Cognition and Function in Language.

ERIC Educational Resources Information Center

Fox, Barbara A., Ed.; Jurafsky, Dan, Ed.; Michaelis, Laura A., Ed.

Selected papers include: "From Core to Periphery: A Study on the Directionality of Syntactic Change in Japanese" (Kaoru Horie); "On the Extension of Body-Part Nouns to Object-Part Nouns and Spatial Adpositions" (Yo Matsumoto); "Noun Classes: Language Change and Learning" (Maria Polinsky, Dan Jackson);…

The Public Positioning of Refugees in the Quasi-Education Market: Linking Mediascapes and Social Geographies of Schooling

ERIC Educational Resources Information Center

Windle, Joel

2017-01-01

This article analyses some ways in which racialising discourses around refugees interact with the spatial and social dynamics of marketised schooling. It identifies conflicting discourses that contribute to the polarisation of school social composition and resourcing in the Australian state of Victoria. Media narratives around "ethnic"…

Climate-driven endemic cholera is modulated by human mobility in a megacity

NASA Astrophysics Data System (ADS)

Perez-Saez, Javier; King, Aaron A.; Rinaldo, Andrea; Yunus, Mohammad; Faruque, Abu S. G.; Pascual, Mercedes

2017-10-01

Although a differential sensitivity of cholera dynamics to climate variability has been reported in the spatially heterogeneous megacity of Dhaka, Bangladesh, the specific patterns of spread of the resulting risk within the city remain unclear. We build on an established probabilistic spatial model to investigate the importance and role of human mobility in modulating spatial cholera transmission. Mobility fluxes were inferred using a straightforward and generalizable methodology that relies on mapping population density based on a high resolution urban footprint product, and a parameter-free human mobility model. In accordance with previous findings, we highlight the higher sensitivity to the El Niño Southern Oscillation (ENSO) in the highly populated urban center than in the more rural periphery. More significantly, our results show that cholera risk is largely transmitted from the climate-sensitive core to the periphery of the city, with implications for the planning of control efforts. In addition, including human mobility improves the outbreak prediction performance of the model with an 11 month lead. The interplay between climatic and human mobility factors in cholera transmission is discussed from the perspective of the rapid growth of megacities across the developing world.

Discourse Factors Influencing Spatial Descriptions in English and German

NASA Astrophysics Data System (ADS)

Vorwerg, Constanze; Tenbrink, Thora

The ways in which objects are referred to by using spatial language depend on many factors, including the spatial configuration and the discourse context. We present the results of a web experiment in which speakers were asked to either describe where a specified item was located in a picture containing several items, or which item was specified. Furthermore, conditions differed as to whether the first six configurations were specifically simple or specifically complex. Results show that speakers' spatial descriptions are more detailed if the question is where rather than which, mirroring the fact that contrasting the target item from the others in which tasks may not always require an equally detailed spatial description as in where tasks. Furthermore, speakers are influenced by the complexity of initial configurations in intricate ways: on the one hand, individual speakers tend to self-align with respect to their earlier linguistic strategies; however, also a contrast effect could be identified with respect to the usage of combined projective terms.

Abnormal center-periphery gradient in spatial attention in simultanagnosia.

PubMed

Balslev, Daniela; Odoj, Bartholomaeus; Rennig, Johannes; Karnath, Hans-Otto

2014-12-01

Patients suffering from simultanagnosia cannot perceive more than one object at a time. The underlying mechanism is incompletely understood. One hypothesis is that simultanagnosia reflects "tunnel vision," a constricted attention window around gaze, which precludes the grouping of individual objects. Although this idea has a long history in neuropsychology, the question whether the patients indeed have an abnormal attention gradient around the gaze has so far not been addressed. Here we tested this hypothesis in two simultanagnosia patients with bilateral parieto-occipital lesions and two control groups, with and without brain damage. We assessed the participants' ability to discriminate letters presented briefly at fixation with and without a peripheral distractor or in the visual periphery, with or without a foveal distractor. A constricted span of attention around gaze would predict an increased susceptibility to foveated versus peripheral distractors. Contrary to this prediction and unlike both control groups, the patients' ability to discriminate the target decreased more in the presence of peripheral compared with foveated distractors. Thus, the attentional spotlight in simultanagnosia does not fall on foveated objects as previously assumed, but rather abnormally highlights the periphery. Furthermore, we found the same center-periphery gradient in the patients' ability to recognize multiple objects. They detected multiple, but not single objects more accurately in the periphery than at fixation. These results suggest that an abnormal allocation of attention around the gaze can disrupt the grouping of individual objects into an integrated visual scene.

Monitoring the transformation of Yogyakarta’s urban form using remote sensing and Geographic Information System

NASA Astrophysics Data System (ADS)

Rozano, B.; Yan, W.

2018-04-01

Urban form transformation can be seen as the results of urbanization spatially, where the land changed into an urbanized one. Monitoring its changes, however, require many human and financial resources. Accordingly, this research aims to identify urban form transformation using GIS/remote sensing and its spatial implications to the peri-urban area. In order to analyze the land cover changes, this research uses multispectral images from 1990-2016 for built-up extraction using New Built Up Index (NBUI) analysis and population data 1996-2015 combined with primary data from the respondents and key informants. Based on the analysis, it is seen that the compacted Yogyakarta Urban Area scattered predominantly to the Northern part of its periphery with the increase of urban area from 21.19% in 1990 to 50.91% in 2017. While this urbanization is an on-going process, the population of urban core showed a de-concentration phenomenon in 2015, spreading to its periphery causing some negative implications to the peri-urban area.

Spacing conservation practice: Place-making, social learning, and adaptive governance in natural resource management [Chapter 15

Treesearch

Daniel R. Williams

2018-01-01

Nature conservation constitutes an important realm of professional practice with strong connections to the discourses on nature and sustainability. In recent decades much of that discourse has taken an explicitly spatial turn, observable across numerous domains of ecological, social, and political thought (Williams et al., 2013; Wu, 2006). The aim of this chapter is to...

The marginalisation of dreams in clinical psychological practice.

PubMed

Leonard, Linda; Dawson, Drew

2018-04-22

The longstanding human interest in dreams has led to a significant body of psychological and philosophical discourse, including research. Recently, however, dreams have been relegated to the periphery of clinical psychological practice. This is potentially problematic as clients continue to bring dreams to therapy and many psychologists lack the confidence or competence to respond effectively to dream material. Building on the structural, professional and research cultures surrounding psychology using a cultural-historical activity theory framework, we argue the marginalisation of dreams is due to cultural-historical factors. These factors include the political and economic context in which psychology developed; psychology's early attempts to differentiate from psychoanalysis by identifying with behaviourism and the natural sciences; and a discipline-specific definition of what constitutes evidence-based practice. These factors led to professional discourses within which dreams are seen as of little clinical or therapeutic value, or that dream work is only for long-term therapy and requires extensive therapist training. However, there are diverse models of dream work consistent with most theoretical orientations within contemporary psychological practice. We conclude with recommendations on how to rebuild clinical confidence and competence in the use of dream material within the current professional environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Interactions between the spatial and temporal stimulus factors that influence multisensory integration in human performance.

PubMed

Stevenson, Ryan A; Fister, Juliane Krueger; Barnett, Zachary P; Nidiffer, Aaron R; Wallace, Mark T

2012-05-01

In natural environments, human sensory systems work in a coordinated and integrated manner to perceive and respond to external events. Previous research has shown that the spatial and temporal relationships of sensory signals are paramount in determining how information is integrated across sensory modalities, but in ecologically plausible settings, these factors are not independent. In the current study, we provide a novel exploration of the impact on behavioral performance for systematic manipulations of the spatial location and temporal synchrony of a visual-auditory stimulus pair. Simple auditory and visual stimuli were presented across a range of spatial locations and stimulus onset asynchronies (SOAs), and participants performed both a spatial localization and simultaneity judgment task. Response times in localizing paired visual-auditory stimuli were slower in the periphery and at larger SOAs, but most importantly, an interaction was found between the two factors, in which the effect of SOA was greater in peripheral as opposed to central locations. Simultaneity judgments also revealed a novel interaction between space and time: individuals were more likely to judge stimuli as synchronous when occurring in the periphery at large SOAs. The results of this study provide novel insights into (a) how the speed of spatial localization of an audiovisual stimulus is affected by location and temporal coincidence and the interaction between these two factors and (b) how the location of a multisensory stimulus impacts judgments concerning the temporal relationship of the paired stimuli. These findings provide strong evidence for a complex interdependency between spatial location and temporal structure in determining the ultimate behavioral and perceptual outcome associated with a paired multisensory (i.e., visual-auditory) stimulus.

Inferring geographic isolation of wolverines in California using historical DNA

Treesearch

Michael K. Schwartz; Keith B. Aubry; Kevin S. McKelvey; Kristine L. Pilgrim; Jeffrey P. Copeland; John R. Squires; Robert M. Inman; Samantha M. Wisely; Leonard F. Ruggiero

2007-01-01

Delineating a species' geographic range using the spatial distribution of museum specimens or even contemporary detection-non-detection data can be difficult. This is particularly true at the periphery of a species range where species' distributions are often disjunct. Wolverines (Gulo gulo) are wide-ranging mammals with discontinuous and...

An explanation of the formation of the peculiar periphery of Tycho's supernova remnant

NASA Astrophysics Data System (ADS)

Fang, Jun; Yu, Huan; Zhang, Li

2018-02-01

Tycho's supernova remnant (SNR) has a periphery that clearly deviates from a spherical shape, based on X-ray and radio observations. The forward shock from the south-east to the north of the remnant has a deformed outline with a depression in the east, although in the west it is generally round and smooth. Moreover, at some locations in the shell, the supernova ejecta is located close to the forward shock, resulting in protrusions. Using 3D hydrodynamical simulations, we studied the dynamical evolution of the supernova ejecta in an inhomogeneous medium and the formation process of the profile of the forward shock. In order to reproduce the peculiar periphery of the remnant, we propose a model in which the supernova ejecta has evolved in a cavity blown by a latitude-dependent outflow. The results indicate that the depression to the east and the protrusion to the south-east on the observed periphery of the remnant can be generally reproduced if we assume a wind bubble driven by an anisotropic wind with a mass-loss rate of ˜10-7 M⊙ yr-1, a pole velocity of ˜100 km s-1, a duration of ˜105 yr prior to the supernova explosion, and a spatial velocity of ˜30 km s-1 of the progenitor with respect to the circumstellar medium. In conclusion, an explanation of the peculiar shape of the periphery of Tycho's SNR is that the supernova ejecta evolved in the cavity driven by a latitude-dependent wind.

Medication communication during ward rounds on medical wards: Power relations and spatial practices.

PubMed

Liu, Wei; Manias, Elizabeth; Gerdtz, Marie

2013-03-01

Communication plays a crucial role in the management of medications. Ward rounds are sites where health professionals from different disciplines and patients come together to exchange medication information and make treatment decisions. This article examines power relations and spatial practices surrounding medication communication between patients and health professionals including doctors, nurses and pharmacists during ward rounds. Data were collected in two medical wards of a metropolitan teaching hospital in Melbourne, Australia. Data collection methods involved participant observations, field interviews, video-recordings, together with individual and group reflexive interviews. A critical discourse analysis was undertaken to identify the location sites where power relations were reproduced or challenged in ward rounds. Findings demonstrated that traditional medical hierarchies constructed the ways in which doctors communicated about medications during ward rounds. Nurses and pharmacists ventured into the ward round space by using the discourse of preparation and occupying a peripheral physical position. Doctors privileged the discourse of medication rationalization in their ward round discussions, competing with the discourse of inquiry taken up by patients and families. Ward rounds need to be restructured to provide opportunities for nurses and pharmacists to speak at dedicated times and in strategic locations. By critically reflecting upon the complex process of medication communication during ward rounds, greater opportunities exist for enhanced team communication among health professionals.

The crowding factor method applied to parafoveal vision

PubMed Central

Ghahghaei, Saeideh; Walker, Laura

2016-01-01

Crowding increases with eccentricity and is most readily observed in the periphery. During natural, active vision, however, central vision plays an important role. Measures of critical distance to estimate crowding are difficult in central vision, as these distances are small. Any overlap of flankers with the target may create an overlay masking confound. The crowding factor method avoids this issue by simultaneously modulating target size and flanker distance and using a ratio to compare crowded to uncrowded conditions. This method was developed and applied in the periphery (Petrov & Meleshkevich, 2011b). In this work, we apply the method to characterize crowding in parafoveal vision (<3.5 visual degrees) with spatial uncertainty. We find that eccentricity and hemifield have less impact on crowding than in the periphery, yet radial/tangential asymmetries are clearly preserved. There are considerable idiosyncratic differences observed between participants. The crowding factor method provides a powerful tool for examining crowding in central and peripheral vision, which will be useful in future studies that seek to understand visual processing under natural, active viewing conditions. PMID:27690170

A combination of spatial and recursive temporal filtering for noise reduction when using region of interest (ROI) fluoroscopy for patient dose reduction in image guided vascular interventions with significant anatomical motion

NASA Astrophysics Data System (ADS)

Setlur Nagesh, S. V.; Khobragade, P.; Ionita, C.; Bednarek, D. R.; Rudin, S.

2015-03-01

Because x-ray based image-guided vascular interventions are minimally invasive they are currently the most preferred method of treating disorders such as stroke, arterial stenosis, and aneurysms; however, the x-ray exposure to the patient during long image-guided interventional procedures could cause harmful effects such as cancer in the long run and even tissue damage in the short term. ROI fluoroscopy reduces patient dose by differentially attenuating the incident x-rays outside the region-of-interest. To reduce the noise in the dose-reduced regions previously recursive temporal filtering was successfully demonstrated for neurovascular interventions. However, in cardiac interventions, anatomical motion is significant and excessive recursive filtering could cause blur. In this work the effects of three noise-reduction schemes, including recursive temporal filtering, spatial mean filtering, and a combination of spatial and recursive temporal filtering, were investigated in a simulated ROI dose-reduced cardiac intervention. First a model to simulate the aortic arch and its movement was built. A coronary stent was used to simulate a bioprosthetic valve used in TAVR procedures and was deployed under dose-reduced ROI fluoroscopy during the simulated heart motion. The images were then retrospectively processed for noise reduction in the periphery, using recursive temporal filtering, spatial filtering and a combination of both. Quantitative metrics for all three noise reduction schemes are calculated and are presented as results. From these it can be concluded that with significant anatomical motion, a combination of spatial and recursive temporal filtering scheme is best suited for reducing the excess quantum noise in the periphery. This new noise-reduction technique in combination with ROI fluoroscopy has the potential for substantial patient-dose savings in cardiac interventions.

Limits, excesses and pleasures: practices and discourses of sex work in a Mexican rural community.

PubMed

Parrini, Rodrigo; Amuchástegui, Ana; Garibi, Cecilia

2017-10-01

In Tomatlán, a small city on the Mexican Pacific Coast there is a tolerance zone in which a group of sex workers, separated from the rest of the city by a garbage dump, offer their services to local men. The women present themselves materially and symbolically as agents of regulation with respect to male sexuality, itself constructed as overwhelming and insatiable, which, were it not for services provided by the sex workers, would threaten the family-based social order. Through in-depth interviews with 19 sex workers and 5 municipal officials, this paper discusses how the sex gender system results in a series of borders that are both geographical and subjective. Such borders have to do with periphery and control, body and intimacy, and the boundaries of animality.

Facilitation of contrast detection in near-peripheral vision.

PubMed

Giorgi, Robert G; Soong, Grace P; Woods, Russell L; Peli, Eli

2004-12-01

Foveal detection of a Gabor patch (target) is facilitated by collinear, displaced high-contrast flankers. Polat and Sagi reported that the same phenomenon occurred in the periphery, but no data were presented [Proc. Natl. Acad. Sci. 91 (1994) 1206]. Others have found no facilitation in a limited number of conditions tested. To resolve this apparent conflict, we measured lateral facilitation in the near-periphery using a range of stimulus parameters. We found facilitation for a range of target-flanker distances for peripheral eccentricities up to 6 degrees , but the magnitude of the effect was less than found in central vision. Facilitation varied across subjects and with spatial frequency. Flanker contrast had no effect over the range evaluated (10-80%). Equal facilitation was found for two global arrangements of the stimulus pattern. Facilitation was found using a temporal, but not a spatial two-alternative forced-choice paradigm, accounting for the different results among previous studies. This finding supports previous indications of the role of attention in altering such facilitation. The value of facilitation from lateral interactions for persons with central vision impairment, who have to shift their attention to a peripheral locus constantly, needs to be examined.

Spatial problem-solving in a wheel-shaped maze: quantitative and qualitative analyses of the behavioural changes following damage to the hippocampus in the rat.

PubMed

Buhot, M C; Chapuis, N; Scardigli, P; Herrmann, T

1991-07-01

The behaviour of sham-operated rats and rats with damage to the dorsal hippocampus was compared in a complex spatial problem-solving task using a 'hub-spoke-rim' wheel type maze. Compared to the classical Olton 8-arm radial maze and Morris water maze, this apparatus presents the animal with a series of possible alternative routes both direct and indirect to the goal (food). The task included 3 main stages: exploration, feeding and testing, as do the classic problem-solving tasks. During exploration, hippocampal rats were found to be more active than sham rats. Nevertheless, they displayed habituation and a relatively efficient circumnavigation, though, in both cases, different from those of sham rats. During test trials, hippocampal rats were characterized as being less accurate, making more errors than sham rats. Nevertheless, both groups increased their accuracy of first choices over trials. The qualitative analyses of test trial performance indicated that hippocampal rats were less accurate in terms of the initial error's deviation from the goal, and less efficient in terms of corrective behaviour than sham rats which used either the periphery or the spokes to attain economically the goal. Surprisingly, hippocampal rats were not limited to a taxon type orientation but learned to use the periphery, a tendency which developed over time. Seemingly, for sham rats, the problem-solving process took the form of updating information during transit. For hippocampal rats, the use of periphery reflected both an ability to discriminate its usefulness in reaching the goal via a taxis type behaviour, and some sparing of ability to generalize the closeness and the location of the goal. These results, especially the strategic correction patterns, are discussed in the light of Sutherland and Rudy's 'configurational association theory'.

Selective spatial enhancement: Attentional spotlight size impacts spatial but not temporal perception.

PubMed

Goodhew, Stephanie C; Shen, Elizabeth; Edwards, Mark

2016-08-01

An important but often neglected aspect of attention is how changes in the attentional spotlight size impact perception. The zoom-lens model predicts that a small ("focal") attentional spotlight enhances all aspects of perception relative to a larger ("diffuse" spotlight). However, based on the physiological properties of the two major classes of visual cells (magnocellular and parvocellular neurons) we predicted trade-offs in spatial and temporal acuity as a function of spotlight size. Contrary to both of these accounts, however, across two experiments we found that attentional spotlight size affected spatial acuity, such that spatial acuity was enhanced for a focal relative to a diffuse spotlight, whereas the same modulations in spotlight size had no impact on temporal acuity. This likely reflects the function of attention: to induce the high spatial resolution of the fovea in periphery, where spatial resolution is poor but temporal resolution is good. It is adaptive, therefore, for the attentional spotlight to enhance spatial acuity, whereas enhancing temporal acuity does not confer the same benefit.

Detection of nanoparticles in carbon arc discharge with laser-induced incandescence

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

Yatom, S.; Bak, J.; Khrabryi, A.

Laser-induced incandescence measurements were conducted in the carbon arc discharge, used for synthesis of carbon nanostructures. The results reveal two spatial regions occupied by dominant populations of carbon particles with different sizes. Close to the axis of the arc, large micron size particles dominate the incandescence signal. In the arc periphery, the dominant population of nanoparticles has diameter of 20 nm. Using a heat transfer model between the gas, arc plasma and the particles, it is shown that such a drastic difference in the particle sizes can be explained by evaporation of the micron-scale particles which move across the arcmore » plasma towards the arc periphery. It is also hypothesized that mass evaporated from the micro particles contributes to the carbon feedstock for the formation of nanostructures. (C) 2017 Elsevier Ltd. All rights reserved.« less

Detection of nanoparticles in carbon arc discharge with laser-induced incandescence

DOE PAGES

Yatom, S.; Bak, J.; Khrabryi, A.; ...

2017-02-20

Laser-induced incandescence measurements were conducted in the carbon arc discharge, used for synthesis of carbon nanostructures. The results reveal two spatial regions occupied by dominant populations of carbon particles with different sizes. Close to the axis of the arc, large micron size particles dominate the incandescence signal. In the arc periphery, the dominant population of nanoparticles has diameter of 20 nm. Using a heat transfer model between the gas, arc plasma and the particles, it is shown that such a drastic difference in the particle sizes can be explained by evaporation of the micron-scale particles which move across the arcmore » plasma towards the arc periphery. It is also hypothesized that mass evaporated from the micro particles contributes to the carbon feedstock for the formation of nanostructures. (C) 2017 Elsevier Ltd. All rights reserved.« less

Transitions between central and peripheral vision create spatial/temporal distortions: a hypothesis concerning the perceived break of the curveball.

PubMed

Shapiro, Arthur; Lu, Zhong-Lin; Huang, Chang-Bing; Knight, Emily; Ennis, Robert

2010-10-13

The human visual system does not treat all parts of an image equally: the central segments of an image, which fall on the fovea, are processed with a higher resolution than the segments that fall in the visual periphery. Even though the differences between foveal and peripheral resolution are large, these differences do not usually disrupt our perception of seamless visual space. Here we examine a motion stimulus in which the shift from foveal to peripheral viewing creates a dramatic spatial/temporal discontinuity. The stimulus consists of a descending disk (global motion) with an internal moving grating (local motion). When observers view the disk centrally, they perceive both global and local motion (i.e., observers see the disk's vertical descent and the internal spinning). When observers view the disk peripherally, the internal portion appears stationary, and the disk appears to descend at an angle. The angle of perceived descent increases as the observer views the stimulus from further in the periphery. We examine the first- and second-order information content in the display with the use of a three-dimensional Fourier analysis and show how our results can be used to describe perceived spatial/temporal discontinuities in real-world situations. The perceived shift of the disk's direction in the periphery is consistent with a model in which foveal processing separates first- and second-order motion information while peripheral processing integrates first- and second-order motion information. We argue that the perceived distortion may influence real-world visual observations. To this end, we present a hypothesis and analysis of the perception of the curveball and rising fastball in the sport of baseball. The curveball is a physically measurable phenomenon: the imbalance of forces created by the ball's spin causes the ball to deviate from a straight line and to follow a smooth parabolic path. However, the curveball is also a perceptual puzzle because batters often report that the flight of the ball undergoes a dramatic and nearly discontinuous shift in position as the ball nears home plate. We suggest that the perception of a discontinuous shift in position results from differences between foveal and peripheral processing.

Development of a Bayesian Estimator for Audio-Visual Integration: A Neurocomputational Study

PubMed Central

Ursino, Mauro; Crisafulli, Andrea; di Pellegrino, Giuseppe; Magosso, Elisa; Cuppini, Cristiano

2017-01-01

The brain integrates information from different sensory modalities to generate a coherent and accurate percept of external events. Several experimental studies suggest that this integration follows the principle of Bayesian estimate. However, the neural mechanisms responsible for this behavior, and its development in a multisensory environment, are still insufficiently understood. We recently presented a neural network model of audio-visual integration (Neural Computation, 2017) to investigate how a Bayesian estimator can spontaneously develop from the statistics of external stimuli. Model assumes the presence of two unimodal areas (auditory and visual) topologically organized. Neurons in each area receive an input from the external environment, computed as the inner product of the sensory-specific stimulus and the receptive field synapses, and a cross-modal input from neurons of the other modality. Based on sensory experience, synapses were trained via Hebbian potentiation and a decay term. Aim of this work is to improve the previous model, including a more realistic distribution of visual stimuli: visual stimuli have a higher spatial accuracy at the central azimuthal coordinate and a lower accuracy at the periphery. Moreover, their prior probability is higher at the center, and decreases toward the periphery. Simulations show that, after training, the receptive fields of visual and auditory neurons shrink to reproduce the accuracy of the input (both at the center and at the periphery in the visual case), thus realizing the likelihood estimate of unimodal spatial position. Moreover, the preferred positions of visual neurons contract toward the center, thus encoding the prior probability of the visual input. Finally, a prior probability of the co-occurrence of audio-visual stimuli is encoded in the cross-modal synapses. The model is able to simulate the main properties of a Bayesian estimator and to reproduce behavioral data in all conditions examined. In particular, in unisensory conditions the visual estimates exhibit a bias toward the fovea, which increases with the level of noise. In cross modal conditions, the SD of the estimates decreases when using congruent audio-visual stimuli, and a ventriloquism effect becomes evident in case of spatially disparate stimuli. Moreover, the ventriloquism decreases with the eccentricity. PMID:29046631

Single-cell dynamics of genome-nuclear lamina interactions.

PubMed

Kind, Jop; Pagie, Ludo; Ortabozkoyun, Havva; Boyle, Shelagh; de Vries, Sandra S; Janssen, Hans; Amendola, Mario; Nolen, Leisha D; Bickmore, Wendy A; van Steensel, Bas

2013-03-28

The nuclear lamina (NL) interacts with hundreds of large genomic regions termed lamina associated domains (LADs). The dynamics of these interactions and the relation to epigenetic modifications are poorly understood. We visualized the fate of LADs in single cells using a "molecular contact memory" approach. In each nucleus, only ~30% of LADs are positioned at the periphery; these LADs are in intermittent molecular contact with the NL but remain constrained to the periphery. Upon mitosis, LAD positioning is not detectably inherited but instead is stochastically reshuffled. Contact of individual LADs with the NL is linked to transcriptional repression and H3K9 dimethylation in single cells. Furthermore, we identify the H3K9 methyltransferase G9a as a regulator of NL contacts. Collectively, these results highlight principles of the dynamic spatial architecture of chromosomes in relation to gene regulation. Copyright © 2013 Elsevier Inc. All rights reserved.

Rethinking the Bloody Code in Eighteenth-Century Britain: Capital Punishment at the Centre and on the Periphery

PubMed Central

King, Peter; Ward, Richard

2018-01-01

During the long eighteenth century the capital code, and more specifically the so-called ‘Bloody Code’ which subjected a vast and increasing range of property crimes to the death penalty, was the centre of much popular attention and of extensive debate. The impact of the Bloody Code has also attracted much attention from historians, some of whom have argued that it played a vital role both within the criminal law and in eighteenth-century social relations more generally. However, the geography of the Bloody Code and the possibility that there were major regional differences both in the use of hanging, and in attitudes to it, has been largely ignored by historians. By systematically exploring the spatial dimensions of capital punishment in eighteenth-century Britain, this article demonstrates the refusal of many areas on the periphery to implement the Bloody Code. The reluctance in the far western and northern periphery of Britain to execute property offenders, it is argued, requires us to rethink some of our core assumptions about the key role historians have given to the Bloody Code in maintaining the hegemony of the elite, about the process by which the capital code came to be reformed, and about the reach of the state in the long eighteenth century. PMID:29780182

Spline models of contemporary, 2030, 2060, and 2090 climates for Mexico and their use in understanding climate-change impacts on the vegetation

Treesearch

Cuauhtemoc Saenz-Romero; Gerald E. Rehfeldt; Nicholas L. Crookston; Pierre Duval; Remi St-Amant; Jean Beaulieu; Bryce A. Richardson

2010-01-01

Spatial climate models were developed for Mexico and its periphery (southern USA, Cuba, Belize and Guatemala) for monthly normals (1961-1990) of average, maximum and minimum temperature and precipitation using thin plate smoothing splines of ANUSPLIN software on ca. 3,800 observations. The fit of the model was generally good: the signal was considerably less than one-...

Quantitative analysis of nucleolar chromatin distribution in the complex convoluted nucleoli of Didinium nasutum (Ciliophora).

PubMed

Leonova, Olga G; Karajan, Bella P; Ivlev, Yuri F; Ivanova, Julia L; Skarlato, Sergei O; Popenko, Vladimir I

2013-01-01

We have earlier shown that the typical Didinium nasutum nucleolus is a complex convoluted branched domain, comprising a dense fibrillar component located at the periphery of the nucleolus and a granular component located in the central part. Here our main interest was to study quantitatively the spatial distribution of nucleolar chromatin structures in these convoluted nucleoli. There are no "classical" fibrillar centers in D.nasutum nucleoli. The spatial distribution of nucleolar chromatin bodies, which play the role of nucleolar organizers in the macronucleus of D.nasutum, was studied using 3D reconstructions based on serial ultrathin sections. The relative number of nucleolar chromatin bodies was determined in macronuclei of recently fed, starved D.nasutum cells and in resting cysts. This parameter is shown to correlate with the activity of the nucleolus. However, the relative number of nucleolar chromatin bodies in different regions of the same convoluted nucleolus is approximately the same. This finding suggests equal activity in different parts of the nucleolar domain and indicates the existence of some molecular mechanism enabling it to synchronize this activity in D. nasutum nucleoli. Our data show that D. nasutum nucleoli display bipartite structure. All nucleolar chromatin bodies are shown to be located outside of nucleoli, at the periphery of the fibrillar component.

The effects of display time and eccentricity on the detection of amplitude and phase degradations in textured stimuli.

PubMed

Clarke, Alasdair D F; Green, Patrick R; Chantler, Mike J

2012-03-08

The amplitude and phase spectra of an image contain important information for perception, and a large body of work has investigated the effects of manipulating these spectra on the recognition or classification of image content. Here, we use a novel means of investigating sensitivity to amplitude and phase spectra properties, testing the ability of observers to detect degradations of the spectral content of synthetic images of textured surfaces that are broadband in the frequency domain. The effects of display time and retinal eccentricity on sensitivity to these two manipulations are compared using stimuli matched for difficulty of detection. We find no difference between the time courses for the detection of degradation in the two spectra; in both cases, accuracy rises above chance when display times are greater than 80 ms. Increasing retinal eccentricity to 8.7°, however, has a significantly stronger effect on the accuracy of detecting degradations of the amplitude spectrum than of the phase spectrum. Further, sensitivity to phase randomization that is restricted to low spatial frequencies is greater in the periphery (at 8.7° eccentricity) than in the fovea. These last two results imply that the fovea and periphery are specialized for the processing of phase spectrum information in distinct spatial frequency bands.

Complementary therapies in rehabilitation: stroke patients' narratives. Part 2.

PubMed

van der Riet, Pamela; Dedkhard, Saowapa; Srithong, Kannapatch

2012-03-01

To document the narratives of nursing staff and patients in a Thailand Rehabilitation Centre where complementary therapies are used and to discuss perceived progress of these stroke patients. Specific complementary therapies used at this Rehabilitation Centre include Thai massage and herbal therapies. Whilst there has been a small amount of quantitative research on stroke patients and complementary therapies there has been no qualitative research on the experience of stroke patients and the use of complementary therapies. Qualitative pilot study using narrative inquiry and discourse analysis framed by poststructural theory. Six stroke patients were interviewed about their involvement in complementary therapy practice and treatments and their experiences of these therapies in rehabilitation. This study represents a reflective mining of patients' stories and captures the main theme of changes in stroke patients' embodiment and a main discourse of attending to and enabling progress. Throughout the storylines there are many other discourses such as hope, desire, helplessness, despair, fear, motivation, gratefulness, gladness and fragility. Threaded throughout the stroke patients' stories of their rehabilitation there is a layering of discourses involving tensions and a longing to overcome their disability. There are twists and detours in their stories that show the complexity of the illness experience. Progress is not straightforward with a quick recovery. Many contexts or variables influence progress such as spatiality, temporality and people. What is offered here is the reality of the rehabilitation process for stroke patients. Through the use of narrative inquiry the contexts of people, spatiality (environment) and temporality (time) are an important part of rehabilitation process. © 2011 Blackwell Publishing Ltd.

Retinal ganglion cells in the eastern newt Notophthalmus viridescens: topography, morphology, and diversity.

PubMed

Pushchin, Igor I; Karetin, Yuriy A

2009-10-20

The topography and morphology of retinal ganglion cells (RGCs) in the eastern newt were studied. Cells were retrogradely labeled with tetramethylrhodamine-conjugated dextran amines or horseradish peroxidase and examined in retinal wholemounts. Their total number was 18,025 +/- 3,602 (mean +/- SEM). The spatial density of RGCs varied from 2,100 cells/mm(2) in the retinal periphery to 4,500 cells/mm(2) in the dorsotemporal retina. No prominent retinal specializations were found. The spatial resolution estimated from the spatial density of RGCs varied from 1.4 cycles per degree in the periphery to 1.95 cycles per degree in the region of the peak RGC density. A sample of 68 cells was camera lucida drawn and subjected to quantitative analysis. A total of 21 parameters related to RGC morphology and stratification in the retina were estimated. Partitionings obtained by using different clustering algorithms combined with automatic variable weighting and dimensionality reduction techniques were compared, and an effective solution was found by using silhouette analysis. A total of seven clusters were identified and associated with potential cell types. Kruskal-Wallis ANOVA-on-Ranks with post hoc Mann-Whitney U tests showed significant pairwise between-cluster differences in one or more of the clustering variables. The average silhouette values of the clusters were reasonably high, ranging from 0.52 to 0.79. Cells assigned to the same cluster displayed similar morphology and stratification in the retina. The advantages and limitations of the methodology adopted are discussed. The present classification is compared with known morphological and physiological RGC classifications in other salamanders.

Attention Modifies Spatial Resolution According to Task Demands.

PubMed

Barbot, Antoine; Carrasco, Marisa

2017-03-01

How does visual attention affect spatial resolution? In texture-segmentation tasks, exogenous (involuntary) attention automatically increases resolution at the attended location, which improves performance where resolution is too low (at the periphery) but impairs performance where resolution is already too high (at central locations). Conversely, endogenous (voluntary) attention improves performance at all eccentricities, which suggests a more flexible mechanism. Here, using selective adaptation to spatial frequency, we investigated the mechanism by which endogenous attention benefits performance in resolution tasks. Participants detected a texture target that could appear at several eccentricities. Adapting to high or low spatial frequencies selectively affected performance in a manner consistent with changes in resolution. Moreover, adapting to high, but not low, frequencies mitigated the attentional benefit at central locations where resolution was too high; this shows that attention can improve performance by decreasing resolution. Altogether, our results indicate that endogenous attention benefits performance by modulating the contribution of high-frequency information in order to flexibly adjust spatial resolution according to task demands.

Biophysical, infrastructural and social heterogeneities explain spatial distribution of waterborne gastrointestinal disease burden in Mexico City

NASA Astrophysics Data System (ADS)

Baeza, Andrés; Estrada-Barón, Alejandra; Serrano-Candela, Fidel; Bojórquez, Luis A.; Eakin, Hallie; Escalante, Ana E.

2018-06-01

Due to unplanned growth, large extension and limited resources, most megacities in the developing world are vulnerable to hydrological hazards and infectious diseases caused by waterborne pathogens. Here we aim to elucidate the extent of the relation between the spatial heterogeneity of physical and socio-economic factors associated with hydrological hazards (flooding and scarcity) and the spatial distribution of gastrointestinal disease in Mexico City, a megacity with more than 8 million people. We applied spatial statistics and multivariate regression analyses to high resolution records of gastrointestinal diseases during two time frames (2007–2009 and 2010–2014). Results show a pattern of significant association between water flooding events and disease incidence in the city center (lowlands). We also found that in the periphery (highlands), higher incidence is generally associated with household infrastructure deficiency. Our findings suggest the need for integrated and spatially tailored interventions by public works and public health agencies, aimed to manage socio-hydrological vulnerability in Mexico City.

Attention Modifies Spatial Resolution According to Task Demands

PubMed Central

Barbot, Antoine; Carrasco, Marisa

2017-01-01

How does visual attention affect spatial resolution? In texture-segmentation tasks, exogenous (involuntary) attention automatically increases resolution at the attended location, which improves performance where resolution is too low (at the periphery) but impairs performance where resolution is already too high (at central locations). Conversely, endogenous (voluntary) attention improves performance at all eccentricities, which suggests a more flexible mechanism. Here, using selective adaptation to spatial frequency, we investigated the mechanism by which endogenous attention benefits performance in resolution tasks. Participants detected a texture target that could appear at several eccentricities. Adapting to high or low spatial frequencies selectively affected performance in a manner consistent with changes in resolution. Moreover, adapting to high, but not low, frequencies mitigated the attentional benefit at central locations where resolution was too high; this shows that attention can improve performance by decreasing resolution. Altogether, our results indicate that endogenous attention benefits performance by modulating the contribution of high-frequency information in order to flexibly adjust spatial resolution according to task demands. PMID:28118103

Trends in spatio-temporal dynamics of visceral leishmaniasis cases in a highly-endemic focus of Bihar, India: an investigation based on GIS tools.

PubMed

Mandal, Rakesh; Kesari, Shreekant; Kumar, Vijay; Das, Pradeep

2018-04-02

Visceral leishmaniasis (VL) in Bihar State (India) continues to be endemic, despite the existence of effective treatment and a vector control program to control disease morbidity. A clear understanding of spatio-temporal distribution of VL may improve surveillance and control implementation. This study explored the trends in spatio-temporal dynamics of VL endemicity at a meso-scale level in Vaishali District, based on geographical information systems (GIS) tools and spatial statistical analysis. A GIS database was used to integrate the VL case data from the study area between 2009 and 2014. All cases were spatially linked at a meso-scale level. Geospatial techniques, such as GIS-layer overlaying and mapping, were employed to visualize and detect the spatio-temporal patterns of a VL endemic outbreak across the district. The spatial statistic Moran's I Index (Moran's I) was used to simultaneously evaluate spatial-correlation between endemic villages and the spatial distribution patterns based on both the village location and the case incidence rate (CIR). Descriptive statistics such as mean, standard error, confidence intervals and percentages were used to summarize the VL case data. There were 624 endemic villages with 2719 (average 906 cases/year) VL cases during 2012-2014. The Moran's I revealed a cluster pattern (P < 0.05) of CIR distribution at the meso-scale level. On average, 68 villages were newly-endemic each year. Of which 93.1% of villages' endemicity were found to have occurred on the peripheries of the previous year endemic villages. The mean CIR of the endemic villages that were peripheral to the following year newly-endemic villages, compared to all endemic villages of the same year, was higher (P < 0.05). The results show that the VL endemicity of new villages tends to occur on the periphery of villages endemic in the previous year. High-CIR plays a major role in the spatial dispersion of the VL cases between non-endemic and endemic villages. This information can help achieve VL elimination throughout the Indian subcontinent by improving vector control design and implementation in highly-endemic district.

The symphony of the damned: racial discourse, complex political emergencies and humanitarian aid.

PubMed

Duffield, M

1996-09-01

This paper concerns the manner in which the West is responding to protracted political crises beyond its borders. It examines the conceptual world-view that aid agencies bring to complex emergencies and which shapes action. The paper provides an analysis of developmentalism. That is, the currently dominant idea of development which is an adapted form of multiculturalism. It is based on the empowerment of cultural differences and the relativisation of progress. As a variant of multiculturalism, developmentalism is part of Western racial discourse. In terms of understanding conflict, it establishes a mirror-image relationship with new rascist ideas premised on cultural pluralism inevitably leading to social breakdown, violence and anarchy. To the contrary, with its functional view of social harmony, libertine developmentalism claims that even unresolved political crisis constitutes a development opportunity. Developmentalism, like culturalism generally, is incapable of analysing power. It therefore cannot understand the effects and significance of its own organisational forms. Moreover, since the absence of power translates into operational neutrality in a war zone, it is also unable to analyse the nature of new political formations emerging in the global periphery. That is, the so-called weak or failed states, warlords and so on. This functional ignorance has allowed a widespread incorporation of humanitarian aid into the fabric of political violence. Developmentalism is an essential underpinning for the growing organisational accommodation to ongoing conflict and eroding standards of justice and accountability.

Structure of the spatial periphery of the {sup 11}Li and {sup 11}Be isobars

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

Galanina, L. I., E-mail: galan-lidiya@mail.ru; Zelenskaya, N. S.

2016-07-15

On the basis of the shell model with an extended basis, the structure of {sup 9}Li-{sup 9}Be to {sup 11}Li-{sup 11}Be nuclei is examined with allowance for the competition of {sup jj} coupling and Majorana exchange forces via considering the sequential addition of neutrons, and the respective wave functions are determined. A formalism for calculating the spectroscopic factor for a dineutron and for individual neutrons in nuclei whose wave functions incorporate the mixing of shell configurations is developed. The reactions {sup 9}Li(t, p){sup 11}Li and {sup 9}Be(t, p){sup 11}Be treated with allowance for the mechanisms of dineutron stripping and amore » sequential transfer of two neutrons are considered as an indicator of the proposed structure of lithium and berylliumisotopes. The parameters of the optical potentials, the wave functions for the bound states of transferred particles, and the interaction potentials corresponding to them are determined from a comparison of the theoretical angular distribution of protons from the reaction {sup 9}Be(t, p){sup 11}Be with its experimental counterpart. It is shown that a dineutron periphery of size about 6.4 fm is present in the {sup 11}Li nucleus and that a single-neutron periphery of size about 8 fm is present in the {sup 11}Be nucleus.« less

Transitions between Central and Peripheral Vision Create Spatial/Temporal Distortions: A Hypothesis Concerning the Perceived Break of the Curveball

PubMed Central

Shapiro, Arthur; Lu, Zhong-Lin; Huang, Chang-Bing; Knight, Emily; Ennis, Robert

2010-01-01

Background The human visual system does not treat all parts of an image equally: the central segments of an image, which fall on the fovea, are processed with a higher resolution than the segments that fall in the visual periphery. Even though the differences between foveal and peripheral resolution are large, these differences do not usually disrupt our perception of seamless visual space. Here we examine a motion stimulus in which the shift from foveal to peripheral viewing creates a dramatic spatial/temporal discontinuity. Methodology/Principal Findings The stimulus consists of a descending disk (global motion) with an internal moving grating (local motion). When observers view the disk centrally, they perceive both global and local motion (i.e., observers see the disk's vertical descent and the internal spinning). When observers view the disk peripherally, the internal portion appears stationary, and the disk appears to descend at an angle. The angle of perceived descent increases as the observer views the stimulus from further in the periphery. We examine the first- and second-order information content in the display with the use of a three-dimensional Fourier analysis and show how our results can be used to describe perceived spatial/temporal discontinuities in real-world situations. Conclusions/Significance The perceived shift of the disk's direction in the periphery is consistent with a model in which foveal processing separates first- and second-order motion information while peripheral processing integrates first- and second-order motion information. We argue that the perceived distortion may influence real-world visual observations. To this end, we present a hypothesis and analysis of the perception of the curveball and rising fastball in the sport of baseball. The curveball is a physically measurable phenomenon: the imbalance of forces created by the ball's spin causes the ball to deviate from a straight line and to follow a smooth parabolic path. However, the curveball is also a perceptual puzzle because batters often report that the flight of the ball undergoes a dramatic and nearly discontinuous shift in position as the ball nears home plate. We suggest that the perception of a discontinuous shift in position results from differences between foveal and peripheral processing. PMID:20967247

Method and Apparatus of Implementing a Magnetic Shield Flux Sweeper

NASA Technical Reports Server (NTRS)

Sadleir, John E. (Inventor)

2018-01-01

The present invention relates to a method and apparatus of protecting magnetically sensitive devices with a shield, including: a non-superconducting metal or lower transition temperature (T.sub.c) material compared to a higher transition temperature material, disposed in a magnetic field; means for creating a spatially varying order parameter's |.PSI.(r,T)|.sup.2 in a non-superconducting metal or a lower transition temperature material; wherein a spatially varying order parameter is created by a proximity effect, such that the non-superconducting metal or the lower transition temperature material becomes superconductive as a temperature is lowered, creating a flux-free Meissner state at a center thereof, in order to sweep magnetic flux lines to the periphery.

Uniform spatial distribution of collagen fibril radii within tendon implies local activation of pC-collagen at individual fibrils

NASA Astrophysics Data System (ADS)

Rutenberg, Andrew D.; Brown, Aidan I.; Kreplak, Laurent

2016-08-01

Collagen fibril cross-sectional radii show no systematic variation between the interior and the periphery of fibril bundles, indicating an effectively constant rate of collagen incorporation into fibrils throughout the bundle. Such spatially homogeneous incorporation constrains the extracellular diffusion of collagen precursors from sources at the bundle boundary to sinks at the growing fibrils. With a coarse-grained diffusion equation we determine stringent bounds, using parameters extracted from published experimental measurements of tendon development. From the lack of new fibril formation after birth, we further require that the concentration of diffusing precursors stays below the critical concentration for fibril nucleation. We find that the combination of the diffusive bound, which requires larger concentrations to ensure homogeneous fibril radii, and lack of nucleation, which requires lower concentrations, is only marginally consistent with fully processed collagen using conservative bounds. More realistic bounds may leave no consistent concentrations. Therefore, we propose that unprocessed pC-collagen diffuses from the bundle periphery followed by local C-proteinase activity and subsequent collagen incorporation at each fibril. We suggest that C-proteinase is localized within bundles, at fibril surfaces, during radial fibrillar growth. The much greater critical concentration of pC-collagen, as compared to fully processed collagen, then provides broad consistency between homogeneous fibril radii and the lack of fibril nucleation during fibril growth.

Cerebral TOF Angiography at 7T: Impact of B1+ Shimming with a 16-Channel Transceiver Array

PubMed Central

Schmitter, Sebastian; Wu, Xiaoping; Adriany, Gregor; Auerbach, Edward J.; Uğurbil, Kâmil; Van de Moortele, Pierre-François

2014-01-01

Purpose Time-of-flight (TOF) MR imaging is clinically among the most common cerebral non-contrast enhanced MR angiography techniques allowing for high spatial resolution. As shown by several groups TOF contrast significantly improves at ultra-high field (UHF) of B0=7T, however, spatially varying transmit B1 (B1+) fields at 7T reduce TOF contrast uniformity, typically resulting in sub-optimal contrast and reduced vessel conspicuity in the brain periphery. Methods Using a 16-channel B1+ shimming system we compare different dynamically applied B1+ phase shimming approaches on the RF excitation to improve contrast homogeneity for a (0.5 mm)3 resolution multi-slab TOF acquisition. In addition, B1+ shimming applied on the venous saturation pulse was investigated to improve venous suppression, subcutaneous fat signal reduction and enhanced background suppression originating from MT effect. Results B1+ excitation homogeneity was improved by a factor 2.2 to 2.6 on average depending on the shimming approach, compared to a standard CP-like phase setting, leading to improved vessel conspicuity particularly in the periphery. Stronger saturation, higher fat suppression and improved background suppression were observed when dynamically applying B1+ shimming on the venous saturation pulse. Conclusion B1+ shimming can significantly improve high resolution TOF vascular investigations at UHF, holding strong promise for non contrast-enhanced clinical applications. PMID:23640915

Ki-67 acts as a biological surfactant to disperse mitotic chromosomes

PubMed Central

Cuylen, Sara; Blaukopf, Claudia; Politi, Antonio Z.; Müller-Reichert, Thomas; Neumann, Beate; Poser, Ina; Ellenberg, Jan; Hyman, Anthony A.; Gerlich, Daniel W.

2016-01-01

Summary Eukaryotic genomes are partitioned into chromosomes, which during mitosis form compact and spatially well-separated mechanical bodies1–3.This enables chromosomes to move independently of each other for segregation of precisely one copy of the genome to each of the nascent daughter cells. Despite insights into the spatial organization of mitotic chromosomes4 and the discovery of proteins at the chromosome surface3,5,6, the molecular and biophysical basis of mitotic chromosome individuality have remained unclear. We report that Ki-67, a component of the mitotic chromosome periphery, prevents chromosomes from collapsing into a single chromatin mass after nuclear envelope disassembly, thus enabling independent chromosome motility and efficient interactions with the mitotic spindle. The chromosome separation function of Ki-67 is not confined within a specific protein domain but correlates with size and net charge of truncation mutants that apparently lack secondary structure. This suggests that Ki-67 forms a steric and electrical barrier, similar to surface-active agents (surfactants) that disperse particles or phase-separated liquid droplets in solvents. Fluorescence correlation spectroscopy showed a high surface density of Ki-67 and dual-color labeling of both protein termini revealed an extended molecular conformation, indicating brush-like arrangements that are characteristic for polymeric surfactants. Our study thus elucidates a biomechanical role of the mitotic chromosome periphery and suggests that natural proteins can function as surfactants in intracellular compartmentalization. PMID:27362226

Multiwavelength studies of H II region NGC 2467

NASA Astrophysics Data System (ADS)

Yadav, Ram Kesh; Pandey, A. K.; Sharma, Saurabh; Eswaraiah, C.

2013-06-01

We present the multiwavelength studies of the H II region Sh2-311 to explore the effects of massive stars on low-mass star formation. In this study we have used optical (UBVI) data from ESO 2.2m Wide Field Imager (WFI), Near-Infrared (NIR) (JHKs) data from CTIO 4m Blanco Telescope and archival Spitzer 8μm data. Based on stellar density contours and dust distribution we have divided the complex into three regions i.e., Haffner 19 (H19), Haffner 18 (H18) and NGC 2467. Using the UBVI data we have estimated the basic parameters of these regions. We have constructed the (J - H)/(H - Ks) color-color diagram and a J/(J - H) color-magnitude diagram to identify young stellar objects (YSOs) and to estimate their masses. Spatial distribution of the YSOs indicates that most of them are distributed at the periphery of the H II region and ionizing star may be responsible for the triggering of star formation at the periphery of the H II region.

Sustainability and Displacement: Assessing the Spatial Pattern of Residential Moves Near Rail Transit

DOT National Transportation Integrated Search

2017-11-01

Rail transits association with gentrification has been a presence in the public discourse for some time and Los Angeles is no different. There is a prevailing public perception that Los Angeles' recent boom in rail transit development causes an in...

Excess folate during adolescence suppresses thyroid function with permanent deficits in motivation and spatial memory

PubMed Central

Sittig, L. J.; Herzing, L. B. K.; Xie, H.; Batra, K. K.; Shukla, P. K.; Redei, E. E.

2012-01-01

Cognitive and memory deficits can be caused or exacerbated by dietary folate deficiency, which has been combatted by the addition of folate to grains and dietary supplements. The recommended dose of the B9 vitamin folate is 400 μg/day for adolescents and non-pregnant adults, and consumption above the recommended daily allowance is not considered to be detrimental. However, the effects of excess folate have not been tested in adolescence when neuro and endocrine development suggest possible vulnerability to long-term cognitive effects. We administered folate-supplemented (8.0 mg folic acid/kg diet) or control lab chow (2.7 mg folic acid/kg diet) to rats ad libitum from 30 to 60 days of age, and subsequently tested their motivation and learning and memory in the Morris water maze. We found that folate-supplemented animals had deficits in motivation and spatial memory, but they showed no changes of the learning- and memory-related molecules growth-associated protein-43 or Gs-α subunit protein in the hippocampus. They had decreased levels of thyroxine (T4) and triiodothyronine (T3) in the periphery and decreased protein levels of thyroid receptor-α1 and -α2 (TRα1 and TRα2) in the hippocampus. The latter may have been due to an observed increase of cytosine–phosphate–guanosine island methylation within the putative thyroid hormone receptor-α promoter, which we have mapped for the first time in the rat. Overall, folate supplementation in adolescence led to motivational and spatial memory deficits that may have been mediated by suppressed thyroid hormone function in the periphery and hippocampus. PMID:22050771

Excess folate during adolescence suppresses thyroid function with permanent deficits in motivation and spatial memory.

PubMed

Sittig, L J; Herzing, L B K; Xie, H; Batra, K K; Shukla, P K; Redei, E E

2012-03-01

Cognitive and memory deficits can be caused or exacerbated by dietary folate deficiency, which has been combatted by the addition of folate to grains and dietary supplements. The recommended dose of the B9 vitamin folate is 400 µg/day for adolescents and non-pregnant adults, and consumption above the recommended daily allowance is not considered to be detrimental. However, the effects of excess folate have not been tested in adolescence when neuro and endocrine development suggest possible vulnerability to long-term cognitive effects. We administered folate-supplemented (8.0 mg folic acid/kg diet) or control lab chow (2.7 mg folic acid/kg diet) to rats ad libitum from 30 to 60 days of age, and subsequently tested their motivation and learning and memory in the Morris water maze. We found that folate-supplemented animals had deficits in motivation and spatial memory, but they showed no changes of the learning- and memory-related molecules growth-associated protein-43 or Gs-α subunit protein in the hippocampus. They had decreased levels of thyroxine (T4) and triiodothyronine (T3) in the periphery and decreased protein levels of thyroid receptor-α1 and -α2 (TRα1 and TRα2) in the hippocampus. The latter may have been due to an observed increase of cytosine-phosphate-guanosine island methylation within the putative thyroid hormone receptor-α promoter, which we have mapped for the first time in the rat. Overall, folate supplementation in adolescence led to motivational and spatial memory deficits that may have been mediated by suppressed thyroid hormone function in the periphery and hippocampus. © 2011 The Authors. Genes, Brain and Behavior © 2011 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Tracking calcification in tissue-engineered bone using synchrotron micro-FTIR and SEM.

PubMed

Deegan, Anthony J; Cinque, Gianfelice; Wehbe, Katia; Konduru, Sandeep; Yang, Ying

2015-02-01

One novel tissue engineering approach to mimic in vivo bone formation is the use of aggregate or micromass cultures. Various qualitative and quantitative techniques, such as histochemical staining, protein assay kits and RT-PCR, have been used previously on cellular aggregate studies to investigate how these intricate arrangements lead to mature bone tissue. However, these techniques struggle to reveal spatial and temporal distribution of proliferation and mineralization simultaneously. Synchrotron-based Fourier transform infrared microspectroscopy (micro-FTIR) offers a unique insight at the molecular scale by coupling high IR sensitivity to organic matter with the high spatial resolution allowed by diffraction limited SR microbeam. This study is set to investigate the effects of culture duration and aggregate size on the dynamics and spatial distribution of calcification in engineered bone aggregates by a combination of micro-FTIR and scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX). A murine bone cell line has been used, and small/large bone aggregates have been induced using different chemically treated culture substrates. Our findings suggest that bone cell aggregate culturing can greatly increase levels of mineralization over short culture periods. The size of the aggregates influences mineralisation rates with larger aggregates mineralizing at a faster rate than their smaller counterparts. The micro-FTIR mapping has demonstrated that mineralization in the larger aggregates initiated from the periphery and spread to the centre, whilst the smaller aggregates have more minerals in the centre at the early stage and deposited more in the periphery after further culturing, implying that aggregate size influences calcification distribution and development over time. SEM/EDX data correlates well with the micro-FTIR results for the total mineral content. Thus, synchrotron-based micro-FTIR can accurately track mineralization process/mechanism in the engineered bone.

Predicting Ki67% expression from DCE-MR images of breast tumors using textural kinetic features in tumor habitats

NASA Astrophysics Data System (ADS)

Chaudhury, Baishali; Zhou, Mu; Farhidzadeh, Hamidreza; Goldgof, Dmitry B.; Hall, Lawrence O.; Gatenby, Robert A.; Gillies, Robert J.; Weinfurtner, Robert J.; Drukteinis, Jennifer S.

2016-03-01

The use of Ki67% expression, a cell proliferation marker, as a predictive and prognostic factor has been widely studied in the literature. Yet its usefulness is limited due to inconsistent cut off scores for Ki67% expression, subjective differences in its assessment in various studies, and spatial variation in expression, which makes it difficult to reproduce as a reliable independent prognostic factor. Previous studies have shown that there are significant spatial variations in Ki67% expression, which may limit its clinical prognostic utility after core biopsy. These variations are most evident when examining the periphery of the tumor vs. the core. To date, prediction of Ki67% expression from quantitative image analysis of DCE-MRI is very limited. This work presents a novel computer aided diagnosis framework to use textural kinetics to (i) predict the ratio of periphery Ki67% expression to core Ki67% expression, and (ii) predict Ki67% expression from individual tumor habitats. The pilot cohort consists of T1 weighted fat saturated DCE-MR images from 17 patients. Support vector regression with a radial basis function was used for predicting the Ki67% expression and ratios. The initial results show that texture features from individual tumor habitats are more predictive of the Ki67% expression ratio and spatial Ki67% expression than features from the whole tumor. The Ki67% expression ratio could be predicted with a root mean square error (RMSE) of 1.67%. Quantitative image analysis of DCE-MRI using textural kinetic habitats, has the potential to be used as a non-invasive method for predicting Ki67 percentage and ratio, thus more accurately reporting high KI-67 expression for patient prognosis.

Chromosome territories reposition during DNA damage-repair response

PubMed Central

2013-01-01

Background Local higher-order chromatin structure, dynamics and composition of the DNA are known to determine double-strand break frequencies and the efficiency of repair. However, how DNA damage response affects the spatial organization of chromosome territories is still unexplored. Results Our report investigates the effect of DNA damage on the spatial organization of chromosome territories within interphase nuclei of human cells. We show that DNA damage induces a large-scale spatial repositioning of chromosome territories that are relatively gene dense. This response is dose dependent, and involves territories moving from the nuclear interior to the periphery and vice versa. Furthermore, we have found that chromosome territory repositioning is contingent upon double-strand break recognition and damage sensing. Importantly, our results suggest that this is a reversible process where, following repair, chromosome territories re-occupy positions similar to those in undamaged control cells. Conclusions Thus, our report for the first time highlights DNA damage-dependent spatial reorganization of whole chromosomes, which might be an integral aspect of cellular damage response. PMID:24330859

Interorganellar Regulation of Lysosome Positioning by the Golgi Apparatus through Rab34 Interaction with Rab-interacting Lysosomal Protein

PubMed Central

Wang, Tuanlao; Hong, Wanjin

2002-01-01

We present evidence to suggest the existence of a regulatory pathway for the Golgi apparatus to modulate the spatial positioning of otherwise distantly located lysosomes. Rab34, a new member of the Rab GTPase family, is associated primarily with the Golgi apparatus. Expression of wild-type or GTP-restricted but not GDP-restricted versions of Rab34 causes spatial redistribution of lysosomes from the periphery to the peri-Golgi region. The regulation of lysosomal positioning by Rab34 depends on its association with the membrane mediated by prenylation and its direct interaction with Rab-interacting lysosomal protein (RILP). This biological activity, mediated by Rab34-RILP interaction, is dependent on Lys82 in the switch I region. Our results have uncovered a novel mechanism for the Golgi apparatus to regulate the spatial distribution of another organelle. PMID:12475955

Entorhinal cortex receptive fields are modulated by spatial attention, even without movement

PubMed Central

König, Peter; König, Seth; Buffalo, Elizabeth A

2018-01-01

Grid cells in the entorhinal cortex allow for the precise decoding of position in space. Along with potentially playing an important role in navigation, grid cells have recently been hypothesized to make a general contribution to mental operations. A prerequisite for this hypothesis is that grid cell activity does not critically depend on physical movement. Here, we show that movement of covert attention, without any physical movement, also elicits spatial receptive fields with a triangular tiling of space. In monkeys trained to maintain central fixation while covertly attending to a stimulus moving in the periphery we identified a significant population (20/141, 14% neurons at a FDR <5%) of entorhinal cells with spatially structured receptive fields. This contrasts with recordings obtained in the hippocampus, where grid-like representations were not observed. Our results provide evidence that neurons in macaque entorhinal cortex do not rely on physical movement. PMID:29537964

Spatially Distinct Neutrophil Responses within the Inflammatory Lesions of Pneumonic Plague

PubMed Central

Stasulli, Nikolas M.; Eichelberger, Kara R.; Price, Paul A.; Pechous, Roger D.; Montgomery, Stephanie A.; Parker, Joel S.

