WorldWideScience

Sample records for polarization vision pathway

  1. Polarization Imaging and Insect Vision

    Science.gov (United States)

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  2. Thalamic pathways for active vision.

    Science.gov (United States)

    Wurtz, Robert H; McAlonan, Kerry; Cavanaugh, James; Berman, Rebecca A

    2011-04-01

    Active vision requires the integration of information coming from the retina with that generated internally within the brain, especially by saccadic eye movements. Just as visual information reaches cortex via the lateral geniculate nucleus of the thalamus, this internal information reaches the cerebral cortex through other higher-order nuclei of the thalamus. This review summarizes recent work on four of these thalamic nuclei. The first two pathways convey internal information about upcoming saccades (a corollary discharge) and probably contribute to the neuronal mechanisms that underlie stable visual perception. The second two pathways might contribute to the neuronal mechanisms underlying visual spatial attention in cortex and in the thalamus itself. Published by Elsevier Ltd.

  3. Polarization vision in cuttlefish in a concealed communication channel?

    Science.gov (United States)

    Shashar; Rutledge; Cronin

    1996-01-01

    Polarization sensitivity is well documented in marine animals, but its function is not yet well understood. Of the cephalopods, squid and octopus are known to be sensitive to the orientation of polarization of incoming light. This sensitivity arises from the orthogonal orientation of neighboring photoreceptors. Electron microscopical examination of the retina of the cuttlefish Sepia officinalis L. revealed the same orthogonal structure, suggesting that cuttlefish are also sensitive to linearly polarized light. Viewing cuttlefish through an imaging polarized light analyzer revealed a prominent polarization pattern on the arms, around the eyes and on the forehead of the animals. The polarization pattern disappeared when individuals lay camouflaged on the bottom and also during extreme aggression display, attacks on prey, copulation and egg-laying behavior in females. In behavioral experiments, the responses of cuttlefish to their images reflected from a mirror changed when the polarization patterns of the reflected images were distorted. These results suggest that cuttlefish use polarization vision and display for intraspecific recognition and communication.

  4. Genetic dissection reveals two separate retinal substrates for polarization vision in Drosophila.

    Science.gov (United States)

    Wernet, Mathias F; Velez, Mariel M; Clark, Damon A; Baumann-Klausener, Franziska; Brown, Julian R; Klovstad, Martha; Labhart, Thomas; Clandinin, Thomas R

    2012-01-10

    Linearly polarized light originates from atmospheric scattering or surface reflections and is perceived by insects, spiders, cephalopods, crustaceans, and some vertebrates. Thus, the neural basis underlying how this fundamental quality of light is detected is of broad interest. Morphologically unique, polarization-sensitive ommatidia exist in the dorsal periphery of many insect retinas, forming the dorsal rim area (DRA). However, much less is known about the retinal substrates of behavioral responses to polarized reflections. Drosophila exhibits polarotactic behavior, spontaneously aligning with the e-vector of linearly polarized light, when stimuli are presented either dorsally or ventrally. By combining behavioral experiments with genetic dissection and ultrastructural analyses, we show that distinct photoreceptors mediate the two behaviors: inner photoreceptors R7+R8 of DRA ommatidia are necessary and sufficient for dorsal polarotaxis, whereas ventral responses are mediated by combinations of outer and inner photoreceptors, both of which manifest previously unknown features that render them polarization sensitive. Drosophila uses separate retinal pathways for the detection of linearly polarized light emanating from the sky or from shiny surfaces. This work establishes a behavioral paradigm that will enable genetic dissection of the circuits underlying polarization vision. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Polarization imaging enhancement for target vision through haze

    Science.gov (United States)

    Wu, Hai-Ying; Zhang, San-Xi; Li, Jie; LI, Bin; Tang, Zi-li; Liu, Biao; Jia, Wen-Wu

    2016-10-01

    Haze, fog, and smoke are turbid medium in the atmosphere which usually degrade viewing condition of outdoor scenes. The resulted images lose contrast and color fidelity with serious degradation. Due to loss of large detailed information of measured scene, it will usually lead to invalid detection and measurement. The suspended particles in the atmosphere and the scene being measured give rise to polarization changes by their reflection. In the process of reflection, absorption and scattering, the object itself can be determined by its own polarization characteristics. Based on this point, we proposed an approach for target vision through haze. This approach is based on the polarization differences between the scene being measured and the scattering background to move the haze effects. It can realize a great visibility enhancement and enable the scene rendering even if imaged under restricted viewing conditions with low polarization. In this work, the detailed theoretical operation principle is presented. A validating imaging system is established and the corresponding experiment is carried out. We present the experimental results of haze-free image of scene with recovered high contrast. This method also can be used to effectively enhance the imaging performance of any other optical system.

  6. Loss of vision: imaging the visual pathways

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, H.R. [Institute of Neurology, Lysholm Department of Neuroradiology, London (United Kingdom)

    2005-03-01

    This is an overview of diseases presenting with visual impairment, which aims to provide an understanding of the anatomy and pathology of the visual pathways. It discusses the relevant clinical background and neuroimaging findings on CT and standard and advanced MRI of diseases affecting the globe; optic nerve/sheath complex; optic chiasm, tract and radiation; and visual cortex. The overview covers common tumours, trauma, inflammatory and vascular pathology, and conditions such as benign intracranial hypertension and posterior reversible leukoencephalopathy syndrome. (orig.)

  7. Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light

    Science.gov (United States)

    Horváth, Gábor; Majer, József; Horváth, Loránd; Szivák, Ildikó; Kriska, György

    2008-11-01

    Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color of reflected light.

  8. Functional Reflective Polarizer for Augmented Reality and Color Vision Deficiency

    Science.gov (United States)

    2016-03-03

    optics in multilayer polymer mirrors,” Science 287(5462), 2451–2456 (2000). 10. M. Alpern and T. Wake, “Cone pigments in human deutan colour vision...distinguish between more saturated colors. Last but not least, because of the Helmholtz- Kohlrausch (H-K) effect [30, 31], people psychologically

  9. Neural circuit components of the Drosophila OFF motion vision pathway.

    Science.gov (United States)

    Meier, Matthias; Serbe, Etienne; Maisak, Matthew S; Haag, Jürgen; Dickson, Barry J; Borst, Alexander

    2014-02-17

    Detecting the direction of visual motion is an essential task of the early visual system. The Reichardt detector has been proven to be a faithful description of the underlying computation in insects. A series of recent studies addressed the neural implementation of the Reichardt detector in Drosophila revealing the overall layout in parallel ON and OFF channels, its input neurons from the lamina (L1→ON, and L2→OFF), and the respective output neurons to the lobula plate (ON→T4, and OFF→T5). While anatomical studies showed that T4 cells receive input from L1 via Mi1 and Tm3 cells, the neurons connecting L2 to T5 cells have not been identified so far. It is, however, known that L2 contacts, among others, two neurons, called Tm2 and L4, which show a pronounced directionality in their wiring. We characterized the visual response properties of both Tm2 and L4 neurons via Ca(2+) imaging. We found that Tm2 and L4 cells respond with an increase in activity to moving OFF edges in a direction-unselective manner. To investigate their participation in motion vision, we blocked their output while recording from downstream tangential cells in the lobula plate. Silencing of Tm2 and L4 completely abolishes the response to moving OFF edges. Our results demonstrate that both cell types are essential components of the Drosophila OFF motion vision pathway, prior to the computation of directionality in the dendrites of T5 cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. CREB pathway links PGE2 signaling with macrophage polarization.

    Science.gov (United States)

    Luan, Bing; Yoon, Young-Sil; Le Lay, John; Kaestner, Klaus H; Hedrick, Susan; Montminy, Marc

    2015-12-22

    Obesity is thought to promote insulin resistance in part via activation of the innate immune system. Increases in proinflammatory cytokine production by M1 macrophages inhibit insulin signaling in white adipose tissue. In contrast, M2 macrophages have been found to enhance insulin sensitivity in part by reducing adipose tissue inflammation. The paracrine hormone prostaglandin E2 (PGE2) enhances M2 polarization in part through activation of the cAMP pathway, although the underlying mechanism is unclear. Here we show that PGE2 stimulates M2 polarization via the cyclic AMP-responsive element binding (CREB)-mediated induction of Krupple-like factor 4 (KLF4). Targeted disruption of CREB or the cAMP-regulated transcriptional coactivators 2 and 3 (CRTC2/3) in macrophages down-regulated M2 marker gene expression and promoted insulin resistance in the context of high-fat diet feeding. As re-expression of KLF4 rescued M2 marker gene expression in CREB-depleted cells, our results demonstrate the importance of the CREB/CRTC pathway in maintaining insulin sensitivity in white adipose tissue via its effects on the innate immune system.

  11. On the usefulness of 'what' and 'where' pathways in vision.

    Science.gov (United States)

    de Haan, Edward H F; Cowey, Alan

    2011-10-01

    The primate visual brain is classically portrayed as a large number of separate 'maps', each dedicated to the processing of specific visual cues, such as colour, motion or faces and their many features. In order to understand this fractionated architecture, the concept of cortical 'pathways' or 'streams' was introduced. In the currently prevailing view, the different maps are organised hierarchically into two major pathways, one involved in recognition and memory (the ventral stream or 'what' pathway) and the other in the programming of action (the dorsal stream or 'where' pathway). In this review, we question this heuristically influential but potentially misleading linear hierarchical pathway model and argue instead for a 'patchwork' or network model. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Vision on energy transition pathways in horticulture; Visievorming rond energietransitiepaden in de glastuinbouw

    Energy Technology Data Exchange (ETDEWEB)

    Buurma, J.S.; Van der Velden, N.J.A.; Smit, P.X.

    2011-02-15

    While collecting technical data for the 'Energiemonitor van de Nederlandse glastuinbouw' (Energy monitor of the Dutch greenhouse horticulture) the Dutch research institute LEI also asked the informants about their interests, visions and ambitions with regard to the transition pathways of the program 'Kas als Energiebron' (greenhouse as a source of energy). This document shows the motives of the interviewed parties, which collaboration and/or knowledge they seek and which barriers they encounter on the transition pathways [Dutch] Gelijktijdig met het verzamelen van technische gegevens voor de Energiemonitor van de Nederlandse glastuinbouw heeft het LEI de informanten gevraagd naar hun belangen, visies, wensen en ambities rond de transitiepaden van het programma Kas als Energiebron. De nota laat zien wat de drijfveren van de geinterviewde partijen zijn, welke medewerking en/of kennis zij zoeken en welke belemmeringen zij tegenkomen bij de onderscheiden transitiepaden.

  13. Epidermal wound repair is regulated by the planar cell polarity signaling pathway

    Science.gov (United States)

    Caddy, Jacinta; Wilanowski, Tomasz; Darido, Charbel; Dworkin, Sebastian; Ting, Stephen B.; Zhao, Quan; Rank, Gerhard; Auden, Alana; Srivastava, Seema; Papenfuss, Tony A.; Murdoch, Jennifer N.; Humbert, Patrick O.; Boulos, Nidal; Weber, Thomas; Zuo, Jian; Cunningham, John M.; Jane, Stephen M.

    2010-01-01

    SUMMARY The mammalian PCP pathway regulates diverse developmental processes requiring coordinated cellular movement, including neural tube closure and cochlear stereociliary orientation. Here, we show that epidermal wound repair is regulated by PCP signaling. Mice carrying mutant alleles of PCP genes Vangl2, Celsr1, PTK7, and Scrb1, and the transcription factor Grhl3, interact genetically, exhibiting failed wound healing, neural tube defects and disordered cochlear polarity. Using phylogenetic analysis, ChIP, and gene expression in Grhl3−/− mice, we identified RhoGEF19, a homologue of a RhoA activator involved in PCP signaling in Xenopus, as a direct target of GRHL3. Knockdown of Grhl3 or RhoGEF19 in keratinocytes induced defects in actin polymerisation, cellular polarity and wound healing, and re-expression of RhoGEF19 rescued these defects in Grhl3-kd cells. These results define a role for Grhl3 in PCP signaling, and broadly implicate this pathway in epidermal repair. PMID:20643356

  14. Where, When, and How: Are they all sensorimotor? Towards a unified view of the dorsal pathway in vision and audition.

    Science.gov (United States)

    Rauschecker, Josef P

    2018-01-01

    Dual processing streams in sensory systems have been postulated for a long time. Much experimental evidence has been accumulated from behavioral, neuropsychological, electrophysiological, neuroanatomical and neuroimaging work supporting the existence of largely segregated cortical pathways in both vision and audition. More recently, debate has returned to the question of overlap between these pathways and whether there aren't really more than two processing streams. The present piece defends the dual-system view. Focusing on the functions of the dorsal stream in the auditory and language system I try to reconcile the various models of Where, How and When into one coherent concept of sensorimotor integration. This framework incorporates principles of internal models in feedback control systems and is applicable to the visual system as well. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Color vision versus pattern visual evoked potentials in the assessment of subclinical optic pathway involvement in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Fatih C Gundogan

    2013-01-01

    Full Text Available Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P 100 amplitude, P 100 latency in PVEP and total error scores (TES in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7 and 4.1 ± 4.4 years. MS group showed significantly delayed P 100 latency for both checks (P 0.05 for all. 14 MS patients (70% had an increased TESs in FM-100 Hue, 11 (55% MS patients had delayed P 100 latency and 9 (45% had reduced P 100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P 100 latency, and 0.173 for P 100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

  16. VISIONS: Remote Observations of a Spatially-Structured Filamentary Source of Energetic Neutral Atoms near the Polar Cap Boundary During an Auroral Substorm

    Science.gov (United States)

    Collier, Michael R.; Chornay, D.; Clemmons, J.; Keller, J. W.; Klenzing, J.; Kujawski, J.; McLain, J.; Pfaff, R.; Rowland, D.; Zettergren, M.

    2015-01-01

    We report initial results from the VISualizing Ion Outflow via Neutral atom imaging during a Substorm (VISIONS) rocket that flew through and near several regions of enhanced auroral activity and also sensed regions of ion outflow both remotely and directly. The observed neutral atom fluxes were largest at the lower energies and generally higher in the auroral zone than in the polar cap. In this paper, we focus on data from the latter half of the VISIONS trajectory when the rocket traversed the polar cap region. During this period, many of the energetic neutral atom spectra show a peak at 100 electronvolts. Spectra with peaks around 100 electronvolts are also observed in the Electrostatic Ion Analyzer (EIA) data consistent with these ions comprising the source population for the energetic neutral atoms. The EIA observations of this low energy population extend only over a few tens of kilometers. Furthermore, the directionality of the arriving energetic neutral atoms is consistent with either this spatially localized source of energetic ions extending from as low as about 300 kilometers up to above 600 kilometers or a larger source of energetic ions to the southwest.

  17. Curcumin Modulates Macrophage Polarization Through the Inhibition of the Toll-Like Receptor 4 Expression and its Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Yaoyao Zhou

    2015-05-01

    Full Text Available Background: Curcumin, the active ingredient in curcuma rhizomes, has a wide range of therapeutic effects. However, its atheroprotective activity in human acute monocytic leukemia THP-1 cells remains unclear. We investigated the activity and molecular mechanism of action of curcumin in polarized macrophages. Methods: Phorbol myristate acetate (PMA-treated THP-1 cells were differentiated to macrophages, which were further polarized to M1 cells by lipopolysaccharide (LPS; 1 µg/ml and interferon (IFN-γ (20 ng/ml and treated with varying curcumin concentrations. [3H]thymidine (3H-TdR incorporation assays were utilized to measure curcumin-induced growth inhibition. The expression of tumor necrosis factor-a (TNF-a, interleukin (IL-6, and IL-12B (p40 were measured by quantitative real-time polymerase chain reaction (PCR and enzyme-linked immunosorbent assay (ELISA. Macrophage polarization and its mechanism were evaluated by flow cytometry and western blot. Additionally, toll-like receptor 4 (TLR4 small interfering RNA and mitogen-activated protein kinase (MAPK inhibitors were used to further confirm the molecular mechanism of curcumin on macrophage polarization. Results: Curcumin dose-dependently inhibited M1 macrophage polarization and the production of TNF-a, IL-6, and IL-12B (p40. It also decreased TLR4 expression, which regulates M1 macrophage polarization. Furthermore, curcumin significantly inhibited the phosphorylation of ERK, JNK, p38, and nuclear factor (NF-γB. In contrast, SiTLR4 in combination with p-JNK, p-ERK, and p-p38 inhibition reduced the effect of curcumin on polarization. Conclusions: Curcumin can modulate macrophage polarization through TLR4-mediated signaling pathway inhibition, indicating that its effect on macrophage polarization is related to its anti-inflammatory and atheroprotective effects. Our data suggest that curcumin could be used as a therapeutic agent in atherosclerosis.

  18. The history and visions of African American psychology: multiple pathways to place, space, and authority.

    Science.gov (United States)

    Holliday, Bertha Garrett

    2009-10-01

    The author describes the multiple pathways of events and strategies that served to nurture African American psychology in the United States. Special attention is given to strategies for inclusion and empowerment used in 4 psychological professional and scholarly associations: the American Counseling Association, the American Psychological Association, the Association of Black Psychologists, and the Society for Research in Child Development. In addition, the author describes 4 major intellectual traditions that informed not only the strategies of inclusion but also the theoretical, research, and intervention perspectives and other professional and academic efforts of African American psychologists. Those perspectives are the Afrocentric/African-centered tradition derived from longstanding nationalist/Pan-African and culturally centered traditions within African American communities; the social contextual/multidisciplinary research tradition of the University of Chicago School of Social Science; the empirical social science research tradition of the University of Michigan; and the Black scholar/activist tradition of Howard University. This article also presents a chronological timeline of major events in the history of African American psychology. Copyright 2009 APA, all rights reserved.

  19. Federal Employees Health Benefits Program and Federal Employees Dental and Vision Insurance Program: eligibility for Pathway Programs participants. Interim final rule with request for comments.

    Science.gov (United States)

    2014-01-06

    The U.S. Office of Personnel Management (OPM) is issuing an interim final regulation to update the Federal Employees Health Benefits Program (FEHBP) and the Federal Employees Dental and Vision Insurance Program (FEDVIP) regulations to reflect updated election opportunities for participants in the Pathways Programs. The Pathways Programs were created by Executive Order (E.O.) 13562, signed by the President on December 27, 2010, and are designed to enable the Federal Government to compete effectively for students and recent graduates by improving its recruitment efforts through internships and similar programs with Federal agencies. This interim final rule furthers these recruitment and retention efforts by providing health insurance, as well as dental and vision benefits, to eligible program participants and their families.

  20. ErbB receptors and cell polarity: New pathways and paradigms for understanding cell migration and invasion

    International Nuclear Information System (INIS)

    Feigin, Michael E.; Muthuswamy, Senthil K.

    2009-01-01

    The ErbB family of receptor tyrosine kinases is involved in initiation and progression of a number of human cancers, and receptor activation or overexpression correlates with poor patient survival. Research over the past two decades has elucidated the molecular mechanisms underlying ErbB-induced tumorigenesis, which has resulted in the development of effective targeted therapies. ErbB-induced signal transduction cascades regulate a wide variety of cell processes, including cell proliferation, apoptosis, cell polarity, migration and invasion. Within tumors, disruption of these core processes, through cooperative oncogenic lesions, results in aggressive, metastatic disease. This review will focus on the ErbB signaling networks that regulate migration and invasion and identify a potential role for cell polarity pathways during cancer progression

  1. The role of secretory and endocytic pathways in the maintenance of cell polarity.

    Science.gov (United States)

    Ang, Su Fen; Fölsch, Heike

    2012-01-01

    Epithelial cells line virtually every organ cavity in the body and are important for vectorial transport through epithelial monolayers such as nutrient uptake or waste product excretion. Central to these tasks is the establishment of epithelial cell polarity. During organ development, epithelial cells set up two biochemically distinct plasma membrane domains, the apical and the basolateral domain. Targeting of correct constituents to each of these regions is essential for maintaining epithelial cell polarity. Newly synthesized transmembrane proteins destined for the basolateral or apical membrane domain are sorted into separate transport carriers either at the TGN (trans-Golgi network) or in perinuclear REs (recycling endosomes). After initial delivery, transmembrane proteins, such as nutrient receptors, frequently undergo multiple rounds of endocytosis followed by re-sorting in REs. Recent work in epithelial cells highlights the REs as a potent sorting station with different subdomains representing individual targeting zones that facilitate the correct surface delivery of transmembrane proteins.

  2. Induction of murine macrophage M2 polarization by cigarette smoke extract via the JAK2/STAT3 pathway.

    Directory of Open Access Journals (Sweden)

    Fengjiao Yuan

    Full Text Available Cigarette smoking is a major pathogenic factor in lung cancer. Macrophages play an important role in host defense and adaptive immunity. These cells display diverse phenotypes for performing different functions. M2 type macrophages usually exhibit immunosuppressive and tumor-promoting characteristics. Although macrophage polarization toward the M2 phenotype has been observed in the lungs of cigarette smokers, the molecular basis of the process remains unclear. In this study, we evaluated the possible mechanisms for the polarization of mouse macrophages that are induced by cigarette smoking (CS or cigarette smoke extract (CSE. The results showed that exposure to CSE suppressed the production of reactive oxygen species (ROS and nitric oxide (NO and down-regulated the phagocytic ability of Ana-1 cells. The CD163 expressions on the surface of macrophages from different sources were significantly increased in in vivo and in vitro studies. The M1 macrophage cytokines TNF-α, IL-12p40 and enzyme iNOS decreased in the culture supernatant, and their mRNA levels decreased depending on the time and concentration of CSE. In contrast, the M2 phenotype macrophage cytokines IL-10, IL-6, TGF-β1 and TGF-β2 were up-regulated. Moreover, phosphorylation of JAK2 and STAT3 was observed after the Ana-1 cells were treated with CSE. In addition, pretreating the Ana-1 cells with the STAT3 phosphorylation inhibitor WP1066 inhibited the CSE-induced CD163 expression, increased the mRNA level of IL-10 and significantly decreased the mRNA level of IL-12. In conclusion, we demonstrated that the M2 polarization of macrophages induced by CS could be mediated through JAK2/STAT3 pathway activation.

  3. Precise Molecular Sieving Architectures with Janus Pathways for Both Polar and Nonpolar Molecules.

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    Liu, Jiangtao; Hua, Dan; Zhang, Yu; Japip, Susilo; Chung, Tai-Shung

    2018-03-01

    Precise molecular sieving architectures with Janus superhighways are constructed via a molecularly engineered interfacial reaction between cyclodextrin (CD) and trimesoyl chloride (TMC). Interestingly, the CD/TMC nanofilms constructed with both hydrophobic inner cavities and hydrophilic channels exhibit exceptionally high permeances for both polar and nonpolar solvents. The precise molecular sieving functions are determined by the type of CD building blocks and the inner cavities of intrinsic 3D hollow bowls. Positron annihilation spectroscopy (PAS) confirms that a larger inner CD cavity tends to generate a larger free volume and higher microporosity. Based on the rejection ratio of various dyes, the estimated molecular weight cutoff of CD/TMC nanofilms follows the trend of α-CD/TMC (320 Da) sieving membrane with intrinsic microporosity containing tunable pore size and sharp pore-size distribution can effectively discriminate molecules with different 3D sizes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Advanced Glycation End Products Enhance Macrophages Polarization into M1 Phenotype through Activating RAGE/NF-κB Pathway

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    Xian Jin

    2015-01-01

    Full Text Available Atherosclerotic lesions are accelerated in patients with diabetes. M1 (classically activated in contrast to M2 alternatively activated macrophages play key roles in the progression of atherosclerosis. Since advanced glycation end products (AGEs are major pathogenic factors and active inflammation inducers in diabetes mellitus, this study assessed the effects of AGEs on macrophage polarization. The present study showed that AGEs significantly promoted macrophages to express IL-6 and TNF-α. M1 macrophage markers such as iNOS and surface markers including CD11c and CD86 were significantly upregulated while M2 macrophage markers such as Arg1 and CD206 remained unchanged after AGEs stimulation. AGEs significantly increased RAGE expression in macrophages and activated NF-κB pathway, and the aforementioned effects were partly abolished by administration of anti-RAGE antibody or NF-κB inhibitor PDTC. In conclusion, our results suggest that AGEs enhance macrophage differentiation into proinflammatory M1 phenotype at least partly via RAGE/NF-κB pathway activation.

  5. Advanced Glycation End Products Enhance Macrophages Polarization into M1 Phenotype through Activating RAGE/NF-κB Pathway

    Science.gov (United States)

    Jin, Xian; Yao, Tongqing; Zhou, Zhong'e; Zhu, Jian; Zhang, Song; Hu, Wei; Shen, Chengxing

    2015-01-01

    Atherosclerotic lesions are accelerated in patients with diabetes. M1 (classically activated in contrast to M2 alternatively activated) macrophages play key roles in the progression of atherosclerosis. Since advanced glycation end products (AGEs) are major pathogenic factors and active inflammation inducers in diabetes mellitus, this study assessed the effects of AGEs on macrophage polarization. The present study showed that AGEs significantly promoted macrophages to express IL-6 and TNF-α. M1 macrophage markers such as iNOS and surface markers including CD11c and CD86 were significantly upregulated while M2 macrophage markers such as Arg1 and CD206 remained unchanged after AGEs stimulation. AGEs significantly increased RAGE expression in macrophages and activated NF-κB pathway, and the aforementioned effects were partly abolished by administration of anti-RAGE antibody or NF-κB inhibitor PDTC. In conclusion, our results suggest that AGEs enhance macrophage differentiation into proinflammatory M1 phenotype at least partly via RAGE/NF-κB pathway activation. PMID:26114112

  6. Vision Loss, Sudden

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    ... the nerves that carry visual signals from the eye to the brain (the optic nerve and the visual pathways) Light ... of nerve impulses from the back of the eye to the brain will interfere with vision. Legal blindness is defined ...

  7. Rac1 controls epithelial tube length through the apical secretion and polarity pathways

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    Kévin Sollier

    2016-01-01

    Full Text Available The morphometric parameters of epithelial tubes are critical to the physiology and homeostasis of most organs. In addition, many human diseases are associated with tube-size defects. Here, we show that Rac1 limits epithelial tube elongation in the developing fly trachea by promoting Rab5-dependent endocytosis of the apical determinant Crumbs. Rac1 is also involved in a positive feedback loop with the septate junction protein Coracle. Thereby, Rac1 precludes paracellular diffusion and contributes to the septate junction-dependent secretion of the chitin-modifying enzymes Vermiform and Serpentine, which restrict epithelial tube length independently of Crumbs. Thus, Rac1 is a critical component of two important pathways controlling epithelial tube morphogenesis.

  8. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  9. New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation

    Science.gov (United States)

    Irsch, Kristina; Gramatikov, Boris I.; Wu, Yi-Kai; Guyton, David L.

    2014-06-01

    Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach.

  10. ROCK and RHO Playlist for Preimplantation Development: Streaming to HIPPO Pathway and Apicobasal Polarity in the First Cell Differentiation.

    Science.gov (United States)

    Alarcon, Vernadeth B; Marikawa, Yusuke

    2018-01-01

    In placental mammalian development, the first cell differentiation produces two distinct lineages that emerge according to their position within the embryo: the trophectoderm (TE, placenta precursor) differentiates in the surface, while the inner cell mass (ICM, fetal body precursor) forms inside. Here, we discuss how such position-dependent lineage specifications are regulated by the RHOA subfamily of small GTPases and RHO-associated coiled-coil kinases (ROCK). Recent studies in mouse show that activities of RHO/ROCK are required to promote TE differentiation and to concomitantly suppress ICM formation. RHO/ROCK operate through the HIPPO signaling pathway, whose cell position-specific modulation is central to establishing unique gene expression profiles that confer cell fate. In particular, activities of RHO/ROCK are essential in outside cells to promote nuclear localization of transcriptional co-activators YAP/TAZ, the downstream effectors of HIPPO signaling. Nuclear localization of YAP/TAZ depends on the formation of apicobasal polarity in outside cells, which requires activities of RHO/ROCK. We propose models of how RHO/ROCK regulate lineage specification and lay out challenges for future investigations to deepen our understanding of the roles of RHO/ROCK in preimplantation development. Finally, as RHO/ROCK may be inhibited by certain pharmacological agents, we discuss their potential impact on human preimplantation development in relation to fertility preservation in women.

  11. M2-polarized tumor-associated macrophages facilitated migration and epithelial-mesenchymal transition of HCC cells via the TLR4/STAT3 signaling pathway.

    Science.gov (United States)

    Yao, Rong-Rong; Li, Jing-Huan; Zhang, Rui; Chen, Rong-Xin; Wang, Yan-Hong

    2018-01-16

    M2-polarized macrophages are tumor-associated-macrophages (TAMs), which are important contents of tumor-infiltrating immune cells. Toll-like receptor 4 (TLR4) is a molecular biomarker of tumor aggressiveness and poor prognosis. Toll-like receptors (TLRs) have important roles in the immune system and M2-polarized macrophages. However, the effects of TLR4 on M2-polarized macrophages in hepatocellular carcinoma (HCC) are unknown. Here, TLR4 expressed on HCC cells mediates the pro-tumor effects and mechanisms of M2-polarized macrophages. THP-1 cells were induced to differentiate into M2-like macrophages through treatments with IL-4, IL-13, and phorbol myristate acetate (PMA). We used the HCC cell lines SMMC-7721 and MHCC97-H cultured in conditioned medium from M2-like macrophages (M2-CM) to investigate the migration potential of HCC cells and epithelial-mesenchymal transition (EMT)-associated molecular genetics. Signaling pathways that mediated M2-CM-promoted HCC migration were detected using western blotting. HCC cells cultured with M2-CM displayed a fibroblast-like morphology, an increased metastatic capability, and expression of EMT markers. TLR4 expression was markedly increased in M2-CM-treated HCC cells. TLR4 overexpression promoted HCC cell migration, and a TLR4-neutralizing antibody markedly inhibited HCC EMT in cells cultured with M2-CM. Furthermore, the TLR4/(signal transducer and activator of transcription 3 (STAT3) signaling pathway contributed to the effects of M2-CM on HCC cells. Taken together, M2-polarized macrophages facilitated the migration and EMT of HCC cells via the TLR4/STAT3 signaling pathway, suggesting that TLR4 may be a novel therapeutic target. These results improve our understanding of M2-polarized macrophages.

  12. Low Vision

    Science.gov (United States)

    ... Prevalence Rates for Low Vision by Age, and Race/Ethnicity Table for 2010 U.S. Age-Specific Prevalence ... Ethnicity 2010 Prevalence Rates of Low Vision by Race Table for 2010 Prevalence Rates of Low Vision ...

  13. Vision Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The Vision Lab personnel perform research, development, testing and evaluation of eye protection and vision performance. The lab maintains and continues to develop...

  14. Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesis

    Directory of Open Access Journals (Sweden)

    Hafidh Said

    2012-02-01

    Full Text Available Abstract Background Many flowering plants produce bicellular pollen. The two cells of the pollen grain are destined for separate fates in the male gametophyte, which provides a unique opportunity to study genetic interactions that govern guided single-cell polar expansion of the growing pollen tube and the coordinated control of germ cell division and sperm cell fate specification. We applied the Agilent 44 K tobacco gene chip to conduct the first transcriptomic analysis of the tobacco male gametophyte. In addition, we performed a comparative study of the Arabidopsis root-hair trichoblast transcriptome to evaluate genetic factors and common pathways involved in polarized cell-tip expansion. Results Progression of pollen grains from freshly dehisced anthers to pollen tubes 4 h after germination is accompanied with > 5,161 (14.9% gametophyte-specific expressed probes active in at least one of the developmental stages. In contrast, > 18,821 (54.4% probes were preferentially expressed in the sporophyte. Our comparative approach identified a subset of 104 pollen tube-expressed genes that overlap with root-hair trichoblasts. Reverse genetic analysis of selected candidates demonstrated that Cu/Zn superoxide dismutase 1 (CSD1, a WD-40 containing protein (BP130384, and Replication factor C1 (NtRFC1 are among the central regulators of pollen-tube tip growth. Extension of our analysis beyond the second haploid mitosis enabled identification of an opposing-dynamic accumulation of core regulators of cell proliferation and cell fate determinants in accordance with the progression of the germ cell cycle. Conclusions The current study provides a foundation to isolate conserved regulators of cell tip expansion and those that are unique for pollen tube growth to the female gametophyte. A transcriptomic data set is presented as a benchmark for future functional studies using developing pollen as a model. Our results demonstrated previously unknown functions of

  15. Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesis

    Science.gov (United States)

    2012-01-01

    Background Many flowering plants produce bicellular pollen. The two cells of the pollen grain are destined for separate fates in the male gametophyte, which provides a unique opportunity to study genetic interactions that govern guided single-cell polar expansion of the growing pollen tube and the coordinated control of germ cell division and sperm cell fate specification. We applied the Agilent 44 K tobacco gene chip to conduct the first transcriptomic analysis of the tobacco male gametophyte. In addition, we performed a comparative study of the Arabidopsis root-hair trichoblast transcriptome to evaluate genetic factors and common pathways involved in polarized cell-tip expansion. Results Progression of pollen grains from freshly dehisced anthers to pollen tubes 4 h after germination is accompanied with > 5,161 (14.9%) gametophyte-specific expressed probes active in at least one of the developmental stages. In contrast, > 18,821 (54.4%) probes were preferentially expressed in the sporophyte. Our comparative approach identified a subset of 104 pollen tube-expressed genes that overlap with root-hair trichoblasts. Reverse genetic analysis of selected candidates demonstrated that Cu/Zn superoxide dismutase 1 (CSD1), a WD-40 containing protein (BP130384), and Replication factor C1 (NtRFC1) are among the central regulators of pollen-tube tip growth. Extension of our analysis beyond the second haploid mitosis enabled identification of an opposing-dynamic accumulation of core regulators of cell proliferation and cell fate determinants in accordance with the progression of the germ cell cycle. Conclusions The current study provides a foundation to isolate conserved regulators of cell tip expansion and those that are unique for pollen tube growth to the female gametophyte. A transcriptomic data set is presented as a benchmark for future functional studies using developing pollen as a model. Our results demonstrated previously unknown functions of certain genes in pollen

  16. Prolactin/Jak2 directs apical/basal polarization and luminal linage maturation of mammary epithelial cells through regulation of the Erk1/2 pathway

    Directory of Open Access Journals (Sweden)

    Fengming Liu

    2015-09-01

    Full Text Available Tissue development/remodeling requires modulations in both cellular architecture and phenotype. Aberration in these processes leads to tumorigenesis. During the pregnancy/lactation cycle the mammary epithelial cells undergo complex morphological and phenotypic programs resulting in the acquisition of apical/basal (A/B polarization and cellular maturation necessary for proper lactation. Still the hormonal regulations and cellular mechanisms controlling these events are not entirely elucidated. Here we show that prolactin (PRL/Jak2 pathway in mammary epithelial cells uniquely signals to establish A/B polarity as determined by the apical localization of the tight junction protein zona occludens 1 (ZO-1 and the basal/lateral localization of E-cadherin, and the apical trafficking of lipid droplets. As well, our results indicate that this pathway regulates mammary stem cell hierarchy by inducing the differentiation of luminal progenitor (EpCAMhi/CD49fhi cells to mature luminal (EpCAMhi/CD49flow cells. Moreover, our data indicate that PRL/Jak2 coordinates both of these cellular events through limiting the mitogen activated protein kinase (Erk1/2 pathway. Together our findings define a novel unifying mechanism coupling mammary epithelial cell A/B polarization and terminal differentiation.

  17. The Fz-Dsh planar cell polarity pathway induces oriented cell division via Mud/NuMA in Drosophila and zebrafish.

    Science.gov (United States)

    Ségalen, Marion; Johnston, Christopher A; Martin, Charlotte A; Dumortier, Julien G; Prehoda, Kenneth E; David, Nicolas B; Doe, Chris Q; Bellaïche, Yohanns

    2010-11-16

    The Frizzled receptor and Dishevelled effector regulate mitotic spindle orientation in both vertebrates and invertebrates, but how Dishevelled orients the mitotic spindle is unknown. Using the Drosophila S2 cell "induced polarity" system, we find that Dishevelled cortical polarity is sufficient to orient the spindle and that Dishevelled's DEP domain mediates this function. This domain binds a C-terminal domain of Mud (the Drosophila NuMA ortholog), and Mud is required for Dishevelled-mediated spindle orientation. In Drosophila, Frizzled-Dishevelled planar cell polarity (PCP) orients the sensory organ precursor (pI) spindle along the anterior-posterior axis. We show that Dishevelled and Mud colocalize at the posterior cortex of pI, Mud localization at the posterior cortex requires Dsh, and Mud loss-of-function randomizes spindle orientation. During zebrafish gastrulation, the Wnt11-Frizzled-Dishevelled PCP pathway orients spindles along the animal-vegetal axis, and reducing NuMA levels disrupts spindle orientation. Overall, we describe a Frizzled-Dishevelled-NuMA pathway that orients division from Drosophila to vertebrates. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Loss of the Drosophila cell polarity regulator Scribbled promotes epithelial tissue overgrowth and cooperation with oncogenic Ras-Raf through impaired Hippo pathway signaling

    Directory of Open Access Journals (Sweden)

    Grusche Felix A

    2011-09-01

    Full Text Available Abstract Background Epithelial neoplasias are associated with alterations in cell polarity and excessive cell proliferation, yet how these neoplastic properties are related to one another is still poorly understood. The study of Drosophila genes that function as neoplastic tumor suppressors by regulating both of these properties has significant potential to clarify this relationship. Results Here we show in Drosophila that loss of Scribbled (Scrib, a cell polarity regulator and neoplastic tumor suppressor, results in impaired Hippo pathway signaling in the epithelial tissues of both the eye and wing imaginal disc. scrib mutant tissue overgrowth, but not the loss of cell polarity, is dependent upon defective Hippo signaling and can be rescued by knockdown of either the TEAD/TEF family transcription factor Scalloped or the transcriptional coactivator Yorkie in the eye disc, or reducing levels of Yorkie in the wing disc. Furthermore, loss of Scrib sensitizes tissue to transformation by oncogenic Ras-Raf signaling, and Yorkie-Scalloped activity is required to promote this cooperative tumor overgrowth. The inhibition of Hippo signaling in scrib mutant eye disc clones is not dependent upon JNK activity, but can be significantly rescued by reducing aPKC kinase activity, and ectopic aPKC activity is sufficient to impair Hippo signaling in the eye disc, even when JNK signaling is blocked. In contrast, warts mutant overgrowth does not require aPKC activity. Moreover, reducing endogenous levels of aPKC or increasing Scrib or Lethal giant larvae levels does not promote increased Hippo signaling, suggesting that aPKC activity is not normally rate limiting for Hippo pathway activity. Epistasis experiments suggest that Hippo pathway inhibition in scrib mutants occurs, at least in part, downstream or in parallel to both the Expanded and Fat arms of Hippo pathway regulation. Conclusions Loss of Scrib promotes Yorkie/Scalloped-dependent epithelial tissue

  19. Planar polarity pathway and Nance-Horan syndrome-like 1b have essential cell-autonomous functions in neuronal migration.

    Science.gov (United States)

    Walsh, Gregory S; Grant, Paul K; Morgan, John A; Moens, Cecilia B

    2011-07-01

    Components of the planar cell polarity (PCP) pathway are required for the caudal tangential migration of facial branchiomotor (FBM) neurons, but how PCP signaling regulates this migration is not understood. In a forward genetic screen, we identified a new gene, nhsl1b, required for FBM neuron migration. nhsl1b encodes a WAVE-homology domain-containing protein related to human Nance-Horan syndrome (NHS) protein and Drosophila GUK-holder (Gukh), which have been shown to interact with components of the WAVE regulatory complex that controls cytoskeletal dynamics and with the polarity protein Scribble, respectively. Nhsl1b localizes to FBM neuron membrane protrusions and interacts physically and genetically with Scrib to control FBM neuron migration. Using chimeric analysis, we show that FBM neurons have two modes of migration: one involving interactions between the neurons and their planar-polarized environment, and an alternative, collective mode involving interactions between the neurons themselves. We demonstrate that the first mode of migration requires the cell-autonomous functions of Nhsl1b and the PCP components Scrib and Vangl2 in addition to the non-autonomous functions of Scrib and Vangl2, which serve to polarize the epithelial cells in the environment of the migrating neurons. These results define a role for Nhsl1b as a neuronal effector of PCP signaling and indicate that proper FBM neuron migration is directly controlled by PCP signaling between the epithelium and the migrating neurons.

  20. VISION development

    International Nuclear Information System (INIS)

    Hernandez, J.E.; Sherwood, R.J.; Whitman, S.R.

    1994-01-01

    VISION is a flexible and extensible object-oriented programming environment for prototyping computer-vision and pattern-recognition algorithms. This year's effort focused on three major areas: documentation, graphics, and support for new applications

  1. Computational vision

    CERN Document Server

    Wechsler, Harry

    1990-01-01

    The book is suitable for advanced courses in computer vision and image processing. In addition to providing an overall view of computational vision, it contains extensive material on topics that are not usually covered in computer vision texts (including parallel distributed processing and neural networks) and considers many real applications.

  2. Living with vision loss

    Science.gov (United States)

    Diabetes - vision loss; Retinopathy - vision loss; Low vision; Blindness - vision loss ... Low vision is a visual disability. Wearing regular glasses or contacts does not help. People with low vision have ...

  3. Micro Vision

    OpenAIRE

    Ohba, Kohtaro; Ohara, Kenichi

    2007-01-01

    In the field of the micro vision, there are few researches compared with macro environment. However, applying to the study result for macro computer vision technique, you can measure and observe the micro environment. Moreover, based on the effects of micro environment, it is possible to discovery the new theories and new techniques.

  4. Exendin-4 Induces Bone Marrow Stromal Cells Migration Through Bone Marrow-Derived Macrophages Polarization via PKA-STAT3 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2017-12-01

    Full Text Available Background/Aims: The synthesis and degradation processes involved in bone remodeling are critically regulated by osteoblasts and osteoclasts. The GLP-1 receptor agonist Exendin-4 is beneficial for osteoblast differentiation and increases the number of osteoblasts. Methods: We constructed an ovariectomized model to evaluate the impact of Exendin-4 on bone formation in osteoporosis. A macrophage-depleted model was also created to investigate the effect of macrophages on bone formation. Thirty-two female WT C57BL/6 mice (aged 3 months were randomly assigned to a normal control group and four ovariectomized (OVX subgroups: OVX + vehicle group, OVX + Exendin-4 (4.2 µg/kg/day group, OVX + chloride phosphate liposome group and OVX + chloride phosphate liposome + Exendin-4 group. Results: In this study, we found that Exendin-4 not only increased the number of osteoblasts and decreased the number of osteoclasts, but also increased the number of bone marrow stromal cells (BMSCs at the bone surface. Moreover, we found that OVX mice treated with Exendin-4 increased TGF-β1 levels at the bone surface compared with that in OVX mice. Besides, Exendin-4 promoted the polarization of bone marrow-derived macrophages into M2 subtype and increased TGF-β1 secretion by the M2 subtype. Finally, we found that Exendin-4 induced macrophage polarization via the cAMP-PKA-STAT3 signaling pathway. Conclusion: Exendin-4 promotes bone marrow-derived macrophage polarization to the M2 subtype and induces BMSC migration to the bone surface via PKA-STAT3 signaling.

  5. Computational vision

    Science.gov (United States)

    Barrow, H. G.; Tenenbaum, J. M.

    1981-01-01

    The range of fundamental computational principles underlying human vision that equally apply to artificial and natural systems is surveyed. There emerges from research a view of the structuring of vision systems as a sequence of levels of representation, with the initial levels being primarily iconic (edges, regions, gradients) and the highest symbolic (surfaces, objects, scenes). Intermediate levels are constrained by information made available by preceding levels and information required by subsequent levels. In particular, it appears that physical and three-dimensional surface characteristics provide a critical transition from iconic to symbolic representations. A plausible vision system design incorporating these principles is outlined, and its key computational processes are elaborated.

  6. Computer vision

    Science.gov (United States)

    Gennery, D.; Cunningham, R.; Saund, E.; High, J.; Ruoff, C.

    1981-01-01

    The field of computer vision is surveyed and assessed, key research issues are identified, and possibilities for a future vision system are discussed. The problems of descriptions of two and three dimensional worlds are discussed. The representation of such features as texture, edges, curves, and corners are detailed. Recognition methods are described in which cross correlation coefficients are maximized or numerical values for a set of features are measured. Object tracking is discussed in terms of the robust matching algorithms that must be devised. Stereo vision, camera control and calibration, and the hardware and systems architecture are discussed.

  7. Folic Acid Is Able to Polarize the Inflammatory Response in LPS Activated Microglia by Regulating Multiple Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Antonia Cianciulli

    2016-01-01

    Full Text Available We investigated the ability of folic acid to modulate the inflammatory responses of LPS activated BV-2 microglia cells and the signal transduction pathways involved. To this aim, the BV-2 cell line was exposed to LPS as a proinflammatory response inducer, in presence or absence of various concentrations of folic acid. The production of nitric oxide (NO was determined by the Griess test. The levels of tumor necrosis factor-alpha (TNF-α, interleukin-1 beta (IL-1β, and IL-10 were determined by ELISA. Inducible NO synthase (iNOS, nuclear transcription factor-kappa B (NF-κB p65, MAPKs protein, and suppressors of cytokine signaling (SOCS1 and SOCS3 were analyzed by western blotting. TNF-α and IL-1β, as well as iNOS dependent NO production, resulted significantly inhibited by folic acid pretreatment in LPS-activated BV-2 cells. We also observed that folic acid dose-dependently upregulated both SOCS1 and SOCS3 expression in BV-2 cells, leading to an increased expression of the anti-inflammatory cytokine IL-10. Finally, p-IκBα, which indirectly reflects NF-κB complex activation, and JNK phosphorylation resulted dose-dependently downregulated by folic acid pretreatment of LPS-activated cells, whereas p38 MAPK phosphorylation resulted significantly upregulated by folic acid treatment. Overall, these results demonstrated that folic acid was able to modulate the inflammatory response in microglia cells, shifting proinflammatory versus anti-inflammatory responses through regulating multiple signaling pathways.

