coil independent performance measure to compare different receive coil designs. To evaluate this benchmark in a sample, a complete electromagnetic basis set is required. The basis set can be obtained by curl-free and divergence-free surface current distributions, which excite linearly independent solutions to Maxwell's equations. In this work, we quantitatively investigate the contribution of curl-free current patterns to the ultimate intrinsic SNR in a spherical head-sized model at 9.4 T. Therefore, we compare the ultimate intrinsic SNR obtained with having only curl-free or divergence-free current patterns, with the ultimate intrinsic SNR obtained from a combination of curl-free and divergence-free current patterns. The influence of parallel imaging is studied for various acceleration factors. Moreover results for different field strengths (1.5 T up to 11.7 T) are presented at specific voxel positions and acceleration factors. The full-wave electromagnetic problem is analytically solved using dyadic Green's functions. We show, that at ultra-high field strength (B 0 ⩾7T) a combination of curl-free and divergence-free current patterns is required to achieve the best possible SNR at any position in a spherical head-sized model. On 1.5- and 3T platforms, divergence-free current patterns are sufficient to cover more than 90% of the ultimate intrinsic SNR. Copyright © 2017 John Wiley & Sons, Ltd.

What have humans done for evolutionary biology? Contributions from genes to populations.

PubMed

Briga, Michael; Griffin, Robert M; Berger, Vérane; Pettay, Jenni E; Lummaa, Virpi

2017-11-15

Many fundamental concepts in evolutionary biology were discovered using non-human study systems. Humans are poorly suited to key study designs used to advance this field, and are subject to cultural, technological, and medical influences often considered to restrict the pertinence of human studies to other species and general contexts. Whether studies using current and recent human populations provide insights that have broader biological relevance in evolutionary biology is, therefore, frequently questioned. We first surveyed researchers in evolutionary biology and related fields on their opinions regarding whether studies on contemporary humans can advance evolutionary biology. Almost all 442 participants agreed that humans still evolve, but fewer agreed that this occurs through natural selection. Most agreed that human studies made valuable contributions to evolutionary biology, although those less exposed to human studies expressed more negative views. With a series of examples, we discuss strengths and limitations of evolutionary studies on contemporary humans. These show that human studies provide fundamental insights into evolutionary processes, improve understanding of the biology of many other species, and will make valuable contributions to evolutionary biology in the future. © 2017 The Author(s).

What have humans done for evolutionary biology? Contributions from genes to populations

PubMed Central

Briga, Michael; Griffin, Robert M.; Berger, Vérane; Pettay, Jenni E.

2017-01-01

Many fundamental concepts in evolutionary biology were discovered using non-human study systems. Humans are poorly suited to key study designs used to advance this field, and are subject to cultural, technological, and medical influences often considered to restrict the pertinence of human studies to other species and general contexts. Whether studies using current and recent human populations provide insights that have broader biological relevance in evolutionary biology is, therefore, frequently questioned. We first surveyed researchers in evolutionary biology and related fields on their opinions regarding whether studies on contemporary humans can advance evolutionary biology. Almost all 442 participants agreed that humans still evolve, but fewer agreed that this occurs through natural selection. Most agreed that human studies made valuable contributions to evolutionary biology, although those less exposed to human studies expressed more negative views. With a series of examples, we discuss strengths and limitations of evolutionary studies on contemporary humans. These show that human studies provide fundamental insights into evolutionary processes, improve understanding of the biology of many other species, and will make valuable contributions to evolutionary biology in the future. PMID:29118130

The influence of wave-, wind- and tide-forced currents on headland sand bypassing - Study case: Santa Catarina Island north shore, Brazil

NASA Astrophysics Data System (ADS)

Vieira da Silva, Guilherme; Toldo, Elírio E., Jr.; Klein, Antonio H. da F.; Short, Andrew D.

2018-07-01

Investigations of headland sand bypassing are still an under-reported subject in the literature. This paper aims to understand the contribution of currents forced by different mechanisms such as tides, winds (i.e. local wind acting over the ocean surface generating currents, without considering wave generation) and waves (as they approach/break on the coast) to headland sand bypassing. The study was carried out in an area comprising a series of seven headlands with varying wave exposure due to changes in shoreline orientation and increasing tidal influence close to a relatively large bay. This paper uses a calibrated and validated process-based model (Delft3D) to simulate a series of scenarios including spring and neap tides during flood and ebb conditions and a range of wind and wave scenarios that encompass both average and extreme conditions. The results indicate that waves are the main driving force for the headland bypassing as they transport sand at rates two orders of magnitude higher than tide- or wind-driven sediment transport. The tide-driven currents can only transport sediment during spring tides in locations where the currents are intensified. It is also demonstrated that the wave direction plays an important role in sediment transport. In exposed areas with larger headlands a combination of wave directions is required to first transport sediment offshore (out of the beach) and secondly to transport sediment alongshore and back to the next beach. Whereas in areas with little variation in wave direction exposure, the same oblique wave direction is responsible for the entire headland bypassing process. This is the first time the contribution of tide-, winds- and wave-generated sediment transport to headland bypassing have been studied.

Current density tensors

NASA Astrophysics Data System (ADS)

Lazzeretti, Paolo

2018-04-01

It is shown that nonsymmetric second-rank current density tensors, related to the current densities induced by magnetic fields and nuclear magnetic dipole moments, are fundamental properties of a molecule. Together with magnetizability, nuclear magnetic shielding, and nuclear spin-spin coupling, they completely characterize its response to magnetic perturbations. Gauge invariance, resolution into isotropic, deviatoric, and antisymmetric parts, and contributions of current density tensors to magnetic properties are discussed. The components of the second-rank tensor properties are rationalized via relationships explicitly connecting them to the direction of the induced current density vectors and to the components of the current density tensors. The contribution of the deviatoric part to the average value of magnetizability, nuclear shielding, and nuclear spin-spin coupling, uniquely determined by the antisymmetric part of current density tensors, vanishes identically. The physical meaning of isotropic and anisotropic invariants of current density tensors has been investigated, and the connection between anisotropy magnitude and electron delocalization has been discussed.

The Contribution of Expanding Portion Sizes to the US Obesity Epidemic

PubMed Central

Young, Lisa R.; Nestle, Marion

2002-01-01

Objectives. Because larger food portions could be contributing to the increasing prevalence of overweight and obesity, this study was designed to weigh samples of marketplace foods, identify historical changes in the sizes of those foods, and compare current portions with federal standards. Methods. We obtained information about current portions from manufacturers or from direct weighing; we obtained information about past portions from manufacturers or contemporary publications. Results. Marketplace food portions have increased in size and now exceed federal standards. Portion sizes began to grow in the 1970s, rose sharply in the 1980s, and have continued in parallel with increasing body weights. Conclusions. Because energy content increases with portion size, educational and other public health efforts to address obesity should focus on the need for people to consume smaller portions. PMID:11818300

Time-dependent characteristics of the dielectric barrier discharge in Xe-Cl2 mixture and kinetics of the XeCl∗ molecules

NASA Astrophysics Data System (ADS)

Avtaeva, Svetlana

2014-04-01

Time-dependent characteristics of the dielectric barrier discharge in Xe-Cl2 mixture at chlorine concentration of 0.5% and kinetic processes governing the generation of XeCl∗ molecules are studied using the 1D fluid model. It is shown that at low voltage amplitude (5 kV) a one-peak mode of the discharge is observed and at high voltage amplitude (7 kV) a two-peak mode of the discharge appears. The radiation power of the XeCl∗ band increases with amplitude of the supply voltage. It is demonstrated that the harpoon reaction Xe∗ + Cl2 → XeCl∗ + Cl provides the greatest contribution into generation of XeCl∗ exciplex molecules during short current pulses and the ion-ion recombination Xe+ 2 + Cl- → XeCl* + Xe provides the greatest contribution during afterglow. Quenching of XeCl∗ molecules is a result of the radiative decay XeCl∗ → Xe + Cl + hv (308 nm). During current spike the great contribution into quenching of XeCl∗ provides also the dissociative ionization e + XeCl∗ → Xe+ + Cl + 2e.

SIMBIOS Project; 2003 Annual Report

NASA Technical Reports Server (NTRS)

McClain, Charles R.; Fargion, Giulietta S.

2003-01-01

The purpose of this technical report is to provide current documentation of the the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, NASA Research Announcement (NRA) research status, satellite data processing, data product validation, and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project. The SIMBIOS Science Team Principal Investigators (PIs) original contributions to this report are in chapters four and above. The purpose of these contributions is to describe the current research status of the SIMBIOS-NRA-99 funded research. The contributions are published as submitted, with the exception of minor edits to correct obvious grammatical or clerical errors.

Salty sisters: The women of halophiles

PubMed Central

Baxter, Bonnie K.; Gunde-Cimerman, Nina; Oren, Aharon

2014-01-01

A history of halophile research reveals the commitment of scientists to uncovering the secrets of the limits of life, in particular life in high salt concentration and under extreme osmotic pressure. During the last 40 years, halophile scientists have indeed made important contributions to extremophile research, and prior international halophiles congresses have documented both the historical and the current work. During this period of salty discoveries, female scientists, in general, have grown in number worldwide. But those who worked in the field when there were small numbers of women sometimes saw their important contributions overshadowed by their male counterparts. Recent studies suggest that modern female scientists experience gender bias in matters such as conference invitations and even representation among full professors. In the field of halophilic microbiology, what is the impact of gender bias? How has the participation of women changed over time? What do women uniquely contribute to this field? What are factors that impact current female scientists to a greater degree? This essay emphasizes the “her story” (not “history”) of halophile discovery. PMID:24926287

High-field magnetoconductance in Anderson insulators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaknin, A.; Frydman, A.; Ovadyahu, Z.

1996-11-01

We report on high-field magnetoconductance measurements made on indium-oxide films as a function of temperature and static disorder. Special emphasis is given to the strong-localization regime where the magnetoconductance reveals a negative contribution associated with a spin-alignment mechanism in addition to the positive contribution associated with orbital, quantum-coherence effects. While the overall features of the theoretically expected effects are observed in our experiments, they depart in certain ways from the detailed predictions. We discuss the merits and shortcomings of current models to describe them, in particular, as they apply to the regime where the localized wave functions become larger thanmore » the Bohr radius. The main results of this paper are both quantum interference and spin effects contribute to the magnetoconductance throughout the entire range studied. In the limit of very strong disorder, the quantum interference effects are faithfully described by the Nguyen {ital et} {ital al}. model. The spin effects, on the other hand, show only qualitative agreement with current models which are unable to account for the saturation field being insensitive to changes in disorder. {copyright} {ital 1996 The American Physical Society.}« less

Contributions of fluid convection and electrical migration to transport in cartilage: relevance to loading.

PubMed

Garcia, A M; Frank, E H; Grimshaw, P E; Grodzinsky, A J

1996-09-15

We have studied the contributions of diffusion, fluid flow and electrical migration to molecular transport through adult articular cartilage explants using neutral and charged solutes that were either radiolabeled (3H2O, [35S]sulfate, [3H]thymidine, [3H]raffinose, and a synthetic matrix metalloproteinase inhibitor) or fluorescently tagged (NSPA and Lissamine-dextran). In order to induce fluid flow within the cartilage matrix without mechanical deformation, electric current densities were applied across cartilage disks. These currents produced electroosmotic fluid velocities of 1-2 microns/s, magnitudes that have been reported to exist during joint loading in vivo. This fluid convection enhanced neutral solute flux relative to passive diffusion alone by a factor that increased with the size of the solute. While the enhancement factor for 3H2O was 2.3-fold, that for [3H]raffinose (594 Da) and similar sized neutral solutes was 10-fold, suggesting that the effect of fluid flow is important even for small solutes. The largest enhancement (25-fold) was seen for the neutral 10-kDa Lissamine-dextran, confirming that fluid convection is most important for large solutes. We also studied the electrophoretic contribution to solute flux, which is relevant to the presence of intratissue streaming potentials induced during loading in vivo. Using the negatively charged [35S]sulfate ion with a range of current densities, as much as a 10-fold enhancement in flux was observed. Values for the intrinsic transport properties of the solutes (e.g., diffusivity, electrical mobility, hydrodynamic hindrance factor) can be obtained from the data.

North-South Asymmetric Solar Cycle Evolution: Signatures in the Photosphere and Consequences in the Corona

NASA Astrophysics Data System (ADS)

Virtanen, I. I.; Mursula, K.

2014-02-01

The heliospheric current sheet is the continuum of the coronal magnetic equator that divides the heliospheric magnetic field into two sectors (polarities). Several recent studies have shown that the heliospheric current sheet is southward shifted during approximately 3 years in the solar declining phase (the so-called bashful ballerina phenomenon). In this article we study the hemispherical asymmetry in the photospheric and coronal magnetic fields using Wilcox Solar Observatory measurements of the photospheric magnetic field since 1976 as well as the potential field source surface model. Multipole analysis of the photospheric magnetic field shows that during the late declining phase of solar cycles since the 1970s, the "bashful ballerina phenomenon" is a consequence of the g^{0}_{2} quadrupole term, signed oppositely to the dipole moment. Surges of new flux transport magnetic field from low latitudes to the poles, thus leading to a systematically varying contribution to the g^{0}_{2}-term from different latitudes. In the case of a north-south asymmetric flux production, this is seen as a quadrupole contribution traveling toward higher latitudes. When the quadrupole term is largest, the main contribution comes from the polar latitudes. At least during the four recent solar cycles, the g^{0}_{2}-term arises because the magnitude of the southern polar field is larger than the magnitude found in the north in the declining phase of the cycle. In the heliosphere this hemispheric asymmetry of the coronal fields is seen as a southward shift of the heliospheric current sheet by about 2°.

DE 1 observations of type 1 counterstreaming electrons and field-aligned currents

NASA Technical Reports Server (NTRS)

Lin, C. S.; Burch, J. L.; Barfield, J. N.; Sugiura, M.; Nielsen, E.

1984-01-01

Dynamics Explorer 1 satellite observations of plasma and magnetic fields during type one counterstreaming electron events are presented. Counterstreaming electrons are observed at high altitudes in the region of field-aligned current. The total current density computed from the plasma data in the 18-10,000 eV energy range is generally about 1-2 micro-A/sq m. For the downward current, low-energy electrons contribute more than 40 percent of the total plasma current density integrated above 18 eV. For the upward current, such electrons contribute less than 50 percent of that current density. Electron beams in the field-aligned direction are occasionally detected. The pitch angle distributions of counterstreaming electrons are generally enhanced at both small and large pitch angles. STARE simultaneous observations for one DE 1 pass indicated that the field-aligned current was closed through Pedersen currents in the ionosphere. The directions of the ionospheric current systems are consistent with the DE 1 observations at high altitudes.

Contribution of the graded region of a HgCdTe diode to its saturation current

NASA Technical Reports Server (NTRS)

Schacham, S. E.; Finkman, E.

1990-01-01

Experimental results show that the contribution of the graded region to the current of Hg(1-x)Cd(x)Te diodes is not negligible, as compared to that of the p type bulk. The theoretical analysis reveals the influence of the electric field present outside the depletion region on the current generated by the graded region. The analysis shows the importance of the lifetime profile in the graded region, which is a function of the specific recombination mechanism and its dependence on the local dopant concentration. The effect of parameters such as substrate concentration, surface concentration, and junction depth on this current is discussed.

Theoretical analysis of oscillatory terms in lattice heat-current time correlation functions and their contributions to thermal conductivity

NASA Astrophysics Data System (ADS)

Pereverzev, Andrey; Sewell, Tommy

2018-03-01

Lattice heat-current time correlation functions for insulators and semiconductors obtained using molecular dynamics (MD) simulations exhibit features of both pure exponential decay and oscillatory-exponential decay. For some materials the oscillatory terms contribute significantly to the lattice heat conductivity calculated from the correlation functions. However, the origin of the oscillatory terms is not well understood, and their contribution to the heat conductivity is accounted for by fitting them to empirical functions. Here, a translationally invariant expression for the heat current in terms of creation and annihilation operators is derived. By using this full phonon-picture definition of the heat current and applying the relaxation-time approximation we explain, at least in part, the origin of the oscillatory terms in the lattice heat-current correlation function. We discuss the relationship between the crystal Hamiltonian and the magnitude of the oscillatory terms. A solvable one-dimensional model is used to illustrate the potential importance of terms that are omitted in the commonly used phonon-picture expression for the heat current. While the derivations are fully quantum mechanical, classical-limit expressions are provided that enable direct contact with classical quantities obtainable from MD.

Foster Youth and Post-Secondary Education: A Study of the Barriers and Supports That Led to Academic Achievement

ERIC Educational Resources Information Center

Morton, Brenda M.

2012-01-01

The purpose of this qualitative research study was to explore the perceptions of former and current foster youth on the barriers, supports, helps, and strategies they encountered during their K-12 education, and to learn how these contributed to their ability to enroll in post-secondary education. The study included in-depth interviews of 11…

Emerging and established technologies to increase nitrogen use efficiency of cereals

USDA-ARS?s Scientific Manuscript database

Nitrogen (N) fertilizers are expensive inputs; additionally, loss of N increases costs, contributes to soil acidification, and causes off-site pollution of air, groundwater and waterways. This study reviews current knowledge about technologies for N fertilization with potential to increase N use eff...

The Development of Individuation in Autism

ERIC Educational Resources Information Center

O'Hearn, Kirsten; Franconeri, Steven; Wright, Catherine; Minshew, Nancy; Luna, Beatriz

2013-01-01

Evidence suggests that people with autism rely less on holistic visual information than typical adults. The current studies examine this by investigating core visual processes that contribute to holistic processing--namely, individuation and element grouping--and how they develop in participants with autism and typically developing (TD)…

Underlying Cause(s) of Letter Perseveration Errors

ERIC Educational Resources Information Center

Fischer-Baum, Simon; Rapp, Brenda

2012-01-01

Perseverations, the inappropriate intrusion of elements from a previous response into a current response, are commonly observed in individuals with acquired deficits. This study specifically investigates the contribution of failure-to activate and failure-to-inhibit deficit(s) in the generation of letter perseveration errors in acquired…

The mineral content of tap water in United States households

USDA-ARS?s Scientific Manuscript database

The composition of tap water contributes to dietary intake of minerals. The USDA’s Nutrient Data Laboratory (NDL) conducted a study of the mineral content of residential tap water, to generate current data for the USDA National Nutrient Database. Sodium, potassium, calcium, magnesium, iron, copper...

Addiction Genetics and Pleiotropic Effects of Common Haplotypes that Make Polygenic Contributions to Vulnerability to Substance Dependence

PubMed Central

Uhl, George R.; Drgon, Tomas; Johnson, Catherine; Liu, Qing-Rong

2016-01-01

Abundant evidence from family, adoption, and twin studies point to large genetic contributions to individual differences in vulnerability to develop dependence on one or more addictive substances. Twin data suggest that most of this genetic vulnerability is shared by individuals who are dependent on a variety of addictive substances. Molecular genetic studies, especially genomewide and candidate gene association studies, have elucidated common haplotypes in dozens of genes that appear to make polygenic contributions to vulnerability to developing dependence. Most genes that harbor currently identified addiction-associated haplotypes are expressed in the brain. Haplotypes in many of the same genes are identified in genomewide association studies that compare allele frequencies in substance dependent vs. control individuals from European, African, and Asian racial/ethnic backgrounds. Many of these addiction-associated haplotypes display pleiotropic influences on a variety of related brain-based phenotypes that display 1) substantial heritability and 2) clinical cooccurence with substance dependence. PMID:19152208

The Contribution of Music to the Fluent Writing Skills: Mayaz Technique

ERIC Educational Resources Information Center

Batur, Zekerya

2016-01-01

This is an experimental study. In this study, experimental and control groups have been formed based on the scores obtained from Turkish language exams. The study group consists of 80 pupils currently studying in the 5th and 6th grades of the secondary school who have an average GPA of 70 to 80 (of the 5th grade pupils, 20 of them are in the…

Media and Influence

NASA Astrophysics Data System (ADS)

Bennett, William H.

The public information media provides information on current events (news), entertainment (programming), and opinions offered by trusted public sources (e.g., business, academic or religious spokespersons, journalists, and government officials). Consequently, it is a major force in shaping a populace's attitudes toward significant social issues and of great interest to intervention planners. The chapter attempts to provide modelers and intervention analysts alike with sufficient understanding of media mechanisms and current research that they can begin contributing to, and benefiting from this important area of study.

Rationale for a GRAVSAT-MAGSAT mission: A perspective on the problem of external/internal transient field effects

NASA Technical Reports Server (NTRS)

Hermance, J. F.

1985-01-01

The Earth's magnetic field at MAGSAT altitudes not only has contributions from the Earth's core and static magnetization in the lithosphere, but also from external electric current systems in the ionosphere and magnetosphere, along with induced electric currents flowing in the conducting earth. Hermance assessed these last two contributions; the external time-varying fields and their associated internal counter-parts which are electromagnetically induced. It is readily recognized that during periods of magnetic disturbance, external currents often contribute from 10's to 100's of nanoteslas (gammas) to observations of the Earth's field. Since static anomalies from lithospheric magnetization are of this same magnitude or less, these external source fields must be taken into account when attempting to delineate gross structural features in the crust.

Attribution of floods in the Okavango basin, Southern Africa

NASA Astrophysics Data System (ADS)

Wolski, Piotr; Stone, Dáithí; Tadross, Mark; Wehner, Michael; Hewitson, Bruce

2014-04-01

In the charismatic wetlands of the Okavango Delta, Botswana, the annual floods of 2009-2011 reached magnitudes last seen 20-30 years ago, considerably affecting life of local populations and the economically important tourism industry. In this study, we analyse results from an attribution modelling system designed to examine how anthropogenic greenhouse gas emissions have contributed to weather and flood risk in our current climate. The system is based on comparison of real world climate and hydrological simulations with parallel counterfactual simulations of the climate and hydrological responses under conditions that might have been had human activities not emitted greenhouse gases. The analyses allow us to address the question of whether anthropogenic climate change contributed to increasing the risk of these high flood events in the Okavango system. Results show that the probability of occurrence of high floods during 2009-2011 in the current climate is likely lower than it would have been in a climate without anthropogenic greenhouse gases. This result is robust across the two climate models and various data processing procedures, although the exact figures for the associated decrease in risk differ. Results also differ between the three years examined, indicating that the “time-slice” method used here needs to be applied to multiple years in order to accurately estimate the contribution of emissions to current risk. Simple sensitivity analyses indicate that the reduction in flood risk is attributed to higher temperatures (and thus evaporation) in the current world, with little difference in the analysed domain's rainfall simulated in the two scenarios.

Photoperiod Modulates Fast Delayed Rectifier Potassium Currents in the Mammalian Circadian Clock.

PubMed

Farajnia, Sahar; Meijer, Johanna H; Michel, Stephan

2016-10-01

One feature of the mammalian circadian clock, situated in the suprachiasmatic nucleus (SCN), is its ability to measure day length and thereby contribute to the seasonal adaptation of physiology and behavior. The timing signal from the SCN, namely the 24 hr pattern of electrical activity, is adjusted according to the photoperiod being broader in long days and narrower in short days. Vasoactive intestinal peptide and gamma-aminobutyric acid play a crucial role in intercellular communication within the SCN and contribute to the seasonal changes in phase distribution. However, little is known about the underlying ionic mechanisms of synchronization. The present study was aimed to identify cellular mechanisms involved in seasonal encoding by the SCN. Mice were adapted to long-day (light-dark 16:8) and short-day (light-dark 8:16) photoperiods and membrane properties as well as K + currents activity of SCN neurons were measured using patch-clamp recordings in acute slices. Remarkably, we found evidence for a photoperiodic effect on the fast delayed rectifier K + current, that is, the circadian modulation of this ion channel's activation reversed in long days resulting in 50% higher peak values during the night compared with the unaltered day values. Consistent with fast delayed rectifier enhancement, duration of action potentials during the night was shortened and afterhyperpolarization potentials increased in amplitude and duration. The slow delayed rectifier, transient K + currents, and membrane excitability were not affected by photoperiod. We conclude that photoperiod can change intrinsic ion channel properties of the SCN neurons, which may influence cellular communication and contribute to photoperiodic phase adjustment. © The Author(s) 2016.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko

In this study, we compute the gluon fusion Higgs boson cross-section at N 3LO through the second term in the threshold expansion. This calculation constitutes a major milestone towards the full N 3LO cross section. Our result has the best formal accuracy in the threshold expansion currently available, and includes contributions from collinear regions besides subleading corrections from soft and hard regions, as well as certain logarithmically enhanced contributions for general kinematics. We use our results to perform a critical appraisal of the validity of the threshold approximation at N 3LO in perturbative QCD.

Field-aligned current associated with a distorted two-cell convection pattern during northward interplanetary magnetic field

NASA Technical Reports Server (NTRS)

Zhu, L.; Schunk, R. W.; Sojka, J. J.

1991-01-01

The influence of the ionospheric conductance on the field-aligned current associated with a distorted two-cell convection pattern during northward IMF was investigated using the Heppner-Maynard (1987) convection model and the Utah State University conductivity model described by Rasmussen and Schunk (1987). Results show that the variation of the ionospheric conductivity distribution can significantly affect the features of the field-aligned current for northward IMF, where matching or mismatching between the conductance gradient and the convection electric field plays a key role. It was found that the increase of the field-aligned current in the polar cap observed during summer is mainly due to the increasing contribution from the Pedersen current, and that the increase of the field-aligned current in both the oval region and the evening-midnight sector during the active aurora period is mainly due to the increasing contribution from the Hall current.

The potential of ecological theory for building an integrated framework to develop the public health contribution of health visiting.

PubMed

Bryans, Alison; Cornish, Flora; McIntosh, Jean

2009-11-01

In line with recent UK and Scottish policy imperatives, there is increasing pressure for the health visiting service to assume an enhanced role in improving public health. Although health visiting has so far maintained its unique position as a primarily preventive service within the UK health service, its distinctive contribution now appears under threat. The continuing absence of a comprehensive and integrated conceptual basis for practice has a negative impact on the profession's ability to respond to current challenges. Establishing an integrative framework to conceptualise health visiting practice would enable more sensitive, focused and appropriate research, education and evaluation in relation to practice. Work in this area could thus usefully contribute to the future development of the service at a difficult time. Our paper aims to make such a contribution. In support of our conceptual aims, we draw on a study of health visiting practice undertaken within a large conurbation in central Scotland. The study used a mixed method, collaborative approach involving 12 audio-recorded and observed health visitor-client interactions, semi-structured interviews with the 12 HVs and 12 clients, examination of related documentation and workshops with the HV participants. We critically consider prevalent models of health visiting practice and describe the more integrative conceptual approach provided by Bronfenbrenner's ecological, 'person-in-context' framework. The paper subsequently explores relationships between this framework and understandings of need demonstrated by health visitors who participated in our study. Current policy emphasises the need to focus on public health and social inclusion in order to improve health. However, if this policy is to be translated into practice, we must develop a more adequate understanding of how practitioners work effectively with families and individuals in a sensitive and context-specific manner. Bronfenbrenner's framework appears to offer a promising means of building on the current strengths of the health visiting service to further develop a 'person-in-context' approach to health improvement that is mindful of and responsive to multiple, inter-related influences on health. We therefore recommend further research to directly test the utility of this framework.