2015-01-01

ABSTRACT During pneumonic plague, the bacterium Yersinia pestis elicits the development of inflammatory lung lesions that continue to expand throughout infection. This lesion development and persistence are poorly understood. Here, we examine spatially distinct regions of lung lesions using laser capture microdissection and transcriptome sequencing (RNA-seq) analysis to identify transcriptional differences between lesion microenvironments. We show that cellular pathways involved in leukocyte migration and apoptosis are downregulated in the center of lung lesions compared to the periphery. Probing for the bacterial factor(s) important for the alteration in neutrophil survival, we show both in vitro and in vivo that Y. pestis increases neutrophil survival in a manner that is dependent on the type III secretion system effector YopM. This research explores the complexity of spatially distinct host-microbe interactions and emphasizes the importance of cell relevance in assays in order to fully understand Y. pestis virulence. PMID:26463167

On the identification of normal modes of oscillation from observations of the solar periphery

NASA Technical Reports Server (NTRS)

Gough, D. D.; Latour, J.

1984-01-01

The decomposition of solar oscillations into their constituent normal modes requires a knowledge of both the spatial and temporal variation of the perturbation to the Sun's surface. The task is especially difficult when only limited spatial information is available. Observations of the limb darkening function, for example, are probably sensitive to too large a number of modes to permit most of the modes to be identified in a power spectrum of measurements at only a few points on the limb, unless the results are combined with other data. A procedure was considered by which the contributions from quite small groups of modes to spatially well resolved data obtained at any instant can be extracted from the remaining modes. Combining these results with frequency information then permits the modes to be identified, at least if their frequencies are low enough to ensure that modes of high degree do not contribute substantially to the signal.

The Distribution of Attention Across a Talker's Face

ERIC Educational Resources Information Center

Thompson, Laura A.; Malmberg, Jeanne; Goodell, Neil K.; Boring, Ronald L.

2004-01-01

In 2 experiments, a novel experimental paradigm investigated how spatial attention is distributed across a talker's face during auditory-visual speech discourse processing. Dots were superimposed onto several talkers' faces for 17-msec durations on the talker's left side, mouth, right side, and eyebrow area. Participants reported the locations of…

Mobilities of Youth: Social and Spatial Trajectories in a Segregated Sweden

ERIC Educational Resources Information Center

Lindgren, Joakim; Lundahl, Lisbeth

2010-01-01

This article explores youth mobilities in three geographic and socio-economically diverse Swedish contexts. The concept of mobility has become an important feature of individualistic discourses of responsibility relating to inclusion, lifelong learning and self-regulating entrepreneurial behaviour. This article draws attention to the fact that…

Single or Multiple? Looking at Location in Movement Notation

ERIC Educational Resources Information Center

Munjee, Tara

2015-01-01

Contemporary discourse embraces notions of human movement in space as occurring in both set, singular locations and also through many locations and ever-changing fields. Mobile conceptions of location and spatiality particularly relate to patterns of everyday contemporary life and are embraced in some artistic and performance practices. Graphic…

Spatial Strategies in the Description of Complex Configurations

ERIC Educational Resources Information Center

Tenbrink, Thora; Coventry, Kenny R.; Andonova, Elena

2011-01-01

How people describe complex arrangements of objects in a small-scale setting has not been sufficiently investigated to predict when discourse strategies shift versus remain stable. In a study involving 100 native German participants, we investigated speakers' choices of perspective, as well as location and orientation information, when describing…

The influence of disturbed habitat on the spatial ecology of Argentine black and white tegu (Tupinambis merianae), a recent invader in the Everglades ecosystem (Florida, USA)

USGS Publications Warehouse

Klug, Page E.; Reed, Robert N.; Mazzotti, Frank J.; McEachern, Michelle A.; Vinci, Joy J.; Craven, Katelin K.; Yackel Adams, Amy A.

2015-01-01

The threat of invasive species is often intensified in disturbed habitat. To optimize control programs, it is necessary to understand how degraded habitat influences the behavior of invasive species. We conducted a radio telemetry study to characterize movement and habitat use of introduced male Argentine black and white tegus (Tupinambis merianae) in the Everglades of southern Florida from May to August 2012 at the core and periphery of the introduced range. Tegus at the periphery moved farther per day (mean 131.7 ± 11.6 m, n = 6) compared to tegus at the core (mean 50.3 ± 12.4 m, n = 6). However, activity ranges were not significantly smaller in the core (mean 19.4 ± 8.4 ha, n = 6) compared to periphery (mean 29.1 ± 5.2 ha, n = 6). Peripheral activity ranges were more linear due to activity being largely restricted to levee habitat surrounded by open water or marsh. Tegus were located in shrub or tree habitat (mean 96%) more often than expected based on random locations (mean 58%), and the percent cover of trees and shrubs was higher in activity ranges (mean 61%) than the general study area (17%). Our study highlighted the ability of tegus to spread across the Florida landscape, especially in linear disturbed habitats where increased movement occurred and in areas of altered hydrology where movement is not restricted by water.

Substructures and Tidal Distortions in the Magellanic Stellar Periphery

NASA Astrophysics Data System (ADS)

Mackey, Dougal; Koposov, Sergey; Da Costa, Gary; Belokurov, Vasily; Erkal, Denis; Kuzma, Pete

2018-05-01

We use a new panoramic imaging survey conducted with the Dark Energy Camera to map the stellar fringes of the Large and Small Magellanic Clouds (LMC/SMC) to extremely low surface brightness V ≈ 32 mag arcsec‑2. Our results starkly illustrate the closely interacting nature of the LMC–SMC pair. We show that the outer LMC disk is strongly distorted, exhibiting an irregular shape, evidence for warping, and significant truncation on the side facing the SMC. Large diffuse stellar substructures are present both to the north and south of the LMC, and in the inter-Cloud region. At least one of these features appears as co-spatial with the bridge of RR Lyrae stars that connects the Clouds. The SMC is highly disturbed; we confirm the presence of tidal tails, as well as a large line-of-sight depth on the side closest to the LMC. Young, intermediate-age, and ancient stellar populations in the SMC exhibit strikingly different spatial distributions. In particular, those with ages ∼1.5–4 Gyr exhibit a spheroidal distribution with a centroid offset from that of the oldest stars by several degrees toward the LMC. We speculate that the gravitational influence of the LMC may already have been perturbing the gaseous component of the SMC several Gyr ago. With careful modeling, the variety of substructures and tidal distortions evident in the Magellanic periphery should tightly constrain the interaction history of the Clouds.

The role of density-dependent and -independent processes in spawning habitat selection by salmon in an Arctic riverscape.

PubMed

Huntsman, Brock M; Falke, Jeffrey A; Savereide, James W; Bennett, Katrina E

2017-01-01

Density-dependent (DD) and density-independent (DI) habitat selection is strongly linked to a species' evolutionary history. Determining the relative importance of each is necessary because declining populations are not always the result of altered DI mechanisms but can often be the result of DD via a reduced carrying capacity. We developed spatially and temporally explicit models throughout the Chena River, Alaska to predict important DI mechanisms that influence Chinook salmon spawning success. We used resource-selection functions to predict suitable spawning habitat based on geomorphic characteristics, a semi-distributed water-and-energy balance hydrologic model to generate stream flow metrics, and modeled stream temperature as a function of climatic variables. Spawner counts were predicted throughout the core and periphery spawning sections of the Chena River from escapement estimates (DD) and DI variables. Additionally, we used isodar analysis to identify whether spawners actively defend spawning habitat or follow an ideal free distribution along the riverscape. Aerial counts were best explained by escapement and reference to the core or periphery, while no models with DI variables were supported in the candidate set. Furthermore, isodar plots indicated habitat selection was best explained by ideal free distributions, although there was strong evidence for active defense of core spawning habitat. Our results are surprising, given salmon commonly defend spawning resources, and are likely due to competition occurring at finer spatial scales than addressed in this study.

The role of density-dependent and –independent processes in spawning habitat selection by salmon in an Arctic riverscape

DOE PAGES

Huntsman, Brock M.; Falke, Jeffrey A.; Savereide, James W.; ...

2017-05-22

Density-dependent (DD) and density-independent (DI) habitat selection is strongly linked to a species’ evolutionary history. Determining the relative importance of each is necessary because declining populations are not always the result of altered DI mechanisms but can often be the result of DD via a reduced carrying capacity. Here, we developed spatially and temporally explicit models throughout the Chena River, Alaska to predict important DI mechanisms that influence Chinook salmon spawning success. We used resource-selection functions to predict suitable spawning habitat based on geomorphic characteristics, a semi-distributed water-and-energy balance hydrologic model to generate stream flow metrics, and modeled stream temperaturemore » as a function of climatic variables. Spawner counts were predicted throughout the core and periphery spawning sections of the Chena River from escapement estimates (DD) and DI variables. In addition, we used isodar analysis to identify whether spawners actively defend spawning habitat or follow an ideal free distribution along the riverscape. Aerial counts were best explained by escapement and reference to the core or periphery, while no models with DI variables were supported in the candidate set. Moreover, isodar plots indicated habitat selection was best explained by ideal free distributions, although there was strong evidence for active defense of core spawning habitat. These results are surprising, given salmon commonly defend spawning resources, and are likely due to competition occurring at finer spatial scales than addressed in this study.« less

The role of density-dependent and –independent processes in spawning habitat selection by salmon in an Arctic riverscape

USGS Publications Warehouse

Huntsman, Brock M.; Falke, Jeffrey A.; Savereide, James W.; Bennett, Katrina E.

2017-01-01

Density-dependent (DD) and density-independent (DI) habitat selection is strongly linked to a species’ evolutionary history. Determining the relative importance of each is necessary because declining populations are not always the result of altered DI mechanisms but can often be the result of DD via a reduced carrying capacity. We developed spatially and temporally explicit models throughout the Chena River, Alaska to predict important DI mechanisms that influence Chinook salmon spawning success. We used resource-selection functions to predict suitable spawning habitat based on geomorphic characteristics, a semi-distributed water-and-energy balance hydrologic model to generate stream flow metrics, and modeled stream temperature as a function of climatic variables. Spawner counts were predicted throughout the core and periphery spawning sections of the Chena River from escapement estimates (DD) and DI variables. Additionally, we used isodar analysis to identify whether spawners actively defend spawning habitat or follow an ideal free distribution along the riverscape. Aerial counts were best explained by escapement and reference to the core or periphery, while no models with DI variables were supported in the candidate set. Furthermore, isodar plots indicated habitat selection was best explained by ideal free distributions, although there was strong evidence for active defense of core spawning habitat. Our results are surprising, given salmon commonly defend spawning resources, and are likely due to competition occurring at finer spatial scales than addressed in this study.

Mapping Everyday: Gender, Blackness, and Discourse in Urban Contexts

ERIC Educational Resources Information Center

Taylor, L. Hill, Jr.; Helfenbein, Robert J.

2009-01-01

This article argues that by using theories of the spatial to understand how situated materiality (i.e., place) and contestations of identity matter when conceiving global and curricular space, educators may interrupt and rearticulate practices and systems of oppression. By focusing on globalization writ large, there is danger of leaving important…

How to Chat in English and Chinese: Emerging Digital Language Conventions

ERIC Educational Resources Information Center

Lotherington, Heather; Xu, Yejun

2004-01-01

Rapid changes in language form and function occurring in digital environments present teachers and students of second languages alike with conundrums as to language and discourse standards. Factors affecting the changes that are emerging in digital English include the spatial and temporal possibilities and constraints of the medium, digital…

Drawing the Line between Constituent Structure and Coherence Relations in Visual Narratives

ERIC Educational Resources Information Center

Cohn, Neil; Bender, Patrick

2017-01-01

Theories of visual narrative understanding have often focused on the changes in meaning across a sequence, like shifts in characters, spatial location, and causation, as cues for breaks in the structure of a discourse. In contrast, the theory of visual narrative grammar posits that hierarchic "grammatical" structures operate at the…

Endothelial permeability is controlled by spatially defined cytoskeletal mechanics: atomic force microscopy force mapping of pulmonary endothelial monolayer.

PubMed

Birukova, Anna A; Arce, Fernando T; Moldobaeva, Nurgul; Dudek, Steven M; Garcia, Joe G N; Lal, Ratnesh; Birukov, Konstantin G

2009-03-01

Actomyosin contraction directly regulates endothelial cell (EC) permeability, but intracellular redistribution of cytoskeletal tension associated with EC permeability is poorly understood. We used atomic force microscopy (AFM), EC permeability assays, and fluorescence microscopy to link barrier regulation, cell remodeling, and cytoskeletal mechanical properties in EC treated with barrier-protective as well as barrier-disruptive agonists. Thrombin, vascular endothelial growth factor, and hydrogen peroxide increased EC permeability, disrupted cell junctions, and induced stress fiber formation. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine, hepatocyte growth factor, and iloprost tightened EC barriers, enhanced peripheral actin cytoskeleton and adherens junctions, and abolished thrombin-induced permeability and EC remodeling. AFM force mapping and imaging showed differential distribution of cell stiffness: barrier-disruptive agonists increased stiffness in the central region, and barrier-protective agents decreased stiffness in the center and increased it at the periphery. Attenuation of thrombin-induced permeability correlates well with stiffness changes from the cell center to periphery. These results directly link for the first time the patterns of cell stiffness with specific EC permeability responses.

Visible contrast energy metrics for detection and discrimination

NASA Astrophysics Data System (ADS)

Ahumada, Albert J.; Watson, Andrew B.

2013-03-01

Contrast energy was proposed by Watson, Barlow, and Robson (Science, 1983) as a useful metric for representing luminance contrast target stimuli because it represents the detectability of the stimulus in photon noise for an ideal observer. We propose here the use of visible contrast energy metrics for detection and discrimination among static luminance patterns. The visibility is approximated with spatial frequency sensitivity weighting and eccentricity sensitivity weighting. The suggested weighting functions revise the Standard Spatial Observer (Watson and Ahumada, J. Vision, 2005) for luminance contrast detection , extend it into the near periphery, and provide compensation for duration. Under the assumption that the detection is limited only by internal noise, both detection and discrimination performance can be predicted by metrics based on the visible energy of the difference images.

Turbulence intensity and spatial integral scale during compression and expansion strokes in a four-cycle reciprocating engine

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

Ikegami, M.; Shioji, M.; Nishimoto, K.

1987-01-01

A laser homodyne technique is applied to measure turbulence intensities and spatial scales during compression and expansion strokes in a non-fired engine. By using this technique, relative fluid motion in a turbulent flow is detected directly without cyclic variation biases caused by fluctuation in the main flow. Experiments are performed at different engine speeds, compression ratios, and induction swirl ratios. In no-swirl cases the turbulence field near the compression end is almost uniform, whereas in swirled cases both the turbulence intensity and the scale near the cylinder axis are higher than those in the periphery. In addition, based on themore » measured results, the k-epsilon two-equation turbulence model under the influence of compression is discussed.« less

Dendrimers and methods of preparing same through proportionate branching

DOEpatents

Yu, Yihua; Yue, Xuyi

2015-09-15

The present invention provides for monodispersed dendrimers having a core, branches and periphery ends, wherein the number of branches increases exponentially from the core to the periphery end and the length of the branches increases exponentially from the periphery end to the core, thereby providing for attachment of chemical species at the periphery ends without exhibiting steric hindrance.

Core-periphery structure requires something else in the network

NASA Astrophysics Data System (ADS)

Kojaku, Sadamori; Masuda, Naoki

2018-04-01

A network with core-periphery structure consists of core nodes that are densely interconnected. In contrast to a community structure, which is a different meso-scale structure of networks, core nodes can be connected to peripheral nodes and peripheral nodes are not densely interconnected. Although core-periphery structure sounds reasonable, we argue that it is merely accounted for by heterogeneous degree distributions, if one partitions a network into a single core block and a single periphery block, which the famous Borgatti–Everett algorithm and many succeeding algorithms assume. In other words, there is a strong tendency that high-degree and low-degree nodes are judged to be core and peripheral nodes, respectively. To discuss core-periphery structure beyond the expectation of the node’s degree (as described by the configuration model), we propose that one needs to assume at least one block of nodes apart from the focal core-periphery structure, such as a different core-periphery pair, community or nodes not belonging to any meso-scale structure. We propose a scalable algorithm to detect pairs of core and periphery in networks, controlling for the effect of the node’s degree. We illustrate our algorithm using various empirical networks.

Magnifying Democracy and Sovereignty In Indonesian Maritime Governance Through Open Marine Spatial Data Practice

NASA Astrophysics Data System (ADS)

Yudono, Adipandang

2018-05-01

This research has attempted to discover a new approach in magnifying democracy and sovereignty in the Indonesian maritime governance through open marine spatial data practices between governments and citizens. The research has been done in order to fill in the gap of bridging marine spatial data or information at all government levels and between citizen and government. The research predominantly used qualitative methods with specifically approach was discourse analysis using legal document analysis and in-depth interview to elites, and local digital mapping communities. The coherence and synergy of maritime development can be achieved through dialogue between the elites and the public. A solution to bridge political communication between the elite and the public is sharing or open marine spatial data and information.

Space, Time, History: The Reassertion of Space in Social Theory

ERIC Educational Resources Information Center

Peters, Michael A.; Kessl, Fabian

2009-01-01

The reassertion of space is discussed as an analytical awareness of the past obsession with temporal logics. Theorists now understand that social sciences discourses were shaped by a preoccupation with the temporal scales and logics of development considered as natural processes. The spatial turn in social theory is often seen to be a process of…

Mapping Civic Engagement: A Case Study of Service-Learning in Appalachia

ERIC Educational Resources Information Center

Mann, Jessica; Casebeer, Daniel

2016-01-01

This study uses social cartography to map student perceptions of a co-curricular service-learning project in an impoverished rural community. As a complement to narrative discourse, mapping provides an opportunity to visualize not only the spatial nature of the educational experience but also, in this case, the benefits of civic engagement. The…

Author as Dialogic Site: A Spatial Metaphor for Authoritative Voice.

ERIC Educational Resources Information Center

Haas, Mark

In a recent debate on authority in the discourse of English Studies scholarship, writers seem to line up on two sides: the "friends of the familiar essay," and those who advocate "the article." The essay/article debate seems to be part of the conflict opened by the Renaissance over writing, selfhood, power, and knowledge. What…

Ethnic Tourism and the Big Song: Public Pedagogies and the Ambiguity of Environmental Discourse in Southwest China

ERIC Educational Resources Information Center

Wu, Jinting

2017-01-01

The article examines two forms of public pedagogies in a rural region of Southwest China-tourism and ethnic songs-to illustrate their contested roles in transforming local relations with natural and built environment. While tourism development daily alters the village landscape by spatial intervention, demolition, and construction, the…

[Spatial analysis of mortality from cardiovascular diseases in Madrid City, Spain].

PubMed

Gómez-Barroso, Diana; Prieto-Flores, María-Eugenia; Mellado San Gabino, Ana; Moreno Jiménez, Antonio

2015-01-01

Cardiovascular disease is the leading cause of death worldwide, but its spatial distribution is not homogeneous. The objective of this study is to analyze the spatial pattern of mortality from these diseases for men and women, in the populated urban area (AUP) of the municipality of Madrid, and to identify spatial aggregations. An ecological study was carried out by census tract, for men and women in 2010. Standardized Mortality Ratio (SMR), Relative Risk Smoothing (RRS) and Posterior Probability (PP) were calculated to consider the spatial pattern of the disease. To identify spatial clusters the Moran index (Moran I) and the Local Index of Spatial Autocorrelation (LISA) were used. The results were mapped. SMR higher than 1.1 was observed mainly in central areas among men and in peripheral areas among women. The PP that RRS was higher than 1 surpassed 0.8 in the center and in the periphery, in both men and women. Moran's I was 0.04 for men and 0.03 for women (p <0.05 in both cases). Sex differences were observed in the spatial distribution of mortality cases. RME RRS and PP maps showed a heterogeneous pattern in men, whereas in women a clearer pattern was detected, with a relatively higher risk in peripheral areas of the AUP. The LISA method showed similar patterns to those previously observed.

Drawing the line between constituent structure and coherence relations in visual narratives

PubMed Central

Cohn, Neil; Bender, Patrick

2016-01-01

Theories of visual narrative understanding have often focused on the changes in meaning across a sequence, like shifts in characters, spatial location, and causation, as cues for breaks in the structure of a discourse. In contrast, the theory of Visual Narrative Grammar posits that hierarchic “grammatical” structures operate at the discourse level using categorical roles for images, which may or may not co-occur with shifts in coherence. We therefore examined the relationship between narrative structure and coherence shifts in the segmentation of visual narrative sequences using a “segmentation task” where participants drew lines between images in order to divide them into sub-episodes. We used regressions to analyze the influence of the expected constituent structure boundary, narrative categories, and semantic coherence relationships on the segmentation of visual narrative sequences. Narrative categories were a stronger predictor of segmentation than linear coherence relationships between panels, though both influenced participants’ divisions. Altogether, these results support the theory that meaningful sequential images use a narrative grammar that extends above and beyond linear semantic shifts between discourse units. PMID:27709982

Drawing the line between constituent structure and coherence relations in visual narratives.

PubMed

Cohn, Neil; Bender, Patrick

2017-02-01

Theories of visual narrative understanding have often focused on the changes in meaning across a sequence, like shifts in characters, spatial location, and causation, as cues for breaks in the structure of a discourse. In contrast, the theory of visual narrative grammar posits that hierarchic "grammatical" structures operate at the discourse level using categorical roles for images, which may or may not co-occur with shifts in coherence. We therefore examined the relationship between narrative structure and coherence shifts in the segmentation of visual narrative sequences using a "segmentation task" where participants drew lines between images in order to divide them into subepisodes. We used regressions to analyze the influence of the expected constituent structure boundary, narrative categories, and semantic coherence relationships on the segmentation of visual narrative sequences. Narrative categories were a stronger predictor of segmentation than linear coherence relationships between panels, though both influenced participants' divisions. Altogether, these results support the theory that meaningful sequential images use a narrative grammar that extends above and beyond linear semantic shifts between discourse units. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Link between orientation and retinotopic maps in primary visual cortex

PubMed Central

Paik, Se-Bum; Ringach, Dario L.

2012-01-01

Maps representing the preference of neurons for the location and orientation of a stimulus on the visual field are a hallmark of primary visual cortex. It is not yet known how these maps develop and what function they play in visual processing. One hypothesis postulates that orientation maps are initially seeded by the spatial interference of ON- and OFF-center retinal receptive field mosaics. Here we show that such a mechanism predicts a link between the layout of orientation preferences around singularities of different signs and the cardinal axes of the retinotopic map. Moreover, we confirm the predicted relationship holds in tree shrew primary visual cortex. These findings provide additional support for the notion that spatially structured input from the retina may provide a blueprint for the early development of cortical maps and receptive fields. More broadly, it raises the possibility that spatially structured input from the periphery may shape the organization of primary sensory cortex of other modalities as well. PMID:22509015

Forecasting the impact of transport improvements on commuting and residential choice

NASA Astrophysics Data System (ADS)

Elhorst, J. Paul; Oosterhaven, Jan

2006-03-01

This paper develops a probabilistic, competing-destinations, assignment model that predicts changes in the spatial pattern of the working population as a result of transport improvements. The choice of residence is explained by a new non-parametric model, which represents an alternative to the popular multinominal logit model. Travel times between zones are approximated by a normal distribution function with different mean and variance for each pair of zones, whereas previous models only use average travel times. The model’s forecast error of the spatial distribution of the Dutch working population is 7% when tested on 1998 base-year data. To incorporate endogenous changes in its causal variables, an almost ideal demand system is estimated to explain the choice of transport mode, and a new economic geography inter-industry model (RAEM) is estimated to explain the spatial distribution of employment. In the application, the model is used to forecast the impact of six mutually exclusive Dutch core-periphery railway proposals in the projection year 2020.

On the identification of normal modes of oscillation from observations of the solar periphery

NASA Technical Reports Server (NTRS)

Gough, D. O.; Latour, J.

1984-01-01

The decomposition of solar oscillations into their constituent normal modes requires a knowledge of both the spatial and temporal variation of the perturbation to the sun's surface. The task can be especially difficult when only limited spatial information is available. Observations of the limb-darkening function, for example, are probably sensitive to too large a number of modes to permit most of the modes to be identified in a power spectrum of measurements at only a few points on the limb, unless the results are combined with other data. In this paper a procedure is considered by which the contributions from quite small groups of modes to spatially well resolved data obtained at any instant can be extracted from the remaining modes. Combining these results with frequency information then permits the modes to be identified, at least if their frequencies are low enough to ensure that modes of high degree do not contribute substantially to the signal.

Physics Teaching in the Search for Its Self: From Physics as a Discipline to Physics as a Discipline-Culture

NASA Astrophysics Data System (ADS)

Tseitlin, Michael; Galili, Igal

The crisis in physics education necessitates searching for new relevant meanings of physics knowledge. This paper advocates regarding physics as the dialogue among discipline-cultures, rather than as a cluster of disciplines to be an appropriate subject of science education. In a discipline-culture one can distinguish elements of knowledge as belonging to either (1) central principles and paradigms - nucleus, (2) normal disciplinary area - body of knowledge or (3) rival knowledge of the subject - periphery. It appears that Physics cannot be represented as a simple dynamic wholeness, that is, cannot be arranged in a single tripartite (triadic) structure (this result presents a deconstruction), but incorporates several discipline-cultures. Bound together by family similarity, they maintain a conceptual discourse. Teaching physics as a culture is performed in polyphonic space of different worldviews; in other words, it is performed in a Kontrapunkt. Implications of the tripartite code are suggested with regard to representation of scientific revolutions, individual conceptual change, physics curricula and the typology of students learning science.

Analysis of the contaminants released from municipal solid waste landfill site: A case study.

PubMed

Samadder, S R; Prabhakar, R; Khan, D; Kishan, D; Chauhan, M S

2017-02-15

Release and transport of leachate from municipal solid waste landfills pose a potential hazard to both surrounding ecosystems and human populations. In the present study, soil, groundwater, and surface water samples were collected from the periphery of a municipal solid waste landfill (located at Ranital of Jabalpur, Madhya Pradesh, India) for laboratory analysis to understand the release of contaminants. The landfill does not receive any solid wastes for dumping now as the same is under a landfill closure plan. Groundwater and soil samples were collected from the bore holes of 15m deep drilled along the periphery of the landfill and the surface water samples were collected from the existing surface water courses near the landfill. The landfill had neither any bottom liner nor any leachate collection and treatment system. Thus the leachate generated from the landfills finds paths into the groundwater and surrounding surface water courses. Concentrations of various physico-chemical parameters including some toxic metals (in collected groundwater, soil, and surface water samples) and microbiological parameters (in surface water samples) were determined. The analyzed data were integrated into ArcGIS environment and the spatial distribution of the metals and other physic- chemical parameter across the landfill was extrapolated to observe the distribution. The statistical analysis and spatial variations indicated the leaching of metals from the landfill to the groundwater aquifer system. The study will help the readers and the municipal engineers to understand the release of contaminants from landfills for better management of municipal solid wastes. Copyright © 2016 Elsevier B.V. All rights reserved.

Spatial and Temporal Patterns of Biocide Action against Staphylococcus epidermidis Biofilms▿ ‡

PubMed Central

Davison, William M.; Pitts, Betsey; Stewart, Philip S.

2010-01-01

The dynamic antimicrobial action of chlorine, a quaternary ammonium compound, glutaraldehyde, and nisin within biofilm cell clusters of Staphylococcus epidermidis was investigated using time-lapse confocal scanning laser microscopy. The technique allowed for the simultaneous imaging of changes in biofilm structure and disruption of cellular membrane integrity through the loss of an unbound fluorophore loaded into bacterial cells prior to antimicrobial challenge. Each of the four antimicrobial agents produced distinct spatial and temporal patterns of fluorescence loss. The antimicrobial action of chlorine was localized around the periphery of biofilm cell clusters. Chlorine was the only antimicrobial agent that caused any biofilm removal. Treatment with the quaternary ammonium compound caused membrane permeabilization that started at the periphery of cell clusters, then migrated steadily inward. A secondary pattern superimposed on the penetration dynamic suggested a subpopulation of less-susceptible cells. These bacteria lost fluorescence much more slowly than the majority of the population. Nisin caused a rapid and uniform loss of green fluorescence from all parts of the biofilm without any removal of biofilm. Glutaraldehyde caused no biofilm removal and also no loss of membrane integrity. Measurements of biocide penetration and action time at the center of cell clusters yielded 46 min for 10 mg liter−1 chlorine, 21 min for 50 mg liter−1 chlorine, 25 min for the quaternary ammonium compound, and 4 min for nisin. These results underscore the distinction between biofilm removal and killing and reinforce the critical role of biocide reactivity in determining the rate of biofilm penetration. PMID:20457816

[Spatial arrangement of macro-, midi- and microchromosomes in transcriptionally active nuclei of growing oocytes in birds of the order galliformes].

PubMed

Maslova, A V; Krasikova, A V

2011-01-01

Three-dimensional genome organization in the cell nucleus reflects its functional state and is one of the regulatory levels of gene expression. Thus, a detailed exploration of the interrelations between the genome spatial organization and functioning is essential. In this work, three-dimensional genome organization in growing oocytes of Galliform birds, with giant transcriptionally active nucleus characterized by nearly absolute lack of structural constraints on chromosome decondensation, is analyzed in detail. Radial distribution of three groups of chromosomes with different size and gene density in the nuclei of chicken and Japanese quail oocytes was analyzed using confocal laser scanning microscopy followed by the 3D-reconstruction. The chromosome position relative to the nuclear center was estimated by analyzing its localization in the certain radial zones of the nucleus and direct distance measurements from the centre of the nucleus to the terminal regions and the center of gravity of the chromosome. It has been shown that, in the transcriptionally active nuclei of avian oocytes, chromosomes are located at a significant distance from the nuclear envelope and the gene-rich microchromosomes have no preferential location close to the center of the nucleus and are localized mainly at the periphery of the region occupied by the whole chromosome set. Therefore the radial distribution of lampbrush chromosomes in the oocyte nucleus does not obey the regularity of the spatial arrangement of chromosomes in the interphase nucleus according to which the gene-rich chromosome territories are located at the nuclear center and the gene-poor ones are at the nuclear periphery. With the help of visualization of 3D-preserved lampbrush chromosomes in the intact nucleus, we have confirmed the presence of the repulsion forces between the lateral loops of lampbrush half-bivalents and the lack of interactions between the heterochromatic segments of different bivalents at the lampbrush stage of oogenesis.

PinX1 is recruited to the mitotic chromosome periphery by Nucleolin and facilitates chromosome congression.

PubMed

Li, Na; Yuan, Kai; Yan, Feng; Huo, Yuda; Zhu, Tongge; Liu, Xing; Guo, Zhen; Yao, Xuebiao

2009-06-19

Mitotic chromosome movements are orchestrated by interactions between spindle microtubules and chromosomes. It is well known that kinetochore is the major site where microtubule-chromosome attachment occurs. However, the functions of other domains of chromosome such as chromosome periphery have remained elusive. Our previous studies show that PinX1 distributes to chromosome periphery and kinetochore during mitosis, and harbors the microtubule binding activity. Here we report that PinX1 interacts with Nucleolin, a chromosome periphery protein, through its C-termini. Deconvolution microscopic analyses show PinX1 mainly co-localizes with Nucleolin at chromosome periphery in prometaphase. Moreover, depletion of Nucleolin abolishes chromosome periphery localizations of PinX1, suggesting a functional interrelationship between PinX1 and Nucleolin. Importantly, repression of PinX1 and Nucleolin abrogates chromosome segregation in real-time mitosis, validating the functional importance of PinX1-Nucleolin interaction. We propose PinX1 is recruited to chromosome periphery by Nucleolin and a complex of PinX1 and Nucleolin is essential for faithful chromosome congression.

Centripetal myosin redistribution in thrombin-stimulated platelets. Relationship to platelet Factor 4 secretion.

PubMed

Painter, R G; Ginsberg, M H

1984-11-01

We have examined the F-actin and myosin distribution in resting and thrombin-activated platelets by double label immunofluorescence microscopy. In resting, discoid platelets, F-actin and myosin staining was distributed in a diffuse pattern throughout the interior of the cell with slight accentuation at the cell periphery. In contrast, platelet factor 4 antigen (PF4) was more centrally localized in a fine punctate distribution which is consistent with its localization in alpha-granules. Within 5 sec after thrombin stimulation both F-actin and myosin staining were increased at the periphery of the now spherical platelets. Subsequently, a myosin-containing spherical structure decreased in diameter closely surrounding a phase-dense central zone. In contrast, F-actin staining continued to be accentuated at the cell periphery and was prominent in filopodia and blebs. As previously shown, PF4 staining was localized after 30 sec within large intracellular masses that corresponded to closed vacuolar structures at the ultrastructural level. Morphometric analysis of electron micrographs showed that formation of these vacuolar structures kinetically paralleled alpha-granule disappearance and preceded PF4 release. These PF4-containing structures translocated to the cell periphery after 1-3 min, where they appeared to fuse with the plasma membrane. Ultrastructural analysis of thin sections showed that the myosin-rich spherical structure spatially and temporally correlated with a band of microfilaments that closely surrounded the organelle-rich central zone of the cell. Morphometric analysis of these micrographs showed that the absolute volume of this central zone decreased with time after thrombin addition, showing a significant change after 15 sec and reaching a maximum value after 3-5 min. Changes in the volume of this compartment kinetically preceded PF4 release. On the basis of these data, we propose that an actomyosin contractile force is generated which centripetally redistributes the myosinrich structure and organelle zone. Conceivably this inward force may not only accelerate granule-granule fusion to form intracellular secretory vacuoles, but may also provide aid in their extrusion toward the platelet plasma membrane.

Enhancement of breast periphery region in digital mammography

NASA Astrophysics Data System (ADS)

Menegatti Pavan, Ana Luiza; Vacavant, Antoine; Petean Trindade, Andre; Quini, Caio Cesar; Rodrigues de Pina, Diana

2018-03-01

Volumetric breast density has been shown to be one of the strongest risk factor for breast cancer diagnosis. This metric can be estimated using digital mammograms. During mammography acquisition, breast is compressed and part of it loses contact with the paddle, resulting in an uncompressed region in periphery with thickness variation. Therefore, reliable density estimation in the breast periphery region is a problem, which affects the accuracy of volumetric breast density measurement. The aim of this study was to enhance breast periphery to solve the problem of thickness variation. Herein, we present an automatic algorithm to correct breast periphery thickness without changing pixel value from internal breast region. The correction pixel values from periphery was based on mean values over iso-distance lines from the breast skin-line using only adipose tissue information. The algorithm detects automatically the periphery region where thickness should be corrected. A correction factor was applied in breast periphery image to enhance the region. We also compare our contribution with two other algorithms from state-of-the-art, and we show its accuracy by means of different quality measures. Experienced radiologists subjectively evaluated resulting images from the tree methods in relation to original mammogram. The mean pixel value, skewness and kurtosis from histogram of the three methods were used as comparison metric. As a result, the methodology presented herein showed to be a good approach to be performed before calculating volumetric breast density.

IS THERE CONVERGENCE ACROSS COUNTRIES? A SPATIAL APPROACH

PubMed Central

Berry, Heather; Guillen, Mauro F.; Hendi, Arun S.

2014-01-01

We analyze convergence across countries over the last half century as a result of globalizing forces. Drawing on theories of modernization, dependency, the world-system, political trade blocs, and the world-society, we consider economic, demographic, knowledge, financial, and political dimensions of convergence. Using a new methodology, we calculate the minimum volume ellipsoid encompassing different groupings of countries, finding that during the 1960–2009 period, countries have not evolved significantly closer or similar to one another, although groups of countries based on their core-periphery status or membership in trade blocs exhibit increasing internal convergence and divergence between one another. PMID:25580035

Why do shape aftereffects increase with eccentricity?

PubMed

Gheorghiu, Elena; Kingdom, Frederick A A; Bell, Jason; Gurnsey, Rick

2011-12-20

Studies have shown that spatial aftereffects increase with eccentricity. Here, we demonstrate that the shape-frequency and shape-amplitude aftereffects, which describe the perceived shifts in the shape of a sinusoidal-shaped contour following adaptation to a slightly different sinusoidal-shaped contour, also increase with eccentricity. Why does this happen? We first demonstrate that the perceptual shift increases with eccentricity for stimuli of fixed sizes. These shifts are not attenuated by variations in stimulus size; in fact, at each eccentricity the degree of perceptual shift is scale-independent. This scale independence is specific to the aftereffect because basic discrimination thresholds (in the absence of adaptation) decrease as size increases. Structural aspects of the displays were found to have a modest effect on the degree of perceptual shift; the degree of adaptation depends modestly on distance between stimuli during adaptation and post-adaptation testing. There were similar temporal rates of decline of adaptation across the visual field and higher post-adaptation discrimination thresholds in the periphery than in the center. The observed results are consistent with greater sensitivity reduction in adapted mechanisms following adaptation in the periphery or an eccentricity-dependent increase in the bandwidth of the shape-frequency- and shape-amplitude-selective mechanisms.

Microtubule release from the centrosome in migrating cells

PubMed Central

Abal, Miguel; Piel, Matthieu; Bouckson-Castaing, Veronique; Mogensen, Mette; Sibarita, Jean-Baptiste; Bornens, Michel

2002-01-01

In migrating cells, force production relies essentially on a polarized actomyosin system, whereas the spatial regulation of actomyosin contraction and substrate contact turnover involves a complex cooperation between the microtubule (MT) and the actin filament networks (Goode, B.L., D.G. Drubin, and G. Barnes. 2000. Curr. Opin. Cell Biol., 12:63–71). Targeting and capture of MT plus ends at the cell periphery has been described, but whether or not the minus ends of these MTs are anchored at the centrosome is not known. Here, we show that release of short MTs from the centrosome is frequent in migrating cells and that their transport toward the cell periphery is blocked when dynein activity is impaired. We further show that MT release, but not MT nucleation or polymerization dynamics, is abolished by overexpression of the centrosomal MT-anchoring protein ninein. In addition, a dramatic inhibition of cell migration was observed; but, contrary to cells treated by drugs inhibiting MT dynamics, polarized membrane ruffling activity was not affected in ninein overexpressing cells. We thus propose that the balance between MT minus-end capture and release from the centrosome is critical for efficient cell migration. PMID:12473683

Effects of residential relocation on household and commuting expenditures in Shanghai, China.

PubMed

Day, Jennifer; Cervero, Robert

2010-01-01

Over the past three decades, China's cities have undergone massive spatial restructuring in the wake of market reforms and economic growth. One consequence has been a rapid migration of urban residents to the periphery. Some movers have been forced out either by rising urban rents or government reclamation of their residences. Others have relocated willingly to modernized housing or for other lifestyle reasons. This article examines the effects of relocation to the urban edge on household well-being. It explores the factors underlying changes in housing and transportation costs as households move to the periphery. The research also examines whether those who moved involuntarily are affected differently from those who moved by choice. Results show that, relative to those who moved by choice, involuntary movers are disproportionately and adversely affected in terms of job accessibility, commute time, housing consumption and disposable income. The findings also show that, compared with higher-income households, lower-income groups are disproportionately affected in relation to housing costs, accessibility losses, disposable income and household worker composition. These results indicate that relocation compensation for involuntarily relocated households should be expanded to include more than just housing value: it should encompass urban location changes, household needs and relocation costs.

The prognostic significance of lymphatics in colorectal liver metastases.

PubMed

Muralidharan, Vijayaragavan; Nguyen, Linh; Banting, Jonathan; Christophi, Christopher

2014-01-01

Background. Colorectal Cancer (CRC) is the most common form of cancer diagnosed in Australia across both genders. Approximately, 40%-60% of patients with CRC develop metastasis, the liver being the most common site. Almost 70% of CRC mortality can be attributed to the development of liver metastasis. This study examines the pattern and density of lymphatics in colorectal liver metastases (CLM) as predictors of survival following hepatic resection for CLM. Methods. Patient tissue samples were obtained from the Victorian Cancer Biobank. Immunohistochemistry was used to examine the spatial differences in blood and lymphatic vessel densities between different regions within the tumor (CLM) and surrounding host tissue. Lymphatic vessel density (LVD) was assessed as a potential prognostic marker. Results. Patients with low lymphatic vessel density in the tumor centre, tumor periphery, and adjacent normal liver demonstrated a significant disease-free survival advantage compared to patients with high lymphatic vessel density (P = 0.01, P > 0.01, and P = 0.05, resp.). Lymphatic vessel density in the tumor centre and periphery and adjacent normal liver was an accurate predictive marker of disease-free survival (P = 0.05). Conclusion. Lymphatic vessel density in CLM appears to be an accurate predictor of recurrence and disease-free survival.

STAR CLUSTER POPULATIONS IN THE OUTER DISKS OF NEARBY GALAXIES

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

Herbert-Fort, Stephane; Zaritsky, Dennis; Moustakas, John

We present a Large Binocular Telescope imaging study that characterizes the star cluster component of nearby galaxy outer disks (beyond the optical radius R{sub 25}). Expanding on the pilot project of Herbert-Fort et al., we present deep ({approx}27.5 mag V-band point-source limiting magnitude) U- and V-band imaging of six galaxies: IC 4182, NGC 3351, NGC 4736, NGC 4826, NGC 5474, and NGC 6503. We find that the outer disk of each galaxy is populated with marginally resolved star clusters with masses {approx}10{sup 3} M{sub Sun} and ages up to {approx}1 Gyr (masses and ages are limited by the depth ofmore » our imaging and uncertainties are large given how photometry can be strongly affected by the presence or absence of a few stars in such low-mass systems), and that they are typically found out to at least 2 R{sub 25} but sometimes as far as 3-4 R{sub 25}-even beyond the apparent H I disk. The mean rate of cluster formation for 1 R{sub 25} {<=} R {<=} 1.5 R{sub 25} is at least one every {approx}2.5 Myr and the clusters are spatially correlated with the H I, most strongly with higher density gas near the periphery of the optical disk and with lower density neutral gas at the H I disk periphery. We hypothesize that the clusters near the edge of the optical disk are formed in the extension of spiral structure from the inner disk and are a fairly consistent phenomenon and that the clusters formed at the periphery of the H I disk are the result of accretion episodes.« less

Lack of oblique astigmatism in the chicken eye.

PubMed

Maier, Felix M; Howland, Howard C; Ohlendorf, Arne; Wahl, Siegfried; Schaeffel, Frank

2015-04-01

Primate eyes display considerable oblique off-axis astigmatism which could provide information on the sign of defocus that is needed for emmetropization. The pattern of peripheral astigmatism is not known in the chicken eye, a common model of myopia. Peripheral astigmatism was mapped out over the horizontal visual field in three chickens, 43 days old, and in three near emmetropic human subjects, average age 34.7years, using infrared photoretinoscopy. There were no differences in astigmatism between humans and chickens in the central visual field (chicks -0.35D, humans -0.65D, n.s.) but large differences in the periphery (i.e. astigmatism at 40° in the temporal visual field: humans -4.21D, chicks -0.63D, p<0.001, unpaired t-test). The lack of peripheral astigmatism in chicks was not due to differences in corneal shape. Perhaps related to their superior peripheral optics, we found that chickens had excellent visual performance also in the far periphery. Using an automated optokinetic nystagmus paradigm, no difference was observed in spatial visual performance with vision restricted to either the central 67° of the visual field or to the periphery beyond 67°. Accommodation was elicited by stimuli presented far out in the visual field. Transscleral images of single infrared LEDs showed no sign of peripheral astigmatism. The chick may be the first terrestrial vertebrate described to lack oblique astigmatism. Since corneal shape cannot account for the difference in astigmatism in humans and chicks, it must trace back to the design of the crystalline lens. The lack of peripheral astigmatism in chicks also excludes a role in emmetropization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Geostatistics as a tool to study mite dispersion in physic nut plantations.

PubMed

Rosado, J F; Picanço, M C; Sarmento, R A; Pereira, R M; Pedro-Neto, M; Galdino, T V S; de Sousa Saraiva, A; Erasmo, E A L

2015-08-01

Spatial distribution studies in pest management identify the locations where pest attacks on crops are most severe, enabling us to understand and predict the movement of such pests. Studies on the spatial distribution of two mite species, however, are rather scarce. The mites Polyphagotarsonemus latus and Tetranychus bastosi are the major pests affecting physic nut plantations (Jatropha curcas). Therefore, the objective of this study was to measure the spatial distributions of P. latus and T. bastosi in the physic nut plantations. Mite densities were monitored over 2 years in two different plantations. Sample locations were georeferenced. The experimental data were analyzed using geostatistical analyses. The total mite density was found to be higher when only one species was present (T. bastosi). When both the mite species were found in the same plantation, their peak densities occurred at different times. These mites, however, exhibited uniform spatial distribution when found at extreme densities (low or high). However, the mites showed an aggregated distribution in intermediate densities. Mite spatial distribution models were isotropic. Mite colonization commenced at the periphery of the areas under study, whereas the high-density patches extended until they reached 30 m in diameter. This has not been reported for J. curcas plants before.

Slit/Robo Signaling Mediates Spatial Positioning of Spiral Ganglion Neurons during Development of Cochlear Innervation

PubMed Central

Wang, Sheng-zhi; Ibrahim, Leena A.; Kim, Young J.; Gibson, Daniel A.; Leung, Haiwen C.; Yuan, Wei; Zhang, Ke K.; Tao, Huizhong W.

2013-01-01

During the development of periphery auditory circuits, spiral ganglion neurons (SGNs) extend their neurites to innervate cochlear hair cells (HCs) with their soma aggregated into a cluster spatially segregated from the cochlear sensory epithelium. The molecular mechanisms underlying this spatial patterning remain unclear. In this study, in situ hybridization in the mouse cochlea suggests that Slit2 and its receptor, Robo1/2, exhibit apparently complementary expression patterns in the spiral ganglion and its nearby region, the spiral limbus. In Slit2 and Robo1/2 mutants, the spatial restriction of SGNs was disrupted. Mispositioned SGNs were found to scatter in the space between the cochlear epithelium and the main body of spiral ganglion, and the neurites of mispositioned SGNs were misrouted and failed to innervate HCs. Furthermore, in Robo1/2 mutants, SGNs were displaced toward the cochlear epithelium as an entirety. Examination of different embryonic stages in the mutants revealed that the mispositioning of SGNs was due to a progressive displacement to ectopic locations after their initial normal settlement at an earlier stage. Our results suggest that Slit/Robo signaling imposes a restriction force on SGNs to ensure their precise positioning for correct SGN-HC innervations. PMID:23884932

Progressive Presentations of Place-Based Identities in Meg Rosoff's "How I Live Now"

ERIC Educational Resources Information Center

Lockney, Karen

2013-01-01

This article provides a close reading of Meg Rosoff's award-winning novel "How I Live Now". It argues that an understanding of the text can be extended through an application of ideas found in contemporary spatial discourse concerning place. Reading the novel within this context allows a discussion of ways in which it draws on…

Mapping organelle motion reveals a vesicular conveyor belt spatially replenishing secretory vesicles in stimulated chromaffin cells.

PubMed

Maucort, Guillaume; Kasula, Ravikiran; Papadopulos, Andreas; Nieminen, Timo A; Rubinsztein-Dunlop, Halina; Meunier, Frederic A

2014-01-01

How neurosecretory cells spatially adjust their secretory vesicle pools to replenish those that have fused and released their hormonal content is currently unknown. Here we designed a novel set of image analyses to map the probability of tracked organelles undergoing a specific type of movement (free, caged or directed). We then applied our analysis to time-lapse z-stack confocal imaging of secretory vesicles from bovine Chromaffin cells to map the global changes in vesicle motion and directionality occurring upon secretagogue stimulation. We report a defined region abutting the cortical actin network that actively transports secretory vesicles and is dissipated by actin and microtubule depolymerizing drugs. The directionality of this "conveyor belt" towards the cell surface is activated by stimulation. Actin and microtubule networks therefore cooperatively probe the microenvironment to transport secretory vesicles to the periphery, providing a mechanism whereby cells globally adjust their vesicle pools in response to secretagogue stimulation.

Expanding signaling-molecule wavefront model of cell polarization in the Drosophila wing primordium.

PubMed

Wortman, Juliana C; Nahmad, Marcos; Zhang, Peng Cheng; Lander, Arthur D; Yu, Clare C

2017-07-01

In developing tissues, cell polarization and proliferation are regulated by morphogens and signaling pathways. Cells throughout the Drosophila wing primordium typically show subcellular localization of the unconventional myosin Dachs on the distal side of cells (nearest the center of the disc). Dachs localization depends on the spatial distribution of bonds between the protocadherins Fat (Ft) and Dachsous (Ds), which form heterodimers between adjacent cells; and the Golgi kinase Four-jointed (Fj), which affects the binding affinities of Ft and Ds. The Fj concentration forms a linear gradient while the Ds concentration is roughly uniform throughout most of the wing pouch with a steep transition region that propagates from the center to the edge of the pouch during the third larval instar. Although the Fj gradient is an important cue for polarization, it is unclear how the polarization is affected by cell division and the expanding Ds transition region, both of which can alter the distribution of Ft-Ds heterodimers around the cell periphery. We have developed a computational model to address these questions. In our model, the binding affinity of Ft and Ds depends on phosphorylation by Fj. We assume that the asymmetry of the Ft-Ds bond distribution around the cell periphery defines the polarization, with greater asymmetry promoting cell proliferation. Our model predicts that this asymmetry is greatest in the radially-expanding transition region that leaves polarized cells in its wake. These cells naturally retain their bond distribution asymmetry after division by rapidly replenishing Ft-Ds bonds at new cell-cell interfaces. Thus we predict that the distal localization of Dachs in cells throughout the pouch requires the movement of the Ds transition region and the simple presence, rather than any specific spatial pattern, of Fj.

Diet-induced obesity attenuates endotoxin-induced cognitive deficits.

PubMed

Setti, Sharay E; Littlefield, Alyssa M; Johnson, Samantha W; Kohman, Rachel A

2015-03-15

Activation of the immune system can impair cognitive function, particularly on hippocampus dependent tasks. Several factors such as normal aging and prenatal experiences can modify the severity of these cognitive deficits. One additional factor that may modulate the behavioral response to immune activation is obesity. Prior work has shown that obesity alters the activity of the immune system. Whether diet-induced obesity (DIO) influences the cognitive deficits associated with inflammation is currently unknown. The present study explored whether DIO alters the behavioral response to the bacterial endotoxin, lipopolysaccharide (LPS). Female C57BL/6J mice were fed a high-fat (60% fat) or control diet (10% fat) for a total of five months. After consuming their respective diets for four months, mice received an LPS or saline injection and were assessed for alterations in spatial learning. One month later, mice received a second injection of LPS or saline and tissue samples were collected to assess the inflammatory response within the periphery and central nervous system. Results showed that LPS administration impaired spatial learning in the control diet mice, but had no effect in DIO mice. This lack of a cognitive deficit in the DIO female mice is likely due to a blunted inflammatory response within the brain. While cytokine production within the periphery (i.e., plasma, adipose, and spleen) was similar between the DIO and control mice, the DIO mice failed to show an increase in IL-6 and CD74 in the brain following LPS administration. Collectively, these data indicate that DIO can reduce aspects of the neuroinflammatory response as well as blunt the behavioral reaction to an immune challenge. Copyright © 2014 Elsevier Inc. All rights reserved.

Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

NASA Astrophysics Data System (ADS)

Jiao, L. M.; Tang, X.; Liu, X. P.

2017-09-01

Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

Humanoid monocular stereo measuring system with two degrees of freedom using bionic optical imaging system

NASA Astrophysics Data System (ADS)

Du, Jia-Wei; Wang, Xuan-Yin; Zhu, Shi-Qiang

2017-10-01

Based on the process by which the spatial depth clue is obtained by a single eye, a monocular stereo vision to measure the depth information of spatial objects was proposed in this paper and a humanoid monocular stereo measuring system with two degrees of freedom was demonstrated. The proposed system can effectively obtain the three-dimensional (3-D) structure of spatial objects of different distances without changing the position of the system and has the advantages of being exquisite, smart, and flexible. The bionic optical imaging system we proposed in a previous paper, named ZJU SY-I, was employed and its vision characteristic was just like the resolution decay of the eye's vision from center to periphery. We simplified the eye's rotation in the eye socket and the coordinated rotation of other organs of the body into two rotations in the orthogonal direction and employed a rotating platform with two rotation degrees of freedom to drive ZJU SY-I. The structure of the proposed system was described in detail. The depth of a single feature point on the spatial object was deduced, as well as its spatial coordination. With the focal length adjustment of ZJU SY-I and the rotation control of the rotation platform, the spatial coordinates of all feature points on the spatial object could be obtained and then the 3-D structure of the spatial object could be reconstructed. The 3-D structure measurement experiments of two spatial objects with different distances and sizes were conducted. Some main factors affecting the measurement accuracy of the proposed system were analyzed and discussed.

Learning English in the Periphery: A View from Myanmar (Burma)

ERIC Educational Resources Information Center

Tin, Tan Bee

2014-01-01

Although researchers have called for the investigation of local vernacular learning and teaching practices in various ELT (English language teaching) contexts, studies conducted in the Periphery are fewer in number. This study attempts to understand English learning experiences of a group of students from the Periphery, who were studying English…

Feeling form: the neural basis of haptic shape perception.

PubMed

Yau, Jeffrey M; Kim, Sung Soo; Thakur, Pramodsingh H; Bensmaia, Sliman J

2016-02-01

The tactile perception of the shape of objects critically guides our ability to interact with them. In this review, we describe how shape information is processed as it ascends the somatosensory neuraxis of primates. At the somatosensory periphery, spatial form is represented in the spatial patterns of activation evoked across populations of mechanoreceptive afferents. In the cerebral cortex, neurons respond selectively to particular spatial features, like orientation and curvature. While feature selectivity of neurons in the earlier processing stages can be understood in terms of linear receptive field models, higher order somatosensory neurons exhibit nonlinear response properties that result in tuning for more complex geometrical features. In fact, tactile shape processing bears remarkable analogies to its visual counterpart and the two may rely on shared neural circuitry. Furthermore, one of the unique aspects of primate somatosensation is that it contains a deformable sensory sheet. Because the relative positions of cutaneous mechanoreceptors depend on the conformation of the hand, the haptic perception of three-dimensional objects requires the integration of cutaneous and proprioceptive signals, an integration that is observed throughout somatosensory cortex. Copyright © 2016 the American Physiological Society.

Object detection in natural scenes: Independent effects of spatial and category-based attention.

PubMed

Stein, Timo; Peelen, Marius V

2017-04-01

Humans are remarkably efficient in detecting highly familiar object categories in natural scenes, with evidence suggesting that such object detection can be performed in the (near) absence of attention. Here we systematically explored the influences of both spatial attention and category-based attention on the accuracy of object detection in natural scenes. Manipulating both types of attention additionally allowed for addressing how these factors interact: whether the requirement for spatial attention depends on the extent to which observers are prepared to detect a specific object category-that is, on category-based attention. The results showed that the detection of targets from one category (animals or vehicles) was better than the detection of targets from two categories (animals and vehicles), demonstrating the beneficial effect of category-based attention. This effect did not depend on the semantic congruency of the target object and the background scene, indicating that observers attended to visual features diagnostic of the foreground target objects from the cued category. Importantly, in three experiments the detection of objects in scenes presented in the periphery was significantly impaired when observers simultaneously performed an attentionally demanding task at fixation, showing that spatial attention affects natural scene perception. In all experiments, the effects of category-based attention and spatial attention on object detection performance were additive rather than interactive. Finally, neither spatial nor category-based attention influenced metacognitive ability for object detection performance. These findings demonstrate that efficient object detection in natural scenes is independently facilitated by spatial and category-based attention.

The psychophysical periphery effect crosses the vertical meridian.

PubMed

Kuyk, T; Niculescu, D

2001-01-01

This study measured the periphery effect and compared its magnitude when the peripheral stimulation was on the same or opposite side of the vertical meridian as the test spot. Test thresholds for a 1.5-deg diameter, 8-ms spot located 1.75 deg to one side of the vertical meridian were elevated by approximately 0.125 log units when a 0.25 cycles/deg (cpd) counterphased grating was presented at a similar eccentric offset on the other side of the vertical meridian. The periphery effect disappeared when the test spot was moved outward to 8-deg eccentricity. When the grating and test were presented on the same side of the vertical meridian, test thresholds at both retinal locations were elevated by the same amount, 0.2 log units. Consistent with the physiology in cat retina, the periphery effect in humans also crosses over the vertical meridian. However, the effect is small and the test spot must be in close proximity to the vertical meridian for it to be observed. Also, the crossover periphery effect is reduced in magnitude by 37.5% compared to when the grating and test are presented on the same side of the vertical meridian. This suggests there may be a difference in how the underlying neural mechanism that transmits the periphery effect signal laterally is organized for sending the periphery effect signal across the vertical meridian as compared to within a retinal hemifield.

Slumdog cities: rethinking subaltern urbanism.

