WorldWideScience

Sample records for superior colliculus sc

  1. Whisker-related afferents in superior colliculus.

    Science.gov (United States)

    Castro-Alamancos, Manuel A; Favero, Morgana

    2016-05-01

    Rodents use their whiskers to explore the environment, and the superior colliculus is part of the neural circuits that process this sensorimotor information. Cells in the intermediate layers of the superior colliculus integrate trigeminotectal afferents from trigeminal complex and corticotectal afferents from barrel cortex. Using histological methods in mice, we found that trigeminotectal and corticotectal synapses overlap somewhat as they innervate the lower and upper portions of the intermediate granular layer, respectively. Using electrophysiological recordings and optogenetics in anesthetized mice in vivo, we showed that, similar to rats, whisker deflections produce two successive responses that are driven by trigeminotectal and corticotectal afferents. We then employed in vivo and slice experiments to characterize the response properties of these afferents. In vivo, corticotectal responses triggered by electrical stimulation of the barrel cortex evoke activity in the superior colliculus that increases with stimulus intensity and depresses with increasing frequency. In slices from adult mice, optogenetic activation of channelrhodopsin-expressing trigeminotectal and corticotectal fibers revealed that cells in the intermediate layers receive more efficacious trigeminotectal, than corticotectal, synaptic inputs. Moreover, the efficacy of trigeminotectal inputs depresses more strongly with increasing frequency than that of corticotectal inputs. The intermediate layers of superior colliculus appear to be tuned to process strong but infrequent trigeminal inputs and weak but more persistent cortical inputs, which explains features of sensory responsiveness, such as the robust rapid sensory adaptation of whisker responses in the superior colliculus. Copyright © 2016 the American Physiological Society.

  2. Retinal Origin of Direction Selectivity in the Superior Colliculus

    Science.gov (United States)

    Shi, Xuefeng; Barchini, Jad; Ledesma, Hector Acaron; Koren, David; Jin, Yanjiao; Liu, Xiaorong; Wei, Wei; Cang, Jianhua

    2017-01-01

    Detecting visual features in the environment such as motion direction is crucial for survival. The circuit mechanisms that give rise to direction selectivity in a major visual center, the superior colliculus (SC), are entirely unknown. Here, we optogenetically isolate the retinal inputs that individual direction-selective SC neurons receive and find that they are already selective as a result of precisely converging inputs from similarly-tuned retinal ganglion cells. The direction selective retinal input is linearly amplified by the intracollicular circuits without changing its preferred direction or level of selectivity. Finally, using 2-photon calcium imaging, we show that SC direction selectivity is dramatically reduced in transgenic mice that have decreased retinal selectivity. Together, our studies demonstrate a retinal origin of direction selectivity in the SC, and reveal a central visual deficit as a consequence of altered feature selectivity in the retina. PMID:28192394

  3. Retinal origin of direction selectivity in the superior colliculus.

    Science.gov (United States)

    Shi, Xuefeng; Barchini, Jad; Ledesma, Hector Acaron; Koren, David; Jin, Yanjiao; Liu, Xiaorong; Wei, Wei; Cang, Jianhua

    2017-04-01

    Detecting visual features in the environment, such as motion direction, is crucial for survival. The circuit mechanisms that give rise to direction selectivity in a major visual center, the superior colliculus (SC), are entirely unknown. We optogenetically isolate the retinal inputs that individual direction-selective SC neurons receive and find that they are already selective as a result of precisely converging inputs from similarly tuned retinal ganglion cells. The direction-selective retinal input is linearly amplified by intracollicular circuits without changing its preferred direction or level of selectivity. Finally, using two-photon calcium imaging, we show that SC direction selectivity is dramatically reduced in transgenic mice that have decreased retinal selectivity. Together, our studies demonstrate a retinal origin of direction selectivity in the SC and reveal a central visual deficit as a consequence of altered feature selectivity in the retina.

  4. Spatiotemporal structure of visual receptive fields in macaque superior colliculus.

    Science.gov (United States)

    Churan, Jan; Guitton, Daniel; Pack, Christopher C

    2012-11-01

    Saccades are useful for directing the high-acuity fovea to visual targets that are of behavioral relevance. The selection of visual targets for eye movements involves the superior colliculus (SC), where many neurons respond to visual stimuli. Many of these neurons are also activated before and during saccades of specific directions and amplitudes. Although the role of the SC in controlling eye movements has been thoroughly examined, far less is known about the nature of the visual responses in this area. We have, therefore, recorded from neurons in the intermediate layers of the macaque SC, while using a sparse-noise mapping procedure to obtain a detailed characterization of the spatiotemporal structure of visual receptive fields. We find that SC responses to flashed visual stimuli start roughly 50 ms after the onset of the stimulus and last for on average ~70 ms. About 50% of these neurons are strongly suppressed by visual stimuli flashed at certain locations flanking the excitatory center, and the spatiotemporal pattern of suppression exerts a predictable influence on the timing of saccades. This suppression may, therefore, contribute to the filtering of distractor stimuli during target selection. We also find that saccades affect the processing of visual stimuli by SC neurons in a manner that is quite similar to the saccadic suppression and postsaccadic enhancement that has been observed in the cortex and in perception. However, in contrast to what has been observed in the cortex, decreased visual sensitivity was generally associated with increased firing rates, while increased sensitivity was associated with decreased firing rates. Overall, these results suggest that the processing of visual stimuli by SC receptive fields can influence oculomotor behavior and that oculomotor signals originating in the SC can shape perisaccadic visual perception.

  5. Inflammatory responses in the rat superior colliculus after eye enucleation.

    Science.gov (United States)

    Hernandes, Marina S; Britto, Luiz R G

    2014-02-01

    Ocular enucleation induces profound morphological alterations in central visual areas. However, little is known about the response of glial cells and possible inflammatory processes in visual brain areas resulting from eye enucleation. In this study, immunoblotting and immunostaining assays revealed increased expression of astrocyte and microglia markers in the rat superior colliculus (SC) between 1 and 15 days after contralateral enucleation. A transient increase of neuronal COX-2 protein expression was also found in the SC. To evaluate the role of an anti-inflammatory drug in attenuating both COX-2 and glial cell activation, the synthetic glucocorticoid dexamethasone (DEX) was administered (1 mg/kg i.p., for 3 days) to enucleated rats. Immunoblotting data revealed that DEX treatment significantly inhibited COX-2 protein expression. Postlesion immunostaining for astrocyte and microglia markers was also significantly reduced by DEX treatment. These findings suggest that the removal of retinal ganglion cell input generates inflammatory responses in central retinorecipient structures. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Modeling the value of strategic actions in the superior colliculus

    Directory of Open Access Journals (Sweden)

    Dhushan Thevarajah

    2010-02-01

    Full Text Available In learning models of strategic game play, an agent constructs a valuation (action value over possible future choices as a function of past actions and rewards. Choices are then stochastic functions of these action values. Our goal is to uncover a neural signal that correlates with the action value posited by behavioral learning models. We measured activity from neurons in the superior colliculus (SC, a midbrain region involved in planning saccadic eye movements, in monkeys while they performed two saccade tasks. In the strategic task, monkeys competed against a computer in a saccade version of the mixed-strategy game “matching-pennies”. In the instructed task, stochastic saccades were elicited through explicit instruction rather than free choices. In both tasks, neuronal activity and behavior were shaped by past actions and rewards with more recent events exerting a larger influence. Further, SC activity predicted upcoming choices during the strategic task and upcoming reaction times during the instructed task. Finally, we found that neuronal activity in both tasks correlated with an established learning model, the Experience Weighted Attraction model of action valuation (Ho, Camerer, and Chong, 2007. Collectively, our results provide evidence that action values hypothesized by learning models are represented in the motor planning regions of the brain in a manner that could be used to select strategic actions.

  7. Non-Stationarity in Multisensory Neurons in the Superior Colliculus

    Directory of Open Access Journals (Sweden)

    Thomas J Perrault

    2011-07-01

    Full Text Available The superior colliculus (SC integrates information from multiple sensory modalities to facilitate the detection and localization of salient events. The efficacy of multisensory integration is traditionally measured by comparing the magnitude of the response elicited by a cross-modal stimulus to the responses elicited by its modality-specific component stimuli, and because there is an element of randomness in the system, these calculations are made using response values averaged over multiple stimulus presentations in an experiment. Recent evidence suggests that multisensory integration in the SC is highly plastic and these neurons adapt to specific anomalous stimulus configurations. This raises the question whether such adaptation occurs during an experiment with traditional stimulus configurations; that is, whether the state of the neuron and its integrative principles are the same at the beginning and end of the experiment, or whether they are altered as a consequence of exposure to the testing stimuli even when they are pseudo-randomly interleaved. We find that unisensory and multisensory responses do change during an experiment, and these changes are predictable. Responses that are initially weak tend to potentiate, responses that are initially strong tend to habituate, and the efficacy of multisensory integration waxes or wanes accordingly during the experiment as predicted by the principle of inverse effectiveness. These changes are presumed to reflect two competing mechanisms in the SC: potentiation reflecting increases in the expectation that a stimulus will occur at a given location, habituation reflecting decreases in stimulus novelty. These findings indicate plasticity in multisensory integration that allows animals to adapt to rapidly changing environmental events while suggesting important caveats in the interpretation of experimental data: the neuron studied at the beginning of an experiment is not the same at the end of it.

  8. Preference for concentric orientations in the mouse superior colliculus

    NARCIS (Netherlands)

    Ahmadlou, Mehran; Heimel, J Alexander

    2015-01-01

    The superior colliculus is a layered structure important for body- and gaze-orienting responses. Its superficial layer is, next to the lateral geniculate nucleus, the second major target of retinal ganglion axons and is retinotopically organized. Here we show that in the mouse there is also a

  9. Distinct representation and distribution of visual information by specific cell types in mouse superficial superior colliculus.

    Science.gov (United States)

    Gale, Samuel D; Murphy, Gabe J

    2014-10-01

    The superficial superior colliculus (sSC) occupies a critical node in the mammalian visual system; it is one of two major retinorecipient areas, receives visual cortical input, and innervates visual thalamocortical circuits. Nonetheless, the contribution of sSC neurons to downstream neural activity and visually guided behavior is unknown and frequently neglected. Here we identified the visual stimuli to which specific classes of sSC neurons respond, the downstream regions they target, and transgenic mice enabling class-specific manipulations. One class responds to small, slowly moving stimuli and projects exclusively to lateral posterior thalamus; another, comprising GABAergic neurons, responds to the sudden appearance or rapid movement of large stimuli and projects to multiple areas, including the lateral geniculate nucleus. A third class exhibits direction-selective responses and targets deeper SC layers. Together, our results show how specific sSC neurons represent and distribute diverse information and enable direct tests of their functional role.

  10. Endogenous attention signals evoked by threshold contrast detection in human superior colliculus.

    Science.gov (United States)

    Katyal, Sucharit; Ress, David

    2014-01-15

    Human superior colliculus (SC) responds in a retinotopically selective manner when attention is deployed on a high-contrast visual stimulus using a discrimination task. To further elucidate the role of SC in endogenous visual attention, high-resolution fMRI was used to demonstrate that SC also exhibits a retinotopically selective response for covert attention in the absence of significant visual stimulation using a threshold-contrast detection task. SC neurons have a laminar organization according to their function, with visually responsive neurons present in the superficial layers and visuomotor neurons in the intermediate layers. The results show that the response evoked by the threshold-contrast detection task is significantly deeper than the response evoked by the high-contrast speed discrimination task, reflecting a functional dissociation of the attentional enhancement of visuomotor and visual neurons, respectively. Such a functional dissociation of attention within SC laminae provides a subcortical basis for the oculomotor theory of attention.

  11. Cortical projections to the superior colliculus in tree shrews (Tupaia belangeri).

    Science.gov (United States)

    Baldwin, Mary K L; Wei, Haiyang; Reed, Jamie L; Bickford, Martha E; Petry, Heywood M; Kaas, Jon H

    2013-05-01

    The visuomotor functions of the superior colliculus depend not only on direct inputs from the retina, but also on inputs from neocortex. As mammals vary in the areal organization of neocortex, and in the organization of the number of visual and visuomotor areas, patterns of corticotectal projections vary. Primates in particular have a large number of visual areas projecting to the superior colliculus. As tree shrews are close relatives of primates, and they are also highly visual, we studied the distribution of cortical neurons projecting to the superior colliculus by injecting anatomical tracers into the colliculus. Since projections from visuotopically organized visual areas are expected to match the visuotopy of the superior colliculus, injections at different retinotopic locations in the superior colliculus provide information about the locations and organization of topographic areas in extrastriate cortex. Small injections in the superior colliculus labeled neurons in locations within areas 17 (V1) and 18 (V2) that are consistent with the known topography of these areas and the superior colliculus. In addition, the separate locations of clusters of labeled cells in temporal visual cortex provide evidence for five or more topographically organized areas. Injections that included deeper layers of the superior colliculus also labeled neurons in medial frontal cortex, likely in premotor cortex. Only occasional labeled neurons were observed in somatosensory or auditory cortex. Regardless of tracer injection location, we found that, unlike primates, a substantial projection to the superior colliculus from posterior parietal cortex is not a characteristic of tree shrews.

  12. Modeling the minimal newborn's intersubjective mind: the visuotopic-somatotopic alignment hypothesis in the superior colliculus.

    Directory of Open Access Journals (Sweden)

    Alexandre Pitti

    Full Text Available The question whether newborns possess inborn social skills is a long debate in developmental psychology. Fetal behavioral and anatomical observations show evidences for the control of eye movements and facial behaviors during the third trimester of pregnancy whereas specific sub-cortical areas, like the superior colliculus (SC and the striatum appear to be functionally mature to support these behaviors. These observations suggest that the newborn is potentially mature for developing minimal social skills. In this manuscript, we propose that the mechanism of sensory alignment observed in SC is particularly important for enabling the social skills observed at birth such as facial preference and facial mimicry. In a computational simulation of the maturing superior colliculus connected to a simulated facial tissue of a fetus, we model how the incoming tactile information is used to direct visual attention toward faces. We suggest that the unisensory superficial visual layer (eye-centered and the deep somatopic layer (face-centered in SC are combined into an intermediate layer for visuo-tactile integration and that multimodal alignment in this third layer allows newborns to have a sensitivity to configuration of eyes and mouth. We show that the visual and tactile maps align through a Hebbian learning stage and and strengthen their synaptic links from each other into the intermediate layer. It results that the global network produces some emergent properties such as sensitivity toward the spatial configuration of face-like patterns and the detection of eyes and mouth movement.

  13. Direct projections from the dorsal premotor cortex to the superior colliculus in the macaque (macaca mulatta).

    Science.gov (United States)

    Distler, Claudia; Hoffmann, Klaus-Peter

    2015-11-01

    The dorsal premotor cortex (PMd) is part of the cortical network for arm movements during reach-related behavior. Here we investigate the neuronal projections from the PMd to the midbrain superior colliculus (SC), which also contains reach-related neurons, to investigate how the SC integrates into a cortico-subcortical network responsible for initiation and modulation of goal-directed arm movements. By using anterograde transport of neuronal tracers, we found that the PMd projects most strongly to the deep layers of the lateral part of the SC and the underlying reticular formation corresponding to locations where reach-related neurons have been recorded, and from where descending tectofugal projections arise. A somewhat weaker projection targets the intermediate layers of the SC. By contrast, terminals originating from prearcuate area 8 mainly project to the intermediate layers of the SC. Thus, this projection pattern strengthens the view that different compartments in the SC are involved in the control of gaze and in the control or modulation of reaching movements. The PMD-SC projection assists in the participation of the SC in the skeletomotor system and provides the PMd with a parallel path to elicit forelimb movements.

  14. The Histopathological Effect of Sildenafil Citrate on Superior Colliculus of Adult Male Rat

    Directory of Open Access Journals (Sweden)

    Amany Shams

    2013-08-01

    Full Text Available Objective: Preclinical and very limited clinical studies suggest that sildenafil may have therapeutic potential in selected neurological disorders. However, many neurological side effects of sildenafil have been reported. This work aimed to clarify the histopathological effect of sildenafil citrate on the superior colliculus (SC of adult male albino rat. Material and methods: 24 adult male albino rats were used and divided into 4 groups. The first 3 groups were received respectively sildenafil citrate orally at doses 0.25, 0.70 and 1.43mg/kg body weight daily for 30 days while the 4th group was used as control. At end of the treatment, the superior colliculi were undergone light and electron microscopic investigation. Results: In the control group, superficial part of the SC has neural cells and myelinated nerve fibers. With least dose of sildenafil, the superficial part of SC revealed disturbance in neural tissue with dilated capillaries and vacuoles. Some neurons showed deeply stained nuclei shrunken cytoplasm. Some cells showed enlarged mitochondria and dilated endoplasmic reticulum. With medium dose of sildenafil, SC showed more disturbances; stripped myelin sheaths or widely separated myelin lamellae, dilated blood vessels with large vacuoles around them and many neurons with apoptotic criteria. However, maximum dose of sildenafil induced massive destruction of edematous neural tissue; invasion of the surface with massive blood vessels, marked decrease in thickness of myelin sheaths and the neural cells revealed degenerative and apoptotic changes. The mean number and size of cells revealed significantly progressive decrease in all treated rats with increasing doses of the drug. Conclusion: Long-term, daily use of sildenafil can lead to pathological effect in the superior colliculus which may be implicated in visual disturbance and this effect is dose dependent, so neurological effect of sildenafil necessitates further investigations. [J

  15. Heterogeneity in the spatial receptive field architecture of multisensory neurons of the superior colliculus and its effects on multisensory integration

    OpenAIRE

    Ghose, Dipanwita; Wallace, Mark T.

    2013-01-01

    Multisensory integration has been widely studied in neurons of the mammalian superior colliculus (SC). This has led to the description of various determinants of multisensory integration, including those based on stimulus- and neuron-specific factors. The most widely characterized of these illustrate the importance of the spatial and temporal relationships of the paired stimuli as well as their relative effectiveness in eliciting a response in determining the final integrated output. Although...

  16. Multisensory Response Modulation in the Superficial Layers of the Superior Colliculus

    Science.gov (United States)

    Maier, Alexander; Nidiffer, Aaron; Wallace, Mark T.

    2014-01-01

    The mammalian superior colliculus (SC) is made up of seven distinct layers. Based on overall differences in neuronal morphology, afferent and efferent projection patterns, physiological properties, and presumptive behavioral role, the upper three layers have been classically grouped together as the superficial layers and the remaining four layers collectively make up the deep layers. Although the superficial layers receive their primary inputs from the retina and primary visual cortex, the deep layers receive inputs from extrastriate visual cortical areas and from auditory, somatosensory, and motor-related structures. In contrast, there is no evidence of monosynaptic nonvisual inputs to the superficial layers. However, more recent studies have revealed anatomical connections between the superficial and deep layers, thus providing the substrate for possible communication between these two functional divisions of the SC. In this study, we provide physiological evidence for auditory influences on visual responses in the superficial layers of the SC. Using extracellular recordings of local field potentials (LFPs) and multiunit activity, we demonstrate multisensory effects in the superficial layers of the cat SC such that subthreshold auditory activity (as seen in the LFP) modulates visual responses (reflected in spiking activity) when the two stimuli are presented together. These results have important implications for our understanding of the functional organization of the SC and for the neural basis of multisensory integration in general. PMID:24647954

  17. A Model of the Superior Colliculus Predicts Fixation Locations during Scene Viewing and Visual Search.

    Science.gov (United States)

    Adeli, Hossein; Vitu, Françoise; Zelinsky, Gregory J

    2017-02-08

    Modern computational models of attention predict fixations using saliency maps and target maps, which prioritize locations for fixation based on feature contrast and target goals, respectively. But whereas many such models are biologically plausible, none have looked to the oculomotor system for design constraints or parameter specification. Conversely, although most models of saccade programming are tightly coupled to underlying neurophysiology, none have been tested using real-world stimuli and tasks. We combined the strengths of these two approaches in MASC, a model of attention in the superior colliculus (SC) that captures known neurophysiological constraints on saccade programming. We show that MASC predicted the fixation locations of humans freely viewing naturalistic scenes and performing exemplar and categorical search tasks, a breadth achieved by no other existing model. Moreover, it did this as well or better than its more specialized state-of-the-art competitors. MASC's predictive success stems from its inclusion of high-level but core principles of SC organization: an over-representation of foveal information, size-invariant population codes, cascaded population averaging over distorted visual and motor maps, and competition between motor point images for saccade programming, all of which cause further modulation of priority (attention) after projection of saliency and target maps to the SC. Only by incorporating these organizing brain principles into our models can we fully understand the transformation of complex visual information into the saccade programs underlying movements of overt attention. With MASC, a theoretical footing now exists to generate and test computationally explicit predictions of behavioral and neural responses in visually complex real-world contexts.SIGNIFICANCE STATEMENT The superior colliculus (SC) performs a visual-to-motor transformation vital to overt attention, but existing SC models cannot predict saccades to visually

  18. Orientational and directional selectivities of visual neurons in the superior colliculus of the cat

    Institute of Scientific and Technical Information of China (English)

    李兵; 王磊; 王毅; 刁云程

    1996-01-01

    Based on quantitative analyses of the response characteristics of visual neurons in the superior colliculus to moving optical bar stimuli, it is demonstrated for the first time that the visual neurons in superior colliculus of the cat have, to some extent, orientational selectivity. The significance of this selectivity is discussed in reference to its morphological substrate and physiological functions. In addition, both the directional and orientational selectivities in the superior colliculus are relatively weak when compared with those in the primary visual cortex, and the majority of the neurons prefer upward or downward motion in the visual field.

  19. Spatial determinants of multisensory integration in cat superior colliculus neurons.

    Science.gov (United States)

    Meredith, M A; Stein, B E

    1996-05-01

    1. Although a representation of multisensory space is contained in the superior colliculus, little is known about the spatial requirements of multisensory stimuli that influence the activity of neurons here. Critical to this problem is an assessment of the registry of the different receptive fields within individual multisensory neurons. The present study was initiated to determine how closely the receptive fields of individual multisensory neurons are aligned, the physiological role of that alignment, and the possible functional consequences of inducing receptive-field misalignment. 2. Individual multisensory neurons in the superior colliculus of anesthetized, paralyzed cats were studied with the use of standard extracellular recording techniques. The receptive fields of multisensory neurons were large, as reported previously, but exhibited a surprisingly high degree of spatial coincidence. The average proportion of receptive-field overlap was 86% for the population of visual-auditory neurons sampled. 3. Because of this high degree of intersensory receptive-field correspondence, combined-modality stimuli that were coincident in space tended to fall within the excitatory regions of the receptive fields involved. The result was a significantly enhanced neuronal response in 88% of the multisensory neurons studied. If stimuli were spatially disparate, so that one fell outside its receptive field, either a decreased response occurred (56%), or no intersensory effect was apparent (44%). 4. The normal alignment of the different receptive fields of a multisensory neuron could be disrupted by passively displacing the eyes, pinnae, or limbs/body. In no case was a shift in location or size observed in a neuron's other receptive field(s) to compensate for this displacement. The physiological result of receptive-field misalignment was predictable and based on the location of the stimuli relative to the new positions of their respective receptive fields. Now, for example, one

  20. Age-related audiovisual interactions in the superior colliculus of the rat.

    Science.gov (United States)

    Costa, M; Piché, M; Lepore, F; Guillemot, J-P

    2016-04-21

    It is well established that multisensory integration is a functional characteristic of the superior colliculus that disambiguates external stimuli and therefore reduces the reaction times toward simple audiovisual targets in space. However, in a condition where a complex audiovisual stimulus is used, such as the optical flow in the presence of modulated audio signals, little is known about the processing of the multisensory integration in the superior colliculus. Furthermore, since visual and auditory deficits constitute hallmark signs during aging, we sought to gain some insight on whether audiovisual processes in the superior colliculus are altered with age. Extracellular single-unit recordings were conducted in the superior colliculus of anesthetized Sprague-Dawley adult (10-12 months) and aged (21-22 months) rats. Looming circular concentric sinusoidal (CCS) gratings were presented alone and in the presence of sinusoidally amplitude modulated white noise. In both groups of rats, two different audiovisual response interactions were encountered in the spatial domain: superadditive, and suppressive. In contrast, additive audiovisual interactions were found only in adult rats. Hence, superior colliculus audiovisual interactions were more numerous in adult rats (38%) than in aged rats (8%). These results suggest that intersensory interactions in the superior colliculus play an essential role in space processing toward audiovisual moving objects during self-motion. Moreover, aging has a deleterious effect on complex audiovisual interactions.

  1. BOLD temporal dynamics of rat superior colliculus and lateral geniculate nucleus following short duration visual stimulation.

    Directory of Open Access Journals (Sweden)

    Condon Lau

    Full Text Available BACKGROUND: The superior colliculus (SC and lateral geniculate nucleus (LGN are important subcortical structures for vision. Much of our understanding of vision was obtained using invasive and small field of view (FOV techniques. In this study, we use non-invasive, large FOV blood oxygenation level-dependent (BOLD fMRI to measure the SC and LGN's response temporal dynamics following short duration (1 s visual stimulation. METHODOLOGY/PRINCIPAL FINDINGS: Experiments are performed at 7 tesla on Sprague Dawley rats stimulated in one eye with flashing light. Gradient-echo and spin-echo sequences are used to provide complementary information. An anatomical image is acquired from one rat after injection of monocrystalline iron oxide nanoparticles (MION, a blood vessel contrast agent. BOLD responses are concentrated in the contralateral SC and LGN. The SC BOLD signal measured with gradient-echo rises to 50% of maximum amplitude (PEAK 0.2±0.2 s before the LGN signal (p<0.05. The LGN signal returns to 50% of PEAK 1.4±1.2 s before the SC signal (p<0.05. These results indicate the SC signal rises faster than the LGN signal but settles slower. Spin-echo results support these findings. The post-MION image shows the SC and LGN lie beneath large blood vessels. This subcortical vasculature is similar to that in the cortex, which also lies beneath large vessels. The LGN lies closer to the large vessels than much of the SC. CONCLUSIONS/SIGNIFICANCE: The differences in response timing between SC and LGN are very similar to those between deep and shallow cortical layers following electrical stimulation, which are related to depth-dependent blood vessel dilation rates. This combined with the similarities in vasculature between subcortex and cortex suggest the SC and LGN timing differences are also related to depth-dependent dilation rates. This study shows for the first time that BOLD responses in the rat SC and LGN following short duration visual stimulation are

  2. Adult plasticity of spatiotemporal receptive fields of multisensory superior colliculus neurons following early visual deprivation

    Science.gov (United States)

    Royal, David W.; Krueger, Juliane; Fister, Matthew C.; Wallace, Mark T.

    2013-01-01

    Purpose Previous work has established that the integrative capacity of multisensory neurons in the superior colliculus (SC) matures over a protracted period of postnatal life (Wallace and Stein, 1997), and that the development of normal patterns of multisensory integration depends critically on early sensory experience (Wallace et al., 2004). Although these studies demonstrated the importance of early sensory experience in the creation of mature multisensory circuits, it remains unknown whether the reestablishment of sensory experience in adulthood can reverse these effects and restore integrative capacity. Methods The current study tested this hypothesis in cats that were reared in absolute darkness until adulthood and then returned to a normal housing environment for an equivalent period of time. Single unit extracellular recordings targeted multisensory neurons in the deep layers of the SC, and analyses were focused on both conventional measures of multisensory integration and on more recently developed methods designed to characterize spatiotemporal receptive fields (STRF). Results Analysis of the STRF structure and integrative capacity of multisensory SC neurons revealed significant modifications in the temporal response dynamics of multisensory responses (e.g., discharge durations, peak firing rates, and mean firing rates), as well as significant changes in rates of spontaneous activation and degrees of multisensory integration. Conclusions These results emphasize the importance of early sensory experience in the establishment of normal multisensory processing architecture and highlight the limited plastic potential of adult multisensory circuits. PMID:20404413

  3. Whisker motor cortex reorganization after superior colliculus output suppression in adult rats.

    Science.gov (United States)

    Veronesi, Carlo; Maggiolini, Emma; Franchi, Gianfranco

    2013-10-01

    The effect of unilateral superior colliculus (SC) output suppression on the ipsilateral whisker motor cortex (WMC) was studied at different time points after tetrodotoxin and quinolinic acid injections, in adult rats. The WMC output was assessed by mapping the movement evoked by intracortical microstimulation (ICMS) and by recording the ICMS-evoked electromyographic (EMG) responses from contralateral whisker muscles. At 1 h after SC injections, the WMC showed: (i) a strong decrease in contralateral whisker sites, (ii) a strong increase in ipsilateral whisker sites and in ineffective sites, and (iii) a strong increase in threshold current values. At 6 h after injections, the WMC size had shrunk to 60% of the control value and forelimb representation had expanded into the lateral part of the normal WMC. Thereafter, the size of the WMC recovered, returning to nearly normal 12 h later (94% of control) and persisted unchanged over time (1-3 weeks). The ICMS-evoked EMG response area decreased at 1 h after SC lesion and had recovered its baseline value 12 h later. Conversely, the latency of ICMS-evoked EMG responses had increased by 1 h and continued to increase for as long as 3 weeks following the lesion. These findings provide physiological evidence that SC output suppression persistently withdrew the direct excitatory drive from whisker motoneurons and induced changes in the WMC. We suggest that the changes in the WMC are a form of reversible short-term reorganization that is induced by SC lesion. The persistent latency increase in the ICMS-evoked EMG response suggested that the recovery of basic WMC excitability did not take place with the recovery of normal explorative behaviour. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  4. Spectral and temporal auditory processing in the superior colliculus of aged rats.

    Science.gov (United States)

    Costa, Margarida; Lepore, Franco; Guillemot, Jean-Paul

    2017-09-01

    Presbyacusis reflects dysfunctions present along the central auditory pathway. Given that the topographic representation of the auditory directional spatial map is deteriorated in the superior colliculus of aged animals, therefore, are spectral and temporal auditory processes altered with aging in the rat's superior colliculus? Extracellular single-unit recordings were conducted in the superior colliculus of anesthetized Sprague-Dawley adult (10 months) and aged (22 months) rats. In the spectral domain, level thresholds in aged rats were significantly increased when superior colliculus auditory neurons were stimulated with pure tones or Gaussian noise bursts. The sharpness of the frequency response tuning curve at 10 dB SPL above threshold was also significantly broader among the aged rats. Furthermore, in the temporal domain, the minimal silent gap thresholds to Gaussian noises were significantly longer in aged rats. Hence, these results highlight that spectral and temporal auditory processing in the superior colliculus are impaired during aging. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Linking express saccade occurance to stimulus properties and sensorimotor integration in the superior colliculus.

    Science.gov (United States)

    Marino, Robert A; Levy, Ron; Munoz, Douglas P

    2015-08-01

    Express saccades represent the fastest possible eye movements to visual targets with reaction times that approach minimum sensory-motor conduction delays. Previous work in monkeys has identified two specific neural signals in the superior colliculus (SC: a midbrain sensorimotor integration structure involved in gaze control) that are required to execute express saccades: 1) previsual activity consisting of a low-frequency increase in action potentials in sensory-motor neurons immediately before the arrival of a visual response; and 2) a transient visual-sensory response consisting of a high-frequency burst of action potentials in visually responsive neurons resulting from the appearance of a visual target stimulus. To better understand how these two neural signals interact to produce express saccades, we manipulated the arrival time and magnitude of visual responses in the SC by altering target luminance and we examined the corresponding influences on SC activity and express saccade generation. We recorded from saccade neurons with visual-, motor-, and previsual-related activity in the SC of monkeys performing the gap saccade task while target luminance was systematically varied between 0.001 and 42.5 cd/m(2) against a black background (∼0.0001 cd/m(2)). Our results demonstrated that 1) express saccade latencies were linked directly to the arrival time in the SC of visual responses produced by abruptly appearing visual stimuli; 2) express saccades were generated toward both dim and bright targets whenever sufficient previsual activity was present; and 3) target luminance altered the likelihood of producing an express saccade. When an express saccade was generated, visuomotor neurons increased their activity immediately before the arrival of the visual response in the SC and saccade initiation. Furthermore, the visual and motor responses of visuomotor neurons merged into a single burst of action potentials, while the visual response of visual-only neurons was

  6. Spatial transformations between superior colliculus visual and motor response fields during head-unrestrained gaze shifts.

    Science.gov (United States)

    Sadeh, Morteza; Sajad, Amirsaman; Wang, Hongying; Yan, Xiaogang; Crawford, John Douglas

    2015-12-01

    We previously reported that visuomotor activity in the superior colliculus (SC)--a key midbrain structure for the generation of rapid eye movements--preferentially encodes target position relative to the eye (Te) during low-latency head-unrestrained gaze shifts (DeSouza et al., 2011). Here, we trained two monkeys to perform head-unrestrained gaze shifts after a variable post-stimulus delay (400-700 ms), to test whether temporally separated SC visual and motor responses show different spatial codes. Target positions, final gaze positions and various frames of reference (eye, head, and space) were dissociated through natural (untrained) trial-to-trial variations in behaviour. 3D eye and head orientations were recorded, and 2D response field data were fitted against multiple models by use of a statistical method reported previously (Keith et al., 2009). Of 60 neurons, 17 showed a visual response, 12 showed a motor response, and 31 showed both visual and motor responses. The combined visual response field population (n = 48) showed a significant preference for Te, which was also preferred in each visual subpopulation. In contrast, the motor response field population (n = 43) showed a preference for final (relative to initial) gaze position models, and the Te model was statistically eliminated in the motor-only population. There was also a significant shift of coding from the visual to motor response within visuomotor neurons. These data confirm that SC response fields are gaze-centred, and show a target-to-gaze transformation between visual and motor responses. Thus, visuomotor transformations can occur between, and even within, neurons within a single frame of reference and brain structure.

  7. The superior colliculus is sensitive to gestalt-like stimulus configuration in hemispherectomy patients.

    Science.gov (United States)

    Georgy, Loraine; Celeghin, Alessia; Marzi, Carlo A; Tamietto, Marco; Ptito, Alain

    2016-08-01

    Patients with cortical blindness following a lesion to the primary visual cortex (V1) may retain nonconscious visual abilities (blindsight). One intriguing, though largely unexplored question, is whether nonconscious vision in the blind hemifield of hemianopic patients can be sensitive to higher-order perceptual organization, and which V1-independent structure underlies such effect. To answer this question, we tested two rare hemianopic patients who had undergone hemispherectomy, and in whom the only post-chiasmatic visual structure left intact in the same side of the otherwise damaged hemisphere was the superior colliculus (SC). By using a variant of the redundant target effect (RTE), we presented single dots, patterns composed by the same dots organized in quadruple gestalt-like configurations, or patterns of four dots arranged in random configurations, either singly to the intact visual hemifield or bilaterally to both hemifields. As reported in a number of prior studies on blindsight patients, we found that bilateral stimulation yielded faster reaction times (RTs) than single stimulation of the intact field for all conditions (i.e., there was an implicit RTE). In addition to this effect, both patients showed a further speeding up of RTs when the gestalt-like, but not the random shape, quadruple patterns were projected to their blind hemifield during bilateral stimulation. Because other retino-recipient subcortical and cortical structures in the damaged hemisphere are absent, the SC on the lesioned side seems solely responsible for such an effect. The present results provide initial support to the notion that nonconscious vision might be sensitive to perceptual organization and stimulus configuration through the pivotal contribution of the SC, which can enhance the processing of gestalt-like or structured stimuli over meaningless or randomly assembled ones and translate them into facilitatory motor outputs. Copyright © 2016 The Authors. Published by Elsevier

  8. Sources of subcortical projections to the superior colliculus in the cat.

    Science.gov (United States)

    Edwards, S B; Ginsburgh, C L; Henkel, C K; Stein, B E

    1979-03-15

    A comprehensive search for subcortical projections to the cat superior colliculus was conducted using the retrograde horseradish peroxidase (HRP) method. Over 40 different subcortical structures project to the superior colliculus. The more notable among these are grouped under the following categories. Visual structures: ventral lateral geniculate nucleus, parabigeminal nucleus, pretectal area (nucleus of the optic tract, posterior pretectal nucleus, nuclei of the posterior commissure). Auditory structures: inferior colliculus (external and pericentral nuclei), dorsomedial periolivary nucleus, nuclei of the trapezoid body, ventral nucleus of the lateral lemniscus. Somatosensory structures: sensory trigeminal complex (all divisions, but mainly the gamma division of nucleus oralis), dorsal column nuclei (mostly cuneate nucleus), and the lateral cervical nucleus. Catecholamine nuclei: locus coeruleus, raphe dorsalis, and the parabrachial nuclei. Cerebellum: medial, interposed, and lateral nuclei, and the perihypoglossal nuclei. Reticular areas: zona incerta, substantia nigra, midbrain tegmentum, nucleus paragigantocellularis lateralis, and the hypothalamus. Evidence is presented that only the parabigeminal nucleus, the nucleus of the optic tract, and the posterior pretectal nucleus project to the superficial collicular layers (striatum griseum superficiale and stratum opticum), while all other afferents terminate in the deeper layers of the colliculus. Also presented is information concerning the rostrocaudal distribution of some of these afferent connections. These findings stress the multiplicity and diversity of inputs to the deeper collicular layers, and more specifically, identify multiple sources of the physiologically well-known representations of the somatic and auditory modalities in the colliculus.

  9. Competition driven by retinal waves promotes morphological and functional synaptic development of neurons in the superior colliculus.

    Science.gov (United States)

    Furman, Moran; Xu, Hong-Ping; Crair, Michael C

    2013-09-01

    Prior to eye opening, waves of spontaneous activity sweep across the developing retina. These "retinal waves," together with genetically encoded molecular mechanisms, mediate the formation of visual maps in the brain. However, the specific role of wave activity in synapse development in retino-recipient brain regions is unclear. Here we compare the functional development of synapses and the morphological development of neurons in the superior colliculus (SC) of wild-type (WT) and transgenic (β2-TG) mice in which retinal wave propagation is spatially truncated (Xu HP, Furman M, Mineur YS, Chen H, King SL, Zenisek D, Zhou ZJ, Butts DA, Tian N, Picciotto MR, Crair MC. Neuron 70: 1115-1127, 2011). We use two recently developed brain slice preparations to examine neurons and synapses in the binocular vs. mainly monocular SC. We find that retinocollicular synaptic strength is reduced whereas the number of retinal inputs is increased in the binocular SC of β2-TG mice compared with WT mice. In contrast, in the mainly monocular SC the number of retinal inputs is normal in β2-TG mice, but, transiently, synapses are abnormally strong, possibly because of enhanced activity-dependent competition between local, "small" retinal wave domains. These findings demonstrate that retinal wave size plays an instructive role in the synaptic and morphological development of SC neurons, possibly through a competitive process among retinofugal axons.

  10. Physiological properties of neurons in superficial layers of superior colliculus of rabbits

    Institute of Scientific and Technical Information of China (English)

    刘剑; 罗茀荪

    1996-01-01

    Neurons in superficial layers of the superior colliculus of the rabbit are classified into three types by their electrophysiological properties. Among them, two types belong to projecting neurons which send axons to the thalamic pulvinar (N=52) and dorsal lateral geniculate nucleus (N = 54) respectively. All other neurons are pooled into the third type (N=99). Projecting neurons of both types receive monosynaptic visual inputs via optic tract fibers of similar conduction velocity, indicating that in the superior colliculus of the rabbit, there is no difference in conduction velocity between the two pathways. They also receive trisynaptic inhibitory inputs, most likely via recurrent inhibitory circuits. The third type of neurons receives disynaptic optic and trisynaptic inhibitory inputs. The function of neurons of the third type is studied.

  11. A neural locus for spatial-frequency specific saccadic suppression in visual-motor neurons of the primate superior colliculus.

    Science.gov (United States)

    Chen, Chih-Yang; Hafed, Ziad M

    2017-04-01

    Saccades cause rapid retinal-image shifts that go perceptually unnoticed several times per second. The mechanisms for saccadic suppression have been controversial, in part because of sparse understanding of neural substrates. In this study we uncovered an unexpectedly specific neural locus for spatial frequency-specific saccadic suppression in the superior colliculus (SC). We first developed a sensitive behavioral measure of suppression in two macaque monkeys, demonstrating selectivity to low spatial frequencies similar to that observed in earlier behavioral studies. We then investigated visual responses in either purely visual SC neurons or anatomically deeper visual motor neurons, which are also involved in saccade generation commands. Surprisingly, visual motor neurons showed the strongest visual suppression, and the suppression was dependent on spatial frequency, as in behavior. Most importantly, suppression selectivity for spatial frequency in visual motor neurons was highly predictive of behavioral suppression effects in each individual animal, with our recorded population explaining up to ~74% of behavioral variance even on completely different experimental sessions. Visual SC neurons had mild suppression, which was unselective for spatial frequency and thus only explained up to ~48% of behavioral variance. In terms of spatial frequency-specific saccadic suppression, our results run contrary to predictions that may be associated with a hypothesized SC saccadic suppression mechanism, in which a motor command in the visual motor and motor neurons is first relayed to the more superficial purely visual neurons, to suppress them and to then potentially be fed back to cortex. Instead, an extraretinal modulatory signal mediating spatial-frequency-specific suppression may already be established in visual motor neurons.NEW & NOTEWORTHY Saccades, which repeatedly realign the line of sight, introduce spurious signals in retinal images that normally go unnoticed. In

  12. Time-dependent changes in eye-specific segregation in the dorsal lateral geniculate nucleus and superior colliculus of postnatal mice

    Institute of Scientific and Technical Information of China (English)

    Yu-qing CHEN; Yu-pu DIAO; Jing-gang DUAN; Li-yuan CUI; Jia-yi ZHANG

    2014-01-01

    Eye-specific segregation in the dorsal lateral geniculate nucleus (dLGN) and superior colliculus (SC) starts from the embryonic stage and continues to develop postnatally until eye-opening in mice. However, there have been few systematic studies on the details of this developmental process. Here, we carried out time-dependent studies of eye-specific segregation in the dLGN and SC. Our results demonstrated that the development of eye-specific segregation in the SC is completed before postnatal day 12 (P12), which is earlier than in the dLGN (P20). During the whole period, ipsilateral and overlapping axonal projections decreased continuously in both the dLGN and SC. On the other hand, contralateral axonal projections showed little change, except for a slight decrease between P8 and P20 in the dLGN.

  13. Heterogeneity in the spatial receptive field architecture of multisensory neurons of the superior colliculus and its effects on multisensory integration

    Science.gov (United States)

    Ghose, Dipanwita; Wallace, Mark T.

    2013-01-01

    Multisensory integration has been widely studied in neurons of the mammalian superior colliculus (SC). This has led to the description of various determinants of multisensory integration, including those based on stimulus- and neuron-specific factors. The most widely characterized of these illustrate the importance of the spatial and temporal relationships of the paired stimuli as well as their relative effectiveness in eliciting a response in determining the final integrated output. Although these stimulus-specific factors have generally been considered in isolation (i.e., manipulating stimulus location while holding all other factors constant), they have an intrinsic interdependency that has yet to be fully elucidated. For example, changes in stimulus location will likely also impact both the temporal profile of response and the effectiveness of the stimulus. The importance of better describing this interdependency is further reinforced by the fact that SC neurons have large receptive fields, and that responses at different locations within these receptive fields are far from equivalent. To address these issues, the current study was designed to examine the interdependency between the stimulus factors of space and effectiveness in dictating the multisensory responses of SC neurons. The results show that neuronal responsiveness changes dramatically with changes in stimulus location – highlighting a marked heterogeneity in the spatial receptive fields of SC neurons. More importantly, this receptive field heterogeneity played a major role in the integrative product exhibited by stimulus pairings, such that pairings at weakly responsive locations of the receptive fields resulted in the largest multisensory interactions. Together these results provide greater insight into the interrelationship of the factors underlying multisensory integration in SC neurons, and may have important mechanistic implications for multisensory integration and the role it plays in shaping

  14. Increased functional connectivity between superior colliculus and brain regions implicated in bodily self-consciousness during the rubber hand illusion.

    Science.gov (United States)

    Olivé, Isadora; Tempelmann, Claus; Berthoz, Alain; Heinze, Hans-Joachim

    2015-02-01

    Bodily self-consciousness refers to bodily processes operating at personal, peripersonal, and extrapersonal spatial dimensions. Although the neural underpinnings of representations of personal and peripersonal space associated with bodily self-consciousness were thoroughly investigated, relatively few is known about the neural underpinnings of representations of extrapersonal space relevant for bodily self-consciousness. In the search to unravel brain structures generating a representation of the extrapersonal space relevant for bodily self-consciousness, we developed a functional magnetic resonance imaging (fMRI) study to investigate the implication of the superior colliculus (SC) in bodily illusions, and more specifically in the rubber hand illusion (RHi), which constitutes an established paradigm to study the neural underpinnings of bodily self-consciousness. We observed activation of the colliculus ipsilateral to the manipulated hand associated with eliciting of RHi. A generalized form of context-dependent psychophysiological interaction analysis unravelled increased illusion-dependent functional connectivity between the SC and some of the main brain areas previously involved in bodily self-consciousness: right temporoparietal junction (rTPJ), bilateral ventral premotor cortex (vPM), and bilateral postcentral gyrus. We hypothesize that the collicular map of the extrapersonal space interacts with maps of the peripersonal and personal space generated at rTPJ, vPM and the postcentral gyrus, producing a unified representation of space that is relevant for bodily self-consciousness. We suggest that processes of multisensory integration of bodily-related sensory inputs located in this unified representation of space constitute one main factor underpinning emergence of bodily self-consciousness.

  15. Neurofilament proteins are preferentially expressed in descending output neurons of the cat the superior colliculus: a study using SMI-32.

    Science.gov (United States)

    Fuentes-Santamaria, V; Stein, B E; McHaffie, J G

    2006-01-01

    Physiological studies indicate that the output neurons in the multisensory (i.e. intermediate and deep) laminae of the cat superior colliculus receive converging information from widespread regions of the neuraxis, integrate this information, and then relay the product to regions of the brainstem involved in the control of head and eye movements. Yet, an understanding of the neuroanatomy of these converging afferents has been hampered because many terminals contact distal dendrites that are difficult to label with the neurochemical markers generally used to visualize superior colliculus output neurons. Here we show that the SMI-32 antibody, directed at the non-phosphorylated epitopes of high molecular weight neurofilament proteins, is an effective marker for these superior colliculus output neurons. It is also one that can label their distal dendrites. Superior colliculus sections processed for SMI-32 revealed numerous labeled neurons with varying morphologies within the deep laminae. In contrast, few labeled neurons were observed in the superficial laminae. Neurons with large somata in the lateral aspects of the deep superior colliculus were particularly well labeled, and many of their secondary and tertiary dendrites were clearly visible. Injections of the fluorescent biotinylated dextran amine into the pontine reticular formation revealed that approximately 80% of the SMI-32 immunostained neurons also contained retrogradely transported biotinylated dextran amine, indicating that SMI-32 is a common cytoskeletal component expressed in descending output neurons. Superior colliculus output neurons also are known to express the calcium-binding protein parvalbumin, and many SMI-32 immunostained neurons also proved to be parvalbumin immunostained. These studies suggest that SMI-32 can serve as a useful immunohistochemical marker for detailing the somatic and dendritic morphology of superior colliculus output neurons and for facilitating evaluations of their input

  16. Maturation of multisensory integration in the superior colliculus: expression of nitric oxide synthase and neurofilament SMI-32.

    Science.gov (United States)

    Fuentes-Santamaria, Veronica; McHaffie, John G; Stein, Barry E

    2008-11-25

    Nitric oxide (NO) containing (nitrergic) interneurons are well-positioned to convey the cortical influences that are crucial for multisensory integration in superior colliculus (SC) output neurons. However, it is not known whether nitrergic interneurons are in this position early in life, and might, therefore, also play a role in the functional maturation of this circuit. In the present study, we investigated the postnatal developmental relationship between these two populations of neurons using Beta-nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH) histochemistry and SMI-32 immunocytochemistry to label presumptive interneurons and output neurons, respectively. SMI-32 immunostained neurons were proved to mature and retained immature anatomical features until approximately 8 postnatal weeks. In contrast, nitrergic interneurons developed more rapidly. They had achieved their adult-like anatomy by 4 postnatal weeks and were in a position to influence the dendritic elaboration of output neurons. It is this dendritic substrate through which much of the cortico-collicular influence is expressed. Double-labeling experiments showed that the dendritic and axonal processes of nitrergic interneurons already apposed the somata and dendrites of SMI-32 labeled neurons even at the earliest age examined. The results suggest that nitrergic interneurons play a role in refining the cortico-collicular projection patterns that are believed to be essential for SC output neurons to engage in multisensory integration and to support normal orientation responses to cross-modal stimuli.

  17. Distractor evoked deviations of saccade trajectory are modulated by fixation activity in the superior colliculus: computational and behavioral evidence.

    Directory of Open Access Journals (Sweden)

    Zhiguo Wang

    Full Text Available Previous studies have shown that saccades may deviate towards or away from task irrelevant visual distractors. This observation has been attributed to active suppression (inhibition of the distractor location unfolding over time: early in time inhibition at the distractor location is incomplete causing deviation towards the distractor, while later in time when inhibition is complete the eyes deviate away from the distractor. In a recent computational study, Wang, Kruijne and Theeuwes proposed an alternative theory that the lateral interactions in the superior colliculus (SC, which are characterized by short-distance excitation and long-distance inhibition, are sufficient for generating both deviations towards and away from distractors. In the present study, we performed a meta-analysis of the literature, ran model simulations and conducted two behavioral experiments to further explore this unconventional theory. Confirming predictions generated by the model simulations, the behavioral experiments show that a saccades deviate towards close distractors and away from remote distractors, and b the amount of deviation depends on the strength of fixation activity in the SC, which can be manipulated by turning off the fixation stimulus before or after target onset (Experiment 1, or by varying the eccentricity of the target and distractor (Experiment 2.

  18. Distractor evoked deviations of saccade trajectory are modulated by fixation activity in the superior colliculus: computational and behavioral evidence.

    Science.gov (United States)

    Wang, Zhiguo; Theeuwes, Jan

    2014-01-01

    Previous studies have shown that saccades may deviate towards or away from task irrelevant visual distractors. This observation has been attributed to active suppression (inhibition) of the distractor location unfolding over time: early in time inhibition at the distractor location is incomplete causing deviation towards the distractor, while later in time when inhibition is complete the eyes deviate away from the distractor. In a recent computational study, Wang, Kruijne and Theeuwes proposed an alternative theory that the lateral interactions in the superior colliculus (SC), which are characterized by short-distance excitation and long-distance inhibition, are sufficient for generating both deviations towards and away from distractors. In the present study, we performed a meta-analysis of the literature, ran model simulations and conducted two behavioral experiments to further explore this unconventional theory. Confirming predictions generated by the model simulations, the behavioral experiments show that a) saccades deviate towards close distractors and away from remote distractors, and b) the amount of deviation depends on the strength of fixation activity in the SC, which can be manipulated by turning off the fixation stimulus before or after target onset (Experiment 1), or by varying the eccentricity of the target and distractor (Experiment 2).

  19. Changes in Otx2 and Parvalbumin Immunoreactivity in the Superior Colliculus in the Platelet-Derived Growth Factor Receptor-β Knockout Mice

    Directory of Open Access Journals (Sweden)

    Juanjuan Zhao

    2013-01-01

    Full Text Available The superior colliculus (SC, a relay nucleus in the subcortical visual pathways, is implicated in socioemotional behaviors. Homeoprotein Otx2 and β subunit of receptors of platelet-derived growth factor (PDGFR-β have been suggested to play an important role in development of the visual system and development and maturation of GABAergic neurons. Although PDGFR-β-knockout (KO mice displayed socio-emotional deficits associated with parvalbumin (PV-immunoreactive (IR neurons, their anatomical bases in the SC were unknown. In the present study, Otx2 and PV-immunolabeling in the adult mouse SC were investigated in the PDGFR-β KO mice. Although there were no differences in distribution patterns of Otx2 and PV-IR cells between the wild type and PDGFR-β KO mice, the mean numbers of both of the Otx2- and PV-IR cells were significantly reduced in the PDGFR-β KO mice. Furthermore, average diameters of Otx2- and PV-IR cells were significantly reduced in the PDGFR-β KO mice. These findings suggest that PDGFR-β plays a critical role in the functional development of the SC through its effects on Otx2- and PV-IR cells, provided specific roles of Otx2 protein and PV-IR cells in the development of SC neurons and visual information processing, respectively.

  20. NMDA receptor blockade alters the intracellular distribution of neuronal nitric oxide synthase in the superficial layers of the rat superior colliculus

    Directory of Open Access Journals (Sweden)

    R.E. de Bittencourt-Navarrete

    2009-02-01

    Full Text Available Nitric oxide (NO is a molecular messenger involved in several events of synaptic plasticity in the central nervous system. Ca2+ influx through the N-methyl-D-aspartate receptor (NMDAR triggers the synthesis of NO by activating the enzyme neuronal nitric oxide synthase (nNOS in postsynaptic densities. Therefore, NMDAR and nNOS are part of the intricate scenario of postsynaptic densities. In the present study, we hypothesized that the intracellular distribution of nNOS in the neurons of superior colliculus (SC superficial layers is an NMDAR activity-dependent process. We used osmotic minipumps to promote chronic blockade of the receptors with the pharmacological agent MK-801 in the SC of 7 adult rats. The effective blockade of NMDAR was assessed by changes in the protein level of the immediate early gene NGFI-A, which is a well-known NMDAR activity-dependent expressing transcription factor. Upon chronic infusion of MK-801, a decrease of 47% in the number of cells expressing NGFI-A was observed in the SC of treated animals. Additionally, the filled dendritic extent by the histochemical product of nicotinamide adenine di-nucleotide phosphate diaphorase was reduced by 45% when compared to the contralateral SC of the same animals and by 64% when compared to the SC of control animals. We conclude that the proper intracellular localization of nNOS in the retinorecipient layers of SC depends on NMDAR activation. These results are consistent with the view that the participation of NO in the physiological and plastic events of the central nervous system might be closely related to an NMDAR activity-dependent function.

  1. The Distinct Role of the Amygdala, Superior Colliculus and Pulvinar in Processing of Central and Peripheral Snakes

    Science.gov (United States)

    Almeida, Inês; Soares, Sandra C.; Castelo-Branco, Miguel

    2015-01-01

    Introduction Visual processing of ecologically relevant stimuli involves a central bias for stimuli demanding detailed processing (e.g., faces), whereas peripheral object processing is based on coarse identification. Fast detection of animal shapes holding a significant phylogenetic value, such as snakes, may benefit from peripheral vision. The amygdala together with the pulvinar and the superior colliculus are implicated in an ongoing debate regarding their role in automatic and deliberate spatial processing of threat signals. Methods Here we tested twenty healthy participants in an fMRI task, and investigated the role of spatial demands (the main effect of central vs. peripheral vision) in the processing of fear-relevant ecological features. We controlled for stimulus dependence using true or false snakes; snake shapes or snake faces and for task constraints (implicit or explicit). The main idea justifying this double task is that amygdala and superior colliculus are involved in both automatic and controlled processes. Moreover the explicit/implicit instruction in the task with respect to emotion is not necessarily equivalent to explicit vs. implicit in the sense of endogenous vs. exogenous attention, or controlled vs. automatic processes. Results We found that stimulus-driven processing led to increased amygdala responses specifically to true snake shapes presented in the centre or in the peripheral left hemifield (right hemisphere). Importantly, the superior colliculus showed significantly biased and explicit central responses to snake-related stimuli. Moreover, the pulvinar, which also contains foveal representations, also showed strong central responses, extending the results of a recent single cell pulvinar study in monkeys. Similar hemispheric specialization was found across structures: increased amygdala responses occurred to true snake shapes presented to the right hemisphere, with this pattern being closely followed by the superior colliculus and the

  2. Optic nerve, superior colliculus, visual thalamus, and primary visual cortex of the northern elephant seal (Mirounga angustirostris) and California sea lion (Zalophus californianus).

    Science.gov (United States)

    Turner, Emily C; Sawyer, Eva K; Kaas, Jon H

    2017-02-11

    The northern elephant seal (Mirounga angustirostris) and California sea lion (Zalophus californianus) are members of a diverse clade of carnivorous mammals known as pinnipeds. Pinnipeds are notable for their large, ape-sized brains, yet little is known about their central nervous system. Both the northern elephant seal and California sea lion spend most of their lives at sea, but each also spends time on land to breed and give birth. These unique coastal niches may be reflected in specific evolutionary adaptations to their sensory systems. Here, we report on components of the visual pathway in these two species. We found evidence for two classes of myelinated fibers within the pinniped optic nerve, those with thick myelin sheaths (elephant seal: 9%, sea lion: 7%) and thin myelin sheaths (elephant seal: 91%, sea lion: 93%). In order to investigate the architecture of the lateral geniculate nucleus, superior colliculus, and primary visual cortex, we processed brain sections from seal and sea lion pups for Nissl substance, cytochrome oxidase, and vesicular glutamate transporters. As in other carnivores, the dorsal lateral geniculate nucleus consisted of three main layers, A, A1, and C, while each superior colliculus similarly consisted of seven distinct layers. The sea lion visual cortex is located at the posterior side of cortex between the upper and lower banks of the postlateral sulcus, while the elephant seal visual cortex extends far more anteriorly along the dorsal surface and medial wall. These results are relevant to comparative studies related to the evolution of large brains.

  3. Expression of messenger RNAs for glutamic acid decarboxylase, preprotachykinin, cholecystokinin, somatostatin, proenkephalin and neuropeptide Y in the adult rat superior colliculus.

    Science.gov (United States)

    Harvey, A R; Heavens, R P; Yellachich, L A; Sirinathsinghji, D J

    2001-01-01

    The mammalian superior colliculus is an important subcortical integrator of sensorimotor behaviours. It is multi-layered, each layer containing specific neuronal types and possessing distinct input/output relationships. Here we use in situ hybridisation methods to map the distribution of seven neurotransmitters/neuromodulator systems in adult rat superior colliculus. Coronal sections were probed for preprotachykinin, cholecystokinin, somatostatin, proenkephalin, neuropeptide Y and the enzymes glutamic acid decarboxylase and choline acetyltransferase, markers for GABA and acetylcholine respectively. Cells expressing glutamic acid decarboxylase messenger RNA were the most abundant, the highest density being found in the superficial layers. Many cells containing proprotachykinin messenger RNA were found in stratum zonale and the upper two-thirds of stratum griseum superficiale; cells were also located in deeper tectal laminae, particularly caudomedially. Most cholecystokinin messenger RNA expressing cells were located in the superficial layers with a prominent band in the middle third of stratum griseum superficiale. Cells expressing moderate to high levels of somatostatin messenger RNA formed a dense band in the lower third of stratum griseum superficiale/upper stratum opticum; two less distinct tiers of labelling were seen in deeper layers. These in situ hybridisation data reveal three distinct sub-laminae in rat stratum griseum superficiale. Cells expressing moderate to low levels of proenkephalin messenger RNA were located in lower stratum griseum superficiale/upper stratum opticum and intermediate laminae. A cluster of enkephalinergic cells was located medially in the deep tectal laminae. Expression of neuropeptide Y messenger RNA was relatively low and mostly confined to cells in stratum griseum superficiale and stratum opticum. No choline acetyltransferase messenger RNA was detected. This in situ analysis of seven different neurotransmitters

  4. Resonant cholinergic dynamics in cognitive and motor decision-making:Attention, category learning, and choice in neocortex, superior colliculus, and optic tectum

    Directory of Open Access Journals (Sweden)

    Stephen eGrossberg

    2016-01-01

    Full Text Available Freely behaving organisms need to rapidly calibrate their perceptual, cognitive, and motor decisions based on continuously changing environmental conditions. These plastic changes include sharpening or broadening of cognitive and motor attention and learning to match the behavioral demands that are imposed by changing environmental statistics. This article proposes that a shared circuit design for such flexible decision-making is used in specific cognitive and motor circuits, and that both types of circuits use acetylcholine to modulate choice selectivity. Such task-sensitive control is proposed to control thalamocortical choice of the critical features that are cognitively attended and that are incorporated through learning into prototypes of visual recognition categories. A cholinergically-modulated process of vigilance control determines if a recognition category and its attended features are abstract (low vigilance or concrete (high vigilance. Homologous neural mechanisms of cholinergic modulation are proposed to focus attention and learn a multimodal map within the deeper layers of superior colliculus. This map enables visual, auditory, and planned movement commands to compete for attention, leading to selection of a winning position that controls where the next saccadic eye movement will go. Such map learning may be viewed as a kind of attentive motor category learning. The article hereby explicates a link between attention, learning, and cholinergic modulation during decision making within both cognitive and motor systems. Homologs between the mammalian superior colliculus and the avian optic tectum lead to predictions about how multimodal map learning may occur in the avian brain and how such learning may be modulated by acetycholine.

  5. Resonant Cholinergic Dynamics in Cognitive and Motor Decision-Making: Attention, Category Learning, and Choice in Neocortex, Superior Colliculus, and Optic Tectum.

    Science.gov (United States)

    Grossberg, Stephen; Palma, Jesse; Versace, Massimiliano

    2015-01-01

    Freely behaving organisms need to rapidly calibrate their perceptual, cognitive, and motor decisions based on continuously changing environmental conditions. These plastic changes include sharpening or broadening of cognitive and motor attention and learning to match the behavioral demands that are imposed by changing environmental statistics. This article proposes that a shared circuit design for such flexible decision-making is used in specific cognitive and motor circuits, and that both types of circuits use acetylcholine to modulate choice selectivity. Such task-sensitive control is proposed to control thalamocortical choice of the critical features that are cognitively attended and that are incorporated through learning into prototypes of visual recognition categories. A cholinergically-modulated process of vigilance control determines if a recognition category and its attended features are abstract (low vigilance) or concrete (high vigilance). Homologous neural mechanisms of cholinergic modulation are proposed to focus attention and learn a multimodal map within the deeper layers of superior colliculus. This map enables visual, auditory, and planned movement commands to compete for attention, leading to selection of a winning position that controls where the next saccadic eye movement will go. Such map learning may be viewed as a kind of attentive motor category learning. The article hereby explicates a link between attention, learning, and cholinergic modulation during decision making within both cognitive and motor systems. Homologs between the mammalian superior colliculus and the avian optic tectum lead to predictions about how multimodal map learning may occur in the mammalian and avian brain and how such learning may be modulated by acetycholine.

  6. Dissociation between the panicolytic effect of cannabidiol microinjected into the substantia nigra, pars reticulata, and fear-induced antinociception elicited by bicuculline administration in deep layers of the superior colliculus: The role of CB1-cannabinoid receptor in the ventral mesencephalon.

    Science.gov (United States)

    da Silva, Juliana Almeida; Biagioni, Audrey Francisco; Almada, Rafael Carvalho; de Souza Crippa, José Alexandre; Cecílio Hallak, Jaime Eduardo; Zuardi, Antônio Waldo; Coimbra, Norberto Cysne

    2015-07-05

    Many studies suggest that the substantia nigra, pars reticulata (SNpr), a tegmental mesencephalic structure rich in γ-aminobutyric acid (GABA)- and cannabinoid receptor-containing neurons, is involved in the complex control of defensive responses through the neostriatum-nigral disinhibitory and nigro-tectal inhibitory GABAergic pathways during imminently dangerous situations. The aim of the present work was to investigate the role played by CB1-cannabinoid receptor of GABAergic pathways terminal boutons in the SNpr or of SNpr-endocannabinoid receptor-containing interneurons on the effect of intra-nigral microinjections of cannabidiol in the activity of nigro-tectal inhibitory pathways. GABAA receptor blockade in the deep layers of the superior colliculus (dlSC) elicited vigorous defensive behaviour. This explosive escape behaviour was followed by significant antinociception. Cannabidiol microinjection into the SNpr had a clear anti-aversive effect, decreasing the duration of defensive alertness, the frequency and duration of defensive immobility, and the frequency and duration of explosive escape behaviour, expressed by running and jumps, elicited by transitory GABAergic dysfunction in dlSC. However, the innate fear induced-antinociception was not significantly changed. The blockade of CB1 endocannabinoid receptor in the SNpr decreased the anti-aversive effect of canabidiol based on the frequency and duration of defensive immobility, the frequency of escape expressed by running, and both the frequency and duration of escape expressed by jumps. These findings suggest a CB1 mediated endocannabinoid signalling in cannabidiol modulation of panic-like defensive behaviour, but not of innate fear-induced antinociception evoked by GABAA receptor blockade with bicuculline microinjection into the superior colliculus, with a putative activity in nigro-collicular GABAergic pathways.

  7. Inhibitory projections from the ventral nucleus of the lateral lemniscus and superior paraolivary nucleus create directional selectivity of frequency modulations in the inferior colliculus: A comparison of bats with other mammals

    OpenAIRE

    Pollak, George D.; Gittelman, Joshua X; Li, Na; Xie, Ruili

    2010-01-01

    This review considers four auditory brainstem nuclear groups and shows how studies of both bats and other mammals have provided insights into their response properties and the impact of their convergence in the inferior colliculus (IC). The four groups are octopus cells in the cochlear nucleus, their connections with the ventral nucleus of the lateral lemniscus (VNLL) and the superior paraolivary nucleus (SPON), and the connections of the VNLL and SPON with the IC. The theme is that the respo...

  8. Coding for stimulus velocity by temporal patterning of spike discharges in visual cells of cat superior colliculus.

    Science.gov (United States)

    Mandl, G

    1993-07-01

    Statistical analyses, performed on extracellularly recorded spike trains generated by 69 single motion sensitive visual cells in the intermediate layers of superior colliculi of pretrigeminal cat preparations, revealed that--even in the unstimulated condition (38/69)--most neuronal spike discharge patterns tended to switch between two stochastically distinct states, in the form of rapidly alternating "bursting" (high frequency) and "resting" (low frequency) episodes. The numbers of consecutive interspike intervals within a given state were, as a rule, independent integer-valued random variables with discrete probability distributions, in essential agreement with the semi-Markov model proposed by Ekholm and Hyvärinen [(1970) Biophysical Journal, 10, 773-796]. The introduction of visual stimuli (47/69) moving with velocities of 2-160 deg/sec caused systematic and reproducible changes in the ratio of bursting to resting activities, decreases in overall discharge variability, and increases in signal transinformation flow. Moreover, with one group of stimulated cells (28/47), increasing stimulus velocity caused increasingly precise ("stimulus-forced") synchronization of bursting episodes with specific phases of stimulus movement; while for a smaller group (12/47), stimulus-related alternations between bursting and resting states assumed the form of semi-rhythmical burst discharges within the characteristic 60-80 Hz "gamma oscillation" range ("stimulus-induced" synchronization). For a minority of cells (7/47), switching between bursting and resting states--although characteristically modified by stimulus velocity--remained largely desynchronized with all phases of stimulus transit. It was argued that such temporal patterns of discharge may constitute elements of a candidate "distribution" code for movement detection by the cat visual system.

  9. 5-Hydroxytryptamine2A/2C receptors of nucleus raphe magnus and gigantocellularis/paragigantocellularis pars α reticular nuclei modulate the unconditioned fear-induced antinociception evoked by electrical stimulation of deep layers of the superior colliculus and dorsal periaqueductal grey matter.