Investigation of mode partition noise in Fabry-Perot laser diode

NASA Astrophysics Data System (ADS)

Guo, Qingyi; Deng, Lanxin; Mu, Jianwei; Li, Xun; Huang, Wei-Ping

2014-09-01

Passive optical network (PON) is considered as the most appealing access network architecture in terms of cost-effectiveness, bandwidth management flexibility, scalability and durability. And to further reduce the cost per subscriber, a Fabry-Perot (FP) laser diode is preferred as the transmitter at the optical network units (ONUs) because of its lower cost compared to distributed feedback (DFB) laser diode. However, the mode partition noise (MPN) associated with the multi-longitudinal-mode FP laser diode becomes the limiting factor in the network. This paper studies the MPN characteristics of the FP laser diode using the time-domain simulation of noise-driven multi-mode laser rate equation. The probability density functions are calculated for each longitudinal mode. The paper focuses on the investigation of the k-factor, which is a simple yet important measure of the noise power, but is usually taken as a fitted or assumed value in the penalty calculations. In this paper, the sources of the k-factor are studied with simulation, including the intrinsic source of the laser Langevin noise, and the extrinsic source of the bit pattern. The photon waveforms are shown under four simulation conditions for regular or random bit pattern, and with or without Langevin noise. The k-factors contributed by those sources are studied with a variety of bias current and modulation current. Simulation results are illustrated in figures, and show that the contribution of Langevin noise to the k-factor is larger than that of the random bit pattern, and is more dominant at lower bias current or higher modulation current.

Burnout in Special Needs Teachers at Kindergarten and Primary School: Investigating the Role of Personal Resources and Work Wellbeing

ERIC Educational Resources Information Center

De Stasio, Simona; Fiorilli, Caterina; Benevene, Paula; Uusitalo-Malmivaara, Lotta; Di Chiacchio, Carlo

2017-01-01

The purpose of the current study was to examine, within an integrative predictive model, the relative contributions of sociodemographic variables, personal resources, and work wellbeing to teacher burnout. The research was conducted with special education teachers at Italian preschools--a context in which few previous studies have been carried…

A Study of Sociolinguistic Variation in a Small Community: Puerto Rican Spanish in Amsterdam, New York

ERIC Educational Resources Information Center

Mumin, Zahir

2017-01-01

The objective of the current study is to contribute to the larger body of sociophonetic variation research by describing and analyzing Spanish as spoken in a small Puerto Rican community in the US. First, I describe phonological and morphosyntactic features of Spanish as used by four different groups of Puerto Rican informants in Amsterdam, New…

Brazil: Education in an Expanding Economy. Bulletin, 1959, No. 13

ERIC Educational Resources Information Center

Faust, Augustus F.

1959-01-01

Studies on education in other countries have long been a responsibility of the Office of Education. This present study is another contribution in the series. It is based on background information acquired by the author during 4 visits totaling 3 years of residence in Brazil, with a 1957 visit to obtain current first-hand data. The purpose of the…

Encoding and Retrieval Processes Involved in the Access of Source Information in the Absence of Item Memory

ERIC Educational Resources Information Center

Ball, B. Hunter; DeWitt, Michael R.; Knight, Justin B.; Hicks, Jason L.

2014-01-01

The current study sought to examine the relative contributions of encoding and retrieval processes in accessing contextual information in the absence of item memory using an extralist cuing procedure in which the retrieval cues used to query memory for contextual information were "related" to the target item but never actually studied.…

Risky Lifestyle as a Mediator of the Relationship between Deviant Peer Affiliation and Dating Violence Victimization among Adolescent Girls

ERIC Educational Resources Information Center

Vezina, Johanne; Hebert, Martine; Poulin, Francois; Lavoie, Francine; Vitaro, Frank; Tremblay, Richard E.

2011-01-01

Few studies have explored the possible contribution of the peer group to dating violence victimization. The current study tested the hypothesis that a risky lifestyle would mediate the relationship between deviant peer affiliation and dating violence victimization among adolescent girls. The proposed mediation model was derived from lifestyles and…

Spoken Word Recognition in School-Age Children with SLI: Semantic, Phonological, and Repetition Priming

ERIC Educational Resources Information Center

Velez, Melinda; Schwartz, Richard G.

2010-01-01

Purpose: The purpose of this study was to contribute to the current understanding of how children with specific language impairment (SLI) organize their mental lexicons. The study examined semantic and phonological priming in children with and without SLI. Method: Thirteen children (7;0-11;3 [years;months]) with SLI and 13 age-matched children…

Smearing the Opposition: Implicit and Explicit Stigmatization of the 2008 U. S. Presidential Candidates and the Current U. S. President

ERIC Educational Resources Information Center

Kosloff, Spee; Greenberg, Jeff; Schmader, Toni; Dechesne, Mark; Weise, David

2010-01-01

Four studies investigated whether political allegiance and salience of outgroup membership contribute to the phenomenon of acceptance of false, stigmatizing information (smears) about political candidates. Studies 1-3 were conducted in the month prior to the 2008 U.S. Presidential election and together demonstrated that pre-standing opposition to…

Video Game Access, Parental Rules, and Problem Behavior: A Study of Boys with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Engelhardt, Christopher R.; Mazurek, Micah O.

2014-01-01

Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to…

Environmental Literacy Components and Their Promotion by Institutions of Higher Education: An Israeli Case Study

ERIC Educational Resources Information Center

Arnon, Sara; Orion, Nir; Carmi, Nurit

2015-01-01

The recognition of the key role and moral responsibility of higher education institutions (HEIs) in cultivating the environmental literacy (EL) of their students is growing globally. The current research examined the contribution of HEIs to their students' EL by focusing on an Israeli college as a case-study. A survey was conducted among a…

Evaluation of the William S. Hall Psychiatric Institute Clinical Psychology Internship: a replication and extension.

PubMed

Stader, Sandra R; Myers, DeRosset; Forand, Angela Q; Holmes, George R; McNulty, George F; Frey, Linda; Bolton, Staci S

2010-12-01

This study extends three earlier investigations involving participants who completed their predoctoral clinical psychology internship at the William S. Hall Psychiatric Institute. Intern graduates (N = 37) evaluated how effectively their internship training prepared them for seven aspects of their current work as practicing psychologists. Participants also rated the relevancy of 24 different internship training experiences to their current work and how much these experiences contributed to their development as clinical psychologists. The present study, in conjunction with the three previous studies, covers most of the 40-year period since the inception of the internship program. Analysis of the current data indicates the internship has improved over time and was deemed an exceptional training experience by its graduates. Findings may be of particular interest to internship directors and faculty interested in improving their training program and those who plan to conduct a self-study to maintain their accreditation for clinical psychology internship.

What are the unique and interacting contributions of school and family factors to early adolescents' empathic concern and perspective taking?

PubMed

Batanova, Milena D; Loukas, Alexandra

2012-10-01

Empathy in children has received considerable attention in the literature, but limited research has investigated the contributions of various socializing factors on both affective (e.g., empathic concern) and cognitive (e.g., perspective taking) components of empathy in early adolescents. Guided by socialization theories, this study examined the unique and interacting contributions of school connectedness and parent-child conflict to subsequent levels of both components of empathy across a 1-year period of time. Participants were 487 10- to 14- year old middle school students (54 % female; 76 % European-American) involved in two waves of a study with 1 year between each wave. Hierarchical regression analyses indicated that, among girls, reports of parent-child conflict contributed to a decrease in empathic concern one year later, whereas school connectedness was a protective factor that offset the negative impact of parent-child conflict on girls' subsequent perspective taking. Alternatively, only boys' reports of school connectedness contributed to subsequent increases in both empathic concern and perspective taking 1 year later. Findings indicate that school connectedness and conflict with parents play different socializing roles for girls' and boys' empathic concern and perspective taking. The current study calls for further research and youth programs to consider the important contributions that socializing agents can make on both components of empathy for early adolescent girls and boys.

The contribution of cationic conductances to the potential of rod photoreceptors.

PubMed

Moriondo, Andrea; Rispoli, Giorgio

2010-05-01

The contribution of cationic conductances in shaping the rod photovoltage was studied in light adapted cells recorded under whole-cell voltage- or current-clamp conditions. Depolarising current steps (of size comparable to the light-regulated current) produced monotonic responses when the prepulse holding potential (V (h)) was -40 mV (i.e. corresponding to the membrane potential in the dark). At V (h) = -60 mV (simulating the steady-state response to an intense background of light) current injections <35 pA (mimicking a light decrement) produced instead an initial depolarisation that declined to a plateau, and voltage transiently overshot V (h) at the stimulus offset. Current steps >40 pA produced a steady depolarisation to approximately -16 mV at both V (h). The difference between the responses at the two V (h) was primarily generated by the slow delayed-rectifier-like K(+) current (I (Kx)), which therefore strongly affects both the photoresponse rising and falling phase. The steady voltage observed at both V (h) in response to large current injections was instead generated by Ca-activated K(+) channels (I (KCa)), as previously found. Both I (Kx) and I (KCa) oppose the cation influx, occurring at the light stimulus offset through the cGMP-gated channels and the voltage-activated Ca(2+) channels (I (Ca)). This avoids that the cation influx could erratically depolarise the rod past its normal resting value, thus allowing a reliable dim stimuli detection, without slowing down the photovoltage recovery kinetics. The latter kinetics was instead accelerated by the hyperpolarisation-activated, non-selective current (I (h)) and I (Ca). Blockade of all K(+) currents with external TEA unmasked a I (Ca)-dependent regenerative behaviour.

Incentive-Related Modulation of Cognitive Control in Healthy, Anxious, and Depressed Adolescents: Development and Psychopathology Related Differences

ERIC Educational Resources Information Center

Hardin, Michael G.; Schroth, Elizabeth; Pine, Daniel S.; Ernst, Monique

2007-01-01

Background: Developmental changes in cognitive and affective processes contribute to adolescent risk-taking behavior, emotional intensification, and psychopathology. The current study examined adolescent development of cognitive control processes and their modulation by incentive, in health and psychopathology. Predictions include 1) better…

Synthesizing Technology Adoption and Learners' Approaches towards Active Learning in Higher Education

ERIC Educational Resources Information Center

Chan, Kevin; Cheung, George; Wan, Kelvin; Brown, Ian; Luk, Green

2015-01-01

In understanding how active and blended learning approaches with learning technologies engagement in undergraduate education, current research models tend to undermine the effect of learners' variations, particularly regarding their styles and approaches to learning, on intention and use of learning technologies. This study contributes to further…

Engineering Education Problems. The Laboratory Equipment Factor.

ERIC Educational Resources Information Center

National Society of Professional Engineers, Washington, DC.

Presented is a pilot study focusing attention on problems of deteriorating physical plants and inadequate/obsolete equipment contributing to the current crisis in engineering education. Data are reported from a survey instrument (included in an appendix) from 26 colleges/universities, representing 168 programs out of a national total of 1212…

Phosphorus Adsorption and Desorption During and After Swine Manure Spill Simulations

USDA-ARS?s Scientific Manuscript database

Manure spills contribute phosphorus (P) to surface waters during catastrophic events and little is known about the effectiveness of the current manure spill remediation methods with regard to the water column and sediments within the fluvial system. Therefore, the objectives of this study were to (1...

Transport and Fate of Phosphorus During and After Manure Spill Simulations

USDA-ARS?s Scientific Manuscript database

Manure spills contribute phosphorus (P) to surface waters during catastrophic events and little is known about the effectiveness of the current manure spill remediation methods with regard to the water column and sediments within the fluvial system. Therefore, the objectives of this study were to (1...

Ability and Motivation: Assessing Individual Factors that Contribute to University Retention

ERIC Educational Resources Information Center

Alarcon, Gene M.; Edwards, Jean M.

2013-01-01

The current study explored individual differences in ability and motivation factors of retention in first-year college students. We used discrete-time survival mixture analysis to model university retention. Parents' education, gender, American College Test (ACT) scores, conscientiousness, and trait affectivity were explored as predictors of…

Women's Perspectives of Peace: Unheard Voices from Pakistan

ERIC Educational Resources Information Center

Habib, Zehra

2013-01-01

Pakistan is currently impacted by rampant terrorism and is simultaneously grappling with intrastate ethnic and sectarian violence. The focus of this dissertation was on examining grassroots Pakistani women's perspectives on peace and women's contributions to peace in Pakistan. The study was centered on grassroots women because their voices remain…

Parents' Beliefs about Peer Victimization and Children's Socio-Emotional Development

ERIC Educational Resources Information Center

Troop-Gordon, Wendy; Gerardy, Haeli

2012-01-01

There is increasing evidence that interpersonal risks and resources can modulate the impact peer victimization has on children's socio-emotional adjustment. The current study contributes to this research by examining links between parents' victimization-related beliefs and children's psychosocial functioning. Data were collected on 190 3rd- and…

Philanthropic Motivations of Community College Donors

ERIC Educational Resources Information Center

Carter, Linnie S.; Duggan, Molly H.

2011-01-01

This descriptive study surveyed current, lapsed, and major gift donors to explore the impact of college communications on donors' decisions to contribute to the college, the likelihood of donor financial support for various college projects, and the philanthropic motivation profiles of the donors of a midsized, multicampus community college in…

General Intelligence Predicts Reasoning Ability Even for Evolutionarily Familiar Content

ERIC Educational Resources Information Center

Kaufman, Scott Barry; DeYoung, Colin G.; Reis, Deidre L.; Gray, Jeremy R.

2011-01-01

The existence of general-purpose cognitive mechanisms related to intelligence, which appear to facilitate all forms of problem solving, conflicts with the strong modularity view of the mind espoused by some evolutionary psychologists. The current study assessed the contribution of general intelligence ("g") to explaining variation in…

Volcanic gases create air pollution on the Island of Hawai’i

USGS Publications Warehouse

Sutton, J.; Elias, T.

1993-01-01

The current eruption of Kilauea produces large quantities of volcanic gases that contribute to "volcanic air pollution." In this article we discuss the nature of the gases released from Kilauea, hoe we study them, and what happened to the gases in the environment after they are released. 

Agreement Reflexes of Emerging Optionality in Heritage Speaker Spanish

ERIC Educational Resources Information Center

Pascual Cabo, Diego

2013-01-01

This study contributes to current trends of heritage speaker (HS) acquisition research by examining the syntax of psych-predicates in HS Spanish. Broadly defined, psych-predicates communicate states of emotions (e.g., to love) and have traditionally been categorized as belonging to one of three classes: class I--"temere" "to…

Operation Compatibility: A Neglected Contribution to Dual-Task Costs

ERIC Educational Resources Information Center

Pannebakker, Merel M.; Band, Guido P. H.; Ridderinkhof, K. Richard

2009-01-01

Traditionally, dual-task interference has been attributed to the consequences of task load exceeding capacity limitations. However, the current study demonstrates that in addition to task load, the mutual compatibility of the concurrent processes modulates whether 2 tasks can be performed in parallel. In 2 psychological refractory period…

Seasonal and cryopreservation impacts on semen quality in boars

USDA-ARS?s Scientific Manuscript database

Seasonal boar infertility occurs worldwide and contributes to economic loss to the pork industry. The current study evaluated cooled vs cryopreserved semen quality of 11 Duroc boars collected in June (cool season) and August 2014 (warm season). Semen was cooled to 16°C (cooled) or frozen over liquid...

An Empirical Taxonomy of Social-Psychological Risk Indicators in Youth Suicide

ERIC Educational Resources Information Center

Hyde, Toni; Kirkland, John; Bimler, David; Pechtel, Pia

2005-01-01

The current study integrates descriptive (though primarily social-psychological) statements about youth suicide into a coherent, empirically supported taxonomy. Drawing from relevant literature, a set of 107 items characterizing these contributions about youth suicide was created. Seventy-two participants sorted these statements according to their…

Auditory Phoneme Discrimination in Illiterates: Mismatch Negativity--A Question of Literacy?

ERIC Educational Resources Information Center

Schaadt, Gesa; Pannekamp, Ann; van der Meer, Elke

2013-01-01

These days, illiteracy is still a major problem. There is empirical evidence that auditory phoneme discrimination is one of the factors contributing to written language acquisition. The current study investigated auditory phoneme discrimination in participants who did not acquire written language sufficiently. Auditory phoneme discrimination was…

Goal Expectations as Predictors of Retirement Intentions

ERIC Educational Resources Information Center

Brougham, Ruby R.; Walsh, David A.

2005-01-01

The current study explored the contribution of personal goals to retirement decisions. A SMARTER methodology (to assess multiattribute utility) and taxonomy of human goals were used to investigate the relationship between older workers' personal goals and their retirement intentions. Two hundred and fifty-one employees of a large university,…

Identity Exploration and Commitment in Early Adolescence: Genetic and Environmental Contributions

ERIC Educational Resources Information Center

Markovitch, Noam; Luyckx, Koen; Klimstra, Theo; Abramson, Lior; Knafo-Noam, Ariel

2017-01-01

Identity formation is a key developmental task in adolescence. Although many adolescents in modern societies face issues of identity, there are substantial individual differences in identity exploration and commitment. Little is known about the origins of these individual differences. The current study investigated the genetic and environmental…

Evaluation of contributions to seasonal reproductive inefficiency; NPB project #14-052

USDA-ARS?s Scientific Manuscript database

The objective of the current study was to evaluate quality of semen collected from June (spring), August (summer), or January (winter) and either stored and used as cooled-extended (ExT) or cryopreserved (FrZ) for breeding gilts in summer (August) or winter (January). Semen quality evaluation includ...

A Place to Learn: Cultivating Engaging Learning Environments for Young Rural Aboriginal Australians

ERIC Educational Resources Information Center

Tracey, Danielle; Craven, Rhonda G.; Yeung, Alexander Seeshing; Tregeagle, Susan; Burnstein, Jodi; Stanley, Helena

2016-01-01

Rural Aboriginal Australians experience disadvantage across a number of significant social and economic outcomes, including educational engagement and achievement. Current debate postulates that educational environments and systems perpetuate this disadvantage. This qualitative study aimed to contribute to the debate by taking a broader ecological…

Measuring Arithmetic: A Psychometric Approach to Understanding Formatting Effects and Domain Specificity

ERIC Educational Resources Information Center

Rhodes, Katherine T.; Branum-Martin, Lee; Washington, Julie A.; Fuchs, Lynn S.

2017-01-01

Using multitrait, multimethod data, and confirmatory factor analysis, the current study examined the effects of arithmetic item formatting and the possibility that across formats, abilities other than arithmetic may contribute to children's answers. Measurement hypotheses were guided by several leading theories of arithmetic cognition. With a…

Father Contributions to Cortisol Responses in Infancy and Toddlerhood

ERIC Educational Resources Information Center

Mills-Koonce, W. Roger; Garrett-Peters, Patricia; Barnett, Melissa; Granger, Douglas A.; Blair, Clancy; Cox, Martha J.

2011-01-01

The current study is one of the first prospective examinations of longitudinal associations between observed father caregiving behaviors and child cortisol reactivity and regulation in response to emotional arousal. Observations of father and mother caregiving behaviors and child cortisol levels in response to challenges at 7 months and 24 months…

Teacher Turnover in Charter Schools. Research Brief

ERIC Educational Resources Information Center

Stuit, David; Smith, Thomas M.

2010-01-01

The current study aimed to contribute to a deeper understanding of the organizational conditions of charter schools by examining teacher turnover. Using data from the National Center for Education Statistics (NCES) 2003-04 Schools and Staffing Survey (SASS) and the Teacher Follow-Up Survey (TFS), researchers from the National Center on School…

Design and Development of Web-Based Information Literacy Tutorials

ERIC Educational Resources Information Center

Su, Shiao-Feng; Kuo, Jane

2010-01-01

The current study conducts a thorough content analysis of recently built or up-to-date high-quality web-based information literacy tutorials contributed by academic libraries in a peer-reviewed database, PRIMO. This research analyzes the topics/skills PRIMO tutorials consider essential and the teaching strategies they consider effective. The…

The Contribution of Attentional Control and Working Memory to Reading Comprehension and Decoding

ERIC Educational Resources Information Center

Arrington, C. Nikki; Kulesz, Paulina A.; Francis, David J.; Fletcher, Jack M.; Barnes, Marcia A.

2014-01-01

Little is known about how specific components of working memory, namely, attentional processes including response inhibition, sustained attention, and cognitive inhibition, are related to reading decoding and comprehension. The current study evaluated the relations of reading comprehension, decoding, working memory, and attentional control in…

Montessori and Nature Study: Preserving Wonder through School Gardens

ERIC Educational Resources Information Center

Johnson, Kelly

2013-01-01

Current research suggests that nature experience and the cultivation of environmental literacy among students contributes to creative thinking, improved academic performance, and positive relationships with the natural world (Children and Nature Network, retrieved June 2013). Author Kelley Johnson saw this in her own childhood, which was blessed…

The Shared Principalship: Invitation at the Top

ERIC Educational Resources Information Center

Döös, Marianne; Wilhelmson, Lena; Madestam, Jenny; Örnberg, Åsa

2018-01-01

A school principal's workload is recognised as being heavy, with an imbalance between demands and resources. This paper contributes to the development of collective leadership. The principalship constellations of six schools in Sweden were studied with the aim of strengthening the current knowledge about structures and experiences of shared…

High School Students' Attributions of Success in English Language Learning

ERIC Educational Resources Information Center

Bouchaib, Benzehaf; Ahmadou, Bouylmani; Abdelkader, Sabil

2018-01-01

Research into students' attributional causes for success in language acquisition is currently receiving considerable attention. Situated within Weiner's attribution theory (1992), the present study aims to research factors contributing to success in foreign language learning with specific focus on the role of perceived causal attributions. The…

Parenting Latino Toddlers and Preschoolers: Clinical and Nonclinical Samples

ERIC Educational Resources Information Center

Perez, Maria E.; Fox, Robert A.

2008-01-01

Parenting practices contribute significantly to the social-emotional development of young children. There is limited literature that addresses the role of culture in parenting, particularly among Latino families who have very young children with significant behavior problems. The current study compared the parenting practices of 30 low-income…

Learning Gains in Lab Practices: Teach Science Doing Science

ERIC Educational Resources Information Center

Dopico, Eduardo; Linde, Ana R.; Garcia-Vazquez, Eva

2014-01-01

Introducing research in undergraduate biology studies may contribute to creating research vocations and generate the idea that science may influence all aspects of common life. However, laboratory practices are too often disconnected from current investigations and rarely address real-life questions that are really interesting for students.…

Concepts for Care: 20 Essays on Infant/Toddler Development and Learning

ERIC Educational Resources Information Center

Lally, J. Ronald, Ed.; Mangione, Peter L., Ed.; Greenwald, Deborah, Ed.

2006-01-01

Leading experts in infant/toddler development have contributed succinct essays drawn from research, theory, clinical case studies, and carefully documented practice. Each essay represents current thinking in the field of infant/toddler development and care. Individually and as a collection, the essays provide a springboard for reflection,…

An Analysis of the Effectiveness of University Counselling Services

ERIC Educational Resources Information Center

Murray, Aja L.; McKenzie, Karen; Murray, Kara R.; Richelieu, Marc

2016-01-01

It is important to demonstrate replicable evidence of the effectiveness of counselling procedures. The study aimed to contribute to the currently limited evidence base examining the effectiveness of university student counselling in the UK. Information on therapeutic outcome [based on Clinical Outcomes in Routine Evaluation-Outcome Measure…

Correlation of Understanding of Physics and Psychological Symptoms among High-School Students in Greece

ERIC Educational Resources Information Center

Aggeliki, Anagnostopoulou; Miltiades, Kyprianou; Antigoni-Elisavet, Rota; Evangelia, Pavlatou; Loizos, Zaphiris

2017-01-01

Depression may essentially influence cognitive function contributing to poor school performance. The present study undertakes to determine the existence and strength of correlation between depressive symptomatology and other mental conditions with the acquired level of understanding of Newtonian physics taught in schools. The current study…

REPEATED MATERNAL SEPARATION IN THE NEONATAL RAT: CELLULAR MECHANISMS CONTRIBUTING TO BRAIN GROWTH SPARING

EPA Science Inventory

Separation of rat neonates from their dam has been shown to evoke acutely a variety of biochemical and physiological responses. n the current study, we examined whether these responses were extended to pups who were subject to daily episodes of maternal deprivation, and whether t...

An International Review of Autism Knowledge Assessment Measures

ERIC Educational Resources Information Center

Harrison, Ashley J.; Slane, Mylissa M.; Hoang, Linh; Campbell, Jonathan M.

2017-01-01

Autism spectrum disorder-specific knowledge deficits contribute to current disparities in the timing and quality of autism spectrum disorder services throughout the United States and globally. This study conducted a systematic review of Western and International literature to examine measures used to assess autism spectrum disorder knowledge. This…

Award-Winning Faculty at a Faith-Based Institution

ERIC Educational Resources Information Center

Livingston, Jennifer; Jun, Alexander

2011-01-01

Exploring the development of excellent teachers could contribute to the revision of current practices in faculty recruitment, evaluation, workload expectations, and reward systems. This grounded theory study examined the professional careers of nine award-winning faculty members of a faith-based institution of higher education. The data, collected…

Higher Education and Employability: New Models for Integrating Study and Work

ERIC Educational Resources Information Center

Stokes, Peter J.

2015-01-01

"Higher Education and Employability" makes a crucial contribution to the current reassessment of higher education in the United States by focusing on how colleges and universities can collaborate with businesses in order to serve the educational and professional interests of their students. Drawing on his extensive experience with…

Learning about Teachers' Literacy Instruction from Classroom Observations

ERIC Educational Resources Information Center

Kelcey, Ben; Carlisle, Joanne F.