PubMed

Roy, Ananya

2011-01-01

This article is an intervention in the epistemologies and methodologies of urban studies. It seeks to understand and transform the ways in which the cities of the global South are studied and represented in urban research, and to some extent in popular discourse. As such, the article is primarily concerned with a formation of ideas - "subaltern urbanism" - which undertakes the theorization of the megacity and its subaltern spaces and subaltern classes. Of these, the ubiquitous ‘slum’ is the most prominent. Writing against apocalyptic and dystopian narratives of the slum, subaltern urbanism provides accounts of the slum as a terrain of habitation, livelihood, self-organization and politics. This is a vital and even radical challenge to dominant narratives of the megacity. However, this article is concerned with the limits of and alternatives to subaltern urbanism. It thus highlights emergent analytical strategies, utilizing theoretical categories that transcend the familiar metonyms of underdevelopment such as the megacity, the slum, mass politics and the habitus of the dispossessed. Instead, four categories are discussed — peripheries, urban informality, zones of exception and gray spaces. Informed by the urbanism of the global South, these categories break with ontological and topological understandings of subaltern subjects and subaltern spaces.

An evaluation of spatial resolution of a prototype proton CT scanner.

PubMed

Plautz, Tia E; Bashkirov, V; Giacometti, V; Hurley, R F; Johnson, R P; Piersimoni, P; Sadrozinski, H F-W; Schulte, R W; Zatserklyaniy, A

2016-12-01

To evaluate the spatial resolution of proton CT using both a prototype proton CT scanner and Monte Carlo simulations. A custom cylindrical edge phantom containing twelve tissue-equivalent inserts with four different compositions at varying radial displacements from the axis of rotation was developed for measuring the modulation transfer function (MTF) of a prototype proton CT scanner. Two scans of the phantom, centered on the axis of rotation, were obtained with a 200 MeV, low-intensity proton beam: one scan with steps of 4°, and one scan with the phantom continuously rotating. In addition, Monte Carlo simulations of the phantom scan were performed using scanners idealized to various degrees. The data were reconstructed using an iterative projection method with added total variation superiorization based on individual proton histories. Edge spread functions in the radial and azimuthal directions were obtained using the oversampling technique. These were then used to obtain the modulation transfer functions. The spatial resolution was defined by the 10% value of the modulation transfer function (MTF 10% ) in units of line pairs per centimeter (lp/cm). Data from the simulations were used to better understand the contributions of multiple Coulomb scattering in the phantom and the scanner hardware, as well as the effect of discretization of proton location. The radial spatial resolution of the prototype proton CT scanner depends on the total path length, W, of the proton in the phantom, whereas the azimuthal spatial resolution depends both on W and the position, u - , at which the most-likely path uncertainty is evaluated along the path. For protons contributing to radial spatial resolution, W varies with the radial position of the edge, whereas for protons contributing to azimuthal spatial resolution, W is approximately constant. For a pixel size of 0.625 mm, the radial spatial resolution of the image reconstructed from the fully idealized simulation data ranged between 6.31 ± 0.36 lp/cm for W = 197 mm i.e., close to the center of the phantom, and 13.79 ± 0.36 lp/cm for W = 97 mm, near the periphery of the phantom. The azimuthal spatial resolution ranged from 6.99 ± 0.23 lp/cm at u - = 75 mm (near the center) to 11.20 ± 0.26 lp/cm at u - = 20 mm (near the periphery). Multiple Coulomb scattering limits the radial spatial resolution for path lengths greater than approximately 130 mm, and the azimuthal spatial resolution for positions of evaluation greater than approximately 40 mm for W = 199 mm. The radial spatial resolution of the image reconstructed from data from the 4° stepped experimental scan ranged from 5.11 ± 0.61 lp/cm for W = 197 mm to 8.58 ± 0.50 lp/cm for W = 97 mm. In the azimuthal direction, the spatial resolution ranged from 5.37 ± 0.40 lp/cm at u - = 75 mm to 7.27 ± 0.39 lp/cm at u - = 20 mm. The continuous scan achieved the same spatial resolution as that of the stepped scan. Multiple Coulomb scattering in the phantom is the limiting physical factor of the achievable spatial resolution of proton CT; additional loss of spatial resolution in the prototype system is associated with scattering in the proton tracking system and inadequacies of the proton path estimate used in the iterative reconstruction algorithm. Improvement in spatial resolution may be achievable by improving the most likely path estimate by incorporating information about high and low density materials, and by minimizing multiple Coulomb scattering in the proton tracking system.

An evaluation of spatial resolution of a prototype proton CT scanner

PubMed Central

Plautz, Tia E.; Bashkirov, V.; Giacometti, V.; Hurley, R. F.; Piersimoni, P.; Sadrozinski, H. F.-W.; Schulte, R. W.; Zatserklyaniy, A.

2016-01-01

Purpose: To evaluate the spatial resolution of proton CT using both a prototype proton CT scanner and Monte Carlo simulations. Methods: A custom cylindrical edge phantom containing twelve tissue-equivalent inserts with four different compositions at varying radial displacements from the axis of rotation was developed for measuring the modulation transfer function (MTF) of a prototype proton CT scanner. Two scans of the phantom, centered on the axis of rotation, were obtained with a 200 MeV, low-intensity proton beam: one scan with steps of 4°, and one scan with the phantom continuously rotating. In addition, Monte Carlo simulations of the phantom scan were performed using scanners idealized to various degrees. The data were reconstructed using an iterative projection method with added total variation superiorization based on individual proton histories. Edge spread functions in the radial and azimuthal directions were obtained using the oversampling technique. These were then used to obtain the modulation transfer functions. The spatial resolution was defined by the 10% value of the modulation transfer function (MTF10%) in units of line pairs per centimeter (lp/cm). Data from the simulations were used to better understand the contributions of multiple Coulomb scattering in the phantom and the scanner hardware, as well as the effect of discretization of proton location. Results: The radial spatial resolution of the prototype proton CT scanner depends on the total path length, W, of the proton in the phantom, whereas the azimuthal spatial resolution depends both on W and the position, u−, at which the most-likely path uncertainty is evaluated along the path. For protons contributing to radial spatial resolution, W varies with the radial position of the edge, whereas for protons contributing to azimuthal spatial resolution, W is approximately constant. For a pixel size of 0.625 mm, the radial spatial resolution of the image reconstructed from the fully idealized simulation data ranged between 6.31 ± 0.36 lp/cm for W = 197 mm i.e., close to the center of the phantom, and 13.79 ± 0.36 lp/cm for W = 97 mm, near the periphery of the phantom. The azimuthal spatial resolution ranged from 6.99 ± 0.23 lp/cm at u− = 75 mm (near the center) to 11.20 ± 0.26 lp/cm at u− = 20 mm (near the periphery). Multiple Coulomb scattering limits the radial spatial resolution for path lengths greater than approximately 130 mm, and the azimuthal spatial resolution for positions of evaluation greater than approximately 40 mm for W = 199 mm. The radial spatial resolution of the image reconstructed from data from the 4° stepped experimental scan ranged from 5.11 ± 0.61 lp/cm for W = 197 mm to 8.58 ± 0.50 lp/cm for W = 97 mm. In the azimuthal direction, the spatial resolution ranged from 5.37 ± 0.40 lp/cm at u− = 75 mm to 7.27 ± 0.39 lp/cm at u− = 20 mm. The continuous scan achieved the same spatial resolution as that of the stepped scan. Conclusions: Multiple Coulomb scattering in the phantom is the limiting physical factor of the achievable spatial resolution of proton CT; additional loss of spatial resolution in the prototype system is associated with scattering in the proton tracking system and inadequacies of the proton path estimate used in the iterative reconstruction algorithm. Improvement in spatial resolution may be achievable by improving the most likely path estimate by incorporating information about high and low density materials, and by minimizing multiple Coulomb scattering in the proton tracking system. PMID:27908179

Microstructure of the optic disc pit in open-angle glaucoma.

PubMed

Choi, Yun Jeong; Lee, Eun Ji; Kim, Bo Hyuk; Kim, Tae-Woo

2014-11-01

To investigate the structural and clinical characteristics of the optic disc pit (ODP) in primary open-angle glaucoma (POAG) via enhanced depth imaging (EDI) spectral-domain optical coherence tomography (SD-OCT). Prospective, observational case series. Seventy POAG eyes clinically diagnosed with an ODP via stereo disc photography. Optic discs were scanned using EDI SD-OCT. Serial horizontal and vertical B-scan images covering the optic discs were obtained from each eye. The structural characteristics of the ODP were investigated via 3-dimensional images constructed from the serial B-scans, focusing on the presence of alterations in the contour of the lamina cribrosa (LC) or prelaminar tissue (PLT), in conjunction with associated clinical characteristics. The structural characteristics of the ODP and associated clinical characteristics. In the EDI SD-OCT images, the ODP was viewed as an isolated alteration of the LC (n = 14, 20.0%) or PLT (n = 16, 22.9%) or an alteration of both the LC and PLT (n = 40, 57.1%). Alterations of the LC were located at the mid-periphery near the LC insertion (n = 17) or far periphery adjacent to the LC insertion (n = 37), and the depth of alteration was deep (n = 23), involving nearly full-thickness LC, or shallow (n = 31), with partially visible LC at the base. Fifty-four eyes (77.1%) exhibited parafoveal visual field (VF) defect within 10 degrees of fixation, and in 98.1% of these eyes (53/54) it was spatially associated with the location of ODP. The parafoveal VF defect was more prevalent in eyes with LC alteration than those without (83.3% vs. 56.2%, P = 0.023) and in eyes with deep LC defect than those with shallow defect (95.7% vs. 74.2%, P = 0.036). Disc hemorrhage (32.4% vs. 0.0%, P = 0.008) and peripapillary retinoschisis (18.9 vs. 0.0%, P = 0.055) were more strongly associated with LC alterations located at the far periphery than at the mid-periphery. Enhanced depth imaging SD-OCT facilitated visualization of the varied structure of the ODP, which presented as alteration of the LC or PLT or both. The clinical significance of differing characteristics of ODP microstructure remains to be determined. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Characterizing core-periphery structure of complex network by h-core and fingerprint curve

NASA Astrophysics Data System (ADS)

Li, Simon S.; Ye, Adam Y.; Qi, Eric P.; Stanley, H. Eugene; Ye, Fred Y.

2018-02-01

It is proposed that the core-periphery structure of complex networks can be simulated by h-cores and fingerprint curves. While the features of core structure are characterized by h-core, the features of periphery structure are visualized by rose or spiral curve as the fingerprint curve linking to entire-network parameters. It is suggested that a complex network can be approached by h-core and rose curves as the first-order Fourier-approach, where the core-periphery structure is characterized by five parameters: network h-index, network radius, degree power, network density and average clustering coefficient. The simulation looks Fourier-like analysis.

Core molecule dependence of energy migration in phenylacetylene nanostar dendrimers: Ab initio molecular orbital-configuration interaction based quantum master equation study

NASA Astrophysics Data System (ADS)

Kishi, Ryohei; Minami, Takuya; Fukui, Hitoshi; Takahashi, Hideaki; Nakano, Masayoshi

2008-06-01

The core molecule dependence of energy (exciton) migration in phenylacetylene nanostar dendrimers is investigated using the ab initio molecular orbital (MO)-configuration interaction based quantum master equation approach. We examine three kinds of core molecular species, i.e., benzene, anthracene, and pentacene, with different highest occupied MO-lowest unoccupied MO (HOMO-LUMO) gaps, which lead to different orbital interactions between the dendron parts and the core molecule. The nanostars bearing anthracene and pentacene cores are characterized by multistep exciton states with spatially well-segmented distributions: The exciton distributions of high-lying exciton states are spatially localized well in the periphery region, whereas those of low-lying exciton states are done in the core region. On the other hand, for the nanostar bearing benzene core, which also has multistep exciton states, the spatial exciton distributions of low-lying exciton states are delocalized over the dendron and the core regions. It is found that the former nanostars exhibit nearly complete exciton migration from the periphery to the core molecule in contrast to the latter one, in which significant exciton distribution remains in the dendron parts attached to the core after the exciton relaxation, although all these dendrimers exhibit fast exciton relaxation from the initially populated states. It is predicted from the analysis based on the MO correlation diagrams and the relative relaxation factor that the complete exciton migration to the core occurs not only when the HOMO-LUMO gap of the core molecule is nearly equal to that of the dendron parts attached to the core (anthracene case) but also when fairly smaller than that (pentacene case), whereas the complete migration is not achieved when the HOMO-LUMO gap of the core is larger than that of the dendron parts (benzene case). These results suggest that the fast and complete exciton migration of real dendrimers could be realized by adjusting the HOMO-LUMO gap of the core molecule to be smaller than that of dendron parts, although there exist more complicated relaxation processes as compared to simple dendritic aggregate models studied so far.

7-Hexagon Multifocal Electroretinography for an Objective Functional Assessment of the Macula in 14 Seconds.

PubMed

Schönbach, Etienne M; Chaikitmongkol, Voraporn; Annam, Rachel; McDonnell, Emma C; Wolfson, Yulia; Fletcher, Emily; Scholl, Hendrik P N

2017-01-01

We present the multifocal electroretinogram (mfERG) with a 7-hexagon array as an objective test of macular function that can be recorded in 14 s. We provide normal values and investigate its reproducibility and validity. Healthy participants underwent mfERG testing according to International Society for Clinical Electrophysiology of Vision (ISCEV) standards using the Espion Profile/D310 multifocal ERG system (Diagnosys, LLC, Lowell, MA, USA). One standard recording of a 61-hexagon array and 2 repeated recordings of a custom 7-hexagon array were obtained. A total of 13 subjects (mean age 46.9 years) were included. The median response densities were 12.5 nV/deg2 in the center and 5.2 nV/deg2 in the periphery. Intereye correlations were strong in both the center (ρCenter = 0.821; p < 0.0001) and the periphery (ρPeriphery = 0.862; p < 0.0001). Intraeye correlations were even stronger: ρCenter = 0.904 with p < 0.0001 and ρPeriphery = 0.955 with p < 0.0001. Bland-Altman plots demonstrated an acceptable retest mean difference in both the center and periphery, and narrow limits of agreement. We found strong correlations of the center (ρCenter = 0.826; p < 0.0001) and periphery (ρPeriphery = 0.848; p < 0.0001), with recordings obtained by the 61-hexagon method. The 7-hexagon mfERG provides reproducible results in agreement with results obtained according to the ISCEV standard. © 2017 S. Karger AG, Basel.

Extended experience benefits spatial mental model development with route but not survey descriptions.

PubMed

Brunyé, Tad T; Taylor, Holly A

2008-02-01

Spatial descriptions symbolically represent environmental information through language and are written in two primary perspectives: survey, analogous to viewing a map, and route, analogous to navigation. Readers of survey or route descriptions form abstracted perspective flexible representations of the described environment, or spatial mental models. The present two experiments investigated the maintenance of perspective in spatial mental models as a function of description perspective and experience (operationalized through repetition), and as reflected in self-paced reading times. Experiment 1 involved studying survey and route descriptions either once or three times, then completing map drawing and true/false statement verification. Results demonstrated that spatial mental models are readily formed with survey descriptions, but require relatively more experience with route descriptions; further, some limited evidence suggests perspective dependence in spatial mental models, even following extended experience. Experiment 2 measured self-paced reading during three successive description presentations. Average reading times over the three presentations reduced more for survey relative to route descriptions, and there was no evidence for perspective specificity in resulting spatial mental models. This supports Experiment 1 findings demonstrating the relatively time-consuming nature of acquiring spatial mental models from route, but not survey descriptions. Results are discussed with regard to developmental, discourse processing, and spatial mental model theory.

Relationships Among Peripheral and Central Electrophysiological Measures of Spatial and Spectral Selectivity and Speech Perception in Cochlear Implant Users.

PubMed

Scheperle, Rachel A; Abbas, Paul J

2015-01-01

The ability to perceive speech is related to the listener's ability to differentiate among frequencies (i.e., spectral resolution). Cochlear implant (CI) users exhibit variable speech-perception and spectral-resolution abilities, which can be attributed in part to the extent of electrode interactions at the periphery (i.e., spatial selectivity). However, electrophysiological measures of peripheral spatial selectivity have not been found to correlate with speech perception. The purpose of this study was to evaluate auditory processing at the periphery and cortex using both simple and spectrally complex stimuli to better understand the stages of neural processing underlying speech perception. The hypotheses were that (1) by more completely characterizing peripheral excitation patterns than in previous studies, significant correlations with measures of spectral selectivity and speech perception would be observed, (2) adding information about processing at a level central to the auditory nerve would account for additional variability in speech perception, and (3) responses elicited with spectrally complex stimuli would be more strongly correlated with speech perception than responses elicited with spectrally simple stimuli. Eleven adult CI users participated. Three experimental processor programs (MAPs) were created to vary the likelihood of electrode interactions within each participant. For each MAP, a subset of 7 of 22 intracochlear electrodes was activated: adjacent (MAP 1), every other (MAP 2), or every third (MAP 3). Peripheral spatial selectivity was assessed using the electrically evoked compound action potential (ECAP) to obtain channel-interaction functions for all activated electrodes (13 functions total). Central processing was assessed by eliciting the auditory change complex with both spatial (electrode pairs) and spectral (rippled noise) stimulus changes. Speech-perception measures included vowel discrimination and the Bamford-Kowal-Bench Speech-in-Noise test. Spatial and spectral selectivity and speech perception were expected to be poorest with MAP 1 (closest electrode spacing) and best with MAP 3 (widest electrode spacing). Relationships among the electrophysiological and speech-perception measures were evaluated using mixed-model and simple linear regression analyses. All electrophysiological measures were significantly correlated with each other and with speech scores for the mixed-model analysis, which takes into account multiple measures per person (i.e., experimental MAPs). The ECAP measures were the best predictor. In the simple linear regression analysis on MAP 3 data, only the cortical measures were significantly correlated with speech scores; spectral auditory change complex amplitude was the strongest predictor. The results suggest that both peripheral and central electrophysiological measures of spatial and spectral selectivity provide valuable information about speech perception. Clinically, it is often desirable to optimize performance for individual CI users. These results suggest that ECAP measures may be most useful for within-subject applications when multiple measures are performed to make decisions about processor options. They also suggest that if the goal is to compare performance across individuals based on a single measure, then processing central to the auditory nerve (specifically, cortical measures of discriminability) should be considered.

High-spatial-resolution mapping of catalytic reactions on single particles

DOE PAGES

Wu, Chung-Yeh; Wolf, William J.; Levartovsky, Yehonatan; ...

2017-01-26

We report the critical role in surface reactions and heterogeneous catalysis of metal atoms with low coordination numbers, such as found at atomic steps and surface defects, is firmly established. But despite the growing availability of tools that enable detailed in situ characterization, so far it has not been possible to document this role directly. Surface properties can be mapped with high spatial resolution, and catalytic conversion can be tracked with a clear chemical signature; however, the combination of the two, which would enable high-spatial-resolution detection of reactions on catalytic surfaces, has rarely been achieved. Single-molecule fluorescence spectroscopy has beenmore » used to image and characterize single turnover sites at catalytic surfaces, but is restricted to reactions that generate highly fluorescing product molecules. Herein the chemical conversion of N-heterocyclic carbene molecules attached to catalytic particles is mapped using synchrotron-radiation-based infrared nanospectroscopy with a spatial resolution of 25 nanometres, which enabled particle regions that differ in reactivity to be distinguished. Lastly, these observations demonstrate that, compared to the flat regions on top of the particles, the peripheries of the particles-which contain metal atoms with low coordination numbers-are more active in catalysing oxidation and reduction of chemically active groups in surface-anchored N-heterocyclic carbene molecules.« less

Traces of Old and New Center-Periphery Dynamics in Language-in-Education Policy and Practice: Insights from a Linguistic Ethnographic Study in Timor-Leste

ERIC Educational Resources Information Center

Da Costa Cabral, Ildegrada; Martin-Jones, Marilyn

2017-01-01

This article reveals how center-periphery relations have unfolded, over time, in language policy processes in one nation--Timor-Leste--on the global periphery. We take a "longue durée" perspective on the language policy processes at work in this historical context, showing how different regimes of language were imposed, in the past, by…

The role of spatial dynamics in modulating metabolic interactions in biofilm development

NASA Astrophysics Data System (ADS)

Bocci, Federico; Lu, Mingyang; Suzuki, Yoko; Onuchic, Jose

Cell phenotypic expression is substantially affected by the presence of environmental stresses and cell-cell communication mechanisms. We study the metabolic interactions of the glutamate synthesis pathway to explain the oscillation of growth rate observed in a B. Subtilis colony. Previous modelling schemes had failed in fully reproducing quantitative experimental observations as they did not explicitly address neither the diffusion of small metabolites nor the spatial distribution of phenotypically distinct bacteria inside the colony. We introduce a continuous space-temporal framework to explain how biofilm development dynamics is influenced by the metabolic interplay between two bacterial phenotypes composing the interior and the peripheral layer of the biofilm. Growth oscillations endorse the preservation of a high level of nutrients in the interior through diffusion and colony expansion in the periphery altogether. Our findings point out that perturbations of environmental conditions can result in the interruption of the interplay between cell populations and advocate alternative approaches to biofilm control strategies.

Visible Contrast Energy Metrics for Detection and Discrimination

NASA Technical Reports Server (NTRS)

Ahumada, Albert; Watson, Andrew

2013-01-01

Contrast energy was proposed by Watson, Robson, & Barlow as a useful metric for representing luminance contrast target stimuli because it represents the detectability of the stimulus in photon noise for an ideal observer. Like the eye, the ear is a complex transducer system, but relatively simple sound level meters are used to characterize sounds. These meters provide a range of frequency sensitivity functions and integration times depending on the intended use. We propose here the use of a range of contrast energy measures with different spatial frequency contrast sensitivity weightings, eccentricity sensitivity weightings, and temporal integration times. When detection threshold are plotting using such measures, the results show what the eye sees best when these variables are taken into account in a standard way. The suggested weighting functions revise the Standard Spatial Observer for luminance contrast detection and extend it into the near periphery. Under the assumption that the detection is limited only by internal noise, discrimination performance can be predicted by metrics based on the visible energy of the difference images

Drosophila germ granules are structured and contain homotypic mRNA clusters

PubMed Central

Trcek, Tatjana; Grosch, Markus; York, Andrew; Shroff, Hari; Lionnet, Timothée; Lehmann, Ruth

2015-01-01

Germ granules, specialized ribonucleoprotein particles, are a hallmark of all germ cells. In Drosophila, an estimated 200 mRNAs are enriched in the germ plasm, and some of these have important, often conserved roles in germ cell formation, specification, survival and migration. How mRNAs are spatially distributed within a germ granule and whether their position defines functional properties is unclear. Here we show, using single-molecule FISH and structured illumination microscopy, a super-resolution approach, that mRNAs are spatially organized within the granule whereas core germ plasm proteins are distributed evenly throughout the granule. Multiple copies of single mRNAs organize into ‘homotypic clusters' that occupy defined positions within the center or periphery of the granule. This organization, which is maintained during embryogenesis and independent of the translational or degradation activity of mRNAs, reveals new regulatory mechanisms for germ plasm mRNAs that may be applicable to other mRNA granules. PMID:26242323

Statistics for characterizing data on the periphery

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

Theiler, James P; Hush, Donald R

2010-01-01

We introduce a class of statistics for characterizing the periphery of a distribution, and show that these statistics are particularly valuable for problems in target detection. Because so many detection algorithms are rooted in Gaussian statistics, we concentrate on ellipsoidal models of high-dimensional data distributions (that is to say: covariance matrices), but we recommend several alternatives to the sample covariance matrix that more efficiently model the periphery of a distribution, and can more effectively detect anomalous data samples.

Interacting effects of latitude, mass, age, and sex on winter survival of Surf Scoters (Melanitta perspicillata): Implications for differential migration

USGS Publications Warehouse

Uher-Koch, Brian D.; Esler, Daniel N.; Iverson, Samuel A.; Ward, David; Boyd, Sean; Kirk, Molly; Lewis, Tyler L.; VanStratt, Corey S.; Brodhead, Katherine M.; Hupp, Jerry W.; Schmutz, Joel A.

2016-01-01

We quantified variation in winter survival of Surf Scoters (Melanitta perspicillata (L., 1758)) across nearly 30° of latitude on the Pacific coast of North America to evaluate potential effects on winter distributions, including observed differential distributions of age and sex classes. We monitored fates of 297 radio-marked Surf Scoters at three study sites: (1) near the northern periphery of their wintering range in southeast Alaska, USA, (2) the range core in British Columbia, Canada, and (3) the southern periphery in Baja California, Mexico. We detected 34 mortalities and determined that survival averaged lower at the range peripheries than in the range core, was lower during mid-winter than during late winter at all sites, and was positively correlated with body mass within locations. Although neither age nor sex class had direct effects, mass effects led to differential survival patterns among classes. When simultaneously incorporating these interacting influences, adult males of mean mass for their location had highest survival at the northern range periphery in Alaska, whereas adult females and juveniles had higher survival at the range core and the southern periphery. Our observations help to explain patterns of differential migration and distribution reported for this species and highlight seasonal periods (mid-winter) and locations (range peripheries) of elevated levels of mortality for demographically important age–sex classes (adult females).

Learning to identify crowded letters: Does the learning depend on the frequency of training?

PubMed Central

Chung, Susana T. L.; Truong, Sandy R.

2012-01-01

Performance for many visual tasks improves with training. The magnitude of improvement following training depends on the training task, number of trials per training session and the total amount of training. Does the magnitude of improvement also depend on the frequency of training sessions? In this study, we compared the learning effect for three groups of normally sighted observers who repeatedly practiced the task of identifying crowded letters in the periphery for six sessions (1000 trials per session), according to three different training schedules — one group received one session of training everyday, the second group received a training session once a week and the third group once every two weeks. Following six sessions of training, all observers improved in their performance of identifying crowded letters in the periphery. Most importantly, the magnitudes of improvement were similar across the three training groups. The improvement was accompanied by a reduction in the spatial extent of crowding, an increase in the size of visual span and a reduction in letter-size threshold. The magnitudes of these accompanied improvements were also similar across the three training groups. Our finding that the effectiveness of visual perceptual learning is similar for daily, weekly and biweekly training has significant implication for adopting perceptual learning as an option to improve visual functions for clinical patients. PMID:23206551

Dynamics and three-dimensional localization of ribosomal RNA within the nucleolus.

PubMed Central

Thiry, M; Cheutin, T; O'Donohue, M F; Kaplan, H; Ploton, D

2000-01-01

Although rRNA synthesis, maturation, and assembly into preribosomal particles occur within the nucleolus, the route taken by pre-rRNAs from their synthetic sites toward the cytoplasm remains largely unexplored. Here, we employed a nondestructive method for the incorporation of BrUTP into the RNA of living cells. By using pulse-chase experiments, three-dimensional image reconstructions of confocal optical sections, and electron microscopy analysis of ultrathin sections, we were able to describe topological and spatial dynamics of rRNAs within the nucleolus. We identified the precise location and the volumic organization of four typical subdomains, in which rRNAs are successively moving towards the nucleolar periphery during their synthesis and processing steps. The incorporation of BrUTP takes place simultaneously within several tiny spheres, centered on the fibrillar centers. Then, the structures containing the newly synthesized RNAs enlarge and appear as compact ringlets disposed around the fibrillar centers. Later, they form hollow spheres surrounding the latter components and begin to fuse together. Finally, these structures widen and form large rings reaching the limits of the nucleoli. These results clearly show that the transport of pre-rRNAs within the nucleolus does not occur randomly, but appears as a radial flow starting from the fibrillar centers that form concentric rings, which finally fuse together as they progress toward the nucleolar periphery. PMID:11142375

Iconic Gestures Facilitate Discourse Comprehension in Individuals With Superior Immediate Memory for Body Configurations.

PubMed

Wu, Ying Choon; Coulson, Seana

2015-11-01

To understand a speaker's gestures, people may draw on kinesthetic working memory (KWM)-a system for temporarily remembering body movements. The present study explored whether sensitivity to gesture meaning was related to differences in KWM capacity. KWM was evaluated through sequences of novel movements that participants viewed and reproduced with their own bodies. Gesture sensitivity was assessed through a priming paradigm. Participants judged whether multimodal utterances containing congruent, incongruent, or no gestures were related to subsequent picture probes depicting the referents of those utterances. Individuals with low KWM were primarily inhibited by incongruent speech-gesture primes, whereas those with high KWM showed facilitation-that is, they were able to identify picture probes more quickly when preceded by congruent speech and gestures than by speech alone. Group differences were most apparent for discourse with weakly congruent speech and gestures. Overall, speech-gesture congruency effects were positively correlated with KWM abilities, which may help listeners match spatial properties of gestures to concepts evoked by speech. © The Author(s) 2015.

Benevolent technotopias and hitherto unimaginable meats: Tracing the promises of in vitro meat.

PubMed

Jönsson, Erik

2016-10-01

Today, in vitro (Latin: in glass) meat researchers strive to overhaul meat production technologies by producing meat outside animal bodies, primarily by culturing cells. In the process, meat should become healthier, more environmentally friendly and kinder to animals. In this article, I scrutinize (and problematize) this promissory discourse by examining the world that proponents envision alongside the world from which promises emerge. First, I trace the increasing number of publications striving to pinpoint the nature of in vitro meat to unveil the creation of an in vitro meat canon wherein perceived possibilities become taken for granted. Second, I investigate how the promissory discourse is often relatively silent on key aspects of how this technology could remake the world. Wet laboratories, animals and end products become foregrounded at the expense of political economy and the biophysical properties of cultured cells. Thus, questions concerning how funding requirements shape representations of this new technology, together with in vitro meat's particular socio-spatial and socio-ecological implications, become problematically de-emphasized.

Envisioning the Third Sector's Welfare Role: Critical Discourse Analysis of ‘Post-Devolution’ Public Policy in the UK 1998–2012

PubMed Central

Chaney, Paul; Wincott, Daniel

2014-01-01

Welfare state theory has struggled to come to terms with the role of the third sector. It has often categorized welfare states in terms of the pattern of interplay between state social policies and the structure of the labour market. Moreover, it has frequently offered an exclusive focus on state policy – thereby failing to substantially recognize the role of the formally organized third sector. This study offers a corrective view. Against the backdrop of the international shift to multi-level governance, it analyses the policy discourse of third sector involvement in welfare governance following devolution in the UK. It reveals the changing and contrasting ways in which post-devolution territorial politics envisions the sector's role as a welfare provider. The mixed methods analysis compares policy framing and the structural narratives associated with the development of the third sector across the four constituent polities of the UK since 1998. The findings reveal how devolution has introduced a new spatial policy dynamic. Whilst there are elements of continuity between polities – such as the increasing salience of the third sector in welfare provision – policy narratives also provide evidence of the territorialization of third sector policy. From a methodological standpoint, this underlines the distinctive and complementary role discourse-based analysis can play in understanding contemporary patterns and processes shaping welfare governance. PMID:25574063

Envisioning the Third Sector's Welfare Role: Critical Discourse Analysis of 'Post-Devolution' Public Policy in the UK 1998-2012.

PubMed

Chaney, Paul; Wincott, Daniel

2014-12-01

Welfare state theory has struggled to come to terms with the role of the third sector. It has often categorized welfare states in terms of the pattern of interplay between state social policies and the structure of the labour market. Moreover, it has frequently offered an exclusive focus on state policy - thereby failing to substantially recognize the role of the formally organized third sector. This study offers a corrective view. Against the backdrop of the international shift to multi-level governance, it analyses the policy discourse of third sector involvement in welfare governance following devolution in the UK. It reveals the changing and contrasting ways in which post-devolution territorial politics envisions the sector's role as a welfare provider. The mixed methods analysis compares policy framing and the structural narratives associated with the development of the third sector across the four constituent polities of the UK since 1998. The findings reveal how devolution has introduced a new spatial policy dynamic. Whilst there are elements of continuity between polities - such as the increasing salience of the third sector in welfare provision - policy narratives also provide evidence of the territorialization of third sector policy. From a methodological standpoint, this underlines the distinctive and complementary role discourse-based analysis can play in understanding contemporary patterns and processes shaping welfare governance.

Relationships Among Peripheral and Central Electrophysiological Measures of Spatial and Spectral Selectivity and Speech Perception in Cochlear Implant Users

PubMed Central

Scheperle, Rachel A.; Abbas, Paul J.

2014-01-01

Objectives The ability to perceive speech is related to the listener’s ability to differentiate among frequencies (i.e., spectral resolution). Cochlear implant (CI) users exhibit variable speech-perception and spectral-resolution abilities, which can be attributed in part to the extent of electrode interactions at the periphery (i.e., spatial selectivity). However, electrophysiological measures of peripheral spatial selectivity have not been found to correlate with speech perception. The purpose of this study was to evaluate auditory processing at the periphery and cortex using both simple and spectrally complex stimuli to better understand the stages of neural processing underlying speech perception. The hypotheses were that (1) by more completely characterizing peripheral excitation patterns than in previous studies, significant correlations with measures of spectral selectivity and speech perception would be observed, (2) adding information about processing at a level central to the auditory nerve would account for additional variability in speech perception, and (3) responses elicited with spectrally complex stimuli would be more strongly correlated with speech perception than responses elicited with spectrally simple stimuli. Design Eleven adult CI users participated. Three experimental processor programs (MAPs) were created to vary the likelihood of electrode interactions within each participant. For each MAP, a subset of 7 of 22 intracochlear electrodes was activated: adjacent (MAP 1), every-other (MAP 2), or every third (MAP 3). Peripheral spatial selectivity was assessed using the electrically evoked compound action potential (ECAP) to obtain channel-interaction functions for all activated electrodes (13 functions total). Central processing was assessed by eliciting the auditory change complex (ACC) with both spatial (electrode pairs) and spectral (rippled noise) stimulus changes. Speech-perception measures included vowel-discrimination and the Bamford-Kowal-Bench Sentence-in-Noise (BKB-SIN) test. Spatial and spectral selectivity and speech perception were expected to be poorest with MAP 1 (closest electrode spacing) and best with MAP 3 (widest electrode spacing). Relationships among the electrophysiological and speech-perception measures were evaluated using mixed-model and simple linear regression analyses. Results All electrophysiological measures were significantly correlated with each other and with speech perception for the mixed-model analysis, which takes into account multiple measures per person (i.e. experimental MAPs). The ECAP measures were the best predictor of speech perception. In the simple linear regression analysis on MAP 3 data, only the cortical measures were significantly correlated with speech; spectral ACC amplitude was the strongest predictor. Conclusions The results suggest that both peripheral and central electrophysiological measures of spatial and spectral selectivity provide valuable information about speech perception. Clinically, it is often desirable to optimize performance for individual CI users. These results suggest that ECAP measures may be the most useful for within-subject applications, when multiple measures are performed to make decisions about processor options. They also suggest that if the goal is to compare performance across individuals based on single measure, then processing central to the auditory nerve (specifically, cortical measures of discriminability) should be considered. PMID:25658746

Visual spatial attention enhances the amplitude of positive and negative fMRI responses to visual stimulation in an eccentricity-dependent manner

PubMed Central

Bressler, David W.; Fortenbaugh, Francesca C.; Robertson, Lynn C.; Silver, Michael A.

2013-01-01

Endogenous visual spatial attention improves perception and enhances neural responses to visual stimuli at attended locations. Although many aspects of visual processing differ significantly between central and peripheral vision, little is known regarding the neural substrates of the eccentricity dependence of spatial attention effects. We measured amplitudes of positive and negative fMRI responses to visual stimuli as a function of eccentricity in a large number of topographically-organized cortical areas. Responses to each stimulus were obtained when the stimulus was attended and when spatial attention was directed to a stimulus in the opposite visual hemifield. Attending to the stimulus increased both positive and negative response amplitudes in all cortical areas we studied: V1, V2, V3, hV4, VO1, LO1, LO2, V3A/B, IPS0, TO1, and TO2. However, the eccentricity dependence of these effects differed considerably across cortical areas. In early visual, ventral, and lateral occipital cortex, attentional enhancement of positive responses was greater for central compared to peripheral eccentricities. The opposite pattern was observed in dorsal stream areas IPS0 and putative MT homolog TO1, where attentional enhancement of positive responses was greater in the periphery. Both the magnitude and the eccentricity dependence of attentional modulation of negative fMRI responses closely mirrored that of positive responses across cortical areas. PMID:23562388

Mosaic evolution of the mammalian auditory periphery.

PubMed

Manley, Geoffrey A

2013-01-01

The classical mammalian auditory periphery, i.e., the type of middle ear and coiled cochlea seen in modern therian mammals, did not arise as one unit and did not arise in all mammals. It is also not the only kind of auditory periphery seen in modern mammals. This short review discusses the fact that the constituents of modern mammalian auditory peripheries arose at different times over an extremely long period of evolution (230 million years; Ma). It also attempts to answer questions as to the selective pressures that led to three-ossicle middle ears and the coiled cochlea. Mammalian middle ears arose de novo, without an intermediate, single-ossicle stage. This event was the result of changes in eating habits of ancestral animals, habits that were unrelated to hearing. The coiled cochlea arose only after 60 Ma of mammalian evolution, driven at least partly by a change in cochlear bone structure that improved impedance matching with the middle ear of that time. This change only occurred in the ancestors of therian mammals and not in other mammalian lineages. There is no single constellation of structural features of the auditory periphery that characterizes all mammals and not even all modern mammals.

Dopant radial inhomogeneity in Mg-doped GaN nanowires.

PubMed

Siladie, Alexandra-Madalina; Amichi, Lynda; Mollard, Nicolas; Mouton, Isabelle; Bonef, Bastien; Bougerol, Catherine; Grenier, Adeline; Robin, Eric; Jouneau, Pierre-Henri; Garro, Nuria; Cros, Ana; Daudin, Bruno

2018-06-22

Using atom probe tomography, it is demonstrated that Mg doping of GaN nanowires grown by Molecular Beam Epitaxy results in a marked radial inhomogeneity, namely a higher Mg content in the periphery of the nanowires. This spatial inhomogeneity is attributed to a preferential incorporation of Mg through the m-plane sidewalls of nanowires and is related to the formation of a Mg-rich surface which is stabilized by hydrogen. This is further supported by Raman spectroscopy experiments which give evidence of Mg-H complexes in the doped nanowires. A Mg doping mechanism such as this, specific to nanowires, may lead to higher levels of Mg doping than in layers, boosting the potential interest of nanowires for light emitting diode applications.

NONLINEAR AND FIBER OPTICS: Transverse traveling pulses in bistable interferometers with competing nonlinearities

NASA Astrophysics Data System (ADS)

Rzhanov, Yu A.; Grigor'yants, A. V.; Balkareĭ, Yu I.; Elinson, M. I.

1990-04-01

A detailed qualitative description is given of the formation and propagation of leading edges of transverse traveling pulses in a bistable semiconductor interferometer with competing concentration and thermal mechanisms of nonlinear refraction. It is shown that, depending on the laser pumping rate and the heat transfer conditions, two types of traveling pulses may exist with elevated and reduced transmission. Each of these may be initiated by a local change in the input intensity of any sign. When the interferometer is pumped by a spatially inhomogeneous, (for example, Gaussian) beam, periodic spontaneous initiation of both types of traveling pulses may take place at the periphery or in the center of a beam. Traveling pulses are modeled numerically under various interferometer pumping conditions.

Dopant radial inhomogeneity in Mg-doped GaN nanowires

NASA Astrophysics Data System (ADS)

Siladie, Alexandra-Madalina; Amichi, Lynda; Mollard, Nicolas; Mouton, Isabelle; Bonef, Bastien; Bougerol, Catherine; Grenier, Adeline; Robin, Eric; Jouneau, Pierre-Henri; Garro, Nuria; Cros, Ana; Daudin, Bruno

2018-06-01

Using atom probe tomography, it is demonstrated that Mg doping of GaN nanowires grown by Molecular Beam Epitaxy results in a marked radial inhomogeneity, namely a higher Mg content in the periphery of the nanowires. This spatial inhomogeneity is attributed to a preferential incorporation of Mg through the m-plane sidewalls of nanowires and is related to the formation of a Mg-rich surface which is stabilized by hydrogen. This is further supported by Raman spectroscopy experiments which give evidence of Mg-H complexes in the doped nanowires. A Mg doping mechanism such as this, specific to nanowires, may lead to higher levels of Mg doping than in layers, boosting the potential interest of nanowires for light emitting diode applications.

Information transfer rate with serial and simultaneous visual display formats

NASA Astrophysics Data System (ADS)

Matin, Ethel; Boff, Kenneth R.

1988-04-01

Information communication rate for a conventional display with three spatially separated windows was compared with rate for a serial display in which data frames were presented sequentially in one window. For both methods, each frame contained a randomly selected digit with various amounts of additional display 'clutter.' Subjects recalled the digits in a prescribed order. Large rate differences were found, with faster serial communication for all levels of the clutter factors. However, the rate difference was most pronounced for highly cluttered displays. An explanation for the latter effect in terms of visual masking in the retinal periphery was supported by the results of a second experiment. The working hypothesis that serial displays can speed information transfer for automatic but not for controlled processing is discussed.

Method and apparatus for wind turbine air gap control

DOEpatents

Grant, James Jonathan; Bagepalli, Bharat Sampathkumaran; Jansen, Patrick Lee; DiMascio, Paul Stephen; Gadre, Aniruddha Dattatraya; Qu, Ronghai

2007-02-20

Methods and apparatus for assembling a wind turbine generator are provided. The wind turbine generator includes a core and a plurality of stator windings circumferentially spaced about a generator longitudinal axis, a rotor rotatable about the generator longitudinal axis wherein the rotor includes a plurality of magnetic elements coupled to a radially outer periphery of the rotor such that an airgap is defined between the stator windings and the magnetic elements and the plurality of magnetic elements including a radially inner periphery having a first diameter. The wind turbine generator also includes a bearing including a first member in rotatable engagement with a radially inner second member, the first member including a radially outer periphery, a diameter of the radially outer periphery of the first member being substantially equal to the first diameter, the rotor coupled to the stator through the bearing such that a substantially uniform airgap is maintained.

New perspectives on occupational health and safety in immigrant populations: studying the intersection between immigrant background and gender.

PubMed

Mousaid, Sarah; De Moortel, Deborah; Malmusi, Davide; Vanroelen, Christophe

2016-01-01

Few studies investigating health inequalities pay attention to the intersection between several social determinants of health. The purpose of this article is to examine the relation between perceptions of work-related health and safety risk (WHSR) and (1) immigrant background and (2) gender in the EU-15. The effects are controlled for educational attainment, the quality of work (QOW) and occupation. Pooled data from the European Social Survey 2004 and 2010 are used in this study. The sample is restricted to respondents of working age (16-65 years) (N = 17,468). The immigrants are divided into two groups according to their country of origin: (semi-)periphery and core countries. Both groups of immigrants are compared to natives. Additionally, the research population is stratified by gender. Descriptive statistics and logistic regression analyses are used. Core immigrants (both men and women) do not differ from natives in terms of QOW. (Semi-)periphery immigrants (both men and women) are employed in jobs with lower QOW. While no differences in WHSR are found among men, female immigrants (both (semi-)periphery and core) have significantly more WHSR compared to native women. Although WHSR is generally lower in women, (semi-)periphery women have a similar prevalence of WHSR as men. (Semi-)periphery immigrants are employed in lower quality jobs, while core immigrants do not differ from natives in that regard. Female immigrant workers--especially those from (semi-)periphery countries--have higher WHSR compared to native women. Our findings highlight the importance of an intersectional approach in the study of work-related health inequalities.

Nonmydriatic fluorescence-based quantitative imaging of human macular pigment distributions

NASA Astrophysics Data System (ADS)

Sharifzadeh, Mohsen; Bernstein, Paul S.; Gellermann, Werner

2006-10-01

We have developed a CCD-camera-based nonmydriatic instrument that detects fluorescence from retinal lipofuscin chromophores ("autofluorescence") as a means to indirectly quantify and spatially image the distribution of macular pigment (MP). The lipofuscin fluorescence intensity is reduced at all retinal locations containing MP, since MP has a competing absorption in the blue-green wavelength region. Projecting a large diameter, 488 nm excitation spot onto the retina, centered on the fovea, but extending into the macular periphery, and comparing lipofuscin fluorescence intensities outside and inside the foveal area, it is possible to spatially map out the distribution of MP. Spectrally selective detection of the lipofuscin fluorescence reveals an important wavelength dependence of the obtainable image contrast and deduced MP optical density levels, showing that it is important to block out interfering fluorescence contributions in the detection setup originating from ocular media such as the lens. Measuring 70 healthy human volunteer subjects with no ocular pathologies, we find widely varying spatial extent of MP, distinctly differing distribution patterns of MP, and strongly differing absolute MP levels among individuals. Our population study suggests that MP imaging based on lipofuscin fluorescence is useful as a relatively simple, objective, and quantitative noninvasive optical technique suitable to rapidly screen MP levels and distributions in healthy humans with undilated pupils.

Spatial organization of the cytoskeleton enhances cargo delivery to specific target areas on the plasma membrane of spherical cells.

PubMed

Hafner, Anne E; Rieger, Heiko

2016-11-15

Intracellular transport is vital for the proper functioning and survival of a cell. Cargo (proteins, vesicles, organelles, etc) is transferred from its place of creation to its target locations via molecular motor assisted transport along cytoskeletal filaments. The transport efficiency is strongly affected by the spatial organization of the cytoskeleton, which constitutes an inhomogeneous, complex network. In cells with a centrosome microtubules grow radially from the central microtubule organizing center towards the cell periphery whereas actin filaments form a dense meshwork, the actin cortex, underneath the cell membrane with a broad range of orientations. The emerging ballistic motion along filaments is frequently interrupted due to constricting intersection nodes or cycles of detachment and reattachment processes in the crowded cytoplasm. In order to investigate the efficiency of search strategies established by the cell's specific spatial organization of the cytoskeleton we formulate a random velocity model with intermittent arrest states. With extensive computer simulations we analyze the dependence of the mean first passage times for narrow escape problems on the structural characteristics of the cytoskeleton, the motor properties and the fraction of time spent in each state. We find that an inhomogeneous architecture with a small width of the actin cortex constitutes an efficient intracellular search strategy.

Water quality modeling in the dead end sections of drinking water (Supplement)

EPA Pesticide Factsheets

Dead-end sections of drinking water distribution networks are known to be problematic zones in terms of water quality degradation. Extended residence time due to water stagnation leads to rapid reduction of disinfectant residuals allowing the regrowth of microbial pathogens. Water quality models developed so far apply spatial aggregation and temporal averaging techniques for hydraulic parameters by assigning hourly averaged water demands to the main nodes of the network. Although this practice has generally resulted in minimal loss of accuracy for the predicted disinfectant concentrations in main water transmission lines, this is not the case for the peripheries of the distribution network. This study proposes a new approach for simulating disinfectant residuals in dead end pipes while accounting for both spatial and temporal variability in hydraulic and transport parameters. A stochastic demand generator was developed to represent residential water pulses based on a non-homogenous Poisson process. Dispersive solute transport was considered using highly dynamic dispersion rates. A genetic algorithm was used tocalibrate the axial hydraulic profile of the dead-end pipe based on the different demand shares of the withdrawal nodes. A parametric sensitivity analysis was done to assess the model performance under variation of different simulation parameters. A group of Monte-Carlo ensembles was carried out to investigate the influence of spatial and temporal variation

Water Quality Modeling in the Dead End Sections of Drinking ...

EPA Pesticide Factsheets

Dead-end sections of drinking water distribution networks are known to be problematic zones in terms of water quality degradation. Extended residence time due to water stagnation leads to rapid reduction of disinfectant residuals allowing the regrowth of microbial pathogens. Water quality models developed so far apply spatial aggregation and temporal averaging techniques for hydraulic parameters by assigning hourly averaged water demands to the main nodes of the network. Although this practice has generally resulted in minimal loss of accuracy for the predicted disinfectant concentrations in main water transmission lines, this is not the case for the peripheries of a distribution network. This study proposes a new approach for simulating disinfectant residuals in dead end pipes while accounting for both spatial and temporal variability in hydraulic and transport parameters. A stochastic demand generator was developed to represent residential water pulses based on a non-homogenous Poisson process. Dispersive solute transport was considered using highly dynamic dispersion rates. A genetic algorithm was used to calibrate the axial hydraulic profile of the dead-end pipe based on the different demand shares of the withdrawal nodes. A parametric sensitivity analysis was done to assess the model performance under variation of different simulation parameters. A group of Monte-Carlo ensembles was carried out to investigate the influence of spatial and temporal variations

Spatial organization of the cytoskeleton enhances cargo delivery to specific target areas on the plasma membrane of spherical cells

NASA Astrophysics Data System (ADS)

Hafner, Anne E.; Rieger, Heiko

2016-12-01

Intracellular transport is vital for the proper functioning and survival of a cell. Cargo (proteins, vesicles, organelles, etc) is transferred from its place of creation to its target locations via molecular motor assisted transport along cytoskeletal filaments. The transport efficiency is strongly affected by the spatial organization of the cytoskeleton, which constitutes an inhomogeneous, complex network. In cells with a centrosome microtubules grow radially from the central microtubule organizing center towards the cell periphery whereas actin filaments form a dense meshwork, the actin cortex, underneath the cell membrane with a broad range of orientations. The emerging ballistic motion along filaments is frequently interrupted due to constricting intersection nodes or cycles of detachment and reattachment processes in the crowded cytoplasm. In order to investigate the efficiency of search strategies established by the cell’s specific spatial organization of the cytoskeleton we formulate a random velocity model with intermittent arrest states. With extensive computer simulations we analyze the dependence of the mean first passage times for narrow escape problems on the structural characteristics of the cytoskeleton, the motor properties and the fraction of time spent in each state. We find that an inhomogeneous architecture with a small width of the actin cortex constitutes an efficient intracellular search strategy.

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

Wu, Chung-Yeh; Wolf, William J.; Levartovsky, Yehonatan

We report the critical role in surface reactions and heterogeneous catalysis of metal atoms with low coordination numbers, such as found at atomic steps and surface defects, is firmly established. But despite the growing availability of tools that enable detailed in situ characterization, so far it has not been possible to document this role directly. Surface properties can be mapped with high spatial resolution, and catalytic conversion can be tracked with a clear chemical signature; however, the combination of the two, which would enable high-spatial-resolution detection of reactions on catalytic surfaces, has rarely been achieved. Single-molecule fluorescence spectroscopy has beenmore » used to image and characterize single turnover sites at catalytic surfaces, but is restricted to reactions that generate highly fluorescing product molecules. Herein the chemical conversion of N-heterocyclic carbene molecules attached to catalytic particles is mapped using synchrotron-radiation-based infrared nanospectroscopy with a spatial resolution of 25 nanometres, which enabled particle regions that differ in reactivity to be distinguished. Lastly, these observations demonstrate that, compared to the flat regions on top of the particles, the peripheries of the particles-which contain metal atoms with low coordination numbers-are more active in catalysing oxidation and reduction of chemically active groups in surface-anchored N-heterocyclic carbene molecules.« less

Students' Summaries of Mathematical Lectures: Comparing the Discourse of Students with the Discourse of Lectures

ERIC Educational Resources Information Center

Österholm, Magnus

2012-01-01

This study focuses on a distinction between process- and object-oriented discourses when characterising the discourse of university students' summaries of lectures and examining connections between students' discourse and the discourse of lectures. Results show that students' discourse in general tends to be process-oriented, by their use of…

Impedance-estimation methods, modeling methods, articles of manufacture, impedance-modeling devices, and estimated-impedance monitoring systems

DOEpatents

Richardson, John G [Idaho Falls, ID

2009-11-17

An impedance estimation method includes measuring three or more impedances of an object having a periphery using three or more probes coupled to the periphery. The three or more impedance measurements are made at a first frequency. Three or more additional impedance measurements of the object are made using the three or more probes. The three or more additional impedance measurements are made at a second frequency different from the first frequency. An impedance of the object at a point within the periphery is estimated based on the impedance measurements and the additional impedance measurements.

Base and collector resistances in heterojunction bipolar transistors

NASA Astrophysics Data System (ADS)

Anholt, R.; Bozada, C.; Desalvo, G.; Dettmer, R.; Ebel, J.; Gillespie, J.; Jenkins, T.; Havasy, C.; Ito, C.; Nakano, K.; Pettiford, C.; Quach, T.; Sewell, J.; Via, D.

1997-11-01

In heterojunction bipolar transistors (HBTs), the reverse base currents flow from the outer base periphery to the collector. The reverse base and collector resistances are therefore dominated by contact resistance, which is inversely proportional to the outer base and inner collector periphery lengths which are larger than the emitter lengths when the base and collector electrodes surround the emitter element. These resistances can be extracted from reverse Gummel (current vs Vbc with Vbc = 0) and from measurements of output resistances at zero collector voltage sweeps. We compare models with measurements where the base and collector peripheries decrease with increasing emitter diameters.

Challenges to the Israeli healthcare system: attracting medical students to primary care and to the periphery.

PubMed

Weissman, Charles; Zisk-Rony, Rachel Yaffa; Avidan, Alexander; Elchalal, Uriel; Tandeter, Howard

2018-05-29

The greatest challenges facing healthcare systems include ensuring a sufficient supply of primary care physicians and physicians willing to work in rural or peripheral areas. Especially challenging is enticing young physicians to practice primary care in rural/peripheral areas. Identifying medical students interested in primary care and in residencies in Israel's periphery should aid the healthcare leadership. It may be particularly important to do so during the clinical years, as this is the stage at which many future physicians begin to crystallize their specialty and location preferences. Questionnaires, distributed to 6 consecutive 5th-year classes of the Hebrew University - Hadassah School of Medicine, from 2010 to 2016, elicited information on criteria for choosing a career specialty, criteria for choosing a residency program and whether one-time monetary grants authorized in the 2011 physicians' union contract would attract students to residencies in the periphery. Completed questionnaires were returned by 511 of 740 (69%) students. Ninety-eight (19%) were interested in a primary care residency, 184 (36%) were unsure and 229 (45%) were not interested. Students interested in primary care were significantly less interested in specialties that perform procedures/surgeries and in joining a medical school faculty, while being more inclined towards specialties dealing with social problems, controllable lifestyles and working limited hours. The percentage of students interested in primary care was stable during the study period. Forty-eight of the students indicated interest in residencies in the country's periphery, and 42% of them were also interested in primary care residencies. Overall, only 3.7% of students were interested in both a primary care residency and a residency in the periphery. Thirty percent of the students indicated that the monetary incentives tempted them to consider a residency in the periphery. Fifty-three percent of these students reported that they did not yet know the geographic area where they wished to do their residency, as compared to only 22% among those not interested in incentives. This study provides the healthcare leadership with information on the characteristics of the students at a centrally-located medical school who tend to be more interested in primary care and in working in the periphery. Specifically, the study found that students interested in primary care desire a positive life/work balance, something that Israeli non-hospital primary care practice provides. Students considering residencies in the periphery were similarly inclined. Moreover, about a third of students had positive thoughts about monetary incentives for residencies in peripheral hospitals. These students should be identified early during their clinical experience so that attempts to recruit them to the periphery can commence before their specialty and location preferences have fully crystallized. Parallel studies should be performed at additional Israeli medical schools.

Spatial Structure of Evolutionary Models of Dialects in Contact

PubMed Central

Murawaki, Yugo

2015-01-01

Phylogenetic models, originally developed to demonstrate evolutionary biology, have been applied to a wide range of cultural data including natural language lexicons, manuscripts, folktales, material cultures, and religions. A fundamental question regarding the application of phylogenetic inference is whether trees are an appropriate approximation of cultural evolutionary history. Their validity in cultural applications has been scrutinized, particularly with respect to the lexicons of dialects in contact. Phylogenetic models organize evolutionary data into a series of branching events through time. However, branching events are typically not included in dialectological studies to interpret the distributions of lexical terms. Instead, dialectologists have offered spatial interpretations to represent lexical data. For example, new lexical items that emerge in a politico-cultural center are likely to spread to peripheries, but not vice versa. To explore the question of the tree model’s validity, we present a simple simulation model in which dialects form a spatial network and share lexical items through contact rather than through common ancestors. We input several network topologies to the model to generate synthetic data. We then analyze the synthesized data using conventional phylogenetic techniques. We found that a group of dialects can be considered tree-like even if it has not evolved in a temporally tree-like manner but has a temporally invariant, spatially tree-like structure. In addition, the simulation experiments appear to reproduce unnatural results observed in reconstructed trees for real data. These results motivate further investigation into the spatial structure of the evolutionary history of dialect lexicons as well as other cultural characteristics. PMID:26221958

Temporal dissociation between the focal and orientation components of spatial attention in central and peripheral vision.

PubMed

Albonico, Andrea; Malaspina, Manuela; Bricolo, Emanuela; Martelli, Marialuisa; Daini, Roberta

2016-11-01

Selective attention, i.e. the ability to concentrate one's limited processing resources on one aspect of the environment, is a multifaceted concept that includes different processes like spatial attention and its subcomponents of orienting and focusing. Several studies, indeed, have shown that visual tasks performance is positively influenced not only by attracting attention to the target location (orientation component), but also by the adjustment of the size of the attentional window according to task demands (focal component). Nevertheless, the relative weight of the two components in central and peripheral vision has never been studied. We conducted two experiments to explore whether different components of spatial attention have different effects in central and peripheral vision. In order to do so, participants underwent either a detection (Experiment 1) or a discrimination (Experiment 2) task where different types of cues elicited different components of spatial attention: a red dot, a small square and a big square (an optimal stimulus for the orientation component, an optimal and a sub-optimal stimulus for the focal component respectively). Response times and cue-size effects indicated a stronger effect of the small square or of the dot in different conditions, suggesting the existence of a dissociation in terms of mechanisms between the focal and the orientation components of spatial attention. Specifically, we found that the orientation component was stronger in periphery, while the focal component was noticeable only in central vision and characterized by an exogenous nature. Copyright © 2016 Elsevier B.V. All rights reserved.

Discourse on Discourse. Workshop Reports from the Macquarie Workshop on Discourse Analysis (Sydney, New South Wales, Australia, February 21-25, 1983). Occasional Papers Number 7.

ERIC Educational Resources Information Center

Hasan, Ruqaiya, Ed.