  8. Early planarian brain regeneration is independent of blastema polarity mediated by the Wnt/β-catenin pathway.

    Science.gov (United States)

    Iglesias, Marta; Almuedo-Castillo, Maria; Aboobaker, A Aziz; Saló, Emili

    2011-10-01

    Analysis of anteroposterior (AP) axis specification in regenerating planarian flatworms has shown that Wnt/β-catenin signaling is required for posterior specification and that the FGF-like receptor molecule nou-darake (ndk) may be involved in restricting brain regeneration to anterior regions. The relationship between re-establishment of AP identity and correct morphogenesis of the brain is, however, still poorly understood. Here we report the characterization of two axin paralogs in the planarian Schmidtea mediterranea. Although Axins are well known negative regulators of Wnt/β-catenin signaling, no role in AP specification has previously been reported for axin genes in planarians. We show that silencing of Smed-axin genes by RNA interference (RNAi) results in two-tailed planarians, a phenotype previously reported after silencing of Smed-APC-1, another β-catenin inhibitor. More strikingly, we show for the first time that while early brain formation at anterior wounds remains unaffected, subsequent development of the brain is blocked in the two-tailed planarians generated after silencing of Smed-axin genes and Smed-APC-1. These findings suggest that the mechanisms underlying early brain formation can be uncoupled from the specification of AP identity by the Wnt/β-catenin pathway. Finally, the posterior expansion of the brain observed following Smed-ndk RNAi is enhanced by silencing Smed-APC-1, revealing an indirect relationship between the FGFR/Ndk and Wnt/β-catenin signaling systems in establishing the posterior limits of brain differentiation. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Industrial vision

    DEFF Research Database (Denmark)

    Knudsen, Ole

    1998-01-01

    This dissertation is concerned with the introduction of vision-based application s in the ship building industry. The industrial research project is divided into a natural seq uence of developments, from basic theoretical projective image generation via CAD and subpixel analysis to a description...... is present ed, and the variability of the parameters is examined and described. The concept of using CAD together with vision information is based on the fact that all items processed at OSS have an associated complete 3D CAD model that is accessible at all production states. This concept gives numerous...... possibilities for using vision in applications which otherwise would be very difficult to automate. The requirement for low tolerances in production is, despite the huge dimensions of the items involved, extreme. This fact makes great demands on the ability to do robust sub pixel estimation. A new method based...

  10. Vision Screening

    Science.gov (United States)

    ... an efficient and cost-effective method to identify children with visual impairment or eye conditions that are likely to lead ... main goal of vision screening is to identify children who have or are at ... visual impairment unless treated in early childhood. Other problems that ...

  11. Healthy Vision Tips

    Science.gov (United States)

    ... for Kids >> Healthy Vision Tips Listen All About Vision About the Eye Ask a Scientist Video Series ... Links to More Information Optical Illusions Printables Healthy Vision Tips Healthy vision starts with you! Use these ...

  12. A vertebrate retina with segregated colour and polarization sensitivity.

    Science.gov (United States)

    Novales Flamarique, Iñigo

    2017-09-13

    Besides colour and intensity, some invertebrates are able to independently detect the polarization of light. Among vertebrates, such separation of visual modalities has only been hypothesized for some species of anchovies whose cone photoreceptors have unusual ultrastructure that varies with retinal location. Here, I tested this hypothesis by performing physiological experiments of colour and polarization discrimination using the northern anchovy, Engraulis mordax Optic nerve recordings showed that the ventro-temporal (VT), but not the ventro-nasal (VN), retina was polarization sensitive, and this coincided with the exclusive presence of polarization-sensitive photoreceptors in the VT retina. Spectral (colour) sensitivity recordings from the VN retina indicated the contribution of two spectral cone mechanisms to the optic nerve response, whereas only one contributed to the VT retina. This was supported by the presence of only one visual pigment in the VT retina and two in the VN retina, suggesting that only the VN retina was associated with colour sensitivity. Behavioural tests further demonstrated that anchovies could discriminate colour and the polarization of light using the ventral retina. Thus, in analogy with the visual system of some invertebrates, the northern anchovy has a retina with segregated retinal pathways for colour and polarization vision. © 2017 The Author(s).

  13. Lambda Vision

    Science.gov (United States)

    Czajkowski, Michael

    2014-06-01

    There is an explosion in the quantity and quality of IMINT data being captured in Intelligence Surveillance and Reconnaissance (ISR) today. While automated exploitation techniques involving computer vision are arriving, only a few architectures can manage both the storage and bandwidth of large volumes of IMINT data and also present results to analysts quickly. Lockheed Martin Advanced Technology Laboratories (ATL) has been actively researching in the area of applying Big Data cloud computing techniques to computer vision applications. This paper presents the results of this work in adopting a Lambda Architecture to process and disseminate IMINT data using computer vision algorithms. The approach embodies an end-to-end solution by processing IMINT data from sensors to serving information products quickly to analysts, independent of the size of the data. The solution lies in dividing up the architecture into a speed layer for low-latent processing and a batch layer for higher quality answers at the expense of time, but in a robust and fault-tolerant way. This approach was evaluated using a large corpus of IMINT data collected by a C-130 Shadow Harvest sensor over Afghanistan from 2010 through 2012. The evaluation data corpus included full motion video from both narrow and wide area field-of-views. The evaluation was done on a scaled-out cloud infrastructure that is similar in composition to those found in the Intelligence Community. The paper shows experimental results to prove the scalability of the architecture and precision of its results using a computer vision algorithm designed to identify man-made objects in sparse data terrain.

  14. Cartesian visions.

    Science.gov (United States)

    Fara, Patricia

    2008-12-01

    Few original portraits exist of René Descartes, yet his theories of vision were central to Enlightenment thought. French philosophers combined his emphasis on sight with the English approach of insisting that ideas are not innate, but must be built up from experience. In particular, Denis Diderot criticised Descartes's views by describing how Nicholas Saunderson--a blind physics professor at Cambridge--relied on touch. Diderot also made Saunderson the mouthpiece for some heretical arguments against the existence of God.

  15. Polarization Optics

    OpenAIRE

    Fressengeas, Nicolas

    2010-01-01

    The physics of polarization optics *Polarized light propagation *Partially polarized light; DEA; After a brief introduction to polarization optics, this lecture reviews the basic formalisms for dealing with it: Jones Calculus for totally polarized light and Stokes parameters associated to Mueller Calculus for partially polarized light.

  16. Exploring the entrance of proton pathways in cytochrome c oxidase from Paracoccus denitrificans: surface charge, buffer capacity and redox-dependent polarity changes at the internal surface.

    Science.gov (United States)

    Kirchberg, Kristina; Michel, Hartmut; Alexiev, Ulrike

    2013-03-01

    Cytochrome c oxidase (CcO), the terminal oxidase of cellular respiration, reduces molecular oxygen to water. The mechanism of proton pumping as well as the coupling of proton and electron transfer is still not understood in this redox-linked proton pump. Eleven residues at the aqueous-exposed surfaces of CcO from Paracoccus denitrificans have been exchanged to cysteines in a two-subunit base variant to yield single reactive cysteine variants. These variants are designed to provide unique labeling sites for probes to be used in spectroscopic experiments investigating the mechanism of proton pumping in CcO. To this end we have shown that all cysteine variants are enzymatically active. Cysteine positions at the negative (N-) side of the membrane are located close to the entrance of the D- and K-proton transfer pathways that connect the N-side with the catalytic oxygen reduction site. Labeling of the pH-indicator dye fluorescein to these sites allowed us to determine the surface potential at the cytoplasmic CcO surface, which corresponds to a surface charge density of -0.5 elementary charge/1000Å(2). In addition, acid-base titrations revealed values of CcO buffer capacity. Polarity measurements of the label environment at the N-side provided (i) site-specific values indicative of a hydrophilic and a more hydrophobic environment dependent on the label position, and (ii) information on a global change to a more apolar environment upon reduction of the enzyme. Thus, the redox state of the copper and heme centers inside the hydrophobic interior of CcO affect the properties at the cytoplasmic surface. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Embodied Visions

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    melodramas - from evolutionary and psychological perspectives, the author also reflects on social issues at the intersection of film theory and neuropsychology. These include moral problems in film viewing, ow we experience realism and character identification, and the value of the subjective forms......Embodied Visions presents a groundbreaking analysis of film through the lens of bioculturalism, revealing how human biology as well as human culture determine how films are made and experienced. Throughout the book the author uses the breakthroughs of modern brain science to explain general...

  18. Helminth-excreted/secreted products are recognized by multiple receptors on DCs to block the TLR response and bias Th2 polarization in a cRAF dependent pathway.

    Science.gov (United States)

    Terrazas, César A; Alcántara-Hernández, Marcela; Bonifaz, Laura; Terrazas, Luis I; Satoskar, Abhay R

    2013-11-01

    Dendritic cells (DCs) recognize pathogens and initiate the T-cell response. The DC-helminth interaction induces an immature phenotype in DCs; as a result, these DCs display impaired responses to TLR stimulation and prime Th2-type responses. However, the DC receptors and intracellular pathways targeted by helminth molecules and their importance in the initiation of the Th2 response are poorly understood. In this report, we found that products excreted/secreted by Taenia crassiceps (TcES) triggered cRAF phosphorylation through MGL, MR, and TLR2. TcES interfered with the LPS-induced NFκB p65 and p38 MAPK signaling pathways. In addition, TcES-induced cRAF signaling pathway was critical for down-regulation of the TLR-mediated DC maturation and secretion of IL-12 and TNF-α. Finally, we show for the first time that blocking cRAF in DCs abolishes their ability to induce Th2 polarization in vitro after TcES exposure. Our data demonstrate a new mechanism by which helminths target intracellular pathways to block DC maturation and efficiently program Th2 polarization.

  19. Pediatric Low Vision

    Science.gov (United States)

    ... Asked Questions Español Condiciones Chinese Conditions Pediatric Low Vision What is Low Vision? Partial vision loss that cannot be corrected causes ... and play. What are the signs of Low Vision? Some signs of low vision include difficulty recognizing ...

  20. Visions and visioning in foresight activities

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Grosu, Dan

    2007-01-01

    or not work. The theoretical part of the paper presents an actor-network theory approach to the analyses of visions and visioning processes, where the shaping of the visions and the visioning and what has made them work or not work is analysed. The empirical part is based on analyses of the roles of visions...... important aspect of visioning processes include the types of actors participating in the processes and the types of expertise included in the processes (scientific, lay, business etc.). The empirical part of the paper analyses eight national foresight activities from Denmark, Germany, Hungary, Malta...

  1. Robot vision

    International Nuclear Information System (INIS)

    Hall, E.L.

    1984-01-01

    Almost all industrial robots use internal sensors such as shaft encoders which measure rotary position, or tachometers which measure velocity, to control their motions. Most controllers also provide interface capabilities so that signals from conveyors, machine tools, and the robot itself may be used to accomplish a task. However, advanced external sensors, such as visual sensors, can provide a much greater degree of adaptability for robot control as well as add automatic inspection capabilities to the industrial robot. Visual and other sensors are now being used in fundamental operations such as material processing with immediate inspection, material handling with adaption, arc welding, and complex assembly tasks. A new industry of robot vision has emerged. The application of these systems is an area of great potential

  2. Vision Screening

    Science.gov (United States)

    1993-01-01

    The Visi Screen OSS-C, marketed by Vision Research Corporation, incorporates image processing technology originally developed by Marshall Space Flight Center. Its advantage in eye screening is speed. Because it requires no response from a subject, it can be used to detect eye problems in very young children. An electronic flash from a 35 millimeter camera sends light into a child's eyes, which is reflected back to the camera lens. The photorefractor then analyzes the retinal reflexes generated and produces an image of the child's eyes, which enables a trained observer to identify any defects. The device is used by pediatricians, day care centers and civic organizations that concentrate on children with special needs.

  3. Blindness and vision loss

    Science.gov (United States)

    ... life. Alternative Names Loss of vision; No light perception (NLP); Low vision; Vision loss and blindness Images ... ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow ...

  4. Impairments to Vision

    Science.gov (United States)

    ... an external Non-Government web site. Impairments to Vision Normal Vision Diabetic Retinopathy Age-related Macular Degeneration In this ... pictures, fixate on the nose to simulate the vision loss. In diabetic retinopathy, the blood vessels in ...

  5. All Vision Impairment

    Science.gov (United States)

    ... Prevalence Rates for Vision Impairment by Age and Race/Ethnicity Table for 2010 U.S. Age-Specific Prevalence ... Ethnicity 2010 Prevalence Rates of Vision Impairment by Race Table for 2010 Prevalence Rates of Vision Impairment ...

  6. Daily visual stimulation in the critical period enhances multiple aspects of vision through BDNF-mediated pathways in the mouse retina.

    Science.gov (United States)

    Mui, Amanda M; Yang, Victoria; Aung, Moe H; Fu, Jieming; Adekunle, Adewumi N; Prall, Brian C; Sidhu, Curran S; Park, Han Na; Boatright, Jeffrey H; Iuvone, P Michael; Pardue, Machelle T

    2018-01-01

    Visual experience during the critical period modulates visual development such that deprivation causes visual impairments while stimulation induces enhancements. This study aimed to determine whether visual stimulation in the form of daily optomotor response (OMR) testing during the mouse critical period (1) improves aspects of visual function, (2) involves retinal mechanisms and (3) is mediated by brain derived neurotrophic factor (BDNF) and dopamine (DA) signaling pathways. We tested spatial frequency thresholds in C57BL/6J mice daily from postnatal days 16 to 23 (P16 to P23) using OMR testing. Daily OMR-treated mice were compared to littermate controls that were placed in the OMR chamber without moving gratings. Contrast sensitivity thresholds, electroretinograms (ERGs), visual evoked potentials, and pattern ERGs were acquired at P21. To determine the role of BDNF signaling, a TrkB receptor antagonist (ANA-12) was systemically injected 2 hours prior to OMR testing in another cohort of mice. BDNF immunohistochemistry was performed on retina and brain sections. Retinal DA levels were measured using high-performance liquid chromatography. Daily OMR testing enhanced spatial frequency thresholds and contrast sensitivity compared to controls. OMR-treated mice also had improved rod-driven ERG oscillatory potential response times, greater BDNF immunoreactivity in the retinal ganglion cell layer, and increased retinal DA content compared to controls. VEPs and pattern ERGs were unchanged. Systemic delivery of ANA-12 attenuated OMR-induced visual enhancements. Daily OMR testing during the critical period leads to general visual function improvements accompanied by increased DA and BDNF in the retina, with this process being requisitely mediated by TrkB activation. These results suggest that novel combination therapies involving visual stimulation and using both behavioral and molecular approaches may benefit degenerative retinal diseases or amblyopia.

  7. TNF-α decreases VEGF secretion in highly polarized RPE cells but increases it in non-polarized RPE cells related to crosstalk between JNK and NF-κB pathways.

    Directory of Open Access Journals (Sweden)

    Hiroto Terasaki

    Full Text Available Asymmetrical secretion of vascular endothelial growth factor (VEGF by retinal pigment epithelial (RPE cells in situ is critical for maintaining the homeostasis of the retina and choroid. VEGF is also involved in the development and progression of age-related macular degeneration (AMD. We studied the effect of tumor necrosis factor-α (TNF-α on the secretion of VEGF in polarized and non-polarized RPE cells (P-RPE cells and N-RPE cells, respectively in culture and in situ in rats. A subretinal injection of TNF-α caused a decrease in VEGF expression and choroidal atrophy. Porcine RPE cells were seeded on Transwell™ filters, and their maturation and polarization were confirmed by the asymmetrical VEGF secretion and trans electrical resistance. Exposure to TNF-α decreased the VEGF secretion in P-RPE cells but increased it in N-RPE cells in culture. TNF-α inactivated JNK in P-RPE cells but activated it in N-RPE cells, and TNF-α activated NF-κB in P-RPE cells but not in N-RPE cells. Inhibition of NF-κB activated JNK in both types of RPE cells indicating crosstalk between JNK and NF-κB. TNF-α induced the inhibitory effects of NF-κB on JNK in P-RPE cells because NF-κB is continuously inactivated. In N-RPE cells, however, it was not evident because NF-κB was already activated. The basic activation pattern of JNK and NF-κB and their crosstalk led to opposing responses of RPE cells to TNF-α. These results suggest that VEGF secretion under inflammatory conditions depends on cellular polarization, and the TNF-α-induced VEGF down-regulation may result in choroidal atrophy in polarized physiological RPE cells. TNF-α-induced VEGF up-regulation may cause neovascularization by non-polarized or non-physiological RPE cells.

  8. Omega-3 polyunsaturated fatty acid attenuates the inflammatory response by modulating microglia polarization through SIRT1-mediated deacetylation of the HMGB1/NF-κB pathway following experimental traumatic brain injury.

    Science.gov (United States)

    Chen, Xiangrong; Chen, Chunnuan; Fan, Sining; Wu, Shukai; Yang, Fuxing; Fang, Zhongning; Fu, Huangde; Li, Yasong

    2018-04-20

    Microglial polarization and the subsequent neuroinflammatory response are contributing factors for traumatic brain injury (TBI)-induced secondary injury. High mobile group box 1 (HMGB1) mediates the activation of the NF-κB pathway, and it is considered to be pivotal in the late neuroinflammatory response. Activation of the HMGB1/NF-κB pathway is closely related to HMGB1 acetylation, which is regulated by the sirtuin (SIRT) family of proteins. Omega-3 polyunsaturated fatty acids (ω-3 PUFA) are known to have antioxidative and anti-inflammatory effects. We previously demonstrated that ω-3 PUFA inhibited TBI-induced microglial activation and the subsequent neuroinflammatory response by regulating the HMGB1/NF-κB signaling pathway. However, no studies have elucidated if ω-3 PUFA affects the HMGB1/NF-κB pathway in a HMGB1 deacetylation of dependent SIRT1 manner, thus regulating microglial polarization and the subsequent neuroinflammatory response. The Feeney DM TBI model was adopted to induce brain injury in rats. Modified neurological severity scores, rotarod test, brain water content, and Nissl staining were employed to determine the neuroprotective effects of ω-3 PUFA supplementation. Assessment of microglia polarization and pro-inflammatory markers, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and HMGB1, were used to evaluate the neuroinflammatory responses and the anti-inflammatory effects of ω-3 PUFA supplementation. Immunofluorescent staining and western blot analysis were used to detect HMGB1 nuclear translocation, secretion, and HMGB1/NF-κB signaling pathway activation to evaluate the effects of ω-3 PUFA supplementation. The impact of SIRT1 deacetylase activity on HMGB1 acetylation and the interaction between HMGB1 and SIRT1 were assessed to evaluate anti-inflammation effects of ω-3 PUFAs, and also, whether these effects were dependent on a SIRT1-HMGB1/NF-κB axis to gain further insight into the mechanisms underlying the

  9. Cataract Vision Simulator

    Science.gov (United States)

    ... and Videos: What Do Cataracts Look Like? Cataract Vision Simulator Leer en Español: Simulador: Catarata Jun. 11, 2014 How do cataracts affect your vision? A cataract is a clouding of the eye's ...

  10. Living with Low Vision

    Science.gov (United States)

    ... Life TIPS To Its Fullest LIVING WITH LOW VISION Savings Medical Bills A VARIETY OF EYE CONDITIONS, ... which occupational therapy practitioners help people with low vision to function at the highest possible level. • Prevent ...

  11. Vision - night blindness

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003039.htm Vision - night blindness To use the sharing features on ... page, please enable JavaScript. Night blindness is poor vision at night or in dim light. Considerations Night ...

  12. Chemicals Industry Vision

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1996-12-01

    Chemical industry leaders articulated a long-term vision for the industry, its markets, and its technology in the groundbreaking 1996 document Technology Vision 2020 - The U.S. Chemical Industry. (PDF 310 KB).

  13. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    Energy Technology Data Exchange (ETDEWEB)

    Adeyemi, Adeleke H. [Hampton Univ., Hampton, VA (United States); et al.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e⁻/e⁺ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high-Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high-energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  14. Robot Vision Library

    Science.gov (United States)

    Howard, Andrew B.; Ansar, Adnan I.; Litwin, Todd E.; Goldberg, Steven B.

    2009-01-01

    The JPL Robot Vision Library (JPLV) provides real-time robot vision algorithms for developers who are not vision specialists. The package includes algorithms for stereo ranging, visual odometry and unsurveyed camera calibration, and has unique support for very wideangle lenses

  15. Comparing Active Vision Models

    NARCIS (Netherlands)

    Croon, G.C.H.E. de; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.

    2009-01-01

    Active vision models can simplify visual tasks, provided that they can select sensible actions given incoming sensory inputs. Many active vision models have been proposed, but a comparative evaluation of these models is lacking. We present a comparison of active vision models from two different

  16. Comparing active vision models

    NARCIS (Netherlands)

    Croon, G.C.H.E. de; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.

    2009-01-01

    Active vision models can simplify visual tasks, provided that they can select sensible actions given incoming sensory inputs. Many active vision models have been proposed, but a comparative evaluation of these models is lacking. We present a comparison of active vision models from two different

  17. Computational approaches to vision

    Science.gov (United States)

    Barrow, H. G.; Tenenbaum, J. M.

    1986-01-01

    Vision is examined in terms of a computational process, and the competence, structure, and control of computer vision systems are analyzed. Theoretical and experimental data on the formation of a computer vision system are discussed. Consideration is given to early vision, the recovery of intrinsic surface characteristics, higher levels of interpretation, and system integration and control. A computational visual processing model is proposed and its architecture and operation are described. Examples of state-of-the-art vision systems, which include some of the levels of representation and processing mechanisms, are presented.

  18. A child's vision.

    Science.gov (United States)

    Nye, Christina

    2014-06-01

    Implementing standard vision screening techniques in the primary care practice is the most effective means to detect children with potential vision problems at an age when the vision loss may be treatable. A critical period of vision development occurs in the first few weeks of life; thus, it is imperative that serious problems are detected at this time. Although it is not possible to quantitate an infant's vision, evaluating ocular health appropriately can mean the difference between sight and blindness and, in the case of retinoblastoma, life or death. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Vision and vision-related outcome measures in multiple sclerosis

    DEFF Research Database (Denmark)

    Balcer, Laura J; Miller, David H; Reingold, Stephen C

    2015-01-01

    to the afferent visual pathway. Abnormal eye movements also are common in multiple sclerosis, but quantitative assessment methods that can be applied in practice and clinical trials are not readily available. We summarize here a comprehensive literature search and the discussion at a recent international meeting...... of investigators involved in the development and study of visual outcomes in multiple sclerosis, which had, as its overriding goals, to review the state of the field and identify areas for future research. We review data and principles to help us understand the importance of vision as a model for outcomes...

  20. Polarization developments

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist

  1. Colour vision deficiency.

    Science.gov (United States)

    Simunovic, M P

    2010-05-01

    Colour vision deficiency is one of the commonest disorders of vision and can be divided into congenital and acquired forms. Congenital colour vision deficiency affects as many as 8% of males and 0.5% of females--the difference in prevalence reflects the fact that the commonest forms of congenital colour vision deficiency are inherited in an X-linked recessive manner. Until relatively recently, our understanding of the pathophysiological basis of colour vision deficiency largely rested on behavioural data; however, modern molecular genetic techniques have helped to elucidate its mechanisms. The current management of congenital colour vision deficiency lies chiefly in appropriate counselling (including career counselling). Although visual aids may be of benefit to those with colour vision deficiency when performing certain tasks, the evidence suggests that they do not enable wearers to obtain normal colour discrimination. In the future, gene therapy remains a possibility, with animal models demonstrating amelioration following treatment.

  2. Polarization, political

    NARCIS (Netherlands)

    Wojcieszak, M.; Mazzoleni, G.; Barnhurst, K.G.; Ikeda, K.; Maia, R.C.M.; Wessler, H.

    2015-01-01

    Polarization has been studied in three different forms: on a social, group, and individual level. This entry first focuses on the undisputed phenomenon of elite polarization (i.e., increasing adherence of policy positions among the elites) and also outlines different approaches to assessing mass

  3. Polarization holography

    DEFF Research Database (Denmark)

    Nikolova, L.; Ramanujam, P.S.

    Current research into holography is concerned with applications in optically storing, retrieving, and processing information. Polarization holography has many unique properties compared to conventional holography. It gives results in high efficiency, achromaticity, and special polarization...... properties. This books reviews the research carried out in this field over the last 15 years. The authors provide basic concepts in polarization and the propagation of light through anisotropic materials, before presenting a sound theoretical basis for polarization holography. The fabrication...... and characterization of azobenzene based materials, which remain the most efficient for the purpose, is described in detail. This is followed by a description of other materials that are used in polarization holography. An in-depth description of various applications, including display holography and optical storage...

  4. A novel pathway for the synthesis of inositol phospholipids uses cytidine diphosphate (CDP)-inositol as donor of the polar head group.

    Science.gov (United States)

    Jorge, Carla D; Borges, Nuno; Santos, Helena

    2015-07-01

    We describe a novel biosynthetic pathway for glycerophosphoinositides in Rhodothermus marinus in which inositol is activated by cytidine triphosphate (CTP); this is unlike all known pathways that involve activation of the lipid group instead. This work was motivated by the detection in the R. marinus genome of a gene with high similarity to CTP:L-myo-inositol-1-phosphate cytidylyltransferase, the enzyme that synthesizes cytidine diphosphate (CDP)-inositol, a metabolite only known in the synthesis of di-myo-inositol phosphate. However, this solute is absent in R. marinus. The fate of radiolabelled CDP-inositol was investigated in cell extracts to reveal that radioactive inositol was incorporated into the chloroform-soluble fraction. Mass spectrometry showed that the major lipid product has a molecular mass of 810 Da and contains inositol phosphate and alkyl chains attached to glycerol by ether bonds. The occurrence of ether-linked lipids is rare in bacteria and has not been described previously in R. marinus. The relevant synthase was identified by functional expression of the candidate gene in Escherichia coli. The enzyme catalyses the transfer of L-myo-inositol-1-phosphate from CDP-inositol to dialkylether glycerol yielding dialkylether glycerophosphoinositol. Database searching showed homologous proteins in two bacterial classes, Sphingobacteria and Alphaproteobacteria. This is the first report of the involvement of CDP-inositol in phospholipid synthesis. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  5. Polar Bears

    Science.gov (United States)

    Amstrup, Steven C.; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    Polar bears (Ursus maritimus) are hunted throughout most of their range. In addition to hunting polar bears of the Beaufort Sea region are exposed to mineral and petroleum extraction and related human activities such as shipping road-building, and seismic testing (Stirling 1990).Little was known at the start of this project about how polar bears move about in their environment, and although it was understood that many bears travel across political borders, the boundaries of populations had not been delineated (Amstrup 1986, Amstrup et al. 1986, Amstrup and DeMaster 1988, Garner et al. 1994, Amstrup 1995, Amstrup et al. 1995, Amstrup 2000).As human populations increase and demands for polar bears and other arctic resources escalate, managers must know the sizes and distributions of the polar bear populations. Resource managers also need reliable estimates of breeding rates, reproductive intervals, litter sizes, and survival of young and adults.Our objectives for this research were 1) to determine the seasonal and annual movements of polar bears in the Beaufort Sea, 2) to define the boundaries of the population(s) using this region, 3) to determine the size and status of the Beaufort Sea polar bear population, and 4) to establish reproduction and survival rates (Amstrup 2000).

  6. FPGA Vision Data Architecture

    Science.gov (United States)

    Morfopoulos, Arin C.; Pham, Thang D.

    2013-01-01

    JPL has produced a series of FPGA (field programmable gate array) vision algorithms that were written with custom interfaces to get data in and out of each vision module. Each module has unique requirements on the data interface, and further vision modules are continually being developed, each with their own custom interfaces. Each memory module had also been designed for direct access to memory or to another memory module.

  7. Vision, reanimated and reimagined.

    Science.gov (United States)

    Edelman, Shimon

    2012-01-01

    The publication in 1982 of David Marr's Vision has delivered a singular boost and a course correction to the science of vision. Thirty years later, cognitive science is being transformed by the new ways of thinking about what it is that the brain computes, how it does that, and, most importantly, why cognition requires these computations and not others. This ongoing process still owes much of its impetus and direction to the sound methodology, engaging style, and unique voice of Marr's Vision.

  8. Vision and sketching.

    Science.gov (United States)

    Forbus, Kenneth D

    2012-01-01

    This essay reflects on the revolution David Marr brought about in vision research, and in cognitive science more broadly. I start with an insider's view, then examine the methodological impact of his framework in cognitive science in general. My group's work on sketch understanding descends from Marr's approach to vision, a connection which I make to provide a concrete illustration. I close with a few thoughts about how research in vision and other areas of cognitive science might come together in the future.

  9. Arctigenin ameliorates inflammation in vitro and in vivo by inhibiting the PI3K/AKT pathway and polarizing M1 macrophages to M2-like macrophages.

    Science.gov (United States)

    Hyam, Supriya R; Lee, In-Ah; Gu, Wan; Kim, Kyung-Ah; Jeong, Jin-Ju; Jang, Se-Eun; Han, Myung Joo; Kim, Dong-Hyun

    2013-05-15

    Seeds of Arctium lappa, containing arctigenin and its glycoside arctiin as main constituents, have been used as a diuretic, anti-inflammatory and detoxifying agent in Chinese traditional medicine. In our preliminary study, arctigenin inhibited IKKβ and NF-κB activation in peptidoglycan (PGN)- or lipopolysaccharide (LPS)-induced peritoneal macrophages. To understand the anti-inflammatory effect of arctigenin, we investigated its anti-inflammatory effect in LPS-stimulated peritoneal macrophages and on LPS-induced systemic inflammation as well as 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Arctigenin inhibited LPS-increased IL-1β, IL-6 and TNF-α expression in LPS-stimulated peritoneal macrophages, but increased LPS-reduced IL-10 and CD204 expression. Arctigenin inhibited LPS-induced PI3K, AKT and IKKβ phosphorylation, but did not suppress LPS-induced IRAK-1 phosphorylation. However, arctigenin did not inhibit NF-κB activation in LPS-stimulated PI3K siRNA-treated peritoneal macrophages. Arctigenin suppressed the binding of p-PI3K antibody and the nucleus translocation of NF-κB p65 in LPS-stimulated peritoneal macrophages. Arctigenin suppressed blood IL-1β and TNF-α level in mice systemically inflamed by intraperitoneal injection of LPS. Arctigenin also inhibited colon shortening, macroscopic scores and myeloperoxidase activity in TNBS-induced colitic mice. Arctigenin inhibited TNBS-induced IL-1β, TNF-α and IL-6 expression, as well as PI3K, AKT and IKKβ phosphorylation and NF-κB activation in mice, but increased IL-10 and CD204 expression. However, it did not affect IRAK-1 phosphorylation. Based on these findings, arctigenin may ameliorate inflammatory diseases, such as colitis, by inhibiting PI3K and polarizing M1 macrophages to M2-like macrophages. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Vision-based interaction

    CERN Document Server

    Turk, Matthew

    2013-01-01

    In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such

  11. Biomimetic machine vision system.

    Science.gov (United States)

    Harman, William M; Barrett, Steven F; Wright, Cameron H G; Wilcox, Michael

    2005-01-01

    Real-time application of digital imaging for use in machine vision systems has proven to be prohibitive when used within control systems that employ low-power single processors without compromising the scope of vision or resolution of captured images. Development of a real-time machine analog vision system is the focus of research taking place at the University of Wyoming. This new vision system is based upon the biological vision system of the common house fly. Development of a single sensor is accomplished, representing a single facet of the fly's eye. This new sensor is then incorporated into an array of sensors capable of detecting objects and tracking motion in 2-D space. This system "preprocesses" incoming image data resulting in minimal data processing to determine the location of a target object. Due to the nature of the sensors in the array, hyperacuity is achieved thereby eliminating resolutions issues found in digital vision systems. In this paper, we will discuss the biological traits of the fly eye and the specific traits that led to the development of this machine vision system. We will also discuss the process of developing an analog based sensor that mimics the characteristics of interest in the biological vision system. This paper will conclude with a discussion of how an array of these sensors can be applied toward solving real-world machine vision issues.

  12. Jane Addams’ Social Vision

    DEFF Research Database (Denmark)

    Villadsen, Kaspar

    2018-01-01

    resonated with key tenets of social gospel theology, which imbued her texts with an overarching vision of humanity’s progressive history. It is suggested that Addams’ vision of a major transition in industrial society, one involving a BChristian renaissance^ and individuals’ transformation into Bsocialized...

  13. Copenhagen Energy Vision

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Rasmus Søgaard; Connolly, David

    The short-term goal for The City of Copenhagen is a CO2 neutral energy supply by the year 2025, and the long-term vision for Denmark is a 100% renewable energy (RE) supply by the year 2050. In this project, it is concluded that Copenhagen plays a key role in this transition. The long-term vision...

  14. Machine Vision Handbook

    CERN Document Server

    2012-01-01

    The automation of visual inspection is becoming more and more important in modern industry as a consistent, reliable means of judging the quality of raw materials and manufactured goods . The Machine Vision Handbook  equips the reader with the practical details required to engineer integrated mechanical-optical-electronic-software systems. Machine vision is first set in the context of basic information on light, natural vision, colour sensing and optics. The physical apparatus required for mechanized image capture – lenses, cameras, scanners and light sources – are discussed followed by detailed treatment of various image-processing methods including an introduction to the QT image processing system. QT is unique to this book, and provides an example of a practical machine vision system along with extensive libraries of useful commands, functions and images which can be implemented by the reader. The main text of the book is completed by studies of a wide variety of applications of machine vision in insp...

  15. Light Vision Color

    Science.gov (United States)

    Valberg, Arne

    2005-04-01

    Light Vision Color takes a well-balanced, interdisciplinary approach to our most important sensory system. The book successfully combines basics in vision sciences with recent developments from different areas such as neuroscience, biophysics, sensory psychology and philosophy. Originally published in 1998 this edition has been extensively revised and updated to include new chapters on clinical problems and eye diseases, low vision rehabilitation and the basic molecular biology and genetics of colour vision. Takes a broad interdisciplinary approach combining basics in vision sciences with the most recent developments in the area Includes an extensive list of technical terms and explanations to encourage student understanding Successfully brings together the most important areas of the subject in to one volume

  16. Visions of the City

    DEFF Research Database (Denmark)

    Pinder, David

    Visions of the City is a dramatic account of utopian urbanism in the twentieth century. It explores radical demands for new spaces and ways of living, and considers their effects on planning, architecture and struggles to shape urban landscapes. Such visions, it shows, have played a crucial role...... to transform urban space and everyday life. He addresses in particular Constant's vision of New Babylon, finding within his proposals for future spaces produced through nomadic life, creativity and play a still powerful challenge to imagine cities otherwise. The book not only recovers vital moments from past...

  17. Anchoring visions in organizations

    DEFF Research Database (Denmark)

    Simonsen, Jesper

    1999-01-01

    This paper introduces the term 'anchoring' within systems development: Visions, developed through early systems design within an organization, need to be deeply rooted in the organization. A vision's rationale needs to be understood by those who decide if the vision should be implemented as well...... as by those involved in the actual implementation. A model depicting a recent trend within systems development is presented: Organizations rely on purchasing generic software products and/or software development outsourced to external contractors. A contemporary method for participatory design, where...

  18. Vision and vision-related outcome measures in multiple sclerosis

    Science.gov (United States)

    Balcer, Laura J.; Miller, David H.; Reingold, Stephen C.

    2015-01-01

    Visual impairment is a key manifestation of multiple sclerosis. Acute optic neuritis is a common, often presenting manifestation, but visual deficits and structural loss of retinal axonal and neuronal integrity can occur even without a history of optic neuritis. Interest in vision in multiple sclerosis is growing, partially in response to the development of sensitive visual function tests, structural markers such as optical coherence tomography and magnetic resonance imaging, and quality of life measures that give clinical meaning to the structure-function correlations that are unique to the afferent visual pathway. Abnormal eye movements also are common in multiple sclerosis, but quantitative assessment methods that can be applied in practice and clinical trials are not readily available. We summarize here a comprehensive literature search and the discussion at a recent international meeting of investigators involved in the development and study of visual outcomes in multiple sclerosis, which had, as its overriding goals, to review the state of the field and identify areas for future research. We review data and principles to help us understand the importance of vision as a model for outcomes assessment in clinical practice and therapeutic trials in multiple sclerosis. PMID:25433914

  19. Political polarization

    OpenAIRE

    Dixit, Avinash K.; Weibull, Jörgen W.

    2007-01-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  20. Political polarization.

    Science.gov (United States)

    Dixit, Avinash K; Weibull, Jörgen W

    2007-05-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  1. Eyeglasses for Vision Correction

    Science.gov (United States)

    ... light. Another option for vision correction with UV protection is prescription sunglasses . Also, for people who prefer one set of eyeglasses for both inside and outdoors, photochromatic lenses are ...

  2. Your Child's Vision

    Science.gov (United States)

    ... rubbing extreme light sensitivity poor focusing poor visual tracking (following an object) abnormal alignment or movement of ... MD Date reviewed: June 2014 More on this topic for: Parents Kids Teens Amblyopia Can Vision Problems ...

  3. Promoting Diversity Through Polar Interdisciplinary Coordinated Education (Polar ICE)

    Science.gov (United States)

    McDonnell, J. D.; Hotaling, L. A.; Garza, C.; Van Dyk, P. B.; Hunter-thomson, K. I.; Middendorf, J.; Daniel, A.; Matsumoto, G. I.; Schofield, O.

    2017-12-01

    Polar Interdisciplinary Coordinated Education (ICE) is an education and outreach program designed to provide public access to the Antarctic and Arctic regions through polar data and interactions with the scientists. The program provides multi-faceted science communication training for early career scientists that consist of a face-to face workshop and opportunities to apply these skills. The key components of the scientist training workshop include cultural competency training, deconstructing/decoding science for non-expert audiences, the art of telling science stories, and networking with members of the education and outreach community and reflecting on communication skills. Scientists partner with educators to provide professional development for K-12 educators and support for student research symposia. Polar ICE has initiated a Polar Literacy initiative that provides both a grounding in big ideas in polar science and science communication training designed to underscore the importance of the Polar Regions to the public while promoting interdisciplinary collaborations between scientists and educators. Our ultimate objective is to promote STEM identity through professional development of scientists and educators while developing career awareness of STEM pathways in Polar science.

  4. Mining Industry of the Future Vision: The Future Begins with Mining

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1998-09-01

    The Mining Industry of the Future was started in June 1998 when the Chairman of the National Mining Association and the Secretary of Energy entered into a Compact to pursue a collaborative technology research partnership. After the Compact signing, the mining industry developed its vision document, The Future Begins with Mining, A Vision of the Mining Industry of the Future, in September 1998. This vision document lists long-term goals for the mining industry. Stemming from this vision document, targeted technology roadmaps were developed that describe pathways of research to achieve the vision goals.

  5. IDA's Energy Vision 2050

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik; Hansen, Kenneth

    IDA’s Energy Vision 2050 provides a Smart Energy System strategy for a 100% renewable Denmark in 2050. The vision presented should not be regarded as the only option in 2050 but as one scenario out of several possibilities. With this vision the Danish Society of Engineers, IDA, presents its third...... contribution for an energy strategy for Denmark. The IDA’s Energy Plan 2030 was prepared in 2006 and IDA’s Climate Plan was prepared in 2009. IDA’s Energy Vision 2050 is developed for IDA by representatives from The Society of Engineers and by a group of researchers at Aalborg University. It is based on state......-of-the-art knowledge about how low cost energy systems can be designed while also focusing on long-term resource efficiency. The Energy Vision 2050 has the ambition to focus on all parts of the energy system rather than single technologies, but to have an approach in which all sectors are integrated. While Denmark...

  6. [Quality system Vision 2000].

    Science.gov (United States)

    Pasini, Evasio; Pitocchi, Oreste; de Luca, Italo; Ferrari, Roberto

    2002-12-01

    A recent document of the Italian Ministry of Health points out that all structures which provide services to the National Health System should implement a Quality System according to the ISO 9000 standards. Vision 2000 is the new version of the ISO standard. Vision 2000 is less bureaucratic than the old version. The specific requests of the Vision 2000 are: a) to identify, to monitor and to analyze the processes of the structure, b) to measure the results of the processes so as to ensure that they are effective, d) to implement actions necessary to achieve the planned results and the continual improvement of these processes, e) to identify customer requests and to measure customer satisfaction. Specific attention should be also dedicated to the competence and training of the personnel involved in the processes. The principles of the Vision 2000 agree with the principles of total quality management. The present article illustrates the Vision 2000 standard and provides practical examples of the implementation of this standard in cardiological departments.

  7. Colour, vision and ergonomics.

    Science.gov (United States)

    Pinheiro, Cristina; da Silva, Fernando Moreira

    2012-01-01

    This paper is based on a research project - Visual Communication and Inclusive Design-Colour, Legibility and Aged Vision, developed at the Faculty of Architecture of Lisbon. The research has the aim of determining specific design principles to be applied to visual communication design (printed) objects, in order to be easily read and perceived by all. This study target group was composed by a selection of socially active individuals, between 55 and 80 years, and we used cultural events posters as objects of study and observation. The main objective is to overlap the study of areas such as colour, vision, older people's colour vision, ergonomics, chromatic contrasts, typography and legibility. In the end we will produce a manual with guidelines and information to apply scientific knowledge into the communication design projectual practice. Within the normal aging process, visual functions gradually decline; the quality of vision worsens, colour vision and contrast sensitivity are also affected. As people's needs change along with age, design should help people and communities, and improve life quality in the present. Applying principles of visually accessible design and ergonomics, the printed design objects, (or interior spaces, urban environments, products, signage and all kinds of visually information) will be effective, easier on everyone's eyes not only for visually impaired people but also for all of us as we age.

  8. Overview of sports vision

    Science.gov (United States)

    Moore, Linda A.; Ferreira, Jannie T.

    2003-03-01

    Sports vision encompasses the visual assessment and provision of sports-specific visual performance enhancement and ocular protection for athletes of all ages, genders and levels of participation. In recent years, sports vision has been identified as one of the key performance indicators in sport. It is built on four main cornerstones: corrective eyewear, protective eyewear, visual skills enhancement and performance enhancement. Although clinically well established in the US, it is still a relatively new area of optometric specialisation elsewhere in the world and is gaining increasing popularity with eyecare practitioners and researchers. This research is often multi-disciplinary and involves input from a variety of subject disciplines, mainly those of optometry, medicine, physiology, psychology, physics, chemistry, computer science and engineering. Collaborative research projects are currently underway between staff of the Schools of Physics and Computing (DIT) and the Academy of Sports Vision (RAU).

  9. Interoperability Strategic Vision

    Energy Technology Data Exchange (ETDEWEB)

    Widergren, Steven E.; Knight, Mark R.; Melton, Ronald B.; Narang, David; Martin, Maurice; Nordman, Bruce; Khandekar, Aditya; Hardy, Keith S.

    2018-02-28

    The Interoperability Strategic Vision whitepaper aims to promote a common understanding of the meaning and characteristics of interoperability and to provide a strategy to advance the state of interoperability as applied to integration challenges facing grid modernization. This includes addressing the quality of integrating devices and systems and the discipline to improve the process of successfully integrating these components as business models and information technology improve over time. The strategic vision for interoperability described in this document applies throughout the electric energy generation, delivery, and end-use supply chain. Its scope includes interactive technologies and business processes from bulk energy levels to lower voltage level equipment and the millions of appliances that are becoming equipped with processing power and communication interfaces. A transformational aspect of a vision for interoperability in the future electric system is the coordinated operation of intelligent devices and systems at the edges of grid infrastructure. This challenge offers an example for addressing interoperability concerns throughout the electric system.

  10. Bio-inspired vision

    International Nuclear Information System (INIS)

    Posch, C

    2012-01-01

    Nature still outperforms the most powerful computers in routine functions involving perception, sensing and actuation like vision, audition, and motion control, and is, most strikingly, orders of magnitude more energy-efficient than its artificial competitors. The reasons for the superior performance of biological systems are subject to diverse investigations, but it is clear that the form of hardware and the style of computation in nervous systems are fundamentally different from what is used in artificial synchronous information processing systems. Very generally speaking, biological neural systems rely on a large number of relatively simple, slow and unreliable processing elements and obtain performance and robustness from a massively parallel principle of operation and a high level of redundancy where the failure of single elements usually does not induce any observable system performance degradation. In the late 1980's, Carver Mead demonstrated that silicon VLSI technology can be employed in implementing ''neuromorphic'' circuits that mimic neural functions and fabricating building blocks that work like their biological role models. Neuromorphic systems, as the biological systems they model, are adaptive, fault-tolerant and scalable, and process information using energy-efficient, asynchronous, event-driven methods. In this paper, some basics of neuromorphic electronic engineering and its impact on recent developments in optical sensing and artificial vision are presented. It is demonstrated that bio-inspired vision systems have the potential to outperform conventional, frame-based vision acquisition and processing systems in many application fields and to establish new benchmarks in terms of redundancy suppression/data compression, dynamic range, temporal resolution and power efficiency to realize advanced functionality like 3D vision, object tracking, motor control, visual feedback loops, etc. in real-time. It is argued that future artificial vision systems

  11. Representing vision and blindness.

    Science.gov (United States)

    Ray, Patrick L; Cox, Alexander P; Jensen, Mark; Allen, Travis; Duncan, William; Diehl, Alexander D

    2016-01-01

    There have been relatively few attempts to represent vision or blindness ontologically. This is unsurprising as the related phenomena of sight and blindness are difficult to represent ontologically for a variety of reasons. Blindness has escaped ontological capture at least in part because: blindness or the employment of the term 'blindness' seems to vary from context to context, blindness can present in a myriad of types and degrees, and there is no precedent for representing complex phenomena such as blindness. We explore current attempts to represent vision or blindness, and show how these attempts fail at representing subtypes of blindness (viz., color blindness, flash blindness, and inattentional blindness). We examine the results found through a review of current attempts and identify where they have failed. By analyzing our test cases of different types of blindness along with the strengths and weaknesses of previous attempts, we have identified the general features of blindness and vision. We propose an ontological solution to represent vision and blindness, which capitalizes on resources afforded to one who utilizes the Basic Formal Ontology as an upper-level ontology. The solution we propose here involves specifying the trigger conditions of a disposition as well as the processes that realize that disposition. Once these are specified we can characterize vision as a function that is realized by certain (in this case) biological processes under a range of triggering conditions. When the range of conditions under which the processes can be realized are reduced beyond a certain threshold, we are able to say that blindness is present. We characterize vision as a function that is realized as a seeing process and blindness as a reduction in the conditions under which the sight function is realized. This solution is desirable because it leverages current features of a major upper-level ontology, accurately captures the phenomenon of blindness, and can be

  12. En vision for CBS?

    DEFF Research Database (Denmark)

    Thyssen, Ole

    2015-01-01

    Kommentar. CBS’ ry for at være et moderne Business University med forskere fra hele verden og forskningsmæssig dynamik faldt på gulvet. Udfordringen er nu at få samlet CBS forskere om en fælles vision.......Kommentar. CBS’ ry for at være et moderne Business University med forskere fra hele verden og forskningsmæssig dynamik faldt på gulvet. Udfordringen er nu at få samlet CBS forskere om en fælles vision....