2013-01-01

The purpose of this study is to contribute to efforts to improve methods for gathering and analyzing data from classroom observations in early literacy. The methodological approach addresses current problems of reliability and validity of classroom observations by taking into account differences in teachers' uses of instructional actions (e.g.,…

A Survey of Library Support for Formal Undergraduate Research Programs

ERIC Educational Resources Information Center

Hensley, Merinda Kaye; Shreeves, Sarah L.; Davis-Kahl, Stephanie

2014-01-01

Undergraduate research is defined by the Council on Undergraduate Research (CUR) as "an inquiry or investigation conducted by an undergraduate student that makes an original intellectual or creative contribution to the discipline." This study serves as a snapshot of current library practices in relation to formal undergraduate research…

Prosocial Involvement among African American Young Adults: Considering Racial Discrimination and Racial Identity

ERIC Educational Resources Information Center

White-Johnson, Rhonda L.

2012-01-01

Prosocial involvement is conceptualized as support for or engaging in behaviors that contribute to or benefit African American communities. The current study examines the relationship between prosocial involvement and race-related factors among 303 African American college students. Using two underlying dimensions of prosocial involvement,…

Fair Share or Freeride: Burden Sharing in Post-Cold War NATO

DTIC Science & Technology

2015-05-23

military facilities in Europe. 56 Carl Elk, NATO Common Funds Burdensharing: Background and Current Issues (Washington DC: Congressional Research...Defense Minister Franz Joseph Jung replied, “our contribution is excellent.”114 Germany was clearly proud of its contribution to NATO operations, but...Monsanto, Portugal: NATO Joint Analysis Lessons Learned Centre (JALLC), 2011. Elk, Carl . NATO Common Funds Burdensharing: Background and Current

QCD sum-rules analysis of vector (1-) heavy quarkonium meson-hybrid mixing

NASA Astrophysics Data System (ADS)

Palameta, A.; Ho, J.; Harnett, D.; Steele, T. G.

2018-02-01

We use QCD Laplace sum rules to study meson-hybrid mixing in vector (1-) heavy quarkonium. We compute the QCD cross-correlator between a heavy meson current and a heavy hybrid current within the operator product expansion. In addition to leading-order perturbation theory, we include four- and six-dimensional gluon condensate contributions as well as a six-dimensional quark condensate contribution. We construct several single and multiresonance models that take known hadron masses as inputs. We investigate which resonances couple to both currents and so exhibit meson-hybrid mixing. Compared to single resonance models that include only the ground state, we find that models that also include excited states lead to significantly improved agreement between QCD and experiment. In the charmonium sector, we find that meson-hybrid mixing is consistent with a two-resonance model consisting of the J /ψ and a 4.3 GeV resonance. In the bottomonium sector, we find evidence for meson-hybrid mixing in the ϒ (1 S ) , ϒ (2 S ), ϒ (3 S ), and ϒ (4 S ).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krebs, H., E-mail: hermann.krebs@rub.de; Epelbaum, E., E-mail: evgeny.epelbaum@rub.de; Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93016

We present the complete derivation of the nuclear axial charge and current operators as well as the pseudoscalar operators to fourth order in the chiral expansion relative to the dominant one-body contribution using the method of unitary transformation. We demonstrate that the unitary ambiguity in the resulting operators can be eliminated by the requirement of renormalizability and by matching of the pion-pole contributions to the nuclear forces. We give expressions for the renormalized single-, two- and three-nucleon contributions to the charge and current operators and pseudoscalar operators including the relevant relativistic corrections. We also verify explicitly the validity of themore » continuity equation.« less

Absence of anomalous Nernst effect in spin Seebeck effect of Pt/YIG

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miao, B. F., E-mail: bfmiao@nju.edu.cn; Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218; Huang, S. Y.

2016-01-15

The Pt/YIG structure has been widely used to study spin Seebeck effect (SSE), inverse spin Hall effect, and other pure spin current phenomena. However, the magnetic proximity effect in Pt when in contact with YIG, and the potential anomalous Nernst effect (ANE) may compromise the spin current phenomena in Pt/YIG. By inserting a Cu layer of various thicknesses between Pt and YIG, we have separated the signals from the SSE and that of the ANE. It is demonstrated that the thermal voltage in Pt/YIG mainly comes from spin current due to the longitudinal SSE with negligible contribution from the ANE.

Role of Ureaplasma Respiratory Tract Colonization in BPD Pathogenesis: Current Concepts and Update

PubMed Central

Viscardi, Rose Marie; Kallapur, Suhas G.

2015-01-01

SYNOPSIS Respiratory tract colonization with the genital mycoplasma species Ureaplasma parvum and U. urealyticum in preterm infants is a significant risk factor for BPD. Recent studies of the ureaplasmal genome, animal infection models, and human infants have provided a better understanding of specific virulence factors, pathogen-host interactions, and variability in genetic susceptibility that contribute to chronic infection, inflammation, and altered lung development. This review will provide an update on the current evidence supporting a causal role of Ureaplasma infection in BPD pathogenesis. The current status of antibiotic trials to prevent BPD in Ureaplasma-infected preterm infants is also reviewed. PMID:26593075

Theoretical and experimental studies of error in square-law detector circuits

NASA Technical Reports Server (NTRS)

Stanley, W. D.; Hearn, C. P.; Williams, J. B.

1984-01-01

Square law detector circuits to determine errors from the ideal input/output characteristic function were investigated. The nonlinear circuit response is analyzed by a power series expansion containing terms through the fourth degree, from which the significant deviation from square law can be predicted. Both fixed bias current and flexible bias current configurations are considered. The latter case corresponds with the situation where the mean current can change with the application of a signal. Experimental investigations of the circuit arrangements are described. Agreement between the analytical models and the experimental results are established. Factors which contribute to differences under certain conditions are outlined.

Upregulation of T-type Ca2+ channels in long-term diabetes determines increased excitability of a specific type of capsaicin-insensitive DRG neurons.

PubMed

Duzhyy, Dmytro E; Viatchenko-Karpinski, Viacheslav Y; Khomula, Eugen V; Voitenko, Nana V; Belan, Pavel V

2015-05-20

Previous studies have shown that increased excitability of capsaicin-sensitive DRG neurons and thermal hyperalgesia in rats with short-term (2-4 weeks) streptozotocin-induced diabetes is mediated by upregulation of T-type Ca(2+) current. In longer-term diabetes (after the 8th week) thermal hyperalgesia is changed to hypoalgesia that is accompanied by downregulation of T-type current in capsaicin-sensitive small-sized nociceptors. At the same time pain symptoms of diabetic neuropathy other than thermal persist in STZ-diabetic animals and patients during progression of diabetes into later stages suggesting that other types of DRG neurons may be sensitized and contribute to pain. In this study, we examined functional expression of T-type Ca(2+) channels in capsaicin-insensitive DRG neurons and excitability of these neurons in longer-term diabetic rats and in thermally hypoalgesic diabetic rats. Here we have demonstrated that in STZ-diabetes T-type current was upregulated in capsaicin-insensitive low-pH-sensitive small-sized nociceptive DRG neurons of longer-term diabetic rats and thermally hypoalgesic diabetic rats. This upregulation was not accompanied by significant changes in biophysical properties of T-type channels suggesting that a density of functionally active channels was increased. Sensitivity of T-type current to amiloride (1 mM) and low concentration of Ni(2+) (50 μM) implicates prevalence of Cav3.2 subtype of T-type channels in the capsaicin-insensitive low-pH-sensitive neurons of both naïve and diabetic rats. The upregulation of T-type channels resulted in the increased neuronal excitability of these nociceptive neurons revealed by a lower threshold for action potential initiation, prominent afterdepolarizing potentials and burst firing. Sodium current was not significantly changed in these neurons during long-term diabetes and could not contribute to the diabetes-induced increase of neuronal excitability. Capsaicin-insensitive low-pH-sensitive type of DRG neurons shows diabetes-induced upregulation of Cav3.2 subtype of T-type channels. This upregulation results in the increased excitability of these neurons and may contribute to nonthermal nociception at a later-stage diabetes.

Transcranial direct-current stimulation induced in stroke patients with aphasia: a prospective experimental cohort study.

PubMed

Santos, Michele Devido; Gagliardi, Rubens José; Mac-Kay, Ana Paula Machado Goyano; Boggio, Paulo Sergio; Lianza, Roberta; Fregni, Felipe

2013-01-01

Previous animal and human studies have shown that transcranial direct current stimulation can induce significant and lasting neuroplasticity and may improve language recovery in patients with aphasia. The objective of the study was to describe a cohort of patients with aphasia after stroke who were treated with transcranial direct current stimulation. Prospective cohort study developed in a public university hospital. Nineteen patients with chronic aphasia received 10 transcranial direct current stimulation sessions lasting 20 minutes each on consecutive days, using a current of 2 mA. The anode was positioned over the supraorbital area and the cathode over the contralateral motor cortex. The following variables were analyzed before and after the 10 neuromodulation sessions: oral language comprehension, copying, dictation, reading, writing, naming and verbal fluency. There were no adverse effects in the study. We found statistically significant differences from before to after stimulation in relation to simple sentence comprehension (P = 0.034), naming (P = 0.041) and verbal fluency for names of animals (P = 0.038). Improved scores for performing these three tasks were seen after stimulation. We observed that excitability of the primary motor cortex through transcranial direct current stimulation was associated with effects on different aspects of language. This can contribute towards future testing in randomized controlled trials.

Spontaneous recombination current in InGaAs/GaAs quantum well lasers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blood, P.; Fletcher, E.D.; Woodbridge, K.

1990-10-08

We have studied the intrinsic factors which determine the threshold current and its temperature dependence in 160-A-wide In{sub 0.2}Ga{sub 0.8}As single well quantum lasers with GaAs barriers, grown by molecular beam epitaxy on GaAs substrates. By measuring the relative temperature dependence of the spontaneous emission intensity at threshold we show that radiative transitions between higher order ({ital n}=2,3) electron and heavy hole subbands make a significant contribution to the threshold current and its temperature sensitivity, even in devices where the laser transitions are between {ital n}=1 subbands. These higher transitions will also influence the dependence of threshold current and itsmore » temperature sensitivity on well width.« less

5 CFR 1605.14 - Misclassified retirement system coverage.

Code of Federal Regulations, 2010 CFR

2010-01-01

... is a FERCCA correction, the employing agency must submit makeup employee contributions on late... correction, the employing agency must submit makeup employee contributions on current payment records; in such cases, the employee is not entitled to breakage. Agency makeup contributions may be submitted on...

Support for adolescent spirituality: contributions of religious practice and trait mindfulness.

PubMed

Cobb, Eleanor; Kor, Ariel; Miller, Lisa

2015-06-01

Spirituality and the surge of its development in adolescence have been established in the research. To date, however, these studies look at tendencies across full samples of adolescence rather than investigating multiple subgroups or multiple pathways of spiritual development. The current study uses latent class analysis to identify subgroup portraits of spiritual life in adolescence, based upon a range of dimensions of spiritual experience, religious practice, and mindfulness. Mindfulness, as a dispositional trait, is examined alongside the impact of religious practice on the level of spiritual experience (relationship with the Higher Power, spiritual values, and spiritual self). The findings suggest there is a complimentary contribution to spiritual life in adolescence from religious practice and mindfulness, with both as supportive pathways for spiritual development. Adolescents with the highest level of spiritual experience benefit from both religious practice and trait mindfulness, suggesting that taken together, there is an additive and augmenting contribution.

Implications of genome wide association studies for addiction: are our a priori assumptions all wrong?

PubMed

Hall, F Scott; Drgonova, Jana; Jain, Siddharth; Uhl, George R

2013-12-01

Substantial genetic contributions to addiction vulnerability are supported by data from twin studies, linkage studies, candidate gene association studies and, more recently, Genome Wide Association Studies (GWAS). Parallel to this work, animal studies have attempted to identify the genes that may contribute to responses to addictive drugs and addiction liability, initially focusing upon genes for the targets of the major drugs of abuse. These studies identified genes/proteins that affect responses to drugs of abuse; however, this does not necessarily mean that variation in these genes contributes to the genetic component of addiction liability. One of the major problems with initial linkage and candidate gene studies was an a priori focus on the genes thought to be involved in addiction based upon the known contributions of those proteins to drug actions, making the identification of novel genes unlikely. The GWAS approach is systematic and agnostic to such a priori assumptions. From the numerous GWAS now completed several conclusions may be drawn: (1) addiction is highly polygenic; each allelic variant contributing in a small, additive fashion to addiction vulnerability; (2) unexpected, compared to our a priori assumptions, classes of genes are most important in explaining addiction vulnerability; (3) although substantial genetic heterogeneity exists, there is substantial convergence of GWAS signals on particular genes. This review traces the history of this research; from initial transgenic mouse models based upon candidate gene and linkage studies, through the progression of GWAS for addiction and nicotine cessation, to the current human and transgenic mouse studies post-GWAS. © 2013.

Methicillin-resistant food-related Staphylococcus aureus: a review of current knowledge and biofilm formation for future studies and applications.

PubMed

Doulgeraki, Agapi I; Di Ciccio, Pierluigi; Ianieri, Adriana; Nychas, George-John E

2017-01-01

There is increasing concern about the public health impact of methicillin-resistant Staphylococcus aureus. Food and animal are vectors of transmission, but the contribution of a contaminated environment is not well characterized. With regard to this, staphylococcal biofilms serve as a virulence factor, allowing MRSA strains to adhere to surfaces and other materials used in the food industry. Methicillin resistance and biofilm-forming capacity may contribute to the success of S. aureus as a human pathogen in both health care and community settings and the food production chain. This review summarizes current knowledge about the significance of food- and animal-derived MRSA strains and provides data on attachment and biofilm formation of MRSA. In addition, the impact of quorum sensing on MRSA gene expression and biofilm formation is examined. Copyright © 2016. Published by Elsevier Masson SAS.

Plant Metabolomics: An Indispensable System Biology Tool for Plant Science

PubMed Central

Hong, Jun; Yang, Litao; Zhang, Dabing; Shi, Jianxin

2016-01-01

As genomes of many plant species have been sequenced, demand for functional genomics has dramatically accelerated the improvement of other omics including metabolomics. Despite a large amount of metabolites still remaining to be identified, metabolomics has contributed significantly not only to the understanding of plant physiology and biology from the view of small chemical molecules that reflect the end point of biological activities, but also in past decades to the attempts to improve plant behavior under both normal and stressed conditions. Hereby, we summarize the current knowledge on the genetic and biochemical mechanisms underlying plant growth, development, and stress responses, focusing further on the contributions of metabolomics to practical applications in crop quality improvement and food safety assessment, as well as plant metabolic engineering. We also highlight the current challenges and future perspectives in this inspiring area, with the aim to stimulate further studies leading to better crop improvement of yield and quality. PMID:27258266

Electromagnetic deep-probing (100-1000 kms) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F.

1983-01-01

The reconnaissance phase of using satellite observtions to studying electromagnetic induction in the solid earth is summarized. Several points are made: (1) satellite data apparently suffer far less from the effects of near surface lateral heterogeneities in the earth than do ground-based data; (2) zonal ionospheric currents during the recovery phase of major magnetic storms appear to be minimal, at least in the dawn and dusk sectors wher MAGSAT was flown; hence the internal contributions that satellites observe during these times is in fact due primarily to induction in the Earth with little or no contribution from ionospheric currents; and (3) the interpretation of satellite data in terms of primitive electromagnetic response functions, while grossly over-simplified, results in a surprisingly well-resolved radius for an equivalent super-conductor representing the conductivity region of the Earth's interior (5,370 + or - 120 km).

Insight into the contribution of isoprostanoids to the health effects of omega 3 PUFAs.

PubMed

Joumard-Cubizolles, Laurie; Lee, Jetty Chung-Yung; Vigor, Claire; Leung, Ho Hang; Bertrand-Michel, Justine; Galano, Jean-Marie; Mazur, André; Durand, Thierry; Gladine, Cecile

2017-11-01

Omega 3 polyunsaturated fatty acids have been reported to confer beneficial health effects notably in the field of cardiovascular and inflammatory diseases. The current knowledge suggests a significant portion of the effects of omega 3 polyunsaturated fatty acids are mediated by their oxygenated metabolites. This review attempts to cover the current literature about the contribution of specific omega 3 oxygenated metabolites, namely omega 3 isoprostanoids, which are produced through free-radical mediated oxidation. A special emphasis has been given to the most biologically relevant omega 3 polyunsaturated fatty acids namely the α-linolenic, eicosapentaenoic and docosahexaenoic acids. The review includes a comprehensive description of the biosynthetic pathways, a summary of studies related to the biological significance of omega 3 isoprostanoids as well as a critical description of analytical development in the field of omega 3 isoprostanoids profiling in biological samples. Copyright © 2017 Elsevier Inc. All rights reserved.

Problematizing Disciplinarity, Transdisciplinary Problematics.

PubMed

Osborne, Peter

2015-09-01

This article situates current debates about transdisciplinarity within the deeper history of academic disciplinarity, in its difference from the notions of inter- and multi-disciplinarity. It offers a brief typology and history of established conceptions of transdisciplinarity within science and technology studies. It then goes on to raise the question of the conceptual structure of transdisciplinary generality in the humanities, with respect to the incorporation of the 19th- and 20th-century German and French philosophical traditions into the anglophone humanities, under the name of 'theory'. It identifies two distinct - dialectical and anti-dialectical, or dialectical and transversal - transdisciplinary trajectories. It locates the various contributions to the special issue of which it is the introduction within this conceptual field, drawing attention to the distinct contribution of the French debates about structuralism and its aftermath - those by Serres, Foucault, Derrida, Guattari and Latour, in particular. It concludes with an appendix on Foucault's place within current debates about disciplinarity and academic disciplines.

Chiral battery, scaling laws and magnetic fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anand, Sampurn; Bhatt, Jitesh R.; Pandey, Arun Kumar, E-mail: sampurn@prl.res.in, E-mail: jeet@prl.res.in, E-mail: arunp@prl.res.in

2017-07-01

We study the generation and evolution of magnetic field in the presence of chiral imbalance and gravitational anomaly which gives an additional contribution to the vortical current. The contribution due to gravitational anomaly is proportional to T {sup 2} which can generate seed magnetic field irrespective of plasma being chirally charged or neutral. We estimate the order of magnitude of the magnetic field to be 10{sup 30} G at T ∼ 10{sup 9} GeV, with a typical length scale of the order of 10{sup −18} cm, which is much smaller than the Hubble radius at that temperature (10{sup −8} cm).more » Moreover, such a system possess scaling symmetry. We show that the T {sup 2} term in the vorticity current along with scaling symmetry leads to more power transfer from lower to higher length scale as compared to only chiral anomaly without scaling symmetry.« less

[Adult mother-daughter relationships and psychological well-being: attachment to mothers, depressive symptoms, and self-esteem].

PubMed

Kitamura, Kotomi

2008-06-01

This study examined how daughter's reported quality of their mother-daughter relationships during childhood and adulthood is related to their psychological well-being (depressive symptoms and self-esteem). A cross-sectional sample of 363 women, age 26 to 35 years, completed questionnaires. The association between the quality of daughters' relationships with their mothers and their psychological well-being depended on the daughters' marital and parental status. Regression estimates suggested that among single daughters and married daughters with children, childhood attachment dimensions (avoidance and anxiety) significantly contributed to psychological well-being, even after controlling for the effects of current closeness and excessive dependence. Current closeness, and excessive care seeking and care giving to their mother contributed to the psychological well-being of single daughters and married daughters without children, even after controlling for the effects of childhood attachment.

Plant Metabolomics: An Indispensable System Biology Tool for Plant Science.

PubMed

Hong, Jun; Yang, Litao; Zhang, Dabing; Shi, Jianxin

2016-06-01

As genomes of many plant species have been sequenced, demand for functional genomics has dramatically accelerated the improvement of other omics including metabolomics. Despite a large amount of metabolites still remaining to be identified, metabolomics has contributed significantly not only to the understanding of plant physiology and biology from the view of small chemical molecules that reflect the end point of biological activities, but also in past decades to the attempts to improve plant behavior under both normal and stressed conditions. Hereby, we summarize the current knowledge on the genetic and biochemical mechanisms underlying plant growth, development, and stress responses, focusing further on the contributions of metabolomics to practical applications in crop quality improvement and food safety assessment, as well as plant metabolic engineering. We also highlight the current challenges and future perspectives in this inspiring area, with the aim to stimulate further studies leading to better crop improvement of yield and quality.

Chronic neuropathologies of single and repetitive TBI: substrates of dementia?

PubMed Central

Smith, Douglas H.; Johnson, Victoria E.; Stewart, William

2014-01-01

Traumatic brain injury (TBI) has long been recognized to be a risk factor for dementia. This association has, however, only recently gained widespread attention through the increased awareness of ‘chronic traumatic encephalopathy’ (CTE) in athletes exposed to repetitive head injury. Originally termed ‘dementia pugilistica’ and linked to a career in boxing, descriptions of the neuropathological features of CTE include brain atrophy, cavum septum pellucidum, and amyloid-β, tau and TDP-43 pathologies, many of which might contribute to clinical syndromes of cognitive impairment. Similar chronic pathologies are also commonly found years after just a single moderate to severe TBI. However, little consensus currently exists on specific features of these post-TBI syndromes that might permit their confident clinical and/or pathological diagnosis. Moreover, the mechanisms contributing to neurodegeneration following TBI largely remain unknown. Here, we review the current literature and controversies in the study of chronic neuropathological changes after TBI. PMID:23458973

Report of survey results for newly licensed registered nurses in Washington state.

PubMed

Hirsch, Anne M

2011-10-01

Current projections for the need for nurses in Washington state are based on an increase in the need for health care, the aging of the population, and the inability of the nursing educational institutions to supply adequate numbers of graduates. Yet many new graduates are providing anecdotal evidence that they cannot find a job in nursing. This study gathered information regarding the employment of newly licensed registered nurses in Washington between May 2009 and August 2010. Questionnaires were administered to a randomly selected sample of 2,200 newly licensed nurses; 532 responses were returned. Nearly 81% reported current employment as a registered nurse and 69.5% reported that they were very or somewhat satisfied with their employment situation. The job search strategies, type of job sought, and factors contributing to their success are reported. Factors contributing to the success of their job search and to job dissatisfaction are explored. Copyright 2011, SLACK Incorporated.

Sound management may sequester methane in grazed rangeland ecosystems

PubMed Central

Wang, Chengjie; Han, Guodong; Wang, Shiping; Zhai, Xiajie; Brown, Joel; Havstad, Kris M.; Ma, Xiuzhi; Wilkes, Andreas; Zhao, Mengli; Tang, Shiming; Zhou, Pei; Jiang, Yuanyuan; Lu, Tingting; Wang, Zhongwu; Li, Zhiguo

2014-01-01

Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implemented in the main rangeland regions of China. The influences of rangeland improvement, utilization and livestock production on CH4 flux/emission were assessed to estimate CH4 reduction potential. Results indicate that the grazed rangeland ecosystem is currently a net source of atmospheric CH4. However, there is potential to convert the ecosystem to a net sink by improving management practices. Previous assessments of capacity for CH4 uptake in grazed rangeland ecosystems have not considered improved livestock management practices and thus underestimated potential for CH4 uptake. Optimal fertilization, rest and light grazing, and intensification of livestock management contribute mitigation potential significantly. PMID:24658176

Sound management may sequester methane in grazed rangeland ecosystems.

PubMed

Wang, Chengjie; Han, Guodong; Wang, Shiping; Zhai, Xiajie; Brown, Joel; Havstad, Kris M; Ma, Xiuzhi; Wilkes, Andreas; Zhao, Mengli; Tang, Shiming; Zhou, Pei; Jiang, Yuanyuan; Lu, Tingting; Wang, Zhongwu; Li, Zhiguo

2014-03-24

Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implemented in the main rangeland regions of China. The influences of rangeland improvement, utilization and livestock production on CH4 flux/emission were assessed to estimate CH4 reduction potential. Results indicate that the grazed rangeland ecosystem is currently a net source of atmospheric CH4. However, there is potential to convert the ecosystem to a net sink by improving management practices. Previous assessments of capacity for CH4 uptake in grazed rangeland ecosystems have not considered improved livestock management practices and thus underestimated potential for CH4 uptake. Optimal fertilization, rest and light grazing, and intensification of livestock management contribute mitigation potential significantly.

Bilirubin Modulates Acetylcholine Receptors In Rat Superior Cervical Ganglionic Neurons In a Bidirectional Manner

PubMed Central

Zhang, Chengmi; Wang, Zhenmeng; Dong, Jing; Pan, Ruirui; Qiu, Haibo; Zhang, Jinmin; Zhang, Peng; Zheng, Jijian; Yu, Weifeng

2014-01-01

Autonomic dysfunction as a partial contributing factor to cardiovascular instability in jaundiced patients is often associated with increased serum bilirubin levels. Whether increased serum bilirubin levels could directly inhibit sympathetic ganglion transmission by blocking neuronal nicotinic acetylcholine receptors (nAChRs) remains to be elucidated. Conventional patch-clamp recordings were used to study the effect of bilirubin on nAChRs currents from enzymatically dissociated rat superior cervical ganglia (SCG) neurons. The results showed that low concnetrations (0.5 and 2 μM) of bilirubin enhanced the peak ACh-evoked currents, while high concentrations (3 to 5.5 µM) of bilirubin suppressed the currents with an IC50 of 4 ± 0.5 μM. In addition, bilirubin decreased the extent of desensitization of nAChRs in a concentration-dependent manner. This inhibitory effect of bilirubin on nAChRs channel currents was non-competitive and voltage independent. Bilirubin partly improved the inhibitory effect of forskolin on ACh-induced currents without affecting the action of H-89. These data suggest that the dual effects of enhancement and suppression of bilirubin on nAChR function may be ascribed to the action mechanism of positive allosteric modulation and direct blockade. Thus, suppression of sympathetic ganglionic transmission through postganglionic nAChRs inhibition may partially contribute to the adverse cardiovascular effects in jaundiced patients. PMID:25503810

Research And Development Contributions to Aviation Progress (RADCAP): Executive summary

NASA Technical Reports Server (NTRS)

1972-01-01

Positive contributions of military aeronautical research and development programs to civil aviation are reviewed and some possible future contributions of those military programs are assessed. A summary is presented of detailed results concerned with: (1) review of the progress that has been made in aviation since 1925 and the significant technological advances that have been made; (2) an examination of current and planned military aeronautical research and technology programs and an assessment of their relevancy to the aeronautical R and D needs of civil aviation; (3) the relationship of the development base generated by military programs to the needs of civil airliner design, development, and production; (4) information on aeronautical R and D funding; and (5) the findings and observations of the RADCAP study.