    Science.gov (United States)

    de Oliveira, Ricardo; de Oliveira, Rithiele Cristina; Falconi-Sobrinho, Luiz Luciano; da Silva Soares, Raimundo; Coimbra, Norberto Cysne

    2017-01-01

    The electrical stimulation of the dorsolateral columns of the periaquedutal grey matter (dlPAG) or deep layers of the superior colliculus (dlSC) evokes defensive behaviours followed by an antinociceptive response. Monoaminergic brainstem reticular nuclei are suggested to comprise the endogenous pain modulatory system. The aim of the present work was to investigate the role played by 5-HT2 subfamily of serotonergic receptors of the nucleus raphe magnus (NRM) and the gigantocellularis/paragigantocellularis pars α reticular nuclei (Gi/PGiα) in the elaboration of instinctive fear-induced antinociception elicited by electrical stimulation of dlPAG or of dlSC. The nociceptive thresholds were measured by the tail-flick test in Wistar rats. The 5-HT2A/2C-serotonergic receptors antagonist ritanserin was microinjected at different concentrations (0.05, 0.5 and 5.0μg/0.2μL) either in Gi/PGiα or in NRM. The blockade of 5-HT2 receptors in both Gi/PGiα and NRM decreased the innate fear-induced antinociception elicited by electrical stimulation of the dlSC or the dlPAG. These findings indicate that serotonin is involved in the hypo-algesia induced by unconditioned fear-induced behavioural responses and the 5-HT2A/2C-serotonergic receptor subfamily in neurons situated in the Gi/PGiα complex and NRM are critically recruited in pain modulation during the panic-like emotional behaviour.

  10. Inhibitory projections from the ventral nucleus of the lateral lemniscus and superior paraolivary nucleus create directional selectivity of frequency modulations in the inferior colliculus: a comparison of bats with other mammals.

    Science.gov (United States)

    Pollak, George D; Gittelman, Joshua X; Li, Na; Xie, Ruili

    2011-03-01

    This review considers four auditory brainstem nuclear groups and shows how studies of both bats and other mammals have provided insights into their response properties and the impact of their convergence in the inferior colliculus (IC). The four groups are octopus cells in the cochlear nucleus, their connections with the ventral nucleus of the lateral lemniscus (VNLL) and the superior paraolivary nucleus (SPON), and the connections of the VNLL and SPON with the IC. The theme is that the response properties of neurons in the SPON and VNLL map closely onto the synaptic response features of a unique subpopulation of cells in the IC of bats whose inputs are dominated by inhibition. We propose that the convergence of VNLL and SPON inputs generates the tuning of these IC cells, their unique temporal responses to tones, and their directional selectivities for frequency modulated (FM) sweeps. Other IC neurons form directional properties in other ways, showing that selective response properties are formed in multiple ways. In the final section we discuss why multiple formations of common response properties could amplify differences in population activity patterns evoked by signals that have similar spectrotemporal features.

  11. Regulation of self-renewing neural progenitors by FGF/ERK signaling controls formation of the inferior colliculus.

    Science.gov (United States)

    Dee, Alexander; Li, Kairong; Heng, Xin; Guo, Qiuxia; Li, James Y H

    2016-10-15

    The embryonic tectum displays an anteroposterior gradient in development and produces the superior colliculus and inferior colliculus. Studies suggest that partition of the tectum is controlled by different strengths and durations of FGF signals originated from the so-called isthmic organizer at the mid/hindbrain junction; however, the underlying mechanism is unclear. We show that deleting Ptpn11, which links FGF with the ERK pathway, prevents inferior colliculus formation by depleting a previously uncharacterized stem cell zone. The stem-zone loss is attributed to shortening of S phase and acceleration of cell cycle exit and neurogenesis. Expression of a constitutively active Mek1 (Mek1(DD)), the known ERK activator, restores the tectal stem zone and the inferior colliculus without Ptpn11. By contrast, Mek1(DD) expression fails to rescue the tectal stem zone and the inferior colliculus in the absence of Fgf8 and the isthmic organizer, indicating that FGF and Mek1(DD) initiate qualitatively and/or quantitatively distinctive signaling. Together, our data show that the formation of the inferior colliculus relies on the provision of new cells from the tectal stem zone. Furthermore, distinctive ERK signaling mediates Fgf8 in the control of cell survival, tissue polarity and cytogenetic gradient during the development of the tectum.

  12. Satisfação de estudantes formandos em administração de Joinville/SC com o seu curso e com sua instituição de ensino superior: aspectos relacionados ao mercado de trabalho

    Directory of Open Access Journals (Sweden)

    Emerson Wagner Mainardes

    2010-05-01

    Hidden="false" UnhideWhenUsed="false" QFormat="true" Name="Subtle Emphasis" /> SATISFAÇÃO DE ESTUDANTES FORMANDOS EM ADMINISTRAÇÃO DE JOINVILLE/SC COM O SEU CURSO E COM SUA INSTITUIÇÃO DE ENSINO SUPERIOR: ASPECTOS RELACIONADOS AO MERCADO DE TRABALHO

     

    RESUMO

    Em um mercado de ensino superior competitivo, como é o caso do Brasil, oferecer um ensino que satisfaça alunos e mercado de trabalho tem sido fundamental para atrair e reter alunos em uma instituição de ensino superior (IES. Este estudo objetivou determinar a satisfação dos atuais alunos com os aspectos da graduação em administração ligados ao mercado de trabalho nas IES de Joinville, SC. Para a realização do estudo, buscou-se estudos que tratam da satisfação de estudantes, encontrando-se 5 atributos que medem a satisfação com atributos ligados ao

  13. Satisfação de estudantes formandos em administração de Joinville/SC com o seu curso e com sua instituição de ensino superior: aspectos relacionados ao mercado de trabalho [doi: 10.5329/RECADM.20100901004

    Directory of Open Access Journals (Sweden)

    Emerson Wagner Mainardes

    2010-05-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE SATISFAÇÃO DE ESTUDANTES FORMANDOS EM ADMINISTRAÇÃO DE JOINVILLE/SC COM O SEU CURSO E COM SUA INSTITUIÇÃO DE ENSINO SUPERIOR: ASPECTOS RELACIONADOS AO MERCADO DE TRABALHO   RESUMO Em um mercado de ensino superior competitivo, como é o caso do Brasil, oferecer um ensino que satisfaça alunos e mercado de trabalho tem sido fundamental para atrair e reter alunos em uma instituição de ensino superior (IES. Este estudo objetivou determinar a satisfação dos atuais alunos com os aspectos da graduação em administração ligados ao mercado de trabalho nas IES de Joinville, SC. Para a realização do estudo, buscou-se estudos que tratam da satisfação de estudantes, encontrando-se 5 atributos que medem a satisfação com atributos ligados ao mercado de trabalho. Em seguida, realizou-se uma pesquisa quantitativa-descritiva junto aos alunos formandos em duas das cinco IES que oferecem o curso de administração em Joinville, SC. Aplicou-se um questionário estruturado junto a 283 formandos destas duas IES. Com os dados coletados, caracterizou-se estes formandos e identificou-se os atributos de melhor e pior desempenho quanto a satisfação dos alunos nos aspectos ligados ao mercado de trabalho. Encontrou-se também os atributos que mais contribuem para a satisfação dos alunos. Os alunos mostraram-se satisfeitos, e ressaltaram que a imagem da IES no mercado, a empregabilidade e o atendimento às necessidades dos alunos e do mercado de trabalho são essenciais para os estudantes se sentirem satisfeitos com seu curso e sua IES.   Palavras-chave Satisfação de estudantes; mercado de trabalho; formandos em administração; instituições de ensino superior.     SATISFACTION OF GRADUATES IN ADMINISTRATION OF JOINVILLE/SC WITH THE COURSE AND WITH THE HIGHER EDUCATION INSTITUTION: ASPECTS RELATED TO THE JOB MARKET   ABSTRACT In a market of competitive higher education, as it is the case of

  14. S-C Mylonites

    NARCIS (Netherlands)

    Lister, G.S.; Snoke, A.W.

    1984-01-01

    Two types of foliations are commonly developed in mylonites and mylonitic rocks: (a) S-surfaces related to the accumulation of finite strain and (b) C-surfaces related to displacement discontinuities or zones of relatively high shear strain. There are two types of S-C mylonites. Type I S-C mylonites

  15. Antisaccade Performance in Schizophrenia: A Neural Model of Decision Making in the Superior Colliculus

    Directory of Open Access Journals (Sweden)

    Vassilis eCutsuridis

    2014-02-01

    Full Text Available Antisaccade performance deficits in schizophrenia are generally interpreted as an impaired top-down inhibitory signal failing to suppress the erroneous response. We recorded the antisaccade performance (error rates and latencies of healthy and schizophrenia subjects performing the mirror antisaccade task. A neural rise-to-threshold model of antisaccade performance was developed to uncover the biophysical mechanisms giving rise to the observed deficits in schizophrenia. Schizophrenia patients displayed greater variability in the antisaccade and corrected antisaccade latency distributions, increased error rates and decreased corrected errors, relative to healthy participants. Our model showed that i increased variability is due to a more noisy accumulation of information by schizophrenia patients, but their confidence level required before making a decision is unaffected, and ii competition between the correct and erroneous decision processes, and not a third top-down inhibitory signal of the erroneous response, accounts for the antisaccade performance of healthy and schizophrenia subjects. Local competition further ensured that a correct antisaccade is never followed by an error prosaccade.

  16. Monopolar intracochlear pulse trains selectively activate the inferior colliculus.

    Science.gov (United States)

    Schoenecker, Matthew C; Bonham, Ben H; Stakhovskaya, Olga A; Snyder, Russell L; Leake, Patricia A

    2012-10-01

    Previous cochlear implant studies using isolated electrical stimulus pulses in animal models have reported that intracochlear monopolar stimulus configurations elicit broad extents of neuronal activation within the central auditory system-much broader than the activation patterns produced by bipolar electrode pairs or acoustic tones. However, psychophysical and speech reception studies that use sustained pulse trains do not show clear performance differences for monopolar versus bipolar configurations. To test whether monopolar intracochlear stimulation can produce selective activation of the inferior colliculus, we measured activation widths along the tonotopic axis of the inferior colliculus for acoustic tones and 1,000-pulse/s electrical pulse trains in guinea pigs and cats. Electrical pulse trains were presented using an array of 6-12 stimulating electrodes distributed longitudinally on a space-filling silicone carrier positioned in the scala tympani of the cochlea. We found that for monopolar, bipolar, and acoustic stimuli, activation widths were significantly narrower for sustained responses than for the transient response to the stimulus onset. Furthermore, monopolar and bipolar stimuli elicited similar activation widths when compared at stimulus levels that produced similar peak spike rates. Surprisingly, we found that in guinea pigs, monopolar and bipolar stimuli produced narrower sustained activation than 60 dB sound pressure level acoustic tones when compared at stimulus levels that produced similar peak spike rates. Therefore, we conclude that intracochlear electrical stimulation using monopolar pulse trains can produce activation patterns that are at least as selective as bipolar or acoustic stimulation.

  17. Human inferior colliculus activity relates to individual differences in spoken language learning.

    Science.gov (United States)

    Chandrasekaran, Bharath; Kraus, Nina; Wong, Patrick C M

    2012-03-01

    A challenge to learning words of a foreign language is encoding nonnative phonemes, a process typically attributed to cortical circuitry. Using multimodal imaging methods [functional magnetic resonance imaging-adaptation (fMRI-A) and auditory brain stem responses (ABR)], we examined the extent to which pretraining pitch encoding in the inferior colliculus (IC), a primary midbrain structure, related to individual variability in learning to successfully use nonnative pitch patterns to distinguish words in American English-speaking adults. fMRI-A indexed the efficiency of pitch representation localized to the IC, whereas ABR quantified midbrain pitch-related activity with millisecond precision. In line with neural "sharpening" models, we found that efficient IC pitch pattern representation (indexed by fMRI) related to superior neural representation of pitch patterns (indexed by ABR), and consequently more successful word learning following sound-to-meaning training. Our results establish a critical role for the IC in speech-sound representation, consistent with the established role for the IC in the representation of communication signals in other animal models.

  18. Study of the inferior colliculus in patients with schizophrenia by magnetic resonance spectroscopy.

    Science.gov (United States)

    Martinez-Granados, B; Martinez-Bisbal, M C; Sanjuan, J; Aguilar, E J; Marti-Bonmati, L; Molla, E; Celda, B

    2014-07-01

    INTRODUCTION. Previous studies have suggested morphometric and functional abnormalities in the inferior colliculus in patients with schizophrenia. Auditory hallucinations are one of the central symptoms in schizophrenia. In this complex and multidimensional event both attention and emotion are thought to play a key role. AIM. To study metabolic changes in the inferior colliculus, a nucleus integrated in the auditory pathway, in patients with schizophrenia and the possible relationship with auditory hallucinations. SUBJECTS AND METHODS. Magnetic resonance spectroscopic imaging studies were performed in 30 right-handed patients with chronic schizophrenia (19 of them with auditory hallucinations) and 28 controls. A magnetic resonance spectroscopic imaging 2D slice was acquired and the voxels representative of both inferior colliculi were selected. N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) peak areas were measured. RESULTS. The patients with schizophrenia showed a NAA/Cr significant reduction in the right inferior colliculus compared to the control subjects. The metabolic data in the right inferior colliculus were correlated with emotional auditory hallucinations items. CONCLUSIONS. The contribution of the inferior colliculus on neural underpinnings of auditory hallucinations is particularly relevant for the right inferior colliculus and is centered on attention-emotional component of this symptom.

  19. Linear processing of interaural level difference underlies spatial tuning in the nucleus of the brachium of the inferior colliculus.

    Science.gov (United States)

    Slee, Sean J; Young, Eric D

    2013-02-27

    The spatial location of sounds is an important aspect of auditory perception, but the ways in which space is represented are not fully understood. No space map has been found within the primary auditory pathway. However, a space map has been found in the nucleus of the brachium of the inferior colliculus (BIN), which provides a major auditory projection to the superior colliculus. We measured the spectral processing underlying auditory spatial tuning in the BIN of unanesthetized marmoset monkeys. Because neurons in the BIN respond poorly to tones and are broadly tuned, we used a broadband stimulus with random spectral shapes (RSSs) from which both spatial receptive fields and frequency sensitivity can be derived. Responses to virtual space (VS) stimuli, based on the animal's own ear acoustics, were compared with the predictions of a weight-function model of responses to the RSS stimuli. First-order (linear) weight functions had broad spectral tuning (approximately three octaves) and were excitatory in the contralateral ear, inhibitory in the ipsilateral ear, and biased toward high frequencies. Responses to interaural time differences and spectral cues were relatively weak. In cross-validation tests, the first-order RSS model accurately predicted the measured VS tuning curves in the majority of neurons, but was inaccurate in 25% of neurons. In some cases, second-order weighting functions led to significant improvements. Finally, we found a significant correlation between the degree of binaural weight asymmetry and the best azimuth. Overall, the results suggest that linear processing of interaural level difference underlies spatial tuning in the BIN.

  20. SC tuning fork

    CERN Multimedia

    The tuning fork used to modulate the radiofrequency system of the synchro cyclotron (SC) from 1957 to 1973. This piece is an unused spare part. The SC was the 1st accelerator built at CERN. It operated from August 1957 until it was closed down at the end of 1990. In the SC the magnetic field did not change with time, and the particles were accelerated in successive pulses by a radiofrequency voltage of some 20kV which varied in frequency as they spiraled outwards towards the extraction radius. The frequency varied from 30MHz to about 17Mz in each pulse. The tuning fork vibrated at 55MHz in vacuum in an enclosure which formed a variable capacitor in the tuning circuit of the RF system, allowing the RF to vary over the appropriate range to accelerate protons from the centre of the macine up to 600Mev at extraction radius. In operation the tips of the tuning fork blade had an amplitude of movement of over 1 cm. The SC accelerator underwent extensive improvements from 1973 to 1975, including the installation of a...

  1. SC2 dee

    CERN Multimedia

    1974-01-01

    Checking the positioning of the dee before its introduction into the vacuum chamber of SC2. The dee is mounted on a large cover plate which also carries the dee liner and the pump manifold. The dummy dee is fixed to the pole faces within the vacuum chamber.

  2. Circuits for Processing Dynamic Interaural Intensity Disparities in the Inferior Colliculus

    Science.gov (United States)

    Pollak, George D.

    2013-01-01

    Interaural intensity disparities (IIDs), the cues all animals use to localize high frequency sounds, are initially processed in the lateral superior olive (LSO) by a subtractive process where inputs from one ear excite and inputs from the other ear inhibit LSO neurons. Such cells are called excitatory-inhibitory (EI) neurons and are prominent not only in the LSO but also in higher nuclei, which include the dorsal nucleus of the lateral lemniscus (DNLL) and inferior colliculus (IC). The IC is of particular interest since its EI cells receive diverse innervation patterns from a large number of lower nuclei, which include the DNLLs and LSOs, and thus comprise a population with diverse binaural properties. The first part of this review focuses on the circuits that create EI cells in the LSO, DNLL and IC. The second section then turns to the responses evoked by dynamic IIDs that change over time, as with multiple sounds that emanate from different regions of space or moving sound sources. I show that many EI neurons in the IC respond to dynamic IIDs in ways that are not predictable from their responses to static IIDs, IIDs presented one at a time. In the final section, results from in vivo whole cell recording in the IC are presented and address the connectional basis for the responsiveness to dynamic IIDs. The principal conclusion is that EI cells comprise a diverse population. The diversity is created by the particular set of inputs each EI type receives and is expressed in the differences in the responses to dynamic IIDs that are generated by those inputs. These results show that the construction of EI neurons in the IC imparts features that not only encode the location of an individual sound source, but also that allow animals to determine the direction of a moving sound and to focus and localize a single sound in midst of many sounds, as typically occurs in the daily lives of all animals. PMID:22343068

  3. PERIPHERAL HEARING LOSS CAUSES HYPEREXCITABILITY OF THE INFERIOR COLLICULUS

    Institute of Scientific and Technical Information of China (English)

    Sun Wei

    2013-01-01

    Growing evidence has been found to suggest that early development of the central auditory system is dependent on acoustic stimuli. Peripheral damage caused by noise exposure and ototoxic drugs can induce functional and anatomical changes along the auditory pathways. The inferior colliculus (IC) is a unique structure in the auditory system located between the primary auditory nuclei of the brainstem and the thala-mus. Damage to the IC inhibitory circuitry may affect central auditory processing and sound perception. Here, we review some of the striking electrophysiological changes in the IC that occur after noise exposure and ototoxic drug treatment. A common occurrence that emerges in the IC after peripheral damage is hyper-excitability of sound-evoked response. The hyperexcitability of the IC is likely related with reduced inhibi-tory response that requires normal peripheral inputs. Early age hearing loss can result in a long lasting in-creased susceptibility to audiogenic seizure which is related to hyperactivity in the IC evoked by loud sounds. Our studies suggest that hearing loss can cause increased IC neuron responsiveness which may be related to tinnitus, hyperacusis, and audiogenic seizure.

  4. Colliculus atlantis: an insufficiently considered anatomic structure in open-mouth radiography of the cervical spine; Der Colliculus atlantis - eine wenig beachtete anatomische Struktur - im transoralen Roentgenbild der Halswirbelsaeule

    Energy Technology Data Exchange (ETDEWEB)

    Schmidberger, H.R. [Universitaetsklinik fuer Radiologie, Graz (Austria); Weiglein, A.H. [Graz Univ. (Austria). Anatomisches Inst.

    1998-12-01

    Purpose: To study the time and mode of the development of the colliculus atlantis, the rate of its occurrence, the causes for its absence, and the radiological-clinical importance in the analysis of open-mouth-view radiographs. Material and Methods: Retrospective analysis of standardized radiographs of the cervical spine in more than 20 000 adults and 100 children. Study of 234 human skeletons of different ages and of 38 isolated adult atlases. Cadaveric dissection of 42 adults (age 48-87). Axial radiographs of isolated atlases and analysis of the bony structures of the colliculus atlantis. Results: The colliculus atlantis develops between age 10 and 13 years. It is always present after age 13 years. For the development of the colliculus atlantis a normal function of the craniocervical joints is necessary. In congenital dysmorphias of the craniocervical region with dysfunction of the craniocervical joints and in fractures of the dens axis before age 10 years with instable healing the colliculus atlantis is absent. Conclusions: The colliculus atlantis is developed at age 13 years apart from some rare exceptions as mentioned. Changes of the site and the structure of the colliculus atlantis allow an early diagnosis of certain traumatically and inflammatory diseases of this region. Furthermore, it serves as an additional parameter in functional analysis of the craniocervical joints. (orig.) [Deutsch] Ziel: Untersuchungen ueber den Zeitpunkt und die Art der Entstehung des Colliculus atlantis, die Haeufigkeit des Vorkommens, die Ursachen seines Fehlens und seine radiologisch-klinische Bedeutung bei der Analyse transoraler Roentgenaufnahmen. Methode: Retrospektive Analyse streng standardisierter Roentgenaufnahmen der Halswirbelsaeule von mehr als 20 000 Erwachsenen und 100 Kindern. Untersuchungen von 234 menschlichen Skeletten verschiedenen Alters und 38 isolierten Atlanten von Erwachsenen. Frische Sektionen von 42 Erwachsenen (48-87 Jahre). Axiale Roentgenaufnahmen

  5. Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, Milla; Lehtonen, Liisa; Lapinleimu, Helena [Turku University Central Hospital, Department of Paediatrics, Turku (Finland); Parkkola, Riitta [Turku University Central Hospital, Department of Radiology and Turku PET Centre, Turku (Finland); Johansson, Reijo [Turku University Central Hospital, Department of Otorhinolaryngology, Turku (Finland); Jaeaeskelaeinen, Satu K. [Turku University Central Hospital, Department of Clinical Neurophysiology, Turku (Finland); Kujari, Harry [Turku University Central Hospital, Department of Pathology, Turku (Finland); Haataja, Leena [Turku University Central Hospital, Department of Paediatric Neurology, Turku (Finland)

    2009-08-15

    Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants. (orig.)

  6. Intracellular responses to frequency modulated tones in the dorsal cortex of the mouse inferior colliculus

    NARCIS (Netherlands)

    H.R.A.P. Geis (H.-Rüdiger A.P.); J.G.G. Borst (Gerard)

    2013-01-01

    textabstractFrequency modulations occur in many natural sounds, including vocalizations. The neuronal response to frequency modulated (FM) stimuli has been studied extensively in different brain areas, with an emphasis on the auditory cortex and the central nucleus of the inferior colliculus. Here,

  7. HISTOLOGICAL STUDIES OF THE EFFECTS OF MONOSODIUM GLUTAMATE ON THE INFERIOR COLLICULUS OF ADULT WISTAR RATS.

    Directory of Open Access Journals (Sweden)

    A.O. Eweka.

    2008-01-01

    Full Text Available Histological effects of Monosodium glutamate (MSG commonly used as food additive on the inferior colliculus (IC of adult Wistar rats were carefully studied. The rats of both sexes (n=24, average weight of 185g were randomly assigned into two treatments (n=16 and control (n=8 groups. The rats in the treatment groups received 3g and 6g of MSG thoroughly mixed with their feeds for fourteen days, while the control rats received equal amounts of feeds without MSG added. The rats were fed with growers' mash purchased from Edo Feeds and Flour Mill Ltd, Ewu, Edo State and were given water liberally. The rats were sacrificed on day fifteen of the experiment. The inferior colliculus was carefully dissected out and quickly fixed in 10% formal saline for routine histological study after H&E method.The histological findings after H&E methods indicated that the treated sections of the inferior colliculus showed some cellular degenerative changes, cellular hypertrophy, and autophagic vacuoles with some intercellular vacuolations appearing in the stroma, and some degree of neuronal hypertrophy when compared to the control sections.These findings indicate that MSG consumption may have a deleterious effect on the neurons of the inferior colliculus (IC. MSG may probably have adverse effects on the auditory sensibilities by its deleterious effects on the nerve cells of the IC of adult Wistar rats. It is recommended that further studies aimed at corroborating these observations be carried out.

  8. LOCAL COLLISION SIMULATION OF AN SC WALL USING ENERGY ABSORBING STEEL

    Directory of Open Access Journals (Sweden)

    CHUL-HUN CHUNG

    2013-08-01

    Full Text Available This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.

  9. Limited segregation of different types of sound localization information among classes of units in the inferior colliculus.

    Science.gov (United States)

    Chase, Steven M; Young, Eric D

    2005-08-17

    The auditory system uses three cues to decode sound location: interaural time differences (ITDs), interaural level differences (ILDs), and spectral notches (SNs). Initial processing of these cues is done in separate brainstem nuclei, with ITDs in the medial superior olive, ILDs in the lateral superior olive, and SNs in the dorsal cochlear nucleus. This work addresses the nature of the convergence of localization information in the central nucleus of the inferior colliculus (ICC). Ramachandran et al. (1999) argued that ICC neurons of types V, I, and O, respectively, receive their predominant inputs from ITD-, ILD-, and SN-sensitive brainstem nuclei, suggesting that these ICC response types should be differentially sensitive to localization cues. Here, single-unit responses to simultaneous manipulation of pairs of localization cues were recorded, and the mutual information between discharge rate and individual cues was quantified. Although rate responses to cue variation were generally consistent with those expected from the hypothesized anatomical connections, the differences in information were not as large as expected. Type I units provide the most information, especially about SNs in the physiologically useful range. Type I and O units provide information about ILDs, even at low frequencies at which actual ILDs are very small. ITD information is provided by a subset of all low-frequency neurons. Type V neurons provide information mainly about ITDs and the average binaural intensity. These results are the first to quantify the relative representation of cues in terms of information and suggest a variety of degrees of cue integration in the ICC.

  10. Responses from two firing patterns in inferior colliculus neurons to stimulation of the lateral lemniscus dorsal nucleus

    Science.gov (United States)

    Li, Xiao-ting; Wang, Ning-yu; Wang, Yan-jun; Xu, Zhi-qing; Liu, Jin-feng; Bai, Yun-fei; Dai, Jin-sheng; Zhao, Jing-yi

    2016-01-01

    The γ-aminobutyric acid neurons (GABAergic neurons) in the inferior colliculus are classified into various patterns based on their intrinsic electrical properties to a constant current injection. Although this classification is associated with physiological function, the exact role for neurons with various firing patterns in acoustic processing remains poorly understood. In the present study, we analyzed characteristics of inferior colliculus neurons in vitro, and recorded responses to stimulation of the dorsal nucleus of the lateral lemniscus using the whole-cell patch clamp technique. Seven inferior colliculus neurons were tested and were classified into two firing patterns: sustained-regular (n = 4) and sustained-adapting firing patterns (n = 3). The majority of inferior colliculus neurons exhibited slight changes in response to stimulation and bicuculline. The responses of one neuron with a sustained-adapting firing pattern were suppressed after stimulation, but recovered to normal levels following application of the γ-aminobutyric acid receptor antagonist. One neuron with a sustained-regular pattern showed suppressed stimulation responses, which were not affected by bicuculline. Results suggest that GABAergic neurons in the inferior colliculus exhibit sustained-regular or sustained-adapting firing patterns. Additionally, GABAergic projections from the dorsal nucleus of the lateral lemniscus to the inferior colliculus are associated with sound localization. The different neuronal responses of various firing patterns suggest a role in sound localization. A better understanding of these mechanisms and functions will provide better clinical treatment paradigms for hearing deficiencies. PMID:27335563

  11. Responses from two firing patterns in inferior colliculus neurons to stimulation of the lateral lemniscus dorsal nucleus

    Directory of Open Access Journals (Sweden)

    Xiao-ting Li

    2016-01-01

    Full Text Available The γ-aminobutyric acid neurons (GABAergic neurons in the inferior colliculus are classified into various patterns based on their intrinsic electrical properties to a constant current injection. Although this classification is associated with physiological function, the exact role for neurons with various firing patterns in acoustic processing remains poorly understood. In the present study, we analyzed characteristics of inferior colliculus neurons in vitro, and recorded responses to stimulation of the dorsal nucleus of the lateral lemniscus using the whole-cell patch clamp technique. Seven inferior colliculus neurons were tested and were classified into two firing patterns: sustained-regular (n = 4 and sustained-adapting firing patterns (n = 3. The majority of inferior colliculus neurons exhibited slight changes in response to stimulation and bicuculline. The responses of one neuron with a sustained-adapting firing pattern were suppressed after stimulation, but recovered to normal levels following application of the γ-aminobutyric acid receptor antagonist. One neuron with a sustained-regular pattern showed suppressed stimulation responses, which were not affected by bicuculline. Results suggest that GABAergic neurons in the inferior colliculus exhibit sustained-regular or sustained-adapting firing patterns. Additionally, GABAergic projections from the dorsal nucleus of the lateral lemniscus to the inferior colliculus are associated with sound localization. The different neuronal responses of various firing patterns suggest a role in sound localization. A better understanding of these mechanisms and functions will provide better clinical treatment paradigms for hearing deficiencies.

  12. Responses from two ifring patterns in inferior colliculus neurons to stimulation of the lateral lemniscus dorsal nucleus

    Institute of Scientific and Technical Information of China (English)

    Xiao-ting Li; Ning-yu Wang; Yan-jun Wang; Zhi-qing Xu; Jin-feng Liu; Yun-fei Bai; Jin-sheng Dai; Jing-yi Zhao

    2016-01-01

    Theγ-aminobutyric acid neurons (GABAergic neurons) in the inferior colliculus are classiifed into various patterns based on their intrin-sic electrical properties to a constant current injection. Although this classiifcation is associated with physiological function, the exact role for neurons with various ifring patterns in acoustic processing remains poorly understood. In the present study, we analyzed characteristics of inferior colliculus neuronsin vitro, and recorded responses to stimulation of the dorsal nucleus of the lateral lemniscus using the whole-cell patch clamp technique. Seven inferior colliculus neurons were tested and were classiifed into two ifring patterns: sustained-regular (n = 4) and sustained-adapting ifring patterns (n = 3). The majority of inferior colliculus neurons exhibited slight changes in response to stimulation and bicuculline. The responses of one neuron with a sustained-adapting ifring pattern were suppressed after stimulation, but recovered to normal levels following application of theγ-aminobutyric acid receptor antagonist. One neuron with a sustained-regular pattern showed suppressed stimulation responses, which were not affected by bicuculline. Results suggest that GABAergic neurons in the inferior colliculus exhibit sustained-regular or sustained-adapting ifring patterns. Additionally, GABAergic projections from the dorsal nu-cleus of the lateral lemniscus to the inferior colliculus are associated with sound localization. The different neuronal responses of various ifring patterns suggest a role in sound localization. A better understanding of these mechanisms and functions will provide better clinical treatment paradigms for hearing deifciencies.

  13. Local inhibition of GABA affects precedence effect in the inferior colliculus

    Institute of Scientific and Technical Information of China (English)

    Yanjun Wang; Ningyu Wang; Dan Wang; Jun Jia; Jinfeng Liu; Yan Xie; Xiaohui Wen; Xiaoting Li

    2014-01-01

    The precedence effect is a prerequisite for faithful sound localization in a complex auditory envi-ronment, and is a physiological phenomenon in which the auditory system selectively suppresses the directional information from echoes. Here we investigated how neurons in the inferior col-liculus respond to the paired sounds that produce precedence-effect illusions, and whether their ifring behavior can be modulated through inhibition with gamma-aminobutyric acid (GABA). We recorded extracellularly from 36 neurons in rat inferior colliculus under three conditions:no injection, injection with saline, and injection with gamma-aminobutyric acid. The paired sounds that produced precedence effects were two identical 4-ms noise bursts, which were deliv-ered contralaterally or ipsilaterally to the recording site. The normalized neural responses were measured as a function of different inter-stimulus delays and half-maximal interstimulus delays were acquired. Neuronal responses to the lagging sounds were weak when the inter-stimulus delay was short, but increased gradually as the delay was lengthened. Saline injection produced no changes in neural responses, but after local gamma-aminobutyric acid application, responses to the lagging stimulus were suppressed. Application of gamma-aminobutyric acid affected the normalized response to lagging sounds, independently of whether they or the paired sounds were contralateral or ipsilateral to the recording site. These observations suggest that local inhibition by gamma-aminobutyric acid in the rat inferior colliculus shapes the neural responses to lagging sounds, and modulates the precedence effect.

  14. Monitor of SC beam profiles

    CERN Multimedia

    1977-01-01

    A high-resolution secondary emission grid for the measurement of SC beam profiles. Modern techniques of metal-ceramic bonding, developed for micro-electronics, have been used in its construction. (See Annual Report 1977 p. 105 Fig. 12.)

  15. First coil for the SC

    CERN Multimedia

    CERN PhotoLab

    1955-01-01

    The coils for the SC magnet were stored in the large hangar of the Cointrin Airport (to make sure that they would be available before snow and ice would block the roads and canals from Belgium, where they were built).

  16. Stimulation of the Lateral Geniculate, Superior Colliculus, or Visual Cortex is Sufficient for Eyeblink Conditioning in Rats

    Science.gov (United States)

    Halverson, Hunter E.; Hubbard, Erin M.; Freeman, John H.

    2009-01-01

    The role of the cerebellum in eyeblink conditioning is well established. Less work has been done to identify the necessary conditioned stimulus (CS) pathways that project sensory information to the cerebellum. A possible visual CS pathway has been hypothesized that consists of parallel inputs to the pontine nuclei from the lateral geniculate…

  17. Fast Detector/First Responder: Interactions between the Superior Colliculus-Pulvinar Pathway and Stimuli Relevant to Primates

    Science.gov (United States)

    Soares, Sandra C.; Maior, Rafael S.; Isbell, Lynne A.; Tomaz, Carlos; Nishijo, Hisao

    2017-01-01

    Primates are distinguished from other mammals by their heavy reliance on the visual sense, which occurred as a result of natural selection continually favoring those individuals whose visual systems were more responsive to challenges in the natural world. Here we describe two independent but also interrelated visual systems, one cortical and the other subcortical, both of which have been modified and expanded in primates for different functions. Available evidence suggests that while the cortical visual system mainly functions to give primates the ability to assess and adjust to fluid social and ecological environments, the subcortical visual system appears to function as a rapid detector and first responder when time is of the essence, i.e., when survival requires very quick action. We focus here on the subcortical visual system with a review of behavioral and neurophysiological evidence that demonstrates its sensitivity to particular, often emotionally charged, ecological and social stimuli, i.e., snakes and fearful and aggressive facial expressions in conspecifics. We also review the literature on subcortical involvement during another, less emotional, situation that requires rapid detection and response—visually guided reaching and grasping during locomotion—to further emphasize our argument that the subcortical visual system evolved as a rapid detector/first responder, a function that remains in place today. Finally, we argue that investigating deficits in this subcortical system may provide greater understanding of Parkinson's disease and Autism Spectrum disorders (ASD). PMID:28261046

  18. Distractor Evoked Deviations of Saccade Trajectory Are Modulated by Fixation Activity in the Superior Colliculus: Computational and Behavioral Evidence

    OpenAIRE

    Zhiguo Wang; Jan Theeuwes

    2014-01-01

    Previous studies have shown that saccades may deviate towards or away from task irrelevant visual distractors. This observation has been attributed to active suppression (inhibition) of the distractor location unfolding over time: early in time inhibition at the distractor location is incomplete causing deviation towards the distractor, while later in time when inhibition is complete the eyes deviate away from the distractor. In a recent computational study, Wang, Kruijne and Theeuwes propose...

  19. Fast Detector/First Responder: Interactions between the Superior Colliculus-Pulvinar Pathway and Stimuli Relevant to Primates.

    Science.gov (United States)

    Soares, Sandra C; Maior, Rafael S; Isbell, Lynne A; Tomaz, Carlos; Nishijo, Hisao

    2017-01-01

    Primates are distinguished from other mammals by their heavy reliance on the visual sense, which occurred as a result of natural selection continually favoring those individuals whose visual systems were more responsive to challenges in the natural world. Here we describe two independent but also interrelated visual systems, one cortical and the other subcortical, both of which have been modified and expanded in primates for different functions. Available evidence suggests that while the cortical visual system mainly functions to give primates the ability to assess and adjust to fluid social and ecological environments, the subcortical visual system appears to function as a rapid detector and first responder when time is of the essence, i.e., when survival requires very quick action. We focus here on the subcortical visual system with a review of behavioral and neurophysiological evidence that demonstrates its sensitivity to particular, often emotionally charged, ecological and social stimuli, i.e., snakes and fearful and aggressive facial expressions in conspecifics. We also review the literature on subcortical involvement during another, less emotional, situation that requires rapid detection and response-visually guided reaching and grasping during locomotion-to further emphasize our argument that the subcortical visual system evolved as a rapid detector/first responder, a function that remains in place today. Finally, we argue that investigating deficits in this subcortical system may provide greater understanding of Parkinson's disease and Autism Spectrum disorders (ASD).

  20. Transmissibility studies of vacuolar changes in the rostral colliculus of pigs

    Directory of Open Access Journals (Sweden)

    Spencer Yvonne I

    2009-09-01

    Full Text Available Abstract Background Histopathological examinations of brains from healthy pigs have revealed localised vacuolar changes, predominantly in the rostral colliculus, that are similar to the neuropil vacuolation featured in the transmissible spongiform encephalopathies and have been described in pigs challenged parenterally with the agent causing bovine spongiform encephalopathy (BSE. Feedstuff containing BSE-contaminated meat and bone meal (MBM may have been fed to pigs prior to the ban of mammalian MBM in feed of farmed livestock in the United Kingdom in 1996, but there is no evidence of the natural occurrence of a transmissible spongiform encephalopathy (TSE in the domestic pig. Furthermore, experimental transmission of BSE to pigs by the oral route has been unsuccessful. A study was conducted to investigate whether the localised vacuolar changes in the porcine brain were associated with a transmissible aetiology and therefore biologically significant. Two groups of ten pigs were inoculated parenterally with vacuolated rostral colliculus from healthy pigs either born before 1996 or born after 1996. Controls included ten pigs similarly inoculated with rostral colliculus from New Zealand-derived pigs and nine pigs inoculated with a bovine BSE brain homogenate. Results None of the pigs inoculated with rostral colliculus developed a TSE-like neurological disease up to five years post inoculation when the study was terminated, and disease-associated prion protein, PrPd, was not detected in the brains of these pigs. By contrast, eight of nine BSE-inoculated pigs developed neurological signs, two of which had detectable PrPd by postmortem tests. No significant histopathological changes were detected to account for the clinical signs in the PrPd-negative, BSE-inoculated pigs. Conclusion The findings in this study suggest that vacuolation in the porcine rostral colliculus is not caused by a transmissible agent and is probably a clinically insignificant

  1. Dual sensitivity of inferior colliculus neurons to ITD in the envelopes of high-frequency sounds: experimental and modeling study

    Science.gov (United States)

    Wang, Le; Devore, Sasha; Delgutte, Bertrand

    2013-01-01

    Human listeners are sensitive to interaural time differences (ITDs) in the envelopes of sounds, which can serve as a cue for sound localization. Many high-frequency neurons in the mammalian inferior colliculus (IC) are sensitive to envelope-ITDs of sinusoidally amplitude-modulated (SAM) sounds. Typically, envelope-ITD-sensitive IC neurons exhibit either peak-type sensitivity, discharging maximally at the same delay across frequencies, or trough-type sensitivity, discharging minimally at the same delay across frequencies, consistent with responses observed at the primary site of binaural interaction in the medial and lateral superior olives (MSO and LSO), respectively. However, some high-frequency IC neurons exhibit dual types of envelope-ITD sensitivity in their responses to SAM tones, that is, they exhibit peak-type sensitivity at some modulation frequencies and trough-type sensitivity at other frequencies. Here we show that high-frequency IC neurons in the unanesthetized rabbit can also exhibit dual types of envelope-ITD sensitivity in their responses to SAM noise. Such complex responses to SAM stimuli could be achieved by convergent inputs from MSO and LSO onto single IC neurons. We test this hypothesis by implementing a physiologically explicit, computational model of the binaural pathway. Specifically, we examined envelope-ITD sensitivity of a simple model IC neuron that receives convergent inputs from MSO and LSO model neurons. We show that dual envelope-ITD sensitivity emerges in the IC when convergent MSO and LSO inputs are differentially tuned for modulation frequency. PMID:24155013

  2. Binaural electric-acoustic interactions recorded from the inferior colliculus of Guinea pigs: the effect of masking observed in the central nucleus of the inferior colliculus.

    Science.gov (United States)

    Noh, Heil; Lee, Dong-Hee

    2012-09-01

    To investigate the electric-acoustic interactions within the inferior colliculus of guinea pigs and to observe how central masking appears in invasive neural recordings of the inferior colliculus (IC). A platinum-iridium wire was inserted to scala tympani through cochleostomy with a depth no greater than 1 mm for intracochlear stimulation of electric pulse train. A 5 mm 100 µm, single-shank, thin-film, penetrating recording probe was inserted perpendicularly to the surface of the IC in the coronal plane at an angle of 30-40° off the parasagittal plane with a depth of 2.0-2.5 mm. The peripheral and central masking effects were compared using electric pulse trains to the left ear and acoustic noise to the left ear (ipsilateral) and to the right ear (contralateral). Binaural acoustic stimuli were presented with different time delays and compared with combined electric and acoustic stimuli. The averaged evoked potentials and total spike numbers were measured using thin-film electrodes inserted into the central nucleus of the IC. Ipsilateral noise had more obvious effects on the electric response than did contralateral noise. Contralateral noise decreased slightly the response amplitude to the electric pulse train stimuli. Immediately after the onset of acoustic noise, the response pattern changed transiently with shorter response intervals. The effects of contralateral noise were evident at the beginning of the continuous noise. The total spike number decreased when the binaural stimuli reached the IC most simultaneously. These results suggest that central masking is quite different from peripheral masking and occurs within the binaural auditory system, and this study showed that the effect of masking could be observed in the IC recording. These effects are more evident and consistent with the psychophysical data from spike number analyses than with the previously reported gross potential data.

  3. Signaled two-way avoidance learning using electrical stimulation of the inferior colliculus as negative reinforcement: effects of visual and auditory cues as warning stimuli

    Directory of Open Access Journals (Sweden)

    A.C. Troncoso

    1998-03-01

    Full Text Available The inferior colliculus is a primary relay for the processing of auditory information in the brainstem. The inferior colliculus is also part of the so-called brain aversion system as animals learn to switch off the electrical stimulation of this structure. The purpose of the present study was to determine whether associative learning occurs between aversion induced by electrical stimulation of the inferior colliculus and visual and auditory warning stimuli. Rats implanted with electrodes into the central nucleus of the inferior colliculus were placed inside an open-field and thresholds for the escape response to electrical stimulation of the inferior colliculus were determined. The rats were then placed inside a shuttle-box and submitted to a two-way avoidance paradigm. Electrical stimulation of the inferior colliculus at the escape threshold (98.12 ± 6.15 (A, peak-to-peak was used as negative reinforcement and light or tone as the warning stimulus. Each session consisted of 50 trials and was divided into two segments of 25 trials in order to determine the learning rate of the animals during the sessions. The rats learned to avoid the inferior colliculus stimulation when light was used as the warning stimulus (13.25 ± 0.60 s and 8.63 ± 0.93 s for latencies and 12.5 ± 2.04 and 19.62 ± 1.65 for frequencies in the first and second halves of the sessions, respectively, P0.05 in both cases. Taken together, the present results suggest that rats learn to avoid the inferior colliculus stimulation when light is used as the warning stimulus. However, this learning process does not occur when the neutral stimulus used is an acoustic one. Electrical stimulation of the inferior colliculus may disturb the signal transmission of the stimulus to be conditioned from the inferior colliculus to higher brain structures such as amygdala

  4. Adaptive adjustment of connectivity in the inferior colliculus revealed by focal pharmacological inactivation.

    Science.gov (United States)

    Gold, J I; Knudsen, E I

    2001-04-01

    In the midbrain sound localization pathway of the barn owl, a map of auditory space is synthesized in the external nucleus of the inferior colliculus (ICX) and transmitted to the optic tectum. Early auditory experience shapes these maps of auditory space in part by modifying the tuning of the constituent neurons for interaural time difference (ITD), a primary cue for sound-source azimuth. Here we show that these adaptive modifications in ITD tuning correspond to changes in the pattern of connectivity within the inferior colliculus. We raised owls with an acoustic filtering device in one ear that caused frequency-dependent changes in sound timing and level. As reported previously, device rearing shifted the representation of ITD in the ICX and tectum but not in the primary source of input to the ICX, the central nucleus of the inferior colliculus (ICC). We applied the local anesthetic lidocaine (QX-314) iontophoretically in the ICC to inactivate small populations of neurons that represented particular values of frequency and ITD. We measured the effect of this inactivation in the optic tecta of a normal owl and owls raised with the device. In the normal owl, inactivation at a critical site in the ICC eliminated responses in the tectum to the frequency-specific ITD value represented at the site of inactivation in the ICC. The location of this site was consistent with the known pattern of ICC-ICX-tectum connectivity. In the device-reared owls, adaptive changes in the representation of ITD in the tectum corresponded to dramatic and predictable changes in the locations of the critical sites of inactivation in the ICC. Given that the abnormal representation of ITD in the tectum depended on frequency and was likely conveyed directly from the ICX, these results suggest that experience causes large-scale, frequency-specific adjustments in the pattern of connectivity between the ICC and the ICX.

  5. Intracellular responses to frequency modulated tones in the dorsal cortex of the mouse inferior colliculus

    Directory of Open Access Journals (Sweden)

    Ruediger eGeis

    2013-01-01

    Full Text Available Frequency modulations occur in many natural sounds, including vocalizations. The neuronal response to frequency modulated (FM stimuli has been studied extensively in different brain areas, with an emphasis on the auditory cortex and the central nucleus of the inferior colliculus. Here, we measured the responses to FM sweeps in whole-cell recordings from neurons in the dorsal cortex of the mouse inferior colliculus. Both up- and downward logarithmic FM sweeps were presented at two different speeds to both the ipsi- and the contralateral ear. Based on the number of action potentials that were fired, between 10-24% of cells were selective for rate or direction of the FM sweeps. A somewhat lower percentage of cells, 6-21%, showed selectivity based on EPSP size. To study the mechanisms underlying the generation of FM selectivity, we compared FM responses with responses to simple tones in the same cells. We found that if pairs of neurons responded in a similar way to simple tones, they generally also responded in a similar way to FM sweeps. Further evidence that FM selectivity can be generated within the dorsal cortex was obtained by reconstructing FM sweeps from the response to simple tones using three different models. In about half of the direction selective neurons the selectivity was generated by spectrally asymmetric synaptic inhibition. In addition, evidence for direction selectivity based on the timing of excitatory responses was also obtained in some cells. No clear evidence for the local generation of rate selectivity was obtained. We conclude that FM direction selectivity can be generated within the dorsal cortex of the mouse inferior colliculus by multiple mechanisms.

  6. Rotary condenser for SC2

    CERN Multimedia

    1975-01-01

    During 1975 the SC2 performance was improved among other things by redesigning some of the elements of the ROTCO (Annual Report 1975, p. 55). The photo shows an interior wiew of the housing of the rotary condenser and of the sixteen sets of shaped stator blades.

  7. Taurine acts as a glycine receptor agonist in slices of rat inferior colliculus.

    Science.gov (United States)

    Xu, Han; Wang, Wei; Tang, Zheng-Quan; Xu, Tian-Le; Chen, Lin

    2006-10-01

    Taurine is an important endogenous amino acid for neural development and for many physiological functions, but little is known about its functional role in the central auditory system. We investigated in young rats (P10-P14) the effects of taurine on the neuronal responses and synaptic transmissions in the central nucleus of the inferior colliculus (ICC) with a brain slice preparation and with whole-cell patch-clamp recordings. Perfusion of taurine at 1mM reliably evoked a current across the membrane and decreased the input resistance in neurons of the ICC. Taurine also depressed the spontaneous and current-evoked firing of ICC neurons. All these effects were reversible after washout and could be blocked by 3 microM strychnine, an antagonist of glycine receptors, but not by 10 microM bicuculline, an antagonist of GABA(A) receptors. When the inhibitory receptors were not pharmacologically blocked, taurine reversibly reduced the postsynaptic currents/potentials evoked by electrically stimulating the commissure of the inferior colliculus or the ipsilateral lateral lemniscus. The results demonstrate that taurine reduces the neuronal excitability and depresses the synaptic transmission in the ICC by activating glycine-gated chloride channels. Our findings suggest that taurine acts as a ligand of glycine receptors in the ICC and can be involved in the information processing of the central auditory system similarly like the neurotransmitter glycine.

  8. Dopamine D2-like receptors modulate unconditioned fear: role of the inferior colliculus.

    Directory of Open Access Journals (Sweden)

    Amanda Ribeiro de Oliveira

    Full Text Available BACKGROUND: A reduction of dopamine release or D2 receptor blockade in the terminal fields of the mesolimbic system clearly reduces conditioned fear. Injections of haloperidol, a preferential D2 receptor antagonist, into the inferior colliculus (IC enhance the processing of unconditioned aversive information. However, a clear characterization of the interplay of D2 receptors in the mediation of unconditioned and conditioned fear is still lacking. METHODS: The present study investigated the effects of intra-IC injections of the D2 receptor-selective antagonist sulpiride on behavior in the elevated plus maze (EPM, auditory-evoked potentials (AEPs to loud sounds recorded from the IC, fear-potentiated startle (FPS, and conditioned freezing. RESULTS: Intra-IC injections of sulpiride caused clear proaversive effects in the EPM and enhanced AEPs induced by loud auditory stimuli. Intra-IC sulpiride administration did not affect FPS or conditioned freezing. CONCLUSIONS: Dopamine D2-like receptors of the inferior colliculus play a role in the modulation of unconditioned aversive information but not in the fear-potentiated startle response.

  9. Regularly firing neurons in the inferior colliculus have a weak interaural intensity difference sensitivity.

    Science.gov (United States)

    Nasimi, Ali; Rees, Adrian

    2010-12-01

    The spike discharge regularity may be important in the processing of information in the auditory pathway. It has already been shown that many cells in the central nucleus of the inferior colliculus fire regularly in response to monaural stimulation by the best frequency tones. The aim of this study was to find how the regularity of units was affected by adding ipsilateral tone, and how interaural intensity difference sensitivity is related to regularity. Single unit recordings were performed from 66 units in the inferior colliculus of the anaesthetized guinea pig in response to the best frequency tone. Regularity of firing was measured by calculating the coefficient of variation as a function of time of a unit's response. There was a positive correlation between coefficient of variation and interaural intensity difference sensitivity, indicating that highly regular units had very weak and irregular units had strong interaural intensity difference sensitivity responses. Three effects of binaural interaction on the sustained regularity were observed: constant coefficient of variation despite change in rate (66% of the units), negative (20%) and positive (13%) rate-CV relationships. A negative rate-coefficient of variation relationship was the dominant pattern of binaural interaction on the onset regularity.

  10. Inhibition shapes selectivity to vocalizations in the inferior colliculus of awake mice

    Directory of Open Access Journals (Sweden)

    Zachary eMayko

    2012-10-01

    Full Text Available The inferior colliculus (IC is a major center for integration of auditory information as itreceives ascending projections from a variety of brainstem nuclei as well as descending projectionsfrom the thalamus and auditory cortex. The ascending projections are both excitatory andinhibitory and their convergence at the IC results in a microcircuitry that is important forshaping responses to simple, binaural, and modulated sounds in the IC. Here, we examined therole inhibition plays in shaping selectivity to vocalizations in the IC of awake, normal-hearingadult mice (CBA/CaJ strain. Neurons in the IC of mice show selectivity in their responses tovocalizations, and we hypothesized that this selectivity is created by inhibitory microcircuitryin the IC. We compared single unit responses in the IC to pure tones and a variety of ultrasonicmouse vocalizations before and after iontophoretic application of GABAA receptor (GABAARand glycine receptor (GlyR antagonists. The most pronounced effects of blocking GABAAR andGlyR on IC neurons were to increase spike rates and broaden excitatory frequency tuning curvesin response to pure tone stimuli, and to decrease selectivity to vocalizations. Thus, inhibitionplays an important role in creating selectivity to vocalizations in the inferior colliculus.

  11. 2010 ARRA Lidar: Hampton County (SC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Provide high density LiDAR elevation data map of Hampton County, SC. Provide Bare Earth DEM (vegetation removal) of Hampton County, SC.

  12. Magnetic moment of {sup 48}Sc

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsubo, T., E-mail: tohtsubo@np.gs.niigata-u.ac.jp; Kawamura, Y.; Ohya, S. [Niigata University, Department of Physics (Japan); Izumikawa, T. [Niigata University, Radioisotope Center (Japan); Nishimura, K. [Toyama University, Faculty of Engineering (Japan); Muto, S. [Neutron Science Laboratory, KEK (Japan); Shinozuka, T. [Tohoku University, Cyclotron and Radioisotope Center (Japan)

    2007-11-15

    Nuclear magnetic resonances were measured for {sup 48}Sc and {sup 44m}Sc oriented at 8 mK in an Fe host metal. The magnetic hyperfine splitting frequencies at an external magnetic field of 0.2 T were determined to be 63.22(11) MHz and 64.81(1) MHz for {sup 48}Sc and {sup 44m}Sc, respectively. With the known magnetic moment of {mu}({sup 44m}Sc)=+3.88 (1) {mu}{sub N}, the magnetic moment of {sup 48}Sc is deduced as {mu}({sup 44}Sc)=+3.785(12) {mu}{sub N}. The measured magnetic moment of {sup 48}Sc is discussed in terms of the shell model using the effective interactions.

  13. Xemilofiban: SC 54684A, xemlofiban.

    Science.gov (United States)

    2003-01-01

    Xemilofiban [SC 54684, SC 54684A (HCl), xemlofiban], a glycoprotein IIb/IIIa antagonist, is an orally available prodrug of a non-peptide mimetic of the tetrapeptide RGDF. It is converted to the active metabolite, SC 54701 (the free base form of SC 54701A). Development was initiated by Searle (Monsanto). Searle became part of Pharmacia Corporation, which was acquired by, and merged into, Pfizer in April 2003. Searle had co-development and co-marketing agreements with Sankyo in Japan; these have been discontinued. In January 2003, Pharmacia donated the intellectual property for xemilofiban to Western Michigan University. In February 2003, Western Michigan University granted an exclusive worldwide licence of xemilofiban to VDDI Pharmaceuticals (formerly Virtual Drug Development Inc.). Xemilofiban was in a phase III clinical trial, the Evaluation of Xemilofiban in Controlling Thrombotic Events (EXCITE) trial, with Searle (Monsanto) in the US and Europe for the treatment of thrombosis in patients with unstable angina pectoris and acute myocardial infarction undergoing angioplasty. However, as xemilofiban demonstrated no significant clinical benefit, Searle discontinued its development. In Japan, Sankyo discontinued the development of xemilofiban for thrombosis at phase II following Searle's decision to drop the project. VDDI Pharmaceuticals plans to develop xemilofiban in cardiovascular disorders following on from the phase III studies completed by Pharmacia; a restructured dosing schedule and narrowed patient selection will be used. VDDI has research facilities worldwide and will utilise facilities in Ireland for the European clinical development programme; research facilities in the Southwest Michigan Innovation Center are planned while the head office of VDDI is based in Tennessee. Xemilofiban is in phase III development for the treatment of cardiovascular disease in conjunction with percutaneous coronary intervention.

  14. Materials Characterization of High-Temperature Epoxy Resins: SC-79 and SC-15/SC-79 Blend

    Science.gov (United States)

    2011-03-01

    Army composite applications. SC-15 is a toughened commercial vacuum-assisted resin transfer molding ( VARTM ) resin produced by Applied Poleramic Inc...very well in VARTM processes and has good damage resistance in structural and ballistic applications. However, the relatively low glass transition...low-viscosity, two-phase toughened, cycloaliphatic amine–cured commercial VARTM resin system designed to be easy to handle and have a long processing

  15. Connections of the superior paraolivary nucleus of the rat: II. Reciprocal connections with the tectal longitudinal column

    Directory of Open Access Journals (Sweden)

    Antonio eViñuela

    2011-02-01

    Full Text Available The superior paraolivary nucleus (SPON, a prominent GABAergic center of the mammalian auditory brainstem, projects to the ipsilateral inferior colliculus (IC and sends axons through the commissure of the IC (CoIC. Herein we demonstrate that the SPON is reciprocally connected with the recently discovered tectal longitudinal column (TLC. The TLC is a long and narrow structure that spans nearly the entire midbrain tectum longitudinally, immediately above the periaqueductal gray matter (PAG and very close to the midline.Unilateral injections of biotinylated dextran into the SPON of the rat label abundant terminal fibers in the TLC of both sides, with an ipsilateral predominance. The SPON provides a dense innervation of the entire rostrocaudal extent of the ipsilateral TLC, and a relatively sparser innervation of the caudal and rostral portions of the contralateral TLC. SPON fibers reach the TLC by two routes: as collaterals of axons of the CoIC, and as axons that circumvent the ipsilateral IC before traveling in the deep layers of the superior colliculus.The density of these projections identifies SPON as a significant source of input to the TLC. Other targets of the SPON discovered in this study include the deep layers of the superior colliculus and the PAG. The same experiments reveal numerous labeled cell bodies in the TLC, interspersed among the labeled SPON fibers. This observation suggests that the SPON is a significant target of TLC projections.The discovery of novel reciprocal connections between the SPON and the TLC opens unexpected avenues for investigation of sound processing in mammalian brainstem circuits.

  16. Topography of acoustic response characteristics in the midbrain inferior colliculus of Kunming mouse

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Topography of acoustic response characteristics of the midbrain inferior colliculus (IC) of the Kunming mouse was studied by using extracellular recording techniques. The characteristic frequency (CF) range represented in the different divisions of the IC differed markedly: 4-15 kHz in the dorsal cortex (DC), 10-70 kHz in the central nucleus (CN), and 4-35 kHz in the external cortex (EC). The CF in the CN increased from dorsal and lateral to ventral and medial, higher CFs represented at its ventromedial part and lower CFs at its dorsal part. The isofrequency contours of CFs were incurvate. Minimum thresholds (MT) of the auditory neurons in DC and the central part of CN were lower (about 10 dB SPL), but considerably higher in the dorsal and ventral region of EC. Results suggest that each of the divisions in the mouse IC may have different auditory functions.

  17. Neural interactions in unilateral colliculus and between bilateral colliculi modulate auditory signal processing

    Science.gov (United States)

    Mei, Hui-Xian; Cheng, Liang; Chen, Qi-Cai

    2013-01-01

    In the auditory pathway, the inferior colliculus (IC) is a major center for temporal and spectral integration of auditory information. There are widespread neural interactions in unilateral (one) IC and between bilateral (two) ICs that could modulate auditory signal processing such as the amplitude and frequency selectivity of IC neurons. These neural interactions are either inhibitory or excitatory, and are mostly mediated by γ-aminobutyric acid (GABA) and glutamate, respectively. However, the majority of interactions are inhibitory while excitatory interactions are in the minority. Such unbalanced properties between excitatory and inhibitory projections have an important role in the formation of unilateral auditory dominance and sound location, and the neural interaction in one IC and between two ICs provide an adjustable and plastic modulation pattern for auditory signal processing. PMID:23626523

  18. Neural interactions in unilateral colliculus and between bilateral colliculi modulate auditory signal processing.

    Science.gov (United States)

    Mei, Hui-Xian; Cheng, Liang; Chen, Qi-Cai

    2013-01-01

    In the auditory pathway, the inferior colliculus (IC) is a major center for temporal and spectral integration of auditory information. There are widespread neural interactions in unilateral (one) IC and between bilateral (two) ICs that could modulate auditory signal processing such as the amplitude and frequency selectivity of IC neurons. These neural interactions are either inhibitory or excitatory, and are mostly mediated by γ-aminobutyric acid (GABA) and glutamate, respectively. However, the majority of interactions are inhibitory while excitatory interactions are in the minority. Such unbalanced properties between excitatory and inhibitory projections have an important role in the formation of unilateral auditory dominance and sound location, and the neural interaction in one IC and between two ICs provide an adjustable and plastic modulation pattern for auditory signal processing.

  19. Interaural time sensitivity of high-frequency neurons in the inferior colliculus.

    Science.gov (United States)

    Yin, T C; Kuwada, S; Sujaku, Y

    1984-11-01

    Recent psychoacoustic experiments have shown that interaural time differences provide adequate cues for lateralizing high-frequency sounds, provided the stimuli are complex and not pure tones. We present here physiological evidence in support of these findings. Neurons of high best frequency in the cat inferior colliculus respond to interaural phase differences of amplitude modulated waveforms, and this response depends upon preservation of phase information of the modulating signal. Interaural phase differences were introduced in two ways: by interaural delays of the entire waveform and by binaural beats in which there was an interaural frequency difference in the modulating waveform. Results obtained with these two methods are similar. Our results show that high-frequency cells can respond to interaural time differences of amplitude modulated signals and that they do so by a sensitivity to interaural phase differences of the modulating waveform.

  20. Dissonance encoding in human inferior colliculus covaries with individual differences in dislike of dissonant music.

    Science.gov (United States)

    Kim, Seung-Goo; Lepsien, Jöran; Fritz, Thomas Hans; Mildner, Toralf; Mueller, Karsten

    2017-07-18

    Harmony is one of the most fundamental elements of music that evokes emotional response. The inferior colliculus (IC) has been known to detect poor agreement of harmonics of sound, that is, dissonance. Electrophysiological evidence has implicated a relationship between a sustained auditory response mainly from the brainstem and unpleasant emotion induced by dissonant harmony. Interestingly, an individual's dislike of dissonant harmony of an individual correlated with a reduced sustained auditory response. In the current paper, we report novel evidence based on functional magnetic resonance imaging (fMRI) for such a relationship between individual variability in dislike of dissonance and the IC activation. Furthermore, for the first time, we show how dissonant harmony modulates functional connectivity of the IC and its association with behaviourally reported unpleasantness. The current findings support important contributions of low level auditory processing and corticofugal interaction in musical harmony preference.

  1. Deactivation of the inferior colliculus by cooling demonstrates intercollicular modulation of neuronal activity

    Directory of Open Access Journals (Sweden)

    Llwyd David Orton

    2012-12-01

    Full Text Available The auditory pathways coursing through the brainstem are organised bilaterally in mirror image about the midline and at several levels the two sides are interconnected. One of the most prominent points of interconnection is the commissure of the inferior colliculus (CoIC. Anatomical studies have revealed that these fibres make reciprocal connections which follow the tonotopic organisation of the inferior colliculus (IC, and that the commissure contains both excitatory and, albeit fewer, inhibitory fibres. The role of these connections in sound processing is largely unknown. Here we describe a method to address this question in the anaesthetised guinea pig. We used a cryoloop placed on one IC to produce reversible deactivation while recording electrophysiological responses to sounds in both ICs. We recorded single units, multi-unit clusters and local field potentials (LFPs before, during and after cooling. The degree and spread of cooling was measured with a thermocouple placed in the IC and other auditory structures. Cooling sufficient to eliminate firing was restricted to the IC contacted by the cryoloop. The temperature of other auditory brainstem structures, including the contralateral IC and the cochlea were minimally affected. Cooling below 20 °C reduced or eliminated the firing of action potentials in frequency laminae at depths corresponding to characteristic frequencies up to ~8 kHz. Modulation of neural activity also occurred in the un-cooled IC with changes in single unit firing and LFPs. Components of LFPs signalling lemniscal afferent input to the IC showed little change in amplitude or latency with cooling, whereas the later components, which likely reflect inter- and intra-collicular processing, showed marked changes in form and amplitude. We conclude that the cryoloop is an effective method of selectively deactivating one IC in guinea pig, and demonstrate that auditory processing in the IC is strongly influenced by the other.

  2. Response of auditory units in the barn owl's inferior colliculus to continuously varying interaural phase differences.

    Science.gov (United States)

    Moiseff, A; Haresign, T

    1992-06-01

    1. We studied the response of single units in the central nucleus of the inferior colliculus (ICc) of the barn owl (Tyto alba) to continuously varying interaural phase differences (IPDs) and static IPDs. Interaural phase was varied in two ways: continuously, by delivering tones to each ear that varied by a few hertz (binaural beat, Fig. 1), and discretely, by delaying in fixed steps the phase of sound delivered to one ear relative to the other (static phase). Static presentations were repeated at several IPDs to characterize interaural phase sensitivity. 2. Units sensitive to IPDs responded to the binaural beat stimulus over a broad range of delta f(Fig. 4). We selected a 3-Hz delta f for most of our comparative measurements on the basis of constraints imposed by our stimulus generation system and because it allowed us to reduce the influence of responses to stimulus onset and offset (Fig. 3A). 3. Characteristic interaural time or phase sensitivity obtained by the use of the binaural beat stimulus were comparable with those obtained by the use of the static technique (Fig. 5; r2 = 0.93, Fig. 6). 4. The binaural beat stimulus facilitated the measurement of characteristic delay (CD) and characteristic phase (CP) of auditory units. We demonstrated that units in the owl's inferior colliculus (IC) include those that are maximally excited by specific IPDs (CP = 0 or 1.0) as well as those that are maximally suppressed by specific IPDs (CP = 0.5; Figs. 7 and 8). 5. The selectivity of units sensitive to IPD or interaural time difference (ITD) were weakly influenced by interaural intensity difference (IID).(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Main: 3SC2 [RPSD[Archive

    Lifescience Database Archive (English)

    Full Text Available 3SC2 小麦 Bread Wheat Triticum aestivum Serine Carboxypeptidase Ii Chains A And B Nam... 1WHS; X-ray; A=6-260, B=266-418.|PDB; 1WHT; X-ray; A=5-260, B=266-418.|PDB; 3SC2; X-ray; A=1-259, B=266-417...WHDAPRSMLPIYRELIAAGLRIWVFSGDTDAVVPLTATRYSIGALGLPTTTSWYPWYDDQEVGGWSQVYKGLTLVSVRGAGHEVPLHRPRQALVLFQYFLQGKPMPGQTKNAT wheat_3SC2.jpg ...

  4. Academic Training - Pulsed SC Magnets

    CERN Multimedia

    Françoise Benz

    2006-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 2, 3, June 29, 30, 31 May, 1, 2 June 11:00-12:00 - Auditorium, bldg 500 Pulsed SC Magnets by M. Wilson Lecture 1. Introduction to Superconducting Materials Type 1,2 and high temperature superconductors; their critical temperature, field & current density. Persistent screening currents and the critical state model. Lecture 2. Magnetization and AC Loss How screening currents cause irreversible magnetization and hysteresis loops. Field errors caused by screening currents. Flux jumping. The general formulation of ac loss in terms of magnetization. AC losses caused by screening currents. Lecture 3. Twisted Wires and Cables Filamentary composite wires and the losses caused by coupling currents between filaments, the need for twisting. Why we need cables and how the coupling currents in cables contribute more ac loss. Field errors caused by coupling currents. Lecture 4. AC Losses in Magnets, Cooling and Measurement Summary of all loss mech...

  5. Superior Hiking Trail

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  6. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  7. Superior Hiking Trail Facilities

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  8. The selective neurotoxin DSP-4 impairs the noradrenergic projections from the locus coeruleus to the inferior colliculus in rats.

    OpenAIRE

    Sebastián eHormigo; José de Anchieta de Castro e Horta Junior; Ricardo eGómez-Nieto; López García, Dolores E.

    2012-01-01

    The inferior colliculus (IC) and the locus coeruleus (LC) are two midbrain nuclei that integrate multimodal information and play a major role in novelty detection to elicit an orienting response. Despite the reciprocal connections between these two structures, the projection pattern and target areas of the LC within the subdivisions of the rat IC are still unknown. Here, we used tract-tracing approaches combined with immunohistochemistry, densitometry and confocal microscopy analysis to descr...

  9. The selective neurotoxin DSP-4 impairs the noradrenergic projections from the locus coeruleus to the inferior colliculus in rats

    OpenAIRE

    Hormigo, Sebastián; Horta Júnior, José de Anchieta de Castro e; Gómez-Nieto, Ricardo; López, Dolores E.