Four group summary papers from an Australian national workshop on discourse analysis discuss verbal and written discourse and the classroom. Papers reflect the four workshop discussion groups of casual conversation, classroom discourse, expository discourse, and literary narrative. They include: "On Casual Conversation" (M. A. K.…

Spatial differentiation of gene expression in Aspergillus niger colony grown for sugar beet pulp utilization

PubMed Central

Benoit, Isabelle; Zhou, Miaomiao; Vivas Duarte, Alexandra; Downes, Damien J.; Todd, Richard B.; Kloezen, Wendy; Post, Harm; Heck, Albert J. R.; Maarten Altelaar, A. F.; de Vries, Ronald P.

2015-01-01

Degradation of plant biomass to fermentable sugars is of critical importance for the use of plant materials for biofuels. Filamentous fungi are ubiquitous organisms and major plant biomass degraders. Single colonies of some fungal species can colonize massive areas as large as five soccer stadia. During growth, the mycelium encounters heterogeneous carbon sources. Here we assessed whether substrate heterogeneity is a major determinant of spatial gene expression in colonies of Aspergillus niger. We analyzed whole-genome gene expression in five concentric zones of 5-day-old colonies utilizing sugar beet pulp as a complex carbon source. Growth, protein production and secretion occurred throughout the colony. Genes involved in carbon catabolism were expressed uniformly from the centre to the periphery whereas genes encoding plant biomass degrading enzymes and nitrate utilization were expressed differentially across the colony. A combined adaptive response of carbon-catabolism and enzyme production to locally available monosaccharides was observed. Finally, our results demonstrate that A. niger employs different enzymatic tools to adapt its metabolism as it colonizes complex environments. PMID:26314379

Spatial differentiation of gene expression in Aspergillus niger colony grown for sugar beet pulp utilization.

PubMed

Benoit, Isabelle; Zhou, Miaomiao; Vivas Duarte, Alexandra; Downes, Damien J; Todd, Richard B; Kloezen, Wendy; Post, Harm; Heck, Albert J R; Maarten Altelaar, A F; de Vries, Ronald P

2015-08-28

Degradation of plant biomass to fermentable sugars is of critical importance for the use of plant materials for biofuels. Filamentous fungi are ubiquitous organisms and major plant biomass degraders. Single colonies of some fungal species can colonize massive areas as large as five soccer stadia. During growth, the mycelium encounters heterogeneous carbon sources. Here we assessed whether substrate heterogeneity is a major determinant of spatial gene expression in colonies of Aspergillus niger. We analyzed whole-genome gene expression in five concentric zones of 5-day-old colonies utilizing sugar beet pulp as a complex carbon source. Growth, protein production and secretion occurred throughout the colony. Genes involved in carbon catabolism were expressed uniformly from the centre to the periphery whereas genes encoding plant biomass degrading enzymes and nitrate utilization were expressed differentially across the colony. A combined adaptive response of carbon-catabolism and enzyme production to locally available monosaccharides was observed. Finally, our results demonstrate that A. niger employs different enzymatic tools to adapt its metabolism as it colonizes complex environments.

Auditory perception and the control of spatially coordinated action of deaf and hearing children.

PubMed

Savelsbergh, G J; Netelenbos, J B; Whiting, H T

1991-03-01

From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained.

The microtubule lattice and plus-end association of Drosophila Mini spindles is spatially regulated to fine-tune microtubule dynamics.

PubMed

Currie, Joshua D; Stewman, Shannon; Schimizzi, Gregory; Slep, Kevin C; Ma, Ao; Rogers, Stephen L

2011-11-01

Individual microtubules (MTs) exhibit dynamic instability, a behavior in which they cycle between phases of growth and shrinkage while the total amount of MT polymer remains constant. Dynamic instability is promoted by the conserved XMAP215/Dis1 family of microtubule-associated proteins (MAPs). In this study, we conducted an in vivo structure-function analysis of the Drosophila homologue Mini spindles (Msps). Msps exhibits EB1-dependent and spatially regulated MT localization, targeting to microtubule plus ends in the cell interior and decorating the lattice of growing and shrinking microtubules in the cell periphery. RNA interference rescue experiments revealed that the NH(2)-terminal four TOG domains of Msps function as paired units and were sufficient to promote microtubule dynamics and EB1 comet formation. We also identified TOG5 and novel inter-TOG linker motifs that are required for targeting Msps to the microtubule lattice. These novel microtubule contact sites are necessary for the interplay between the conserved TOG domains and inter-TOG MT binding that underlies the ability of Msps to promote MT dynamic instability.

Population changes in residential clusters in Japan.

PubMed

Sekiguchi, Takuya; Tamura, Kohei; Masuda, Naoki

2018-01-01

Population dynamics in urban and rural areas are different. Understanding factors that contribute to local population changes has various socioeconomic and political implications. In the present study, we use population census data in Japan to examine contributors to the population growth of residential clusters between years 2005 and 2010. The data set covers the entirety of Japan and has a high spatial resolution of 500 × 500 m2, enabling us to examine population dynamics in various parts of the country (urban and rural) using statistical analysis. We found that, in addition to the area, population density, and age, the shape of the cluster and the spatial distribution of inhabitants within the cluster are significantly related to the population growth rate of a residential cluster. Specifically, the population tends to grow if the cluster is "round" shaped (given the area) and the population is concentrated near the center rather than periphery of the cluster. Combination of the present results and analysis framework with other factors that have been omitted in the present study, such as migration, terrain, and transportation infrastructure, will be fruitful.

Visualizing Transmedia Networks: Links, Paths and Peripheries

ERIC Educational Resources Information Center

Ruppel, Marc Nathaniel

2012-01-01

'Visualizing Transmedia Networks: Links, Paths and Peripheries' examines the increasingly complex rhetorical intersections between narrative and media ("old" and "new") in the creation of transmedia fictions, loosely defined as multisensory and multimodal stories told extensively across a diverse media set. In order…

Density-Dependent Regulation of Brook Trout Population Dynamics along a Core-Periphery Distribution Gradient in a Central Appalachian Watershed

PubMed Central

Huntsman, Brock M.; Petty, J. Todd

2014-01-01

Spatial population models predict strong density-dependence and relatively stable population dynamics near the core of a species' distribution with increasing variance and importance of density-independent processes operating towards the population periphery. Using a 10-year data set and an information-theoretic approach, we tested a series of candidate models considering density-dependent and density-independent controls on brook trout population dynamics across a core-periphery distribution gradient within a central Appalachian watershed. We sampled seven sub-populations with study sites ranging in drainage area from 1.3–60 km2 and long-term average densities ranging from 0.335–0.006 trout/m. Modeled response variables included per capita population growth rate of young-of-the-year, adult, and total brook trout. We also quantified a stock-recruitment relationship for the headwater population and coefficients of variability in mean trout density for all sub-populations over time. Density-dependent regulation was prevalent throughout the study area regardless of stream size. However, density-independent temperature models carried substantial weight and likely reflect the effect of year-to-year variability in water temperature on trout dispersal between cold tributaries and warm main stems. Estimated adult carrying capacities decreased exponentially with increasing stream size from 0.24 trout/m in headwaters to 0.005 trout/m in the main stem. Finally, temporal variance in brook trout population size was lowest in the high-density headwater population, tended to peak in mid-sized streams and declined slightly in the largest streams with the lowest densities. Our results provide support for the hypothesis that local density-dependent processes have a strong control on brook trout dynamics across the entire distribution gradient. However, the mechanisms of regulation likely shift from competition for limited food and space in headwater streams to competition for thermal refugia in larger main stems. It also is likely that source-sink dynamics and dispersal from small headwater habitats may partially influence brook trout population dynamics in the main stem. PMID:24618602

Modeling a space-variant cortical representation for apparent motion.

PubMed

Wurbs, Jeremy; Mingolla, Ennio; Yazdanbakhsh, Arash

2013-08-06

Receptive field sizes of neurons in early primate visual areas increase with eccentricity, as does temporal processing speed. The fovea is evidently specialized for slow, fine movements while the periphery is suited for fast, coarse movements. In either the fovea or periphery discrete flashes can produce motion percepts. Grossberg and Rudd (1989) used traveling Gaussian activity profiles to model long-range apparent motion percepts. We propose a neural model constrained by physiological data to explain how signals from retinal ganglion cells to V1 affect the perception of motion as a function of eccentricity. Our model incorporates cortical magnification, receptive field overlap and scatter, and spatial and temporal response characteristics of retinal ganglion cells for cortical processing of motion. Consistent with the finding of Baker and Braddick (1985), in our model the maximum flash distance that is perceived as an apparent motion (Dmax) increases linearly as a function of eccentricity. Baker and Braddick (1985) made qualitative predictions about the functional significance of both stimulus and visual system parameters that constrain motion perception, such as an increase in the range of detectable motions as a function of eccentricity and the likely role of higher visual processes in determining Dmax. We generate corresponding quantitative predictions for those functional dependencies for individual aspects of motion processing. Simulation results indicate that the early visual pathway can explain the qualitative linear increase of Dmax data without reliance on extrastriate areas, but that those higher visual areas may serve as a modulatory influence on the exact Dmax increase.

Aerosol bolus dispersion in acinar airways—influence of gravity and airway asymmetry

PubMed Central

Ma, Baoshun

2012-01-01

The aerosol bolus technique can be used to estimate the degree of convective mixing in the lung; however, contributions of different lung compartments to measured dispersion cannot be differentiated unambiguously. To estimate dispersion in the distal lung, we studied the effect of gravity and airway asymmetry on the dispersion of 1 μm-diameter particle boluses in three-dimensional computational models of the lung periphery, ranging from a single alveolar sac to four-generation (g4) structures of bifurcating airways that deformed homogeneously during breathing. Boluses were introduced at the beginning of a 2-s inhalation, immediately followed by a 3-s exhalation. Dispersion was estimated by the half-width of the exhaled bolus. Dispersion was significantly affected by the spatial orientation of the models in normal gravity and was less in zero gravity than in normal gravity. Dispersion was strongly correlated with model volume in both normal and zero gravity. Predicted pulmonary dispersion based on a symmetric g4 acinar model was 391 ml and 238 ml under normal and zero gravity, respectively. These results accounted for a significant amount of dispersion measured experimentally. In zero gravity, predicted dispersion in a highly asymmetric model accounted for ∼20% of that obtained in a symmetric model with comparable volume and number of alveolated branches, whereas normal gravity dispersions were comparable in both models. These results suggest that gravitational sedimentation and not geometrical asymmetry is the dominant factor in aerosol dispersion in the lung periphery. PMID:22678957

Aerosol bolus dispersion in acinar airways--influence of gravity and airway asymmetry.

PubMed

Ma, Baoshun; Darquenne, Chantal

2012-08-01

The aerosol bolus technique can be used to estimate the degree of convective mixing in the lung; however, contributions of different lung compartments to measured dispersion cannot be differentiated unambiguously. To estimate dispersion in the distal lung, we studied the effect of gravity and airway asymmetry on the dispersion of 1 μm-diameter particle boluses in three-dimensional computational models of the lung periphery, ranging from a single alveolar sac to four-generation (g4) structures of bifurcating airways that deformed homogeneously during breathing. Boluses were introduced at the beginning of a 2-s inhalation, immediately followed by a 3-s exhalation. Dispersion was estimated by the half-width of the exhaled bolus. Dispersion was significantly affected by the spatial orientation of the models in normal gravity and was less in zero gravity than in normal gravity. Dispersion was strongly correlated with model volume in both normal and zero gravity. Predicted pulmonary dispersion based on a symmetric g4 acinar model was 391 ml and 238 ml under normal and zero gravity, respectively. These results accounted for a significant amount of dispersion measured experimentally. In zero gravity, predicted dispersion in a highly asymmetric model accounted for ∼20% of that obtained in a symmetric model with comparable volume and number of alveolated branches, whereas normal gravity dispersions were comparable in both models. These results suggest that gravitational sedimentation and not geometrical asymmetry is the dominant factor in aerosol dispersion in the lung periphery.

Seeing visual word forms: spatial summation, eccentricity and spatial configuration.

PubMed

Kao, Chien-Hui; Chen, Chien-Chung

2012-06-01

We investigated observers' performance in detecting and discriminating visual word forms as a function of target size and retinal eccentricity. The contrast threshold of visual words was measured with a spatial two-alternative forced-choice paradigm and a PSI adaptive method. The observers were to indicate which of two sides contained a stimulus in the detection task, and which contained a real character (as opposed to a pseudo- or non-character) in the discrimination task. When the target size was sufficiently small, the detection threshold of a character decreased as its size increased, with a slope of -1/2 on log-log coordinates, up to a critical size at all eccentricities and for all stimulus types. The discrimination threshold decreased with target size with a slope of -1 up to a critical size that was dependent on stimulus type and eccentricity. Beyond that size, the threshold decreased with a slope of -1/2 on log-log coordinates before leveling out. The data was well fit by a spatial summation model that contains local receptive fields (RFs) and a summation across these filters within an attention window. Our result implies that detection is mediated by local RFs smaller than any tested stimuli and thus detection performance is dominated by summation across receptive fields. On the other hand, discrimination is dominated by a summation within a local RF in the fovea but a cross RF summation in the periphery. Copyright © 2012 Elsevier Ltd. All rights reserved.

Visual spatial attention enhances the amplitude of positive and negative fMRI responses to visual stimulation in an eccentricity-dependent manner.

PubMed

Bressler, David W; Fortenbaugh, Francesca C; Robertson, Lynn C; Silver, Michael A

2013-06-07

Endogenous visual spatial attention improves perception and enhances neural responses to visual stimuli at attended locations. Although many aspects of visual processing differ significantly between central and peripheral vision, little is known regarding the neural substrates of the eccentricity dependence of spatial attention effects. We measured amplitudes of positive and negative fMRI responses to visual stimuli as a function of eccentricity in a large number of topographically-organized cortical areas. Responses to each stimulus were obtained when the stimulus was attended and when spatial attention was directed to a stimulus in the opposite visual hemifield. Attending to the stimulus increased both positive and negative response amplitudes in all cortical areas we studied: V1, V2, V3, hV4, VO1, LO1, LO2, V3A/B, IPS0, TO1, and TO2. However, the eccentricity dependence of these effects differed considerably across cortical areas. In early visual, ventral, and lateral occipital cortex, attentional enhancement of positive responses was greater for central compared to peripheral eccentricities. The opposite pattern was observed in dorsal stream areas IPS0 and putative MT homolog TO1, where attentional enhancement of positive responses was greater in the periphery. Both the magnitude and the eccentricity dependence of attentional modulation of negative fMRI responses closely mirrored that of positive responses across cortical areas. Copyright © 2013 Elsevier Ltd. All rights reserved.

Capitalist Discourse, Subjectivity and Lacanian Psychoanalysis

PubMed Central

Vanheule, Stijn

2016-01-01

This paper studies how subjectivity in capitalist culture can be characterized. Building on Lacan's later seminars XVI, XVII, XVIII, and XIX, the author first outlines Lacan's general discourse theory, which includes four characteristic discourses: the discourse of the master, the discourse of the university, the discourse of the hysteric and the discourse of the analyst. Next, the author explores the subjectivity and the mode of dealing with jouissance and semblance, which is entailed in a fifth type of discourse, the capitalist discourse, discussed by Lacan (1972). Indeed, like the other discourses that Lacan discerns, the discourse of the capitalist can be thought of as a mode of dealing with the sexual non-rapport. It is argued that in the case of neurosis the discourse of the capitalist functions as an attempt to ignore the sexual non-rapport and the dimension of the unconscious. Psychosis, by contrast, is marked by an a priori exclusion from discourse. In that case, consumerist ways of relating to the other might offer a semblance, and thus the possibility of inventing a mode of relating to the other. Two clinical vignettes are presented to illustrate this perspective: one concerning the neurotic structure and one concerning the psychotic structure. PMID:28018280

Complex structure of the carbon arc discharge for synthesis of nanotubes

DOE PAGES

Vekselman, V.; Feurer, M.; Huang, T.; ...

2017-06-06

Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C 2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc coremore » populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. Furthermore, this result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less

Adults with dyslexia demonstrate space-based and object-based covert attention deficits: shifting attention to the periphery and shifting attention between objects in the left visual field.

PubMed

Buchholz, Judy; Aimola Davies, Anne

2005-02-01

Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was invalidly cued were significantly higher for the group with dyslexia, while costs associated with shifts toward the fovea tended to be lower. Higher costs were also shown by the group with dyslexia for up-down shifts of attention in the periphery. A visual field processing difference was found, in that the group with dyslexia showed higher costs associated with shifting attention between objects in they LVF. These findings indicate that these adults with dyslexia have difficulty in both the space-based and the object-based components of covert visual attention, and more specifically to stimuli located in the periphery.

Conductivity tensor for anisotropic plasma in gyrokinetic theory

DOE PAGES

Porazik, Peter; Johnson, Jay R.

2017-05-18

Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C-2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc core populatedmore » with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. This result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less

Complex structure of the carbon arc discharge for synthesis of nanotubes

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

Vekselman, V.; Feurer, M.; Huang, T.

Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C 2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc coremore » populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. Furthermore, this result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less

Conductivity tensor for anisotropic plasma in gyrokinetic theory

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

Porazik, Peter; Johnson, Jay R.

Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C-2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc core populatedmore » with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. This result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less

The length of the dry season may be associated with leaf scleromorphism in cerrado plants.

PubMed

Souza, Marcelo C; Franco, Augusto C; Haridasan, Mundayatan; Rossatto, Davi R; de Araújo, Janaína F; Morellato, Leonor P C; Habermann, Gustavo

2015-09-01

Despite limitations of low fertility and high acidity of the soils, the cerrado flora is the richest amongst savannas. Many cerrado woody species show sclerophyllous leaves, which might be related to the availability of water and nutrients in the soil. To better understand the function and structure of cerrado vegetation within its own variations, we compared two cerrado communities: one in its core region in central Brazil (Brasília, DF) and the other on its southern periphery (Itirapina, SP). We contrasted the length of the dry season, soil fertility rates, leaf concentrations of N, P, K, Ca and Mg and the specific leaf area (SLA) between these communities. The dry season was shorter on the periphery, where the soil was more fertile although more acidic. Plants from the periphery showed higher SLA and higher leaf concentrations of N, P, Ca and Mg. We propose that the higher SLA of plants from the periphery is related to the shorter dry season, which allows better conditions for nutrient uptake.

An Overview of Discourse Analysis and Its Usefulness in TESOL.

ERIC Educational Resources Information Center

Milne, Geraldine Veronica

This paper provides an overview of discourse analysis from a linguistic point of view, discussing why it is relevant to Teaching English to Speakers of Other Languages (TESOL). It focuses on the following: discourse and discourse analysis; discourse analysis and TESOL; approaches to discourse analysis; systemic functional linguistics; theme and…

How far can Foucault take us?: an analysis of the changing discourses and limitations of the medical treatment of apoplexy and stroke.

PubMed

Daneski, Katharine; Higgs, Paul; Morgan, Myfanwy

2011-07-01

This article examines the conditions under which epistemological shifts in medicine have shaped the history of apoplexy and stroke. Our intention is to understand how stroke medicine as a distinct branch of bio-medicine has emerged in its current form. In doing so, we draw on aspects of the work of Michel Foucault as they relate to fabrication of biomedical discourses. The past 300 years of the transformation of the condition is examined using Michel Foucault's analysis of medical history as instances of the changing spatialization of disease. While the adoption of this approach helped explain how medical practice was shaped by changing interpretations of the causes of apoplexy and stroke over the past few centuries, we also found that there were certain limitations to such an approach. Overall, however, we hope to show that an examination of the history of stroke medicine through a Foucauldian influenced lens can provide a useful understanding of its current circumstances as well as throw light on gaps in Foucauldian approaches themselves.

Eye Movement Evidence for Hierarchy Effects on Memory Representation of Discourses.

PubMed

Wu, Yingying; Yang, Xiaohong; Yang, Yufang

2016-01-01

In this study, we applied the text-change paradigm to investigate whether and how discourse hierarchy affected the memory representation of a discourse. Three kinds of three-sentence discourses were constructed. In the hierarchy-high condition and the hierarchy-low condition, the three sentences of the discourses were hierarchically organized and the last sentence of each discourse was located at the high level and the low level of the discourse hierarchy, respectively. In the linear condition, the three sentences of the discourses were linearly organized. Critical words were always located at the last sentence of the discourses. These discourses were successively presented twice and the critical words were changed to semantically related words in the second presentation. The results showed that during the early processing stage, the critical words were read for longer times when they were changed in the hierarchy-high and the linear conditions, but not in the hierarchy-low condition. During the late processing stage, the changed-critical words were again found to induce longer reading times only when they were in the hierarchy-high condition. These results suggest that words in a discourse have better memory representation when they are located at the higher rather than at the lower level of the discourse hierarchy. Global discourse hierarchy is established as an important factor in constructing the mental representation of a discourse.

Eye Movement Evidence for Hierarchy Effects on Memory Representation of Discourses

PubMed Central

Wu, Yingying; Yang, Xiaohong; Yang, Yufang

2016-01-01

In this study, we applied the text-change paradigm to investigate whether and how discourse hierarchy affected the memory representation of a discourse. Three kinds of three-sentence discourses were constructed. In the hierarchy-high condition and the hierarchy-low condition, the three sentences of the discourses were hierarchically organized and the last sentence of each discourse was located at the high level and the low level of the discourse hierarchy, respectively. In the linear condition, the three sentences of the discourses were linearly organized. Critical words were always located at the last sentence of the discourses. These discourses were successively presented twice and the critical words were changed to semantically related words in the second presentation. The results showed that during the early processing stage, the critical words were read for longer times when they were changed in the hierarchy-high and the linear conditions, but not in the hierarchy-low condition. During the late processing stage, the changed-critical words were again found to induce longer reading times only when they were in the hierarchy-high condition. These results suggest that words in a discourse have better memory representation when they are located at the higher rather than at the lower level of the discourse hierarchy. Global discourse hierarchy is established as an important factor in constructing the mental representation of a discourse. PMID:26789002

Discourses of Education and Constitutions of Class: Public Discourses on Education in Swedish PBS Television

ERIC Educational Resources Information Center

Reimers, Eva

2014-01-01

Drawing on post-structural perspectives and analysis of television programs on education, the article investigates the public educational discourse in Sweden. It shows how a dominant neoliberal educational discourse is articulated together with a discourse of equal education, where the two discourses influence and subvert each other so that…

Task-Based Core-Periphery Organization of Human Brain Dynamics

PubMed Central

Bassett, Danielle S.; Wymbs, Nicholas F.; Rombach, M. Puck; Porter, Mason A.; Mucha, Peter J.; Grafton, Scott T.

2013-01-01

As a person learns a new skill, distinct synapses, brain regions, and circuits are engaged and change over time. In this paper, we develop methods to examine patterns of correlated activity across a large set of brain regions. Our goal is to identify properties that enable robust learning of a motor skill. We measure brain activity during motor sequencing and characterize network properties based on coherent activity between brain regions. Using recently developed algorithms to detect time-evolving communities, we find that the complex reconfiguration patterns of the brain's putative functional modules that control learning can be described parsimoniously by the combined presence of a relatively stiff temporal core that is composed primarily of sensorimotor and visual regions whose connectivity changes little in time and a flexible temporal periphery that is composed primarily of multimodal association regions whose connectivity changes frequently. The separation between temporal core and periphery changes over the course of training and, importantly, is a good predictor of individual differences in learning success. The core of dynamically stiff regions exhibits dense connectivity, which is consistent with notions of core-periphery organization established previously in social networks. Our results demonstrate that core-periphery organization provides an insightful way to understand how putative functional modules are linked. This, in turn, enables the prediction of fundamental human capacities, including the production of complex goal-directed behavior. PMID:24086116

R. S. Peters and the Periphery

ERIC Educational Resources Information Center

Haynes, Bruce

2013-01-01

Paul Hirst claimed that Richard Peters "revolutionised philosophy of education". This does not accord with my experience in the Antipodean periphery. My experience of the work of Wittgenstein, Austin and Kovesi before reading Peters and Dewey, Kuhn and Toulmin subsequently meant that Peters was a major but not revolutionary figure in my…

Neural correlates of three cognitive processes involved in theory of mind and discourse comprehension.

PubMed

Lin, Nan; Yang, Xiaohong; Li, Jing; Wang, Shaonan; Hua, Huimin; Ma, Yujun; Li, Xingshan

2018-04-01

Neuroimaging studies have found that theory of mind (ToM) and discourse comprehension involve similar brain regions. These brain regions may be associated with three cognitive components that are necessarily or frequently involved in ToM and discourse comprehension, including social concept representation and retrieval, domain-general semantic integration, and domain-specific integration of social semantic contents. Using fMRI, we investigated the neural correlates of these three cognitive components by exploring how discourse topic (social/nonsocial) and discourse processing period (ending/beginning) modulate brain activation in a discourse comprehension (and also ToM) task. Different sets of brain areas showed sensitivity to discourse topic, discourse processing period, and the interaction between them, respectively. The most novel finding was that the right temporoparietal junction and middle temporal gyrus showed sensitivity to discourse processing period only during social discourse comprehension, indicating that they selectively contribute to domain-specific semantic integration. Our finding indicates how different domains of semantic information are processed and integrated in the brain and provides new insights into the neural correlates of ToM and discourse comprehension.

Discourse as Medium of Knowledge: Transmission of Knowledge by Transmission of Discourse People Live

ERIC Educational Resources Information Center

Hassen, Rukya

2015-01-01

This is a study on discourse as medium of knowledge. Informal education is a system of transmission of knowledge by transmission of discourse people live by. In the humanities and social sciences, the term discourse describes a formal way of thinking that can be expressed through language. Discourses are seen to affect our views on all things; it…

An emerging discourse: toward epistemic diversity in nursing.

PubMed

Georges, Jane M

2003-01-01

Grounded in a postmodern feminist methodology, this article undertakes an initial analysis of a newly emerging discourse in contemporary nursing academia in the United States. Two currently prominent discourses in nursing, a dominant discourse informed by the processes and values of "science" in the Enlightenment sense and a concurrent marginalized discourse informed by postmodernism, are described as a context for the emerging discourse. A genealogy informed by the work of Foucault is presented as a basis for an analysis of the power effects resulting from the conflict between these 2 discourses. Finally, 3 recent texts in nursing are analyzed and common themes identified as indicative of a new intertextual discourse, termed "epistemic diversity," emerging from this discursive conflict.

The importance of causal connections in the comprehension of spontaneous spoken discourse.

PubMed

Cevasco, Jazmin; van den Broek, Paul

2008-11-01

In this study, we investigated the psychological processes in spontaneous discourse comprehension through a network theory of discourse representation. Existing models of narrative comprehension describe the importance of causality processing for forming a representation of a text, but usually in the context of deliberately composed texts rather than in spontaneous, unplanned discourse. Our aim was to determine whether spontaneous discourse components with many causal connections are represented more strongly than components with few connections--similar to the findings in text comprehension literature--and whether any such effects depend on the medium in which the spontaneous discourse is presented (oral vs. written). Participants either listened to or read a transcription of a section of a radio transmission. They then recalled the spontaneous discourse material and answered comprehension questions. Results indicate that the processing of causal connections plays an important role in the comprehension of spontaneous spoken discourse, and do not indicate that their effects on recall are weaker in the comprehension of oral discourse than in the comprehension of written discourse.

Concepts of Identity: East and West.

ERIC Educational Resources Information Center

Bailey, William

Rhetorical discourse and poetic discourse are distinct and must be studied accordingly. Rhetorical discourse treats the world pragmatically, whereas poetic discourse contains an aspect of decoration. Murray Krieger, as a representative of the New Criticism, claims that rhetorical discourse dualizes and alienates man from his world but that poetic…

Can Australia Avoid Repeating American and European Mistakes?

ERIC Educational Resources Information Center

Breen, Myles P.

In today's world, broad societal trends tend to originate in the center and migrate to the periphery. Europe and North America are in the center, and Australia is on the periphery. Of specific interest to communication scholars is the growth or ebbing of communication theories or techniques. One trend, the use of computers in communication…

Capitalism Reborn, Chaos and the Post-Socialist Freefall: A View from Europe's "New Periphery"

ERIC Educational Resources Information Center

Templer, Bill

2014-01-01

The present paper--from a vantage in Bulgaria, and focusing in significant part on this country as an iconic example of the "post-socialist freefall' and its dystopia on European capitalism's neocolonial "new periphery"--is a revised version of an earlier chapter in "Immiseration Capitalism and Education: Austerity, Resistance…

The Expanded Developmental Periphery: Framing the Institutional Role of University Continuing Education Units

ERIC Educational Resources Information Center

Fleming, Josephine

2013-01-01

This article argues that Burton Clark's notion of the expanded developmental periphery provides a useful conceptual framework for examining the differing relationships between continuing and professional education units and the institutional core of traditional research universities. The intent is to examine how Clark's notion offers a means to…

Bit by Bit: Innovating at the Periphery to Extend Harvard's Core

ERIC Educational Resources Information Center

Laserna, Catalina; Leitner, Henry

2008-01-01

Faculty instructional time is a critical resource at all universities, but particularly in a major research institution like Harvard. Operating on the periphery of the Faculty of Arts and Sciences, Harvard's division of Continuing Education is often at a disadvantage when attempting to recruit senior faculty. However, through its distance…

Arts Education and Cultural Democracy: The Competing Discourses

ERIC Educational Resources Information Center

Rasmussen, Bjørn

2017-01-01

Arts education are understood and implemented by ways of different discourses. Following critical discourse theory, discourses are part of power strategies and they predominantly fight for dominance. What this means is that certain discourses and accompanying practices of arts education may rule and others may be subordinated or neglected. A…

Troubling Discourses on Gender and Education

ERIC Educational Resources Information Center

Lahelma, Elina

2014-01-01

Background: In educational policies, two discourses on gender have existed since the 1980s. I call them the "gender equality discourse" and the "boy discourse". The gender equality discourse in education is based on international and national declarations and plans, and is focused predominantly on the position of girls and…

French Discourse Markers in Shaba Swahili Conversations.

ERIC Educational Resources Information Center

de Rooij, Vincent A.

2000-01-01

Examines data recorded in Shaba, a province in the Congo, and documents the marked preference to employ French discourse markers in Shaba Swahili discourse. Treats discourse markers as a special kind of contextualization cue that ties parts of a discourse to each other, creating cohesion and coherence. (Author/VWL)

Chemical dampening of Ly6C(hi) monocytes in the periphery produces anti-depressant effects in mice.

PubMed

Zheng, Xiao; Ma, Sijing; Kang, An; Wu, Mengqiu; Wang, Lin; Wang, Qiong; Wang, Guangji; Hao, Haiping

2016-01-19

The involvement of systemic immunity in depression pathogenesis promises a periphery-targeting paradigm in novel anti-depressant discovery. However, relatively little is known about druggable targets in the periphery for mental and behavioral control. Here we report that targeting Ly6C(hi) monocytes in blood can serve as a strategy for anti-depressant purpose. A natural compound, ginsenoside Rg1 (Rg1), was firstly validated as a periphery-restricted chemical probe. Rg1 selectively suppressed Ly6C(hi) monocytes recruitment to the inflamed mice brain. The proinflammatory potential of Ly6C(hi) monocytes to activate astrocytes was abrogated by Rg1, which led to a blunted feedback release of CCL2 to recruit the peripheral monocytes. In vitro study demonstrated that Rg1 pretreatment on activated THP-1 monocytes retarded their ability to trigger CCL2 secretion from co-cultured U251 MG astrocytes. CCL2-triggered p38/MAPK and PI3K/Akt activation were involved in the action of Rg1. Importantly, in mice models, we found that dampening Ly6C(hi) monocytes at the periphery ameliorated depression-like behavior induced by neuroinflammation or chronic social defeat stress. Together, our work unravels that blood Ly6C(hi) monocytes may serve as the target to enable remote intervention on the depressed brain, and identifies Rg1 as a lead compound for designing drugs targeting peripheral CCL2 signals.

The Perceptions of Elementary School Teachers Regarding Their Efforts to Help Students Utilize Student-to-Student Discourse in Science

NASA Astrophysics Data System (ADS)

Craddock, Jennifer Lovejoy

The purpose of this phenomenological study was to examine the perceptions of elementary teachers who teach science as opposed to science teacher specialists regarding their efforts to help students use student-to-student discourse for improving science learning. A growing body of research confirms the importance of a) student-to-student discourse for making meaning of science ideas and b) moving students' conceptual development towards a more scientific understanding of the natural world. Based on those foundations, the three research questions that guided this study examined the value elementary teachers place on student-to-student discourse, the various approaches teachers employ to promote the use of student-to-student discourse for learning science, and the factors and conditions that promote and inhibit the use of student-to-student discourse as an effective pedagogical strategy in elementary science. Data were gathered from 23 elementary teachers in a single district using an on-line survey and follow-up interviews with 8 teachers. All data were analyzed and evolving themes led to the following findings: (1) elementary teachers value student-to-student discourse in science, (2) teachers desire to increase time using student-to-student discourse, (3) teachers use a limited number of student-to-student discourse strategies to increase student learning in science, (4) teachers use student-to-student discourse as formative assessment to determine student learning in science, (5) professional development focusing on approaches to student-to-student discourse develops teachers' capacity for effective implementation, (6) teachers perceive school administrators' knowledge of and support for student-to-student discourse as beneficial, (7) time and scheduling constraints limit the use of student-to-student discourse in science. Implications of this study included the necessity of school districts to focus on student-to-student discourse in science, provide teacher and administrator professional development regarding student-to-student discourse instructional strategies, and promote collaboration across disciplines. This study suggests that future research be conducted regarding the role of administrators in fostering student-to-student discourse, the perspectives of secondary teachers implementing student-to-student discourse, the use of student-to-student discourse in other subjects, and leadership approaches to broadening the study across districts.

Discourse analysis: towards an understanding of its place in nursing.

PubMed

Crowe, Marie

2005-07-01

This paper describes how discourse analysis, and in particular critical discourse analysis, can be used in nursing research, and provides an example to illustrate the techniques involved. Discourse analysis has risen to prominence in the 1980s and 1990s in disciplines such as the social sciences, literary theory and cultural studies and is increasingly used in nursing. This paper investigates discourse analysis as a useful methodology for conducting nursing research. Effective clinical reasoning relies on employing several different kinds of knowledge and research that draw on different perspectives, methodologies and techniques to generate breadth of knowledge and depth of understanding of clinical practices and patients' experiences of those practices. The steps in a discourse analysis include: choosing the text, and identifying the explicit purpose of the text, the processes used for claiming authority connections to other discourses, construction of major concepts, processes of naming and categorizing, construction of subject positions, construction of reality and social relations and implications for the practice of nursing. The limitations of discourse analysis, its relationship to other qualitative approaches and questions for evaluating the rigour of research using discourse analysis are also explored. The example of discourse analysis shows how a text influences the practice of nursing by shaping knowledge, values and beliefs. Discourse analysis can make a contribution to the development of nursing knowledge by providing a research strategy to examine dominant discourses that influence nursing practice.

Research into Practice: The Influence of Discourse Studies on Language Descriptions and Task Design in Published ELT Materials

ERIC Educational Resources Information Center

Gilmore, Alex

2015-01-01

Discourse studies is a vast, multidisciplinary, and rapidly expanding area of research, embracing a range of approaches including discourse analysis, corpus analysis, conversation analysis, interactional sociolinguistics, critical discourse analysis, genre analysis and multimodal discourse analysis. Each approach offers its own unique perspective…

Discourse Markers in EFL Setting: Perceptions of Turkish EFL Teachers

ERIC Educational Resources Information Center

Asik, Asuman

2015-01-01

Discourse markers are seen as one of the fundamental units in spoken discourse due to their frequent and multifunctional use by native speakers of English. Discourse markers also have significance in foreign language instruction. In this respect, this study explored the perceptions of Turkish EFL teachers towards the use of discourse markers in…

Accessibility Marking: Discourse Functions, Discourse Profiles, and Processing Cues

ERIC Educational Resources Information Center

Ariel, Mira

2004-01-01

When accounting for the usage of some linguistic form, one can refer to its discourse profile, all concomitant features frequently co-occurring with that form in discourse, or abstract a more general claim about its discourse function, referring only to the necessary and sufficient conditions for the proper occurrence of the form. This article…

Constructing Israeli and Palestinian Identity: A Multimodal Critical Discourse Analysis of World History Textbooks and Teacher Discourse

ERIC Educational Resources Information Center

Osborn, Daniel

2017-01-01

This research critically evaluates the depiction of Israelis and Palestinians in World History textbooks and World History teachers' instructional discourse. Employing a Multimodal Critical Discourse Analysis methodology, this study offers a comparison between written narratives and spoken discourse in order to analyze the portrayals found in…

Discourse Analysis and Language Learning [Summary of a Symposium].

ERIC Educational Resources Information Center

Hatch, Evelyn

1981-01-01

A symposium on discourse analysis and language learning is summarized. Discourse analysis can be divided into six fields of research: syntax, the amount of syntactic organization required for different types of discourse, large speech events, intra-sentential cohesion in text, speech acts, and unequal power discourse. Research on speech events and…

Discourse as Social Interaction. Discourse Studies: A Multidisciplinary Introduction. Volume 2.

ERIC Educational Resources Information Center

van Dijk, Teun A., Ed.

The collection of essays on discourse as a form of social interaction includes: "Discourse as Interaction in Society" (Teun A. van Dijk); "Discourse Pragmatics" (Shoshana Blum-Kulka); "Conversation Analysis: An Approach to the Study of Social Action as Sense Making Practices" (Anita Pomerantz, B. J. Fehr); "Institutional Dialogue" (Paul Drew,…

Modeling discourse management compared to other classroom management styles in university physics

NASA Astrophysics Data System (ADS)

Desbien, Dwain Michael

2002-01-01

A classroom management technique called modeling discourse management was developed to enhance the modeling theory of physics. Modeling discourse management is a student-centered management that focuses on the epistemology of science. Modeling discourse is social constructivist in nature and was designed to encourage students to present classroom material to each other. In modeling discourse management, the instructor's primary role is of questioner rather than provider of knowledge. Literature is presented that helps validate the components of modeling discourse. Modeling discourse management was compared to other classroom management styles using multiple measures. Both regular and honors university physics classes were investigated. This style of management was found to enhance student understanding of forces, problem-solving skills, and student views of science compared to traditional classroom management styles for both honors and regular students. Compared to other reformed physics classrooms, modeling discourse classes performed as well or better on student understanding of forces. Outside evaluators viewed modeling discourse classes to be reformed, and it was determined that modeling discourse could be effectively disseminated.

Topic Structure Affects Semantic Integration: Evidence from Event-Related Potentials

PubMed Central

Yang, Xiaohong; Chen, Xuhai; Chen, Shuang; Xu, Xiaoying; Yang, Yufang

2013-01-01

This study investigated whether semantic integration in discourse context could be influenced by topic structure using event-related brain potentials. Participants read discourses in which the last sentence contained a critical word that was either congruent or incongruent with the topic established in the first sentence. The intervening sentences between the first and the last sentence of the discourse either maintained or shifted the original topic. Results showed that incongruent words in topic-maintained discourses elicited an N400 effect that was broadly distributed over the scalp while those in topic-shifted discourses elicited an N400 effect that was lateralized to the right hemisphere and localized over central and posterior areas. Moreover, a late positivity effect was only elicited by incongruent words in topic-shifted discourses, but not in topic-maintained discourses. This suggests an important role for discourse structure in semantic integration, such that compared with topic-maintained discourses, the complexity of discourse structure in topic-shifted condition reduces the initial stage of semantic integration and enhances the later stage in which a mental representation is updated. PMID:24348994

Topic structure affects semantic integration: evidence from event-related potentials.

PubMed

Yang, Xiaohong; Chen, Xuhai; Chen, Shuang; Xu, Xiaoying; Yang, Yufang

2013-01-01

This study investigated whether semantic integration in discourse context could be influenced by topic structure using event-related brain potentials. Participants read discourses in which the last sentence contained a critical word that was either congruent or incongruent with the topic established in the first sentence. The intervening sentences between the first and the last sentence of the discourse either maintained or shifted the original topic. Results showed that incongruent words in topic-maintained discourses elicited an N400 effect that was broadly distributed over the scalp while those in topic-shifted discourses elicited an N400 effect that was lateralized to the right hemisphere and localized over central and posterior areas. Moreover, a late positivity effect was only elicited by incongruent words in topic-shifted discourses, but not in topic-maintained discourses. This suggests an important role for discourse structure in semantic integration, such that compared with topic-maintained discourses, the complexity of discourse structure in topic-shifted condition reduces the initial stage of semantic integration and enhances the later stage in which a mental representation is updated.

Exploring the Role of `Gendered' Discourse Styles in Online Science Discussions

NASA Astrophysics Data System (ADS)

Sullivan, Florence R.; Kapur, Manu; Madden, Sandra; Shipe, Stefanie

2015-02-01

In this study, we examined whether gendered discourse styles were evidenced in online, synchronous, physics collaborative learning group discussions, and the extent to which such discourse patterns were related to the uptake of ideas within the group. We defined two discourse styles: the oppositional/direct style, theorized to be the socialized discourse pattern typically used by males, and the aligned/indirect style, theorized to be the socialized discourse pattern typically used by females. Our analysis indicates the presence of both styles in these chats and the styles were generally utilized along theorized, gendered lines. However, we also observed male use of the stereotypically 'feminine' discourse style and female use of the stereotypically 'masculine' discourse style. Moreover, we found no main effect for discourse style on the uptake of ideas. The findings indicate that, contrary to prior research in both face-to-face science classroom settings and online physics settings, ideas were taken up at relatively similar rates regardless of the gendered discourse style employed. Design implications of this study are discussed and suggestions for future research are made.

What makes up good consultations? A qualitative study of GPs' discourses.

PubMed

Van Roy, Kaatje; Vanheule, Stijn; Deveugele, Myriam

2013-05-16

In medical literature, several principles that define 'good consultations' have been outlined. These principles tend to be prescriptive in nature, overlooking the complexity of general practitioners (GPs)' perspectives of everyday practice. Focusing on perspectives might be particularly relevant, since they may affect decisions and actions. Therefore, the present study adopts a bottom-up approach, analyzing GPs' narratives about 'good' and 'bad' consultations. We aimed at describing the range of discourses GPs use in relating on their practice. Semi-structured interviews were conducted with 19 Belgian GPs. By means of a qualitative analysis, the authors mapped patterns in the interview narratives and described the range of different discourses. Four discourses were identified: a biomedically-centered discourse, a communication-focused discourse, a problem-solving discourse and a satisfaction-oriented discourse. Each discourse was further specified in terms of predominant themes, problems the GPs prefer to deal with and inherent difficulties. Although most participants used elements from all four discourses, the majority of the GPs relied on an individual set of predominant discourses and focused on a limited number of themes. This study clearly indicates that there is no uniform way in which GPs perceive clinical practice. Each of the participants used a subtle mix of different criteria to define good and bad medical consultations. Some discourse elements appear to be rooted in medical literature, whereas others are of a more personal nature. By focusing on the limitations of each discourse, this study can shed new light on some of the difficulties GPs encounter in their daily practice: being confronted with specific problems might be an effect of adhering to a specific discourse. The typification of different discourses on consultations may function as a framework to help GPs reflect on how they perceive their practice, and help them manage some of the challenges met in daily practice.

Climates of risk: a field analysis of global climate change in US media discourse, 1997-2004.

PubMed

Sonnett, John

2010-11-01

How are industry and environmentalist discourses of climate risk related to dominant scientific and political discourses? This study operationalizes Bourdieu's concept of symbolic capital in order to map dimensions of risk description and prescription onto a journalistic field of industry, environmentalist, scientific, and political media. Results show that conventional definitions of risk mirror an opposition between scientific and political discourses. Prescriptions for action on risk are partly autonomous from definitions however. Environmentalist and scientific media feature more proactive discourse, and industry and political media feature more reactive discourse. Implications for future research on climate risk and relational studies of media discourse are discussed.

Discursive constructions of professional identity in policy and regulatory discourse.

PubMed

Fealy, Gerard; Hegarty, Josephine-Mary; McNamara, Martin; Casey, Mary; O'Leary, Denise; Kennedy, Catriona; O'Reilly, Pauline; O'Connell, Rhona; Brady, Anne-Marie; Nicholson, Emma

2018-05-23

To examine and describe disciplinary discourses conducted through professional policy and regulatory documents in nursing and midwifery in Ireland. A key tenet of discourse theory is that group identities are constructed in public discourses and these discursively-constructed identities become social realities. Professional identities can be extracted from both the explicit and latent content of discourse. Studies of nursing's disciplinary discourse have drawn attention to a dominant discourse that confers nursing with particular identities, which privilege the relational and affective aspects of nursing and in the process, marginalise scientific knowledge and the technical and body work of nursing. We used critical discourse analysis to analyse a purposive sample of nursing and midwifery regulatory and policy documents. We applied a four-part, sequential approach to analysing the selected texts. This involved identifying key words, phrases and statements that indicated dominant discourses that, in turn, revealed latent beliefs and assumptions. The focus of our analysis was on how the discourses construct professional identities. Our analysis indicated recurring narratives that appeared to confer nurses and midwives with three dominant identities: 'the knowledgeable practitioner', the 'interpersonal practitioner' and the 'accountable practitioner'. The discourse also carried assumptions about the form and content of disciplinary knowledge. Academic study of identity construction in discourse is important to disciplinary development by raising nurses' and midwives' consciousness, alerting them to the ways that their own discourse can shape their identities, influence public and political opinion and, in the process, shape public policy on their professions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Sensitivity of an eight-element phased array coil in 3 Tesla MR imaging: a basic analysis.

PubMed

Hiratsuka, Yoshiyasu; Miki, Hitoshi; Kikuchi, Keiichi; Kiriyama, Ikuko; Mochizuki, Teruhito; Takahashi, Shizue; Sadamoto, Kazuhiko

2007-01-01

To evaluate the performance advantages of an 8-element phased array head coil (8 ch coil) over a conventional quadrature-type birdcage head coil (QD coil) with regard to the signal-to-noise ratio (SNR) and image uniformity in 3 Tesla magnetic resonance (MR) imaging. We scanned a phantom filled with silicon oil using an 8 ch coil and a QD coil in a 3T MR imaging system and compared the SNR and image uniformity obtained from T(1)-weighted spin echo (SE) images and T(2)-weighted fast SE images between the 2 coils. We also visually evaluated images from 4 healthy volunteers. The SNR with the 8 ch coil was approximately twice that with the QD coil in the region of interest (ROI), which was set as 75% of the area in the center of the phantom images. With regard to the spatial variation of sensitivity, the SNR with the 8 ch coil was lower at the center of the images than at the periphery, whereas the SNR with the QD coil exhibited an inverse pattern. At the center of the images with the 8 ch coil, the SNR was somewhat lower, and that distribution was relatively flat compared to that in the periphery. Image uniformity varied less with the 8 ch coil than with the QD coil on both imaging sequences. The 8 ch phased array coil was useful for obtaining high quality 3T images because of its higher SNR and improved image uniformity than those obtained with conventional quadrature-type birdcage head coil.

Professional development, practice, and teacher discourse communities: How an urban high school science teacher negotiated inquiry practice

NASA Astrophysics Data System (ADS)

Deneroff, Victoria Matzenauer

This is an ethnographic case study of one urban high school science teacher who was attempting to use inquiry-based teaching in her practice. Rather than focusing on pedagogy, the study examines the social networks and communities of practice in which Marie Gonzalez participated. I make the argument that science teaching is a Discourse (Gee, 1990), and that teaching inquiry science means constructing an identity as a participant in what I call the Discourse of Inquiry. I also use discourse analysis to tease out a Discourse of Traditional Science Teaching. I conclude that the Traditional and Inquiry Discourses mediate a teacher's ideas of what it means to teach, and that, while Inquiry teachers are "bilingual", that is, able to participate in both Discourses, Traditional teachers are deaf to the Discourse of Inquiry. Moreover, in my study there is convincing evidence that administrators charged with evaluation were also unfamiliar with the Discourse of Inquiry and were therefore unable to provide support for Marie's inquiry practice. In light of these findings, it is not at all surprising that Marie found it quite difficult to use inquiry-based pedagogy. In order for teachers to adopt discourse-based reforms such as inquiry, the Discourse must be available to teachers in their workplaces.

Serpentine metal gasket

DOEpatents

Rothgeb, Timothy Moore [Norfolk, VA; Reece, Charles Edwin [Yorktown, VA

2009-06-02

A metallic seal or gasket for use in the joining of cryogenic fluid conduits, the seal or gasket having a generally planar and serpentine periphery defining a central aperture. According to a preferred embodiment, the periphery has at least two opposing elongated serpentine sides and two opposing arcuate ends joining the opposing elongated serpentine sides and is of a hexagonal cross-section.

On the Relationality of Centers, Peripheries and Interactional Regimes: Translanguaging in a Community Interpreting Event

ERIC Educational Resources Information Center

Baynham, Mike; Hanušová, Jolana

2017-01-01

In this paper we discuss a multilingual interactional event that involves both interpreting and literacy work, part of a large scale study on translanguaging in superdiverse urban settings. In the first part of the interaction, the center/periphery dynamic is played out in what might be called "contested translanguaging" between Standard…

Disrupting Adult and Community Education: Teaching, Learning, and Working in the Periphery

ERIC Educational Resources Information Center

Mizzi, Robert C., Ed.; Rocco, Tonette S., Ed.; Shore, Sue, Ed.

2016-01-01

This groundbreaking book critiques the boundaries of where adult education takes place through a candid examination of teaching, learning, and working practices in the social periphery. Lives in this context are diverse and made through complex practices that take place in the shadows of formal systems: on streetscapes and farms, in vehicles and…

Young Women in a Male Periphery: Experiences from the Scandinavian North.

ERIC Educational Resources Information Center

Dahlstrom, Margareta

1996-01-01

Suggests that young women migrate from rural to urban areas in northern Scandinavia because the rural "periphery" is dominated by male economic and leisure activities. A study in northern Norway indicates that more young women than young men valued higher education and highly qualified careers, both of which were more attainable in urban…

Evolution of digital angiography systems.

PubMed

Brigida, Raffaela; Misciasci, Teresa; Martarelli, Fabiola; Gangitano, Guido; Ottaviani, Pierfrancesco; Rollo, Massimo; Marano, Pasquale

2003-01-01

The innovations introduced by digital subtraction angiography in digital radiography are briefly illustrated with the description of its components and functioning. The pros and cons of digital subtraction angiography are analyzed in light of present and future imaging technologies. In particular, among advantages there are: automatic exposure, digital image subtraction, digital post-processing, high number of images per second, possible changes in density and contrast. Among disadvantages there are: small round field of view, geometric distortion at the image periphery, high sensitivity to patient movements, not very high spatial resolution. At present, flat panel detectors represent the most suitable substitutes for digital subtraction angiography, with the introduction of novel solutions for those artifacts which for years have hindered its diagnostic validity. The concept of temporal artifact, reset light and possible future evolutions of this technology that may afford both diagnostic and protectionist advantages, are analyzed.

Resistive anode image converter

NASA Technical Reports Server (NTRS)

Lampton, M. L.; Paresce, F. (Inventor)

1976-01-01

The invention of an apparatus for imaging soft X-ray and ultraviolet electromagnetic radiation and charged particles was described. The apparatus includes a pair of microchannel electron multiplier plates connected in a cascaded chevron configuration which intercepts an incident beam of radiation or charged particles. Incident photons or charged particles strike the front surface of the chevron configuration causing emission of electrons. The electrons are accelerated by a voltage gradient and strike the inner side walls of the individual channels, causing emission of secondary electrons. Accelerated and multiplied secondary electrons impinge upon a resistive anode after they transverse the chevron configuration. A pulse position circuit converts the magnitude or transit time of the currents flowing from the point of impact of the electrons on the resistive anode to four contact electrodes mounted on their periphery of the resistive anode into the spatial coordinates of electron impact.

Border Forces and Friction Control Epithelial Closure Dynamics

PubMed Central

Cochet-Escartin, Olivier; Ranft, Jonas; Silberzan, Pascal; Marcq, Philippe

2014-01-01

We study the closure dynamics of a large number of well-controlled circular apertures within an epithelial monolayer, where the collective cell migration responsible for epithelization is triggered by the removal of a spatial constraint rather than by scratching. Based on experimental observations, we propose a physical model that takes into account border forces, friction with the substrate, and tissue rheology. Border protrusive activity drives epithelization despite the presence of a contractile actomyosin cable at the periphery of the wound. The closure dynamics is quantified by an epithelization coefficient, defined as the ratio of protrusive stress to tissue-substrate friction, that allows classification of different phenotypes. The same analysis demonstrates a distinct signature for human cells bearing the oncogenic RasV12 mutation, demonstrating the potential of the approach to quantitatively characterize metastatic transformations. PMID:24411238

Gender, sexuality and the discursive representation of access and equity in health services literature: implications for LGBT communities

PubMed Central

2011-01-01

Background This article considers how health services access and equity documents represent the problem of access to health services and what the effects of that representation might be for lesbian, gay, bisexual and transgender (LGBT) communities. We conducted a critical discourse analysis on selected access and equity documents using a gender-based diversity framework as determined by two objectives: 1) to identify dominant and counter discourses in health services access and equity literature; and 2) to develop understanding of how particular discourses impact the inclusion, or not, of LGBT communities in health services access and equity frameworks.The analysis was conducted in response to public health and clinical research that has documented barriers to health services access for LGBT communities including institutionalized heterosexism, biphobia, and transphobia, invisibility and lack of health provider knowledge and comfort. The analysis was also conducted as the first step of exploring LGBT access issues in home care services for LGBT populations in Ontario, Canada. Methods A critical discourse analysis of selected health services access and equity documents, using a gender-based diversity framework, was conducted to offer insight into dominant and counter discourses underlying health services access and equity initiatives. Results A continuum of five discourses that characterize the health services access and equity literature were identified including two dominant discourses: 1) multicultural discourse, and 2) diversity discourse; and three counter discourses: 3) social determinants of health (SDOH) discourse; 4) anti-oppression (AOP) discourse; and 5) citizen/social rights discourse. Conclusions The analysis offers a continuum of dominant and counter discourses on health services access and equity as determined from a gender-based diversity perspective. The continuum of discourses offers a framework to identify and redress organizational assumptions about, and ideological commitments to, sexual and gender diversity and health services access and equity. Thus, the continuum of discourses may serve as an important element of a health care organization's access and equity framework for the evaluation of access to good quality care for diverse LGBT populations. More specfically, the analysis offers four important points of consideration in relation to the development of a health services access and equity framework. PMID:21957894

Gender, sexuality and the discursive representation of access and equity in health services literature: implications for LGBT communities.

PubMed

Daley, Andrea E; Macdonnell, Judith A

2011-09-29

This article considers how health services access and equity documents represent the problem of access to health services and what the effects of that representation might be for lesbian, gay, bisexual and transgender (LGBT) communities. We conducted a critical discourse analysis on selected access and equity documents using a gender-based diversity framework as determined by two objectives: 1) to identify dominant and counter discourses in health services access and equity literature; and 2) to develop understanding of how particular discourses impact the inclusion, or not, of LGBT communities in health services access and equity frameworks.The analysis was conducted in response to public health and clinical research that has documented barriers to health services access for LGBT communities including institutionalized heterosexism, biphobia, and transphobia, invisibility and lack of health provider knowledge and comfort. The analysis was also conducted as the first step of exploring LGBT access issues in home care services for LGBT populations in Ontario, Canada. A critical discourse analysis of selected health services access and equity documents, using a gender-based diversity framework, was conducted to offer insight into dominant and counter discourses underlying health services access and equity initiatives. A continuum of five discourses that characterize the health services access and equity literature were identified including two dominant discourses: 1) multicultural discourse, and 2) diversity discourse; and three counter discourses: 3) social determinants of health (SDOH) discourse; 4) anti-oppression (AOP) discourse; and 5) citizen/social rights discourse. The analysis offers a continuum of dominant and counter discourses on health services access and equity as determined from a gender-based diversity perspective. The continuum of discourses offers a framework to identify and redress organizational assumptions about, and ideological commitments to, sexual and gender diversity and health services access and equity. Thus, the continuum of discourses may serve as an important element of a health care organization's access and equity framework for the evaluation of access to good quality care for diverse LGBT populations. More specfically, the analysis offers four important points of consideration in relation to the development of a health services access and equity framework.

FUEL ELEMENT FOR NEUTRONIC REACTORS

DOEpatents

Evans, T.C.; Beasley, E.G.

1961-01-17

A fuel element for neutronic reactors, particularly the gas-cooled type of reactor, is described. The element comprises a fuel-bearing plate rolled to form a cylinder having a spiral passageway passing from its periphery to its center. In operation a coolant is admitted to the passageway at the periphery of the element, is passed through the spiral passageway, and emerges into a central channel defined by the inner turn of the rolled plate. The advantage of the element is that the fully heated coolant (i.e., coolant emerging into the central channel) is separated and thus insulated from the periphery of the element, which may be in contact with a low-temperature moderator, by the intermediate turns of the spiral fuel element.

Attention, Intention and the Structure of Discourse. Technical Report No. 380.

ERIC Educational Resources Information Center

Grosz, B. J.; Sidner, C. L.

Developing and integrating two lines of research, one focusing on discourse and the other on intention recognition in discourse, this paper presents the basic elements of a computational theory of discourse. The paper argues that by specifying the basic units a discourse comprises and the ways in which they can relate, an account of discourse…

A quantitative test of population genetics using spatiogenetic patterns in bacterial colonies.

PubMed

Korolev, Kirill S; Xavier, João B; Nelson, David R; Foster, Kevin R

2011-10-01

It is widely accepted that population-genetics theory is the cornerstone of evolutionary analyses. Empirical tests of the theory, however, are challenging because of the complex relationships between space, dispersal, and evolution. Critically, we lack quantitative validation of the spatial models of population genetics. Here we combine analytics, on- and off-lattice simulations, and experiments with bacteria to perform quantitative tests of the theory. We study two bacterial species, the gut microbe Escherichia coli and the opportunistic pathogen Pseudomonas aeruginosa, and show that spatiogenetic patterns in colony biofilms of both species are accurately described by an extension of the one-dimensional stepping-stone model. We use one empirical measure, genetic diversity at the colony periphery, to parameterize our models and show that we can then accurately predict another key variable: the degree of short-range cell migration along an edge. Moreover, the model allows us to estimate other key parameters, including effective population size (density) at the expansion frontier. While our experimental system is a simplification of natural microbial community, we argue that it constitutes proof of principle that the spatial models of population genetics can quantitatively capture organismal evolution.