Exploding the Myths: Caregiving in America. A Study by the Subcommittee on Human Services of the Select Committee on Aging. House of Representatives, Second Session.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Select Committee on Aging.

The purpose of this Congressional study is to underscore the continuing contribution of the family in providing care to the frail and disabled elderly. This study has been developed to distill information that currently exists, to provide new data based on national estimates and to highlight both public and private sector initiatives targeted at…

Potassium Currents of Olfactory Bulb Juxtaglomerular Cells: Characterization, Simulation, and Implications for Plateau Potential Firing

PubMed Central

Masurkar, Arjun V.; Chen, Wei R.

2011-01-01

Odor identity is encoded by the activity of olfactory bulb glomeruli, which receive primary sensory input and transfer it to projection neurons. Juxtaglomerular cells (JGCs) may influence glomerular processing via firing of long lasting plateau potentials. Though inward currents have been investigated, little is known regarding potassium current contribution to JGC plateau potentials. We pursued study of these currents, with the overarching goal of creating components for a computational model of JGC plateau potential firing. In conditions minimizing calcium-activated potassium current (IK(Ca)), we used whole cell voltage clamp and in vitro slice preparations to characterize three potassium currents in rat JGCs. The prominent component Ikt1 displayed rapid kinetics (τ10%−90% rise 0.6–2ms, τinactivation 5–10ms) and was blocked by high concentration 4-AP (5mM) and TEA (40mM). It had half maximal activation at −10mV (V½max) and little inactivation at rest. Ikt2, with slower kinetics (τ10%−90% rise 11–15ms, τinactivation 100–300ms), was blocked by low concentration 4-AP (0.5mM) and TEA (5mM). The V½max was 0mV and inactivation was also minimal at rest. Sustained current Ikt3 showed sensitivity to low concentration 4-AP and TEA, and had V½max of +10mV. Further experiments, in conditions of physiologic calcium buffering, suggested that IK(Ca) contributed to Ikt3 with minimal effect on plateau potential evolution. We transformed these characterizations into Hodgkin-Huxley models that robustly mimicked experimental data. Further simulation demonstrated that Ikt1 would be most efficiently activated by plateau potential waveforms, predicting a critical role in shaping JGC firing. These studies demonstrated that JGCs possess a unique potassium current profile, with delayed rectifier (Ikt3), atypical A-current (Ikt1), and D-current (Ikt2) in accordance with known expression patterns in OB glomeruli. Our simulations also provide an initial framework for more integrative models of JGC plateau potential firing. PMID:21704678

A systematic review on definitions and assessments of psychotic-like experiences.

PubMed

Lee, Kit-Wai; Chan, Kit-Wa; Chang, Wing-Chung; Lee, Edwin Ho-Ming; Hui, Christy Lai-Ming; Chen, Eric Yu-Hai

2016-02-01

Psychotic-like experiences (PLEs) or subclinical psychotic experiences have received increased attention as some studies have suggested continuity between PLEs and psychotic disorders. However, epidemiological and correlational studies of PLEs showed mixed findings - it is observed that different studies use a wide variety of definitions of PLEs, as well as different assessment tools that are designed to capture such described experiences. The differences in definitions and assessment tools adopted could contribute to the discrepancy of findings. The current review aims to examine the definitions and assessment tools adopted in the studies of PLEs. Literature search was conducted between October 2013 and February 2014 using three search engines: Medline, Web of Science and PubMed. A total of 76 papers met the selection criteria and were included in the current review. It is found that the majority of papers reviewed defined PLEs quantitatively using assessment tools and do not have a specific phenomenological definition, whereas assessment tools adopted have a wide variety. Furthermore, phenomenological studies of PLEs were rare. The variations in definitions and assessment tools of PLEs might contribute to mixed findings in researches. Reaching to a consensus through the study of phenomenology of PLEs is essential to further advancement of the research in this area. © 2015 Wiley Publishing Asia Pty Ltd.

Phenomenological aspects of the cognitive rumination construct.

PubMed

Meyer, Leonardo Fernandez; Taborda, José Geraldo Vernet; da Costa, Fábio Antônio; Soares, Ana Luiza Alfaya Galego; Mecler, Kátia; Valença, Alexandre Martins

2015-01-01

To evaluate the importance of phenomenological aspects of the cognitive rumination (CR) construct in current empirical psychiatric research. We searched SciELO, Scopus, ScienceDirect, MEDLINE, OneFile (GALE), SpringerLink, Cambridge Journals and Web of Science between February and March of 2014 for studies whose title and topic included the following keywords: cognitive rumination; rumination response scale; and self-reflection. The inclusion criteria were: empirical clinical study; CR as the main object of investigation; and study that included a conceptual definition of CR. The studies selected were published in English in biomedical journals in the last 10 years. Our phenomenological analysis was based on Karl Jaspers' General Psychopathology. Most current empirical studies adopt phenomenological cognitive elements in conceptual definitions. However, these elements do not seem to be carefully examined and are indistinctly understood as objective empirical factors that may be measured, which may contribute to misunderstandings about CR, erroneous interpretations of results and problematic theoretical models. Empirical studies fail when evaluating phenomenological aspects of the cognitive elements of the CR construct. Psychopathology and phenomenology may help define the characteristics of CR elements and may contribute to their understanding and hierarchical organization as a construct. A review of the psychopathology principles established by Jasper may clarify some of these issues.

Pre-service science teachers' perceptions of mathematics courses in a science teacher education programme

NASA Astrophysics Data System (ADS)

Incikabi, Lutfi; Serin, Mehmet Koray

2017-08-01

Most science departments offer compulsory mathematics courses to their students with the expectation that students can apply their experience from the mathematics courses to other fields of study, including science. The current study first aims to investigate the views of pre-service science teachers of science-teaching preparation degrees and their expectations regarding the difficulty level of mathematics courses in science-teaching education programmes. Second, the study investigates changes and the reasons behind the changes in their interest regarding mathematics after completing these courses. Third, the current study seeks to reveal undergraduate science teachers' opinions regarding the contribution of undergraduate mathematics courses to their professional development. Being qualitative in nature, this study was a case study. According to the results, almost all of the students considered that undergraduate mathematics courses were 'difficult' because of the complex and intensive content of the courses and their poor background mathematical knowledge. Moreover, the majority of science undergraduates mentioned that mathematics would contribute to their professional development as a science teacher. On the other hand, they declared a negative change in their attitude towards mathematics after completing the mathematics courses due to continuous failure at mathematics and their teachers' lack of knowledge in terms of teaching mathematics.

Current challenges in distinguishing climatic and anthropogenic contributions to alpine grassland variation on the Tibetan Plateau.

PubMed

Li, Lanhui; Zhang, Yili; Liu, Linshan; Wu, Jianshuang; Li, Shicheng; Zhang, Haiyan; Zhang, Binghua; Ding, Mingjun; Wang, Zhaofeng; Paudel, Basanta

2018-06-01

Quantifying the impact of climate change and human activities on grassland dynamics is an essential step for developing sustainable grassland ecosystem management strategies. However, the direction and magnitude of climate change and human activities in driving alpine grassland dynamic over the Tibetan Plateau remain under debates. Here, we systematically reviewed the relevant studies on the methods, main conclusions, and causes for the inconsistency in distinguishing the respective contribution of climatic and anthropogenic forces to alpine grassland dynamic. Both manipulative experiments and traditional statistical analysis show that climate warming increase biomass in alpine meadows and decrease in alpine steppes, while both alpine steppes and meadows benefit from an increase in precipitation or soil moisture. Overgrazing is a major factor for the degradation of alpine grassland in local areas with high level of human activity intensity. However, across the entire Tibetan Plateau and its subregions, four views characterize the remaining controversies: alpine grassland changes are primarily due to (1) climatic force, (2) nonclimatic force, (3) combination of anthropogenic and climatic force, or (4) alternation of anthropogenic and climatic force. Furthermore, these views also show spatial inconsistencies. Differences on the source and quality of remote sensing products, the structure and parameter of models, and overlooking the spatiotemporal heterogeneity of human activity intensity contribute to current disagreements. In this review, we highlight the necessity for taking the spatiotemporal heterogeneity of human activity intensity into account in the models of attribution assessment, and the importance for accurate validation of climatic and anthropogenic contribution to alpine grassland variation at multiple scales for future studies.

Theoretical analysis and simulations of strong terahertz radiation from the interaction of ultrashort laser pulses with gases

NASA Astrophysics Data System (ADS)

Chen, Min; Pukhov, Alexander; Peng, Xiao-Yu; Willi, Oswald

2008-10-01

Terahertz (THz) radiation from the interaction of ultrashort laser pulses with gases is studied both by theoretical analysis and particle-in-cell (PIC) simulations. A one-dimensional THz generation model based on the transient ionization electric current mechanism is given, which explains the results of one-dimensional PIC simulations. At the same time the relation between the final THz field and the initial transient ionization current is shown. One- and two-dimensional simulations show that for the THz generation the contribution of the electric current due to ionization is much larger than the one driven by the usual ponderomotive force. Ionization current generated by different laser pulses and gases is also studied numerically. Based on the numerical results we explain the scaling laws for THz emission observed in the recent experiments performed by Xie [Phys. Rev. Lett. 96, 075005 (2006)]. We also study the effective parameter region for the carrier envelop phase measurement by the use of THz generation.

Theoretical analysis and simulations of strong terahertz radiation from the interaction of ultrashort laser pulses with gases.

PubMed

Chen, Min; Pukhov, Alexander; Peng, Xiao-Yu; Willi, Oswald

2008-10-01

Terahertz (THz) radiation from the interaction of ultrashort laser pulses with gases is studied both by theoretical analysis and particle-in-cell (PIC) simulations. A one-dimensional THz generation model based on the transient ionization electric current mechanism is given, which explains the results of one-dimensional PIC simulations. At the same time the relation between the final THz field and the initial transient ionization current is shown. One- and two-dimensional simulations show that for the THz generation the contribution of the electric current due to ionization is much larger than the one driven by the usual ponderomotive force. Ionization current generated by different laser pulses and gases is also studied numerically. Based on the numerical results we explain the scaling laws for THz emission observed in the recent experiments performed by Xie et al. [Phys. Rev. Lett. 96, 075005 (2006)]. We also study the effective parameter region for the carrier envelop phase measurement by the use of THz generation.

Using Hierarchical Linear Modeling to Examine How Individual SLPs Differentially Contribute to Children's Language and Literacy Gains in Public Schools.

PubMed

Farquharson, Kelly; Tambyraja, Sherine R; Logan, Jessica; Justice, Laura M; Schmitt, Mary Beth

2015-08-01

The purpose of this study was twofold: (a) to determine the unique contributions in children's language and literacy gains, over 1 academic year, that are attributable to the individual speech-language pathologist (SLP) and (b) to explore possible child- and SLP-level factors that may further explain SLPs' contributions to children's language and literacy gains. Participants were 288 kindergarten and 1st-grade children with language impairment who were currently receiving school-based language intervention from SLPs. Using hierarchical linear modeling, we partitioned the variance in children's gains in language (i.e., grammar, vocabulary) and literacy (i.e., word decoding) that could be attributed to their individual SLP. Results revealed a significant contribution of individual SLPs to children's gains in grammar, vocabulary, and word decoding. Children's fall language scores and grade were significant predictors of SLPs' contributions, although no SLP-level predictors were significant. The present study makes a first step toward incorporating implementation science and suggests that, for children receiving school-based language intervention, variance in child language and literacy gains in an academic year is at least partially attributable to SLPs. Continued work in this area should examine the possible SLP-level characteristics that may further explicate the relative contributions of SLPs.

Polarization and Dielectric Study of Methylammonium Lead Iodide Thin Film to Reveal its Nonferroelectric Nature under Solar Cell Operating Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoque, Md Nadim Ferdous; Yang, Mengjin; Li, Zhen

2016-07-08

Researchers have debated whether methylammonium lead iodide (MAPbI3), with a perovskite crystal structure, is ferroelectric and therefore contributes to the current--voltage hysteresis commonly observed in hybrid perovskite solar cells (PSCs). We thoroughly investigated temperature-dependent polarization, dielectric, and impedance spectroscopies, and we found no evidence of ferroelectric effect in a MAPbI3 thin film at normal operating conditions. Therefore, the effect does not contribute to the hysteresis in PSCs, whereas the large component of ionic migration observed may play a critical role. Our temperature-based polarization and dielectric studies find that MAPbI3 exhibits different electrical behaviors below and above ca. 45 degrees C,more » suggesting a phase transition around this temperature. In particular, we report the activation energies of ionic migration for the two phases and temperature-dependent permittivity of MAPbI3. This study contributes to the understanding of the material properties and device performance of hybrid perovskites.« less

A tank-to-wheel analysis tool for energy and emissions studies in road vehicles.

PubMed

Silva, C M; Gonçalves, G A; Farias, T L; Mendes-Lopes, J M C

2006-08-15

Currently, oil based fuels are the primary energy source of road transport. The growing need for oil independence and CO(2) mitigation has lead to the increasing importance of alternative fuel usage. CO(2) is produced not only as the fuel is used in the vehicle (tank-to-wheel contribution), but also upstream, from the fuel extraction to the refueling station (well-to-tank contribution), and the life cycle of the fuel production (well-to-wheel contribution) must be considered in order to analyse the global impact of the fuel utilization. A road vehicle tank-to-wheel analysis tool that may be integrated with well-to-tank models was developed in the present study. The integration in a demonstration case study allowed to perform a life cycle assessment concerning the utilization of diesel and natural gas fuels in a specific network line of a bus transit company operating in the city of Porto, Portugal.

Configural face processing impacts race disparities in humanization and trust

PubMed Central

Cassidy, Brittany S.; Krendl, Anne C.; Stanko, Kathleen A.; Rydell, Robert J.; Young, Steven G.; Hugenberg, Kurt

2018-01-01

The dehumanization of Black Americans is an ongoing societal problem. Reducing configural face processing, a well-studied aspect of typical face encoding, decreases the activation of human-related concepts to White faces, suggesting that the extent that faces are configurally processed contributes to dehumanization. Because Black individuals are more dehumanized relative to White individuals, the current work examined how configural processing might contribute to their greater dehumanization. Study 1 showed that inverting faces (which reduces configural processing) reduced the activation of human-related concepts toward Black more than White faces. Studies 2a and 2b showed that reducing configural processing affects dehumanization by decreasing trust and increasing homogeneity among Black versus White faces. Studies 3a–d showed that configural processing effects emerge in racial outgroups for whom untrustworthiness may be a more salient group stereotype (i.e., Black, but not Asian, faces). Study 4 provided evidence that these effects are specific to reduced configural processing versus more general perceptual disfluency. Reduced configural processing may thus contribute to the greater dehumanization of Black relative to White individuals. PMID:29910510

Clockwork graviton contributions to muon g -2

NASA Astrophysics Data System (ADS)

Hong, Deog Ki; Kim, Du Hwan; Shin, Chang Sub

2018-02-01

The clockwork mechanism for gravity introduces a tower of massive graviton modes, clockwork gravitons, with a very compressed mass spectrum, whose interaction strengths are much stronger than those of massless gravitons. In this work, we compute the lowest order contributions of the clockwork gravitons to the anomalous magnetic moment, g -2 , of muon in the context of an extra dimensional model with a five-dimensional Planck mass, M5. We find that the total contributions are rather insensitive to the detailed model parameters and are determined mostly by the value of M5. To account for the current muon g -2 anomaly, M5 should be around 0.2 TeV, and the size of the extra dimension has to be quite large, l5≳10-7 m . For M5≳1 TeV , the clockwork graviton contributions are too small to explain the current muon g -2 anomaly. We also compare the clockwork graviton contributions with other extra dimensional models such as Randall-Sundrum models or large extra dimensional models. We find that the leading contributions in the small curvature limit are universal, but the cutoff-independent subleading contributions vary for different background geometries and the clockwork geometry gives the smallest subleading contributions.

Not planning a sustainable transport system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finnveden, Göran, E-mail: goran.finnveden@abe.kth.se; Åkerman, Jonas

2014-04-01

The overall objective of the Swedish transport policy is to ensure the economically efficient and sustainable provision of transport services for people and business throughout the country. More specifically, the transport sector shall, among other things, contribute to the achievement of environmental quality objectives in which the development of the transport system plays an important role in the achievement of the objectives. The aim of this study is to analyse if current transport planning supports this policy. This is done by analysing two recent cases: the National Infrastructure Plan 2010–2021, and the planning of Bypass Stockholm, a major road investment.more » Our results show that the plans are in conflict with several of the environmental quality objectives. Another interesting aspect of the planning processes is that the long-term climate goals are not included in the planning processes, neither as a clear goal nor as factor that will influence future transport systems. In this way, the long-term sustainability aspects are not present in the planning. We conclude that the two cases do not contribute to a sustainable transport system. Thus, several changes must be made in the processes, including putting up clear targets for emissions. Also, the methodology for the environmental assessments needs to be further developed and discussed. - Highlights: • Two cases are studied to analyse if current planning supports a sustainable transport system. • Results show that the plans are in conflict with several of the environmental quality objectives. • Long-term climate goals are not included in the planning processes. • Current practices do not contribute to a sustainable planning processes. • Methodology and process for environmental assessments must be further developed and discussed.« less

Block of voltage-gated potassium channels by Pacific ciguatoxin-1 contributes to increased neuronal excitability in rat sensory neurons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Birinyi-Strachan, Liesl C.; Gunning, Simon J.; Lewis, Richard J.

2005-04-15

The present study investigated the actions of the polyether marine toxin Pacific ciguatoxin-1 (P-CTX-1) on neuronal excitability in rat dorsal root ganglion (DRG) neurons using patch-clamp recording techniques. Under current-clamp conditions, bath application of 2-20 nM P-CTX-1 caused a rapid, concentration-dependent depolarization of the resting membrane potential in neurons expressing tetrodotoxin (TTX)-sensitive voltage-gated sodium (Na{sub v}) channels. This action was completely suppressed by the addition of 200 nM TTX to the external solution, indicating that this effect was mediated through TTX-sensitive Na{sub v} channels. In addition, P-CTX-1 also prolonged action potential and afterhyperpolarization (AHP) duration. In a subpopulation of neurons,more » P-CTX-1 also produced tonic action potential firing, an effect that was not accompanied by significant oscillation of the resting membrane potential. Conversely, in neurons expressing TTX-resistant Na{sub v} currents, P-CTX-1 failed to alter any parameter of neuronal excitability examined in this study. Under voltage-clamp conditions in rat DRG neurons, P-CTX-1 inhibited both delayed-rectifier and 'A-type' potassium currents in a dose-dependent manner, actions that occurred in the absence of alterations to the voltage dependence of activation. These actions appear to underlie the prolongation of the action potential and AHP, and contribute to repetitive firing. These data indicate that a block of potassium channels contributes to the increase in neuronal excitability, associated with a modulation of Na{sub v} channel gating, observed clinically in response to ciguatera poisoning.« less

Emission of atmospherically significant halocarbons by naturally occurring and farmed tropical macroalgae

NASA Astrophysics Data System (ADS)

Leedham, E. C.; Hughes, C.; Keng, F. S. L.; Phang, S.-M.; Malin, G.; Sturges, W. T.

2013-06-01

Current estimates of global halocarbon emissions highlight the tropical coastal environment as an important source of very short-lived (VSL) biogenic halocarbons to the troposphere and stratosphere, due to a combination of assumed high primary productivity in tropical coastal waters and the prevalence of deep convective transport, potentially capable of rapidly lifting surface emissions to the upper troposphere/lower stratosphere. However, despite this perceived importance, direct measurements of tropical coastal biogenic halocarbon emissions, notably from macroalgae (seaweeds), have not been made. In light of this, we provide the first dedicated study of halocarbon production by a range of 15 common tropical macroalgal species and compare these results to those from previous studies of polar and temperate macroalgae. Variation between species was substantial; CHBr3 production rates, measured at the end of a 24 h incubation, varied from 1.4 to 1129 pmol g FW-1 h-1 (FW = fresh weight of sample). We used our laboratory-determined emission rates to estimate emissions of CHBr3 and CH2Br2 (the two dominant VSL precursors of stratospheric bromine) from the coastlines of Malaysia and elsewhere in South East Asia (SEA). We compare these values to previous top-down model estimates of emissions from these regions and, by using several emission scenarios, we calculate an annual CHBr3 emission of 40 (6-224 Mmol Br-1 yr), a value that is lower than previous estimates. The contribution of tropical aquaculture to current emission budgets is also considered. Whilst the current aquaculture contribution to halocarbon emissions in this regional is small, the potential exists for substantial increases in aquaculture to make a significant contribution to regional halocarbon budgets.

Dissection of K+ currents in Caenorhabditis elegans muscle cells by genetics and RNA interference

PubMed Central

Santi, C. M.; Yuan, A.; Fawcett, G.; Wang, Z.-W.; Butler, A.; Nonet, M. L.; Wei, A.; Rojas, P.; Salkoff, L.

2003-01-01

GFP-promoter experiments have previously shown that at least nine genes encoding potassium channel subunits are expressed in Caenorhabditis elegans muscle. By using genetic, RNA interference, and physiological techniques we revealed the molecular identity of the major components of the outward K+ currents in body wall muscle cells in culture. We found that under physiological conditions, outward current is dominated by the products of only two genes, Shaker (Kv1) and Shal (Kv4), both expressing voltage-dependent potassium channels. Other channels may be held in reserve to respond to particular circumstances. Because GFP-promoter experiments indicated that slo-2 expression is prominent, we created a deletion mutant to identify the SLO-2 current in vivo. In both whole-cell and single-channel modes, in vivo SLO-2 channels were active only when intracellular Ca2+ and Cl- were raised above normal physiological conditions, as occurs during hypoxia. Under such conditions, SLO-2 is the largest outward current, contributing up to 87% of the total current. Other channels are present in muscle, but our results suggest that they are unlikely to contribute a large outward component under physiological conditions. However, they, too, may contribute currents conditional on other factors. Hence, the picture that emerges is of a complex membrane with a small number of household conductances functioning under normal circumstances, but with additional conductances that are activated during unusual circumstances. PMID:14612577

How do different components of Effortful Control contribute to children's mathematics achievement?

PubMed

Sánchez-Pérez, Noelia; Fuentes, Luis J; Pina, Violeta; López-López, Jose A; González-Salinas, Carmen

2015-01-01

This work sought to investigate the specific contribution of two different components of Effortful Control (EC) -attentional focusing (AF) and inhibitory control- to children's mathematics achievement. The sample was composed of 142 children aged 9-12 year-old. EC components were measured through the Temperament in Middle Childhood Questionnaire (TMCQ; parent's report); math achievement was measured via teacher's report and through the standard Woodcock-Johnson test. Additionally, the contribution of other cognitive and socio-emotional processes was taken into account. Our results showed that only AF significantly contributed to the variance of children's mathematics achievement; interestingly, mediational models showed that the relationship between effortful attentional self-regulation and mathematics achievement was mediated by academic peer popularity, as well as by intelligence and study skills. Results are discussed in the light of the current theories on the role of children's self-regulation abilities in the context of school.

A quantity characterizing variation of observed magnetic twist in solar active regions

NASA Astrophysics Data System (ADS)

Gao, Yu

2018-03-01

An alternative parameter RJz is introduced as the ratio of one of two kinds of opposite-sign current to the total current and is used to investigate the relationship between this quantity and the hemispheric helicity sign rule (HSR) that has been established by a series of previous statistical studies. The classification of current in each hemisphere obeys the following rule: if the product of the current and the corresponding longitudinal field component contributes a consistent sign with respect to the HSR, it is called “HSR-compliant” current, otherwise it is called “HSR-noncompliant” current. Firstly, consistency between the butterfly diagram of RJz and current helicity was obtained in a statistical study. Active regions with RJz smaller than 0.5 tend to obey the HSR whereas those with RJz greater than 0.5 tend to disobey it. The “HSR-compliant” current systems have a 60% probability of realization compared to 40% for “HSR-noncompliant” current systems. Overall, the HSR is violated for active regions in which the “HSR-noncompliant” current is greater than the “HSR-compliant” current. Secondly, the parameter RJz was subsequently used to study the evolution of current systems in the case analyses of flare-productive active regions NOAA AR 11158 and AR 11283. It is found that there is a “RJz -quasi-stationary” phase that is relatively flare quiescent and “RJz -dynamic” phase that is characterized by the occurrence of large flares.

Current siRNA Targets in Atherosclerosis and Aortic Aneurysm

PubMed Central

Pradhan-Nabzdyk, Leena; Huang, Chenyu; Logerfo, Frank W.; Nabzdyk, Christoph S.

2014-01-01

Atherosclerosis (ATH) and aortic aneurysms (AA) remain challenging chronic diseases that confer high morbidity and mortality despite advances in medical, interventional, and surgical care. RNA interference represents a promising technology that may be utilized to silence genes contributing to ATH and AA. Despite positive results in preclinical and some clinical feasibility studies, challenges such as target/sequence validation, tissue specificity, transfection efficiency, and mitigation of unwanted off-target effects remain to be addressed. In this review the most current targets and some novel approaches in siRNA delivery are being discussed. Due to the plethora of investigated targets, only studies published between 2010 and 2014 were included. PMID:24882715

A Case Study on English Language Learners' Task-Based Interaction and Avatar Identities in Second Life: A Mixed-Methods Design

ERIC Educational Resources Information Center

Chen, Julian ChengChiang

2014-01-01

English as a foreign language (EFL) learners' language use in 3-D virtual environments is a vibrant avenue that still deserves more research attention in the field of CALL. To contribute research and pedagogical implications to the current Second Life (SL) literature, this study aims to examine EFL adult learners' use of communication strategies…

A View of the Neural Representation of Second Language Syntax through Artificial Language Learning under Implicit Contexts of Exposure

ERIC Educational Resources Information Center

Morgan-Short, Kara; Deng, ZhiZhou; Brill-Schuetz, Katherine A.; Faretta- Stutenberg, Mandy; Wong, Patrick C. M.; Wong, Francis C. K.