    2012-01-01

    The inferior colliculus (IC) and the locus coeruleus (LC) are two midbrain nuclei that integrate multimodal information and play a major role in novelty detection to elicit an orienting response. Despite the reciprocal connections between these two structures, the projection pattern and target areas of the LC within the subdivisions of the rat IC are still unknown. Here, we used tract-tracing approaches combined with immunohistochemistry, densitometry, and confocal microscopy (CM) analysis to...

  10. 46 CFR 7.70 - Folly Island, SC to Hilton Head Island, SC.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Folly Island, SC to Hilton Head Island, SC. 7.70 Section... BOUNDARY LINES Atlantic Coast § 7.70 Folly Island, SC to Hilton Head Island, SC. (a) A line drawn from the southernmost extremity of Folly Island to latitude 32°35′ N. longitude 79°58.2′ W. (Stono Inlet Lighted...

  11. rotor of the SC rotating condenser

    CERN Multimedia

    1974-01-01

    The rotor of the rotating condenser was installed instead of the tuning fork as the modulating element of the radiofrequency system, when the SC accelerator underwent extensive improvements between 1973 to 1975 (see object AC-025). The SC was the first accelerator built at CERN. It operated from August 1957 until it was closed down at the end of 1990.

  12. Radiation Protection Section (SC/SL/RP)

    CERN Multimedia

    2006-01-01

    We should like to inform you that the Radiation Protection Section (SC/SL/RP) located on the Prévessin site has moved from Building 865 (ground floor) to new premises in Wing A of Building 892 (second floor). Telephone numbers remain the same. SC/SL/RP section

  13. Cs3ScCl6

    Directory of Open Access Journals (Sweden)

    Matthew D. Ward

    2014-06-01

    Full Text Available Crystals of tricaesium scandium(III hexachloride were obtained as a side product from the reaction of U, SnCl2, Sc, and S in a CsCl flux at 1073 K. Cs3ScCl6 crystallizes in the Rb3YCl6 structure type. The asymmetric unit comprises three Cs sites, two Sc sites, and six Cl sites, all of which have site symmetry 1, except for the two Sc sites that have site symmetries of 2 and -1, respectively. The structure is composed of isolated [ScCl6]3− octahedra that are surrounded by Cs+ cations. Two Cs+ cations have interactions with eight Cl− anions, while the third has interactions with ten Cl− anions.

  14. PERSISTENT LEFT SUPERIOR VENACAVA

    Directory of Open Access Journals (Sweden)

    Devinder Singh

    2014-05-01

    Full Text Available A Persistent Left Superior Venacava (PLSVC is the most common variation of the thoracic venous system and rare congenital vascular anomaly and is prevalent in 0.3% of the population. It may be associated with other cardiovascular abnormalities including atrial septal defect, bicuspid aortic valve, coarctation of aorta, coronary sinus ostial atresia, and cor triatriatum. Incidental rotation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. The diagnosis should be confirmed by saline contrast echocardiography. Condition is usually asymptomatic. Here we present a rare case of persistent left superior vena cava presented in OPD with dyspnoea & palpitations.

  15. Changes in the response properties of inferior colliculus neurons relating to tinnitus

    Directory of Open Access Journals (Sweden)

    Joel I Berger

    2014-10-01

    Full Text Available Tinnitus is often identified in animal models by using the gap prepulse inhibition of acoustic startle (GPIAS. Impaired gap detection following acoustic over-exposure (AOE is thought to be caused by tinnitus ‘filling in’ the gap, thus reducing its salience. This presumably involves altered perception, and could conceivably be caused by changes at the level of the neocortex, i.e. cortical reorganization. Alternatively, reduced gap detection ability might reflect poorer temporal processing in the brainstem, caused by AOE; in which case, impaired gap detection would not be a reliable indicator of tinnitus. We tested the latter hypothesis by examining gap detection in inferior colliculus (IC neurons following AOE. Seven of nine unilaterally noise-exposed guinea pigs exhibited behavioural evidence of tinnitus. In these tinnitus animals, neural gap detection thresholds in the IC significantly increased in response to broadband noise stimuli, but not to pure tones or narrowband noise. In addition, when IC neurons were sub-divided according to temporal response profile (onset vs. sustained firing patterns, we found a significant increase in the proportion of onset-type responses after AOE. Importantly, however, gap detection thresholds were still considerably shorter than gap durations commonly used in objective behavioural tests for tinnitus. These data indicate that the neural changes observed in the IC are insufficient to explain deficits in behavioural gap detection that are commonly attributed to tinnitus. The subtle changes in IC neuron response profiles following AOE warrant further investigation.

  16. Stimulus-specific adaptation and deviance detection in the inferior colliculus

    Directory of Open Access Journals (Sweden)

    Yaneri eAguilar Ayala

    2013-01-01

    Full Text Available Deviancy detection in the continuous flow of sensory information into the central nervous system is of vital importance for animals. The task requires neuronal mechanisms that allow for an efficient representation of the environment by removing statistically redundant signals. Recently, the neuronal principles of auditory deviance detection have been approached by studying the phenomenon of stimulus-specific adaptation (SSA. SSA is a reduction in the responsiveness of a neuron to a common or repetitive sound while the neuron remains highly sensitive to rare sounds (Ulanovsky et al., 2003. This phenomenon could enhance the saliency of unexpected, deviant stimuli against a background of repetitive signals. SSA shares many similarities with the evoked potential known as the ‘mismatch negativity,’ and it has been linked to cognitive process such as auditory memory and scene analysis (Winkler et al., 2009 as well as to behavioral habituation (Netser et al., 2011. Neurons exhibiting SSA can be found at several levels of the auditory pathway, from the inferior colliculus (IC up to the auditory cortex (AC. In this review, we offer an account of the state-of-the art of SSA studies in the IC with the aim of contributing to the growing interest in the single-neuron electrophysiology of auditory deviance detection. The dependence of neuronal SSA on various stimulus features, e.g., probability of the deviant stimulus and repetition rate, and the roles of the AC and inhibition in shaping SSA at the level of the IC are addressed.

  17. Serotonin in the inferior colliculus fluctuates with behavioral state and environmental stimuli.

    Science.gov (United States)

    Hall, Ian C; Rebec, George V; Hurley, Laura M

    2010-04-01

    Neuromodulation by serotonin (5-HT) could link behavioral state and environmental events with sensory processing. Within the auditory system, the presence of 5-HT alters the activity of neurons in the inferior colliculus (IC), but the conditions that influence 5-HT neurotransmission in this region of the brain are unknown. We used in vivo voltammetry to measure extracellular 5-HT in the IC of behaving mice to address this issue. Extracellular 5-HT increased with the recovery from anesthesia, suggesting that the neuromodulation of auditory processing is correlated with the level of behavioral arousal. Awake mice were further exposed to auditory (broadband noise), visual (light) or olfactory (2,5-dihydro-2,4,5-trimethylthiazoline, TMT) stimuli, presented with food or confined in a small arena. Only the auditory stimulus or restricted movement increased the concentration of extracellular 5-HT in the IC. Changes occurred within minutes of stimulus onset, with the auditory stimulus increasing extracellular 5-HT by an average of 5% and restricted movement increasing it by an average of 14%. These findings suggest that the neuromodulation of auditory processing by 5-HT is a dynamic process that is dependent on internal state and behavioral conditions.

  18. Anatomical characterization of subcortical descending projections to the inferior colliculus in mouse.

    Science.gov (United States)

    Patel, Mili B; Sons, Stacy; Yudintsev, Georgiy; Lesicko, Alexandria M H; Yang, Luye; Taha, Gehad A; Pierce, Scott M; Llano, Daniel A

    2017-03-01

    Descending projections from the thalamus and related structures to the midbrain are evolutionarily highly conserved. However, the basic organization of this auditory thalamotectal pathway has not yet been characterized. The purpose of this study was to obtain a better understanding of the anatomical and neurochemical features of this pathway. Analysis of the distributions of retrogradely labeled cells after focal injections of retrograde tracer into the inferior colliculus (IC) of the mouse revealed that most of the subcortical descending projections originated in the brachium of the IC and the paralaminar portions of the auditory thalamus. In addition, the vast majority of thalamotectal cells were found to be negative for the calcium-binding proteins calbindin, parvalbumin, or calretinin. Using two different strains of GAD-GFP mice, as well as immunostaining for GABA, we found that a subset of neurons in the brachium of the IC is GABAergic, suggesting that part of this descending pathway is inhibitory. Finally, dual retrograde injections into the IC and amygdala plus corpus striatum as well into the IC and auditory cortex did not reveal any double labeling. These data suggest that the thalamocollicular pathway comprises a unique population of thalamic neurons that do not contain typical calcium-binding proteins and do not project to other paralaminar thalamic forebrain targets, and that a previously undescribed descending GABAergic pathway emanates from the brachium of the IC. J. Comp. Neurol. 525:885-900, 2017. © 2016 Wiley Periodicals, Inc.

  19. Distribution of GABAergic cells in the inferior colliculus that project to the thalamus

    Directory of Open Access Journals (Sweden)

    Jeffrey G Mellott

    2014-03-01

    Full Text Available A GABAergic component has been identified in the projection from the inferior colliculus (IC to the medial geniculate body (MG in cats and rats. We sought to determine if this GABAergic pathway exists in guinea pig, a species widely used in auditory research. The guinea pig IC contains GABAergic cells, but their relative abundance in the IC and their relative contributions to tectothalamic projections are unknown. We identified GABAergic cells with immunochemistry for glutamic acid decarboxylase (GAD and determined that ~21% of IC neurons are GABAergic. We then combined retrograde tracing with GAD immunohistochemistry to identify the GABAergic tectothalamic projection. Large injections of Fast Blue, red fluorescent beads or FluoroGold were deposited to include all subdivisions of the MG. The results demonstrate a GABAergic pathway from each IC subdivision to the ipsilateral MG. GABAergic cells constitute ~22% of this ipsilateral pathway. In addition, each subdivision of the IC had a GABAergic projection to the contralateral MG. Measured by number of tectothalamic cells, the contralateral projection is about 10% of the size of the ipsilateral projection. GABAergic cells constitute about 20% of the contralateral projection. In summary, the results demonstrate a tectothalamic projection in guinea pigs that originates in part from GABAergic cells that project ipsilaterally or contralaterally to the MG. The results show similarities to both rats and cats, and carry implications for the role of GABAergic tectothalamic projections vis-à-vis the presence (in cats or near absence (in rats and guinea pigs of GABAergic interneurons in the MG.

  20. Age-related neurochemical changes in the rhesus macaque inferior colliculus.

    Directory of Open Access Journals (Sweden)

    James eEngle

    2014-04-01

    Full Text Available Age-related hearing loss (ARHL is marked by audiometric hearing deficits that propagate along the auditory pathway. Neurochemical changes as a function of aging have also been identified in neurons along the auditory pathway in both rodents and carnivores, however, very little is known about how these neurochemicals change in the non-human primate. To examine how these compensatory neurochemical changes relate to normal aging and audiometric sensitivity along the auditory pathway, we collected auditory brainstem responses (ABRs and brain specimens from seven rhesus monkeys spanning in age from 15 to 35 years old, and examined the relationship between click evoked ABR thresholds and the ABR evoked pure tone average and changes in the number of parvalbumin and NADPH-diaphorase positive cells in the auditory midbrain. We found that the number of parvalbumin positive cells in the central nucleus and the surrounding cortex regions of the inferior colliculus were strongly correlated with advancing age and ABR pure tone average. We also found that the numbers of NADPHd positive cells in these same regions were not associated with normal aging or changes in the ABR thresholds. These findings suggest that the auditory midbrain undergoes an up-regulation of parvalbumin expressing neurons with aging that is related to changes in the processing of frequencies across the audiometric range.

  1. An in vivo investigation of inferior colliculus single neuron responses to cochlear nucleus pulse train stimulation.

    Science.gov (United States)

    Mauger, Stefan J; Shivdasani, Mohit N; Rathbone, Graeme D; Paolini, Antonio G

    2012-12-01

    The auditory brain stem implant (ABI) is being used clinically to restore hearing to patients unable to benefit from a cochlear implant (CI). Speech perception outcomes for ABI users are typically poor compared with most CI users. The ABI is implanted either on the surface of or penetrating through the cochlear nucleus in the auditory brain stem and uses stimulation strategies developed for auditory nerve stimulation with a CI. Although the stimulus rate may affect speech perception outcomes with current stimulation strategies, no studies have systematically investigated the effect of stimulus rate electrophysiologically or clinically. We therefore investigated rate response properties and temporal response properties of single inferior colliculus (IC) neurons from penetrating ABI stimulation using stimulus rates ranging from 100 to 1,600 pulses/s in the rat. We found that the stimulus rate affected the proportion of response types, thresholds, and dynamic ranges of IC activation. The stimulus rate was also found to affect the temporal properties of IC responses, with higher rates providing more temporally similar responses to acoustic stimulation. Suppression of neural firing and inhibition in IC neurons was also found, with response properties varying with the stimulus rate. This study demonstrated that changes in the ABI stimulus rate results in significant differences in IC neuron response properties. Due to electrophysiological differences, the stimulus rate may also change perceptual properties. We suggest that clinical evaluation of the ABI stimulus rate should be performed.

  2. Transient down-regulation of sound-induced c-Fos protein expression in the inferior colliculus after ablation of the auditory cortex

    Directory of Open Access Journals (Sweden)

    Cheryl Clarkson

    2010-10-01

    Full Text Available We tested whether lesions of the excitatory glutamatergic projection from the auditory cortex to the inferior colliculus induce plastic changes in neurons of this nucleus. Changes in neuronal activation in the inferior colliculus deprived unilaterally of the cortico-collicular projection were assessed by quantitative c-Fos immunocytochemistry. Densitometry and stereology measures of sound-induced c-Fos immunoreactivity in the inferior colliculus showed diminished labeling at 1, 15, 90 and 180 days after lesions to the auditory cortex suggesting protein down-regulation, at least up to 15 days post-lesion. Between 15 and 90 days after the lesion, c-Fos labeling recovers, approaching control values at 180 days. Thus, glutamatergic excitation from the cortex maintains sound-induced activity in neurons of the inferior colliculus. Subdivisions of this nucleus receiving a higher density of cortical innervation such as the dorsal cortex showed greater changes in c-Fos immunoreactivity, suggesting that the anatomical strength of the projection correlates with effect strength. Therefore, after damage of the corticofugal projection, neurons of the inferior colliculus down-regulate and further recover sound-induced c-Fos protein expression. This may be part of cellular mechanisms aimed at balancing or adapting neuronal responses to altered synaptic inputs.

  3. SC-FDMA for mobile communications

    CERN Document Server

    Abd El-Samie, Fathi E

    2013-01-01

    SC-FDMA for Mobile Communications examines Single-Carrier Frequency Division Multiple Access (SC-FDMA). Explaining this rapidly evolving system for mobile communications, it describes its advantages and limitations and outlines possible solutions for addressing its current limitations. The book explores the emerging trend of cooperative communication with SC-FDMA and how it can improve the physical layer security. It considers the design of distributed coding schemes and protocols for wireless relay networks where users cooperate to send their data to the destination. Supplying you with the re

  4. z206sc_video_observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents video observations from cruise Z206SC for the Santa Barbara Channel region and beyond in southern California. The vector data file is...

  5. z107sc_video_observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents video observations from cruise Z107SC for the Santa Barbara Channel region and beyond in southern California. The vector data file is...

  6. z206sc_video_observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents video observations from cruise Z206SC for the Santa Barbara Channel region and beyond in southern California. The vector data file is...

  7. z107sc_video_observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents video observations from cruise Z107SC for the Santa Barbara Channel region and beyond in southern California. The vector data file is...

  8. Bandwidth challenge teams at SC2003 conference

    CERN Multimedia

    2003-01-01

    Results from the fourth annual High-Performance Bandwidth Challenge, held in conjunction with SC2003, the international conference on high-performance computing and networking which occurred last week in Phoenix, AZ (1 page).

  9. Recrystallization of Al-Sc alloys

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Toropova, L.S.; Bykov, Yu.G.; Ber, L.B.

    Scandium effect on the temperature range of aluminium recrystallization was investigated. Al-Sc alloys were studied under cold rolled and hot pressed conditions. It is found that the temperature range of Al-Sc alloy recrystallization depends on ScAl/sub 3/ particle dispersion during recrystallization heats. During heating in quenched alloys at 200-300 deg C decomposition occurs which prevents recrystallization, In the alloys with scandium contents less 0.2% decomposition and recrystallization processes pass simultaneously. In quenched alloys with scandium contents over 0.2% and in aged alloys the initiation and subsequent development of recrystallization are determined by the processes of coalescence and solution of ScAl/sub 3/ phase particles.

  10. Air Superiority Fighter Characteristics.

    Science.gov (United States)

    1998-06-05

    many a dispute could have been deflated into a single paragraph if the disputants had just dared to define their terms.7 Aristotle ...meaningful. This section will expand on some key ideology concepts. The phrase "air superiority fighter" may bring to mind visions of fighter... biographies are useful in garnering airpower advocate theories as well as identifying key characteristics. Air campaign results, starting with World

  11. Natural vocalizations in the mammalian inferior colliculus are broadly encoded by a small number of independent multi-unit clusters

    Directory of Open Access Journals (Sweden)

    Dominika eLyzwa

    2016-02-01

    Full Text Available How complex natural sounds are represented by the main converging center of the auditory midbrain, the central inferior colliculus, is an open question. We applied neural discrimination to determine the variation of detailed encoding of individual vocalizations across the best frequency gradient of the central inferior colliculus. The analysis was based on collective responses from several neurons. These multi-unit spike trains were recorded from guinea pigs exposed to a spectrotemporally rich set of eleven species-specific vocalizations. Spike trains of disparate units from the same recording were combined in order to investigate whether groups of multi-unit clusters represent the whole set of vocalizations more reliably than only one unit, and whether temporal response correlations between them facilitate an unambiguous neural representation of the vocalizations. We found a spatial distribution of the capability to accurately encode groups of vocalizations across the best frequency gradient. Different vocalizations are optimally discriminated at different locations of the best frequency gradient. Furthermore, groups of a few multi-unit clusters yield improved discrimination over only one multi-unit cluster betweenall tested vocalizations. However, temporal response correlations between units do not yield better discrimination. Our study is based on a large set of units of simultaneously recorded responses from several guinea pigs and electrode insertion positions. Our findings suggest abroadly distributed code for behaviorally relevant vocalizations in the mammalian inferior colliculus.Responses from a few non-interacting units are sufficient to faithfully represent the whole set of studied vocalizations with diverse spectrotemporal properties.

  12. EFFECTS OF CHRONIC ADMINISTRATION OF EFAVIRENZ ON THE BRAIN AND INFERIOR COLLICULUS WEIGHTS OF ADULT WISTAR RATS

    Directory of Open Access Journals (Sweden)

    J. O. Adjene

    2009-01-01

    Full Text Available The effects of chronic administration of Efavirenz commonly used as part of highly active antiretroviral therapy (HAART for the treatment of Human Immunodeficiency Virus (HIV type-1 on the weight of the brain and inferior colliculus of adult wistar rats was carefully studied. The rats of both sexes (n=16, with an average weight of 200g were randomly assigned into treatment (n=8 and control (n=8 groups. The rats in the treatment group received 600 mg/70 kg body weight of Efavirenz dissolved in distilled water daily for 30 days (thirty days through the orogastric tube. The control group received equal volume of distilled water daily for 30 days through the same route. The rats were fed with grower's mash obtained from Edo Feeds and Flour Mill Limited, Ewu, Edo state, Nigeria and given water liberally. The rats were sacrificed by cervical dislocation method on the thirty-first day of the experiment and the brains were carefully dissected out, dried, weighed and recorded using the Mettler Toledo weighing balance. The findings indicate that there was a significant decrease (P < 0.05 in the dry brain weight and an increase in the relative dry brain weight of the treatment group as compared with the control group in this experiment. There was also a significant increase (P < 0.05 in the weight of the dry inferior colliculus per total dry brain weight in the treatment group when compared with the control group. However, the relative dry inferior colliculus weight was significantly higher (P < 0.05 in the treatment group also than that of the control group in this experiment

  13. Dynamic temporal signal processing in the inferior colliculus of echolocating bats

    Science.gov (United States)

    Jen, Philip H.-S.; Wu, Chung Hsin; Wang, Xin

    2012-01-01

    In nature, communication sounds among animal species including humans are typical complex sounds that occur in sequence and vary with time in several parameters including amplitude, frequency, duration as well as separation, and order of individual sounds. Among these multiple parameters, sound duration is a simple but important one that contributes to the distinct spectral and temporal attributes of individual biological sounds. Likewise, the separation of individual sounds is an important temporal attribute that determines an animal's ability in distinguishing individual sounds. Whereas duration selectivity of auditory neurons underlies an animal's ability in recognition of sound duration, the recovery cycle of auditory neurons determines a neuron's ability in responding to closely spaced sound pulses and therefore, it underlies the animal's ability in analyzing the order of individual sounds. Since the multiple parameters of naturally occurring communication sounds vary with time, the analysis of a specific sound parameter by an animal would be inevitably affected by other co-varying sound parameters. This is particularly obvious in insectivorous bats, which rely on analysis of returning echoes for prey capture when they systematically vary the multiple pulse parameters throughout a target approach sequence. In this review article, we present our studies of dynamic variation of duration selectivity and recovery cycle of neurons in the central nucleus of the inferior colliculus of the frequency-modulated bats to highlight the dynamic temporal signal processing of central auditory neurons. These studies use single pulses and three biologically relevant pulse-echo (P-E) pairs with varied duration, gap, and amplitude difference similar to that occurring during search, approach, and terminal phases of hunting by bats. These studies show that most collicular neurons respond maximally to a best tuned sound duration (BD). The sound duration to which these neurons are

  14. Sc3N and Sc2C2 encapsulated B40: Smarter than its carbon analogue

    Science.gov (United States)

    Shah, Esha V.; Roy, Debesh R.

    2016-10-01

    A detailed comparative investigation on the recently synthesised B40 and C40 along with their metal nitride (Sc3N)and carbide (Sc2C2) encapsulated endohedral fullerenes, is performed under density functional theory for the first time. The structures, electronic, thermodynamic and magnetic properties of all the considered compounds are explored in detail. The present study identifies borospherene (B40) and its encapsulated nitride (Sc3N@B40) and carbide (Sc2C2@B40) endohedral borofullerenes as the better candidates for future novel nano-applications compared to their carbon bucky ball analogues.

  15. Fatigue Performance of Friction-Stir-Welded Al-Mg-Sc Alloy

    Science.gov (United States)

    Zhemchuzhnikova, Daria; Mironov, Sergey; Kaibyshev, Rustam

    2017-01-01

    Fatigue behavior of a friction-stir-welded Al-Mg-Sc alloy was examined in cast and hot-rolled conditions. In both cases, the joints failed in the base material region and therefore the joint efficiency was 100 pct. The specimens machined entirely from the stir zone demonstrated fatigue strength superior to that of the base material in both preprocessed tempers. It was shown that the excellent fatigue performance of friction-stir joints was attributable to the ultra-fine-grained microstructure, the low dislocation density evolved in the stir zone, and the preservation of Al3Sc coherent dispersoids during welding. The formation of such structure hinders the initiation and growth of fatigue microcracks that provides superior fatigue performance of friction-stir welds.

  16. Mechanical Properties and Microstructure of TIG and FSW Joints of a New Al-Mg-Mn-Sc-Zr Alloy

    Science.gov (United States)

    Xu, Guofu; Qian, Jian; Xiao, Dan; Deng, Ying; Lu, Liying; Yin, Zhimin

    2016-04-01

    A new Al-5.8%Mg-0.4%Mn-0.25%Sc-0.10%Zr (wt.%) alloy was successfully welded by tungsten inert gas (TIG) and friction stir welding (FSW) techniques, respectively. The mechanical properties and microstructure of the welded joints were investigated by microhardness measurements, tensile tests, and microscopy methods. The results show that the ultimate tensile strength, yield strength, and elongation to failure are 358, 234 MPa, and 27.6% for TIG welded joint, and 376, 245 MPa and 31.9% for FSW joint, respectively, showing high strength and superior ductility. The TIG welded joint fails in the heat-affected zone and the fracture of FSW joint is located in stirred zone. Al-Mg-Mn-Sc-Zr alloy is characterized by lots of dislocation tangles and secondary coherent Al3(Sc,Zr) particles. The superior mechanical properties of the TIG and FSW joints are mainly derived from the Orowan strengthening and grain boundary strengthening caused by secondary coherent Al3(Sc,Zr) nano-particles (20-40 nm). For new Al-Mg-Mn-Sc-Zr alloy, the positive effect from secondary Al3(Sc, Zr) particles in the base metal can be better preserved in FSW joint than in TIG welded joint.

  17. Inhibition Shapes Response Selectivity in the Inferior Colliculus by Gain Modulation

    Directory of Open Access Journals (Sweden)

    Joshua X Gittelman

    2012-09-01

    Full Text Available Pharmacological block of inhibition is often used to determine if inhibition contributes to spike selectivity, in which a preferred stimulus evokes more spikes than a null stimulus. When inhibitory block reduces spike selectivity, a common interpretation is that differences between the preferred- and null-evoked inhibitions created the selectivity from less-selective excitatory inputs. In models based on empirical properties of cells from the inferior colliculus of awake bats, we show that inhibitory differences are not required. Instead, inhibition can enhance spike selectivity by changing the gain, the ratio of output spikes to input current. Within the model, we made preferred stimuli that evoked more spikes than null stimuli using five distinct synaptic mechanisms. In two cases, synaptic selectivity (the differences between the preferred and null inputs was entirely excitatory, and in two it was entirely inhibitory. In each case, blocking inhibition eliminated spike selectivity. Thus, observing spike rates following inhibitory block did not distinguish among the cases where synaptic selectivity was entirely excitatory or inhibitory. We then did the same modeling experiment using empirical synaptic conductances derived from responses to preferred and null sounds. In most cases, inhibition in the model enhanced spike selectivity mainly by gain modulation and firing rate reduction. Sometimes, inhibition reduced the null gain to zero, eliminating null-evoked spikes. In some cases, inhibition increased the preferred gain more than the null gain, enhancing the difference between the preferred- and null-evoked spikes. Finally, inhibition kept firing rates low. When selectivity is quantified by the selectivity index (SI, the ratio of the difference to the sum of the spikes evoked by the preferred and null stimuli, inhibitory block reduced the SI by increasing overall firing rates. These results are consistent with inhibition shaping spike

  18. Excitatory and inhibitory projections in parallel pathways from the inferior colliculus to the auditory thalamus

    Directory of Open Access Journals (Sweden)

    Jeffrey Garrett Mellott

    2014-11-01

    Full Text Available Individual subdivisions of the medial geniculate body (MG receive a majority of their ascending inputs from 1 or 2 subdivisions of the inferior colliculus (IC. This establishes parallel pathways that provide a model for understanding auditory projections from the IC through the MG and on to auditory cortex. A striking discovery about the tectothalamic circuit was identification of a substantial GABAergic component. Whether GABAergic projections match the parallel pathway organization has not been examined. We asked whether the parallel pathway concept is reflected in guinea pig tectothalamic pathways and to what degree GABAergic cells contribute to each pathway. We deposited retrograde tracers into individual MG subdivisions (ventral, MGv; medial, MGm; dorsal, MGd; suprageniculate, MGsg to label tectothalamic cells and used immunochemistry to identify GABAergic cells. The MGv receives most of its IC input (~75% from the IC central nucleus (ICc; MGd and MGsg receive most of their input (~70% from IC dorsal cortex (ICd; and MGm receives substantial input from both ICc (~40% and IC lateral cortex (~40%. Each MG subdivision receives additional input (up to 32% from non-dominant IC subdivisions, suggesting cross-talk between the pathways. The proportion of GABAergic cells in each pathway depended on the MG subdivision. GABAergic cells formed ~20% of IC inputs to MGv or MGm, ~11% of inputs to MGd, and 4% of inputs to MGsg. Thus, non-GABAergic (i.e., glutamatergic cells are most numerous in each pathway with GABAergic cells contributing to different extents. Despite smaller numbers of GABAergic cells, their distributions across IC subdivisions mimicked the parallel pathways. Projections outside the dominant pathways suggest opportunities for excitatory and inhibitory crosstalk. The results demonstrate parallel tectothalamic pathways in guinea pigs and suggest numerous opportunities for excitatory and inhibitory interactions within and between pathways.

  19. A computational model of inferior colliculus responses to amplitude modulated sounds in young and aged rats

    Directory of Open Access Journals (Sweden)

    Cal Francis Rabang

    2012-11-01

    Full Text Available The inferior colliculus (IC receives ascending excitatory and inhibitory inputs from multiple sources, but how these auditory inputs converge to generate IC spike patterns is poorly understood. Simulating patterns of in vivo spike train data from cellular and synaptic models creates a powerful framework to identify factors that contribute to changes in IC responses, such as those resulting in age-related loss of temporal processing. A conductance-based single neuron IC model was constructed, and its responses were compared to those observed during in vivo IC recordings in rats. IC spike patterns were evoked using amplitude-modulated (AM tone or noise carriers at 20-40 dB above threshold and were classified as low-pass, band-pass, band-reject, all-pass, or complex based on their rate modulation transfer function (rMTF tuning shape. Their temporal modulation transfer functions (tMTFs were also measured. These spike patterns provided experimental measures of rate, vector strength and firing pattern for comparison with model outputs. Patterns of excitatory and inhibitory synaptic convergence to IC neurons were based on anatomical studies and generalized input tuning for modulation frequency. Responses of modeled ascending inputs were derived from experimental data from previous studies. Adapting and sustained IC intrinsic models were created, with adaptation created via calcium-activated potassium currents. Short-term synaptic plasticity was incorporated into the model in the form of synaptic depression, which was shown to have a substantial effect on the magnitude and time course of the IC response. The most commonly observed IC response subtypes were recreated and enabled dissociation of inherited response properties from those that were generated in IC. Furthermore, the model was used to make predictions about the consequences of reduction in inhibition for age-related loss of temporal processing due to a reduction in GABA seen anatomically with

  20. Representation of interaural time difference in the central nucleus of the barn owl's inferior colliculus.

    Science.gov (United States)

    Wagner, H; Takahashi, T; Konishi, M

    1987-10-01

    This paper investigates the role of the central nucleus of the barn owl's inferior colliculus in determination of the sound-source azimuth. The central nucleus contains many neurons that are sensitive to interaural time difference (ITD), the cue for azimuth in the barn owl. The response of these neurons varies in a cyclic manner with the ITD of a tone or noise burst. Response maxima recur at integer multiples of the period of the stimulating tone, or, if the stimulus is noise, at integer multiples of the period corresponding to the neuron's best frequency. Such neurons can signal, by means of their relative spike rate, the phase difference between the sounds reaching the left and right ears. Since an interaural phase difference corresponds to more than one ITD, these neurons represent ITD ambiguously. We call this phenomenon phase ambiguity. The central nucleus is tonotopically organized and its neurons are narrowly tuned to frequency. Neurons in an array perpendicular to isofrequency laminae form a physiological and anatomical unit; only one ITD, the array-specific ITD, activates all neurons in an array at the same relative level. We, therefore, may say that, in the central nucleus, an ITD is conserved in an array of neurons. Array-specific ITDs are mapped and encompass the entire auditory space of the barn owl. Individual space-specific neurons of the external nucleus, which receive inputs from a wide range of frequency channels (Knudsen and Konishi, 1978), are selective for a unique ITD. Space-specific neurons do not show phase ambiguity when stimulated with noise (Takahashi and Konishi, 1986). Space-specific neurons receive inputs from arrays that are selective for the same ITD. The collective response of the neurons in an array may be the basis for the absence of phase ambiguity in space-specific neurons.

  1. Projections of the cochlear nuclei and nucleus laminaris to the inferior colliculus of the barn owl.

    Science.gov (United States)

    Takahashi, T T; Konishi, M

    1988-08-08

    The barn owl determines the directions from which sounds emanate by computing the interaural differences in the timing and intensity of sounds. These cues for sound localization are processed in independent channels originating at nucleus magnocellularis (NM) and nucleus angularis (NA), the cochlear nuclei. The cells of NM are specialized for encoding the phase of sounds in the ipsilateral ear. The cells of NA are specialized for encoding the intensity of sounds in the ipsilateral ear. NM projects solely, bilaterally, and tonotopically to nucleus laminaris (NL). NL and NA project to largely nonoverlapping zones in the central nucleus of the inferior colliculus (ICc), thus forming hodological subdivisions in which time and intensity information may be processed. The terminal field of NL occupies a discrete zone in the rostromedial portion of the contralateral ICc, which we have termed the "core" of ICc. The terminal field of NA surrounds the core of ICc and thus forms a "shell" around it. The projection from NL to the core conserves tonotopy. Low-frequency regions of NL project to the dorsal portions of the core whereas higher-frequency regions project to more ventral portions. This innervation pattern is consistent with earlier physiological studies of tonotopy. Physiological studies have also suggested that NL and the core of ICs contain a representation of the location of a sound source along the horizontal axis. Our data suggest that the projection from NL to the core preserves spatiotopy. Thus, the dorsal portion of NL on the left, which contains a representation of eccentric loci in the right hemifield, innervates the area of the right ICc core that represents eccentric right loci. The more ventral portion of the left NL, which represents loci close to the vertical meridian, innervates the more rostral portions of the right core, which also represents loci near the vertical meridian.

  2. Frequency response areas in the inferior colliculus: nonlinearity and binaural interaction

    Science.gov (United States)

    Yu, Jane J.; Young, Eric D.

    2013-01-01

    The tuning, binaural properties, and encoding characteristics of neurons in the central nucleus of the inferior colliculus (CNIC) were investigated to shed light on nonlinearities in the responses of these neurons. Results were analyzed for three types of neurons (I, O, and V) in the CNIC of decerebrate cats. Rate responses to binaural stimuli were characterized using a 1st- plus 2nd-order spectral integration model. Parameters of the model were derived using broadband stimuli with random spectral shapes (RSS). This method revealed four characteristics of CNIC neurons: (1) Tuning curves derived from broadband stimuli have fixed (i. e., level tolerant) bandwidths across a 50–60 dB range of sound levels; (2) 1st-order contralateral weights (particularly for type I and O neurons) were usually larger in magnitude than corresponding ipsilateral weights; (3) contralateral weights were more important than ipsilateral weights when using the model to predict responses to untrained noise stimuli; and (4) 2nd-order weight functions demonstrate frequency selectivity different from that of 1st-order weight functions. Furthermore, while the inclusion of 2nd-order terms in the model usually improved response predictions related to untrained RSS stimuli, they had limited impact on predictions related to other forms of filtered broadband noise [e. g., virtual-space stimuli (VS)]. The accuracy of the predictions varied considerably by response type. Predictions were most accurate for I neurons, and less accurate for O and V neurons, except at the lowest stimulus levels. These differences in prediction performance support the idea that type I, O, and V neurons encode different aspects of the stimulus: while type I neurons are most capable of producing linear representations of spectral shape, type O and V neurons may encode spectral features or temporal stimulus properties in a manner not easily explained with the low-order model. Supported by NIH grant DC00115. PMID:23675323

  3. Effect of background noise on neuronal coding of interaural level difference cues in rat inferior colliculus

    Science.gov (United States)

    Mokri, Yasamin; Worland, Kate; Ford, Mark; Rajan, Ramesh

    2015-01-01

    Humans can accurately localize sounds even in unfavourable signal-to-noise conditions. To investigate the neural mechanisms underlying this, we studied the effect of background wide-band noise on neural sensitivity to variations in interaural level difference (ILD), the predominant cue for sound localization in azimuth for high-frequency sounds, at the characteristic frequency of cells in rat inferior colliculus (IC). Binaural noise at high levels generally resulted in suppression of responses (55.8%), but at lower levels resulted in enhancement (34.8%) as well as suppression (30.3%). When recording conditions permitted, we then examined if any binaural noise effects were related to selective noise effects at each of the two ears, which we interpreted in light of well-known differences in input type (excitation and inhibition) from each ear shaping particular forms of ILD sensitivity in the IC. At high signal-to-noise ratios (SNR), in most ILD functions (41%), the effect of background noise appeared to be due to effects on inputs from both ears, while for a large percentage (35.8%) appeared to be accounted for by effects on excitatory input. However, as SNR decreased, change in excitation became the dominant contributor to the change due to binaural background noise (63.6%). These novel findings shed light on the IC neural mechanisms for sound localization in the presence of continuous background noise. They also suggest that some effects of background noise on encoding of sound location reported to be emergent in upstream auditory areas can also be observed at the level of the midbrain. PMID:25865218

  4. FIRING PROPERTY OF INFERIOR COLLICULUS NEURONS AFFECTED BY FMR1 GENE MUTATION

    Institute of Scientific and Technical Information of China (English)

    Brittany Mott; SUN Wei

    2014-01-01

    Fragile X syndrome is the most common form of inherited mental retardation affecting up to 1 in 4000 individuals. The syn-drome is induced by a mutation in the FMR1 gene, causing a deficiency in its gene by-product FMRP. Impairment in the nor-mal functioning of FMRP leads to learning and memory deficits and heightened sensitivity to sensory stimuli, including sound (hyperacusis). The molecular basis of fragile X syndrome is thoroughly understood;however, the neural mechanisms underly-ing hyperacusis have not yet been determined. As the inferior colliculus (IC) is the principal midbrain nucleus of the auditory pathway, the current study addresses the questions underlying the neural mechanism of hyperacusis within the IC of fragile X mice. Acute experiments were performed in which electrophysiological recordings of the IC in FMR1-KO and WT mice were measured. Results showed that Q-values for WT were significantly larger than that of FMR-1 KO mice, indicating that WT mice exhibit sharper tuning curves than FMR1-KO mice. We also found the ratio of the monotonic neurons in the KO mice was much higher than the WT mice. These results suggest that lack of FMRP in the auditory system affects the developmental maturation and function of structures within the auditory pathway, and in this case specifically the IC. The dysfunction ob-served within the auditory neural pathway and in particular the IC may be related to the increased susceptibility to sound as seen in individuals with fragile X syndrome. Our study may help on understanding the mechanisms of the fragile X syndrome and hyperacusis.

  5. Immunocytochemical profiles of inferior colliculus neurons in the rat and their changes with aging

    Directory of Open Access Journals (Sweden)

    Ladislav eOuda

    2012-09-01

    Full Text Available The inferior colliculus (IC plays a strategic role in the central auditory system in relaying and processing acoustical information, and therefore its age-related changes may significantly influence the quality of the auditory function. A very complex processing of acoustical stimuli occurs in the IC, as supported also by the fact that the rat IC contains more neurons than all other subcortical auditory structures combined. GABAergic neurons, which predominantly co-express parvalbumin, are present in the central nucleus of the IC in large numbers and to a lesser extent in the dorsal and external/lateral cortices of the IC. On the other hand, calbindin and calretinin are prevalent in the dorsal and external cortices of the IC, with only a few positive neurons in the central nucleus. The relationship between calbindin and calretinin expression in the IC and any neurotransmitter system has not yet been well established, but the distribution and morphology of the immunoreactive neurons suggest that they are at least partially non-GABAergic cells. The expression of glutamate decarboxylase (a key enzyme for GABA synthesis and calcium binding proteins in the IC of rats undergoes pronounced changes with aging that involve mostly a decline in protein expression and a decline in the number of immunoreactive neurons. Similar age-related changes in glutamate decarboxylase, calbindin and calretinin expression are present in the IC of two rat strains with differently preserved inner ear function up to late senescence (Long-Evans and Fischer 344, which suggests that these changes do not depend exclusively on peripheral deafferentation but are, at least partially, of central origin. These changes may be associated with the age-related deterioration in the processing of the temporal parameters of acoustical stimuli, which is not correlated with hearing threshold shifts, and therefore may contribute to central presbycusis.

  6. Effect of background noise on neuronal coding of interaural level difference cues in rat inferior colliculus.

    Science.gov (United States)

    Mokri, Yasamin; Worland, Kate; Ford, Mark; Rajan, Ramesh

    2015-07-01

    Humans can accurately localize sounds even in unfavourable signal-to-noise conditions. To investigate the neural mechanisms underlying this, we studied the effect of background wide-band noise on neural sensitivity to variations in interaural level difference (ILD), the predominant cue for sound localization in azimuth for high-frequency sounds, at the characteristic frequency of cells in rat inferior colliculus (IC). Binaural noise at high levels generally resulted in suppression of responses (55.8%), but at lower levels resulted in enhancement (34.8%) as well as suppression (30.3%). When recording conditions permitted, we then examined if any binaural noise effects were related to selective noise effects at each of the two ears, which we interpreted in light of well-known differences in input type (excitation and inhibition) from each ear shaping particular forms of ILD sensitivity in the IC. At high signal-to-noise ratios (SNR), in most ILD functions (41%), the effect of background noise appeared to be due to effects on inputs from both ears, while for a large percentage (35.8%) appeared to be accounted for by effects on excitatory input. However, as SNR decreased, change in excitation became the dominant contributor to the change due to binaural background noise (63.6%). These novel findings shed light on the IC neural mechanisms for sound localization in the presence of continuous background noise. They also suggest that some effects of background noise on encoding of sound location reported to be emergent in upstream auditory areas can also be observed at the level of the midbrain.

  7. NADPH-diaphorase-positive neurons in the human inferior colliculus: morphology, distribution and clinical implications.

    Science.gov (United States)

    Hinova-Palova, D; Landzhov, B; Dzhambazova, E; Edelstein, L; Minkov, M; Fakih, K; Minkov, R; Paloff, A; Ovtscharoff, W

    2017-05-01

    Using the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) reaction with nitroblue tetrazolium, we provided a detailed investigation of the distribution, dimensional characteristics and morphology of NADPH-d-positive neurons in the three main subdivisions of the human inferior colliculus (IC): central nucleus, pericentral nucleus, and external nucleus. In accordance with their perikaryal diameter, dendritic and axonal morphology, these neurons were categorized as large (averaging up to 45 μm in diameter), medium (20-30 µm), small (13-16 µm) and very small (7-10 µm). Their morphological differences could contribute to varying functionality and processing capacity. Our results support the hypothesis that large and medium NADPH-d-positive cells represent projection neurons, while the small cells correspond to interneurons. Heretofore, the very small NADPH-d-positive neurons have not been described in any species. Their functions-and if they are, indeed, the smallest neurons in the IC of humans-remain to be clarified. Owing to their location, we posit that they are interneurons that connect the large NADPH-d-positive neurons and thereby serve as an anatomical substrate for information exchange and processing before feeding forward to higher brain centers. Our results also suggest that the broad distribution of nitric oxide (NO) synthesis in the human IC is closely tied to the neuromodulatory action of NO on collicular neurotransmitters such as GABA and glutamate, and to calcium-binding proteins such as parvalbumin. A deeper understanding of the relationship between NADPH-d-positive fibers in all IC connections and their co-localization with other neurotransmitters and calcium-binding proteins will assist in better defining the function of NO in the context of its interplay with the cerebral cortex, the sequelae of the aging process and neurodegenerative disorders.

  8. Analysis of time and space invariance of BOLD responses in the rat visual system

    DEFF Research Database (Denmark)

    Bailey, Christopher; Sanganahalli, Basavaraju G; Herman, Peter

    2013-01-01

    superior colliculus (SC) and primary visual cortex (V1) in rat brain--regions with different basal blood flow and energy demand. Our goal was to assess neurovascular coupling in V1 and SC as reflected by temporal/spatial variances of impulse response functions (IRFs) and assess, if any, implications...

  9. Spectral embedding based probabilistic boosting tree (ScEPTre): classifying high dimensional heterogeneous biomedical data.

    Science.gov (United States)

    Tiwari, Pallavi; Rosen, Mark; Reed, Galen; Kurhanewicz, John; Madabhushi, Anant

    2009-01-01

    The major challenge with classifying high dimensional biomedical data is in identifying the appropriate feature representation to (a) overcome the curse of dimensionality, and (b) facilitate separation between the data classes. Another challenge is to integrate information from two disparate modalities, possibly existing in different dimensional spaces, for improved classification. In this paper, we present a novel data representation, integration and classification scheme, Spectral Embedding based Probabilistic boosting Tree (ScEPTre), which incorporates Spectral Embedding (SE) for data representation and integration and a Probabilistic Boosting Tree classifier for data classification. SE provides an alternate representation of the data by non-linearly transforming high dimensional data into a low dimensional embedding space such that the relative adjacencies between objects are preserved. We demonstrate the utility of ScEPTre to classify and integrate Magnetic Resonance (MR) Spectroscopy (MRS) and Imaging (MRI) data for prostate cancer detection. Area under the receiver operating Curve (AUC) obtained via randomized cross validation on 15 prostate MRI-MRS studies suggests that (a) ScEPTre on MRS significantly outperforms a Haar wavelets based classifier, (b) integration of MRI-MRS via ScEPTre performs significantly better compared to using MRI and MRS alone, and (c) data integration via ScEPTre yields superior classification results compared to combining decisions from individual classifiers (or modalities).

  10. Contabilidad Financiera Superior

    OpenAIRE

    Ipiñazar Petralanda, Izaskun

    2013-01-01

    Duración (en horas): De 31 a 40 horas. Destinatario: Estudiante y Docente A través de este material se presentan las pautas necesarias para implementar un aprendizaje basado en problemas en la asignatura de Contabilidad Financiera Superior dentro de los temas “Constitución de S.A. y S.R.L.” (Tema 2), “Ampliaciones de Capital” (Tema 3) y “Reducciones de Capital” (Tema 4). En primer lugar se presentan las guías generales de la asignatura, y a continuación, las diferentes activida...

  11. Contabilidad Financiera Superior

    OpenAIRE

    Ipiñazar Petralanda, Izaskun

    2013-01-01

    Duración (en horas): De 31 a 40 horas. Destinatario: Estudiante y Docente A través de este material se presentan las pautas necesarias para implementar un aprendizaje basado en problemas en la asignatura de Contabilidad Financiera Superior dentro de los temas “Constitución de S.A. y S.R.L.” (Tema 2), “Ampliaciones de Capital” (Tema 3) y “Reducciones de Capital” (Tema 4). En primer lugar se presentan las guías generales de la asignatura, y a continuación, las diferentes activida...

  12. Sc20C60: a volleyballene

    Science.gov (United States)

    Wang, Jing; Ma, Hong-Man; Liu, Ying

    2016-06-01

    An exceptionally stable hollow cage containing 20 scandium atoms and 60 carbon atoms has been identified. This Sc20C60 molecular cluster has a Th point group symmetry and a volleyball-like shape that we refer to below as ``Volleyballene''. Electronic structure analysis shows that the formation of delocalized π bonds between Sc atoms and the neighboring pentagonal rings made of carbon atoms is crucial for stabilizing the cage structure. A relatively large HOMO-LUMO gap (~1.4 eV) was found. The results of vibrational frequency analysis and molecular dynamics simulations both demonstrate that this Volleyballene molecule is exceptionally stable.An exceptionally stable hollow cage containing 20 scandium atoms and 60 carbon atoms has been identified. This Sc20C60 molecular cluster has a Th point group symmetry and a volleyball-like shape that we refer to below as ``Volleyballene''. Electronic structure analysis shows that the formation of delocalized π bonds between Sc atoms and the neighboring pentagonal rings made of carbon atoms is crucial for stabilizing the cage structure. A relatively large HOMO-LUMO gap (~1.4 eV) was found. The results of vibrational frequency analysis and molecular dynamics simulations both demonstrate that this Volleyballene molecule is exceptionally stable. Electronic supplementary information (ESI) available: Sc20C60: a Volleyballene_SI. See DOI: 10.1039/c5nr07784b

  13. Statistics of superior records

    Science.gov (United States)

    Ben-Naim, E.; Krapivsky, P. L.

    2013-08-01

    We study statistics of records in a sequence of random variables. These identical and independently distributed variables are drawn from the parent distribution ρ. The running record equals the maximum of all elements in the sequence up to a given point. We define a superior sequence as one where all running records are above the average record expected for the parent distribution ρ. We find that the fraction of superior sequences SN decays algebraically with sequence length N, SN˜N-β in the limit N→∞. Interestingly, the decay exponent β is nontrivial, being the root of an integral equation. For example, when ρ is a uniform distribution with compact support, we find β=0.450265. In general, the tail of the parent distribution governs the exponent β. We also consider the dual problem of inferior sequences, where all records are below average, and find that the fraction of inferior sequences IN decays algebraically, albeit with a different decay exponent, IN˜N-α. We use the above statistical measures to analyze earthquake data.

  14. Frenillo labial superior doble

    Directory of Open Access Journals (Sweden)

    Carlos Albornoz López del Castillo

    Full Text Available El frenillo labial superior doble no sindrómico es una anomalía del desarrollo que no hemos encontrado reportada en la revisión bibliográfica realizada. Se presenta una niña de 11 años de edad que fue remitida al servicio de Cirugía Maxilofacial del Hospital "Eduardo Agramonte Piña", de Camagüey, por presentar un frenillo labial superior doble de baja inserción. Se describen los síntomas clínicos asociados a esta anomalía y el tratamiento quirúrgico utilizado para su solución: una frenectomía y plastia sobre la banda muscular frénica anormal que provocaba exceso de tejido en la mucosa labial. Consideramos muy interesante la descripción de este caso, por no haber encontrado reporte similar en la literatura revisada.

  15. Anatomical differences in the human inferior colliculus relate to the perceived valence of musical consonance and dissonance.

    Science.gov (United States)

    Fritz, Thomas Hans; Renders, Wiske; Müller, Karsten; Schmude, Paul; Leman, Marc; Turner, Robert; Villringer, Arno

    2013-10-01

    Helmholtz himself speculated about a role of the cochlea in the perception of musical dissonance. Here we indirectly investigated this issue, assessing the valence judgment of musical stimuli with variable consonance/dissonance and presented diotically (exactly the same dissonant signal was presented to both ears) or dichotically (a consonant signal was presented to each ear--both consonant signals were rhythmically identical but differed by a semitone in pitch). Differences in brain organisation underlying inter-subject differences in the percept of dichotically presented dissonance were determined with voxel-based morphometry. Behavioral results showed that diotic dissonant stimuli were perceived as more unpleasant than dichotically presented dissonance, indicating that interactions within the cochlea modulated the valence percept during dissonance. However, the behavioral data also suggested that the dissonance percept did not depend crucially on the cochlea, but also occurred as a result of binaural integration when listening to dichotic dissonance. These results also showed substantial between-participant variations in the valence response to dichotic dissonance. These differences were in a voxel-based morphometry analysis related to differences in gray matter density in the inferior colliculus, which strongly substantiated a key role of the inferior colliculus in consonance/dissonance representation in humans.

  16. Recrystallization and Morphology of Microstructure in Al-Sc Alloys

    Institute of Scientific and Technical Information of China (English)

    Zhang Jun; Zhang Zonghua

    2007-01-01

    Minor addition of Sc to aluminum results in the rapid precipitation of homogeneously distributed Al3Sc dispersoids. The presence of Al3Sc dispersoids is more effective recrystallization inhibitors. Our work established the precipitation of homogeneously distributed Al3Sc dispersoids, which are coherent with the matrix, have the L12 structure. It was also established that the addition of Sc was effective in improving the recrystallization resistance.

  17. K2SC: K2 Systematics Correction

    Science.gov (United States)

    Aigrain, Suzanne; Parviainen, Hannu; Pope, Benjamin

    2016-05-01

    K2SC (K2 Systematics Correction) models instrumental systematics and astrophysical variability in light curves from the K2 mission. It enables the user to remove both position-dependent systematics and time-dependent variability (e.g., for transit searches) or to remove systematics while preserving variability (for variability studies). K2SC automatically computes estimates of the period, amplitude and evolution timescale of the variability for periodic variables and can be run on ASCII and FITS light curve files. Written in Python, this pipeline requires NumPy, SciPy, MPI4Py, Astropy (ascl:1304.002), and George (ascl:1511.015).

  18. Norma Audio Revo SC-/PA-150

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Norma audio是意大利一间顶级HI-Fi音响器材生产商。这款IRevo SC-2/PA-150为正是公司旗下的一款高端型号产品。其中,Revo SC-2前置放大器的放大电路以低噪音、高速和宽频作为设计重点,能反映出音频信号中的每一个细节。

  19. Spatial selectivity and binaural responses in the inferior colliculus of the great horned owl.

    Science.gov (United States)

    Volman, S F; Konishi, M

    1989-09-01

    In this study we have investigated the processing of auditory cues for sound localization in the great horned owl (Bubo virginianus). Previous studies have shown that the barn owl, whose ears are asymmetrically oriented in the vertical plane, has a 2-dimensional, topographic representation of auditory space in the external division of the inferior colliculus (ICx). As in the barn owl, the great horned owl's ICx is anatomically distinct and projects to the optic tectum. Neurons in ICx respond over only a small range of azimuths (mean = 32 degrees), and azimuth is topographically mapped. In contrast to the barn owl, the great horned owl has bilaterally symmetrical ears and its receptive fields are not restricted in elevation. The binaural cues available for sound localization were measured both with cochlear microphonic recordings and with a microphone attached to a probe tube in the auditory canal. Interaural time disparity (ITD) varied monotonically with azimuth. Interaural intensity differences (IID) also changed with azimuth, but the largest IIDs were less than 15 dB, and the variation was not monotonic. Neither ITD nor IID varied systematically with changes in the vertical position of a sound source. We used dichotic stimulation to determine the sensitivity of ICx neurons to these binaural cues. Best ITD of ICx units was topographically mapped and strongly correlated with receptive-field azimuth. The width of ITD tuning curves, measured at 50% of the maximum response, averaged 72 microseconds. All ICx neurons responded only to binaural stimulation and had nonmonotonic IID tuning curves. Best IID was weakly, but significantly, correlated with best ITD (r = 0.39, p less than 0.05). The IID tuning curves, however, were broad (mean 50% width = 24 dB), and 67% of the units had best IIDs within 5 dB of 0 dB IID. ITD tuning was sensitive to variations in IID in the direction opposite to that expected for time-intensity trading, but the magnitude of this effect was only

  20. Measurement of the SC magnetic field

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    The 3.5-metre-arm carrying 100 Hall plates used for the measurmeent of the SC magnetic field. The arm rotates in a horizontal plane, its positioning and the data read-out are controlled by an on-line computer.

  1. Magnet measuring equipment of SC2

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    Checking the positioning of the magnet measuring equipment installed between the poles of SC2. The steel structure in front of the magnet is designed to house the rotary condenser and to shield it from the stray magnetic field of the accelerator.

  2. Magnet measuring equipment of SC2

    CERN Multimedia

    1974-01-01

    Checking the positioning of the magnet measuring equipment installed between the poles of SC2. The steel structure in front of the magnet is designed to house the rotary condenser and to shield it from the stray magnetic field of the accelerator. On the left, Marinus van Gulik. (See Photo Archive 7402005 and Annual Report 1974, p. 44.)

  3. The Synchrocyclotron (SC) in building 300

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    The red magnet of CERN's first accelerator, the Synchrocyclotron (SC), has occupied a large part of Hall 300 since it was installed in the late 1950s. The remaining part of the 300-square-metre building has been used as a storage room since the accelerator was shut down in 1990. Now a public exhibition will breathe new life into the hall.

  4. Knowledge insufficient: the management of haemoglobin SC disease.

    Science.gov (United States)

    Pecker, Lydia H; Schaefer, Beverly A; Luchtman-Jones, Lori

    2017-02-01

    Although haemoglobin SC (HbSC) accounts for 30% of sickle cell disease (SCD) in the United States and United Kingdom, evidence-based guidelines for genotype specific management are lacking. The unique pathology of HbSC disease is complex, characterized by erythrocyte dehydration, intracellular sickling and increased blood viscosity. The evaluation and treatment of patients with HbSC is largely inferred from studies of SCD consisting mostly of haemoglobin SS (HbSS) patients. These studies are underpowered to allow definitive conclusions about HbSC. We review the pathophysiology of HbSC disease, including known and potential differences between HbSS and HbSC, and highlight knowledge gaps in HbSC disease management. Clinical and translational research is needed to develop targeted treatments and to validate management recommendations for efficacy, safety and impact on quality of life for people with HbSC. © 2016 John Wiley & Sons Ltd.

  5. Sobredentadura total superior implantosoportada

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.

  6. Precipitation hardening in ternary alloys of the Al-Sc-Cu and Al-Sc-Si systems

    Energy Technology Data Exchange (ETDEWEB)

    Kharakterova, M.L.; Eskin, D.G.; Toropova, L.S. (Russian Academy of Sciences, Moscow (Russian Federation). A.A. Baikov Inst. of Metallurgy)

    1994-07-01

    The processes of precipitation hardening in cast ternary alloys of the Al-Sc-Cu and Al-Sc-Si systems were studied in the temperature range of aging from 100 to 450 C and at exposures to 200 h. It was shown that the CuAl[sub 2] and ScAl[sub 3] phases were involved in the process of aging in ternary Al-Sc-Cu alloys, and the Si and V (AlSiSc) phases, in ternary Al-Sc-Si alloys with excess silicon in a supersaturated solid solution. The V phase was for the first time revealed as the hardening phase in aluminum alloys.

  7. LHCb Data Replication During SC3

    CERN Multimedia

    Smith, A

    2006-01-01

    LHCb's participation in LCG's Service Challenge 3 involves testing the bulk data transfer infrastructure developed to allow high bandwidth distribution of data across the grid in accordance with the computing model. To enable reliable bulk replication of data, LHCb's DIRAC system has been integrated with gLite's File Transfer Service middleware component to make use of dedicated network links between LHCb computing centres. DIRAC's Data Management tools previously allowed the replication, registration and deletion of files on the grid. For SC3 supplementary functionality has been added to allow bulk replication of data (using FTS) and efficient mass registration to the LFC replica catalog.Provisional performance results have shown that the system developed can meet the expected data replication rate required by the computing model in 2007. This paper details the experience and results of integration and utilisation of DIRAC with the SC3 transfer machinery.

  8. Reduced-Latency SC Polar Decoder Architectures

    CERN Document Server

    Zhang, Chuan; Parhi, Keshab K

    2011-01-01

    Polar codes have become one of the most favorable capacity achieving error correction codes (ECC) along with their simple encoding method. However, among the very few prior successive cancellation (SC) polar decoder designs, the required long code length makes the decoding latency high. In this paper, conventional decoding algorithm is transformed with look-ahead techniques. This reduces the decoding latency by 50%. With pipelining and parallel processing schemes, a parallel SC polar decoder is proposed. Sub-structure sharing approach is employed to design the merged processing element (PE). Moreover, inspired by the real FFT architecture, this paper presents a novel input generating circuit (ICG) block that can generate additional input signals for merged PEs on-the-fly. Gate-level analysis has demonstrated that the proposed design shows advantages of 50% decoding latency and twice throughput over the conventional one with similar hardware cost.

  9. Single chain Fab (scFab fragment

    Directory of Open Access Journals (Sweden)

    Brenneis Mariam

    2007-03-01

    Full Text Available Abstract Background The connection of the variable part of the heavy chain (VH and and the variable part of the light chain (VL by a peptide linker to form a consecutive polypeptide chain (single chain antibody, scFv was a breakthrough for the functional production of antibody fragments in Escherichia coli. Being double the size of fragment variable (Fv fragments and requiring assembly of two independent polypeptide chains, functional Fab fragments are usually produced with significantly lower yields in E. coli. An antibody design combining stability and assay compatibility of the fragment antigen binding (Fab with high level bacterial expression of single chain Fv fragments would be desirable. The desired antibody fragment should be both suitable for expression as soluble antibody in E. coli and antibody phage display. Results Here, we demonstrate that the introduction of a polypeptide linker between the fragment difficult (Fd and the light chain (LC, resulting in the formation of a single chain Fab fragment (scFab, can lead to improved production of functional molecules. We tested the impact of various linker designs and modifications of the constant regions on both phage display efficiency and the yield of soluble antibody fragments. A scFab variant without cysteins (scFabΔC connecting the constant part 1 of the heavy chain (CH1 and the constant part of the light chain (CL were best suited for phage display and production of soluble antibody fragments. Beside the expression system E. coli, the new antibody format was also expressed in Pichia pastoris. Monovalent and divalent fragments (DiFabodies as well as multimers were characterised. Conclusion A new antibody design offers the generation of bivalent Fab derivates for antibody phage display and production of soluble antibody fragments. This antibody format is of particular value for high throughput proteome binder generation projects, due to the avidity effect and the possible use of

  10. The SC gets ready for visitors

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    Hall 300, which houses the Synchrocyclotron (SC), CERN’s first accelerator, is getting ready to host a brand-new exhibition. The site will be one of the stops on the new visit itineraries that will be inaugurated for the 2013 CERN Open Day.   The Synchrocyclotron through the years. Just as it did in the late 1950s, when the accelerator was first installed, the gigantic red structure of the Synchrocyclotron's magnet occupies a large part of the 300-square-metre hall. “We have completed the first phase of the project that will give the SC a new lease of life,” says Marco Silari, the project leader and a member of CERN’s Radiation Protection Group. “We have removed all the equipment that was not an integral part of the accelerator. The hall is now ready for the civil-engineering work that will precede the installation of the exhibition.” The SC was witness to a big part of the history of CERN. The accelerator produced ...

  11. ViSC Social Competence Program.

    Science.gov (United States)

    Strohmeier, Dagmar; Hoffmann, Christine; Schiller, Eva-Maria; Stefanek, Elisabeth; Spiel, Christiane

    2012-01-01

    The ViSC Social Competence Program has been implemented in Austrian schools within the scope of a national strategy plan, Together Against Violence. The program is a primary preventive program designed for grades 5 to 8. The prevention of aggression and bullying is defined as a school development task, and the initial implementation of the program lasts one school year. The program consists of universal and specific actions that are implemented through in-school teacher training and a class project for students. The program was evaluated with a randomized intervention control group design. Data were collected from teachers and students. Results suggest that the program reduces aggression in schools.

  12. Measurement of (43)Sc and (44)Sc production cross-section with an 18MeV medical PET cyclotron.

    Science.gov (United States)

    Carzaniga, Tommaso Stefano; Auger, Martin; Braccini, Saverio; Bunka, Maruta; Ereditato, Antonio; Nesteruk, Konrad Pawel; Scampoli, Paola; Türler, Andreas; van der Meulen, Nicholas

    2017-11-01

    (43)Sc and (44)Sc are positron emitter radionuclides that, in conjunction with the β(-) emitter (47)Sc, represent one of the most promising possibilities for theranostics in nuclear medicine. Their availability in suitable quantity and quality for medical applications is an open issue and their production with medical cyclotrons represents a scientific and technological challenge. For this purpose, an accurate knowledge of the production cross sections is mandatory. In this paper, we report on the cross section measurement of the reactions (43)Ca(p,n)(43)Sc, (44)Ca(p,2n) (43)Sc, (46)Ti(p,α)(43)Sc, and (44)Ca(p,n)(44)Sc at the Bern University Hospital cyclotron. A study of the production yield and purity performed by using commercially available enriched target materials is also presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. BOOK REVIEW: Assessing Sc1 for GCSE

    Science.gov (United States)

    Reynolds, H.

    2000-01-01

    It is well known that investigations that `fit' the National Curriculum or examination board criteria are few in number. The fair testing emphasis means that pupils all over the country are finding out what affects the rate of a chemical reaction, the rate of photosynthesis or, in the case of Physics, the resistance of a wire. This book focuses on nine of the most common Sc1 investigations and how to prepare for them, manage and assess them. The author, a GCSE examiner, has turned his expertise into a handbook for improving Sc1 performance in the classroom. He has produced a book that would be extremely useful to both newly qualified teachers and experienced teachers. The first aim of the book, however, is to explain the requirements of Sc1. This is done comprehensively with examples of what the jargon means in practice. By breaking down the elements of planning, obtaining evidence, analysing evidence and evaluating, it is easy to see the subtleties of the mark descriptors. At first glance there seems to be little difference between the type of scientific knowledge needed for planning at level 6 and level 8. However, the level 8 statement specifies `detailed' scientific knowledge and understanding, which would mean a student should use equations from physics or symbolic chemical equations to support their arguments. One of the most useful sections in the book details the marking problems that can arise with some investigations. For example, in an investigation into electromagnets it is difficult for students to provide sufficient relevant scientific theory to satisfy the requirements of planning at level 6. One of the problems with Sc1 is that certain requirements, such as graph plotting, are difficult for many students. This book provides exercises that can be given to students to improve those skills. Each of the nine investigations is covered in great detail. Each investigation begins with an introduction detailing the rationale for choosing it, whether students

  14. Passive stimulation and behavioral training differentially transform temporal processing in the inferior colliculus and primary auditory cortex.

    Science.gov (United States)

    Vollmer, Maike; Beitel, Ralph E; Schreiner, Christoph E; Leake, Patricia A

    2017-01-01

    In profoundly deaf cats, behavioral training with intracochlear electric stimulation (ICES) can improve temporal processing in the primary auditory cortex (AI). To investigate whether similar effects are manifest in the auditory midbrain, ICES was initiated in neonatally deafened cats either during development after short durations of deafness (8 wk of age) or in adulthood after long durations of deafness (≥3.5 yr). All of these animals received behaviorally meaningless, "passive" ICES. Some animals also received behavioral training with ICES. Two long-deaf cats received no ICES prior to acute electrophysiological recording. After several months of passive ICES and behavioral training, animals were anesthetized, and neuronal responses to pulse trains of increasing rates were recorded in the central (ICC) and external (ICX) nuclei of the inferior colliculus. Neuronal temporal response patterns (repetition rate coding, minimum latencies, response precision) were compared with results from recordings made in the AI of the same animals (Beitel RE, Vollmer M, Raggio MW, Schreiner CE. J Neurophysiol 106: 944-959, 2011; Vollmer M, Beitel RE. J Neurophysiol 106: 2423-2436, 2011). Passive ICES in long-deaf cats remediated severely degraded temporal processing in the ICC and had no effects in the ICX. In contrast to observations in the AI, behaviorally relevant ICES had no effects on temporal processing in the ICC or ICX, with the single exception of shorter latencies in the ICC in short-deaf cats. The results suggest that independent of deafness duration passive stimulation and behavioral training differentially transform temporal processing in auditory midbrain and cortex, and primary auditory cortex emerges as a pivotal site for behaviorally driven neuronal temporal plasticity in the deaf cat. Behaviorally relevant vs. passive electric stimulation of the auditory nerve differentially affects neuronal temporal processing in the central nucleus of the inferior colliculus

  15. Construction of multiform scFv antibodies using linker peptide

    Institute of Scientific and Technical Information of China (English)

    Shihua Wang; Cengjie Zheng; Ying Liu; Huirong Zheng; Zonghua Wang

    2008-01-01

    Multiform single chain variable fragments (acFvs) including different length linker scFvs and bispecific seFv were constructed. The linker lengths of 0, 3, 5, 8, 12, and 15 amino acids between VH and VL of antideoxynivalenol (anti-DON) scFv were used to analyze the affinities of scFvs. The affinity constants of these scFvs increased when the linker was lower than 12 amino acids. The affinity constant would not change when the linker was longer than 12 amino acids. Fusion gene of anti-DON seFv and antizearalenone (anti-ZEN) scFv was also constructed through eormection by a short peptide tinker DNA to express a bispecific scFv. The affinity constants assay showed that the two scFvs of fusion bispecific scFv remained their own affinity compared to their parental scFvs. Competitive direct enzyme linked immunosorbent assay was used to detect DON and ZEN in contaminated wheat (Triticum aestivum L.) samples, and the results indicated that this bispecifie acFv was applicable in DON and ZEN detection. This work confirmed that bispecific scFv could be successfully obtained, and might also have an application in diagnosing fungal infection, and breeding transgertic plants.