  13. Strategic Polarization.

    Science.gov (United States)

    Kalai, Adam; Kalai, Ehud

    2001-08-01

    In joint decision making, similarly minded people may take opposite positions. Consider the example of a marriage in which one spouse gives generously to charity while the other donates nothing. Such "polarization" may misrepresent what is, in actuality, a small discrepancy in preferences. It may be that the donating spouse would like to see 10% of their combined income go to charity each year, while the apparently frugal spouse would like to see 8% donated. A simple game-theoretic analysis suggests that the spouses will end up donating 10% and 0%, respectively. By generalizing this argument to a larger class of games, we provide strategic justification for polarization in many situations such as debates, shared living accommodations, and disciplining children. In some of these examples, an arbitrarily small disagreement in preferences leads to an arbitrarily large loss in utility for all participants. Such small disagreements may also destabilize what, from game-theoretic point of view, is a very stable equilibrium. Copyright 2001 Academic Press.

  14. Videographic Education: Owning the Polar Crisis

    Science.gov (United States)

    Vachon, R. W.; Buhr, S. M.

    2007-12-01

    Television and internet-served video is an increasingly important media tool for reaching into society. This talk will present clips from a film designed to educate the public about warming in the polar regions, the socioeconomic and environmental implications of this warming; and the actions we can take to slow down human contributions to climate change. This talk will present a short film Owning the Polar Crisis, which is drawn from footage for Polar Visions, a four segment film available for educational audiences and the public.. The films are unique in that they draw from the perspectives of well-known climate scientists, citizens from all over the planet and natives of the Arctic. The compelling images were taken from numerous locations around the Arctic, including Alaska and Greenland. Owning the Polar Crisis was filmed, directed and produced by Dr. Ryan Vachon, a climate scientist and videographer with an intimate knowledge of the subject matter.

  15. Operational Based Vision Assessment Automated Vision Test Collection User Guide

    Science.gov (United States)

    2017-05-15

    14. ABSTRACT The U.S. Air Force School of Aerospace Medicine Operational Based Vision Assessment Laboratory has developed a set of computer - based...Air Force School of Aerospace Medicine Operational Based Vision Assessment (OBVA) Laboratory has developed a set of computer -based, automated vision ...username of your computer ]  “App Data”  “Roaming”  Automated Vision Test”  “Settings”  “Calibration.” Once inside the “Calibration” folder

  16. Effects of visual skills training, vision coaching and sports vision ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the effectiveness of three different approaches to improving sports performance through improvements in “sports vision:” (1) a visual skills training programme, (2) traditional vision coaching sessions, and (3) a multi-disciplinary approach identified as sports vision dynamics.

  17. Near vision spectacle coverage and barriers to near vision ...

    African Journals Online (AJOL)

    easily help to address this visual disability.7 An average cost of near vision spectacle in Ghana is approximately. $ 5.8 Near-vision spectacle could be dispensed as single vision, bifocal or progressive eye glasses to meet near vi- sion needs.2. Recent evidence suggests that the ageing population in. Ghana is increasing ...

  18. Grounding Our Vision: Brain Research and Strategic Vision

    Science.gov (United States)

    Walker, Mike

    2011-01-01

    While recognizing the value of "vision," it could be argued that vision alone--at least in schools--is not enough to rally the financial and emotional support required to translate an idea into reality. A compelling vision needs to reflect substantive, research-based knowledge if it is to spark the kind of strategic thinking and insight…

  19. KiWi Vision

    DEFF Research Database (Denmark)

    Schaffert, Sebastian; Bry, Francois; Dolog, Peter

    This deliverable describes the common vision of the KiWi project, ranging from motivation over use cases and usage scenarios to user interaction, system architecture and technologies, and the research that is performed as part of the project. The deliverable is intended for a wide audience to give...

  20. Vision eller verklighet?

    DEFF Research Database (Denmark)

    Andersson, Jonas E

    2012-01-01

    and drawing analysis. This study suggests that there is a gap between reality and visions. Despite research-based guidelines, the architecture of contemporary residential care homes relies on universal qualities that are associated with the home environment rather than with the particular conditions...

  1. Tectonic vision in architecture

    DEFF Research Database (Denmark)

    Beim, Anne

    1999-01-01

    By introducing the concept; Tectonic Visions, The Dissertation discusses the interrelationship between the basic idea, the form principles, the choice of building technology and constructive structures within a given building. Includes Mies van der Rohe, Le Corbusier, Eames, Jorn Utzon, Louis Kahn...

  2. Giving Machines the Vision

    Science.gov (United States)

    1999-01-01

    Amherst Systems manufactures foveal machine vision technology and systems commercially available to end-users and system integrators. This technology was initially developed under NASA contracts NAS9-19335 (Johnson Space Center) and NAS1-20841 (Langley Research Center). This technology is currently being delivered to university research facilities and military sites. More information may be found in www.amherst.com.

  3. Direct vision internal urethrotomy

    DEFF Research Database (Denmark)

    Jakobsen, H; Willumsen, H; Søndergaard Jensen, L

    1984-01-01

    During a five-year period, direct vision internal urethrotomy was used for the treatment of urethral strictures in 34 men. After the primary operation the patients were followed for an average period of 29 months (range 3-73 months). During this period 53% of the patients were found to have one...

  4. Vision: Essential Scaffolding

    Science.gov (United States)

    Murphy, Joseph; Torre, Daniela

    2015-01-01

    Few concepts are more noted in the leadership effects research than vision. It is a cardinal element in the school improvement equation as well. Yet, it remains one of the least well-specified components of that algorithm. Based on a comprehensive review of the research on effective leadership and school improvement from 1995 to 2012, we bring…

  5. Tectonic vision in architecture

    DEFF Research Database (Denmark)

    Beim, Anne

    1999-01-01

    By introducing the concept; Tectonic Visions, The Dissertation discusses the interrelationship between the basic idea, the form principles, the choice of building technology and constructive structures within a given building. Includes Mies van der Rohe, Le Corbusier, Eames, Jorn Utzon, Louis Kah...

  6. Home vision tests

    Science.gov (United States)

    ... missing areas. If any lines appear distorted or broken, note their location on the grid using a pen or pencil. DISTANCE VISION This is the standard eye chart doctors use, which has been adapted for home use. The chart is attached to a wall ...

  7. The Photodynamics of Vision

    Indian Academy of Sciences (India)

    rruion is one of our primary senses. It is the ability to identify, process and interpret what is seen by the eye. It is a powerful mechanism for parallel processing of information received at the speed of light from near and remote scenes. The volume of information received by vision is certainly more than that re- ceived by our ...

  8. MARR: active vision model

    Science.gov (United States)

    Podladchikova, Lubov N.; Gusakova, Valentina I.; Shaposhnikov, Dmitry G.; Faure, Alain; Golovan, Alexander V.; Shevtsova, Natalia A.

    1997-09-01

    Earlier, the biologically plausible active vision, model for multiresolutional attentional representation and recognition (MARR) has been developed. The model is based on the scanpath theory of Noton and Stark and provides invariant recognition of gray-level images. In the present paper, the algorithm of automatic image viewing trajectory formation in the MARR model, the results of psychophysical experiments, and possible applications of the model are considered. Algorithm of automatic image viewing trajectory formation is based on imitation of the scanpath formed by operator. Several propositions about possible mechanisms for a consecutive selection of fixation points in human visual perception inspired by computer simulation results and known psychophysical data have been tested and confirmed in our psychophysical experiments. In particular, we have found that gaze switch may be directed (1) to a peripheral part of the vision field which contains an edge oriented orthogonally to the edge in the point of fixation, and (2) to a peripheral part of the vision field containing crossing edges. Our experimental results have been used to optimize automatic algorithm of image viewing in the MARR model. The modified model demonstrates an ability to recognize complex real world images invariantly with respect to scale, shift, rotation, illumination conditions, and, in part, to point of view and can be used to solve some robot vision tasks.

  9. INL Vision and Strategy 2015

    International Nuclear Information System (INIS)

    Pillai, Rekha Sukamar

    2015-01-01

    This Laboratory vision and strategy presents INL's vision and strategy for the Laboratory and is our introduction to a special place dedicated to improving our nation's energy security future.

  10. What is vision Hampton Roads?

    Science.gov (United States)

    2010-01-01

    What is Vision Hampton Roads? : Vision Hampton Roads is... : A regionwide economic development strategy based on the collective strengths of all : localities of Hampton Roads, created with the input of business, academia, nonprofits, : government,...

  11. Vision in water.

    Science.gov (United States)

    Atchison, David A; Valentine, Emma L; Gibson, Georgina; Thomas, Hannah R; Oh, Sera; Pyo, Young Ah; Lacherez, Philippe; Mathur, Ankit

    2013-09-06

    The purpose of this study is to determine visual performance in water, including the influence of pupil size. The water environment was simulated by placing goggles filled with saline in front of the eyes with apertures placed at the front of the goggles. Correction factors were determined for the different magnification under this condition in order to estimate vision in water. Experiments were conducted on letter visual acuity (seven participants), grating resolution (eight participants), and grating contrast sensitivity (one participant). For letter acuity, mean loss of vision in water, compared to corrected vision in air, varied between 1.1 log min of arc resolution (logMAR) for a 1 mm aperture to 2.2 logMAR for a 7 mm aperture. The vision in min of arc was described well by a linear relationship with pupil size. For grating acuity, mean loss varied between 1.1 logMAR for a 2 mm aperture to 1.2 logMAR for a 6 mm aperture. Contrast sensitivity for a 2 mm aperture deteriorated as spatial frequency increased with a 2 log unit loss by 3 c/°. Superimposed on this deterioration were depressions (notches) in sensitivity with the first three notches occurring at 0.45, 0.8, and 1.3 c/° with estimates for water of 0.39, 0.70, and 1.13 c/°. In conclusion, vision in water is poor. It becomes worse as pupil size increases, but the effects are much more marked for letter targets than for grating targets.

  12. Vision based flight procedure stereo display system

    Science.gov (United States)

    Shen, Xiaoyun; Wan, Di; Ma, Lan; He, Yuncheng

    2008-03-01

    A virtual reality flight procedure vision system is introduced in this paper. The digital flight map database is established based on the Geographic Information System (GIS) and high definitions satellite remote sensing photos. The flight approaching area database is established through computer 3D modeling system and GIS. The area texture is generated from the remote sensing photos and aerial photographs in various level of detail. According to the flight approaching procedure, the flight navigation information is linked to the database. The flight approaching area vision can be dynamic displayed according to the designed flight procedure. The flight approaching area images are rendered in 2 channels, one for left eye images and the others for right eye images. Through the polarized stereoscopic projection system, the pilots and aircrew can get the vivid 3D vision of the flight destination approaching area. Take the use of this system in pilots preflight preparation procedure, the aircrew can get more vivid information along the flight destination approaching area. This system can improve the aviator's self-confidence before he carries out the flight mission, accordingly, the flight safety is improved. This system is also useful in validate the visual flight procedure design, and it helps to the flight procedure design.

  13. Precessing deuteron polarization

    International Nuclear Information System (INIS)

    Sitnik, I.M.; Volkov, V.I.; Kirillov, D.A.; Piskunov, N.M.; Plis, Yu.A.

    2002-01-01

    The feasibility of the acceleration in the Nuclotron of deuterons polarized in the horizontal plane is considered. This horizontal polarization is named precessing polarization. The effects of the main magnetic field and synchrotron oscillations are included. The precessing polarization is supposed to be used in studying the polarization parameters of the elastic dp back-scattering and other experiments

  14. Vision Care and the Nation's Children.

    Science.gov (United States)

    American Optometric Association, St. Louis, MO.

    Aspects of vision and vision care considered are the following: extent and types of vision defects of American children; importance of vision care in pre-school years, elementary, and secondary school and beyond; and manpower resources in vision care today, the extent of vision testing and care, special problem areas, and governmental support.…

  15. Realisering af Vision 2020

    DEFF Research Database (Denmark)

    Bertelsen, Niels Haldor; Hansen, Ernst Jan de Place

    Repræsentanter for byggesektoren har på 11 dialogmøder drøftet Erhvervs- og Byggestyrelsens "Vision 2020 - Byggeri med mening". Drøftelserne førte til formulering af en lang række initiativforslag til realisering af visionen. Den mest centrale udfordring bliver at reducere fejl og mangler i...... byggeriet. Branchen lægger også vægt på, at styringen af Vision 2020s reaisering sker i byggesektoren. Initiativforslagene er i rapporten samlet under 3 hovedområder. Det første hovedområde lægger vægt på bygningerne, brugerbehov og det globale samfund. Det andet omhandler processen og leverancesystemet...

  16. Robotic Vision for Welding

    Science.gov (United States)

    Richardson, R. W.

    1986-01-01

    Vision system for robotic welder looks at weld along axis of welding electrode. Gives robot view of most of weld area, including yet-unwelded joint, weld pool, and completed weld bead. Protected within welding-torch body, lens and fiber bundle give robot closeup view of weld in progress. Relayed to video camera on robot manipulator frame, weld image provides data for automatic control of robot motion and welding parameters.

  17. 2015 Enterprise Strategic Vision

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-08-01

    This document aligns with the Department of Energy Strategic Plan for 2014-2018 and provides a framework for integrating our missions and direction for pursuing DOE’s strategic goals. The vision is a guide to advancing world-class science and engineering, supporting our people, modernizing our infrastructure, and developing a management culture that operates a safe and secure enterprise in an efficient manner.

  18. Research for VISION 2020

    Directory of Open Access Journals (Sweden)

    Peter Ackland

    2010-12-01

    Full Text Available We need good quality information to be able to carry out our eye care programmes in support of VISION 2020, to measure (and improve our performance, and to advocate for the resources and support we need to succeed. Much of this information can be collected, analysed, and used as part of our daily work, as many of the articles in this issue show.

  19. Anterior communicating artery aneurysm presenting with vision loss

    Directory of Open Access Journals (Sweden)

    Dhaval P Shukla

    2013-01-01

    Full Text Available Anterior communicating artery aneurysm rarely presents with symptoms of compression of anterior visual pathways. We report a case of 65 years old man, who had complete loss of vision in right eye and temporal hemianopsia in left eye due to giant anterior communicating artery aneurysm.

  20. Anterior communicating artery aneurysm presenting with vision loss

    OpenAIRE

    Shukla, Dhaval P.; Bhat, Dhananjaya I.; Devi, Bhagavatula I.

    2013-01-01

    Anterior communicating artery aneurysm rarely presents with symptoms of compression of anterior visual pathways. We report a case of 65 years old man, who had complete loss of vision in right eye and temporal hemianopsia in left eye due to giant anterior communicating artery aneurysm.

  1. Anterior communicating artery aneurysm presenting with vision loss.

    Science.gov (United States)

    Shukla, Dhaval P; Bhat, Dhananjaya I; Devi, Bhagavatula I

    2013-07-01

    Anterior communicating artery aneurysm rarely presents with symptoms of compression of anterior visual pathways. We report a case of 65 years old man, who had complete loss of vision in right eye and temporal hemianopsia in left eye due to giant anterior communicating artery aneurysm.

  2. Polare maskuliniteter

    Directory of Open Access Journals (Sweden)

    Marit Anne Hauan

    2012-05-01

    Full Text Available In this paper my aim is to read and understand the journal of Gerrit de Veer from the last journey of William Barents to the Arctic Regions in 1596 and the journal of captain Junge on his hunting trip from Tromsø to Svalbard in 1834.It is nearly 240 years between this to voyages. The first journal is known as the earliest report from the arctic era. Gerrit de Veer adds instructive copper engravings to his text and give us insight in the crews meeting with this new land. Captain Junges journal is found together with his dead crew in a house in a fjord nearby Ny-Ålesund and has no drawings, but word. Both of these journals may be read as sources of the knowledge and understanding of the polar region. They might also unveil the ideas of how to deal with and survive under the challenges that is given. In addition one can ask if the sources can tell us more about how men describe their challenges. Can the way they expressed themselves in the journals give us an understanding of masculinity? And not least help us to create good questions of the change in the ideas of masculinities which is said to follow the change in understanding of the wilderness.

  3. Ecstasy and vision

    Directory of Open Access Journals (Sweden)

    Anders Hultgård

    1981-01-01

    Full Text Available In this paper we shall present some observations on the role played by ecstasy in the activity of the seer, as he emerges in ancient Jewish and Iranian texts. In the Jewish religious literature of the Hellenistic-Roman period, visions are described on almost every page, and visions were the most important means of divine revelation. Specific techniques for inducing the ecstatic state are not recorded in the Jewish sources. Some elements in the pattern leading up to the vision may be interpreted as parts of a method for inducing the final ecstasy; i.e. fasting and prayer. The Iranian material shows clearly the importance of ecstasy in the activity of the seer. The ecstatic seeing also means that the visionary shares with Ahura Mazda a divine quality, the "wisdom of omniscience". The granting of the "wisdom of omniscience" appears as a temporary and it conveys to the visionary a supernatural seeing. There is evidence to suggest that chanting was an important method of inducing ecstasy within the early Zoroastrian community. We do not find in the Jewish material a clear correspondence to the Iranian notion of "omniscient wisdom".

  4. Vision defects in albinism.

    Science.gov (United States)

    Pérez-Carpinell, J; Capilla, P; Illueca, C; Morales, J

    1992-08-01

    We have examined the possible presence of color vision anomalies in 9 individuals (17 eyes, 1 blind) with fundus findings suggesting ocular albinism using the Ishihara plates, the 28-hue Roth test, and the Davico anomaloscope. Results indicate that four of these individuals show no sign of the anomalies expected in an albino in either of the two eyes. Of the remaining cases, two are simple deuteranomals in both eyes, according to Pickford's classification criteria. The rest have protanomaly; however, in these the deviation toward red appears in both eyes in only one subject, whereas in the other two subjects it appears in only one eye, their binocular color vision being basically normal. Our study shows that a large proportion of these albinos have photophobia, pendular nystagmus, strabismus, noticeable refractive errors (astigmatism and high myopia), and poor visual acuity [usually less than 6/30 (20/100) with correction]. The measurement of contrast sensitivity function (CSF) indicates that the frequency of 12 cpd cannot be perceived, even in binocular vision.

  5. Vision under mesopic and scotopic illumination

    Directory of Open Access Journals (Sweden)

    Andrew J Zele

    2015-01-01

    Full Text Available Evidence has accumulated that rod activation under mesopic and scotopic light levels alters visual perception and performance. Here we review the most recent developments in the measurement of rod and cone contributions to mesopic color perception and temporal processing, with a focus on data measured using the four-primary photostimulator method that independently controls rod and cone excitations. We discuss the findings in the context of rod inputs to the three primary retinogeniculate pathways to understand rod contributions to mesopic vision. Additionally, we present evidence that hue perception is possible under scotopic, pure rod-mediated conditions that involves cortical mechanisms.

  6. Mercury biomagnification in polar bears ( Ursus maritimus)

    Science.gov (United States)

    Horton, T. W.; Blum, J. D.; Xie, Z.; Hren, M.; Chamberlain, C. P.

    2007-12-01

    Mercury biomagnification occurs in a variety of ecosystems resulting in greater potential for toxicological effects in higher-level trophic feeders. However, Hg transport pathways through different foodweb channels are not well known, particularly in high-latitude systems affected by atmospheric Hg deposition associated with snow and ice. Stable carbon and nitrogen isotope ratios and Hg concentrations determined for 26 late 19th and early 20th century polar bear hair specimens collected from cataloged museum collections elucidate relationships between high latitude marine foodweb structure and Hg transport pathways. Nitrogen and carbon isotopic compositions suggest that polar bears derive nutrition from both open water (pelagic) and ice associated (sympagic) foodweb channels. Correlation between Hg concentrations and nitrogen isotope compositions indicate mercury biomagnification occurred in most of the polar bears investigated. Interpretation of stable isotope based foodweb structure in concert with Hg concentrations further suggests that Hg biomagnification occurred to a greater degree in polar bears participating in pelagic foodweb channels.

  7. Optimization of Stereo Matching in 3D Reconstruction Based on Binocular Vision

    Science.gov (United States)

    Gai, Qiyang

    2018-01-01

    Stereo matching is one of the key steps of 3D reconstruction based on binocular vision. In order to improve the convergence speed and accuracy in 3D reconstruction based on binocular vision, this paper adopts the combination method of polar constraint and ant colony algorithm. By using the line constraint to reduce the search range, an ant colony algorithm is used to optimize the stereo matching feature search function in the proposed search range. Through the establishment of the stereo matching optimization process analysis model of ant colony algorithm, the global optimization solution of stereo matching in 3D reconstruction based on binocular vision system is realized. The simulation results show that by the combining the advantage of polar constraint and ant colony algorithm, the stereo matching range of 3D reconstruction based on binocular vision is simplified, and the convergence speed and accuracy of this stereo matching process are improved.

  8. Insect-vision inspired collision warning vision processor for automobiles

    OpenAIRE

    Liñán-Cembrano, G.; Carranza-González, L.; Rind, Claire; Zarandy, A.; Soininen, Martti; Rodríguez-Vázquez, Ángel

    2008-01-01

    Vision is expected to play important roles for car safety enhancement. Imaging systems can be used to enlarging the vision field of the driver. For instance capturing and displaying views of hidden areas around the car which the driver can analyze for safer decision-making. Vision systems go a step further. They can autonomously analyze the visual information, identify dangerous situations and prompt the delivery of warning signals. For instance in case of road lane departure, if an overtakin...

  9. Company Vision and Organizational Learning

    Directory of Open Access Journals (Sweden)

    Vojko Toman

    2015-11-01

    Full Text Available The effectiveness of a company is largely dependent on the company itself; it depends above all on its corporate governance, management, and implementation, as well as on decision-making processes and coordination. Many authors believe that organizational learning and knowledge are the most relevant aspects of company effectiveness. If a company wants to be effective it needs to create and realize its vision; to do this, it needs creativity, imagination, and knowledge, which can be obtained or enhanced through learning. This paper defines vision, learning, creativity and management and, above all, their relationships. The author argues that company vision influences the learning and knowledge of employees in the company through the vision’s content, through the vision-creating process, and through the vision enforcement process. Conversely, the influence of learning on company vision is explained. The paper is aimed at the use in the practice of companies and helps them to increase their effectiveness.

  10. Vision as subjective perception

    International Nuclear Information System (INIS)

    Reppas, J.B.; Dale, A.; Sereno, M.; Tootell, R.

    1996-01-01

    The human brain is not very different of the monkey's one: at least, its visual cortex is organized as a similar scheme. Specialized areas in the movement analysis are found and others in the forms perception. In this work, the author tries to answer to the following questions: 1)why so many visual areas? What are exactly their role in vision? Thirteen years of experimentation have not allowed to answer to these questions. The cerebral NMR imaging gives the opportunity of understanding the subjective perception of the visual world. One step which is particularly described in this work is to know how the visual cortex reacts to the optical illusions. (O.M.)

  11. Industrial robot's vision systems

    Science.gov (United States)

    Iureva, Radda A.; Raskin, Evgeni O.; Komarov, Igor I.; Maltseva, Nadezhda K.; Fedosovsky, Michael E.

    2016-03-01

    Due to the improved economic situation in the high technology sectors, work on the creation of industrial robots and special mobile robotic systems are resumed. Despite this, the robotic control systems mostly remained unchanged. Hence one can see all advantages and disadvantages of these systems. This is due to lack of funds, which could greatly facilitate the work of the operator, and in some cases, completely replace it. The paper is concerned with the complex machine vision of robotic system for monitoring of underground pipelines, which collects and analyzes up to 90% of the necessary information. Vision Systems are used to identify obstacles to the process of movement on a trajectory to determine their origin, dimensions and character. The object is illuminated in a structured light, TV camera records projected structure. Distortions of the structure uniquely determine the shape of the object in view of the camera. The reference illumination is synchronized with the camera. The main parameters of the system are the basic distance between the generator and the lights and the camera parallax angle (the angle between the optical axes of the projection unit and camera).

  12. Coherent laser vision system

    International Nuclear Information System (INIS)

    Sebastion, R.L.

    1995-01-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system

  13. Energy visions 2050

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    Energy Visions 2050 considers measures for addressing the enormous future challenges facing the energy sector, focusing on technological and techno-economic perspectives. The analysis of the development of technologies covers the whole energy chain, highlighting the necessity of efficient energy use in all activities of societies. The contents include a discussion on potential future low-emission and renewable energy conversion technologies, as well as new technology solutions in the industrial, building and transport sectors and in energy supply systems. The move towards zero-emission energy systems has consequenses for energy supply, and makes the analysis of energy resources presented in the book all the more valuable. Scenarios of alternative development paths to 2050 at the global, European and Finnish levels are presented, assuming different technological development options, economic growth rates, degrees of globalisation and information flows. The results show interesting differences between the scenarios with regard to energy production and use, mitigation of greenhouse gas emissions, and global warming. Energy Visions 2050 in mainly intended for those who have a fairly good knowledge of the energy sector and energy technologies, e.g. energy policymakers, experts responsible for energy-related issues in industry, and investors in energy technologies. The topics are approached from a global perspective. In some technological details, however, Finnish technology and Finland's technological achievements are highlighted. The topics and viewpoints of the book will certainly be of interest to international readers as well

  14. Polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Prepost, R. [Univ. of Wisconsin, Madison, WI (United States)

    1994-12-01

    The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized source are presented.

  15. Benchmarking Neuromorphic Vision: Lessons Learnt from Computer Vision

    Directory of Open Access Journals (Sweden)

    Cheston eTan

    2015-10-01

    Full Text Available Neuromorphic Vision sensors have improved greatly since the first silicon retina was presented almost three decades ago. They have recently matured to the point where they are commercially available and can be operated by laymen. However, despite improved availability of sensors, there remains a lack of good datasets, and algorithms for processing spike-based visual data are still in their infancy. On the other hand, frame-based computer vision algorithms are far more mature, thanks in part to widely accepted datasets which allow direct comparison between algorithms and encourage competition. We are presented with a unique opportunity to shape the development of Neuromorphic Vision benchmarks and challenges by leveraging what has been learnt from the use of datasets in frame-based computer vision. Taking advantage of this opportunity, in this paper we review the role that benchmarks and challenges have played in the advancement of frame-based computer vision, and suggest guidelines for the creation of Neuromorphic Vision benchmarks and challenges. We also discuss the unique challenges faced when benchmarking Neuromorphic Vision algorithms, particularly when attempting to provide direct comparison with frame-based computer vision.

  16. Near vision spectacle coverage and barriers to near vision ...

    African Journals Online (AJOL)

    Purpose: To determine the near vision spectacle coverage and barriers to obtaining near vision correction among adults aged 35 years and older in the Cape Coast Metropolis of Ghana. Methods: A population-based cross-sectional study design was adopted and 500 out of 576 participants aged 35 years and older were ...

  17. the evaluation of vision in children using monocular vision acuity ...

    African Journals Online (AJOL)

    INTRODUCTION. Monocular visual acuity (VA) is a direct method of detecting amblyopia, a leading cause of monocular vision loss in the 2 to 7years age group . Binocular vision is fully established by 6 moths of age, while fusion is consistently strengthened until the age of 6 years when it is fully developed . It was observed ...

  18. Parallel inputs to memory in bee colour vision.

    Science.gov (United States)

    Horridge, Adrian

    2016-03-01

    In the 19(th) century, it was found that attraction of bees to light was controlled by light intensity irrespective of colour, and a few critical entomologists inferred that vision of bees foraging on flowers was unlike human colour vision. Therefore, quite justly, Professor Carl von Hess concluded in his book on the Comparative Physiology of Vision (1912) that bees do not distinguish colours in the way that humans enjoy. Immediately, Karl von Frisch, an assistant in the Zoology Department of the same University of Münich, set to work to show that indeed bees have colour vision like humans, thereby initiating a new research tradition, and setting off a decade of controversy that ended only at the death of Hess in 1923. Until 1939, several researchers continued the tradition of trying to untangle the mechanism of bee vision by repeatedly testing trained bees, but made little progress, partly because von Frisch and his legacy dominated the scene. The theory of trichromatic colour vision further developed after three types of receptors sensitive to green, blue, and ultraviolet (UV), were demonstrated in 1964 in the bee. Then, until the end of the century, all data was interpreted in terms of trichromatic colour space. Anomalies were nothing new, but eventually after 1996 they led to the discovery that bees have a previously unknown type of colour vision based on a monochromatic measure and distribution of blue and measures of modulation in green and blue receptor pathways. Meanwhile, in the 20(th) century, search for a suitable rationalization, and explorations of sterile culs-de-sac had filled the literature of bee colour vision, but were based on the wrong theory.

  19. Understanding and applying machine vision

    CERN Document Server

    Zeuch, Nello

    2000-01-01

    A discussion of applications of machine vision technology in the semiconductor, electronic, automotive, wood, food, pharmaceutical, printing, and container industries. It describes systems that enable projects to move forward swiftly and efficiently, and focuses on the nuances of the engineering and system integration of machine vision technology.

  20. Vision by Man and Machine.

    Science.gov (United States)

    Poggio, Tomaso

    1984-01-01

    Studies of stereo vision guide research on how animals see and how computers might accomplish this human activity. Discusses a sequence of algorithms to first extract information from visual images and then to calculate the depths of objects in the three-dimensional world, concentrating on stereopsis (stereo vision). (JN)

  1. An overview of computer vision

    Science.gov (United States)

    Gevarter, W. B.

    1982-01-01

    An overview of computer vision is provided. Image understanding and scene analysis are emphasized, and pertinent aspects of pattern recognition are treated. The basic approach to computer vision systems, the techniques utilized, applications, the current existing systems and state-of-the-art issues and research requirements, who is doing it and who is funding it, and future trends and expectations are reviewed.

  2. Continuous learning in computer vision

    NARCIS (Netherlands)

    Pintea, S.L.

    2017-01-01

    In this thesis we focus on continuous learning, and specifically on continuous learning in the context of computer vision. Computer vision aims at interpreting the world from its visual dimension, in an automatic manner. The world in general is characterized by continuity, and so is the visual world

  3. Functional programming for computer vision

    Science.gov (United States)

    Breuel, Thomas M.

    1992-04-01

    Functional programming is a style of programming that avoids the use of side effects (like assignment) and uses functions as first class data objects. Compared with imperative programs, functional programs can be parallelized better, and provide better encapsulation, type checking, and abstractions. This is important for building and integrating large vision software systems. In the past, efficiency has been an obstacle to the application of functional programming techniques in computationally intensive areas such as computer vision. We discuss and evaluate several 'functional' data structures for representing efficiently data structures and objects common in computer vision. In particular, we will address: automatic storage allocation and reclamation issues; abstraction of control structures; efficient sequential update of large data structures; representing images as functions; and object-oriented programming. Our experience suggests that functional techniques are feasible for high- performance vision systems, and that a functional approach simplifies the implementation and integration of vision systems greatly. Examples in C++ and SML are given.

  4. 2020 Vision Project Summary

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, K.W.; Scott, K.P.

    2000-11-01

    Since the 2020 Vision project began in 1996, students from participating schools have completed and submitted a variety of scenarios describing potential world and regional conditions in the year 2020 and their possible effect on US national security. This report summarizes the students' views and describes trends observed over the course of the 2020 Vision project's five years. It also highlights the main organizational features of the project. An analysis of thematic trends among the scenarios showed interesting shifts in students' thinking, particularly in their views of computer technology, US relations with China, and globalization. In 1996, most students perceived computer technology as highly beneficial to society, but as the year 2000 approached, this technology was viewed with fear and suspicion, even personified as a malicious, uncontrollable being. Yet, after New Year's passed with little disruption, students generally again perceived computer technology as beneficial. Also in 1996, students tended to see US relations with China as potentially positive, with economic interaction proving favorable to both countries. By 2000, this view had transformed into a perception of China emerging as the US' main rival and ''enemy'' in the global geopolitical realm. Regarding globalization, students in the first two years of the project tended to perceive world events as dependent on US action. However, by the end of the project, they saw the US as having little control over world events and therefore, we Americans would need to cooperate and compromise with other nations in order to maintain our own well-being.

  5. Bio-Inspired Sensing and Imaging of Polarization Information in Nature

    Science.gov (United States)

    2008-05-04

    established that honeybees through their perception of polarized light use the Sun as a compass through their perception of the polarization pattern of... Neurobiology of polarization vision,” Trends Neu- rosci. 12, 353–359 (1989). 32. R. Wehner, “‘Matched filters’: neural models of the external world,” J... compass and odometer, Curr. Opin. Neurobiol. 12, 707–714 (2002). 48. M. Born and E. Wolf, Principles of Optics, 7th ed. (Cambridge U. Press, 2002). 49. W

  6. Computer vision for an autonomous mobile robot

    CSIR Research Space (South Africa)

    Withey, Daniel J

    2015-10-01

    Full Text Available Computer vision systems are essential for practical, autonomous, mobile robots – machines that employ artificial intelligence and control their own motion within an environment. As with biological systems, computer vision systems include the vision...

  7. A Bionic Polarization Navigation Sensor and Its Calibration Method.

    Science.gov (United States)

    Zhao, Huijie; Xu, Wujian

    2016-08-03

    The polarization patterns of skylight which arise due to the scattering of sunlight in the atmosphere can be used by many insects for deriving compass information. Inspired by insects' polarized light compass, scientists have developed a new kind of navigation method. One of the key techniques in this method is the polarimetric sensor which is used to acquire direction information from skylight. In this paper, a polarization navigation sensor is proposed which imitates the working principles of the polarization vision systems of insects. We introduce the optical design and mathematical model of the sensor. In addition, a calibration method based on variable substitution and non-linear curve fitting is proposed. The results obtained from the outdoor experiments provide support for the feasibility and precision of the sensor. The sensor's signal processing can be well described using our mathematical model. A relatively high degree of accuracy in polarization measurement can be obtained without any error compensation.

  8. Geographical Income Polarization

    DEFF Research Database (Denmark)

    Azhar, Hussain; Jonassen, Anders Bruun

    inter municipal income inequality. Counter factual simulations show that rising property prices to a large part explain the rise in polarization. One side-effect of polarization is tendencies towards a parallel polarization of residence location patterns, where low skilled individuals tend to live......In this paper we estimate the degree, composition and development of geographical income polarization based on data at the individual and municipal level in Denmark from 1984 to 2002. Rising income polarization is reconfirmed when applying new polarization measures, the driving force being greater...

  9. Machine vision for digital microfluidics.

    Science.gov (United States)

    Shin, Yong-Jun; Lee, Jeong-Bong

    2010-01-01

    Machine vision is widely used in an industrial environment today. It can perform various tasks, such as inspecting and controlling production processes, that may require humanlike intelligence. The importance of imaging technology for biological research or medical diagnosis is greater than ever. For example, fluorescent reporter imaging enables scientists to study the dynamics of gene networks with high spatial and temporal resolution. Such high-throughput imaging is increasingly demanding the use of machine vision for real-time analysis and control. Digital microfluidics is a relatively new technology with expectations of becoming a true lab-on-a-chip platform. Utilizing digital microfluidics, only small amounts of biological samples are required and the experimental procedures can be automatically controlled. There is a strong need for the development of a digital microfluidics system integrated with machine vision for innovative biological research today. In this paper, we show how machine vision can be applied to digital microfluidics by demonstrating two applications: machine vision-based measurement of the kinetics of biomolecular interactions and machine vision-based droplet motion control. It is expected that digital microfluidics-based machine vision system will add intelligence and automation to high-throughput biological imaging in the future.

  10. Polarized Light Corridor Demonstrations.

    Science.gov (United States)

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  11. Multiple visioning: new ways of constructing transnational spatial visions

    OpenAIRE

    Wil Zonneveld

    2005-01-01

    In many parts of Europe, but also at the level of the European Union and the much higher level of the Council of Europe, the creation of spatial visions is now underway. However, these spatial visions often lack an essential ingredient of spatial planning, namely maps. This omission may seem paradoxical, because maps are essential for communicating ideas with a spatial dimension. The vast spatial and political complexities at transnational and European levels are addressed by elementary proce...

  12. Polarized Moessbauer transitions

    International Nuclear Information System (INIS)

    Barb, D.

    1975-01-01

    Theoretical aspects of the emission, absorption and scattering of polarized gamma rays are reviewed for a general case of combined magnetic and electric hyperfine interactions; various possibilities of obtaining polarized gamma sources are described and examples are given of the applications of Moessbauer spectroscopy with polarized gamma rays in solving problems of solid state physics. (A.K.)

  13. Vision as a Beachhead.

    Science.gov (United States)

    Heeger, David J; Behrmann, Marlene; Dinstein, Ilan

    2017-05-15

    When neural circuits develop abnormally due to different genetic deficits and/or environmental insults, neural computations and the behaviors that rely on them are altered. Computational theories that relate neural circuits with specific quantifiable behavioral and physiological phenomena, therefore, serve as extremely useful tools for elucidating the neuropathological mechanisms that underlie different disorders. The visual system is particularly well suited for characterizing differences in neural computations; computational theories of vision are well established, and empirical protocols for measuring the parameters of those theories are well developed. In this article, we examine how psychophysical and neuroimaging measurements from human subjects are being used to test hypotheses about abnormal neural computations in autism, with an emphasis on hypotheses regarding potential excitation/inhibition imbalances. We discuss the complexity of relating specific computational abnormalities to particular underlying mechanisms given the diversity of neural circuits that can generate the same computation, and we discuss areas of research in which computational theories need to be further developed to provide useful frameworks for interpreting existing results. A final emphasis is placed on the need to extend existing ideas into developmental frameworks that take into account the dramatic developmental changes in neurophysiology (e.g., changes in excitation/inhibition balance) that take place during the first years of life, when autism initially emerges. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  14. 2020 vision for KAUST

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Felicitas Pauss, Head of International Relations at CERN, greets Members of the Board of Trustees of the King Abdullah University of Science and Technology, KAUST, who visited CERN on Friday 6 August.   Members of Board of Trustees of the King Abdullah University of Science and Technology upon their arrival at CERN. KAUST, which is situated on Saudi Arabia’s Red Sea coast, is a new, forward-looking co-educational and research university with a vision to become one of the world’s top ten science and technology Universities by 2020, stimulating the intellectual life of Saudi Arabia and making significant contributions to the country’s economy. CERN’s Director General, Rolf Heuer, is a member of the Board of Trustees. “I accepted the invitation to join the board because I believe that KAUST’s values can make a real difference to the region and to the world,” he said. The University’s mission statement emphasises achiev...

  15. Visiones de la etnicidad

    Directory of Open Access Journals (Sweden)

    MANUEL ÁNGEL RÍO RUIZ

    2002-01-01

    Full Text Available Este artículo presenta y evalúa las principales contribuciones de algunos de los estudios sobre etnicidad y relaciones étnicas en unas últimas décadas marcadas, frente a los pronósticos de diversas variantes de la teoría sociológica contemporánea, por una notable intensificación de los conflictos sociales articulados sobre lealtades y divisorias étnicas. Se exponen los avances y se identifican algunas de las lagunas y abusos que han presidido el debate entre las visiones primordialistas y construcitivistas de la etnicidad. Frente a los reduccionismos del primordialismo cultural y, tambien, de ciertas versiones encasilladas en la teoría constructivista, como los enfoques instrumentalistas radicales de la identidad étinica, se incide en la necesidad de considerar a la etnicidad como un fenómeno dual: una combinación de muchos aspectos única entre interés y adhesión primaria o afectiva, lo que dota a las asociaciones étnicas de una notable superioridad frente a otras formas de asociación colectiva como núcleo de movilización social.

  16. Electrochemical regulation of budding yeast polarity.

    Directory of Open Access Journals (Sweden)

    Armin Haupt

    2014-12-01

    Full Text Available Cells are naturally surrounded by organized electrical signals in the form of local ion fluxes, membrane potential, and electric fields (EFs at their surface. Although the contribution of electrochemical elements to cell polarity and migration is beginning to be appreciated, underlying mechanisms are not known. Here we show that an exogenous EF can orient cell polarization in budding yeast (Saccharomyces cerevisiae cells, directing the growth of mating projections towards sites of hyperpolarized membrane potential, while directing bud emergence in the opposite direction, towards sites of depolarized potential. Using an optogenetic approach, we demonstrate that a local change in membrane potential triggered by light is sufficient to direct cell polarization. Screens for mutants with altered EF responses identify genes involved in transducing electrochemical signals to the polarity machinery. Membrane potential, which is regulated by the potassium transporter Trk1p, is required for polarity orientation during mating and EF response. Membrane potential may regulate membrane charges through negatively charged phosphatidylserines (PSs, which act to position the Cdc42p-based polarity machinery. These studies thus define an electrochemical pathway that directs the orientation of cell polarization.

  17. The Economics of VISION 2020

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. The Economics of VISION 2020. Blindness adds to individual, family and community poverty. The interventions for 80% of Blinding Diseases are very effective. The interventions are inexpensive. Notes:

  18. Strategic Vision: A Selected Bibliography

    National Research Council Canada - National Science Library

    Moyer, Jeannette

    2008-01-01

    Strategic Vision is an enduring theme at the U.S. Army War College. Compiled in support of this theme, this selected bibliography reflects books, documents, periodical articles, and a number of web sites...

  19. Computer Vision for Timber Harvesting

    DEFF Research Database (Denmark)

    Dahl, Anders Lindbjerg

    The goal of this thesis is to investigate computer vision methods for timber harvesting operations. The background for developing computer vision for timber harvesting is to document origin of timber and to collect qualitative and quantitative parameters concerning the timber for efficient harvest...... segments. The purpose of image segmentation is to make the basis for more advanced computer vision methods like object recognition and classification. Our second method concerns image classification and we present a method where we classify small timber samples to tree species based on Active Appearance...... to the development of the logTracker system the described methods have a general applicability making them useful for many other computer vision problems....

  20. Nanomedical device and systems design challenges, possibilities, visions

    CERN Document Server

    2014-01-01

    Nanomedical Device and Systems Design: Challenges, Possibilities, Visions serves as a preliminary guide toward the inspiration of specific investigative pathways that may lead to meaningful discourse and significant advances in nanomedicine/nanotechnology. This volume considers the potential of future innovations that will involve nanomedical devices and systems. It endeavors to explore remarkable possibilities spanning medical diagnostics, therapeutics, and other advancements that may be enabled within this discipline. In particular, this book investigates just how nanomedical diagnostic and

  1. Aircraft cockpit vision: Math model

    Science.gov (United States)

    Bashir, J.; Singh, R. P.

    1975-01-01

    A mathematical model was developed to describe the field of vision of a pilot seated in an aircraft. Given the position and orientation of the aircraft, along with the geometrical configuration of its windows, and the location of an object, the model determines whether the object would be within the pilot's external vision envelope provided by the aircraft's windows. The computer program using this model was implemented and is described.

  2. [Acquired disorders of color vision].

    Science.gov (United States)

    Lascu, Lidia; Balaş, Mihaela

    2002-01-01

    This article is a general view of acquired disorders of color vision. The revision of the best known methods and of the etiopathogenic classification is not very important in ophthalmology but on the other hand, the detection of the blue defect advertise and associated ocular pathology. There is a major interest in serious diseases as multiple sclerosis, AIDS, diabetes melitus, when the first ocular sign can be a defect in the color vision.

  3. Artificial intelligence and computer vision

    CERN Document Server

    Li, Yujie

    2017-01-01

    This edited book presents essential findings in the research fields of artificial intelligence and computer vision, with a primary focus on new research ideas and results for mathematical problems involved in computer vision systems. The book provides an international forum for researchers to summarize the most recent developments and ideas in the field, with a special emphasis on the technical and observational results obtained in the past few years.

  4. Pathway Graphical Lasso

    Science.gov (United States)

    Grechkin, Maxim; Fazel, Maryam; Witten, Daniela; Lee, Su-In

    2014-01-01

    Graphical models provide a rich framework for summarizing the dependencies among variables. The graphical lasso approach attempts to learn the structure of a Gaussian graphical model (GGM) by maximizing the log likelihood of the data, subject to an l1 penalty on the elements of the inverse co-variance matrix. Most algorithms for solving the graphical lasso problem do not scale to a very large number of variables. Furthermore, the learned network structure is hard to interpret. To overcome these challenges, we propose a novel GGM structure learning method that exploits the fact that for many real-world problems we have prior knowledge that certain edges are unlikely to be present. For example, in gene regulatory networks, a pair of genes that does not participate together in any of the cellular processes, typically referred to as pathways, is less likely to be connected. In computer vision applications in which each variable corresponds to a pixel, each variable is likely to be connected to the nearby variables. In this paper, we propose the pathway graphical lasso, which learns the structure of a GGM subject to pathway-based constraints. In order to solve this problem, we decompose the network into smaller parts, and use a message-passing algorithm in order to communicate among the subnetworks. Our algorithm has orders of magnitude improvement in run time compared to the state-of-the-art optimization methods for the graphical lasso problem that were modified to handle pathway-based constraints. PMID:26167394

  5. Hydropower Vision: Full Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-07-01

    Hydropower has provided clean, affordable, reliable, and renewable electricity in the United States for more than a century. Building on hydropower’s historical significance, and to inform the continued technical evolution, energy market value, and environmental performance of the industry, the U.S. Department of Energy’s (DOE’s) Wind and Water Power Technologies Office has led a first-of-its-kind comprehensive analysis focused on a set of potential pathways for the environmentally sustainable expansion of hydropower (hydropower generation and pumped storage) in the United States.