2015-01-01

The current study aims to make an initial neuroimaging contribution to central implicit-explicit issues in second language (L2) acquisition by considering how implicit and explicit contexts mediate the neural representation of L2. Focusing on implicit contexts, the study employs a longitudinal design to examine the neural representation of L2…

Perceived Learning and Students' Perceptions toward Using Tablets for Learning: The Mediating Role of Perceived Engagement among High School Students

ERIC Educational Resources Information Center

Soffer, Tal; Yaron, Efrat

2017-01-01

Integrating mobile technology in schools has become a growing trend in recent years. Studies suggest that the use of tablets has potential contributions for learning. The current study explored the use of tablets for learning among 427 high school students, utilizing both qualitative and quantitative methods. The purpose was to assess students'…

Using iPad-Based Mobile Learning to Teach Creative Engineering within a Problem-Based Learning Pedagogy

ERIC Educational Resources Information Center

Li, Yulong; Wang, Lixun

2018-01-01

This case study, noting the increasing interest in iPad-based mobile learning research and aware of the current dearth of engineering talent in the UK, aims to contribute to a still sparse area of research that links iPad use to engineering education. To achieve this, the study investigates the integration of iPad-based mobile learning…

"Wow, I Get to Choose Now!" Bilingualism and Biliteracy Development from Childhood to Young Adulthood

ERIC Educational Resources Information Center

Worthy, Jo; Nuñez, Idalia; Espinoza, Katherine

2016-01-01

Much research has focused on the reasons and mechanisms for immigrant language loss. However, there is a scarcity of research about influences on language maintenance over time, and much of this work employs survey data. With the current study, we aim to contribute to this body of research with a qualitative study of a bilingual individual,…

Bridging Theory and Practice: A Critical Discourse Analysis of a Social Justice Initiative within a Narrative Supervision Process

ERIC Educational Resources Information Center

Kahn, Sarah Zeta

2013-01-01

The purpose of this study was to increase the current understanding of what occurs within a narrative supervision process and to explore how this approach to supervision can contribute to the development of educational practices that promote social justice efforts in the field of marriage and family therapy. In particular, this study sought to…

The Adoption of On-Demand Learning in Organizations in the United States

ERIC Educational Resources Information Center

Cui, Lianbin

2010-01-01

There is a lack of studies on the current status of the use of on-demand learning in organizations and factors that may accelerate or hold back the acceptance and implementation of on-demand learning in organizations. The purpose of this study is to contribute to a better understanding of the adoption of on-demand learning in organizations in the…

Prevention of the Post-traumatic Fibrotic Response in Joints

DTIC Science & Technology

2014-10-01

an experimental model in mice. The American journal of forensic medicine and pathology . 1988; 9(4):310-2. 14 APPENDICES: An abstract...ongoing study addresses the critical clinical problem of posttraumatic joint stiffness, a pathology that reduces the range of motion (ROM) of injured...joints and contributes to the development of osteoarthritis. The fundamental hypothesis that drives the current study is that pathological fibrotic

Strategies and Attributes of Highly Productive Scholars and Contributors to the School Psychology Literature: Recommendations for Increasing Scholarly Productivity

ERIC Educational Resources Information Center

Martinez, Rebecca S.; Floyd, Randy G.; Erichsen, Luke W.

2011-01-01

In all academic fields, there are scholars who contribute to the research literature at exceptionally high levels. The goal of the current study was to discover what school psychology researchers with remarkably high levels of journal publication do to be so productive. In Study 1, 94 highly productive school psychology scholars were identified…

Alterations in Aspergillus brasiliensis (niger) ATCC 9642 membranes associated to metabolism modifications during application of low-intensity electric current.

PubMed

Velasco-Alvarez, Nancy; Gutiérrez-Rojas, Mariano; González, Ignacio

2017-12-01

The effects of electric current on membranes associated with metabolism modifications in Aspergillus brasiliensis (niger) ATCC 9642 were studied. A 450-mL electrochemical cell with titanium ruthenium-oxide coated electrodes and packed with 15g of perlite, as inert support, was inoculated with A. brasiliensis spores and incubated in a solid inert-substrate culture (12 d; 30°C). Then, 4.5days after starting the culture, a current of 0.42mAcm -2 was applied for 24h. The application of low-intensity electric current increased the molecular oxygen consumption rate in the mitochondrial respiratory chain, resulting in high concentrations of reactive oxygen species, promoting high lipoperoxidation levels, according to measured malondialdehyde, and consequent alterations in membrane permeability explained the high n-hexadecane (HXD) degradation rates observed here (4.7-fold higher than cultures without current). Finally, cell differentiation and spore production were strongly stimulated. The study contributes to the understanding of the effect of current on the cell membrane and its association with HXD metabolism. Copyright © 2017. Published by Elsevier B.V.

Author contributions to ecological publications: What does it mean to be an author in modern ecological research?

PubMed

Logan, John M; Bean, Sarah B; Myers, Andrew E

2017-01-01

Authorship is a central element of scientific research carrying a variety of rewards and responsibilities, and while various guidelines exist, actual author contributions are often ambiguous. Inconsistent or limited contributions threaten to devalue authorship as intellectual currency and diminish authors' responsibility for published content. Researchers have assessed author contributions in the medical literature and other research fields, but similar data for the field of ecological research are lacking. Authorship practices in ecological research are broadly representative of a variety of fields due to the cross-disciplinary nature of collaborations in ecological studies. To better understand author contributions to current research, we distributed a survey regarding co-author contributions to a random selection of 996 lead authors of manuscripts published in ecological journals in 2010. We obtained useable responses from 45% of surveyed authors. Reported lead author contributions in ecological research studies consistently included conception of the project idea, data collection, analysis, and writing. Middle and last author contributions instead showed a high level of individual variability. Lead authorship in ecology is well defined while secondary authorship is more ambiguous. Nearly half (48%) of all studies included in our survey had some level of non-compliance with Ecological Society of America (ESA) authorship guidelines and the majority of studies (78%) contained at least one co-author that did not meet International Committee of Medical Journal Editors (ICMJE) requirements. Incidence of non-compliance varied with lead author occupation and author position. The probability of a study including an author that was non-compliant with ESA guidelines was lowest for professor-led studies and highest for graduate student and post doctoral researcher-led studies. Among studies with > two co-authors, all lead authors met ESA guidelines and only 2% failed to meet ICMJE requirements. Middle (24% ESA, 63% ICMJE) and last (37% ESA, 60% ICMJE) authors had higher rates of non-compliance. The probability of a study containing a co-author that did not meet ESA or ICMJE requirements increased significantly with the number of co-authors per study although even studies with only two co-authors had a high probability of non-compliance of approximately 60% (ICMJE) and 15 to 40% (ESA). Given the variable and often limited contributions of authors in our survey and past studies of other research disciplines, institutions, journals, and scientific societies need to implement new approaches to instill meaning in authorship status. A byline approach may not alter author contributions but would better define individual contributions and reduce existing ambiguity regarding the meaning of authorship in modern ecological research.

Ionospheric magnetic signals during conjunctions between ground based and Swarm satellite observations

NASA Astrophysics Data System (ADS)

Saturnino, Diana; Olsen, Nils; Finlay, Chris

2017-04-01

High-precision magnetic measurements collected by satellites such as Swarm or CHAMP,flying at altitudes between 300 and 800km, allow for improved geomagnetic field modelling. An accurate description of the internal (core and crust) field must account for contributions from other sources, such as the ionosphere and magnetosphere. However, the description of the rapidly changing external field contributions, particularly during the quiet times from which the data are selected, constitutes a major challenge of the construction of such models. Our study attempts to obtain improved knowledge on ionospheric field contributions during quiet times conditions, in particular during night local times. We use two different datasets: ground magnetic observatories time series (obtained below the ionospheric E-layer currents), and Swarm satellites measurements acquired above these currents. First, we remove from the data estimates of the core, lithospheric and large-scale magnetospheric magnetic contributions as given by the CHAOS-6 model, to obtain corrected time series. Then, we focus on the differences of the corrected time series: for a pair of ground magnetic observatories, we determine the time series of the difference, and similarly we determine time series differences at satellite altitude, given by the difference between the Swarm Alpha and Charlie satellites taken in the vicinity of the ground observatory locations. The obtained differences time series are analysed regarding their temporal and spatial scales variations, with emphasis on measurements during night local times.

What socio-demographic factors influence poverty and financial health care access among disabled people in Flanders: a cross-sectional study

PubMed Central

2014-01-01

Background Current literature shows that people with a disability have a lower income than people without a disability. Disabled people often experience difficulties with health care access. The objective of this study is to assess the current financial situation and poverty rate amongst disabled people in Flanders. Furthermore we wanted to analyze factors that contribute to the risk of poverty and problems with financial health care access in adult people with a disability in Flanders. Methods An online and paper survey were constructed and made available through two large organizations for people with different types of disability in Flanders. Descriptive statistics and logistic regression analysis were performed. Results In this convenience sample, 20.9% of the 889 respondents live under the poverty threshold. Important contributing factors to the risk of poverty are having children (OR 3.43, 95% CI 2.10-5.59) and a low level of dependence (OR 16.40, 95% CI 6.21-43.28). 25.2% of the respondents did not access health care because of financial shortcomings. A low level of dependence is one important contributing factor (OR 3.16, 95% CI 1.41-6.98) to limited financial health care access. Conclusion This research confirms that disability is associated with a higher risk of poverty and impaired financial health care access. PMID:24521283

What socio-demographic factors influence poverty and financial health care access among disabled people in Flanders: a cross-sectional study.

PubMed

Adams, Margo; Augustyns, Nele; Janssens, Herman; Vriesacker, Bart; Van Hal, Guido

2014-02-12

Current literature shows that people with a disability have a lower income than people without a disability. Disabled people often experience difficulties with health care access.The objective of this study is to assess the current financial situation and poverty rate amongst disabled people in Flanders. Furthermore we wanted to analyze factors that contribute to the risk of poverty and problems with financial health care access in adult people with a disability in Flanders. An online and paper survey were constructed and made available through two large organizations for people with different types of disability in Flanders. Descriptive statistics and logistic regression analysis were performed. In this convenience sample, 20.9% of the 889 respondents live under the poverty threshold. Important contributing factors to the risk of poverty are having children (OR 3.43, 95% CI 2.10-5.59) and a low level of dependence (OR 16.40, 95% CI 6.21-43.28). 25.2% of the respondents did not access health care because of financial shortcomings. A low level of dependence is one important contributing factor (OR 3.16, 95% CI 1.41-6.98) to limited financial health care access. This research confirms that disability is associated with a higher risk of poverty and impaired financial health care access.

USE OF REAL-TIME LIGHT SCATTERING DATA TO ESTIMATE THE CONTRIBUTION OF INFILTRATED AND INDOOR-GENERATED PARTICLES TO INDOOR AIR

EPA Science Inventory

The contribution of outdoor particulate matter (PM) to residential indoor concentrations is currently not well understood. Most importantly, separating indoor PM into indoor- and outdoor-generated components will greatly enhance our knowledge of the outdoor contribution to tot...

Genetic composition of captive panda population.

PubMed

Yang, Jiandong; Shen, Fujun; Hou, Rong; Da, Yang

2016-10-03

A major function of the captive panda population is to preserve the genetic diversity of wild panda populations in their natural habitats. Understanding the genetic composition of the captive panda population in terms of genetic contributions from the wild panda populations provides necessary knowledge for breeding plans to preserve the genetic diversity of the wild panda populations. The genetic contributions from different wild populations to the captive panda population were highly unbalanced, with Qionglai accounting for 52.2 % of the captive panda gene pool, followed by Minshan with 21.5 %, Qinling with 10.6 %, Liangshan with 8.2 %, and Xiaoxiangling with 3.6 %, whereas Daxiangling, which had similar population size as Xiaoxiangling, had no genetic representation in the captive population. The current breeding recommendations may increase the contribution of some small wild populations at the expense of decreasing the contributions of other small wild populations, i.e., increasing the Xiaoxiangling contribution while decreasing the contribution of Liangshan, or sharply increasing the Qinling contribution while decreasing the contributions of Xiaoxiangling and Liangshan, which were two of the three smallest wild populations and were already severely under-represented in the captive population. We developed three habitat-controlled breeding plans that could increase the genetic contributions from the smallest wild populations to 6.7-11.2 % for Xiaoxiangling, 11.5-12.3 % for Liangshan and 12.9-20.0 % for Qinling among the offspring of one breeding season while reducing the risk of hidden inbreeding due to related founders from the same habitat undetectable by pedigree data. The three smallest wild panda populations of Daxiangling, Xiaoxiangling and Liangshan either had no representation or were severely unrepresented in the current captive panda population. By incorporating the breeding goal of increasing the genetic contributions from the smallest wild populations into breeding plans, the severely under-represented small wild populations in the current captive panda population could be increased steadily for the near future.

Orientation Perception in Williams Syndrome: Discrimination and Integration

ERIC Educational Resources Information Center

Palomares, Melanie; Landau, Barbara; Egeth, Howard

2009-01-01

Williams Syndrome (WS) is a rare neurodevelopmental disorder, which stems from a genetic deletion on chromosome 7 and causes a profound weakness in visuospatial cognition. Our current study explores how orientation perception may contribute to the visuospatial deficits in WS. In Experiment 1, we found that WS individuals and normal 3-4 year olds…

Understanding the Role of Representation in Interorganizational Knowledge Integration: A Case Study of an IT Outsourcing Project

ERIC Educational Resources Information Center

Werr, Andreas; Runsten, Philip

2013-01-01

Purpose: The current paper aims at contributing to the understanding of interorganizational knowledge integration by highlighting the role of individuals' understandings of the task and how they shape knowledge integrating behaviours. Design/methodology/approach: The paper presents a framework of knowledge integration as heedful interrelating.…

Design Matters: Explorations of Content and Design in Fraction Games

ERIC Educational Resources Information Center

Gresalfi, Melissa Sommerfeld; Rittle-Johnson, Bethany; Loehr, Abbey; Nichols, Isaac

2018-01-01

The goal of the current study was to contribute to our emergent understanding of whether and how particular types of digital games can support student learning and engagement. We focused on commercially available educational apps that focused on similar content (fraction comparison and equivalence) but represented extremes in how game-like they…

A Qualitative Understanding of Occupational Engagement in College Students

ERIC Educational Resources Information Center

Bjornsen, Abby L.

2011-01-01

The purpose of the current study is to examine the transition experiences of college students nearing graduation through the lens of occupational engagement. The construct of occupational engagement is defined as "...taking part in behaviors that contribute to the decision-maker's fund of information and experience of the larger world, not…

Psychological Sense of Community among Students on Religious Collegiate Campuses in the Christian Evangelical Tradition

ERIC Educational Resources Information Center

Bohus, Steve; Woods, Robert H., Jr.; Chan, K. Caleb

2005-01-01

The current study sought to identify factors which contribute to Psychological Sense of Community (PSC) among students on religious collegiate campuses within the Christian Evangelical tradition. The researchers examined responses from 596 undergraduate students at 11 Christian colleges and universities nationwide. The results support the…

Theorizing and Studying the Language-Teaching Mind: Mapping Research on Language Teacher Cognition

ERIC Educational Resources Information Center

Burns, Anne; Freeman, Donald; Edwards, Emily

2015-01-01

The overarching project of the conceptual and empirical contributions in this special issue is to redraw boundaries for language teacher cognition research. Our aim in this final article is to complement the foregoing collection of articles by conceptualizing ontologically and methodologically past and current trajectories in language teacher…

Joint Development of Teacher Cognition and Identity through Learning to Teach L2 Pronunciation

ERIC Educational Resources Information Center

Burri, Michael; Chen, Honglin; Baker, Amanda

2017-01-01

The constructs of teacher cognition and teacher identity have recently gained considerable attention in second language teacher education research for their crucial roles in understanding teacher learning. While a number of current studies have examined the contributions of both constructs, the connections between cognition and identity are yet to…

What to Do about Being Overwhelmed: Graduate Students, Stress and University Services

ERIC Educational Resources Information Center

Oswalt, Sara B.; Riddock, Christina C.

2007-01-01

Few studies have examined graduate students and stress. At a large, Southeastern university, 223 graduate students completed a survey about factors contributing their stress, current coping strategies and related university services. A majority felt stressed (48.9%) or very stressed (24.7%). There were significant differences in coping strategies…

Brain Activity during Performance of Naming Tasks: Comparison between Dyslexic and Regular Readers

ERIC Educational Resources Information Center

Breznitz, Zvia

2005-01-01

This research was aimed at contributing to the current understanding of the underlying factors of naming speed and the causes of naming speed deficits. Forty regular readers and 40 dyslexic university students participated in the study. Electrophysiological (Event-Related Potentials [ERPs]) and behavioral measures were employed. Behavioral…

Music Perception and Cognition in the First Year of Life.

ERIC Educational Resources Information Center

Ilari, Beatriz Senoi

2002-01-01

Reviews literature on music perception and cognition in the first year of life and examines their contribution to domains such as child development and music education. Focuses on studies examining musical features and the uses of music in the everyday life of infants and their caretakers. Critiques previous and current literature. Discusses…

Introductory Remarks: Points of Concern with Current Interpretations of the Effects of Early Malnutrition on Mental Development

ERIC Educational Resources Information Center

Barnes, R. H.

1972-01-01

Emphasizes that from a practical point of view, it is important that studies with malnourished children emphasize the interactions between nutrition and environment rather than attempt complex, costly experiments which hopefully will assess the contribution of each of the components alone. (Author/JM)

The Perceived Success of Tutoring Students with Learning Disabilities: Relations to Tutee and Tutoring Variables

ERIC Educational Resources Information Center

Michael, Rinat

2016-01-01

The current study examined the contribution of two types of variables to the perceived success of a tutoring project for college students with learning disabilities (LD): tutoring-related variables (the degree of engagement in different tutoring activities and difficulties encountered during tutoring), and tutee-related variables (learning…

Anticipated Work-Family Conflict: Effects of Role Salience and Self-Efficacy

ERIC Educational Resources Information Center

Cinamon, Rachel Gali

2010-01-01

The current study investigated how male and female university students' self-efficacy and their role salience contributed to the variance in their anticipated work-family conflict (WFC). Participants comprised 387 unmarried students (mean age 24 years). Cluster analysis yielded four profiles of participants who differed in their attributions of…

An Evolutionary Approach to Harnessing Complex Systems Thinking in the Science and Technology Classroom

ERIC Educational Resources Information Center

Yoon, Susan A.

2008-01-01

Educational efforts to incorporate ethical decision-making in science classrooms about current science and technology issues have met with great challenges. Some research suggests that the inherent complexity in both the subject matter content and the structure and dynamics of classrooms contribute to this challenge. This study seeks to…

Process and Post-Process: A Discursive History.

ERIC Educational Resources Information Center

Matsuda, Paul Kei

2003-01-01

Examines the history of process and post-process in composition studies, focusing on ways in which terms, such as "current-traditional rhetoric,""process," and "post-process" have contributed to the discursive construction of reality. Argues that use of the term post-process in the context of second language writing needs to be guided by a…

Literary Discussions and Advanced-Superior Speaking Functions in the Undergraduate Language Program

ERIC Educational Resources Information Center

Darhower, Mark

2014-01-01

During the last decade, researchers of foreign language pedagogy have become increasingly interested in the "language-literature divide" (Donato and Brooks 2004). The purpose of the current study is to contribute to this growing body of research by investigating the extent to which whole class discussions in three third-year…

Does Couple and Relationship Education Work for Individuals in Stepfamilies? A Meta-Analytic Study

ERIC Educational Resources Information Center

Lucier-Greer, Mallory; Adler-Baeder, Francesca

2012-01-01

Recent meta-analytic efforts have documented how couple and relationship education (CRE) programs promote healthy relationship and family functioning. The current meta-analysis contributes to this body of literature by examining stepfamily couples, an at-risk, subpopulation of participants, and assessing the effectiveness of CRE programs for…

Research on Automatic Classification, Indexing and Extracting. Annual Progress Report.

ERIC Educational Resources Information Center

Baker, F.T.; And Others

In order to contribute to the success of several studies for automatic classification, indexing and extracting currently in progress, as well as to further the theoretical and practical understanding of textual item distributions, the development of a frequency program capable of supplying these types of information was undertaken. The program…

Examining the Relationships among Item Recognition, Source Recognition, and Recall from an Individual Differences Perspective

ERIC Educational Resources Information Center

Unsworth, Nash; Brewer, Gene A.

2009-01-01

The authors of the current study examined the relationships among item-recognition, source-recognition, free recall, and other memory and cognitive ability tasks via an individual differences analysis. Two independent sources of variance contributed to item-recognition and source-recognition performance, and these two constructs related…

New Grandparents' Mental Health: The Protective Role of Optimism, Self-Mastery, and Social Support

ERIC Educational Resources Information Center

Ben Shlomo, Shirley; Taubman - Ben-Ari, Orit

2012-01-01

The current study examines the contribution of optimism, self-mastery, perceived social support, and background variables (age, physical health, economic status) to mental health following the transition to grandparenthood. The sample consisted of 257 first-time Israeli grandparents (grandmothers and grandfathers, maternal and paternal) who were…

How Dynamic Is Interhemispheric Interaction? Effects of Task Switching on the across-Hemisphere Advantage

ERIC Educational Resources Information Center

Welcome, Suzanne E.; Chiarello, Christine

2008-01-01

Interaction between the cerebral hemispheres may allow both hemispheres to contribute their processing resources in order to cope efficiently with complex tasks [Banich, M. (1998). The missing link: the role of interhemispheric interaction in attentional processing. "Brain and Cognition," 36, 128-157]. The current study investigated whether the…

Correlates of Parental Differential Treatment: Parental and Contextual Factors during Middle Childhood

ERIC Educational Resources Information Center

Atzaba-Poria, Naama; Pike, Alison

2008-01-01

The current study examined whether parental and contextual risk factors contribute to mothers' and fathers' differential treatment (MDT/FDT) when accounting for sibling dyad characteristics. Also explored was whether family type (single mothers vs. 2 parents) moderated the links between the parental and contextual correlates and MDT. One hundred…

The Joint Construction of Meaning in Writing Conferences

ERIC Educational Resources Information Center

Haneda, Mari

2004-01-01

Using an analytical framework that combines insights from a variety of previous studies, the current paper aims to contribute to the description of the joint construction of meaning in pedagogical discourse, in particular in one-on-one teacher-student interaction in writing conferences in a Japanese-as-a-foreign language (JFL) class. The argument…

Young People's and Parent's Perceptions of Managed Moves

ERIC Educational Resources Information Center

Bagley, Christopher; Hallam, Susan

2016-01-01

The current research aimed to increase understanding of the experiences of young people and their parents of managed moves, what contributed to success and the nature of the challenges experienced. The study was conducted in one English Local Authority, where five young people and their parents were interviewed. Five superordinate themes emerged…

Mind, Brain, and Literacy: Biomarkers as Usable Knowledge for Education

ERIC Educational Resources Information Center

Goswami, Usha

2009-01-01

Neuroscience has the potential to make some very exciting contributions to education and pedagogy. However, it is important to ask whether the insights from neuroscience studies can provide "usable knowledge" for educators. With respect to literacy, for example, current neuroimaging methods allow us to ask research questions about how the brain…

Comparative and International Education: Policy Transfer, Context Sensitivity and Professional Development

ERIC Educational Resources Information Center

Crossley, Michael; Watson, Keith

2009-01-01

This paper examines the intellectual and professional contribution of comparative and international studies to the field of education. It explores the nature of the challenges that are currently being faced, and assesses its potential for the advancement of future teaching, research and professional development. Attention is paid to the place of…

Brief Report: Faces Cause Less Distraction in Autism

ERIC Educational Resources Information Center

Riby, Deborah M.; Brown, Philippa H.; Jones, Nicola; Hanley, Mary

2012-01-01

Individuals with autism have difficulties interpreting face cues that contribute to deficits of social communication. When faces need to be processed for meaning they fail to capture and hold the attention of individuals with autism. In the current study we illustrate that faces fail to capture attention in a typical manner even when they are…

The Related Effects of Item Characteristics in Measures of Epistemological Beliefs

ERIC Educational Resources Information Center

Pope, Kathryn J.; Mooney, Gillian A.

2016-01-01

Personal epistemology is concerned with people's beliefs or assumptions about the nature of knowledge and knowing. Whilst contributions in this field can be traced back to the 1970s, fundamental questions about the ontology and epistemology of the construct still remain. The current study explored the effects of three characteristics of questions…

Student Interactions in Online Discussion Forum: Empirical Research from "Media Richness Theory" Perspective

ERIC Educational Resources Information Center

Balaji, M. S.; Chakrabarti, Diganta

2010-01-01

The present study contributes to the understanding of the effectiveness of online discussion forum in student learning. A conceptual model based on "theory of online learning" and "media richness theory" was proposed and empirically tested. We extend the current understanding of media richness theory to suggest that use of…

Peer Assessment of Group Members in Tertiary Contexts

ERIC Educational Resources Information Center

Kilickaya, Ferit

2017-01-01

The current chapter aimed at investigating language students' perceptions of peer assessment of the group members' contribution to group work. The research context of the study included the department of foreign language education at a state university in Burdur, Turkey. The participants were 35 students enrolled at the third-year class entitled…

Influences of Early English Language Teaching on Oral Fluency

ERIC Educational Resources Information Center

de Wolf, Stephana; Smit, Nienke; Lowie, Wander

2017-01-01

Elementary-level foreign language education is currently receiving a lot of attention in the literature on second language learning, and has emerged as an important educational policy issue. The present study aims to contribute to this discussion by focusing on the fluency benefits gained from early foreign language teaching. The participants were…

Anxiety Symptoms Account for the Link between Reactive Aggression and Sleep Problems among Latino Adolescents

ERIC Educational Resources Information Center

Fite, Paula J.; Becker, Stephen P.; Rubens, Sonia L.; Cheatham-Johnson, Randi

2015-01-01

Background: Sleep problems are common among adolescents and have a negative impact on functioning. A better understanding of factors that contribute to sleep problems in adolescence can help guide more effective, targeted interventions. Objective: The current study examined the associations between reactive and proactive functions of aggression…

The Contributions of Infant Temperament and Child Care to Infant Social Development

ERIC Educational Resources Information Center

Nathans, Laura L.; Meece, Darrell; Kossek, Ellen; Barratt, Marguerite

2004-01-01

Previous research has documented associations between young children's social development and both temperament and child care quality. The preponderance of research in this area has focused on preschool-age and older children, resulting in few studies focusing on these variables during infancy. In the current investigation, temperament and child…

A Challenge for Social Studies Educators: Increasing Civility in Schools and Society by Modeling Civic Virtues

ERIC Educational Resources Information Center

Moore, James

2012-01-01

Many scholars, teachers, parents, as well as others, are concerned with the decline of civility in public discourse and public schools. The sharp differences among various ideological groups, exacerbated by media incivility, are contributing factors to rising incivility. This ideological divide currently manifests itself in bitter partisan…

The Mental and Physical Health of Homeless Youth: A Literature Review

ERIC Educational Resources Information Center

Edidin, Jennifer P.; Ganim, Zoe; Hunter, Scott J.; Karnik, Niranjan S.