  16. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity.

    Science.gov (United States)

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S

    2016-04-12

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or "deviance" detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons' overall tuning widths.

  17. Response properties of neurons in the core of the central nucleus of the inferior colliculus of the barn owl.

    Science.gov (United States)

    Wagner, Hermann; Mazer, James A; von Campenhausen, Mark

    2002-04-01

    The central nucleus of the inferior colliculus (ICC) is particularly important for the processing of interaural time differences (ITDs). In the barn owl, neuronal best frequencies in a subnucleus of the ICC, the ICCcore, span the animal's entire hearing range (approximately equal to 200-10 000 Hz). This means that low-frequency ITD-sensitive ICCcore neurons in the owl can be directly compared to ITD-sensitive mammalian ICC neurons with similar best frequencies as well as to the high-frequency ITD-sensitive neurons usually studied in owls. This report represents a first attempt to systematically describe important physiological properties of ICCcore neurons in the barn owl, with particular attention to the low-frequency region (owl's physiological ITD range. ITD tuning widths were inversely correlated with neuronal best frequency. None of the ICCcore neurons studied were sensitive to interaural level differences. Monaural inputs to ICCcore cells were typically binaurally balanced, i.e. they exhibited similar response thresholds, dynamic ranges, slopes and saturation levels, for both left and right ear monaural stimulation.

  18. Dichotic sound localization properties of duration-tuned neurons in the inferior colliculus of the big brown bat.

    Science.gov (United States)

    Sayegh, Riziq; Aubie, Brandon; Faure, Paul A

    2014-01-01

    Electrophysiological studies on duration-tuned neurons (DTNs) from the mammalian auditory midbrain have typically evoked spiking responses from these cells using monaural or free-field acoustic stimulation focused on the contralateral ear, with fewer studies devoted to examining the electrophysiological properties of duration tuning using binaural stimulation. Because the inferior colliculus (IC) receives convergent inputs from lower brainstem auditory nuclei that process sounds from each ear, many midbrain neurons have responses shaped by binaural interactions and are selective to binaural cues important for sound localization. In this study, we used dichotic stimulation to vary interaural level difference (ILD) and interaural time difference (ITD) acoustic cues and explore the binaural interactions and response properties of DTNs and non-DTNs from the IC of the big brown bat (Eptesicus fuscus). Our results reveal that both DTNs and non-DTNs can have responses selective to binaural stimulation, with a majority of IC neurons showing some type of ILD selectivity, fewer cells showing ITD selectivity, and a number of neurons showing both ILD and ITD selectivity. This study provides the first demonstration that the temporally selective responses of DTNs from the vertebrate auditory midbrain can be selective to binaural cues used for sound localization in addition to having spiking responses that are selective for stimulus frequency, amplitude, and duration.

  19. Neural representations of concurrent sounds with overlapping spectra in rat inferior colliculus: Comparisons between temporal-fine structure and envelope.

    Science.gov (United States)

    Luo, Lu; Wang, Qian; Li, Liang

    2017-09-01

    Perceptual segregation of multiple sounds, which overlap in both time and spectra, into individual auditory streams is critical for hearing in natural environments. Some cues such as interaural time disparities (ITDs) play an important role in the segregation, especially when sounds are separated in space. In this study, we investigated the neural representation of two uncorrelated narrowband noises that shared the identical spectrum in the rat inferior colliculus (IC) using frequency-following-response (FFR) recordings, when the ITD for each noise stimulus was manipulated. The results of this study showed that recorded FFRs exhibited two distinctive components: the fast-varying temporal fine structure (TFS) component (FFRTFS) and the slow-varying envelope component (FFRENV). When a single narrowband noise was presented alone, the FFRTFS, but not the FFRENV, was sensitive to ITDs. When two narrowband noises were presented simultaneously, the FFRTFS took advantage of the ITD disparity that was associated with perceived spatial separation between the two concurrent sounds, and displayed a better linear synchronization to the sound with an ipsilateral-leading ITD. However, no effects of ITDs were found on the FFRENV. These results suggest that the FFRTFS and FFRENV represent two distinct types of signal processing in the auditory brainstem and contribute differentially to sound segregation based on spatial cues: the FFRTFS is more critical to spatial release from masking. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Differences in synaptic and intrinsic properties result in topographic heterogeneity of temporal processing of neurons within the inferior colliculus.

    Science.gov (United States)

    Yassin, Lina; Pecka, Michael; Kajopoulos, Jasmin; Gleiss, Helge; Li, Lu; Leibold, Christian; Felmy, Felix

    2016-11-01

    The identification and characterization of organization principals is essential for the understanding of neural function of brain areas. The inferior colliculus (IC) represents a midbrain nexus involved in numerous aspects of auditory processing. Likewise, neurons throughout the IC are tuned to a diverse range of specific stimulus features. Yet beyond a topographic arrangement of the cochlea-inherited frequency tuning, the functional organization of the IC is not well understood. Particularly, a common principle that links the diverse tuning characteristics is unknown. Here we used in vitro patch clamp recordings combined with laser-uncaging, and in vivo single cell recordings to study the spatial and functional organization principles of the central IC. We identified a topographic bias of ascending synaptic input timing that is balanced between inhibition and excitation and co-varies with in vivo first-spike latency. This bias was paralleled post-synaptically by differences in biophysical membrane properties and firing patterns, with integrating neurons predominantly found in the dorso-medial part, and coincidence-detector neurons biased to the ventro-lateral IC. Importantly, these cellular and network features translated into distinct temporal processing capabilities irrespectively of the neurons' characteristic frequency. Our data therefore imply that heterogeneity of synaptic inputs, intrinsic properties and temporal processing are functional principles that underlie the spatial organization of the central IC.

  1. Modulation of cochlear afferent response by the lateral olivocochlear system: activation via electrical stimulation of the inferior colliculus.

    Science.gov (United States)

    Groff, J Alan; Liberman, M Charles

    2003-11-01

    The olivocochlear (OC) efferent innervation of the mammalian inner ear consists of two subdivisions, medial (MOC) and lateral (LOC), with different peripheral terminations on outer hair cells and cochlear afferent terminals, respectively. The cochlear effects of electrically activating MOC efferents are well known, i.e., response suppression effected by reducing outer hair cells' contribution to cochlear amplification. LOC peripheral effects are unknown, because their unmyelinated axons are difficult to electrically stimulate. Here, stimulating electrodes are placed in the inferior colliculus (IC) to indirectly activate the LOC system, while recording cochlear responses bilaterally from anesthetized guinea pigs. Shocks at some IC sites produced novel cochlear effects attributable to activation of the LOC system: long-lasting (5-20 min) enhancement or suppression of cochlear neural responses (compound action potentials and round window noise), without changes in cochlear responses dominated by outer hair cells (otoacoustic emissions and cochlear microphonics). These novel effects also differed from classic MOC effects in their lack of dependence on the level and frequency of the acoustic stimulus. These effects disappeared on sectioning the entire OC bundle, but not after selective lesioning of the MOC tracts or the cochlea's autonomic innervation. We conclude that the LOC pathway comprises two functional subdivisions, capable of inducing slow increases or decreases in response magnitudes in the auditory nerve. Such a system may be useful in maintaining accurate binaural comparisons necessary for sound localization in the face of slow changes in interaural sensitivity.

  2. SC response characteristics of two kinds of coagulant

    Institute of Scientific and Technical Information of China (English)

    杨万东; 宋爽; 史惠祥

    2002-01-01

    Automatic coagulant dosage control with streaming current (SC) technique is introduced in this paper. Aluminum and ferric coagulants are widely used in surface water treatment. The SC response characteristics of P-AlCl3 aluminum coagulant and P-FeCl3 ferric coagulant were investigated in this work. Bench-scale water treatment results were obtained from jar tests including rapid mixing, flocculation and undisturbed sedimentation. Results showed that aluminum coagulant is more sensitive than ferric coagulant to SC response.

  3. SC response characteristics of two kinds of coagulant

    Institute of Scientific and Technical Information of China (English)

    杨万东; 宋爽; 史惠祥

    2002-01-01

    Automatic coagulant dosage control with streaming current (SC) technique is in troduced inthis paper. Aluminum and ferric coagulants are widely used in surface water treatment. The SC response characteristics of P-AiCI3 aluminum coagulant and P-FeCI3 ferric coagulant were investigated in this work. Bench-scale water treatment results were obtained from jar tests including rapid mixing,flocculation and undisturbed sedimentation. Results showed that aluminum coagulant is more sensitive than ferric coagulant to SC response.

  4. Final Scientific Report: DE-SC0002194

    Energy Technology Data Exchange (ETDEWEB)

    Seidler, Gerald [Univ. of Washington, Seattle, WA (United States)

    2017-04-07

    We provide the final scientific report for DE-SC0002194. During the term of this grant, 28 publications spanning a variety of topics were addressed under the rubric of advanced x-ray methods and their application to extreme conditions of time-resolution or x-ray intensities. Notable accomplishments include a new observation of XANES features associated with f-shell reconfiguration in lanthanides, size-dependent x-ray heating effects under XFEL illumination conditions, theoretical development of improved treatments of inelastic x-ray scattering for 'warm dense matter' conditions, and several new instrument develop efforts for atomic, molecular, and condensed phase studies in the lab and at major facility lightsources.

  5. Functional Connectivity Between Superior Parietal Lobule and Primary Visual Cortex "at Rest" Predicts Visual Search Efficiency.

    Science.gov (United States)

    Bueichekú, Elisenda; Ventura-Campos, Noelia; Palomar-García, María-Ángeles; Miró-Padilla, Anna; Parcet, María-Antonia; Ávila, César

    2015-10-01

    Spatiotemporal activity that emerges spontaneously "at rest" has been proposed to reflect individual a priori biases in cognitive processing. This research focused on testing neurocognitive models of visual attention by studying the functional connectivity (FC) of the superior parietal lobule (SPL), given its central role in establishing priority maps during visual search tasks. Twenty-three human participants completed a functional magnetic resonance imaging session that featured a resting-state scan, followed by a visual search task based on the alphanumeric category effect. As expected, the behavioral results showed longer reaction times and more errors for the within-category (i.e., searching a target letter among letters) than the between-category search (i.e., searching a target letter among numbers). The within-category condition was related to greater activation of the superior and inferior parietal lobules, occipital cortex, inferior frontal cortex, dorsal anterior cingulate cortex, and the superior colliculus than the between-category search. The resting-state FC analysis of the SPL revealed a broad network that included connections with the inferotemporal cortex, dorsolateral prefrontal cortex, and dorsal frontal areas like the supplementary motor area and frontal eye field. Noteworthy, the regression analysis revealed that the more efficient participants in the visual search showed stronger FC between the SPL and areas of primary visual cortex (V1) related to the search task. We shed some light on how the SPL establishes a priority map of the environment during visual attention tasks and how FC is a valuable tool for assessing individual differences while performing cognitive tasks.

  6. 75 FR 28542 - Superior Resource Advisory Committee

    Science.gov (United States)

    2010-05-21

    ... orient the new Superior Resource Advisory Committee members on their roles and responsibilities. DATES... of the roles and responsibilities of the Superior Resource Advisory Committee members; Election of... Forest Service Superior Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice...

  7. [The superior laryngeal nerve and the superior laryngeal artery].

    Science.gov (United States)

    Lang, J; Nachbaur, S; Fischer, K; Vogel, E

    1987-01-01

    Length, diameter and anastomoses of the nervus vagus and its ganglion inferius were measured 44 halved heads. On the average, 8.65 fiber bundles of the vagus nerve leave the retro-olivary area. In the area of the jugular foramen is the near superior ganglion of the 10th cranial nerve. In this area were found 1.48 (mean value) anastomoses with the 9th cranial nerve. 11.34 mm below the margo terminalis sigmoidea branches off the ramus internus of the accessory nerve which has a length of 9.75 mm. Further anastomoses with the 10th cranial nerve were found. The inferior ganglion of the 10th nerve had a length of 25.47 mm and a diameter of 3.46 mm. Five mm below the ganglion the 10th nerve had a width of 2.9 and a thickness of 1.5 mm. The mean length of the superior sympathetic ganglion was 26.6 mm, its width 7.2 and its thickness 3.4 mm. In nearly all specimens anastomoses of the superior sympathetic ganglion with the ansa cervicalis profunda and the inferior ganglion of the 10th cranial nerve were found. The superior laryngeal nerve branches off about 36 mm below the margo terminalis sigmoidea. The width of this nerve was 1.9 mm, its thickness 0.8 mm on the right and 1.0 mm on the left side. The division in the internal and external rami was found about 21 mm below its origin. Between the n. vagus and thyreohyoid membrane the ramus internus had a length of 64 mm, the length of external ramus between the vagal nerve and the inferior pharyngeal constrictor muscle was 89 mm. Its mean length below the thyreopharyngeal part was 10.7 mm, 8.6 branchlets to the cricothyroid muscle were counted. The superior laryngeal artery had its origin in 80% of cases in the superior thyroideal artery, in 6.8% this vessel was a branch of the external carotid artery. Its average outer diameter was 1.23 mm on the right side and 1.39 mm on the left. The length of this vessel between its origin and the thyreohyoid membrane was 34 mm. In 7% on the right side and in 13% on the left, the superior

  8. Anomalous Halo Formation in an Arc-Melted ScNi-Sc2Ni Off-Eutectic Binary Alloy

    Directory of Open Access Journals (Sweden)

    Kai Wang

    2016-07-01

    Full Text Available Diverse non-equilibrium eutectic structures have attracted numerous experimental and theoretical studies. One special type is the formation of a halo of one phase around a primary dendrite of another phase. In our experiments, it was occasionally observed that ScNi halos grow as dendritic morphology around the primary Sc 2 Ni dendrites in an arc-melted ScNi-Sc 2 Ni off-eutectic binary alloy. The formation of this anomalous halo structure was then well reproduced by employing quantitative phase-field simulations. Based on the phase-field simulation, It was found that (i the large undercooling and growth velocity of the ScNi phase during solidification causes the formation of halos; and (ii the released latent heat induces the recalescence phenomenon, and changes the solidification sequence largely, resulting in the anomalous halo structure in the Sc-34 at % Ni alloy.

  9. IEC SC15E: Report on liaison activities of CIGRÉ-SC15

    DEFF Research Database (Denmark)

    Henriksen, Mogens

    2000-01-01

    WG’s activities under CIGRÉ SC15:WG 15.01 - Fluid impregnated systems.WG 15.02 - Dielectric Liquids.WG 15.03 - Gas Insulation.WG 15.04 - Outdoor Insulation.WG 15.05 - Capacitors.WG 15.07 - Solid Insulating Materials for Rotating Machines.WG 15/33.08 - Insulation Monitoring and Life Estimation. WG...

  10. Energy dependence of deformation parameters in the SC(p,p') SC reaction

    Energy Technology Data Exchange (ETDEWEB)

    Jones, K.W.; Glashausser, C.; de Swiniarski, R.; Nanda, S.; Carey, T.A.; Cornelius, W.; Moss, J.M.; McClelland, J.B.; Comfort, J.R.; Escudie, J.

    1986-01-01

    Values of deformation parameters have been extracted from macroscopic coupled-channels analyses of inelastic proton scattering to the first 2 , 3 , and 4 states of SC over the energy range from 200 to 700 MeV. The apparent deformations are almost unchanged over this energy interval; they agree also with nucleon scattering data at much lower energies and at 800 MeV and 1 GeV.

  11. What are Millian Qualitative Superiorities?

    Directory of Open Access Journals (Sweden)

    Jonathan Riley

    2008-04-01

    Full Text Available In an article published in Prolegomena 2006, Christoph Schmidt-Petri has defended his interpretation and attacked mine of Mill’s idea that higher kinds of pleasure are superior in quality to lower kinds, regardless of quantity. Millian qualitative superiorities as I understand them are infinite superiorities. In this paper, I clarify my interpretation and show how Schmidt-Petri has misrepresented it and ignored the obvious textual support for it. As a result, he fails to understand how genuine Millian qualitative superiorities determine the novel structure of Mill’s pluralistic utilitarianism, in which a social code of justice that distributes equal rights and duties takes absolute priority over competing considerations. Schmidt-Petri’s own interpretation is a non-starter, because it does noteven recognize that Mill is talking about different kinds of pleasant feelings, such that the higher kinds are intrinsically more valuable than the lower. I conclude by outlining why my interpretation is free of any metaphysical commitment to the “essence” of pleasure.

  12. Isolated superior mesenteric artery dissection

    Directory of Open Access Journals (Sweden)

    Lalitha Palle

    2010-01-01

    Full Text Available Isolated superior mesenteric artery (SMA dissection without involvement of the aorta and the SMA origin is unusual. We present a case of an elderly gentleman who had chronic abdominal pain, worse after meals. CT angiography, performed on a 64-slice CT scanner, revealed SMA dissection with a thrombus. A large artery of Drummond was also seen. The patient was managed conservatively.

  13. Superior cerebellar artery infarction in endovascular treatment for tentorial dural arteriovenous fistulas

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jingbo; Lv Xianli; Jiang Chuhan; Li Youxiang [Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, 6, Tiantan, Xili, Chongwen, 100050, Beijing (China); Wu Zhongxue, E-mail: ttyyzjb@sina.co [Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, 6, Tiantan, Xili, Chongwen, 100050, Beijing (China)

    2010-06-15

    Background: Superior cerebellar artery (SCA) syndrome shows ipsilateral cerebellar ataxia and Horner's syndrome, contralateral superficial sensory disturbance, as well as nystagmus toward the impaired side, vertigo, and nausea. Occasionally, unilateral lesions may produce bilateral hypogeusia and contralateral hypoacusia. Objective: To report 2 patients with unilateral lower midbrain ischemic lesions of the inferior colliculus level caused by transarterial embolization for tentorial dural arteriovenous fistulas (TDAVFs). Methods: Hospital records for 21 patients with TDAVFs mainly treated by endovascular techniques between 2005 and 2008 were reviewed. Two patients with MRI evidence of unilateral SCA territory infarction were investigated. Results: Of 21 patients, 2 treated transarterially with Onyx-18 (a nonahesive liquid embolic agent) developed infarctions in the territory of SCA. One patient had lateral SCA infarction characterized by ipsilateral gait ataxia, contralateral hemihypoesthesia, with additional ipsilateral ocular motor palsy and bilateral gustatory loss. And the other patient had medial SCA infarction characterized by ipsilateral ataxia contralateral hemihypoesthesia with additional contralateral hypoacusia. Conclusion: SCA infarction can be caused by transarterial injection of Onyx-18 via SCA or the posterior cerebral artery (PCA) for TDAVFs and additionally presented with gustatory loss and deafness, which is generally not a feature of the SCA syndrome.

  14. A escrita no Ensino Superior

    Directory of Open Access Journals (Sweden)

    Maria Conceição Pillon Christofoli

    2013-01-01

    Full Text Available http://dx.doi.org/10.5902/198464445865 O presente artigo trata de apresentar resultados oriundos de pesquisa realizada no Ensino Superior, enfocando a escrita em contextos universitários. Depoimentos por parte dos acadêmicos evidenciam certa resistência ao ato de escrever, o que acaba muitas vezes distanciando o sujeito da produção de um texto. Assim sendo, mesmo que parciais, os resultados até então analisados dão conta de que: pressuposto 1 – há ruptura da ideia de coerência entre o que pensamos, o que conseguimos escrever, o que entende nosso interlocutor; pressuposto 2 – a autocorreção de textos como exercício de pesquisa é imprescindível para a qualificação da escrita; pressuposto 3 – os diários de aula representam rico instrumento para a qualificação da escrita no Ensino Superior; pressuposto 4 – há necessidade de que o aluno do Ensino Superior escreva variados tipos de escrita, ainda que a universidade cumpra com seu papel, enfatizando a escrita acadêmica; pressuposto 5 – o trabalho com a escrita no Ensino Superior deve enfatizar os componentes básicos da expressão escrita: o código escrito e a composição da escrita. Palavras-chave: Escrita; Ensino Superior; formação de professores.

  15. Human bulbar conjunctival hemodynamics in hemoglobin SS and SC disease.

    Science.gov (United States)

    Wanek, Justin; Gaynes, Bruce; Lim, Jennifer I; Molokie, Robert; Shahidi, Mahnaz

    2013-08-01

    The known biophysical variations of hemoglobin (Hb) S and Hb C may result in hemodynamic differences between subjects with SS and SC disease. The purpose of this study was to measure and compare conjunctival hemodynamics between subjects with Hb SS and SC hemoglobinopathies. Image sequences of the conjunctival microcirculation were acquired in 9 healthy control subjects (Hb AA), 24 subjects with SC disease, and 18 subjects with SS disease, using a prototype imaging system. Diameter (D) and blood velocity (V) measurements were obtained in multiple venules of each subject. Data were categorized according to venule caliber by averaging V and D for venules with diameters less than (vessel size 1) or greater than (vessel size 2) 15 µm. V in vessel size 2 was significantly greater than V in vessel size 1 in the AA and SS groups (P ≥ 0.009), but not in the SC group (P = 0.1). V was significantly lower in the SC group as compared to the SS group (P = 0.03). In AA and SS groups, V correlated with D (P ≤ 0.005), but the correlation was not statistically significant in the SC group (P = 0.08). V was inversely correlated with hematocrit in the SS group for large vessels (P = 0.03); however, no significant correlation was found in the SC group (P ≥ 0.2). Quantitative assessment of conjunctival microvascular hemodynamics in SS and SC disease may advance understanding of sickle cell disease pathophysiology and thereby improve therapeutic interventions.

  16. 76 FR 58401 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2011-09-21

    ... Zone; Swim Around Charleston, Charleston, SC in the Federal Register (76 FR 38586). We received no... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... temporary moving safety zone during the Swim Around Charleston, a swimming race occurring on waters of...

  17. Thermal stability of Al-Mg-Sc-Zr alloy

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei-tao; YAN De-sheng; RONG Li-jian

    2006-01-01

    The thermal stability of Al3(Sc,Zr) precipitates in the cold worked Al-Mg-Sc-Zr alloy after elevated temperature exposure was investigated. The evaluation was conducted using room temperature tensile, Vicker's hardness, optical metallography and scanning electron microscope (SEM) with the backscatter. The results show that the Al3(Sc,Zr) precipitates and mechanical properties have no obvious change, and the grains keep elongated along the working direction as that in cold worked sample after exposure at 300 ℃ for 1 000 h. The coarsening of Al3(Sc,Zr) precipitates occurs and is no longer effective on the recrystallization resistance, and partial recrystallization is observed after 400 ℃ exposure. In particular, after 500 ℃ exposure, the hardness decreases drastically and the alloy has fully recrystallized due to the obvious coarsening of Al3(Sc,Zr) precipitates.

  18. Cyclotron production of (44)Sc: From bench to bedside.

    Science.gov (United States)

    van der Meulen, Nicholas P; Bunka, Maruta; Domnanich, Katharina A; Müller, Cristina; Haller, Stephanie; Vermeulen, Christiaan; Türler, Andreas; Schibli, Roger

    2015-09-01

    (44)Sc, a PET radionuclide, has promising decay characteristics (T1/2 = 3.97 h, Eβ(+)av = 632 keV) for nuclear imaging and is an attractive alternative to the short-lived (68)Ga (T1/2 = 68 min, Eβ(+)av = 830 keV). The aim of this study was the optimization of the (44)Sc production process at an accelerator, allowing its use for preclinical and clinical PET imaging. (44)CaCO3 targets were prepared and irradiated with protons (~11 MeV) at a beam current of 50 μA for 90 min. (44)Sc was separated from its target material using DGA extraction resin and concentrated using SCX cation exchange resin. Radiolabeling experiments at activities up to 500 MBq and stability tests were performed with DOTANOC by investigating different scavengers, including gentisic acid. Dynamic PET of an AR42J tumor-bearing mouse was performed after injection of (44)Sc-DOTANOC. The optimized chemical separation method yielded up to 2 GBq (44)Sc of high radionuclidic purity. In the presence of gentisic acid, radiolabeling of (44)Sc with DOTANOC was achieved with a radiochemical yield of ~99% at high specific activity (10 MBq/nmol) and quantities which would allow clinical application. The dynamic PET images visualized increasing uptake of (44)Sc-DOTANOC into AR42J tumors and excretion of radioactivity through the kidneys of the investigated mouse. The concept "from-bench-to-bedside" was clearly demonstrated in this extended study using cyclotron-produced (44)Sc. Sufficiently high activities of (44)Sc of excellent radionuclidic purity are obtainable for clinical application, by irradiation of enriched calcium at a cyclotron. This work demonstrates a promising basis for introducing (44)Sc to clinical routine of nuclear imaging using PET. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. The selective neurotoxin DSP-4 impairs the noradrenergic projections from the locus coeruleus to the inferior colliculus in rats.

    Directory of Open Access Journals (Sweden)

    Sebastián eHormigo

    2012-06-01

    Full Text Available The inferior colliculus (IC and the locus coeruleus (LC are two midbrain nuclei that integrate multimodal information and play a major role in novelty detection to elicit an orienting response. Despite the reciprocal connections between these two structures, the projection pattern and target areas of the LC within the subdivisions of the rat IC are still unknown. Here, we used tract-tracing approaches combined with immunohistochemistry, densitometry and confocal microscopy analysis to describe a projection from the LC to the IC. Biotinylated dextran amine (BDA injections into the LC showed that the LC-IC projection is mainly ipsilateral (90% and reaches, to a major extent, the dorsal and lateral part of the IC and the intercollicular commissure. Additionally, some LC fibers extend into the central nucleus of the IC. The neurochemical nature of this projection is noradrenergic, given that tyrosine hydroxylase (TH and dopamine beta hydroxylase (DBH colocalize with the BDA-labeled fibers from the LC. To determine the total field of the LC innervations in the IC, we destroyed the LC neurons and fibers using a highly selective neurotoxin, DSP-4, and then studied the distribution and density of TH- and DBH-immunolabeled axons in the IC. In the DSP-4 treated animals, the number of axonal fibers immunolabeled for TH and DBH were deeply decreased throughout the entire rostrocaudal extent of the IC and its subdivisions compared to controls. Our densitometry results showed that the IC receives up to 97% of its noradrenergic innervations from the LC neurons and only 3% from non-coeruleus neurons. Our results also indicate that TH immunoreactivity in the IC was less impaired than the immunoreactivity for DBH after DSP-4 administration. This is consistent with the existence of an important dopaminergic projection from the substantia nigra to the IC. In conclusion, our study demonstrates and quantifies the noradrenergic projection from the LC to the IC and its

  20. Modulation of major voltage- and ligand-gated ion channels in cultured neurons of the rat inferior colliculus by lidocaine

    Institute of Scientific and Technical Information of China (English)

    Mu YU; Lin CHEN

    2008-01-01

    Aim: The purpose of the present study was to explore how lidocaine as a thera-peutic drug for tinnitus targets voltage- and ligand-gated ion channels and changes the excitability of central auditory neurons. Methods: Membrane cur-rents mediated by major voltage- and ligand-gated channels were recorded from primary cultured neurons of the inferior colliculus (IC) in rats with whole-cell patch-clamp techniques in the presence and absence of lidocaine. The effects of lidocaine on the current-evoked firing of action potentials were also exam-ined. Results: Lidocaine at 100 μmol/L significantly suppressed voltage-gated sodium currents, transient outward potassium currents, and the glycine-induced chloride currents to 87.66%±2.12%, 96.33%±0.35%, and 91.46%±2.69% of that of the control level, respectively. At 1 mmol/L, lidocaine further suppressed the 3 currents to 70.26%±4.69%, 62.80% ±2.61%, and 89.11%±3.17% of that of the control level, respectively, However, lidocaine at concentrations lower than 1 mmol/L did not significantly affect GABA- or aspartate-induced currents. At a higher concentration (3 retool/L), lidocaine slightly depressed the GABA-in-duced current to 87.70%±1.87% of that of the control level. Finally, lidocaine at 100 μmol/L was shown to significantly suppress the current-evoked firing of IC neurons to 58.62%±11.22% of that of the control level, indicating that lidocaine decreases neuronal excitability. Conclusion: Although the action of lidocaine on the ion channels and receptors is complex and non-specific, it has an overall inhibitory effect on IC neurons at a clinically-relevant concentration, suggesting a central mechanism for lidocaine to suppress tinnitus.

  1. The effect of correlated neuronal firing and neuronal heterogeneity on population coding accuracy in guinea pig inferior colliculus.

    Directory of Open Access Journals (Sweden)

    Oran Zohar

    Full Text Available It has been suggested that the considerable noise in single-cell responses to a stimulus can be overcome by pooling information from a large population. Theoretical studies indicated that correlations in trial-to-trial fluctuations in the responses of different neurons may limit the improvement due to pooling. Subsequent theoretical studies have suggested that inherent neuronal diversity, i.e., the heterogeneity of tuning curves and other response properties of neurons preferentially tuned to the same stimulus, can provide a means to overcome this limit. Here we study the effect of spike-count correlations and the inherent neuronal heterogeneity on the ability to extract information from large neural populations. We use electrophysiological data from the guinea pig Inferior-Colliculus to capture inherent neuronal heterogeneity and single cell statistics, and introduce response correlations artificially. To this end, we generate pseudo-population responses, based on single-cell recording of neurons responding to auditory stimuli with varying binaural correlations. Typically, when pseudo-populations are generated from single cell data, the responses within the population are statistically independent. As a result, the information content of the population will increase indefinitely with its size. In contrast, here we apply a simple algorithm that enables us to generate pseudo-population responses with variable spike-count correlations. This enables us to study the effect of neuronal correlations on the accuracy of conventional rate codes. We show that in a homogenous population, in the presence of even low-level correlations, information content is bounded. In contrast, utilizing a simple linear readout, that takes into account the natural heterogeneity, even of neurons preferentially tuned to the same stimulus, within the neural population, one can overcome the correlated noise and obtain a readout whose accuracy grows linearly with the size of

  2. Glutamate receptor antagonism in inferior colliculus attenuates elevated startle response of high anxiety diazepam-withdrawn rats.

    Science.gov (United States)

    Cabral, A; De Ross, J; Castilho, V M; Brandão, M L; Nobre, M J

    2009-07-07

    Rats segregated according to low (LA) or high (HA) anxiety levels have been used as an important tool in the study of fear and anxiety. Since the efficacy of an anxiolytic compound is a function of the animal's basal anxiety level, it is possible that chronic treatment with a benzodiazepine (Bzp) affects LA and HA animals differently. Based on these assumptions, this study aimed to provide some additional information on the influence of acute, chronic (18 days) and withdrawal effects (48 h) from diazepam (10 mg/kg), in rats with LA or HA levels, on startle response amplitude. For this purpose, the elevated plus-maze (EPM) test was used. In addition, the role of glutamate receptors of the central nucleus of the inferior colliculus (cIC), the most important mesencephalic tectum integrative structure of the auditory pathways and a brain region that is linked to the processing of auditory information of aversive nature, was also evaluated. Our results showed that, contrary to the results obtained in LA rats, long-term treatment with diazepam promoted anxiolytic and aversive effects in HA animals that were tested under chronic effects or withdrawal from this drug, respectively. In addition, since Bzp withdrawal may function as an unconditioned stressor, the negative affective states observed in HA rats could be a by-product of GABA-glutamate imbalance in brain systems that modulate unconditioned fear and anxiety behaviors, since the blockade of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and N-methyl-D-aspartate (NMDA) glutamate receptors in the cIC clearly reduced the aversion promoted by diazepam withdrawal.

  3. Effects of microinjections of apomorphine and haloperidol into the inferior colliculus on the latent inhibition of the conditioned emotional response.

    Science.gov (United States)

    Melo, Liana L; Pereira, Ellen C H M; Pagini, Cássia H; Coimbra, Norberto C; Brandão, Marcus L; Ferrari, Elenice A M

    2009-03-01

    Electrical or chemical stimulation of the inferior colliculus (IC) induces fear-like behaviors. More recently, consistent evidence has shown that electrical stimulation of the central nucleus of the IC supports Pavlovian conditioning and latent inhibition (LI). LI is characterized by retardation in conditioning and also by an impaired ability to ignore irrelevant stimuli, after a non-reinforced pre-exposure to the conditioned stimulus. LI has been proposed as a behavioral model of cognitive abnormalities seen in schizophrenia. The aim of the present study was to determine whether dopaminergic mechanisms in the IC are involved in LI of the conditioned emotional response (CER). To induce LI, a group of rats was pre-exposed (PE) to six tones in two sessions, while rats that were not pre-exposed (NPE) had two sessions without tone presentations. The conditioning consisted of two tone presentations to the animal, followed immediately by a foot shock. PE and NPE rats received IC microinjections of physiological saline, the dopaminergic agonist apomorphine (9.0 microg/0.5 microL/side), or the dopaminergic antagonist haloperidol (0.5 microg/0.5 microL/side) before both pre-exposure and conditioning. During the test, the PE rats that received saline or haloperidol had a lower suppression of the licking response compared to NPE rats that received vehicle or haloperidol, indicating that latent inhibition was induced. There was no significant difference in the suppression ratio in rats that received apomorphine injections into the IC, indicating reduced latent inhibition. These results suggest that dopamine-mediated mechanisms of the IC are involved in the development of LI.

  4. Late postnatal shifts of parvalbumin and nitric oxide synthase expression within the GABAergic and glutamatergic phenotypes of inferior colliculus neurons.

    Science.gov (United States)

    Fujimoto, Hisataka; Konno, Kotaro; Watanabe, Masahiko; Jinno, Shozo

    2017-03-01

    The inferior colliculus (IC) is partitioned into three subdivisions: the dorsal and lateral cortices (DC and LC) and the central nucleus (ICC), and serves as an integration center of auditory information. Recent studies indicate that a certain population of IC neurons may represent the non-GABAergic phenotype, while they express well-established cortical/hippocampal GABAergic neuron markers. In this study we used the optical disector to investigate the phenotype of IC neurons expressing parvalbumin (PV) and/or nitric oxide synthase (NOS) in C57BL/6J mice during the late postnatal period. Four major types of IC neurons were defined by the presence (+) or absence (-) of PV, NOS, and glutamic acid decarboxylase 67 (GAD67): PV(+) /NOS(-) /GAD67(+) , PV(+) /NOS(+) /GAD67(+) , PV(+) /NOS(-) /GAD67(-) , and PV(-) /NOS(+) /GAD67(-) . Fluorescent in situ hybridization for vesicular glutamate transporter 2 mRNA indicated that almost all GAD67(-) IC neurons represented the glutamatergic phenotype. The numerical densities (NDs) of total GAD67(+) IC neurons remained unchanged in all subdivisions. The NDs of PV(+) /NOS(-) /GAD67(+) neurons and PV(-) /NOS(+) /GAD67(-) neurons were reduced with age in the ICC, while they remained unchanged in the DC and LC. By contrast, the NDs of PV(+) /NOS(+) /GAD67(+) neurons and PV(+) /NOS(-) /GAD67(-) neurons were increased with age in the ICC, although there were no changes in the DC and LC. The cell body size of GAD67(+) IC neurons did not vary according to the expression of PV with or without NOS. The present findings indicate that the expression of PV and NOS may shift with age within the GABAergic and glutamatergic phenotypes of IC neurons during the late postnatal period. J. Comp. Neurol. 525:868-884, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Hydride vapor phase epitaxy growth of GaN, InGaN, ScN, and ScAIN

    NARCIS (Netherlands)

    Bohnen, T.

    2010-01-01

    Chemical vapor deposition (CVD); hydride vapor phase epitaxy (HVPE); gallium nitride (GaN); indium gallium nitride (InGaN); scandium nitride (ScN); scandium aluminum nitride (ScAlN); semiconductors; thin films; nanowires; III nitrides; crystal growth - We studied the HVPE growth of different III ni

  6. Effective single chain antibody (scFv) concentrations in vivo via adenoviral vector mediated expression of secretory scFv

    NARCIS (Netherlands)

    Arafat, WO; Gomez-Navarro, J; Buchsbaum, DJ; Xiang, J; Casado, E; Barker, SD; Mahasreshti, PJ; Haisma, HJ; Barnes, MN; Siegal, GP; Alvarez, RD; Hemminki, A; Nettelbeck, DM; Curiel, DT

    2002-01-01

    Single chain antibodies (scFv) represent powerful interventional agents for the achievement of targeted therapeutics. The practical utility of these agents have been limited, however, by difficulties related to production of recombinant scFv and the achievement of effective and sustained levels of s

  7. The high-temperature modification of ScRuSi - Structure, 29Si and 45Sc solid state NMR spectroscopy

    Science.gov (United States)

    Hoffmann, Rolf-Dieter; Rodewald, Ute Ch.; Haverkamp, Sandra; Benndorf, Christopher; Eckert, Hellmut; Heying, Birgit; Pöttgen, Rainer

    2017-10-01

    A polycrystalline sample of the TiNiSi type low-temperature (LT) modification of ScRuSi was synthesized by arc-melting. Longer annealing in a sealed silica tube (6 weeks at 1270 K) followed by quenching led to the high-temperature (HT) phase. HT-ScRuSi adopts the ZrNiAl structure type: P 6 bar 2 m , a = 688.27(9), c = 336.72(5) pm, wR2 = 0.0861, 260 F2 values, 14 variables. The striking structural building units are regular, tricapped trigonal prisms Si1@Ru3Sc6 and Si2@Ru6Sc3. Both polymorphs have been characterized by 29Si and 45Sc MAS-NMR spectroscopy. The local scandium environments in the two polymorphs are easily distinguished by their electric field gradient tensor values, in agreement with theoretically calculated values.

  8. Pensamiento Superior y Desarrollo Territorial

    Directory of Open Access Journals (Sweden)

    Víctor Manuel Racancoj Alonzo

    2015-04-01

    Full Text Available Esta reflexión pretende explicar el papel, fundamental, que juega el pensamiento superior, en la formulación y la práctica de modelos de desarrollo territorial local; para que contribuyan de forma sustantiva, en la transformación de las condiciones socioeconómicas adversas que hoy viven comunidades indígenas y rurales de muchos países, como Guatemala, situación que puede resumirse en altos índices de pobreza y desnutrición. Pero, el pensamiento superior, debe ser competencia de la población con pertenencia a lo local, pues si y solo si esta condición existe, se dará validez y viabilidad al desarrollo territorial. Para alcanzar competencias de pensamiento superior, en los espacios locales, se tiene que superar obstáculos en el modelo de universidad, que hoy estamos familiarizados a ver y pensar; modelos que tienen las características de: herencia colonial, disfunción con la problemática económica, cultural, social y política de la sociedad y la negación de los saberes ancestrales.

  9. Superior sulcus tumors (Pancoast tumors).

    Science.gov (United States)

    Marulli, Giuseppe; Battistella, Lucia; Mammana, Marco; Calabrese, Francesca; Rea, Federico

    2016-06-01

    Superior Sulcus Tumors, frequently termed as Pancoast tumors, are a wide range of tumors invading the apical chest wall. Due to its localization in the apex of the lung, with the potential invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, the superior sulcus tumors cause characteristic symptoms, like arm or shoulder pain or Horner's syndrome. The management of superior sulcus tumors has dramatically evolved over the past 50 years. Originally deemed universally fatal, in 1956, Shaw and Paulson introduced a new treatment paradigm with combined radiotherapy and surgery ensuring 5-year survival of approximately 30%. During the 1990s, following the need to improve systemic as well as local control, a trimodality approach including induction concurrent chemoradiotherapy followed by surgical resection was introduced, reaching 5-year survival rates up to 44% and becoming the standard of care. Many efforts have been persecuted, also, to obtain higher complete resection rates using appropriate surgical approaches and involving multidisciplinary team including spine surgeon or vascular surgeon. Other potential treatment options are under consideration like prophylactic cranial irradiation or the addition of other chemotherapy agents or biologic agents to the trimodality approach.

  10. Cyclotron production of {sup 43}Sc for PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Walczak, Rafał [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Krajewski, Seweryn [Synektik S.A., Research and Development Center, Warsaw (Poland); Szkliniarz, Katarzyna [Department of Nuclear Physics, University of Silesia, Katowice (Poland); Sitarz, Mateusz [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Abbas, Kamel [Nuclear Security Unit, Joint Research Centre, Institute for Transuranium Elements, European Commission, Ispra (Italy); Choiński, Jarosław; Jakubowski, Andrzej; Jastrzębski, Jerzy [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Majkowska, Agnieszka [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Simonelli, Federica [Nuclear Decommissioning Unit, Joint Research Centre, Ispra Site Management Directorate, European Commission, Ispra (Italy); Stolarz, Anna; Trzcińska, Agnieszka [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Zipper, Wiktor [Department of Nuclear Physics, University of Silesia, Katowice (Poland); Bilewicz, Aleksander [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

    2015-12-04

    Recently, significant interest in {sup 44}Sc as a tracer for positron emission tomography (PET) imaging has been observed. Unfortunately, the co-emission by {sup 44}Sc of high-energy γ rays (E{sub γ} = 1157, 1499 keV) causes a dangerous increase of the radiation dose to the patients and clinical staff. However, it is possible to produce another radionuclide of scandium—{sup 43}Sc—having properties similar to {sup 44}Sc but is characterized by much lower energy of the concurrent gamma emissions. This work presents the production route of {sup 43}Sc by α irradiation of natural calcium, its separation and purification processes, and the labeling of [DOTA,Tyr3] octreotate (DOTATATE) bioconjugate. Natural CaCO{sub 3} and enriched [{sup 40}Ca]CaCO{sub 3} were irradiated with alpha particles for 1 h in an energy range of 14.8–30 MeV at a beam current of 0.5 or 0.25 μA. In order to find the optimum method for the separation of {sup 43}Sc from irradiated calcium targets, three processes previously developed for {sup 44}Sc were tested. Radiolabeling experiments were performed with DOTATATE radiobioconjugate, and the stability of the obtained {sup 43}Sc-DOTATATE was tested in human serum. Studies of {sup nat}CaCO{sub 3} target irradiation by alpha particles show that the optimum alpha particle energies are in the range of 24–27 MeV, giving 102 MBq/μA/h of {sup 43}Sc radioactivity which creates the opportunity to produce several GBq of {sup 43}Sc. The separation experiments performed indicate that, as with {sup 44}Sc, due to the simplicity of the operations and because of the chemical purity of the {sup 43}Sc obtained, the best separation process is when UTEVA resin is used. The DOTATATE conjugate was labeled by the obtained {sup 43}Sc with a yield >98 % at elevated temperature. Tens of GBq activities of {sup 43}Sc of high radionuclidic purity can be obtainable for clinical applications by irradiation of natural calcium with an alpha beam.

  11. Effects of cooling rate on solidification behavior of dilute Al-Sc and Al-Sc-Zr solid solution

    Institute of Scientific and Technical Information of China (English)

    金头男; 聂祚仁; 徐国富; 阮海琼; 杨军军; 付静波; 左铁镛

    2004-01-01

    Six alloys with different compositions of Al-0.1%Sc, Al-0.3%Sc, Al-0.3%Zr, Al-0.1% Sc-0. 1%Zr,Al-0.3%Sc-0.1%Zr and Al-0.3%Sc-0.3%Zr were prepared by casting in a wedge shaped copper mould. The hardness test, microstructure observation, and DSC thermal analysis were applied to fully investigate the solidification behavior of the wedge tip (whose cooling rate is 1 000 K/s) and the top surface (cooling rate 100 K/s) of each casting. The results show that the cast structures in the hypoeutectic region of Al-Sc alloys are slightly affected by cooling rates during the solidification. In the case of hypereutectic alloy of Al-0.3%Sc-0.3%Zr , the cast grains were remarkably refined under the condition of a 100 K/s cooling rate, however, under a 1 000 K/s cooling rate condition,solute atoms contribute nothing to the grain-refinement, due to the eutectic concentration becomes higher. The hardness can be improved to a greater degree by Sc single addition, compared to single Zr addition, but it can be improved even greater when Sc added together with Zr. It is sensitive to cooling rate, the higher the cooling rate, the greater the hardness. By combining the results of TEM examination and DSC analysis, it can be seen that a supersaturated Al solid solution forms during the solidification, and the solubility of Sc in Al solution can be improved by increasing the cooling rate.

  12. The influence of shear-velocity heterogeneity on ScS2/ScS amplitude ratios and estimates of Q in the mantle

    Science.gov (United States)

    Chaves, Carlos A. M.; Ritsema, Jeroen

    2016-08-01

    Regional waveforms of deep-focus Tonga-Fiji earthquakes indicate anomalous traveltime differences (ScS2-ScS) and amplitude ratios (ScS2/ScS) of the phases ScS and ScS2. The correlation between the ScS2-ScS delay time and the ScS2/ScS amplitude ratio suggests that shear wave apparent Q in the mantle below the Tonga-Fiji region is highest when shear wave velocities are lowest. This observation is unexpected if temperature variations were responsible for the seismic anomalies. Using spectral element method waveform simulations for four tomographic models, we demonstrate that focusing and scattering of shear waves by long-wavelength 3-D heterogeneity in the mantle may overwhelm the signal from intrinsic attenuation in long-period ScS2/ScS amplitude ratios. The tomographic models reproduce the trends in recorded ScS2-ScS difference times and ScS2/ScS amplitude ratios. Although they cannot be ruled out, variations in shear wave attenuation (i.e., the quality factor Q) are not necessary to explain the data.

  13. Pascal-SC a computer language for scientific computation

    CERN Document Server

    Bohlender, Gerd; von Gudenberg, Jürgen Wolff; Rheinboldt, Werner; Siewiorek, Daniel

    1987-01-01

    Perspectives in Computing, Vol. 17: Pascal-SC: A Computer Language for Scientific Computation focuses on the application of Pascal-SC, a programming language developed as an extension of standard Pascal, in scientific computation. The publication first elaborates on the introduction to Pascal-SC, a review of standard Pascal, and real floating-point arithmetic. Discussions focus on optimal scalar product, standard functions, real expressions, program structure, simple extensions, real floating-point arithmetic, vector and matrix arithmetic, and dynamic arrays. The text then examines functions a

  14. III-V compound SC for optoelectronic devices

    Directory of Open Access Journals (Sweden)

    Sudha Mokkapati

    2009-04-01

    Full Text Available III-V compound semiconductors (SC have played a crucial role in the development of optoelectronic devices for a broad range of applications. Major applications of InP or GaAs based III-V compound SC are devices for optical fiber communications, infrared and visible LEDs/LDs and high efficiency solar cells. GaN based compounds are extremely important for short wavelength light emitters used in solid state lighting systems. We review the important device applications of various III-V compound SC materials.

  15. SC-System of convergence theory and foundations

    Directory of Open Access Journals (Sweden)

    Sergio G. De los Cobos Silva

    2015-08-01

    Full Text Available In this paper a novel system of convergence (SC is presented as well as its fundamentals and computing experience. An implementation using a novel mono-objetive particle swarm optimization (PSO algorithm with three phases (PSO-3P: stabilization, generation with broad-ranging exploration and generation with in-depth exploration, is presented and tested in a diverse benchmark problems. Evidence shows that the three-phase PSO algoritm along with the SC criterion (SC-PSO-3Pcan converge to the global optimum in several difficult test functions for multiobjective optimization problems, constrained optimization problems and unconstrained optimization problems with 2 until 120,000 variables.

  16. Gadolinium scandium germanide, Gd2Sc3Ge4

    Directory of Open Access Journals (Sweden)

    Sumohan Misra

    2009-04-01

    Full Text Available Gd2Sc3Ge4 adopts the orthorhombic Pu5Rh4-type structure. The crystal structure contains six sites in the asymmetric unit: two sites are statistically occupied by rare-earth atoms with Gd:Sc ratios of 0.967 (4:0.033 (4 and 0.031 (3:0.969 (3, one site (.m. symmetry is occupied by Sc atoms, and three distinct sites (two of which with .m. symmetry are occupied by Ge atoms. The rare-earth atoms form two-dimensional slabs with Ge atoms occupying the trigonal-prismatic voids.

  17. Aminoglycosides block the Kv3.1 potassium channel and reduce the ability of inferior colliculus neurons to fire at high frequencies.

    Science.gov (United States)

    Liu, Si-Qiong J; Kaczmarek, Leonard K

    2005-03-01

    The Kv3.1 potassium channel is expressed at high levels in auditory nuclei and contributes to the ability of auditory neurons to fire at high frequencies. We have tested the effects of streptomycin, an agent that produces progressive hearing loss, on the firing properties of inferior colliculus neurons and on Kv3.1 currents in transfected cells. We found that in inferior colliculus neurons, intracellular streptomycin decreased the current density of a high threshold, noninactivating outward current and reduced the rate of repolarization of action potentials and the ability of these neurons to fire at high frequencies. Furthermore, potassium current in CHO cells transfected with the Kv3.1 gene was reduced by 50% when cells were cultured in the presence of streptomycin or when streptomycin was introduced intracellularly in the pipette solution. In the presence of intracellular streptomycin, the activation rate of Kv3.1 current increased and inhibition by extracellular TEA become voltage-dependent. The data indicate that streptomycin inhibits Kv3.1 currents by inducing a conformational change in the Kv3.1 channel. The hearing loss caused by aminoglycoside antibiotics may be partially mediated by their inhibition of Kv3.1 current in auditory neurons.

  18. Infectivity-associated PrP(Sc) and disease duration-associated PrP(Sc) of mouse BSE prions.

    Science.gov (United States)

    Miyazawa, Kohtaro; Okada, Hiroyuki; Masujin, Kentaro; Iwamaru, Yoshifumi; Yokoyama, Takashi

    2015-01-01

    Disease-related prion protein (PrP(Sc)), which is a structural isoform of the host-encoded cellular prion protein, is thought to be a causative agent of transmissible spongiform encephalopathies. However, the specific role of PrP(Sc) in prion pathogenesis and its relationship to infectivity remain controversial. A time-course study of prion-affected mice was conducted, which showed that the prion infectivity was not simply proportional to the amount of PrP(Sc) in the brain. Centrifugation (20,000 ×g) of the brain homogenate showed that most of the PrP(Sc) was precipitated into the pellet, and the supernatant contained only a slight amount of PrP(Sc). Interestingly, mice inoculated with the obtained supernatant showed incubation periods that were approximately 15 d longer than those of mice inoculated with the crude homogenate even though both inocula contained almost the same infectivity. Our results suggest that a small population of fine PrP(Sc) may be responsible for prion infectivity and that large, aggregated PrP(Sc) may contribute to determining prion disease duration.

  19. Entidades fiscalizadoras superiores y accountability

    OpenAIRE

    Estela Moreno, María

    2016-01-01

    OBJETIVOS DE LA TESIS: El objetivo general del trabajo es establecer el nivel de eficacia de las Entidades Fiscalizadoras Superiores (EFS) como agencia asignada y herramienta de accountability horizontal, a través de la valoración de su diseño institucional y de la calidad de sus productos finales, los informes de auditoría, estableciéndose los siguientes objetivos específicos: 1. Relevar las nociones de accountability, actualizando el Estado del Arte de la cuestión. 2. Analizar la ...

  20. Superior activity of fusion protein scFvRit : sFasL over cotreatment with rituximab and Fas agonists

    NARCIS (Netherlands)

    Bremer, Edwin; ten Cate, Bram; Samplonius, Douwe F.; Mueller, Nicole; Wajant, Harald; Stel, Aja J.; Chamuleau, Martine; de Loosdrecht, Arjan A. van; Stieglmaier, Julia; Fey, Georg H.; Helfrich, Wijnand

    2008-01-01

    The clinical efficacy of the CD20-specific chimeric monoclonal antibody rituximab is significantly hampered by intrinsic or acquired resistance to therapy. Rituximab activates antibody-dependent cellular cytotoxicity/complement-dependent cytotoxicity-dependent lysis but also induces apoptosis by cro

  1. Precipitation in cold-rolled Al-Sc-Zr and Al-Mn-Sc-Zr alloys prepared by powder metallurgy

    KAUST Repository

    Vlach, Martin

    2013-12-01

    The effects of cold-rolling on thermal, mechanical and electrical properties, microstructure and recrystallization behaviour of the AlScZr and AlMnScZr alloys prepared by powder metallurgy were studied. The powder was produced by atomising in argon with 1% oxygen and then consolidated by hot extrusion at 350 C. The electrical resistometry and microhardness together with differential scanning calorimetry measurements were compared with microstructure development observed by transmission and scanning electron microscopy, X-ray diffraction and electron backscatter diffraction. Fine (sub)grain structure developed and fine coherent Al3Sc and/or Al3(Sc,Zr) particles precipitated during extrusion at 350 C in the alloys studied. Additional precipitation of the Al3Sc and/or Al3(Sc,Zr) particles and/or their coarsening was slightly facilitated by the previous cold rolling. The presence of Sc,Zr-containing particles has a significant antirecrystallization effect that prevents recrystallization at temperatures minimally up to 420 C. The precipitation of the Al6Mn- and/or Al 6(Mn,Fe) particles of a size ~ 1.0 μm at subgrain boundaries has also an essential antirecrystallization effect and totally suppresses recrystallization during 32 h long annealing at 550 C. The texture development of the alloys seems to be affected by high solid solution strengthening by Mn. The precipitation of the Mn-containing alloy is highly enhanced by a cold rolling. The apparent activation energy of the Al3Sc particles formation and/or coarsening and that of the Al6Mn and/or Al 6(Mn,Fe) particle precipitation in the powder and in the compacted alloys were determined. The cold deformation has no effect on the apparent activation energy values of the Al3Sc-phase and the Al 6Mn-phase precipitation. © 2013 Elsevier Inc.

  2. Design of SC walls and slabs for impulsive loading

    Energy Technology Data Exchange (ETDEWEB)

    Varma, Amit H. [Purdue Univ., West Lafayette, IN (United States)

    2015-11-11

    Reinforced concrete (RC) structures have historically been the preferred choice for blast resistant structures because of their mass and the ductility provided by steel reinforcement. Steel-plate composite (SC) walls are a viable alternative to RC for protecting the infrastructure against explosive threats. SC structures consist of two steel faceplates with a plain concrete core between them. The steel faceplates are anchored to the concrete using stud anchors and connected to each other using tie bars. SC structures provide mass from the concrete infill and ductility from the continuous external steel faceplates. This dissertation presents findings and recommendations from experimental and analytical investigations of the performance of SC walls subjected to far-field blast loads.

  3. The data acquisition system (DAS) for the improved CERN SC

    CERN Document Server

    Beger, H; Fiebig, A; Schroot, H

    1975-01-01

    A digital data acquisition system (DAS) based on a minicomputer is described which registers the failure sequences in various equipment areas of the CERN synchrocyclotron (henceforward referred to as the SC). The avalanches of failure signals which occur from time to time are tapped from the alarm/security systems, time-resolved to 10 msec and recorded on a printer in order to aid SC failure diagnosis. The mechanisms of the DAS and its relation to the SC equipment are explained in some detail. All programs were constructed at assembler language level for speed and for ease of on-line program maintenance. The alarm sequences recorded have been of considerable help during the running in of the new radiofrequency system. Now that the new SC is operational, the DAS furnishes useful data from several equipment areas to the operators and engineers.

  4. 75 FR 71734 - Outer Continental Shelf (OCS), Scientific Committee (SC)

    Science.gov (United States)

    2010-11-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf (OCS), Scientific Committee (SC) AGENCY: Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE),...

  5. Aging of Al-0,3 at. % Sc alloy

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Ber, L.B.; Bykov, L.S.; Toropova, L.S.; Anastas' eva, G.K. (AN SSSR, Moscow. Inst. Metallurgii)

    1984-06-01

    Method of measuring electric conductivity, hardness and yield limit was used to study the kinetics of aging of Al-0.3 at.%Sc alloy in 20-450 deg c range. It was established by X-ray methods of monocrystal investigation and diffraction electron microscopy that coherent precipitations of equilibrium ScAl/sub 3/ pha se with li/sub 2/ type structure and 0.41 nm lattice parameter represent the product of decomposition of supersaturated solid solution. Characteristic features and the kinetics of ScAl/sub 3/ phase particle growth were studied by the electron microscopic method. The activation energy of scandium and aluminium diffusion equal to 3.81 MJ/kg was determined. The analysis of deformation hardening of Al-0.3 at.%Sc alloy at different stages of aging was conducted.

  6. The sentence superiority effect revisited.

    Science.gov (United States)

    Snell, Joshua; Grainger, Jonathan

    2017-11-01

    A sentence superiority effect was investigated using post-cued word-in-sequence identification with the rapid parallel visual presentation (RPVP) of four horizontally aligned words. The four words were presented for 200ms followed by a post-mask and cue for partial report. They could form a grammatically correct sentence or were formed of the same words in a scrambled agrammatical sequence. Word identification was higher in the syntactically correct sequences, and crucially, this sentence superiority effect did not vary as a function of the target's position in the sequence. Cloze probability measures for words at the final, arguably most predictable position, revealed overall low values that did not interact with the effects of sentence context, suggesting that these effects were not driven by word predictability. The results point to a level of parallel processing across multiple words that enables rapid extraction of their syntactic categories. These generate a sentence-level representation that constrains the recognition process for individual words, thus facilitating parallel word processing when the sequence is grammatically sound. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. The selective neurotoxin DSP-4 impairs the noradrenergic projections from the locus coeruleus to the inferior colliculus in rats.

    Science.gov (United States)

    Hormigo, Sebastián; Horta Júnior, José de Anchieta de Castro E; Gómez-Nieto, Ricardo; López, Dolores E

    2012-01-01

    The inferior colliculus (IC) and the locus coeruleus (LC) are two midbrain nuclei that integrate multimodal information and play a major role in novelty detection to elicit an orienting response. Despite the reciprocal connections between these two structures, the projection pattern and target areas of the LC within the subdivisions of the rat IC are still unknown. Here, we used tract-tracing approaches combined with immunohistochemistry, densitometry, and confocal microscopy (CM) analysis to describe a projection from the LC to the IC. Biotinylated dextran amine (BDA) injections into the LC showed that the LC-IC projection is mainly ipsilateral (90%) and reaches, to a major extent, the dorsal and lateral part of the IC and the intercollicular commissure. Additionally, some LC fibers extend into the central nucleus of the IC. The neurochemical nature of this projection is noradrenergic, given that tyrosine hydroxylase (TH) and dopamine beta hydroxylase (DBH) colocalize with the BDA-labeled fibers from the LC. To determine the total field of the LC innervations in the IC, we destroyed the LC neurons and fibers using a highly selective neurotoxin, DSP-4, and then studied the distribution and density of TH- and DBH-immunolabeled axons in the IC. In the DSP-4 treated animals, the number of axonal fibers immunolabeled for TH and DBH were deeply decreased throughout the entire rostrocaudal extent of the IC and its subdivisions compared to controls. Our densitometry results showed that the IC receives up to 97% of its noradrenergic innervations from the LC neurons and only 3% from non-coeruleus neurons. Our results also indicate that TH immunoreactivity in the IC was less impaired than the immunoreactivity for DBH after DSP-4 administration. This is consistent with the existence of an important dopaminergic projection from the substantia nigra to the IC. In conclusion, our study demonstrates and quantifies the noradrenergic projection from the LC to the IC and its

  8. Early monaural occlusion alters the neural map of interaural level differences in the inferior colliculus of the barn owl.

    Science.gov (United States)

    Mogdans, J; Knudsen, E I

    1993-08-13

    Monaural occlusion during early life causes adaptive changes in the tuning of units in the owl's optic tectum to interaural level differences (ILD) that tend to align the auditory with the visual map of space. We investigated whether these changes could be due to experience-dependent plasticity occurring in the auditory pathway prior to the optic tectum. Units were recorded in the external nucleus of the inferior colliculus (ICx), which is a major source of auditory input to the optic tectum. The tuning of ICx units to ILD was measured in normal barn owls and in barn owls raised with one ear occluded. ILD tuning at each recording site was measured with dichotic noise bursts, presented at a constant average binaural level, 20 dB above threshold. The best ILD at each site was defined as the midpoint of the range of ILD values which elicited more than 50% of the maximum response. A physiological map of ILD was found in the ICx of normal owls: best ILDs changed systematically from right-ear-greater to left-ear-greater as the electrode progressed from dorsal to ventral. Best ILDs ranged from 13 dB right-ear-greater to 15 dB left-ear-greater and progressed at an average rate of 12 dB/mm. The representations of ILD were similar on both sides of the brain. In the ICx of owls raised with one ear occluded, the map of ILD was shifted in the adaptive direction: ILD tuning was shifted towards values favoring the non-occluded ear (the direction that would restore a normal space map). The average magnitude of the shift was on the order of 8-10 dB in each of 4 owls. In one owl, the mean shift in ILD tuning was almost identical on both sides of the brain. In another owl, the mean shift was much larger on the side ipsilateral to the occlusion than on the contralateral side. In both cases, the mean shifts measured in each ICx were comparable to the mean shifts measured in the optic tectum on the same sides of the brain. Thus, the adjustments in ILD tuning that have been observed in

  9. Magnetic properties of the Sc-H system

    Energy Technology Data Exchange (ETDEWEB)

    Volkenshtein, N.V.; Galoshina, E.V. (AN SSSR, Sverdlovsk. Ural' skij Nauchnyj Tsentr); Kost, M.E. (AN SSSR, Moscow. Inst. Obshchej i Neorganicheskoj Khimii); Shubina, T.S. (Ural' skij Gosudarstvennyj Univ., Sverdlovsk (USSR))

    1983-05-01

    The magnetic susceptibility in the ..cap alpha..-phase region of the Sc-H system and in scandium hydrides ScH/sub 2/ is investigated. The temperature dependence of the susceptibility was measured from liquid-helium temperature to room temperature in a magnetic field of 10 kOe. The influence of hydrogenation and of band structure parameters (density of states at the Fermi level, spin-relaxation time, and Fermi energy) on the susceptibility is shown and discussed.

  10. Homogenization of alloys in the system Al-Mg-Sc

    Science.gov (United States)

    Drits, M. E.; Toropova, L. S.; Bykov, Yu. G.

    1983-07-01

    A reduction in homogenizing anneal temperature and a reduction in soaking time leads to an increase in yield point for alloys of the system Al-Mg-Sc. The optimum homogenizing schedule for alloys of this system is heating to 400°C and soaking for up to 10 h. This homogenizing schedule provides an alloy structure of fine coherent ScAl3-phase precipitates and dissolution of excess β-phase precipitates.

  11. DE-SC0002437 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Todd E. [Vanderbilt University

    2014-04-21

    We developed a SPECT/CT system for small-animal imaging utilizing a mechanically cooled, position-sensitive germanium detector for the SPECT camera. The detector offers better energy resolution than any other detector previously used for SPECT and demonstrates dual-isotope imaging capabilities superior to that of current commercial small-animal SPECT systems. We also explored a unique SPECT camera configuration consisting of a silicon detector and germanium detector stacked one behind the other and located behind a multi-pinhole collimator. This scheme is intended for imaging iodine-123 radiotracer distributions, with the ~30 keV x-ray emissions detected in the silicon detector and the 159 keV gamma-ray emissions passing through the silicon and detected in the germanium detector. Image reconstruction methods for combining this multi-energy, multi-magnification data were developed and it was shown that inclusion of the silicon data reduced artifacts in comparison to the germanium data alone.

  12. Theoretical studies of the low-lying states of ScO, ScS, VO, and VS

    Science.gov (United States)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.

    1986-01-01

    Bonding in the low-lying states of ScO, ScS, VO, and VS is theoretically studied. Excellent agreement is obtained with experimental spectroscopic constants for the low-lying states of ScO and VO. The results for VS and ScS show that the bonding in the oxides and sulfides is similar, but that the smaller electronegativity in S leads to a smaller ionic component in the bonding. The computed D0 of the sulfides are about 86 percent of the corresponding oxides, and the low-lying excited states are lower in the sulfides than in the corresponding oxides. The CPF method is shown to be an accurate and cost-effective method for obtaining reliable spectroscopic constants for these systems.

  13. Effect of homogenizing heatings on the properties of Al-Sc and Al-Mg-Sc alloy systems

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Toropova, L.S.; Anastas' eva, G.K.; Nagornichnykh, G.L.

    Effect of annealing on hardness and electric conductivity of cast alloys of Al-Mg-Sc and Al-Sc systems has been studied. Magnesium content in studied alloys was changed in the range of 0-6.5%, scandium content was chosen to be constant -0.4%. It has been revealed that homogenizing heatings of Al-Sc alloys lead to a decomposition of abnormally saturated solid solution during crystallization at temperatures >250 deg C. Maximum hardness values are achieved after annealing at 300 deg C during 1h. Homogenizing of Al-Mg--- Sc alloys at 350 deg C during 24h leads to practically full solubility of a nonequilibrium ..beta..-phase (Mg/sub 2/Al/sub 3/) and also to a decomposition of a solid solution abnormally saturated with scandium. Maximum values of hardness are achieved after annealing at 35O deg C during 0.5-1h.

  14. 78 FR 21116 - Superior Supplier Incentive Program

    Science.gov (United States)

    2013-04-09

    ... Department of the Navy Superior Supplier Incentive Program AGENCY: Department of the Navy, DoD. ACTION... policy that will establish a Superior Supplier Incentive Program (SSIP). Under the SSIP, contractors that..., performance, quality, and business relations would be granted Superior Supplier Status (SSS). Contractors...

  15. Compensation of native donor doping in ScN: Carrier concentration control and p-type ScN

    Science.gov (United States)

    Saha, Bivas; Garbrecht, Magnus; Perez-Taborda, Jaime A.; Fawey, Mohammed H.; Koh, Yee Rui; Shakouri, Ali; Martin-Gonzalez, Marisol; Hultman, Lars; Sands, Timothy D.

    2017-06-01

    Scandium nitride (ScN) is an emerging indirect bandgap rocksalt semiconductor that has attracted significant attention in recent years for its potential applications in thermoelectric energy conversion devices, as a semiconducting component in epitaxial metal/semiconductor superlattices and as a substrate material for high quality GaN growth. Due to the presence of oxygen impurities and native defects such as nitrogen vacancies, sputter-deposited ScN thin-films are highly degenerate n-type semiconductors with carrier concentrations in the (1-6) × 1020 cm-3 range. In this letter, we show that magnesium nitride (MgxNy) acts as an efficient hole dopant in ScN and reduces the n-type carrier concentration, turning ScN into a p-type semiconductor at high doping levels. Employing a combination of high-resolution X-ray diffraction, transmission electron microscopy, and room temperature optical and temperature dependent electrical measurements, we demonstrate that p-type Sc1-xMgxN thin-film alloys (a) are substitutional solid solutions without MgxNy precipitation, phase segregation, or secondary phase formation within the studied compositional region, (b) exhibit a maximum hole-concentration of 2.2 × 1020 cm-3 and a hole mobility of 21 cm2/Vs, (c) do not show any defect states inside the direct gap of ScN, thus retaining their basic electronic structure, and (d) exhibit alloy scattering dominating hole conduction at high temperatures. These results demonstrate MgxNy doped p-type ScN and compare well with our previous reports on p-type ScN with manganese nitride (MnxNy) doping.

  16. superior en México

    Directory of Open Access Journals (Sweden)

    César Mureddu Torres

    2008-01-01

    Full Text Available El presente artículo desarrolla algunos de los retos que ha traído consigo el acceso a la información existente en la red de Internet y lo que ello supone. Se abordan principalmente las consecuencias de la presencia actual de una sociedad llamada del conocimiento, si se mantiene la confusión entre conocimiento e información. Por ello, la sola gestión de la información no puede ser tomada como definitoria respecto a la función de educación superior confiada a las universidades. Hacerlo sería cometer un error aún más grave que la confusión teórica entre los términos mencionados.