  6. The Polarized Radiation Imaging and Spectroscopy Mission

    CERN Document Server

    André, Philippe; Banday, Anthony; Barbosa, Domingos; Barreiro, Belen; Bartlett, James; Bartolo, Nicola; Battistelli, Elia; Battye, Richard; Bendo, George; Benoȋt, Alain; Bernard, Jean-Philippe; Bersanelli, Marco; Béthermin, Matthieu; Bielewicz, Pawel; Bonaldi, Anna; Bouchet, François; Boulanger, François; Brand, Jan; Bucher, Martin; Burigana, Carlo; Cai, Zhen-Yi; Camus, Philippe; Casas, Francisco; Casasola, Viviana; Castex, Guillaume; Challinor, Anthony; Chluba, Jens; Chon, Gayoung; Colafrancesco, Sergio; Comis, Barbara; Cuttaia, Francesco; D'Alessandro, Giuseppe; Da Silva, Antonio; Davis, Richard; de Avillez, Miguel; de Bernardis, Paolo; de Petris, Marco; de Rosa, Adriano; de Zotti, Gianfranco; Delabrouille, Jacques; Désert, François-Xavier; Dickinson, Clive; Diego, Jose Maria; Dunkley, Joanna; Enßlin, Torsten; Errard, Josquin; Falgarone, Edith; Ferreira, Pedro; Ferrière, Katia; Finelli, Fabio; Fletcher, Andrew; Fosalba, Pablo; Fuller, Gary; Galli, Silvia; Ganga, Ken; García-Bellido, Juan; Ghribi, Adnan; Giard, Martin; Giraud-Héraud, Yannick; Gonzalez-Nuevo, Joaquin; Grainge, Keith; Gruppuso, Alessandro; Hall, Alex; Hamilton, Jean-Christophe; Haverkorn, Marijke; Hernandez-Monteagudo, Carlos; Herranz, Diego; Jackson, Mark; Jaffe, Andrew; Khatri, Rishi; Kunz, Martin; Lamagna, Luca; Lattanzi, Massimiliano; Leahy, Paddy; Lesgourgues, Julien; Liguori, Michele; Liuzzo, Elisabetta; Lopez-Caniego, Marcos; Macias-Perez, Juan; Maffei, Bruno; Maino, Davide; Mangilli, Anna; Martinez-Gonzalez, Enrique; Martins, Carlos J.A.P.; Masi, Silvia; Massardi, Marcella; Matarrese, Sabino; Melchiorri, Alessandro; Melin, Jean-Baptiste; Mennella, Aniello; Mignano, Arturo; Miville-Deschênes, Marc-Antoine; Monfardini, Alessandro; Murphy, Anthony; Naselsky, Pavel; Nati, Federico; Natoli, Paolo; Negrello, Mattia; Noviello, Fabio; O'Sullivan, Créidhe; Paci, Francesco; Pagano, Luca; Paladino, Rosita; Palanque-Delabrouille, Nathalie; Paoletti, Daniela; Peiris, Hiranya; Perrotta, Francesca; Piacentini, Francesco; Piat, Michel; Piccirillo, Lucio; Pisano, Giampaolo; Polenta, Gianluca; Pollo, Agnieszka; Ponthieu, Nicolas; Remazeilles, Mathieu; Ricciardi, Sara; Roman, Matthieu; Rosset, Cyrille; Rubino-Martin, Jose-Alberto; Salatino, Maria; Schillaci, Alessandro; Shellard, Paul; Silk, Joseph; Starobinsky, Alexei; Stompor, Radek; Sunyaev, Rashid; Tartari, Andrea; Terenzi, Luca; Toffolatti, Luigi; Tomasi, Maurizio; Trappe, Neil; Tristram, Matthieu; Trombetti, Tiziana; Tucci, Marco; Van de Weijgaert, Rien; Van Tent, Bartjan; Verde, Licia; Vielva, Patricio; Wandelt, Ben; Watson, Robert; Withington, Stafford; Cabrera, Nicolas

    2014-01-01

    PRISM (Polarized Radiation Imaging and Spectroscopy Mission) was proposed to ESA in May 2013 as a large-class mission for investigating within the framework of the ESA Cosmic Vision program a set of important scientific questions that require high resolution, high sensitivity, full-sky observations of the sky emission at wavelengths ranging from millimeter-wave to the far-infrared. PRISM's main objective is to explore the distant universe, probing cosmic history from very early times until now as well as the structures, distribution of matter, and velocity flows throughout our Hubble volume. PRISM will survey the full sky in a large number of frequency bands in both intensity and polarization and will measure the absolute spectrum of sky emission more than three orders of magnitude better than COBE FIRAS. The aim of this Extended White Paper is to provide a more detailed overview of the highlights of the new science that will be made possible by PRISM

  7. Machine Learning for Computer Vision

    CERN Document Server

    Battiato, Sebastiano; Farinella, Giovanni

    2013-01-01

    Computer vision is the science and technology of making machines that see. It is concerned with the theory, design and implementation of algorithms that can automatically process visual data to recognize objects, track and recover their shape and spatial layout. The International Computer Vision Summer School - ICVSS was established in 2007 to provide both an objective and clear overview and an in-depth analysis of the state-of-the-art research in Computer Vision. The courses are delivered by world renowned experts in the field, from both academia and industry, and cover both theoretical and practical aspects of real Computer Vision problems. The school is organized every year by University of Cambridge (Computer Vision and Robotics Group) and University of Catania (Image Processing Lab). Different topics are covered each year. A summary of the past Computer Vision Summer Schools can be found at: http://www.dmi.unict.it/icvss This edited volume contains a selection of articles covering some of the talks and t...

  8. View How Glaucoma May Affect Vision

    Science.gov (United States)

    ... inbox. Sign up View How Glaucoma May Affect Vision Normal Vision This is an example of normal vision. This is also an example of how someone ... gradual and often imperceptible failing of side (peripheral) vision. Intermediate Glaucoma As glaucoma progresses, the center of ...

  9. The Physics of Polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    2015-10-01

    The introductory lecture that has been delivered at this Symposium is a condensed version of an extended course held by the author at the XII Canary Island Winter School from November 13 to November 21, 2000. The full series of lectures can be found in Landi Degl'Innocenti (2002). The original reference is organized in 20 Sections that are here itemized: 1. Introduction, 2. Description of polarized radiation, 3. Polarization and optical devices: Jones calculus and Muller matrices, 4. The Fresnel equations, 5. Dichroism and anomalous dispersion, 6. Polarization in everyday life, 7. Polarization due to radiating charges, 8. The linear antenna, 9. Thomson scattering, 10. Rayleigh scattering, 11. A digression on Mie scattering, 12. Bremsstrahlung radiation, 13. Cyclotron radiation, 14. Synchrotron radiation, 15. Polarization in spectral lines, 16. Density matrix and atomic polarization, 17. Radiative transfer and statistical equilibrium equations, 18. The amplification condition in polarized radiative transfer, and 19. Coupling radiative transfer and statistical equilibrium equations.

  10. Evolutionary replacement of UV vision by violet vision in fish

    Science.gov (United States)

    Tada, Takashi; Altun, Ahmet; Yokoyama, Shozo

    2009-01-01

    The vertebrate ancestor possessed ultraviolet (UV) vision and many species have retained it during evolution. Many other species switched to violet vision and, then again, some avian species switched back to UV vision. These UV and violet vision are mediated by short wavelength-sensitive (SWS1) pigments that absorb light maximally (λmax) at approximately 360 and 390–440 nm, respectively. It is not well understood why and how these functional changes have occurred. Here, we cloned the pigment of scabbardfish (Lepidopus fitchi) with a λmax of 423 nm, an example of violet-sensitive SWS1 pigment in fish. Mutagenesis experiments and quantum mechanical/molecular mechanical (QM/MM) computations show that the violet-sensitivity was achieved by the deletion of Phe-86 that converted the unprotonated Schiff base-linked 11-cis-retinal to a protonated form. The finding of a violet-sensitive SWS1 pigment in scabbardfish suggests that many other fish also have orthologous violet pigments. The isolation and comparison of such violet and UV pigments in fish living in different ecological habitats will open an unprecedented opportunity to elucidate not only the molecular basis of phenotypic adaptations, but also the genetics of UV and violet vision. PMID:19805066

  11. Experimental simulation of simultaneous vision.

    Science.gov (United States)

    de Gracia, Pablo; Dorronsoro, Carlos; Sánchez-González, Álvaro; Sawides, Lucie; Marcos, Susana

    2013-01-17

    To present and validate a prototype of an optical instrument that allows experimental simulation of pure bifocal vision. To evaluate the influence of different power additions on image contrast and visual acuity. The instrument provides the eye with two superimposed images, aligned and with the same magnification, but with different defocus states. Subjects looking through the instrument are able to experience pure simultaneous vision, with adjustable refractive correction and addition power. The instrument is used to investigate the impact of the amount of addition of an ideal bifocal simultaneous vision correction, both on image contrast and on visual performance. the instrument is validated through computer simulations of the letter contrast and by equivalent optical experiments with an artificial eye (camera). Visual acuity (VA) was measured in four subjects (AGE: 34.3 ± 3.4 years; spherical error: -2.1 ± 2.7 diopters [D]) for low and high contrast letters and different amounts of addition. The largest degradation in contrast and visual acuity (∼25%) occurred for additions around ±2 D, while additions of ±4 D produced lower degradation (14%). Low additions (1-2 D) result in lower VA than high additions (3-4 D). A simultaneous vision instrument is an excellent tool to simulate bifocal vision and to gain understanding of multifocal solutions for presbyopia. Simultaneous vision induces a pattern of visual performance degradation, which is well predicted by the degradation found in image quality. Neural effects, claimed to be crucial in the patients' tolerance of simultaneous vision, can be therefore compared with pure optical effects.

  12. Do cephalopods communicate using polarized light reflections from their skin?

    Science.gov (United States)

    Mäthger, Lydia M; Shashar, Nadav; Hanlon, Roger T

    2009-07-01

    Cephalopods (squid, cuttlefish and octopus) are probably best known for their ability to change color and pattern for camouflage and communication. This is made possible by their complex skin, which contains pigmented chromatophore organs and structural light reflectors (iridophores and leucophores). Iridophores create colorful and linearly polarized reflective patterns. Equally interesting, the photoreceptors of cephalopod eyes are arranged in a way to give these animals the ability to detect the linear polarization of incoming light. The capacity to detect polarized light may have a variety of functions, such as prey detection, navigation, orientation and contrast enhancement. Because the skin of cephalopods can produce polarized reflective patterns, it has been postulated that cephalopods could communicate intraspecifically through this visual system. The term 'hidden' or 'private' communication channel has been given to this concept because many cephalopod predators may not be able to see their polarized reflective patterns. We review the evidence for polarization vision as well as polarization signaling in some cephalopod species and provide examples that tend to support the notion--currently unproven--that some cephalopods communicate using polarized light signals.

  13. Modeling Population-Level Consequences of Polychlorinated Biphenyl Exposure in East Greenland Polar Bears.

    Science.gov (United States)

    Pavlova, Viola; Grimm, Volker; Dietz, Rune; Sonne, Christian; Vorkamp, Katrin; Rigét, Frank F; Letcher, Robert J; Gustavson, Kim; Desforges, Jean-Pierre; Nabe-Nielsen, Jacob

    2016-01-01

    Polychlorinated biphenyls (PCBs) can cause endocrine disruption, cancer, immunosuppression, or reproductive failure in animals. We used an individual-based model to explore whether and how PCB-associated reproductive failure could affect the dynamics of a hypothetical polar bear (Ursus maritimus) population exposed to PCBs to the same degree as the East Greenland subpopulation. Dose-response data from experimental studies on a surrogate species, the mink (Mustela vision), were used in the absence of similar data for polar bears. Two alternative types of reproductive failure in relation to maternal sum-PCB concentrations were considered: increased abortion rate and increased cub mortality. We found that the quantitative impact of PCB-induced reproductive failure on population growth rate depended largely on the actual type of reproductive failure involved. Critical potencies of the dose-response relationship for decreasing the population growth rate were established for both modeled types of reproductive failure. Comparing the model predictions of the age-dependent trend of sum-PCBs concentrations in females with actual field measurements from East Greenland indicated that it was unlikely that PCB exposure caused a high incidence of abortions in the subpopulation. However, on the basis of this analysis, it could not be excluded that PCB exposure contributes to higher cub mortality. Our results highlight the necessity for further research on the possible influence of PCBs on polar bear reproduction regarding their physiological pathway. This includes determining the exact cause of reproductive failure, i.e., in utero exposure versus lactational exposure of offspring; the timing of offspring death; and establishing the most relevant reference metrics for the dose-response relationship.

  14. [Review] Polarization and Polarimetry

    Science.gov (United States)

    Trippe, Sascha

    2014-02-01

    Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible multiple astrophysical discoveries. In this article I review (i) the physical basics of polarization: electromagnetic waves, photons, and parameterizations; (ii) astrophysical sources of polarization: scattering, synchrotron radiation, active media, and the Zeeman, Goldreich-Kylafis, and Hanle effects, as well as interactions between polarization and matter (like birefringence, Faraday rotation, or the Chandrasekhar-Fermi effect); (iii) observational methodology: on-sky geometry, influence of atmosphere and instrumental polarization, polarization statistics, and observational techniques for radio, optical, and X/γ wavelengths; and (iv) science cases for astronomical polarimetry: solar and stellar physics, planetary system bodies, interstellar matter, astrobiology, astronomical masers, pulsars, galactic magnetic fields, gamma-ray bursts, active galactic nuclei, and cosmic microwave background radiation.

  15. Polarization feedback laser stabilization

    Science.gov (United States)

    Esherick, P.; Owyoung, A.

    1987-09-28

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

  16. Polarization in Sagittarius A*

    OpenAIRE

    Bower, Geoffrey C.

    2000-01-01

    We summarize the current state of polarization observations of Sagittarius A*, the compact radio source and supermassive black hole candidate in the Galactic Center. These observations are providing new tools for understanding accretion disks, jets and their environments. Linear polarization observations have shown that Sgr A* is unpolarized at frequencies as high as 86 GHz. However, recent single-dish observations indicate that Sgr A* may have strong linear polarization at frequencies higher...

  17. Airborne Laser Polarization Sensor

    Science.gov (United States)

    Kalshoven, James, Jr.; Dabney, Philip

    1991-01-01

    Instrument measures polarization characteristics of Earth at three wavelengths. Airborne Laser Polarization Sensor (ALPS) measures optical polarization characteristics of land surface. Designed to be flown at altitudes of approximately 300 m to minimize any polarizing or depolarizing effects of intervening atmosphere and to look along nadir to minimize any effects depending on look angle. Data from measurements used in conjunction with data from ground surveys and aircraft-mounted video recorders to refine mathematical models used in interpretation of higher-altitude polarimetric measurements of reflected sunlight.

  18. Polarization at SLC

    International Nuclear Information System (INIS)

    Swartz, M.L.

    1988-07-01

    The SLAC Linear Collider has been designed to readily accommodate polarized electron beams. Considerable effort has been made to implement a polarized source, a spin rotation system, and a system to monitor the beam polarization. Nearly all major components have been fabricated. At the current time, several source and polarimeter components have been installed. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. It is expected that a beam polarization of 45% will be achieved with no loss in luminosity. 13 refs., 15 figs

  19. Low Vision Rehabilitation and Diabetic Retinopathy

    International Nuclear Information System (INIS)

    Khan, Sarfaraz A.

    2007-01-01

    Diabetic retinopathy is emerging as a major cause of blindness. Diabetic retinopathy calls for a multidisciplinary to the patients. Management of the patient requires a team work by the internist, diabetologist, dietician, ophthalmologist and low vision therapist. Diabetic retinopathy very often results in vision loss. It is important for ophthalmologist to recognize the importance of low vision rehabilitation in formulating appropriate treatment strategies. People with low vision loss due to diabetic retinopathy usually experience difficulty in daily life. Most people with diabetic retinopathy (who have remaining useful vision) can be helped with low vision devices. However, often one low vision device may not be suitable for all purposes. A comprehensive low vision evaluation is required to assess the person's current visual status, identify the goals and the visual needs, and then design an individualized vision rehabilitation program to meet these needs. (author)

  20. Robotic vision. [process control applications

    Science.gov (United States)

    Williams, D. S.; Wilf, J. M.; Cunningham, R. T.; Eskenazi, R.

    1979-01-01

    Robotic vision, involving the use of a vision system to control a process, is discussed. Design and selection of active sensors employing radiation of radio waves, sound waves, and laser light, respectively, to light up unobservable features in the scene are considered, as are design and selection of passive sensors, which rely on external sources of illumination. The segmentation technique by which an image is separated into different collections of contiguous picture elements having such common characteristics as color, brightness, or texture is examined, with emphasis on the edge detection technique. The IMFEX (image feature extractor) system performing edge detection and thresholding at 30 frames/sec television frame rates is described. The template matching and discrimination approach to recognize objects are noted. Applications of robotic vision in industry for tasks too monotonous or too dangerous for the workers are mentioned.

  1. Return of the Vision Video

    DEFF Research Database (Denmark)

    Vistisen, Peter; Poulsen, Søren Bolvig

    2017-01-01

    This paper examines the role of corporate vision videos as a possible setting for participation when exploring the future potentials (and pitfalls) of new technological concepts. We propose that through the recent decade’s rise web 2.0 platforms, and the viral effects of user sharing, the corporate...... vision video of today might take on a significantly different role than before, and act as a participatory design approach. This address the changing landscaping for participatory and user-involved design processes, in the wake of new digital forms of participation, communication and collaboration, which...... have radically changed the possible power dynamics of the production life cycle of new product developments. Through a case study, we pose the question of whether the online engagements around corporate vision videos can be viewed as a form of participation in a design process, and thus revitalize...

  2. Vision par ordinateur: outils fondamentaux

    OpenAIRE

    Horaud, Radu; Monga, Olivier

    1995-01-01

    National audience; Cet ouvrage présente les outils fondamentaux de la vision par ordinateur dans un langage mathématique accessible aux étudiants de niveau DEUG en mathématiques ou informatique. Il donne également de nombreux exemples d'utilisation de la vision par ordinateur dans deux domaines de technologie de pointe : la robotique et l'imagerie médicale. Cette deuxième édition largement augmentée est un manuel de référence. Les outils fondamentaux sont présentés dans un langage mathématiqu...

  3. Advances in embedded computer vision

    CERN Document Server

    Kisacanin, Branislav

    2014-01-01

    This illuminating collection offers a fresh look at the very latest advances in the field of embedded computer vision. Emerging areas covered by this comprehensive text/reference include the embedded realization of 3D vision technologies for a variety of applications, such as stereo cameras on mobile devices. Recent trends towards the development of small unmanned aerial vehicles (UAVs) with embedded image and video processing algorithms are also examined. The authoritative insights range from historical perspectives to future developments, reviewing embedded implementation, tools, technolog

  4. RHIC Polarized proton operation

    International Nuclear Information System (INIS)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D'Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.E.; Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-01-01

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP 4 . A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  5. RHIC Polarized proton operation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D' Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R,; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; J.; Severino, F.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J. Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-03-28

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP{sup 4}. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  6. Our Polar Past

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2009-01-01

    The study of polar exploration is fascinating and offers students insights into the history, culture, and politics that affect the developing sciences at the farthest ends of Earth. Therefore, the authors think there is value in incorporating polar exploration accounts within modern science classrooms, and so they conducted research to test their…

  7. Terahertz polarization imaging

    NARCIS (Netherlands)

    Van der Valk, N.C.J.; Van der Marel, W.A.M.; Planken, P.C.M.

    2005-01-01

    We present a new method to measure the polarization state of a terahertz pulse by using a modified electrooptic sampling setup. To illustrate the power of this method, we show two examples in which the knowledge of the polarization of the terahertz pulse is essential for interpreting the results:

  8. Polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    The acceleration of polarized proton beams in circular accelerators is complicated by the presence of numerous depolarizing spin resonances. Careful and tedious minimization of polarization loss at each of these resonances allowed acceleration of polarized proton beams up to 22 GeV. It has been the hope that Siberian Snakes, which are local spin rotators inserted into ring accelerators, would eliminate these resonances and allow acceleration of polarized beams with the same ease and efficiency that is now routine for unpolarized beams. First tests at IUCF with a full Siberian Snake showed that the spin dynamics with a Snake can be understood in detail. The author now has results of the first tests of a partial Siberian Snake at the AGS, accelerating polarized protons to an energy of about 25 GeV. These successful tests of storage and acceleration of polarized proton beams open up new possibilities such as stored polarized beams for internal target experiments and high energy polarized proton colliders

  9. Polar Science Is Cool!

    Science.gov (United States)

    Weeks, Sophie

    2012-01-01

    Children are fascinated by the fact that polar scientists do research in extremely cold and dangerous places. In the Arctic they might be viewed as lunch by a polar bear. In the Antarctic, they could lose toes and fingers to frostbite and the wind is so fast it can rip skin off. They camp on ice in continuous daylight, weeks from any form of…

  10. Review: Familiarity to Vision Rehabilitation Process

    Directory of Open Access Journals (Sweden)

    Nasser Sadegh-Pour

    2006-10-01

    Full Text Available Considering the numbers of low vision patients who have been visited and treated in eye clinics, sometimes there is no exact treatment to increase their visual acuity. Therefore, the necessity to pay attention to vision rehabilitation for them is strongly felt. The aims of this essay are to define vision rehabilitation and its process in relevant centers (called Low Vision Clinic.The statistic of low vision people is reported and the method of collecting data is described. Standard definition, causes of low vision and related diseases (congenital, heredity, acquired… are explained. In addition, low vision aids and role of test and prescription are discussed. Sometimes ophthalmologists and optometrists can not exactly cure patient to raise their V.A because there is no treatment or drug or ordinary glasses. In these cases the clients should refer to low vision clinic and visit low vision specialist on vision rehabilitation process. After primary evaluation they are tested completely and at the end are prescribed proper low vision aid and also provided with advice in relation to career, education role and training techniques especially in children. At the last part of present dissertation, some examples are provided to show effectiveness of vision rehabilitation and low vision aid among the clients in different countries.

  11. Visions of Discovery

    Science.gov (United States)

    Chiao, Raymond Y.; Cohen, Marvin L.; Leggett, Anthony J.; Phillips, William D.; Harper, Charles L., Jr.

    2010-10-01

    List of contributors; Foreword Charles H. Townes; Editors' preface; Preface Freeman J. Dyson; Laureates' preface: reflections from four physics Nobelists Roy J. Glauber, John L. Hall, Theodore W. Hänsch and Wolfgang Ketterle; Acknowledgments; Part I. Illumination: The History and Future of Physical Science and Technology: 1. A short history of light in the Western world John L. Heilbron; 2. Tools and innovation Peter L. Galison; 3. The future of science Freeman J. Dyson; 4. The end of everything: will AI replace humans? Will everything die when the universe freezes over? Michio Kaku; Part II. Fundamental Physics and Quantum Mechanics: 5. Fundamental constants Frank Wilczek; 6. New insights on time symmetry in quantum mechanics Yakir Aharonov and Jeffrey Tollaksen; 7. The major unknowns in particle physics and cosmology David J. Gross; 8. The major unknown in quantum mechanics: Is it the whole truth? Anthony J. Leggett; 9. Precision cosmology and the landscape Raphael Bousso; 10. Hairy black holes, phase transitions, and AdS/CFT Steven S. Gubser; Part III. Astrophysics and Astronomy: 11. The microwave background: a cosmic time machine Adrian T. Lee; 12. Dark matter and dark energy Marc Kamionkowski; 13. New directions and intersections for observational cosmology: the case of dark energy Saul Perlmutter; 14. Inward bound: high-resolution astronomy and the quest for black holes and extrasolar planets Reinhard Genzel; 15. Searching for signatures of life beyond the solar system: astrophysical interferometry and the 150 km Exo-Earth Imager Antoine Labeyrie; 16. New directions for gravitational wave physics via 'Millikan oil drops' Raymond Y. Chiao; 17. An 'ultrasonic' image of the embryonic universe: CMB polarization tests of the inflationary paradigm Brian G. Keating; Part IV. New Approaches in Technology and Science: 18. Visualizing complexity: development of 4D microscopy and diffraction for imaging in space and time Ahmed H. Zewail; 19. Is life based on laws of

  12. Precision Polarization of Neutrons

    Science.gov (United States)

    Martin, Elise; Barron-Palos, Libertad; Couture, Aaron; Crawford, Christopher; Chupp, Tim; Danagoulian, Areg; Estes, Mary; Hona, Binita; Jones, Gordon; Klein, Andi; Penttila, Seppo; Sharma, Monisha; Wilburn, Scott

    2009-05-01

    Determining polarization of a cold neutron beam to high precision is required for the next generation neutron decay correlation experiments at the SNS, such as the proposed abBA and PANDA experiments. Precision polarimetry measurements were conducted at Los Alamos National Laboratory with the goal of determining the beam polarization to the level of 10-3 or better. The cold neutrons from FP12 were polarized using optically polarized ^3He gas as a spin filter, which has a highly spin-dependent absorption cross section. A second ^ 3He spin filter was used to analyze the neutron polarization after passing through a resonant RF spin rotator. A discussion of the experiment and results will be given.

  13. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2018-01-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements. PMID:29503479

  14. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2017-10-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

  15. Parallel Polarization State Generation.

    Science.gov (United States)

    She, Alan; Capasso, Federico

    2016-05-17

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.

  16. Central Brain Circuitry for Color-Vision-Modulated Behaviors.

    Science.gov (United States)

    Longden, Kit D

    2016-10-24

    Color is famous for not existing in the external world: our brains create the perception of color from the spatial and temporal patterns of the wavelength and intensity of light. For an intangible quality, we have detailed knowledge of its origins and consequences. Much is known about the organization and evolution of the first phases of color processing, the filtering of light in the eye and processing in the retina, and about the final phases, the roles of color in behavior and natural selection. To understand how color processing in the central brain has evolved, we need well-defined pathways or circuitry where we can gauge how color contributes to the computations involved in specific behaviors. Examples of such pathways or circuitry that are dedicated to processing color cues are rare, despite the separation of color and luminance pathways early in the visual system of many species, and despite the traditional definition of color as being independent of luminance. This minireview presents examples in which color vision contributes to behaviors dominated by other visual modalities, examples that are not part of the canon of color vision circuitry. The pathways and circuitry process a range of chromatic properties of objects and their illumination, and are taken from a variety of species. By considering how color processing complements luminance processing, rather than being independent of it, we gain an additional way to account for the diversity of color coding in the central brain, its consequences for specific behaviors and ultimately the evolution of color vision. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Building AN International Polar Data Coordination Network

    Science.gov (United States)

    Pulsifer, P. L.; Yarmey, L.; Manley, W. F.; Gaylord, A. G.; Tweedie, C. E.

    2013-12-01

    In the spirit of the World Data Center system developed to manage data resulting from the International Geophysical Year of 1957-58, the International Polar Year 2007-2009 (IPY) resulted in significant progress towards establishing an international polar data management network. However, a sustained international network is still evolving. In this paper we argue that the fundamental building blocks for such a network exist and that the time is right to move forward. We focus on the Arctic component of such a network with linkages to Antarctic network building activities. A review of an important set of Network building blocks is presented: i) the legacy of the IPY data and information service; ii) global data management services with a polar component (e.g. World Data System); iii) regional systems (e.g. Arctic Observing Viewer; iv) nationally focused programs (e.g. Arctic Observing Viewer, Advanced Cooperative Arctic Data and Information Service, Polar Data Catalogue, Inuit Knowledge Centre); v) programs focused on the local (e.g. Exchange for Local Observations and Knowledge of the Arctic, Geomatics and Cartographic Research Centre). We discuss current activities and results with respect to three priority areas needed to establish a strong and effective Network. First, a summary of network building activities reports on a series of productive meetings, including the Arctic Observing Summit and the Polar Data Forum, that have resulted in a core set of Network nodes and participants and a refined vision for the Network. Second, we recognize that interoperability for information sharing fundamentally relies on the creation and adoption of community-based data description standards and data delivery mechanisms. There is a broad range of interoperability frameworks and specifications available; however, these need to be adapted for polar community needs. Progress towards Network interoperability is reviewed, and a prototype distributed data systems is demonstrated. We

  18. Visions of Vision: An Exploratory Study of the Role College and University Presidents Play in Developing Institutional Vision

    Science.gov (United States)

    McWade, Jessica C.

    2014-01-01

    This qualitative research explores how college and university presidents engage in the process of developing formal institutional vision. The inquiry identifies roles presidents play in vision development, which is often undertaken as part of strategic-planning initiatives. Two constructs of leadership and institutional vision are used to examine…

  19. Chandra's X-ray Vision

    Indian Academy of Sciences (India)

    1999-07-23

    Jul 23, 1999 ... GENERAL I ARTICLE. Chandra's X-ray Vision. K P Singh. Chandra X-ray Observatory (CXO) is a scientific satellite (moon/ chandra), named after the Indian-born Nobel laureate. Subrahmanyan Chandrasekhar - one of the foremost astro- physicists of the twentieth century and popularly known as. Chandra.

  20. Frame Rate and Human Vision

    Science.gov (United States)

    Watson, Andrew B.

    2012-01-01

    To enhance the quality of the theatre experience, the film industry is interested in achieving higher frame rates for capture and display. In this talk I will describe the basic spatio-temporal sensitivities of human vision, and how they respond to the time sequence of static images that is fundamental to cinematic presentation.

  1. Real-time vision systems

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.; Hernandez, J.E.; Lu, Shin-yee [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Many industrial and defence applications require an ability to make instantaneous decisions based on sensor input of a time varying process. Such systems are referred to as `real-time systems` because they process and act on data as it occurs in time. When a vision sensor is used in a real-time system, the processing demands can be quite substantial, with typical data rates of 10-20 million samples per second. A real-time Machine Vision Laboratory (MVL) was established in FY94 to extend our years of experience in developing computer vision algorithms to include the development and implementation of real-time vision systems. The laboratory is equipped with a variety of hardware components, including Datacube image acquisition and processing boards, a Sun workstation, and several different types of CCD cameras, including monochrome and color area cameras and analog and digital line-scan cameras. The equipment is reconfigurable for prototyping different applications. This facility has been used to support several programs at LLNL, including O Division`s Peacemaker and Deadeye Projects as well as the CRADA with the U.S. Textile Industry, CAFE (Computer Aided Fabric Inspection). To date, we have successfully demonstrated several real-time applications: bullet tracking, stereo tracking and ranging, and web inspection. This work has been documented in the ongoing development of a real-time software library.

  2. SOFIA Update and Science Vision

    Science.gov (United States)

    Smith, Kimberly

    2017-01-01

    I will present an overview of the SOFIA program, its science vision and upcoming plans for the observatory. The talk will feature several scientific highlights since full operations, along with summaries of planned science observations for this coming year, platform enhancements and new instrumentation.

  3. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused

  4. Computer vision for ambient intelligence

    NARCIS (Netherlands)

    Salah, A.A.; Gevers, T.; Sebe, N.; Vinciarelli, A.

    2011-01-01

    A natural way of conceptualizing ambient intelligence is by picturing an active environment with access to perceptual input, not via eyes and ears, but by their technological counterparts. Computer vision is an essential part of building context-aware environments that adapt and anticipate their

  5. Computer Vision and Mathematical Morphology

    NARCIS (Netherlands)

    Roerdink, J.B.T.M.; Kropratsch, W.; Klette, R.; Albrecht, R.

    1996-01-01

    Mathematical morphology is a theory of set mappings, modeling binary image transformations, which are invariant under the group of Euclidean translations. This framework turns out to be too restricted for many applications, in particular for computer vision where group theoretical considerations

  6. Vision - Gateway to the brain

    CERN Multimedia

    1999-01-01

    Is the brain the result of (evolutionary) tinkering, or is it governed by natural law? How can we objectively know? What is the nature of consciousness? Vision research is spear-heading the quest and is making rapid progress with the help of new experimental, computational and theoretical tools. At the same time it is about to lead to important technical applications.

  7. Computer vision and machine learning for archaeology

    NARCIS (Netherlands)

    van der Maaten, L.J.P.; Boon, P.; Lange, G.; Paijmans, J.J.; Postma, E.

    2006-01-01

    Until now, computer vision and machine learning techniques barely contributed to the archaeological domain. The use of these techniques can support archaeologists in their assessment and classification of archaeological finds. The paper illustrates the use of computer vision techniques for

  8. Autonomous Robotic Following Using Vision Based Techniques

    National Research Council Canada - National Science Library

    Kania, Robert T; Frederick, Phil A; Del Rose, Mike

    2006-01-01

    .... ISAAC is designed to follow a specific person using solely vision based techniques. The core of the vision based algorithms used in this application is based on years of research from a collaboration of government and university partners...

  9. Autonomous Robotic Following Using Vision Based Techniques

    National Research Council Canada - National Science Library

    Kania, Robert T; Del Rose, Michael

    2005-01-01

    .... ISAAC is designed to follow a specific person using solely vision based techniques. The core of the vision based algorithms used in this application is based on years of research from a collaboration of government and university partners...

  10. Molecular evolution of bat color vision genes.

    Science.gov (United States)

    Wang, Daryi; Oakley, Todd; Mower, Jeffrey; Shimmin, Lawrence C; Yim, Sokchea; Honeycutt, Rodney L; Tsao, Hsienshao; Li, Wen-Hsiung

    2004-02-01

    The two suborders of bats, Megachiroptera (megabats) and Microchiroptera (microbats), use different sensory modalities for perceiving their environment. Megabats are crepuscular and rely on a well-developed eyes and visual pathway, whereas microbats occupy a nocturnal niche and use acoustic orientation or echolocation more than vision as the major means of perceiving their environment. In view of the differences associated with their sensory systems, we decided to investigate the function and evolution of color vision (opsin genes) in these two suborders of bats. The middle/long wavelength (M/L) and short wavelength (S) opsin genes were sequenced from two frugivorous species of megabats, Haplonycteris fischeri and Pteropus dasymallus formosus, and one insectivorous species of microbat, Myotis velifer. Contrary to the situation in primates, where many nocturnal species have lost the functional S opsin gene, both crepuscular and strictly nocturnal species of bats that we examined have functional M/L and S opsin genes. Surprisingly, the S opsin in these bats may be sensitive to UV light, which is relatively more abundant at dawn and at dusk. The M/L opsin in these bats appears to be the L type, which is sensitive to red and may be helpful for identifying fruits among leaves or for other purposes. Most interestingly, H. fischeri has a recent duplication of the M/L opsin gene, representing to date the only known case of opsin gene duplication in non-primate mammals. Some of these observations are unexpected and may provide insights into the effect of nocturnal life on the evolution of opsin genes in mammals and the evolution of the life history traits of bats in general.

  11. Neurogenic vision loss: Causes and outcome. An experience from a tertiary center in Northern India

    Directory of Open Access Journals (Sweden)

    Rajesh Verma

    2014-01-01

    Full Text Available Introduction: Vision loss can be a consequence of numerous disorders of eye and neural pathway conveying visual input to brain. A variety of conditions can affect visual pathway producing neurogenic vision loss. The presentation and course of vision loss depends on the site of involvement and underlying etiology. We conducted this unprecedented study to evaluate the characteristics and outcome of various diseases of the visual pathway. Materials and Methods: In this prospective cohort study, we evaluated 64 patients with neurogenic visual impairment. Ophthalmological causes were excluded in all of them. Their presentation, ophthalmological characteristics and investigation findings were recorded. These patients were followed up till 6 months. Results: Out of 69 patients evaluated, 5 were excluded as they had ophthalmological abnormalities. The remaining 64 cases (113 eyes were enrolled. 54 cases were due to diseases of anterior visual pathway and rest 10 had cortical vision loss. The etiologic distribution is as follows: Isolated optic neuritis- 12 (19%, multiple sclerosis- 4 (6.3%, neuromyelitis optica- 5 (7.9%, tubercular meningitis- 15 (23.8%, non-arteritic ischemic optic neuropathy, ischemic optic neuropathy complicating cavernous sinus thrombosis, cryptococcal meningitis, malignant infiltration of optic nerve, Crouzon′s syndrome, calvarial thickening and traumatic occipital gliosis- 1 (1.6% case each, idiopathic intracranial hypertension, pituitary adenoma, acute disseminated encephalomyelitis, posterior reversible leukoencephalopathy- 3 (4.8% cases each, cortical venous thrombosis 5 (7.9%, subacute scleroing panencephalitis- 4 (6.3% cases. Conclusions: The diseases of anterior visual pathway were much more common than cortical vision loss. A majority of our patients had severe impairment of vision at presentation.

  12. Cities and Climate - What Visions?

    International Nuclear Information System (INIS)

    Haentjens, Jean

    2015-01-01

    Given the difficulty of achieving a global agreement to cope with the challenges of climate change or even a national resilience programme, an increasing number of initiatives are coming up from the local level for preemptively implementing policies to adapt to climate change or combat it. There are several towns and cities across the world that have taken this line (Copenhagen, Totnes, Vaexjoe, Bristol, etc.) but, as Jean Haentjens shows here, an effective response to climate change requires the development of a genuine strategic vision capable of mobilizing all the actors concerned. For the moment, the towns and cities that have managed to come up with such a vision are few and far between. After a -largely historical- review of the importance of vision in changes of urban paradigm, Jean Haentjens stresses how much twenty-first century eco-urbanism broadens the range of possible solutions to the many issues facing our towns and cities today. But, though digital innovations in fact offer new opportunities at the local level, we should nonetheless be wary of 'technological solutionism': the new technologies are tools which towns and cities can use to their advantage, but to become really 'smart' they have to develop a vision. After presenting a series of established or emerging urban models (the frugal city, the creative city, the leisure city and the eco-metropolis), along with the values and imaginative conceptions that underpin them, this article shows - without being unaware of the potential obstacles - how a town or city can produce and renew its strategic vision to reinvent itself and meet the challenges of today

  13. Polar patterns of driven filaments.

    Science.gov (United States)

    Schaller, Volker; Weber, Christoph; Semmrich, Christine; Frey, Erwin; Bausch, Andreas R

    2010-09-02

    The emergence of collective motion exhibited by systems ranging from flocks of animals to self-propelled microorganisms to the cytoskeleton is a ubiquitous and fascinating self-organization phenomenon. Similarities between these systems, such as the inherent polarity of the constituents, a density-dependent transition to ordered phases or the existence of very large density fluctuations, suggest universal principles underlying pattern formation. This idea is followed by theoretical models at all levels of description: micro- or mesoscopic models directly map local forces and interactions using only a few, preferably simple, interaction rules, and more macroscopic approaches in the hydrodynamic limit rely on the systems' generic symmetries. All these models characteristically have a broad parameter space with a manifold of possible patterns, most of which have not yet been experimentally verified. The complexity of interactions and the limited parameter control of existing experimental systems are major obstacles to our understanding of the underlying ordering principles. Here we demonstrate the emergence of collective motion in a high-density motility assay that consists of highly concentrated actin filaments propelled by immobilized molecular motors in a planar geometry. Above a critical density, the filaments self-organize to form coherently moving structures with persistent density modulations, such as clusters, swirls and interconnected bands. These polar nematic structures are long lived and can span length scales orders of magnitudes larger than their constituents. Our experimental approach, which offers control of all relevant system parameters, complemented by agent-based simulations, allows backtracking of the assembly and disassembly pathways to the underlying local interactions. We identify weak and local alignment interactions to be essential for the observed formation of patterns and their dynamics. The presented minimal polar-pattern-forming system

  14. Polarization at the SLC

    Energy Technology Data Exchange (ETDEWEB)

    Moffeit, K.C.

    1988-10-01

    The Stanford Linear collider was designed to accommodate polarized electron beams. Longitudinally polarized electrons colliding with unpolarized positrons at a center of mass energy near the Z/sup 0/ mass can be used as novel and sensitive probes of the electroweak process. A gallium arsenide based photon emission source will provide a beam of longitudinally polarized electrons of about 45 percent polarization. A system of bend magnets and a superconducting solenoid will be used to rotate the spins so that the polarization is preserved while the 1.21 GeV electrons are stored in the damping ring. Another set of bend magnets and two superconducting solenoids orient the spin vectors so that longitudinal polarization of the electrons is achieved at the collision point with the unpolarized positrons. A system to monitor the polarization based on Moller and Compton scattering will be used. Nearly all major components have been fabricated and tested. Subsystems of the source and polarimeters have been installed, and studies are in progress. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. 8 refs., 16 figs., 1 tab.

  15. School Vision of Learning: Urban Setting

    Science.gov (United States)

    Guy, Tiffany A.

    2010-01-01

    In this paper, the author develops her school vision of learning. She explains the theories she used to help develop the vision. The author then goes into detail on the methods she will use to make her vision for a school that prepares urban students for a successful life after high school. She takes into account all the stakeholders and how they…

  16. The many roles of vision during walking

    NARCIS (Netherlands)

    Logan, David; Kiemel, Tim; Dominici, Nadia; Cappellini, Germana; Ivanenko, Yuri; Lacquaniti, Francesco; Jeka, John J

    2010-01-01

    Vision can improve bipedal upright stability during standing and locomotion. However, during locomotion, vision supports additional behaviors such as gait cycle modulation, navigation, and obstacle avoidance. Here, we investigate how the multiple roles of vision are reflected in the dynamics of

  17. Coaching Peripheral Vision Training for Soccer Athletes

    Science.gov (United States)

    Marques, Nelson Kautzner, Jr.

    2010-01-01

    Brazilian Soccer began developing its current emphasis on peripheral vision in the late 1950s, by initiative of coach of the Canto do Rio Football Club, in Niteroi, Rio de Janeiro, a pioneer in the development of peripheral vision training in soccer players. Peripheral vision training gained world relevance when a young talent from Canto do Rio,…

  18. Marr's vision: twenty-five years on.

    Science.gov (United States)

    Glennerster, Andrew

    2007-06-05

    It is twenty-five years since the posthumous publication of David Marr's book Vision[1]. Only 35 years old when he died, Marr had already dramatically influenced vision research. His book, and the series of papers that preceded it, have had a lasting impact on the way that researchers approach human and computer vision.

  19. Marr's vision: Twenty-five years on

    OpenAIRE

    Glennerster, Andrew

    2007-01-01

    It is twenty-five years since the posthumous publication of David Marr's book Vision [1]. Only 35 years old when he died, Man, had already dramatically influenced vision research. His book, and the series of papers that preceded it, have had a lasting impact on the way that researchers approach human and computer vision.

  20. Polarized atomic beams for targets

    International Nuclear Information System (INIS)

    Grueebler, W.

    1984-01-01

    The basic principle of the production of polarized atomic hydrogen and deuterium beams are reviewed. The status of the present available polarization, density and intensity are presented. The improvement of atomic beam density by cooling the hydrogen atoms to low velocity is discussed. The possible use of polarized atomic beams as targets in storage rings is shown. It is proposed that polarized atomic beams can be used to produce polarized gas targets with high polarization and greatly improved density

  1. Polarized scintillator targets

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2000-05-01

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as "live" polarized targets in nuclear physics experiments.

  2. Polarized scintillator targets

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, B. van den E-mail: vandenbrandt@psi.ch; Bunyatova, E.I.; Hautle, P.; Konter, J.A.; Mango, S

    2000-05-21

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as 'live' polarized targets in nuclear physics experiments.

  3. Heidelberg polarized alkali source

    International Nuclear Information System (INIS)

    Kraemer, D.; Steffens, E.; Jaensch, H.; Philipps Universitaet, Marburg, Germany)

    1984-01-01

    A new atomic beam type polarized alkali ion source has been installed at Heidelberg. In order to improve the beam polarization considerably optical pumping is applied in combination with an adiabatic medium field transition which results in beams in single hyperfine sublevels. The m state population is determined by laser-induced fluorescence spectroscopy. Highly polarized beams (P/sub s/ > 0.9, s = z, zz) with intensities of 30 to 130 μA can be extracted for Li + and Na + , respectively

  4. Polarization measurement in the COMPASS polarized target

    CERN Document Server

    Kondo, K; Baum, G; Berglund, P; Doshita, N; Gautheron, F; Görtz, S; Hasegawa, T; Horikawa, N; Ishimoto, S; Iwata, T; Kisselev, Yu V; Koivuniemi, J H; Le Goff, J M; Magnon, A; Meyer, W; Reicherz, G; Matsuda, T

    2004-01-01

    Continuous wave nuclear magnetic resonance (NMR) is used to determine the target polarization in the COMPASS experiment. The system is made of the so-called Liverpool Q-meters, Yale-cards, and VME modules for data taking and system controlling. In 2001 the NMR coils were embedded in the target material, while in 2002 and 2003 the coils were mounted on the outer surface of the target cells to increase the packing factor of the material. Though the error of the measurement became larger with the outer coils than with the inner coils, we have performed stable measurements throughout the COMPASS run time for 3 years. The maximum polarization was +57% and -53% as the average in the target cells.

  5. Biological Pathways

    Science.gov (United States)

    Skip to main content Biological Pathways Fact Sheet Enter Search Term(s): Español Research Funding An Overview Bioinformatics Current Grants Education and Training Funding Extramural Research News Features ...

  6. Dynamic nuclear spin polarization

    Energy Technology Data Exchange (ETDEWEB)

    Stuhrmann, H.B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    1996-11-01

    Polarized neutron scattering from dynamic polarized targets has been applied to various hydrogenous materials at different laboratories. In situ structures of macromolecular components have been determined by nuclear spin contrast variation with an unprecedented precision. The experiments of selective nuclear spin depolarisation not only opened a new dimension to structural studies but also revealed phenomena related to propagation of nuclear spin polarization and the interplay of nuclear polarisation with the electronic spin system. The observation of electron spin label dependent nuclear spin polarisation domains by NMR and polarized neutron scattering opens a way to generalize the method of nuclear spin contrast variation and most importantly it avoids precontrasting by specific deuteration. It also likely might tell us more about the mechanism of dynamic nuclear spin polarisation. (author) 4 figs., refs.

  7. Time Domain Induced Polarization

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2012-01-01

    Time-domain-induced polarization has significantly broadened its field of reference during the last decade, from mineral exploration to environmental geophysics, e.g., for clay and peat identification and landfill characterization. Though, insufficient modeling tools have hitherto limited the use...... of time-domaininduced polarization for wider purposes. For these reasons, a new forward code and inversion algorithm have been developed using the full-time decay of the induced polarization response, together with an accurate description of the transmitter waveform and of the receiver transfer function......%. Furthermore, the presence of low-pass filters in time-domain-induced polarization instruments affects the early times of the acquired decays (typically up to 100 ms) and has to be modeled in the forward response to avoid significant loss of resolution. The developed forward code has been implemented in a 1D...