2012-01-01

Youth homelessness is a growing concern in the United States. Despite difficulties studying this population due to inconsistent definitions of what it means to be a youth and homeless, the current body of research indicates that abuse, family breakdown, and disruptive family relationships are common contributing factors to youth homelessness.…

The Contribution of Academics' Engagement in Research to Undergraduate Education

ERIC Educational Resources Information Center

Hajdarpasic, Ademir; Brew, Angela; Popenici, Stefan

2015-01-01

Can current trends to develop teaching-only academic positions be reconciled with the notion of the interrelationship of teaching and research as a defining characteristic of universities? In particular, what does academics' engagement in research add to students' learning? A study of 200 undergraduates' perceptions of the role of staff research…

Role of Resilient Personality on Lower Achieving First Grade Students' Current and Future Achievement

ERIC Educational Resources Information Center

Kwok, Oi-man; Hughes, Jan N.; Luo, Wen

2007-01-01

This study investigated a measurement model of personality resilience and the contribution of personality resilience to lower achieving first grade students' academic achievement. Participants were 445 ethnically diverse children who at entrance to first grade scored below their school district median on a test of literacy. Participants were…

Doing Race in Different Places: Black Racial Cohesion on Black and White College Campuses

ERIC Educational Resources Information Center

Bentley-Edwards, Keisha L.; Chapman-Hilliard, Collette

2015-01-01

Understanding the range of factors that contribute to Black students' success requires scholars to examine resiliency from multifaceted perspectives that include aspects of social competency, social responsibility, and agency. Using a national sample of 242 Black college students, the current study examines the indicators that inform racial…

Skills, Competencies and Gender: Issues for Pay and Training.

ERIC Educational Resources Information Center

Strebler, Marie; And Others

The extent to which skill and competency-based systems used by work organizations in the United Kingdom may contribute to maintenance of the pay gap between men and women was examined through a review of the following: pertinent literature from the United Kingdom and United States; 15 published case studies; current Institute for Employment…

Making Sense of Young People, Education and Digital Technology: The Role of Sociological Theory

ERIC Educational Resources Information Center

Selwyn, Neil

2012-01-01

This paper considers the contribution of sociological theory to the academic study of young people, education and digital technology. First it discusses the shortcomings of the technological and socially determinist views of technology and education that prevail in current academic and policy discussions. Against this background the paper outlines…

How Pennsylvania School Libraries Pay Off: Investments in Student Achievement and Academic Standards

ERIC Educational Resources Information Center

Lance, Keith Curry; Schwarz, Bill

2012-01-01

The purpose of this study was to examine the impact of Pennsylvania school library programs on student learning--specifically, the infrastructure (staffing, budgets, collections, technology, and access hours) that contributes most to student achievement, the costs and benefits associated with them, and the gap between current Pennsylvania school…

The Effects of Values, Work Centrality, and Organizational Commitment on Organizational Citizenship Behaviors: Evidence from Turkish SMEs

ERIC Educational Resources Information Center

Ucanok, Basak; Karabati, Serdar

2013-01-01

Organizational citizenship behaviors (OCBs) are voluntary contributions of employees not explicitly recognized by the formal reward system and are ultimately critical for sustaining organizational effectiveness (Organ, 1988). The current study aims to investigate the effects of values, work centrality, and organizational commitment on…

Evaluation of an International Roommate-Pairing Program

ERIC Educational Resources Information Center

Tolman, Steven

2016-01-01

There are over 700,000 international students currently studying in the U.S. (McMurtrie, 2011) contributing close to $12 billion yearly to the U.S. economy (Altbach, 2004). Universities cannot take for granted that international students will choose U.S. institutions. While great attention and research efforts have been given to support programs…

Self-Injurious Behavior in People with Profound Intellectual Disabilities: A Meta-Analysis of Single-Case Studies

ERIC Educational Resources Information Center

Denis, Jo; Van den Noortgate, Wim; Maes, Bea

2011-01-01

The limitations people with profound intellectual disabilities experience in functioning contribute to a vulnerability to self-injurious behavior. Since this problem behavior has important negative consequences for people concerned, examining the effectiveness of treatments is important. In the current meta-analysis, single-case studies…

Applying Mathematical Concepts with Hands-On, Food-Based Science Curriculum

ERIC Educational Resources Information Center

Roseno, Ashley T.; Carraway-Stage, Virginia G.; Hoerdeman, Callan; Díaz, Sebastián R.; Geist, Eugene; Duffrin, Melani W.

2015-01-01

This article addresses the current state of the mathematics education system in the United States and provides a possible solution to the contributing issues. As a result of lower performance in primary mathematics, American students are not acquiring the necessary quantitative literacy skills to become successful adults. This study analyzed the…

Evaluating and Improving the Mathematics Teaching-Learning Process through Metacognition

ERIC Educational Resources Information Center

Desoete, Annemie

2007-01-01

Introduction: Despite all the emphasis on metacognition, researchers currently use different techniques to assess metacognition. The purpose of this contribution is to help to clarify some of the paradigms on the evaluation of metacognition. In addition the paper reviews studies aiming to improve the learning process through metacognition. Method:…

Exploring College Counselor Spiritual Competency in Relation to Training and Professional Practice

ERIC Educational Resources Information Center

Conley, Abigail Holland

2012-01-01

The purpose of this mixed methods sequential explanatory study was to explore factors contributing to college counselors' spiritual competency by obtaining quantitative results from surveying 199 current members of the American College Counseling Association (ACCA) and then following up with 32 purposefully selected respondents based on high…

Enhanced photovoltaic performance of ultrathin Si solar cells via semiconductor nanocrystal sensitization: Energy transfer vs. optical coupling effects

DOE PAGES

Hoang, Son; Ashraf, Ahsan; Eisaman, Matthew D.; ...

2015-12-07

Excitonic energy transfer (ET) offers exciting opportunities for advances in optoelectronic devices such as solar cells. While recent experimental attempts have demonstrated its potential in both organic and inorganic photovoltaics (PVs), what remains to be addressed is quantitative understanding of how different ET modes contribute to PV performance and how ET contribution is differentiated from the classical optical coupling (OC) effects. In this study, we implement an ET scheme using a PV device platform, comprising CdSe/ZnS nanocrystal energy donor and 500 nm-thick ultrathin Si acceptor layers, and present the quantitative mechanistic description of how different ET modes, distinguished from themore » OC effects, increase the light absorption and PV efficiency. We find that nanocrystal sensitization enhances the short circuit current of ultrathin Si solar cells by up to 35%, of which the efficient ET, primarily driven by a long-range radiative mode, contributes to 38% of the total current enhancement. Lastly, these results not only confirm the positive impact of ET but also provide a guideline for rationally combining the ET and OC effects for improved light harvesting in PV and other optoelectronic devices.« less

Enhanced photovoltaic performance of ultrathin Si solar cells via semiconductor nanocrystal sensitization: energy transfer vs. optical coupling effects.

PubMed

Hoang, Son; Ashraf, Ahsan; Eisaman, Matthew D; Nykypanchuk, Dmytro; Nam, Chang-Yong

2016-03-21

Excitonic energy transfer (ET) offers exciting opportunities for advances in optoelectronic devices such as solar cells. While recent experimental attempts have demonstrated its potential in both organic and inorganic photovoltaics (PVs), what remains to be addressed is quantitative understanding of how different ET modes contribute to PV performance and how ET contribution is differentiated from the classical optical coupling (OC) effects. In this study, we implement an ET scheme using a PV device platform, comprising CdSe/ZnS nanocrystal energy donor and 500 nm-thick ultrathin Si acceptor layers, and present the quantitative mechanistic description of how different ET modes, distinguished from the OC effects, increase the light absorption and PV efficiency. We find that nanocrystal sensitization enhances the short circuit current of ultrathin Si solar cells by up to 35%, of which the efficient ET, primarily driven by a long-range radiative mode, contributes to 38% of the total current enhancement. These results not only confirm the positive impact of ET but also provide a guideline for rationally combining the ET and OC effects for improved light harvesting in PV and other optoelectronic devices.

Histiocytic proliferations.

PubMed

Ranganathan, Sarangarajan

2016-11-01

The study of Histiocytic lesions has been a passion of Pepper Dehner over the years. He has contributed several case series and reviews on various categories of these diseases for over 4 decades, with his earliest articles in the 1970s. He has written on all aspects of the disease including seminal articles on Langerhans cell histiocytosis (LCH) and their prognostic features, his experiences with regressing atypical histiocytosis, his encounters with malignant histiocytosis, and classic articles on juvenile xanthogranuloma. His contributions in the form of chapters in his 2 editions of the unique Pediatric Pathology textbook are no less important than his many articles. His experience with these lesions is highlighted in the 2 editions of the book, and the author and the audience is left wishing for more in a more current version. This article is more of a journey from descriptions and understanding of these various histiocytic syndromes to the current understanding and classifications with molecular inputs and recent advances. This article is dedicated to a master Clinician, Pathologist, and mentor whose contributions to the field of Pediatric Pathology makes him deserve beyond all doubt the title of "Father of Modern Pediatric Pathology." Copyright © 2016 Elsevier Inc. All rights reserved.

From past to current tectonics: Thematic issue dedicated to Jean-François Stéphan (1949-2013)

NASA Astrophysics Data System (ADS)

Manighetti, Isabelle

2016-01-01

This thematic issue of Comptes rendus Geoscience has been assembled to honor the memory of our late colleague and friend Jean-François Stéphan. Jean-François was a great scientist, specialized in tectonics, and a great colleague who devoted his time for his community. His work and actions deeply imprinted both the French and the International Earth Science communities. This volume brings together contributions of colleagues of Jean-François, who were also close friends or colleagues who knew and deeply appreciated him. Naturally, tectonics is the common theme of these contributions. Some of the papers presented here focus on tectonic questions and/or regions Jean-François worked on during his career; other papers present studies Jean-François motivated or encouraged in one way or another; other papers are simply tectonic studies he would have liked. Taken together, the nine papers of this thematic issue take the reader on a beautiful trip, from past to current tectonics.

A molecular dynamics study of liquid layering and thermal conductivity enhancement in nanoparticle suspensions

NASA Astrophysics Data System (ADS)

Paul, J.; Madhu, A. K.; Jayadeep, U. B.; Sobhan, C. B.; Peterson, G. P.

2018-03-01

Liquid layering is considered to be one of the factors contributing to the often anomalous enhancement in thermal conductivity of nanoparticle suspensions. The extent of this layering was found to be significant at lower particle sizes, as reported in an earlier work by the authors. In continuation to that work, an investigation was conducted to better understand the fundamental parameters impacting the reported anomalous enhancement in thermal conductivity of nanoparticle suspensions (nanofluids), utilizing equilibrium molecular dynamics simulations in a copper-argon system. Nanofluids containing nanoparticles of size less than 6 nm were investigated and studied analytically. The heat current auto-correlation function in the Green-Kubo formulation for thermal conductivity was decomposed into self-correlations and cross-correlations of different species and the kinetic, potential, collision and enthalpy terms of the dominant portion of the heat current vector. The presence of liquid layering around the nanoparticle was firmly established through simulations that show the dominant contribution of Ar-Ar self-correlation and the trend displayed by the kinetic-potential cross-correlation within the argon species.

Field Emission Enhancement and the Field-Screening Effect Reduction using Carbon Nanopipettes as Cold Cathodes

NASA Astrophysics Data System (ADS)

Safir, Abdelilah; Mudd, David; Yazdanpanah, Mehdi; Dobrokhotov, Vladimir; Sumanasekera, Gamini; Cohn, Robert

2008-03-01

In this work, we report a recent experimental study of high emission current densities exceeding 10mA/cm^2 and breakdown electric field lower than 5Volts/μm from novel cold cathodes such as conical shaped carbon nanopipettes (CNP). CNP were grown by CVD on Pt wire and have apex as sharp as 10nm with length between 3-6μm. The emission experiments were conducted under vacuum in a scanning electron microscope for individual CNP and in a dedicated chamber for bulk samples. CNP's conical bases and low density contribute significantly to the reduction of the screening effect and to the field emission enhancement. The experimental value for the field enhancement factor, γ, was about 867. Comparing emission results taken from CNP and aligned multiwall carbon nanotubes (MWNT) show that the ratio between γCNP and γMWNT is ˜1.6 which contributes to the reduction of screening effect. The emission from multilayers of graphene was also studied. High emission current (20μA) demonstrates promising emission properties of graphene.

Monitoring conservation effectiveness in a global biodiversity hotspot: the contribution of land cover change assessment.

PubMed

Joseph, Shijo; Blackburn, George Alan; Gharai, Biswadip; Sudhakar, S; Thomas, A P; Murthy, M S R

2009-11-01

Tropical forests, which play critical roles in global biogeochemical cycles, radiation budgets and biodiversity, have undergone rapid changes in land cover in the last few decades. This study examines the complex process of land cover change in the biodiversity hotspot of Western Ghats, India, specifically investigating the effects of conservation measures within the Indira Gandhi Wildlife Sanctuary. Current vegetation patterns were mapped using an IRS P6 LISS III image and this was used together with Landsat MSS data from 1973 to map land cover transitions. Two major and divergent trends were observed. A dominant degradational trend can be attributed to agricultural expansion and infrastructure development while a successional trend, resulting from protection of the area, showed the resilience of the system after prolonged disturbances. The sanctuary appears susceptible to continuing disturbances under the current management regime but at lower rates than in surrounding unprotected areas. The study demonstrates that remotely sensed land cover assessments can have important contributions to monitoring land management strategies, understanding processes underpinning land use changes and helping to inform future conservation strategies.

Misbehaving macrophages in the pathogenesis of psoriasis

PubMed Central

Clark, Rachael A.; Kupper, Thomas S.

2006-01-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin — or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell–mediated pathways of inflammation. PMID:16886055

Phytochemicals in whole grain wheat and their health-promoting effects.

PubMed

Zhu, Yingdong; Sang, Shengmin

2017-07-01

Accumulated evidence in epidemiological studies has consistently shown that consumption of whole grains (WGs) is inversely associated with risk of major chronic diseases such as certain types of cancer, type 2 diabetes, and cardiovascular diseases. Dietary fiber (DF) has been reported to be responsible for the health effects of WG consumption. Evidence from in vitro and in vivo studies is emerging that, in addition to DF and minerals, the unique phytochemicals in WGs may in part contribute to these health-promoting effects. WGs are rich sources of various phytochemicals. However, phytochemical contents and profiles in WG wheat are not systematically summarized yet, and the rapid rate of discovery of wheat phytochemicals necessitates an update on the current state of this field. Furthermore, the biological roles of phytochemicals in protective effects of WGs are also relatively underestimated compared to DFs. This manuscript summarized current research literature regarding phytochemicals that have been identified and characterized from wheat grains and wheat bran, and their corresponding contributions to the major health benefits of WG wheat consumption. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Exploring the relationship between time management skills and the academic achievement of African engineering students - a case study

NASA Astrophysics Data System (ADS)

Swart, Arthur James; Lombard, Kobus; de Jager, Henk

2010-03-01

Poor academic success by African engineering students is currently experienced in many higher educational institutions, contributing to lower financial subsidies by local governments. One of the contributing factors to this low academic success may be the poor time management skills of these students. This article endeavours to explore this relationship by means of a theoretical literature review and an empirical study. Numerous studies have been conducted in this regard, but with mixed results. The case study of this article involves a design module termed Design Projects III, where the empirical study incorporated an ex post facto study involving a pre-experimental/exploratory design using descriptive statistics. The results of this study were applied to various tests, which indicated no statistically significant relationship between time management skills and the academic achievement of African engineering students.

Different personal propensities among scientists relate to deeper vs. broader knowledge contributions

PubMed Central

Bateman, Thomas S.; Hess, Andrew M.

2015-01-01

Scientific journal publications, and their contributions to knowledge, can be described by their depth (specialized, domain-specific knowledge extensions) and breadth (topical scope, including spanning multiple knowledge domains). Toward generating hypotheses about how scientists’ personal dispositions would uniquely predict deeper vs. broader contributions to the literature, we assumed that conducting broader studies is generally viewed as less attractive (e.g., riskier) than conducting deeper studies. Study 1 then supported our assumptions: the scientists surveyed considered a hypothetical broader study, compared with an otherwise-comparable deeper study, to be riskier, a less-significant opportunity, and of lower potential importance; they further reported being less likely to pursue it and, in a forced choice, most chose to work on the deeper study. In Study 2, questionnaire measures of medical researchers’ personal dispositions and 10 y of PubMed data indicating their publications’ topical coverage revealed how dispositions differentially predict depth vs. breadth. Competitiveness predicted depth positively, whereas conscientiousness predicted breadth negatively. Performance goal orientation predicted depth but not breadth, and learning goal orientation contrastingly predicted breadth but not depth. Openness to experience positively predicted both depth and breadth. Exploratory work behavior (the converse of applying and exploiting one’s current knowledge) predicted breadth positively and depth negatively. Thus, this research distinguishes depth and breadth of published knowledge contributions, and provides new insights into how scientists’ personal dispositions influence research processes and products. PMID:25733900

Different personal propensities among scientists relate to deeper vs. broader knowledge contributions.

PubMed

Bateman, Thomas S; Hess, Andrew M

2015-03-24

Scientific journal publications, and their contributions to knowledge, can be described by their depth (specialized, domain-specific knowledge extensions) and breadth (topical scope, including spanning multiple knowledge domains). Toward generating hypotheses about how scientists' personal dispositions would uniquely predict deeper vs. broader contributions to the literature, we assumed that conducting broader studies is generally viewed as less attractive (e.g., riskier) than conducting deeper studies. Study 1 then supported our assumptions: the scientists surveyed considered a hypothetical broader study, compared with an otherwise-comparable deeper study, to be riskier, a less-significant opportunity, and of lower potential importance; they further reported being less likely to pursue it and, in a forced choice, most chose to work on the deeper study. In Study 2, questionnaire measures of medical researchers' personal dispositions and 10 y of PubMed data indicating their publications' topical coverage revealed how dispositions differentially predict depth vs. breadth. Competitiveness predicted depth positively, whereas conscientiousness predicted breadth negatively. Performance goal orientation predicted depth but not breadth, and learning goal orientation contrastingly predicted breadth but not depth. Openness to experience positively predicted both depth and breadth. Exploratory work behavior (the converse of applying and exploiting one's current knowledge) predicted breadth positively and depth negatively. Thus, this research distinguishes depth and breadth of published knowledge contributions, and provides new insights into how scientists' personal dispositions influence research processes and products.

Evidence that GABA ρ subunits contribute to functional ionotropic GABA receptors in mouse cerebellar Purkinje cells

PubMed Central

Harvey, Victoria L; Duguid, Ian C; Krasel, Cornelius; Stephens, Gary J

2006-01-01

Ionotropic γ-amino butyric acid (GABA) receptors composed of heterogeneous molecular subunits are major mediators of inhibitory responses in the adult CNS. Here, we describe a novel ionotropic GABA receptor in mouse cerebellar Purkinje cells (PCs) using agents reported to have increased affinity for ρ subunit-containing GABAC over other GABA receptors. Exogenous application of the GABAC-preferring agonist cis-4-aminocrotonic acid (CACA) evoked whole-cell currents in PCs, whilst equimolar concentrations of GABA evoked larger currents. CACA-evoked currents had a greater sensitivity to the selective GABAC antagonist (1,2,5,6-tetrahydropyridin-4-yl)methylphosphinic acid (TPMPA) than GABA-evoked currents. Focal application of agonists produced a differential response profile; CACA-evoked currents displayed a much more pronounced attenuation with increasing distance from the PC soma, displayed a slower time-to-peak and exhibited less desensitization than GABA-evoked currents. However, CACA-evoked currents were also completely blocked by bicuculline, a selective agent for GABAA receptors. Thus, we describe a population of ionotropic GABA receptors with a mixed GABAA/GABAC pharmacology. TPMPA reduced inhibitory synaptic transmission at interneurone–Purkinje cell (IN–PC) synapses, causing clear reductions in miniature inhibitory postsynaptic current (mIPSC) amplitude and frequency. Combined application of NO-711 (a selective GABA transporter subtype 1 (GAT-1) antagonist) and SNAP-5114 (a GAT-(2)/3/4 antagonist) induced a tonic GABA conductance in PCs; however, TPMPA had no effect on this current. Immunohistochemical studies suggest that ρ subunits are expressed predominantly in PC soma and proximal dendritic compartments with a lower level of expression in more distal dendrites; this selective immunoreactivity contrasted with a more uniform distribution of GABAA α1 subunits in PCs. Finally, co-immunoprecipitation studies suggest that ρ subunits can form complexes with GABAA receptor α1 subunits in the cerebellar cortex. Overall, these data suggest that ρ subunits contribute to functional ionotropic receptors that mediate a component of phasic inhibitory GABAergic transmission at IN–PC synapses in the cerebellum. PMID:16945976

Underlying Cause(s) of Letter Perseveration Errors

PubMed Central

Fischer-Baum, Simon; Rapp, Brenda

2011-01-01

Perseverations, the inappropriate intrusion of elements from a previous response into a current response, are commonly observed in individuals with acquired deficits. This study specifically investigates the contribution of failure-to activate and failure-to-inhibit deficit(s) in the generation of letter perseveration errors in acquired dysgraphia. We provide evidence from the performance 12 dysgraphic individuals indicating that a failure to activate graphemes for a target word gives rise to letter perseveration errors. In addition, we also provide evidence that, in some individuals, a failure-to-inhibit deficit may also contribute to the production of perseveration errors. PMID:22178232

Power characteristics in GMAW: Experimental and numerical investigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joensson, P.G.; Szekely, J.; Madigan, R.B.

1995-03-01

The voltage and power distributions in gas metal arc welding (GMAW) were studied both experimentally and numerically. The principal voltage drop takes place in the arc, which also constitutes the dominant power contribution. Within the arc, the dominating voltage contributions are from the arc column and the cathode fall, while the anode fall and the electrode regions are less significant. The power input to the arc column increases with both increasing current and increasing arc length. These results indicate that it is critical to control the arc length in order to control the power input to the system.

KASCADE-Grande: Composition studies in the view of the post-LHC hadronic interaction models

NASA Astrophysics Data System (ADS)

Haungs, A.; Apel, W. D.; Arteaga-Velázquez, J. C.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Pierro, F. Di; Doll, P.; Engel, R.; Fuhrmann, D.; Gherghel-Lascu, A.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Heck, D.; Hörandel, J. R.; Huege, T.; Kampert, K.-H.; Kang, D.; Klages, H. O.; Link, K.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Oehlschläger, J.; Ostapchenko, S.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schoo, S.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Zabierowski, J.

2017-06-01

The KASCADE-Grande experiment has significantly contributed to the current knowledge about the energy spectrum and composition of cosmic rays for energies between the knee and the ankle. Meanwhile, post-LHC versions of the hadronic interaction models are available and used to interpret the entire data set of KASCADE-Grande. In addition, a new, combined analysis of both arrays, KASCADE and Grande, was developed significantly increasing the accuracy of the shower observables. First results of the new analysis with the entire data set of the KASCADE-Grande experiment will be the focus of this contribution.

Higgs boson gluon-fusion production beyond threshold in N 3LO QCD

DOE PAGES

Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko; ...

2015-03-18

In this study, we compute the gluon fusion Higgs boson cross-section at N 3LO through the second term in the threshold expansion. This calculation constitutes a major milestone towards the full N 3LO cross section. Our result has the best formal accuracy in the threshold expansion currently available, and includes contributions from collinear regions besides subleading corrections from soft and hard regions, as well as certain logarithmically enhanced contributions for general kinematics. We use our results to perform a critical appraisal of the validity of the threshold approximation at N 3LO in perturbative QCD.

The Cloud Feedback Model Intercomparison Project (CFMIP) Diagnostic Codes Catalogue – metrics, diagnostics and methodologies to evaluate, understand and improve the representation of clouds and cloud feedbacks in climate models

DOE PAGES

Tsushima, Yoko; Brient, Florent; Klein, Stephen A.; ...

2017-11-27

The CFMIP Diagnostic Codes Catalogue assembles cloud metrics, diagnostics and methodologies, together with programs to diagnose them from general circulation model (GCM) outputs written by various members of the CFMIP community. This aims to facilitate use of the diagnostics by the wider community studying climate and climate change. Here, this paper describes the diagnostics and metrics which are currently in the catalogue, together with examples of their application to model evaluation studies and a summary of some of the insights these diagnostics have provided into the main shortcomings in current GCMs. Analysis of outputs from CFMIP and CMIP6 experiments willmore » also be facilitated by the sharing of diagnostic codes via this catalogue. Any code which implements diagnostics relevant to analysing clouds – including cloud–circulation interactions and the contribution of clouds to estimates of climate sensitivity in models – and which is documented in peer-reviewed studies, can be included in the catalogue. We very much welcome additional contributions to further support community analysis of CMIP6 outputs.« less

The Cloud Feedback Model Intercomparison Project (CFMIP) Diagnostic Codes Catalogue – metrics, diagnostics and methodologies to evaluate, understand and improve the representation of clouds and cloud feedbacks in climate models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsushima, Yoko; Brient, Florent; Klein, Stephen A.

The CFMIP Diagnostic Codes Catalogue assembles cloud metrics, diagnostics and methodologies, together with programs to diagnose them from general circulation model (GCM) outputs written by various members of the CFMIP community. This aims to facilitate use of the diagnostics by the wider community studying climate and climate change. Here, this paper describes the diagnostics and metrics which are currently in the catalogue, together with examples of their application to model evaluation studies and a summary of some of the insights these diagnostics have provided into the main shortcomings in current GCMs. Analysis of outputs from CFMIP and CMIP6 experiments willmore » also be facilitated by the sharing of diagnostic codes via this catalogue. Any code which implements diagnostics relevant to analysing clouds – including cloud–circulation interactions and the contribution of clouds to estimates of climate sensitivity in models – and which is documented in peer-reviewed studies, can be included in the catalogue. We very much welcome additional contributions to further support community analysis of CMIP6 outputs.« less

Induction of oxidative stress by bisphenol A and its pleiotropic effects

PubMed Central

Gassman, Natalie R.