  17. Subtalar arthrodesis stabilisation with screws in an angulated configuration is superior to the parallel disposition: a biomechanical study.

    Science.gov (United States)

    Eichinger, Martin; Schmölz, Werner; Brunner, Alexander; Mayr, Raul; Bölderl, Andreas

    2015-11-01

    The purpose of this study was to compare the stability of two established screw configurations (SC) for subtalar arthrodesis using a cyclic loading model. Eight paired human cadaver hindfoot specimens underwent subtalar arthrodesis with either parallel or angulated SC. The instrumented specimens were subjected to a cyclic loading protocol (1000 cycles: ±5 Nm rotation moment, 50 N axial force). The joint range of motion (ROM) was quantified before and after cyclic loading, in the three principal motion planes of the subtalar joint using pure bending moments of ±3 Nm. After instrumentation, the angulated SC showed significantly less mean ROM compared to the parallel SC in internal/external rotation (1.4° ± 2.2° vs. 3.3° ± 2.8°, P = 0.006) and in inversion/eversion (0.9° ± 1.4° vs. 1.5° ± 1.1°, P = 0.049). After cyclic loading, the angulated SC resulted in significantly less mean ROM compared to the parallel SC in internal/external rotation (3.3° ± 4.6° vs. 8.8° ± 8.0°, P = 0.006) and in inversion/eversion (1.9° ± 2.3° vs. 3.9° ± 3.9°, P = 0.017). No significant differences in the mean ROM were found between the angulated and parallel SC in dorsal extension/plantar flexion. The angulated SC resulted in decreased ROM in the subtalar arthrodesis construct after instrumentation and after cyclic loading compared to the parallel SC. The data from our study suggest that the clinical use of the angulated SC for subtalar arthrodesis might be superior to the parallel SC.

  18. Final Technical Report for Award SC0008613

    Energy Technology Data Exchange (ETDEWEB)

    Knopf, Daniel A. [Stony Brook Univ., NY (United States)

    2017-04-05

    Discovering how aerosol particles, present in the atmosphere in sizes of a few nanometers to hundred micrometers, initiate ice crystal formation represents a great challenge. Atmospheric ice nucleation is important because ice crystals alter the radiative properties of clouds and thus climate, and impact precipitation and thus the hydrological cycle. The difficulty in predicting atmospheric ice formation is attributable at least in part, to the diversity of ice nucleation pathways, the physical and chemical complexity of the ice nucleating particles (INPs), and the relatively small numbers of INPs (compared with all other aerosol particles), sometimes less than one in 100000. These factors in turn makes constraining ice nucleation parameterizations for modeling applications challenging. The majority of airborne particles are known to be organic in nature or contain organic biogenic material. The presence of organic material adds to the complexity of the particles and therefore the predictability of ice nucleation events since the organic species can display different phase states, e.g. liquid or solid, in response to temperature and humidity. The award DE-SC0008613 to PI Prof. Daniel Knopf at Stony Brook University, “Relating the Chemical and Physical Properties of Aerosols to the Water Uptake and Ice Nucleation Potential of Particles Collected During the Carbonaceous Aerosols and Radiative Effects Study (CARES)”, allowed examination of laboratory generated aerosol particles and field-collected particles for their propensity to nucleate ice under typical tropospheric conditions and relate ice nucleation to the physicochemical properties of the particles including their morphology and chemical composition. This in turn allowed for development of ice nucleation parameterizations for implementation in cloud models. The award resulted in 10 peer-reviewed publications and more than 20 seminar and conference presentations. We demonstrated that the rate of immersion

  19. Medialogy (English Information Brochure on the education M.Sc.,Medialogy, 3rd to 10th semester (B.Sc. & M.Sc) - For graduates from higher study programmes such as Multimedia Design and IT Graduates)

    DEFF Research Database (Denmark)

    Nordahl, Rolf

    2005-01-01

    An information brochure, 24 pages, in English which describes the education M.Sc., Medialogy, offered by Aalborg University in Copenhagen and Esbjerg. The brochure describes the 3rd to 10th semester (B.Sc. and M.Sc. degree) of the education. The information is primarily directed toward potential...

  20. Escuela Superior de Palos Verdes

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1965-02-01

    Full Text Available Before initiating the building operations for the «Palos Verdes» School, the site was divided into two large horizontal surfaces, at different levels. The lower one served to accommodate the playing fields, a car park, the physical training building, and shop and ancillary buildings. On the higher of these two surfaces, and to the West of the access road, there is a car park and also the building and plot of ground devoted to agricultural technology, as well as the literary studies and general purpose buildings. As a complement to these, there is a series of blocks, arranged in parallel rows, which house the administrative offices, the art school, the craft's school, the general classrooms, and those devoted to higher education. The fascinating aspect of this school is the outstanding penetration of the architect's mind into the essential function of the project. Its most evident merit is the sense of comradeship and harmony that permeates the whole architectural manifold.Antes de construir el complejo escolar «Palos Verdes» se comenzó por crear, en el terreno, dos grandes mesetas a niveles diferentes. Sobre el inferior se organizaron: los campos de juegos, de deportes, un aparcamiento, el edificio para educación física y los destinados a tiendas y servicios. Sobre la meseta superior, al oeste de la vía de acceso, se dispuso un aparcamiento y el edificio y campo para adiestramiento agrícola; al este, otro aparcamiento, el edificio dedicado a materias literarias, y el destinado a usos múltiples. Completan las instalaciones de la escuela una serie de bloques paralelos: la administración, la escuela de arte, las clases de trabajos manuales, las aulas de enseñanzas generales, y las de los cursos superiores. Lo fascinante de este complejo escolar es la perfecta y magistral compenetración del arquitecto con el tema proyectado, y su mayor mérito, la sensación de cordialidad y armonía con el ambiente.

  1. Piezoelectric coefficients and spontaneous polarization of ScAlN.

    Science.gov (United States)

    Caro, Miguel A; Zhang, Siyuan; Riekkinen, Tommi; Ylilammi, Markku; Moram, Michelle A; Lopez-Acevedo, Olga; Molarius, Jyrki; Laurila, Tomi

    2015-06-24

    We present a computational study of spontaneous polarization and piezoelectricity in Sc(x)Al(1-x)N alloys in the compositional range from x = 0 to x = 0.5, obtained in the context of density functional theory and the Berry-phase theory of electric polarization using large periodic supercells. We report composition-dependent values of piezoelectric coefficients e(ij), piezoelectric moduli d(ij) and elastic constants C(ij). The theoretical findings are complemented with experimental measurement of e33 for a series of sputtered ScAlN films carried out with a piezoelectric resonator. The rapid increase with Sc content of the piezoelectric response reported in previous studies is confirmed for the available data. A detailed description of the full methodology required to calculate the piezoelectric properties of ScAlN, with application to other complex alloys, is presented. In particular, we find that the large amount of internal strain present in ScAlN and its intricate relation with electric polarization make configurational sampling and the use of large supercells at different compositions necessary in order to accurately derive the piezoelectric response of the material.

  2. Solid state reaction synthesis and photoluminescence properties of Dy{sup 3+} doped Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12} phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Long, Qiang; Wang, Chuang; Li, Yanyan; Ding, Jianyan; Wang, Xicheng; Wang, Yuhua, E-mail: wyh@lzu.edu.cn

    2015-11-15

    Highlights: • Ca{sub 3−x}Sc{sub 2}Si{sub 3}O{sub 12}:xDy{sup 3+} (0.01 ≤ x ≤ 0.03) was successfully synthesized under a reducing atmosphere. • The thermal stability of the Ca{sub 2.975}Sc{sub 2}Si{sub 3}O{sub 12}:0.025Dy{sup 3+} is superior to commercial phosphors in theory and experiment. • The optimal chromaticity coordinates of Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Dy{sup 3+} is (x = 0.3425, y = 0.3343) upon 350 nm excitation. - Abstract: The white emission phosphor Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Dy{sup 3+} was synthesized by the solid-state reaction. Phase analysis and characteristic luminescence properties are investigated by X-ray diffraction and photoluminescence spectra measurement. Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Dy{sup 3+} phosphor shows strong absorption in 350–410 nm region and exhibits white emission with CIE chromaticity coordinates of (0.3425, 0.3343). Its emission intensity at 250 °C remained 74% of that measured at room temperature. Moreover, the activation energy is also calculated through the Arrhenius equation. The result shows that the thermostability of Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Dy{sup 3+} is superior than that of commercial phosphor Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Ce{sup 3+}. The outstanding luminescent properties indicate that Ca{sub 3}Sc{sub 2}Si{sub 3}O{sub 12}:Dy{sup 3+} could be a potential white light emission phosphor.

  3. Experience with OpenMP for MADX-SC

    Energy Technology Data Exchange (ETDEWEB)

    D' Imperio, Nicholas [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Montag, Christophe [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Yu, Kwangmin [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Kapin, Valery [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); McIntosh, Eric [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Renshall, Harry [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Schmidt, Frank [European Organization for Nuclear Research (CERN), Geneva (Switzerland)

    2014-07-01

    MADX-SC allows the treatment of frozen space charge using beam-beam elements in a thin lattice, i.e. one can take advantage of the standard set-up of MAD-X lattices without the need for specialized codes for the space-charge (SC) evaluation. The idea is to simulate over many turns without the problem of noise as in the PIC SC codes. For the examples under study, like the PS and RHIC, it would be desirable to simulate up to 1 million turns or more. To this end one had to make an effort to optimize the scalar speed and, most importantly, get a speed-up of approximately a factor of 5 using OpenMP.

  4. Estudo medico da hemoglobinopatia SC em negroides paulistas

    OpenAIRE

    Raquel Ribeiro Gomes

    1988-01-01

    Resumo: A hemoglobinopatia SC é a segunda síndrome falcêmica mais importante no Brasil, devido à sua significativa prevalência entre negróides e também pelas manifestações clínicas apresentadas Apesar disso, ela tem sido pouco estudada em nosso país, não existindo na literatura nacional nenhum trabalho específico sobre essa doença. No presente trabalho, procurou-se investigar o significado médico da doença SC no Estado de são Paulo, analisando-se dois tipos de casuísticas de pacientes SC. Em ...

  5. Experience with OpenMP 1 for MADX-SC

    CERN Document Server

    D’Imperio, N; Yu, K; Kapin, V; McIntosh, E; Renshall, H; Schmidt, F

    2014-01-01

    MADX-SC [1–3] allows the treatment of frozen space charge using beam-beam elements in a thin lattice, i.e. one can take advantage of the standard set-up of MAD-X [4] lattices without the need for specialized codes for the space-charge (SC) evaluation. The idea is to simulate over many turns without the problem of noise as in the PIC 1 SC codes. For the examples under study, like the PS and RHIC, it would be desirable to simulate up to 1 million turns or more. To this end one had to make an effort to optimize the scalar speed and, most importantly, get a speed-up of approximately a factor of 5 using OpenMP [5].

  6. Transport of one SC coil through the village of Meyrin

    CERN Multimedia

    1956-01-01

    In 1952, before CERN was officially founded, two accelerator projects were launched: one for an innovative accelerator to operate at an energy level unequalled at the time, the other for a more standard machine, a Synchro-Cyclotron (SC) to operate at 600 MeV. Design work on the SC was started in 1952 and carried out by teams scattered throughout Europe. Once construction began in 1954, CERN had to arrange road transport for the first of what has since been a long series of spectacular component deliveries, such as those of the machine's two magnetic coils each weighing 60 tonnes and measuring 7.2 metres in diameter. Above, one of them is seen passing through the village of Meyrin. The SC was commissioned in 1957 and was operational for 34 years!

  7. Synthesis and structure of perovskite ScMnO3.

    Science.gov (United States)

    Chen, Haiyan; Yu, Tian; Gao, Peng; Bai, Jianming; Tao, Jing; Tyson, Trevor A; Wang, Liping; Lalancette, Roger

    2013-08-19

    The rare-earth manganites RMnO3 (R = rare earth) are a class of important multiferroics with stable hexagonal structures for small R ion radius (Sc, Lu, Yb, ...). Metastable perovskite phases of these systems possess intriguing electronically driven electrical polarization, but the synthesis of the perovskite phase for the end member ScMnO3 system has proven to be elusive. We report the structure of a new monoclinic P2(1)/n perovskite phase of ScMnO3 synthesized from the hexagonal phase under high-pressure and high-temperature conditions. This extends the small ion region for so-called E-phase electronically driven ferroelectric manganese perovsites.

  8. The {\\sc Majorana Demonstrator} Neutrinoless Double-Beta Decay Experiment

    CERN Document Server

    Abgrall, N; Avignone, F T; Barabash, A S; Bertrand, F E; Boswell, M; Brudanin, V; Busch, M; Caldwell, A S; Chan, Y-D; Christofferson, C D; Combs, D C; Detwiler, J A; Doe, P J; Efremenko, Yu; Egorov, V; Ejiri, H; Elliott, S R; Esterline, J; Fast, J E; Finnerty, P; Fraenkle, F M; Galindo-Uribarri, A; Giovanetti, G K; Goett, J; Green, M P; Gruszko, J; Guiseppe, V E; Gusey, K; Hallin, A L; Hazama, R; Hegai, A; Henning, R; Hoppe, E W; Howard, S; Howe, M A; Keeter, K J; Kidd, M F; Knecht, A; Kochetov, O; Konovalov, S I; Kouzes, R T; LaFerriere, B D; Leon, J; Leviner, L E; Loach, J C; MacMullin, S; Martin, R D; Mertens, S; Mizouni, L; Nomachi, M; Orrell, J L; O'Shaughnessy, C; Overman, N R; Phillips, D G; Poon, A W P; Pushkin, K; Radford, D C; Rielage, K; Robertson, R G H; Ronquest, M C; Schubert, A G; Shanks, B; Shima, T; Shirchenko, M; Snavely, K J; Snyder, N; Steele, D; Strain, J; Suriano, A M; Thompson, J; Timkin, V; Tornow, W; Varner, R L; Vasilyev, S; Vetter, K; Vorren, K; White, B R; Wilkerson, J F; Xu, W; Yakushev, E; Young, A R; Yu, C-H; Yumatov, V

    2013-01-01

    The {\\sc Majorana Demonstrator will search for the neutrinoless double-beta decay of the isotope Ge-76 with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino. The {\\sc Demonstrator} is being assembled at the 4850-foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the {\\sc Demonstrator} and the details of its design.

  9. Sobredentadura total superior implantosoportada Superior total overdenture on implants

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.This is the case of a total maxilla edentulous patient seen in consultation of the "Pedro Ortíz" Clinic Implant of Habana del Este municipality in 2009 and con rehabilitation by prosthesis over osteointegration implants added to stomatology practice in Cuba as an alternative to conventional treatment in patients totally edentulous. We follow a protocol including a surgery or surgical phase, technique without or with flap creation and early or immediate load. This is a male patient aged 56 came to our multidisciplinary consultation worried because he had three prostheses in last two years and any fulfilled the requirements of retention to feel safe and comfortable with prostheses. The final result was the total satisfaction of rehabilitated patient improving its aesthetic and functional quality.

  10. Axonal recordings from medial superior olive neurons obtained from the lateral lemniscus of the chinchilla (Chinchilla laniger).

    Science.gov (United States)

    Bremen, Peter; Joris, Philip X

    2013-10-30

    Interaural time differences (ITDs) are a major cue for localizing low-frequency (sounds. Sensitivity to this cue first occurs in the medial superior olive (MSO), which is thought to perform a coincidence analysis on its monaural inputs. Extracellular single-neuron recordings in MSO are difficult to obtain because (1) MSO action potentials are small and (2) a large field potential locked to the stimulus waveform hampers spike isolation. Consequently, only a limited number of studies report MSO data, and even in these studies data are limited in the variety of stimuli used, in the number of neurons studied, and in spike isolation. More high-quality data are needed to better understand the mechanisms underlying neuronal ITD-sensitivity. We circumvented these difficulties by recording from the axons of MSO neurons in the lateral lemniscus (LL) of the chinchilla, a species with pronounced low-frequency sensitivity. Employing sharp glass electrodes we successfully recorded from neurons with ITD sensitivity: the location, response properties, latency, and spike shape were consistent with an MSO axonal origin. The main difficulty encountered was mechanical stability. We obtained responses to binaural beats and dichotic noise bursts to characterize the best delay versus characteristic frequency distribution, and compared the data to recordings we obtained in the inferior colliculus (IC). In contrast to most reports in other rodents, many best delays were close to zero ITD, both in MSO and IC, with a majority of the neurons recorded in the LL firing maximally within the presumed ethological ITD range.

  11. Thermoelectric performance of functionalized Sc2C MXenes

    KAUST Repository

    Kumar, S.

    2016-07-05

    Functionalization of the MXene Sc2C, which has the rare property to realize semiconducting states for various functionalizations including O, F, and OH, is studied with respect to the electronic and thermal behavior. The lowest lattice thermal conductivity is obtained for OH functionalization and an additional 30% decrease can be achieved by confining the phonon mean free path to 100 nm. Despite a relatively low Seebeck coefficient, Sc2C(OH)2 is a candidate for intermediate-temperature thermoelectric applications due to compensation by a high electrical conductivity and very low lattice thermal conductivity.

  12. Determination of Sc by Ion-exchanger Colorimetry

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Ion-exchanger colorimetry for scandium in the form of ternary color system "Sc(Ⅲ)-CPA-pc-Ac" was developed. The influences of types and grain sizes of resin, adsorption modes and the acidity on the determination were studied systematically, and the optimum operating conditions and the allowable amounts of foreign ions were determined. In comparison with the ordinary solution colorimetry, both of the sensitivity and the selectivity of this ion-exchanger colorimetry are improved obviously. The preliminary uses of this method to the determination of Sc(Ⅲ) in two synthetic samples were satisfied.

  13. Product policy of SC Electrecord S.A.

    Directory of Open Access Journals (Sweden)

    Ph. D. Candidate Cristina Andreescu (Manolache

    2009-12-01

    Full Text Available The global brand has the advantage of the scale economy, facilitates the company image and prestige and sometimes benefits even from its origin country effect. Its use is quite difficult (the semantic variations can impede the use of the same brand. The international brands act as a restriction against standardisation (the product should not be differentiated as there are internationally accepted and recognized brands. This paper makes an overview description of the general market environment, but also of the arket environment of SC ELECTRECORD S.A.; it underlines the product characteristics as well as the commercial diagnosis within SC ELECTRECORD S.A.

  14. Bayesian narrowband interference mitigation in SC-FDMA

    KAUST Repository

    Ali, Anum

    2015-08-12

    This paper presents a novel narrowband interference (NBI) mitigation scheme for SC-FDMA systems. The proposed scheme exploits the frequency domain sparsity of the unknown NBI signal and adopts a low complexity Bayesian sparse recovery procedure. In practice, however, the sparsity of the NBI is destroyed by a grid mismatch between NBI sources and SC-FDMA system. Towards this end, an accurate grid mismatch model is presented and a sparsifying transform is utilized to restore the sparsity of the unknown signal. Numerical results are presented that depict the suitability of the proposed scheme for NBI mitigation.

  15. Radiation protection Group (SC/RP) desperately seeking...

    CERN Multimedia

    A. Hervé, Y. Donjoux / SC

    2006-01-01

    We are trying to trace two transit permits (passavants), which constitute the customs clearance documentation for two 'AD6'portable radiation detectors. The two permits (No. 1308 and No. 1309) were sent in the same internal mail envelope towards the middle of March 2006 but never reached their final destination. After weeks of searching in vain, we are now appealing for your help. If you have these two permits in your possession, please get in touch with us. Many thanks in advance. A.HERVE - SC/RP- ( 163168 / 70927) Y.DONJOUX - SC/RP - (160105 / 73171)

  16. Tetrahedron dynamics in the icosahedral quasicrystals i-ZnMgSc and i-ZnAgSc and the cubic 1/1-approximant Zn6Sc.

    Science.gov (United States)

    Euchner, H; Yamada, T; Rols, S; Ishimasa, T; Kaneko, Y; Ollivier, J; Schober, H; Mihalkovic, M; de Boissieu, M

    2013-03-20

    A comparison of periodic approximants and their quasicrystalline counterparts offers the opportunity to better understand the structure, physical properties and stabilizing mechanisms of these complex phases. We present a combined experimental and molecular dynamics study of the lattice dynamics of the icosahedral quasicrystals i-ZnMgSc and i-ZnAgSc and compare it to recently published results obtained for the cubic 1/1-approximant Zn(6)Sc. Both phases, quasicrystal and approximant, are built up from large atomic clusters which contain a tetrahedral shell at the cluster centre and are packed either quasiperiodically or on a bcc lattice. Using quasielastic neutron scattering and atomic scale simulations, we show that in the quasicrystal the tetrahedra display a dynamics similar to that observed in the 1/1-approximant: the tetrahedra behave as a 'single molecule' and reorient dynamically on a timescale of the order of a few ps. The tetrahedra reorientation is accompanied by a large distortion of the surrounding cluster shells which provide a unique dynamical flexibility to the quasicrystal. However, whereas in the 1/1-approximant the tetrahedron reorientation is observed down to T(c) = 160 K, where a phase transition takes place, in the quasicrystal the tetrahedron dynamics is gradually freezing from 550 to 300 K, similarly to a glassy system.

  17. Genome Sequence of Herpes Simplex Virus 1 Strain SC16

    Science.gov (United States)

    Rastrojo, Alberto; López-Muñoz, Alberto Domingo

    2017-01-01

    ABSTRACT Herpes simplex virus 1 (HSV-1), also known as Human herpesvirus 1, is a highly prevalent human neurotropic pathogen that causes a variety of diseases, including lethal encephalitis. Here, we report the genome sequence of the HSV-1 strain SC16. PMID:28126930

  18. Calibration of the DLP-SC-3300-02 probe

    DEFF Research Database (Denmark)

    Pivnenko, Sergey; Breinbjerg, Olav

    This report douments the calibration measurement of the DLP-SC-3300-02 dual-linearly polarized near-field probe. The measurement comprises radiation pattern, diretivity, gain, spetra of spherial wave coefients, polarization charateristis, and complex channel balance at 41 frequencies, as well...

  19. Programmable SC biquad using one single capacitor bank

    OpenAIRE

    Torralba Silgado, Antonio Jesús; Pérez Vega-Leal, Alfredo; García Franquelo, Leopoldo

    2001-01-01

    This paper presents a new technique for programming SC circuits using a single time-multiplexed capacitor bank, achieving a significant reduction in capacitance area. Simulation results of a programmable biquad low pass filter show the validity of the proposed method.

  20. Toelating Herbasan SC welkom voor dahlia, A. coronaria en narcis

    NARCIS (Netherlands)

    Leeuwen, van P.J.; Koster, A.T.J.; Trompert, J.P.T.

    2005-01-01

    Onlangs is Herbasan SC voor de onkruidbestrijding in onder meer dahlia, narcis en Anemone coronaria toegelaten. PPO ging na hoe het middel het beste is in te zetten. In dit artikel zijn de resultaten van het onderzoek vermeld en een advies voor toepassing

  1. 78 FR 20369 - South Carolina Disaster #SC-00021

    Science.gov (United States)

    2013-04-04

    ... ADMINISTRATION South Carolina Disaster SC-00021 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of South Carolina dated 03/29/2013. Incident: Windsor Green Condo Complex Fire. Incident Period: 03/16/2013....

  2. 77 FR 14700 - Safety Zones; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2012-03-13

    ... notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73 FR 3316... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zones; Swim Around Charleston, Charleston, SC... establish temporary moving safety zones during the Swim Around Charleston, a swimming race occurring on...

  3. 76 FR 38586 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2011-07-01

    ... Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public meeting. But you may... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... establish a temporary moving safety zone during the Swim Around Charleston, a swimming race occurring...

  4. 78 FR 54583 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2013-09-05

    ..., telephone 202-366-9826. SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... temporary moving safety zone during the Swim Around Charleston, a swimming race occurring on waters of...

  5. 77 FR 51471 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2012-08-24

    ... rulemaking (NPRM) entitled Safety Zone; Swim Around Charleston, Charleston, SC in the Federal Register (77 FR...: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston,...

  6. South Carolina's SC LENDS: Optimizing Libraries, Transforming Lending

    Science.gov (United States)

    Hamby, Rogan; McBride, Ray; Lundberg, Maria

    2011-01-01

    Since SC LENDS started operating in June 2009, more public libraries have come on board. All of this on the back end connects to a Mozilla-based staff client that has distributions for Mac OS X and Microsoft Windows, using SSL encryption to keep communications secure and private between remote libraries and the servers hosted at a high-end…

  7. Envíos Confianza, S.C.

    OpenAIRE

    Banco Interamericano de Desarrollo (BID); S.C. Envíos Confianza

    2009-01-01

    Presentación acerca de Envíos Confianza, S.C., en el cual da a conocer su historia, misión, visión, valores, efecto de las remesas en comunidades e impacto de la crisis financiera. Además, señala la proyección para el 2009-2011.

  8. M.Sc. in Civil and Structural Engineering

    DEFF Research Database (Denmark)

    The catalogue contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short candidate projects as well as regular 3rd semester...... projects at the M.Sc. programme in Civil and Structural Engineering....

  9. M.Sc. in Civil and Structural Engineering

    DEFF Research Database (Denmark)

    The following pages contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short master projects as well as regular 3rd...... semester projects at the M.Sc. programme in Civil and Structural Engineering....

  10. M.Sc. in Civil and Structural Engineering

    DEFF Research Database (Denmark)

    This catalogue contains a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short candidate projects as well as regular 3rd...... semester projects at the M.Sc. programme in Civil and Structural Engineering....

  11. M.Sc. in Civil and Structural Engineering

    DEFF Research Database (Denmark)

    Clausen, Johan

    The report contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short candidate projects as well as regular 3rd semester...... projects at the M.Sc. programme in Civil and Structural Engineering....

  12. 44gSc from metal calcium targets for PET

    DEFF Research Database (Denmark)

    Severin, Gregory; Gagnon, K.; Engle, J. W.

    2012-01-01

    A low-cost and efficient method for producing pre-clinical scale quantities of 44gSc is presented. Production involves proton irradiation of natural unenriched calcium metal followed by rapid separation of radioscandium from the target using hydroxmate functionalized resin.© 2012 American Institu...

  13. Effect of Sc on Precipitation Hardening of AlSi6Mg Alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effect of Sc on precipitation hardening of AlSi6Mg was studied. Zr was previously reported that it increased the effectiveness of Sc in wrought aluminum in many areas so Zr was also used together with Sc in this study.Different levels of Sc and Zr additions were added to AlSi6Mg before casting in the permanent mold. The samples were precipitation hardened at different aging temperatures and for various aging time before testing for tensile strength and hardness. It was found that Sc addition into Al6SiMg can change its response to age hardening. Additions of Sc and Sc with Zr increased both yield strength and hardness for both aging temperatures. In addition, Sc was found to modify eutectic Si to obtain fibrous morphology. This effect of Sc on eutectic silicon modification has never been reported before.

  14. Role of cell death in the propagation of PrP(Sc) in immune cells.

    Science.gov (United States)

    Takahashi, Kenichi; Inoshima, Yasuo; Ishiguro, Naotaka

    2015-03-01

    A number of studies have suggested that macrophages, dendritic cells, and follicular dendritic cells play an important role in the propagation of PrP(Sc). Both accumulation and proteolysis of PrP(Sc) have been demonstrated in peripheral macrophages. Macrophages may act as reservoirs for PrP(Sc) particles if the cells die during transient PrP(Sc) propagation. However, whether cell death plays a role in PrP(Sc) propagation in macrophages remains unclear. In this study, we investigated the possibility of propagation and transmission of PrP(Sc) between dead immune cells and living neural cells. We found that under specific conditions, transient PrP(Sc) propagation occurs in dead cells, indicating that interaction between PrP(C) and PrP(Sc) on plasma membrane lipid rafts might be important for PrP(Sc) propagation. Co-culturing of killed donor PrP(Sc)-infected macrophages with recipient N2a-3 neuroblastoma cells accelerated PrP(Sc) transmission. Our results suggest that cell death may play an important role in PrP(Sc) propagation, whereas transient PrP(Sc) propagation in macrophages has little effect on PrP(Sc) transmission.

  15. Update on the NSF PAARE Program at SC State

    Science.gov (United States)

    Walter, Donald K.; Ajello, Marco; Brittain, Sean D.; Cash, Jennifer; Hartmann, Dieter; Ho, Shirley; Howell, Steve B.; King, Jeremy R.; Leising, Mark D.; Smith, Daniel M.

    2017-01-01

    We report on results from our NSF PAARE program during Year 2 of the project. Our partnership under this PAARE award includes South Carolina State University (a Historically Black College/University), Clemson University (a Ph.D. granting institution) as well as individual investigators at NASA Ames and Carnegie Mellon University. Our recent work on variable and peculiar stars, work with the Kepler Observatory and our educational products in cosmology for non-STEM majors will be presented. We have successfully piloted sharing our teaching resources by offering an upper-level astrophysics course taught at Clemson via video conferencing , allowing a graduating senior from SC State to take a course not available through his home institution. Additionally, we are working on a memorandum of agreement between the two institutions that will allow for the seamless transfer of an undergraduate from SC State to Clemson’s graduate program in physics and astronomy. Our curriculum work includes new web-based cosmology activities and laboratory experiments. SC State undergraduates are reporting at this conference on their work with the light curves of semiregular variables using Kepler data. Additionally, we are heavily involved in the Citizen CATE Experiment. A PAARE scholarship student from SC State and the PAARE PI traveled to Indonesia for the March 2016 solar eclipse. Their results are also being presented elsewhere at this conference (see Myles McKay’s poster). Support for this work includes our NSF PAARE award AST-1358913 as well as resources and support provided by Clemson University and the National Optical Astronomy Observatory. Additional support has been provided by the South Carolina Space Grant Consortium and from NASA to SC State under awards NNX11AB82G and NNX13AC24G. CATE work has been supported by NASA SMD award NNX16AB92A to the National Solar Observatory. Additional details can be found at: http://physics.scsu.edu

  16. Paso superior en una ladera

    Directory of Open Access Journals (Sweden)

    Bender, O.

    1965-07-01

    Full Text Available The Redwood highway, through the Californian forest, runs on a viaduct, as it crosses a mountain slope of about 45° inclination. The firm ground is fairly deep, and as an additional constructional difficulty, it was necessary to respect the natural beauty of the countryside. A structure of portal frames were built, forming a number of short spans. These spans were bridged with metal girders, on which a 19 m wide deck was placed. The columns are hollow and have a transversal cross beam, to join each pair. There was difficulty in excavating the foundations for the columns, as it was necessary to dig through the soft top soil, and also prevent this soil from hurting the trunks of the forest trees. Another significant difficulty in the construction of this viaduct was the access to the working site, since there were no suitable platforms from which to operate the appropriate machinery. This made it necessary to do a lot of the work by manual operation. As one of the edges of the deck is very close to the mountain side, a supporting beam was erected on this side. It was made of concrete, on metal piles. The formwork for the deck structure was placed on the concrete stems of the supporting piles.La autopista denominada Redwood (California salva, con un paso superior, la ladera de un bosque cuya pendiente es del 1/1. El terreno firme se halla a bastante profundidad, añadiéndose, a los naturales problemas de la construcción, el imperativo de respetar la belleza agreste del paraje. La solución adoptada consiste en una estructura porticada, con varios tramos de pequeñas luces, salvados con vigas metálicas, sobre los que se coloca la losa del tablero, de 19 m de anchura total. Los soportes están constituidos por pórticos de dos montantes huecos (con bases de hormigón en masa por debajo del suelo, hasta el firme coronados por un cabezal. La perforación de pozos para el hormigonado de los montantes presentaba la dificultad de atravesar el terreno

  17. Pseudodisplacements of superior vena cava catheter in the persistent left superior vena cava

    Energy Technology Data Exchange (ETDEWEB)

    Jantsch, H.; Draxler, V.; Muhar, U.; Schlemmer, M.; Waneck, R.

    1983-01-01

    Pseudodisplacement of a left sided superior vena cava catheter in a persistent superior vena cava may be expected in adults in 0,37% and in a group of children with congenital heart disease in 2,5%. Embryology, anatomy and clinical implications is discussed on the basis of our own cases. The vena cava superior sinistra persitents is depending on a sufficient calibre a suitable vessel for a superior cava catheter.

  18. Effect of solution treatment on the aging processes of Al-Sc alloys

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Toropova, L.S. (AN SSSR, Moscow. Inst. Metallurgii); Dutkiewicz, J.; Salawa, J. (Polish Academy of Sciences, Cracow. Inst. for Metal Research)

    1984-10-01

    The kinetics of aging process of two Al-Sc alloys containing 0.2 and 0.5 wt% Sc, respectively was investigated using electrical resistivity and hardness measurements. Transmission electron micrographs of quenched samples show Sc-rich precipitates, especially Al/sub 3/Sc precipitates. The addition of Sc to Al causes the strongest hardening effect during aging in relation to other alloying additions. Cast Al-Sc alloys and water quenched ones from solid solubility range show very similiar age-hardening curves.

  19. Pegada ecológica de uma instituição do ensino superior portuguesa

    Directory of Open Access Journals (Sweden)

    Susana Paixão

    2012-06-01

    Full Text Available O equilíbrio entre a vida humana e o ambiente só é possível se, entre outros aspetos, a vivência dos seres humanos for realizada em simbiose ambiental, ou seja, da forma mais ecológica possível. De forma a constatar a existência dessa simbiose, criaram-se diversas ferramentas para avaliar a sustentabilidade, tal como a Pegada Ecológica (PE. O presente estudo tem como principal objetivo o cálculo da PE da Escola Superior de Tecnologia da Saúde de Coimbra (ESTeSC, comparando os valores obtidos com os dois estudos anteriormente efetuados com o mesmo âmbito. O questionário que foi disponibilizado à amostra foi adaptado do existente na plataforma www.myfootprint.org. Comparando os resultados obtidos com anos anteriores, é possível verificar que a PE da ESTeSC desde 2009 tem vindo a diminuir na generalidade dos grupos estudados. Apenas o grupo dos docentes aumentou a sua PE desde o ano de 2010, sendo que a média da ESTeSC no ano de 2011 foi de 4,8 hectares globais.

  20. Two anionically derivatized scandium oxoselenates(IV): ScF[SeO3] and Sc2O2[SeO3

    Science.gov (United States)

    Greiner, Stefan; Chou, Sheng-Chun; Schleid, Thomas

    2017-02-01

    Scandium fluoride oxoselenate(IV) ScF[SeO3] and scandium oxide oxoselenate(IV) Sc2O2[SeO3] could be synthesized through solid-state reactions. ScF[SeO3] was obtained phase-pure, by reacting mixtures of Sc2O3, ScF3 and SeO2 (molar ratio: 1:1:3) together with CsBr as fluxing agent in corundum crucibles embedded into evacuated glassy silica ampoules after firing at 700 °C for seven days. Sc2O2[SeO3] first emerged as by-product during the attempts to synthesize ScCl[SeO3] following aforementioned synthesis route and could later be reproduced from appropriate Sc2O3/SeO3 mixtures. ScF[SeO3] crystallizes monoclinically in space group P21/m with a=406.43(2), b =661.09(4), c=632.35(4) pm, β=93.298(3)° and Z=2. Sc2O2[SeO3] also crystallizes in the monoclinic system, but in space group P21/n with a=786.02(6), b=527.98(4), c=1086.11(8) pm, β=108.672(3)° for Z=4. The crystal structures of both compounds are strongly influenced by the stereochemically active lone pairs of the ψ1-tetrahedral [SeO3]2- anions. They also show partial structures, where the derivatizing F- or O2- anions play an important role. For ScF[SeO3] chains of the composition 2+ ∞ 1[FSc2/2] form from connected [FSc2]5+ dumbbells, while [OSc3]7+ pyramids and [OSc4]10+ tetrahedra units are condensed to layers according to 2+ ∞ 2[O2Sc2 ] in Sc2O2[SeO3].

  1. Conversion from Li2SO4 to Li2S@C on carbon paper matrix: A novel integrated cathode for lithium-sulfur batteries

    Science.gov (United States)

    Wang, D. H.; Xie, D.; Yang, T.; Zhong, Y.; Wang, X. L.; Xia, X. H.; Gu, C. D.; Tu, J. P.

    2016-11-01

    Integral construction of lithium sulfide (Li2S) cathode is indispensable and vital for developing high-performance lithium-sulfur (Li-S) batteries. Herein we have demonstrated a facile strategy for fabricating free-standing carbon paper supported Li2S@C (P-Li2S@C) integrated cathode. The P-Li2S@C cathode is synthesized through simple pyrolysis of low-cost lithium sulfate (Li2SO4) and chitosan, and embedded in the double carbon matrixes with carbon paper support and outer CVD-carbon layer. Li2S nanoparticles are homogeneously dispersed in the above designed double carbon matrixes. The P-Li2S@C cathode exhibits an initial discharge capacity of 820 mAh g-1 at 0.1 C and still maintains 430 mAh g-1after 100 cycles, superior to the P-Li2S counterpart (480 mAh g-1 at 0.1 C and 150 mAh g-1 after 100 cycles). Our research verifies the effectiveness of double carbon modification on the Li2S, especially, the outer carbon coating not only improves the electrical conductivity of electrode, but also further prohibits the "shuttle effect" of polysulfides.

  2. Superiority in value and the repugnant conclusion

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint

    2007-01-01

    James Griffin has considered a weak form of superiority in value a possible remedy to the Repugnant Conclusion. In this paper, I demonstrate that, in a context where value is additive, this weaker form collapses into a stronger form of superiority. And in a context where value is non-additive, weak...... superiority does not amount to a radical value difference at all. I then spell out the consequences of these results for different interpretations of Griffin's suggestion regarding population ethics. None of them comes out very successful, but perhaps they nevertheless retain some interest....

  3. Structural, elastic and thermodynamic properties of Ti2SC

    Indian Academy of Sciences (India)

    Hongzhi Fu; Wenfang Liu; Tao Gao

    2011-12-01

    The structural parameters, elastic constants and thermodynamic properties of Ti2SC were investigated under pressure and temperature by using first-principles plane-wave pseudopotential density functional theory within the generalized gradient approximation. The obtained results are in agreement with the available experimental data. The bulk moduli along the - and -axes, $B_{a}$ and $B_{c}$, almost linearly increase with pressure, and the former is always smaller than the latter. The ratio of $B_{c}/B_{a}$ has a trend of gradual increase as the pressure increases. It is found that the elastic constants, anisotropy and Debye temperature of Ti2SC increase with pressure, while axial compressibility along the - and -axes decreases with pressure. The thermal properties including the equation of state, the Grüneisen parameter , the anisotropies $\\Delta_{p}, \\Delta_{S1}$ and $\\Delta_{S2}$, and the heat capacity are estimated at various pressures and temperatures.

  4. Dynamical stability and evolution of the discs of Sc galaxies

    CERN Document Server

    Fuchs, B

    1997-01-01

    We examine the local stability of galactic discs against axisymmetric density perturbations with special attention to the different dynamics of the stellar and gaseous components. In particular the discs of the Milky Way and of NGC 6946 are studied. The Milky Way is shown to be stable, whereas the inner parts of NGC 6946, a typical Sc galaxy from the Kennicutt (1989) sample, are dynamically unstable. The ensuing dynamical evolution of the composite disc is studied by numerical simulations. The evolution is so fierce that the stellar disc heats up dynamically on a short time scale to such a degree, which seems to contradict the morphological appearance of the galaxy. The star formation rate required to cool the disc dynamically is estimated. Even if the star formation rate in NGC 6946 is at present high enough to meet this requirement, it is argued that the discs of Sc galaxies cannot sustain such a high star formation rate for longer periods.

  5. A Study on the Fluorescence System of Sc-BPMPHD-CTMAB and Its Analytical Application

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ Introduction The fluorescence of Sc3+ itself in solution is not observed. After complexed with an organic ligand with a chromophore, Sc3+ makes the ligand, which has no or has weak fluorescence, emit strong fluorescence.

  6. Status of Simulation Tools for the ILD ScECAL

    OpenAIRE

    Kotera, Katsushige; anduze, marc; Boudry, Vincent; Brient, Jean-Claude; Jeans, Daniel; Kawagoe, Kiyotomo; Miyamoto, Akiya; de Freitas, Paulo Mora; Musat, Gabriel; Ono, Hiroaki; Takeshita, Tohru; Uozumi, Satoru

    2010-01-01

    The scintillator-strip electromagnetic calorimeter (ScECAL) is one of the calorimeter technic for the ILC. To achieve the fine granularity from the strip-segmented layers the strips in odd layers are orthogonal with respect to those in the even layers. In order to extract the best performance from such detector concept, a special reconstruction method and simulation tools are being developed in ILD collaboration. This manuscript repots the status of developing of those tools.

  7. Metastable Al-Sc phase diagram in aluminium rich region

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Toropova, L.S.; Bykov, Yu.G.; Gushchina, F.L.; Elagin, V.I.; Filatov, Yu.A.

    1982-12-01

    An aluminium rich part of binary metastable phase diagram Al-Sc for 100 deg/s alloy cooling rate under crystallization is studied. Eutectic horizontal in the metastable diagram is 4 deg lower as compared to the equilibrium one, scandium concentration in the eutectic point makes up approximately 0.8%, the maximum solubility is 0.6%. Maximum cast grain refining in aluminium under crystallization at the rate of 100 deg/s is attained at 0.6% scandium content.

  8. Millian superiorities and the repugnant conclusion

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint

    2008-01-01

    James Griffin has considered a form of superiority in value that is weaker than lexical priority as a possible remedy to the Repugnant Conclusion. In this article, I demonstrate that, in a context where value is additive, this weaker form collapses into the stronger form of superiority. And in a ......James Griffin has considered a form of superiority in value that is weaker than lexical priority as a possible remedy to the Repugnant Conclusion. In this article, I demonstrate that, in a context where value is additive, this weaker form collapses into the stronger form of superiority...... of these results for different interpretations of Griffin's suggestion regarding population ethics. None of them comes out very successful, but perhaps they nevertheless retain some interest....

  9. Measuring Financial Gains from Genetically Superior Trees

    Science.gov (United States)

    George Dutrow; Clark Row

    1976-01-01

    Planting genetically superior loblolly pines will probably yield high profits.Forest economists have made computer simulations that predict financial gains expected from a tree improvement program under actual field conditions.

  10. Superior mesenteric artery syndrome causing growth retardation

    Directory of Open Access Journals (Sweden)

    Halil İbrahim Taşcı

    2013-03-01

    Full Text Available Superior mesenteric artery syndrome is a rare and lifethreateningclinical condition caused by the compressionof the third portion of the duodenum between the aortaand the superior mesenteric artery’s proximal part. Thiscompression may lead to chronic intermittent, acute totalor partial obstruction. Sudden weight-loss and the relateddecrease in the fat tissue are considered to be the etiologicalreason of acute stenosis. Weight-loss accompaniedby nausea, vomiting, anorexia, epigastric pain, andbloating are the leading complaints. Barium radiographs,computerized tomography, conventional angiography,tomographic and magnetic resonance angiography areused in the diagnosis. There are medical and surgical approachesto treatment. We hereby present the case ofa patient with superior mesenteric artery syndrome withdelayed diagnosis.Key words: superior mesenteric artery syndrome, nausea-vomiting, anorexia

  11. QUALITY MANAGEMENT OF BAKERY PRODUCTS: A CASE STUDY IN SC

    Directory of Open Access Journals (Sweden)

    Nicoleta- Luminiţa STRÂMBEANU RISTEA

    2013-01-01

    Full Text Available The paper aimed to present the benefits of implementing HACCP (Hazard Analysis and Critical Control Points to company S.C. "DOBRE AND SONS" S.R.L. Constanta, Romania. The data have been provided by the above mentioned manufacturer. The objectives of S.C. "DOBRE AND SONS" S.R.L. are protecting the health of the consumers of the products and their satisfaction regarding the consumption of products that are nutritional, tasty, fresh, free from microbiological, chemical and physical hazard, as well as possessing stable properties during the validity for consumption. In this respect, there has been implemented and maintained an integrated management system of food quality and safety according to SR EN ISO 9001:2008, SR EN ISO 22000:2005 and according to IFS standard, version 5/2007, which consists of determining the potential biological, chemical and physical hazards that might affect the safety of bread and bakery products, or the health of the consumer. HACCP team is analyzing hazard using one of the recommended techniques: brainstorming or the cause - effect diagram. In conclusion, the company S.C. "DOBRE AND SONS" S.R.L. Constanta, Romania provides awareness and employee involvement at all levels in achieving the appointed objectives.

  12. Charleston Harbor, SC, Regional Sediment Management Study; Beneficial Use of Dredged Material through Nearshore Placement

    Science.gov (United States)

    2017-05-01

    ER D C/ CH L TR -1 7- 7 Regional Sediment Management (RSM) Program Charleston Harbor, SC, Regional Sediment Management Study...acwc.sdp.sirsi.net/client/default. Regional Sediment Management (RSM) Program ERDC/CHL TR-17-7 May 2017 Charleston Harbor, SC, Regional Sediment...454632, “Charleston Harbor, SC; Regional Sediment Management Study” ERDC/CHL TR-17-7 ii Abstract The 2015 Charleston Harbor, SC, final

  13. A study of Al-Sc-Zr alloys in the aluminum-rich region

    Energy Technology Data Exchange (ETDEWEB)

    Toropova, L.S.; Kamardinkin, A.N.; Kindzhibalo, V.V.; Tyvanchuk, A.T. (AN SSSR, Institut Metallurgii, Moscow (USSR))

    1990-12-01

    Alloys in the ternary system Al-Sc-Zr along a section of approximately 1.0 pct Sc and 0.8 pct Zr were investigated by X-ray diffraction and electron probe analyses. It is found that phases Al3Sc and Al3Zr are in equilibrium with the alpha solid solution of aluminum. The contents of zirconium and scandium in the phase Al3Sc are determined as a function of their concentrations in the alloy.

  14. Leiomyosarcoma of the superior vena cava.

    Science.gov (United States)

    de Chaumont, Arthus; Pierret, Charles; de Kerangal, Xavier; Le Moulec, Sylvestre; Laborde, François

    2014-08-01

    Leiomyosarcoma of the superior vena cava is a very rare tumor and only a few cases have been reported, with various techniques of vascular reconstruction. We describe a new case of leiomyosarcoma of the superior vena cava in a 61-year-old woman with extension to the brachiocephalic arterial trunk. Resection and vascular reconstruction were performed using, respectively, polytetrafluoroethylene and polyethylene terephtalate vascular grafts.

  15. Superior mesenteric artery compression syndrome - case report

    OpenAIRE

    Paulo Rocha França Neto; Rodrigo de Almeida Paiva; Antônio Lacerda Filho; Fábio Lopes de Queiroz; Teon Noronha

    2011-01-01

    Superior mesenteric artery syndrome is an entity generally caused by the loss of the intervening mesenteric fat pad, resulting in compression of the third portion of the duodenum by the superior mesenteric artery. This article reports the case of a patient with irremovable metastatic adenocarcinoma in the sigmoid colon, that evolved with intense vomiting. Intestinal transit was carried out, which showed important gastric dilation extended until the third portion of the duodenum, compatible wi...

  16. Effect of ScAl/sub 3/ phase dispersity on hardening of A1-6. 3% Mg-0. 21% Sc alloy

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Bykov, Y.G.; Toropova, L.S.

    1985-09-01

    This paper reports on attempts to evaluate the quantitatively separate influence exerted on the hardening of an aluminum alloy containing 6.3% Mg and 0.21% Sc by both particles of the ScAl/sub 3/ phase exhibiting a different degree of dispersity and also the substructure which is formed in the alloy after hot deformation. The binary aluminum alloy containing 6.3% of Mg after hot deformation has a fully recrystallized structure, while the aluminum alloy containing 6.5% of Mg and Sc is recrystallized. It is concluded that: the magnitude of substructure hardening of the A1-6.3% Mg-0.21% Sc alloy is similar, irrespective of the dispersity of coherent ScAl/sub 3/ particles; and, hardening of the alloy, which is governed by coherent ScAl/sub 3/-phase segregations less than 20 mm in diameter, significantly exceeds the effect of substructure hardening.

  17. Crystal fields of dilute Tb, Dy, or Er in Sc obtained by magnetization measurements

    DEFF Research Database (Denmark)

    Høg, J.; Touborg, P.

    1976-01-01

    Crystal-field parameters for dilute Sc-Tb, Sc-Dy, and Sc-Er alloys have been obtained by fitting theoretical expressions to the experimentally measured paramagnetic susceptibility. The initial susceptibility was measured and corrected for the effects of ordering at the lowest temperatures in the ...

  18. Preparation and characterization of Sc doped MgB2 wires

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Burdusel, M.

    2016-01-01

    The in-situ technique was used to manufacture scandium (Sc) doped MgB2 wires in a composite Cu–Nb sheath. After reaction at 700 °C, at most 1 at.% Mg was replaced by Sc in the MgB2 phase, without significant influence on its superconducting transition temperature. For higher Sc concentrations...

  19. File list: InP.PSC.10.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 35242 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.PSC.10.AllAg.EpiSC.bed ... ...InP.PSC.10.AllAg.EpiSC mm9 Input control Pluripotent stem cell EpiSC SRX590285,SRX5

  20. File list: InP.PSC.50.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 90285 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.PSC.50.AllAg.EpiSC.bed ... ...InP.PSC.50.AllAg.EpiSC mm9 Input control Pluripotent stem cell EpiSC SRX535242,SRX5

  1. File list: InP.PSC.20.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 90285 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.PSC.20.AllAg.EpiSC.bed ... ...InP.PSC.20.AllAg.EpiSC mm9 Input control Pluripotent stem cell EpiSC SRX535242,SRX5

  2. File list: His.PSC.10.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 0286,SRX535238 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.10.AllAg.EpiSC.bed ... ...His.PSC.10.AllAg.EpiSC mm9 Histone Pluripotent stem cell EpiSC SRX590288,SRX535240,

  3. File list: Unc.PSC.05.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 074908,SRX1074905 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.05.AllAg.EpiSC.bed ... ...Unc.PSC.05.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1

  4. File list: His.PSC.50.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 909,SRX1074906 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.50.AllAg.EpiSC.bed ... ...His.PSC.50.AllAg.EpiSC mm9 Histone Pluripotent stem cell EpiSC SRX535239,SRX535240,

  5. File list: InP.PSC.05.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 35242 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.PSC.05.AllAg.EpiSC.bed ... ...InP.PSC.05.AllAg.EpiSC mm9 Input control Pluripotent stem cell EpiSC SRX590285,SRX5

  6. File list: Unc.PSC.50.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 074905,SRX1074908 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.50.AllAg.EpiSC.bed ... ...Unc.PSC.50.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1

  7. File list: His.PSC.05.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 4916,SRX590286 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.05.AllAg.EpiSC.bed ... ...His.PSC.05.AllAg.EpiSC mm9 Histone Pluripotent stem cell EpiSC SRX590288,SRX535240,

  8. File list: Unc.PSC.20.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 074908,SRX1074905 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.20.AllAg.EpiSC.bed ... ...Unc.PSC.20.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1

  9. File list: His.PSC.20.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available 4906,SRX535241 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.20.AllAg.EpiSC.bed ... ...His.PSC.20.AllAg.EpiSC mm9 Histone Pluripotent stem cell EpiSC SRX535239,SRX661083,

  10. Overview of 2009 IEC/TC SC 77C Plenary Meeting%2009 IEC/TC SC 77C年会

    Institute of Scientific and Technical Information of China (English)

    孟萃

    2009-01-01

    介绍了在法国召开的2009 IEC/TC SC 77C分技术委员会工作组会议讨论的IEC 61000-4-35、IEC 6100-5-9、IEC 6100-5-8三个标准项目实施情况、标准维护需求及新的技术工作.

  11. Determining auditory-evoked activities from multiple cells in layer 1 of the dorsal cortex of the inferior colliculus of mice by in vivo calcium imaging.

    Science.gov (United States)

    Ito, Tetsufumi; Hirose, Junichi; Murase, Kazuyuki; Ikeda, Hiroshi

    2014-11-24

    Layer 1 of the dorsal cortex of the inferior colliculus (DCIC) is distinguished from other layers by its cytoarchitecture and fiber connections. However, the information of the sound types represented in layer 1 of the DCIC remains unclear because placing electrodes on such thin structures is challenging. In this study, we utilized in vivo calcium imaging to assess auditory-evoked activities in multiple cells in layer 1 of DCIC and to characterize sound stimuli producing strong activity. Most cells examined showed strong responses to broad-band noise and low-frequency tone bursts of high sound intensity. In some cases, we successfully obtained frequency response areas, which are receptive fields to tone frequencies and intensities, and ~30% of these showed V-shape tunings. This is the first systematic study to record auditory responses of cells in layer 1 of DCIC. These results indicate that cells in this area are selective to tones with low frequency, implying the importance of such auditory information in the neural circuitry of layer 1 of DCIC.

  12. Enhancement of acoustic evoked potentials and impairment of startle reflex induced by reduction of GABAergic control of the neural substrates of aversion in the inferior colliculus.

    Science.gov (United States)

    Nobre, Manoel Jorge; Sandner, Guy; Brandão, Marcus Lira

    2003-10-01

    The neural network of the inferior colliculus (IC), implicated in the generation of defensive behavior to aversive acoustic stimuli, is under tonic GABAergic control. Dopamine also seems to have a modulatory role in these neural circuits. It is still unclear how such changes in transmission of acoustic information influence the motor expression of the defensive behavior. Startle reaction to a sudden noise has been used as an effective way to measure the motor reactivity of rats to fearful acoustic stimuli. In this work we examined the processing of sensorial information--assessed by the recording of auditory evoked potentials (AEP)--and the behavioral effects--evaluated by the freezing and startle responses--during the reduction of GABA levels caused by microinjections of semicarbazide (SMC, 6 microg/0.2 microl), a glutamic acid decarboxylase inhibitor, into the IC. These data were compared to the effects of the overall arousal elicited by apomorphine (APO, 0.5 mg/kg, i.p.). The results obtained show that IC microinjections of SMC induced freezing behavior, enhanced the AEP and impaired the startle reaction to a loud sound. On the other hand, APO changed neither the AEP nor the startle in the same experimental conditions. These results suggest that the release of GABAergic control of the neural substrates of aversion in the IC results in an increased processing of auditory information along with an inhibitory influence on the motor pathways responsible for the startle response.

  13. Role of frequency band integration in sharpening frequency tunings of the inferior colliculus neurons in the big brown bat, Eptesicus fuscus

    Institute of Scientific and Technical Information of China (English)

    WU Feijian; CHEN Qicai; JEN Philip H.S.; SHEN Junxian

    2004-01-01

    By means of a particular two-tone stimulation paradigm in combination of using a pair of electrodes for simultaneously recording from two inferior colliculus (IC) neurons, the current in vivo study is undertaken to explore the role of frequency band integration (FBI) in sharpening of frequency tuning in the big brown bat, Eptesicus fuscus. Three major results are found: (1) The paired neurons correlated to FBI are located not only within the same frequency filter bandwidth (FFB), but also across different FFBs. The relations of their frequency tuning curves (FTCs) are mainly of two types: the flank-overlapped and overlaid patterns. (2) Although the sharpness of FTCs between paired neurons is mutual, the sharpening efficiency of neurons located within the same FFB is higher than that of neurons across FFBs, and the FTCs of neurons with the best frequencies (BF) of 20-30 kHz are most strongly sharpened. (3) The strength of FBI is weak near the BF but gradually increased with frequencies away from the BF of sound stimuli. This suggests that the dynamical FBI of the IC neurons located within and across the FFBs might be involved in the formation of functional FFB structures.

  14. Effects of pulse phase duration and location of stimulation within the inferior colliculus on auditory cortical evoked potentials in a guinea pig model.

    Science.gov (United States)

    Neuheiser, Anke; Lenarz, Minoo; Reuter, Guenter; Calixto, Roger; Nolte, Ingo; Lenarz, Thomas; Lim, Hubert H

    2010-12-01

    The auditory midbrain implant (AMI), which consists of a single shank array designed for stimulation within the central nucleus of the inferior colliculus (ICC), has been developed for deaf patients who cannot benefit from a cochlear implant. Currently, performance levels in clinical trials for the AMI are far from those achieved by the cochlear implant and vary dramatically across patients, in part due to stimulation location effects. As an initial step towards improving the AMI, we investigated how stimulation of different regions along the isofrequency domain of the ICC as well as varying pulse phase durations and levels affected auditory cortical activity in anesthetized guinea pigs. This study was motivated by the need to determine in which region to implant the single shank array within a three-dimensional ICC structure and what stimulus parameters to use in patients. Our findings indicate that complex and unfavorable cortical activation properties are elicited by stimulation of caudal-dorsal ICC regions with the AMI array. Our results also confirm the existence of different functional regions along the isofrequency domain of the ICC (i.e., a caudal-dorsal and a rostral-ventral region), which has been traditionally unclassified. Based on our study as well as previous animal and human AMI findings, we may need to deliver more complex stimuli than currently used in the AMI patients to effectively activate the caudal ICC or ensure that the single shank AMI is only implanted into a rostral-ventral ICC region in future patients.

  15. Acute and Long-Term Effects of Noise Exposure on the Neuronal Spontaneous Activity in Cochlear Nucleus and Inferior Colliculus Brain Slices

    Directory of Open Access Journals (Sweden)

    Moritz Gröschel

    2014-01-01

    Full Text Available Noise exposure leads to an immediate hearing loss and is followed by a long-lasting permanent threshold shift, accompanied by changes of cellular properties within the central auditory pathway. Electrophysiological recordings have demonstrated an upregulation of spontaneous neuronal activity. It is still discussed if the observed effects are related to changes of peripheral input or evoked within the central auditory system. The present study should describe the intrinsic temporal patterns of single-unit activity upon noise-induced hearing loss of the dorsal and ventral cochlear nucleus (DCN and VCN and the inferior colliculus (IC in adult mouse brain slices. Recordings showed a slight, but significant, elevation in spontaneous firing rates in DCN and VCN immediately after noise trauma, whereas no differences were found in IC. One week postexposure, neuronal responses remained unchanged compared to controls. At 14 days after noise trauma, intrinsic long-term hyperactivity in brain slices of the DCN and the IC was detected for the first time. Therefore, increase in spontaneous activity seems to develop within the period of two weeks, but not before day 7. The results give insight into the complex temporal neurophysiological alterations after noise trauma, leading to a better understanding of central mechanisms in noise-induced hearing loss.

  16. Acute and long-term effects of noise exposure on the neuronal spontaneous activity in cochlear nucleus and inferior colliculus brain slices.

    Science.gov (United States)

    Gröschel, Moritz; Ryll, Jana; Götze, Romy; Ernst, Arne; Basta, Dietmar

    2014-01-01

    Noise exposure leads to an immediate hearing loss and is followed by a long-lasting permanent threshold shift, accompanied by changes of cellular properties within the central auditory pathway. Electrophysiological recordings have demonstrated an upregulation of spontaneous neuronal activity. It is still discussed if the observed effects are related to changes of peripheral input or evoked within the central auditory system. The present study should describe the intrinsic temporal patterns of single-unit activity upon noise-induced hearing loss of the dorsal and ventral cochlear nucleus (DCN and VCN) and the inferior colliculus (IC) in adult mouse brain slices. Recordings showed a slight, but significant, elevation in spontaneous firing rates in DCN and VCN immediately after noise trauma, whereas no differences were found in IC. One week postexposure, neuronal responses remained unchanged compared to controls. At 14 days after noise trauma, intrinsic long-term hyperactivity in brain slices of the DCN and the IC was detected for the first time. Therefore, increase in spontaneous activity seems to develop within the period of two weeks, but not before day 7. The results give insight into the complex temporal neurophysiological alterations after noise trauma, leading to a better understanding of central mechanisms in noise-induced hearing loss.

  17. Molecular and functional characterization of peptidoglycan-recognition protein SC2 (PGRP-SC2) from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.

    Science.gov (United States)

    Gan, Zhen; Chen, Shannan; Hou, Jing; Huo, Huijun; Zhang, Xiaolin; Ruan, Baiye; Laghari, Zubair Ahmed; Li, Li; Lu, Yishan; Nie, Pin

    2016-07-01

    PGRP-SC2, the member of PGRP family, plays an important role in regulation of innate immune response. In this paper, a PGRP-SC2 gene of Nile tilapia, Oreochromis niloticus (designated as On-PGRP-SC2) was cloned and its expression pattern under the infection of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for amidase activity were detected in the deduced amino acid sequence of On-PGRP-SC2. In healthy tilapia, the On-PGRP-SC2 transcripts could be detected in all the examined tissues, with the most abundant expression in the muscle. When infected with S. agalactiae, there was a clear time-dependent expression pattern of On-PGRP-SC2 in the spleen, head kidney and brain. The assays for the amidase activity suggested that recombinant On-PGRP-SC2 protein had a Zn(2+)-dependent PGN-degrading activity. Moreover, our works showed that recombinant On-PGRP-SC2 protein could significantly reduce bacterial load in target organs attacked by S. agalactiae. These findings indicated that On-PGRP-SC2 may play important roles in the immune response to S. agalactiae in Nile tilapia.

  18. Acid-base chemistry in the formation of Mackay-type icosahedral clusters: μ3-acidity analysis of Sc-rich phases of the Sc-Ir system.

    Science.gov (United States)

    Guo, Yiming; Stacey, Timothy E; Fredrickson, Daniel C

    2014-05-19

    The crystal structures of intermetallic phases offer a wealth of geometrical features (helices, multishelled clusters, and host-guest motifs) whose formation has yet to be explained or predicted by chemical theory. A recently developed extension of the acid-base concept to metallic systems, the μ3-acidity model, provides an avenue for developing this understanding for intermetallics formed from transition metals. In this Article, we illustrate how this approach can be used to understand one of the most striking geometrical entities to emerge in intermetallic chemistry, the Mackay cluster of icosahedral quasicrystals. We present μ3-acidity analyses, based on DFT-calibrated Hückel calculations, for a series of Sc-Ir intermetallics: ScIr (CsCl-type), Sc2Ir (Ti2Ni-type), Sc11Ir4, and the Mackay cluster containing phases Sc57Ir13 and Sc44Ir7. We begin by illustrating that a μ3-acidity model correctly predicts that each of these phases is stable relative to disproportionation into their neighboring compounds when a common set of Hückel parameters and d-orbital occupancies is used. Next, we explain these results by developing a relationship between the distance distribution of homoatomic contacts within an atom's coordination sphere and the μ3-neutralization it experiences. For a given average homoatomic distance, the role of heteroatomic contacts is higher when the distribution of homoatomic contacts is narrower. This effect is key to the strength of the acid-base neutralization of the Sc-rich phases, where the Sc atoms find a scarcity of Ir atoms from which to obtain neutralization. Under these circumstances, Sc-Ir contacts should be maximized, whereas the number and distance variations of the Sc-Sc contacts should be minimized. These expectations are borne out by the observed crystal structures. In particular, the Mackay clusters of Sc57Ir13 and Sc44Ir7, in which a central Ir atom is icosahedrally coordinated by a pentagonal dodecahedral array of face-sharing Sc

  19. Effect of ScAl/sub 3/ phase dispersity on hardening of Al-6. 3 pct Mg-0. 21 pct Sc alloy

    Energy Technology Data Exchange (ETDEWEB)

    Drits, M.E.; Bykov, IU.G.; Toropova, L.S.

    1985-09-01

    The relative contributions of disperse coherent ScAl/sub 3/ segregations and of the substructure to the hardening of an aluminum alloy containing 6.3 pct Mg and 0.21 pct Sc are evaluated quantitatively. It is shown that the extent of substructure hardening is independent of the dispersity of coherent ScAl/sub 3/ particles and, consequently, of the homogenizing treatment. The contribution of coherent ScAl/sub 3/ segregations less than 20 nm in diameter to the hardening of the alloy significantly exceeds that of substructure hardening. 9 references.

  20. Superior oblique surgery: when and how?

    Directory of Open Access Journals (Sweden)

    Taylan Şekeroğlu H

    2013-08-01

    Full Text Available Hande Taylan Şekeroğlu,1 Ali Sefik Sanac,1 Umut Arslan,2 Emin Cumhur Sener11Department of Ophthalmology, 2Department of Biostatistics, Hacettepe University Faculty of Medicine, Ankara, TurkeyBackground: The purpose of this paper is to review different types of superior oblique muscle surgeries, to describe the main areas in clinical practice where superior oblique surgery is required or preferred, and to discuss the preferred types of superior oblique surgery with respect to their clinical outcomes.Methods: A consecutive nonrandomized retrospective series of patients who had undergone superior oblique muscle surgery as a single procedure were enrolled in the study. The diagnosis, clinical features, preoperative and postoperative vertical deviations in primary position, type of surgery, complications, and clinical outcomes were reviewed. The primary outcome measures were the type of strabismus and the type of superior oblique muscle surgery. The secondary outcome measure was the results of the surgeries.Results: The review identified 40 (20 male, 20 female patients with a median age of 6 (2–45 years. Nineteen patients (47.5% had Brown syndrome, eleven (27.5% had fourth nerve palsy, and ten (25.0% had horizontal deviations with A pattern. The most commonly performed surgery was superior oblique tenotomy in 29 (72.5% patients followed by superior oblique tuck in eleven (27.5% patients. The amount of vertical deviation in the fourth nerve palsy and Brown syndrome groups (P = 0.01 for both and the amount of A pattern in the A pattern group were significantly reduced postoperatively (P = 0.02.Conclusion: Surgery for the superior oblique muscle requires experience and appropriate preoperative evaluation in view of its challenging nature. The main indications are Brown syndrome, fourth nerve palsy, and A pattern deviations. Superior oblique surgery may be effective in terms of pattern collapse and correction of vertical deviations in primary

  1. Al-Mg-Sc-Zr合金的再结晶%Recrystallization of Al-Mg-Sc-Zr Alloys

    Institute of Scientific and Technical Information of China (English)

    张永红; 尹志民; 张杰; 潘青林; 彭志辉

    2002-01-01

    研究了添加微量Sc,Zr的Al-Mg合金的再结晶行为,结果表明:Al-Mg-Sc-Zr合金的再结晶起始温度为400℃,细小、弥散、与基体共格的析出相对位错和亚晶的钉扎作用是合金再结晶温度大幅度提高的主要原因,再结晶形核机制为亚晶聚合机制.%The recrystalization behavior of Al-Mg alloys with Sc and Zr additives was studied.It is found that the recrystallization of the alloy began at 400℃.The main reason of the great increase of recrystallization temperature is attributed to that the dislocations and subgrain boundaries.The recrystallizing nucleation mechanism was the subgrain boundary merging mechanism in the alloy are pinned by ultrafine dispersed coherent precipitates.

  2. Fourier Transform Microwave Spectroscopy of Sc13C2 and Sc12C13C: Establishing AN Accurate Structure of ScC2 (tilde{X}2A1)

    Science.gov (United States)

    Burton, Mark; Halfen, DeWayne T.; Min, Jie; Ziurys, Lucy M.

    2016-06-01

    Pure rotational spectra of Sc13C2 and Sc12C13C (tilde{X}2A1) have been obtained using Fourier Transform Microwave methods. These molecules were created from scandium vapor in combination with 13CH4 and/or 12CH4, diluted in argon, using a Discharge Assisted Laser Ablation Source (DALAS). Transitions in the frequency range of 14-30 GHz were observed for both species including hyperfine splitting due to the nuclear spin of Sc (I = 7/2) and 13C (I = 1/2). Rotational, spin-rotational, and hyperfine constants have been determined for Sc13C2 and Sc12C13C, as well as a refined structure for ScC2. In agreement with theoretical calculations and previous Sc12C2 results, these data confirm a cyclic (or T-shaped) structure for this molecule. Scandium carbides have been shown to form endohedral-doped fullerenes, which have unique electrical and magnetic properties due to electron transfer between the metal and the carbon-cage. Spectroscopy of ScC2 provides data on model systems for comparison with theory.