  8. Polarized proton colliders

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. This will allow the study of the spin structure of the proton and also the verification of the many well documented expectations of spin effects in perturbative QCD and parity violation in W and Z production. Proposals for polarized proton acceleration for several high energy colliders have been developed. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. This allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 x 10 32 cm -2 s -1

  9. Temporary effects of alcohol on color vision

    Science.gov (United States)

    Geniusz, Maciej K.; Geniusz, Malwina; Szmigiel, Marta; Przeździecka-Dołyk, Joanna

    2017-09-01

    The color vision has been described as one to be very sensitive to the intake of several chemicals. The present research reviews the published literature that is concerned with color vision impairment due to alcohol. Most of this research considers people under long-term effects of alcohol. However, there is little information about temporary effects of alcohol on color vision. A group of ten volunteers aged 18-40 was studied. During the study levels of alcohol in the body were tested with a standard breathalyzer while color vision were studied using Farnsworth Munsell 100 Hue Color Vision Tests. Keywords: Col

  10. VISION User Guide - VISION (Verifiable Fuel Cycle Simulation) Model

    Energy Technology Data Exchange (ETDEWEB)

    Jacob J. Jacobson; Robert F. Jeffers; Gretchen E. Matthern; Steven J. Piet; Benjamin A. Baker; Joseph Grimm

    2009-08-01

    The purpose of this document is to provide a guide for using the current version of the Verifiable Fuel Cycle Simulation (VISION) model. This is a complex model with many parameters; the user is strongly encouraged to read this user guide before attempting to run the model. This model is an R&D work in progress and may contain errors and omissions. It is based upon numerous assumptions. This model is intended to assist in evaluating “what if” scenarios and in comparing fuel, reactor, and fuel processing alternatives at a systems level for U.S. nuclear power. The model is not intended as a tool for process flow and design modeling of specific facilities nor for tracking individual units of fuel or other material through the system. The model is intended to examine the interactions among the components of a fuel system as a function of time varying system parameters; this model represents a dynamic rather than steady-state approximation of the nuclear fuel system. VISION models the nuclear cycle at the system level, not individual facilities, e.g., “reactor types” not individual reactors and “separation types” not individual separation plants. Natural uranium can be enriched, which produces enriched uranium, which goes into fuel fabrication, and depleted uranium (DU), which goes into storage. Fuel is transformed (transmuted) in reactors and then goes into a storage buffer. Used fuel can be pulled from storage into either separation of disposal. If sent to separations, fuel is transformed (partitioned) into fuel products, recovered uranium, and various categories of waste. Recycled material is stored until used by its assigned reactor type. Note that recovered uranium is itself often partitioned: some RU flows with recycled transuranic elements, some flows with wastes, and the rest is designated RU. RU comes out of storage if needed to correct the U/TRU ratio in new recycled fuel. Neither RU nor DU are designated as wastes. VISION is comprised of several

  11. VISION User Guide - VISION (Verifiable Fuel Cycle Simulation) Model

    International Nuclear Information System (INIS)

    Jacobson, Jacob J.; Jeffers, Robert F.; Matthern, Gretchen E.; Piet, Steven J.; Baker, Benjamin A.; Grimm, Joseph

    2009-01-01

    The purpose of this document is to provide a guide for using the current version of the Verifiable Fuel Cycle Simulation (VISION) model. This is a complex model with many parameters; the user is strongly encouraged to read this user guide before attempting to run the model. This model is an R and D work in progress and may contain errors and omissions. It is based upon numerous assumptions. This model is intended to assist in evaluating 'what if' scenarios and in comparing fuel, reactor, and fuel processing alternatives at a systems level for U.S. nuclear power. The model is not intended as a tool for process flow and design modeling of specific facilities nor for tracking individual units of fuel or other material through the system. The model is intended to examine the interactions among the components of a fuel system as a function of time varying system parameters; this model represents a dynamic rather than steady-state approximation of the nuclear fuel system. VISION models the nuclear cycle at the system level, not individual facilities, e.g., 'reactor types' not individual reactors and 'separation types' not individual separation plants. Natural uranium can be enriched, which produces enriched uranium, which goes into fuel fabrication, and depleted uranium (DU), which goes into storage. Fuel is transformed (transmuted) in reactors and then goes into a storage buffer. Used fuel can be pulled from storage into either separation of disposal. If sent to separations, fuel is transformed (partitioned) into fuel products, recovered uranium, and various categories of waste. Recycled material is stored until used by its assigned reactor type. Note that recovered uranium is itself often partitioned: some RU flows with recycled transuranic elements, some flows with wastes, and the rest is designated RU. RU comes out of storage if needed to correct the U/TRU ratio in new recycled fuel. Neither RU nor DU are designated as wastes. VISION is comprised of several Microsoft

  12. Plasma polarization spectroscopy

    International Nuclear Information System (INIS)

    Iwamae, Atsushi; Horimoto, Yasuhiro; Fujimoto, Takashi; Hasegawa, Noboru; Sukegawa, Kouta; Kawachi, Tetsuya

    2005-01-01

    The electron velocity distribution function (EVDF) in plasma can be anisotropic in laser-produced plasmas. We have developed a new technique to evaluate the polarization degree of the emission lines in the extreme vacuum ultra violet wavelength region. The polarization of the emission lines and the continuums from the lithium-like nitrogen and from helium- and hydrogen-like carbon in recombining plasma is evaluated. Particle simulation in the velocity space gives the time scale for relaxation of anisotropic EVDFs. (author)

  13. Ultracold Polar Molecules

    Science.gov (United States)

    2016-04-01

    AFRL-AFOSR-UK-TR-2016-0005 Ultracold Polar Molecules Jeremy Hutson UNIVERSITY OF DURHAM Final Report 04/01/2016 DISTRIBUTION A: Distribution approved...DATES COVERED (From - To) 15-Jan-2010 to 14-Jul-2015 4. TITLE AND SUBTITLE Final Report on Grant FA8655-10-1-3033 on Ultracold Polar Molecules 5a...formation of ultracold 87RbCs molecules in their rovibrational ground state by magnetoassociation followed by STIRAP, resulting in 14 papers acknowledging

  14. The vision of David Marr.

    Science.gov (United States)

    Stevens, Kent A

    2012-01-01

    Marr proposed a computational paradigm for studying the visual system, wherein aspects of vision would be amenable to study with what might be regarded a computational-reductionist approach. First, vision would be cleaved into separable 'computational theories', in which the visual system is characterized in terms of its computational goals and the strategies by which they are carried out. Each such computational theory could then be investigated in increasingly concrete terms, from symbols and measurements, to representations and algorithms, to processes and neural implementations. This paradigm rests on some general expectations of a symbolic information processing system, including his stated principles of explicit naming, modular design, least commitment, and graceful degradation. In retrospect, the computational framework also tacitly rests on additional assumptions about the nature of biological information processing: (1) separability of computational strategies, (2) separability of representations, (3) a pipeline nature of information processing, and that (4) the representations employ primitives of low dimensionality. These assumptions are discussed in this retrospective.

  15. Rendering for machine vision prototyping

    Science.gov (United States)

    Reiner, Jacek

    2008-09-01

    Machine Vision systems for manufacturing quality inspection are interdisciplinary solutions including lighting, optics, cameras, image processing, segmentation, feature analysis, classification as well as integration with manufacturing process. The design and optimization of the above systems, especially image acquisition setup is mainly driven by experiment. This requires deep know-how and well equipped laboratory, which does not guarantee the optimal development process and results. This paper proposes novel usage of rendering, originating from 3D computer graphics, for machine vision prototyping and optimization. The invented technique and physically-based rendering aids selection or optimization of luminaires, tolerancing of mechanical construction and object handling, robustness predetermination or surface flaw simulation. The rendering setup utilizes mesh modeling, bump and normal mapping and light distribution sharpening with IES data files. The performed light simulation experiments for metal surfaces (face surface of bearing rollers) are validated.

  16. New development in robot vision

    CERN Document Server

    Behal, Aman; Chung, Chi-Kit

    2015-01-01

    The field of robotic vision has advanced dramatically recently with the development of new range sensors.  Tremendous progress has been made resulting in significant impact on areas such as robotic navigation, scene/environment understanding, and visual learning. This edited book provides a solid and diversified reference source for some of the most recent important advancements in the field of robotic vision. The book starts with articles that describe new techniques to understand scenes from 2D/3D data such as estimation of planar structures, recognition of multiple objects in the scene using different kinds of features as well as their spatial and semantic relationships, generation of 3D object models, approach to recognize partially occluded objects, etc. Novel techniques are introduced to improve 3D perception accuracy with other sensors such as a gyroscope, positioning accuracy with a visual servoing based alignment strategy for microassembly, and increasing object recognition reliability using related...

  17. Computer vision in microstructural analysis

    Science.gov (United States)

    Srinivasan, Malur N.; Massarweh, W.; Hough, C. L.

    1992-01-01

    The following is a laboratory experiment designed to be performed by advanced-high school and beginning-college students. It is hoped that this experiment will create an interest in and further understanding of materials science. The objective of this experiment is to demonstrate that the microstructure of engineered materials is affected by the processing conditions in manufacture, and that it is possible to characterize the microstructure using image analysis with a computer. The principle of computer vision will first be introduced followed by the description of the system developed at Texas A&M University. This in turn will be followed by the description of the experiment to obtain differences in microstructure and the characterization of the microstructure using computer vision.

  18. Basic design principles of colorimetric vision systems

    Science.gov (United States)

    Mumzhiu, Alex M.

    1998-10-01

    Color measurement is an important part of overall production quality control in textile, coating, plastics, food, paper and other industries. The color measurement instruments such as colorimeters and spectrophotometers, used for production quality control have many limitations. In many applications they cannot be used for a variety of reasons and have to be replaced with human operators. Machine vision has great potential for color measurement. The components for color machine vision systems, such as broadcast quality 3-CCD cameras, fast and inexpensive PCI frame grabbers, and sophisticated image processing software packages are available. However the machine vision industry has only started to approach the color domain. The few color machine vision systems on the market, produced by the largest machine vision manufacturers have very limited capabilities. A lack of understanding that a vision based color measurement system could fail if it ignores the basic principles of colorimetry is the main reason for the slow progress of color vision systems. the purpose of this paper is to clarify how color measurement principles have to be applied to vision systems and how the electro-optical design features of colorimeters have to be modified in order to implement them for vision systems. The subject of this presentation far exceeds the limitations of a journal paper so only the most important aspects will be discussed. An overview of the major areas of applications for colorimetric vision system will be discussed. Finally, the reasons why some customers are happy with their vision systems and some are not will be analyzed.

  19. Hsp Polarization Verification

    Science.gov (United States)

    Bless, Robert

    1991-07-01

    This proposal defines the procedure for determining the instrumental polarization of the polarimetric IDT (IDT#1, POL) on the HSP. 1 of 2 unpolarized standard stars wil be observed using various filter-polarizer combinations. These observations will permit the instrumental polarization to be calibrated. The instrumental polarization must be determined to a high precision in order to vectoriallly remove it from HSP polarization observations to determine the actual astronomical polarization. Final run of proposal will look at one of 2 possible stars previously observed to get another look at the throughput. Revision History: Mark H. Slovak 8/30/88 Translated to V2 proposal instructions (RPSS V6.2) S. Laurent 1/20/89 Updated: Sally Laurent 2/24/89, 3/20/89, 4/13/89, 5/12/89 Modified: P. Stanley 1/15/90 - change to use CTA selected targets only; Fixes for aberration problem - SALM 7/30/90; Based on SV/HSP 1386. New submission changed targets and revised scheduling strategy. Revised: 26 Aug 92 J. Dolan, L. Walter, P. Reppert want to re-run the proposal (3985) one last time to bring down errors.

  20. Understanding and preventing computer vision syndrome.

    Science.gov (United States)

    Loh, Ky; Redd, Sc

    2008-01-01

    The invention of computer and advancement in information technology has revolutionized and benefited the society but at the same time has caused symptoms related to its usage such as ocular sprain, irritation, redness, dryness, blurred vision and double vision. This cluster of symptoms is known as computer vision syndrome which is characterized by the visual symptoms which result from interaction with computer display or its environment. Three major mechanisms that lead to computer vision syndrome are extraocular mechanism, accommodative mechanism and ocular surface mechanism. The visual effects of the computer such as brightness, resolution, glare and quality all are known factors that contribute to computer vision syndrome. Prevention is the most important strategy in managing computer vision syndrome. Modification in the ergonomics of the working environment, patient education and proper eye care are crucial in managing computer vision syndrome.

  1. Dynamical Systems and Motion Vision.

    Science.gov (United States)

    1988-04-01

    TASK Artificial Inteligence Laboratory AREA I WORK UNIT NUMBERS 545 Technology Square . Cambridge, MA 02139 C\\ II. CONTROLLING OFFICE NAME ANO0 ADDRESS...INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A.I.Memo No. 1037 April, 1988 Dynamical Systems and Motion Vision Joachim Heel Abstract: In this... Artificial Intelligence L3 Laboratory of the Massachusetts Institute of Technology. Support for the Laboratory’s [1 Artificial Intelligence Research is

  2. Machine vision theory, algorithms, practicalities

    CERN Document Server

    Davies, E R

    2005-01-01

    In the last 40 years, machine vision has evolved into a mature field embracing a wide range of applications including surveillance, automated inspection, robot assembly, vehicle guidance, traffic monitoring and control, signature verification, biometric measurement, and analysis of remotely sensed images. While researchers and industry specialists continue to document their work in this area, it has become increasingly difficult for professionals and graduate students to understand the essential theory and practicalities well enough to design their own algorithms and systems. This book directl

  3. Operational Assessment of Color Vision

    Science.gov (United States)

    2016-06-20

    reported as the average of the right and left eye . The CCT result was the score of the affected cone for color deficient subjects and the average of...unlimited. STINFO COPY AFRL-SA-WP-TR-2016-0008 Operational Assessment of Color Vision Steve Wright, O.D.; James Gaska, Ph.D...drawings, specifications, or other data does not license the holder or any other person or corporation or convey any rights or permission to manufacture

  4. Learning disabilities, dyslexia, and vision.

    Science.gov (United States)

    Handler, Sheryl M; Fierson, Walter M; Section on Ophthalmology

    2011-03-01

    Learning disabilities constitute a diverse group of disorders in which children who generally possess at least average intelligence have problems processing information or generating output. Their etiologies are multifactorial and reflect genetic influences and dysfunction of brain systems. Reading disability, or dyslexia, is the most common learning disability. It is a receptive language-based learning disability that is characterized by difficulties with decoding, fluent word recognition, rapid automatic naming, and/or reading-comprehension skills. These difficulties typically result from a deficit in the phonologic component of language that makes it difficult to use the alphabetic code to decode the written word. Early recognition and referral to qualified professionals for evidence-based evaluations and treatments are necessary to achieve the best possible outcome. Because dyslexia is a language-based disorder, treatment should be directed at this etiology. Remedial programs should include specific instruction in decoding, fluency training, vocabulary, and comprehension. Most programs include daily intensive individualized instruction that explicitly teaches phonemic awareness and the application of phonics. Vision problems can interfere with the process of reading, but children with dyslexia or related learning disabilities have the same visual function and ocular health as children without such conditions. Currently, there is inadequate scientific evidence to support the view that subtle eye or visual problems cause or increase the severity of learning disabilities. Because they are difficult for the public to understand and for educators to treat, learning disabilities have spawned a wide variety of scientifically unsupported vision-based diagnostic and treatment procedures. Scientific evidence does not support the claims that visual training, muscle exercises, ocular pursuit-and-tracking exercises, behavioral/perceptual vision therapy, "training" glasses

  5. A vision for photovoltaic technology

    Energy Technology Data Exchange (ETDEWEB)

    Sinke, W.C. [ECN Solar Energy, Petten (Netherlands); Perezagua, E. [Isofoton, Madrid (Spain); Demarcq, F.; Bal, J.L. [ADEME, Paris (France); Alferov, Z.I.; Andreev, V. [Ioffe Physico-Technical Institute, St. Petersburg (Russian Federation); De Segundo, K. [Shell International Renewables, London (United Kingdom); Dimmler, B. [Wuerth Solar GMBH und Co.KG, Marbach am Neckar (Germany); Goetzberger, A. [Fraunhofer Institute for Solar Energy Systems, Freiburg (Germany); Itoiz Beunza, C. [Energia Hidroelectrica de Navarra, Pamplona (Spain); Lojkowski, W. [High Pressure Research Center, Polish Academy of Sciences, Warszawa (Poland); Nowak, S. [NET Nowak nergy and Technology Ltd, St. Ursen (Switzerland); Vleuten, P. van der [Free Energy International, Eindhoven (Netherlands); Van Zolingen, R.J.C. [Shell Solar, Amsterdam (Netherlands)

    2005-02-01

    The report identifies the major technical and non-technical barriers to the uptake of the technology and outlines a strategic research agenda designed to ensure a breakthrough of PV (photovoltaics) and an increase in deployment in the Union and worldwide. The Council proposes the use of a European Technology Platform as a mechanism to implement the strategy and achieve the wider goals defined in the vision.

  6. Nuclear Fusion with Polarized Nucleons & PolFusion

    CERN Document Server

    Engels, Ralf; Büscher, Markus; Vasilyev, Alexander

    2016-01-01

    This book offers a detailed examination of the latest work on the potential of polarized fuel to realize the vision of energy production by nuclear fusion. It brings together contributions from nuclear physicists and fusion physicists with the aims of fostering exchange of information between the two communities, describing the current status in the field, and examining new ideas and projects under development. It is evident that polarized fuel can offer huge improvements for the first generation of fusion reactors and open new technological possibilities for future generations, including neutron lean reactors, which could be the most popular and sustainable energy production option to avoid environmental problems. Nevertheless, many questions must be resolved before polarized fuel can be used for energy production in the different reactor types. Readers will find this book to be a stimulating source of information on the key issues. It is based on contributions from leading scientists delivered at the meetin...

  7. Steroid hormone profile in female polar bears (Ursus maritimus)

    DEFF Research Database (Denmark)

    Gustavson, Lisa; Jenssen, Bjorn Munro; Bytingsvik, Jenny

    2015-01-01

    -4 pathway in polar bears, similar to rodents. The large individual variability in steroid levels reported here most likely reflects the differences in reproductive status of the female polar bears during mating season. The steroid data establish reference values of steroid hormones and may...... is the first study to report circulating concentrations of nine steroid hormones (i.e., estrogens, androgens and progestagens) in female polar bears (Ursus maritimus). The aim of the study was to investigate the effects of age, condition, location and reproductive status on steroid profile in female polar...... bears. Levels of pregnenolone (PRE), progesterone, androstenedione (AN), dehydroepiandrosterone (DHEA), testosterone, dihydrotestosterone, estrone (E1), 17α-estradiol (αE2) and 17β-estradiol (βE2) were quantified in blood (serum) of free-living female polar bears (n = 15) from Svalbard, Norway, by gas...

  8. A Vision and Strategy:Predictive Ecotoxicology in the 21st Century

    Science.gov (United States)

    The manuscript provides an introduction and overview for a series of five papers resulting from a SETAC Pellston Workshop titled A Vision and Strategy for Predictive Ecotoxicology in the 21st Century: Defining Adverse Outcome Pathways Associated with Ecological Risk. It proposes...

  9. Riemannian computing in computer vision

    CERN Document Server

    Srivastava, Anuj

    2016-01-01

    This book presents a comprehensive treatise on Riemannian geometric computations and related statistical inferences in several computer vision problems. This edited volume includes chapter contributions from leading figures in the field of computer vision who are applying Riemannian geometric approaches in problems such as face recognition, activity recognition, object detection, biomedical image analysis, and structure-from-motion. Some of the mathematical entities that necessitate a geometric analysis include rotation matrices (e.g. in modeling camera motion), stick figures (e.g. for activity recognition), subspace comparisons (e.g. in face recognition), symmetric positive-definite matrices (e.g. in diffusion tensor imaging), and function-spaces (e.g. in studying shapes of closed contours).   ·         Illustrates Riemannian computing theory on applications in computer vision, machine learning, and robotics ·         Emphasis on algorithmic advances that will allow re-application in other...

  10. Computer vision in control systems

    CERN Document Server

    Jain, Lakhmi

    2015-01-01

    Volume 1 : This book is focused on the recent advances in computer vision methodologies and technical solutions using conventional and intelligent paradigms. The Contributions include: ·         Morphological Image Analysis for Computer Vision Applications. ·         Methods for Detecting of Structural Changes in Computer Vision Systems. ·         Hierarchical Adaptive KL-based Transform: Algorithms and Applications. ·         Automatic Estimation for Parameters of Image Projective Transforms Based on Object-invariant Cores. ·         A Way of Energy Analysis for Image and Video Sequence Processing. ·         Optimal Measurement of Visual Motion Across Spatial and Temporal Scales. ·         Scene Analysis Using Morphological Mathematics and Fuzzy Logic. ·         Digital Video Stabilization in Static and Dynamic Scenes. ·         Implementation of Hadamard Matrices for Image Processing. ·         A Generalized Criterion ...

  11. Artificial vision: principles and prospects.

    Science.gov (United States)

    Gilhooley, Michael J; Acheson, James

    2017-02-01

    The aim of this article is to give an overview of the strategies and technologies currently under development to return vision to blind patients and will answer the question: What options exist for artificial vision in patients blind from retinal disease; how close are these to clinical practice? Retinal approaches will be the focus of this review as they are most advanced in terms not only of development, but entry into the imagination of the general public; they are technologies patients ask about, but may be less familiar to practicing neurologists.The prerequisites for retinal survivor cell stimulation are discussed, followed by consideration of the state of the art of four promising methods making use of this principle: electronic prostheses, stem cells, gene therapy and the developing field of ophthalmic optogenetics. Human applications of artificial vision by survivor cell stimulation are certainly with us in the research clinic and very close to commercialization and general use. This, together with their place in the public consciousness, makes the overview provided by this review particularly helpful to practicing neurologists.

  12. Information architecture. Volume 4: Vision

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The Vision document marks the transition from definition to implementation of the Department of Energy (DOE) Information Architecture Program. A description of the possibilities for the future, supported by actual experience with a process model and tool set, points toward implementation options. The directions for future information technology investments are discussed. Practical examples of how technology answers the business and information needs of the organization through coordinated and meshed data, applications, and technology architectures are related. This document is the fourth and final volume in the planned series for defining and exhibiting the DOE information architecture. The targeted scope of this document includes DOE Program Offices, field sites, contractor-operated facilities, and laboratories. This document paints a picture of how, over the next 7 years, technology may be implemented, dramatically improving the ways business is conducted at DOE. While technology is mentioned throughout this document, the vision is not about technology. The vision concerns the transition afforded by technology and the process steps to be completed to ensure alignment with business needs. This goal can be met if those directing the changing business and mission-support processes understand the capabilities afforded by architectural processes.

  13. Quantum vision in three dimensions

    Directory of Open Access Journals (Sweden)

    Yehuda Roth

    Full Text Available We present four models for describing a 3-D vision. Similar to the mirror scenario, our models allow 3-D vision with no need for additional accessories such as stereoscopic glasses or a hologram film. These four models are based on brain interpretation rather than pure objective encryption.We consider the observer “subjective” selection of a measuring device and the corresponding quantum collapse into one of his selected states, as a tool for interpreting reality in according to the observer concepts. This is the basic concept of our study and it is introduced in the first model. Other models suggests “soften” versions that might be much easier to implement. Our quantum interpretation approach contribute to the following fields. In technology the proposed models can be implemented into real devices, allowing 3-D vision without additional accessories. Artificial intelligence: In the desire to create a machine that exchange information by using human terminologies, our interpretation approach seems to be appropriate. Keyword: Pure State Mode, Combined Pure, Mixed Density Matrices, Stereoscopic Approximation, Sectors, I.C.O-model

  14. Polarized Light Microscopy

    Science.gov (United States)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  15. Computational Vision Based on Neurobiology

    Science.gov (United States)

    1993-07-09

    comprised of 5 micro-panterns per row. The stimulus was presented with an SOA of 60ms. The continuous line shows direction disrimination when the micro...these pathways is debated 19. The including dancing, running walking, identity, gender and ventral pathway passes through the areas VI, V2, V4. even sign

  16. Visible spectral imager for occultation and nightglow (VISION) for the PICASSO Mission

    Science.gov (United States)

    Saari, Heikki; Näsilä, Antti; Holmlund, Christer; Mannila, Rami; Näkki, Ismo; Ojanen, Harri J.; Fussen, Didier; Pieroux, Didier; Demoulin, Philippe; Dekemper, Emmanuel; Vanhellemont, Filip

    2015-10-01

    PICASSO - A PICo-satellite for Atmospheric and Space Science Observations is an ESA project led by the Belgian Institute for Space Aeronomy, in collaboration with VTT, Clyde Space Ltd. (UK), and the Centre Spatial de Liège (BE). VTT Technical Research Centre of Finland Ltd. will deliver the Visible Spectral Imager for Occultation and Nightglow (VISION) for the PICASSO mission. The VISION targets primarily the observation of the Earth's atmospheric limb during orbital Sun occultation. By assessing the radiation absorption in the Chappuis band for different tangent altitudes, the vertical profile of the ozone is retrieved. A secondary objective is to measure the deformation of the solar disk so that stratospheric and mesospheric temperature profiles are retrieved by inversion of the refractive raytracing problem. Finally, occasional full spectral observations of polar auroras are also foreseen. The VISION design realized with commercial of the shelf (CoTS) parts is described. The VISION instrument is small, lightweight (~500 g), Piezo-actuated Fabry-Perot Interferometer (PFPI) tunable spectral imager operating in the visible and near-infrared (430 - 800 nm). The spectral resolution over the whole wavelength range will be better than 10 nm @ FWHM. VISION has is 2.5° x 2.5° total field of view and it delivers maximum 2048 x 2048 pixel spectral images. The sun image size is around 0.5° i.e. ~500 pixels. To enable fast spectral data image acquisition VISION can be operated with programmable image sizes. VTT has previously developed PFPI tunable filter based AaSI Spectral Imager for the Aalto-1 Finnish CubeSat. In VISION the requirements of the spectral resolution and stability are tighter than in AaSI. Therefore the optimization of the of the PFPI gap control loop for the operating temperature range and vacuum conditions has to be improved. VISION optical, mechanical and electrical design is described.

  17. AN INVESTIGATION OF VISION PROBLEMS AND THE VISION CARE SYSTEM IN RURAL CHINA.

    Science.gov (United States)

    Bai, Yunli; Yi, Hongmei; Zhang, Linxiu; Shi, Yaojiang; Ma, Xiaochen; Congdon, Nathan; Zhou, Zhongqiang; Boswell, Matthew; Rozelle, Scott

    2014-11-01

    This paper examines the prevalence of vision problems and the accessibility to and quality of vision care in rural China. We obtained data from 4 sources: 1) the National Rural Vision Care Survey; 2) the Private Optometrists Survey; 3) the County Hospital Eye Care Survey; and 4) the Rural School Vision Care Survey. The data from each of the surveys were collected by the authors during 2012. Thirty-three percent of the rural population surveyed self-reported vision problems. Twenty-two percent of subjects surveyed had ever had a vision exam. Among those who self-reported having vision problems, 34% did not wear eyeglasses. Fifty-four percent of those with vision problems who had eyeglasses did not have a vision exam prior to receiving glasses. However, having a vision exam did not always guarantee access to quality vision care. Four channels of vision care service were assessed. The school vision examination program did not increase the usage rate of eyeglasses. Each county-hospital was staffed with three eye-doctors having one year of education beyond high school, serving more than 400,000 residents. Private optometrists often had low levels of education and professional certification. In conclusion, our findings shows that the vision care system in rural China is inadequate and ineffective in meeting the needs of the rural population sampled.

  18. The evolution of tensor polarization

    International Nuclear Information System (INIS)

    Huang, H.; Lee, S.Y.; Ratner, L.

    1993-01-01

    By using the equation of motion for the vector polarization, the spin transfer matrix for spin tensor polarization, the spin transfer matrix for spin tensor polarization is derived. The evolution equation for the tensor polarization is studied in the presence of an isolate spin resonance and in the presence of a spin rotor, or snake

  19. Th1/Th2 paradigm extended: Macrophage polarization as an unappreciated pathogen-driven escape mechanism?

    Directory of Open Access Journals (Sweden)

    Eric eMuraille

    2014-11-01

    Full Text Available The classical view of the Th1/Th2 paradigm posits that the pathogen nature, infectious cycle and persistence represent key parameters controlling the choice of effector mechanisms operating during an immune response. Thus, efficient Th1 responses are triggered by replicating intracellular pathogens, while Th2 responses would control helminth infection and promote tissue repair during the resolution phase of an infectious event. However, this vision does not account for a growing body of data describing how pathogens exploit the polarization of the host immune response to their own benefit. Recently, the study of macrophages has illustrated a novel aspect of this arm race between pathogens and the immune system, and the central role of macrophages in homeostasis, repair and defense of all tissues is now fully appreciated. Like T lymphocytes, macrophages differentiate into distinct effectors including classically (M1 and alternatively (M2 activated macrophages. Interestingly in addition to represent immune effectors, M1/M2 cells have been shown to represent potential reservoir cells to a wide range of intracellular pathogens. Subversion of macrophage cell metabolism by microbes appears as a recently uncovered immune escape strategy. Upon infection, several microbial agents have been shown to activate host metabolic pathways leading to the production of nutrients necessary to their long term persistence in host. The purpose of this review is to summarize and discuss the strategies employed by pathogens to manipulate macrophage differentiation, and in particular their basic cell metabolism, to favor their own growth while avoiding immune control.

  20. PRISM (Polarized Radiation Imaging and Spectroscopy Mission): an extended white paper

    NARCIS (Netherlands)

    André, Philippe; Baccigalupi, Carlo; Banday, Anthony; Barbosa, Domingos; Barreiro, Belen; Bartlett, James; Bartolo, Nicola; Battistelli, Elia; Battye, Richard; Bendo, George; Benoît, Alain; Bernard, Jean-Philippe; Bersanelli, Marco; Béthermin, Matthieu; Bielewicz, Pawel; Bonaldi, Anna; Bouchet, François; Boulanger, François; Brand, Jan; Bucher, Martin; Burigana, Carlo; Cai, Zhen-Yi; Camus, Philippe; Casas, Francisco; Casasola, Viviana; Castex, Guillaume; Challinor, Anthony; Chluba, Jens; Chon, Gayoung; Colafrancesco, Sergio; Comis, Barbara; Cuttaia, Francesco; D'Alessandro, Giuseppe; Da Silva, Antonio; Davis, Richard; de Avillez, Miguel; de Bernardis, Paolo; de Petris, Marco; de Rosa, Adriano; de Zotti, Gianfranco; Delabrouille, Jacques; Désert, François-Xavier; Dickinson, Clive; Diego, Jose Maria; Dunkley, Joanna; Enßlin, Torsten; Errard, Josquin; Falgarone, Edith; Ferreira, Pedro; Ferrière, Katia; Finelli, Fabio; Fletcher, Andrew; Fosalba, Pablo; Fuller, Gary; Galli, Silvia; Ganga, Ken; García-Bellido, Juan; Ghribi, Adnan; Giard, Martin; Giraud-Héraud, Yannick; Gonzalez-Nuevo, Joaquin; Grainge, Keith; Gruppuso, Alessandro; Hall, Alex; Hamilton, Jean-Christophe; Haverkorn, Marijke; Hernandez-Monteagudo, Carlos; Herranz, Diego; Jackson, Mark; Jaffe, Andrew; Khatri, Rishi; Kunz, Martin; Lamagna, Luca; Lattanzi, Massimiliano; Leahy, Paddy; Lesgourgues, Julien; Liguori, Michele; Liuzzo, Elisabetta; Lopez-Caniego, Marcos; Macias-Perez, Juan; Maffei, Bruno; Maino, Davide; Mangilli, Anna; Martinez-Gonzalez, Enrique; Martins, Carlos J. A. P.; Masi, Silvia; Massardi, Marcella; Matarrese, Sabino; Melchiorri, Alessandro; Melin, Jean-Baptiste; Mennella, Aniello; Mignano, Arturo; Miville-Deschênes, Marc-Antoine; Monfardini, Alessandro; Murphy, Anthony; Naselsky, Pavel; Nati, Federico; Natoli, Paolo; Negrello, Mattia; Noviello, Fabio; O'Sullivan, Créidhe; Paci, Francesco; Pagano, Luca; Paladino, Rosita; Palanque-Delabrouille, Nathalie; Paoletti, Daniela; Peiris, Hiranya; Perrotta, Francesca; Piacentini, Francesco; Piat, Michel; Piccirillo, Lucio; Pisano, Giampaolo; Polenta, Gianluca; Pollo, Agnieszka; Ponthieu, Nicolas; Remazeilles, Mathieu; Ricciardi, Sara; Roman, Matthieu; Rosset, Cyrille; Rubino-Martin, Jose-Alberto; Salatino, Maria; Schillaci, Alessandro; Shellard, Paul; Silk, Joseph; Starobinsky, Alexei; Stompor, Radek; Sunyaev, Rashid; Tartari, Andrea; Terenzi, Luca; Toffolatti, Luigi; Tomasi, Maurizio; Trappe, Neil; Tristram, Matthieu; Trombetti, Tiziana; Tucci, Marco; Van de Weijgaert, Rien; Van Tent, Bartjan; Verde, Licia; Vielva, Patricio; Wandelt, Ben; Watson, Robert; Withington, Stafford

    2014-01-01

    PRISM (Polarized Radiation Imaging and Spectroscopy Mission) was proposed to ESA in May 2013 as a large-class mission for investigating within the framework of the ESA Cosmic Vision program a set of important scientific questions that require high resolution, high sensitivity, full-sky observations

  1. Artificial vision support system (AVS(2)) for improved prosthetic vision.

    Science.gov (United States)

    Fink, Wolfgang; Tarbell, Mark A

    2014-11-01

    State-of-the-art and upcoming camera-driven, implanted artificial vision systems provide only tens to hundreds of electrodes, affording only limited visual perception for blind subjects. Therefore, real time image processing is crucial to enhance and optimize this limited perception. Since tens or hundreds of pixels/electrodes allow only for a very crude approximation of the typically megapixel optical resolution of the external camera image feed, the preservation and enhancement of contrast differences and transitions, such as edges, are especially important compared to picture details such as object texture. An Artificial Vision Support System (AVS(2)) is devised that displays the captured video stream in a pixelation conforming to the dimension of the epi-retinal implant electrode array. AVS(2), using efficient image processing modules, modifies the captured video stream in real time, enhancing 'present but hidden' objects to overcome inadequacies or extremes in the camera imagery. As a result, visual prosthesis carriers may now be able to discern such objects in their 'field-of-view', thus enabling mobility in environments that would otherwise be too hazardous to navigate. The image processing modules can be engaged repeatedly in a user-defined order, which is a unique capability. AVS(2) is directly applicable to any artificial vision system that is based on an imaging modality (video, infrared, sound, ultrasound, microwave, radar, etc.) as the first step in the stimulation/processing cascade, such as: retinal implants (i.e. epi-retinal, sub-retinal, suprachoroidal), optic nerve implants, cortical implants, electric tongue stimulators, or tactile stimulators.

  2. Polarized Electrons at Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, C.K.

    1997-12-31

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously.initial operational experience with the polarized source will be presented.

  3. Polarized electrons at Jefferson laboratory

    International Nuclear Information System (INIS)

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously. Initial operational experience with the polarized source will be presented

  4. Vision Integrating Strategies in Ophthalmology and Neurochemistry (VISION)

    Science.gov (United States)

    2016-08-01

    Figure 3 in Liu et al IOVS 2014) and functional changes to the retina by electroretinography ( ERG )) (Figures 6-7 in Kim et al. Mol Neurodegen 2013...7), decreased retinal function ( ERG b- waves) (Figure 9), and neuronal loss in the superior colliculus (vision center in the brain innervated by RGC...functionally ( ERG ) (Figure 7) in mice deficient in C1q (C1q+/- and C1q-/- mice) (Silverman et al., Mol Neurodegen 2016). C1q deficiency also suppressed

  5. Beauty and cuteness in peripheral vision

    Science.gov (United States)

    Kuraguchi, Kana; Ashida, Hiroshi

    2015-01-01

    Guo et al. (2011) showed that attractiveness was detectable in peripheral vision. Since there are different types of attractiveness (Rhodes, 2006), we investigated how beauty and cuteness are detected in peripheral vision with a brief presentation. Participants (n = 45) observed two Japanese female faces for 100 ms, then were asked to respond which face was more beautiful (or cuter). The results indicated that both beauty and cuteness were detectable in peripheral vision, but not in the same manner. Discrimination rates for judging beauty were invariant in peripheral and central vision, while discrimination rates for judging cuteness declined in peripheral vision as compared with central vision. This was not explained by lower resolution in peripheral vision. In addition, for male participants, it was more difficult to judge cuteness than beauty in peripheral vision, thus suggesting that gender differences can have a certain effect when judging cuteness. Therefore, central vision might be suitable for judging cuteness while judging beauty might not be affected by either central or peripheral vision. This might be related with the functional difference between beauty and cuteness. PMID:25999883

  6. Beauty and Cuteness in Peripheral Vision

    Directory of Open Access Journals (Sweden)

    Kana eKuraguchi

    2015-05-01

    Full Text Available Guo, Liu, & Roebuck (2011 showed that attractiveness was detectable in peripheral vision. Since there are different types of attractiveness (Rhodes, 2006, we investigated how beauty and cuteness are detected in peripheral vision with a brief presentation. Participants (n = 45 observed two Japanese female faces for 100 ms, then were asked to respond which face was more beautiful (or cuter. The results indicated that both beauty and cuteness were detectable in peripheral vision, but not in the same manner. Discrimination rates for judging beauty were invariant in peripheral and central vision, while discrimination rates for judging cuteness declined in peripheral vision as compared with central vision. This was not explained by lower resolution in peripheral vision. In addition, for male participants, it was more difficult to judge cuteness than beauty in peripheral vision, thus suggesting that gender differences can have a certain effect when judging cuteness. Therefore, central vision might be suitable for judging cuteness while judging beauty might not be affected by either central or peripheral vision. This might be related with the functional difference between beauty and cuteness.

  7. Polar low monitoring

    Science.gov (United States)

    Bobylev, Leonid; Zabolotskikh, Elizaveta; Mitnik, Leonid

    2010-05-01

    Polar lows are intense mesoscale atmospheric low pressure weather systems, developing poleward of the main baroclinic zone and associated with high surface wind speeds. Small size and short lifetime, sparse in-situ observations in the regions of their development complicate polar low study. Our knowledge of polar lows and mesocyclones has come almost entirely during the period of satellite remote sensing since, by virtue of their small horizontal scale, it was rarely possible to analyse these lows on conventional weather charts using only the data from the synoptic observing network. However, the effects of intense polar lows have been felt by coastal communities and seafarers since the earliest times. These weather systems are thought to be responsible for the loss of many small vessels over the centuries, although the nature of the storms was not understood and their arrival could not be predicted. The actuality of the polar low research is stipulated by their high destructive power: they are a threat to such businesses as oil and gas exploration, fisheries and shipping. They could worsen because of global warming: a shrinking of sea ice around the North Pole, which thawed to its record minimum in the summer of 2007, is likely to give rise to more powerful storms that form only over open water and can cause hurricane-strength winds. Therefore, study of polar lows, their timely detection, tracking and forecasting represents a challenge for today meteorology. Satellite passive microwave data, starting from Special Sensor Microwave Imager (SSM/I) onboard Defense Meteorological Satellite Program (DMSP) satellite, remain invaluable source of regularly available remotely sensed data to study polar lows. The sounding in this spectral range has several advantages in comparison with observations in visible and infrared ranges and Synthetic Aperture Radar (SAR) data: independence on day time and clouds, regularity and high temporal resolution in Polar Regions. Satellite

  8. Polarized protons at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1990-12-01

    The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

  9. The Bochum Polarized Target

    International Nuclear Information System (INIS)

    Reicherz, G.; Goertz, S.; Harmsen, J.; Heckmann, J.; Meier, A.; Meyer, W.; Radtke, E.

    2001-01-01

    The Bochum 'Polarized Target' group develops the target material 6 LiD for the COMPASS experiment at CERN. Several different materials like alcohols, alcanes and ammonia are under investigation. Solid State Targets are polarized in magnetic fields higher than B=2.5T and at temperatures below T=1K. For the Dynamic Nuclear Polarization process, paramagnetic centers are induced chemically or by irradiation with ionizing beams. The radical density is a critical factor for optimization of polarization and relaxation times at adequate magnetic fields and temperatures. In a high sensitive EPR--apparatus, an evaporator and a dilution cryostat with a continuous wave NMR--system, the materials are investigated and optimized. To improve the polarization measurement, the Liverpool NMR-box is modified by exchanging the fixed capacitor for a varicap diode which not only makes the tuning very easy but also provides a continuously tuned circuit. The dependence of the signal area upon the circuit current is measured and it is shown that it follows a linear function

  10. In-line Fiber Polarizer

    OpenAIRE

    Perumalsamy, Priya

    1998-01-01

    Polarizers and polarization devices are important components in fiber optic communication and sensor systems. There is a growing need for efficient low loss components that are compatible with optical fibers. An all fiber in-line polarizer is a more desirable alternative that could be placed at appropriate intervals along communication links. An in-line fiber polarizer was fabricated and tested. The in-line fiber polarizer operates by coupling optical energy propagatin...

  11. Molecular pathways

    DEFF Research Database (Denmark)

    Cox, Thomas R; Erler, Janine Terra

    2014-01-01

    that 45% of deaths in the developed world are linked to fibrotic disease. Fibrosis and cancer are known to be inextricably linked; however, we are only just beginning to understand the common and overlapping molecular pathways between the two. Here, we discuss what is known about the intersection...... of fibrosis and cancer, with a focus on cancer metastasis, and highlight some of the exciting new potential clinical targets that are emerging from analysis of the molecular pathways associated with these two devastating diseases. Clin Cancer Res; 20(14); 3637-43. ©2014 AACR....

  12. Political Competition and Polarization

    DEFF Research Database (Denmark)

    Schultz, Christian

    This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signa...... for costs before an upcoming election. It is shown that the more polarized the political parties the more distorted the incumbent's policy choice.......This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signal...

  13. Physics of polarized targets

    CERN Document Server

    Niinikoski, Tapio

    2014-01-01

    For developing, building and operating solid polarized targets we need to understand several fields of physics that have seen sub stantial advances during the last 50 years. W e shall briefly review a selection of those that are important today. These are: 1) quantum statistical methods to describe saturation and relaxation in magnetic resonance; 2) equal spin temperature model for dy namic nuclear polarization; 3 ) weak saturation during NMR polarization measurement; 4 ) refrigeration using the quantum fluid properties of helium isotopes. These, combined with superconducting magnet technologies, permit today to reach nearly complete pola rization of almost any nuclear spins. Targets can be operated in frozen spin mode in rather low and inhomogeneous field of any orientation, and in DNP mode in beams of high intensity. Beyond such experiments of nuclear and particle physics, applications a re also emerging in macromolecular chemistry and in magnetic resonance imaging. This talk is a tribute to Michel Borghini...

  14. No More Polarization, Please!

    DEFF Research Database (Denmark)

    Hansen, Mia Reinholt

    The organizational science literature on motivation has for long been polarized into two main positions; the organizational economic position focusing on extrinsic motivation and the organizational behavior position emphasizing intrinsic motivation. With the rise of the knowledge economy...... and the increasing levels of complexities it entails, such polarization is not fruitful in the attempt to explain motivation of organizational members. This paper claims that a more nuanced perspective on motivation, acknowledging the co-existence of intrinsic and extrinsic motivation, the possible interaction...... between the two as well as different types of motivations filling in the gap between the two polar types, is urgently needed in the organizational science literature. By drawing on the research on intrinsic and extrinsic motivation conducted in social psychology and combining this with contributions from...

  15. Polarized source upgrading

    International Nuclear Information System (INIS)

    Clegg, T.B.; Rummel, R.L.; Carter, E.P.; Westerfeldt, C.R.; Lovette, A.W.; Edwards, S.E.

    1985-01-01

    The decision was made this past year to move the Lamb-shift polarized ion source which was first installed in the laboratory in 1970. The motivation was the need to improve the flexibility of spin-axis orientation by installing the ion source with a new Wien-filter spin precessor which is capable of rotating physically about the beam axis. The move of the polarized source was accomplished in approximately two months, with the accelerator being turned off for experiments during approximately four weeks of this time. The occasion of the move provided the opportunity to rewire completely the entire polarized ion source frame and to rebuild approximately half of the electronic chassis on the source. The result is an ion source which is now logically wired and carefully documented. Beams obtained from the source are much more stable than those previously available

  16. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-09-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  17. Cooperative and asynchronous stereo vision for dynamic vision sensors

    Science.gov (United States)

    Piatkowska, E.; Belbachir, A. N.; Gelautz, M.

    2014-05-01

    Dynamic vision sensors (DVSs) encode visual input as a stream of events generated upon relative light intensity changes in the scene. These sensors have the advantage of allowing simultaneously high temporal resolution (better than 10 µs) and wide dynamic range (>120 dB) at sparse data representation, which is not possible with clocked vision sensors. In this paper, we focus on the task of stereo reconstruction. The spatiotemporal and asynchronous aspects of data provided by the sensor impose a different stereo reconstruction approach from the one applied for synchronous frame-based cameras. We propose to model the event-driven stereo matching by a cooperative network (Marr and Poggio 1976 Science 194 283-7). The history of the recent activity in the scene is stored in the network, which serves as spatiotemporal context used in disparity calculation for each incoming event. The network constantly evolves in time, as events are generated. In our work, not only the spatiotemporal aspect of the data is preserved but also the matching is performed asynchronously. The results of the experiments prove that the proposed approach is well adapted for DVS data and can be successfully used for disparity calculation.

  18. POLARIZED NEUTRONS IN RHIC

    Energy Technology Data Exchange (ETDEWEB)

    COURANT,E.D.

    1998-04-27

    There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. To accelerate polarized particles in a ring, one must make provisions for overcoming the depolarizing resonances that occur at certain energies. These resonances arise when the spin tune (ratio of spin precession frequency to orbit frequency) resonates with a component present in the horizontal field. The horizontal field oscillates with the vertical motion of the particles (due to vertical focusing); its frequency spectrum is dominated by the vertical oscillation frequency and its modulation by the periodic structure of the accelerator ring. In addition, the magnet imperfections that distort the closed orbit vertically contain all integral Fourier harmonics of the orbit frequency.

  19. Women and the vision thing.

    Science.gov (United States)

    Ibarra, Herminia; Obodaru, Otilia

    2009-01-01

    Are women rated lower than men in evaluations of their leadership capabilities because of lingering gender bias? No, according to an analysis of thousands of 360-degree assessments collected by Insead's executive education program. That analysis showed that women tend to outshine men in all areas but one: vision. Unfortunately, that exception is a big one. At the top tiers of management, the ability to see opportunities, craft strategy based on a broad view of the business, and inspire others is a must-have. To explore the nature of the deficit, and whether it is a perception or reality, Insead professor Ibarra and doctoral candidate Obodaru interviewed female executives and studied the evaluation data. They developed three possible explanations. First, women may do just as much as men to shape the future but go about it in a different way; a leader who is less directive, includes more people, and shares credit might not fit people's mental model of a visionary. Second, women may believe they have less license to go out on a limb. Those who have built careers on detail-focused, shoulder-to-the-wheel execution may hesitate to stray from facts into unprovable assertions about the future. Third, women may choose not to cultivate reputations as big visionaries. Having seen bluster passed off as vision, they may dismiss the importance of selling visions. The top two candidates for the Democratic nomination for U.S. president in 2008 offer an instructive parallel. The runner-up, Hillary Clinton, was viewed as a get-it-done type with an impressive, if uninspiring, grasp of policy detail. The winner, Barack Obama, was seen as a charismatic visionary offering a hopeful, if undetailed, future. The good news is that every dimension of leadership is learned, not inborn. As more women become skilled at, and known for, envisioning the future, nothing will hold them back.