The energy divide: Integrating energy transitions, regional inequalities and poverty trends in the European Union

PubMed Central

Bouzarovski, Stefan; Tirado Herrero, Sergio

2016-01-01

Energy poverty can be understood as the inability of a household to secure a socially and materially necessitated level of energy services in the home. While the condition is widespread across Europe, its spatial and social distribution is highly uneven. In this paper, the existence of a geographical energy poverty divide in the European Union (EU) provides a starting point for conceptualizing and exploring the relationship between energy transitions – commonly described as wide-ranging processes of socio-technical change – and existing patterns of regional economic inequality. We have undertaken a comprehensive analysis of spatial and temporal trends in the national-scale patterns of energy poverty, as well as gas and electricity prices. The results of our work indicate that the classic economic development distinction between the core and periphery also holds true in the case of energy poverty, as the incidence of this phenomenon is significantly higher in Southern and Eastern European EU Member States. The paper thus aims to provide the building blocks for a novel theoretical integration of questions of path-dependency, uneven development and material deprivation in existing interpretations of energy transitions. PMID:28690374

Action Enhances Acoustic Cues for 3-D Target Localization by Echolocating Bats

PubMed Central

Wohlgemuth, Melville J.

2016-01-01

Under natural conditions, animals encounter a barrage of sensory information from which they must select and interpret biologically relevant signals. Active sensing can facilitate this process by engaging motor systems in the sampling of sensory information. The echolocating bat serves as an excellent model to investigate the coupling between action and sensing because it adaptively controls both the acoustic signals used to probe the environment and movements to receive echoes at the auditory periphery. We report here that the echolocating bat controls the features of its sonar vocalizations in tandem with the positioning of the outer ears to maximize acoustic cues for target detection and localization. The bat’s adaptive control of sonar vocalizations and ear positioning occurs on a millisecond timescale to capture spatial information from arriving echoes, as well as on a longer timescale to track target movement. Our results demonstrate that purposeful control over sonar sound production and reception can serve to improve acoustic cues for localization tasks. This finding also highlights the general importance of movement to sensory processing across animal species. Finally, our discoveries point to important parallels between spatial perception by echolocation and vision. PMID:27608186

Weak conservation of structural features in the interfaces of homologous transient protein–protein complexes

PubMed Central

Sudha, Govindarajan; Singh, Prashant; Swapna, Lakshmipuram S; Srinivasan, Narayanaswamy

2015-01-01

Residue types at the interface of protein–protein complexes (PPCs) are known to be reasonably well conserved. However, we show, using a dataset of known 3-D structures of homologous transient PPCs, that the 3-D location of interfacial residues and their interaction patterns are only moderately and poorly conserved, respectively. Another surprising observation is that a residue at the interface that is conserved is not necessarily in the interface in the homolog. Such differences in homologous complexes are manifested by substitution of the residues that are spatially proximal to the conserved residue and structural differences at the interfaces as well as differences in spatial orientations of the interacting proteins. Conservation of interface location and the interaction pattern at the core of the interfaces is higher than at the periphery of the interface patch. Extents of variability of various structural features reported here for homologous transient PPCs are higher than the variation in homologous permanent homomers. Our findings suggest that straightforward extrapolation of interfacial nature and inter-residue interaction patterns from template to target could lead to serious errors in the modeled complex structure. Understanding the evolution of interfaces provides insights to improve comparative modeling of PPC structures. PMID:26311309

Transverse tripolar stimulation of peripheral nerve: a modelling study of spatial selectivity.

PubMed

Deurloo, K E; Holsheimer, J; Boom, H B

1998-01-01

Various anode-cathode configurations in a nerve cuff are modelled to predict their spatial selectivity characteristics for functional nerve stimulation. A 3D volume conductor model of a monofascicular nerve is used for the computation of stimulation-induced field potentials, whereas a cable model of myelinated nerve fibre is used for the calculation of the excitation thresholds of fibres. As well as the usual configurations (monopole, bipole, longitudinal tripole, 'steering' anode), a transverse tripolar configuration (central cathode) is examined. It is found that the transverse tripole is the only configuration giving convex recruitment contours and therefore maximises activation selectivity for a small (cylindrical) bundle of fibres in the periphery of a monofascicular nerve trunk. As the electrode configuration is changed to achieve greater selectivity, the threshold current increases. Therefore threshold currents for fibre excitation with a transverse tripole are relatively high. Inverse recruitment is less extreme than for the other configurations. The influences of several geometrical parameters and model conductivities of the transverse tripole on selectivity and threshold current are analysed. In chronic implantation, when electrodes are encapsulated by a layer of fibrous tissue, threshold currents are low, whereas the shape of the recruitment contours in transverse tripolar stimulation does not change.

Are visual peripheries forever young?

PubMed

Burnat, Kalina

2015-01-01

The paper presents a concept of lifelong plasticity of peripheral vision. Central vision processing is accepted as critical and irreplaceable for normal perception in humans. While peripheral processing chiefly carries information about motion stimuli features and redirects foveal attention to new objects, it can also take over functions typical for central vision. Here I review the data showing the plasticity of peripheral vision found in functional, developmental, and comparative studies. Even though it is well established that afferent projections from central and peripheral retinal regions are not established simultaneously during early postnatal life, central vision is commonly used as a general model of development of the visual system. Based on clinical studies and visually deprived animal models, I describe how central and peripheral visual field representations separately rely on early visual experience. Peripheral visual processing (motion) is more affected by binocular visual deprivation than central visual processing (spatial resolution). In addition, our own experimental findings show the possible recruitment of coarse peripheral vision for fine spatial analysis. Accordingly, I hypothesize that the balance between central and peripheral visual processing, established in the course of development, is susceptible to plastic adaptations during the entire life span, with peripheral vision capable of taking over central processing.

Regulation and spatial organization of PCNA in Trypanosoma brucei

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

Kaufmann, Doris; Gassen, Alwine; Maiser, Andreas

2012-03-23

Highlights: Black-Right-Pointing-Pointer Characterization of the proliferating cell nuclear antigen in Trypanosoma brucei (TbPCNA). Black-Right-Pointing-Pointer TbPCNA is a suitable marker to detect replication in T. brucei. Black-Right-Pointing-Pointer TbPCNA distribution and regulation is different compared to closely related parasites T. cruzi and Leishmania donovani. -- Abstract: As in most eukaryotic cells, replication is regulated by a conserved group of proteins in the early-diverged parasite Trypanosoma brucei. Only a few components of the replication machinery have been described in this parasite and regulation, sub-nuclear localization and timing of replication are not well understood. We characterized the proliferating cell nuclear antigen in T. bruceimore » (TbPCNA) to establish a spatial and temporal marker for replication. Interestingly, PCNA distribution and regulation is different compared to the closely related parasites Trypanosoma cruzi and Leishmania donovani. TbPCNA foci are clearly detectable during S phase of the cell cycle but in contrast to T. cruzi they are not preferentially located at the nuclear periphery. Furthermore, PCNA seems to be degraded when cells enter G2 phase in T. brucei suggesting different modes of replication regulation or functions of PCNA in these closely related eukaryotes.« less

Fullerene-Based Symmetry in Hibiscus rosa-sinensis Pollen

PubMed Central

Andrade, Kleber; Guerra, Sara; Debut, Alexis

2014-01-01

The fullerene molecule belongs to the so-called super materials. The compound is interesting due to its spherical configuration where atoms occupy positions forming a mechanically stable structure. We first demonstrate that pollen of Hibiscus rosa-sinensis has a strong symmetry regarding the distribution of its spines over the spherical grain. These spines form spherical hexagons and pentagons. The distance between atoms in fullerene is explained applying principles of flat, spherical, and spatial geometry, based on Euclid’s “Elements” book, as well as logic algorithms. Measurements of the pollen grain take into account that the true spine lengths, and consequently the real distances between them, are measured to the periphery of each grain. Algorithms are developed to recover the spatial effects lost in 2D photos. There is a clear correspondence between the position of atoms in the fullerene molecule and the position of spines in the pollen grain. In the fullerene the separation gives the idea of equal length bonds which implies perfectly distributed electron clouds while in the pollen grain we suggest that the spines being equally spaced carry an electrical charge originating in forces involved in the pollination process. PMID:25003375

The Discourse of Social Justice within European Education Policy Developments: The Example of Key Competences and Indicator Development towards Assuring the Continuation of Democracy

ERIC Educational Resources Information Center

Hoskins, Bryony

2008-01-01

Neo-liberal discourse is described by many critical education researchers as almost the only discourse within European education policy making. However, although this discourse clearly exists and is powerful, the author identifies an alternative discourse within European Union policy making which incorporates narratives of social justice,…

Discourses in stroke rehabilitation as they present themselves in current physiotherapy and occupational therapy.

PubMed

Kristensen, Hanne Kaae; Præstegaard, Jeanette; Ytterberg, Charlotte

2017-02-01

Aim This study aims to discuss current perceptions of rehabilitation and how present rehabilitation practice is affected by dominating discourses in Danish society by exploring discourses expressed in official publications and the constructed journal notes of occupational and physiotherapists' practice of stroke rehabilitation. Method The frame of reference is Fairclough's critical discourse analysis. The analysis comprises seven official documents relevant to stroke rehabilitation provided in Danish health services in 2012-2013. Also, notes written by occupational therapists and physiotherapists in medical records of 10 patients with a stroke diagnosis admitted to hospital in 2012. The documents included were read thoroughly. The texts were analyzed deductively, focusing on discursive practice on articulated understandings of rehabilitation, health practice approaches, and social practice. Results The dominating discourses seem to be Western neoliberalism organizational, medical and ethical discourses. The macro level of discourses consisted of political documents addressing rehabilitation nationally. The meso level mainly concerned medical discourses within stroke rehabilitation whereas the micro level represented local medical and ethical discourses. Conclusion The neoliberal discourse supports the medical discourse with strong emphasis on evidence-based interventions. In contrast to ethical discourses, documentation of rehabilitation practice marked more attention being paid to facilitating the patient's independence than to enabling the regaining of meaningful activities and participation. Implications for Rehabilitation Individualized rehabilitation must be organized with flexibility as it is a complex process Critical reflectiveness among health professionals is needed to provide individualized rehabilitation of high quality A broader range of stake holders, including patient organizations, are in demand within health policy making The discourses that construct rehabilitation policy and practices are sometimes in conflict, which may impact on, and impede, the rehabilitation for the individual patient.

[Application of locomotor activity test to evaluate functional injury after global cerebral ischemia in C57BL/6 mice].

PubMed

Zhang, Li-quan; Xu, Jia-ni; Wang, Zhen-zhen; Zeng, Li-jun; Ye, Yi-lu; Zhang, Wei-ping; Wei, Er-qing; Zhang, Qi

2014-05-01

To evaluate the application of locomotor activity test in functional injury after global cerebral ischemia (GCI) in C57BL/6 mice. GCI was induced by bilateral carotid arteries occlusion for 30 min in C57BL/6 mice. Mice were divided into sham group, GCI group and minocycline group. Saline or minocycline (45 mg/kg) was i.p. injected once daily for 6 d after ischemia. At Day 6 after ischemia, locomotor activity was recorded for 1 h in open field test. Total distance, central distance, central distance ratio, periphery distance, periphery distance ratio, central time and periphery time were used to evaluate the behavior characteristics of locomotor activity in C57BL/6 mice after ischemia. The survival neuron density was detected by Nissl staining in hippocampus, cortex and striatum. Compared with sham group, total distance, central distance and central time increased and periphery time decreased in C57BL/6 mice after GCI (Ps<0.05). However, minocycline significantly reduced the central distance and central time and increased the periphery time (Ps<0.05). Neurons were damaged in hippocampus, cortex and striatum after GCI, which manifested by decreased neurons and the most serious damage in hippocampal CA1 region. Minocycline significantly improved the neuron appearance and increased the neuron number in hippocampus and striatum (P<0.001 or P<0.05). Locomotor activity in open field test can objectively evaluate the behavior injury after GCI in mice. Central distance and central time can be used as indexes of quantitative assessment.

The iris signal: blue periphery, tan collaret and freckles pattern - strong indicators for epidermal skin cancer in South-Eastern Europe.

PubMed

Grigore, M; Furtunescu, F; Minca, D; Costache, M; Garbe, C; Simionescu, O

2018-03-10

Eye and skin share the embryological origin. Both are established risk factors in epidermal skin cancer. There are few reports using iris colour classification scales, most of them analyse colour in general or are too complex to use in daily practice. To investigate which iris colour pattern is associated with epidermal skin cancer in a S-E European Caucasian population. A case-control study was conducted on 480 patients: 229 skin cancers patients and 251 controls (dermatological patients free of skin cancers) admitted in two medical clinics of Dermatology in Bucharest, between October 2011 and May 2014. High-resolution iris photographs were taken for each patient. Three parameters of the iris were analysed individually and in association patterns for each patient: periphery, collaret and freckles. The most frequent iris colour pattern associated with epidermal skin cancer was blue periphery with light brown collaret and freckles present. In terms of individual parameters, the strongest indicators for skin cancer patients were blue periphery and blue collaret. The results of this study sustain the hypothesis that blue periphery with light brown collaret and freckles iris pattern is a reliable phenotypic marker for epidermal skin cancer. The results of this study differ from previous reports in which skin cancer risk was associated with a homogeneous blue iris. We account these differences in the characteristics of the recruited patients (S-E European, skin type II and III). The assessment of iris colour patterns is an easy and inexpensive detection tool in skin cancer risk assessment. © 2018 European Academy of Dermatology and Venereology.

Real and Non-Real Time Interaction: Unraveling Multiple Threads of Discourse.

ERIC Educational Resources Information Center

Black, Steven D.; And Others

1983-01-01

Compares discourse in several different media and finds that strict sequentiality is not a universal feature of discourse. Concludes that discourse in nonreal time media, such as electronic message systems, has multiple threads. (FL)

PhD Crisis Discourse: A Critical Approach to the Framing of the Problem and Some Australian "Solutions"

ERIC Educational Resources Information Center

Cuthbert, Denise; Molla, Tebeje

2015-01-01

A feature of HE reform discourse is the tendency to construct the rationale for reform in terms of averting calamity and risk. We refer to this risk talk as "crisis discourse." This study examines the formulation of PhD crisis discourse internationally and in Australia. We find that a key feature of PhD crisis discourse is that…

Deaf Culture and Competing Discourses in a Residential School for the Deaf: "Can Do" versus "Can't Do"

ERIC Educational Resources Information Center

O'Brien, Catherine A.; Placier, Peggy

2015-01-01

From an ethnographic case study of a state-funded residential school for the Deaf, the authors employed Critical Discourse Analysis to identify competing discourses in the talk of educators. These discourses are embedded in the historical oppression and labeling of deaf people as disabled and the development of Deaf culture as a counter-discourse.…

Whoever Doesn't HOP Must Be Superior: The Russian Left-Periphery and the Emergence of Superiority

ERIC Educational Resources Information Center

Scott, Tatiana V.

2012-01-01

This dissertation maps the left-periphery of the Russian language, presenting a new geometry of Russian main and subordinate clauses in order to account for a number of phenomena: single and multiple wh-constructions, sluicing constructions, and coordinate multiple wh-constructions (CMW), as well as to predict various occurring word-orders.…

Diffraction smoothing aperture for an optical beam

DOEpatents

Judd, O'Dean P.; Suydam, Bergen R.

1976-01-01

The disclosure is directed to an aperture for an optical beam having an irregular periphery or having perturbations imposed upon the periphery to decrease the diffraction effect caused by the beam passing through the aperture. Such apertures are particularly useful with high power solid state laser systems in that they minimize the problem of self-focusing which frequently destroys expensive components in such systems.

What's the Place of Queer Theory in Studies of Gender, Sexuality, and Education on the Periphery?

ERIC Educational Resources Information Center

Rasmussen, Mary Lou

2016-01-01

This article is an exploration of the problem of theorizing gender and sexuality of people who Raewyn Connell might describe as coming from the global periphery, but whose lives and futures are also enmeshed in the politics, policies, and pedagogies of the metropole. Elizabeth Povinelli has done extensive research on Indigenous people in the…

Responses to Targets in the Visual Periphery in Deaf and Normal-Hearing Adults

ERIC Educational Resources Information Center

Rothpletz, Ann M.; Ashmead, Daniel H.; Tharpe, Anne Marie

2003-01-01

The purpose of this study was to compare the response times of deaf and normal-hearing individuals to the onset of target events in the visual periphery in distracting and nondistracting conditions. Visual reaction times to peripheral targets placed at 3 eccentricities to the left and right of a center fixation point were measured in prelingually…

Sutureless Corneal Transplantation Apparatus And Method

DOEpatents

Rowsey, J. James

1996-12-17

An eye with a cornea repaired without sutures comprising a donor material in the shape of a partial sphere having a generally central extent, the central extent being of the size and shape of the central portion of a cornea of an eye, the central extent having a periphery of a fixed diameter with an exterior surface in a convex configuration and an interior surface in a concave configuration and with an essentially common thickness throughout, the central extent having a plurality of corneal flaps extending radially from the periphery of the central extent, the flaps having exterior surfaces as a continuation of the exterior surface of the central extent; and a recipient eye in the shape of a partial sphere having a circular aperture in the cornea at its central portion, the central aperture being of a size and shape essentially that of the periphery of the central extent of the donor material, the aperture being of a common thickness at the periphery of the aperture, the central portion having pockets and with the central extent of the donor material located within the aperture of the recipient eye and with the flaps of the central extent being imbricated into the pockets of the recipient eye.

[The rule of lymphatic formation in rabbit VX2 supraglottic carcinoma model with lymph node metastasis].

PubMed

Zhang, Pin; Ji, Wenyue; Zhang, Xiangbo

2012-02-01

Establishment of transplanted model of VX2 supraglottic carcinoma in rabbits and investigation the rule of lymphatic vessels formation. After establishment of VX2 tumor-bearing rabbits, the carcinoma tissues were transplanted into the operculum laryngis submucosa in sixty New-Zealand white rabbits to establish transplanted tumor model. Vascular endothelial growth factor-3 (VEGFR-3) label staining was performed to observe lymphatic vessels. Number density, volume density of lymphatics periphery region of carcinoma, normal region and centre region were measured using computer image analysis system. There was no lymphatic vessels in carcinomatous centre region,but the lymphatic vessels number density, volume density in periphery region was much more than normal region. Their cavities were dilated. The discrepancy had statistical significance (P<0.01). The rule of lymphatic formation in rabbit VX2 supraglottic carcinoma model mimesis rule of lymphatic formation anthropo- supraglottic carcinoma. Lymphatic multiplication and dilation at periphery region of carcinoma is associated with lymph node metastasis. Evaluation of it at periphery region of carcinoma may be useful in predicting lymph node metastasis in patients with supraglottic carcinoma. This conclusion provides theoretical basis for utility of the anti-tumor medicines which inhibit lymphatic formation in animal model.

Shallow Processing and Underspecification

ERIC Educational Resources Information Center

Sanford, Anthony J.; Graesser, Arthur C.

2006-01-01

Discourse comprehension theories frequently assume that discourse comprehension involves a complete analysis of lexical, syntactic, semantic, and discourse levels of processing. However, discourse psychologists have documented some conditions when a partial processing and underspecification of the resulting representations occurs. The articles in…

Disclosing discourses: biomedical and hospitality discourses in patient education materials.

PubMed

Öresland, Stina; Friberg, Febe; Määttä, Sylvia; Öhlen, Joakim

2015-09-01

Patient education materials have the potential to strengthen the health literacy of patients. Previous studies indicate that readability and suitability may be improved. The aim of this study was to explore and analyze discourses inherent in patient education materials since analysis of discourses could illuminate values and norms inherent in them. Clinics in Sweden that provided colorectal cancer surgery allowed access to written information and 'welcome letters' sent to patients. The material was analysed by means of discourse analysis, embedded in Derrida's approach of deconstruction. The analysis revealed a biomedical discourse and a hospitality discourse. In the biomedical discourse, the subject position of the personnel was interpreted as the messenger of medical information while that of the patients as the carrier of diagnoses and recipients of biomedical information. In the hospitality discourse, the subject position of the personnel was interpreted as hosts who invite and welcome the patients as guests. The study highlights the need to eliminate paternalism and fosters a critical reflective stance among professionals regarding power and paternalism inherent in health care communication. © 2015 John Wiley & Sons Ltd.

Tunable-focus liquid lens controlled using a servo motor

NASA Astrophysics Data System (ADS)

Ren, Hongwen; Fox, David; Anderson, P. Andrew; Wu, Benjamin; Wu, Shin-Tson

2006-09-01

We demonstrated a liquid lens whose focal length can be controlled by an actuator. The lens cell is composed of elastic membrane, planar glass plate, a periphery sealing ring, and a liquid with a fixed volume in the lens chamber. Part of the periphery sealing ring is excavated to form a hollow chamber which functions as a reservoir. This hollowed periphery is surrounded by an exterior rubber membrane. The shaft of an actuator is used to deform the elastic rubber. Squeezing the liquid contained in the reservoir into the lens chamber. Excess liquid in the lens chamber will push the lens membrane to outward, resulting in a lens shape change. Due to the compact structure and easy operation, this liquid lens has potential applications in zoom lenses, auto beam steering, and eyeglasses.

Politics of change: the discourses that inform organizational change and their capacity to silence.

PubMed

McMillan, Kim

2016-09-01

Changes in healthcare organizations are inevitable and occurring at unprecedented rates. Such changes greatly impact nurses and their work, yet these experiences are rarely explored. Organizational change discourses remain grounded in perspectives that explore and explain systems, often not the people within them. Change processes in healthcare organizations informed by such organizational discourses validate only certain perspectives and forms of knowledge. This fosters exclusionary practices, limiting the capacity of certain individuals or groups of individuals to effectively contribute to change discourses and processes. The reliance on mainstream organizational discourses in healthcare organizations has left little room for the exploration of diverse perspectives on the subject of organizational change, particularly those of nurses. Michel Foucault's work challenges dominant discourse and suggest that strong reliance's on specific discourses effectively disqualify certain forms of knowledge. Foucault's writings on disqualified knowledge and parrhesia (truth telling and frank speech) facilitate the critical exploration of discourses that inform change in healthcare organizations and nurses capacities to contribute to organizational discourses. This paper explores the capacity of nurses to speak their truths within rapidly and continuously changing healthcare organizations when such changes are often driven by discourses not derived from nursing knowledge or experience. © 2016 John Wiley & Sons Ltd.

Expanding Discourse Repertoires with Hybridity

ERIC Educational Resources Information Center

Kelly, Gregory J.

2012-01-01

In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally…

Discourse Tracing as Qualitative Practice

ERIC Educational Resources Information Center

LeGreco, Marianne; Tracy, Sarah J.

2009-01-01

This article introduces a qualitative research method called "discourse tracing". Discourse tracing draws from contributions made by ethnographers, discourse critics, case study scholars, and process tracers. The approach offers new insights and an attendant language about how we engage in research designed specifically for the…

Debris exhaust system

DOEpatents

McBride, Donald D.; Bua, Dominic; Domankevitz, Yacov; Nishioka, Norman

1998-01-01

A debris removal system removes debris from a work site by flowing fluid away from the work site toward the periphery of a structure. The fluid flow can be kept constant around the periphery so that debris is removed evenly. The structure can have a reduced cross section between the fluid inlet and the work site so that the resulting increased fluid velocity works to prevent debris from escaping.

US Study Abroad from the Periphery to the Center of the Global Curriculum in the Information Age

ERIC Educational Resources Information Center

Mukherjee, Mousumi

2012-01-01

The Higher Education Act of 1965 for the first time gave discretionary authority to campuses to use federal financial aid in support of students studying abroad. Thereafter, US study abroad has thus evolved from the periphery to the center of the global curriculum. In 2005 the Lincoln Commission report proposed an ambitious goal of sending one…

Overcoming Multidimensional Marginality: The Significance of Higher Education for Traditionally Reared Single Mothers Living in the Outer Periphery

ERIC Educational Resources Information Center

Greenberg, Zeev; Shenaar-Golan, Vered

2017-01-01

The current study gives voice to a group of remarkable returning college students whose lives are defined by multidimensional marginality. These students are single mothers who grew up in traditional families in the outer periphery of Northern Israel, where they still lived at the time of this study. Drawing on the women's life stories gathered…

Debris exhaust system

DOEpatents

McBride, D.D.; Bua, D.; Domankevitz, Y.; Nishioka, N.

1998-06-23

A debris removal system removes debris from a work site by flowing fluid away from the work site toward the periphery of a structure. The fluid flow can be kept constant around the periphery so that debris is removed evenly. The structure can have a reduced cross section between the fluid inlet and the work site so that the resulting increased fluid velocity works to prevent debris from escaping. 9 figs.

Synthesis and characterization of novel thermoplastic elastomers employing polyhedral oligomeric silsesquioxane physical crosslinks

NASA Astrophysics Data System (ADS)

Seurer, Bradley

Polyhedral oligomeric silsesquioxanes (POSS) are molecularly precise isotropic particles with average diameters of 1-2 nm. A typical T 8 POSS nanoparticle has an inorganic Si8O12 core surrounded by eight aliphatic or aromatic groups attached to the silicon vertices of the polyhedron promoting solubility in conventional solvents. Previously, efficient synthetic methods have been developed whereby one of the aliphatic groups on the periphery is substituted by a functional group capable of undergoing either homo- or copolymerization. In the current investigations, preparative methods for the chemical incorporation of POSS macromonomers in a series elastomers have been developed. Analysis of the copolymers using WAXD reveals that pendant POSS groups off the polymer backbones aggregate, and can crystallize as nanocrystals. From both line-broadening of the diffraction maxima, and also the oriented diffraction in a drawn material, the individual POSS sub-units are crystallizing as anisotropically shaped crystallites. The formation of POSS particle aggregation is strongly dependent on the nature of the polymeric matrix and the POSS peripheral group. X-ray studies show aggregation of POSS in ethylene-propylene elastomers occurred only with a phenyl periphery, whereas POSS particles with isobutyl and ethyl peripheries disperse within the polymer matrix. By altering the polymer matrix to one containing chain repulsive fluorine units, aggregation is observed with both the phenyl and isobutyl peripheries. Altering the polymer chain to poly(dimethylcyclooctadiene), POSS aggregates with isobutyl, ethyl, cyclopentyl, and phenyl peripheries. The formation of POSS nanocrystals increases the mechanical properties of these novel thermoplastic elastomers, including an increase in the tensile storage modulus and formation of a rubbery plateau region. Tensile tests of these elastomers show an increase in elastic modulus with increasing POSS loading. The elongation at break was as high as 720%. Cyclic tensile test show some hysteresis of the elastomers. However, the curves show Mullins effect behavior, commonly seen in elastomers. Elastomers with POSS dispersion, however, show poor mechanical properties. These results demonstrate the novel material property gains by the incorporation and aggregation of POSS in thermoplastic elastomers, as well as the influence of the POSS periphery.

Discourse Analysis in Ethnographic Research.

ERIC Educational Resources Information Center

Poole, Deborah

1990-01-01

Reviews the contribution of ethnographic research to discourse analysis, focusing on discourse practices as a reflection of cultural context; educational applications and the discontinuity issue; literacy as a focus of discourse-oriented ethnographic research; and implications for applied linguistics. A 9-citation annotated and a 50-citation…

The Complexity of Chinese Pedagogic Discourse

ERIC Educational Resources Information Center

Cheng, Liang; Xu, Nan

2011-01-01

This is one of the commentaries on Wu's "Interpretation, autonomy, and transformation: Chinese pedagogic discourse in a cross-cultural perspective" ("JCS", 43(5), 569-590). It highlights the paper's demystification of Western pedagogic discourse and recovery of the meaning of Chinese traditional pedagogic discourse as a…

Discourse changes in early Alzheimer disease, mild cognitive impairment, and normal aging.

PubMed

Chapman, Sandra Bond; Zientz, Jennifer; Weiner, Myron; Rosenberg, Roger; Frawley, William; Burns, Mary Hope

2002-01-01

The purpose of this study was to determine the sensitivity of discourse gist measures to the early cognitive-linguistic changes in Alzheimer disease (AD) and in the preclinical stages. Differences in discourse abilities were examined in 25 cognitively normal adults, 24 adults with mild probable AD, and 20 adults with mild cognitive impairment (MCI) at gist and detail levels of discourse processing. The authors found that gist and detail levels of discourse processing were significantly impaired in persons with AD and MCI as compared with normal control subjects. Gist-level discourse processing abilities showed minimal overlap between cognitively normal control subjects and those with mild AD. Moreover, the majority of the persons with MCI performed in the range of AD on gist measures. These findings indicate that discourse gist measures hold promise as a diagnostic complement to enhance early detection of AD. Further studies are needed to determine how early the discourse gist deficits arise in AD.

Discourse analysis and the impact of the philosophy of Enlightenment in nursing research.

PubMed

Beedholm, Kirsten; Lomborg, Kirsten; Frederiksen, Kirsten

2014-06-01

Discourse analysis has been introduced into nursing research as an approach which has the potential to offer new perspectives and to pose new questions to taken-for-granted assumptions. However, critique has arisen that when applied to nursing studies, the epistemological foundation of the discourse analysis is often overlooked. It is furthermore claimed that the methodological inspiration does not lead to any new insights and that these studies can hardly be differentiated from more traditional studies. This study supports this critique, arguing that the challenges of implementing discourse analysis in nursing research reflect a dominant pattern of thought in the discourse of the nursing profession that have held sway throughout the last century. We argue that this pattern of thought stems from the Western philosophy of consciousness and the conception of the sovereign subject. By applying a discourse analytical perspective to the discourse of the nursing profession itself, this study elucidates the challenges of applying discourse analysis in nursing research. © 2013 John Wiley & Sons Ltd.

An Eye Tracking Study on the Perception and Comprehension of Unimodal and Bimodal Linguistic Inputs by Deaf Adolescents

PubMed Central

Mastrantuono, Eliana; Saldaña, David; Rodríguez-Ortiz, Isabel R.

2017-01-01

An eye tracking experiment explored the gaze behavior of deaf individuals when perceiving language in spoken and sign language only, and in sign-supported speech (SSS). Participants were deaf (n = 25) and hearing (n = 25) Spanish adolescents. Deaf students were prelingually profoundly deaf individuals with cochlear implants (CIs) used by age 5 or earlier, or prelingually profoundly deaf native signers with deaf parents. The effectiveness of SSS has rarely been tested within the same group of children for discourse-level comprehension. Here, video-recorded texts, including spatial descriptions, were alternately transmitted in spoken language, sign language and SSS. The capacity of these communicative systems to equalize comprehension in deaf participants with that of spoken language in hearing participants was tested. Within-group analyses of deaf participants tested if the bimodal linguistic input of SSS favored discourse comprehension compared to unimodal languages. Deaf participants with CIs achieved equal comprehension to hearing controls in all communicative systems while deaf native signers with no CIs achieved equal comprehension to hearing participants if tested in their native sign language. Comprehension of SSS was not increased compared to spoken language, even when spatial information was communicated. Eye movements of deaf and hearing participants were tracked and data of dwell times spent looking at the face or body area of the sign model were analyzed. Within-group analyses focused on differences between native and non-native signers. Dwell times of hearing participants were equally distributed across upper and lower areas of the face while deaf participants mainly looked at the mouth area; this could enable information to be obtained from mouthings in sign language and from lip-reading in SSS and spoken language. Few fixations were directed toward the signs, although these were more frequent when spatial language was transmitted. Both native and non-native signers looked mainly at the face when perceiving sign language, although non-native signers looked significantly more at the body than native signers. This distribution of gaze fixations suggested that deaf individuals – particularly native signers – mainly perceived signs through peripheral vision. PMID:28680416

An Eye Tracking Study on the Perception and Comprehension of Unimodal and Bimodal Linguistic Inputs by Deaf Adolescents.

PubMed

Mastrantuono, Eliana; Saldaña, David; Rodríguez-Ortiz, Isabel R

2017-01-01

An eye tracking experiment explored the gaze behavior of deaf individuals when perceiving language in spoken and sign language only, and in sign-supported speech (SSS). Participants were deaf ( n = 25) and hearing ( n = 25) Spanish adolescents. Deaf students were prelingually profoundly deaf individuals with cochlear implants (CIs) used by age 5 or earlier, or prelingually profoundly deaf native signers with deaf parents. The effectiveness of SSS has rarely been tested within the same group of children for discourse-level comprehension. Here, video-recorded texts, including spatial descriptions, were alternately transmitted in spoken language, sign language and SSS. The capacity of these communicative systems to equalize comprehension in deaf participants with that of spoken language in hearing participants was tested. Within-group analyses of deaf participants tested if the bimodal linguistic input of SSS favored discourse comprehension compared to unimodal languages. Deaf participants with CIs achieved equal comprehension to hearing controls in all communicative systems while deaf native signers with no CIs achieved equal comprehension to hearing participants if tested in their native sign language. Comprehension of SSS was not increased compared to spoken language, even when spatial information was communicated. Eye movements of deaf and hearing participants were tracked and data of dwell times spent looking at the face or body area of the sign model were analyzed. Within-group analyses focused on differences between native and non-native signers. Dwell times of hearing participants were equally distributed across upper and lower areas of the face while deaf participants mainly looked at the mouth area; this could enable information to be obtained from mouthings in sign language and from lip-reading in SSS and spoken language. Few fixations were directed toward the signs, although these were more frequent when spatial language was transmitted. Both native and non-native signers looked mainly at the face when perceiving sign language, although non-native signers looked significantly more at the body than native signers. This distribution of gaze fixations suggested that deaf individuals - particularly native signers - mainly perceived signs through peripheral vision.

[Discourse analysis: research potentialities to gender violence].

PubMed

de Azambuja, Mariana Porto Ruwer; Nogueira, Conceição

2009-01-01

In the last few years we see the growing use of the terms 'discourse' and 'discourses analysis' in academic and research contexts, frequently without a precise definition. This fact opens space for critics and mistakes. The aim of this paper is to show a brief contextualization of discursive studies, as well as tasks/steps to Discourse Analysis process by the Social Construcionism perspective. As examples we used fragments of an interview with a Family Doctor about gender violence. In the results we detach the potential of Discourse Analysis to deconstruct the existing discourses to subsequently (re)construction in the way to a more holistic view about gender violence problem.

"Hell no, they'll think you're mad as a hatter": Illness discourses and their implications for patients in mental health practice.

PubMed

Ringer, Agnes; Holen, Mari

2016-03-01

This article examines how discourses on mental illness are negotiated in mental health practice and their implications for the subjective experiences of psychiatric patients. Based on a Foucauldian analysis of ethnographic data from two mental health institutions in Denmark--an outpatient clinic and an inpatient ward--this article identifies three discourses in the institutions: the instability discourse, the discourse of "really ill," and the lack of insight discourse. This article indicates that patients were required to develop a finely tuned and precise sense of the discourses and ways to appear in front of professionals if they wished to have a say in their treatment. We suggest that the extent to which an individual patient was positioned as ill seemed to rely more on his or her ability to navigate the discourses and the psychiatric setting than on any objective diagnostic criteria. Thus, we argue that illness discourses in mental health practice are not just materialized as static biomedical understandings, but are complex and diverse--and have implications for patients' possibilities to understand themselves and become understandable to professionals. © The Author(s) 2015.

Citation Analysis and Discourse Analysis Revisited

ERIC Educational Resources Information Center

White, Howard D.

2004-01-01

John Swales's 1986 article "Citation analysis and discourse analysis" was written by a discourse analyst to introduce citation research from other fields, mainly sociology of science, to his own discipline. Here, I introduce applied linguists and discourse analysts to citation studies from information science, a complementary tradition not…

Discourse Communities--Local and Global.

ERIC Educational Resources Information Center

Killingsworth, M. Jimmie

1992-01-01

Argues that rhetorical theory needs to keep alive competing concepts of discourse communities, so that alternatives exist in the description and analysis of discourse practices. Proposes distinguishing between two kinds of discourse communities--the local and the global--so that rhetorical analysis can achieve the necessary critical edge,…

The Language and Politics of Exclusion: Others in Discourse.

ERIC Educational Resources Information Center

Riggins, Stephen Harold, Ed.

A collection of essays on "the other" in discourse includes: "The Rhetoric of Othering" (Stephen Harold Riggins); "Political Discourse and Racism: Describing Others in Western Parliaments" (Teun A. van Dijk); "'Das Ausland' and Anti-Semitic Discourse: The Discursive Construction of the Other" (Ruth Wodak);…

Assessing the Validity of Discourse Analysis: Transdisciplinary Convergence

ERIC Educational Resources Information Center

Jaipal-Jamani, Kamini

2014-01-01

Research studies using discourse analysis approaches make claims about phenomena or issues based on interpretation of written or spoken text, which includes images and gestures. How are findings/interpretations from discourse analysis validated? This paper proposes transdisciplinary convergence as a way to validate discourse analysis approaches to…

Analysis of core-periphery organization in protein contact networks reveals groups of structurally and functionally critical residues.

PubMed

Isaac, Arnold Emerson; Sinha, Sitabhra

2015-10-01

The representation of proteins as networks of interacting amino acids, referred to as protein contact networks (PCN), and their subsequent analyses using graph theoretic tools, can provide novel insights into the key functional roles of specific groups of residues. We have characterized the networks corresponding to the native states of 66 proteins (belonging to different families) in terms of their core-periphery organization. The resulting hierarchical classification of the amino acid constituents of a protein arranges the residues into successive layers - having higher core order - with increasing connection density, ranging from a sparsely linked periphery to a densely intra-connected core (distinct from the earlier concept of protein core defined in terms of the three-dimensional geometry of the native state, which has least solvent accessibility). Our results show that residues in the inner cores are more conserved than those at the periphery. Underlining the functional importance of the network core, we see that the receptor sites for known ligand molecules of most proteins occur in the innermost core. Furthermore, the association of residues with structural pockets and cavities in binding or active sites increases with the core order. From mutation sensitivity analysis, we show that the probability of deleterious or intolerant mutations also increases with the core order. We also show that stabilization centre residues are in the innermost cores, suggesting that the network core is critically important in maintaining the structural stability of the protein. A publicly available Web resource for performing core-periphery analysis of any protein whose native state is known has been made available by us at http://www.imsc.res.in/ ~sitabhra/proteinKcore/index.html.

Revisited microanatomy of the corneal endothelial periphery: new evidence for continuous centripetal migration of endothelial cells in humans.

PubMed

He, Zhiguo; Campolmi, Nelly; Gain, Philippe; Ha Thi, Binh Minh; Dumollard, Jean-Marc; Duband, Sébastien; Peoc'h, Michel; Piselli, Simone; Garraud, Olivier; Thuret, Gilles

2012-11-01

The control of corneal transparency depends on the integrity of its endothelial monolayer, which is considered nonregenerative in adult humans. In pathological situations, endothelial cell (EC) loss, not offset by mitosis, can lead to irreversible corneal edema and blindness. However, the hypothesis of a slow, clinically insufficient regeneration starting from the corneal periphery remains debatable. The authors have re-evaluated the microanatomy of the endothelium in order to identify structures likely to support this homeostasis model. Whole endothelia of 88 human corneas (not stored, and stored in organ culture) with mean donor age of 80 ± 12 years were analyzed using an original flat-mounting technique. In 61% of corneas, cells located at the extreme periphery (last 200 μm of the endothelium) were organized in small clusters with two to three cell layers around Hassall-Henle bodies. In 68% of corneas, peripheral ECs formed centripetal rows 830 ± 295 μm long, with Descemet membrane furrows visible by scanning electron microscopy. EC density was significantly higher in zones with cell rows. When immunostained, ECs in the extreme periphery exhibited lesser differentiation (ZO-1, Actin, Na/K ATPase, CoxIV) than ECs in the center of the cornea but preferentially expressed stem cell markers (Nestin, Telomerase, and occasionally breast cancer resistance protein) and, in rare cases, the proliferation marker Ki67. Stored corneas had fewer cell clusters but more Ki67-positive ECs. We identified a novel anatomic organization in the periphery of the human corneal endothelium, suggesting a continuous slow centripetal migration, throughout life, of ECs from specific niches. Copyright © 2012 AlphaMed Press.

Region-specific ischemia, neovascularization and macular oedema in treatment-naïve proliferative diabetic retinopathy.

PubMed

Lange, Jason; Hadziahmetovic, Majda; Zhang, Jingfa; Li, Weiye

2018-02-07

Region-specific pathology in proliferative diabetic retinopathy enhances our understanding and management of this disease. To investigate non-perfusion, neovascularization and macular oedema. A cross-sectional, observational, non-randomized study. Consecutive 43 eyes of 27 treatment-naïve patients. Ultra-widefield fluorescein angiography for studying specific zones, that is, far-peripheral zone, mid-peripheral zone and central retina (cr), and spectral-domain optical coherence tomography for analysing thickness of macular layers. Non-perfusion index (NPI) and neovascularization index (NVI) in different zones, thickness of cr, retinal nerve fibre layer, ganglion cell layer (GCL), inner nuclear layer (INL) and outer plexiform layer in parafoveal regions. The NPI of far-periphery and NVI of mid-periphery were the highest by one-way analysis of variance testing. Ischemic retina defined as high NPI in far-periphery was significantly related to macular oedema via a binary classification approach (P < 0.05). The ischemic retina was correlated with a decreased thickness of both retinal nerve fibre and GCL (P < 0.05); macular oedema was correlated with increased INL thickness (P < 0.0001). The region-specific correlation of NPI of far-periphery and NVI of mid-periphery, but not with central retinal thickness, suggests different pathogeneses of neovascularization and macular oedema. Retinal nerve fibre layer and GCL, both biomarkers of diabetic retinal neuronopathy, are associated with retinal ischemia, but not with macular oedema, suggesting that diabetic microangiopathy and neuronopathy possess distinct pathogenic pathways. The strong correlation between macular oedema and INL indicates that intracellular oedema is a determining factor of diabetic macular oedema. © 2018 Royal Australian and New Zealand College of Ophthalmologists.

Roles, intents, and actions: First-year teachers' uses of discourse during elementary science instruction

NASA Astrophysics Data System (ADS)

Newman, William J., Jr.

In this study, I examined how three first-year elementary teachers constructed and used classroom discourse during science instruction. The three participants, though graduates from different universities, learned to teach science through similar science methods courses, which stressed the importance of inquiry-based science instruction. The participants taught different grade levels, and two of them taught at the same school. Data sources included field notes, videotapes, audiotapes, and semi-structured teacher interviews. While monologic and dialogic discourse existed in all three classrooms, monologic discourse was more prominent, especially when the discourse was teacher controlled. Dialogic discourse occurred most often during student-centered activities. The teachers constructed discourse with authoritative function to present science content and determine student comprehension. Generative function was most likely during student-based small group discussions. Monologic character often aligned with authoritative function, and dialogic character often aligned with generative function. However, monologic/generative and dialogic/authoritative discourse events did occur, contributing to the development of a discourse theory model. The teacher explanations for discourse included classroom control, inadequate planning, time constraints, life experiences, science education standards, and assessment. The teachers relied on their texts, kits, and state science standards to determine the content and methods for science instruction. They rarely reported that their science methods courses influenced how they taught science. The observed lessons rarely aligned with science education reform descriptions of appropriate science instruction. Implications include the need for in-service programs for beginning science teachers, curricular reform for science texts and kits, and explicit instruction of discourse strategies in science methods courses and in-service programs.

Wnt and FGF signals interact to coordinate growth with cell fate specification during limb development.

PubMed

ten Berge, Derk; Brugmann, Samantha A; Helms, Jill A; Nusse, Roel

2008-10-01

A fundamental question in developmental biology is how does an undifferentiated field of cells acquire spatial pattern and undergo coordinated differentiation? The development of the vertebrate limb is an important paradigm for understanding these processes. The skeletal and connective tissues of the developing limb all derive from a population of multipotent progenitor cells located in its distal tip. During limb outgrowth, these progenitors segregate into a chondrogenic lineage, located in the center of the limb bud, and soft connective tissue lineages located in its periphery. We report that the interplay of two families of signaling proteins, fibroblast growth factors (FGFs) and Wnts, coordinate the growth of the multipotent progenitor cells with their simultaneous segregation into these lineages. FGF and Wnt signals act together to synergistically promote proliferation while maintaining the cells in an undifferentiated, multipotent state, but act separately to determine cell lineage specification. Withdrawal of both signals results in cell cycle withdrawal and chondrogenic differentiation. Continued exposure to Wnt, however, maintains proliferation and re-specifies the cells towards the soft connective tissue lineages. We have identified target genes that are synergistically regulated by Wnts and FGFs, and show how these factors actively suppress differentiation and promote growth. Finally, we show how the spatial restriction of Wnt and FGF signals to the limb ectoderm, and to a specialized region of it, the apical ectodermal ridge, controls the distribution of cell behaviors within the growing limb, and guides the proper spatial organization of the differentiating tissues.

Transit Oriented Development (TOD) index at the current transit nodes in Depok City, Indonesia

NASA Astrophysics Data System (ADS)

Sulistyaningrum, Subekti; Sumabrata, Jachrizal

2018-03-01

Depok is a rural area which developed by Perum Perumnas in 1976. And growth rapidly since University of Indonesia moved in 1986. Afterward, Depok became a new city at periphery of DKI Jakarta with numerous development and urbanizations. Depok city is facing urban problems including population growth of 9% per year, the increasing regular and irregular settlements and transportation problems such as traffic congestion, the increasing of individual cars and motorcycles and lack of transportation development. Moreover, Jabodetabek Commuterline which is start from Bogor station and transits in 5 (five) stations in Depok city (Universitas Indonesia, Pondok Cina, Depok Baru, Depok and Citayam), become a potential alternative for commuters in Depok to go out of the city. Depok should have sustainable transportation such as Transit Oriented Development (TOD) masterplan in a strategic place of railways area to conduct a sustainable city. This study discovered that TOD planning should be proceded by understanding the existing condition through measurement of TOD level. Therefore, the measurement of TOD level around the existing nodes is inevitable as transit node plays a central role in TOD, so it was defined as 800 meters walking distances. This paper focus on 3 (three) station areas along the way of Jalan Margonda, which has a very significant growth development area in Depok with the indicators are devided into spatial and non-spatial indicators. Geographic Information Systems (ArcGIS) isused to quantify all of the spatial indicators.

A low-dimensional approach to closed-loop control of a Mach 0.6 jet

NASA Astrophysics Data System (ADS)

Low, Kerwin R.; Berger, Zachary P.; Kostka, Stanislav; ElHadidi, Basman; Gogineni, Sivaram; Glauser, Mark N.

2013-04-01

Simultaneous time-resolved measurements of the near-field hydrodynamic pressure field, 2-component streamwise velocity field, and far-field acoustics are taken for an un-heated, axisymmetric Mach 0.6 jet in co-flow. Synthetic jet actuators placed around the periphery of the nozzle lip provide localized perturbations to the shear layer. The goal of this study was to develop an understanding of how the acoustic nature of the jet responds to unsteady shear layer excitation, and subsequently how this can be used to reduce the far-field noise. Review of the cross-correlations between the most energetic low-order spatial Fourier modes of the pressure and the far-field region reveals that mode 0 has a strong correlation and mode 1 has a weak correlation with the far-field. These modes are emulated with the synthetic jet array and used as drivers of the developing shear layer. In open loop forcing configurations, there is energy transfer among spatial scales, enhanced mixing, a reconfiguration of the low-dimensional spatial structure, and an increase in the overall sound pressure level (OASPL). In the closed loop configuration, changes to these quantities are more subtle but there is a reduction in the overall fluctuating sound pressure level OASPLf by 1.35 dB. It is argued that this reduction is correlated with the closed loop control feeding back the dynamical low-order information measured in the largest noise producing region.

Video Game Discourses and Implications for Game-Based Education

ERIC Educational Resources Information Center

Whitton, Nicola; Maclure, Maggie

2017-01-01

Increasingly prevalent educational discourses promote the use of video games in schools and universities. At the same time, populist discourses persist, particularly in print media, which condemn video games because of putative negative effects on behaviour and socialisation. These contested discourses, we suggest, influence the acceptability of…

Composition Instructors' Interactions with Classroom Discourse Communities: A Qualitative Study

ERIC Educational Resources Information Center

Winterberg, Sarah Griffith

2017-01-01

This study offered insight on the intermingling of discourse communities in the learning environment by examining experiences of composition instructors from a regional Southern university and their reflections of teaching students who struggled to navigate from home discourse to academic discourse. Merriam's basic qualitative research design…

Multimodal Discourse Analysis of the Movie "Argo"

ERIC Educational Resources Information Center

Bo, Xu

2018-01-01

Based on multimodal discourse theory, this paper makes a multimodal discourse analysis of some shots in the movie "Argo" from the perspective of context of culture, context of situation and meaning of image. Results show that this movie constructs multimodal discourse through particular context, language and image, and successfully…

Discourse Analysis and the Study of Educational Leadership

ERIC Educational Resources Information Center

Anderson, Gary; Mungal, Angus Shiva

2015-01-01

Purpose: The purpose of this paper is to provide an overview of the current and past work using discourse analysis in the field of educational administration and of discourse analysis as a methodology. Design/Methodology/Approach: Authors reviewed research in educational leadership that uses discourse analysis as a methodology. Findings: While…

The Discourse of Classroom Interaction in Kenyan Primary Schools

ERIC Educational Resources Information Center

Pontefract, Caroline; Hardman, Frank

2005-01-01

This paper addresses the role of classroom discourse in supporting children's learning in Kenyan primary schools. The discourse strategies of 27 teachers teaching English, mathematics and science across the primary phase were intensively studied using discourse analysis and semi-structured interviews. A survey questionnaire (n = 359) was also used…

A Sexuality Education Discourses Framework: Conservative, Liberal, Critical, and Postmodern

ERIC Educational Resources Information Center

Jones, Tiffany

2011-01-01

Sexuality education debates are layered with discourses based on markedly different constructions of sexuality. Rather than seeing these discourses as purely oppositional, this article frames them as complex and varied. It provides a new framework for understanding sexuality education which differentiates 28 discourses by orientation to education,…

Language, Power and Identity

ERIC Educational Resources Information Center

Wodak, Ruth

2012-01-01

How are identities constructed in discourse? How are national and European identities tied to language and communication? And what role does power have--power in discourse, over discourse and of discourse? This paper seeks to identify and analyse processes of identity construction within Europe and at its boundaries, particularly the diversity of…

Reviewing the Quality of Discourse Information Measures in Aphasia

ERIC Educational Resources Information Center

Pritchard, Madeleine; Hilari, Katerina; Cocks, Naomi; Dipper, Lucy

2017-01-01

Background: Discourse is fundamental to everyday communication, and is an increasing focus of clinical assessment, intervention and research. Aphasia can affect the information a speaker communicates in discourse. Little is known about the psychometrics of the tools for measuring information in discourse, which means it is unclear whether these…

The Construction of Pro-Science and Technology Discourse in Chinese Language Textbooks

ERIC Educational Resources Information Center

Liu, Yongbing

2005-01-01

This paper examines the pro-science and technology discourse constructed in Chinese language textbooks currently used for primary school students nationwide in China. By applying analytical techniques of critical discourse analysis (CDA), the paper critically investigates how the discourse is constructed and what ideological forces are manifested…

Discourses from without, Discourses from Within: Women, Feminism and Voice in Africa

ERIC Educational Resources Information Center

Heugh, Kathleen

2011-01-01

Discourses of development, education, gender, feminism and critical linguistics arrive in Africa from usually well-meaning but often opportunistic agents from other contemporary socio-political and economic contexts. Each of these forms a new layer that veils the earlier discourses and practices. Simultaneously, people in Africa are…

Addressing Racialized Multicultural Discourses in an EAP Textbook: Working toward a Critical Pedagogies Approach

ERIC Educational Resources Information Center

Chun, Christian W.

2016-01-01

Racialized multicultural discourses emerge in the TESOL classroom via textbook representations of immigrant success stories and perceived racial and cultural differences among students. Although liberal multicultural discourses may be well intentioned, these discourses warrant closer examination for the ways in which they can essentialize cultural…

Critical Narrative Analysis: The Interplay of Critical Discourse and Narrative Analyses

ERIC Educational Resources Information Center

Souto-Manning, Mariana

2014-01-01

In this article, I question the micro-macro separation in discourse analysis, the separation of personal and institutional discourses. I apply a mostly macroanalytic perspective (critical discourse analysis [CDA]) to inform a predominantly microanalytic perspective (analysis of conversational narratives) and vice versa. In the combination of these…

Counselor-Advocate-Scholar Model: Changing the Dominant Discourse in Counseling

ERIC Educational Resources Information Center

Ratts, Manivong J.; Greenleaf, Arie T.

2018-01-01

Discourse represents the languages, ideas, and images that together shape one's understanding of the world. In counseling, discourse determines clinical practice. The authors posit that dominant discourse in counseling promotes an intrapsychic status quo that discounts the relationship between individuals and their environment, which often leads…

Gender, Discourse, and "Gender and Discourse."

ERIC Educational Resources Information Center

Davis, Hayley

1997-01-01

A critic of Deborah Tannen's book "Gender and Discourse" responds to comments made about her critique, arguing that the book's analysis of the relationship of gender and discourse tends to seek, and perhaps force, explanations only in those terms. Another linguist's analysis of similar phenomena is found to be more rigorous. (MSE)

From Tragedy to Comedy: Reframing Contemporary Discourses

ERIC Educational Resources Information Center

Broom, Catherine

2011-01-01

This paper argues that environmental destruction arises from a discourse rooted in Western Economic and Scientific Theory. This discourse artificially separates individuals from our natural world and argues that competition and utilitarian actions are beneficial to society. It is however, a discourse that is taking us to a Shakespearean tragic…

Useful and Dangerous Discourse: Deconstructing Racialized Knowledge about African-American Students

ERIC Educational Resources Information Center

Brown, Keffrelyn D.; Brown, Anthony L.

2012-01-01

Drawing from Michel Foucault's notion of "useful" and "dangerous" discourse coupled with the theory of racial knowledge, this article examines how two common counter-discourses about African-American students operate and create racial knowledge in education practice. By "counter-discourse", the authors refer to knowledge, theories, and histories…

Lexical Discourse Analysis in Translation

ERIC Educational Resources Information Center

Al Khotaba, Eissa; Al Tarawneh, Khaled

2015-01-01

Lexical Discourse very often depend on lexis. Lexical Discourse analysis, however, has not yet been given enough consideration of the phenomenon of translation. This paper investigates lexical discourse analysis in translation from one language to another. This qualitative study comprises 15 text translated by M.A. students at the Department of…

Excited atoms in the free-burning Ar arc: treatment of the resonance radiation

NASA Astrophysics Data System (ADS)

Golubovskii, Yu; Kalanov, D.; Gortschakow, S.; Baeva, M.; Uhrlandt, D.

2016-11-01

The collisional-radiative model with an emphasis on the accurate treatment of the resonance radiation transport is developed and applied to the free-burning Ar arc plasma. This model allows for analysis of the influence of resonance radiation on the spatial density profiles of the atoms in different excited states. The comparison of the radial density profiles obtained using an effective transition probability approximation with the results of the accurate solution demonstrates the distinct impact of transport on the profiles and absolute densities of the excited atoms, especially in the arc fringes. The departures from the Saha-Boltzmann equilibrium distributions, caused by different radiative transitions, are analyzed. For the case of the DC arc, the local thermodynamic equilibrium (LTE) state holds close to the arc axis, while strong deviations from the equilibrium state on the periphery occur. In the intermediate radial positions the conditions of partial LTE are fulfilled.

The Morphology of the X-ray Emission above 2 keV from Jupiter's Aurorae

NASA Technical Reports Server (NTRS)

Elsner, R.; Branduardi-Raymont, G.; Galand, M.; Grodent, D.; Gladstone, G. R.; Waite, J. H.; Cravens, T.; Ford, P.

2007-01-01

The discovery in XMM-Newton X-ray data of X-ray emission above 2 keY from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E < 1 keV. We are presently exploring the relationship of this morphology to that of the FUV emission from the main auroral oval and the polar cap. The low energy emission has previously been established as due to charge exchange between energetic precipitating ions of oxygen and either sulfur or carbon. It seems likely to us that the higher energy emission is due to precipitation of energetic electrons, possibly the same population of electrons responsible for the FUV emission. We discuss our analysis and interpretation.

The Morphology of the X-ray Emission above 2 keV from Jupiter's Aurorae

NASA Technical Reports Server (NTRS)

Elsner, R.; Branduardi-Raymont, G.; Galand, M.; Grodent, D.; Waite, J. H.; Cravens, T.; Ford, P.

2007-01-01

The discovery in XMM-Newton X-ray data of X-ray emission above 2 keV from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E < 1 keV. We are presently exploring the relationship of this morphology to that of the FUV emission from the main auroral oval and the polar cap. The low energy emission has previously been established as due to charge exchange between energetic precipitating ions of oxygen and either sulfur or carbon. It seems likely to us that the higher energy emission is due to precipitation of energetic electrons, possibly the same population of electrons responsible for the FUV emission. We discuss our analysis and interpretation.

Modification of ordinary-mode reflectometry system to detect lower-hybrid waves in Alcator C-Mod

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

Baek, S. G.; Shiraiwa, S.; Parker, R. R.

2012-10-15

Backscattering experiments to detect lower-hybrid (LH) waves have been performed in Alcator C-Mod, using the two modified channels (60 GHz and 75 GHz) of an ordinary-mode reflectometry system with newly developed spectral recorders that can continuously monitor spectral power at a target frequency. The change in the baseline of the spectral recorder during the LH wave injection is highly correlated to the strength of the X-mode non-thermal electron cyclotron emission. In high density plasmas where an anomalous drop in the lower hybrid current drive efficiency is observed, the observed backscattered signals are expected to be generated near the last closedmore » flux surface, demonstrating the presence of LH waves within the plasma. This experimental technique can be useful in identifying spatially localized LH electric fields in the periphery of high-density plasmas.« less

Nuclear networking.

PubMed

Xie, Wei; Burke, Brian

2017-07-04

Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

State-space receptive fields of semicircular canal afferent neurons in the bullfrog

NASA Technical Reports Server (NTRS)

Paulin, M. G.; Hoffman, L. F.