2016-01-01

Bisphenol A (BPA) has become a target of intense public scrutiny since concerns about its association with human diseases such as obesity, diabetes, reproductive disorders, and cancer have emerged. BPA is a highly prevalent chemical in consumer products, and human exposure is thought to be ubiquitous. Numerous studies have demonstrated its endocrine disrupting properties and attributed exposure with cytotoxic, genotoxic, and carcinogenic effects; however, the results of these studies are still highly debated and a consensus about BPA's safety and its role in human disease has not been reached. One of the contributing factors is a lack of molecular mechanisms or modes of action that explain the diverse and pleiotropic effects observed after BPA exposure. The increase in BPA research seen over the last ten years has resulted in more studies that examine molecular mechanisms and revealed links between BPA-induced oxidative stress and human disease. Here, a review of the current literature examining BPA exposure and the induction of reactive oxygen species (ROS) or oxidative stress will be provided to examine the landscape of the current BPA literature and provide a framework for understanding how induction of oxidative stress by BPA may contribute to the pleiotropic effects observed after exposure. PMID:28181297

Altered physiological functions and ion currents in atrial fibroblasts from patients with chronic atrial fibrillation.

PubMed

Poulet, Claire; Künzel, Stephan; Büttner, Edgar; Lindner, Diana; Westermann, Dirk; Ravens, Ursula

2016-02-01

The contribution of human atrial fibroblasts to cardiac physiology and pathophysiology is poorly understood. Fibroblasts may contribute to arrhythmogenesis through fibrosis, or by directly altering electrical activity in cardiomyocytes. The objective of our study was to uncover phenotypic differences between cells from patients in sinus rhythm (SR) and chronic atrial fibrillation (AF), with special emphasis on electrophysiological properties. We isolated fibroblasts from human right atrial tissue for patch-clamp experiments, proliferation, migration, and differentiation assays, and gene expression profiling. In culture, proliferation and migration of AF fibroblasts were strongly impaired but differentiation into myofibroblasts was increased. This was associated with a higher number of AF fibroblasts expressing functional Nav1.5 channels. Strikingly Na(+) currents were considerably larger in AF cells. Blocking Na(+) channels in culture with tetrodotoxin did not affect proliferation, migration, or differentiation in neither SR nor AF cells. While freshly isolated fibroblasts showed mostly weak rectifier currents, fibroblasts in culture developed outward rectifier K(+) currents of similar amplitude between the SR and AF groups. Adding the K(+) channel blockers tetraethylammonium and 4-aminopyridin in culture reduced current amplitude and inhibited proliferation in the SR group only. Analysis of gene expression revealed significant differences between SR and AF in genes encoding for ion channels, collagen, growth factors, connexins, and cadherins. In conclusion, this study shows that under AF conditions atrial fibroblasts undergo phenotypic changes that are revealed in culture. Future experiments should be performed in situ to understand the nature of those changes and whether they affect cardiac electrical activity. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Model testing on the crisis interventions and actions to prevent medical disputes: a Taiwanese nursing perspective.

PubMed

Tzeng, Huey-Ming

2006-05-01

This study investigated the contributions of comprehensiveness and necessity scales on crisis interventions and actions toward nursing practice-related medical disputes in Taiwanese hospitals and institutions' demographic characteristics, to overall satisfaction toward nursing-related crisis management policies and interventions and overall satisfaction toward their institution's crisis management system. In a health-care environment that is focused on cost containment, for overworked nurses and understaffed medical wards, patients still expect nurses to provide high quality, compassionate care. Patients usually regard nurses as the principal link between the technical and interpersonal aspects of their care. However, current hospital systems tend to require patients to be self-reliant in managing their own care. Patient mistrust of medical care providers might have contributed to the current medical error/dispute crisis. In this cross-sectional study, the subjects were nursing directors of Taiwanese hospitals (197 valid subjects). The author developed the questionnaire used in this study. The ordinal logistic regression analyses demonstrated that being a public hospital managed by the government, being a hospital operated by a corporate body, the more comprehensive the technical/structural aspect and the assessment aspect and the more needed the psychological aspect, contribute to higher general satisfaction levels toward nursing-related crisis management. The more comprehensive the strategic aspect and having more acute beds, contributes to higher satisfaction levels with their institution's overall crisis management activities. These findings inferred a possible change in a hospital's resource allocation or power structure when dealing with issues of patient care quality, including nursing practice-related crisis management policies, interventions and actions. RELEVANT TO CLINICAL PRACTICE: A good crisis management system may help to keep a crisis from worsening, which might lead to a serious situation that includes malpractice litigation. It is believed that the questionnaire used in this study may be used as a diagnostic tool for assessing a crisis management system within a hospital's nursing environment.

Uneven biofilm and current distribution in three-dimensional macroporous anodes of bio-electrochemical systems composed of graphite electrode arrays.

PubMed

Li, Jun; Hu, Linbin; Zhang, Liang; Ye, Ding-Ding; Zhu, Xun; Liao, Qiang

2017-03-01

A 3-D macroporous anode was constructed using different numbers of graphite rod arrays in fixed-volume bio-electrochemical systems (BESs), and the current and biofilm distribution were investigated by dividing the 3-D anode into several subunits. In the fixed-volume chamber, current production was not significantly improved after the electrode number increased to 36. In the case of 100 electrodes, a significant uneven current distribution was found in the macroporous anode. This was attributed to a differential pH distribution, which resulted from proton accumulation inside the macroporous anode. The pH distribution influenced the biofilm development and led to an uneven biofilm distribution. With respect to current generation, the uneven distribution of both the pH and biofilm contributed to the uneven current distribution. The center had a low pH, which led to less biofilm and a lower contribution to the total current, limiting the performance of the BESs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Axial U(1) current in Grabowska and Kaplan's formulation

NASA Astrophysics Data System (ADS)

Hamada, Yu; Kawai, Hikaru

2017-06-01

Recently, Grabowska and Kaplan [Phys. Rev. Lett. 116, 211602 (2016); Phys. Rev. D 94, 114504 (2016)] suggested a nonperturbative formulation of a chiral gauge theory, which consists of the conventional domain-wall fermion and a gauge field that evolves by gradient flow from one domain wall to the other. We introduce two sets of domain-wall fermions belonging to complex conjugate representations so that the effective theory is a 4D vector-like gauge theory. Then, as a natural definition of the axial-vector current, we consider a current that generates simultaneous phase transformations for the massless modes in 4 dimensions. However, this current is exactly conserved and does not reproduce the correct anomaly. In order to investigate this point precisely, we consider the mechanism of the conservation. We find that this current includes not only the axial current on the domain wall but also a contribution from the bulk, which is nonlocal in the sense of 4D fields. Therefore, the local current is obtained by subtracting the bulk contribution from it.

A new data-based model of the global magnetospheric B-field: Modular structure, parameterization, first results.

NASA Astrophysics Data System (ADS)

Tsyganenko, Nikolai

2013-04-01

A new advanced model of the dynamical geomagnetosphere is presented, based on a large set of data from Geotail, Cluster, Polar, and Themis missions, taken during 138 storm events with SYM-H from -40 to -487nT over the period from 1996 through 2012 in the range of geocentric distances from ~3Re to ~60Re. The model magnetic field is confined within a realistic magnetopause, based on Lin et al. [JGRA, v.115, A04207, 2010] empirical boundary, driven by the dipole tilt angle, solar wind pressure, and IMF Bz. The magnetic field is modeled as a flexible combination of several modules, representing contributions from principal magnetospheric current systems such as the symmetric and partial ring currents (SRC/PRC), Region 1 and 2 field-aligned currents (FAC), and the equatorial tail current sheet (TCS). In the inner magnetosphere the model field is dominated by contributions from the SRC and PRC, derived from realistic particle pressure models and represented by four modules, providing variable degree of dawn-dusk and noon-midnight asymmetry. The TCS field is comprised of several independent modules, ensuring sufficient flexibility of the model field and correct asymptotic values in the distant tail. The Region 2 FAC is an inherent part of the PRC, derived from the continuity of the azimuthal current. The Region 1 FAC is modulated by the diurnal and seasonal variations of the dipole tilt angle, in agreement with earlier statistical studies [Ohtani et al., JGRA, v.110, A09230, 2005]. Following the approach introduced in our earlier TS05 model [Tsyganenko and Sitnov, JGRA, v.110, A03208, 2005], contributions from all individual field sources are parameterized by the external driving functions, derived from the solar wind/IMF OMNI database as solutions of dynamic equations with source and loss terms in the right-hand side. Global magnetic configurations and their evolution during magnetospheric storms are analyzed and discussed in context of the model results.

Inertial Currents in Isotropic Plasma

NASA Technical Reports Server (NTRS)

Heinemann, M.; Erickson, G. M.; Pontius, D. H., Jr.

1993-01-01

The magnetospheric convection electric field contributes to Birkeland currents. The effects of the field are to polarize the plasma by displacing the bounce paths of the ions from those of electrons, to redistribute the pressure so that it is not constant along magnetic field lines, and to enhance the pressure gradient by the gradient of the bulk speed. Changes in the polarization charge during the convection of the plasma are neutralized by electrons in the form of field-aligned currents that close through the ionosphere. The pressure drives field-aligned currents through its gradient in the same manner as in quasi-static plasma, but with modifications that are important if the bulk speed is of the order of the ion thermal speed; the variations in the pressure along field lines are maintained by a weak parallel potential drop. These effects are described in terms of the field-aligned currents in steady state, isotropic, MED plasma. Solutions are developed by taking the MHD limit of two-fluid solutions and illustrated in the special case of Maxwellian plasma for which the temperature is constant along magnetic field lines. The expression for the Birkeland current density is a generalization of Vasyliunas' expression for the field-aligned current density in quasi-static plasma and provides a unifying expression when both pressure gradients and ion inertia operate simultaneously as sources of field-aligned currents. It contains a full account of different aspects of the ion flow (parallel and perpendicular velocity and vorticity) that contribute to the currents. Contributions of ion inertia to field-aligned currents will occur in regions of strong velocity shear, electric field reversal, or large gradients in the parallel velocity or number density, and may be important in the low-latitude boundary layer, plasma sheet boundary layer, and the inner edge region of the plasma sheet.

Inertial currents in isotropic plasma

NASA Technical Reports Server (NTRS)

Heinemann, M.; Erickson, G. M.; Pontius, D. H. JR.

1994-01-01

The magnetospheric convection electric field contributes to Birkeland currents. The effects of the field are to polarize the plasma by displacing the bounce paths of the ions from those of electrons, to redistribute the pressure so that it is not constant along magnetic field lines, and to enhance the pressure gradient by the gradient of the bulk speed. Changes in the polarization charge during the convection of the plasma are neutralized by electrons in the form of field-aligned currents that close through the ionosphere. The pressure drives field-aligned currents through its gradient in the same manner as in quasi-static plasma, but with modifications that are important if the bulk speed is of the order of the ion thermal speed; the variations in the pressure along field lines are maintained by a weak parallel potential drop. These effects are described in terms of the field-aligned currents in steady state, isotropic, magnetohyrodynamic (MHD) plasma. Solutions are developed by taking the MHD limit of two-fluid solutions and illustrated in the special case of Maxwellian plasma for which the temperature is constant along magnetic field lines. The expression for the Birkeland current density is a generalization of Vasyliunas' expression for the field-aligned current density in quasi-static plasma and provides a unifying expression when both pressure gradients and ion inertia operate simultaneously as sources of field-aligned currents. It contains a full account of different aspects of the ion flow (parallel and perpendicular velocity and vorticity) that contribute to the currents. Contributions of ion inertia to field-aligned currents will occur in regions of strong velocity shear, electric field reversal, or large gradients in the parallel velocity or number density, and may be important in the low-latitude boundary layer, plasma sheet boundary layer, and the inner edge region of the plasma sheet.

Inertial currents in isotropic plasma

NASA Technical Reports Server (NTRS)

Heinemann, M.; Erickson, G. M.; Pontius, D. H., Jr.

1994-01-01

The magnetospheric convection electric field contributes to Birkeland currents. The effects of the field are to polarize the plasma by displacing the bounce paths of the ions from those of electrons, to redistribute the pressure so that it is not constant along magnetic field lines, and to enhance the pressure gradient by the gradient of the bulk speed. Changes in the polarization charge during the convection of the plasma are neutralized by electrons in the form of field-aligned currents that close through the ionosphere. The pressure drives field-aligned currents through its gradient in the same manner as in quasi-static plasmas, but with modifications that are important if the bulk speed is of the order of the ion thermal speed; the variations in the pressure along field lines are maintained by a weak parallel potential drop. These effects are described in terms of the field-aligned currents in steady state, isotropic, MHD plasma. Solutions are developed by taking the MHD limit ot two-fluid solutions and illustrated in the special case of Maxwellian plasma for which the temperature is constant along magnetic field lines. The expression for the Birkeland current density is a generalization of Vasyliunas' expression for the field-aligned current density in quasi-static plasma and provides a unifying expression when both pressure gradients and ion inertia operate simultaneously as sources of field-aligned currents. It contains a full account of different aspects of the ion flow (parallel and perpendicular velocity and vorticity) that contribute to the currents. Contributions of ion inertia to field-aligned currents will occur in regions of strong velocity shear, electric field reversal, or large gradients in the parallel velocity or number density, and may be important in the low-latitude boundary layer, plasma sheet boundary layer, and the inner edge region of the plasma sheet.

Overview of the determinants of overweight and obesity: current evidence and research issues.

PubMed

Hill, J O; Melanson, E L

1999-11-01

The prevalence of obesity has reached epidemic proportions in many countries around the world. However, the genetic and environmental factors contributing to obesity are incompletely understood. We reviewed studies relating to the regulation of energy balance and how these factors may contribute to the development of obesity. Although it is widely believed that genetics contribute significantly to the variability in body fatness, the available data do not support a role for defects in resting metabolic rate, substrate metabolism, dietary induced thermogenesis, or the energy cost of physical activity as significant causes of obesity. Furthermore, it is safe to say that the human genotype has not changed substantially over the past two to three decades. Data from several national surveys indicate that over the past few decades, there has been either a slight increase or a very modest decline in total energy and fat intake. This suggests that decreases in physical activity are a major contributing factor. Participation in leisure time physical activity is low but has remained relatively constant. However, an increased reliance on technology has substantially reduced work-related physical activity and the energy expenditure required for daily living. The most likely environmental factor contributing to the current obesity epidemic is a continued decline in daily energy expenditure that has not been matched by an equivalent reduction in energy intake. Because daily energy expenditure is decreasing, it is difficult for most people to restrict intake to meet energy requirements, and more and more people are becoming obese. Thus, increasing physical activity may be the strategy of choice for public health efforts to prevent obesity.

Evaluation of the Eological Management and Enhancement Alernative for Remediation of the K1007-P1 Pond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, M.J.

2005-10-31

An evaluation of the human and ecological risks associated with the P1 Pond and surrounding environs was conducted as part of the ETTP Site-Wide Remedial Investigation. The RI provides the basis for the focus on PCBs as the most important unacceptable risk to human and ecological health in the pond. Other P1 contaminants, media, or pathways of risk to receptors are identified in the RI, but are not addressed as a major risk reduction goal for the ETTP Site-Wide Feasibility Study. Therefore, the goal of the Ecological Management alternative is to reduce unacceptable risks associated with PCBs in fish. Manymore » of the actions proposed for this alternative, however, are likely to reduce risks associated with other contaminants and their pathways. The high PCB concentrations in fish from the P1 Pond are most certainly due in part to the current ecological condition of the pond that maximizes PCB biomagnification. This basic assumption and the factors contributing to it were evaluated by conducting an intensive field study of the P1 Pond in the summer of 2004 (for a thorough presentation of current P1 Pond biological conditions, see Peterson et al. 2005). Major hypotheses regarding the P1 Pond's current fish community, PCB fate and transport processes, pond vegetation, and limnological conditions that contribute to the high PCB levels in fish were validated by the study (Appendix A), The results of the 2004 ecological assessment, in concert with long-term datasets obtained as part of the ETTP Biological Monitoring and Abatement Program (BMAP) and recent abiotic sampling for the RI, provide the basis for the assessment of current conditions.« less

Unusual Voltage-Gated Sodium Currents as Targets for Pain.

PubMed

Barbosa, C; Cummins, T R

2016-01-01

Pain is a serious health problem that impacts the lives of many individuals. Hyperexcitability of peripheral sensory neurons contributes to both acute and chronic pain syndromes. Because voltage-gated sodium currents are crucial to the transmission of electrical signals in peripheral sensory neurons, the channels that underlie these currents are attractive targets for pain therapeutics. Sodium currents and channels in peripheral sensory neurons are complex. Multiple-channel isoforms contribute to the macroscopic currents in nociceptive sensory neurons. These different isoforms exhibit substantial variations in their kinetics and pharmacology. Furthermore, sodium current complexity is enhanced by an array of interacting proteins that can substantially modify the properties of voltage-gated sodium channels. Resurgent sodium currents, atypical currents that can enhance recovery from inactivation and neuronal firing, are increasingly being recognized as playing potentially important roles in sensory neuron hyperexcitability and pain sensations. Here we discuss unusual sodium channels and currents that have been identified in nociceptive sensory neurons, describe what is known about the molecular determinants of the complex sodium currents in these neurons. Finally, we provide an overview of therapeutic strategies to target voltage-gated sodium currents in nociceptive neurons. Copyright © 2016 Elsevier Inc. All rights reserved.

Insights into Brown Adipose Tissue Physiology as Revealed by Imaging Studies

PubMed Central

Izzi-Engbeaya, Chioma; Salem, Victoria; Atkar, Rajveer S; Dhillo, Waljit S

2014-01-01

There has been resurgence in interest in brown adipose tissue (BAT) following radiological and histological identification of metabolically active BAT in adult humans. Imaging enables BAT to be studied non-invasively and therefore imaging studies have contributed a significant amount to what is known about BAT function in humans. In this review the current knowledge (derived from imaging studies) about the prevalence, function, activity and regulation of BAT in humans (as well as relevant rodent studies), will be summarized. PMID:26167397

Absence of anomalous Nernst effect in spin Seebeck effect of Pt/YIG

DOE PAGES

Miao, B. F.; Huang, S. Y.; Qu, D.; ...

2016-01-29

The Pt/YIG structure has been widely used to study spin Seebeck effect (SSE), inverse spin Hall effect, and other pure spin current phenomena. However, the magnetic proximity effect in Pt when in contact with YIG, and the potential anomalous Nernst effect (ANE) may compromise the spin current phenomena in Pt/YIG. By inserting a Cu layer of various thicknesses between Pt and YIG, we have separated the signals from the SSE and that of the ANE. Here, it is demonstrated that the thermal voltage in Pt/YIG mainly comes from spin current due to the longitudinal SSE with negligible contribution from themore » ANE.« less

The contribution of physical activity and media use during childhood and adolescence to adult women's body image.

PubMed

Slater, Amy; Tiggemann, Marika

2006-07-01

This study aimed to investigate the effects of both past and current physical activity and media use on women's body image. A sample of 144 female undergraduate students completed measures of current physical activity, media use and body image, as well as providing retrospective reports of their physical activity participation and media usage during childhood and adolescence. Regression analyses showed that childhood experiences of physical activity and media use predicted adult body-image concerns more strongly than current activities. It was concluded that early experiences of both physical activity and media use during childhood and adolescence play an important role in the development of adult women's body image.

Role of Ureaplasma Respiratory Tract Colonization in Bronchopulmonary Dysplasia Pathogenesis: Current Concepts and Update.

PubMed

Viscardi, Rose Marie; Kallapur, Suhas G

2015-12-01

Respiratory tract colonization with the genital mycoplasma species Ureaplasma parvum and Ureaplasma urealyticum in preterm infants is a significant risk factor for bronchopulmonary dysplasia (BPD). Recent studies of the ureaplasmal genome, animal infection models, and human infants have provided a better understanding of specific virulence factors, pathogen-host interactions, and variability in genetic susceptibility that contribute to chronic infection, inflammation, and altered lung development. This review provides an update on the current evidence supporting a causal role of ureaplasma infection in BPD pathogenesis. The current status of antibiotic trials to prevent BPD in Ureaplasma-infected preterm infants is also reviewed. Copyright © 2015 Elsevier Inc. All rights reserved.

Inverse spin Hall and spin rectification effects in NiFe/FeMn exchange-biased thin films

NASA Astrophysics Data System (ADS)

Garcia, W. J. S.; Seeger, R. L.; da Silva, R. B.; Harres, A.

2017-11-01

Materials presenting high spin-orbit coupling are able to convert spin currents in charge currents. The phenomenon, known as inverse spin Hall effect, promises to revolutionize spintronic technology enabling the electrical detection of spin currents. It has been observed in a variety of systems, usually non-magnetic metals. We study the voltage emerging in exchange biased Ta/NiFe/FeMn/Ta thin films near the ferromagnetic resonance. Measured signals are related to both inverse spin Hall and spin rectification effects, and two distinct protocols were employed to separate their contributions.The curve shift due to the exchange bias effect may enable high frequency applications without an external applied magnetic field.

A modeling study of the time-averaged electric currents in the vicinity of isolated thunderstorms

NASA Technical Reports Server (NTRS)

Driscoll, Kevin T.; Blakeslee, Richard J.; Baginski, Michael E.

1992-01-01

A thorough examination of the results of a time-dependent computer model of a dipole thunderstorm revealed that there are numerous similarities between the time-averaged electrical properties and the steady-state properties of an active thunderstorm. Thus, the electrical behavior of the atmosphere in the vicinity of a thunderstorm can be determined with a formulation similar to what was first described by Holzer and Saxon (1952). From the Maxwell continuity equation of electric current, a simple analytical equation was derived that expresses a thunderstorm's average current contribution to the global electric circuit in terms of the generator current within the thundercloud, the intracloud lightning current, the cloud-to-ground lightning current, the altitudes of the charge centers, and the conductivity profile of the atmosphere. This equation was found to be nearly as accurate as the more computationally expensive numerical model, even when it is applied to a thunderstorm with a reduced conductivity thundercloud, a time-varying generator current, a varying flash rate, and a changing lightning mix.

Evaluation of the Current Status and Knowledge Contributions of Professional Doctorates

ERIC Educational Resources Information Center

Costley, Carol

2013-01-01

The article examines the status and knowledge contributions of professional doctorates (PDs) undertaken by practising professionals who in most cases are not intending to join the academic community. The purpose of these doctorates is usually to research and develop an original contribution to practice through practitioner-research. Giving greater…

The strange and charm quark contributions to the anomalous magnetic moment of the muon from lattice QCD

NASA Astrophysics Data System (ADS)

Koponen, Jonna; Chakraborty, Bipasha; Davies, Christine T. H.; Donald, Gordon; Dowdall, Rachel; Gonçalves de Oliveira, Pedro; Lepage, G. Peter; Teubner, Thomas

2016-04-01

We describe a new technique (published in [1]) to determine the contribution to the anomalous magnetic moment of the muon coming from the hadronic vacuum polarisation using lattice QCD. Our method uses Padé approximants to reconstruct the Adler function from its derivatives at q2 = 0. These are obtained simply and accurately from time-moments of the vector current-current correlator at zero spatial momentum. We test the method using strange quark correlators calculated on MILC Collaboration's nf = 2 + 1 + 1 HISQ ensembles at multiple values of the lattice spacing, multiple volumes and multiple light sea quark masses (including physical pion mass configurations). We find the (connected) contribution to the anomalous moment from the strange quark vacuum polarisation to be aμs = 53.41 (59) ×10-10, and the contribution from charm quarks to be aμc = 14.42 (39) ×10-10 - 1% accuracy is achieved for the strange quark contribution. The extension of our method to the light quark contribution and to that from the quark-line disconnected diagram is straightforward.

Mental Health Difficulties among Young People on the Autistic Spectrum in Mainstream Secondary Schools: A Comparative Study

ERIC Educational Resources Information Center

Hebron, Judith; Humphrey, Neil

2014-01-01

Young people on the autistic spectrum (AS) may be at an increased risk of developing mental health difficulties, but to date research evidence has been equivocal and/or inadequate. The aim of the current study was to document the mental health profiles of adolescents on the AS, and to identify factors that contribute to difficulties in this area.…

An Improved NDE (Non-Destructive Evaluation) Capability for Aerospace Components.

DTIC Science & Technology

1984-12-21

proposed design will use the scintillator/fiber-optic Reticon detector which was investigated in the eperimental studies discussed above. The x rays...practical operation. Experimental studies of a microfocal x-ray source and the SFRD pinpointed current proklems and capabilities. A conceptual design ...authors would like to acknowledge the following important contributions to this effort: Chuck Isaacson for his help in the design and implementation of

Contribution of Kv2.1 channels to the delayed rectifier current in freshly dispersed smooth muscle cells from rabbit urethra.

PubMed

Kyle, B; Bradley, E; Ohya, S; Sergeant, G P; McHale, N G; Thornbury, K D; Hollywood, M A

2011-11-01

We have characterized the native voltage-dependent K(+) (K(v)) current in rabbit urethral smooth muscle cells (RUSMC) and compared its pharmacological and biophysical properties with K(v)2.1 and K(v)2.2 channels cloned from the rabbit urethra and stably expressed in human embryonic kidney (HEK)-293 cells (HEK(Kv2.1) and HEK(Kv2.2)). RUSMC were perfused with Hanks' solution at 37°C and studied using the patch-clamp technique with K(+)-rich pipette solutions. Cells were bathed in 100 nM Penitrem A (Pen A) to block large-conductance Ca(2+)-activated K(+) (BK) currents and depolarized to +40 mV for 500 ms to evoke K(v) currents. These were unaffected by margatoxin, κ-dendrotoxin, or α-dendrotoxin (100 nM, n = 3-5) but were blocked by stromatoxin-1 (ScTx, IC(50) ∼130 nM), consistent with the idea that the currents were carried through K(v)2 channels. RNA was detected for K(v)2.1, K(v)2.2, and the silent subunit K(v)9.3 in urethral smooth muscle. Immunocytochemistry showed membrane staining for both K(v)2 subtypes and K(v)9.3 in isolated RUSMC. HEK(Kv2.1) and HEK(Kv2.2) currents were blocked in a concentration-dependent manner by ScTx, with estimated IC(50) values of ∼150 nM (K(v)2.1, n = 5) and 70 nM (K(v)2.2, n = 6). The mean half-maximal voltage (V(1/2)) of inactivation of the USMC K(v) current was -56 ± 3 mV (n = 9). This was similar to the HEK(Kv2.1) current (-55 ± 3 mV, n = 13) but significantly different from the HEK(Kv2.2) currents (-30 ± 3 mV, n = 11). Action potentials (AP) evoked from RUSMC studied under current-clamp mode were unaffected by ScTx. However, when ScTx was applied in the presence of Pen A, the AP duration was significantly prolonged. Similarly, ScTx increased the amplitude of spontaneous contractions threefold, but only after Pen A application. These data suggest that K(v)2.1 channels contribute significantly to the K(v) current in RUSMC.