  20. Standards for vision science libraries: 2014 revision.

    Science.gov (United States)

    Motte, Kristin; Caldwell, C Brooke; Lamson, Karen S; Ferimer, Suzanne; Nims, J Chris

    2014-10-01

    This Association of Vision Science Librarians revision of the "Standards for Vision Science Libraries" aspires to provide benchmarks to address the needs for the services and resources of modern vision science libraries (academic, medical or hospital, pharmaceutical, and so on), which share a core mission, are varied by type, and are located throughout the world. Through multiple meeting discussions, member surveys, and a collaborative revision process, the standards have been updated for the first time in over a decade. While the range of types of libraries supporting vision science services, education, and research is wide, all libraries, regardless of type, share core attributes, which the standards address. The current standards can and should be used to help develop new vision science libraries or to expand the growth of existing libraries, as well as to support vision science librarians in their work to better provide services and resources to their respective users.

  1. Standards for vision science libraries: 2014 revision

    Science.gov (United States)

    Motte, Kristin; Caldwell, C. Brooke; Lamson, Karen S.; Ferimer, Suzanne; Nims, J. Chris

    2014-01-01

    Objective: This Association of Vision Science Librarians revision of the “Standards for Vision Science Libraries” aspires to provide benchmarks to address the needs for the services and resources of modern vision science libraries (academic, medical or hospital, pharmaceutical, and so on), which share a core mission, are varied by type, and are located throughout the world. Methods: Through multiple meeting discussions, member surveys, and a collaborative revision process, the standards have been updated for the first time in over a decade. Results: While the range of types of libraries supporting vision science services, education, and research is wide, all libraries, regardless of type, share core attributes, which the standards address. Conclusions: The current standards can and should be used to help develop new vision science libraries or to expand the growth of existing libraries, as well as to support vision science librarians in their work to better provide services and resources to their respective users. PMID:25349547

  2. Computer and machine vision theory, algorithms, practicalities

    CERN Document Server

    Davies, E R

    2012-01-01

    Computer and Machine Vision: Theory, Algorithms, Practicalities (previously entitled Machine Vision) clearly and systematically presents the basic methodology of computer and machine vision, covering the essential elements of the theory while emphasizing algorithmic and practical design constraints. This fully revised fourth edition has brought in more of the concepts and applications of computer vision, making it a very comprehensive and up-to-date tutorial text suitable for graduate students, researchers and R&D engineers working in this vibrant subject. Key features include: Practical examples and case studies give the 'ins and outs' of developing real-world vision systems, giving engineers the realities of implementing the principles in practice New chapters containing case studies on surveillance and driver assistance systems give practical methods on these cutting-edge applications in computer vision Necessary mathematics and essential theory are made approachable by careful explanations and well-il...

  3. Dark Polar Dunes

    Science.gov (United States)

    2005-01-01

    20 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired during northern summer in December 2004, shows dark, windblown sand dunes in the north polar region of Mars. A vast sea of sand dunes nearly surrounds the north polar cap. These landforms are located near 80.3oN, 144.1oW. Light-toned features in the image are exposures of the substrate that underlies the dune field. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  4. Imaging with Polarized Neutrons

    Directory of Open Access Journals (Sweden)

    Nikolay Kardjilov

    2018-01-01

    Full Text Available Owing to their zero charge, neutrons are able to pass through thick layers of matter (typically several centimeters while being sensitive to magnetic fields due to their intrinsic magnetic moment. Therefore, in addition to the conventional attenuation contrast image, the magnetic field inside and around a sample can be visualized by detecting changes of polarization in a transmitted beam. The method is based on the spatially resolved measurement of the cumulative precession angles of a collimated, polarized, monochromatic neutron beam that traverses a magnetic field or sample.

  5. The polar mesosphere

    International Nuclear Information System (INIS)

    Morris, Ray; Murphy, Damian

    2008-01-01

    The mesosphere region, which lies at the edge of space, contains the coldest layer of the Earth's atmosphere, with summer temperatures as low as minus 130 °C. In this extreme environment ice aerosol layers have appeared since the dawn of industrialization—whose existence may arguably be linked to human influence—on yet another layer of the Earth's fragile atmosphere. Ground-based and space-based experiments conducted in the Arctic and Antarctic during the International Polar Year (IPY) aim to address limitations in our knowledge and to advance our understanding of thermal and dynamical processes at play in the polar mesosphere

  6. Internal polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, E.R.; Coulter, K.; Gilman, R.; Holt, R.J.; Kowalczyk, R.S.; Napolitano, J.; Potterveld, D.H.; Young, L. (Argonne National Lab., IL (USA)); Mishnev, S.I.; Nikolenko, D.M.; Popov, S.G.; Rachek, I.A.; Temnykh, A.B.; Toporkov, D.K.; Tsentalovich, E.P.; Wojtsekhowski, B.B. (AN SSSR, Novosibirsk (USSR). Inst. Yadernoj Fiziki)

    1989-01-01

    Internal polarized targets offer a number of advantages over external targets. After a brief review of the basic motivation and principles behind internal polarized targets, the technical aspects of the atomic storage cell will be discussed in particular. Sources of depolarization and the means by which their effects can be ameliorated will be described, especially depolarization by the intense magnetic fields arising from the circulating particle beam. The experience of the Argonne Novosibirsk collaboration with the use of a storage cell in a 2 GeV electron storage ring will be the focus of this technical discussion. 17 refs., 11 figs.

  7. AGS polarized H- source

    International Nuclear Information System (INIS)

    Kponou, A.; Alessi, J.G.; Sluyters, T.

    1985-01-01

    The AGS polarized H - source is now operational. During a month-long experimental physics run in July 1984, pulses equivalent to 15 μA x 300 μs (approx. 3 x 10 10 protons) were injected into the RFQ preaccelerator. Beam polarization, measured at 200 MeV, was approx. 75%. After the run, a program to increase the H - yield of the source was begun and significant progress has been made. The H - current is now frequently 20 to 30 μA. A description of the source and some details of our operating experience are given. We also briefly describe the improvement program

  8. ASCI's Vision for supercomputing future

    International Nuclear Information System (INIS)

    Nowak, N.D.

    2003-01-01

    The full text of publication follows. Advanced Simulation and Computing (ASC, formerly Accelerated Strategic Computing Initiative [ASCI]) was established in 1995 to help Defense Programs shift from test-based confidence to simulation-based confidence. Specifically, ASC is a focused and balanced program that is accelerating the development of simulation capabilities needed to analyze and predict the performance, safety, and reliability of nuclear weapons and certify their functionality - far exceeding what might have been achieved in the absence of a focused initiative. To realize its vision, ASC is creating simulation and proto-typing capabilities, based on advanced weapon codes and high-performance computing

  9. Early vision and visual attention

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije P.

    2003-01-01

    Full Text Available The question whether visual perception is spontaneous, sudden or is running through several phases, mediated by higher cognitive processes, was raised ever since the early work of Gestalt psychologists. In the early 1980s, Treisman proposed the feature integration theory of attention (FIT, based on the findings of neuroscience. Soon after publishing her theory a new scientific approach appeared investigating several visual perception phenomena. The most widely researched were the key constructs of FIT, like types of visual search and the role of the attention. The following review describes the main studies of early vision and visual attention.

  10. Information Society Visions in the Nordic Countries

    DEFF Research Database (Denmark)

    Henten, Anders; Kristensen, Thomas Myrup

    2000-01-01

    This paper analyses the information society visions put forward by the governments/administrations of the Nordic countries and compares them to the visions advanced at the EU-level. The paper suggests that the information society visions constitute a kind of common ideology for almost the whole...... political spectrum although it is characterised by a high degree of neo-liberal thinking. It is further argued that there is no distinctly Nordic model for an information society....

  11. The physics of polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    This course is intended to give a description of the basic physical concepts which underlie the study and the interpretation of polarization phenomena. Apart from a brief historical introduction (Sect. 1), the course is organized in three parts. A first part (Sects. 2 - 6) covers the most relevant facts about the polarization phenomena that are typically encountered in laboratory applications and in everyday life. In Sect. 2, the modern description of polarization in terms of the Stokes parameters is recalled, whereas Sect. 3 is devoted to introduce the basic tools of laboratory polarimetry, such as the Jones calculus and the Mueller matrices. The polarization phenomena which are met in the reflection and refraction of a beam of radiation at the separation surface between two dielectrics, or between a dielectric and a metal, are recalled in Sect. 4. Finally, Sect. 5 gives an introduction to the phenomena of dichroism and of anomalous dispersion and Sect. 6 summarizes the polarization phenomena that are commonly encountered in everyday life. The second part of this course (Sects. 7-14) deals with the description, within the formalism of classical physics, of the spectro-polarimetric properties of the radiation emitted by accelerated charges. Such properties are derived by taking as starting point the Liénard and Wiechert equations that are recalled and discussed in Sect. 7 both in the general case and in the non-relativistic approximation. The results are developed to find the percentage polarization, the radiation diagram, the cross-section and the spectral characteristics of the radiation emitted in different phenomena particularly relevant from the astrophysical point of view. The emission of a linear antenna is derived in Sect. 8. The other Sections are devoted to Thomson scattering (Sect. 9), Rayleigh scattering (Sect. 10), Mie scattering (Sect. 11), bremsstrahlung radiation (Sect. 12), cyclotron radiation (Sect. 13), and synchrotron radiation (Sect. 14

  12. Polarized Proton Collisions at RHIC

    CERN Document Server

    Bai, Mei; Alekseev, Igor G; Alessi, James; Beebe-Wang, Joanne; Blaskiewicz, Michael; Bravar, Alessandro; Brennan, Joseph M; Bruno, Donald; Bunce, Gerry; Butler, John J; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Laster, Jonathan S; Lee, Roger C; Luccio, Alfredo U; Luo, Yun; MacKay, William W; Makdisi, Yousef; Marr, Gregory J; Marusic, Al; McIntyre, Gary; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oddo, Peter; Oerter, Brian; Osamu, Jinnouchi; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smith, Kevin T; Svirida, Dima; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Wilinski, Michelle; Zaltsman, Alex; Zelenski, Anatoli; Zeno, Keith; Zhang, S Y

    2005-01-01

    The Relativistic Heavy Ion Collider~(RHIC) provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC to avoid depolarizing resonances. In 2003, polarized proton beams were accelerated to 100~GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. RHIC polarized proton run experience demonstrates that optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limite...

  13. Quality of life in Nepalese patients with low vision and the impact of low vision services

    Directory of Open Access Journals (Sweden)

    Rajendra Gyawali

    2012-10-01

    Conclusions: Low vision patients have poor quality of life as measured with the NEI VFQ-25. Low vision service is associated with improved visual function, better quality of life and high rate of patient satisfaction.

  14. Color in Computer Vision Fundamentals and Applications

    CERN Document Server

    Gevers, Theo; van de Weijer, Joost; Geusebroek, Jan-Mark

    2012-01-01

    While the field of computer vision drives many of today’s digital technologies and communication networks, the topic of color has emerged only recently in most computer vision applications. One of the most extensive works to date on color in computer vision, this book provides a complete set of tools for working with color in the field of image understanding. Based on the authors’ intense collaboration for more than a decade and drawing on the latest thinking in the field of computer science, the book integrates topics from color science and computer vision, clearly linking theor

  15. INNOVATION OF ENTERPRISE VISION TOWARD SOCIAL RESPONSIBILITY

    Directory of Open Access Journals (Sweden)

    Tjaša Štrukelj

    2012-12-01

    Full Text Available Businesses need new bases and methods taking in account new values, culture, ethics, and norms (VCEN of humans, leading both humans and businesses to their own requisite holism. This covers also enterprise governance and management and their predisposition to (responsible enterprise vision (and resulting enterprise policy we studied. Thus we are researching the formation and development of enterprise vision, the period and wholeness of which are relative. In our discussion we originated in different definitions of vision andwe showed a possible development path for it, in order to direct vision towards social responsibility (SR in enterprise behaviour.

  16. Applications of AI, machine vision and robotics

    CERN Document Server

    Boyer, Kim; Bunke, H

    1995-01-01

    This text features a broad array of research efforts in computer vision including low level processing, perceptual organization, object recognition and active vision. The volume's nine papers specifically report on topics such as sensor confidence, low level feature extraction schemes, non-parametric multi-scale curve smoothing, integration of geometric and non-geometric attributes for object recognition, design criteria for a four degree-of-freedom robot head, a real-time vision system based on control of visual attention and a behavior-based active eye vision system. The scope of the book pr

  17. Mining the epigenetic landscape of tissue polarity in search of new targets for cancer therapy.

    Science.gov (United States)

    Atrian, Farzaneh; Lelièvre, Sophie A

    2015-01-01

    The epigenetic nature of cancer encourages the development of inhibitors of epigenetic pathways. Yet, the clinical use for solid tumors of approved epigenetic drugs is meager. We argue that this situation might improve upon understanding the coinfluence between epigenetic pathways and tissue architecture. We present emerging information on the epigenetic control of the polarity axis, a central feature of epithelial architecture created by the orderly distribution of multiprotein complexes at cell-cell and cell-extracellular matrix contacts and altered upon cancer onset (with apical polarity loss), invasive progression (with basolateral polarity loss) and metastatic development (with basoapical polarity imbalance). This information combined with the impact of polarity-related proteins on epigenetic mechanisms of cancer enables us to envision how to guide the choice of drugs specific for distinct epigenetic modifiers, in order to halt cancer development and counter the consequences of polarity alterations.

  18. Arabidopsis AIP1-2 restricted by WER-mediated patterning modulates planar polarity.

    Science.gov (United States)

    Kiefer, Christian S; Claes, Andrea R; Nzayisenga, Jean-Claude; Pietra, Stefano; Stanislas, Thomas; Hüser, Anke; Ikeda, Yoshihisa; Grebe, Markus

    2015-01-01

    The coordination of cell polarity within the plane of the tissue layer (planar polarity) is crucial for the development of diverse multicellular organisms. Small Rac/Rho-family GTPases and the actin cytoskeleton contribute to planar polarity formation at sites of polarity establishment in animals and plants. Yet, upstream pathways coordinating planar polarity differ strikingly between kingdoms. In the root of Arabidopsis thaliana, a concentration gradient of the phytohormone auxin coordinates polar recruitment of Rho-of-plant (ROP) to sites of polar epidermal hair initiation. However, little is known about cytoskeletal components and interactions that contribute to this planar polarity or about their relation to the patterning machinery. Here, we show that ACTIN7 (ACT7) represents a main actin isoform required for planar polarity of root hair positioning, interacting with the negative modulator ACTIN-INTERACTING PROTEIN1-2 (AIP1-2). ACT7, AIP1-2 and their genetic interaction are required for coordinated planar polarity of ROP downstream of ethylene signalling. Strikingly, AIP1-2 displays hair cell file-enriched expression, restricted by WEREWOLF (WER)-dependent patterning and modified by ethylene and auxin action. Hence, our findings reveal AIP1-2, expressed under control of the WER-dependent patterning machinery and the ethylene signalling pathway, as a modulator of actin-mediated planar polarity. © 2015. Published by The Company of Biologists Ltd.

  19. VISION 21 SYSTEMS ANALYSIS METHODOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    G.S. Samuelsen; A. Rao; F. Robson; B. Washom

    2003-08-11

    Under the sponsorship of the U.S. Department of Energy/National Energy Technology Laboratory, a multi-disciplinary team led by the Advanced Power and Energy Program of the University of California at Irvine is defining the system engineering issues associated with the integration of key components and subsystems into power plant systems that meet performance and emission goals of the Vision 21 program. The study efforts have narrowed down the myriad of fuel processing, power generation, and emission control technologies to selected scenarios that identify those combinations having the potential to achieve the Vision 21 program goals of high efficiency and minimized environmental impact while using fossil fuels. The technology levels considered are based on projected technical and manufacturing advances being made in industry and on advances identified in current and future government supported research. Included in these advanced systems are solid oxide fuel cells and advanced cycle gas turbines. The results of this investigation will serve as a guide for the U. S. Department of Energy in identifying the research areas and technologies that warrant further support.

  20. Vision for 2030; Visie 2030

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-02-15

    This is the long term vision of the Dutch Transmission System Operator TenneT with respect to the 380kV and 220 kV parts of the national electricity distribution grid. In this vision 4 trend scenarios have been developed. The scenarios 'Green Revolution' and 'Sustainable transition' are based on a sustainable society whereas 'Money rules' and 'New strongholds' depict a society that mainly depends on fossil fuels. For 'Green revolution' and 'Money rules' a free global market is assumed and for 'Sustainable transition' and 'New strongholds' a regionally oriented market with protectionism is assumed. [mk]. [Dutch] Een langetermijnvisie van de Nederlandse Transmission System Operator TenneT op het 380 kV en 220kV deel van het landelijke elektriciteitstransportnet. Daarvoor zijn vier trendscenario's ontwikkeld. De scenario's Groene Revolutie en Duurzame Transitie gaan uit van een duurzame samenleving terwijl Geld Regeert en Nieuwe Burchten een samenleving hanteert die vooral afhankelijk is van fossiele brandstoffen. Voor Groene Revolutie en Geld Regeert wordt een vrije mondiale markt verondersteld en voor Duurzame Transitie en Nieuwe Burchten een regionaal georienteerde markt waarbij sprake is van protectionisme.

  1. Pengukuran Jarak Berbasiskan Stereo Vision

    Directory of Open Access Journals (Sweden)

    Iman Herwidiana Kartowisastro

    2010-12-01

    Full Text Available Measuring distance from an object can be conducted in a variety of ways, including by making use of distance measuring sensors such as ultrasonic sensors, or using the approach based vision system. This last mode has advantages in terms of flexibility, namely a monitored object has relatively no restrictions characteristic of the materials used at the same time it also has its own difficulties associated with object orientation and state of the room where the object is located. To overcome this problem, so this study examines the possibility of using stereo vision to measure the distance to an object. The system was developed starting from image extraction, information extraction characteristics of the objects contained in the image and visual distance measurement process with 2 separate cameras placed in a distance of 70 cm. The measurement object can be in the range of 50 cm - 130 cm with a percentage error of 5:53%. Lighting conditions (homogeneity and intensity has a great influence on the accuracy of the measurement results. 

  2. Early vision and focal attention

    Science.gov (United States)

    Julesz, Bela

    1991-07-01

    At the thirty-year anniversary of the introduction of the technique of computer-generated random-dot stereograms and random-dot cinematograms into psychology, the impact of the technique on brain research and on the study of artificial intelligence is reviewed. The main finding-that stereoscopic depth perception (stereopsis), motion perception, and preattentive texture discrimination are basically bottom-up processes, which occur without the help of the top-down processes of cognition and semantic memory-greatly simplifies the study of these processes of early vision and permits the linking of human perception with monkey neurophysiology. Particularly interesting are the unexpected findings that stereopsis (assumed to be local) is a global process, while texture discrimination (assumed to be a global process, governed by statistics) is local, based on some conspicuous local features (textons). It is shown that the top-down process of "shape (depth) from shading" does not affect stereopsis, and some of the models of machine vision are evaluated. The asymmetry effect of human texture discrimination is discussed, together with recent nonlinear spatial filter models and a novel extension of the texton theory that can cope with the asymmetry problem. This didactic review attempts to introduce the physicist to the field of psychobiology and its problems-including metascientific problems of brain research, problems of scientific creativity, the state of artificial intelligence research (including connectionist neural networks) aimed at modeling brain activity, and the fundamental role of focal attention in mental events.

  3. Computer vision syndrome: A review.

    Science.gov (United States)

    Gowrisankaran, Sowjanya; Sheedy, James E

    2015-01-01

    Computer vision syndrome (CVS) is a collection of symptoms related to prolonged work at a computer display. This article reviews the current knowledge about the symptoms, related factors and treatment modalities for CVS. Relevant literature on CVS published during the past 65 years was analyzed. Symptoms reported by computer users are classified into internal ocular symptoms (strain and ache), external ocular symptoms (dryness, irritation, burning), visual symptoms (blur, double vision) and musculoskeletal symptoms (neck and shoulder pain). The major factors associated with CVS are either environmental (improper lighting, display position and viewing distance) and/or dependent on the user's visual abilities (uncorrected refractive error, oculomotor disorders and tear film abnormalities). Although the factors associated with CVS have been identified the physiological mechanisms that underlie CVS are not completely understood. Additionally, advances in technology have led to the increased use of hand-held devices, which might impose somewhat different visual challenges compared to desktop displays. Further research is required to better understand the physiological mechanisms underlying CVS and symptoms associated with the use of hand-held and stereoscopic displays.

  4. Lobbying and political polarization

    OpenAIRE

    Ursprung, Heinrich W.

    2002-01-01

    Standard spatial models of political competition give rise to equilibria in which the competing political parties or candidates converge to a common position. In this paper I show how political polarization can be generated in models that focus on the nexus between pre-election interest group lobbying and electoral competition.

  5. Fluorescence confocal polarizing microscopy

    Indian Academy of Sciences (India)

    Much of the modern understanding of orientational order in liquid crystals (LCs) is based on polarizing microscopy (PM). A PM image bears only two-dimensional (2D) information, integrating the 3D pattern of optical birefringence over the path of light. Recently, we proposed a technique to image 3D director patterns by ...

  6. Polarization of Bremsstrahlung

    International Nuclear Information System (INIS)

    Miller, J.

    1957-01-01

    The numerical results for the polarization of Bremsstrahlung are presented. The multiple scattering of electrons in the target is taken into account. The angular-and photon energy dependences are seen on the curves for an incident 25 MeV electron energy. (Author) [fr

  7. DESY: HERA polarization

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The new HERA electron-proton collider at DESY in Hamburg achieved the first luminosity for electron-proton collisions on 19 October last year. Only one month later, on 20 November, HERA passed another important milestone with the observation of transverse electron polarization

  8. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  9. Graphics of polar figure

    International Nuclear Information System (INIS)

    Macias B, L.R.

    1991-11-01

    The objective of this work, is that starting from a data file coming from a spectra that has been softened, and of the one that have been generated its coordinates to project it in stereographic form, to create the corresponding polar figure making use of the Cyber computer of the ININ by means of the GRAPHOS package. This work only requires a Beta, Fi and Intensity (I) enter data file. It starts of the existence of a softened spectra of which have been generated already with these data, making use of some language that in this case was FORTRAN for the Cyber computer, a program is generated supported in the Graphos package that allows starting of a reading of the Beta, Fi, I file, to generate the points in a stereographic projection and that it culminates with the graph of the corresponding polar figure. The program will request the pertinent information that is wanted to capture in the polar figure just as: date, name of the enter file, indexes of the polar figure, number of levels, radio of the stereographic projection (cms.), crystalline system to which belongs the sample, name the neuter graph file by create and to add the own general data. (Author)

  10. Managing Dreams and Ambitions: A Psychological Analysis of Vision Communication

    NARCIS (Netherlands)

    D.A. Stam (Daan)

    2008-01-01

    textabstractThe communication of inspiring visions is arguably the sine qua non of change-oriented leadership. Visions are images of the future. Vision communication refers to the expression of a vision with the aim of convincing others (usually followers) that the vision is valid. Despite the fact

  11. Visions for Danish bio-ethanol; Visioner for dansk bioethanol

    Energy Technology Data Exchange (ETDEWEB)

    Ahring, B.K. [BioCentrum-DTU (Denmark); Felby, C. [Det Biovidenskabelige Fakultet -KU (Denmark); Jensen, Arne [Syddansk Univ., Ledelsessekretariatet (Denmark); Nielsen, Charles [DONG Energy (Denmark); Skytte, K. [Risoe National Lab., System Analysis Dept. - DTU (Denmark); Wormslev, E.C. [NIRAS A/S (Denmark); Zinck, A.M. [Dansk Landbrug (DK)] (eds.)

    2007-02-15

    In 2006 the Danish Academy of Technical Sciences set up a working group to prepare a brief and factual presentation of visions for Danish bioenergy targeted at political actors in that area. This report presents the working group's conclusions and recommendations with focus on bioethanol. Denmark has powerful actors and good opportunities to develop and commercialize this particular type of biofuel. Bioethanol has the potential to create large gains for Denmark within supply, environment and export, and the working group considers bioethanol to be the only alternative to petrol for the transport sector in the short term. However, in order to establish Denmark as a strong and relevant partner in international development, it is crucial for the Danish actors to concentrate on a joint effort. (BA)

  12. Vision as subjective perception; La vision, une perception subjective

    Energy Technology Data Exchange (ETDEWEB)

    Reppas, J.B. [Harvard Univ., Cambridge, MA (United States). Biological Labs.; Dale, A.; Sereno, M.; Tootell, R.

    1996-07-01

    The human brain is not very different of the monkey`s one: at least, its visual cortex is organized as a similar scheme. Specialized areas in the movement analysis are found and others in the forms perception. In this work, the author tries to answer to the following questions: (1)why so many visual areas? What are exactly their role in vision? Thirteen years of experimentation have not allowed to answer to these questions. The cerebral NMR imaging gives the opportunity of understanding the subjective perception of the visual world. One step which is particularly described in this work is to know how the visual cortex reacts to the optical illusions. (O.M.).

  13. Characteristics of volume polarization holography with linear polarization light

    Science.gov (United States)

    Zang, Jinliang; Wu, An'an; Liu, Ying; Wang, Jue; Lin, Xiao; Tan, Xiaodi; Shimura, Tsutomu; Kuroda, Kazuo

    2015-10-01

    Volume polarization holographic recording in phenanthrenequinone-doped poly(methyl methacrylate) (PQ-PMMA) photopolymer with linear polarized light is obtained. The characteristics of the volume polarization hologram are experimentally investigated. It is found that beyond the paraxial approximation the polarization states of the holographic reconstruction light are generally different from the signal light. Based on vector wave theoretical analyses and material properties, the special exposure condition for correctly holographic reconstruction is obtained and experimentally demonstrated.

  14. Buildings of the Future Scoping Study: A Framework for Vision Development

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Na [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Goins, John D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-02-01

    The Buildings of the Future Scoping Study, funded by the U.S. Department of Energy (DOE) Building Technologies Office, seeks to develop a vision for what U.S. mainstream commercial and residential buildings could become in 100 years. This effort is not intended to predict the future or develop a specific building design solution. Rather, it will explore future building attributes and offer possible pathways of future development. Whether we achieve a more sustainable built environment depends not just on technologies themselves, but on how effectively we envision the future and integrate these technologies in a balanced way that generates economic, social, and environmental value. A clear, compelling vision of future buildings will attract the right strategies, inspire innovation, and motivate action. This project will create a cross-disciplinary forum of thought leaders to share their views. The collective views will be integrated into a future building vision and published in September 2015. This report presents a research framework for the vision development effort based on a literature survey and gap analysis. This document has four objectives. First, it defines the project scope. Next, it identifies gaps in the existing visions and goals for buildings and discusses the possible reasons why some visions did not work out as hoped. Third, it proposes a framework to address those gaps in the vision development. Finally, it presents a plan for a series of panel discussions and interviews to explore a vision that mitigates problems with past building paradigms while addressing key areas that will affect buildings going forward.

  15. Experiments with Fermilab polarized proton and polarized antiproton beams

    International Nuclear Information System (INIS)

    Yokosawa, A.

    1990-01-01

    We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized-beam facility, measurements of beam polarization by polarimeters, asymmetry measurements in the π degree production at high p perpendicular and in the Λ (Σ degree), π ± , π degree production at large x F , and Δσ L (pp, bar pp) measurements. 18 refs

  16. NUCLEON POLARIZATION IN 3-BODY MODELS OF POLARIZED LI-6

    NARCIS (Netherlands)

    SCHELLINGERHOUT, NW; KOK, LP; COON, SA; ADAM, RM

    1993-01-01

    Just as He-3 --> can be approximately characterized as a polarized neutron target, polarized Li-6D has been advocated as a good isoscalar nuclear target for the extraction of the polarized gluon content of the nucleon. The original argument rests upon a presumed ''alpha + deuteron'' picture of Li-6,

  17. Geomagnetic polarity transitions

    Science.gov (United States)

    Merrill, Ronald T.; McFadden, Phillip L.

    1999-05-01

    The top of Earth's liquid outer core is nearly 2900 km beneath Earth's surface, so we will never be able to observe it directly. This hot, dense, molten iron-rich body is continuously in motion and is the source of Earth's magnetic field. One of the most dynamic manifestations at Earth's surface of this fluid body is, perhaps, a reversal of the geomagnetic field. Unfortunately, the most recent polarity transition occurred at about 780 ka, so we have never observed a transition directly. It seems that a polarity transition spans many human lifetimes, so no human will ever witness the phenomenon in its entirety. Thus we are left with the tantalizing prospect that paleomagnetic records of polarity transitions may betray some of the secrets of the deep Earth. Certainly, if there are systematics in the reversal process and they can be documented, then this will reveal substantial information about the nature of the lowermost mantle and of the outer core. Despite their slowness on a human timescale, polarity transitions occur almost instantaneously on a geological timescale. This rapidity, together with limitations in the paleomagnetic recording process, prohibits a comprehensive description of any reversal transition both now and into the foreseeable future, which limits the questions that may at this stage be sensibly asked. The natural model for the geomagnetic field is a set of spherical harmonic components, and we are not able to obtain a reliable model for even the first few harmonic terms during a transition. Nevertheless, it is possible, in principle, to make statements about the harmonic character of a geomagnetic polarity transition without having a rigorous spherical harmonic description of one. For example, harmonic descriptions of recent geomagnetic polarity transitions that are purely zonal can be ruled out (a zonal harmonic does not change along a line of latitude). Gleaning information about transitions has proven to be difficult, but it does seem

  18. Retracing the path of planar cell polarity.

    Science.gov (United States)

    Schenkelaars, Quentin; Fierro-Constain, Laura; Renard, Emmanuelle; Borchiellini, Carole

    2016-04-02

    The Planar Cell Polarity pathway (PCP) has been described as the main feature involved in patterning cell orientation in bilaterian tissues. Recently, a similar phenomenon was revealed in cnidarians, in which the inhibition of this pathway results in the absence of cilia orientation in larvae, consequently proving the functional conservation of PCP signaling between Cnidaria and Bilateria. Nevertheless, despite the growing accumulation of databases concerning basal lineages of metazoans, very few information concerning the existence of PCP components have been gathered outside of Bilateria and Cnidaria. Thus, the origin of this module or its prevalence in early emerging metazoans has yet to be elucidated. The present study addresses this question by investigating the genomes and transcriptomes from all poriferan lineages in addition to Trichoplax (Placozoa) and Mnemiopsis (Ctenophora) genomes for the presence of the core components of this pathway. Our results confirm that several PCP components are metazoan innovations. In addition, we show that all members of the PCP pathway, including a bona fide Strabismus ortholog (Van gogh), are retrieved only in one sponge lineage (Homoscleromorpha) out of four. This highly suggests that the full PCP pathway dates back at least to the emergence of homoscleromorph sponges. Consequently, several secondary gene losses would have occurred in the three other poriferan lineages including Amphimedon queenslandica (Demospongiae). Several proteins were not retrieved either in placozoans or ctenophores leading us to discuss the difficulties to predict orthologous proteins in basally branching animals. Finally, we reveal how the study of multigene families may be helpful to unravel the relationships at the base of the metazoan tree. The PCP pathway antedates the radiation of Porifera and may have arisen in the last common ancestor of animals. Oscarella species now appear as key organisms to understand the ancestral function of PCP

  19. Polarized electron beams at SLAC

    International Nuclear Information System (INIS)

    Moffeit, K.C.

    1992-11-01

    SLAC has successfully accelerated high energy polarized electrons for the Stanford Linear Collider and fixed polarized nuclear target experiments. The polarized electron beams at SLAC use a gallium arsenide (GaAlAs for E-142) photon emission source to provide the beam of polarized electrons with polarization of approximately 28% (41% for E-142). While the beam emittance is reduced in the damping ring for SLC operation a system of bend magnets and superconducting solenoids preserve and orient the spin direction for maximum longitudinal polarization at the collision point. The electron polarization is monitored with a Compton scattering polarimeter, and was typically 22% at the e+e- collision point for the 1992 run. Improvements are discussed to increase the source polarization and to reduce the depolarization effects between the source and the collision point

  20. Analytical polarization calculations beyond SLIM

    International Nuclear Information System (INIS)

    Barber, D.P.

    1989-01-01

    A comparison is made between the theories of Bell and Leinaas and of Derbenev and Kondratenko for the spin polarization in electron storage rings. A calculation of polarization in HERA using the program SMILE of Mane is presented

  1. CHARACTERISTICS OF THE NIGERIAN LOW VISION POPULATION

    African Journals Online (AJOL)

    INTRODUCTION. The World Health organization (WHO) has recently estimated in 2002, that there were 161 million visually impaired persons worldwide the vast majority of whom are in developing countries. (report of Oslo workshop, 2004). Low vision services, when made available to people with low vision, they can ...

  2. Assessing the binocular advantage in aided vision.

    Science.gov (United States)

    Harrington, Lawrence K; McIntire, John P; Hopper, Darrel G

    2014-09-01

    Advances in microsensors, microprocessors, and microdisplays are creating new opportunities for improving vision in degraded environments through the use of head-mounted displays. Initially, the cutting-edge technology used in these new displays will be expensive. Inevitably, the cost of providing the additional sensor and processing required to support binocularity brings the value of binocularity into question. Several assessments comparing binocular, binocular, and monocular head-mounted displays for aided vision have concluded that the additional performance, if any, provided by binocular head-mounted displays does not justify the cost. The selection of a biocular [corrected] display for use in the F-35 is a current example of this recurring decision process. It is possible that the human binocularity advantage does not carry over to the aided vision application, but more likely the experimental approaches used in the past have been too coarse to measure its subtle but important benefits. Evaluating the value of binocularity in aided vision applications requires an understanding of the characteristics of both human vision and head-mounted displays. With this understanding, the value of binocularity in aided vision can be estimated and experimental evidence can be collected to confirm or reject the presumed binocular advantage, enabling improved decisions in aided vision system design. This paper describes four computational approaches-geometry of stereopsis, modulation transfer function area for stereopsis, probability summation, and binocular summation-that may be useful in quantifying the advantage of binocularity in aided vision.

  3. Implementing Vision Research in Special Needs Education

    Science.gov (United States)

    Wilhelmsen, Gunvor Birkeland; Aanstad, Monica L.; Leirvik, Eva Iren B.

    2015-01-01

    This article presents experiences from vision research implemented in education and argues for the need for teachers with visual competence and insight into suitable methods for stimulation and learning. A new type of continuing professional development (CPD) focuses on the role of vision in children's learning and development, the consequences of…

  4. A vision for modernizing environmental risk assessment

    Science.gov (United States)

    In 2007, the US National Research Council (NRC) published a Vision and Strategy for [human health] Toxicity Testing in the 21st century. Central to the vision was increased reliance on high throughput in vitro testing and predictive approaches based on mechanistic understanding o...

  5. Vision: A Conceptual Framework for School Counselors

    Science.gov (United States)

    Watkinson, Jennifer Scaturo

    2013-01-01

    Vision is essential to the implementation of the American School Counselor Association (ASCA) National Model. Drawing from research in organizational leadership, this article provides a conceptual framework for how school counselors can incorporate vision as a strategy for implementing school counseling programs within the context of practice.…

  6. Community identities as visions for landscape change

    Science.gov (United States)

    William P. Stewart; Derek Liebert; Kevin W. Larkin

    2004-01-01

    Residents' felt senses of their community can play substantial roles in determining visions for landscape change. Community identities are often anchored in tangible environments and events of a community, and have the potential to serve as visions for landscape planning processes. Photo-elicitation is applied in this study to connect community-based meanings to...

  7. Investigating Teachers' Personal Visions and Beliefs: Implications ...

    African Journals Online (AJOL)

    Visions and beliefs are assumed to always shape his/her perception, attitude, focus and performance. The growing influence of constructivism in teacher education and the increase in the amount of research into teacher cognition has put the notion of beliefs and vision into central focus such that it is fast becoming a ...

  8. Genetics Home Reference: color vision deficiency

    Science.gov (United States)

    ... of L or M cones or to the production of abnormal opsin pigments in these cones that affect red-green color vision. Blue-yellow color vision defects result from mutations in the ... the production of defective S cones. Impaired S cone function alters perception ...

  9. Color vision: introduction by the feature editors.

    Science.gov (United States)

    Buck, Steven L; Baraas, Rigmor; Lee, Barry B; Lindsey, Delwin T; Uchikawa, Keiji; Webster, Michael A; Werner, John S

    2016-03-01

    This feature issue of the Journal of the Optical Society of America A (JOSA A) reflects the basic and applied research interests of members of the color vision community. Most of the articles stem from presentations at the 23rd Biennial Symposium of the International Colour Vision Society (ICVS).

  10. Without a Vision the People Perish.

    Science.gov (United States)

    Casey, John

    2002-01-01

    Discusses ways in which Catholic schools can reflect on the Catholic vision and identity within the institution. Reminds Catholic educators that the Catholic vision includes personal and societal transformation in the light of the Gospel. Suggests particular consideration is due the areas of leadership training, social justice, and spiritual life.…

  11. Literacy skills of children with low vision

    NARCIS (Netherlands)

    Gompel, M.

    2005-01-01

    The main question of the studies reported in this thesis is how the reading and spelling skills of children with low vision compare to those of their sighted peers, and which factors determine the variation in reading and spelling ability in children with low vision. In the study reported in chapter

  12. Pre-attentive and attentive vision module

    NARCIS (Netherlands)

    Nyamsuren, Enkhbold; Taatgen, Niels A.

    This paper introduces a new vision module, called PAAV, developed for the cognitive architecture ACT-R. Unlike ACT-R's default vision module that was originally developed for top-down perception only, PAAV was designed to model a wide range of tasks, such as visual search and scene viewing, where

  13. On Determinants of Political Polarization

    OpenAIRE

    Grechyna, Daryna

    2015-01-01

    Political polarization has been shown to significantly influence a country's economic performance. However, little is known about the drivers of political polarization. In this article, we aim to identify the main determinants of political polarization using Bayesian Model Averaging to overcome the problem of model uncertainty. We find that the level of trust within a country and the degree of income inequality are the most robust determinants of political polarization.

  14. Refractory neural nets and vision

    Science.gov (United States)

    Fall, Thomas C.

    2014-02-01

    Biological understandings have served as the basis for new computational approaches. A prime example is artificial neural nets which are based on the biological understanding of the trainability of neural synapses. In this paper, we will investigate features of the biological vision system to see if they can also be exploited. These features are 1) the neuron's refractory period - the period of time after the neuron fires before it can fire again and 2) the ocular microtremor which moves the retinal neural array relative to the image. The short term memory due to the refractory period allows the before and after movement views to be compared. This paper will discuss the investigation of the implications of these two features.

  15. MR imaging and computer vision

    International Nuclear Information System (INIS)

    Gerig, G.; Kikinis, R.; Kuoni, W.

    1989-01-01

    To parallel the rapid progress in MR data acquisition, the authors have developed advanced computer vision methods specifically adapted to the multidimensional and multispectral (T1- and T2-weighted) nature of MR data to extract, analyze, and visualize the morphologic properties of biologic tissues. A multistage image processing scheme is proposed, which performs the three-dimensional (3D) segmentation of the brain (gray and white matter) and ventricular system from two-echo MR volume data with only minimal user interaction. The quality of the segmentation demonstrates the high potential of MR acquisition along with 3D segmentation and 3D visualization for diagnosis, preoperative planning, and research. With segmentation, a fully quantitative 3D exploration is accessible

  16. Development of Moire machine vision

    Science.gov (United States)

    Harding, Kevin G.

    1987-01-01

    Three dimensional perception is essential to the development of versatile robotics systems in order to handle complex manufacturing tasks in future factories and in providing high accuracy measurements needed in flexible manufacturing and quality control. A program is described which will develop the potential of Moire techniques to provide this capability in vision systems and automated measurements, and demonstrate artificial intelligence (AI) techniques to take advantage of the strengths of Moire sensing. Moire techniques provide a means of optically manipulating the complex visual data in a three dimensional scene into a form which can be easily and quickly analyzed by computers. This type of optical data manipulation provides high productivity through integrated automation, producing a high quality product while reducing computer and mechanical manipulation requirements and thereby the cost and time of production. This nondestructive evaluation is developed to be able to make full field range measurement and three dimensional scene analysis.

  17. New Media Vision for IYA

    Science.gov (United States)

    Gay, P. L.; Koppelman, M.

    2008-11-01

    The International Year of Astronomy New Media Committee seeks to provide and promote online astronomy experiences in the places that people work, play and learn; create content that will expose people to astronomy, provide them regular content, and create special opportunities for learning; distribute content for active (pull) and passive (push) channels and through guerilla marketing technique; use a diverse suite of technologies to reach people on multiple platforms and in diverse online settings. To make these goals a reality we have brought together a diverse group of astronomy new media practitioners to both mentor grass roots efforts and spearhead national initiatives. You are invited to partner you programs with the New Media Task Group. In this paper we lay out are goals and define our vision.

  18. Une nouvelle vision du monde

    CERN Multimedia

    CERN. Geneva

    2008-01-01

    L'histoire des sciences de l'univers et des sciences de la matière est marquée par un petit nombre de « révolutions » qui ont fait basculer notre compréhension de l'infiniment grand et de l'infiniment petit. Ces nouvelles visions du monde ont été déclenchées tantôt par des avancées conceptuelles, tantôt par des innovations instrumentales. Qu'en est-il en ce début de XXIe siècle ? Les grands projets instrumentaux, comme le LHC ou les détecteurs d'ondes gravitationnelles, ouvrent-ils la voie à une nouvelle révolution scientifique ?

  19. Yarbus, Eye Movements, and Vision

    Directory of Open Access Journals (Sweden)

    Benjamin W Tatler

    2010-04-01

    Full Text Available The impact of Yarbus's research on eye movements was enormous following the translation of his book Eye Movements and Vision into English in 1967. In stark contrast, the published material in English concerning his life is scant. We provide a brief biography of Yarbus and assess his impact on contemporary approaches to research on eye movements. While early interest in his work focused on his study of stabilised retinal images, more recently this has been replaced with interest in his work on the cognitive influences on scanning patterns. We extended his experiment on the effect of instructions on viewing a picture using a portrait of Yarbus rather than a painting. The results obtained broadly supported those found by Yarbus.

  20. Dense image correspondences for computer vision

    CERN Document Server

    Liu, Ce

    2016-01-01

    This book describes the fundamental building-block of many new computer vision systems: dense and robust correspondence estimation. Dense correspondence estimation techniques are now successfully being used to solve a wide range of computer vision problems, very different from the traditional applications such techniques were originally developed to solve. This book introduces the techniques used for establishing correspondences between challenging image pairs, the novel features used to make these techniques robust, and the many problems dense correspondences are now being used to solve. The book provides information to anyone attempting to utilize dense correspondences in order to solve new or existing computer vision problems. The editors describe how to solve many computer vision problems by using dense correspondence estimation. Finally, it surveys resources, code, and data necessary for expediting the development of effective correspondence-based computer vision systems.   ·         Provides i...

  1. Soft Computing Techniques in Vision Science

    CERN Document Server

    Yang, Yeon-Mo

    2012-01-01

    This Special Edited Volume is a unique approach towards Computational solution for the upcoming field of study called Vision Science. From a scientific firmament Optics, Ophthalmology, and Optical Science has surpassed an Odyssey of optimizing configurations of Optical systems, Surveillance Cameras and other Nano optical devices with the metaphor of Nano Science and Technology. Still these systems are falling short of its computational aspect to achieve the pinnacle of human vision system. In this edited volume much attention has been given to address the coupling issues Computational Science and Vision Studies.  It is a comprehensive collection of research works addressing various related areas of Vision Science like Visual Perception and Visual system, Cognitive Psychology, Neuroscience, Psychophysics and Ophthalmology, linguistic relativity, color vision etc. This issue carries some latest developments in the form of research articles and presentations. The volume is rich of contents with technical tools ...

  2. Vision based systems for UAV applications

    CERN Document Server

    Kuś, Zygmunt

    2013-01-01

    This monograph is motivated by a significant number of vision based algorithms for Unmanned Aerial Vehicles (UAV) that were developed during research and development projects. Vision information is utilized in various applications like visual surveillance, aim systems, recognition systems, collision-avoidance systems and navigation. This book presents practical applications, examples and recent challenges in these mentioned application fields. The aim of the book is to create a valuable source of information for researchers and constructors of solutions utilizing vision from UAV. Scientists, researchers and graduate students involved in computer vision, image processing, data fusion, control algorithms, mechanics, data mining, navigation and IC can find many valuable, useful and practical suggestions and solutions. The latest challenges for vision based systems are also presented.

  3. Fine structure and optical properties of biological polarizers in crustaceans and cephalopods

    Science.gov (United States)

    Chiou, Tsyr-Huei; Caldwell, Roy L.; Hanlon, Roger T.; Cronin, Thomas W.

    2008-04-01

    The lighting of the underwater environment is constantly changing due to attenuation by water, scattering by suspended particles, as well as the refraction and reflection caused by the surface waves. These factors pose a great challenge for marine animals which communicate through visual signals, especially those based on color. To escape this problem, certain cephalopod mollusks and stomatopod crustaceans utilize the polarization properties of light. While the mechanisms behind the polarization vision of these two animal groups are similar, several distinctive types of polarizers (i.e. the structure producing the signal) have been found in these animals. To gain a better knowledge of how these polarizers function, we studied the relationships between fine structures and optical properties of four types of polarizers found in cephalopods and stomatopods. Although all the polarizers share a somewhat similar spectral range, around 450- 550 nm, the reflectance properties of the signals and the mechanisms used to produce them have dramatic differences. In cephalopods, stack-plates polarizers produce the polarization patterns found on the arms and around their eyes. In stomatopods, we have found one type of beam-splitting polarizer based on photonic structures and two absorptive polarizer types based on dichroic molecules. These stomatopod polarizers may be found on various appendages, and on the cuticle covering dorsal or lateral sides of the animal. Since the efficiencies of all these polarizer types are somewhat sensitive to the change of illumination and viewing angle, how these animals compensate with different behaviors or fine structural features of the polarizer also varies.

  4. Optics, illumination, and image sensing for machine vision II

    International Nuclear Information System (INIS)

    Svetkoff, D.J.