2001-01-01

Receptive fields are commonly used to describe spatial characteristics of sensory neuron responses. They can be extended to characterize temporal or dynamical aspects by mapping neural responses in dynamical state spaces. The state-space receptive field of a neuron is the probability distribution of the dynamical state of the stimulus-generating system conditioned upon the occurrence of a spike. We have computed state-space receptive fields for semicircular canal afferent neurons in the bullfrog (Rana catesbeiana). We recorded spike times during broad-band Gaussian noise rotational velocity stimuli, computed the frequency distribution of head states at spike times, and normalized these to obtain conditional pdfs for the state. These state-space receptive fields quantify what the brain can deduce about the dynamical state of the head when a single spike arrives from the periphery. c2001 Elsevier Science B.V. All rights reserved.

Shallow Melt Apparatus for Semicontinuous Czochralski Crystal Growth

DOEpatents

Wang, T.; Ciszek, T. F.

2006-01-10

In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

Measured Visual Motion Sensitivity at Fixed Contrast in the Periphery and Far Periphery

DTIC Science & Technology

2017-08-01

group Soldier performance. Soldier performance depends on visual detection of enemy personnel and materiel. Vision modeling in IWARS is neither...a highly time-critical and order- dependent activity, these unrealistic characterizations of target detection time and order severely limit the...recognize that MVTs should depend on target contrast, so we selected a target design different from that used in the Monaco et al. (2007) study. Based

Adults with Dyslexia Demonstrate Space-Based and Object-Based Covert Attention Deficits: Shifting Attention to the Periphery and Shifting Attention between Objects in the Left Visual Field

ERIC Educational Resources Information Center

Buchholz, J.; Davies, A.A.

2005-01-01

Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was…

Combined effect of BCG vaccination and enriched environment promote neurogenesis and spatial cognition via a shift in meningeal macrophage M2 polarization.

PubMed

Qi, Fangfang; Zuo, Zejie; Yang, Junhua; Hu, Saisai; Yang, Yang; Yuan, Qunfang; Zou, Juntao; Guo, Kaihua; Yao, Zhibin

2017-02-10

The spatial learning abilities of developing mice benefit from extrinsic cues, such as an enriched environment, with concomitant enhancement in cognitive functions. Interestingly, such enhancements can be further increased through intrinsic Bacillus Calmette-Guérin (BCG) vaccination. Here, we first report that combined neonatal BCG vaccination and exposure to an enriched environment (Enr) induced combined neurobeneficial effects, including hippocampal long-term potentiation, and increased neurogenesis and spatial learning and memory, in mice exposed to the Enr and vaccinated with BCG relative to those in the Enr that did not receive BCG vaccination. Neonatal BCG vaccination markedly induced anti-inflammatory meningeal macrophage polarization both in regular and Enr breeding mice. The meninges are composed of the pia mater, dura mater, and choroid plexus. Alternatively, this anti-inflammatory activity of the meninges occurred simultaneously with increased expression of the neurotrophic factors BDNF/IGF-1 and the M2 microglial phenotype in the hippocampus. Our results reveal a critical role for BCG vaccination in the regulation of neurogenesis and spatial cognition through meningeal macrophage M2 polarization and neurotrophic factor expression; these effects were completely or partially prevented by minocycline or anti-IL-10 antibody treatment, respectively. Together, we first claim that immunological factor and environmental factor induce a combined effect on neurogenesis and cognition via a common pathway-meningeal macrophage M2 polarization. We also present a novel functional association between peripheral T lymphocytes and meningeal macrophages after evoking adaptive immune responses in the periphery whereby T lymphocytes are recruited to the meninges in response to systemic IFN-γ signaling. This leads to meningeal macrophage M2 polarization, subsequent to microglial M2 activation and neurotrophic factor expression, and eventually promotes a positive behavior.

Network analysis of exploratory behaviors of mice in a spatial learning and memory task

PubMed Central

Suzuki, Yusuke

2017-01-01

The Barnes maze is one of the main behavioral tasks used to study spatial learning and memory. The Barnes maze is a task conducted on “dry land” in which animals try to escape from a brightly lit exposed circular open arena to a small dark escape box located under one of several holes at the periphery of the arena. In comparison with another classical spatial learning and memory task, the Morris water maze, the negative reinforcements that motivate animals in the Barnes maze are less severe and less stressful. Furthermore, the Barnes maze is more compatible with recently developed cutting-edge techniques in neural circuit research, such as the miniature brain endoscope or optogenetics. For this study, we developed a lift-type task start system and equipped the Barnes maze with it. The subject mouse is raised up by the lift and released into the maze automatically so that it can start navigating the maze smoothly from exactly the same start position across repeated trials. We believe that a Barnes maze test with a lift-type task start system may be useful for behavioral experiments when combined with head-mounted or wire-connected devices for online imaging and intervention in neural circuits. Furthermore, we introduced a network analysis method for the analysis of the Barnes maze data. Each animal’s exploratory behavior in the maze was visualized as a network of nodes and their links, and spatial learning in the maze is described by systematic changes in network structures of search behavior. Network analysis was capable of visualizing and quantitatively analyzing subtle but significant differences in an animal’s exploratory behavior in the maze. PMID:28700627

Identification of a core-periphery structure among participants of a business climate survey. An investigation based on the ZEW survey data

NASA Astrophysics Data System (ADS)

Stolzenburg, U.; Lux, T.

2011-12-01

Processes of social opinion formation might be dominated by a set of closely connected agents who constitute the cohesive `core' of a network and have a higher influence on the overall outcome of the process than those agents in the more sparsely connected `periphery'. Here we explore whether such a perspective could shed light on the dynamics of a well known economic sentiment index. To this end, we hypothesize that the respondents of the survey under investigation form a core-periphery network, and we identify those agents that define the core (in a discrete setting) or the proximity of each agent to the core (in a continuous setting). As it turns out, there is significant correlation between the so identified cores of different survey questions. Both the discrete and the continuous cores allow an almost perfect replication of the original series with a reduced data set of core members or weighted entries according to core proximity. Using a monthly time series on industrial production in Germany, we also compared experts' predictions with the real economic development. The core members identified in the discrete setting showed significantly better prediction capabilities than those agents assigned to the periphery of the network.

Seeing number using texture: How summary statistics account for reductions in perceived numerosity in the visual periphery.

PubMed

Balas, Benjamin

2016-11-01

Peripheral visual perception is characterized by reduced information about appearance due to constraints on how image structure is represented. Visual crowding is a consequence of excessive integration in the visual periphery. Basic phenomenology of visual crowding and other tasks have been successfully accounted for by a summary-statistic model of pooling, suggesting that texture-like processing is useful for how information is reduced in peripheral vision. I attempt to extend the scope of this model by examining a property of peripheral vision: reduced perceived numerosity in the periphery. I demonstrate that a summary-statistic model of peripheral appearance accounts for reduced numerosity in peripherally viewed arrays of randomly placed dots, but does not account for observed effects of dot clustering within such arrays. The model thus offers a limited account of how numerosity is perceived in the visual periphery. I also demonstrate that the model predicts that numerosity estimation is sensitive to element shape, which represents a novel prediction regarding the phenomenology of peripheral numerosity perception. Finally, I discuss ways to extend the model to a broader range of behavior and the potential for using the model to make further predictions about how number is perceived in untested scenarios in peripheral vision.

The locus control region is required for association of the murine β-globin locus with engaged transcription factories during erythroid maturation

PubMed Central

Ragoczy, Tobias; Bender, M.A.; Telling, Agnes; Byron, Rachel; Groudine, Mark

2006-01-01

We have examined the relationship between nuclear localization and transcriptional activity of the endogenous murine β-globin locus during erythroid differentiation. Murine fetal liver cells were separated into distinct erythroid maturation stages by fluorescence-activated cell sorting, and the nuclear position of the locus was determined at each stage. We find that the β-globin locus progressively moves away from the nuclear periphery with increasing maturation. Contrary to the prevailing notion that the nuclear periphery is a repressive compartment in mammalian cells, βmajor-globin expression begins at the nuclear periphery prior to relocalization. However, relocation of the locus to the nuclear interior with maturation is accompanied by an increase in βmajor-globin transcription. The distribution of nuclear polymerase II (Pol II) foci also changes with erythroid differentiation: Transcription factories decrease in number and contract toward the nuclear interior. Moreover, both efficient relocalization of the β-globin locus from the periphery and its association with hyperphosphorylated Pol II transcription factories require the locus control region (LCR). These results suggest that the LCR-dependent association of the β-globin locus with transcriptionally engaged Pol II foci provides the driving force for relocalization of the locus toward the nuclear interior during erythroid maturation. PMID:16705039

The effect of shear wall location in resisting earthquake

NASA Astrophysics Data System (ADS)

Tarigan, J.; Manggala, J.; Sitorus, T.

2018-02-01

Shear wall is one of lateral resisting structure which is used commonly. Shear wall gives high stiffness to the structure so as the structure will be stable. Applying shear wall can effectively reduce the displacement and story-drift of the structure. This will reduce the destruction comes from lateral loads such as an earthquake. Earlier studies showed that shear wall gives different performance based on its position in structures. In this paper, seismic analysis has been performed using response spectrum method for different Model of structures; they are the open frame, the shear wall at core symmetrically, the shear wall at periphery symmetrically, and the shear wall at periphery asymmetrically. The results are observed by comparing the displacement and story-drift. Based on the analysis, the placement of shear wall at the core of structure symmetrically gives the best performance to reduce the displacement and story-drift. It can reduce the displacement up to 61.16% (X-dir) and 70.60% (Y-dir). The placement of shear wall at periphery symmetrically will reduce the displacement up to 53.85% (X-dir) and 47.87% (Y-dir) while the placement of shear wall at periphery asymmetrically reducing the displacement up to 59.42% (X-dir) and 66.99% (Y-dir).

Spatial memory: a Rosetta stone for rat and human hippocampal discourse: Theoretical comment on Goodrich-Hunsaker and Hopkins (2010).

PubMed

Sutherland, Robert J

2010-06-01

The article by Goodrich-Hunsaker and Hopkins (2010, this issue) takes up an important place among in the recent contributions on the role of the hippocampus in memory. They evaluate the effect of bilateral damage to the hippocampus on performance by human participants in a virtual 8-arm radial maze. The hippocampal damage appears to be highly selective and nearly complete. Exactly as with selective hippocampal damage in rats, the human participants showed a deficit in accurately choosing rewarded versus never-rewarded arms and a deficit in avoiding reentering recently visited arms. The results are triply significant: (1) They provide good support for the idea that the wealth of neurobiological information, from network to synapse to gene, on spatial memory in the rat may apply as a whole to the human hippocampal memory system; (2) They affirm the utility of human virtual task models of rat spatial memory tasks; (3) They support one interpretation of the dampening of the hippocampal functional MRI (fMRI) blood oxygen level-dependent (BOLD) signal during performance of the virtual radial arm maze observed by Astur et al. (2005).

"I Wanted to Rebel, But There They Hit Me Even Harder": Discourse Analysis of Israeli Women Offenders' Accounts of Their Pathways to Substance Abuse and Crime.

PubMed

Gueta, Keren; Chen, Gila

2016-05-01

This study examined women offenders' accounts of their pathways to substance abuse and crime and the intersection between them, to reach a holistic understanding that captures the dynamics of victimization, agency, and gender. Discourse analyses of the accounts of 11 Israeli women offenders indicated differential use of two discourses. Five participants used the victimization discourse, which viewed substance abuse as an attempt to medicate the self that was injured following victimization experiences; two used the agency discourse, which viewed substance abuse as a way to experience pleasure, leisure, and control over their destiny. Four of the participants used these two contradictory discourses simultaneously. The findings indicate the absence of a cultural discourse that encompasses women's complex experience of gender, victimization, and agency. Possible implications for intervention are discussed. © The Author(s) 2015.

Well, Now, Okey Dokey: English Discourse Markers in Spanish Language Medical Consultations

PubMed Central

Vickers, Caroline H.; Goble, Ryan

2013-01-01

The purpose of this paper is to examine use of English discourse markers in otherwise Spanish language consultations. Data is derived from an audio-recorded corpus of Spanish language consultations that took place in a small community clinic in the United States as well as post-consultation interviews with patients and providers. Through quantification of the use of discourse makers in the corpus and discourse analysis of transcripts, we demonstrate that English-speaking dominant medical providers use English discourse markers more frequently and with a broader range of functions than do Spanish-speaking dominant medical providers and patients. We argue that such use of English discourse markers serves to exacerbate the power relationship between providers and patients even though the use of English discourse markers does not cause overt miscommunication in the ongoing interaction. Implications for providers who use a second language in their medical consultations are discussed. PMID:24347670

Dose Distribution in Cone-Beam Breast Computed Tomography: An Experimental Phantom Study

NASA Astrophysics Data System (ADS)

Russo, Paolo; Lauria, Adele; Mettivier, Giovanni; Montesi, Maria Cristina; Villani, Natalia

2010-02-01

We measured the spatial distribution of absorbed dose in a 14 cm diameter PMMA half-ellipsoid phantom simulating the uncompressed breast, using an X-ray cone-beam breast computed tomography apparatus, assembled for laboratory tests. Thermoluminescent dosimeters (TLD-100) were placed inside the phantom in six positions, both axially and at the phantom periphery. To study the dose distribution inside the PMMA phantom two experimental setups were adopted with effective energies in the range 28.7-44.4 keV. Different values of effective energies were obtained by combining different configurations of added Cu filtration (0.05 mm or 0.2 mm) and tube voltages (from 50 kVp to 80 kVp). Dose values obtained by TLDs in different positions inside the PMMA are reported. To evaluate the dose distribution in the breast shaped volume, the values measured were normalized to the one obtained in the inner position inside the phantom. Measurements with a low energy setup show a gradual increment of dose going from the "chest wall" to the "nipple" (63% more at the "nipple" compared to the central position). Likewise, a gradual increment is observed going from the breast axis toward the periphery (82% more at the "skin" compared to the central position). A more uniform distribution of dose inside the PMMA was obtained with a high energy setup (the maximum variation was 33% at 35.5 keV effective energy in the radial direction). The most uniform distribution is obtained at 44.4 keV. The results of this study show how the dose is distributed: it varies as a function of effective energy of the incident X-ray beam and as a function of the position inside the volume (axial or peripheral position).

Gold nanoshell thermal confinement of conformal laser thermal therapy in liver metastasis

NASA Astrophysics Data System (ADS)

Elliott, Andrew M.; Wang, James; Shetty, Anil M.; Schwartz, Jon; Hazle, John D.; Stafford, R. Jason

2008-02-01

Cooled fiber tip technology has significantly improved the volume coverage of laser induced thermal therapy (LITT), making LITT an attractive technology for the minimally invasive treatment of cancer. Gold coated nanoshells can be tuned to experience a plasmon resonance at a desired laser frequency, there introduction into the treatment region can greatly amplify the effectiveness of the thermal treatment. The goal is to conformaly heat the target, while sparing surrounding healthy tissue. To this end a treatment option that is self-confining to the target lesion is highly desirable. This can be achieved in the liver by allowing nanoshells to be taken up by the healthy tissue of the liver as part of their natural removal from the blood stream. The lesion is then incased inside the nanoshell laden tissue of the surrounding healthy tissue. When an interstitial laser probe is introduced into the center of the lesion the thermal radiation scatters outward until it interacts with and is absorbed by the nanoshells located around the lesion periphery. As the periphery heats it acts as secondary source of thermal radiation, sending heat back into lesion and giving rise to ablative temperatures within the lesion while sparing the surrounding tissue. In order to better monitor therapy and know when the target volume has been ablated, or exceeded, accurate knowledge is needed of both the spatial distribution of heating and the maximum temperature achieved. Magnetic resonance temperature imaging (MRTI) is capable of monitoring the spatiotemporal distribution of temperature in vivo[1]. Experiments have been performed in vitro using a dog liver containing nanoshells (concentration 860ppm) and a tissue like lesion phantom designed to have the optical properties of liver metastasis [2].

FLOURY ENDOSPERM7 encodes a regulator of starch synthesis and amyloplast development essential for peripheral endosperm development in rice

PubMed Central

Zhang, Long; Ren, Yulong; Lu, Bingyue; Yang, Chunyan; Feng, Zhiming; Liu, Zhou; Chen, Jun; Ma, Weiwei; Wang, Ying; Yu, Xiaowen; Wang, Yunlong; Zhang, Wenwei; Wang, Yihua; Liu, Shijia; Wu, Fuqing; Zhang, Xin; Guo, Xiuping; Bao, Yiqun; Jiang, Ling; Wan, Jianmin

2016-01-01

In cereal crops, starch synthesis and storage depend mainly on a specialized class of plastids, termed amyloplasts. Despite the importance of starch, the molecular machinery regulating starch synthesis and amyloplast development remains largely unknown. Here, we report the characterization of the rice (Oryza sativa) floury endosperm7 (flo7) mutant, which develops a floury-white endosperm only in the periphery and not in the inner portion. Consistent with the phenotypic alternation in flo7 endosperm, the flo7 mutant had reduced amylose content and seriously disrupted amylopectin structure only in the peripheral endosperm. Notably, flo7 peripheral endosperm cells showed obvious defects in compound starch grain development. Map-based cloning of FLO7 revealed that it encodes a protein of unknown function. FLO7 harbors an N-terminal transit peptide capable of targeting functional FLO7 fused to green fluorescent protein to amyloplast stroma in developing endosperm cells, and a domain of unknown function 1338 (DUF1338) that is highly conserved in green plants. Furthermore, our combined β-glucuronidase activity and RNA in situ hybridization assays showed that the FLO7 gene was expressed ubiquitously but exhibited a specific expression in the endosperm periphery. Moreover, a set of in vivo experiments demonstrated that the missing 32 aa in the flo7 mutant protein are essential for the stable accumulation of FLO7 in the endosperm. Together, our findings identify FLO7 as a unique plant regulator required for starch synthesis and amyloplast development within the peripheral endosperm and provide new insights into the spatial regulation of endosperm development in rice. PMID:26608643

Origin and characteristics of high Shannon entropy at the pivot of locally stable rotors: insights from computational simulation.

PubMed

Ganesan, Anand N; Kuklik, Pawel; Gharaviri, Ali; Brooks, Anthony; Chapman, Darius; Lau, Dennis H; Roberts-Thomson, Kurt C; Sanders, Prashanthan

2014-01-01

Rotors are postulated to maintain cardiac fibrillation. Despite the importance of bipolar electrograms in clinical electrophysiology, few data exist on the properties of bipolar electrograms at rotor sites. The pivot of a spiral wave is characterized by relative uncertainty of wavefront propagation direction compared to the periphery. The bipolar electrograms used in electrophysiology recording encode information on both direction and timing of approaching wavefronts. To test the hypothesis that bipolar electrograms from the pivot of rotors have higher Shannon entropy (ShEn) than electrograms recorded at the periphery due to the spatial dynamics of spiral waves. We studied spiral wave propagation in 2-dimensional sheets constructed using a simple cell automaton (FitzHugh-Nagumo), atrial (Courtemanche-Ramirez-Nattel) and ventricular (Luo-Rudy) myocyte cell models and in a geometric model spiral wave. In each system, bipolar electrogram recordings were simulated, and Shannon entropy maps constructed as a measure of electrogram information content. ShEn was consistently highest in the pivoting region associated with the phase singularity of the spiral wave. This property was consistently preserved across; (i) variation of model system (ii) alterations in bipolar electrode spacing, (iii) alternative bipolar electrode orientation (iv) bipolar electrogram filtering and (v) in the presence of rotor meander. Directional activation plots demonstrated that the origin of high ShEn at the pivot was the directional diversity of wavefront propagation observed in this location. The pivot of the rotor is consistently associated with high Shannon entropy of bipolar electrograms despite differences in action potential model, bipolar electrode spacing, signal filtering and rotor meander. Maximum ShEn is co-located with the pivot for rotors observed in the bipolar electrogram recording mode, and may be an intrinsic property of spiral wave dynamic behaviour.

Spatial Imaging, Speciation, and Quantification of Selenium in theHyperaccumulator Plants Astragalus bisulcatus and Stanleya pinnata

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

Freeman, J.L.; Zhang, L.H.; Marcus, M.A.

2006-09-01

Astragalus bisulcatus and Stanleya pinnata hyperaccumulate selenium (Se) up to 1% of plant dry weight. In the field, Se was mostly present in the young leaves and reproductive tissues of both hyperaccumulators. Microfocused scanning x-ray fluorescence mapping revealed that Se was hyperaccumulated in trichomes in young leaves of A. bisulcatus. None of 10 other elements tested were accumulated in trichomes. Micro x-ray absorption spectroscopy and liquid chromatography-mass spectrometry showed that Se in trichomes was present in the organic forms methylselenocysteine (MeSeCys; 53%) and {gamma}-glutamyl-MeSeCys (47%). In the young leaf itself, there was 30% inorganic Se (selenate and selenite) in additionmore » to 70% MeSeCys. In young S. pinnata leaves, Se was highly concentrated near the leaf edge and surface in globular structures that were shown by energy-dispersive x-ray microanalysis to be mainly in epidermal cells. Liquid chromatography-mass spectrometry revealed both MeSeCys (88%) and selenocystathionine (12%) inside leaf edges. In contrast, both the Se accumulator Brassica juncea and the nonaccumulator Arabidopsis thaliana accumulated Se in their leaf vascular tissues and mesophyll cells. Se in hyperaccumulators appears to be mobile in both the xylem and phloem because Se-treated S. pinnata was found to be highly toxic to phloem-feeding aphids, and MeSeCys was present in the vascular tissues of a S. pinnata young leaf petiole as well as in guttation fluid. The compartmentation of organic selenocompounds in specific storage areas in the plant periphery appears to be a unique property of Se hyperaccumulators. The high concentration of Se in the plant periphery may contribute to Se tolerance and may also serve as an elemental plant defense mechanism.« less

Design, Demand, Development, and Desire: A Symposium on the Discourses of Workplace Learning. Innovative Session.

ERIC Educational Resources Information Center

Dirkx, John M.; Swanson, Richard A.; Watkins, Karen E.; Cseh, Maria

Our understanding of workplace learning is shaped by four dominant discourses that may be labeled the discourses of design, demand, development and desire. Within these different discourses, understanding of workplace learning is shaped and bounded by particular assumptions about the "self in context," which includes the organizational…

English and the Knowledge Economy: A Critical Analysis

ERIC Educational Resources Information Center

Collin, Ross

2014-01-01

This article focuses on knowledge economy discourse and considers the appeal of this discourse to English educators. Knowledge economy discourse is defined as a mode of thought and expression that assumes a broad-based economy driven by innovation will soon emerge in the USA. This discourse, it is argued, offers English teachers solutions to some…

Arguing Collaboratively: Argumentative Discourse Types and Their Potential for Knowledge Building

ERIC Educational Resources Information Center

Felton, Mark; Garcia-Mila, Merce; Villarroel, Constanza; Gilabert, Sandra

2015-01-01

Background: There is growing interest in using argumentative discourse in educational settings. However, in a previous study, we found that discourse goals (persuasion vs. consensus) while arguing can affect student outcomes in both content learning and reasoning. Aims: In this study, we look at argumentative discourse data from a previous study…

Matters of Care in Alberta's "Inspiring Education" Policy: A Critical Feminist Discourse Analysis

ERIC Educational Resources Information Center

Bohachyk, Laura

2016-01-01

Using the ethics of care as a theoretical lens, alongside the techniques of discourse analysis, I critically analyze texts from Alberta's Inspiring Education policies. On the basis of this analysis, I identify two discourses: the sentimental treatment of care and the "facilitator discourse." I argue that a caring teacher-student…

"This Group of Difficult Kids": The Discourse Preservice English Teachers Use to Label Students

ERIC Educational Resources Information Center

Salerno, April S.; Kibler, Amanda K.

2016-01-01

This study attempts to understand how "achievement gap Discourse" might be present in preservice teachers' (PSTs) Discourse about students they found challenging to teach. Using a Discourse analytic approach, the project considers: How do PSTs describe challenging students in their written reflections? Do PSTs draw on students' multiple…

Analyzing the Cohesion of English Text and Discourse with Automated Computer Tools

ERIC Educational Resources Information Center

Jeon, Moongee

2014-01-01

This article investigates the lexical and discourse features of English text and discourse with automated computer technologies. Specifically, this article examines the cohesion of English text and discourse with automated computer tools, Coh-Metrix and TEES. Coh-Metrix is a text analysis computer tool that can analyze English text and discourse…

Promising Ideas for Collective Advancement of Communal Knowledge Using Temporal Analytics and Cluster Analysis

ERIC Educational Resources Information Center

Lee, Alwyn Vwen Yen; Tan, Seng Chee

2017-01-01

Understanding ideas in a discourse is challenging, especially in textual discourse analysis. We propose using temporal analytics with unsupervised machine learning techniques to investigate promising ideas for the collective advancement of communal knowledge in an online knowledge building discourse. A discourse unit network was constructed and…

"You Are Confusing!": Tensions between Teacher's and Students' Discourses in the Classroom

ERIC Educational Resources Information Center

Park, Hyu-Yong

2008-01-01

This article concludes that a "pedagogic discourse" is legitimized in school practices when power in society is actualized and exercised through the use of language as symbolic power. Under these circumstances, the classroom becomes an arena where teachers' discourse as "the regulator" collides with students' discourse as "the regulated".…

Test-Retest Stability of Word Retrieval in Aphasic Discourse

ERIC Educational Resources Information Center

Boyle, Mary

2014-01-01

Purpose: This study examined the test-retest stability of select word-retrieval measures in the discourses of people with aphasia who completed a 5-stimulus discourse task. Method: Discourse samples across 3 sessions from 12 individuals with aphasia were analyzed for the stability of measures of informativeness, efficiency, main concepts, noun and…

Dialogic Discourse in the Classroom

ERIC Educational Resources Information Center

Saglam, Yilmaz; Kanadli, Sedat; Karatepe, Vildan; Gizlenci, Emine Aynur; Goksu, Pinar

2015-01-01

The study aimed to explore the impact of an SDM-based professional development program on teacher discourse. Two types of discourse, authoritative and dialogic discourses, was the focus of the search. From a Bakhtinian standpoint, authoritative words are viewed as located in a distanced zone, do not reflect any individual point of view, and are…

Media Education: The Limits of a Discourse.

ERIC Educational Resources Information Center

Buckingham, David

What is the value and what are the consequences of students gaining access to "critical" academic discourses about the media? Ideally, the acquisition of an academic discourse should make it possible for students to reflect on their own experience in a systematic and rigorous way. Nevertheless, a critical discourse about the media may…

Getting behind Discourses of Love, Care and Maternalism in Early Childhood Education

ERIC Educational Resources Information Center

Aslanian, Teresa K.

2015-01-01

Discourses of love, care and maternalism affect the everyday lives of children enrolled in early childhood education. These discourses bear witness to the ontological transformation that has occurred since the Romantic era that birthed the kindergarten movement to today. Reflecting on historical discourses of love, care and maternalism from the…

Prosody and Functions of Discourse Markers in Mandarin Chinese Conversation: The Cases of "Ranhou," "Wo Juede," and "Meiyou"

ERIC Educational Resources Information Center

Wang, Wei

2017-01-01

This study investigates Mandarin discourse markers from both functional and prosodic perspectives. Discourse markers are defined as sequentially dependent elements which bracket units of talk (Schiffrin 1987). In this study, I focus on three discourse markers, "ranhou" "then", "wo juede" "I think/feel", and…

Religion in the National Historical Narrative of the Early Modern Times in Contemporary Ukrainian Schooling

ERIC Educational Resources Information Center

Shevchenko, Tetiana

2015-01-01

This article deals with religious discourse in modern history school textbooks in Ukraine that cover early modern times in Ukrainian history. It analyzes the place of religious discourse within national discourse, the correlation between local Ukrainian religious and more general discourse, and the representation of the relationships between…

Extended Discourse in First and Second Language Acquisition: A Challenge and an Opportunity

ERIC Educational Resources Information Center

Snow, Catherine E.

2014-01-01

First language learners acquire vocabulary in the context of participation in discourse, and the quantity and richness of that discourse is the best predictor of their progress. Similarly, we argue, engagement in discourse, in particular debate and discussion, is an effective component of classroom instruction for second and foreign language…

Narrative and the Origins of Discourse: Patterns of Discourse in Stories around the World

ERIC Educational Resources Information Center

Rose, David

2005-01-01

This paper summarises findings of discourse analyses of traditional stories from eleven language phyla around the world. The aim is a preliminary exploration of relationships amongst diverse languages in patterns of discourse, using a systemic functional language model. Several techniques were developed for managing and displaying the analyses,…

Critical Discourse Analysis and Science Education Texts: Employing Foucauldian Notions of Discourse and Subjectivity

ERIC Educational Resources Information Center

Bazzul, Jesse

2014-01-01

This article supports critical, social justice oriented science education research by providing a theoretical and methodological basis for examining how subjectivities may be constituted through discourses found in science education texts. Such research explores how discourses orient teachers and students to the world, others, and themselves, as…

The Construction of Cultural Values and Beliefs in Chinese Language Textbooks: A Critical Discourse Analysis

ERIC Educational Resources Information Center

Liu, Yongbing

2005-01-01

This article examines the discourses of cultural values and beliefs constructed in Chinese language textbooks currently used for primary school students nationwide in China. By applying story grammar analysis in the framework of critical discourse analysis, the article critically investigates how the discourses are constructed and what ideological…

Critical Instance Analysis of News English Discourse

ERIC Educational Resources Information Center

Pang, Hongmei; Wu, Sijun

2009-01-01

Critical discourse analysis (CDA) thought that the discourse was concrete social practice, and the language served for the potency, and the discourse embodied the ideology. Two presses about the case that the US Mattel Toy Company recalled toys "Made in China" in Washington Post (newspaper) and New York Times (newspaper) were taken as…

A Discourse Based Approach to the Language Documentation of Local Ecological Knowledge

ERIC Educational Resources Information Center

Odango, Emerson Lopez

2016-01-01

This paper proposes a discourse-based approach to the language documentation of local ecological knowledge (LEK). The knowledge, skills, beliefs, cultural worldviews, and ideologies that shape the way a community interacts with its environment can be examined through the discourse in which LEK emerges. 'Discourse-based' refers to two components:…

Constructing Childhood: Discourses about School Violence in the Greek Daily Press

ERIC Educational Resources Information Center

Avgitidou, Sofia; Stamou, Anastasia G.

2013-01-01

This study explores the construction of discourses about childhood in the Greek daily press. It employs the theoretical frameworks of the new sociology of childhood and critical discourse analysis to question which discourses of childhood are constructed in the daily press presenting cases where children were the victimisers in school violent…

Teacher Response to Discourse in Inclusion Settings: Challenges within Professional Contexts

ERIC Educational Resources Information Center

Bechtold, Ginger Kellett

2011-01-01

Classroom teachers draw upon a variety of discourses to understand and make decisions about the students they teach. This case study investigation explored the discourses at work in inclusion classrooms, with particular attention paid to the way in which discourses may impact the problem of overrepresentation in special education. Frameworks that…

Scarcity discourses and their impacts on renal care policy, practices, and everyday experiences in rural British Columbia

PubMed Central

Brassolotto, Julia; Daly, Tamara

2017-01-01

Drawing from a qualitative case study in rural British Columbia, Canada, this paper examines the discourse of kidney scarcity and its impact on renal care policies and practices. Our findings suggest that at different levels of care, there are different discourses and treatment foci. We have identified three distinct scarcity discourses at work. At the macro policy level, the scarcity of transplantable kidneys is the dominant discourse. At the meso health care institution level, we witnessed a discourse regarding the scarcity of health care and human resources. At the micro community level, there was a discourse of the scarcity of health and life-sustaining resources. For each form of scarcity, particular responses are encouraged. At the macro level, renal care and transplant organizations emphasize the benefits of kidney transplantation and procuring more donors. At the meso level, participants from the regional health care system increasingly encourage home hemodialysis and patient-led care. At the micro level, community health care professionals push for rural renal patients to attend dialysis and maintain their care plans. This work contributes to critical, interdisciplinary organ transfer discourse by contextualizing kidney scarcity. It reveals the tension between these discourses and the implications of pursuing kidney donations without addressing the conditions in which individuals experience kidney failure. PMID:26854624

Exploring the Dominant Discourse of Baccalaureate Nursing Education in Iran

PubMed Central

Yazdannik, Ahmadreza; Yousefy, Alireza; Mohammadi, Sepideh

2017-01-01

Introduction: Understanding how academic dominant discourse is implicated in the shaping of nursing identity, professional aspirations and socialization of nursing students is useful as it can lead to strategies that promote nursing profession. Materials and Methods: This is a qualitative research conducted through discourse analysis approach. Semi-structured interviews, focus group, and direct observation of undergraduate theoretical and clinical courses were used to collect the data. Participants were 71 nursing students, 20 nursing educators, and 5 nursing board staffs from five universities in Iran. Results: Data analysis resulted in the development of four main themes that represent essential discourses of nursing education. The discourses explored are theoretical and scientific nursing, domination of biomedical paradigm, caring as an empty signifier, and more than expected role of research in nursing education discourse. Conclusions: The results indicated that academics attempt to define itself based on “scientific knowledge” and faculties seek to socialize students by emphasizing the scientific/theoretical basis of nursing and research, with the dominance of biomedical discourse. It fails to conceptually grasp the reality of nursing practice, and the result is an untested and impoverished theoretical discourse. The analysis highlights the need for the formation of a strong and new discourse, which contains articulation of signifiers extracted from the nature of the profession. PMID:28382053

Promoting elementary students' epistemology of science through computer-supported knowledge-building discourse and epistemic reflection

NASA Astrophysics Data System (ADS)

Lin, Feng; Chan, Carol K. K.

2018-04-01

This study examined the role of computer-supported knowledge-building discourse and epistemic reflection in promoting elementary-school students' scientific epistemology and science learning. The participants were 39 Grade 5 students who were collectively pursuing ideas and inquiry for knowledge advance using Knowledge Forum (KF) while studying a unit on electricity; they also reflected on the epistemic nature of their discourse. A comparison class of 22 students, taught by the same teacher, studied the same unit using the school's established scientific investigation method. We hypothesised that engaging students in idea-driven and theory-building discourse, as well as scaffolding them to reflect on the epistemic nature of their discourse, would help them understand their own scientific collaborative discourse as a theory-building process, and therefore understand scientific inquiry as an idea-driven and theory-building process. As hypothesised, we found that students engaged in knowledge-building discourse and reflection outperformed comparison students in scientific epistemology and science learning, and that students' understanding of collaborative discourse predicted their post-test scientific epistemology and science learning. To further understand the epistemic change process among knowledge-building students, we analysed their KF discourse to understand whether and how their epistemic practice had changed after epistemic reflection. The implications on ways of promoting epistemic change are discussed.

Beyond homogenization discourse: Reconsidering the cultural consequences of globalized medical education.

PubMed

Gosselin, K; Norris, J L; Ho, M-J

2016-07-01

Global medical education standards, largely designed in the West, have been promoted across national boundaries with limited regard for cultural differences. This review aims to identify discourses on cultural globalization in medical education literature from non-Western countries. To explore the diversity of discourses related to globalization and culture in the field of medical education, the authors conducted a critical review of medical education research from non-Western countries published in Academic Medicine, Medical Education and Medical Teacher from 2006 to 2014. Key discourses about globalization and culture emerged from a preliminary analysis of this body of literature. A secondary analysis identified inductive sub-themes. Homogenization, polarization and hybridization emerged as key themes in the literature. These findings demonstrate the existence of discourses beyond Western-led homogenization and the co-existence of globalization discourses ranging from homogenization to syncretism to resistance. This review calls attention to the existence of manifold discourses about globalization and culture in non-Western medical education contexts. In refocusing global medical education processes to avoid Western cultural imperialism, it will also be necessary to avoid the pitfalls of other globalization discourses. Moving beyond existing discourses, researchers and educators should work towards equitable, context-sensitive and locally-driven approaches to global medical education.

Large-scale changes in network interactions as a physiological signature of spatial neglect

PubMed Central

Baldassarre, Antonello; Ramsey, Lenny; Hacker, Carl L.; Callejas, Alicia; Astafiev, Serguei V.; Metcalf, Nicholas V.; Zinn, Kristi; Rengachary, Jennifer; Snyder, Abraham Z.; Carter, Alex R.; Shulman, Gordon L.

2014-01-01

The relationship between spontaneous brain activity and behaviour following focal injury is not well understood. Here, we report a large-scale study of resting state functional connectivity MRI and spatial neglect following stroke in a large (n = 84) heterogeneous sample of first-ever stroke patients (within 1–2 weeks). Spatial neglect, which is typically more severe after right than left hemisphere injury, includes deficits of spatial attention and motor actions contralateral to the lesion, and low general attention due to impaired vigilance/arousal. Patients underwent structural and resting state functional MRI scans, and spatial neglect was measured using the Posner spatial cueing task, and Mesulam and Behavioural Inattention Test cancellation tests. A principal component analysis of the behavioural tests revealed a main factor accounting for 34% of variance that captured three correlated behavioural deficits: visual neglect of the contralesional visual field, visuomotor neglect of the contralesional field, and low overall performance. In an independent sample (21 healthy subjects), we defined 10 resting state networks consisting of 169 brain regions: visual-fovea and visual-periphery, sensory-motor, auditory, dorsal attention, ventral attention, language, fronto-parietal control, cingulo-opercular control, and default mode. We correlated the neglect factor score with the strength of resting state functional connectivity within and across the 10 resting state networks. All damaged brain voxels were removed from the functional connectivity:behaviour correlational analysis. We found that the correlated behavioural deficits summarized by the factor score were associated with correlated multi-network patterns of abnormal functional connectivity involving large swaths of cortex. Specifically, dorsal attention and sensory-motor networks showed: (i) reduced interhemispheric functional connectivity; (ii) reduced anti-correlation with fronto-parietal and default mode networks in the right hemisphere; and (iii) increased intrahemispheric connectivity with the basal ganglia. These patterns of functional connectivity:behaviour correlations were stronger in patients with right- as compared to left-hemisphere damage and were independent of lesion volume. Our findings identify large-scale changes in resting state network interactions that are a physiological signature of spatial neglect and may relate to its right hemisphere lateralization. PMID:25367028

Neoliberal Common Sense and Race-Neutral Discourses: A Critique of "Evidence-Based" Policy-Making in School Policing

ERIC Educational Resources Information Center

Nolan, Kathleen

2015-01-01

The author of this paper uses critical discourse analysis and draws on critical social theory and policy studies to analyze the interdiscursivity between neoliberal common sense discourses around crime and safety and race-neutral discourses, "evidence-based" policy, and the research that supports school policing programs. The author…

Decentering: A Characteristic of Effective Student-Student Discourse in Inquiry-Oriented Physical Chemistry Classrooms

ERIC Educational Resources Information Center

Moon, Alena; Stanford, Courtney; Cole, Renee; Towns, Marcy

2017-01-01

Recent science reform documents have called for incorporating authentic scientific discourse into science classes as engaging in discourse has shown to result in numerous benefits. Whether these benefits are observed in students depends upon the quality of the discourse in which they engage. However, characterizing the quality of student-student…

From Moves to Sequences: Expanding the Unit of Analysis in the Study of Classroom Discourse

ERIC Educational Resources Information Center

Lefstein, Adam; Snell, Julia; Israeli, Mirit

2015-01-01

What is the appropriate unit of analysis for the study of classroom discourse? One common analytic strategy employs individual discourse moves, which are coded, counted and used as indicators of the quality of classroom talk. In this article we question this practice, arguing that discourse moves are positioned within sequences that critically…

Discourse Markers in College English Listening Instruction: An Empirical Study of Chinese Learners

ERIC Educational Resources Information Center

Zhang, Jianfeng

2012-01-01

Discourse markers can clearly indicate the organization of discourse, remind the hearer of the preceding and the following contents, and express clearly the concrete speech acts. The aims of this study are to explore the relationship between the discourse-marker-based model and listening comprehension as well as the different effects of such a…

Discourse Connectives in L1 and L2 Argumentative Writing

ERIC Educational Resources Information Center

Hu, Chunyu; Li, Yuanyuan

2015-01-01

Discourse connectives (DCs) are multi-functional devices used to connect discourse segments and fulfill interpersonal levels of discourse. This study investigates the use of selected 80 DCs within 11 categories in the argumentative essays produced by L1 and L2 university students. The analysis is based on the International Corpus Network of Asian…

Turning the Lens: Reflexivity in Research & Teaching with Critical Discourse Analysis

ERIC Educational Resources Information Center

Warburton, Trevor

2016-01-01

This article explores the use of Critical Discourse Analysis in truth-telling in education research. I argue that without critical reflexivity Critical Discourse Analysis can become a means of reinforcing and reinscribing some of the same dominant discourses that we critique. Here I suggest the recognition that in the role of teacher and…

National and Post-National Discourses and the Construction of Linguistic Identities by Students of Albanian Origin in Greece

ERIC Educational Resources Information Center

Archakis, Argiris

2016-01-01

Drawing on Critical Discourse Analysis and, more specifically, on the relationship between the macro-level of dominant discourses and the micro-level of individual positionings, we examine the way linguistic identities are constructed by immigrant students of Albanian origin in Greece. We elaborate on two "competitive" discourses: the…

Normative Discourse and Persuasion: An Analysis of Ga'dang Informal Litigation.

ERIC Educational Resources Information Center

Walrod, Michael R.

A study of the discourse of Ga'dang, a Philippine language, focuses on normative discourse and persuasion, especially the ways in which the former is used to accomplish the latter. The first five chapters outline the theoretical framework of the study, placing normative and persuasive discourse in a philosophical context and relating them to the…

[Not] Losing My Religion: Using "The Color Purple" to Promote Critical Thinking in the Writing Classroom

ERIC Educational Resources Information Center

McCrary, Donald

2009-01-01

Private student discourses are often ignored or prohibited in the academy; however, these private discourses are very meaningful, and representative of the ways that students order and speak about the world. Specifically, religion is an extremely significant private student discourse; exploring religious discourse might help students not only to…

The Common Topoi of STEM Discourse: An Apologia and Methodological Proposal, with Pilot Survey

ERIC Educational Resources Information Center

Walsh, Lynda

2010-01-01

In this article, the author proposes a methodology for the rhetorical analysis of scientific, technical, mathematical, and engineering (STEM) discourse based on the common topics (topoi) of this discourse. Beginning with work by Miller, Prelli, and other rhetoricians of STEM discourse--but factoring in related studies in cognitive linguistics--she…

Eyes Wide Shut: The Use and Uselessness of the Discourse of Aesthetics in Art Education

ERIC Educational Resources Information Center

Tavin, Kevin

2007-01-01

The discourse of aesthetics appears repeatedly throughout literature in art education and is employed frequently through K-12 classroom practice. This article discusses the use and uselessness of the discourse of aesthetics in art education. Discourse, as used in this article, refers to the specific term "aesthetics," and all the individual and…

Seeing Possible Futures: Khmer Youth and the Discourse of the American Dream

ERIC Educational Resources Information Center

McGinnis, Theresa A.

2009-01-01

In this article, I add to the critique of the myth of the American Dream by examining ethnographically the ways its dominant discourse is circulated to Khmer American middle school children of migratory agricultural workers. Drawing on social theories of discourse, I juxtapose the ideology embedded in the American Dream Discourse with the…

Girls' Bodily Activities in Physical Education How Current Fitness and Sport Discourses Influence Girls' Identity Construction

ERIC Educational Resources Information Center

Walseth, Kristin; Aartun, Iselin; Engelsrud, Gunn

2017-01-01

Girls' identity constructions are influenced by the dominant sport, health and beauty discourses in their society. Recent research indicates that sport and health discourses embedded in physical education (PE) compete for influence. Some of these studies have illustrated how these discourses inform girls' social construction of body ideals and…

Discourse, Complexity, Normativity: Tracing the Elaboration of Foucault's Materialist Concept of Discourse

ERIC Educational Resources Information Center

Olssen, Mark

2014-01-01

In this article, I want to suggest that it is through the elaboration of the concept of discourse that the differences between Foucault and thinkers like Habermas, Hegel and Marx can best be understood. Foucault progressively develops a conception of discourse as a purely historical category that resists all reference to transcendental principles…

Mixed Messages: Discourses of Education in Policy Speeches to the Japanese Diet

ERIC Educational Resources Information Center

Rear, David

2011-01-01

This paper will examine how Japanese education policy was articulated discursively from 1996 to 2010 in the semi-annual speeches of prime ministers to the Diet. It will identify three distinct discourses within these policy statements: a progressive discourse emphasizing the rights of individuals; a neo-liberal discourse of social independence and…

Troubling the Discourse of Teacher Centrality: A Comparative Perspective

ERIC Educational Resources Information Center

Larsen, Marianne A.

2010-01-01

The belief in the central role of the teacher has a long and comparative history. This article aims to critically analyse the discourse of the centrality of the teacher by both historicising and problematising the ideas and practices associated with this discourse. First, the article describes the discourse as it was taken up during the…

Analyzing Discourse: Text and Talk. Georgetown University Round Table on Languages and Linguistics (Washington, D.C., 1981).

ERIC Educational Resources Information Center

Tannen, Deborah, Ed.

The Georgetown Round Table on discourse analysis dealt with the following aspects of the topic: Emerson's essay on language; oral remembering and narrative structures; persuasive discourse; social construction of topical cohesion; discourse as an interactional achievement; the place of intonation; topic as the unit of analysis in a criminal law…

Tensions between Discourses of Development, Religion, and Human Capital in Early Childhood Education Policy Texts: The Case of Indonesia

ERIC Educational Resources Information Center

Formen, Ali; Nuttall, Joce

2014-01-01

In this paper we consider how particular discourses have come to dominate early childhood education (ECE) policy in Indonesia. We briefly explain the governance of Indonesian ECE and then our approach to policy analysis using critical discourse analysis. Three prevalent discourses are identified and discussed: "developmentalism",…

Distal airways in humans: dynamic hyperpolarized 3He MR imaging--feasibility

NASA Technical Reports Server (NTRS)

Tooker, Angela C.; Hong, Kwan Soo; McKinstry, Erin L.; Costello, Philip; Jolesz, Ferenc A.; Albert, Mitchell S.

2003-01-01

Dynamic hyperpolarized helium 3 (3He) magnetic resonance (MR) imaging of the human airways is achieved by using a fast gradient-echo pulse sequence during inhalation. The resulting dynamic images show differential contrast enhancement of both distal airways and the lung periphery, unlike static hyperpolarized 3He MR images on which only the lung periphery is seen. With this technique, up to seventh-generation airway branching can be visualized. Copyright RSNA, 2003.

Non-oxidized porous silicon-based power AC switch peripheries.

PubMed

Menard, Samuel; Fèvre, Angélique; Valente, Damien; Billoué, Jérôme; Gautier, Gaël

2012-10-11

We present in this paper a novel application of porous silicon (PS) for low-power alternating current (AC) switches such as triode alternating current devices (TRIACs) frequently used to control small appliances (fridge, vacuum cleaner, washing machine, coffee makers, etc.). More precisely, it seems possible to benefit from the PS electrical insulation properties to ensure the OFF state of the device. Based on the technological aspects of the most commonly used AC switch peripheries physically responsible of the TRIAC blocking performances (leakage current and breakdown voltage), we suggest to isolate upper and lower junctions through the addition of a PS layer anodically etched from existing AC switch diffusion profiles. Then, we comment the voltage capability of practical samples emanating from the proposed architecture. Thanks to the characterization results of simple Al-PS-Si(P) structures, the experimental observations are interpreted, thus opening new outlooks in the field of AC switch peripheries.

MEMS Direct Chip Attach Packaging Methodologies and Apparatuses for Harsh Environments

NASA Technical Reports Server (NTRS)

Okojie, Robert S. (Inventor)

2009-01-01

Methods of bulk manufacturing high temperature sensor subassembly packages are disclosed and claimed. Sensors are sandwiched between a top cover and a bottom cover so as to enable the peripheries of the top covers, sensors and bottom covers to be sealed and bound securely together are disclosed and claimed. Sensors are placed on the bottom covers leaving the periphery of the bottom cover exposed. Likewise, top covers are placed on the sensors leaving the periphery of the sensor exposed. Individual sensor sub-assemblies are inserted into final packaging elements which are also disclosed and claimed. Methods of directly attaching wires or pins to contact pads on the sensors are disclosed and claimed. Sensors, such as pressure sensors and accelerometers, and headers made out of silicon carbide and aluminum nitride are disclosed and claimed. Reference cavities are formed in some embodiments disclosed and claimed herein where top covers are not employed.

MEMS Direct Chip Attach Packaging Methodologies and Apparatuses for Harsh Environments

NASA Technical Reports Server (NTRS)

Okojie, Robert S. (Inventor)

2005-01-01

Methods of bulk manufacturing high temperature sensor sub-assembly packages are disclosed and claimed. Sensors are sandwiched between a top cover and a bottom cover so as to enable the peripheries of the top covers, sensors and bottom covers to be sealed and bound securely together are disclosed and claimed. Sensors are placed on the bottom covers leaving the periphery of the bottom cover exposed. Likewise, top covers are placed on the sensors leaving the periphery of the sensor exposed. Individual sensor sub- assemblies are inserted into final packaging elements which are also disclosed and claimed. Methods of directly attach- ing wires or pins to contact pads on the sensors are disclosed and claimed. Sensors, such as pressure sensors and accelerometers, and headers made out of silicon carbide and aluminum nitride are disclosed and claimed. Reference cavities are formed in some embodiments disclosed and claimed herein where top covers are not employed.

Kindergarten students' explanations during science learning

NASA Astrophysics Data System (ADS)

Harris, Karleah

The study examines kindergarten students' explanations during science learning. The data on children's explanations are drawn from videotaped and transcribed discourse collected from four public kindergarten science classrooms engaged in a life science inquiry unit on the life cycle of the monarch butterfly. The inquiry unit was implemented as part of a larger intervention conducted as part of the Scientific Literacy Project or SLP (Mantzicopoulos, Patrick & Samarapungavan, 2005). The children's explanation data were coded and analyzed using quantitative content analysis procedures. The coding procedures involved initial "top down" explanation categories derived from the existing theoretical and empirical literature on scientific explanation and the nature of students' explanations, followed by an inductive or "bottom up" analysis, that evaluated and refined the categorization scheme as needed. The analyses provide important descriptive data on the nature and frequency of children's explanations generated in classroom discourse during the inquiry unit. The study also examines how teacher discourse strategies during classroom science discourse are related to children's explanations. Teacher discourse strategies were coded and analyzed following the same procedures as the children's explanations as noted above. The results suggest that, a) kindergarten students have the capability of generating a variety of explanations during inquiry-based science learning; b) teachers use a variety of classroom discourse strategies to support children's explanations during inquiry-based science learning; and c) The conceptual discourse (e.g., asking for or modeling explanations, asking for clarifications) to non-conceptual discourse (e.g., classroom management discourse) is related to the ratio of explanatory to non-explanatory discourse produced by children during inquiry-based science learning.

Water quality modeling in the dead end sections of drinking water distribution networks.

PubMed

Abokifa, Ahmed A; Yang, Y Jeffrey; Lo, Cynthia S; Biswas, Pratim

2016-02-01

Dead-end sections of drinking water distribution networks are known to be problematic zones in terms of water quality degradation. Extended residence time due to water stagnation leads to rapid reduction of disinfectant residuals allowing the regrowth of microbial pathogens. Water quality models developed so far apply spatial aggregation and temporal averaging techniques for hydraulic parameters by assigning hourly averaged water demands to the main nodes of the network. Although this practice has generally resulted in minimal loss of accuracy for the predicted disinfectant concentrations in main water transmission lines, this is not the case for the peripheries of the distribution network. This study proposes a new approach for simulating disinfectant residuals in dead end pipes while accounting for both spatial and temporal variability in hydraulic and transport parameters. A stochastic demand generator was developed to represent residential water pulses based on a non-homogenous Poisson process. Dispersive solute transport was considered using highly dynamic dispersion rates. A genetic algorithm was used to calibrate the axial hydraulic profile of the dead-end pipe based on the different demand shares of the withdrawal nodes. A parametric sensitivity analysis was done to assess the model performance under variation of different simulation parameters. A group of Monte-Carlo ensembles was carried out to investigate the influence of spatial and temporal variations in flow demands on the simulation accuracy. A set of three correction factors were analytically derived to adjust residence time, dispersion rate and wall demand to overcome simulation error caused by spatial aggregation approximation. The current model results show better agreement with field-measured concentrations of conservative fluoride tracer and free chlorine disinfectant than the simulations of recent advection dispersion reaction models published in the literature. Accuracy of the simulated concentration profiles showed significant dependence on the spatial distribution of the flow demands compared to temporal variation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spatial Accessibility to Health Care Services: Identifying under-Serviced Neighbourhoods in Canadian Urban Areas.

PubMed

Shah, Tayyab Ikram; Bell, Scott; Wilson, Kathi

2016-01-01

Urban environments can influence many aspects of health and well-being and access to health care is one of them. Access to primary health care (PHC) in urban settings is a pressing research and policy issue in Canada. Most research on access to healthcare is focused on national and provincial levels in Canada; there is a need to advance current understanding to local scales such as neighbourhoods. This study examines spatial accessibility to family physicians using the Three-Step Floating Catchment Area (3SFCA) method to identify neighbourhoods with poor geographical access to PHC services and their spatial patterning across 14 Canadian urban settings. An index of spatial access to PHC services, representing an accessibility score (physicians-per-1000 population), was calculated for neighborhoods using a 3km road network distance. Information about primary health care providers (this definition does not include mobile services such as health buses or nurse practitioners or less distributed services such as emergency rooms) used in this research was gathered from publicly available and routinely updated sources (i.e. provincial colleges of physicians and surgeons). An integrated geocoding approach was used to establish PHC locations. The results found that the three methods, Simple Ratio, Neighbourhood Simple Ratio, and 3SFCA that produce City level access scores are positively correlated with each other. Comparative analyses were performed both within and across urban settings to examine disparities in distributions of PHC services. It is found that neighbourhoods with poor accessibility scores in the main urban settings across Canada have further disadvantages in relation to population high health care needs. The results of this study show substantial variations in geographical accessibility to PHC services both within and among urban areas. This research enhances our understanding of spatial accessibility to health care services at the neighbourhood level. In particular, the results show that the low access neighbourhoods tend to be clustered in the neighbourhoods at the urban periphery and immediately surrounding the downtown area.

Deletion of flbA results in increased secretome complexity and reduced secretion heterogeneity in colonies of Aspergillus niger.

PubMed

Krijgsheld, Pauline; Nitsche, Benjamin M; Post, Harm; Levin, Ana M; Müller, Wally H; Heck, Albert J R; Ram, Arthur F J; Altelaar, A F Maarten; Wösten, Han A B

2013-04-05

Aspergillus niger is a cell factory for the production of enzymes. This fungus secretes proteins in the central part and at the periphery of the colony. The sporulating zone of the colony overlapped with the nonsecreting subperipheral zone, indicating that sporulation inhibits protein secretion. Indeed, strain ΔflbA that is affected early in the sporulation program secreted proteins throughout the colony. In contrast, the ΔbrlA strain that initiates but not completes sporulation did not show altered spatial secretion. The secretome of 5 concentric zones of xylose-grown ΔflbA colonies was assessed by quantitative proteomics. In total 138 proteins with a signal sequence for secretion were identified in the medium of ΔflbA colonies. Of these, 18 proteins had never been reported to be part of the secretome of A. niger, while 101 proteins had previously not been identified in the culture medium of xylose-grown wild type colonies. Taken together, inactivation of flbA results in spatial changes in secretion and in a more complex secretome. The latter may be explained by the fact that strain ΔflbA has a thinner cell wall compared to the wild type, enabling efficient release of proteins. These results are of interest to improve A. niger as a cell factory.

Spatially resolving the secretome within the mycelium of the cell factory Aspergillus niger.

PubMed

Krijgsheld, Pauline; Altelaar, A F Maarten; Post, Harm; Ringrose, Jeffrey H; Müller, Wally H; Heck, Albert J R; Wösten, Han A B

2012-05-04

Aspergillus niger is an important cell factory for the industrial production of enzymes. These enzymes are released into the culture medium, from which they can be easily isolated. Here, we determined with stable isotope dimethyl labeling the secretome of five concentric zones of 7-day-old xylose-grown colonies of A. niger that had either or not been treated with cycloheximide. As expected, cycloheximide blocked secretion of proteins at the periphery of the colony. Unexpectedly, protein release was increased by cycloheximide in the intermediate and central zones of the mycelium when compared to nontreated colonies. Electron microscopy indicated that this is due to partial degradation of the cell wall. In total, 124 proteins were identified in cycloheximide-treated colonies, of which 19 secreted proteins had not been identified before. Within the pool of 124 proteins, 53 secreted proteins were absent in nontreated colonies, and additionally, 35 proteins were released ≥4-fold in the central and subperipheral zones of cycloheximide-treated colonies when compared to nontreated colonies. The composition of the secretome in each of the five concentric zones differed. This study thus describes spatial release of proteins in A. niger, which is instrumental in understanding how fungi degrade complex substrates in nature.

Evaluating the intensity of fire at the Acheulian site of Gesher Benot Ya'aqov-Spatial and thermoluminescence analyses.

PubMed

Alperson-Afil, Nira; Richter, Daniel; Goren-Inbar, Naama

2017-01-01

This manuscript presents an attempt to evaluate the intensity of fire through spatial patterning and thermoluminescence methodology. Previous studies of Layer II-6 Level 2 at the Acheulian site of Gesher Benot Ya'aqov suggested that hominins differentiated their activities across space, including multiple activities around a hearth reconstructed on the basis of the distribution of burned flint artifacts. A transect of ~4 m was extended from the center of the reconstructed hearth of Level 2 to its periphery in order to examine the intensity of fire. Burned and unburned flint microartifacts were sampled along this transect. The results of earlier and current thermoluminescence (TL) analysis demonstrate a general agreement with the macroscopic determination of burning, indicating that the possibility of misinterpretation based on macroscopic observations is negligible. The TL signal from flint microartifacts close to the hearth's center shows unambiguous signs of strong heating, whereas with increasing distance from the hearth the TL signal can be interpreted as a result of decreasing temperatures and/or shorter durations of exposure to fire in addition to a decreasing number of flints showing fire damage. Our study shows that TL analysis can identify some variation in fire intensity, which allows a more precise classification of burned flint microartifacts with respect to their heating history.