  3. Analysis of the effects of application of PST and SC on the performance of the UCPTE system in the Balkans

    Energy Technology Data Exchange (ETDEWEB)

    Papazoglou, T.M. [Technological Educational Inst., Iraklio (Greece); Popovic, D.P.; Mijailovic, S. [Nikola Tesla Inst., Belgrade (Yugoslavia)

    1995-11-01

    Comparison is made of the effectiveness on the steady state load flow control of the Phase Shifter and the Series Compensation. Attention is focused on the ability to reduce unscheduled loop flows and redirect power flows in the system. The Balkan section of UCPTE system resulting after the parallel synchronous interconnection of Bulgaria is used as test system with loading conditions corresponding to the 1995 peak load. The superior properties of PST on power flow control are shown. The positive effects of PST in maintaining a high level of steady state security while realizing relatively large multilateral power exchange programs are demonstrated. A comparison of the power flow control efficiencies and an economic estimate are made for PST and SC. 10 refs, 1 fig, 4 tabs

  4. Performance Analysis of OFDM 60GHz System and SC-FDE 60GHz System

    Directory of Open Access Journals (Sweden)

    Han Xueyan

    2016-01-01

    Full Text Available In this paper, the performance of 60GHz wireless communication system with SC and OFDM is studied, the models of OFDM 60GHz system and SC 60GHz frequency domain equalization (SC-FDE system are established, and the bit error rate (BER performance of OFDM 60GHz system and SC-FDE 60GHz system in 802.15.3c channels is compared. The simulation results show that SC-FDE 60GHz system has a slight advantage over OFDM system in line-of-sight (LOS channels, while OFDM 60GHz system has a slight advantage over SC-FDE system in non-line-of-sight (NLOS channels. For 60GHz system, OFDM 60GHz system has a slight advantage over SC-FDE system in overcoming multipath fading, but the performance of both is close whether in the LOS or NLOS case.

  5. Superior-subordinate relations as organizational processes

    DEFF Research Database (Denmark)

    Asmuss, Birte; Aggerholm, Helle Kryger; Oshima, Sae

    Since the emergence of the practice turn in social sciences (Golsorkhi et al. 2010), studies have shown a number of institutionally relevant aspects as achievements across time and by means of various resources (human and non-human) (Taylor & van Every 2000, Cooren et al. 2006). Such a process view...... on organizational practices relates closely to an increased focus on communication as being constitutive of the organization in general and the superior-subordinate relationship in specific. The current study aims to contribute to this line of research by investigating micro-practices involved in establishing...... superior-subordinate relations in a specific institutionalized setting: performance appraisal interviews (PAIs). While one main task of PAIs is to manage and integrate organizational and employee performance (Fletcher, 2001:473), PAIs are also organizational practices where superior-subordinate relations...

  6. Lake Superior Aquatic Invasive Species Complete Prevention Plan

    Science.gov (United States)

    The Lake Superior Aquatic Invasive Species Complete Prevention Plan is an expression of the best professional judgment of the members of the Lake Superior Task Force as to what is necessary to protect Lake Superior from new aquatic invasive species.

  7. Endovascular treatment of superior vena cava syndrome

    DEFF Research Database (Denmark)

    Duvnjak, Stevo; Andersen, Poul Erik

    2011-01-01

    Abstract AIM: The aim of this study was to report our experience with palliative stent treatment of superior vena cava syndrome. METHODS: Between January 2008 and December 2009, 30 patients (mean age 60.7 years) were treated with stents because of stenosed superior vena cava. All patients presented...... there was an immediate clinical improvement with considerable reduction in the edema of upper extremities and head. There was, however, continous dyspnea in five patients (17%) and two patients (7%) had persistent visible collateral venous circulations on the upper chest. There were no stent associated complications...

  8. Post-elution processing of {sup 44}Ti/{sup 44}Sc generator-derived {sup 44}Sc for clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Pruszynski, M. [Institute of Nuclear Chemistry and Technology, 03-195 Warszawa (Poland); Loktionova, N.S. [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, D-55128 Mainz (Germany); Filosofov, D.V. [Joint Institute of Nuclear Research, DLNP, 141980 Dubna (Russian Federation); Roesch, F., E-mail: frank.roesch@uni-mainz.d [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, D-55128 Mainz (Germany)

    2010-09-15

    The {sup 44}Ti/{sup 44}Sc (T{sub 1/2}{sup 44}Ti=60 a) generator provides cyclotron-independent access to positron-emitting {sup 44}Sc (T{sub 1/2}=3.97 d) for PET imaging. This work aims to post-elution processing of initial {sup 44}Sc generator eluates in order to reduce its volume, HCl concentration and remove the oxalate anions. The on-line adsorption of {sup 44}Sc on cationic resin AG 50W-X8 (200-400 mesh, H{sup +}-form) is achieved with >98% efficacy. Subsequently, the purified {sup 44}Sc is desorbed by using 3 ml of 0.25 M ammonium acetate (pH=4.0). The post-processing takes 10 min. The overall yield of the post-processing reached 90%, which is referred to the {sup 44}Sc obtained from the {sup 44}Ti/{sup 44}Sc generator. In addition to the chemical purification, the content of {sup 44}Ti breakthrough was further reduced by one order of magnitude. The 185 MBq generator finally provides 150 MBq of {sup 44}Sc containing <10 Bq of {sup 44}Ti ready for labeling.

  9. Heterogeneity of abnormal prion protein (PrP(Sc)) in murine scrapie prions determined by PrP(Sc)-specific monoclonal antibodies.

    Science.gov (United States)

    Ushiki-Kaku, Yuko; Shimizu, Yoshihisa; Tabeta, Naoko; Iwamaru, Yoshifumi; Ogawa-Goto, Kiyoko; Hattori, Shunji; Yokoyama, Takashi

    2014-03-01

    In prion diseases, abnormal prion protein (PrP(Sc)) is considered as the main component of the infectious agent. Delineation of PrP(Sc) conformation is expected to be a critical factor in understanding properties of prions. However, practical methods to differentiate between conformers of PrP(Sc) are inadequate. Here, we used two PrP(Sc)-specific monoclonal antibodies (mAbs), 3B7 and 3H6, and found that mAb 3H6 detected a limited portion of PrP(Sc) in five mice-adapted prion strains. The quantity of mAb 3H6-precipitated PrP(Sc) was significantly lesser in 22L compared to other strains. This result provides a direct evidence of the conformational heterogeneity of PrP(Sc) within the prion strains. Conformation-specific probes, like these mAbs, have the potential to be powerful tools for investigating conformational variations in PrP(Sc).

  10. THE SC7/SC14 GENE FAMILY OF SCHIZOPHYLLUM-COMMUNE CODES FOR EXTRACELLULAR PROTEINS SPECIFICALLY EXPRESSED DURING FRUIT-BODY FORMATION

    NARCIS (Netherlands)

    SCHUREN, FHJ; ASGEIRSDOTTIR, SA; KOTHE, EM; SCHEER, JMJ; WESSELS, JGH

    The Sc7 and Sc14 genes are specifically expressed in the dikaryon of the basidiomycete fungus Schizophyllum commune during fruiting. These genes are closely linked (within 6 kb) and highly similar in gene structure and nucleotide sequence (70% identical nucleotides in their coding regions). The

  11. Collicular dysfunction in attention deficit hyperactivity disorder.

    Science.gov (United States)

    Overton, Paul G

    2008-01-01

    Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder characterised by (inter alia) an increase in distractibility. The current front-line pharmacotherapies for the treatment of ADHD, namely the psychostimulants methylphenidate and amphetamines, have clear abuse potential, hence there is a strong need to develop new drug treatments for this disorder. Central to this process is the identification of the pathophysiological changes which underlie ADHD. Given the heterogeneity of the disorder, multiple loci are probably involved, providing multiple potential therapeutic targets. Here, we hypothesise (Hypothesis 1) that one such locus is the superior colliculus (SC), a sensory structure intimately linked with distractibility and the production of eye and head movements. It is proposed that in ADHD, the colliculus is hyper-responsive, leading to the core symptom of increased distractibility. Hypothesis 1 is supported by: 1. ADHD patients show increased distractibility in tasks which are sensitive to collicular function; 2. ADHD patients have a general problem inhibiting saccades, the generation of which involves the SC; 3. Saccadic deficits in ADHD include defects in the production of saccadic types (anti-saccades and express saccades) which are particularly associated with the colliculus; 4. Covert shifts in attention (which also have been argued to involve the SC) are also impaired in ADHD; 5. Reading disorders are frequently co-morbid with ADHD; dyslexia (which is associated with eye movement problems) is linked to a specific visual perceptual deficit in the M pathway, a major recipient of which is the colliculus. Whether or not the SC is indeed hyper-responsive in ADHD as Hypothesis 1 suggests, the SC may well represent an important therapeutic target for drugs. In fact current psychostimulant therapies, which reduce distractibility, may already work at that level (Hypothesis 2), a contention which is supported by: 1. The

  12. Magnetic resonance imaging evaluation of meniscoid superior labrum: normal variant or superior labral tear*

    Science.gov (United States)

    Simão, Marcelo Novelino; Vinson, Emily N.; Spritzer, Charles E.

    2016-01-01

    Objective The objective of this study was to determine the incidence of a "meniscoid" superior labrum. Materials and Methods This was a retrospective analysis of 582 magnetic resonance imaging examinations of shoulders. Of those 582 examinations, 110 were excluded, for a variety of reasons, and the final analysis therefore included 472 cases. Consensus readings were performed by three musculoskeletal radiologists using specific criteria to diagnose meniscoid labra. Results A meniscoid superior labrum was identified in 48 (10.2%) of the 472 cases evaluated. Arthroscopic proof was available in 21 cases (43.8%). In 10 (47.6%) of those 21 cases, the operative report did not include the mention a superior labral tear, thus suggesting the presence of a meniscoid labrum. In only one of those cases were there specific comments about a mobile superior labrum (i.e., meniscoid labrum). In the remaining 11 (52.4%), surgical correlation demonstrated superior labral tears. Conclusion A meniscoid superior labrum is not an infrequent finding. Depending upon assumptions and the requirement of surgical proof, the prevalence of a meniscoid superior labrum in this study was between 2.1% (surgically proven) and 4.8% (projected). However, superior labral tears are just as common and are often confused with meniscoid labra. PMID:27777474

  13. Structural transformations in Sc/Si multilayers irradiated by EUVlasers

    Energy Technology Data Exchange (ETDEWEB)

    Voronov, D.L.; Zubarev, E.N.; Pershyn, Y.P.; Sevryukova, V.A.; Kondratenko, V.V.; Vinogradov, A.V.; Artioukov, I.A.; Uspenskiy, Y.A.; Grisham, M.; Vaschenko, G.; Menoni, C.S.; Rocca, J.J.

    2007-08-21

    Multilayer mirrors for the extreme ultraviolet (EUV) are keyelements for numerous applications of coherent EUV sources such as newtabletop lasers and free-electron lasers. However the field ofapplications is limited by the radiation and thermal stability of themultilayers. Taking into account the growing power of EUV sources thestability of the optics becomes crucial. To overcome this problem it isnecessary to study the degradation of multilayers and try to increasetheir temporal and thermal stability. In this paper we report the resultsof detailed study of structural changes in Sc/Simultilayers when exposedto intense EUV laser pulses. Various types of surface damage such asmelting, boiling, shockwave creation and ablation were observed asirradiation fluencies increase. Cross-sectional TEM study revealed thatthe layer structure was completely destroyed in the upper part ofmultilayer, but still survived below. The layers adjacent tothe substrateremained intact even through the multilayer surface melted down, thoughthe structure of the layers beneath the molten zone was noticeablychanged. The layer structure in this thermally affected zone is similarto that of isothermally annealed samples. All stages of scandium silicideformation such as interdiffusion, solid-state amorphization, silicidecrystallization, etc., are present in the thermally affected zone. Itindicates a thermal nature of the damage mechanism. The tungstendiffusion barriers were applied to the scandium/silicon interfaces. Itwas shown that the barriers inhibited interdiffusion and increased thethermal stability of Sc/Si mirrors.

  14. V-ATPase, ScNhxlp and Yeast Vacuole Fusion

    Institute of Scientific and Technical Information of China (English)

    Quan-Sheng Qiu

    2012-01-01

    Membrane fusion is the last step in trafficking pathways during which membrane vesicles fuse with target organelles to deliver cargos.It is a central cellular reaction that plays important roles in signal transduction,protein sorting and subcellular compartmentation.Recent progress in understanding the roles of ion transporters in vacuole fusion in yeast is summanzed in this article.It is becoming increasingly evident that the vacuolar proton pump V-ATPase and vacuolar Na+/H+ antiporter ScNhxlp are key components of the vacuole fusion machinery in yeast.Yeast ScNhxlp regulates vacuole fusion by controlling the luminal pH.V-ATPases serve a dual role in vacuolar integrity in which they regulate both vacuole fusion and fission reactions in yeast.Fission defects are epistatic to fusion defects.Vacuole fission depends on the proton translocation activity of the V-ATPase; by contrast,the fusion reaction does not need the transport activity but requires the physical presence of the proton pump.Vo,the membrane-integral sector of the V-ATPase,forms trans-complexes between the opposing vacuoles in the terminal phase of vacuole fusion where the Vo trans-complexes build a continuous proteolipid channel at the fusion site to mediate the bilayer fusion.

  15. The first SC-SAGD pilot in the Grosmont

    Energy Technology Data Exchange (ETDEWEB)

    Solanki, S.C.; Barrett, K.; Riva, D.; Becker, L.; Brindle, G. [Laricina Energy Ltd. (Canada)

    2011-07-01

    In north-eastern Alberta, the Grosmont Formation is an Upper Devonian carbonate succession containing a vast amount of bitumen. In an attempt to exploit this resource, Laricina Energy Ltd. and OSUM Oil Sands Corp. built the first ever solvent-cyclic steam-assisted gravity drainage (SC-SAGD) pilot. In this process, solvent and/or steam are continuously injected at reservoir pressure to heat the reservoir and thus reduce bitumen viscosity. The aim of this paper is to present the pilot project and its initial results. The reservoir's geology, the recovery process, the drilling and completion challenges as well as the design and the operational plan are discussed in this paper. Steam injection started in December 2010 and indications show that the wells are progressing as planned. Results showed an uptime greater than 90% so far and this is expected to further improve in the future. The first SC-SAGD pilot is discussed and early phases showed excellent results from the project.

  16. A first-principles study of hydrogen interaction and saturation on ScAl{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Samolia, Madhu [Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar 140001 (India); Dhilip Kumar, T.J., E-mail: dhilip@iitrpr.ac.in [Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar 140001 (India)

    2013-03-05

    Graphical abstract: Electrostatic potential superimposed on electron density of H{sub 2}, Al{sub 4} and ScAI{sub 3}. Highlights: ► A first principles calculation on hydrogen interaction and saturation on stable ScAl{sub 3} cluster is performed. ► Sc atom has higher negative charge electron density over Al atom in ScAl{sub 3} from natural bond orbital charge analysis. ► H{sub 2} undergoes dissociative chemisorption on the Sc atop site resulting in Sc–H–AI bridge bond. ► H{sub 2} saturation on Sc site results initially in chemisorption and then physisorption with the maximum loading of 6 molecules resulting in stable ScAl{sub 3}H{sub 12} structure. -- Abstract: Complex metal hydrides are promising hydrogen storage material for mobile applications. The presence of scandium catalysts in complex metal hydrides is found to improve significantly the kinetics of H{sub 2} adsorption and desorption. The exact role of these additives is not completely understood. NMR studies suggests the presence of distorted ScAl{sub 3} phase which is attributed to the enhancement of reversible uptake and release rates of H{sub 2}. In this study, we have investigated the hydrogen interaction and saturation on stable ScAl{sub 3} cluster at various sites using the density functional theory by employing unrestricted B3LYP/6-311++G(d,p) and the GGA-PW91/DNP methods. From natural bond orbital charge analysis and electrostatic potential superimposed on electron density plots, ScAl{sub 3} is found to be more polarized and Sc atom in ScAl{sub 3} cluster has higher negative charge and electron density over Al atoms. H{sub 2} undergoes dissociative chemisorption on the Sc atop site in ScAl{sub 3} resulting in Sc–H–Al bridge structure. The hydrogen saturation is studied by sequential H{sub 2} adsorption on ScAl{sub 3} cluster. In the Sc site, the first H{sub 2} molecule undergoes dissociative chemisorption and further addition results in H{sub 2} physisorption with the maximum loading

  17. Directed evolution of human scFvs in DT40 cells.

    Science.gov (United States)

    Lim, Alfred W Y; Williams, Gareth T; Rada, Cristina; Sale, Julian E

    2016-02-01

    Cells that constitutively diversify their immunoglobulin genes can be used for selection of novel antibodies and for refining existing affinities and specificities. Here, we report an adaptation of the chicken DT40 system wherein its capacity for somatic hypermutation is harnessed to evolve human antibodies expressed as single-chain variable fragments (scFvs). Expression of membrane-anchored scFvs from within the rearranged Igλ locus created self-diversifying scFv libraries from which we could both select scFvs of a desired specificity and evolve both the specificity and affinity of existing scFvs by iterative expansion and selection. From these scFvs, we were able to create fully human IgG antibodies with nanomolar affinities. We further enhanced the functionality of the system by creating a pool of DT40 scFv lines with high levels of mutation driven by the overexpression of a hyperactive variant of activation-induced deaminase. From this library, we successfully isolated scFvs that bound the spliceosome factor CWC15 and the cytokine human IFNγ. Our results demonstrate the flexibility and utility of DT40 for rapid generation of scFv repertoires and efficient selection, evolution and affinity maturation of scFv specificities.

  18. Effects of salicylate on dopamine levels in rat inferior colliculus%水杨酸钠对大鼠下丘多巴胺水平影响的研究

    Institute of Scientific and Technical Information of China (English)

    刘俊秀; 刘轶君; 毛兰群; 李学佩; 马芙蓉

    2016-01-01

    Objective To investigate dopamine level changes in the inferior colliculus induced by salicylate and the role of dopamine in the mechanisms of tinnitus. Methods In an animal model of salicylate-induced tinnitus, we employed microdialysis combined with electrochemical methodologies to monitor changes of dopamine in rat inferior colliculus. Re-sults Salicylate produced significant decrease in dopamine levels in the inferior colliculus, to a minimum of 49 ± 9%of base-line around 3 h post injection, followed by a return to the baseline by the end of the fifth hour. In contrast, saline did not pro-duce any clear changes. Conclusion The decrease of dopamine in the inferior colliculus may be involved in the generation of tinnitus. Our in vivo data provide direct evidence of the important roles the dopaminergic system plays in the generation of tinnitus.%目的:探讨听觉中枢核团下丘内多巴胺水平的变化在耳鸣发病机制中的作用。方法在水杨酸钠诱导建立的耳鸣动物模型基础上,利用微透析技术结合高效液相电化学检测方法,活体、动态研究水杨酸钠作用后大鼠下丘内多巴胺水平的变化。结果水杨酸钠引起大鼠下丘多巴胺水平显著性地降低。大约3小时后下丘内多巴胺水平降至最低,达到基础值的49±9%,然后缓慢的升高,大约5小时后恢复到基线水平。生理盐水对照组未引起任何明显的变化。结论大鼠下丘内多巴胺水平的显著性降低可能与水杨酸钠诱导的耳鸣产生有关,这些活体数据为多巴胺这一调节人们精神活动的重要递质参与耳鸣的发生提供直接的实验证据。

  19. Distinct effects of haloperidol in the mediation of conditioned fear in the mesolimbic system and processing of unconditioned aversive information in the inferior colliculus.

    Science.gov (United States)

    Muthuraju, S; Nobre, M J; Saito, V M N; Brandao, M L

    2014-03-07

    Chemical and electrical stimulation of the inferior colliculus (IC) causes defensive behavior. Electrical stimulation of the IC at the escape threshold enhances dopamine (DA) release in the prefrontal cortex. Intra-ventral tegmental area injections of quinpirole at doses that act presynaptically reduce the release of DA in the terminal fields of the mesolimbic system and clearly reduce conditioned fear in several animal models of anxiety. However, little is known about the involvement of DA in the mediation of unconditioned fear, such as the reactivity to acute stressors. The present study investigated the neural substrates mediated by DA transmission associated with emotional changes triggered by the activation or inhibition of D2 receptors during conditioned and unconditioned fear. We examined the effects of systemic or local injections of the DA-receptor antagonist and agonist haloperidol and quinpirole, respectively, into the IC in rats subjected to fear-potentiated startle, a Pavlovian paradigm that uses loud sounds as the unconditioned stimulus and light previously paired with footshock as the conditioned stimulus. We also assessed auditory-evoked potentials (AEPs) recorded from electrodes implanted in the IC. Intraperitoneal haloperidol administration dose-dependently enhanced AEPs induced by loud tones and inhibited fear-potentiated startle. Intra-IC injections of quinpirole left AEPs unchanged, suggesting that an optimal level of postsynaptic D2 receptors in the IC may regulate the transmission of aversive information through the midbrain tectum. These findings provide evidence of opposing DA-mediated mechanisms in fear/anxiety processes that depend on the area under study. The activity of the neural substrates of conditioned fear was attenuated by haloperidol, whereas midbrain neural substrates of unconditioned fear were enhanced. Thus, DA appears to regulate unconditioned fear at the midbrain level, likely by reducing the sensory gating of aversive

  20. Increased responsiveness and failure of habituation in neurons of the external nucleus of inferior colliculus associated with audiogenic seizures of the genetically epilepsy-prone rat.

    Science.gov (United States)

    Chakravarty, D N; Faingold, C L

    1996-10-01

    Initiation of audiogenic seizures (AGS) emanates from the inferior colliculus (IC) to other IC subnuclei in the genetically epilepsy-prone rat (GEPR). The external nucleus of IC (ICx) is a suggested site of convergence of the auditory output onto the sensorimotor integration network components for AGS in the brainstem. Neuronal firing was recorded from the ICx of the awake, freely moving GEPR and normal Sprague-Dawley rats using microwire electrodes in the present study. Auditory stimuli consisted of 12-kHz tones (100 ms, 5-ms rise-fall at rates of 1/4s, 1/2s, and 1/s). AGS incidence in the GEPR is highest at 12 kHz. In the GEPR, ICx neuronal responses to acoustic stimuli were significantly greater than those seen in normal rats. This increased ICx firing was observed at relatively high acoustic intensities (> 80 dB SPL), which are near the threshold for AGS induction. Repetition-induced response attenuation (habituation) is commonly observed in ICx neurons, which appears to be overcome in the GEPR during AGS initiation. Tonic, acoustically evoked ICx neuronal firing was observed just prior to wild running. ICx firing was suppressed during the tonic and postictal phases of AGS. Recovery of ICx responses occurred when the animal regained postural control. Abnormal, intense output has previously been observed in the GEPR IC central nucleus (ICc) neurons. The neuronal firing pattern changes observed in the ICx in the present study may result from this intense ICc output. Diminished efficacy of GABA, which has been observed in several regions of the GEPR brain, including the IC, in a number of previous studies, may be involved in the exaggerated ICx responses to acoustic stimuli in the GEPR. Participation of the ICx in the AGS neuronal network may be subserved by this acoustic hyperresponsiveness.

  1. Impact of response duration on multisensory integration

    OpenAIRE

    Ghose, Dipanwita; Zachary P Barnett; Wallace, Mark T.

    2012-01-01

    Multisensory neurons in the superior colliculus (SC) have been shown to have large receptive fields that are heterogeneous in nature. These neurons have the capacity to integrate their different sensory inputs, a process that has been shown to depend on the physical characteristics of the stimuli that are combined (i.e., spatial and temporal relationship and relative effectiveness). Recent work has highlighted the interdependence of these factors in driving multisensory integration, adding a ...

  2. Effect of Severe Plastic Deformation on Structure and Properties of Al-Sc-Ta and Al-Sc-Ti Alloys.

    Science.gov (United States)

    Berezina, Alla; Monastyrska, Tetiana; Davydenko, Olexandr; Molebny, Oleh; Polishchuk, Sergey

    2017-12-01

    The comparative analysis of the effect of monotonous and non-monotonous severe plastic deformations (SPD) on the structure and properties of aluminum alloys has been carried out. Conventional hydrostatic extrusion (HE) with a constant deformation direction and equal-channel angular hydroextrusion (ECAH) with an abrupt change in the deformation direction were chosen for the cases of monotonous and non-monotonous SPD, respectively. Model cast hypoeutectic Al-0.3%Sc alloys and hypereutectic Al-0.6%Sc alloys with Ta and Ti additives were chosen for studying. It was demonstrated that SPD of the alloys resulted in the segregation of the material into active and inactive zones which formed a banded structure. The active zones were shown to be bands of localized plastic deformation. The distance between zones was found to be independent of the accumulated strain degree and was in the range of 0.6-1 μm. Dynamic recrystallization in the active zones was observed using TEM. The dynamic recrystallization was accompanied by the formation of disclinations, deformation bands, low-angle, and high-angle boundaries, i.e., rotational deformation modes developed. The dynamic recrystallization was more intense during the non-monotonous deformation as compared with the monotonous one, which was confirmed by the reduction of texture degree in the materials after ECAH.

  3. SC1327-312 & SC1329-313 two galaxy groups in-between a major merging event observed with Beppo-SAX

    CERN Document Server

    Bardelli, S; Ettori, S; Molendi, S; Zucca, E; Colafrancesco, Sergio

    2001-01-01

    We present the results of two Beppo-SAX observations of the poor clusters SC1327-312 and SC1329-313. These objects are located in a huge structure, formed by three ACO clusters, which is probably the remnant of one of the largest and best studied major mergings known. Given the fact that these poor clusters are in between two interacting ACO clusters, the aim of this work is to study the physics of the intracluster medium and to look for the possible presence of shocks. We derived the gas distribution profiles, the global (i.e. within 0.3 Mpc) temperatures and abundances and the temperature profiles and maps for SC1327-312 and SC1329-313. Also the presence of soft excess in LECS and hard excess in PDS have been checked. We do not find evidence of regions where the gas is shocked or significantly heated. The image of SC1327-312 seems rather symmetric, while the gas profile of SC1329-313 shows disturbed, comet-like shaped isophotes, with the tail pointing toward A3562 and a compression toward SC1327-312. The pr...

  4. Preparation and characterization of Sc doped MgB2 wires

    Science.gov (United States)

    Grivel, J.-C.; Burdusel, M.

    2016-09-01

    The in-situ technique was used to manufacture scandium (Sc) doped MgB2 wires in a composite Cu-Nb sheath. After reaction at 700 °C, at most 1 at.% Mg was replaced by Sc in the MgB2 phase, without significant influence on its superconducting transition temperature. For higher Sc concentrations in the nominal composition, the formation of Sc-rich impurity phases was evidenced by SEM/EDS observations. The critical current density and accommodation field of the wires are weakly dependant on the Sc content. It is believed that these effects are related more to modifications of the thermal behaviour of the precursor powders revealed by DTA measurements than to actual doping. The best performance was obtained in a wire with Mg:Sc = 0.995_0.005 atomic ratio.

  5. In vitro neutralization of prions with PrP(Sc)-specific antibodies.

    Science.gov (United States)

    Taschuk, Ryan; Van der Merwe, Jacques; Marciniuk, Kristen; Potter, Andrew; Cashman, Neil; Griebel, Philip; Napper, Scott

    2015-01-01

    Prion diseases reflect the misfolding of a self-protein (PrP(C)) into an infectious, pathological isomer (PrP(Sc)). By targeting epitopes uniquely exposed by misfolding, our group developed PrP(Sc)-specific vaccines to 3 disease specific epitopes (DSEs). Here, antibodies induced by individual DSE vaccines are evaluated for their capacity to neutralize prions in vitro. For both purified antibodies and immunoreactive sera, the PrP(Sc)-specific antibodies were equally effective in neutralizing prions. Further, there was no significant increase in neutralizing activity when multiple DSEs were targeted within an assay. At a low antibody concentration, the PrP(Sc)-specific antibodies matched the neutralization achieved by an antibody that may act via both PrP(C) and PrP(Sc). At higher doses, however, this pan-specific antibody was more effective, potentially due to a combined deactivation of PrP(Sc) and depletion of PrP(C).

  6. Sulfated dextrans enhance in vitro amplification of bovine spongiform encephalopathy PrP(Sc and enable ultrasensitive detection of bovine PrP(Sc.

    Directory of Open Access Journals (Sweden)

    Yuichi Murayama

    Full Text Available BACKGROUND: Prions, infectious agents associated with prion diseases such as Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE in cattle, and scrapie in sheep and goats, are primarily comprised of PrP(Sc, a protease-resistant misfolded isoform of the cellular prion protein PrP(C. Protein misfolding cyclic amplification (PMCA is a highly sensitive technique used to detect minute amounts of scrapie PrP(Sc. However, the current PMCA technique has been unsuccessful in achieving good amplification in cattle. The detailed distribution of PrP(Sc in BSE-affected cattle therefore remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: We report here that PrP(Sc derived from BSE-affected cattle can be amplified ultra-efficiently by PMCA in the presence of sulfated dextran compounds. This method is capable of amplifying very small amounts of PrP(Sc from the saliva, palatine tonsils, lymph nodes, ileocecal region, and muscular tissues of BSE-affected cattle. Individual differences in the distribution of PrP(Sc in spleen and cerebrospinal fluid samples were observed in terminal-stage animals. However, the presence of PrP(Sc in blood was not substantiated in the BSE-affected cattle examined. CONCLUSIONS/SIGNIFICANCE: The distribution of PrP(Sc is not restricted to the nervous system and can spread to peripheral tissues in the terminal disease stage. The finding that PrP(Sc could be amplified in the saliva of an asymptomatic animal suggests a potential usefulness of this technique for BSE diagnosis. This highly sensitive method also has other practical applications, including safety evaluation or safety assurance of products and byproducts manufactured from bovine source materials.

  7. Li2S@C composite incorporated into 3D reduced graphene oxide as a cathode material for lithium-sulfur batteries

    Science.gov (United States)

    Wang, D. H.; Xie, D.; Yang, T.; Zhong, Y.; Wang, X. L.; Xia, X. H.; Gu, C. D.; Tu, J. P.

    2016-05-01

    Surface conductive engineering on Li2S is critical for construction of advanced cathodes of lithium-sulfur batteries. Herein, we construct a high-performance Li2S-based composite cathode with the help of three-dimensional reduced graphene oxide (3D-rGO) network and outer carbon coating. Typically, the Li2S@C particles are uniformly embedded into 3D-rGO to form a binder-free 3D-rGO-Li2S@C cathode by the combination of a liquid solution-evaporation coating and PVP (Polyvinyl Pyrrolidone) carbonization. The 3D-rGO-Li2S@C cathode exhibits a high initial discharge capacity of 856 mAh g-1 at 0.1C, superior cycling stability with a capacity of 388.4 mAh g-1 after 200 cycles at 1C, corresponding to a low capacity fading rate. It is demonstrated that the outer conductive coating is effective and necessary for electrochemical enhancement of Li2S cathodes by improving electrical conductivity and prohibiting polysulfide from shuttling during cycling.

  8. Toward low-cost affinity reagents: lyophilized yeast-scFv probes specific for pathogen antigens.

    Directory of Open Access Journals (Sweden)

    Sean A Gray

    Full Text Available The generation of affinity reagents, usually monoclonal antibodies, remains a critical bottleneck in biomedical research and diagnostic test development. Recombinant antibody-like proteins such as scFv have yet to replace traditional monoclonal antibodies in antigen detection applications, in large part because of poor performance of scFv in solution. To address this limitation, we have developed assays that use whole yeast cells expressing scFv on their surfaces (yeast-scFv in place of soluble purified scFv or traditional monoclonal antibodies. In this study, a nonimmune library of human scFv displayed on the surfaces of yeast cells was screened for clones that bind to recombinant cyst proteins of Entamoeba histolytica, an enteric pathogen of humans. Selected yeast-scFv clones were stabilized by lyophilization and used in detection assay formats in which the yeast-scFv served as solid support-bound monoclonal antibodies. Specific binding of antigen to the yeast-scFv was detected by staining with rabbit polyclonal antibodies. In flow cytometry-based assays, lyophilized yeast-scFv reagents retained full binding activity and specificity for their cognate antigens after 4 weeks of storage at room temperature in the absence of desiccants or stabilizers. Because flow cytometry is not available to all potential assay users, an immunofluorescence assay was also developed that detects antigen with similar sensitivity and specificity. Antigen-specific whole-cell yeast-scFv reagents can be selected from nonimmune libraries in 2-3 weeks, produced in vast quantities, and packaged in lyophilized form for extended shelf life. Lyophilized yeast-scFv show promise as low cost, renewable alternatives to monoclonal antibodies for diagnosis and research.

  9. File list: ALL.PSC.50.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.50.AllAg.EpiSC mm9 All antigens Pluripotent stem cell EpiSC SRX535239,SRX53...RX590290,SRX590286,SRX661084,SRX1074905,SRX1074908,SRX535237,SRX535241,SRX661085,SRX1074909,SRX1074906 http://dbarchive.biosc...iencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.50.AllAg.EpiSC.bed ...

  10. File list: ALL.PSC.10.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.10.AllAg.EpiSC mm9 All antigens Pluripotent stem cell EpiSC SRX590288,SRX53...RX590290,SRX1074917,SRX1074916,SRX590285,SRX590286,SRX535242,SRX1074908,SRX1074905,SRX535238,SRX535237 http://dbarchive.biosc...iencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.10.AllAg.EpiSC.bed ...

  11. File list: ALL.PSC.05.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.05.AllAg.EpiSC mm9 All antigens Pluripotent stem cell EpiSC SRX590288,SRX53...RX590290,SRX590289,SRX590285,SRX1074916,SRX1074917,SRX590286,SRX535242,SRX1074908,SRX1074905,SRX535237 http://dbarchive.biosc...iencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.05.AllAg.EpiSC.bed ...

  12. File list: ALL.PSC.20.AllAg.EpiSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.20.AllAg.EpiSC mm9 All antigens Pluripotent stem cell EpiSC SRX535239,SRX66...RX590289,SRX590285,SRX590290,SRX590286,SRX1074909,SRX1074908,SRX1074905,SRX1074906,SRX535237,SRX535241 http://dbarchive.biosc...iencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.20.AllAg.EpiSC.bed ...

  13. DC-SC Photoinjector with Low Emittance at Peking University

    CERN Document Server

    Xiang Rong; Hao, J; Huang, Senlin; Lu Xiang Yang; Quan, Shengwen; Zhang, Baocheng; Zhao, Kui

    2005-01-01

    High average power Free Electron Lasers require the high quality electron beams with the low emittance and the sub-picosecond bunches. The design of DC-SC photoinjector, directly combining a DC photoinjector with an SRF cavity, can produce high average current beam with moderate bunch charge and high duty factor. Because of the DC gun, the emittance increases quickly at the beginning, so a carefully design is needed to control that. In this paper, the simulation of an upgraded design has been done to lower the normalized emittance below 1.5mm·mrad. The photoinjector consists of a DC gap and a 2+1/2-cell SRF cavity, and it is designed to produce 4.2 MeV electron beams at 100pC bunch charge and 81.25MHz repetition rate (8 mA average current).

  14. Domain structure and phase transition in Sc-doped zirconia

    Science.gov (United States)

    Brunauer, G.; Boysen, H.; Frey, F.; Ehrenberg, H.

    2002-01-01

    The temperature dependence of the domain structure associated with the ferroelastic phase transition (Fm↔R bar 3 m) in ZrO2 doped with 11% Sc2O3 has been determined from a peak shape analysis of high-resolution synchrotron x-ray powder diffraction data. In the temperature region of coexisting phases the observed characteristic anisotropic broadening and asymmetry of the lines is modelled by three different phases: a main rhombohedral phase, a distorted rhombohedral phase with a smaller c/a ratio, and a cubic phase. The latter two are assigned to the internal structure of the domain walls between two adjacent twin domains. The size and amount of the cubic phase show an initially slow increase with temperature followed by a very steep increase and a slow one after that. The size of the (main) rhombohedral domains remains nearly constant, while (micro-) strain in the distorted regions gradually decreases.

  15. M.Sc. in Civil and Structural Engineering

    DEFF Research Database (Denmark)

    Clausen, Johan Christian

    The following pages contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short master projects as well as regular 3rd...... semester projects at the M.Sc. programme in Civil and Structural Engineering. Each project description provides a brief overview of the purpose as well as the main activities. Further, a weighting between theoretical analysis, experimental work and computer modelling has been proposed. Usually...... page. Furthermore, other ideas for projects may be discussed with a potential supervisor. Many private engineering companies have a homepage on which they state that they would like to collaborate with students on a master project....

  16. Final Report for DOE Grant Number DE-SC0001481

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Edison [Rice University

    2013-12-02

    This report covers research activities, major results and publications supported by DE-SC-000-1481. This project was funded by the DOE OFES-NNSA HEDLP program. It was a joint research program between Rice University and the University of Texas at Austin. The physics of relativistic plasmas was investigated in the context of ultra-intense laser irradiation of high-Z solid targets. Laser experiments using the Texas Petawatt Laser were performed in the summers of 2011, 2012 and 2013. Numerical simulations of laser-plasma interactions were performed using Monte Carlo and Particle-in-Cell codes to design and support these experiments. Astrophysical applications of these results were also investigated.

  17. Mean pion multiplicities in Ar+Sc collisions

    CERN Document Server

    Naskręt, Michał

    2016-01-01

    Preliminary results for mean negatively charged pion multiplicities $\\langle \\pi^- \\rangle$ using the $h^-$ method are presented for central Ar+Sc collisions at 13, 19, 30, 40, 75 and 150\\textit{A} GeV/c beam momentum. The data were recorded by the NA61/SHINE detector at the CERN SPS. Starting with rapidity distributions ${dn}/{dy}$ the procedure of obtaining total multiplicities is presented. The mean number of wounded nucleons $\\langle W\\rangle$ extracted from the Glissando MC model is used to calculate the ratio $\\langle \\pi^- \\rangle/\\langle W\\rangle.$ The results are compared to those from other experiments and their dependence on colliding systems and collision energy is discussed.

  18. Superior-subordinate relations as organizational processes

    DEFF Research Database (Denmark)

    Asmuss, Birte; Aggerholm, Helle Kryger; Oshima, Sae

    Since the emergence of the practice turn in social sciences (Golsorkhi et al. 2010), studies have shown a number of institutionally relevant aspects as achievements across time and by means of various resources (human and non-human) (Taylor & van Every 2000, Cooren et al. 2006). Such a process view...... superior-subordinate relations in a specific institutionalized setting: performance appraisal interviews (PAIs). While one main task of PAIs is to manage and integrate organizational and employee performance (Fletcher, 2001:473), PAIs are also organizational practices where superior-subordinate relations...... are shaped, (re)confirmed and re-evaluated. This paper pursues the better understanding of the latter aspect by looking at one substantial and recurrent activity in PAIs: the evaluation of employee performance. One resource for doing the evaluation work is making assessments (e.g. Goodwin & Goodwin, 1987...

  19. Exploring the word superiority effect using TVA

    DEFF Research Database (Denmark)

    Starrfelt, Randi

    Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) has been observed when written stimuli are presented very briefly or degraded by visual noise. It is unclear, however, if this is due to a lower threshold...... for perception of words, or a higher speed of processing for words than letters. We have investigated the WSE using methods based on a Theory of Visual Attention. In an experiment using single stimuli (words or letters) presented centrally, we show that the classical WSE is specifically reflected in perceptual...... processing speed: words are simply processed faster than single letters. It is also clear from this experiment, that the word superiority effect can be observed at a large range of exposure durations, from the perceptual threshold to ceiling performance. Intriguingly, when multiple stimuli are presented...

  20. Resolution of superior oblique myokymia with memantine.

    Science.gov (United States)

    Jain, Saurabh; Farooq, Shegufta J; Gottlob, Irene

    2008-02-01

    We describe a novel treatment of superior oblique myokymia. A 40-year-old woman was treated with gabapentin for this disorder with partial success and reported significant side effects including loss of libido and weight gain. After a drug holiday, memantine therapy was initiated resulting in a substantial improvement in her symptoms with far fewer side effects and stability on long-term maintenance therapy.

  1. Locked Superior Dislocation of the Acromioclavicular Joint

    Directory of Open Access Journals (Sweden)

    Salma Eltoum Elamin

    2013-01-01

    Full Text Available Acromioclavicular (AC joint injuries account for approximately 3–5% of shoulder girdle injuries (Rockwood et al., 1998. Depending on severity of injury and direction of displacement these are classified using Rockwood classification system for AC joint dislocation. We present an unusual case presenting with locked superior dislocation of the AC joint highlighting the presentation and subsequent successful surgical management of such case. To our knowledge this has not been reported previously in literature.

  2. Reperfusion hemorrhage following superior mesenteric artery stenting.

    LENUS (Irish Health Repository)

    Moore, Michael

    2012-02-03

    Percutaneous transluminal angioplasty and stent placement is now an established treatment option for chronic mesenteric ischemia and is associated with low mortality and morbidity rates. We present a case of reperfusion hemorrhage complicating endovascular repair of superior mesenteric artery stenosis. Although a recognized complication following repair of carotid stenosis, hemorrhage has not previously been reported following mesenteric endovascular reperfusion. We describe both spontaneous cessation of bleeding and treatment with coil embolization.

  3. Ferromagnetism carried by highly delocalized hybrid states in Sc-doped ZnO thin films

    KAUST Repository

    Benali Kanoun, Mohammed

    2012-05-29

    We present first-principles results for Sc-doped ZnOthin films. Neighboring Sc atoms in the surface and/or subsurface layers are found to be coupled ferromagnetically, where only two of the possible configurations induce spin polarization. In the first configuration, the polarization is carried by the Sc d states as expected for transition metaldoping. However, there is a second configuration which is energetically favorable. It is governed by polarized hybrid states of the Zns, O p, and Sc d orbitals. Such highly delocalized states can be an important ingredient for understanding the magnetism of dopedZnOthin films.

  4. Atomic bonding and mechanical properties of Al-Mg-Zr-Sc alloy

    Institute of Scientific and Technical Information of China (English)

    高英俊; 班冬梅; 韩永剑; 钟夏平; 刘慧

    2004-01-01

    The valence electron structures of Al-Mg alloy with minor Sc and Zr were calculated according to the empirical electron theory(EET) in solid. The results show that because of the strong interaction of Al atom with Zr and Sc atom in melting during solidification, the Al3 Sc and Al3 (Sc1-xZrx) particles which act as heterogeneous nuclear are firstly crystallized in alloy to make grains refine. In progress of solidification, the Al-Sc, Al-Zr-Sc segregation regions are formed in solid solution matrix of Al-Mg alloy owing to the strong interaction of Al atom with Zr, Scatoms in bulk of alloy, so in the following homogenization treatment, the finer dispersed Al3 Sc and Al3 (Sc1-x Zrx) second-particles which are coherence with the matrix are precipitated in the segregation region. These finer second particles with the strong Al-Zr, Al-Sc covalent bonds can strengthen the covalent bonds in matrix of the alloy, and also enhance the hardness and strength of Al-Mg alloy. Those finer second-particles precipitated in interface of sub-grains can also strengthen the covalence bonds there, and effectively hinder the interface of sub-grains from migrating and restrain the sub-grains from growing, and cause better thermal stability of Al-Mg alloy.

  5. Model of Dees and Rotco for the 600 MeV SC

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    The accelerating frequency of the 600 MeV Synchro-Cyclotron (SC) was modulated by the varying capacity of a rotating condenser ("Rotco", the most delicate component of the SC). A 1/5-scale model, dating from the design-period of the SC, was used to study improvements to the SC RF-system, and also the acceleration of ions, first Helium and, at the time of this picture, Carbon. In the middle of the picture is the case containing the Dees. To the left, at the wide end of the cone, a rotco. Reinhold Hohbach is busy with measurements. See also 7805235 (Annual Report 1978, p.110).

  6. Nuclear Level Density and Gamma-Ray Strength Function of 43Sc

    CERN Document Server

    Bürger, A; Hilaire, S; Guttormsen, M; Harissopulos, S; Kmiecik, M; Konstantinopoulos, T; Krticka, M; Lagoyannis, A; Lönnroth, T; Mazurek, K; Norrby, M; Nyhus, H T; Perdikakis, G; Siem, S; Spyrou, A; Syed, N U H; 10.1103/PhysRevC.85.064328

    2012-01-01

    The nuclear level density and the gamma-ray strength function have been determined for 43Sc in the energy range up to 2 MeV below the neutron separation energy using the Oslo method with the 46Ti(p,alpha)43Sc reaction. A comparison to 45Sc shows that the level density of 43Sc is smaller by an approximately constant factor of two. This behaviour is well reproduced in a microscopical/combinatorial model calculation. The gamma-ray strength function is showing an increase at low gamma-ray energies, a feature which has been observed in several nuclei but which still awaits theoretical explanation.

  7. [Mitral surgery by superior biatrial septotomy].

    Science.gov (United States)

    Saade, A; Delepine, G; Lemaitre, C; Baehrel, B

    1995-01-01

    The superior biatrial septotomy approach consists of two semicircular right atrial and septal incisions joined at the superior end of the interatrial septum and extended across the dome of the left atrium, allowing exposure of the mitral valve by reflecting the ventricular side using stay sutures. From 1991 to 1993, 81 patients underwent mitral valve surgery by this technic. Mitral valve operation was combined with other cardiac procedures in 30 patients (37%) and was performed as a second operation in 21 patients (25.9%). Duration of cardiopulmonary bypass and aortic occlusion was not significantly different from that of patients operated via a conventional left atrial approach. The five hospital deaths (6.2%) were not related to this operative approach. Only 2 patients (3.3%) with preoperative in sinus rythm were discharged in atrial fibrillation after operation. In one patient (1.6%), atrioventricular block appeared at late follow-up. There were no cases of bleeding, atrioventricular nodal dysfunction or intra-atrial shunting related to the approach. This approach provides excellent exposure of the mitral valve even in unfavorable situations such as a small left atrium, dense adhesions from previous procedures or a previously implanted aortic prosthesis, without damage to various cardiac structures due to excessive traction. No retractor or vena cava repair are required. These data support a wide application of the superior biatrial septotomy approach in mitral valve surgery.

  8. Superior mesenteric artery compression syndrome - case report

    Directory of Open Access Journals (Sweden)

    Paulo Rocha França Neto

    2011-12-01

    Full Text Available Superior mesenteric artery syndrome is an entity generally caused by the loss of the intervening mesenteric fat pad, resulting in compression of the third portion of the duodenum by the superior mesenteric artery. This article reports the case of a patient with irremovable metastatic adenocarcinoma in the sigmoid colon, that evolved with intense vomiting. Intestinal transit was carried out, which showed important gastric dilation extended until the third portion of the duodenum, compatible with superior mesenteric artery syndrome. Considering the patient's nutritional condition, the medical team opted for the conservative treatment. Four months after the surgery and conservative measures, the patient did not present vomiting after eating, maintaining previous weight. Superior mesenteric artery syndrome is uncommon and can have unspecific symptoms. Thus, high suspicion is required for the appropriate clinical adjustment. A barium examination is required to make the diagnosis. The treatment can initially require gastric decompression and hydration, besides reversal of weight loss through adequate nutrition. Surgery should be adopted only in case of clinical treatment failure.A síndrome da artéria mesentérica superior é uma entidade clínica causada geralmente pela perda do tecido adiposo mesentérico, resultando na compressão da terceira porção do duodeno pela artéria mesentérica superior. Esse artigo relata o caso clínico de uma paciente portadora de adenocarcinoma de cólon sigmoide metastático irressecável, que evoluiu com vômitos incoercíveis. Realizou-se, então, trânsito intestinal que evidenciou dilatação gástrica importante, que se prolongava até a terceira porção duodenal, quadro radiológico compatível com pinçamento da artéria mesentérica superior. Diante da condição nutricional da paciente, foi optado por iniciar medidas conservadoras (porções alimentares pequenas e mais frequentes, além de dec

  9. Baculovirus display of single chain antibody (scFv using a novel signal peptide

    Directory of Open Access Journals (Sweden)

    Gonzalez Gaëlle

    2010-11-01

    Full Text Available Abstract Background Cells permissive to virus can become refractory to viral replication upon intracellular expression of single chain fragment variable (scFv antibodies directed towards viral structural or regulatory proteins, or virus-coded enzymes. For example, an intrabody derived from MH-SVM33, a monoclonal antibody against a conserved C-terminal epitope of the HIV-1 matrix protein (MAp17, was found to exert an inhibitory effect on HIV-1 replication. Results Two versions of MH-SVM33-derived scFv were constructed in recombinant baculoviruses (BVs and expressed in BV-infected Sf9 cells, N-myristoylation-competent scFvG2/p17 and N-myristoylation-incompetent scFvE2/p17 protein, both carrying a C-terminal HA tag. ScFvG2/p17 expression resulted in an insoluble, membrane-associated protein, whereas scFvE2/p17 was recovered in both soluble and membrane-incorporated forms. When coexpressed with the HIV-1 Pr55Gag precursor, scFvG2/p17 and scFvE2/p17 did not show any detectable negative effect on virus-like particle (VLP assembly and egress, and both failed to be encapsidated in VLP. However, soluble scFvE2/p17 isolated from Sf9 cell lysates was capable of binding to its specific antigen, in the form of a synthetic p17 peptide or as Gag polyprotein-embedded epitope. Significant amounts of scFvE2/p17 were released in the extracellular medium of BV-infected cells in high-molecular weight, pelletable form. This particulate form corresponded to BV particles displaying scFvE2/p17 molecules, inserted into the BV envelope via the scFv N-terminal region. The BV-displayed scFvE2/p17 molecules were found to be immunologically functional, as they reacted with the C-terminal epitope of MAp17. Fusion of the N-terminal 18 amino acid residues from the scFvE2/p17 sequence (N18E2 to another scFv recognizing CD147 (scFv-M6-1B9 conferred the property of BV-display to the resulting chimeric scFv-N18E2/M6. Conclusion Expression of scFvE2/p17 in insect cells using a BV

  10. Effects of Sc and Zr on mechanical property and microstructure of tungsten inert gas and friction stir welded aerospace high strength Al–Zn–Mg alloys

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Ying, E-mail: csudengying@163.com [School of Metallurgy and Environment, Central South University, Hunan, Changsha 410083 (China); School of Materials Science and Engineering, Central South University, Hunan, Changsha 410083 (China); State Key Laboratory for Power Metallurgy, Central South University, Hunan, Changsha 410083 (China); Peng, Bing [School of Metallurgy and Environment, Central South University, Hunan, Changsha 410083 (China); Xu, Guofu, E-mail: csuxgf66@csu.edu.cn [School of Materials Science and Engineering, Central South University, Hunan, Changsha 410083 (China); State Key Laboratory for Power Metallurgy, Central South University, Hunan, Changsha 410083 (China); Pan, Qinglin; Yin, Zhimin; Ye, Rui [School of Materials Science and Engineering, Central South University, Hunan, Changsha 410083 (China); Wang, Yingjun; Lu, Liying [Northeast Light Alloy Co. Ltd., Hei Longjiang, Harbin 150060 (China)

    2015-07-15

    New aerospace high strength Al–Zn–Mg and Al–Zn–Mg–0.25Sc–0.10Zr (wt%) alloys were welded by tungsten inert gas (TIG) process using a new Al–6.0Mg–0.25Sc–0.10Zr (wt%) filler material, and friction stir welding (FSW) process, respectively. Mechanical property and microstructure of the welded joints were investigated comparatively by tensile tests and microscopy methods. The results show that Sc and Zr can improve the yield strength and ultimate tensile strength of Al–Zn–Mg alloy by 59 MPa (23.3%) and 16 MPa (4.0%) in TIG welded joints, and by 77 MPa (23.8%) and 54 MPa (11.9%) in FSW welded joints, respectively. The ultimate tensile strength and elongation of new Al–Zn–Mg–Sc–Zr alloy FSW welded joint are 506±4 MPa and 6.34±0.2%, respectively, showing superior post welded performance. Mechanical property of welded joint is mainly controlled by its “weakest microstructural zone”. TIG welded Al–Zn–Mg and Al–Zn–Mg–Sc–Zr alloys reinforced with weld bead both failed at fusion boundaries. Secondary Al{sub 3}Sc{sub x}Zr{sub 1−x} particles originally present in parent alloy coarsen during TIG welding process, but they can restrain the grain growth and recrystallization here, thus improving welding performance. For two FSW welded joints, fracture occurred in weld nugget zone. Secondary Al{sub 3}Sc{sub x}Zr{sub 1−x} nano-particles almost can keep unchangeable size (20–40 nm) across the entire FSW welded joint, and thus provide effective Orowan strengthening, grain boundary strengthening and substructure strengthening to strengthen FSW joints. The positive effect from Sc and Zr additions into base metals can be better preserved by FSW process than by TIG welding process.

  11. Production of single chain Fab (scFab fragments in Bacillus megaterium

    Directory of Open Access Journals (Sweden)

    Dübel Stefan

    2007-11-01

    Full Text Available Abstract Background The demand on antigen binding reagents in research, diagnostics and therapy raises questions for novel antibody formats as well as appropriate production systems. Recently, the novel single chain Fab (scFab antibody format combining properties of single chain Fv (scFv and Fab fragments was produced in the Gram-negative bacterium Escherichia coli. In this study we evaluated the Gram-positive bacterium Bacillus megaterium for the recombinant production of scFab and scFvs in comparison to E. coli. Results The lysozyme specific D1.3 scFab was produced in B. megaterium and E. coli. The total yield of the scFab after purification obtained from the periplasmic fraction and culture supernatant of E. coli was slightly higher than that obtained from culture supernatant of B. megaterium. However, the yield of functional scFab determined by analyzing the antigen binding activity was equally in both production systems. Furthermore, a scFv fragment with specificity for the human C reactive protein was produced in B. megaterium. The total yield of the anti-CRP scFv produced in B. megaterium was slightly lower compared to E. coli, whereas the specific activity of the purified scFvs produced in B. megaterium was higher compared to E. coli. Conclusion B. megaterium allows the secretory production of antibody fragments including the novel scFab antibody format. The yield and quality of functional antibody fragment is comparable to the periplasmic production in E. coli.

  12. Expression and bioactivity identification of soluble MG7 scFv

    Institute of Scientific and Technical Information of China (English)

    Zhao-Cai Yu; Jie Ding; Bo-Rong Pan; Dai-Ming Fan; Xue-Yong Zhang

    2002-01-01

    AIM: To examine the molecular mass and identify thebioactivity of MG7 scFv for its application as a targetingmediator in gene therapy of gastric cancer.METHODS: Two strongly positive recombinant phage clonesscreened from MG7 recombinant phage antibody library wereseparately transfected into E. coli TG1. Plasmid wasisolated from the transfected E. coli TG1 and digested byEcoR Ⅰ and Hind Ⅲ to examine the length of exogenousscFv gene. Then, the positive recombinant phage cloneswere individually transfected into E. coli HB2151. Thetransfectant was cultured and induced by IPTG. Perplasmicextracts was prepared from the induced transfectant byosmotic shock. ELISA was used to examine the antigen-binding affinity of the soluble MG7 scFv. Immunodottingassay was adopted to evaluate the yield of soluble MG7 scFvproduced by transfected E. coli HB2151. Western blot wasused to examine the molecular mass of MG7 scFv. Finally,the nucleotide sequence of MG7 scFv was examined by DNAsequencing.RESULTS: Two positive recombinant phage clones werefound to contain the exogenous scFv gene. ELISA showedthat MG7 scFv had strong antigen-binding affinity.Immuodotting assay showed that transfected E. coli HB2151could successfully produce the soluble MG7 scFv with highyield via induction by IPTG. The molecular mass of MG7scFv was 30 kDa by western blot. DNA sequencingdemonstrated that the VH and VL genes of MG7 scFv were363bp and 321 bp, respectively.CONCLUSION: We have successfully developed the solubleMG7 scFv which possessed strong antigen-binding affinity.

  13. NiO-ScSZ and Ni 0.9Mg 0.1O-ScSZ-based anodes under internal dry reforming of simulated biogas mixtures

    Science.gov (United States)

    Shiratori, Y.; Sasaki, K.

    Solid oxide fuel cells (SOFCs) with NiO-ScSZ and Ni 0.9Mg 0.1O-ScSZ-based anodes were operated by directly feeding a fuel mixture of CH 4, CO 2 and N 2 (CH 4 to CO 2 ratio of 3:2). Stable operation under constant current load (200 mA cm -2) was achieved with a NiO-ScSZ type anode during 200 h operating hours at 900 °C. Less stable operation occurred with a Ni 0.9Mg 0.1O-ScSZ type anode. In the case of SOFC with Ni 0.9Mg 0.1O-ScSZ as the anode, the methane reforming activity was higher than that with NiO-ScSZ. This was explained by change in the microstructure promoting reforming reactions. However, the addition of MgO resulted in degradation of electrochemical performance due to increase in ohmic resistance of the anode material during operation.

  14. Encoding of the amplitude modulation of pulsatile electrical stimulation in the feline cochlear nucleus by neurons in the inferior colliculus; effects of stimulus pulse rate

    Science.gov (United States)

    McCreery, Douglas; Han, Martin; Pikov, Victor; Yadav, Kamal; Pannu, Satinderpall

    2013-10-01

    Objectives. Persons without a functional auditory nerve cannot benefit from cochlear implants, but some hearing can be restored by an auditory brainstem implant (ABI) with stimulating electrodes implanted on the surface of the cochlear nucleus (CN). Most users benefit from their ABI, but speech recognition tends to be poorer than for users of cochlear implants. Psychophysical studies suggest that poor modulation detection may contribute to the limited performance of ABI users. In a cat model, we determined how the pulse rate of the electrical stimulus applied within or on the CN affects temporal and rate encoding of amplitude modulation (AM) by neurons in the central nucleus of the inferior colliculus (ICC). Approach. Stimulating microelectrodes were implanted chronically in and on the cats' CN, and multi-site recording microelectrodes were implanted chronically into the ICC. Encoding of AM pulse trains by neurons in the ICC was characterized as vector strength (VS), the synchrony of neural activity with the AM, and as the mean rate of neuronal action potentials (neuronal spike rate (NSR)). Main results. For intranuclear microstimulation, encoding of AM as VS was up to 3 dB greater when stimulus pulse rate was increased from 250 to 500 pps, but only for neuronal units with low best acoustic frequencies, and when the electrical stimulation was modulated at low frequencies (10-20 Hz). For stimulation on the surface of the CN, VS was similar at 250 and 500 pps, and the dynamic range of the VS was reduced for pulse rates greater than 250 pps. Modulation depth was encoded strongly as VS when the maximum stimulus amplitude was held constant across a range of modulation depth. This ‘constant maximum’ protocol allows enhancement of modulation depth while preserving overall dynamic range. However, modulation depth was not encoded as strongly as NSR. Significance. The findings have implications for improved sound processors for present and future ABIs. The performance of

  15. Expression of tumor necrosis factor-α and interleukin-1β genes in the cochlea and inferior colliculus in salicylate-induced tinnitus

    Directory of Open Access Journals (Sweden)

    Chen Jin-Cherng

    2011-04-01

    Full Text Available Abstract Background Changes in the gene expressions for tumor necrosis factor-α (TNF-α and/or interleukin-1β (IL-1β during tinnitus have not been previously reported. We evaluated tinnitus and mRNA expression levels of TNF-α, IL-1β, and N-methyl D-aspartate receptor subunit 2B (NR2B genes in cochlea and inferior colliculus (IC of mice after intraperitoneal injections of salicylate. Methods Forty-eight 3-month-old male SAMP8 mice were randomly and equally divided into two groups: salicylate-treated and saline-treated. All mice were trained to perform an active avoidance task for 5 days. Once conditioned, an active avoidance task was performed 2 hours after daily intraperitoneal injections of saline, either alone or containing 300 mg/kg sodium salicylate. Total numbers of times (tinnitus score the mice climbed during the inter-trial silent period for 10 trials were recorded daily for 4 days (days 7 to 10, and then mice were euthanized for determination of mRNA expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC at day 10. Results Tinnitus scores increased in response to daily salicylate treatments. The mRNA expression levels of TNF-α increased significantly for the salicylate-treated group compared to the control group in both cochlea (1.89 ± 0.22 vs. 0.87 ± 0.07, P p = 0.0040. mRNA expression levels for the IL-1β gene also increased significantly in the salicylate group compared to the control group in both cochlea (3.50 ± 1.05 vs. 2.80 ± 0.28, p versus 1.24 ± 0.52, p = 0.0013. Linear regression analysis revealed a significant positive association between tinnitus scores and expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC. In addition, expression levels of the TNF-α gene were positively correlated with those of the NR2Bgene in both cochlea and IC; whereas, the expression levels of the IL-1β gene was positively correlated with that of the NR2B gene in IC, but not in cochlea. Conclusion We

  16. Binaural interaction in low-frequency neurons in inferior colliculus of the cat. II. Effects of changing rate and direction of interaural phase.

    Science.gov (United States)

    Yin, T C; Kuwada, S

    1983-10-01

    We used the binaural beat stimulus to study the interaural phase sensitivity of inferior colliculus (IC) neurons in the cat. The binaural beat, produced by delivering tones of slightly different frequencies to the two ears, generates continuous and graded changes in interaural phase. Over 90% of the cells that exhibit a sensitivity to changes in the interaural delay also show a sensitivity to interaural phase disparities with the binaural beat. Cells respond with a burst of impulses with each complete cycle of the beat frequency. The period histogram obtained by binning the poststimulus time histogram on the beat frequency gives a measure of the interaural phase sensitivity of the cell. In general, there is good correspondence in the shapes of the period histograms generated from binaural beats and the interaural phase curves derived from interaural delays and in the mean interaural phase angle calculated from them. The magnitude of the beat frequency determines the rate of change of interaural phase and the sign determines the direction of phase change. While most cells respond in a phase-locked manner up to beat frequencies of 10 Hz, there are some cells tht will phase lock up to 80 Hz. Beat frequency and mean interaural phase angle are linearly related for most cells. Most cells respond equally in the two directions of phase change and with different rates of change, at least up to 10 Hz. However, some IC cells exhibit marked sensitivity to the speed of phase change, either responding more vigorously at low beat frequencies or at high beat frequencies. In addition, other cells demonstrate a clear directional sensitivity. The cells that show sensitivity to the direction and speed of phase changes would be expected to demonstrate a sensitivity to moving sound sources in the free field. Changes in the mean interaural phase of the binaural beat period histograms are used to determine the effects of changes in average and interaural intensity on the phase sensitivity

  17. Exploring the word superiority effect using TVA

    DEFF Research Database (Denmark)

    Starrfelt, Randi

    Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) has been observed when written stimuli are presented very briefly or degraded by visual noise. It is unclear, however, if this is due to a lower threshold for perc...... simultaneously we find a different pattern: In a whole report experiment with six stimuli (letters or words), letters are perceived more easily than words, and this is reflected both in perceptual processing speed and short term memory capacity....

  18. de educación media superior

    Directory of Open Access Journals (Sweden)

    Enrique Cerón Ferrer

    2007-01-01

    Full Text Available El trabajo presenta los resultados obtenidos en relación al conocimiento y manejo que sobre matemáticas tienen los estudiantes de educación media superior, de los Centros de Estudios Tecnológicos y de Servicios del Distrito Federal, de diferentes carreras que se imparten en estos centros escolares, durante el año 2005. El instrumento de análisis es un cuestionario que contestaron los alumnos, la metodología utilizada es de tipo longitudinal y comparativa.

  19. EngenuitySC Commercialization and Entrepreneurial Training Project

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Meghan; Hutton, Katherine R

    2012-12-31

    A team led by EngenuitySC has performed education and outreach on development of advanced energy markets that will enable wider use of clean energy technologies. This report details the efforts that have made significant advances to improve the market place through education, outreach, and increased communications between industry members. The project resulted in two self-funded industry clusters known as the Fuel Cell Collaborative and NuHub. This project has focused on building and strengthening the leading clean energy clusters in South Carolina: nuclear energy and fuel cell technologies. For the nuclear industry, a new cluster was developed that is now known as NuHub. This cluster has already engaged over 25 nuclear industry leaders or suppliers, four public sector partners, six community economic development foundations, and nearly ten academic partners in a 175 mile radius between Augusta, Georgia and Charlotte, North Carolina. Our outreach has touched over 2,000 stakeholders through the website alone, not including the public audiences and members of the business community reached through news stories and releases that were distributed to over 620 print and online publications. NuHub has established a formal leadership structure, developed subcommittees to focus on industry issues, instituted educational programs for the workforce, and created an industry funding structure that will sustain the industry cluster and mission. NuHub has participated in a wide-variety of community building and outreach activities since its formation under this grant. In the two years since its creation in 2010, we have initiated efforts focused in four main areas that correlate with the four NuHub subcommittees including: innovation, workforce development, industry engagement, and marketing and communications. NuHub successfully raised over $160,000 in both public and private funding, which has supported work to grow the cluster and engage partners including NuScale, Fluor, and

  20. Final Technical Report – DOE Grant DE-SC0005904

    Energy Technology Data Exchange (ETDEWEB)

    Dear, Jody [Connecticut State Univ. System, Hartford, CT (United States)

    2013-10-23

    DOE grant DE-SC0005904 was allocated to fund the faculty development, curriculum development and travel to support the four institutions of the Connecticut State University System’s (CSUS) Initiative for Nanotechnology-related Equipment, Faculty Development and Curriculum Development. DOE grant DE-SC0005072 was also awarded for this program. In 2010, CSUS had identified the establishment of nanotechnology programs and infrastructure as a priority. At that time, the system set the goal of establishing an academic initiative in nanotechnology for the CSUS, beginning with the development of a series of courses at the graduate level. Implementation was planned via a collaborative effort including faculty from all four of the CSUS campuses. The CSUS Nanotechnology Working Group [CSUS NWG] was established to accomplish this goal. A faculty member from the Physics Department at Southern Connecticut State University [SCSU] was assigned the task of organizing and coordinating the work of the CSUS NWG. Representatives from each of the four CSUS campuses were appointed to join the CSUS NWG with the following initial representation: SCSU [Physics and Biology], Western Connecticut State University (WCSU) [Chemistry], Eastern Connecticut State University (ECSU) [Chemistry] and Central Connecticut State University (CCSU) [Chemistry. As a further outcome it was determined that this collaborative effort would lead to the establishment of a formal nanotechnology center, serving as the nucleus of CSUS student and faculty learning and research. This CSUS Nanotechnology Center [CSUS-NC] was to be located at Southern Connecticut State University (SCSU). The goal of this grant was to provide funding for curriculum and faculty development necessary to facilitate the development and implementation of a collaborative Graduate Certificate in Nanotechnology for the Connecticut State University System. This outcome has been successfully achieved. The courses and structure of the Graduate

  1. Structural and electronic studies of metal carbide clusterfullerene Sc2C2@Cs-C72

    Science.gov (United States)

    Feng, Yongqiang; Wang, Taishan; Wu, Jingyi; Feng, Lai; Xiang, Junfeng; Ma, Yihan; Zhang, Zhuxia; Jiang, Li; Shu, Chunying; Wang, Chunru

    2013-07-01

    We present a metal carbide clusterfullerene Sc2C2@Cs(10528)-C72, whose structure has been baffling for many years. A motional endohedral Sc2C2 cluster, special molecule geometry and electronic structure were found in Sc2C2@Cs(10528)-C72. The paramagnetic Sc2C2@Cs-C72 anion radical was successfully prepared by a chemical reduction method and hyperfine couplings in the ESR spectrum were observed.We present a metal carbide clusterfullerene Sc2C2@Cs(10528)-C72, whose structure has been baffling for many years. A motional endohedral Sc2C2 cluster, special molecule geometry and electronic structure were found in Sc2C2@Cs(10528)-C72. The paramagnetic Sc2C2@Cs-C72 anion radical was successfully prepared by a chemical reduction method and hyperfine couplings in the ESR spectrum were observed. Electronic supplementary information (ESI) available: Experimental details, HPLC chromatogram, and DFT calculations. CCDC 917712. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c3nr01739g

  2. Implementation of LTE SC-FDMA on the USRP2 Software Defined Radio Platform

    DEFF Research Database (Denmark)

    Jørgensen, Peter Bjørn; Hansen, Thomas Lundgaard; Sørensen, Troels Bundgaard;

    2011-01-01

    In this paper we discuss the implementation of a Single Carrier Frequency Division Multiple Access (SC-FDMA) transceiver running over the Universal Software Radio Peripheral 2 (USRP2). SC-FDMA is the air interface which has been selected for the uplink in the latest Long Term Evolution (LTE...