Contribution of Kv2.1 channels to the delayed rectifier current in freshly dispersed smooth muscle cells from rabbit urethra

PubMed Central

Kyle, B.; Bradley, E.; Ohya, S.; Sergeant, G. P.; McHale, N. G.; Thornbury, K. D.

2011-01-01

We have characterized the native voltage-dependent K+ (Kv) current in rabbit urethral smooth muscle cells (RUSMC) and compared its pharmacological and biophysical properties with Kv2.1 and Kv2.2 channels cloned from the rabbit urethra and stably expressed in human embryonic kidney (HEK)-293 cells (HEKKv2.1 and HEKKv2.2). RUSMC were perfused with Hanks′ solution at 37°C and studied using the patch-clamp technique with K+-rich pipette solutions. Cells were bathed in 100 nM Penitrem A (Pen A) to block large-conductance Ca2+-activated K+ (BK) currents and depolarized to +40 mV for 500 ms to evoke Kv currents. These were unaffected by margatoxin, κ-dendrotoxin, or α-dendrotoxin (100 nM, n = 3–5) but were blocked by stromatoxin-1 (ScTx, IC50 ∼130 nM), consistent with the idea that the currents were carried through Kv2 channels. RNA was detected for Kv2.1, Kv2.2, and the silent subunit Kv9.3 in urethral smooth muscle. Immunocytochemistry showed membrane staining for both Kv2 subtypes and Kv9.3 in isolated RUSMC. HEKKv2.1 and HEKKv2.2 currents were blocked in a concentration-dependent manner by ScTx, with estimated IC50 values of ∼150 nM (Kv2.1, n = 5) and 70 nM (Kv2.2, n = 6). The mean half-maximal voltage (V1/2) of inactivation of the USMC Kv current was −56 ± 3 mV (n = 9). This was similar to the HEKKv2.1 current (−55 ± 3 mV, n = 13) but significantly different from the HEKKv2.2 currents (−30 ± 3 mV, n = 11). Action potentials (AP) evoked from RUSMC studied under current-clamp mode were unaffected by ScTx. However, when ScTx was applied in the presence of Pen A, the AP duration was significantly prolonged. Similarly, ScTx increased the amplitude of spontaneous contractions threefold, but only after Pen A application. These data suggest that Kv2.1 channels contribute significantly to the Kv current in RUSMC. PMID:21813710

Nuclear axial currents in chiral effective field theory

DOE PAGES

Baroni, Alessandro; Girlanda, Luca; Pastore, Saori; ...

2016-01-11

Two-nucleon axial charge and current operators are derived in chiral effective field theory up to one loop. The derivation is based on time-ordered perturbation theory and accounts for cancellations between the contributions of irreducible diagrams and the contributions owing to nonstatic corrections from energy denominators of reducible diagrams. Ultraviolet divergencies associated with the loop corrections are isolated in dimensional regularization. The resulting axial current is finite and conserved in the chiral limit, while the axial charge requires renormalization. As a result, a complete set of contact terms for the axial charge up to the relevant order in the power countingmore » is constructed.« less

Impact and promise of NASA aeropropulsion technology

NASA Technical Reports Server (NTRS)

Saunders, Neal T.; Bowditch, David N.

1990-01-01

The aeropropulsion industry in the U.S. has established an enviable record of leading the world in aeropropulsion for commercial and military aircraft. NASA's aeropropulsion program (primarily conducted through the Lewis Research Center) has significantly contributed to that success through research and technology advances and technology demonstration. Some past NASA contributions to engines in current aircraft are reviewed, and technologies emerging from current research programs for the aircraft of the 1990's are described. Finally, current program thrusts toward improving propulsion systems in the 2000's for subsonic commercial aircraft and higher speed aircraft such as the High-Speed Civil Transport and the National Aerospace Plane are discussed.

Human Gut Microbiome: Function Matters.

PubMed

Heintz-Buschart, Anna; Wilmes, Paul

2017-11-22

The human gut microbiome represents a complex ecosystem contributing essential functions to its host. Recent large-scale metagenomic studies have provided insights into its structure and functional potential. However, the functional repertoire which is actually contributed to human physiology remains largely unexplored. Here, by leveraging recent omics datasets, we challenge current assumptions regarding key attributes of the functional gut microbiome, in particular with respect to its variability. We further argue that the closing of existing gaps in functional knowledge should be addressed by a most-wanted gene list, the development and application of molecular and cellular high-throughput measurements, the development and sensible use of experimental models, as well as the direct study of observable molecular effects in the human host. Copyright © 2017 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khodjamirian, Alexander; Mannel, Thomas; Petrov, Alexey A.

In this paper, we propose a novel method to study flavor-changing neutral currents in the e + e - → D * 0 and e + e -→ B s * transitions, tuning the energy of e + e -- collisions to the mass of the narrow vector resonance D * 0 or B s * . We present a thorough study of both short-distance and long-distance contributions to e + e - → D * 0 in the Standard Model and investigate possible contributions of new physics in the charm sector. This process, albeit very rare, has clear advantagesmore » with respect to the D 0 → e + e - decay: the helicity suppression is absent, and a richer set of effective operators can be probed. Finally, implications of the same proposal for B s * are also discussed.« less

How do medical student journals fare? A global survey of journals run by medical students.

PubMed

Alamri, Yassar

2016-01-01

Medical students have made significant contributions to the medical and scientific fields in the past. Today, medical students still contribute to biomedical research; however, they often face disappointment from journals when trying to publish their findings. This led to the development of medical student journals, which take a more "student-friendly" approach. This article reviews the current medical student journals published in English and sheds light on current trends and challenges.

Characteristics of plasma ring, surrounding the Earth at geocentric distances ˜7-10RE, and magnetospheric current systems

NASA Astrophysics Data System (ADS)

Antonova, E. E.; Kirpichev, I. P.; Vovchenko, V. V.; Stepanova, M. V.; Riazantseva, M. O.; Pulinets, M. S.; Ovchinnikov, I. L.; Znatkova, S. S.

2013-07-01

There are strong experimental evidences of the existence of plasma domain forming a closed plasma ring around the Earth at geocentric distances ∼7-10RE. In this work, we analyze the main properties of this ring, using the data of the THEMIS satellite mission, acquired between April 2007 and September 2011. We also analyze the contribution of this ring to the storm dynamics. In particular, it is shown that the distribution of plasma pressure at ∼7-10RE is nearly azimuthally symmetric. However, the daytime compression of the magnetic field lines and the shift of the minimal value of the magnetic field to higher latitudes lead to the spreading of the transverse current along field lines and splitting of the daytime integral transverse current into two branches in Z direction. The CRC is the high latitude continuation of the ordinary ring current (RC), generated by plasma pressure gradients, directed to the Earth. We evaluated the contribution of the azimuthally symmetric part of the plasma ring to the Dst index for strong geomagnetic storms using the AMPTE/CCE radial profiles of plasma pressure published before, and showed that the contribution of the ring current including both RC and CRC is sufficient to obtain the observed Dst variation without the necessity to include the tail current system.

Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation.

PubMed

Glasscock, Edward; Voigt, Niels; McCauley, Mark D; Sun, Qiang; Li, Na; Chiang, David Y; Zhou, Xiao-Bo; Molina, Cristina E; Thomas, Dierk; Schmidt, Constanze; Skapura, Darlene G; Noebels, Jeffrey L; Dobrev, Dobromir; Wehrens, Xander H T

2015-09-01

Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson's trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility.

Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation

PubMed Central

Glasscock, Edward; Voigt, Niels; McCauley, Mark D.; Sun, Qiang; Li, Na; Chiang, David Y.; Zhou, Xiao-Bo; Molina, Cristina E.; Thomas, Dierk; Schmidt, Constanze; Skapura, Darlene G.; Noebels, Jeffrey L.; Dobrev, Dobromir; Wehrens, Xander H. T.

2016-01-01

Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson’s trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility. PMID:26162324

Boosting mediated electron transfer in bioelectrochemical systems with tailored defined microbial cocultures.

PubMed

Schmitz, Simone; Rosenbaum, Miriam A

2018-05-19

Bioelectrochemical systems (BES) hold great promise for sustainable energy generation via a microbial catalyst from organic matter, for example, from wastewater. To improve current generation in BES, understanding the underlying microbiology of the electrode community is essential. Electron mediator producing microorganism like Pseudomonas aeruginosa play an essential role in efficient electricity generation in BES. These microbes enable even nonelectroactive microorganism like Enterobacter aerogenes to contribute to current production. Together they form a synergistic coculture, where both contribute to community welfare. To use microbial co-operation in BES, the physical and chemical environments provided in the natural habitats of the coculture play a crucial role. Here, we show that synergistic effects in defined cocultures of P. aeruginosa and E. aerogenes can be strongly enhanced toward high current production by adapting process parameters, like pH, temperature, oxygen demand, and substrate requirements. Especially, oxygen was identified as a major factor influencing coculture behavior and optimization of its supply could enhance electric current production over 400%. Furthermore, operating the coculture in fed-batch mode enabled us to obtain very high current densities and to harvest electrical energy for 1 month. In this optimized condition, the coulombic efficiency of the process was boosted to 20%, which is outstanding for mediator-based electron transfer. This study lays the foundation for a rationally designed utilization of cocultures in BES for bioenergy generation from specific wastewaters or for bioprocess sensing and for benefiting from their synergistic effects under controlled bioprocess condition. © 2018 Wiley Periodicals, Inc.

MHD Stability in Compact Stellarators

NASA Astrophysics Data System (ADS)

Fu, Guoyong

1999-11-01

A key issue for current carrying compact stellarators(S.P. Hirshman et al., "Physics of compact stellarators", Phys. Plasmas 6, 1858 (1999).) is the stability of ideal MHD modes. We present recent stability results of external kink modes, ballooning mode, and vertical modes in Quasi-axisymmetric Stellarators (QAS)( A. Reiman et al, "Physics issue in the design of a high beta Quasi-Axisymmetric Stellarator" the 17th IAEA Fusion Energy conference, (Yokohama, Japan, October 1998), Paper ICP/06.) as well as Quasi-Omnigeneous Stellarators (QOS)^2. The 3D stability code Terpsichore(W. A. Cooper et al., Phys. Plasmas 3, 275 (1996)) is used in this study. The vertical stability in a current carrying stellarator is studied for the first time. The vertical mode is found to be stabilized by externally generated poloidal flux(G.Y. Fu et al., "Stability of vertical mode in a current carrying stellarator"., to be submitted). Physically, this is because the external poloidal flux enhances the field line bending energy relative to the current drive term in the MHD energy principle, δ W. A simple stability criteria is derived in the limit of large aspect ratio and constant current density. For wall at infinite distance from the plasma, the amount of external flux needed for stabilization is given by f=(κ^2-κ)/(κ^2+1) where κ is the axisymmetric elongation and f is the fraction of the external rotational transform at the plasma edge. A systematic parameter study shows that the external kink in QAS can be stabilized at high beta ( ~ 5%) without a conducting wall by combination of edge magnetic shear and 3D shaping(G. Y. Fu et al., "MHD stability calculations of high-beta Quasi-Axisymmetric Stellarators", the 17th IAEA Fusion Energy conference, (Yokohama, Japan, October 1998), paper THP1/07.). The optimal shaping is obtained by using an optimizer with kink stability included in its objective function. The physics mechanism for the kink modes is studied by examining relative contributions of individual terms in δ W. It is found the external kinks are mainly driven by the parallel current. The pressure contributes significantly to the overall drive through the curvature term and the Pfirsch-Schluter current. These results demonstrate potential of QAS and QOS for disruption-free operations at high-beta without a close-fitting conducting wall and feedback stabilization.

Current status and perspectives of the development of dental research in biological anthropology of Argentina: introduction and conclusions of the symposium.

PubMed

Luna, Leandro H; Bernal, Valeria

2011-10-01

This paper describes and discusses the research in the field of dental anthropology in Argentina. It has been presented at the symposium entitled "The development of dental research in Argentine Biological Anthropology: current status and perspectives", coordinated by the authors at the IX National Meeting of Biological Anthropology of Argentina, Puerto Madryn, 20th-23rd October 2009. The aim of the symposium was to present new results and future prospects of this discipline in the country and to create a forum for discussion of current research within this field. Six contributions that focused on the study of teeth from different perspectives and analysed bioarchaeological samples from different areas of Argentina (Central Highlands, Pampa and Patagonia) were presented. After the presentations, a discussion about the state of the art of dental research in the country was generated, in which the need for the generation of methodological consensus on the criteria for the evaluation of the variables considered was stated, so that research conducted in different areas can be compared. In short, the contributions of this symposium provide insights into the diversity of dental anthropology in contemporary Argentina and the potential of these types of studies to gain important information about biological and cultural aspects of the native populations in the country. Copyright © 2011 Elsevier GmbH. All rights reserved.

Multispacecraft Observations and 3D Structure of Electromagnetic Electron Phase-Space Holes

NASA Astrophysics Data System (ADS)

Holmes, J.; Ahmadi, N.; Ergun, R.; Wilder, F. D.; Newman, D. L.; Le Contel, O.; Torbert, R. B.; Burch, J. L.

2017-12-01

Electron phase-space holes are nonlinear plasma structures characterized by a unipolar trapping potential with a radial electric field. They commonly form from beam instabilities and other turbulent processes in many plasma environments. Due to their strong fields and long lifetimes, it has been hypothesized that phase-space holes can carry energy over long distances, contribute to large-scale currents, and accelerate individual particles to high energies. With electromagnetic field measurements at high cadence and precision on more than two spacecraft, we can compare the real 3D structure of electron phase-space holes to the models suggested by Andersson et al. (2009) and Treumann and Baumjohann (2012). In this case study, we consider a train of correlated electron phase-space holes observed by all four MMS spacecraft on the dusk flank within the magnetosphere. A number of the holes appear to pass directly through the 7 km tetrahedron formation. We use this data to compute the holes' phase velocity vector relative to the background magnetic field, and quantify their internal currents and associated magnetic moments. For these weak magnetic signatures, we find that the contribution from internal E×B0 currents is comparable to the v×E effect. This study will be interesting to compare with MMS observations in the magnetotail, which are expected to capture large, semi-relativistic phase-space holes with a strong magnetic component.

Observing mass exchange with the Lofoten Basin using surface drifters

NASA Astrophysics Data System (ADS)

Dugstad, Johannes S.; LaCasce, Joe; Koszalka, Inga M.; Fer, Ilker

2017-04-01

The Lofoten Basin in the Nordic Seas plays a central role in the global overturning circulation, acting as a reservoir for northward-flowing Atlantic water. Substantial heat loss occurs here, permitting the waters to become denser and eventually sink nearer the Arctic. Idealized modeling studies and theoretical arguments suggest the warm water enters the Lofoten Basin via eddy transport from the boundary current over the adjacent continental slope. But there is no observational evidence that this is the major contribution to mass exchange between the warm Atlantic Current and the Basin. How the basin waters exit also remains a mystery. Surface drifters offer an unique possibility to study the pathways of the boundary-basin exchange of mass and heat. We thereby examine trajectories of surface drifters released in the Nordic Seas in the POLEWARD and PROVOLO experiments, and supplemented by historical data from the Global Drifter Array. Contrary to the idea that the boundary current eddies are the main source, the results suggest that fluid is entering the Lofoten Basin from all sides. However, the drifters exit preferentially in the northeast corner of the basin. This asymmetry likely contributes to the extended residence times of the warm Atlantic waters in the Lofoten Basin. We consider various measures to quantify the effect, and test whether this is captured in a high resolution numerical model.

Electron Jet Detected by MMS at Dipolarization Front

NASA Astrophysics Data System (ADS)

Liu, C. M.; Fu, H. S.; Vaivads, A.; Khotyaintsev, Y. V.; Gershman, D. J.; Hwang, K.-J.; Chen, Z. Z.; Cao, D.; Xu, Y.; Yang, J.; Peng, F. Z.; Huang, S. Y.; Burch, J. L.; Giles, B. L.; Ergun, R. E.; Russell, C. T.; Lindqvist, P.-A.; Le Contel, O.

2018-01-01

Using MMS high-resolution measurements, we present the first observation of fast electron jet (Ve 2,000 km/s) at a dipolarization front (DF) in the magnetotail plasma sheet. This jet, with scale comparable to the DF thickness ( 0.9 di), is primarily in the tangential plane to the DF current sheet and mainly undergoes the E × B drift motion; it contributes significantly to the current system at the DF, including a localized ring-current that can modify the DF topology. Associated with this fast jet, we observed a persistent normal electric field, strong lower hybrid drift waves, and strong energy conversion at the DF. Such strong energy conversion is primarily attributed to the electron-jet-driven current (E ṡ je ≈ 2 E ṡ ji), rather than the ion current suggested in previous studies.

Line-of-sight magnetic flux imbalances caused by electric currents

NASA Technical Reports Server (NTRS)

Gary, G. Allen; Rabin, Douglas

1995-01-01

Several physical and observational effects contribute to the significant imbalances of magnetic flux that are often observed in active regions. We consider an effect not previously treated: the influence of electric currents in the photosphere. Electric currents can cause a line-of-sight flux imbalance because of the directionality of the magnetic field they produce. Currents associated with magnetic flux tubes produce larger imbalances than do smoothly-varying distributions of flux and current. We estimate the magnitude of this effect for current densities, total currents, and magnetic geometry consistent with observations. The expected imbalances lie approximately in the range 0-15%, depending on the character of the current-carying fields and the angle from which they are viewed. Observationally, current-induced flux imbalances could be indicated by a statistical dependence of the imbalance on angular distance from disk center. A general study of magnetic flux balance in active regions is needed to determine the relative importance of other- probably larger- effects such as dilute flux (too weak to measure or rendered invisible by radiative transfer effects), merging with weak background fields, and long-range connections between active regions.

An Exploratory Survey of Four Groups of 1987 Graduating Seniors' Perceptions Pertaining to (1) the Qualities of a Good Citizen, (2) the Sources of Citizenship Influence, and (3) the Contributions of Social Studies Courses and Programs of Study to Citizenship Development.

ERIC Educational Resources Information Center

Dynneson, Thomas L.; And Others

As a means of investigating the current status of citizenship education in the schools, this exploratory study was designed to study graduating high school seniors' perceptions of their citizenship experiences. A questionnaire was distributed to four schools in Texas, Minnesota, California, and Arkansas and data were analyzed using Boos's…

Societal and Familial Supports in the Development of Feminists.

ERIC Educational Resources Information Center

Acker, Joan; Howard, Mary

The research presented in this study examines who feminists are and what kinds of life experiences may have contributed to the process of becoming a feminist. A discussion of the barriers to the emergence of a women's movement and a reconsideration of some current explanations of the emergence of a movement at this particular historical moment…

Canadian Portrait of Changes in Family Structure and Preschool Children's Behavioral Outcomes

ERIC Educational Resources Information Center

Gosselin, Julie; Romano, Elisa; Bell, Tessa; Babchishin, Lyzon; Hudon-ven der Buhs, Isabelle; Gagné, Annie; Gosselin, Natasha

2014-01-01

Whereas US-based data have contributed to our understanding of family composition changes over the last decades, data on Canadian families are limited, and previous studies have stressed the need for in depth, longitudinal investigations. This article begins to fill this gap in the literature by providing a current and detailed portrait of family…

A Picture of Burnout: Case Studies and Solutions Toward Improving Radiologists' Well-being.

PubMed

Restauri, Nicole; Flug, Jonathan A; Mcarthur, Tatum A

This article uses case fictional case vignettes as a vehicle to discuss the complex way organizational and individual factors contribute to physician burnout. The article incorporates a review of the current literature on physician burnout focusing on work place inefficiency and ineffective leadership. Copyright © 2017 Elsevier Inc. All rights reserved.

Administrators' Perceptions of Motives to Offer Online Academic Degree Programs in Universities

ERIC Educational Resources Information Center

Özcan, Hakan; Yildirim, Soner

2018-01-01

Although the number of online academic degree programs offered by universities in Turkey has become increasingly significant in recent years, the current lack of understanding of administrators' motives that contribute to initiating these programs suggests there is much to be learned in this field. This study aimed to investigate administrators'…

What Makes a Caseload (Un) Manageable? School-Based Speech-Language Pathologists Speak

ERIC Educational Resources Information Center

Katz, Lauren A.; Maag, Abby; Fallon, Karen A.; Blenkarn, Katie; Smith, Megan K.

2010-01-01

Purpose: Large caseload sizes and a shortage of speech-language pathologists (SLPs) are ongoing concerns in the field of speech and language. This study was conducted to identify current mean caseload size for school-based SLPs, a threshold at which caseload size begins to be perceived as unmanageable, and variables contributing to school-based…

The Effects of Age and Sublexical Automaticity on Reading Outcomes for Students with Reading Disabilities

ERIC Educational Resources Information Center

Metsala, Jamie L.; David, Margaret D.

2017-01-01

For students with reading disabilities, reading fluency has proven difficult to remediate. The current study examined age-related effects on measures of word and text-reading outcomes, within the context of a phonologically based remedial reading program. The contribution of speeded-reading of sublexical sound-spelling patterns to fluency outcomes…

Hydrologic behavior of gullies in the South Carolina piedmont

Treesearch

M.A. Galang; C.R. Jackson; L.A. Morris; D. Markewitz; E.A. Carter

2007-01-01

The Piedmont region in the United States has been eroded and gullied due to deforestation and cultivation during the 1700 and 1800. Currently, a majority of these gullies are under forest vegetation and appear stable; however, neither the hydrology of these gullies, nor their sediment contribution to surface waters, has been quantified. This study instrumented eight...

Adjunct Experiences with and Perceptions of Professional Development at a Texas Community College

ERIC Educational Resources Information Center

Miles, R. Mark

2017-01-01

Universities and colleges have developed an over-reliance on adjunct faculty, and as a result, researchers have begun to study adjunct faculty satisfaction as it relates to their working conditions. Current research indicates that professional development is a source that can contribute to satisfaction at work (Hoyt, 2012). However, the research…

Mhealth on Campus: Assessing Undergraduates' Attitudes and Utilization of Mobile Health Applications

ERIC Educational Resources Information Center

Haithcox-Dennis, Melissa; Brinkley, Jason; Richman, Alice; DeWeese, Amanda; Byrd, James L., III

2012-01-01

Mhealth is rapidly becoming a valuable tool to increase knowledge and skills that contribute to healthy behaviors. Currently, little is known about college students' ownership and use of health apps. The primary purpose of this study was to investigate undergraduates' mhealth app usage and views. A secondary purpose was to identify any subgroup…

Infant Risk Factors Associated with Internalizing, Externalizing, and Co-Occurring Behavior Problems in Young Children

ERIC Educational Resources Information Center

Edwards, Renee C.; Hans, Sydney L.

2015-01-01

The purpose of the current study was to examine the unique and interactive contributions of infant negative emotionality and family risk factors in the development of internalizing-only, externalizing-only, and co-occurring behavior problems in early childhood. The sample included 412 infants and their primary caregivers. Interviews and…

Factors Contributing to the Retention of Natural Mentors among Underrepresented Students across the First Year of College

ERIC Educational Resources Information Center

Negrete, Andrea; Griffith, Aisha N.; Hurd, Noelle M.

2018-01-01

The current study examined characteristics of natural mentoring relationships (NMRs; i.e. mentoring relationships that develop organically with adults in one's pre-existing social network) among underrepresented college students as contributors to NMR retention across the first year of college. The sample consisted of 209 underrepresented college…

Implementing Educational Language Policy in Arizona: Legal, Historical and Current Practices in SEI

ERIC Educational Resources Information Center

Arias, M. Beatriz, Ed.; Faltis, Christian, Ed.

2012-01-01

This volume is a unique contribution to the study of language policy and education for English Learners because it focuses on the decade long implementation of "English Only" in Arizona. How this policy influences teacher preparation and classroom practice is the central topic of this volume. Scholars and researchers present their latest…

Contract Cheating in UK Higher Education: A Covert Investigation of Essay Mills

ERIC Educational Resources Information Center

Medway, Dominic; Roper, Stuart; Gillooly, Leah

2018-01-01

Contract cheating is currently a concern for universities and the higher education (HE) sector. It has been brought into the spotlight in recent years through the growth of online essay mills, where students can easily commission and purchase written assessment responses. This study contributes to the wider literature on academic integrity in HE…

Differentiating Challenge Reactivity from Psychomotor Activity in Studies of Children's Psychophysiology: Considerations for Theory and Measurement

ERIC Educational Resources Information Center

Bush, Nicole R.; Alkon, Abbey; Obradovic, Jelena; Stamperdahl, Juliet; Boyce, W. Thomas

2011-01-01

Current methods of assessing children's physiological "stress reactivity" may be confounded by psychomotor activity, biasing estimates of the relation between reactivity and health. We examined the joint and independent contributions of psychomotor activity and challenge reactivity during a protocol for 5- and 6-year-old children (N = 338).…

The paleoecology of fire and oaks in eastern forests

Treesearch

William A. III Patterson

2006-01-01

Oaks (Quercus spp.) currently dominate eastern deciduous forests, but are widely perceived as declining, with regeneration inadequate to perpetuate many stands. Most stands regenerated following fire in the 19th and early 20th centuries, and a lack of recent fire is viewed as contributing to the shortage of sapling and pole-size stands. But paleoecological studies...

A Cross-Cultural Comparison of Belgian and Vietnamese Children's Social Competence and Behavior

ERIC Educational Resources Information Center

Roskam, Isabelle; Hoang, Thi Vân; Schelstraete, Marie-Anne

2017-01-01

Children's social competence and behavioral adjustment are key issues for child development, education, and clinical research. Cross-cultural analyses are necessary to provide relevant methods of assessing them for cross-cultural research. The aim of the current study was to contribute to this important line of research by validating the 3-factor…

Development and Field Test of the Multiple Intelligences Learning Instruction Congruency Impact Scale

ERIC Educational Resources Information Center

Peifer, Nancy

2012-01-01

The purpose of this study was to contribute to the academic discussion regarding the validity of Multiple Intelligences (MI) theory through focusing on the validity of an important construct embedded in the theory, that of congruence between instructional style and preferred MI style for optimal learning. Currently there is insufficient empirical…