Imaging Cajal’s neuronal avalanche: how wide-field optical imaging of the point-spread advanced the understanding of neocortical structure–function relationship

PubMed Central

Frostig, Ron D.; Chen-Bee, Cynthia H.; Johnson, Brett A.; Jacobs, Nathan S.

2017-01-01

Abstract. This review brings together a collection of studies that specifically use wide-field high-resolution mesoscopic level imaging techniques (intrinsic signal optical imaging; voltage-sensitive dye optical imaging) to image the cortical point spread (PS): the total spread of cortical activation comprising a large neuronal ensemble evoked by spatially restricted (point) stimulation of the sensory periphery (e.g., whisker, pure tone, point visual stimulation). The collective imaging findings, combined with supporting anatomical and electrophysiological findings, revealed some key aspects about the PS including its very large (radius of several mm) and relatively symmetrical spatial extent capable of crossing cytoarchitectural borders and trespassing into other cortical areas; its relationship with underlying evoked subthreshold activity and underlying anatomical system of long-range horizontal projections within gray matter, both also crossing borders; its contextual modulation and plasticity; the ability of its relative spatiotemporal profile to remain invariant to major changes in stimulation parameters; its potential role as a building block for integrative cortical activity; and its ubiquitous presence across various cortical areas and across mammalian species. Together, these findings advance our understanding about the neocortex at the mesoscopic level by underscoring that the cortical PS constitutes a fundamental motif of neocortical structure–function relationship. PMID:28630879

Imaging Cajal's neuronal avalanche: how wide-field optical imaging of the point-spread advanced the understanding of neocortical structure-function relationship.

PubMed

Frostig, Ron D; Chen-Bee, Cynthia H; Johnson, Brett A; Jacobs, Nathan S

2017-07-01

This review brings together a collection of studies that specifically use wide-field high-resolution mesoscopic level imaging techniques (intrinsic signal optical imaging; voltage-sensitive dye optical imaging) to image the cortical point spread (PS): the total spread of cortical activation comprising a large neuronal ensemble evoked by spatially restricted (point) stimulation of the sensory periphery (e.g., whisker, pure tone, point visual stimulation). The collective imaging findings, combined with supporting anatomical and electrophysiological findings, revealed some key aspects about the PS including its very large (radius of several mm) and relatively symmetrical spatial extent capable of crossing cytoarchitectural borders and trespassing into other cortical areas; its relationship with underlying evoked subthreshold activity and underlying anatomical system of long-range horizontal projections within gray matter, both also crossing borders; its contextual modulation and plasticity; the ability of its relative spatiotemporal profile to remain invariant to major changes in stimulation parameters; its potential role as a building block for integrative cortical activity; and its ubiquitous presence across various cortical areas and across mammalian species. Together, these findings advance our understanding about the neocortex at the mesoscopic level by underscoring that the cortical PS constitutes a fundamental motif of neocortical structure-function relationship.

Temporally and Spatially Resolved x-ray Fluorescence Measurements of in-situ Drug Concentration in Metered-Dose Inhaler Sprays

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

Duke, Daniel J.; Kastengren, Alan L.; Mason-Smith, Nicholas

Drug concentration measurements in MDI sprays are typically performed using particle filtration or laser scattering. These techniques are ineffective in proximity to the nozzle, making it difficult to determine how factors such as nozzle design will affect the precipitation of co-solvent droplets in solution-based MDIs, and the final particle distribution. In optical measurements, scattering from the constituents is difficult to separate. We present a novel technique to directly measure drug distribution. A focused x-ray beam was used to stimulate x-ray fluorescence from the bromine in a solution containing 85% HFA, 15% ethanol co-solvent, and 1 / IPBr. Instantaneous concentration measurementsmore » were obtained with 1 ms temporal resolution and 5 spatial resolution, providing information in a region that is inaccessible to many other diagnostics. The drug remains homogeneously mixed over time, but was found to be higher at the centerline than at the periphery. This may have implications for oropharyngeal deposition in vivo. Measurements in the dynamic, turbulent region of MDIs allow us to understand the physical links between formulation, inspiration, and geometry on final particle size and distribution. This will ultimately lead to a better understanding of how MDI design can be improved to enhance respirable fraction.« less

Emerin modulates spatial organization of chromosome territories in cells on softer matrices

PubMed Central

Pradhan, Roopali; Ranade, Devika

2018-01-01

Abstract Cells perceive and relay external mechanical forces into the nucleus through the nuclear envelope. Here we examined the effect of lowering substrate stiffness as a paradigm to address the impact of altered mechanical forces on nuclear structure-function relationships. RNA sequencing of cells on softer matrices revealed significant transcriptional imbalances, predominantly in chromatin associated processes and transcriptional deregulation of human Chromosome 1. Furthermore, 3-Dimensional fluorescence in situ hybridization (3D-FISH) analyses showed a significant mislocalization of Chromosome 1 and 19 Territories (CT) into the nuclear interior, consistent with their transcriptional deregulation. However, CT18 with relatively lower transcriptional dysregulation, also mislocalized into the nuclear interior. Furthermore, nuclear Lamins that regulate chromosome positioning, were mislocalized into the nuclear interior in response to lowered matrix stiffness. Notably, Lamin B2 overexpression retained CT18 near the nuclear periphery in cells on softer matrices. While, cells on softer matrices also activated emerin phosphorylation at a novel Tyr99 residue, the inhibition of which in a phospho-deficient mutant (emerinY99F), selectively retained chromosome 18 and 19 but not chromosome 1 territories at their conserved nuclear locations. Taken together, emerin functions as a key mechanosensor, that modulates the spatial organization of chromosome territories in the interphase nucleus. PMID:29684168

Evolution of pathogen virulence across space during an epidemic

USGS Publications Warehouse

Osnas, Erik; Hurtado, Paul J.; Dobson, Andrew P.

2015-01-01

We explore pathogen virulence evolution during the spatial expansion of an infectious disease epidemic in the presence of a novel host movement trade-off, using a simple, spatially explicit mathematical model. This work is motivated by empirical observations of the Mycoplasma gallisepticum invasion into North American house finch (Haemorhous mexicanus) populations; however, our results likely have important applications to other emerging infectious diseases in mobile hosts. We assume that infection reduces host movement and survival and that across pathogen strains the severity of these reductions increases with pathogen infectiousness. Assuming these trade-offs between pathogen virulence (host mortality), pathogen transmission, and host movement, we find that pathogen virulence levels near the epidemic front (that maximize wave speed) are lower than those that have a short-term growth rate advantage or that ultimately prevail (i.e., are evolutionarily stable) near the epicenter and where infection becomes endemic (i.e., that maximize the pathogen basic reproductive ratio). We predict that, under these trade-offs, less virulent pathogen strains will dominate the periphery of an epidemic and that more virulent strains will increase in frequency after invasion where disease is endemic. These results have important implications for observing and interpreting spatiotemporal epidemic data and may help explain transient virulence dynamics of emerging infectious diseases.

Rejecting Exclusion, Embracing Inclusion: Conversation as Policy-Making at a US Baptist Conference on Sexuality and Covenant

ERIC Educational Resources Information Center

Warner-Garcia, Shawn

2016-01-01

While much of the work on language, policy, and religion has focused on how discourse is influenced by policy, this article presents a case study of how discourse is used to construct policy itself. These policy-making discourses tend to occur in institutional settings; however, non-institutional discourse may also be instrumental in the…

Does the Advanced Proficiency Evaluated in Oral-Like Written Text Support Syntactic Parsing in a Written Academic Text among L2 Japanese Learners?

ERIC Educational Resources Information Center

Kitajima, Ryu

2016-01-01

Corpus linguistics identifies the qualitative difference in the characteristics of spoken discourse vs. written academic discourse. Whereas spoken discourse makes greater use of finite dependent clauses functioning as constituents in other clauses, written academic discourse incorporates noun phrase constituents and complex phrases. This claim can…

Do "Global Citizens" Need the Parochial Cultural Other? Discourse of Immersion in Study Abroad and Learning-by-Doing

ERIC Educational Resources Information Center

Doerr, Neriko Musha

2013-01-01

The discourse of immersion is prevalent but little analysed in the field of study abroad. Linked generally to learning-by-doing, this discourse has significance for "intercultural education". Based on text analyses of three guidebooks on study abroad, this article suggests four effects of the discourse of immersion: It justifies study abroad as…

Contesting Discourses about Physical Education: A Critical Discourse Analysis of 20 Textbooks Used in Physical Education Teacher Education in Denmark

ERIC Educational Resources Information Center

Svendsen, Annemari Munk; Svendsen, Jesper Tinggaard

2017-01-01

This article investigates and problematises how contesting discourses about Physical Education (PE) as a school subject are immersed within textbooks used in Physical Education Teacher Education (PETE) in Denmark. The paper considers PETE textbooks as powerful documents that construct and maintain discourses about PE, and at the same time as…

The Mental Space Function of BUT as a Lexical Discourse Marker in American Sign Language Lectures

ERIC Educational Resources Information Center

Garrow, William George

2012-01-01

This dissertation centers on the application of the mental space theory to expand our understanding of the role lexical discourse markers (LDMs) play in discourse. LDMs have been recognized by many researchers for their discourse connective function(s) (Levinson, 1983; Schiffrin, 1987; Blakemore, 1989, 2000, 2001, 2002; Fraser, 1996, 1999, 2006).…

Generals, Colonels, and Captains: Discourses of Militarism, Education, and Learning in the Canadian University Context

ERIC Educational Resources Information Center

Taber, Nancy

2014-01-01

This article discusses a feminist discourse analysis that explores the ways in which discourses of learning interact with discourses of militarism at four Canadian civilian universities named for military leaders. I discuss how this particular research topic became apparent to me and explore the current national context where it can be argued that…

Resistance to Dialogic Discourse in SSI Teaching: The Effects of an Argumentation-Based Workshop, Teaching Practicum, and Induction on a Preservice Science Teacher

ERIC Educational Resources Information Center

Kilinc, Ahmet; Demiral, Umit; Kartal, Tezcan

2017-01-01

Teaching socioscientific issues (SSI) necessitates dialogic discourse activities. However, a majority of science teachers prefer monologic discourse in SSI contexts. In addition, some of these teachers are resistant to change (from monologic to dialogic discourse) despite certain professional development attempts. The purpose of the present…

Food marketing targeting children: unveiling the ethical perspectives in the discourse on self-regulation.

PubMed

Silva, Dillian Adelaine Cesar da; Cunha, Antonio Carlos Rodrigues da; Cunha, Thiago Rocha da; Rosaneli, Caroline Filla

2017-07-01

When it comes to food marketing, children are one of the major targets. Regulatory actions can play a strategic role in health protection. The objective of this research was to characterize the ethical perspective in the discourse against state regulatory actions on food marketing directed at children, aiming to understand the context of the discourse's production and how it creates meaning. The methodology adopted was qualitative, with documentary analysis and use of concepts and procedures from Discourse Analysis. The work of Hans Jonas, specifically his Responsibility Principle, and Garrafa and Port's Intervention Bioethics oriented the analysis. The self-regulation discourse analysis showed an ethical perspective in which relations of consumption predominate over the children´s vulnerability. The rhetorical excess is constant, as well as the use of resources like naturalization, untruthfulness, ideological dissimulation and euphemism. An erasure of social conflicts takes place, and an ahistorical perspective is present. The discourse does not align with Jonas´ Responsibility Principle, nor those of Intervention Bioethics. Lastly, the ethical perspective of the discourse represents a double paradox, because it is a business discourse that hides its competitive roots and metamorphoses into an ethical one.

Attentive Reading With Constrained Summarization Adapted to Address Written Discourse in People With Mild Aphasia.

PubMed

Obermeyer, Jessica A; Edmonds, Lisa A

2018-03-01

The purpose of this study was to examine the preliminary efficacy of Attentive Reading and Constrained Summarization-Written (ARCS-W) in people with mild aphasia. ARCS-W adapts an existing treatment, ARCS (Rogalski & Edmonds, 2008), to address discourse level writing in mild aphasia. ARCS-W focuses on the cognitive and linguistic skills required for discourse production. This study was a within-subject pre-postdesign. Three people with mild aphasia participated. ARCS-W integrates attentive reading or listening with constrained summarization of discourse level material in spoken and written modalities. Outcomes included macro- (main concepts) and microlinguistic (correct information units, complete utterances) discourse measures, confrontation naming, aphasia severity, and functional communication. All 3 participants demonstrated some generalization to untrained spoken and written discourse at the word, sentence, and text levels. Reduced aphasia severity and/or increased functional communication and confrontation naming were also observed in some participants. The findings of this study provide preliminary evidence of the efficacy of ARCS-W to improve spoken and written discourse in mild aphasia. Different generalization patterns suggest different mechanisms of improvement. Further research and replication are required to better understand how ARCS-W can impact discourse abilities.

Patterns of language and discourse comprehension skills in school-aged children with autism spectrum disorders.

PubMed

Asberg, Jakob

2010-12-01

The present study examined patterns of language and discourse comprehension skills in Swedish school-aged children with autism spectrum disorders (ASD) (n = 16) as compared to a slightly younger group of typically developing children (n = 16) matched for non-verbal cognitive ability. Results suggested significantly lower abilities in narrative discourse comprehension for the ASD group, but not in oral receptive vocabulary or reception of grammar. This difficulty with discourse-level comprehension appeared to be of a general nature, as no evidence was found for the hypothesis that participants with ASD would find comprehension of inferential discourse information disproportionally more difficult than stated information, or for the hypothesis that discourse processing in ASD would be characterized by an elevated processing of explicitly stated narrative details. The study has clinical and educational implications, as the findings suggest that children with ASD would benefit from being offered specific support for discourse-level comprehension. © 2010 The Author. Scandinavian Journal of Psychology © 2010 The Scandinavian Psychological Associations.

Neurobiology in public and private discourse: the case of adults with ADHD.

PubMed

Bröer, Christian; Heerings, Marjolijn

2013-01-01

How do people describe their health? How do their descriptions relate to public definitions? This article focuses on adult attention deficit hyperactivity disorder (ADHD). We look at Dutch adults who adopt the ADHD label and ask: which discourses structure their descriptions of ADHD? How do these relate to the dominant public discourse on ADHD? Do people use, for example, neurobiological explanations of ADHD? The research makes use of Q-methodology, which combines a discursive relational approach with factor analysis. We examine five different personal discourses that partly differ from the public discourse. People borrow neurobiological, psychological, sociological and even holistic arguments from public discourse to come up with a distinct set of discourses. Neurobiology resonates among adults with ADHD but does not dominate their thinking. Contrary to our expectation, this supports reflexivity instead of discipline theory. © 2012 The Authors. Sociology of Health & Illness © 2012 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Assessing the validity of discourse analysis: transdisciplinary convergence

NASA Astrophysics Data System (ADS)

Jaipal-Jamani, Kamini

2014-12-01

Research studies using discourse analysis approaches make claims about phenomena or issues based on interpretation of written or spoken text, which includes images and gestures. How are findings/interpretations from discourse analysis validated? This paper proposes transdisciplinary convergence as a way to validate discourse analysis approaches to research. The argument is made that discourse analysis explicitly grounded in semiotics, systemic functional linguistics, and critical theory, offers a credible research methodology. The underlying assumptions, constructs, and techniques of analysis of these three theoretical disciplines can be drawn on to show convergence of data at multiple levels, validating interpretations from text analysis.

Alise's Small Stories: Indices of Identity Construction and of Resistance to the Discourse of Cognitive Impairment

ERIC Educational Resources Information Center

Lenchuk, Iryna; Swain, Merrill

2010-01-01

In this paper, we discuss two types of discourse: the first one--the discourse of cognitive impairment of a long-term care facility (LTCF) reflected in the institution's language policy and in the language use of several caregivers of the LTCF; and the second one, the discourse of "small" stories (Bamberg and Georgakopoulou 2008) told by Alise, a…

The Right to Development: Construction of a Non-Agriculturalist Discourse of Rurality in Denmark

ERIC Educational Resources Information Center

Svendsen, Gunnar Lind Haase

2004-01-01

The paper argues for the existence of two powerful discourses of rurality in Denmark after World War II. The first one is termed the modernist-agriculturalist discourse. Although still influential in the current public debate, in Denmark as well as in other Western European countries, this discourse of rurality had its heyday in the 1960s. It is…

A qualitative study of discourses on heterosexual anal sexual practice among key, and general populations in Tanzania: implications for HIV prevention.

PubMed

Wamoyi, Joyce; Mongi, Aika; Sally, Mtenga; Kakoko, Deodatus; Shamba, Donat; Geubbels, Eveline; Kapiga, Saidi

2015-04-24

The risk of contracting HIV through heterosexual anal sex (HAS) is significantly higher than from vaginal intercourse. Little has been done to understand the discourses around HAS and terms people use to describe the practice in Tanzania. A better understanding of discourses on HAS would offer useful insights for measurement of the practice as well as designing appropriate interventions to minimise the risks inherent in the practice. This study employed qualitative approaches involving 24 focus group discussions and 81 in-depth interviews. The study was conducted in 4 regions of Tanzania, and included samples from the general population and among key population groups (fishermen, truck drivers, sex workers, food and recreational facilities workers). Discourse analysis was conducted with the aid of NVIVO versions 8 and 10 software. Six discourses were delineated in relation to how people talked about HAS. Secrecy versus openness discourse describes the terms used when talking about HAS. "Other" discourse involved participants' perception of HAS as something practiced by others unrelated to them and outside their communities. Acceptability/trendiness discourse: young women described HAS as something trendy and increasingly gaining acceptability in their communities. Materiality discourse: describes HAS as a practice that was more profitable than vaginal sex. Masculinity discourse involved discussions on men proving their manhood by engaging in HAS especially when women initiated the practice. Masculine attitudes were also reflected in how men described the practice using a language that would be considered crude. Public health discourse: describes HAS as riskier for HIV infection than vaginal sex. The reported use of condoms was low due to the perceptions that condoms were unsuitable for anal sex, but also perceptions among some participants that anal sex was safer than vaginal sex. Discourses among young women and adult men across the study populations were supportive of HAS. These findings provide useful insights in understanding how different population groups talked about HAS and offer a range of terms that interventions and further research on magnitude of HAS could draw on when addressing health risks of HAS among different study populations.

View west within the periphery of the load dispatch model ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View west within the periphery of the load dispatch model board, operator's console is at lower center and button board is at lower right of the photograph; section of model board shown covers substation from Perryman (left) to Frankford (right); instruments at right center of photograph formerly monitored energy usage and were replaced by computerized monitoring system. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Topology-dependent rationality and quantal response equilibria in structured populations

NASA Astrophysics Data System (ADS)

Roman, Sabin; Brede, Markus

2017-05-01

Given that the assumption of perfect rationality is rarely met in the real world, we explore a graded notion of rationality in socioecological systems of networked actors. We parametrize an actors' rationality via their place in a social network and quantify system rationality via the average Jensen-Shannon divergence between the games Nash and logit quantal response equilibria. Previous work has argued that scale-free topologies maximize a system's overall rationality in this setup. Here we show that while, for certain games, it is true that increasing degree heterogeneity of complex networks enhances rationality, rationality-optimal configurations are not scale-free. For the Prisoner's Dilemma and Stag Hunt games, we provide analytic arguments complemented by numerical optimization experiments to demonstrate that core-periphery networks composed of a few dominant hub nodes surrounded by a periphery of very low degree nodes give strikingly smaller overall deviations from rationality than scale-free networks. Similarly, for the Battle of the Sexes and the Matching Pennies games, we find that the optimal network structure is also a core-periphery graph but with a smaller difference in the average degrees of the core and the periphery. These results provide insight on the interplay between the topological structure of socioecological systems and their collective cognitive behavior, with potential applications to understanding wealth inequality and the structural features of the network of global corporate control.

Ultrastructural localization of ChAT-like immunoreactivity in the human vestibular periphery.

PubMed

Kong, W J; Hussl, B; Thumfart, W F; Schrott-Fischer, A

1998-05-01

Acetylcholine (ACh) has long been considered a neurotransmitter candidate in the efferent vestibular system of mammals. Recently, choline acetyltransferase (ChAT), the synthesizing enzyme for ACh, was immunocytochemically localized in all five end-organs of the rat vestibule (Kong et al. (1994) Hear. Res. 75, 192-200). However, there is little information in the literature concerning the cholinergic innervation in the vestibular periphery of man. In the present study the ultrastructural localization of the ChAT-like immunoreactivity in the human vestibular periphery was investigated in order to reveal the cholinergic innervation in the human vestibular end-organs. A modified method of pre-embedding immunoelectron microscopy was applied. It was found that the ChAT-like immunoreactivity was located in the bouton-type vesiculated nerve terminals in the vestibular neurosensory epithelia of man. These ChAT-like immunostained nerve terminals make synaptic contacts either with afferent chalices surrounding type I vestibular sensory hair cells, or with type II vestibular sensory hair cells. These results show that the ChAT-like immunoreactivity in the human vestibular periphery is confined to the efferent vestibular system. The ChAT-containing efferents innervate both type I hair cells and type II hair cells, making postsynaptic and presynaptic contacts, respectively. This study presents evidence that ACh is a neurotransmitter candidate in the efferent vestibular system of man.

Peripheral subnuclear positioning suppresses Tcrb recombination and segregates Tcrb alleles from RAG2

PubMed Central

Chan, Elizabeth A. W.; Teng, Grace; Corbett, Elizabeth; Choudhury, Kingshuk Roy; Bassing, Craig H.; Schatz, David G.; Krangel, Michael S.

2013-01-01

Allelic exclusion requires that the two alleles at antigen-receptor loci attempt to recombine variable (V), diversity (D), and joining (J) gene segments [V(D)J recombination] asynchronously in nuclei of developing lymphocytes. It previously was shown that T-cell receptor β (Tcrb) alleles frequently and stochastically associate with the nuclear lamina and pericentromeric heterochromatin in CD4−CD8− thymocytes. Moreover, rearranged alleles were underrepresented at these locations. Here we used 3D immunofluorescence in situ hybridization to identify recently rearranged Tcrb alleles based on the accumulation of the DNA-repair protein 53BP1. We found that Tcrb alleles recombine asynchronously in double-negative thymocytes and that V(D)J recombination is suppressed on peripheral as compared with central Tcrb alleles. Moreover, the recombination events that did take place at the nuclear periphery preferentially occurred on Tcrb alleles that were partially dissociated from the nuclear lamina. To understand better the mechanism by which V(D)J recombination is suppressed at the nuclear periphery, we evaluated the subnuclear distribution of recombination-activating gene 2 (RAG2) protein. We found that RAG2 abundance was reduced at the nuclear periphery. Moreover, RAG2 was distributed differently from RNA polymerase II and histone H3K4 trimethylation. Our data suggest that the nuclear periphery suppresses V(D)J recombination, at least in part, by segregating Tcrb alleles from RAG proteins. PMID:24218622

Topology-dependent rationality and quantal response equilibria in structured populations.

PubMed

Roman, Sabin; Brede, Markus

2017-05-01

Given that the assumption of perfect rationality is rarely met in the real world, we explore a graded notion of rationality in socioecological systems of networked actors. We parametrize an actors' rationality via their place in a social network and quantify system rationality via the average Jensen-Shannon divergence between the games Nash and logit quantal response equilibria. Previous work has argued that scale-free topologies maximize a system's overall rationality in this setup. Here we show that while, for certain games, it is true that increasing degree heterogeneity of complex networks enhances rationality, rationality-optimal configurations are not scale-free. For the Prisoner's Dilemma and Stag Hunt games, we provide analytic arguments complemented by numerical optimization experiments to demonstrate that core-periphery networks composed of a few dominant hub nodes surrounded by a periphery of very low degree nodes give strikingly smaller overall deviations from rationality than scale-free networks. Similarly, for the Battle of the Sexes and the Matching Pennies games, we find that the optimal network structure is also a core-periphery graph but with a smaller difference in the average degrees of the core and the periphery. These results provide insight on the interplay between the topological structure of socioecological systems and their collective cognitive behavior, with potential applications to understanding wealth inequality and the structural features of the network of global corporate control.

Selection of assessment methods for evaluating banana weevil Cosmopolites sordidus (Coleoptera: Curculionidae) damage on highland cooking banana (Musa spp., genome group AAA-EA).

PubMed

Gold, C S; Ragama, P E; Coe, R; Rukazambuga, N D T M

2005-04-01

Cosmopolites sordidus (Germar) is an important pest on bananas and plantains. Population build-up is slow and damage becomes increasingly important in successive crop cycles (ratoons). Yield loss results from plant loss, mat disappearance and reduced bunch size. Damage assessment requires destructive sampling and is most often done on corms of recently harvested plants. A wide range of damage assessment methods exist and there are no agreed protocols. It is critical to know what types of damage best reflect C. sordidus pest status through their relationships with yield loss. Multiple damage assessment parameters (i.e. for the corm periphery, cortex and central cylinder) were employed in two yield loss trials and a cultivar-screening trial in Uganda. Damage to the central cylinder had a greater effect on plant size and yield loss than damage to the cortex or corm periphery. In some cases, a combined assessment of damage to the central cylinder and cortex showed a better relationship with yield loss than an assessment of the central cylinder alone. Correlation, logistic and linear regression analyses showed weak to modest correlations between damage to the corm periphery and damage to the central cylinder. Thus, damage to the corm periphery is not a strong predictor of the more important damage to the central cylinder. Therefore, C. sordidus damage assessment should target the central cylinder and cortex.

[Pain information pathways from the periphery to the cerebral cortex].

PubMed

Kuroda, Ryotaro; Kawabata, Atsufumi

2003-07-01

A recent PET study revealed that the first and second somatosensory cortices (SI, SII), and the anterior cingulate cortex are activated by painful peripheral stimulation in humans. It has become clear that painful signals (nociceptive information) evoked at the periphery are transmitted via various circuits to the multiple cerebral cortices where pain signals are processed and perceived. Human or clinical pain is not merely a modality of somatic sensation, but associated with the affect that accompanies sensation. Consequently, pain has a somatosensory-discriminative aspect and an affective-cognitive aspect that are processed in different but correlated brain structures in the ascending circuits. Considering the physiologic characteristics and fiber connections, the SI and SII cortices appear to be involved in somatosensory-discriminative pain, and the anterior cingulate cortex (area 24) in the affective-cognitive aspect of pain. This paper deals with the ascending pain pathways from the periphery to these cortices and their interconnections. Our recent findings on the protease-activated receptors 1 and 2 (PAR-1, and -2), which are confirmed to exist in the dorsal root ganglion cells, are also described. Activation of PAR-2 during inflammation or tissue injury at the periphery is pronociceptive, while PAR-1 appears to be antinociceptive. Based on the these findings, PAR-1 and PAR-2 are attracting interest as target molecules for new drug development.

Peripheral subnuclear positioning suppresses Tcrb recombination and segregates Tcrb alleles from RAG2.

PubMed

Chan, Elizabeth A W; Teng, Grace; Corbett, Elizabeth; Choudhury, Kingshuk Roy; Bassing, Craig H; Schatz, David G; Krangel, Michael S

2013-11-26

Allelic exclusion requires that the two alleles at antigen-receptor loci attempt to recombine variable (V), diversity (D), and joining (J) gene segments [V(D)J recombination] asynchronously in nuclei of developing lymphocytes. It previously was shown that T-cell receptor β (Tcrb) alleles frequently and stochastically associate with the nuclear lamina and pericentromeric heterochromatin in CD4(-)CD8(-) thymocytes. Moreover, rearranged alleles were underrepresented at these locations. Here we used 3D immunofluorescence in situ hybridization to identify recently rearranged Tcrb alleles based on the accumulation of the DNA-repair protein 53BP1. We found that Tcrb alleles recombine asynchronously in double-negative thymocytes and that V(D)J recombination is suppressed on peripheral as compared with central Tcrb alleles. Moreover, the recombination events that did take place at the nuclear periphery preferentially occurred on Tcrb alleles that were partially dissociated from the nuclear lamina. To understand better the mechanism by which V(D)J recombination is suppressed at the nuclear periphery, we evaluated the subnuclear distribution of recombination-activating gene 2 (RAG2) protein. We found that RAG2 abundance was reduced at the nuclear periphery. Moreover, RAG2 was distributed differently from RNA polymerase II and histone H3K4 trimethylation. Our data suggest that the nuclear periphery suppresses V(D)J recombination, at least in part, by segregating Tcrb alleles from RAG proteins.

Apocalypticism in Secular Public Discourse: A Proposed Theory.

ERIC Educational Resources Information Center

Mixon, Harold; Hopkins, Mary Frances

1989-01-01

Examines Biblical apocalyptic theory and secular apocalyptic literature. Proposes a new theory of apocalypticism in secular public discourse derived from those two major theories. Provides examples of apocalypticism in secular public discourse. (MM)

Characteristics of Pre-Service Teachers' Online Discourse: The Study of Local Streams

NASA Astrophysics Data System (ADS)

Liang, Ling L.; Ebenezer, Jazlin; Yost, Deborah S.

2010-02-01

This study describes the characteristics of pre-service teachers' discourse on a WebCT Bulletin Board in their investigations of local streams in an integrated mathematics and science course. A qualitative analysis of data revealed that the pre-service teachers conducted collaborative discourse in framing their research questions, conducting research and writing reports. The science teacher educator provided feedback and carefully crafted prompts to help pre-service teachers develop and refine their work. Overall, the online discourse formats enhance out-of-class communication and support collaborative group work. But the discourse on the critical examination of one another's point of views rooted in scientific inquiry appeared to be missing. It is suggested that pre-service teachers should be given more guidance and opportunities in science courses in carrying out scientific discourse that reflects reform-based scientific inquiry.

Pragmatics in discourse performance: insights from aphasiology.

PubMed

Ulatowska, Hanna K; Olness, Gloria Streit

2007-05-01

This article examines the preservation of pragmatic abilities of individuals with aphasia, as manifested in the discourse they produce. The construct of coherence is used as a framework for understanding this pragmatic preservation. Discourse coherence is largely derived from the structure, selection, and highlighting of information expressed in a discourse. Personal narratives, as one type of discourse, represent an extended turn-in-conversation on a topic of personal relevance to the speaker, common in everyday life. As such, they provide a valuable source of information about a speaker's pragmatic ability. Examples of personal narratives told by individuals with aphasia are used to illustrate and discuss the means by which discourse coherence is achieved. These include a tightly structured temporal-causal event line, development of theme, and evaluation of information. Possible approaches to clinical assessment are considered, including use of global rating systems.

From art to applied science.

PubMed

Schatzberg, Eric

2012-09-01

Before "applied science" and "technology" became keywords, the concept of art was central to discourse about material culture and its connections to natural knowledge. By the late nineteenth century, a new discourse of applied science had replaced the older discourse of art. This older discourse of art, especially as presented in Enlightenment encyclopedias, addressed the relationship between art and science in depth. But during the nineteenth century the concept of fine art gradually displaced the broader meanings of "art," thus undermining the utility of the term for discourse on the relationship between knowledge and practice. This narrowed meaning of "art" obscured key aspects of the industrial world. In effect, middle-class agents of industrialism, including "men of science," used the rhetoric of "applied science" and, later, "technology" to cement the exclusion of artisanal knowledge from the discourse of industrial modernity.

[Study on the change of semantic perspective of schistosomiasis control in China].

PubMed

Zhou, Li-ying; Liu, Si-yuan; Li, Yu-ye; Deng, Yao; Yang, Kun

2015-12-01

To analyze the evolution process, discourse and semantic meaning of schistosomiasis prevention and control, so as to provide suggestions for control work. The official documents and mainstream media reports of schistosomiasis prevention and control were selected at different periods as discourse samples, and the deep social reasons behind the strategy change and the semantic meaning of the utterance were analyzed at different periods. The discourse of schistosomiasis prevention and control experienced the evolution of the political discourse, pluralistic discourse and public discourse, and the semantic connotations showed the authority conflict semantic features, and then transferred to semantic cooperation. The prevention and control of schistosomiasis have different semantic meanings at different periods, and the prevention and control work should correspond to a social practice, seek truth from facts, correctly understand the actual situation, and then establish the effective control policy.

Munchausen Syndrome by Proxy/Fabricated and Induced Illness: does the diagnosis serve economic vested interests, rather than the interests of children?

PubMed

Wrennall, Lynne

2007-01-01

The discourse of Munchausen Syndrome by Proxy/Fabricated and Induced Illness posits the widespread incidence of a highly dangerous form of child abuse in which illness and developmental delay in children, is caused by their parents or carers. The discourse has been linked to false allegations of child abuse, hostile adoptions and miscarriages of justice. It has also stimulated concerns that the children's real medical and developmental needs are neglected when their conditions are misdiagnosed as child abuse. This study examines the critical claims that have been levelled against the Munchausen discourse. They provide explanations of the children's problems that compete with the discourse. The claim of the discourse to scientific validity is thereby shown to be questionable. The explanations have been distilled into specific hypotheses, to stimulate further research. The literature from which the hypotheses were derived, identifies problems in the MSbP/FII discourse in five broad areas of science, regarding: the test validity of techniques; construct validity; statistical methods; evidentiary standards and adverse impacts. The main conclusion is that the detailed critical hypotheses, cohere around the central claim that the discourse of Munchausen Syndrome by Proxy/Fabricated and Induced Illness serves economic vested interests, rather than the interests of children. The hypotheses predict adverse health and social outcomes, as a result of the discourse. Consequently, the continued deployment of the discourse would probably be "unsafe and therefore unwise".

The discourse of design-based science classroom activities

NASA Astrophysics Data System (ADS)

Azevedo, Flávio S.; Martalock, Peggy L.; Keser, Tugba

2015-06-01

This paper is an initial contribution to a general theory in which science classroom activity types and epistemological discourse practices are systematically linked. The idea is that activities and discourse are reflexively related, so that different types of science classroom activities (e.g., scientific argumentation, modeling, and design) recruit characteristically distinct forms of participants' (students and teacher) discourse. Such a general theory would eventually map out the full spectrum of discourse practices (and their patterns of manifestation) across various kinds of science classroom activities, and reveal new relationships between forms of both discourse and activities. Because this defines a complex and long-term project, here our aim is simply to delineate this larger theoretical program and to illustrate it with a detailed case study—namely, that of mapping out and characterizing the discourse practices of design- based science classroom activities. To do so, we draw on data from an activity that is prototypically design-based—i.e., one in which students iteratively design and refine an artifact (in this case, pictorial representations of moving objects)—and examine the structure and dynamics of the whole-class discourse practices that emerge around these representational forms. We then compare and contrast these discourse practices to those of an activity that is prototypical of scientific argumentation (taken from the literature)—i.e., one in which students argue between competing theories and explanations of a phenomenon—and begin to illustrate the kinds of insights our theoretical program might afford.

Comparative Critical Discourse Analysis (CDA): Interplay of discourses (D/D1) as third grade urban and suburban science students engage in hypothesis formulation and observation

NASA Astrophysics Data System (ADS)

Mendoza, Carmen Irene Reyes

This qualitative research project is a comparative analysis of Discourses (D/D1) while focused upon the science processes of hypothesis generation and observation in an urban versus suburban elementary science classroom. D designates the instructional and formal academic science Discourse and D1 represents the students' informal, social or home language D1iscourses. In particular, this research study is a critical discourse analysis that examines how the science processes of hypothesis formulation and observation are constituted through the interplay of classroom Discourses (D/D1) as two third grade science teachers teach the same kit-based, inquiry science lessons with their respective urban and suburban students. The research also considers ethnicity, social class, language, and the central role science teachers play mediating between children's everyday world and the world of science. Communicative approach and distinctive patterns of interaction between the European American teachers and their respective students are analyzed through a critical lens to examine underlying issues of equity and power embedded in the instructional Discourse of science. Critical Discourse Analysis (CDA) provides both the theoretical framework and analytical lens. The research informs development of linguistic-based "best" practices to contribute toward promoting greater science teacher awareness in creating linguistic environments that support all students' learning science Discourse and to serve as a springboard for future educational science researchers' use of CDA.

The discourses of incidents: Cougars on Mt. Elden and in Sabino Canyon, Arizona

USGS Publications Warehouse

Mattson, David J.; Clark, Susan G.

2012-01-01

Incidents are relatively short periods of intensified discourse that arise from public responses to symbolically important actions by public officials, and an important part of the conflict that increasingly surrounds state wildlife management in the West. In an effort to better understand incidents as a facet of this conflict, we analyzed the discourses of two incidents in Arizona that were precipitated by the intended removal of cougars by managers in response to public safety concerns. We used newspaper content, 1999–2007, to elucidate seminal patterns of public discourses and discourse coalitions as well as differences in discursive focus between incident periods and background periods. Cougars were mentioned in newspaper articles 13–33 times more often during incidents compared with background periods. State wildlife agency commissioners and hunters were part of a discourse coalition that advocated killing cougars to solve problems, blamed cougars and those who promoted the animals’ intrinsic value and sought to retain power to define and solve cougar-related problems. Personnel from affected state and federal agencies expressed a similar discourse. Environmentalists, animal protection activists, and some elected officials were of a coalition that defined “the problem” primarily in terms of people’s behaviors, including behaviors associated with current institutional arrangements. This discourse advocated decentralizing power over cougar management. The discourses reflected different preferences for the allocations of power and use of lethal versus non-lethal methods, which aligned with apparent core beliefs and participants’ enfranchisement or disenfranchisement by current state-level management power arrangements.

The Legacy of Abstinence-Only Discourses and the Place of Pleasure in US Discourses on Teenage Sexuality

ERIC Educational Resources Information Center

Gresle-Favier, Claire

2010-01-01

This paper aims to examine the potential long-term legacy of abstinence-only discourses in the USA in order to consider the extent of the changes that might actually occur as a consequence of the 2009 presidential election. It first provides a brief overview of the history of discourses regarding youth sexuality and sex education over the past 30…

Punctuation, Prosody, and Discourse: Afterthought Vs. Right Dislocation

PubMed Central

Kalbertodt, Janina; Primus, Beatrice; Schumacher, Petra B.

2015-01-01

In a reading production experiment we investigate the impact of punctuation and discourse structure on the prosodic differentiation of right dislocation (RD) and afterthought (AT). Both discourse structure and punctuation are likely to affect the prosodic marking of these right-peripheral constructions, as certain prosodic markings are appropriate only in certain discourse structures, and punctuation is said to correlate with prosodic phrasing. With RD and AT clearly differing in discourse function (comment-topic structuring vs. disambiguation) and punctuation (comma vs. full stop), critical items in this study were manipulated with regard to the (mis-)match of these parameters. Since RD and AT are said to prosodically differ in pitch range, phrasing, and accentuation patterns, we measured the reduction of pitch range, boundary strength and prominence level. Results show an effect of both punctuation and discourse context (mediated by syntax) on phrasing and accentuation. Interestingly, for pitch range reduction no difference between RDs and ATs could be observed. Our results corroborate a language architecture model in which punctuation, prosody, syntax, and discourse-semantics are independent but interacting domains with correspondence constraints between them. Our findings suggest there are tight correspondence constraints between (i) punctuation (full stop and comma in particular) and syntax, (ii) prosody and syntax as well as (iii) prosody and discourse-semantics. PMID:26648883

Neural mechanisms of discourse comprehension: a human lesion study

PubMed Central

Colom, Roberto; Grafman, Jordan

2014-01-01

Discourse comprehension is a hallmark of human social behaviour and refers to the act of interpreting a written or spoken message by constructing mental representations that integrate incoming language with prior knowledge and experience. Here, we report a human lesion study (n = 145) that investigates the neural mechanisms underlying discourse comprehension (measured by the Discourse Comprehension Test) and systematically examine its relation to a broad range of psychological factors, including psychometric intelligence (measured by the Wechsler Adult Intelligence Scale), emotional intelligence (measured by the Mayer, Salovey, Caruso Emotional Intelligence Test), and personality traits (measured by the Neuroticism-Extraversion-Openness Personality Inventory). Scores obtained from these factors were submitted to voxel-based lesion-symptom mapping to elucidate their neural substrates. Stepwise regression analyses revealed that working memory and extraversion reliably predict individual differences in discourse comprehension: higher working memory scores and lower extraversion levels predict better discourse comprehension performance. Lesion mapping results indicated that these convergent variables depend on a shared network of frontal and parietal regions, including white matter association tracts that bind these areas into a coordinated system. The observed findings motivate an integrative framework for understanding the neural foundations of discourse comprehension, suggesting that core elements of discourse processing emerge from a distributed network of brain regions that support specific competencies for executive and social function. PMID:24293267

Different optical spectral characteristics in a necrotic transmissible venereal tumor and a cystic lesion in the same canine prostate observed by triple-band trans-rectal optical tomography under trans-rectal ultrasound guidance

NASA Astrophysics Data System (ADS)

Jiang, Zhen; Holyoak, G. Reed; Ritchey, Jerry W.; Bartels, Kenneth E.; Rock, Kendra; Ownby, Charlotte L.; Slobodov, Gennady; Bunting, Charles F.; Piao, Daqing

2011-03-01

Different optical spectral characteristics were observed in a necrotic transmissible venereal tumor (TVT) and a cystic lesion in the same canine prostate by triple-wavelength trans-rectal optical tomography under trans-rectal ultrasound (TRUS) guidance. The NIR imager acquiring at 705nm, 785nm and 808nm was used to quantify both the total hemoglobin concentration (HbT) and oxygen saturation (StO2) in the prostate. The TVT tumor in the canine prostate as a model of prostate cancer was induced in a 7-year old, 27 kg dog. A 2 mL suspension of 2.5x106 cells/mL of homogenized TVT cells recovered from an in vivo subcutaneously propagated TVT tumor in an NOD/SCID mouse were injected in the cranial aspect of the right lobe of the canine prostate. The left lobe of the prostate had a cystic lesion present before TVT inoculation. After the TVT homogenate injection, the prostate was monitored weekly over a 9-week period, using trans-rectal NIR and TRUS in grey-scale and Doppler. A TVT mass within the right lobe developed a necrotic center during the later stages of this study, as the mass presented with substantially increased [HbT] in the periphery, with an area of reduced StO2 less than the area of the mass itself shown on ultrasonography. Conversely, the cystic lesion presented with slightly increased [HbT] in the periphery of the lesion shown on ultrasound with oxygen-reduction inside and in the periphery of the lesion. There was no detectable change of blood flow on Doppler US in the periphery of the cystic lesion. The slightly increased [HbT] in the periphery of the cystic lesion was correlated with intra-lesional hemorrhage upon histopathologic examination.

Canada's neglected tropical disease research network: who's in the core-who's on the periphery?

PubMed

Phillips, Kaye; Kohler, Jillian Clare; Pennefather, Peter; Thorsteinsdottir, Halla; Wong, Joseph

2013-01-01

This study designed and applied accessible yet systematic methods to generate baseline information about the patterns and structure of Canada's neglected tropical disease (NTD) research network; a network that, until recently, was formed and functioned on the periphery of strategic Canadian research funding. MULTIPLE METHODS WERE USED TO CONDUCT THIS STUDY, INCLUDING: (1) a systematic bibliometric procedure to capture archival NTD publications and co-authorship data; (2) a country-level "core-periphery" network analysis to measure and map the structure of Canada's NTD co-authorship network including its size, density, cliques, and centralization; and (3) a statistical analysis to test the correlation between the position of countries in Canada's NTD network ("k-core measure") and the quantity and quality of research produced. Over the past sixty years (1950-2010), Canadian researchers have contributed to 1,079 NTD publications, specializing in Leishmania, African sleeping sickness, and leprosy. Of this work, 70% of all first authors and co-authors (n = 4,145) have been Canadian. Since the 1990s, however, a network of international co-authorship activity has been emerging, with representation of researchers from 62 different countries; largely researchers from OECD countries (e.g. United States and United Kingdom) and some non-OECD countries (e.g. Brazil and Iran). Canada has a core-periphery NTD international research structure, with a densely connected group of OECD countries and some African nations, such as Uganda and Kenya. Sitting predominantly on the periphery of this research network is a cluster of 16 non-OECD nations that fall within the lowest GDP percentile of the network. The publication specialties, composition, and position of NTD researchers within Canada's NTD country network provide evidence that while Canadian researchers currently remain the overall gatekeepers of the NTD research they generate; there is opportunity to leverage existing research collaborations and help advance regions and NTD areas that are currently under-developed.

Production of non-canonical sentences in agrammatic aphasia: limits in representation or rule application?

PubMed

Burchert, Frank; Meissner, Nadine; De Bleser, Ria

2008-02-01

The study reported here compares two linguistically informed hypotheses on agrammatic sentence production, the TPH [Friedmann, N., & Grodzinsky, Y. (1997). Tense and agreement in agrammatic production: Pruning the syntactic tree. Brain and Language, 56, 397-425.] and the DOP [Bastiaanse, R., & van Zonneveld, R. (2005). Sentence production with verbs of alternating transitivity in agrammatic Broca's aphasia. Journal of Neurolinguistics, 18, 59-66]. To explain impaired production of non-canonical sentences in agrammatism, the TPH basically relies on deleted or pruned clause structure positions in the left periphery, whereas the DOP appeals to limitations in the application of movement rules. Certain non-canonical sentences such as object-questions and object-relative clauses require the availability of nodes in the left periphery as well as movement to these nodes. In languages with relatively fixed word order such as English, the relevant test cases generally involve a coincidence of left periphery and movement, such that the predictions of the TPH and the DOP are identical although for different reasons. In languages with relatively free word order such as German, on the other hand, it is possible to devise specific tests of the different predictions due to the availability of scrambling. Scrambled object sentences, for example, do not involve the left periphery but do require application of movement in a domain below the left periphery. A study was conducted with German agrammatic subjects which elicited canonical sentences without object movement and non-canonical scrambled sentences with object movement. The results show that agrammatic speakers have a particular problem with the production of scrambled sentences. Further evidence reported in the study from spontaneous speech, elicitation of object relatives, questions and passives and with different agrammatic subjects confirms that non-canonical sentences are generally harder to produce for agrammatics. These findings provide evidence in favor of the DOP and it will be argued that a cross-modal explanation of agrammatic deficits is possible if two factors--movement and canonicity--are taken into consideration.

NUP-1 Is a Large Coiled-Coil Nucleoskeletal Protein in Trypanosomes with Lamin-Like Functions

PubMed Central

DuBois, Kelly N.; Alsford, Sam; Holden, Jennifer M.; Buisson, Johanna; Swiderski, Michal; Bart, Jean-Mathieu; Ratushny, Alexander V.; Wan, Yakun; Bastin, Philippe; Barry, J. David; Navarro, Miguel; Horn, David; Aitchison, John D.; Rout, Michael P.; Field, Mark C.

2012-01-01

A unifying feature of eukaryotic nuclear organization is genome segregation into transcriptionally active euchromatin and transcriptionally repressed heterochromatin. In metazoa, lamin proteins preserve nuclear integrity and higher order heterochromatin organization at the nuclear periphery, but no non-metazoan lamin orthologues have been identified, despite the likely presence of nucleoskeletal elements in many lineages. This suggests a metazoan-specific origin for lamins, and therefore that distinct protein elements must compose the nucleoskeleton in other lineages. The trypanosomatids are highly divergent organisms and possess well-documented but remarkably distinct mechanisms for control of gene expression, including polycistronic transcription and trans-splicing. NUP-1 is a large protein localizing to the nuclear periphery of Trypanosoma brucei and a candidate nucleoskeletal component. We sought to determine if NUP-1 mediates heterochromatin organization and gene regulation at the nuclear periphery by examining the influence of NUP-1 knockdown on morphology, chromatin positioning, and transcription. We demonstrate that NUP-1 is essential and part of a stable network at the inner face of the trypanosome nuclear envelope, since knockdown cells have abnormally shaped nuclei with compromised structural integrity. NUP-1 knockdown also disrupts organization of nuclear pore complexes and chromosomes. Most significantly, we find that NUP-1 is required to maintain the silenced state of developmentally regulated genes at the nuclear periphery; NUP-1 knockdown results in highly specific mis-regulation of telomere-proximal silenced variant surface glycoprotein (VSG) expression sites and procyclin loci, indicating a disruption to normal chromatin organization essential to life-cycle progression. Further, NUP-1 depletion leads to increased VSG switching and therefore appears to have a role in control of antigenic variation. Thus, analogous to vertebrate lamins, NUP-1 is a major component of the nucleoskeleton with key roles in organization of the nuclear periphery, heterochromatin, and epigenetic control of developmentally regulated loci. PMID:22479148

A narrow view: The conceptualization of sexual problems in human sexuality textbooks.

PubMed

Stelzl, Monika; Stairs, Brittany; Anstey, Hannah

2018-02-01

This study examined the ways in which the meaning of 'sexual problems' is constructed and defined in undergraduate human sexuality textbooks. Drawing on feminist and critical discourse frameworks, the dominant as well as the absent/marginalized discourses were identified using critical discourse analysis. Sexual difficulties were largely framed by the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders. Thus, medical discourse was privileged. Alternative conceptualizations and frameworks, such as the New View of Women's Sexual Problems, were included marginally and peripherally. We argue that current constructions of sexuality knowledge reinforce, rather than challenge, existing hegemonic discourses of sexuality.

From sick role to narrative subject: An analytic memoir.

PubMed

Frank, Arthur W

2016-01-01

Questions of illness experience and identity are discussed, based on the analysis of a story told by the breast-cancer activist Audre Lorde. Displacing Parsons' conceptualization of illness as a sick role, I understand the ill person as a narrative subject, defined by discursive possibilities. Three discourses of illness are proposed: the medical institutional discourse, the discourse of illness experience, and the pink-ribbon discourse. Each has its preferred narratives. These discourses overlap and mutually affect each other. Problems with the Foucauldian conceptualization of the subject are considered, and a dialogical imagination of relations of governmentality is proposed. © The Author(s) 2015.

Competing Discourses of Scientific Identity among Postdoctoral Scholars in the Biomedical Sciences.

PubMed

Price, Rebecca M; Kantrowitz-Gordon, Ira; Gordon, Sharona E

2018-06-01

The postdoctoral period is generally one of low pay, long hours, and uncertainty about future career options. To better understand how postdocs conceive of their present and future goals, we asked researchers about their scientific identities while they were in their postdoctoral appointments. We used discourse analysis to analyze interviews with 30 scholars from a research-intensive university or nearby research institutions to better understand how their scientific identities influenced their career goals. We identified two primary discourses: bench scientist and principal investigator (PI). The bench scientist discourse is characterized by implementing other people's scientific visions through work in the laboratory and expertise in experimental design and troubleshooting. The PI discourse is characterized by a focus on formulating scientific visions, obtaining funding, and disseminating results through publishing papers and at invited talks. Because these discourses represent beliefs, they can-and do-limit postdocs' understandings of what career opportunities exist and the transferability of skills to different careers. Understanding the bench scientist and PI discourses, and how they interact, is essential for developing and implementing better professional development programs for postdocs.

[Study on discourse right construction of China's medical aid to Africa].

PubMed

Li-Ying, Zhou; Yao, Deng; Kun, Yang

2016-11-24

To analyze the discourse right construction of China's medical aid to Africa, so as to provide evidences for improving the effect and sustainable development of China's medical aid to Africa. The documents of the discourse right that China constructed in the medical aid to Africa were selected at different periods as discourse samples. The achievement and deficiency were analyzed from four aspects, namely confident, charismatic, influential, and dominant. China's medical team made much in the discourse right construction in their aid to Africa, but some China's medical team members were still too cautious and too low-key. China's medical team gained the trust of the people of Africa, but the language communication difficulties still hampered in China's medical aid to Africa. Chinese medical team were widely praised by the African society, but in the west, some African media, even China's media still neglected to report China's doctors. China's international discourse right were greatly improved, but western countries still dominated the public opinion. China should refer to the actual situation of medical aid to Africa to strengthen the construction of discourse right.

Narrative discourse deficits in amyotrophic lateral sclerosis.

PubMed

Ash, Sharon; Menaged, Anna; Olm, Christopher; McMillan, Corey T; Boller, Ashley; Irwin, David J; McCluskey, Leo; Elman, Lauren; Grossman, Murray

2014-08-05

We examined narrative discourse in amyotrophic lateral sclerosis (ALS) to assess the role of executive functioning in support of language and the neuroanatomical basis for such support. We analyzed a semistructured speech sample in 26 patients with ALS and 19 healthy seniors for narrative discourse features of coherence. Regression analyses related a measure of discourse coherence ("local connectedness") to gray matter atrophy and reduced white matter fractional anisotropy. Patients with ALS were impaired relative to controls on measures of discourse adequacy, including local connectedness and maintenance of the theme. These discourse measures were related to measures of executive functioning but not to motor functioning. Regressions related local connectedness to gray matter atrophy in ventral and dorsal prefrontal regions and to reduced fractional anisotropy in white matter tracts mediating projections between prefrontal regions. Patients with ALS exhibit deficits in their ability to organize narrative discourse. These deficits appear to be related in part to executive limitations. Consistent with the hypothesis that ALS is a multisystem disorder, this deficit is related to disease in prefrontal regions. © 2014 American Academy of Neurology.

Simultaneous dual-color fluorescence microscope: a characterization study.

PubMed

Li, Zheng; Chen, Xiaodong; Ren, Liqiang; Song, Jie; Li, Yuhua; Zheng, Bin; Liu, Hong

2013-01-01

High spatial resolution and geometric accuracy is crucial for chromosomal analysis of clinical cytogenetic applications. High resolution and rapid simultaneous acquisition of multiple fluorescent wavelengths can be achieved by utilizing concurrent imaging with multiple detectors. However, such class of microscopic systems functions differently from traditional fluorescence microscopes. To develop a practical characterization framework to assess and optimize the performance of a high resolution and dual-color fluorescence microscope designed for clinical chromosomal analysis. A dual-band microscopic imaging system utilizes a dichroic mirror, two sets of specially selected optical filters, and two detectors to simultaneously acquire two fluorescent wavelengths. The system's geometric distortion, linearity, the modulation transfer function, and the dual detectors' alignment were characterized. Experiment results show that the geometric distortion at lens periphery is less than 1%. Both fluorescent channels show linear signal responses, but there exists discrepancy between the two due to the detectors' non-uniform response ratio to different wavelengths. In terms of the spatial resolution, the two contrast transfer function curves trend agreeably with the spatial frequency. The alignment measurement allows quantitatively assessing the cameras' alignment. A result image of adjusted alignment is demonstrated to show the reduced discrepancy by using the alignment measurement method. In this paper, we present a system characterization study and its methods for a specially designed imaging system for clinical cytogenetic applications. The presented characterization methods are not only unique to this dual-color imaging system but also applicable to evaluation and optimization of other similar multi-color microscopic image systems for improving their clinical utilities for future cytogenetic applications.

Reduced temporal processing in older, normal-hearing listeners evident from electrophysiological responses to shifts in interaural time difference.

PubMed

Ozmeral, Erol J; Eddins, David A; Eddins, Ann C

2016-12-01

Previous electrophysiological studies of interaural time difference (ITD) processing have demonstrated that ITDs are represented by a nontopographic population rate code. Rather than narrow tuning to ITDs, neural channels have broad tuning to ITDs in either the left or right auditory hemifield, and the relative activity between the channels determines the perceived lateralization of the sound. With advancing age, spatial perception weakens and poor temporal processing contributes to declining spatial acuity. At present, it is unclear whether age-related temporal processing deficits are due to poor inhibitory controls in the auditory system or degraded neural synchrony at the periphery. Cortical processing of spatial cues based on a hemifield code are susceptible to potential age-related physiological changes. We consider two distinct predictions of age-related changes to ITD sensitivity: declines in inhibitory mechanisms would lead to increased excitation and medial shifts to rate-azimuth functions, whereas a general reduction in neural synchrony would lead to reduced excitation and shallower slopes in the rate-azimuth function. The current study tested these possibilities by measuring an evoked response to ITD shifts in a narrow-band noise. Results were more in line with the latter outcome, both from measured latencies and amplitudes of the global field potentials and source-localized waveforms in the left and right auditory cortices. The measured responses for older listeners also tended to have reduced asymmetric distribution of activity in response to ITD shifts, which is consistent with other sensory and cognitive processing models of aging. Copyright © 2016 the American Physiological Society.

Explosively activated egress area

NASA Technical Reports Server (NTRS)

Bement, L. J.; Bailey, J. W. (Inventor)

1983-01-01

A lightweight, add on structure which employs linear shaped pyrotechnic charges to smoothly cut an airframe along an egress area periphery is provided. It compromises reaction surfaces attached to the exterior surface of the airframe's skin and is designed to restrict the skin deflection. That portion of the airframe within the egress area periphery is jettisoned. Retention surfaces and sealing walls are attached to the interior surface of the airframe's skin and are designed to shield the interior of the aircraft during detonation of the pyrotechnic charges.

Advanced Metallic Air Vehicle Structure Program

DTIC Science & Technology

1974-06-01

soapstone line around the periphery of the lower plate from XFO.00 to the outboard edge using edge of MSLO X7224175 as guide. Remove MSLO X7224175. D...hole in the lug reinforcement plates). Make soapstone line to edge of MSLO to denote periphery of cutouts. E. Relocate MSLO X7224175 on opposite end of...of plate). G. Drill .50 diameter holes (10) using the Bux- Magnetic drill unit. See MAP-I-3 for approximate locations of these start and stop holes. A 1

A Critical Discourse Analysis of the New Labour Discourse of Social and Emotional Learning (SEL) across Schools in England and Wales: Conversations with Policymakers

ERIC Educational Resources Information Center

Emery, Carl

2016-01-01

This paper reports on a critical discourse analysis (CDA) of the New Labour (1997-2010) discourse of Social and Emotional Learning (SEL) in schools, and how it was understood and enacted by policymakers in England and in Wales within the context of devolved government across the UK. By SEL I mean universal school-based programs, located in the…

Highlighting hybridity: A critical discourse analysis of teacher talk in science classrooms

NASA Astrophysics Data System (ADS)

Hanrahan, Mary U.

2006-01-01

There is evidence that alienation from science is linked to the dominant discourse practices of science classrooms (cf. Lemke, J. L. (1990). Talking Science: Language, Learning, and Values. Norwood, NJ: Ablex). Yet, in secondary science education it is particularly hard to find evidence of curriculum reform that includes explicit changes in pedagogic discourses to accommodate the needs of students from a wide range of backgrounds. However, such evidence does exist and needs to be highlighted wherever it is found to help address social justice concerns in science education. In this article, I show how critical discourse analysis can be used to explore a way of challenging the dominant discourse in teacher - student interactions in science classrooms. My findings suggest a new way of moving toward more socially just science curricula in middle years and secondary classrooms by using hybrid discourses that can serve emancipatory purposes.