    1987-01-01

    These proceedings collect papers on the general subject of machine vision. Topics include illumination and viewing systems, x-ray imaging, automatic SMT inspection with x-ray vision, and 3-D sensing for machine vision

  5. Polarized electrogowdy spacetimes censored

    Energy Technology Data Exchange (ETDEWEB)

    Nungesser, Ernesto, E-mail: ernesto.nungesser@aei.mpg.d [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, 14476 Potsdam (Germany)

    2010-05-01

    A sketch of the proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum Gowdy spacetimes. Using this it is seen that the results of Ringstroem on strong cosmic censorship in the vacuum case have implications for the Einstein-Maxwell case. Working out the geometrical meaning of these analytical results leads to the main conclusion.

  6. Polarity controlled reaction path and kinetics of thermal cis-to-trans isomerization of 4-aminoazobenzene.

    Science.gov (United States)

    Joshi, Neeraj Kumar; Fuyuki, Masanori; Wada, Akihide

    2014-02-20

    Spectral and kinetic behavior of thermal cis-to-trans isomerization of 4-aminoazobenzene (AAB) is examined in various solvents of different polarities. In contrast to azobenzene (AB), it is found the rate of thermal isomerization of AAB is highly dependent on solvent polarity. Accelerated rates are observed in polar solvents as compared to nonpolar solvents. Moreover, a decrease in the barrier height with an increase in medium polarity is observed. Our observations suggest that inversion is the preferred pathway in cis-to-trans thermal isomerization in a nonpolar medium; however, in a polar medium, the isomerization path deviates from the inversion route and rotational behavior is incorporated. Differences in the kinetics and in mechanisms of isomerization in different media are rationalized in terms of modulation in barrier height by polarity of the medium and solute-solvent interaction. It is found that kinetics as well as the mechanism of thermal isomerization in AAB is controlled by the polarity of the medium.

  7. Polarization induced doped transistor

    Science.gov (United States)

    Xing, Huili; Jena, Debdeep; Nomoto, Kazuki; Song, Bo; Zhu, Mingda; Hu, Zongyang

    2016-06-07

    A nitride-based field effect transistor (FET) comprises a compositionally graded and polarization induced doped p-layer underlying at least one gate contact and a compositionally graded and doped n-channel underlying a source contact. The n-channel is converted from the p-layer to the n-channel by ion implantation, a buffer underlies the doped p-layer and the n-channel, and a drain underlies the buffer.

  8. Polar bears, Ursus maritimus

    Science.gov (United States)

    Rode, Karyn D.; Stirling, Ian

    2017-01-01

    Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

  9. Polarized advanced fuel reactors

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1987-07-01

    The d- 3 He reaction has the same spin dependence as the d-t reaction. It produces no neutrons, so that if the d-d reactivity could be reduced, it would lead to a neutron-lean reactor. The current understanding of the possible suppression of the d-d reactivity by spin polarization is discussed. The question as to whether a suppression is possible is still unresolved. Other advanced fuel reactions are briefly discussed. 11 refs

  10. On polarization in biomembranes

    DEFF Research Database (Denmark)

    Zecchi, Karis Amata

    close to physiological conditions, making these effects biologically relevant. In this work, we consider the case of asymmetric membranes which can display spontaneous polarization in the absence of a field. Close to the phase transition, we find that the membrane displays piezoelectric, flexoelectric...... on different geometries point in the direction of a flexoelectric mechanism behind current rectification in lipid bilayers. Finally, we suggest that our updated equivalent circuit should be included in the interpretation of elctrophysiological data....

  11. Multifrequency Behaviour of Polars

    Directory of Open Access Journals (Sweden)

    K. Reinsch

    2015-02-01

    Full Text Available Cataclysmic variables emit over a wide range of the electromagnetic spectrum. In this paper I will review observations of polars in relevant passbands obtained during the last decade and will discuss their diagnostical potential to access the physics of the main components within the binary systems. This will include a discussion of intrinsic source variability and the quest for simultaneous multi-frequency observations.

  12. Polar Business Design

    Directory of Open Access Journals (Sweden)

    Sébastien Caisse

    2014-02-01

    Full Text Available Polar business design aims to enable entrepreneurs, managers, consultants, researchers, and business students to better tackle model-based analysis, creation, and transformation of businesses, ventures, and, more generically, collective endeavors of any size and purpose. It is based on a systems-thinking approach that builds on a few interrelated core concepts to create holistic visual frameworks. These core concepts act as poles linked by meaningful dyads, flows, and faces arranged in geometric shapes. The article presents two such polar frameworks as key findings in an ongoing analytic autoethnography: the three-pole Value−Activity−Stakeholder (VAS triquetra and the four-pole Offer−Creation−Character−Stakeholder (OCCS tetrahedron. The VAS triquetra is a more aggregated model of collective endeavors. The OCCS tetrahedron makes a trade-off between a steeper learning curve and deeper, richer representation potential. This article discusses how to use these two frameworks as well as their limits, and explores the potential that polar business design offers for future research.

  13. The Fly Sensitizing Pigment Enhances UV Spectral Sensitivity While Preventing Polarization-Induced Artifacts

    Directory of Open Access Journals (Sweden)

    Marko Ilić

    2018-02-01

    Full Text Available Microvillar photoreceptors are intrinsically capable of detecting the orientation of e-vector of linearly polarized light. They provide most invertebrates with an additional sensory channel to detect important features of their visual environment. However, polarization sensitivity (PS of photoreceptors may lead to the detection of polarization-induced false colors and intensity contrasts. Most insect photoreceptors are thus adapted to have minimal PS. Flies have twisted rhabdomeres with microvilli rotated along the length of the ommatidia to reduce PS. The additional UV-absorbing sensitizing pigment on their opsin minimizes PS in the ultraviolet. We recorded voltage from Drosophila photoreceptors R1–6 to measure the spectral dependence of PS and found that PS in the UV is invariably negligible but can be substantial above 400 nm. Using modeling, we demonstrate that in R1–6 without the sensitizing pigment, PS in the UV (PSUV would exceed PS in the visible part of the spectrum (PSVIS by a factor PSUV/PSVIS = 1.2–1.8, as lower absorption of Rh1 rhodopsin reduces self-screening. We use polarimetric imaging of objects relevant to fly polarization vision to show that their degree of polarization outdoors is highest in the short-wavelength part of the spectrum. Thus, under natural illumination, the sensitizing pigment in R1–6 renders even those cells with high PS in the visible part unsuitable for proper polarization vision. We assume that fly ventral polarization vision can be mediated by R7 alone, with R1–6 serving as an unpolarized reference channel.

  14. Visions of our Planet's Atmosphere, Land & Oceans

    Science.gov (United States)

    Hasler, Arthur F.

    2002-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to South Africa, Cape Town and Johannesburg using NASA Terra MODIS data, Landsat data and 1m IKONOS "Spy Satellite" data. Zoom in to any place South Africa using Earth Viewer 3D from Keyhole Inc. and Landsat data at 30 m resolution. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we present science to the public. See dust storms and flooding in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the north and south polar ice packs and with icebergs on the coasts of Greenland and off the coast of Antarctica. Spectacular new visualizations of the global land, atmosphere & oceans are shown. Listen to the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth

  15. Pediatric vision screening using binocular retinal birefringencr scanning

    Science.gov (United States)

    Nassif, Deborah S.; Gramatikov, Boris; Guyton, David L.; Hunter, David G.

    2003-07-01

    Amblyopia, a leading cause of vision loss in childhood, is responsive to treatment if detected early in life. Risk factors for amblyopia, such as refractive error and strabismus, may be difficult to identify clinically in young children. Our laboratory has developed retinal birefringence scanning (RBS), in which a small spot of polarized light is scanned in a circle on the retina, and the returning light is measured for changes in polarization caused by the pattern of birefringent fibers that comprise the fovea. Binocular RBS (BRBS) detects the fixation of both eyes simultaneously and thus screens for strabismus, one of the risk factors of amblyopia. We have also developed a technique to automatically detect when the eye is in focus without measuring refractive error. This focus detection system utilizes a bull's eye photodetector optically conjugate to a point fixation source. Reflected light is focused back to the point source by the optical system of the eye, and if the subject focuses on the fixation source, the returning light will be focused on the detector. We have constructed a hand-held prototype combining BRBS and focus detection measurements in one quick (< 0.5 second) and accurate (theoretically detecting +/-1 of misalignment) measurement. This approach has the potential to reliably identify children at risk for amblyopia.

  16. Shadows Along the Spiritual Pathway.

    Science.gov (United States)

    Humphrey, Caroline

    2015-12-01

    Contemporary spirituality discourses tend to assume that a canopy of light and love overarches all spiritual pathways. Unfortunately, the dark side of humanity cannot be spirited away so easily, and aberrations of personal spiritual development, interpersonal spiritual relationships and new spiritual movements can often be traced to the denial, repression and return of our dark side. Transpersonal psychology offers a way of approaching, reframing and redeeming the unconscious depths of our psyche, with its metaphors of shadows and daimons on the one hand, and its therapeutic practices for symbolically containing and transcending polarities on the other. In its absence, any spirituality which eulogises holistic growth is likely to engender the reverse effect.

  17. Can invertebrates see the e-vector of polarization as a separate modality of light?

    Science.gov (United States)

    Labhart, Thomas

    2016-12-15

    The visual world is rich in linearly polarized light stimuli, which are hidden from the human eye. But many invertebrate species make use of polarized light as a source of valuable visual information. However, exploiting light polarization does not necessarily imply that the electric (e)-vector orientation of polarized light can be perceived as a separate modality of light. In this Review, I address the question of whether invertebrates can detect specific e-vector orientations in a manner similar to that of humans perceiving spectral stimuli as specific hues. To analyze e-vector orientation, the signals of at least three polarization-sensitive sensors (analyzer channels) with different e-vector tuning axes must be compared. The object-based, imaging polarization vision systems of cephalopods and crustaceans, as well as the water-surface detectors of flying backswimmers, use just two analyzer channels. Although this excludes the perception of specific e-vector orientations, a two-channel system does provide a coarse, categoric analysis of polarized light stimuli, comparable to the limited color sense of dichromatic, 'color-blind' humans. The celestial compass of insects employs three or more analyzer channels. However, that compass is multimodal, i.e. e-vector information merges with directional information from other celestial cues, such as the solar azimuth and the spectral gradient in the sky, masking e-vector information. It seems that invertebrate organisms take no interest in the polarization details of visual stimuli, but polarization vision grants more practical benefits, such as improved object detection and visual communication for cephalopods and crustaceans, compass readings to traveling insects, or the alert 'water below!' to water-seeking bugs. © 2016. Published by The Company of Biologists Ltd.

  18. The human dorsal action control system develops in the absence of vision.

    Science.gov (United States)

    Fiehler, Katja; Burke, Michael; Bien, Siegfried; Röder, Brigitte; Rösler, Frank

    2009-01-01

    The primate dorsal pathway has been proposed to compute vision for action. Although recent findings suggest that dorsal pathway structures contribute to somatosensory action control as well, it is yet not clear whether or not the development of dorsal pathway functions depends on early visual experience. Using functional magnetic resonance imaging, we investigated the pattern of cortical activation in congenitally blind and matched blindfolded sighted adults while performing kinesthetically guided hand movements. Congenitally blind adults activated similar dorsal pathway structures as sighted controls. Group-specific activations were found in the extrastriate cortex and the auditory cortex for congenitally blind humans and in the precuneus and the presupplementary motor area for sighted humans. Dorsal pathway activity was in addition observed for working memory maintenance of kinesthetic movement information in both groups. Thus, the results suggest that dorsal pathway functions develop in the absence of vision. This favors the idea of a general mechanism of movement control that operates regardless of the sensory input modality. Group differences in cortical activation patterns imply different movement control strategies as a function of visual experience.

  19. Critical decisions on Cosmic Vision

    Science.gov (United States)

    2003-11-01

    Eddington had two aims, both remarkable and very pertinent to front-line astronomical interests. The first was to look for Earth-like planets outside our solar system - one of the key goals in the search to understand how life came to be, how it is that we live where we do in the universe and whether there are other potential life-supporting environments 'out there'. At the same time it was going to follow the path that the ESA-NASA mission SOHO had taken with the Sun of using astroseismology to look 'inside' stars. In the longer term, the loss of this one mission will not stop ESA and the scientific community pursuing the grand quests to which it would have contributed. The loss of the BepiColombo lander is also hard to take scientifically. ESA, in conjunction with the Japanese space agency, JAXA, will still put two orbiters around Mercury but the ‘ground truth’ provided by the lander is a big loss. However, to land on a planet so near the Sun is no small matter and was a bridge too far in present circumstances, and this chance for Europe to be first has probably been lost. The origins of the problems were recognised at the ESA Council meeting held in June. Several sudden demands on finance occurred in the spring, the most obvious and public being the unforeseen Ariane 5 grounding in January, delaying the launches of Rosetta and Smart-1. A temporary loan of EUR 100 million was granted, but must be paid back out of present resources by the end of 2006. ESA's SPC was therefore caught in a vice. Immediate mission starts had to be severely limited and the overall envelope of the programme contained. With this week’s decisions, the SPC has brought the scope of the Cosmic Vision programme down to a level that necessarily reflects the financial conditions rather than the ambitions of the scientific community. A long and painful discussion during the SPC meeting resulted in the conclusion that only one new mission can be started at this time, namely LISA Pathfinder

  20. Wnt signaling and polarity in freshwater sponges.

    Science.gov (United States)

    Windsor Reid, Pamela J; Matveev, Eugueni; McClymont, Alexandra; Posfai, Dora; Hill, April L; Leys, Sally P

    2018-02-02

    The Wnt signaling pathway is uniquely metazoan and used in many processes during development, including the formation of polarity and body axes. In sponges, one of the earliest diverging animal groups, Wnt pathway genes have diverse expression patterns in different groups including along the anterior-posterior axis of two sponge larvae, and in the osculum and ostia of others. We studied the function of Wnt signaling and body polarity formation through expression, knockdown, and larval manipulation in several freshwater sponge species. Sponge Wnts fall into sponge-specific and sponge-class specific subfamilies of Wnt proteins. Notably Wnt genes were not found in transcriptomes of the glass sponge Aphrocallistes vastus. Wnt and its signaling genes were expressed in archaeocytes of the mesohyl throughout developing freshwater sponges. Osculum formation was enhanced by GSK3 knockdown, and Wnt antagonists inhibited both osculum development and regeneration. Using dye tracking we found that the posterior poles of freshwater sponge larvae give rise to tissue that will form the osculum following metamorphosis. Together the data indicate that while components of canonical Wnt signaling may be used in development and maintenance of osculum tissue, it is likely that Wnt signaling itself occurs between individual cells rather than whole tissues or structures in freshwater sponges.

  1. Vision in high-level football officials

    Science.gov (United States)

    Serra, Pedro M.; McAlinden, Colm; Barrett, Brendan T.

    2017-01-01

    Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of pfootball officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual

  2. Vision in high-level football officials.

    Science.gov (United States)

    Baptista, António Manuel Gonçalves; Serra, Pedro M; McAlinden, Colm; Barrett, Brendan T

    2017-01-01

    Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of pfootball officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual

  3. Evaluation of a Portable Artificial Vision Device Among Patients With Low Vision.

    Science.gov (United States)

    Moisseiev, Elad; Mannis, Mark J

    2016-07-01

    Low vision is irreversible in many patients and constitutes a disability. When no treatment to improve vision is available, technological developments aid these patients in their daily lives. To evaluate the usefulness of a portable artificial vision device (OrCam) for patients with low vision. A prospective pilot study was conducted between July 1 and September 30, 2015, in a US ophthalmology department among 12 patients with visual impairment and best-corrected visual acuity of 20/200 or worse in their better eye. A 10-item test simulating activities of daily living was used to evaluate patients' functionality in 3 scenarios: using their best-corrected visual acuity with no low-vision aids, using low-vision aids if available, and using the portable artificial vision device. This 10-item test was devised for this study and is nonvalidated. The portable artificial vision device was tested at the patients' first visit and after 1 week of use at home. Scores on the 10-item daily function test. Among the 12 patients, scores on the 10-item test improved from a mean (SD) of 2.5 (1.6) using best-corrected visual acuity to 9.5 (0.5) using the portable artificial vision device at the first visit (mean difference, 7.0; 95% CI, 6.0-8.0; P artificial vision device were also better in the 7 patients who used other low-vision aids (9.7 [0.5] vs 6.0 [2.6], respectively; mean difference, 3.7; 95% CI, 1.5-5.9; P = .01). When patients used a portable artificial vision device, an increase in scores on a nonvalidated 10-item test of activities of daily living was seen. Further evaluations are warranted to determine the usefulness of this device among individuals with low vision.

  4. Vision in the deep sea.

    Science.gov (United States)

    Warrant, Eric J; Locket, N Adam

    2004-08-01

    detection and localisation of point-source bioluminescence at ecologically meaningful distances. At all depths, the eyes of animals active on and over the nutrient-rich sea floor are generally larger than the eyes of pelagic species. In fishes, the retinal ganglion cells are also frequently arranged in a horizontal visual streak, an adaptation for viewing the wide flat horizon of the sea floor, and all animals living there. These and many other aspects of light and vision in the deep sea are reviewed in support of the following conclusion: it is not only the intensity of light at different depths, but also its distribution in space, which has been a major force in the evolution of deep-sea vision.

  5. Clinical Tests of Ultra-Low Vision Used to Evaluate Rudimentary Visual Perceptions Enabled by the BrainPort Vision Device.

    Science.gov (United States)

    Nau, Amy; Bach, Michael; Fisher, Christopher

    2013-01-01

    We evaluated whether existing ultra-low vision tests are suitable for measuring outcomes using sensory substitution. The BrainPort is a vision assist device coupling a live video feed with an electrotactile tongue display, allowing a user to gain information about their surroundings. We enrolled 30 adult subjects (age range 22-74) divided into two groups. Our blind group included 24 subjects ( n = 16 males and n = 8 females, average age 50) with light perception or worse vision. Our control group consisted of six subjects ( n = 3 males, n = 3 females, average age 43) with healthy ocular status. All subjects performed 11 computer-based psychophysical tests from three programs: Basic Assessment of Light Motion, Basic Assessment of Grating Acuity, and the Freiburg Vision Test as well as a modified Tangent Screen. Assessments were performed at baseline and again using the BrainPort after 15 hours of training. Most tests could be used with the BrainPort. Mean success scores increased for all of our tests except contrast sensitivity. Increases were statistically significant for tests of light perception (8.27 ± 3.95 SE), time resolution (61.4% ± 3.14 SE), light localization (44.57% ± 3.58 SE), grating orientation (70.27% ± 4.64 SE), and white Tumbling E on a black background (2.49 logMAR ± 0.39 SE). Motion tests were limited by BrainPort resolution. Tactile-based sensory substitution devices are amenable to psychophysical assessments of vision, even though traditional visual pathways are circumvented. This study is one of many that will need to be undertaken to achieve a common outcomes infrastructure for the field of artificial vision.

  6. Machine vision for real time orbital operations

    Science.gov (United States)

    Vinz, Frank L.

    1988-01-01

    Machine vision for automation and robotic operation of Space Station era systems has the potential for increasing the efficiency of orbital servicing, repair, assembly and docking tasks. A machine vision research project is described in which a TV camera is used for inputing visual data to a computer so that image processing may be achieved for real time control of these orbital operations. A technique has resulted from this research which reduces computer memory requirements and greatly increases typical computational speed such that it has the potential for development into a real time orbital machine vision system. This technique is called AI BOSS (Analysis of Images by Box Scan and Syntax).

  7. Computer vision based room interior design

    Science.gov (United States)

    Ahmad, Nasir; Hussain, Saddam; Ahmad, Kashif; Conci, Nicola

    2015-12-01

    This paper introduces a new application of computer vision. To the best of the author's knowledge, it is the first attempt to incorporate computer vision techniques into room interior designing. The computer vision based interior designing is achieved in two steps: object identification and color assignment. The image segmentation approach is used for the identification of the objects in the room and different color schemes are used for color assignment to these objects. The proposed approach is applied to simple as well as complex images from online sources. The proposed approach not only accelerated the process of interior designing but also made it very efficient by giving multiple alternatives.

  8. Stereo vision with distance and gradient recognition

    Science.gov (United States)

    Kim, Soo-Hyun; Kang, Suk-Bum; Yang, Tae-Kyu

    2007-12-01

    Robot vision technology is needed for the stable walking, object recognition and the movement to the target spot. By some sensors which use infrared rays and ultrasonic, robot can overcome the urgent state or dangerous time. But stereo vision of three dimensional space would make robot have powerful artificial intelligence. In this paper we consider about the stereo vision for stable and correct movement of a biped robot. When a robot confront with an inclination plane or steps, particular algorithms are needed to go on without failure. This study developed the recognition algorithm of distance and gradient of environment by stereo matching process.

  9. Vision Issues and Space Flight: Evaluation of One-Carbon Metabolism Polymorphisms

    Science.gov (United States)

    Smith, Scott M.; Gregory, Jesse F.; Zeisel, Steven; Ueland, Per; Gibson, C. R.; Mader, Thomas; Kinchen, Jason; Ploutz-Snyder, Robert; Zwart, Sara R.

    2015-01-01

    Intermediates of the one-carbon metabolic pathway are altered in astronauts who experience vision-related issues during and after space flight. Serum concentrations of homocysteine, cystathionine, 2-methylcitric acid, and methylmalonic acid were higher in astronauts with ophthalmic changes than in those without (Zwart et al., J Nutr, 2012). These differences existed before, during, and after flight. Potential confounding factors did not explain the differences. Genetic polymorphisms could contribute to these differences, and could help explain why crewmembers on the same mission do not all have ophthalmic issues, despite the same environmental factors (e.g., microgravity, exercise, diet). A follow-up study was conducted to evaluate 5 polymorphisms of enzymes in the one-carbon pathway, and to evaluate how these relate to vision and other ophthalmic changes after flight. Preliminary evaluations of the genetic data indicate that all of the crewmembers with the MTRR GG genotype had vision issues to one degree or another. However, not everyone who had vision issues had this genetic polymorphism, so the situation is more complex than the involvement of this single polymorphism. Metabolomic and further data analyses are underway to clarify these findings, but the preliminary assessments are promising.

  10. Anatomical Reconstruction and Functional Imaging Reveal an Ordered Array of Skylight Polarization Detectors in Drosophila.

    Science.gov (United States)

    Weir, Peter T; Henze, Miriam J; Bleul, Christiane; Baumann-Klausener, Franziska; Labhart, Thomas; Dickinson, Michael H

    2016-05-11

    Many insects exploit skylight polarization as a compass cue for orientation and navigation. In the fruit fly, Drosophila melanogaster, photoreceptors R7 and R8 in the dorsal rim area (DRA) of the compound eye are specialized to detect the electric vector (e-vector) of linearly polarized light. These photoreceptors are arranged in stacked pairs with identical fields of view and spectral sensitivities, but mutually orthogonal microvillar orientations. As in larger flies, we found that the microvillar orientation of the distal photoreceptor R7 changes in a fan-like fashion along the DRA. This anatomical arrangement suggests that the DRA constitutes a detector for skylight polarization, in which different e-vectors maximally excite different positions in the array. To test our hypothesis, we measured responses to polarized light of varying e-vector angles in the terminals of R7/8 cells using genetically encoded calcium indicators. Our data confirm a progression of preferred e-vector angles from anterior to posterior in the DRA, and a strict orthogonality between the e-vector preferences of paired R7/8 cells. We observed decreased activity in photoreceptors in response to flashes of light polarized orthogonally to their preferred e-vector angle, suggesting reciprocal inhibition between photoreceptors in the same medullar column, which may serve to increase polarization contrast. Together, our results indicate that the polarization-vision system relies on a spatial map of preferred e-vector angles at the earliest stage of sensory processing. The fly's visual system is an influential model system for studying neural computation, and much is known about its anatomy, physiology, and development. The circuits underlying motion processing have received the most attention, but researchers are increasingly investigating other functions, such as color perception and object recognition. In this work, we investigate the early neural processing of a somewhat exotic sense, called

  11. Circularly polarized antennas

    CERN Document Server

    Gao, Steven; Zhu, Fuguo

    2013-01-01

    This book presents a comprehensive insight into the design techniques for different types of CP antenna elements and arrays In this book, the authors address a broad range of topics on circularly polarized (CP) antennas. Firstly, it introduces to the reader basic principles, design techniques and characteristics of various types of CP antennas, such as CP patch antennas, CP helix antennas, quadrifilar helix antennas (QHA), printed quadrifilar helix antennas (PQHA), spiral antenna, CP slot antennas, CP dielectric resonator antennas, loop antennas, crossed dipoles, monopoles and CP horns. Adva

  12. Plasma polarization spectroscopy

    CERN Document Server

    Iwamae, Atsushi

    2008-01-01

    Plasma Polarization Spectroscopy (PPS) is now becoming a standard diagnostic technique for working with laboratory plasmas. This new area needs a comprehensive framework, both experimental and theoretical. This book reviews the historical development of PPS, develops a general theoretical formulation to deal with this phenomenon, along with an overview of relevant cross sections, and reports on laboratory experiments so far performed. It also includes various facets that are interesting from this standpoint, e.g. X-ray lasers and effects of microwave irradiation. It also offers a timely discussion of instrumentation that is quite important in a practical PPS experiment.

  13. System for measuring the proton polarization in a polarized target

    International Nuclear Information System (INIS)

    Karnaukhov, I.M.; Lukhanin, A.A.; Telegin, Yu.N.; Trotsenko, V.I.; Chechetenko, V.F.

    1984-01-01

    The system for measuring the proton polarization in a polarized target representing the high-sensitivity nuclear magnetic resonance (NMR) is described Q-meter with series connection and a circuit for measuring system resonance characteristic is used for NMR-absorption signal recording. Measuring coil is produced of a strip conductor in order to obtain uniform system sensitivity to polarization state in all target volume and improve signal-to-noise ratio. Polarization measuring system operates ion-line with the M-6000 computer. The total measuring error for the value of free proton polarization in target taking into account the error caused by local depolarization of working substance under irradiation by high-intense photon beam is <= 6%. Long-term application of the described system for measuring the proton polarization in the LUEh-20000 accelerator target used in the pion photoproduction experiments has demonstrated its high reliability

  14. Machine vision based teleoperation aid

    Science.gov (United States)

    Hoff, William A.; Gatrell, Lance B.; Spofford, John R.

    1991-01-01

    When teleoperating a robot using video from a remote camera, it is difficult for the operator to gauge depth and orientation from a single view. In addition, there are situations where a camera mounted for viewing by the teleoperator during a teleoperation task may not be able to see the tool tip, or the viewing angle may not be intuitive (requiring extensive training to reduce the risk of incorrect or dangerous moves by the teleoperator). A machine vision based teleoperator aid is presented which uses the operator's camera view to compute an object's pose (position and orientation), and then overlays onto the operator's screen information on the object's current and desired positions. The operator can choose to display orientation and translation information as graphics and/or text. This aid provides easily assimilated depth and relative orientation information to the teleoperator. The camera may be mounted at any known orientation relative to the tool tip. A preliminary experiment with human operators was conducted and showed that task accuracies were significantly greater with than without this aid.

  15. Machine vision and the OMV

    Science.gov (United States)

    Mcanulty, M. A.

    1986-01-01

    The orbital Maneuvering Vehicle (OMV) is intended to close with orbiting targets for relocation or servicing. It will be controlled via video signals and thruster activation based upon Earth or space station directives. A human operator is squarely in the middle of the control loop for close work. Without directly addressing future, more autonomous versions of a remote servicer, several techniques that will doubtless be important in a future increase of autonomy also have some direct application to the current situation, particularly in the area of image enhancement and predictive analysis. Several techniques are presentet, and some few have been implemented, which support a machine vision capability proposed to be adequate for detection, recognition, and tracking. Once feasibly implemented, they must then be further modified to operate together in real time. This may be achieved by two courses, the use of an array processor and some initial steps toward data reduction. The methodology or adapting to a vector architecture is discussed in preliminary form, and a highly tentative rationale for data reduction at the front end is also discussed. As a by-product, a working implementation of the most advanced graphic display technique, ray-casting, is described.

  16. Evolutionary analysis of vision genes identifies potential drivers of visual differences between giraffe and okapi

    Directory of Open Access Journals (Sweden)

    Edson Ishengoma

    2017-04-01

    Full Text Available Background The capacity of visually oriented species to perceive and respond to visual signal is integral to their evolutionary success. Giraffes are closely related to okapi, but the two species have broad range of phenotypic differences including their visual capacities. Vision studies rank giraffe’s visual acuity higher than all other artiodactyls despite sharing similar vision ecological determinants with many of them. The extent to which the giraffe’s unique visual capacity and its difference with okapi is reflected by changes in their vision genes is not understood. Methods The recent availability of giraffe and okapi genomes provided opportunity to identify giraffe and okapi vision genes. Multiple strategies were employed to identify thirty-six candidate mammalian vision genes in giraffe and okapi genomes. Quantification of selection pressure was performed by a combination of branch-site tests of positive selection and clade models of selection divergence through comparing giraffe and okapi vision genes and orthologous sequences from other mammals. Results Signatures of selection were identified in key genes that could potentially underlie giraffe and okapi visual adaptations. Importantly, some genes that contribute to optical transparency of the eye and those that are critical in light signaling pathway were found to show signatures of adaptive evolution or selection divergence. Comparison between giraffe and other ruminants identifies significant selection divergence in CRYAA and OPN1LW. Significant selection divergence was identified in SAG while positive selection was detected in LUM when okapi is compared with ruminants and other mammals. Sequence analysis of OPN1LW showed that at least one of the sites known to affect spectral sensitivity of the red pigment is uniquely divergent between giraffe and other ruminants. Discussion By taking a systemic approach to gene function in vision, the results provide the first molecular clues

  17. Evolutionary analysis of vision genes identifies potential drivers of visual differences between giraffe and okapi.

    Science.gov (United States)

    Ishengoma, Edson; Agaba, Morris; Cavener, Douglas R

    2017-01-01

    The capacity of visually oriented species to perceive and respond to visual signal is integral to their evolutionary success. Giraffes are closely related to okapi, but the two species have broad range of phenotypic differences including their visual capacities. Vision studies rank giraffe's visual acuity higher than all other artiodactyls despite sharing similar vision ecological determinants with many of them. The extent to which the giraffe's unique visual capacity and its difference with okapi is reflected by changes in their vision genes is not understood. The recent availability of giraffe and okapi genomes provided opportunity to identify giraffe and okapi vision genes. Multiple strategies were employed to identify thirty-six candidate mammalian vision genes in giraffe and okapi genomes. Quantification of selection pressure was performed by a combination of branch-site tests of positive selection and clade models of selection divergence through comparing giraffe and okapi vision genes and orthologous sequences from other mammals. Signatures of selection were identified in key genes that could potentially underlie giraffe and okapi visual adaptations. Importantly, some genes that contribute to optical transparency of the eye and those that are critical in light signaling pathway were found to show signatures of adaptive evolution or selection divergence. Comparison between giraffe and other ruminants identifies significant selection divergence in CRYAA and OPN1LW . Significant selection divergence was identified in SAG while positive selection was detected in LUM when okapi is compared with ruminants and other mammals. Sequence analysis of OPN1LW showed that at least one of the sites known to affect spectral sensitivity of the red pigment is uniquely divergent between giraffe and other ruminants. By taking a systemic approach to gene function in vision, the results provide the first molecular clues associated with giraffe and okapi vision adaptations. At

  18. Future Vision for Instrumentation, Information, and Control Modernization

    International Nuclear Information System (INIS)

    Thomas, Ken D.

    2012-01-01

    A Future Vision of a transformed nuclear plant operating model based on an integrated digital environment has been developed as part of the Advanced Instrumentation, Information, and Control (II and C) research pathway, under the Light Water Reactor (LWR) Sustainability Program. This is a research and development program sponsored by the U.S. Department of Energy (DOE), performed in close collaboration with the nuclear utility industry, to provide the technical foundations for licensing and managing the long-term, safe and economical operation of current nuclear power plants. II and C has been identified as a potential life-limiting issue for the domestic LWR fleet in addressing the reliability and aging concerns of the legacy systems in service today. The Future Vision is based on a digital architecture that encompasses all aspects of plant operations and support, integrating plant systems, plant work processes, and plant workers in a seamless digital environment to enhance nuclear safety, increase productivity, and improve overall plant performance. Pilot projects are being conducted as the means for industry to gain confidence in these new technologies for use in nuclear plant work activities. The pilot projects introduce new digital technologies into the nuclear plant operating environment at host operating plants to demonstrate and validate them for production usage. In turn, the pilot project technologies serve as the stepping stones to the eventual seamless digital environment as described in the Future Vision. Initial project results confirm that the technologies can provide substantial efficiency and human performance benefits while resolving the reliability and aging concerns of the legacy systems. (author)

  19. Macrophage Polarization in Metabolism and Metabolic Disease

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2013-08-01

    Full Text Available BACKGROUND: Obesity is now recognized as the main cause of the worldwide epidemic of type 2 diabetes. Obesity-associated chronic inflammation is a contributing key factor for type 2 diabetes and cardiovascular disease. Numbers of studies have clearly demonstrated that the immune system and metabolism are highly integrated. CONTENT: Macrophages are an essential component of innate immunity and play a central role in inflammation and host defense. Moreover, these cells have homeostatic functions beyond defense, including tissue remodeling in ontogenesis and orchestration of metabolic functions. Diversity and plasticity are hallmarks of cells of the monocyte-macrophage lineage. In response to interferons (IFNs, toll-like receptor (TLR, or interleukin (IL-4/IL-13 signals, macrophages undergo M1 (classical or M2 (alternative activation. Progress has now been made in defining the signaling pathways, transcriptional networks, and epigenetic mechanisms underlying M1, M2 or M2-like polarized activation. SUMMARY: In response to various signals, macrophages may undergo classical M1 activation (stimulated by TLR ligands and IFN-γ or alternative M2 activation (stimulated by IL-4/IL-13; these states mirror the T helper (Th1–Th2 polarization of T cells. Pathology is frequently associated with dynamic changes in macrophage activation, with classically activated M1 cells implicate in initiating and sustaining inflammation, meanwhile M2 or M2-like activated cells associated with resolution or smoldering chronic inflammation. Identification of the mechanisms and molecules that are associated with macrophage plasticity and polarized activation provides a basis for macrophage centered diagnostic and therapeutic strategies. KEYWORDS: obesity, adipose tissue, inflammation, macrophage polarization.

  20. Effects of Vision Restoration Training on Early Visual Cortex in Patients With Cerebral Blindness Investigated With Functional Magnetic Resonance Imaging

    NARCIS (Netherlands)

    Raemaekers, M.; Bergsma, D.P.; van Wezel, Richard Jack Anton; van der Wildt, G.J.; van den Berg, A.V.

    Cerebral blindness is a loss of vision as a result of postchiasmatic damage to the visual pathways. Parts of the lost visual field can be restored through training. However, the neuronal mechanisms through which training effects occur are still unclear. We therefore assessed training-induced changes

  1. International Conference on Computational Vision and Robotics

    CERN Document Server

    2015-01-01

    Computer Vision and Robotic is one of the most challenging areas of 21st century. Its application ranges from Agriculture to Medicine, Household applications to Humanoid, Deep-sea-application to Space application, and Industry applications to Man-less-plant. Today’s technologies demand to produce intelligent machine, which are enabling applications in various domains and services. Robotics is one such area which encompasses number of technology in it and its application is widespread. Computational vision or Machine vision is one of the most challenging tools for the robot to make it intelligent.   This volume covers chapters from various areas of Computational Vision such as Image and Video Coding and Analysis, Image Watermarking, Noise Reduction and Cancellation, Block Matching and Motion Estimation, Tracking of Deformable Object using Steerable Pyramid Wavelet Transformation, Medical Image Fusion, CT and MRI Image Fusion based on Stationary Wavelet Transform. The book also covers articles from applicati...

  2. How Diabetics Lose Vision: Molecular and Biochemical ...

    African Journals Online (AJOL)

    Diabetic patients are at risk of increased morbidity and mortality from macrovascular and microvascular complications. The increased risk of the vascular complications includes genetic factors, hyperglycaemia, hypertension, hyperlipidaemiaand oxidative stress. The mechanisms by which hyperglycaemia causes vision loss ...

  3. Vision systems for scientific and engineering applications

    International Nuclear Information System (INIS)

    Chadda, V.K.

    2009-01-01

    Human performance can get degraded due to boredom, distraction and fatigue in vision-related tasks such as measurement, counting etc. Vision based techniques are increasingly being employed in many scientific and engineering applications. Notable advances in this field are emerging from continuing improvements in the fields of sensors and related technologies, and advances in computer hardware and software. Automation utilizing vision-based systems can perform repetitive tasks faster and more accurately, with greater consistency over time than humans. Electronics and Instrumentation Services Division has developed vision-based systems for several applications to perform tasks such as precision alignment, biometric access control, measurement, counting etc. This paper describes in brief four such applications. (author)

  4. Object categorization: computer and human vision perspectives

    National Research Council Canada - National Science Library

    Dickinson, Sven J

    2009-01-01

    .... The result of a series of four highly successful workshops on the topic, the book gathers many of the most distinguished researchers from both computer and human vision to reflect on their experience...

  5. Connected and autonomous vehicles 2040 vision.

    Science.gov (United States)

    2014-07-01

    The Pennsylvania Department of Transportation (PennDOT) commissioned a one-year project, Connected and Autonomous : Vehicles 2040 Vision, with researchers at Carnegie Mellon University (CMU) to assess the implications of connected and : autonomous ve...

  6. Vision Hampton Roads : public responsiveness summary.

    Science.gov (United States)

    2010-02-23

    All comments submitted to Vision Hampton Roads were reviewed prior to addition to the final : document. Using this Public Responsiveness Summary, citizens will be able to see and track how : their engagement has impacted results. On the following pag...

  7. Behavioral Risk Factors - Vision & Eye Health

    Data.gov (United States)

    U.S. Department of Health & Human Services — 2005-2015. In 2013 and subsequently, one question in the core of BRFSS asks about vision: Are you blind or do you have serious difficulty seeing, even when wearing...

  8. Behavioral Risk Factors - Vision & Eye Health

    Data.gov (United States)

    U.S. Department of Health & Human Services — 2005-2016. In 2013 and subsequently, one question in the core of BRFSS asks about vision: Are you blind or do you have serious difficulty seeing, even when wearing...

  9. Non-Proliferative Diabetic Retinopathy Vision Simulator

    Science.gov (United States)

    ... blood or fluid. The leaking fluid causes the retina to swell or to form deposits. Previous Proliferative Diabetic Retinopathy Vision Simulator Related Ask an Ophthalmologist Answers How common is retinal detachment for people with high myopia? Mar 29, 2017 ...

  10. A computer vision for animal ecology.

    Science.gov (United States)

    Weinstein, Ben G

    2017-11-07

    A central goal of animal ecology is to observe species in the natural world. The cost and challenge of data collection often limit the breadth and scope of ecological study. Ecologists often use image capture to bolster data collection in time and space. However, the ability to process these images remains a bottleneck. Computer vision can greatly increase the efficiency, repeatability and accuracy of image review. Computer vision uses image features, such as colour, shape and texture to infer image content. I provide a brief primer on ecological computer vision to outline its goals, tools and applications to animal ecology. I reviewed 187 existing applications of computer vision and divided articles into ecological description, counting and identity tasks. I discuss recommendations for enhancing the collaboration between ecologists and computer scientists and highlight areas for future growth of automated image analysis. © 2017 The Author. Journal of Animal Ecology © 2017 British Ecological Society.

  11. Physics Based Vision Systems for Robotic Manipulation

    Data.gov (United States)

    National Aeronautics and Space Administration — With the increase of robotic manipulation tasks (TA4.3), specifically dexterous manipulation tasks (TA4.3.2), more advanced computer vision algorithms will be...

  12. Robot vision for nuclear advanced robot

    International Nuclear Information System (INIS)

    Nakayama, Ryoichi; Okano, Hideharu; Kuno, Yoshinori; Miyazawa, Tatsuo; Shimada, Hideo; Okada, Satoshi; Kawamura, Astuo

    1991-01-01

    This paper describes Robot Vision and Operation System for Nuclear Advanced Robot. This Robot Vision consists of robot position detection, obstacle detection and object recognition. With these vision techniques, a mobile robot can make a path and move autonomously along the planned path. The authors implemented the above robot vision system on the 'Advanced Robot for Nuclear Power Plant' and tested in an environment mocked up as nuclear power plant facilities. Since the operation system for this robot consists of operator's console and a large stereo monitor, this system can be easily operated by one person. Experimental tests were made using the Advanced Robot (nuclear robot). Results indicate that the proposed operation system is very useful, and can be operate by only person. (author)

  13. Computer Vision Assisted Virtual Reality Calibration

    Science.gov (United States)

    Kim, W.

    1999-01-01

    A computer vision assisted semi-automatic virtual reality (VR) calibration technology has been developed that can accurately match a virtual environment of graphically simulated three-dimensional (3-D) models to the video images of the real task environment.

  14. Colombia, mining country. Vision a year 2019

    International Nuclear Information System (INIS)

    2006-01-01

    Scope of the state action for the mining sector, the performance of the mining sector, regional perceptions of mining development, construction of a long-term vision for the mining sector, the action plan and goals follow-up

  15. Polar drive on OMEGA

    Directory of Open Access Journals (Sweden)

    Radha P.B.

    2013-11-01

    Full Text Available High-convergence polar-drive experiments are being conducted on OMEGA [T. R. Boehly et al., Opt. Commum. 133, 495 (1997] using triple-picket laser pulses. The goal of OMEGA experiments is to validate modeling of oblique laser deposition, heat conduction in the presence of nonradial thermal gradients in the corona, and implosion energetics in the presence of laser–plasma interactions such as crossed-beam energy transfer. Simulated shock velocities near the equator, where the beams are obliquely incident, are within 5% of experimentally inferred values in warm plastic shells, well within the required accuracy for ignition. High, near-one-dimensional areal density is obtained in warm-plastic-shell implosions. Simulated backlit images of the compressing core are in good agreement with measured images. Outstanding questions that will be addressed in the future relate to the role of cross-beam transfer in polar drive irradiation and increasing the energy coupled into the target by decreasing beam obliquity.

  16. Mechanistic Framework for Establishment, Maintenance, and Alteration of Cell Polarity in Plants

    Directory of Open Access Journals (Sweden)

    Pankaj Dhonukshe

    2012-01-01

    Full Text Available Cell polarity establishment, maintenance, and alteration are central to the developmental and response programs of nearly all organisms and are often implicated in abnormalities ranging from patterning defects to cancer. By residing at the distinct plasma membrane domains polar cargoes mark the identities of those domains, and execute localized functions. Polar cargoes are recruited to the specialized membrane domains by directional secretion and/or directional endocytic recycling. In plants, auxin efflux carrier PIN proteins display polar localizations in various cell types and play major roles in directional cell-to-cell transport of signaling molecule auxin that is vital for plant patterning and response programs. Recent advanced microscopy studies applied to single cells in intact plants reveal subcellular PIN dynamics. They uncover the PIN polarity generation mechanism and identified important roles of AGC kinases for polar PIN localization. AGC kinase family members PINOID, WAG1, and WAG2, belonging to the AGC-3 subclass predominantly influence the polar localization of PINs. The emerging mechanism for AGC-3 kinases action suggests that kinases phosphorylate PINs mainly at the plasma membrane after initial symmetric PIN secretion for eventual PIN internalization and PIN sorting into distinct ARF-GEF-regulated polar recycling pathways. Thus phosphorylation status directs PIN translocation to different cell sides. Based on these findings a mechanistic framework evolves that suggests existence of cell side-specific recycling pathways in plants and implicates AGC3 kinases for differential PIN recruitment among them for eventual PIN polarity establishment, maintenance, and alteration.

  17. Effect of absence of vision on posture

    OpenAIRE

    Alotaibi, Abdullah Z.; Alghadir, Ahmad; Iqbal, Zaheen A.; Anwer, Shahnawaz

    2016-01-01

    [Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the ...

  18. COHERENT LASER VISION SYSTEM (CLVS) OPTION PHASE

    Energy Technology Data Exchange (ETDEWEB)

    Robert Clark

    1999-11-18

    The purpose of this research project was to develop a prototype fiber-optic based Coherent Laser Vision System (CLVS) suitable for DOE's EM Robotic program. The system provides three-dimensional (3D) vision for monitoring situations in which it is necessary to update the dimensional spatial data on the order of once per second. The system has total immunity to ambient lighting conditions.

  19. Office of the CIO: Setting the Vision

    Science.gov (United States)

    Rinaldi, James J.

    2006-01-01

    This slide presentation reviews the vision of the Office of JPL's Chief Information Officer for future of information technology (IT) at JPL. This includes a strong working relation with industry to provide cost efficient and effective IT services. This includes a vision of taking desktop to the next level and the process to achieve it and ensuring that JPL becomes a world class IT provider.

  20. Decreased Vision and Junctional Scotoma from Pituicytoma

    Directory of Open Access Journals (Sweden)

    Nancy Huynh

    2012-05-01

    Full Text Available Pituicytomas are rare neoplasms of the sellar region. We report a case of vision loss and a junctional scotoma in a 43-year-old woman caused by compression of the optic chiasm by a pituitary tumor. The morphological and immunohistochemical characteristics of the tumor were consistent with the diagnosis of pituicytoma. The tumor was debulked surgically, and the patient’s vision improved.

  1. COMPUTER VISION SYNDROME: A SHORT REVIEW.

    OpenAIRE

    Sameena; Mohd Inayatullah

    2012-01-01

    Computers are probably one of the biggest scientific inventions of the modern era, and since then they have become an integral part of our life. The increased usage of computers have lead to variety of ocular symptoms which includ es eye strain, tired eyes, irritation, redness, blurred vision, and diplopia, collectively referred to as Computer Vision Syndrome (CVS). CVS may have a significant impact not only on visual com fort but also occupational productivit...

  2. CRALBP supports the mammalian retinal visual cycle and cone vision.

    Science.gov (United States)

    Xue, Yunlu; Shen, Susan Q; Jui, Jonathan; Rupp, Alan C; Byrne, Leah C; Hattar, Samer; Flannery, John G; Corbo, Joseph C; Kefalov, Vladimir J

    2015-02-01

    Mutations in the cellular retinaldehyde-binding protein (CRALBP, encoded by RLBP1) can lead to severe cone photoreceptor-mediated vision loss in patients. It is not known how CRALBP supports cone function or how altered CRALBP leads to cone dysfunction. Here, we determined that deletion of Rlbp1 in mice impairs the retinal visual cycle. Mice lacking CRALBP exhibited M-opsin mislocalization, M-cone loss, and impaired cone-driven visual behavior and light responses. Additionally, M-cone dark adaptation was largely suppressed in CRALBP-deficient animals. While rearing CRALBP-deficient mice in the dark prevented the deterioration of cone function, it did not rescue cone dark adaptation. Adeno-associated virus-mediated restoration of CRALBP expression specifically in Müller cells, but not retinal pigment epithelial (RPE) cells, rescued the retinal visual cycle and M-cone sensitivity in knockout mice. Our results identify Müller cell CRALBP as a key component of the retinal visual cycle and demonstrate that this pathway is important for maintaining normal cone-driven vision and accelerating cone dark adaptation.