  3. Superconductivity at 3.1 K in the orthorhombic ternary silicide ScRuSi

    Science.gov (United States)

    Ruan, Bin-Bin; Wang, Xiao-Chuan; Yu, Jia; Pan, Bo-Jin; Mu, Qing-Ge; Liu, Tong; Chen, Gen-Fu; Ren, Zhi-An

    2017-02-01

    We report the synthesis, crystal structure, superconductivity and physical property characterizations of the ternary equiatomic compound ScRuSi. Polycrystalline samples of ScRuSi were prepared by an arc-melting method. The as-prepared samples were identified as the orthorhombic Co2P-type o-ScRuSi by powder x-ray diffraction analysis. Electrical resistivity measurements show o-ScRuSi to be a metal which superconducts below a T c of 3.1 K; the upper critical field μ 0 H c2(0) is estimated to be 0.87 T. The magnetization and specific heat measurements confirm the bulk type-II superconductivity in o-ScRuSi, with a specific heat jump within the BCS weak coupling limit. o-ScRuSi is the first Co2P-type superconductor to contain scandium. After annealing at 1273 K for a week, o-ScRuSi transforms into hexagonal Fe2P-type h-ScRuSi, which is a Pauli-paramagnetic metal with no superconductivity observed above 1.8 K.

  4. Characterization of early transient accumulation of PrP(Sc) in immune cells.

    Science.gov (United States)

    Elhelaly, Abdelazim Elsayed; Inoshima, Yasuo; Ishiguro, Naotaka

    2013-09-27

    PrP(Sc) is known to elicit no specific immune response and the immune cells are suspected to support its accumulation. In the present study, we investigated the response of some immune cell types to PrP(Sc) to characterize an observed early transient accumulation of PrP(Sc). After cells were treated with PrP(Sc)-brain homogenate, PrP(Sc) was transiently accumulated for the first 8-12h post-exposure then completely cleared by the 5th day of the experiment. The accumulated PrP(Sc) was not a de novo product of the cell PrP(C). Further investigation of this phenomenon revealed some potential factors influencing it. These factors included cholesterol homeostasis, temperature, the degradation power of the cell and the availability of sufficient PrP(C). Our in vitro results suggest that immune cells, especially macrophages are potential risk factors for the accumulation and intercellular spread of PrP(Sc) if the complete clearance of PrP(Sc) were not fulfilled.

  5. 33 CFR 110.72c - Lake Murray, S.C.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lake Murray, S.C. 110.72c Section 110.72c Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.72c Lake Murray, S.C. (a) The area beginning at the 125...

  6. Hydrogenation reactions using scCO2 as a solvent in microchannel reactors.

    Science.gov (United States)

    Kobayashi, Juta; Mori, Yuichiro; Kobayashi, Shū

    2005-05-28

    We have developed an effective microfluidic system for hydrogenation reactions in scCO(2); the reactions proceeded very rapidly (within 1 second), by making the best use of scCO(2) and utilizing the large specific interfacial area of the microchannel reactor, and high reaction productivity was attained in each channel.

  7. High-efficient physical adsorption and detection of formaldehyde using Sc- and Ti-decorated graphdiyne

    Science.gov (United States)

    Chen, Xi; Gao, Pengfei; Guo, Lei; Wen, Yanni; Fang, Dangqi; Gong, Baihua; Zhang, Yang; Zhang, Shengli

    2017-03-01

    In sensitive analysis, the ultimate limit is to achieve reliable detection on trace amount of molecules. In this work, Sc- and Ti-decorated graphdiyne were proposed as promising materials for high-efficient molecular detection. Using density functional theory calculations, we investigated the electronic response of single Sc- and Ti-atom-decorated graphdiyne to HCHO (as a typical air pollutant). Thermodynamic analysis predicted that Sc or Ti adatom could be stabilized on the corner sites of single-layer graphdiyne sheet, with migration barriers high enough to prevent Sc or Ti adatom aggregation. The adsorption of HCHO on Sc- or Ti-decorated graphdiyne was found stronger than on pristine graphene or graphdiyne, which provides a prerequisite for molecular sensing. The electronegativity of HCHO leads to strong electronic attraction from Sc or Ti adatom to HCHO, resulting in a remarkable decrease of carrier density in graphdiyne. On Ti-decorated graphdiyne, the electronic attraction of HCHO appears to be stronger than on Sc-decorated graphdiyne and changes the system from metal to n-doped semiconductor. Quantum transport calculations show a decrease of current caused by the adsorbed HCHO. The results systematically exhibit the electronic response of Sc- or Ti-decorated graphdiyne to HCHO and suggest them as promising materials for molecule detection.

  8. Curriculum (Study Programme) for the M.Sc., Medialogy, at Aalborg University in Copenhagen

    DEFF Research Database (Denmark)

    Serafin, Stefania; Nordahl, Rolf; Lavatino, Salvatore

    2004-01-01

    Defining and describing the education, M.Sc., Medialogy. The curriculum (Study Programme) describes semesters, themes, projectunits, courses and contents of the eduation. offered at Aalborg University in Copenhagen.......Defining and describing the education, M.Sc., Medialogy. The curriculum (Study Programme) describes semesters, themes, projectunits, courses and contents of the eduation. offered at Aalborg University in Copenhagen....

  9. PRODUCTION, ISOLATION AND SPECTROSCOPIC STUDIES OF THE ENDOHEDRAL FULLERENE Sc2@C80 (Ⅰ-Ⅲ)

    Institute of Scientific and Technical Information of China (English)

    Chunru Wang; Lihua Gan; Chunli Bai; Hisanori Shinohara

    2004-01-01

    The isolation of multiple-isomers of Sc2@C80 (Ⅰ, Ⅱ, Ⅲ) endohedral metallofullerenes is reported for the first time. The new C80-based Sc-metallofullerenes are characterized by UV-Vis-NIR absorption spectroscopy and detailed chromatographic retention time data. A close relationship between the isomer structure and the corresponding HPLC retention time of the metallofullerenes is presented.

  10. Establishment and characterization of Roberts syndrome and SC phocomelia model medaka (Oryzias latipes).

    Science.gov (United States)

    Morita, Akihiro; Nakahira, Kumiko; Hasegawa, Taeko; Uchida, Kaoru; Taniguchi, Yoshihito; Takeda, Shunichi; Toyoda, Atsushi; Sakaki, Yoshiyuki; Shimada, Atsuko; Takeda, Hiroyuki; Yanagihara, Itaru

    2012-06-01

    Roberts syndrome and SC phocomelia (RBS/SC) are genetic autosomal recessive syndromes caused by establishment of cohesion 1 homolog 2 ( ESCO 2) mutation. RBS/SC appear to have a variety of clinical features, even with the same mutation of the ESCO2 gene. Here, we established and genetically characterized a medaka model of RBS/SC by reverse genetics. The RBS/SC model was screened from a mutant medaka library produced by the Targeting Induced Local Lesions in Genomes method. The medaka mutant carrying the homozygous mutation at R80S in the conserved region of ESCO2 exhibited clinical variety (i.e. developmental arrest with craniofacial and chromosomal abnormalities and embryonic lethality) as characterized in RBS/SC. Moreover, widespread apoptosis and downregulation of some gene expression, including notch1a, were detected in the R80S mutant. The R80S mutant is the animal model for RBS/SC and a valuable resource that provides the opportunity to extend knowledge of ESCO2. Downregulation of some gene expression in the R80S mutant is an important clue explaining non-correlation between genotype and phenotype in RBS/SC.

  11. SC-535, a Novel Oral Multikinase Inhibitor, Showed Potent Antitumor Activity in Human Melanoma Models

    Directory of Open Access Journals (Sweden)

    Xin Chen

    2013-07-01

    Full Text Available Background: Melanoma is considered as one of the most aggressive and deadliest cancers and current targeted therapies of melanoma often suffer limited efficacy or drug resistance. Discovery of novel multikinase inhibitors as anti-melanoma drug candidates is still needed. Methods: In this investigation, we assessed the in vitro and in vivo anti-melanoma activities of SC-535, which is a novel small molecule multikinase inhibitor discovered by us recently. We analyzed inhibitory effects of SC-535 on various melanoma cell lines and human umbilical vascular endothelial cells (HUVEC in vitro. Tumor xenografts in athymic mice were used to examine the in vivo activity of SC-535. Results: SC-535 could efficiently inhibit vascular endothelial growth factor receptor (VEGFR 1/2/3, B-RAF, and C-RAF kinases. It showed significant antiangiogenic potencies both in vitro and in vivo and considerable anti-proliferative ability against several melanoma cell lines. Oral administration of SC-535 resulted in dose-dependent suppression of tumor growth in WM2664 and C32 xenograft mouse models. Studies of mechanisms of action indicated that SC-535 suppressed the tumor angiogenesis and induced G2/M phase cell cycle arrest in human melanoma cells. SC-535 possesses favorable pharmacokinetic properties. Conclusion: All of these results support SC-535 as a potential candidate for clinical studies in patients with melanoma.

  12. 33 CFR 165.708 - Safety/Security Zone; Charleston Harbor and Cooper River, Charleston, SC.

    Science.gov (United States)

    2010-07-01

    ... Harbor and Cooper River, Charleston, SC. 165.708 Section 165.708 Navigation and Navigable Waters COAST... Guard District § 165.708 Safety/Security Zone; Charleston Harbor and Cooper River, Charleston, SC. (a... Cooper River. All coordinates referenced use datum: NAD 1983. (2) All waters within 100 yards of...

  13. 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to inhibit hepatocellular carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Meili, E-mail: fumeilidrlinyi@tom.com [Department of Infectious Disease, Linyi People' s Hospital, Linyi 276000 (China); Wan, Fuqiang [Department of Head and Neck Surgery, Linyi Tumor Hospital, Linyi 276000 (China); Li, Zhengling [Department of Nursing, Tengzhou Central People' s Hospital, Tengzhou 277500 (China); Zhang, Fenghua [Department of Operating Room, Linyi People' s Hospital, Linyi 276000 (China)

    2016-03-04

    The aim of the present study is to investigate the potential anti-hepatocellular carcinoma (HCC) cell activity by 4SC-202, a novel class I HDAC inhibitor (HDACi). The associated signaling mechanisms were also analyzed. We showed that 4SC-202 treatment induced potent cytotoxic and proliferation–inhibitory activities against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, adding 4SC-202 in HCC cells activated mitochondrial apoptosis pathway, which was evidenced by mitochondrial permeability transition pore (mPTP) opening, cytochrome C cytosol release and caspase-3/-9 activation. Inhibition of this apoptosis pathway, by caspase-3/-9 inhibitors, mPTP blockers, or by shRNA-mediated knockdown of cyclophilin-D (Cyp-D, a key component of mPTP), significantly attenuated 4SC-202-induced HCC cell death and apoptosis. Reversely, over-expression of Cyp-D enhanced 4SC-202's sensitivity in HCC cells. Further studies showed that 4SC-202 induced apoptosis signal-regulating kinase 1 (ASK1) activation, causing it translocation to mitochondria and physical association with Cyp-D. This mitochondrial ASK1-Cyp-D complexation appeared required for mediating 4SC-202-induced apoptosis activation. ASK1 stable knockdown by targeted-shRNAs largely inhibited 4SC-202-induced mPTP opening, cytochrome C release, and following HCC cell apoptotic death. Together, we suggest that 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to potently inhibit human HCC cells. - Highlights: • 4SC-202 exerts potent anti-proliferative and cytotoxic activity against established/primary HCC cells. • SC-202-induced anti-HCC cell activity relies on caspase-dependent apoptosis activation. • 4SC-202 activates Cyp-D-dependent mitochondrial apoptosis pathway in HCC cells. • 4SC-202 activates ASK1 in HCC cells, causing it translocation to mitochondria. • Mitochondrial ASK1-Cyp-D complexation mediates 4SC-202's activity in HCC cells.

  14. Effect of Sc addition on microstructure and mechanical properties of 1460 alloy

    Directory of Open Access Journals (Sweden)

    Juan Ma

    2014-02-01

    Full Text Available The effect of minor addition of Sc on microstructure, age hardening behavior, tensile properties and fracture morphology of 1460 alloy have been studied. It is found that Sc content increase from 0.11 wt% to 0.22 wt% is favorable for grain refinement in as-cast alloy but results in a coarsening of Cu-rich particles. The alloy with 0.11 wt% Sc exhibits enhanced mechanical properties and age hardening effect. Transmission electron microscopy (TEM investigations on the alloy with 0.11 wt% Sc have suggested that a large amount of Al3(Sc, Zr particles precipitated at the earlier aging may inhibit recrystallization effectively.

  15. Homogenization and Recrystallization of Al-6Mg Alloys with and without Sc and Zr

    Institute of Scientific and Technical Information of China (English)

    姜锋; 尹志民; 黄伯云; 贺跃辉; 陈苏里

    2004-01-01

    Plates of Al-6Mg alloys with and without scandium were prepared by semi-continuous cast, homogenization, hot-rolled, cold-rolled and annealing. Based on studying of effects of temperature and time on hardness and conductivity during homogenization, it was found that homogenization of ingot with Sc and Zr can result in dispersion strengthening. Recrystallization temperature of alloys was studied by hardness method and optical metallographic method. Staring recrystallization temperature of Al-6Mg alloys with Sc and Zr is 375 ℃, increasing by 150 ℃ than Al-6Mg alloys without Sc and Zr. Mechanical properties (σb, σ0.2, δ) of hot-rolled alloy with Sc and Zr are 400 MPa, 280 MPa and 18%; cold-rolled and anneal alloy with Sc and Zr are 420 MPa, 310 MPa and 12% respectively.

  16. Scandium-44: benefits of a long-lived PET radionuclide available from the (44)Ti/(44)Sc generator system.

    Science.gov (United States)

    Roesch, F

    2012-07-01

    (44)Ti/(44)Sc radionuclide generators are of interest for molecular imaging. The 3.97 hours half-life of (44)Sc and its high positron branching of 94.27% may stimulate the application of (44)Sc-labeled PET radiopharmaceuticals. This review describes the current status of (44)Ti production, (44)Ti/(44)Sc radionuclide generator development, post-processing of generator eluates towards medical application, identification of ligands adequate to Sc(III) co-ordination chemistry, proof-of-principle labeling of (44)Sc-DOTA-octreotides, investigation of in vitro and in vivo parameters, and initial applications for molecular imaging - both in small animals and humans.

  17. Pancreaticoduodenectomy with early superior mesenteric artery dissection

    Institute of Scientific and Technical Information of China (English)

    Yu-Fei Xu; Zuo-Jin Liu; Jian-Ping Gong

    2010-01-01

    BACKGROUND: Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive human tumors. At present, surgical resection is the only potentially curative treatment. Early neck division is inadequate when invasion of the superior mesenteric artery (SMA) is suspected or in cases of replaced or accessory right hepatic artery. Malignant periampullary tumors often invade retroperitoneal peripancreatic tissues and a positive resection margin is associated with a poor long-term survival. DATA SOURCES: English-language medical databases, PubMed, ELSEVIER and SPRINGERLINK, were searched for articles on"posterior approach pancreaticoduodenectomy","superior mesenteric artery ifrst approach", "retroperitoneal tissue","hanging maneuver", and related topics. RESULTS:The modiifcation allowed the surgeon to early identify the nonresectability of a replaced right hepatic artery if present, enabling complete dissection of the right side of the SMA and portal vein as well as complete excision of the retroportal pancreatic lamina. CONCLUSION: Pancreaticoduodenectomy with early retro-pancreatic dissection is a useful and safe technical variant, which is indicated for the improvement of the safety and curative effect of the procedure.

  18. Radiation treatment of superior sulcus lung carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Millar, J.; Ball, D.; Worotniuk, V.; Smith, J.; Crennan, E.; Bishop, M. [Peter MacCallum Cancer Inst., East Melbourne, VIC (Australia)

    1996-02-01

    The survival of patients with superior sulcus lung carcinoma and the effects of treatment were reviewed. From a prospective database of 4123 consecutive new patients with lung carcinoma, 131 (3.2%) cases of superior sulcus lung carcinoma were identified. Seventy-four patients were planned to receive radiation with palliative intent, 53 radical radiotherapy and one was observed only. The remaining three patients, with small-cell carcinoma, were treated with chemotherapy with or without radiotherapy. Of the 53 radically treated patients, nine were treated with pre-operative radiation prior to intended radical resection. Analysis was carried out on the effect on survival of performance status, nodal involvement, weight loss, vertebral body or rib involvement, treatment intent and radical combined modality treatment compared with radical radiation alone. The estimated median survival for the whole group was 7.6 months; for those treated radically it was 18.3 months, while for the palliatively treated patients it was 3.7 months. Radically treated patients with no initial nodal involvement had an estimated median survival of 22 months, while radically treated patients with nodal involvement had an estimated median survival of 8.4 months (P = 0.003). There were no statistically significant differences in survival between radically treated patients grouped according to initial weight loss, performance status, or vertebral body and rib involvement. Patients treated with pre-operative radiation did not survive significantly longer than patients treated with radiation alone, although the numbers are small. 33 refs., 2 tabs., 4 figs.

  19. Studies on zooplankton of Lago Paione Superiore

    Directory of Open Access Journals (Sweden)

    Patrizia COMOLI

    1999-08-01

    Full Text Available We report here the results of a three year study on the zooplankton of Lago Paione Superiore, an acid sensitive lake above the tree line in the Italian Alps. The research was carried out within MOLAR, an EC-founded Project on “Measuring and Modeling the dynamic response of remote mountain lakes ecosystems to environmental change”. This study comes after a series of investigations on the effects of acidification, in which we documented the changes occurred with decreasing water pHs, by comparing the recent situation with that in the literature of the 40s, and reconstructed the beginning of anthropogenic disturbance through an analysis of the past cladocera assemblages archived in the lake sediments. A characteristic pattern in seasonal periodicity is a transition from a community dominated by small zooplankton (August to a community where the large particle-feeder Daphnia longispina dominates. This is a typical pattern observed in fishless, copepod-cladocera lakes. Regardless from which food is able to exploit, Daphnia population of Lago Paione Superiore is composed by well-fed organisms, visually rich in lipids, able to produce more than one generation/ year of parthenogenetic females at density levels which are rather high in an oligotrophic high mountain lake.

  20. INTERVIU CU DOAMNA SIMONA CAROBENE, ADMINISTRATORUL SC PROIECT MOZAIC SRL

    Directory of Open Access Journals (Sweden)

    Gheorghe Pascaru

    2013-12-01

    Full Text Available Fabrica de mozaic, înregistrată la Oficiul Registrului Comerţului în aprilie 2012 a luat fiinţă în cadrul unui proiect cu finanţare europeană nerambursabilă și are în prezent statutul de unitate protejată autorizată. În cadrul acesteia sunt angajați 10 tineri post instituţionalizați, pentru care integrarea în viaţa socială şi profesională este dificilă. Întreprinderea socială SC Proiect Mozaic SRL este rezultatul întâlnirii dintre sectorul social, non-profit şi sectorul business, deoarece are la bază un parteneriat cu un important grup de firme din domeniul construcţiilor şi amenajărilor interioare din București. În paralel cu activitatea de producţie a mozaicului, ocazional, Proiect Mozaic oferă către clienți și servicii de ambalare și asamblare produse.

  1. Preliminary Tests Of The Decris-sc Ion Source

    CERN Document Server

    Efremov, A; Bechterev, V; Bogomolov, S L; Bondarenko, P G; Datskov, V I; Dmitriev, S; Drobin, V; Lebedev, A; Leporis, M; Malinowski, H; Nikiforov, A; Paschenko, S V; Seleznev, V; Shishov, Yu A; Smirnov, Yu; Tsvineva, G; Yakovlev, B; Yazvitsky, N Yu

    2004-01-01

    A new "liquid He-free" superconducting Electron Cyclotron Resonance Ion Source DECRIS-SC, to be used as injector for the IC-100 small cyclotron, has been designed by FLNR and LHE JINR. The main feature is that a compact refrigerator of Gifford-McMahon type is used to cool the solenoid coils. For the reason of very small cooling power at 4.2 K (about 1 W) our efforts were to optimize the magnetic structure and minimize an external heating of the coils. The maximum magnetic field strength is 3 T and 2 T in injection and extraction region respectively. For the radial plasma confinement a hexapole made of NdFeB permanent magnet is used. The source will be capable of ECR plasma heating using different frequencies (14 GHz or 18 GHz). To be able to deliver usable intensities of solids, the design is also allow axial access for evaporation oven and metal samples using the plasma sputtering technique. Very preliminary results of the source test are presented.

  2. Spectrophotometric Distances to Galactic H\\,{\\sc{ii}} Regions

    CERN Document Server

    Moisés, A P; Figuerêdo, E; Blum, R D; Conti, P S; Barbosa, C L

    2010-01-01

    We present a near infrared study of the stellar content of 35 H\\,{\\sc{ii}} regions in the Galactic plane. In this work, we have used the near infrared domain $J-$, $H-$ and $K_{s}-$ band color images to visually inspect the sample. Also, color-color and color-magnitude diagrams were used to indicate ionizing star candidates, as well as, the presence of young stellar objects such as classical TTauri Stars (CTTS) and massive young stellar objects (MYSOs). We have obtained {\\it Spitzer} IRAC images for each region to help further characterize them. {\\it Spitzer} and near infrared morphology to place each cluster in an evolutionary phase of development. {\\it Spitzer} photometry was also used to classify the MYSOs. Comparison of the main sequence in color-magnitude diagrams to each observed cluster was used to infer whether or not the cluster kinematic distance is consistent with brightnesses of the stellar sources. We find qualitative agreement for a dozen of the regions, but about half the regions have near infr...

  3. Transition energy and oscillator strength of Sc18+ion

    Institute of Scientific and Technical Information of China (English)

    Wang Zhi-Wen; Yang Di; Hu Mu-Hong; Han Qiu-Ju; Li Jin-Ying

    2005-01-01

    The transition energies and the dipole oscillator strengths for the 1s22s-1s2np (2 ≤ n ≤ 9) and 1s22p-1s2nd (3≤n ≤ 9) of lithium-like Sc18+ ion are calculated by using the full core plus correlation method. The fine structure splittings of 1s2np and 1s2nd (n ≤ 9) states are determined from the expectation values of spin-orbit and spin-otherorbit interaction operators. The quantum defects of these series, as function of principal quantum number n, are obtained. The agreement between the f-values obtained from three alternative formulae is excellent. Comparisons of our results with experimental data available in the literature are carried out. Combining the single-channel quantum defect theory with the discrete oscillator strengths obtained in this work, this paper obtains the behaviour of discrete oscillator strengths and oscillator strength densities corresponding to the bound-free transitions adjacent to ionization threshold.

  4. Final Technical Report for DE-SC0012297

    Energy Technology Data Exchange (ETDEWEB)

    Dell' Antonio, Ian [Brown Univ., Providence, RI (United States)

    2017-08-01

    This is the final report on the work performed in award DE-SC0012297, Cosmic Frontier work in support of the LSST Dark Energy Science Collaboration's work to develop algorithms, simulations, and statistical tests to ensure optimal extraction of the dark energy properties from galaxy clusters observed with LSST. This work focused on effects that could produce a systematic error on the measurement of cluster masses (that will be used to probe the effects of dark energy on the growth of structure). These effects stem from the deviations from pure ellipticity of the gravitational lensing signal and from the blending of light of neighboring galaxies. Both these effects are expected to be more significant for LSST than for the stage III experiments such as the Dark Energy Survey. We calculate the magnitude of the mass error (or bias) for the first time and demonstrate that it can be treated as a multiplicative correction and calibrated out, allowing mass measurements of clusters from gravitational lensing to meet the requirements of LSST's dark energy investigation.

  5. Domain structure and phase transition in Sc-doped zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Brunauer, G.; Boysen, H.; Frey, F. [Institute for Crystallography und Applied Mineralogy, LMU Muenchen, Munich (Germany); Ehrenberg, H. [Institute for Materials Science, TU Darmstadt, Darmstadt (Germany)

    2002-01-21

    The temperature dependence of the domain structure associated with the ferroelastic phase transition (Fm{sup 3-bar}m{r_reversible}R{sup 3-bar}m) in ZrO{sub 2} doped with 11% Sc{sub 2}O{sub 3} has been determined from a peak shape analysis of high-resolution synchrotron x-ray powder diffraction data. In the temperature region of coexisting phases the observed characteristic anisotropic broadening and asymmetry of the lines is modelled by three different phases: a main rhombohedral phase, a distorted rhombohedral phase with a smaller c/a ratio, and a cubic phase. The latter two are assigned to the internal structure of the domain walls between two adjacent twin domains. The size and amount of the cubic phase show an initially slow increase with temperature followed by a very steep increase and a slow one after that. The size of the (main) rhombohedral domains remains nearly constant, while (micro-) strain in the distorted regions gradually decreases. (author)

  6. Downregulation of the Musca domestica peptidoglycan recognition protein SC (PGRP-SC) leads to overexpression of antimicrobial peptides and tardy pupation.

    Science.gov (United States)

    Gao, Yifu; Tang, Ting; Gu, Jihai; Sun, Lingling; Gao, Xiaobin; Ma, Xianyong; Wang, Xiaochun; Liu, Fengsong; Wang, Jianhui

    2015-10-01

    PGRP (peptidoglycan recognition protein) is a conserved protein family that recognizes the peptidoglycan in bacterial cell wall and causes the activation of various innate immune responses. Previous studies have reported that PGRP-SCs in Drosophila dampen the activation of Immune Deficiency (Imd) pathway to microbial infection, and participate in the lifespan extension of the insects. To facilitate understanding the function of PGRP-SCs from an evolutionary angle, we identified and functionally characterized the PGRP-SC gene in the housefly Musca domestica, a species that has adapted to a septic environment much harsher than the natural habitat of Drosophila. The gene designated as MdPGRP-SC was found most abundantly expressed in the 3rd instar larvae, and is expressed at this developmental stage predominantly in the gut. MdPGRP-SC was virtually unchanged in whole larvae after a septic injury at the second larval instar, while two antimicrobial peptides (AMPs), diptericin and attacin, were upregulated in the first 24h but not later. Through dsRNA microinjection, MdPGRP-SC was knocked down by RNA interference (RNAi), and caused the significant increased expression of diptericin and attacin. The pupation of MdPGRP-SC-depleted larvae was severely suppressed compared to controls. Opposite to the expression trend of MdPGRP-SC, a spontaneous active expression of diptericin and attacin was found in pre-pupae but not in third instar larvae. Taken together, our study reveals that downregulation of MdPGRP-SC leads to the overexpression of the AMPs, and is involved in the larvae-to-pupa transition of housefly.

  7. Cochlear implant outcomes in patients with superior canal dehiscence

    NARCIS (Netherlands)

    Puram, Sidharth V.; Roberts, Daniel S.; Niesten, Marlien E F; Dilger, Amanda E.; Lee, Daniel J.

    2015-01-01

    Objective: To determine whether adult cochlear implant (CI) users with superior canal dehiscence syndrome (SCDS) or asymptomatic superior semicircular canal dehiscence (SCD) have different surgical, vestibular, and audiologic outcomes when compared to CI users with normal temporal bone anatomy. Meth

  8. Avance normativo del SC 8 de AENOR “Conservación, restauración y rehabilitación de edificios” = Standardisation Advance of AENOR SC 8 “Conservation, Restoration and Rehabilitation of Buildings”

    OpenAIRE

    Recopar, Editor

    2014-01-01

    Avance normativo del SC 8 de AENOR “Conservación, restauración y rehabilitación de edificios” = Standardisation Advance of AENOR SC 8 “Conservation, Restoration and Rehabilitation of Buildings”

  9. The Superior Transvelar Approach to the Fourth Ventricle and Brainstem

    OpenAIRE

    Ezer, Haim; Banerjee, Anirban Deep; Bollam, Papireddy; Guthikonda, Bharat; Nanda, Anil

    2012-01-01

    Objective The superior transvelar approach is used to access pathologies located in the fourth ventricle and brainstem. The surgical path is below the venous structures, through the superior medullary velum. Following splitting the tentorial edge, near the tentorial apex, the superior medullary velum is split in the cerebello-mesencephalic fissure. Using the supracerebellar infratentorial, transtentorial or parietal interhemispheric routes, the superior medullary velum is approached. Splittin...

  10. Radiolabeling of DOTATOC with the long-lived positron emitter {sup 44}Sc

    Energy Technology Data Exchange (ETDEWEB)

    Pruszynski, Marek; Majkowska-Pilip, Agnieszka [Centre of Radiochemistry and Nuclear Chemistry, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warszawa (Poland); Loktionova, Natalia S.; Eppard, Elisabeth [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, Fritz-Strassmann-Weg 2, D-55128 Mainz (Germany); Roesch, Frank, E-mail: frank.roesch@uni-mainz.de [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, Fritz-Strassmann-Weg 2, D-55128 Mainz (Germany)

    2012-06-15

    The positron-emitting radionuclide {sup 44}Sc with a half-life of 3.97 h and a {beta}{sup +} branching of 94.3% is of potential interest for clinical PET. As so far it is available from a {sup 44}Ti/{sup 44}Sc generator in Mainz, where long-lived {sup 44}Ti decays to no-carrier-added (nca) {sup 44}Sc. The {sup 44}Sc is a trivalent metal cation and should be suitable for complexation with many well established bifunctional chelators conjugated to peptides or other molecular targeting vectors. Thus, the aim of this work was to investigate the potential of {sup 44}Sc for labeling of DOTA-conjugated peptides. DOTA-D-Phe{sup 1}-Tyr{sup 3}-octreotide (DOTATOC) was used as a model molecule to study and optimize labeling procedure. Reaction parameters such as buffer conditions, concentration of peptide, pH range, reaction temperature and time were optimized. Addition of 21 nmol of DOTATOC to {sup 44}Sc in ammonium acetate buffer pH 4.0 provided labeling yields >98% within 25 min of heating in an oil-bath at 95 Degree-Sign C. This time can be reduced to 3 min only by applying microwave supported heating. {sup 44}Sc-DOTATOC was found to be stable in 0.9% NaCl, PBS pH 7.4, fetal calf and human serums, and also in the presence of competing metal cations (Fe{sup 3+}, Ca{sup 2+}, Cu{sup 2+}, Mg{sup 2+}), as well as other ligand competitors, like EDTA and DTPA, even after almost 25 h incubation at 37 Degree-Sign C. Present study shows that nca {sup 44}Sc forms stable complexes with the macrocyclic ligand DOTA and that {sup 44}Sc-DOTATOC and analog targeting vectors may be synthesized for further preclinical and clinical investigations. - Highlights: Black-Right-Pointing-Pointer Labeling of somatostatin analouges with positron emitter {sup 44}Sc was tested. Black-Right-Pointing-Pointer DOTATOC was labeled with {sup 44}Sc isotope. Black-Right-Pointing-Pointer Optimal conditions for {sup 44}Sc-DOTATOC synthesis were found. Black-Right-Pointing-Pointer Stability of {sup 44}Sc

  11. 14 CFR 385.7 - Exercise of authority by superiors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Exercise of authority by superiors. 385.7... Exercise of authority by superiors. Any assignment of authority to a staff member other than the Chief... Department's principle of management responsibility, the superior may choose to exercise the assigned power...

  12. 超导ECR离子源DECRIS-SC2%Project of the Superconducting ECR Ion Source DECRIS-SC2

    Institute of Scientific and Technical Information of China (English)

    V.V.Bekhterev; V.V.Seleznev; A.Shishov; G.P.Tsvineva; N.YU.Yazvitsky; B.I.Yakovlev; S.L.Bogomolov; V.I.Datskov; V.M.Drobin; S.N.Dmitriev; A.A.Efremov; V.N.Loginov; A.N.Lebedev; H.Malinowski

    2007-01-01

    A new compact version of the"liquid He-free"superconducting Electron Cyclotron Resonance Ion Source,to be used as an injector for the U-400M cyclotron,is presently under construction at the FLNR in collaboration with LHE(JINR).The axial magnetic field of the source is created by the superconducting magnet,and the NdFeB hexapole is used for the radial plasma confinement.The microwave frequency of 14GHz will be used for ECR plasma heating.The DECRIS-SC2 superconducting magnet is designed for the induction of a magnetic field on the axis of the source of up to 1.4T (extraction side) and 1.9T (injection side) at nominal current of 75A.Cooling of the coils is carried out by GM cryocooler with cooling power of 1W at the temperature 4.5K.The basic design features of the superconducting magnet and of the ion source are presented.The main parts of the source are in production.The first beam test of the source is expected in the beginning of 2007.

  13. A {sup 44}Ti/{sup 44}Sc radionuclide generator for potential application of {sup 44}Sc-based PET-radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Filosofov, D.V. [Joint Institute of Nuclear Research, Dubna (Russian Federation). DLNP; Loktionova, N.S.; Roesch, F. [University of Mainz (Germany). Institute of Nuclear Chemistry

    2010-07-01

    {sup 44}Ti/{sup 44}Sc radionuclide generators are of interest for molecular imaging. The 3.97 h half-life of {sup 44}Sc and its high positron branching of 94% may stimulate the application of {sup 44}Sc labelled PET radiopharmaceuticals. However, both {sup 44}Ti production and {sup 44}Ti/{sup 44}Sc generator design represent challenges for basic radiochemistry. About 5 mCi (185 MBq) of {sup 44}Ti were obtained via the Sc(p, 2n) nuclear reaction. {sup 44}Ti was separated from 1.5 g of massive scandium targets in multi-step procedures, including exchange chromatography on cation exchange resin (AG 50W-X8, 200-400 mesh, H{sup +}-form). In order to design a robust {sup 44}Ti/{sup 44}Sc generator concept, distribution coefficients of Ti(IV) and Sc(III) on both AG 1-X8 (200-400 mesh, Cl{sup -}-form) and AG 50W-X8 (200-400 mesh, H{sup +}-form) resins eluted with HCl and HCl/H{sub 2}C{sub 2}O{sub 4} solution of various concentrations were investigated systematically. Optimal conditions for efficient separations of both radionuclides have been determined for AG 1-X8 resin and mixtures of 0.07 M HCl and 0.005 M H{sub 2}C{sub 2}O{sub 4}. A 5 mCi generator was prepared on an AG 1-X8 column (H=150 mm, D=3 mm, V{sub 0}=0.55 mL). The system achieved elution of 180 MBq {sup 44}Sc in 20 mL of eluate solution. The breakthrough of {sup 44}Ti is 90 Bq. This corresponds to an excellent separation factor of 2 x 10{sup 6}. In the context of long-term stability of {sup 44}Ti/{sup 44}Sc generators, a ''reverse'' type of washing steps after each elution using 0.07 M HCl/0.005 M H{sub 2}C{sub 2}O{sub 4} mixtures appeared to be essential. (orig.)

  14. Superiority: China Mobile in the competition

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The market share between China Mobile and China Unicom has stabilized since 2002.It is found that China Mobile has the superiority in the competition, for example, the scissors movement between its revenue and cost indicates that it has a strong profit generating ability and there is enough room for it to reduce the price.The ratio between its price (marginal income) and marginal cost indicates that there is a very distant limit for it to reduce the price.Its demand is obviously flexible with the price, but it does not use the price weapon abundantly.The reason for the stabilization of the market is that China Mobile withdrew from the competition.

  15. MRI manifestations of enlarged superior ophthalmic vein

    Institute of Scientific and Technical Information of China (English)

    WEI Rui-li; MA Xiao-ye; CAI Ji-ping; ZHU Huang

    2002-01-01

    Objective:To assess MRI in the evaluation of enlarged superior ophthalmic vein (SOV). Methods: MRI manifestations and etiology of forty-six patients with enlarged SOV were analyzed. Results: SOV enlargement was noted to occur in carotid-cavernous fistula, ophthalmic Graves'disease, Tolosa-Hunt syndrome, inflammation at the apex of the orbit, orbital pseudotumor and thrombosis of cavernous sinus. The dilated vein appeared as signal void tubular shadows on both T1 and T2 weighted images. The diameter of the enlarged vein was 3.5-6.0 mm. Extraocular muscle enlargement, orbital pathologies, enlarged carotid cavernous sinus etc were also revealed by MRI. Conclusion: The dilated SOV may be well demonstrated by MRI. The etiological diagnosis of enlarged SOV can be made in combination with the associated findings.

  16. Lightning activity during the 1999 Superior derecho

    Science.gov (United States)

    Price, Colin G.; Murphy, Brian P.

    2002-12-01

    On 4 July 1999, a severe convective windstorm, known as a derecho, caused extensive damage to forested regions along the United States/Canada border, west of Lake Superior. There were 665,000 acres of forest destroyed in the Boundary Waters Canoe Area Wilderness (BWCAW) in Minnesota and Quetico Provincial Park in Canada, with approximately 12.5 million trees blown down. This storm resulted in additional severe weather before and after the occurrence of the derecho, with continuous cloud-to-ground (CG) lightning occurring for more than 34 hours during its path across North America. At the time of the derecho the percentage of positive cloud-to-ground (+CG) lightning measured by the Canadian Lightning Detection Network (CLDN) was greater than 70% for more than three hours, with peak values reaching 97% positive CG lightning. Such high ratios of +CG are rare, and may be useful indicators of severe weather.

  17. Analgesia em modelo animal superior para ortopedia

    OpenAIRE

    Oliveira MT, Maria Teresa; Potes, José Alberto; Queiroga, Cristina; Castro, José António; Pereira, Alfredo; Reis, Joana

    2015-01-01

    O teste de novos biomateriais para aplicações clínicas em ortopedia, ou noutras áreas da medicina, em modelos animais vivos e sencientes, em prol do benefício humano, deve ser objecto de planeamento cuidado e ponderado, dado o conflito ético que se coloca. Compete-nos a nós, enquanto investigadores, garantir que as condições de vida, saúde e bem-estar são asseguradas. O uso de ovinos como modelo superior pré-clínico, para investigação em Ortopedia, tem-se evidenciado devido às suas caracterís...

  18. Superior vena cava syndrome in hemodialysis patient

    Directory of Open Access Journals (Sweden)

    Azeb Molhem

    2011-01-01

    Full Text Available Obstruction of blood flow in the superior vena cava (SVC results in symptoms and signs of SVC syndrome. SVC obstruction can be caused either by invasion or external compression of the SVC by contagious pathologic processes involving the right lung, lymph nodes, and other mediastinal structures, or by thrombosis of blood within the SVC. Occasionally, both mechanisms co-exist. We hereby report a case of a 28-year-old male, Saudi patient who was diagnosed with end-stage renal disease and was maintained on regular hemodiaysis via right jugular vein dual lumen catheter for ten months. Three years later, the patient presented with signs and symptoms suggestive of SVC obstruction that was successfully managed with SVC stenting.

  19. [Surgical treatment of superior thoracic outlet syndrome].

    Science.gov (United States)

    Gaibov, A D; Kakhorov, A Z; Sadriev, O N; Yunusov, Kh A

    2015-01-01

    The authors present immediate and long-term results of treatment of 117 patients with superior thoracic outlet syndrome (STOS). There were different reasons for compression of neu- rovascular fascicle in outlet of the thorax. The costaclavicular syndrome was a reason in 48 patients, additional cervical ribs had 36 patients. Skalenus syndrome was noted in 26 cases, rudimentary cervical ribs or hypertrophy of cervical vertebrae C7 had 7 patients. Raynaud's syndrome took place in 19 cases. The required volume of diagnostic procedures and surgical treatment of STOS were determined according to the cause of the syndrome. Differentiated approach to the different forms of STOS was used in relation to dominant symptoms of the disease and reasons for compression of neurovascular fascicle. This allowed getting positive results in majority of patients (90,4%) in long- term period.

  20. ANATOMIC RESEARCH OF SUPERIOR CLUNIAL NERVE TRAUMA

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In order to find the mechanism of superior clunial nerve (SCN) trauma, we dissected and revealed SCN from 12 corpses (24 sides). Combining 100 sides of SCN trauma, we inspected the course of SCN, the relation between SCN and it's neighbour tissues with the situation of SCN when being subjected to force. We found that the following special anatomic characteristics and mechanical elements such as the course of SCN, it's turning angles, the bony fibrous tube at the iliac crest, the posterior layer of the lumbodorsal fascia and SCN neighbour adipose tissue, are the causes of external force inducing SCN trauma. The anatomic revealment is the guidance of SCN trauma treatment with edged needle.

  1. Superiorization: An optimization heuristic for medical physics

    CERN Document Server

    Herman, G T; Davidi, R; Censor, Y

    2012-01-01

    Purpose: To describe and mathematically validate the superiorization methodology, which is a recently-developed heuristic approach to optimization, and to discuss its applicability to medical physics problem formulations that specify the desired solution (of physically given or otherwise obtained constraints) by an optimization criterion. Methods: The underlying idea is that many iterative algorithms for finding such a solution are perturbation resilient in the sense that, even if certain kinds of changes are made at the end of each iterative step, the algorithm still produces a constraints-compatible solution. This property is exploited by using permitted changes to steer the algorithm to a solution that is not only constraints-compatible, but is also desirable according to a specified optimization criterion. The approach is very general, it is applicable to many iterative procedures and optimization criteria used in medical physics. Results: The main practical contribution is a procedure for automatically p...

  2. Authenticated, private, and secured smart cards (APS-SC)

    Science.gov (United States)

    Szu, Harold; Mehmood, Amir

    2006-04-01

    From historical perspective, the recent advancements in better antenna designs, low power circuitry integrations and inexpensive fabrication materials have made possible a miniature counter-measure against Radar, a clutter behaving like a fake target return called Digital Reflection Frequency Modulation (DRFM). Such a military counter-measure have found its way in the commerce as a near field communication known as Radio Frequency Identification (RFID), a passive or active item tag T attached to every readable-writable Smart Card (SC): Passports ID, medical patient ID, biometric ID, driver licenses, book ID, library ID, etc. These avalanche phenomena may be due to the 3 rd Gen phones seeking much more versatile & inexpensive interfaces, than the line-of-sight bar-code optical scan. Despite of the popularity of RFID, the lacking of Authenticity, Privacy and Security (APS) protection restricted somewhat the wide spread commercial, financial, medical, legal, and militarily applications. Conventional APS approach can obfuscate a private passkey K of SC with the tag number T or the reader number R, or both, i.e. only T*K or R*K or both will appear on them, where * denotes an invertible operation, e.g. EXOR, but not limited to it. Then, only the authentic owner, knowing all, can inverse the operation, e.g. EXOR*EXOR= I to find K. However, such an encryption could be easily compromised by a hacker seeking exhaustively by comparison based on those frequently used words. Nevertheless, knowing biological wetware lesson for power of pairs sensors and Radar hardware counter-measure history, we can counter the counter-measure DRFM, instead using one RFID tag per SD, we follow the Nature adopting two ears/tags, e.g. each one holding portions of the ID or simply two different ID's readable only by different modes of the interrogating reader, followed by brain central processor in terms of nonlinear invertible shufflers mixing two ID bits. We prefer to adopt such a hardware

  3. Superior calcium homeostasis of extraocular muscles.

    Science.gov (United States)

    Zeiger, Ulrike; Mitchell, Claire H; Khurana, Tejvir S

    2010-11-01

    Extraocular muscles (EOMs) are a unique group of skeletal muscles with unusual physiological properties such as being able to undergo rapid twitch contractions over extended periods and escape damage in the presence of excess intracellular calcium (Ca(2+)) in Duchenne's muscular dystrophy (DMD). Enhanced Ca(2+) buffering has been proposed as a contributory mechanism to explain these properties; however, the mechanisms are not well understood. We investigated mechanisms modulating Ca(2+) levels in EOM and tibialis anterior (TA) limb muscles. Using Fura-2 based ratiometric Ca(2+) imaging of primary myotubes we found that EOM myotubes reduced elevated Ca(2+) ˜2-fold faster than TA myotubes, demonstrating more efficient Ca(2+) buffering. Quantitative PCR (qPCR) and western blotting revealed higher expression of key components of the Ca(2+) regulation system in EOM, such as the cardiac/slow isoforms sarcoplasmic Ca(2+)-ATPase 2 (Serca2) and calsequestrin 2 (Casq2). Interestingly EOM expressed monomeric rather than multimeric forms of phospholamban (Pln), which was phosphorylated at threonine 17 (Thr17) but not at the serine 16 (Ser16) residue. EOM Pln remained monomeric and unphosphorylated at Ser16 despite protein kinase A (PKA) treatment, suggesting differential signalling and modulation cascades involving Pln-mediated Ca(2+) regulation in EOM. Increased expression of Ca(2+)/SR mRNA, proteins, differential post-translational modification of Pln and superior Ca(2+) buffering is consistent with the improved ability of EOM to handle elevated intracellular Ca(2+) levels. These characteristics provide mechanistic insight for the potential role of superior Ca(2+) buffering in the unusual physiology of EOM and their sparing in DMD.

  4. The management of superior sulcus tumors

    Energy Technology Data Exchange (ETDEWEB)

    Komaki, Ritsuko; Cox, J.D.; Putnam, J.B. Jr [Texas Univ., Houston, TX (United States). Anderson Cancer Center] (and others)

    2001-09-01

    Superior sulcus tumors are a rare type of lung cancer arising in the apex of the lung above the sulcus and cause specific symptoms and signs depending on the location and whether the tumor extends into the surrounding structures. Because of the closeness of critical structures to the tumor (e.g., the subclavian artery for anterior lesions, the brachial plexus for lesions in the middle location, and the sympathetic stellate ganglion causing Horner's syndrome [Pancoast's tumor], the vertebral bodies, nerve foramen, and spinal cord for posterior lesions), superior sulcus tumors were often considered marginally respectable or unresectable. Therefore, for many years, preoperative radiation therapy was considered routine treatment for those tumors. However, with the evolution in our understanding of these tumors and modern imaging techniques such as computerized tomography (CT) and magnetic resonant imaging (MRI) and surgical techniques, there is now considerable debate about the roles and timing of surgical resection, radiation therapy, and chemotherapy in the treatment of patients with these tumors. If mediastinoscopy reveals microscopic mediastinal lymph node involvement, the patient can be treated with preoperative concurrent chemoradiotherapy followed by surgery. If there was a gross mediastinal lymph node involvement (N2) on CT, N3 or T4 lesions, the patient can be treated with concurrent chemoradiotherapy with a curative intent; the outcome of such treatment appears to be better than that of sequential chemotherapy followed by radiation therapy. Whenever possible, without compromising the patient's quality of life, surgery should be considered to improve outcome. (author)

  5. STEREO Superior Solar Conjunction Mission Phase

    Science.gov (United States)

    Ossing, Daniel A.; Wilson, Daniel; Balon, Kevin; Hunt, Jack; Dudley, Owen; Chiu, George; Coulter, Timothy; Reese, Angel; Cox, Matthew; Srinivasan, Dipak; hide

    2017-01-01

    With its long duration and high gain antenna (HGA) feed thermal constraint; the NASA Solar-TErestrial RElations Observatory (STEREO) solar conjunction mission phase is quite unique to deep space operations. Originally designed for a two year heliocentric orbit mission to primarily study coronal mass ejection propagation, after 8 years of continuous science data collection, the twin STEREO observatories entered the solar conjunction mission phase, for which they were not designed. Nine months before entering conjunction, an unforeseen thermal constraint threatened to stop daily communications and science data collection for 15months. With a 3.5 month long communication blackout from the superior solar conjunction, without ground commands, each observatory will reset every 3 days, resulting in 35 system resets at an Earth range of 2 AU. As the observatories will be conjoined for the first time in 8 years, a unique opportunity for calibrating the same instruments on identical spacecraft will occur. As each observatory has lost redundancy, and with only a limited fidelity hardware simulator, how can the new observatory configuration be adequately and safely tested on each spacecraft? Without ground commands, how would a 3-axis stabilized spacecraft safely manage the ever accumulating system momentum without using propellant for thrusters? Could science data still be collected for the duration of the solar conjunction mission phase? Would the observatories survive? In its second extended mission, operational resources were limited at best. This paper discusses the solutions to the STEREO superior solar conjunction operational challenges, science data impact, testing, mission operations, results, and lessons learned while implementing.

  6. Synthesis and Isolation of the Titanium-Scandium Endohedral Fullerenes-Sc2 TiC@Ih -C80 , Sc2 TiC@D5h -C80 and Sc2 TiC2 @Ih -C80 : Metal Size Tuning of the Ti(IV) /Ti(III) Redox Potentials.

    Science.gov (United States)

    Junghans, Katrin; Ghiassi, Kamran B; Samoylova, Nataliya A; Deng, Qingming; Rosenkranz, Marco; Olmstead, Marilyn M; Balch, Alan L; Popov, Alexey A

    2016-09-05

    The formation of endohedral metallofullerenes (EMFs) in an electric arc is reported for the mixed-metal Sc-Ti system utilizing methane as a reactive gas. Comparison of these results with those from the Sc/CH4 and Ti/CH4 systems as well as syntheses without methane revealed a strong mutual influence of all key components on the product distribution. Whereas a methane atmosphere alone suppresses the formation of empty cage fullerenes, the Ti/CH4 system forms mainly empty cage fullerenes. In contrast, the main fullerene products in the Sc/CH4 system are Sc4 C2 @C80 (the most abundant EMF from this synthesis), Sc3 C2 @C80 , isomers of Sc2 C2 @C82 , and the family Sc2 C2 n (2 n=74, 76, 82, 86, 90, etc.), as well as Sc3 CH@C80 . The Sc-Ti/CH4 system produces the mixed-metal Sc2 TiC@C2 n (2 n=68, 78, 80) and Sc2 TiC2 @C2 n (2 n=80) clusterfullerene families. The molecular structures of the new, transition-metal-containing endohedral fullerenes, Sc2 TiC@Ih -C80 , Sc2 TiC@D5h -C80 , and Sc2 TiC2 @Ih -C80 , were characterized by NMR spectroscopy. The structure of Sc2 TiC@Ih -C80 was also determined by single-crystal X-ray diffraction, which demonstrated the presence of a short Ti=C double bond. Both Sc2 TiC- and Sc2 TiC2 -containing clusterfullerenes have Ti-localized LUMOs. Encapsulation of the redox-active Ti ion inside the fullerene cage enables analysis of the cluster-cage strain in the endohedral fullerenes through electrochemical measurements.

  7. Compuestos perazufrados de platino(II) con ditioéteres y tiolatos fluorados. Estructuras cristalinas de [Pt(SC6F5)2 (p-C6H4FSCH2CH2-p-SC6H4F)], [Pt(p-SC6HF4)...

    OpenAIRE

    Jorge Bautista; Agusti Bertran; Sylvain Bernès; Ubaldo Duran; Hugo Torrens

    2003-01-01

    En este articulo se describen la síntesis y caracterización de los compuestos cis-[PtCl2(RfSCH2CH2SRf)], Rf = C6F5, p-SC6HF4, o-SC6H4F, m-SC6H4F, p-SC6H4F, m-SC6H4(CF3), y las reacciones de estos compuestos con (SC6F5)– y (p-SC6HF4)– que generan cis- [Pt(SC6F5)2(RfSCH2CH2SRf)] y cis-[Pt(p-SC6HF4) 2(RfSCH2CH2 SRf)], Rf = o-SC6H4F, m-SC6H4F, p-SC6H4F, m-SC6H4(CF3). Para estos compuestos, los datos de RMN de 19F obtenidos a diferentes temperaturas, muestran la presencia e interconversion de isóm...

  8. One-neutron knockout from {sup 51-55}Sc

    Energy Technology Data Exchange (ETDEWEB)

    Schwertel, S.; Maierbeck, P.; Gernhaeuser, R.; Bildstein, V.; Boehmer, M.; Eppinger, K.; Faestermann, T.; Friese, J.; Fabbietti, L.; Maier, L.; Winkler, S. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Kruecken, R. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); TRIUMF, Vancouver (Canada); University of British Columbia, Department of Physics and Astronomy, Vancouver (Canada); Kroell, T. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Alvarez-Pol, H.; Benjamim, E.A.; Benlliure, J.; Caamano, M.; Cortina-Gil, D.; Gascon, M.; Kurtukian, T.; Perez, D.; Rodriguez-Tajes, C. [Universidade de Santiago de Compostela, Departamento de Fisica de Particulas, Santiago de Compostela (Spain); Aksouh, F.; Aumann, T.; Behr, K.; Boretzky, K.; Bruenle, A.; Chatillon, A.; Chulkov, L.V.; Geissel, H.; Gerl, J.; Gorska, M.; Kojouharov, I.; Klimkiewicz, A.; Kurz, N.; Nociforo, C.; Schaffner, H.; Simon, H.; Stanoiu, M.; Suemmerer, K.; Weick, H. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Borge, M.J.G.; Pascual-Izarra, C.; Perea, A.; Tengblad, O. [CSIC, Instituto de Estructura de la Materia, Madrid (Spain); Buerger, A. [University of Oslo, SAFE/OCL, Oslo (Norway); CEA, Gif-sur-Yvette (France); Casarejos, E.; Brown, B.A. [University of Vigo, Vigo (Spain); Enders, J.; Schrieder, G. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Hansen, P.G. [Michigan State University, NSCL, East Lansing, Michigan (United States); Jonson, B.; Nyman, G. [Chalmers Tekniska Hoegskola och Goeteborgs Universitet, Experimentell Fysik, Goeteborg (Sweden); Kanungo, R. [TRIUMF, Vancouver (Canada); GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Saint Mary' s University, Halifax (Canada); Kiselev, O. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Johannes Gutenberg Universitaet, Mainz (Germany); Paul Scherrer Institut, Villigen (Switzerland); Larsson, K. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Chalmers Tekniska Hoegskola och Goeteborgs Universitet, Experimentell Fysik, Goeteborg (Sweden); Le Bleis, T. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); IN2P3-CNRS/Universite Louis Pasteur, Institut Pluridisciplinaire Hubert Curien, Strasbourg Cedex 2 (France); Mahata, K. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Paul Scherrer Institut, Villigen (Switzerland); Nilsson, T. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Chalmers Tekniska Hoegskola och Goeteborgs Universitet, Experimentell Fysik, Goeteborg (Sweden); Prochazka, A. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Comenius University, Faculty of Mathematics and Physics, Bratislava (Slovakia); Rossi, D. [Johannes Gutenberg Universitaet, Mainz (Germany); Sitar, B. [Comenius University, Faculty of Mathematics and Physics, Bratislava (Slovakia); Otsuka, T. [University of Tokyo, Hongo, Bunkyo-ku, Department of Physics, Tokyo (Japan); Tostevin, J.A. [University of Surrey, Department of Physics, Faculty of Engineering and Physical Sciences, Guildford (United Kingdom); Rae, W.D.M. [Garsington, Oxfordshire (United Kingdom)

    2012-12-15

    Results are presented from a one-neutron knockout experiment at relativistic energies of {approx} 420 A MeV on {sup 51-55}Sc using the GSI Fragment Separator as a two-stage magnetic spectrometer and the MINIBALL array for gamma-ray detection. Inclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the contributions corresponding to knockout from the {nu}p{sub 1/2}, {nu}p{sub 3/2}, (L = 1) and {nu}f{sub 7/2}, {nu}f{sub 5/2} (L = 3) neutron orbitals. The observed L = 1 and L = 3 contributions are compared with theoretical cross-sections using eikonal knockout theory and spectroscopic factors from shell model calculations using the GXPF1A interaction. The measured inclusive knockout cross-sections generally follow the trends expected theoretically and given by the spectroscopic strength predicted from the shell model calculations. However, the deduced L = 1 cross-sections are generally 30-40% higher while the L = 3 contributions are about a factor of two smaller than predicted. This points to a promotion of neutrons from the {nu}f{sub 7/2} to the {nu}p{sub 3/2} orbital indicating a weakening of the N = 28 shell gap in these nuclei. While this is not predicted for the phenomenological GXPF1A interaction such a weakening is predicted by recent calculations using realistic low-momentum interactions V{sub low} {sub k} obtained by evolving a chiral N3LO nucleon-nucleon potential. (orig.)

  9. Validity evaluation of Sc x Al1-x N material constants based on SAW characteristics

    Science.gov (United States)

    Tang, Gongbin; Han, Tao; Zhang, Qiaozhen; Yamazaki, Kenta; Omori, Tatsuya; Hashimoto, Ken-ya

    2016-11-01

    This paper is aimed at examining the validity of material constants reported for use in surface acoustic wave (SAW) device simulations. First, based on the full set of material constants calculated by first principle, bulk acoustic wave velocities are calculated for Sc x Al1-x N and compared with published experimental results. Then, the effects of the Sc x Al1-x N material constants with different Sc content on acoustic characteristics are calculated and the influence of shear vibrations on SAW characteristics are recognized. Then, a series of SAW devices are fabricated on Sc x Al1-x N film/Si substrate structure with various Cu and ScAlN thicknesses h Cu and h ScAlN, respectively, and measured variations of phase velocity V and effective electromechanical coupling factor K\\text{e}2 with these parameters are compared with the calculation. The fairly well-agreed results indicate a reliable set of Sc x Al1-x N material constants for SAW device simulations.

  10. Production, purification, and characterization of scFv TNF ligand fusion proteins.

    Science.gov (United States)

    Fick, Andrea; Wyzgol, Agnes; Wajant, Harald

    2012-01-01

    Single-chain variable fragments (scFvs) specific for tumor-associated cell surface antigens are the most broadly used reagents to direct therapeutic or diagnostic effector molecules, such as toxins, radioisotopes, and CD3-stimulating scFvs, to tumors. One novel class of effector molecules that can be targeted to tumors by scFvs are ligands of the tumor necrosis factor (TNF) family. Typically, these molecules have apoptosis inducing and/or immune stimulating properties and are therefore highly attractive for cancer treatment. N-terminal fusion of scFvs does not interfere with the receptor binding capabilities of TNF ligands and thus allows the straightforward generation of scFv TNF ligand fusion proteins. We report here a protocol for the purification of eukaryotically produced scFv TNF ligand fusion proteins based on affinity chromatography on anti-Flag agarose and further describe assays for the determination of the targeting index of this type of scFv-targeted proteins.

  11. Differential dynamics of splicing factor SC35 during the cell cycle

    Indian Academy of Sciences (India)

    Kaushlendra Tripathi; Veena K Parnaik

    2008-09-01

    Pre-mRNA splicing factors are enriched in nuclear domains termed interchromatin granule clusters or nuclear speckles. During mitosis, nuclear speckles are disassembled by metaphase and reassembled in telophase in structures termed mitotic interchromatin granules (MIGs). We analysed the dynamics of the splicing factor SC35 in interphase and mitotic cells. In HeLa cells expressing green fluorescent protein (GFP)-SC35, this was localized in speckles during interphase and dispersed in metaphase. In telophase, GFP-SC35 was highly enriched within telophase nuclei and also detected in MIGs. Fluorescence recovery after photobleaching (FRAP) experiments revealed that the mobility of GFP-SC35 was distinct in different mitotic compartments. Interestingly, the mobility of GFP-SC35 was 3-fold higher in the cytoplasm of metaphase cells compared with interphase speckles, the nucleoplasm or MIGs. Treatment of cells with inhibitors of cyclin-dependent kinases (cdks) caused changes in the organization of nuclear compartments such as nuclear speckles and nucleoli, with corresponding changes in the mobility of GFP-SC35 and GFP-fibrillarin. Our results suggest that the dynamics of SC35 are significantly influenced by the organization of the compartment in which it is localized during the cell cycle.

  12. Growth and Holographic Storage Properties of Sc, Fe Co-Doped Lithium Niobate Crystals

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated.The Sc threshold concentration in Fe:LiNbO3 was implied to be about 3%(mole fraction) because O-H vibration absorption peak of Sc (3%):Fe:LiNbO3 was at 3508 cm-1, compared with 3484 cm-1 of crystals with lower Sc doping level.Sc(3%):Fe:LiNbO3 exhibited higher optical damage resistance ability.The threshold intensity (wavelength 488 nm) of Sc (3%):Fe:LiNbO3 was 2.2×102 W·cm-2, two orders of magnitude higher than that of Fe:LiNbO3.Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method.It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2%(mole fraction) among this crystal series.

  13. CERN Technical Training 2004: New Short Courses (SC) on Microsoft Outlook

    CERN Multimedia

    Monique Duval

    2004-01-01

    The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 31.8.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 31.8.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 7.9.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and she...

  14. CERN Technical Training 2004: New Short Courses (SC) on Microsoft Outlook

    CERN Multimedia

    Monique Duval

    2004-01-01

    The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 22.10.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 22.10.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 9.11.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and...

  15. Technical Training: CERN Technical Training 2004 - New Short Courses (SC) on Microsoft Outlook

    CERN Multimedia

    Monique Duval

    2004-01-01

    The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 31.8.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 31.8.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 7.9.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and s...

  16. CERN Technical Training 2004: New Short Courses (SC) on Microsoft Outlook

    CERN Multimedia

    Monique Duval

    2004-01-01

    The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 22.10.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 22.10.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 9.11.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and...

  17. New separation method of no-carrier-added {sup 47}Sc from titanium targets

    Energy Technology Data Exchange (ETDEWEB)

    Bartos, B.; Majkowska, A.; Kasperek, A.; Krajewski, S.; Bilewicz, A. [Institute of Nuclear Chemistry and Technology, Warszawa (Poland). Nuclear Chemistry and Radiochemistry Center

    2012-07-01

    Radionuclides with medium energy beta emission and a several day half-life are attractive candidates for radioimmunotherapy. Among the most promising in this category is {sup 47}Sc produced by fast neutron irradiation (E{sub n} > 1 MeV) of titanium target with high energy neutrons in {sup 47}Ti(n,p){sup 47}Sc nuclear reaction. In the previously reported production scheme the dissolution of the TiO{sub 2} target in hot concentrated H{sub 2}SO{sub 4} and evaporation of the resulting solution were the most time-consuming steps. The present paper describes new, simple and efficient production method of {sup 47}Sc, where the slow dissolution of the target is avoided. After irradiation in fast neutron flux {sup 47}TiO{sub 2} and Li{sub 2}{sup 47}TiF{sub 6} targets were dissolved in HF solutions. Next {sup 47}Sc was separated from the target using anion exchange resin Dowex 1 with 0.4 M HF + 0.06 M HNO{sub 3} solution as eluent. The eluted {sup 47}Sc was adsorbed on cation exchange resin and eluted with 0.5 M of ammonium acetate. The 47Sc separation yield in the proposed procedure is about 90% with the separation time less than 2 h. The obtained no-carrier-added {sup 47}Sc was used to label DOTATATE conjugate with 96% labeling yield. (orig.)

  18. Differential Attack on Five Rounds of the SC2000 Block Cipher

    Institute of Scientific and Technical Information of China (English)

    Ji-Qiang Lv

    2011-01-01

    The SC2000 block cipher has a 128-bit block size and a user key of 128,192 or 256 bits,which employs a total of 6.5 rounds if a 128-bit user key is used.It is a CRYPTREC recommended e-government cipher in Japan.In this paper we address how to recover the user key from a few subkey bits of SC2000,and describe two 4.75-round differential characteristics with probability 2-126 of SC2000 and seventy-six 4.75-round differential characteristics with probability 2-127.Finally,we present a differential cryptanalysis attack on a 5-round reduced version of SC2000 when used with a 128-bit key; the attack requires 2125.68 chosen plaintexts and has a time complexity of 212575 5-round SC2000 encryptions.The attack does not threat the security of the full SC2000 cipher,but it suggests for the first time that the safety margin of SC2000 with a 128-bit key decreases below one and a half rounds.

  19. Chronic Hypoxia Suppresses the Co2 Response of Solitary Complex (Sc) Neurons from Rats

    Science.gov (United States)

    Nichols, Nicole L.; Wilkinson, Katherine A.; Powell, Frank L.; Dean, Jay B.; Putnam, Robert W.

    2009-01-01

    We studied the effect of chronic hypobaric hypoxia (CHx; 10-11% O2) on the response to hypercapnia (15% CO2) of individual solitary complex (SC) neurons from adult rats. We simultaneously measured the intracellular pH and firing rate responses to hypercapnia of SC neurons in superfused medullary slices from control and CHx-adapted adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. We found that CHx caused the percentage of SC neurons inhibited by hypercapnia to significantly increase from about 10% up to about 30%, but did not significantly alter the percentage of SC neurons activated by hypercapnia (50% in control versus 35% in CHx). Further, the magnitudes of the responses of SC neurons from control rats (chemosensitivity index for activated neurons of 166±11% and for inhibited neurons of 45±15%) were the same in SC neurons from CHx-adapted rats. This plasticity induced in chemosensitive SC neurons by CHx appears to involve intrinsic changes in neuronal properties since they were the same in synaptic blockade medium. PMID:19619674

  20. Radiolabeling of DOTATOC with the long-lived positron emitter 44Sc.

    Science.gov (United States)

    Pruszyński, Marek; Majkowska-Pilip, Agnieszka; Loktionova, Natalia S; Eppard, Elisabeth; Roesch, Frank

    2012-06-01

    The positron-emitting radionuclide (44)Sc with a half-life of 3.97 h and a β(+) branching of 94.3% is of potential interest for clinical PET. As so far it is available from a (44)Ti/(44)Sc generator in Mainz, where long-lived (44)Ti decays to no-carrier-added (nca) (44)Sc. The (44)Sc is a trivalent metal cation and should be suitable for complexation with many well established bifunctional chelators conjugated to peptides or other molecular targeting vectors. Thus, the aim of this work was to investigate the potential of (44)Sc for labeling of DOTA-conjugated peptides. DOTA-D-Phe(1)-Tyr(3)-octreotide (DOTATOC) was used as a model molecule to study and optimize labeling procedure. Reaction parameters such as buffer conditions, concentration of peptide, pH range, reaction temperature and time were optimized. Addition of 21 nmol of DOTATOC to (44)Sc in ammonium acetate buffer pH 4.0 provided labeling yields >98% within 25 min of heating in an oil-bath at 95°C. This time can be reduced to 3 min only by applying microwave supported heating. (44)Sc-DOTATOC was found to be stable in 0.9% NaCl, PBS pH 7.4, fetal calf and human serums, and also in the presence of competing metal cations (Fe(3+), Ca(2+), Cu(2+), Mg(2+)), as well as other ligand competitors, like EDTA and DTPA, even after almost 25 h incubation at 37°C. Present study shows that nca (44)Sc forms stable complexes with the macrocyclic ligand DOTA and that (44)Sc-DOTATOC and analog targeting vectors may be synthesized for further preclinical and clinical investigations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Synergistic capture of Clostridium botulinum Type A neurotoxin by scFv antibodies to novel epitopes

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Sean A.; Barr, John R.; Kalb, Suzanne R.; Marks, James D.; Baird, Cheryl L.; Cangelosi, Gerard A.; Miller, Keith D.; Feldhaus, Michael J.