Methodology discourses as boundary work in the construction of engineering education.

PubMed

Beddoes, Kacey

2014-04-01

Engineering education research is a new field that emerged in the social sciences over the past 10 years. This analysis of engineering education research demonstrates that methodology discourses have played a central role in the construction and development of the field of engineering education, and that they have done so primarily through boundary work. This article thus contributes to science and technology studies literature by examining the role of methodology discourses in an emerging social science field. I begin with an overview of engineering education research before situating the case within relevant bodies of literature on methodology discourses and boundary work. I then identify two methodology discourses--rigor and methodological diversity--and discuss how they contribute to the construction and development of engineering education research. The article concludes with a discussion of how the findings relate to prior research on methodology discourses and boundary work and implications for future research.

Navigating contextual constraints in discourse: Design explications in institutional talk

PubMed Central

Herijgers, MLC (Marloes); Maat, HLW (Henk) Pander

2017-01-01

Although institutional discourse is subject to a vast ensemble of constraints, its design is not fixed beforehand. On the contrary, optimizing the satisfaction of these constraints requires considerable discourse design skills from institutional agents. In this article, we analyze how Dutch banks’ mortgage advisors navigate their way through the consultations context. We focus on what we call discourse design explications, that is, stretches of talk in which participants refer to conflicting constraints in the discourse context, at the same time proposing particular discourse designs for dealing with these conflicts. We start by discussing three forms of design explication. Then we will examine the various resolutions they propose for constraint conflicts and show how advisors seek customer consent or cooperation for the proposed designs. Thus our analysis reveals how institutional agents, while providing services, work on demonstrating how the design of these services is optimized and tailored to customers. PMID:28781580

Linguistic analysis of discourse in aphasia: A review of the literature.

PubMed

Bryant, Lucy; Ferguson, Alison; Spencer, Elizabeth

This review examined previous research applications of linguistic discourse analysis to assess the language of adults with aphasia. A comprehensive literature search of seven databases identified 165 studies that applied linguistic measures to samples of discourse collected from people with aphasia. Analysis of methodological applications revealed an increase in published research using linguistic discourse analysis over the past 40 years, particularly to measure the generalisation of therapy outcomes to language in use. Narrative language samples were most frequently subject to analysis though all language genres were observed across included studies. A total of 536 different linguistic measures were applied to examine language behaviours. Growth in the research use of linguistic discourse analysis and suggestions that this growth may be reflected in clinical practice requires further investigation. Future research directions are discussed to investigate clinical use of discourse analysis and examine the differences that exist between research and clinical practice.

The Dominant Obesity Discourse Versus Children's Conceptualizations of Health: A Comparison Through Dialogue and Drawings.

PubMed

Bhagat, Krishna; Howard, Donna E

2018-06-01

The emphasis on childhood obesity reduction has been attributed to the dominant obesity discourse. However, some researchers argue that this discourse may be ineffective and even harmful for children. From a post-structuralist perspective, the dominant obesity discourse has the power to shape children's subjectivities, though subjectivities may also be influenced by personal experiences and other knowledge about bodies and health. There is limited research which explores how children's conceptualizations of health are informed by the dominant obesity discourse. To address this knowledge gap, qualitative data were collected from 8- to 11-year-old children ( n = 29) regarding their conceptualizations of health, healthy bodies, and health practices. Results suggest that children's conceptualizations reflected arguments embedded within the dominant obesity discourse, but at times, also contradicted or deviated from it. Study findings can be applied toward children's health promotion programming to offer a more holistic and inclusive perspective on health and well-being.

Registered Nurses’ Patient Education in Everyday Primary Care Practice

PubMed Central

Bergh, Anne-Louise; Friberg, Febe; Persson, Eva; Dahlborg-Lyckhage, Elisabeth

2015-01-01

Nurses’ patient education is important for building patients’ knowledge, understanding, and preparedness for self-management. The aim of this study was to explore the conditions for nurses’ patient education work by focusing on managers’ discourses about patient education provided by nurses. In 2012, data were derived from three focus group interviews with primary care managers. Critical discourse analysis was used to analyze the transcribed interviews. The discursive practice comprised a discourse order of economic, medical, organizational, and didactic discourses. The economic discourse was the predominant one to which the organization had to adjust. The medical discourse was self-evident and unquestioned. Managers reorganized patient education routines and structures, generally due to economic constraints. Nurses’ pedagogical competence development was unclear, and practice-based experiences of patient education were considered very important, whereas theoretical pedagogical knowledge was considered less important. Managers’ support for nurses’ practical- and theoretical-based pedagogical competence development needs to be strengthened. PMID:28462314

Body talk: students' identity construction while discussing a socioscientific issue

NASA Astrophysics Data System (ADS)

Ideland, Malin; Malmberg, Claes

2012-06-01

Vision II school science is often stated to be a democratic and inclusive form of science education. But what characterizes the subject who fits into the Vision II school science? Who is the desirable student and who is constructed as ill-fitting? This article explores discourses that structure the Vision II science classroom, and how different students construct their identities inside these discourses. In the article we consider school science as an order of discourses which restricts and enables what is possible to think and say and what subject-positions those are available and non-available. The results show that students' talk about a SSI about body and health is constituted by several discourses. We have analyzed how school science discourse, body discourse and general school discourse are structuring the discussions. But these discourses are used in different ways depending on how the students construct their identities in relation to available subject positions, which are dependent on how students at the same time are "doing" gender and social class. As an example, middle class girls show resistance against SSI-work since the practice is threatening their identity as "successful students". This article uses a sociopolitical perspective in its discussions on inclusion and exclusion in the practice of Vision II. It raises critical issues about the inherited complexity of SSI with meetings and/or collisions between discourses. Even if the empirical results from this qualitative study are situated in specific cultural contexts, they contribute with new questions to ask concerning SSI and Vision II school science.

Barrett Wendell's Theory of Discourse.

ERIC Educational Resources Information Center

Newkirk, Thomas

1991-01-01

Discusses Barrett Wendell's theory of discourse, including a critique of his definitions and an assessment of his discourse scheme. Challenges the image of Wendell as a technocrat who never rose above a consideration of style to examine more significant rhetorical issues. (MG)

Taking Science Dialogue by Storm.

ERIC Educational Resources Information Center

Leonard, Jacqueline

2002-01-01

Focuses on how one teacher examined classroom discourse through a unit on tornadoes and natural catastrophes. Defines various types of discourse and discusses how discourse in a 6th grade class was analyzed. Details some of the activities that engaged students. (DDR)

The discourse of causal explanations in school science

NASA Astrophysics Data System (ADS)

Slater, Tammy Jayne Anne

Researchers and educators working from a systemic functional linguistic perspective have provided a body of work on science discourse which offers an excellent starting point for examining the linguistic aspects of the development of causal discourse in school science, discourse which Derewianka (1995) claimed is critical to success in secondary school. No work has yet described the development of causal language by identifying the linguistic features present in oral discourse or by comparing the causal discourse of native and non-native (ESL) speakers of English. The current research responds to this gap by examining the oral discourse collected from ESL and non-ESL students at the primary and high school grades. Specifically, it asks the following questions: (1) How do the teachers and students in these four contexts develop causal explanations and their relevant taxonomies through classroom interactions? (2) What are the causal discourse features being used by the students in these four contexts to construct oral causal explanations? The findings of the social practice analysis showed that the teachers in the four contexts differed in their approaches to teaching, with the primary school mainstream teacher focusing largely on the hands-on practice , the primary school ESL teacher moving from practice to theory, the high school mainstream teacher moving from theory to practice, and the high school ESL teacher relying primarily on theory. The findings from the quantitative, small corpus approach suggest that the developmental path of cause which has been identified in the writing of experts shows up not only in written texts but also in the oral texts which learners construct. Moreover, this move appears when the discourse of high school ESL and non-ESL students is compared, suggesting a developmental progression in the acquisition of these features by these students. The findings also reveal that the knowledge constructed, as shown by the concept maps created from the discourse, follows a developmental path similar to the linguistic causal path, from the concrete, hands-on, observable items to more abstract, theoretical concepts. This study is the first systemic functional comparison of the oral discourse of primary and secondary learners as well as the first to compare ESL and non-ESL speakers in this way, and as such it helps map general trends in causal discourse development. (Abstract shortened by UMI.)

John Adams's Montesquieuean Moment: Enlightened Historicism in the Discourses on Davila.

PubMed

Green, Jonathan

2016-01-01

At the outset of the French Revolution John Adams penned a series of Discourses of Davila, philosophical ruminations on the sixteenth-century French Wars of Religion. Recent historians have read these Discourses in terms of Adams's Machiavellianism-his conviction that men's passions lead to violence, if unrestrained. But this reading overlooks the extent to which Adams intended his Discourses as a particular investigation into the French nation's character, and into whether the revolutionaries could lay claim to a native, French tradition of mixed constitutional government. Situating the Discourses vis-à-vis Adams's contemporaneous reading of Montesquieu, this article argues for an underappreciated historicist dimension to his thought.

The Role and Image of Midwives in Caribbean Society from the Colonial Period to the Present: A Critical Analysis of the Discourse Relevant to Midwifery in Specific Hispanophone, Anglophone, and Francophone Contexts

ERIC Educational Resources Information Center

Crespo-Valedon, Damarys T.

2017-01-01

The dominant discourse on midwifery has been characterized by myths that have been constructed and perpetuated through oral and written discourse. The purpose of this research is to engage in a critical analysis of that discourse, with special focus on Hispanophone, Anglophone, and Francophone contexts in the Caribbean from colonial times to the…

Histopathological Changes in the Periphery of the Sciatic Nerve of Rats after Knee Joint Immobilization

PubMed Central

Yoshida, Shinya; Matsuzaki, Taro; Kamijo, Akio; Araki, Yoshitaka; Sakamoto, Makoto; Moriyama, Shigenori; Hoso, Masahiro

2013-01-01

[Purpose] This study was performed to investigate the histological changes that occur in the periphery of the sciatic nerve in rats undergoing knee immobilization. [Subjects and Methods] 29 male 9-week-old Wistar rats were divided randomly into a control group (C group, n = 7) and an immobilized group (I group, n = 22). The animals in the I group had the left knee joint immobilized in maximal flexion with plaster casts for two weeks. After the experimental period, we obtained cross-sections of tissues from the center of the left thigh, and the periphery of the sciatic nerve was observed under an optical microscope after hematoxylin-eosin staining. [Results] In contrast to the rats of C group, the rats in I group showed adherence between the bundle of nerve fibers and perineurium, as well as thickening of the perineurium. These histological changes were statistically significant. [Conclusions] Immobilization of the knee joints of rats resulted in characteristic histological changes in the connective tissue around the sciatic nerve. PMID:24259816

Internal structure of normal maize starch granules revealed by chemical surface gelatinization.

PubMed

Pan, D D; Jane, J I

2000-01-01

Normal maize starch was fractionated into two sizes: large granules with diameters more than 5 microns and small granules with diameters less than 5 microns. The large granules were surface gelatinized by treating them with an aqueous LiCl solution (13 M) at 22-23 degrees C. Surface-gelatinized remaining granules were obtained by mechanical blending, and gelatinized surface starch was obtained by grinding with a mortar and a pestle. Starches of different granular sizes and radial locations, obtained after different degrees of surface gelatinization, were subjected to scanning electron microscopy, iodine potentiometric titration, gel-permeation chromatography, and amylopectin branch chain length analysis. Results showed that the remaining granules had a rough surface with a lamella structure. Amylose was more concentrated at the periphery than at the core of the granule. Amylopectin had longer long B-chains at the core than at the periphery of the granule. Greater proportions of the long B-chains were present at the core than at the periphery of the granule.

Genome-Nuclear Lamina Interactions Regulate Cardiac Stem Cell Lineage Restriction.

PubMed

Poleshko, Andrey; Shah, Parisha P; Gupta, Mudit; Babu, Apoorva; Morley, Michael P; Manderfield, Lauren J; Ifkovits, Jamie L; Calderon, Damelys; Aghajanian, Haig; Sierra-Pagán, Javier E; Sun, Zheng; Wang, Qiaohong; Li, Li; Dubois, Nicole C; Morrisey, Edward E; Lazar, Mitchell A; Smith, Cheryl L; Epstein, Jonathan A; Jain, Rajan

2017-10-19

Progenitor cells differentiate into specialized cell types through coordinated expression of lineage-specific genes and modification of complex chromatin configurations. We demonstrate that a histone deacetylase (Hdac3) organizes heterochromatin at the nuclear lamina during cardiac progenitor lineage restriction. Specification of cardiomyocytes is associated with reorganization of peripheral heterochromatin, and independent of deacetylase activity, Hdac3 tethers peripheral heterochromatin containing lineage-relevant genes to the nuclear lamina. Deletion of Hdac3 in cardiac progenitor cells releases genomic regions from the nuclear periphery, leading to precocious cardiac gene expression and differentiation into cardiomyocytes; in contrast, restricting Hdac3 to the nuclear periphery rescues myogenesis in progenitors otherwise lacking Hdac3. Our results suggest that availability of genomic regions for activation by lineage-specific factors is regulated in part through dynamic chromatin-nuclear lamina interactions and that competence of a progenitor cell to respond to differentiation signals may depend upon coordinated movement of responding gene loci away from the nuclear periphery. Copyright © 2017 Elsevier Inc. All rights reserved.

Shallow melt apparatus for semicontinuous czochralski crystal growth

DOEpatents

Wang, Tihu; Ciszek, Theodore F.

2006-01-10

In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

Post-ecological discourse in the making.

PubMed

Zeyer, Albert; Roth, Wolff-Michael

2013-01-01

This article analyses the discourse of 15- to16-year-old Swiss junior high school students in order to understand public discourse on the environment and environmental protection. Discourse analysis reveals four interpretive repertoires as the building blocks for the so-called post-ecological discourse, which can be used to describe important aspects of current ways of talking about ecological issues in Europe. We show that 10 theoretically identifiable dimensions of this discourse can be understood in terms of a mutual interplay between the four interpretive repertoires. Post-ecological discourse in today's (Swiss) society appears to be at its core a loss-of-control-discourse, which leads (in our students) to a latent eco-depression. Thus, the public understanding of science can be affected by unintended consequences of the talk itself (in this case an unintended environmental depression), that is, by the inherent characteristics of the involved repertoires, here especially the so-called folk science repertoire. Fostering public understanding of science is thus not merely a question of providing the public with scientific 'facts'. It is also an issue of paying attention to the available discursive repertoires. If necessary, viable alternative repertoires may have to be offered. In school, for example, conversations about the nature of science, and about complexity and applied ethics might help students learn new interpretive repertoires and how to mobilize these in talking about the environment and environmental protection.

Electrophysiological indices of brain activity to content and function words in discourse.

PubMed

Neumann, Yael; Epstein, Baila; Shafer, Valerie L

2016-09-01

An increase in positivity of event-related potentials (ERPs) at the lateral anterior sites has been hypothesized to be an index of semantic and discourse processing, with the right lateral anterior positivity (LAP) showing particular sensitivity to discourse factors. However, the research investigating the LAP is limited; it is unclear whether the effect is driven by word class (function word versus content word) or by a more general process of structure building triggered by elements of a determiner phrase (DP). To examine the neurophysiological indices of semantic/discourse integration using two different word categories (function versus content word) in the discourse contexts and to contrast processing of these word categories in meaningful versus nonsense contexts. Planned comparisons of ERPs time locked to a function word stimulus 'the' and a content word stimulus 'cats' in sentence-initial position were conducted in both discourse and nonsense contexts to examine the time course of processing following these word forms. A repeated-measures analysis of variance (ANOVA) for the Discourse context revealed a significant interaction of condition and site due to greater positivity for 'the' relative to 'cats' at anterior and superior sites. In the Nonsense context, there was a significant interaction of condition, time and site due to greater positivity for 'the' relative to 'cats' at anterior sites from 150 to 350 ms post-stimulus offset and at superior sites from 150 to 200 ms post-stimulus offset. Overall, greater positivity for both 'the' and 'cats' was observed in the discourse relative to the nonsense context beginning approximately 150 ms post-stimulus offset. Additionally, topographical analyses were highly correlated for the two word categories when processing meaningful discourse. This topographical pattern could be characterized as a prominent right LAP. The LAP was attenuated when the target stimulus word initiated a nonsense context. The results of this study support the view that the right LAP is an index of general discourse processing rather than an index of word class. These findings demonstrate that the LAP can be used to study discourse processing in populations with compromised metalinguistic skills, such as adults with aphasia or traumatic brain injury. © 2016 Royal College of Speech and Language Therapists.

Classes of Discourse, Acts of Discourse, Writers, and Readers.

ERIC Educational Resources Information Center

Larson, Richard L.

1992-01-01

Argues that a prevalent mistake made by teachers preparing writing curricula and assignments is dividing writing into classes or modes. Suggests alternatives to classifying writing. Envisions writing as a discourse act and assignments as performance of such acts. (HB)

Short-Term Impact of a Comprehensive Smoke-Free Law Following a Partial Smoke-Free Law on PM2.5 Concentration Levels at Hospitality Venues on the Peripheries of College Campuses

PubMed Central

Yu, Sol; Yang, Wonho; Lee, Kiyoung; Kim, Sungcheon; Ha, Kwonchul; Kim, Sungroul

2015-01-01

Tobacco-free policies on college campuses are spreading in Korea. However, the impact of the smoking ban legislation at venues on the boundary of a college campus is still limited. This study aimed to assess short-term changes in PM2.5 concentrations before and after the enactment of the smoking ban legislation to evaluate the impact. In this cross-sectional study, PM2.5 measurements (pre-ban: n = 99, post-ban: n = 64) were conducted in randomly selected billiards, pubs, and computer game rooms on the peripheries of college campuses in October 2013, prior to implementation of the smoking ban, and in May 2014, after the ban. The median (interquartile range, IQR) of the PM2.5 concentration for all venues was 31 μg/m3 (0–80 μg/m3) in the pre-ban period and 11 μg/m3 (0–36 μg/m3) in the post-ban period implying indoor PM2.5 concentration levels of the peripheries of college campuses likely decreased one year after implementation of the ban. However, the differences were not significant yet. The results support the introduction of more rigorous monitoring of SHS exposure levels toward the ultimate goal of encouraging a complete smoking ban in hospitality venues, including billiards, pubs, and computer game rooms located on the peripheries of college campuses. PMID:26540063

Short-Term Impact of a Comprehensive Smoke-Free Law Following a Partial Smoke-Free Law on PM₂.₅ Concentration Levels at Hospitality Venues on the Peripheries of College Campuses.

PubMed

Yu, Sol; Yang, Wonho; Lee, Kiyoung; Kim, Sungcheon; Ha, Kwonchul; Kim, Sungroul

2015-11-02

Tobacco-free policies on college campuses are spreading in Korea. However, the impact of the smoking ban legislation at venues on the boundary of a college campus is still limited. This study aimed to assess short-term changes in PM2.5 concentrations before and after the enactment of the smoking ban legislation to evaluate the impact. In this cross-sectional study, PM2.5 measurements (pre-ban: n = 99, post-ban: n = 64) were conducted in randomly selected billiards, pubs, and computer game rooms on the peripheries of college campuses in October 2013, prior to implementation of the smoking ban, and in May 2014, after the ban. The median (interquartile range, IQR) of the PM2.5 concentration for all venues was 31 μg/m³ (0-80 μg/m³) in the pre-ban period and 11 μg/m³ (0-36 μg/m³) in the post-ban period implying indoor PM2.5 concentration levels of the peripheries of college campuses likely decreased one year after implementation of the ban. However, the differences were not significant yet. The results support the introduction of more rigorous monitoring of SHS exposure levels toward the ultimate goal of encouraging a complete smoking ban in hospitality venues, including billiards, pubs, and computer game rooms located on the peripheries of college campuses.

Metabolic sensing neurons and the control of energy homeostasis.

PubMed

Levin, Barry E

2006-11-30

The brain and periphery carry on a constant conversation; the periphery informs the brain about its metabolic needs and the brain provides for these needs through its control of somatomotor, autonomic and neurohumoral pathways involved in energy intake, expenditure and storage. Metabolic sensing neurons are the integrators of a variety of metabolic, humoral and neural inputs from the periphery. Such neurons, originally called "glucosensing", also respond to fatty acids, hormones and metabolites from the periphery. They are integrated within neural pathways involved in the regulation of energy homeostasis. Unlike most neurons, they utilize glucose and other metabolites as signaling molecules to regulate their membrane potential and firing rate. For glucosensing neurons, glucokinase acts as the rate-limiting step in glucosensing while the pathways that mediate responses to metabolites like lactate, ketone bodies and fatty acids are less well characterized. Many metabolic sensing neurons also respond to insulin and leptin and other peripheral hormones and receive neural inputs from peripheral organs. Each set of afferent signals arrives with different temporal profiles and by different routes and these inputs are summated at the level of the membrane potential to produce a given neural firing pattern. In some obese individuals, the relative sensitivity of metabolic sensing neurons to various peripheral inputs is genetically reduced. This may provide one mechanism underlying their propensity to become obese when exposed to diets high in fat and caloric density. Thus, metabolic sensing neurons may provide a potential therapeutic target for the treatment of obesity.

The expositive discourse as pedagogical discourse: studying recontextualization in the production of a science museum exhibition

NASA Astrophysics Data System (ADS)

Marandino, Martha

2016-06-01

In this paper I report on the sociological and educational particulars of The Biodiscovery Space exhibition of the Life Museum of the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil, using Basil Bernstein's framework of pedagogic discourse and recontextualization. Data for analysis was obtained from interviews with the exhibition developers, field observations of museum visitors and analysis of exhibition documents. Using the ideas of power, classification and framework, among others, I analyzed the recontextualization process of the production of expositive discourse. Thus, working with Bernstein's idea of classification, I explain the relationship between the discourses of the science of biology, history of science, museology, education, and communication in order to produce an expositive discourse. I also make explicit how agents of the Official Recontextualization Field of the Museum and the Pedagogic Recontextualization Field "....of the Museum determine partly the final expositive discourse of an exhibition". Using the idea of a pedagogic discourse framework, I discuss how the constraints imposed by objects and texts in exhibitions help to create a specific manner of visitor interaction with these elements, "even if they have some autonomy". Considerations about the audience and the intended process of acquisition are presented, when I discuss the control strategies of the exhibition. I propose that the Biodiscovery Space exhibit has a visible pedagogy. Finally, using the collected data I discuss the power tensions created in the production of expositive discourse showing how distributive, recontextualization and evaluation rules work in the context of exhibitions. The study of the dynamics in forming the expositive discourse using Bernstein's framework reveals the individuals and institutions, the selection criteria, the negotiations and the power relations involved. It has the potential to assist both educators and researchers in the museum education field, as well as designers to understand the teaching and learning processes that occur during a visit and to establish relevant criteria to evaluate quality to best produce exhibitions in science museums.

The role of discourse in group knowledge construction: A case study of engineering students

NASA Astrophysics Data System (ADS)

Kittleson, Julie M.; Southerland, Sherry A.

2004-03-01

This qualitative study examined the role of discourse (verbal elements of language) and Discourse (nonverbal elements related to the use of language, such as ways of thinking, valuing, and using tools and technologies) in the process of group knowledge construction of mechanical engineering students. Data included interviews, participant observations, and transcripts from lab sessions of a group of students working on their senior design project. These data were analyzed using discourse analysis focusing on instances of concept negotiation, interaction in which multiple people contribute to the evolving conceptual conversation. In this context, despite instructors' attempts to enhance the collaboration of group members, concept negotiation was rare. In an effort to understand this rarity, we identified themes related to an engineering Discourse, which included participants' assumptions about the purpose of group work, the views about effective groups, and their epistemologies and ontologies. We explore how the themes associated with the engineering Discourse played a role in how and when the group engaged in concept negotiation. We found that underlying ideologies and assumptions related to the engineering Discourse played both facilitating and inhibitory roles related to the group's conceptually based interactions.

Science learning in the context of discourse

NASA Astrophysics Data System (ADS)

do Nascimento, Silvania Sousa

2013-06-01

The original article by Kamberelis and Wehunt (2012) discusses an interesting and important research subject in science education as it focus on classroom interactions and the characteristics of the discourse production of interlocutors. The authors start from the premise that discourse heterogeneity is constitutive of social activities, which is supported by others like Mikhail Bakhtin (Speech genres and other late essays. University of Texas Press, Austin, 1981) and Erving Goffman (Frame analysis: an essay on the organization of experience. Harper and Row, London, 1974). They also present the definitions of three key elements that organize hybrid discourse: (a) lamination of multiple cultural frames, (b) shifting relations between people and their discourse, and (c) shifting power relations between people. Finally, the authors analyze how these three elements organize students' science discourse in the classroom and how it contributes to the creation of a micro-community of practice capable of helping the emergence of a disciplinary knowledge that is legitimized by and strengthens the identity of the group. In the present commentary, I discuss how Michael Foucault's (1970) concept of discursive procedure may help us to analyze the (often neglected) teacher's role in the development of hybrid discourse practices.

Patient or consumer? The colonization of the psychiatric clinic.

PubMed

Evans, Alicia M

2005-12-01

Information is given a privileged place in the psychiatric clinic, as illustrated by the prevalence and volume of data to be collected and forms to be completed by psychiatric nurses. Information though is different to knowledge. The present paper argues that information is part of a managerial discourse that implies commodification whereas knowledge is part of a clinical discourse that allows room for the suffering of the patient. Information belongs to the discourse of managerialism, one that positions the patient as customer/consumer and in doing so renders them unsuffering. The patient's suffering is silenced by their construction as a consumer. The discourse of managerialism seeks a complete data set of information. By way of contrast, another discourse, that of psychoanalysis offers the institution the idea that there are always holes, gaps, and uncertainty. The idea of uncertainty, gaps, things remaining unknown and a limit sits uncomfortably with the dominant discourse of managerialism; one that demands no limits, complete data sets, and many satisfied customers. This market model of managerialism denies the potential of the therapeutic relationship; that something curative might be produced via the transference. In addition, the managerialist discourse potentially positions the patient as both illegitimate and unsuffering.

Traveling Policies: Hijacked in Central Asia

ERIC Educational Resources Information Center

Silova, Iveta

2005-01-01

Since the collapse of the Soviet Union, Central Asian education reform discourses have become increasingly similar to distinctive Western policy discourses traveling globally across national boundaries. Tracing the trajectory of "traveling policies" in Central Asia, this article discusses the way Western education discourses have been…

Talk in Interaction in the Speech-Language Pathology Clinic: Bringing Theory to Practice through Discourse

ERIC Educational Resources Information Center

Leaby, Margaret M.; Walsh, Irene P.

2008-01-01

The importance of learning about and applying clinical discourse analysis to enhance the talk in interaction in the speech-language pathology clinic is discussed. The benefits of analyzing clinical discourse to explicate therapy dynamics are described.

Mapping Mathematics in Classroom Discourse

ERIC Educational Resources Information Center

Herbel-Eisenmann, Beth A.; Otten, Samuel

2011-01-01

This article offers a particular analytic method from systemic functional linguistics, "thematic analysis," which reveals the mathematical meaning potentials construed in discourse. Addressing concerns that discourse analysis is too often content-free, thematic analysis provides a way to represent semantic structures of mathematical content,…

Qatari intersections with global genetics research and discourse.

PubMed

Kilshaw, Susie

2018-04-01

Genetic discourses have taken a predominant role in approaches to combating a number of conditions that affect Qataris. This paper is derived from an exploration of Qatari encounters with globalizing discourses of genetics, particularly as they relate to notions of risk. It explores Qataris negotiations of global interactions and influences, including the discourses around genetic risk and cousin marriage. It suggests that family marriage can be seen as one of the main platforms of resistance and a means for modern, cosmopolitan and tradition to be negotiated.

Methodology for social accountability: multiple methods and feminist, poststructural, psychoanalytic discourse analysis.

PubMed

Phillips, D A

2001-06-01

Bridging the gap between the individual and social context, methodology that aims to surface and explore the regulatory function of discourse on subjectivity production moves nursing research beyond the individual level in order to theorize social context and its influence on health and well-being. This article describes the feminist, poststructural, psychoanalytic discourse analysis and multiple methods used in a recent study exploring links between cultural discourses of masculinity, performativity of masculinity, and practices of male violence.

Taiwanese and Sri Lankan students' dimensions and discourses of professionalism.

PubMed

Monrouxe, Lynn V; Chandratilake, Madawa; Gosselin, Katherine; Rees, Charlotte E; Ho, Ming-Jung

2017-07-01

The definition of medical professionalism poses a challenge to global medical educators. This is especially pronounced in settings where professionalism frameworks developed in the west are transferred into different cultures. Building upon our previous study across Western contexts, we examine Taiwanese and Sri Lankan medical students' conceptualisations of professionalism in terms of what professionalism comprises (i.e. dimensions) and how it is linguistically framed (i.e. discourses). A qualitative group interview study was undertaken comprising 26 group interviews with 135 participants from one Taiwanese (n = 64; Years 4-7) and one Sri Lankan medical school (n = 71; Years 2-5). Through thematic framework analysis we examined the data for explicit dimensions of professionalism. Through discourse analysis we identified how participants constructed professionalism linguistically (discourses). Thirteen common dimensions across Taiwanese and Sri Lankan talk were identified, with the dimensions (contextual, integration and internalised self) being identified only in Sri Lankan data. Professionalism as knowledge and patient-centredness were dominant dimensions in Taiwan; in Sri Lanka, attributes of the individual and rules were dominant dimensions. Participants in both countries used four types of discourses previously identified in the literature. Individual and interpersonal discourses were dominant in Taiwanese talk; the collective discourse was dominant in Sri Lankan talk. Findings were compared with our previous data collected in Western contexts. Despite some overlap in the dimensions and discourses identified across both this and Western studies, Taiwanese and Sri Lankan students' dominant dimensions and discourses were distinct. We therefore encourage global medical educators to look beyond a one-size-fits-all approach to professionalism, and to recognise the significance of context and culture in conceptualisations of professionalism. © 2017 The Authors. Medical Education published by Association for the Study of Medical Education and John Wiley & Sons Ltd.

Disciplinary discourses: rates of cesarean section explained by medicine, midwifery, and feminism.

PubMed

Lee, Amy Su May; Kirkman, Maggie

2008-05-01

In the context of international concern about increasing rates of cesarean sections, we used discourse analysis to examine explanations arising from feminism and the disciplines of medicine and midwifery, and found that each was positioned differently in relation to the rising rates. Medical discourses asserted that doctors are authorities on birth and that, although cesareans are sometimes medically necessary, women recklessly choose unnecessary cesareans against medical advice. Midwifery discourses portrayed medicine as paternalistic toward both women and midwifery, and feminist discourses situated birth and women's bodies in the context of a patriarchally structured society. The findings illustrate the complex ways in which this intervention in birth is discursively constructed, and demonstrate its significance as a site of disciplinary conflict.

Language, Cognition, and Manipulation in Advertising Discourse

ERIC Educational Resources Information Center

Egorova, Veronika

2013-01-01

This research examines advertising discourse in Russian and English as acts of communicative exchange and interpersonal relationship between advertising discourse participants. The purpose was to identify and describe the way that viewers process information contained in television commercials and how they become consumers moving from getting…

Techniques for Small-Group Discourse

ERIC Educational Resources Information Center

Kilic, Hulya; Cross, Dionne I.; Ersoz, Filyet A.; Mewborn, Denise S.; Swanagan, Diana; Kim, Jisun

2010-01-01

The nature of mathematical discourse and its influence on the development of students' mathematical understanding has received much attention from researchers in recent years. Engaging students in discursive practices can be difficult; teachers can increase their competence in facilitating discourse through greater awareness of the impact of…

Gendered Discourse about Family Business

ERIC Educational Resources Information Center

Danes, Sharon M.; Haberman, Heather R.; McTavish, Donald

2005-01-01

Language patterns of family business owners were explored by identifying discourse styles and emphasized ideas in four presenting contexts: business, family, intersection of family and business, and business success. The content analysis supports the existence of a general discourse style within family businesses and of similarities and…

Discourse Coherence and Cognition after Stroke: A Dual Task Study

ERIC Educational Resources Information Center

Rogalski, Yvonne; Altmann, Lori J. P.; Plummer-D'Amato, Prudence; Behrman, Andrea L.; Marsiske, Michael

2010-01-01

Several researchers have suggested that the maintenance of global coherence (topic maintenance) and local coherence (maintenance between utterances) in discourse requires cognitive resources. This study directly tests this hypothesis by examining the relationship between cognitive variables and coherence in narrative discourse produced by…

Lighting the Way through Scientific Discourse

ERIC Educational Resources Information Center

Yang, Li-hsuan

2008-01-01

This article describes a thought-provoking lesson that compares various arrangements of lamp-battery circuits to help students develop the motivation and competence to participate in scientific discourse for knowledge construction. Through experimentation and discourse, students explore concepts about voltage, current, resistance, and Ohm's law.…

Citizenship Discourses: Production and Curriculum

ERIC Educational Resources Information Center

Olson, Maria; Fejes, Andreas; Dahlstedt, Magnus; Nicoll, Katherine

2015-01-01

This paper explores citizenship discourses empirically through upper secondary school student's understandings, as these emerge in and through their everyday experiences. Drawing on a post-structuralist theorisation inspired by the work of Michel Foucault, a discourse analysis of data from interviews with students is carried out. This analysis…

Profiles of Discourse Recognition

ERIC Educational Resources Information Center

Singer, Murray

2013-01-01

A discourse recognition theory derived from more general memory formulations would be broad in its psychological implications. This study compared discourse recognition with some established profiles of item recognition. Participants read 10 stories either once or twice each. They then rated their confidence in recognizing explicit, paraphrased,…

Inquiry-Based Civil Discourse Education

ERIC Educational Resources Information Center

Linvill, Darren L.; Pyle, Andrew S.

2017-01-01

Course: Civil discourse, argumentation, debate, persuasion, political communication. Objectives: This unit activity will help students build an understanding of civil discourse and its function in society. Students will: (1) increase their capacity to examine arguments critically, (2) enhance their own ability to self-reflect critically, and (3)…

Modeling Narrative Discourse

ERIC Educational Resources Information Center

Elson, David K.

2012-01-01

This thesis describes new approaches to the formal modeling of narrative discourse. Although narratives of all kinds are ubiquitous in daily life, contemporary text processing techniques typically do not leverage the aspects that separate narrative from expository discourse. We describe two approaches to the problem. The first approach considers…

Context updating during sentence comprehension: the effect of aboutness topic.

PubMed

Burmester, Juliane; Spalek, Katharina; Wartenburger, Isabell

2014-10-01

To communicate efficiently, speakers typically link their utterances to the discourse environment and adapt their utterances to the listener's discourse representation. Information structure describes how linguistic information is packaged within a discourse to optimize information transfer. The present study investigates the nature and time course of context integration (i.e., aboutness topic vs. neutral context) on the comprehension of German declarative sentences with either subject-before-object (SO) or object-before-subject (OS) word order using offline comprehensibility judgments and online event-related potentials (ERPs). Comprehensibility judgments revealed that the topic context selectively facilitated comprehension of stories containing OS (i.e., non-canonical) sentences. In the ERPs, the topic context effect was reflected in a less pronounced late positivity at the sentence-initial object. In line with the Syntax-Discourse Model, we argue that these context-induced effects are attributable to reduced processing costs for updating the current discourse model. The results support recent approaches of neurocognitive models of discourse processing. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

The intrusion of the discourse of economics into the clinical space III: economic rationalism and clinical effects.

PubMed

Plastow, Michael

2010-10-01

Language has always been a means of imposing political and economic dominance. The ascendancy of the discourse of economics is examined in the context of economic rationalism. Some of the effects of this discourse, both upon our services, as well as upon different modes of conceptualizing the therapeutic relationship, will be examined in this paper. The intensification of the use of terms from economics and management can be dated from the introduction of neo-liberal policies in our Western democracies, but the economic discourse circulates with a life of its own. The use of the language of economics and management has spread generally through our society. Thus, if the economic discourse is the language utilized by some clinicians, it is also to some degree the language adopted by our patients. It is proposed that the extension of the economic discourse into the clinical field is re-shaping the therapeutic relationship with our patients.

Good Gay Buddies for Lifetime: Homosexually Themed Discourse and the Construction of Heteromasculinity Among Chinese Urban Youth.

PubMed

Wei, Wei

2017-01-01

Starting as an Internet meme, the homosexually themed gao-ji discourse recently became popular among Chinese urban youth in describing intimate relationships among heterosexual men. Positioned within a body of scholarship on the interplay between language, homophobia, and the construction of heteromasculinity, this article suggests that the gao-ji discourse manifests a form of male homosociality, through which new boundaries of Chinese heteromasculinity may be renegotiated. Based on qualitative interviews with college students, the article first tracks the genealogy of the gao-ji discourse in the wake of China's booming Internet culture. The main body focuses on unpacking the daily use of the gao-ji discourse, with an attention to the two latent functions it serves (i.e., expanding heteromasculine behaviors and reiterating heteromasculine identities). In conclusion, I argue that the prevalence of the gao-ji discourse mainly resolves straight men's anxieties against the background of growing public awareness of homosexuality; therefore, it cannot necessarily translate into social acceptance of homosexuality.

The human body as field of conflict between discourses.

PubMed

Kimsma, Gerrit K; Leeuwen, Evert van

2005-01-01

The approach to AIDS as a disease and a threat for social discrimination is used as an example to illustrate a conceptual thesis. This thesis is a claim that concerns what we call a medical issue or not, what is medicalised or needs to be demedicalised. In the friction between medicalisation and demedicalisation as discursive strategies the latter approach can only be effected through the employment of discourses or discursive strategies other than medicine, such as those of the law and of economics. These discourses each realise different values, promote a different subject, and have a different concept of man. The concept of discourse is briefly outlined against concepts such as the linear growth concept of science and the growth model of science as changes in paradigm. The issue of testing for AIDS shows a conflict between the medical and the legal discourse and illustrates the title of our contribution: the human body as field of conflict between discourses.

Psychoanalysis and bioethics: a Lacanian approach to bioethical discourse.

PubMed

Zwart, Hub

2016-12-01

This article aims to develop a Lacanian approach to bioethics. Point of departure is the fact that both psychoanalysis and bioethics are practices of language, combining diagnostics with therapy. Subsequently, I will point out how Lacanian linguistics may help us to elucidate the dynamics of both psychoanalytical and bioethical discourse, using the movie One flew over the Cuckoo's Nest and Sophocles' tragedy Antigone as key examples. Next, I will explain the 'topology' of the bioethical landscape with the help of Lacan's three dimensions: the imaginary, the symbolical and the real. This will culminate in an assessment of the dynamics of bioethical discourse with the help of Lacan's theorem of the four discourses. Bioethics, I will argue, is not a homogeneous discourse. Rather, four modalities of bioethical discourse can be distinguished, all of them displaying specific weaknesses and strengths, opportunities and threats. This will be elucidated with the help of two case studies, namely the debates on human reproductive technologies and on the use of animals as biomedical research models.

Contributing to Meaning Making: Facilitating Discourse in the High School Physics Classroom

NASA Astrophysics Data System (ADS)

Hovan, Scot Alan

The Next Generation Science Standards (NGSS) identify eight practices as essential to science and engineering, and these practices include asking students to construct explanations, to engage in argumentation, and to communicate scientific information. However, few teacher-training programs instruct teachers how to facilitate such discourse in the classroom. Modeling Instruction is one movement in physics education that organizes high school physics content around a small number of student-derived scientific models, and it relies on student discourse for the design, development, and deployment of these models. This research is a self-study of one high school physics teacher's experience facilitating large group discourse in the high school modeling physics classroom. Whiteboard meetings and graded discussions were examined by applying the analytical framework created by Mortimer and Scott (2003) to characterize the classroom talk and the discourse facilitation moves that I employed. In addition, elements of discourse analysis were used to examine some of the tensions that I experienced in the facilitation of this discourse. The findings suggest that deliberate identification of the teaching purposes for the discussion can help determine the scaffolding needed for students to enter the Discourse (Gee, 2011) of being a participant in these large group conversations. In addition, connecting the dialogic dimension of exploring student ideas with the authoritative dimension of introducing the scientific view and supporting the internalization of that view is necessary to contribute to meaning making in the science classroom.

Between negative stigma (cultural deprivation) and positive stigma (learning disability): the historical development of two special education tracks.

PubMed

Katchergin, Ofer

2012-12-01

This article posits an updated, broader perspective on the concept of learning disabilities (LDs) than that accepted in the local Israeli literature, revealing how it is immersed in class, ethnicity, and culture. This is shown through historical description, accreditation, and contrasting of the two special education discourses: the "cultural deprivation" discourse and the "LDs" discourse. There are three sections. Part One presents the theoretical, conceptual, and methodological background of the sociological and discursive debate about LDs. The social-constructivist model used in an analysis of the two categories is proposed as an alternative to the clinical-medical model. The definitions of LDs and cultural deprivation accepted in the Israeli discourse are presented in Part Two. The metamorphoses in the discourse about the category of LDs are uncovered through reference to their conceptual and historical antecedents. This part discusses the various understandings and constructions of learning difficulties. Part Three examines the textual representation of parents of children with disabilities in both cases, exploring the meanings of guilt, responsibility, and agency in each discourse. The conclusion clarifies the social and political significance of the distinct textual and rhetorical representations. It becomes evident that the discourse on LDs and the discourse on cultural deprivation are two special education tracks directed at different target audiences: the culturally enriched audience, well-off and educated on the one hand, and the Mizrahi audience of limited means and education on the other hand.

Older People's Discourses About Euthanasia and Assisted Suicide: A Foucauldian Exploration.

PubMed

Lamers, Carolien P T; Williams, Rebecca R

2016-12-01

This study aims to contribute an alternative understanding of the position of older people in the euthanasia and assisted suicide (EU/AS) debate. Seven interviews were analyzed using Foucauldian discourse analysis, to explore concepts like knowledge, power, subjectification and surveillance. The participants presented a "confused and conflicted" discourse, expressing the view that EU/AS is a family affair, whilst also articulating a strong sense of self-determination. Although a discourse of the medicalization of dying through medical control and surveillance was endorsed, an alternative discourse of "dying outside the medical gaze" emerged. Participants, who were in favor of EU/AS, felt "voiceless," as apparent double standards were applied in the debate, and powerful others, for example, physicians and politicians, seemed reluctant to engage. Within an "aged death" discourse, the anticipated dependency on poor care from (professional) others, made participants consider EU/AS as ways of avoiding this stage of life and the associated loss of dignity. By using Foucauldian discourse analysis, alternative power relationships were revealed which might give a different interpretation to the concept of the "slippery slope." Societal discourses and related behaviors, which devalue the dependent and old, might become internalized by older people, leading them to consider EU/AS as preferable end-of-life options. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Large-scale changes in network interactions as a physiological signature of spatial neglect.

PubMed

Baldassarre, Antonello; Ramsey, Lenny; Hacker, Carl L; Callejas, Alicia; Astafiev, Serguei V; Metcalf, Nicholas V; Zinn, Kristi; Rengachary, Jennifer; Snyder, Abraham Z; Carter, Alex R; Shulman, Gordon L; Corbetta, Maurizio

2014-12-01

The relationship between spontaneous brain activity and behaviour following focal injury is not well understood. Here, we report a large-scale study of resting state functional connectivity MRI and spatial neglect following stroke in a large (n=84) heterogeneous sample of first-ever stroke patients (within 1-2 weeks). Spatial neglect, which is typically more severe after right than left hemisphere injury, includes deficits of spatial attention and motor actions contralateral to the lesion, and low general attention due to impaired vigilance/arousal. Patients underwent structural and resting state functional MRI scans, and spatial neglect was measured using the Posner spatial cueing task, and Mesulam and Behavioural Inattention Test cancellation tests. A principal component analysis of the behavioural tests revealed a main factor accounting for 34% of variance that captured three correlated behavioural deficits: visual neglect of the contralesional visual field, visuomotor neglect of the contralesional field, and low overall performance. In an independent sample (21 healthy subjects), we defined 10 resting state networks consisting of 169 brain regions: visual-fovea and visual-periphery, sensory-motor, auditory, dorsal attention, ventral attention, language, fronto-parietal control, cingulo-opercular control, and default mode. We correlated the neglect factor score with the strength of resting state functional connectivity within and across the 10 resting state networks. All damaged brain voxels were removed from the functional connectivity:behaviour correlational analysis. We found that the correlated behavioural deficits summarized by the factor score were associated with correlated multi-network patterns of abnormal functional connectivity involving large swaths of cortex. Specifically, dorsal attention and sensory-motor networks showed: (i) reduced interhemispheric functional connectivity; (ii) reduced anti-correlation with fronto-parietal and default mode networks in the right hemisphere; and (iii) increased intrahemispheric connectivity with the basal ganglia. These patterns of functional connectivity:behaviour correlations were stronger in patients with right- as compared to left-hemisphere damage and were independent of lesion volume. Our findings identify large-scale changes in resting state network interactions that are a physiological signature of spatial neglect and may relate to its right hemisphere lateralization. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of Eco-economy Harmony and Spatial Evolution of the Urban Agglomeration Area in The Great Pearl River Delta

NASA Astrophysics Data System (ADS)

Wang, Xiuming; Xu, Min; Zhang, Yong; Xu, Naizhong; Zhang, Yuhuan

2018-05-01

Based on the land use data of the study area during 1990 to 2016, the coordination between ecological environment and economy was estimated according to the ESV (ecosystem services value) and EEH (eco-economy harmony) index. The results showed that large amount of farmland and forests were changed to construction land in the study area, due to the rapid urbanization and industrialization. The ESV showed an overall downward trend, the ESV in per hectare was decreased from 1554,000Yuan to 14513,000Yuan. The economic development speed was decreased from 1990 to 2016, the area with high GDP growth rate is changed from the core area of the pearl river delta to the periphery area. The ecology-economy relation in the study area experienced a transformation of “low grade coordination-low grade conflict -further conflict”. Shenzhen, Dongguan, Huizhou, Jiangmen, the central city of Foshan and Guangzhou became the most high-grade conflict areas.

A possible role for a paralemniscal auditory pathway in the coding of slow temporal information

PubMed Central

Abrams, Daniel A.; Nicol, Trent; Zecker, Steven; Kraus, Nina

2010-01-01

Low frequency temporal information present in speech is critical for normal perception, however the neural mechanism underlying the differentiation of slow rates in acoustic signals is not known. Data from the rat trigeminal system suggest that the paralemniscal pathway may be specifically tuned to code low-frequency temporal information. We tested whether this phenomenon occurs in the auditory system by measuring the representation of temporal rate in lemniscal and paralemniscal auditory thalamus and cortex in guinea pig. Similar to the trigeminal system, responses measured in auditory thalamus indicate that slow rates are differentially represented in a paralemniscal pathway. In cortex, both lemniscal and paralemniscal neurons indicated sensitivity to slow rates. We speculate that a paralemniscal pathway in the auditory system may be specifically tuned to code low frequency temporal information present in acoustic signals. These data suggest that somatosensory and auditory modalities have parallel sub-cortical pathways that separately process slow rates and the spatial representation of the sensory periphery. PMID:21094680

Electrical activity controls area-specific expression of neuronal apoptosis in the mouse developing cerebral cortex.

PubMed

Blanquie, Oriane; Yang, Jenq-Wei; Kilb, Werner; Sharopov, Salim; Sinning, Anne; Luhmann, Heiko J

2017-08-21

Programmed cell death widely but heterogeneously affects the developing brain, causing the loss of up to 50% of neurons in rodents. However, whether this heterogeneity originates from neuronal identity and/or network-dependent processes is unknown. Here, we report that the primary motor cortex (M1) and primary somatosensory cortex (S1), two adjacent but functionally distinct areas, display striking differences in density of apoptotic neurons during the early postnatal period. These differences in rate of apoptosis negatively correlate with region-dependent levels of activity. Disrupting this activity either pharmacologically or by electrical stimulation alters the spatial pattern of apoptosis and sensory deprivation leads to exacerbated amounts of apoptotic neurons in the corresponding functional area of the neocortex. Thus, our data demonstrate that spontaneous and periphery-driven activity patterns are important for the structural and functional maturation of the neocortex by refining the final number of cortical neurons in a region-dependent manner.

Transient visual responses reset the phase of low-frequency oscillations in the skeletomotor periphery.

PubMed

Wood, Daniel K; Gu, Chao; Corneil, Brian D; Gribble, Paul L; Goodale, Melvyn A

2015-08-01

We recorded muscle activity from an upper limb muscle while human subjects reached towards peripheral targets. We tested the hypothesis that the transient visual response sweeps not only through the central nervous system, but also through the peripheral nervous system. Like the transient visual response in the central nervous system, stimulus-locked muscle responses (< 100 ms) were sensitive to stimulus contrast, and were temporally and spatially dissociable from voluntary orienting activity. Also, the arrival of visual responses reduced the variability of muscle activity by resetting the phase of ongoing low-frequency oscillations. This latter finding critically extends the emerging evidence that the feedforward visual sweep reduces neural variability via phase resetting. We conclude that, when sensory information is relevant to a particular effector, detailed information about the sensorimotor transformation, even from the earliest stages, is found in the peripheral nervous system. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Measurement of heat load density profile on acceleration grid in MeV-class negative ion accelerator.

PubMed

Hiratsuka, Junichi; Hanada, Masaya; Kojima, Atsushi; Umeda, Naotaka; Kashiwagi, Mieko; Miyamoto, Kenji; Yoshida, Masafumi; Nishikiori, Ryo; Ichikawa, Masahiro; Watanabe, Kazuhiro; Tobari, Hiroyuki

2016-02-01

To understand the physics of the negative ion extraction/acceleration, the heat load density profile on the acceleration grid has been firstly measured in the ITER prototype accelerator where the negative ions are accelerated to 1 MeV with five acceleration stages. In order to clarify the profile, the peripheries around the apertures on the acceleration grid were separated into thermally insulated 34 blocks with thermocouples. The spatial resolution is as low as 3 mm and small enough to measure the tail of the beam profile with a beam diameter of ∼16 mm. It was found that there were two peaks of heat load density around the aperture. These two peaks were also clarified to be caused by the intercepted negative ions and secondary electrons from detailed investigation by changing the beam optics and gas density profile. This is the first experimental result, which is useful to understand the trajectories of these particles.

Variability of surface and underwater nocturnal spectral irradiance with the presence of clouds in urban and peri-urban wetlands.

PubMed

Secondi, Jean; Dupont, Valentin; Davranche, Aurélie; Mondy, Nathalie; Lengagne, Thierry; Théry, Marc

2017-01-01

Artificial light at night (ALAN) is an increasing phenomenon worldwide. It causes a wealth of biological and ecological effects that may eventually affect populations and ecosystems. Despite the growing concern about ALAN, little is known about the light levels species are exposed to at night, especially for wetlands and underwater habitats. We determined nocturnal irradiance in urban and peri-urban wetlands above and under water, and assessed the effect of cloud cover on the variability of ALAN across the urban gradient. Even in aquatic habitats, cloud cover could increase irradiance beyond values observed during clear full moon nights. We report a negative relationship between baseline irradiance and the increase in irradiance during overcast nights. According to this result and previous studies, we propose that the change in the variation regime of ALAN between the urban center and rural land at its periphery is a usual feature. We discuss the ecological and evolutionary implications of this spatial variation in the urban and peri-urban environment.

Quantitative 3D Analysis of Nuclear Morphology and Heterochromatin Organization from Whole-Mount Plant Tissue Using NucleusJ.

PubMed

Desset, Sophie; Poulet, Axel; Tatout, Christophe

2018-01-01

Image analysis is a classical way to study nuclear organization. While nuclear organization used to be investigated by colorimetric or fluorescent labeling of DNA or specific nuclear compartments, new methods in microscopy imaging now enable qualitative and quantitative analyses of chromatin pattern, and nuclear size and shape. Several procedures have been developed to prepare samples in order to collect 3D images for the analysis of spatial chromatin organization, but only few preserve the positional information of the cell within its tissue context. Here, we describe a whole mount tissue preparation procedure coupled to DNA staining using the PicoGreen ® intercalating agent suitable for image analysis of the nucleus in living and fixed tissues. 3D Image analysis is then performed using NucleusJ, an open source ImageJ plugin, which allows for quantifying variations in nuclear morphology such as nuclear volume, sphericity, elongation, and flatness as well as in heterochromatin content and position in respect to the nuclear periphery.

Growth and development of the barnacle Amphibalanus amphitrite: time and spatially resolved structure and chemistry of the base plate

PubMed Central

Burden, Daniel K.; Spillmann, Christopher M.; Everett, Richard K.; Barlow, Daniel E.; Orihuela, Beatriz; Deschamps, Jeffrey R.; Fears, Kenan P.; Rittschof, Daniel; Wahl, Kathryn J.

2014-01-01

The radial growth and advancement of the adhesive interface to the substratum of many species of acorn barnacles occurs underwater and beneath an opaque, calcified shell. Here, the time-dependent growth processes involving various autofluorescent materials within the interface of live barnacles are imaged for the first time using 3D time-lapse confocal microscopy. Key features of the interface development in the striped barnacle, Amphibalanus (= Balanus) amphitrite were resolved in situ and include advancement of the barnacle/substratum interface, epicuticle membrane development, protein secretion, and calcification. Microscopic and spectroscopic techniques provide ex situ material identification of regions imaged by confocal microscopy. In situ and ex situ analysis of the interface support the hypothesis that barnacle interface development is a complex process coupling sequential, timed secretory events and morphological changes. This results in a multi-layered interface that concomitantly fulfills the roles of strongly adhering to a substratum while permitting continuous molting and radial growth at the periphery. PMID:25115515

Foveal Processing Under Concurrent Peripheral Load in Profoundly Deaf Adults

PubMed Central

2016-01-01

Development of the visual system typically proceeds in concert with the development of audition. One result is that the visual system of profoundly deaf individuals differs from that of those with typical auditory systems. While past research has suggested deaf people have enhanced attention in the visual periphery, it is still unclear whether or not this enhancement entails deficits in central vision. Profoundly deaf and typically hearing adults were administered a variant of the useful field of view task that independently assessed performance on concurrent central and peripheral tasks. Identification of a foveated target was impaired by a concurrent selective peripheral attention task, more so in profoundly deaf adults than in the typically hearing. Previous findings of enhanced performance on the peripheral task were not replicated. These data are discussed in terms of flexible allocation of spatial attention targeted towards perceived task demands, and support a modified “division of labor” hypothesis whereby attentional resources co-opted to process peripheral space result in reduced resources in the central visual field. PMID:26657078

Growth and development of the barnacle Amphibalanus amphitrite: time and spatially resolved structure and chemistry of the base plate.

PubMed

Burden, Daniel K; Spillmann, Christopher M; Everett, Richard K; Barlow, Daniel E; Orihuela, Beatriz; Deschamps, Jeffrey R; Fears, Kenan P; Rittschof, Daniel; Wahl, Kathryn J

2014-01-01

The radial growth and advancement of the adhesive interface to the substratum of many species of acorn barnacles occurs underwater and beneath an opaque, calcified shell. Here, the time-dependent growth processes involving various autofluorescent materials within the interface of live barnacles are imaged for the first time using 3D time-lapse confocal microscopy. Key features of the interface development in the striped barnacle, Amphibalanus (= Balanus) amphitrite were resolved in situ and include advancement of the barnacle/substratum interface, epicuticle membrane development, protein secretion, and calcification. Microscopic and spectroscopic techniques provide ex situ material identification of regions imaged by confocal microscopy. In situ and ex situ analysis of the interface support the hypothesis that barnacle interface development is a complex process coupling sequential, timed secretory events and morphological changes. This results in a multi-layered interface that concomitantly fulfills the roles of strongly adhering to a substratum while permitting continuous molting and radial growth at the periphery.

Learning about the history of landscape use for the future: consequences for ecological and social systems in Swedish Bergslagen.

PubMed

Angelstam, Per; Andersson, Kjell; Isacson, Maths; Gavrilov, Dmitri V; Axelsson, Robert; Bäckström, Mattias; Degerman, Erik; Elbakidze, Marine; Kazakova-Apkarimova, Elena Yu; Sartz, Lotta; Sädbom, Stefan; Törnblom, Johan

2013-03-01

Barriers and bridges to implement policies about sustainable development and sustainability commonly depend on the past development of social-ecological systems. Production of metals required integration of use of ore, streams for energy, and wood for bioenergy and construction, as well as of multiple societal actors. Focusing on the Swedish Bergslagen region as a case study we (1) describe the phases of natural resource use triggered by metallurgy, (2) the location and spatial extent of 22 definitions of Bergslagen divided into four zones as a proxy of cumulative pressure on landscapes, and (3) analyze the consequences for natural capital and society. We found clear gradients in industrial activity, stream alteration, and amount of natural forest from the core to the periphery of Bergslagen. Additionally, the legacy of top-down governance is linked to today's poorly diversified business sector and thus municipal vulnerability. Comparing the Bergslagen case study with other similar regions in Russia and Germany, we discuss the usefulness of multiple case studies.

Multiarm spirals on the periphery of disc galaxies

NASA Astrophysics Data System (ADS)

Lubov, Spiegel; Evgeny, Polyachenko

2018-04-01

Spiral patterns in some disc galaxies have two arms in the centre, and three or more arms on the periphery. The same result is also obtained in numerical simulations of stellar and gaseous discs.We argue that such patterns may occur due to fast cooling of the gas, resulting in formation of giant molecular clouds. The timescale of this process is 50 Myr, the factor of 10 shorter than of ordinary secular instability. The giant molecular clouds give rise to multiarm spirals through the mechanism of swing amplification.

Combustor nozzles in gas turbine engines

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

Johnson, Thomas Edward; Keener, Christopher Paul; Stewart, Jason Thurman

2017-09-12

A micro-mixer nozzle for use in a combustor of a combustion turbine engine, the micro-mixer nozzle including: a fuel plenum defined by a shroud wall connecting a periphery of a forward tube sheet to a periphery of an aft tubesheet; a plurality of mixing tubes extending across the fuel plenum for mixing a supply of compressed air and fuel, each of the mixing tubes forming a passageway between an inlet formed through the forward tubesheet and an outlet formed through the aft tubesheet; and a wall mixing tube formed in the shroud wall.