    2011-10-01

    A non-immune library of human single chain fragment variable (scFv) antibodies displayed on Saccharomyces cerevisiae was screened for binding to the Clostridium botulinum neurotoxin serotype A binding domain [BoNT/A (Hc)] with the goal of identifying scFv to novel epitopes. To do this, an antibody-mediated labeling strategy was used in which antigen-binding yeast clones were selected after labeling with previously characterized monoclonal antibodies (MAbs) specific to the Hc. Twenty unique scFv clones were isolated that bound Hc. Of these, three also bound to full-length BoNT/A toxin complex with affinities ranging from 5 nM to 170 nM. Epitope binning showed that the three unique clones recognized at least two epitopes that were distinct from one another and from the detection MAbs. After production in E. coli, the scFv were coupled to magnetic particles and tested for their ability to capture BoNT/A holotoxin using an Endopep-MS assay. In this assay, toxin captured by scFv coated magnetic particles was detected by incubation of the complex with a peptide containing a BoNT/A-specific cleavage sequence. Mass spectrometry was used to detect the ratio of intact peptide to cleavage products as evidence for toxin capture. When tested individually, each of the scFv showed a weak positive Endopep-MS result. However, when the particles were coated with all three scFv simultaneously, they exhibited significantly higher Endopep-MS activity, consistent with synergistic binding. These results demonstrate novel approaches toward the isolation and characterization of scFv antibodies specific to unlabeled antigen. They also provide evidence that distinct scFv antibodies can work synergistically to increase the efficiency of antigen capture onto a solid support.

  2. Flow cytometry-based methods for assessing soluble scFv activities and detecting pathogen antigens in solution

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Sean; Weigel, Kris M.; Miller, Keith D.; Ndung' u, Joseph; Buscher, Philippe; Tran, Thao N.; Baird, Cheryl L.; Cangelosi, Gerard A.

    2010-04-01

    Novel methods are reported for evaluating and utilizing single chain fragment variable (scFv) antibodies derived from yeast-display libraries. Yeast-display was used to select scFv specific to invariant surface glycoproteins (ISG) of Trypanosoma brucei. A limiting step in the isolation of scFv from nonimmune libraries is the conversion of highly active yeast-displayed scFv into soluble antibodies that can be used in standard immunoassays. Challenges include limited solubility or activity following secretion and purification of scFv. For this reason, few scFv derived from yeast-display platforms have moved into development and implementation as diagnostic reagents. To address this problem, assays were developed that employ both yeastdisplayed and secreted scFv as analytical reagents. The first is a competitive inhibition flow cytometry (CIFC) assay that detects secreted scFv by virtue of its ability to competitively inhibit the binding of biotinylated antigen to yeast-displayed scFv. The second is an epitope binning assay that uses secreted scFv toidentify additional yeast-displayed scFv that bind nonoverlapping or noncompeting epitopes on an antigen. The epitope binning assay was used not only to identify sandwich assay pairs with yeast-displayed scFv, but also to identify active soluble scFv present in low concentration in a crude expression extract. Finally, a CIFC assay was developed that bypasses entirely the need for soluble scFv expression, by using yeast displayed scFv to detect unlabeled antigen in samples. These methods will facilitate the continued development and practical implementation of scFv derived from yeast-display libraries.

  3. Promising electron mobility and high thermal conductivity in Sc2CT2 (T = F, OH) MXenes.

    Science.gov (United States)

    Zha, Xian-Hu; Zhou, Jie; Zhou, Yuhong; Huang, Qing; He, Jian; Francisco, Joseph S; Luo, Kan; Du, Shiyu

    2016-03-21

    MXenes, the new 2D transition metal carbides and nitrides, have recently attracted extensive attention due to their diverse applications and excellent performances. However, the thermal and electrical properties of most MXene materials are yet to be studied. In this work, we investigate the electrical and thermal properties of semiconducting Sc2CT2 (T = F, OH) MXenes using first-principles calculations. Both of the Sc2CT2 (T = F, OH) MXenes are determined to show excellent carrier mobilities. The electron mobility in the Sc2CF2 MXene is found to be strongly anisotropic at room temperature, with values of 5.03 × 10(3) and 1.07 × 10(3) cm(2) V(-1) s(-1) in the zigzag and armchair directions, respectively. The predicted electron mobility in the zigzag direction of the Sc2CF2 is nearly four-fold that in the armchair direction of the promising semiconductor phosphorene. In contrast to Sc2CF2, Sc2C(OH)2 presents approximately isotropic electron mobility. The values at room temperature in the zigzag and armchair directions are calculated as 2.06 × 10(3) cm(2) V(-1) s(-1) and 2.19 × 10(3) cm(2) V(-1) s(-1), respectively. In regard to the thermal properties, the thermal conductivities of the Sc2CT2 (T = F, OH) MXenes have been determined. The predicted values are higher than those of most metals and semiconducting low-dimensional materials, such as monolayer MoS2 and phosphorene. In particular, the room-temperature thermal conductivity along the Sc2CF2 armchair direction has been determined to be as high as 472 W m(-1) K(-1) based on a flake length of 5 μm, which is even higher than that of the best traditional conductor silver. The corresponding value in the zigzag direction of Sc2CF2 is calculated to be 178 W m(-1) K(-1). The thermal conductivity in Sc2C(OH)2 is less anisotropic and lower compared to that in Sc2CF2. The room-temperature value in the armchair (zigzag) direction is determined to be 173 W m(-1) K(-1) (107 W m(-1) K(-1)). Based on their excellent

  4. The Fifth Annual Sc2.0 and Synthetic Genomes Conference: Synthetic Genomes in High Gear.

    Science.gov (United States)

    Walker, Roy S K; Cai, Yizhi

    2016-09-16

    The Sc2.0 project is perhaps the largest synthetic biology project in the public domain, and ultimately aims to construct a new version of the humble brewer's yeast, Saccharomyces cerevisiae. Each year, the Sc2.0 consortium gather to discuss progress in this ambitious project and highlight new developments at the forefront of synthetic genome engineering. This viewpoint summarizes some of the key moments of the 2016 conference, including updates on the Sc2.0 project itself, mammalian synthetic biology, DNA assembly automation, HGP-Write and a panel discussion on the social and ethical perspectives of synthetic biology.

  5. Sc-Si normal incidence mirrors for a VUV interval of 35-50 nm

    CERN Document Server

    Uspenskii, Y A; Vinogradov, A V; Fedorenko, A I; Kondratenko, V V; Pershin, Y P; Zubarev, E N; Mrowka, S; Schäfers, F

    2000-01-01

    The Sc/Si multilayers are suggested as high-reflectivity coatings for a VUV interval of 35-50 nm. Fabricated mirrors show the normal incidence reflectivity of 30-50% which is high enough to effectively manipulate the beams of synchrotron radiation and compact discharge and laser-driven X-ray lasers. The obtained values are not, however, limiting for the Sc/Si coatings. Theoretical estimations as well as electron microscopy studies of Sc-Si interfaces indicate a large potential for further raising the reflectivity.

  6. Assembly of a supercrystal (SC) of the CMS endcap electromagnetic calorimeter

    CERN Multimedia

    J. Williams et al., RAL

    2004-01-01

    The first three pictures show the insertion of the first three rows of crystals into the supercrystal SC03 on Jan. 2004 and the completion of the SC endstops. Fig. 4 shows a complete supercrystal and Fig. 5 its components (alveolar, interface plate, housing, optical fibre, insert, crystal and VPT, endstop). A set of 25 inserts is shown in Fig. 6, while Fig. 7 shows housing, interface plates and inserts. Finally, a SC rear view showing the Vacum Phototriode (VPT) wires through the inserts can be seen in Fig. 8. Fig. 9 and 10 show two supercrystals under test on Dee F and R, respectively.

  7. Valence electron structure analysis of refining mecha-nism of Sc and Ti additions on aluminum

    Institute of Scientific and Technical Information of China (English)

    LI PieJie; YE YiCong; HE LiangJu

    2009-01-01

    The mechanism of the difference of refining effect between Sc and Ti adding to aluminum can not be explained substantially with traditional theory. Valence electron structures of AI-Ti and Al-Sc alloys have been studied by using the empirical electron theory of solids and molecules (EET). The covalent bond electron numbers and interfacial electron density differences are calculated. The conclusion is that, in the two alloys, different covalent bond electron numbers of nucleation particles, and different electron densities on the interface between the second phase particles and the matrix, fundamentally lead to the difference of refining effect between Sc and Ti adding to aluminum.

  8. Ionic conductivity of co-doped Sc2O3-ZrO2 ceramics

    DEFF Research Database (Denmark)

    Omar, Shobit; bin Najib, Waqas; Chen, Weiwu

    2012-01-01

    The oxide ionic conductivity of Sc0.18Zr0.82O1.91 doped with 0.5 mol.% of both Yb2O3 and In2O3 is evaluated at various temperatures in air. Among various co-doped compositions, In0.02Sc0.18Zr0.80O1.90 exhibits the highest grain ionic conductivity followed by Yb0.02Sc0.18Zr0.80O1.90 at 500°C. Howe...

  9. AAZTA: an ideal chelating agent for the development of {sup 44}Sc PET imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, Gabor; Szikra, Dezso; Trencsenyi, Gyoergy [Scanomed Ltd., Debrecen (Hungary); University of Debrecen, Medical Imaging Clinic (Hungary); Fekete, Aniko [University of Debrecen, Medical Imaging Clinic (Hungary); Garai, Ildiko [Scanomed Ltd., Debrecen (Hungary); Giani, Arianna M.; Negri, Roberto [Dipartimento di Scienze del Farmaco, Universita del Piemonte Orientale, Novara (Italy); Masciocchi, Norberto [Dipartimento di Scienza e Alta Tecnologia e To.Sca.Lab, Universita degli Studi dell' Insubria, Como (Italy); Maiocchi, Alessandro; Uggeri, Fulvio [Bracco Imaging spa, Bracco Research Centre, Colleretto Giacosa (Italy); Toth, Imre [Department of Inorganic and Analytical Chemistry, University of Debrecen (Hungary); Aime, Silvio [Dipartimento di Biotecnologie Molecolari e Scienze della Salute, Centro di Imaging Molecolare e Preclinico, Universita degli Studi di Torino (Italy); Giovenzana, Giovanni B. [Dipartimento di Scienze del Farmaco, Universita del Piemonte Orientale, Novara (Italy); CAGE Chemicals srl, Novara (Italy); Baranyai, Zsolt [Bracco Imaging spa, Bracco Research Centre, Colleretto Giacosa (Italy); Department of Inorganic and Analytical Chemistry, University of Debrecen (Hungary)

    2017-02-13

    Unprecedented fast and efficient complexation of Sc{sup III} was demonstrated with the chelating agent AAZTA (AAZTA=1,4-bis(carboxymethyl)-6-[bis(carboxymethyl)] amino-6-methylperhydro-1,4-d iazepine) under mild experimental conditions. The robustness of the {sup 44}Sc(AAZTA){sup -} chelate and conjugated biomolecules thereof is further shown by in vivo PET imaging in healthy and tumor mice models. The new results pave the way towards development of efficient Sc-based radiopharmaceuticals using the AAZTA chelator. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Upper boundary of the Pacific plate subducting beneath Hokkaido, Japan, estimated from ScSp phase

    OpenAIRE

    Osada, Kinue; Yoshizawa, Kazunori; YOMOGIDA, Kiyoshi

    2010-01-01

    Three-dimensional geometry of the upper boundary of the Pacific plate subducting beneath Hokkaido, Japan, was obtained using the ScSp phase: the phase converted from ScS (S wave reflected at the core-mantle boundary) to P wave at the plate boundary. Taking the advantage of a dense seismic network, "Hi-net", recently deployed across the Japanese islands, we applied several seismic array analyses to the recorded waveform data for a large nearby deep earthquake, in order to enhance very weak ScS...

  11. Synthesis of Perovskite ScMnO3 under High Temperature and Pressure

    Science.gov (United States)

    Yu, Tian; Gao, Peng; Tyson, Trevor A.

    2012-02-01

    Perovskite type ScMnO3 was synthesized under high temperature and pressure starting with hexagonal ScMnO3. The detail of the structure is examined by synchrotron x-ray diffraction and IR spectroscopy at room temperature. A highly distorted perovskite phase which is similar to the structure of LaMnO3 is identified by XRD Rietveld Refinement. Due to the small Sc ion radius, each Mn site has a distorted MnO6 polyhedron. This work is supported by DOE Grant DE-FG02-07ER46402.

  12. Magnetic properties of Sc{sub x}Ti{sub 1-x}Fe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, M. [Lab. de Cristallographie, CNRS, 38 - Grenoble (France); Deportes, J. [Lab. Louis Neel, CNRS, 38 - Grenoble (France); Ouladdiaf, B. [Institut Laue-Langevin, 38 - Grenoble (France); Sayetat, F. [Lab. de Cristallographie, CNRS, 38 - Grenoble (France)

    1995-02-09

    The magnetic properties and their thermal dependences of Sc{sub 0.1}Ti{sub 0.9}Fe{sub 1.96}, Sc{sub 0.1}Ti{sub 0.9}Fe{sub 2} and Sc{sub 0.1}Ti{sub 0.9}Fe{sub 2.04} are compared with those of TiFe{sub 2}. The substitution changes the iron-iron distances. Consequently, the Fe atoms on the 6h site show in addition to the antiferromagnetic component a small ferromagnetic one, and a weak magnetic moment appears on the 2a site. ((orig.)).

  13. Crystal structure of triple oxides HO/sub 2/ScNbO/sub 7/ and Sm/sub 2/ScTaO/sub 7/

    Energy Technology Data Exchange (ETDEWEB)

    Filip' ev, V.S.; Cherner, Ya.E.; Bunina, O.A.; Seregin, V.F.

    The structure of new Ho/sub 2/Sc NbO/sub 7/ and Sm/sub 2/ScTaO/sub 7/ compounds synthesized by the three-stage roasting at 1100-1350 deg C was investigated. Powdergrams of the synthesized compounds indicated to be like the cubic structure of pyrochlore type. Periods of unit cells were determined by Bragg reflex angles. The dependence of unreliability factor on values of the position parameter of oxygen x atoms was calculated. Data were obtained that indirectly indicated a substantial disorder in the disposition of Ho and Sc atoms over A and B positions. Values of bond lengths and valence angles were presented.

  14. Lanthanide-doped NaScF4 nanoprobes: crystal structure, optical spectroscopy and biodetection

    Science.gov (United States)

    Ai, Yu; Tu, Datao; Zheng, Wei; Liu, Yongsheng; Kong, Jintao; Hu, Ping; Chen, Zhuo; Huang, Mingdong; Chen, Xueyuan

    2013-06-01

    Trivalent lanthanide ions (Ln3+)-doped inorganic nanoparticles (NPs) as potential luminescent bioprobes have been attracting tremendous interest because of their unique upconversion (UC) and downconversion (DC) luminescence properties. NaScF4, as an important host material, has been rarely reported and its crystal structure remains unclear. Herein, based on the single crystal X-ray diffraction, the space group of NaScF4 crystals was determined to be P31 containing multiple sites of Sc3+ with crystallographic site symmetry of C1, which was verified by high-resolution photoluminescence spectroscopy of Eu3+ at low temperature (10 K). Furthermore, monodisperse and size-controllable NaScF4:Ln3+ NPs were synthesized via a facile thermal decomposition method. The biotinylated NaScF4:Er3+/Yb3+ NPs were demonstrated for their applications as a heterogeneous UC luminescence bioprobe to detect avidin with a detection limit of 180 pM. After bioconjugation with amino-terminal fragment (ATF) of urokinase plasminogen activator (uPA), NaScF4:Ln3+ NPs also exhibited specific recognition of cancer cells overexpressed with uPA receptor (uPAR, an important marker of tumor biology and metastasis), showing great potentials in tumor-targeted bioimaging.Trivalent lanthanide ions (Ln3+)-doped inorganic nanoparticles (NPs) as potential luminescent bioprobes have been attracting tremendous interest because of their unique upconversion (UC) and downconversion (DC) luminescence properties. NaScF4, as an important host material, has been rarely reported and its crystal structure remains unclear. Herein, based on the single crystal X-ray diffraction, the space group of NaScF4 crystals was determined to be P31 containing multiple sites of Sc3+ with crystallographic site symmetry of C1, which was verified by high-resolution photoluminescence spectroscopy of Eu3+ at low temperature (10 K). Furthermore, monodisperse and size-controllable NaScF4:Ln3+ NPs were synthesized via a facile thermal

  15. Guest-induced SC-SC transformation within the first K/Cd heterodimetallic triazole complex: a luminescent sensor for high-explosives and cyano molecules.

    Science.gov (United States)

    Wang, Ying; Jia, Wei; Chen, Ran; Zhao, Xiao-Jun; Wang, Zhong-Liang

    2017-01-03

    The first K/Cd heterodimetallic complex {[Cd1.5(TTPE)1.5Cl3K(H2O)3]·3H2O}n (1b) based on triazole has been generated from {[Cd(TTPE)(HCOO)](NO3)·3DMAC·H2O}n (1) during the ion- and solvent-exchange experiment in an irreversible SC-SC transformation. Based on its luminescence properties, we have, for the first time, demonstrated that 1b is a heterodimetallic sensor for detection of high-explosives and cyano molecules.

  16. Cyclotron production of high purity (44m,44)Sc with deuterons from (44)CaCO3 targets.

    Science.gov (United States)

    Alliot, C; Kerdjoudj, R; Michel, N; Haddad, F; Huclier-Markai, S

    2015-06-01

    Due to its longer half-life, (44)Sc (T1/2 = 3.97 h) as a positron emitter can be an interesting alternative to (68)Ga (T1/2 = 67.71 min). It has been already proposed as a PET radionuclide for scouting bone disease and is already available as a (44)Ti/(44)Sc generator. (44)Sc has an isomeric state, (44 m)Sc (T1/2 = 58.6 h), which can be co-produced with (44)Sc and that has been proved to be considered as an in-vivo PET generator (44 m)Sc/(44)Sc. This work presents the production route of (44 m)Sc/(44)Sc generator from (44)Ca(d,2n), its extraction/purification process and the evaluation of its performances. Irradiation was performed in a low activity target station using a deuteron beam of 16 MeV, which favors the number of (44 m)Sc atoms produced simultaneously to (44)Sc. Typical irradiation conditions were 60 min at 0.2 μA producing 44 MBq of (44)Sc with a (44)Sc/(44 m)Sc activity ratio of 50 at end of irradiation. Separations of the radionuclides were performed by means of cation exchange chromatography using a DGA® resin (Triskem). Then, the developed process was applied with bigger targets, and could be used for preclinical studies. The extraction/purification process leads to a radionucleidic purity higher than 99.99% ((43)Sc, (46)Sc, (48)Sc < DL). (44 m)Sc/(44)Sc labeling towards DOTA moiety was performed in order to get an evaluation of the specific activities that could be reached with regard to all metallic impurities from the resulting source. Reaction parameters of radiolabeling were optimized, reaching yields over 95%, and leading to a specific activity of about 10-20 MBq/nmol for DOTA. A recycling process for the enriched (44)Ca target was developed and optimized. The quality of the final batch with regard to radionucleidic purity, specific activity and metal impurities allowed a right away use for further radiopharmaceutical evaluation. This radionucleidic pair of (44 m)Sc/(44)Sc offers a quite interesting PET radionuclide for being further

  17. Formation Processes of Nanocomposite Strengthening Particles in Rapidly Quenched Al-Sc-Zr Alloys

    Directory of Open Access Journals (Sweden)

    A.V. Kotko

    2012-03-01

    Full Text Available Decomposition processes of supersaturated solid solution of aluminium alloys alloyed with Sc and Zr have been studied in the work. The binary hypereutectic Al-Sc alloys, hyperperitectic Al-Zr alloys and ternary Al-Sc-Zr alloys were chosen. Alloys were obtained by the melt-spinning. Melts were quenched from temperatures of Т = 1000 C and Т = 1400 ºC. The study of the structure of rapidly solidifyed binary Al alloys alloyed with Sc and Zr showed that the crystallization of anomalously supersaturated solid solution (Tquen. = 1400 ºC or the crystallization with the formation of "fan" structure (Tquen. = 1000 ºC are possible depending on the quenching temperature of the melt. The decomposition of anomalously supersaturated solid solution is continuous, with the precipitation of nano-sized spherical Al3X (X-Sc, Zr particles of L12-ordered phase which is isomorphous to matrix. It was found that the loss of thermal stability of Al-Sc alloys is due to the loss of coherence of the strengthening Al3Sc phase. In Al-Zr alloys the loss of strength is due to the formation of a stable tetragonal DO23-ordered A13Zr phase. After co-alloying of Al by Sc and Zr a bimodal grained structure was observed for the hypereutectic ternary alloy (Tquen. = 400ºC. Nano-sized grains of 50-60 nm were present on the boundaries of 1-2 µm large-sized grains. TEM shows the formation of nanocomposite Al3Zr/Al3Sc particles. The formation of Al3Zr shell changes the nature of the interfacial fit of the particle with the matrix and slows down the decomposition during the coalescence. Ternary Al-Sc-Zr alloys have significantly higher thermal stability during aging as compared to binary Al-Sc and Al-Zr alloys. Decomposition processes of supersaturated solid solution of aluminium alloys alloyed with Sc and Zr have been studied in the work. The binary hypereutectic Al-Sc alloys, hyperperitectic Al-Zr alloys and ternary Al-Sc-Zr alloys were chosen. Alloys were

  18. Synthesis and properties of Yb:Sc2O3 transparent ceramics

    Institute of Scientific and Technical Information of China (English)

    JIANG Benxue; HU Chen; LI Jiang; KOU Huamin; SHI Yun; LIU Wenbin; PAN Yubai

    2011-01-01

    Yb:Sc2O3 transparent ceramics were fabricated by solid-state reaction and vacuum sintering method.CaO was added as sintering aids by a high energy ball milling.Transparent nearly-fully dense samples were obtained after 1840 ℃ sintering.Using transmitted-light microscope we get the grain sizes are more than 1 00 μm.Using spectrophotometer we get the absorption coefficient centered at 975 nm was 2.65 cm-1.The phosphorescence spectra showed that the line-widths (FWHM) at 975 and 1041 nm were about 4 and 10 nm and the lifetime of Yb ions in Sc2O3 transparent ceramics was about 883 μs.According to the absorption and fluorescence band centers of Yb:Sc2O3 transparent ceramics,the level scheme of Yb3+ ions in Sc2O3 ceramics could be gotten.

  19. DiSC aitab käitumist parandada / Ain Kivesti

    Index Scriptorium Estoniae

    Kivesti, Ain

    2008-01-01

    DiSC testi abil on võimalik saada ülevaade personaalsetest käitumishoiakutest ning vastavalt olukorrale on võimalik harjumuspärast reageerimisstiili radikaalselt muuta. Kommenteerivad Jorma Sarv ja Paavo Pilv

  20. DiSC aitab käitumist parandada / Ain Kivesti

    Index Scriptorium Estoniae

    Kivesti, Ain

    2008-01-01

    DiSC testi abil on võimalik saada ülevaade personaalsetest käitumishoiakutest ning vastavalt olukorrale on võimalik harjumuspärast reageerimisstiili radikaalselt muuta. Kommenteerivad Jorma Sarv ja Paavo Pilv

  1. 76 FR 23331 - Outer Continental Shelf (OCS) Scientific Committee (SC); Announcement of Plenary Session

    Science.gov (United States)

    2011-04-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf (OCS) Scientific Committee (SC); Announcement of Plenary Session AGENCY: Bureau of Ocean Energy Management, Regulation...

  2. 77 FR 4056 - Outer Continental Shelf (OCS) Scientific Committee (SC); Announcement of Plenary Session

    Science.gov (United States)

    2012-01-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Outer Continental Shelf (OCS) Scientific Committee (SC); Announcement of Plenary Session AGENCY: Bureau of Ocean Energy Management (BOEM), Interior. ACTION: Notice...

  3. Lake Superior Coastal Wetland Fish Assemblages and ...

    Science.gov (United States)

    The role of the coastal margin and the watershed context in defining the ecology of even very large lakes is increasingly being recognized and examined. Coastal wetlands are both important contributors to the biodiversity and productivity of large lakes and important mediators of the lake-basin connection. We explored wetland-watershed connections and their relationship to wetland function and condition using data collected from 37 Lake Superior wetlands spanning a substantial geographic and geomorphic gradient. While none of these wetlands are particularly disturbed, there were nevertheless clear relationships between watershed landuse and wetland habitat and biota, and these varied consistently across wetland type categories that reflected the strength of connection to the watershed. For example, water clarity and vegetation structure complexity declined with decreasing percent natural land cover, and these effects were strongest in riverine wetlands (having generally large watersheds and tributary-dominated hydrology) and weakest in lagoon wetlands (having generally small watersheds and lake-dominate hydrology). Fish abundance and species richness both increased with decreasing percent natural land cover while species diversity decreased, and again the effect was strongest in riverine wetlands. Lagoonal wetlands, which lack any substantial tributary, consistently harbored the fewest species of fish and a composition different from the more watershed-lin

  4. Local Impact Simulation of SC Wall Structures using Aircraft Engine Projectile

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Chulhun; Lee, Jungwhee; Lee, Hanjoo [Dankook Univ., Yongin (Korea, Republic of); Jung, Raeyoung; Hyun, Changhun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-05-15

    SC wall structure developed for nuclear power plant buildings consists of plain concrete and two steel plates on both surface of the concrete, while RC structure consists of re bar and concrete. SC structure has higher scabbing resistance than RC structure due to the action of steel plate on the rear side of impact. Therefore SC structure is known as more effective structure from the viewpoint of aircraft crash than RC structure. However, most of the recent researches and experiments about local impact damage deal with RC structures, and the effect of re bar and steel plate is not considered reasonably. Although Walter et al. and Make-work et al. suggested a formula for evaluating perforation depth of steel plate covered RC walls, most of the previous researches about SC structure are focused on perforation and scabbing due to the impact of hard projectile, rather than soft projectile such as an aircraft. In this research a soft projectile, i. e. aircraft engine, is utilized for impact simulation of RC and SC walls. To evaluate local damage of SC wall structures, parametric study with the variables of wall thickness and steel ratio of the cover plate is performed, and the results are compared with those of RC structures. Since scabbing was prevented by the steel plates, penetration mode of damage was observed in SC walls while scabbing damage was occurred in RC walls. It is confirmed that the rear steel plate not only contains concrete debris, but also reduces the internal damage of the concrete walls. Penetration depth of SC walls did not largely vary due to the increasing steel ratio, and similar results to RC walls were observed when the wall thickness is larger than a certain value since the impact resistance of SC wall is mainly governed by the thickness of concrete part. Therefore, it is expected that similar level of impact resistance to RC structure can be produced with the minimum thickness of steel plates of SC structure. According to these results, SC

  5. Magnetic dipole moment of the doubly closed-shell plus one proton nucleus $^{49}$Sc

    CERN Multimedia

    Gaulard, C V; Walters, W; Nishimura, K; Muto, S; Bingham, C R

    It is proposed to measure the magnetic moment of $^{49}$Sc by the Nuclear Magnetic Resonance on Oriented Nuclei (NMR-ON) method using the NICOLE on-line nuclear orientation facility. $^{49}$Sc is the neutron rich, doubly closed-shell, nucleus $^{48}$Ca plus one proton. Results will be used to deduce the effective g-factors in the $^{48}$Ca region with reference to nuclear structure and meson exchange current effects.

  6. Influence of Sc on high temperature strengthening behavior of Ti-6Al-4V alloy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Vacuum arc melting technique was used to prepare Ti-6Al-4V alloy containing Sc (0.3% and 0.5%, mass fraction). The ingots were melted twice by vacuum self-consumable electrode arc furnace. Forging of ingots was started in β-phase region and finished in high (α+β)-phase region. Annealing after forging was performed in low (α+β)-phase region for 30 min. Isothermal high temperature compression tests were conducted using thermal simulation machine under Ar atmosphere at 850 ℃ and 1 000 ℃, and the strain rate were 0.001, 0.01, 0.1 and 1.0 s-1. Optical microscope(OM), scanning electron microscopy(SEM), energy dispersive spectrum(EDS) and transmission electron microscope(TEM) were used to study the microstructure evolution during high temperature deformation. The results show that, the peak stress value of alloys increases with increasing Sc content after deformation at 850 ℃,however, there is no obvious strengthening of Sc when the alloys are deformed at 1 000 ℃. Sc exists as Sc2O3 forms by internal oxidation during forging procedure, only minor Sc solutes in matrix. At 850 ℃, the interaction between dislocation and participated particles and twinning mechanism controls the deformation procedure accompanied recrystallization. At 1 000 ℃, the deformation of alloys containing Sc is mainly controlled by twinning, while the deformation of alloy without Sc is not only controlled by twinning,but also the interaction between dislocation and precipitated particles inside the twinning lamellar.

  7. CMS ECAL Endcap (EE) Dee Assembly - SC mounting on Dee 1

    CERN Document Server

    Cockerill, D

    2007-01-01

    Protection panels on back of Dee 1, Completion of SC mounting, 03/10/2007: Completion of SC mounting (aart from the inner 3-2-1)on the first quadrant of Dee 1 and subsequent survey. 22-28/08/2007: The first supercrystals on Dee1, Dee1 in 867 with the first column of SCs ready for mounting, Dee1 with its protection panels over the laser monitoring fibre system

  8. Early Stages of Precipitation Process in Al-(Mn-)Sc-Zr Alloy Characterized by Positron Annihilation

    KAUST Repository

    Vlach, Martin

    2015-01-29

    Thermal effects on the precipitation stages in as-cast Al-0.70 at. pct Mn-0.15 at. pct Sc-0.05 at. pct Zr alloy were studied. The role of lattice defects was elucidated by positron annihilation spectroscopy (lifetime and coincidence Doppler broadening) enabling investigation of solutes clustering at the atomic scale. This technique has never been used in the Al-Sc- and/or Al-Zr-based alloys so far. Studies by positron annihilation were combined with resistometry, hardness measurements, and microstructure observations. Positrons trapped at defects are preferentially annihilated by Sc electrons. Lifetime of trapped positrons indicates that Sc atoms segregate at dislocations. Maximum fraction of positrons annihilated by Sc electrons occurring at 453 K (180 °C) suggests that clustering of Sc bound with vacancies takes place. It is followed by peak of this fraction at 573 K (300 °C). A rise of the contribution of trapped positrons annihilated by Zr electrons starting at 513 K (240 °C) and attaining maximum also at 573 K (300 °C) confirms that Zr participates in precipitation of the Al3Sc particles already at these temperatures. The pronounced hardening at 573 K (300 °C) has its nature in the precipitation of the Al3Sc particles with a Zr-rich shell. The contribution of trapped positrons annihilated by Mn electrons was found to be negligible. © 2015, The Minerals, Metals & Materials Society and ASM International.

  9. Die 3SC Trendforschung : ein kontinuierliches Programm zur Beobachtung des soziokulturellen Wandels von Sinus Sociovision

    OpenAIRE

    Appel, Cornelia

    2003-01-01

    Die 3SC Trendforschung ist neben der Lebensweltforschung und dem daraus hervorgegangenen Modell der Sinus-Milieus ein zentraler Forschungsansatz des Heidelberger Instituts Sinus Sociovision. Sinus Sociovision, Mitglied des ADM (Arbeitskreis Deutscher Markt- und Sozialforschungsinstitute e.V.), ist eines der führenden Institute für angewandte soziokulturelle Forschung in Deutschland. Die 3SC Trendforschung ist eine von drei Säulen des Forschungs- und Beratungsangebotes von Sinus Sociovision. H...

  10. RlSC & DSP Advanced Microprocessor System Design; Sample Projects, Fall 1991

    OpenAIRE

    Fredine, John E.; Goeckel, Dennis L.; Meyer, David G.; Sailer, Stuart E.; Schmottlach, Glenn E.

    1992-01-01

    RlSC & DSP Microprocessor System Design (EE 595M) provides students with an overview of reduced instruction set (RISC) microprocessors and digital signal processing (DSP) microprocessors, with emphasis on incorporating these devices in general purpose and embedded system designs, respectively. The first half of the course emphasizes design considerations for RlSC microprocessor based computer systems; a half-semester design project focuses on design principles that could be utilized in a gene...

  11. Binding Activity Difference of Anti-CD20 scFv-Fc Fusion Protein Derived from Variable Domain Exchange

    Institute of Scientific and Technical Information of China (English)

    Shusheng Geng; Beifen Shen; Jiannan Feng; Yan Li; Yingxun Sun; Xin Gu; Ying Huang; Yugang Wang; Xianjiang Kang; Hong Chang

    2006-01-01

    Two novel engineered antibody fragments binding to antigen CD20 were generated by fusing a murine IgM-type anti-CD20 single-chain Fv fragment (scFv) to the human IgG1 CH2 (I.e., Cγ2) and CH3 (I.e., Cγ3) domains with the human IgG1 hinge (I.e. Hγ). Given the relationship between structure and function of protein, the 3-D structures of the two engineered antibody fragments were modeled using computer-aided homology modeling method.Furthermore, the relationship between 3-D conformation and their binding activity was evaluated theoretically.Due to the change of active pocket formed by CDRs, the HL23 (VH-Linker-VL-Hγ-Cγ2-Cγ3) remained its activity because of its preserved conformation, while the binding activity of the LH23 (VL-Linker-VH-Hγ-Cγ2-Cγ3) was impaired severely. Experimental studies by flow cytometry and fluorescence microscopy showed that HL23 possessed significantly superior binding activity to CD20-expressing target cells than LH23. That is to say, the order of variable regions could influence the binding activity of the fusion protein to CD20+ cell lines, which was in accordance with the theoretical results. The study highlights the potential relationship between the antibody binding activity and their 3-D conformation, which appears to be worthwhile in providing direction for future antibody design of recombinant antibody.

  12. Detergents modify proteinase K resistance of PrP Sc in different transmissible spongiform encephalopathies (TSEs).

    Science.gov (United States)

    Breyer, Johanna; Wemheuer, Wiebke M; Wrede, Arne; Graham, Catherine; Benestad, Sylvie L; Brenig, Bertram; Richt, Jürgen A; Schulz-Schaeffer, Walter J

    2012-05-25

    Prion diseases are diagnosed by the detection of their proteinase K-resistant prion protein fragment (PrP(Sc)). Various biochemical protocols use different detergents for the tissue preparation. We found that the resistance of PrP(Sc) against proteinase K may vary strongly with the detergent used. In our study, we investigated the influence of the most commonly used detergents on eight different TSE agents derived from different species and distinct prion disease forms. For a high throughput we used a membrane adsorption assay to detect small amounts of prion aggregates, as well as Western blotting. Tissue lysates were prepared using DOC, SLS, SDS or Triton X-100 in different concentrations and these were digested with various amounts of proteinase K. Detergents are able to enhance or diminish the detectability of PrP(Sc) after proteinase K digestion. Depending on the kind of detergent, its concentration - but also on the host species that developed the TSE and the disease form or prion type - the detectability of PrP(Sc) can be very different. The results obtained here may be helpful during the development or improvement of a PrP(Sc) detection method and they point towards a detergent effect that can be additionally used for decontamination purposes. A plausible explanation for the detergent effects described in this article could be an interaction with the lipids associated with PrP(Sc) that may stabilize the aggregates.

  13. Structures and phase transitions of ScH3 under high pressure

    Institute of Scientific and Technical Information of China (English)

    Kong Bo; Zhou Zhu-Wen; Chen De-Liang; Ling-hu Rong-Feng

    2013-01-01

    The structures and the phase transitions of ScH3 under high pressure are investigated using first-principles calculations.The calculated structural parameters at zero pressure agree well with the available experimental data.With increasing pressure,the transition sequence hcp (GdH3-type)→ C2/m →fcc→hcp (YH3-type)→Cmcm of ScH3 is predicted first; the corresponding transition pressures at 0 K are 23 GPa,25 GPa,348 GPa,and 477 GPa,respectively.The C2/m symmetry structure is a possible candidate but not a good one as the intermediate state from hexagonal to cubic in ScH3.On the other hand,via the analysis of the structures of hexagonal ScH2.9,cubic ScH3,and cubic ScH2,we find that the repulsive interactions of H-H atoms must play an important role in the transition from hexagonal to cubic.

  14. Precise ab initio calculations of the 3d transition-metal clusters: Sc2

    Directory of Open Access Journals (Sweden)

    Ilya G. Kaplan

    2011-06-01

    Full Text Available The ground 5Σu− state of Sc2 was studied by the valence multireference configuration interaction method with single and double excitations plus Davidson correction (MRCISD(+Q at the complete basis set limit. The calculations were made under C2v symmetry restrictions, which allowed us to obtain at the dissociation limit the Sc atoms in different states (in all previous studies of Sc2 the D2h symmetry group was employed. From the Mulliken population analysis and energy calculations follows that in the ground state Sc2 dissociates in one Sc in the ground state and the other in the second excited quartet state, 4Fu. The corrected parameters of the ground potential curve are the following: Re = 5.2 bohr, De = 50.37 kcal/mol, and ωe = 234.5 cm-1. The dissociation energy in respect to the dissociation on two Sc in the ground states was estimated as De = 9.98 kcal/mol.

  15. Corrosion behavior of an Al-6Mg-Sc-Zr alloy

    Institute of Scientific and Technical Information of China (English)

    XU Guangxing; TAO Binwu; LIU Jianhua; LI Songmei

    2005-01-01

    The corrosion behavior of an Al-6Mg-Sc-Zr alloy was studied and compared with that of an Al-6Mg-Zr alloy.The addition of scandium into the Al-6Mg-Zr alloy reduced the susceptibility to exfoliation corrosion. By using the constant load tensile method in a 3.5 wt.% NaCl solution, the resistance to SCC of the Al-6Mg-Sc-Zr alloy was higher than that of the Al-6Mg-Zr alloy. When the specimens were not applied with an anodic current, the Al-6Mg-Sc-Zr alloy was resistance to SCC and no brittle cracking was found on the fracture surface. When an anodic current was applied, the Al-6Mg-Sc-Zr alloy specimens failed as a result of accelerated corrosion rather than SCC. It was believed that the addition of scandium resulted in (Al3Sc, Zr) particles that greatly refmed grains and promoted the formation of homogeneous discontinuous distribution of β-phase in the alloy base, which much contributed to good corrosion resistance of the Al-6Mg-Sc-Zr alloy.

  16. The role of interplanetary shock orientation on SC/SI rise time and geoeffectiveness

    Science.gov (United States)

    Selvakumaran, R.; Veenadhari, B.; Ebihara, Y.; Kumar, Sandeep; Prasad, D. S. V. V. D.

    2017-03-01

    Interplanetary (IP) shocks interact with the Earth's magnetosphere, resulting in compression of the magnetosphere which in turn increases the Earth's magnetic field termed as Sudden commencement/Sudden impulse (SC/SI). Apart from IP shock speed and solar wind dynamic pressure, IP shock orientation angle also plays a major role in deciding the SC rise time. In the present study, the IP shock orientation angle and SC/SI rise time for 179 IP shocks are estimated which occurred during solar cycle 23. More than 50% of the Shock orientations are in the range of 140°-160°. The SC/SI rise time decreases with the increase in the orientation angle and IP shock speed. In this work, the type of IP shocks i.e., Radio loud (RL) and Radio quiet (RQ) are examined in connection with SC/SI rise time. The RL associated IP shock speeds show a better correlation than RQ shocks with SC/SI rise time irrespective of the orientation angle. Magnetic Cloud (MC) associated shocks dominate in producing less rise time when compared to Ejecta (EJ) shocks. Magneto hydrodynamic (MHD) simulations are used for three different IP shock orientation categories to see the importance of orientation angle in determining the geoeffectiveness. Simulations results reveal that shocks hitting parallel to the magnetosphere are more geoeffective as compared to oblique shocks by means of change in magnetic field, pressure and Field Aligned Current (FAC).

  17. Unraveling the Sc(3+) Hydration Geometry: The Strange Case of the Far-Coordinated Water Molecule.

    Science.gov (United States)

    Migliorati, Valentina; D'Angelo, Paola

    2016-07-05

    The hydration structure and dynamics of Sc(3+) in aqueous solution have been investigated using a combined approach based on quantum mechanical (QM) calculations, molecular dynamics (MD) simulations, and extended X-ray absorption fine structure (EXAFS) spectroscopy. An effective Sc-water two-body potential has been generated from QM calculations and then used in the MD simulation of Sc(3+) in water, and the reliability of the entire procedure has been assessed by comparing the theoretical structural results with the EXAFS experimental data. The outstanding outcome of this work is that the Sc(3+) ion forms a well-defined capped square antiprism (SAP) complex in aqueous solution, where the eight water molecules closest to the ion are located at the vertexes of a SAP polyhedron, while the ninth water molecule occupying the capping position is unusually found at a very long distance from the ion. This far-coordinated water molecule possesses a degree of structure comparable with the other first shell molecules surrounding the ion at much shorter distances, and its presence gave us the unique opportunity to easily identify the geometry of the Sc(3+) coordination polyhedron. Despite very strong ion-water interactions, the Sc(3+) hydration shell is very labile, as the far-coordinated ligand allows first shell water molecules to easily exchange their positions both inside the solvation shell and with the rest of the solvent molecules.

  18. Improved electrical mobility in highly epitaxial La:BaSnO{sub 3} films on SmScO{sub 3}(110) substrates

    Energy Technology Data Exchange (ETDEWEB)

    Wadekar, P. V.; O' Sullivan, M.; Flack, N. L. O.; Manning, T. D.; Claridge, J. B.; Rosseinsky, M. J. [Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD (United Kingdom); Alaria, J.; Phillips, L. J.; Durose, K. [Stephenson Institute for Renewable Energy and Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Lozano, O.; Lucas, S. [Research Centre for the Physics of Matter and Radiation, Namur Research Institute for Life Sciences, University of Namur, Namur 500 (Belgium)

    2014-08-04

    Heteroepitaxial growth of BaSnO{sub 3} and Ba{sub 1−x}La{sub x}SnO{sub 3} (x = 7%) lanthanum doped barium stannate thin films on different perovskite single crystal (SrTiO{sub 3} (001) and SmScO{sub 3} (110)) substrates has been achieved by pulsed laser deposition under optimized deposition conditions. X-ray diffraction measurements indicate that the films on either of these substrates are relaxed due to the large mismatch and present a high degree of crystallinity with narrow rocking curves and smooth surface morphology while analytical quantification by proton induced X-ray emission confirms the stoichiometric La transfer from a polyphasic target, producing films with measured La contents above the bulk solubility limit. The films show degenerate semiconducting behavior on both substrates, with the observed room temperature resistivities, Hall mobilities, and carrier concentrations of 4.4 mΩ cm, 10.11 cm{sup 2} V{sup −1} s{sup −1}, and 1.38 × 10{sup 20} cm{sup −3} on SmScO{sub 3} and 7.8 mΩ cm, 5.8 cm{sup 2} V{sup −1} s{sup −1}, and 1.36 × 10{sup 20} cm{sup −3} on SrTiO{sub 3} ruling out any extrinsic contribution from the substrate. The superior electrical properties observed on the SmScO{sub 3} substrate are attributed to reduction in dislocation density from the lower lattice mismatch.

  19. Report of AAPM Therapy Physics Committee Task Group 74: in-air output ratio, Sc, for megavoltage photon beams.

    Science.gov (United States)

    Zhu, Timothy C; Ahnesjö, Anders; Lam, Kwok Leung; Li, X Allen; Ma, Chang-Ming Charlie; Palta, Jatinder R; Sharpe, Michael B; Thomadsen, Bruce; Tailor, Ramesh C

    2009-11-01

    The concept of in-air output ratio (Sc) was introduced to characterize how the incident photon fluence per monitor unit (or unit time for a Co-60 unit) varies with collimator settings. However, there has been much confusion regarding the measurement technique to be used that has prevented the accurate and consistent determination of Sc. The main thrust of the report is to devise a theoretical and measurement formalism that ensures interinstitutional consistency of Sc. The in-air output ratio, Sc, is defined as the ratio of primary collision water kerma in free-space, Kp, per monitor unit between an arbitrary collimator setting and the reference collimator setting at the same location. Miniphantoms with sufficient lateral and longitudinal thicknesses to eliminate electron contamination and maintain transient electron equilibrium are recommended for the measurement of Sc. The authors present a correction formalism to extrapolate the correct Sc from the measured values using high-Z miniphantom. Miniphantoms made of high-Z material are used to measure Sc for small fields (e.g., IMRT or stereotactic radiosurgery). This report presents a review of the components of Sc, including headscatter, source-obscuring, and monitor-backscattering effects. A review of calculation methods (Monte Carlo and empirical) used to calculate Sc for arbitrary shaped fields is presented. The authors discussed the use of Sc in photon dose calculation algorithms, in particular, monitor unit calculation. Finally, a summary of Sc data (from RPC and other institutions) is included for QA purposes.

  20. Carbon phosphide monolayers with superior carrier mobility

    Science.gov (United States)

    Wang, Gaoxue; Pandey, Ravindra; Karna, Shashi P.

    2016-04-01

    Two dimensional (2D) materials with a finite band gap and high carrier mobility are sought after materials from both fundamental and technological perspectives. In this paper, we present the results based on the particle swarm optimization method and density functional theory which predict three geometrically different phases of the carbon phosphide (CP) monolayer consisting of sp2 hybridized C atoms and sp3 hybridized P atoms in hexagonal networks. Two of the phases, referred to as α-CP and β-CP with puckered or buckled surfaces are semiconducting with highly anisotropic electronic and mechanical properties. More remarkably, they have the lightest electrons and holes among the known 2D semiconductors, yielding superior carrier mobility. The γ-CP has a distorted hexagonal network and exhibits a semi-metallic behavior with Dirac cones. These theoretical findings suggest that the binary CP monolayer is a yet unexplored 2D material holding great promise for applications in high-performance electronics and optoelectronics.Two dimensional (2D) materials with a finite band gap and high carrier mobility are sought after materials from both fundamental and technological perspectives. In this paper, we present the results based on the particle swarm optimization method and density functional theory which predict three geometrically different phases of the carbon phosphide (CP) monolayer consisting of sp2 hybridized C atoms and sp3 hybridized P atoms in hexagonal networks. Two of the phases, referred to as α-CP and β-CP with puckered or buckled surfaces are semiconducting with highly anisotropic electronic and mechanical properties. More remarkably, they have the lightest electrons and holes among the known 2D semiconductors, yielding superior carrier mobility. The γ-CP has a distorted hexagonal network and exhibits a semi-metallic behavior with Dirac cones. These theoretical findings suggest that the binary CP monolayer is a yet unexplored 2D material holding great

  1. Absent right superior caval vein in situs solitus

    DEFF Research Database (Denmark)

    Lytzen, Rebekka; Sundberg, Karin; Vejlstrup, Niels

    2015-01-01

    no postnatal complications. All children were found to have healthy hearts at follow-up. CONCLUSIONS: In all cases, the findings proved to be a benign condition with no clinical manifestations or complications. Although isolated absent right superior caval vein does not seem to affect the outcome, associated......Introduction In up to 0.07% of the general population, the right anterior cardinal vein obliterates and the left remains open, creating an absent right superior caval vein and a persistent left superior caval vein. Absent right superior caval vein is associated with additional congenital heart...... disease in about half the patients. We wished to study the consequences of absent right superior caval vein as an incidental finding on prenatal ultrasonic malformation screening. Material and methods This is a retrospective case series study of all foetuses diagnosed with absent right superior caval vein...

  2. The Business Value of Superior Energy Performance

    Energy Technology Data Exchange (ETDEWEB)

    McKane, Aimee; Scheihing, Paul; Evans, Tracy; Glatt, Sandy; Meffert, William

    2015-08-04

    Industrial facilities participating in the U.S. Department of Energy’s (US DOE) Superior Energy Performance (SEP) program are finding that it provides them with significant business value. This value starts with the implementation of ISO 50001-Energy management system standard, which provides an internationally-relevant framework for integration of energy management into an organization’s business processes. The resulting structure emphasizes effective use of available data and supports continual improvement of energy performance. International relevance is particularly important for companies with a global presence or trading interests, providing them with access to supporting ISO standards and a growing body of certified companies representing the collective knowledge of communities of practice. This paper examines the business value of SEP, a voluntary program that builds on ISO 50001, inviting industry to demonstrate an even greater commitment through third-party verification of energy performance improvement to a specified level of achievement. Information from 28 facilities that have already achieved SEP certification will illustrate key findings concerning both the value and the challenges from SEP/ISO 50001 implementation. These include the facilities’ experience with implementation, internal and external value of third-party verification of energy performance improvement; attractive payback periods and the importance of SEP tools and guidance. US DOE is working to bring the program to scale, including the Enterprise-Wide Accelerator (SEP for multiple facilities in a company), the Ratepayer-Funded Program Accelerator (supporting tools for utilities and program administrators to include SEP in their program offerings), and expansion of the program to other sectors and industry supply chains.

  3. Coronary artery bypass and superior vena cava syndrome.

    OpenAIRE

    Thomas, T V; Masrani, K; Thomas, J.L.

    1999-01-01

    Superior vena cava syndrome is the obstruction of the superior vena cava or its main tributaries by benign or malignant lesions. The syndrome causes edema and engorgement of the vessels on the face, neck, and arms, nonproductive cough, and dyspnea. We discuss the case of a 48-year-old obese diabetic woman who was admitted with unstable angina. She had previously been diagnosed with superior vena cava syndrome. Urgent coronary artery bypass grafting was necessary Although thousands of coronary...

  4. Superiorization of incremental optimization algorithms for statistical tomographic image reconstruction

    Science.gov (United States)

    Helou, E. S.; Zibetti, M. V. W.; Miqueles, E. X.

    2017-04-01

    We propose the superiorization of incremental algorithms for tomographic image reconstruction. The resulting methods follow a better path in its way to finding the optimal solution for the maximum likelihood problem in the sense that they are closer to the Pareto optimal curve than the non-superiorized techniques. A new scaled gradient iteration is proposed and three superiorization schemes are evaluated. Theoretical analysis of the methods as well as computational experiments with both synthetic and real data are provided.

  5. 77 FR 48856 - Safety Zone; Superior Bay, Duluth, MN

    Science.gov (United States)

    2012-08-15

    ... spectators during the Superior Man Triathlon. DATES: This rule is effective from 6 a.m. to 8:30 a.m. on... Triathlon, which are discussed further below. Under 5 U.S.C. 553(d)(3), the Coast Guard finds that good... inaugural Superior Man Triathlon will occur along the Bay of Lake Superior. The 1.2 mile swim leg of...

  6. Two-gap superconductivity in R2Fe3Si5 (R=Lu, Sc and Sc5Ir4Si10

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Tamegai, Yasuyuki Nakajima, Tsuyoshi Nakagawa, Guoji Li and Hisatomo Harima

    2008-01-01

    Full Text Available R2Fe3Si5 (R= Sc, Y, Lu contains nonmagnetic iron and has a relatively high superconducting transition temperature Tc among iron-containing superconductors. An anomalous temperature dependence of specific heat C(T has been reported for polycrystalline samples down to 1 K. We have grown R2Fe3Si5 single crystals, confirmed the anomalous C(T dependence, and found a second drop in specific heat below 1 K. In Lu2Fe3Si5, we can reproduce C(T below Tc, assuming two distinct energy gaps 2Δ 1/kBTc = 4.4 and 2Δ 2/kBTc = 1.1, with nearly equal weights, indicating that Lu2Fe3Si5 is a two-gap superconductor similar to MgB2. Hall coefficient measurements and band structure calculation also support the multiband contributions to the normal-state properties. The specific heat in the Sc2Fe3Si5 single crystals also shows the two-gap feature. R5Ir4Si10 (R = Sc, rare earth is also a superconductor where competition between superconductivity and the charge-density wave is known for rare earths but not for Sc. We have performed detailed specific heat measurements on Sc5Ir4Si10 single crystals and found that C(T deviates slightly from the behavior expected for weak-coupling superconductors. C(T for these superconductors can also be reproduced well by assuming two superconducting gaps.

  7. In vivo studies validating multitargeting of prostanoid receptors for achieving superior anti-inflammatory effects.

    Science.gov (United States)

    Woodward, David F; Wang, Jenny W; Ni, Ming; Bauer, Alex; Martos, Jose L; Carling, Robert W; Poloso, Neil J

    2017-01-01

    The purpose of these studies was to test the hypothesis that a selected polypharmacological approach for treating the prostanoid-mediated component of inflammatory diseases would produce a therapeutic effect superior to global inhibition of prostaglandin (PG) biosynthesis by aspirin-like drugs. The compound studied was AGN 211377, which had been previously shown to produce a superior effect on cytokine release from human macrophages compared with cyclooxygenase (COX) inhibitors. AGN 211377 antagonizes prostanoid prostaglandin D2 (DP)1, DP2, prostaglandin E2 (EP)1, EP4, prostaglandin F2α, and thromboxane A2 receptors but not anti-inflammatory EP2, prostaglandin I2, or EP3 receptors. Established rodent models of ocular inflammatory diseases were used to determine therapeutic effects in living animals. The drugs were administered systemically after predetermination of their blood levels to ensure bioavailability at an appropriate dose level. Whereas compounds selective for a single prostanoid receptor typically exhibited modest but statistically significant inhibition, AGN 211377 profoundly inhibited S-antigen-induced uveitis and laser-induced retinal neovascularization. Consistent with previous polypharmacological studies on chemokine/cytokine release from human macrophages, the prostanoid EP1 receptor played a permissive role in suppressing neovascularization and inflammation in vivo Comparing AGN 211377 with a close structural congener lacking EP1 antagonism (AGN 197727), AGN 197727 was much less active than AGN 211377, but pronounced anti-inflammatory and angiostatic effects were achieved by adding the EP1 antagonist compound (SC-51322) to AGN 197727 in the systemic dosing regimen. Further, AGN 211377 produced superior anti-inflammatory activity compared with the nonsteroidal anti-inflammatory agent ketorolac. These results indicate the value of using a polypharmacological approach in the design of novel therapeutic agents in preference to compounds targeting a

  8. Superior Mesenteric Artery Syndrome: An Infrequent Complication of Scoliosis Surgery

    Directory of Open Access Journals (Sweden)

    Metin Keskin

    2014-01-01

    Full Text Available Superior mesenteric artery syndrome is a rare condition that causes a proximal small intestinal obstruction due to contraction of the angle between the superior mesenteric artery and the aorta. Scoliosis surgery is one of the 15 reasons for superior mesenteric artery syndrome, which can present with acute or chronic manifestations. Although conservative treatment is usually possible, surgical treatment is required in certain cases that cannot be treated using conservative methods. In this paper, we describe a patient who developed superior mesenteric artery syndrome after scoliosis surgery and was treated with duodenojejunostomy due to failure and complications of conservative treatment.

  9. Superior Vena Cava Thrombosis in a Case of Lung Adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Santanu Ghosh

    2013-01-01

    Full Text Available Superior vena cava syndrome is a common presentation of bronchogenic carcinoma. The mechanism of obstruction is by compression of superior vena cava by the bronchogenic tumor itself or enlarged mediastinal lymph nodes. However obstruction due to intravascular thrombosis is extremely uncommon. Here, we report a rare case of a 65-year-old male smoker who presented with superior vena cava syndrome and bilateral pleural and pericardial effusion with thrombotic occlusion of the superior vena cava in adenocarcinoma of the lung. He was given chemotherapy with carboplatin and gemcitabine with anticoagulant therapy.

  10. [Catheter in the superior vena cava for hemodialysis as a last resort in superior hemithorax].

    Science.gov (United States)

    Restrepo Valencia, C A; Buritica Barragán, C M; Arango, A

    2010-01-01

    We report four patients with chronic kidney disease undergoing haemodialysis therapy, which had exhausted conventional venous access (internal jugular, subclavian) and non-conventional access (axillary, innominate) in the upper hemithorax for haemodialysis. This was primarily due to thrombosis of these veins caused by previous catheterisation. These patients did not qualify for peritoneal dialysis. Using the technique recommended by Archundia et al., 4 indwelling catheters were implanted directly in the superior vena cava in each of the patients with subsequent subcutaneous tunneling. The catheters operated correctly and are currently permeable after being used for an average of 19 months.

  11. TSE strain differentiation in mice by immunohistochemical PrP(Sc) profiles and triplex Western blot.

    Science.gov (United States)

    van Keulen, Lucien J M; Langeveld, Jan P M; Dolstra, Corry H; Jacobs, Jorg; Bossers, Alex; van Zijderveld, Fred G

    2015-10-01

    TSE strains are routinely identified by their incubation period and vacuolation profile in the brain after intracerebral inoculation and serial passaging in inbred mouse lines. There are some major drawbacks to this method that are related to the variation in vacuolation that exists in the brains of mice infected with the same TSE strain and to variation between observers and laboratories in scoring vacuolation and determining the final incubation period. We investigated the potential of PrP(Sc) immunohistochemistry and triplex Western blotting as possible alternative methods to differentiate between TSE strains. TSE reference strains ME7, 87A/87V, 22A/22C, 79A/79V and 301C/301V were intracerebrally inoculated in RIII or VM inbred mice that differ in their PrP genotype. Immunohistochemical PrP(Sc) profiles were drawn up by scanning light microscopy both on coronal and sagittal sections. On the basis of the localization of PrP(Sc) in the cerebral cortex, hippocampus, and cerebellar cortex and the overall type of PrP(Sc) staining, all TSE strains could be well differentiated from each other through their typical strain dependent characteristics. In addition, Western blot showed that the combination of glycosylation profile and 12B2 epitope content of PrP(Sc) allowed to distinguish between all reference strains except for ME7 and 22A in VM mice. TSE strains in mice can be identified on the basis of their PrP(Sc) profile alone. The potential to identify TSE strains in ruminants with these PrP(Sc) profiles after a single primary passage in mice will be the topic of future studies. © 2014 British Neuropathological Society.

  12. Enrichment of Sc2O3 and TiO2 from bauxite ore residues.

    Science.gov (United States)

    Deng, Bona; Li, Guanghui; Luo, Jun; Ye, Qing; Liu, Mingxia; Peng, Zhiwei; Jiang, Tao

    2017-06-05

    As a major byproduct generated in the alumina industry, bauxite ore residue is an important reserve of scandium and titanium. In this study, the feasibility and mechanism of enriching Sc2O3 and TiO2 from a non-magnetic material, which was obtained from carbothermal reductive roasting and magnetic separation of bauxite ore residue, were investigated based on a two-step (acidic and alkali) leaching process. It was revealed that approximately 78% SiO2 and 30-40% of CaO, FeO and Al2O3 were removed from a non-magnetic material with 0.0134wt.% Sc2O3 and 7.64wt.% TiO2 by phosphoric acidic leaching, while about 95% Al2O3 and P2O5 were further leached by subsequent sodium hydroxide leaching of the upper-stream leach residue. A Sc2O3-, TiO2- rich material containing 0.044wt.% Sc2O3 and 25.5wt.% TiO2 was obtained, the recovery and the enrichment factor of Sc2O3 and TiO2 were about 85% and 5, respectively. The enrichment of Sc2O3 was attributed to higher pH (>3.3) of phosphoric acid solution than its dissolution pH(0), and the enrichment of TiO2 was mainly associated with the insoluble perovskite (CaTiO3) in the acidic solution at ambient temperature. As Sc2O3 and TiO2 cannot be dissolved in the alkali solution, they were further enriched in the leach residue.

  13. Low Temperature Synthesis and Characterization of AlScMo3O12

    Directory of Open Access Journals (Sweden)

    Rebecca Truitt

    2015-02-01

    Full Text Available Recent interest in low and negative thermal expansion materials has led to significant research on compounds that exhibit this property, much of which has targeted the A2M3O12 family (A = trivalent cation, M = Mo, W. The expansion and phase transition behavior in this family can be tuned through the choice of the metals incorporated into the structure. An undesired phase transition to a monoclinic structure with large positive expansion can be suppressed in some solid solutions by substituting the A-site by a mixture of two cations. One such material, AlScMo3O12, was successfully synthesized using non-hydrolytic sol-gel chemistry. Depending on the reaction conditions, phase separation into Al2Mo3O12 and Sc2Mo3O12 or single-phase AlScMo3O12 could be obtained. Optimized conditions for the reproducible synthesis of stoichiometric, homogeneous AlScMo3O12 were established. High resolution synchrotron diffraction experiments were carried out to confirm whether samples were homogeneous and to estimate the Al:Sc ratio through Rietveld refinement and Vegard’s law. Single-phase samples were found to adopt the orthorhombic Sc2W3O12 structure at 100 to 460 K. In contrast to all previously-reported A2M3O12 compositions, AlScMo3O12 exhibited positive thermal expansion along all unit cell axes instead of contraction along one or two axes, with expansion coefficients (200–460 K of αa = 1.7 × 10−6 K−1, αb = 6.2 × 10−6 K−1, αc = 2.9 × 10−6 K−1 and αV = 10.8 × 10−6 K−1, respectively.

  14. Evaluation of the difficulty of crystallization of organic compounds using the critical supersaturation ratio (Sc)

    Science.gov (United States)

    Nagamatsu, Daiki; Ida, Yasuo; Takiyama, Hiroshi

    2014-11-01

    In the case of solvent selection, supersolubility is an index for improving crystallization behavior. However, supersolubility is affected by kinetic factors such as the cooling rate. An index for suitable solvent selection is needed. The supersaturation ratio (S) is one of the operation design indices of controlling crystallization behavior such as supersolubility. The S at 298 K (S298) of the pharmaceutical compounds theophylline, noscapine, clotrimazole, indomethacin, carbamazepine, naproxene and tolbutamide were measured in ethanol using a polythermal method. If the compound had a large lnS298, the cooling rate strongly affected the temperature of the cloud point in the cooling crystallization method. In order to estimate the crystallization behavior without the cooling rate effect, the critical supersaturation ratio (Sc) was proposed. Sc at 298 K (Sc298) was calculated from dissolution/cloud points at 0 K/min extrapolated from that of several heating/cooling rates to remove the kinetic effects on S. The lnSc298 values of theophylline, noscapine and clotrimazole were estimated in acetonitrile, methyl ethyl ketone, tetrahydrofuran, ethyl acetate, methanol, ethanol and isopropanol. The lnSc298 value of clotrimazole was the largest in all solvents. The results showed that lnSc298 was a simple index which could be used to evaluate the crystallization behavior resulting from the interaction between the solvent and the compound. In conclusion, the proposed lnSc298 should be useful for comparing the difficulty of crystallization which indicates how we should obtain desired crystals within a certain finite time period for development API in the manufacturing field without considering the effect of the heating/cooling rate.

  15. The inhibition of lung cancer cell growth by intracellular immunization with LC-1 ScFv

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A monoclonal antibody, LC-l, recognizing lung cancer associated common antigens was obtained in authors' laboratory. Its single chain Fv fragment (ScFv) named LC-1 ScFv was constructed based on recombinant phage displayed techniques. For expression on cell membrane, LC-1 ScFv was cloned into pDisplay vector, which directed the cloned gene to express as cell membrane bound protein. The resulting plasmid was sequenced and then introduced by the lipofectin method into a lung adenocarcinoma cell line SPC-A-1. G418 resistant cells were obtained by G418 selection. After transfection, LC-1 ScFv expression was observed by Western blot analysis and the expression of cognate antigens was down-regulated as shown in ELISA assay. SPC-A-1-pDisplay-ScFv cells grew in vitro at lower speed than the control intact cells and the cells transfected with vacant vector. Flow cytometry analysis detected a substantial increase in G1 phase and decrease in S phase in population of SPC-A-1-pDisplay-ScFv cells compared to SPC-A-1 and SPC-A1-pDisplay cells. Semi-quantitative RT-PCR analysis showed that c-myc expression was down-regulated in SPC-A-1-pDisplay-ScFv cells. It seems that the antigens recognized by LC-1 may be in some way involved in a growth stimulating pathway and the antibody blocking of the function of the antigens shut down the pathway and thus down-regulate the expression of c-myc and growth of the cells.

  16. Fatal pericardial tamponade after superior vena cava stenting.

    NARCIS (Netherlands)

    Ploegmakers, M.J.M.; Rutten, M.J.C.M.

    2009-01-01

    We discuss a fatal complication of percutaneous superior vena cava (SVC) self-expandable stent placement in a patient with superior vena cava syndrome (SVCS). The SVCS was caused by a malignant mediastinal mass with total occlusion of the SVC. Twenty-four hours after the procedure, the patient died

  17. 33 CFR 117.495 - Superior Oil Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Superior Oil Canal. 117.495 Section 117.495 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.495 Superior Oil Canal. The draw of the S82 bridge, mile 6.3, in Cameron...

  18. [Superior vena cava syndrome--surgical solution--case report].

    Science.gov (United States)

    Galie, N; Vasile, R; Savu, C; Petreanu, C; Grigorie, V; Tabacu, E

    2010-01-01

    The patient of 52-year-old smoker was admitted in emergency with headaches, dyspnea, oedema and cyanosis of the cephalic extremity and of the superior members. This signs and symptoms suggest a superior vena cava sindrom. Thoracic CT scan shows the thrombosis of the superior vena cava and a tumor localized in the Bariety's Lodge of about 30/40 mm witch is around the right lateral wall of the traheea.This tumor is also tangent to the superior the superior vena cava. The patient was operated by total median sternotomy. By this approach we performed a complete excision of the mediastinal tumor mass. After that we effected a longitudinal cavotomy, we took out the endoluminal clot and we sutured the superior vena cava. The histological diagnosis of the mediastinal tumor was adenocarcinoma tubular-papillary moderately differentiated. The evolution post operative period was favorable the superior vena cava sindrom was a complet remission. The thoracic CT scan control after 9 months later didn't show a local relapse and blood flow was normally throw the superior vena cava.

  19. Fatal pericardial tamponade after superior vena cava stenting.

    NARCIS (Netherlands)

    Ploegmakers, M.J.M.; Rutten, M.J.C.M.

    2009-01-01

    We discuss a fatal complication of percutaneous superior vena cava (SVC) self-expandable stent placement in a patient with superior vena cava syndrome (SVCS). The SVCS was caused by a malignant mediastinal mass with total occlusion of the SVC. Twenty-four hours after the procedure, the patient died

  20. Conductivity ageing studies on 1M10ScSZ (M4+=Ce, Hf)

    DEFF Research Database (Denmark)

    Omar, Shobit; Bin Najib, Waqas; Bonanos, Nikolaos

    2011-01-01

    The long-term conductivity stability is tested on zirconia based electrolyte materials for solid oxide fuel cell applications. The ageing studies have been performed on the samples of ZrO2 co-doped with 10mol% of Sc2O3 and 1mol% MO2, where M = Ce or Hf (denoted respectively 1Ce10ScSZ and 1Hf10Sc......SZ) in oxidising and reducing atmospheres, at 600°C for 3000h. At 600°C, these compositions show initial conductivity of around 9–12mS∙cm−1 in air. After 3000h of ageing, no phase transitions are observed in any of the samples. For the first 1000h, the degradation rate is higher than in the subsequent 2000h......; thereafter, conductivity degrades linearly with time for all samples. In air, the loss in the conductivity is lower than in reducing conditions. The 1Ce10ScSZ shows the highest degradation rate of 3.8%/1000h in wet H2/N2 after the first 1000h of ageing. A colour change of the 1Ce10ScSZ sample from white...