  3. Peripheral Vision of Youths with Low Vision: Motion Perception, Crowding, and Visual Search

    Science.gov (United States)

    Tadin, Duje; Nyquist, Jeffrey B.; Lusk, Kelly E.; Corn, Anne L.; Lappin, Joseph S.

    2012-01-01

    Purpose. Effects of low vision on peripheral visual function are poorly understood, especially in children whose visual skills are still developing. The aim of this study was to measure both central and peripheral visual functions in youths with typical and low vision. Of specific interest was the extent to which measures of foveal function predict performance of peripheral tasks. Methods. We assessed central and peripheral visual functions in youths with typical vision (n = 7, ages 10–17) and low vision (n = 24, ages 9–18). Experimental measures used both static and moving stimuli and included visual crowding, visual search, motion acuity, motion direction discrimination, and multitarget motion comparison. Results. In most tasks, visual function was impaired in youths with low vision. Substantial differences, however, were found both between participant groups and, importantly, across different tasks within participant groups. Foveal visual acuity was a modest predictor of peripheral form vision and motion sensitivity in either the central or peripheral field. Despite exhibiting normal motion discriminations in fovea, motion sensitivity of youths with low vision deteriorated in the periphery. This contrasted with typically sighted participants, who showed improved motion sensitivity with increasing eccentricity. Visual search was greatly impaired in youths with low vision. Conclusions. Our results reveal a complex pattern of visual deficits in peripheral vision and indicate a significant role of attentional mechanisms in observed impairments. These deficits were not adequately captured by measures of foveal function, arguing for the importance of independently assessing peripheral visual function. PMID:22836766

  4. Vision 2030. A Vision for the U.S. Concrete Industry

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2001-01-01

    On September 27, 2000, the concrete industry's Strategic Development Council hosted a Concrete Vision Workshop in Chicago, Illinois. Meeting participants included over 50 concrete, cement, and other allied industry chief executive officers, presidents, vice-presidents, laboratory and industry research managers, and government representatives. Participants discussed the state of the concrete industry 30 years ago, the state of the current industry, and their vision for the United States concrete industry in 2030. Moreover, they identified specific goals to achieve the industry's Vision 2030. This document, Vision 2030, is the product of that workshop and the comments received after a broad industry review.

  5. Polarized proton collider at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W. E-mail: mackay@bnl.govhttp://www.rhichome.bnl.gov/People/waldowaldo@bnl.gov; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N

    2003-03-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to {radical}s=500 GeV.

  6. Spin exchange in polarized deuterium

    International Nuclear Information System (INIS)

    Przewoski, B. von; Meyer, H.O.; Balewski, J.; Doskow, J.; Ibald, R.; Pollock, R.E.; Rinckel, T.; Wellinghausen, A.; Whitaker, T.J.; Daehnick, W.W.; Haeberli, W.; Schwartz, B.; Wise, T.; Lorentz, B.; Rathmann, F.; Pancella, P.V.; Saha, Swapan K.; Thoerngren-Engblom, P.

    2003-01-01

    We have measured the vector and tensor polarization of an atomic deuterium target as a function of the target density. The polarized deuterium was produced in an atomic beam source and injected into a storage cell. For this experiment, the atomic beam source was operated without rf transitions, in order to avoid complications from the unknown efficiency of these transitions. In this mode, the atomic beam is vector and tensor polarized and both polarizations can be measured simultaneously. We used a 1.2-cm-diam and 27-cm-long storage cell, which yielded an average target density between 3 and 9x10 11 at/cm 3 . We find that the tensor polarization decreases with increasing target density while the vector polarization remains constant. The data are in quantitative agreement with the calculated effect of spin exchange between deuterium atoms at low field

  7. Ultraviolet vision may be widespread in bats

    Science.gov (United States)

    Gorresen, P. Marcos; Cryan, Paul; Dalton, David C.; Wolf, Sandy; Bonaccorso, Frank

    2015-01-01

    Insectivorous bats are well known for their abilities to find and pursue flying insect prey at close range using echolocation, but they also rely heavily on vision. For example, at night bats use vision to orient across landscapes, avoid large obstacles, and locate roosts. Although lacking sharp visual acuity, the eyes of bats evolved to function at very low levels of illumination. Recent evidence based on genetics, immunohistochemistry, and laboratory behavioral trials indicated that many bats can see ultraviolet light (UV), at least at illumination levels similar to or brighter than those before twilight. Despite this growing evidence for potentially widespread UV vision in bats, the prevalence of UV vision among bats remains unknown and has not been studied outside of the laboratory. We used a Y-maze to test whether wild-caught bats could see reflected UV light and whether such UV vision functions at the dim lighting conditions typically experienced by night-flying bats. Seven insectivorous species of bats, representing five genera and three families, showed a statistically significant ‘escape-toward-the-light’ behavior when placed in the Y-maze. Our results provide compelling evidence of widespread dim-light UV vision in bats.

  8. Occupational psychophysics to establish vision requirements.

    Science.gov (United States)

    Johnson, Chris A

    2008-10-01

    To develop and implement a comprehensive procedure for determining vision requirements for different vocational and occupational tasks. Evaluations performed for more than 10 state agencies and businesses were conducted over a period of approximately 9 years. The procedure included a literature review, an assessment of potential visual functions to address, a formal job analysis, interviews with incumbent workers, obtaining advice and recommendations from subject matter experts (experienced incumbents and administrators), development of job-related simulation studies, linkage of simulation results to the job analysis, a review of appeals and critical incidents, a thorough assessment of work environments and conditions, and final recommendations. Examples of occupational simulations for quantitative job-related task performance for best-corrected visual acuity, uncorrected visual acuity, color vision, peripheral vision, the use of one vs. two eyes, naïve vs. experienced incumbents, and impoverished visual conditions are presented. Changes in task performance and confidence ratings were obtained for various levels of degraded vision. This procedure, referred to as "occupational psychophysics," provides a quantitative systematic method of defining the vision requirements for various essential job functions. In conjunction with the frequency of performance, requirements at entry to the job, safety, reasonable accommodation, alteration of the work environment, and administrative issues, this approach provides a quantitative, rational basis for establishing job-related vision requirements.

  9. Characteristics of the Nigerian low vision population | Barbie ...

    African Journals Online (AJOL)

    There are no studies available to describe the epidemiology and causes of low vision in Nigeria and Africa.Aretrospective record review was conducted of low vision patients seen at the 2-weeks-per-month low vision clinic carried out at ECWAEye hospital, Kano, by the Low VISION PROGRAMME between the periods 1999 ...

  10. Machine Vision Giving Eyes to Robots. Resources in Technology.

    Science.gov (United States)

    Technology Teacher, 1990

    1990-01-01

    This module introduces machine vision, which can be used for inspection, robot guidance and part sorting. The future for machine vision will include new technology and will bring vision systems closer to the ultimate vision processor, the human eye. Includes a student quiz, outcomes, and activities. (JOW)

  11. Linear polarization of BY Draconis

    International Nuclear Information System (INIS)

    Koch, R.H.; Pfeiffer, R.J.

    1976-01-01

    Linear polarization measurements are reported in four bandpasses for the flare star BY Dra. The red polarization is intrinsically variable at a confidence level greater than 99 percent. On a time scale of many months, the variability is not phase-locked to either a rotational or a Keplerian ephemeris. The observations of the three other bandpasses are useful principally to indicate a polarization spectrum rising toward shorter wavelengths

  12. Polarity in Mammalian Epithelial Morphogenesis

    OpenAIRE

    Roignot, Julie; Peng, Xiao; Mostov, Keith

    2013-01-01

    Cell polarity is fundamental for the architecture and function of epithelial tissues. Epithelial polarization requires the intervention of several fundamental cell processes, whose integration in space and time is only starting to be elucidated. To understand what governs the building of epithelial tissues during development, it is essential to consider the polarization process in the context of the whole tissue. To this end, the development of three-dimensional organotypic cell culture model...

  13. A polarized alkali ion source

    International Nuclear Information System (INIS)

    Boettger, R.; Tungate, G.; Bauer, B.; Egelhof, P.; Moebius, K.H.; Steffens, E.

    1978-01-01

    The beam foil technique has been applied to detect nuclear vector polarization of a 10 keV 23 Na + beam. The result was about 70% of the atomic beam polarization thus limiting the depolarization by the surface ionizer to at most 30%. In a Coulomb excitation experiment with a tensor polarized 42 MeV 23 Na 7+ beam an effect of 0.011 +- 0.003 was measured yielding a value of t 20 approx. 0.04 for the beam polarization. The depolarization during the acceleration process can be estimated to be about 0.8. (orig.) [de

  14. The SLAC polarized electron source

    International Nuclear Information System (INIS)

    Tang, H.; Alley, R.; Frisch, J.

    1995-06-01

    The SLAC polarized electron source employs a photocathode DC high voltage gun with a loadlock and a YAG pumped Ti:sapphire laser system for colliding beam experiments or a flash lamp pumped Ti:sapphire laser for fixed target experiments. It uses a thin, strained GaAs(100) photocathode, and is capable of producing a pulsed beam with a polarization of ≥80% and a peak current exceeding 10 A. Its operating efficiency has reached 99%. The physics and technology of producing high polarization electron beams from a GaAs photocathode will be reviewed. The prospects of realizing a polarized electron source for future linear colliders will also be discussed

  15. 75 FR 71146 - In the Matter of Certain Machine Vision Software, Machine Vision Systems, and Products Containing...

    Science.gov (United States)

    2010-11-22

    ... COMMISSION In the Matter of Certain Machine Vision Software, Machine Vision Systems, and Products Containing..., and the sale within the United States after importation of certain machine vision software, machine vision systems, or products containing same by reason of infringement of certain claims of U.S. Patent...

  16. 75 FR 60478 - In the Matter of Certain Machine Vision Software, Machine Vision Systems, and Products Containing...

    Science.gov (United States)

    2010-09-30

    ... COMMISSION In the Matter of Certain Machine Vision Software, Machine Vision Systems, and Products Containing... importation of certain machine vision software, machine vision systems, or products containing same by reason... Soft'') of Japan; Fuji Machine Manufacturing Co., Ltd. of Japan and Fuji America Corporation of Vernon...

  17. THE EFFECT OF VISION AND ROLE CLARITY ON TEAM PERFORMANCE

    OpenAIRE

    Lynn, Gary; Kalay, Faruk

    2015-01-01

    ABSTRACTAlthough many studies conclude that vision and role clarity are important at the organizational level, the impacts of vision and role clarity on innovation/teams have received far less attention. A strong vision and role definition can provide direction to a team and can positively impact its ability to succeed. The purpose of this research is to discuss vision components and Role Clarity, and explore their impacts on team performance. After studying the vision on a series of nine inn...

  18. Wind Vision: A New Era for Wind Power in the United States (Highlights); U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    This is a four-part Wind Vision project, consisting of Wind Vision Highlights, Executive Summary, a Full Report, and Appendix. The U.S. Department of Energy (DOE) Wind Program, in close cooperation with the wind industry, led a comprehensive analysis to evaluate future pathways for the wind industry. The Wind Vision report updates and expands upon the DOE's 2008 report, 20% Wind Energy by 2030, and defines the societal, environmental, and economic benefits of wind power in a scenario with wind energy supplying 10% of national end-use electricity demand by 2020, 20% by 2030, and 35% by 2050.

  19. Efficacy of vision therapy in children with learning disability and associated binocular vision anomalies

    Directory of Open Access Journals (Sweden)

    Jameel Rizwana Hussaindeen

    2018-01-01

    Conclusion: Children with specific learning disorders have a high frequency of binocular vision disorders and vision therapy plays a significant role in improving the BV parameters. Children with SLD should be screened for BV anomalies as it could potentially be an added hindrance to the reading difficulty in this special population.

  20. Beyond W3C: TruVision--Enhanced Online Learning for People Blind or Vision Impaired.

    Science.gov (United States)

    Bate, Frank; Oliver, Ron

    This paper describes the design and development of TruVision, an online learning environment designed to enable blind and vision impaired students to develop skills and expertise in elementary and advanced information processing strategies to enable them to seek full-time employment within industry in such positions as administrative assistants,…

  1. Robotic Variable Polarity Plasma Arc (VPPA) Welding

    Science.gov (United States)

    Jaffery, Waris S.

    1993-01-01

    The need for automated plasma welding was identified in the early stages of the Space Station Freedom Program (SSFP) because it requires approximately 1.3 miles of welding for assembly. As a result of the Variable Polarity Plasma Arc Welding (VPPAW) process's ability to make virtually defect-free welds in aluminum, it was chosen to fulfill the welding needs. Space Station Freedom will be constructed of 2219 aluminum utilizing the computer controlled VPPAW process. The 'Node Radial Docking Port', with it's saddle shaped weld path, has a constantly changing surface angle over 360 deg of the 282 inch weld. The automated robotic VPPAW process requires eight-axes of motion (six-axes of robot and two-axes of positioner movement). The robot control system is programmed to maintain Torch Center Point (TCP) orientation perpendicular to the part while the part positioner is tilted and rotated to maintain the vertical up orientation as required by the VPPAW process. The combined speed of the robot and the positioner are integrated to maintain a constant speed between the part and the torch. A laser-based vision sensor system has also been integrated to track the seam and map the surface of the profile during welding.

  2. Intersection Recognition and Guide-Path Selection for a Vision-Based AGV in a Bidirectional Flow Network

    Directory of Open Access Journals (Sweden)

    Wu Xing

    2014-03-01

    Full Text Available Vision recognition and RFID perception are used to develop a smart AGV travelling on fixed paths while retaining low-cost, simplicity and reliability. Visible landmarks can describe features of shapes and geometric dimensions of lines and intersections, and RFID tags can directly record global locations on pathways and the local topological relations of crossroads. A topological map is convenient for building and editing without the need for accurate poses when establishing a priori knowledge of a workplace. To obtain the flexibility of bidirectional movement along guide-paths, a camera placed in the centre of the AGV looks downward vertically at landmarks on the floor. A small visual field presents many difficulties for vision guidance, especially for real-time, correct and reliable recognition of multi-branch crossroads. First, the region projection and contour scanning methods are both used to extract the features of shapes. Then LDA is used to reduce the number of the features' dimensions. Third, a hierarchical SVM classifier is proposed to classify their multi-branch patterns once the features of the shapes are complete. Our experiments in landmark recognition and navigation show that low-cost vision systems are insusceptible to visual noises, image breakages and floor changes, and a vision-based AGV can locate itself precisely on its paths, recognize different crossroads intelligently by verifying the conformance of vision and RFID information, and select its next pathway efficiently in a bidirectional flow network.

  3. Polar Biomedical Research - An Assessment.

    Science.gov (United States)

    1982-10-01

    to grow more crops in subpolar Alaska. The severity of the polar conditions in Antarctica allow no practical method for providing volumes of plant food...for an expanded population. Any experiments in polar regions in food production involving geothermal heat, solar energy, hydroponics , or aquaculture

  4. Create a Polarized Light Show.

    Science.gov (United States)

    Conrad, William H.

    1992-01-01

    Presents a lesson that introduces students to polarized light using a problem-solving approach. After illustrating the concept using a slinky and poster board with a vertical slot, students solve the problem of creating a polarized light show using Polya's problem-solving methods. (MDH)

  5. Carbon nanotube fiber terahertz polarizer

    Energy Technology Data Exchange (ETDEWEB)

    Zubair, Ahmed [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Tsentalovich, Dmitri E.; Young, Colin C. [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Heimbeck, Martin S. [Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Everitt, Henry O. [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Pasquali, Matteo [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Department of Chemistry, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Kono, Junichiro, E-mail: kono@rice.edu [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2016-04-04

    Conventional, commercially available terahertz (THz) polarizers are made of uniformly and precisely spaced metallic wires. They are fragile and expensive, with performance characteristics highly reliant on wire diameters and spacings. Here, we report a simple and highly error-tolerant method for fabricating a freestanding THz polarizer with nearly ideal performance, reliant on the intrinsically one-dimensional character of conduction electrons in well-aligned carbon nanotubes (CNTs). The polarizer was constructed on a mechanical frame over which we manually wound acid-doped CNT fibers with ultrahigh electrical conductivity. We demonstrated that the polarizer has an extinction ratio of ∼−30 dB with a low insertion loss (<0.5 dB) throughout a frequency range of 0.2–1.1 THz. In addition, we used a THz ellipsometer to measure the Müller matrix of the CNT-fiber polarizer and found comparable attenuation to a commercial metallic wire-grid polarizer. Furthermore, based on the classical theory of light transmission through an array of metallic wires, we demonstrated the most striking difference between the CNT-fiber and metallic wire-grid polarizers: the latter fails to work in the zero-spacing limit, where it acts as a simple mirror, while the former continues to work as an excellent polarizer even in that limit due to the one-dimensional conductivity of individual CNTs.

  6. Polarization-preserving holey fibers

    DEFF Research Database (Denmark)

    Broeng, Jes; Mogilevtsev, Dmitri; Libori, Stig E. Barkou

    2001-01-01

    In this work we suggest and discuss a microstructure of air capillaries with elliptical cross-section in a tread of glass that gives opportunity for Creation of polarization-preserving fiber with very small beat length between the fundamental modes of different polarization...

  7. Polarized Scintillating Targets at Psi

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2001-02-01

    Scintillating polarized targets are now routinely available: blocks of 18×18×5 mm scintillating organic polymer, doped with TEMPO, polarized dynamically in a field of 2.5 T in a vertical 3He-4He dilution refrigerator. A 19 mm diameter plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat.

  8. UV Coatings, Polarization, and Coronagraphy

    Science.gov (United States)

    Bolcar, Matthew R.; Quijada, Manuel; West, Garrett; Balasubramanian, Bala; Krist, John; Martin, Stefan; Sabatke, Derek

    2016-01-01

    Presenation for the Large UltraViolet Optical Infrared (LUVOIR) and Habitable Exoplanet Imager (HabEx) Science and Technology Definition Teams (STDT) on technical considerations regarding ultraviolet coatings, polarization, and coronagraphy. The presentations review the state-of-the-art in ultraviolet coatings, how those coatings generate polarization aberrations, and recent study results from both the LUVOIR and HabEx teams.

  9. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  10. Passive Night Vision Sensor Comparison for Unmanned Ground Vehicle Stereo Vision Navigation

    Science.gov (United States)

    Owens, Ken; Matthies, Larry

    2000-01-01

    One goal of the "Demo III" unmanned ground vehicle program is to enable autonomous nighttime navigation at speeds of up to 10 m.p.h. To perform obstacle detection at night with stereo vision will require night vision cameras that produce adequate image quality for the driving speeds, vehicle dynamics, obstacle sizes, and scene conditions that will be encountered. This paper analyzes the suitability of four classes of night vision cameras (3-5 micrometer cooled FLIR, 8-12 micrometer cooled FLIR, 8-12 micrometer uncooled FLIR, and image intensifiers) for night stereo vision, using criteria based on stereo matching quality, image signal to noise ratio, motion blur and synchronization capability. We find that only cooled FLIRs will enable stereo vision performance that meets the goals of the Demo III program for nighttime autonomous mobility.

  11. Integrins and epithelial cell polarity.

    Science.gov (United States)

    Lee, Jessica L; Streuli, Charles H

    2014-08-01

    Cell polarity is characterised by differences in structure, composition and function between at least two poles of a cell. In epithelial cells, these spatial differences allow for the formation of defined apical and basal membranes. It has been increasingly recognised that cell-matrix interactions and integrins play an essential role in creating epithelial cell polarity, although key gaps in our knowledge remain. This Commentary will discuss the mounting evidence for the role of integrins in polarising epithelial cells. We build a model in which both inside-out signals to polarise basement membrane assembly at the basal surface, and outside-in signals to control microtubule apical-basal orientation and vesicular trafficking are required for establishing and maintaining the orientation of epithelial cell polarity. Finally, we discuss the relevance of the basal integrin polarity axis to cancer. This article is part of a Minifocus on Establishing polarity. © 2014. Published by The Company of Biologists Ltd.

  12. Hyperon polarization: An experimental overview

    International Nuclear Information System (INIS)

    Lach, J.

    1992-12-01

    The fact that inclusively produced hyperons are produced with significant polarization was first discovered at Fermilab about seventeen years ago. This and subsequent experiments showed that Λ degree were produced polarized while bar Λ degree had no polarization in the same kinematical region. This set the stage for many experiments which showed that most hyperons are produced polarized. Recent Fermilab experiments have showed that this phenomena is even more complex than previously thought and theoretical understanding is still lacking. Nevertheless polarized hyperon beams have been an extremely useful experimental tool in measuring hyperon magnetic moments and hyperon β-decay. Recently, hyperon radiative decays have been studied and magnetic moment precession of channeled particles in bent crystals has been observed

  13. A review of polarized ion sources

    International Nuclear Information System (INIS)

    Schmor, P.W.

    1995-06-01

    The two main types of polarized ion sources in use on accelerators today are the Atomic Beam Polarized Ion Source (ABIS) source and the Optically Pumped Polarized Ion Source (OPPIS). Both types can provide beams of nuclearly polarized light ions which are either positively or negatively charged. Heavy ion polarized ion sources for accelerators are being developed. (author). 35 refs., 1 tab

  14. Color vision and fatigue: an incidental finding.

    Science.gov (United States)

    Hovis, Jeffery K; Ramaswamy, Shankaran

    2007-11-01

    Because there is little information available as to how fatigue and color vision interact, we present some incidental findings on how a protanope and a color-normal perform on several color vision tests after 1 night of sleep deprivation. A series of clinically and occupationally based color vision tests were administered to a protanope and a color-normal subject after they had stayed awake all night and after a regular night's sleep. There was essentially no change in their performance on the clinical color vision tests; however, both did worse on the occupationally based color vision tests after 1 night of sleep deprivation. The color-normal made numerous errors in identifying colors displayed on a video display terminal, whereas the protanope had a large increase in errors on the CN Lantern Test. Both subjects passed these respective tests after a regular night's sleep. The primary reason for color-normal's poor performance on the video display terminal test was probably due to a decrement in his visuo-motor control rather than a loss in color discrimination. In contrast, the protanope's poor performance on the lantern test was probably due to the additive effects of the inherent limitations of his visual system and fatigue.

  15. Correction for near vision in pseudophakic patients

    Directory of Open Access Journals (Sweden)

    Dujić Mirjana

    2004-01-01

    Full Text Available Objective of the study was to show the mean values of correction for near vision and to discuss the presbyopic correction in pseudophakic patients. Setting was the Eye department where authors work. Inclusion criteria for 55 patients were native or corrected distant vision of 0.8-1.0 on Snellen's chart; 0,6 on Jagger's chart for near vision; round pupil and good position of the implant. Biometry of the anterior chamber depth with Alcon biophysics during distant and near vision was performed in our study. „Hi square" test was carried out and it was concluded that patients younger than 59 years (41 eyes had median correction of +2.0 dsph, while patients older than 60 years (36 eyes had correction of+3.0 dsph, but it was not statistically significant. There was no statistically significant difference of the correction between pseudophakic (41 and phakic (19 eyes in patients younger than 59 years. The anterior movement of the IOL was 0.18 mm in the younger group and 0.15 mm in the older group. With good IOL movement and new materials which could have changeable refractive power, the problem of pseudophakic correction for near vision might be solved.

  16. Vision requirements for driver's license examiners.

    Science.gov (United States)

    Johnson, Chris A

    2005-08-01

    The purpose of this study was to determine the vision requirements for licensing and registration examiners (LREs) of motor vehicle drivers in the state of California. A comprehensive investigation was conducted that included a literature review, consideration of the Americans with Disabilities Act, analysis of materials with a subject matter expert panel, an overview of visual function tests, a formal job analysis, job audits and site visits to licensing offices, analysis of accidents and critical incidents, performance of simulation studies, and a review and evaluation of all materials collected during the study. Based on this analysis, three visual functions (best-corrected visual acuity, peripheral visual field extent, and color vision) were determined to be important for performing the essential job functions of an LRE. It was recommended that LREs demonstrate a best-corrected visual acuity of at least 20/20 in each eye, a peripheral visual field of at least 100 degrees diameter of horizontal and vertical extent in each eye (with no evidence of scotomas or pathologic areas of nonseeing within the visual field), and color vision capabilities that permit a passing score on the Farnsworth Panel D-15 color vision test. The findings of this investigation provide a strong basis for specifying and justifying vision requirements for performing essential job functions for an LRE in the state of California.

  17. Smad4 regulates growth plate matrix production and chondrocyte polarity.

    Science.gov (United States)

    Whitaker, Amanda T; Berthet, Ellora; Cantu, Andrea; Laird, Diana J; Alliston, Tamara

    2017-03-15

    Smad4 is an intracellular effector of the TGFβ family that has been implicated in Myhre syndrome, a skeletal dysplasia characterized by short stature, brachydactyly and stiff joints. The TGFβ pathway also plays a critical role in the development, organization and proliferation of the growth plate, although the exact mechanisms remain unclear. Skeletal phenotypes in Myhre syndrome overlap with processes regulated by the TGFβ pathway, including organization and proliferation of the growth plate and polarity of the chondrocyte. We used in vitro and in vivo models of Smad4 deficiency in chondrocytes to test the hypothesis that deregulated TGFβ signaling leads to aberrant extracellular matrix production and loss of chondrocyte polarity. Specifically, we evaluated growth plate chondrocyte polarity in tibiae of Col2-Cre +/- ;Smad4 fl/fl mice and in chondrocyte pellet cultures. In vitro and in vivo , Smad4 deficiency decreased aggrecan expression and increased MMP13 expression. Smad4 deficiency disrupted the balance of cartilage matrix synthesis and degradation, even though the sequential expression of growth plate chondrocyte markers was intact. Chondrocytes in Smad4-deficient growth plates also showed evidence of polarity defects, with impaired proliferation and ability to undergo the characteristic changes in shape, size and orientation as they differentiated from resting to hypertrophic chondrocytes. Therefore, we show that Smad4 controls chondrocyte proliferation, orientation, and hypertrophy and is important in regulating the extracellular matrix composition of the growth plate. © 2017. Published by The Company of Biologists Ltd.

  18. Smad4 regulates growth plate matrix production and chondrocyte polarity

    Directory of Open Access Journals (Sweden)

    Amanda T. Whitaker

    2017-03-01

    Full Text Available Smad4 is an intracellular effector of the TGFβ family that has been implicated in Myhre syndrome, a skeletal dysplasia characterized by short stature, brachydactyly and stiff joints. The TGFβ pathway also plays a critical role in the development, organization and proliferation of the growth plate, although the exact mechanisms remain unclear. Skeletal phenotypes in Myhre syndrome overlap with processes regulated by the TGFβ pathway, including organization and proliferation of the growth plate and polarity of the chondrocyte. We used in vitro and in vivo models of Smad4 deficiency in chondrocytes to test the hypothesis that deregulated TGFβ signaling leads to aberrant extracellular matrix production and loss of chondrocyte polarity. Specifically, we evaluated growth plate chondrocyte polarity in tibiae of Col2-Cre+/−;Smad4fl/fl mice and in chondrocyte pellet cultures. In vitro and in vivo, Smad4 deficiency decreased aggrecan expression and increased MMP13 expression. Smad4 deficiency disrupted the balance of cartilage matrix synthesis and degradation, even though the sequential expression of growth plate chondrocyte markers was intact. Chondrocytes in Smad4-deficient growth plates also showed evidence of polarity defects, with impaired proliferation and ability to undergo the characteristic changes in shape, size and orientation as they differentiated from resting to hypertrophic chondrocytes. Therefore, we show that Smad4 controls chondrocyte proliferation, orientation, and hypertrophy and is important in regulating the extracellular matrix composition of the growth plate.

  19. POLARIZED LIGHT IN PHYSIOTHERAPY

    Directory of Open Access Journals (Sweden)

    L. D. Tondiy

    2015-12-01

    Full Text Available The data on polarized light (PS - a new promising treatment, rehabilitation and prevention, which took its deserved place among the known therapeutic physical factors and may even compete with laser radiation of low and LED therapy. It is reflected the significant contribution of domestic scientists in the study of aircraft action on the body, its introduction in the treatment, rehabilitation and prevention of grippe, ARI. These action's mechanisms of the aircraft on the electro-physiological processes in the body that have the leading role in the regulation of its life. The new moment in the study of aircraft on the body is the evidence of its positive impact on the mechanisms of self body - its different units: the disease's banning - a revitalization of the stress-protective, stress-limiting system antioxidial, detoxification and other protection systems, the formation by the body antiviral and antimicrobial specific substances (interferon and lysozyme, activation of the immune system, phagocytosis, protective functions of skin. The protective and mobilizing role of the second link is studied: which is triggered in case of occurrence of disease or preexisting diseases: PL mobilized processes of restitution, reparations, compensation, immunity and microcirculation. The authors studied the possibility of aircraft's using to enhance performance, reduce side effects of physical factors, which are often used in the treatment (electric methods, treatment by sound, fresh and mineral water, etc..

  20. Update of the Polar SWIFT model for polar stratospheric ozone loss (Polar SWIFT version 2)

    Science.gov (United States)

    Wohltmann, Ingo; Lehmann, Ralph; Rex, Markus

    2017-07-01

    The Polar SWIFT model is a fast scheme for calculating the chemistry of stratospheric ozone depletion in polar winter. It is intended for use in global climate models (GCMs) and Earth system models (ESMs) to enable the simulation of mutual interactions between the ozone layer and climate. To date, climate models often use prescribed ozone fields, since a full stratospheric chemistry scheme is computationally very expensive. Polar SWIFT is based on a set of coupled differential equations, which simulate the polar vortex-averaged mixing ratios of the key species involved in polar ozone depletion on a given vertical level. These species are O3, chemically active chlorine (ClOx), HCl, ClONO2 and HNO3. The only external input parameters that drive the model are the fraction of the polar vortex in sunlight and the fraction of the polar vortex below the temperatures necessary for the formation of polar stratospheric clouds. Here, we present an update of the Polar SWIFT model introducing several improvements over the original model formulation. In particular, the model is now trained on vortex-averaged reaction rates of the ATLAS Chemistry and Transport Model, which enables a detailed look at individual processes and an independent validation of the different parameterizations contained in the differential equations. The training of the original Polar SWIFT model was based on fitting complete model runs to satellite observations and did not allow for this. A revised formulation of the system of differential equations is developed, which closely fits vortex-averaged reaction rates from ATLAS that represent the main chemical processes influencing ozone. In addition, a parameterization for the HNO3 change by denitrification is included. The rates of change of the concentrations of the chemical species of the Polar SWIFT model are purely chemical rates of change in the new version, whereas in the original Polar SWIFT model, they included a transport effect caused by the

  1. VISION: Verifiable Fuel Cycle Simulation Model

    Energy Technology Data Exchange (ETDEWEB)

    Jacob J. Jacobson; Abdellatif M. Yacout; Gretchen E. Matthern; Steven J. Piet; David E. Shropshire

    2009-04-01

    The nuclear fuel cycle is a very complex system that includes considerable dynamic complexity as well as detail complexity. In the nuclear power realm, there are experts and considerable research and development in nuclear fuel development, separations technology, reactor physics and waste management. What is lacking is an overall understanding of the entire nuclear fuel cycle and how the deployment of new fuel cycle technologies affects the overall performance of the fuel cycle. The Advanced Fuel Cycle Initiative’s systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing and delays in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works and can transition as technologies are changed. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model and some examples of how to use VISION.

  2. Robot vision system for remote plutonium disposition

    International Nuclear Information System (INIS)

    Kriikku, E.

    2000-01-01

    Tons of weapons-usable plutonium has been declared surplus to the national security needs of the United States. The Plutonium Immobilization Program (PIP) is a US Department of Energy sponsored program to place excess plutonium in a stable form and make it unattractive for reuse. A vision system was developed as part of PIP robotic and remote systems development. This vision system provides visual feedback to a can-loading robot that places plutonium/ceramic pucks in stainless steel cans. Inexpensive grayscale CCD cameras were used in conjunction with an off-the-shelf video capture card and computer to build an effective two-camera vision system. Testing demonstrates the viability of this technology for use in the Plutonium Immobilization Project facility, which is scheduled to begin operations in 2008

  3. A computational model for dynamic vision

    Science.gov (United States)

    Moezzi, Saied; Weymouth, Terry E.

    1990-01-01

    This paper describes a novel computational model for dynamic vision which promises to be both powerful and robust. Furthermore the paradigm is ideal for an active vision system where camera vergence changes dynamically. Its basis is the retinotopically indexed object-centered encoding of the early visual information. Specifically, the relative distances of objects to a set of referents is encoded in image registered maps. To illustrate the efficacy of the method, it is applied to the problem of dynamic stereo vision. Integration of depth information over multiple frames obtained by a moving robot generally requires precise information about the relative camera position from frame to frame. Usually, this information can only be approximated. The method facilitates the integration of depth information without direct use or knowledge of camera motion.

  4. A compact PE memory for vision chips

    Science.gov (United States)

    Cong, Shi; Zhe, Chen; Jie, Yang; Nanjian, Wu; Zhihua, Wang

    2014-09-01

    This paper presents a novel compact memory in the processing element (PE) for single-instruction multiple-data (SIMD) vision chips. The PE memory is constructed with 8 × 8 register cells, where one latch in the slave stage is shared by eight latches in the master stage. The memory supports simultaneous read and write on the same address in one clock cycle. Its compact area of 14.33 μm2/bit promises a higher integration level of the processor. A prototype chip with a 64 × 64 PE array is fabricated in a UMC 0.18 μm CMOS technology. Five types of the PE memory cell structure are designed and compared. The testing results demonstrate that the proposed PE memory architecture well satisfies the requirement of the vision chip in high-speed real-time vision applications, such as 1000 fps edge extraction.

  5. A compact PE memory for vision chips

    International Nuclear Information System (INIS)

    Shi Cong; Chen Zhe; Yang Jie; Wu Nanjian; Wang Zhihua

    2014-01-01

    This paper presents a novel compact memory in the processing element (PE) for single-instruction multiple-data (SIMD) vision chips. The PE memory is constructed with 8 × 8 register cells, where one latch in the slave stage is shared by eight latches in the master stage. The memory supports simultaneous read and write on the same address in one clock cycle. Its compact area of 14.33 μm 2 /bit promises a higher integration level of the processor. A prototype chip with a 64 × 64 PE array is fabricated in a UMC 0.18 μm CMOS technology. Five types of the PE memory cell structure are designed and compared. The testing results demonstrate that the proposed PE memory architecture well satisfies the requirement of the vision chip in high-speed real-time vision applications, such as 1000 fps edge extraction. (semiconductor integrated circuits)

  6. Visions 2025 and Linkage to NEXT

    Science.gov (United States)

    Wiscombe, W.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    This talk will describe the progress to date on creating a science-driven vision for the NASA Earth Science Enterprise (ESE) in the post-2010 period. This effort began in the Fall of 2001 by organizing five science workgroups with representatives from NASA, academia and other agencies: Long-Term Climate, Medium-Term Climate, Extreme Weather, Biosphere & Ecosystems, and Solid Earth, Ice Sheets, & Sea Level. Each workgroup was directed to scope out one Big Question, including not just the science but the observational and modeling requirements, the information system requirements, and the applications and benefits to society. This first set of five Big Questions is now in hand and has been presented to the ESE Director. It includes: water resources, intraseasonal predictability, tropical cyclogenesis, invasive species, and sea level. Each of these topics will be discussed briefly. How this effort fits into the NEXT vision exercise and into Administrator O'Keefe's new vision for NASA will also be discussed.

  7. Computation and parallel implementation for early vision

    Science.gov (United States)

    Gualtieri, J. Anthony

    1990-01-01

    The problem of early vision is to transform one or more retinal illuminance images-pixel arrays-to image representations built out of such primitive visual features such as edges, regions, disparities, and clusters. These transformed representations form the input to later vision stages that perform higher level vision tasks including matching and recognition. Researchers developed algorithms for: (1) edge finding in the scale space formulation; (2) correlation methods for computing matches between pairs of images; and (3) clustering of data by neural networks. These algorithms are formulated for parallel implementation of SIMD machines, such as the Massively Parallel Processor, a 128 x 128 array processor with 1024 bits of local memory per processor. For some cases, researchers can show speedups of three orders of magnitude over serial implementations.

  8. William Blake's visions and the Unio Artistica

    Directory of Open Access Journals (Sweden)

    Bo H. Lindberg

    1970-02-01

    Full Text Available To Blake art was a vision of the spiritual world, as he could talk about "Poetry, Painting & Music, the three Powers in Man of conversing with Paradise, which the flood did not Sweep away." Every work of art is an open window into eternity. God appears to man in art. Artistic inspiration is the same as the union with God. There is an unio artistica, a sister to the unio mystica. Blake accepts that reason cannot grasp the divine vision and understand it. That is why he always talks of the vision as appearing in stronger and better lineaments, and a stronger and better light than nature can produce or mortal and perishing organs can apprehend. But art can grasp it. The central conception of mysticism, the undescribable unio mystica, is present in Blake. He is a mystic. The only difference between Blake and the classical mystics is in terminology. When they say "God" Blake very often says "Art".

  9. True Visions The Emergence of Ambient Intelligence

    CERN Document Server

    Aarts, Emile

    2006-01-01

    Ambient intelligence (AI) refers to a developing technology that will increasingly make our everyday environment sensitive and responsive to our presence. The AI vision requires technology invisibly embedded in our everyday surroundings, present whenever we need it that will lead to the seamless integration of lighting, sounds, vision, domestic appliances, and personal healthcare products to enhance our living experience. Written for the non-specialist seeking an authoritative but accessible overview of this interdisciplinary field, True Visions explains how the devices making up the AI world will operate collectively using information and intelligence hidden in the wireless network connecting them. Expert contributions address key AI components such as smart materials and textiles, system architecture, mobile computing, broadband communication, and underlying issues of human-environment interactions. It seeks to unify the perspectives of scientists from diverse backgrounds ranging from the physics of materia...

  10. Vision screening for amblyopia in childhood.

    Science.gov (United States)

    Powell, Christine; Hatt, Sarah R

    2009-07-08

    Amblyopia is a reversible deficit of vision that has to be treated within the sensitive period for visual development. Screening programmes have been set up to detect this largely asymptomatic condition and refer children for treatment while an improvement in vision is still possible. The value of such programmes and the optimum protocol for administering them remain controversial. The objective of this review was to evaluate the effectiveness of vision screening in reducing the prevalence of amblyopia. We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2008), MEDLINE (January 1950 to August 2008) and EMBASE (January 1947 to August 2008). The electronic databases were last searched on 15 August 2008. No language restrictions were placed on these searches. No handsearching was done. We planned to analyse data from randomised controlled trials and cluster-randomised trials comparing the prevalence of amblyopia in screened versus unscreened populations. Two authors independently assessed study abstracts identified by the electronic searches. Full text copies of appropriate studies were obtained and, where necessary, authors were contacted. No data were available for analysis and no meta-analysis was performed. Despite the large amount of literature available regarding vision screening no trials designed to compare the prevalence of amblyopia in screened versus unscreened populations were found. The lack of data from randomised controlled trials makes it difficult to analyse the impact of existing screening programmes on the prevalence of amblyopia. The absence of such evidence cannot be taken to mean that vision screening is not beneficial; simply that this intervention has not yet been tested in robust trials. To facilitate such trials normative data on age-appropriate vision tests need to be available and a consensus reached regarding the definition of amblyopia. In addition, the consequences of living with untreated

  11. Nuclear physics with polarized particles

    CERN Document Server

    Paetz gen Schieck, Hans

    2012-01-01

    The measurement of spin-polarization observables in reactions of nuclei and particles is of great utility and advantage when the effects of single-spin sub-states are to be investigated. Indeed, the unpolarized differential cross-section encompasses the averaging over the spin states of the particles, and thus loses details of the interaction process. This introductory text combines, in a single volume, course-based lecture notes on spin physics and on polarized-ion sources with the aim of providing a concise yet self-contained starting point for newcomers to the field, as well as for lecturers in search of suitable material for their courses and seminars. A significant part of the book is devoted to introducing the formal theory-a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear rea...

  12. Computational and cognitive neuroscience of vision

    CERN Document Server

    2017-01-01

    Despite a plethora of scientific literature devoted to vision research and the trend toward integrative research, the borders between disciplines remain a practical difficulty. To address this problem, this book provides a systematic and comprehensive overview of vision from various perspectives, ranging from neuroscience to cognition, and from computational principles to engineering developments. It is written by leading international researchers in the field, with an emphasis on linking multiple disciplines and the impact such synergy can lead to in terms of both scientific breakthroughs and technology innovations. It is aimed at active researchers and interested scientists and engineers in related fields.

  13. Review of intelligent bionic vision navigation

    Science.gov (United States)

    Wu, Peng; Mu, Rongjun; Deng, Yanpeng

    2017-11-01

    With the popularization of intelligent equipment such as UAV (Unmanned Aerial Vehicle) and UV (Unmanned Vehicle), their demands for autonomy, independence and intelligence of navigation gradually increase, and traditional navigation methods can't meet this demand. In order to make a thorough study, a review of intelligent bionic vision navigation methods is made on its background, research status and related fields. Through the analysis and summarization of the above information, the development trend of intelligent bionic vision navigation is pointed out, and its advantages and disadvantages are discussed.

  14. Efficient discrete Gabor functions for robot vision

    Science.gov (United States)

    Weiman, Carl F. R.

    1994-03-01

    A new discrete Gabor function provides subpixel resolution of phase while overcoming many of the computational burdens of current approaches to Gabor function implementation. Applications include hyperacuity measurement of binocular disparity and optic flow for stereo vision. Convolution is avoided by exploiting band-pass to subsample the image plane. A general purpose front end processor for robot vision, based on a wavelet interpretation of this discrete Gabor function, can be constructed by tessellating and pyramiding the elementary filter. Computational efficiency opens the door to real-time implementation which mimics many properties of the simple and complex cells in the visual cortex.

  15. Technology for NASA's Planetary Science Vision 2050.

    Science.gov (United States)

    Lakew, B.; Amato, D.; Freeman, A.; Falker, J.; Turtle, Elizabeth; Green, J.; Mackwell, S.; Daou, D.

    2017-01-01

    NASAs Planetary Science Division (PSD) initiated and sponsored a very successful community Workshop held from Feb. 27 to Mar. 1, 2017 at NASA Headquarters. The purpose of the Workshop was to develop a vision of planetary science research and exploration for the next three decades until 2050. This abstract summarizes some of the salient technology needs discussed during the three-day workshop and at a technology panel on the final day. It is not meant to be a final report on technology to achieve the science vision for 2050.

  16. Does vision work well enough for industry?

    DEFF Research Database (Denmark)

    Hagelskjær, Frederik; Krüger, Norbert; Buch, Anders Glent

    2018-01-01

    A multitude of pose estimation algorithms has been developed in the last decades and many proprietary computer vision packages exist which can simplify the setup process. Despite this, pose estimation still lacks the ease of use that robots have attained in the industry. The statement ”vision does...... not work” is still not uncommon in the industry, even from integrators. This points to difficulties in setting up solutions in industrial applications. In this paper, we analyze and investigate the current usage of pose estimation algorithms. A questionnaire was sent out to both university and industry...

  17. Empirical evaluation methods in computer vision

    CERN Document Server

    Christensen, Henrik I

    2002-01-01

    This book provides comprehensive coverage of methods for the empirical evaluation of computer vision techniques. The practical use of computer vision requires empirical evaluation to ensure that the overall system has a guaranteed performance. The book contains articles that cover the design of experiments for evaluation, range image segmentation, the evaluation of face recognition and diffusion methods, image matching using correlation methods, and the performance of medical image processing algorithms. Sample Chapter(s). Foreword (228 KB). Chapter 1: Introduction (505 KB). Contents: Automate

  18. Vision models for 3D surfaces

    Science.gov (United States)

    Mitra, Sunanda

    1992-11-01

    Different approaches to computational stereo to represent human stereo vision have been developed over the past two decades. The Marr-Poggio theory of human stereo vision is probably the most widely accepted model of the human stereo vision. However, recently developed motion stereo models which use a sequence of images taken by either a moving camera or a moving object provide an alternative method of achieving multi-resolution matching without the use of Laplacian of Gaussian operators. While using image sequences, the baseline between two camera positions for a image pair is changed for the subsequent image pair so as to achieve different resolution for each image pair. Having different baselines also avoids the inherent occlusion problem in stereo vision models. The advantage of using multi-resolution images acquired by camera positioned at different baselines over those acquired by LOG operators is that one does not have to encounter spurious edges often created by zero-crossings in the LOG operated images. Therefore in designing a computer vision system, a motion stereo model is more appropriate than a stereo vision model. However, in some applications where only a stereo pair of images are available, recovery of 3D surfaces of natural scenes are possible in a computationally efficient manner by using cepstrum matching and regularization techniques. Section 2 of this paper describes a motion stereo model using multi-scale cepstrum matching for the detection of disparity between image pairs in a sequence of images and subsequent recovery of 3D surfaces from depth-map obtained by a non convergent triangulation technique. Section 3 presents a 3D surface recovery technique from a stereo pair using cepstrum matching for disparity detection and cubic B-splines for surface smoothing. Section 4 contains the results of 3D surface recovery using both of the techniques mentioned above. Section 5 discusses the merit of 2D cepstrum matching and cubic B

  19. Sharp Vision Reveals Intimacy of Stars

    Science.gov (United States)

    2005-11-01

    Sharp Vision Reveals Intimacy of Stars AMBER instrument on VLTI Probes Environment of Stars Using the newly installed AMBER instrument on ESO's Very Large Telescope Interferometer, which combines the light from two or three 8.2-m Unit Telescopes thereby amounting to observe with a telescope of 40 to 90 metres in diameter, two international teams of astronomers observed with unprecedented detail the environment of two stars. One is a young, still-forming star and the new results provide useful information on the conditions leading to the creation of planets. The other is on the contrary a star entering the latest stages of its life. The astronomers found, in both cases, evidence for a surrounding disc. ESO PR Photo 36a/05 ESO PR Photo 36a/05 The Young Stellar Object MWC 297 (Artist's View) [Preview - JPEG: 400 x 502 pix - 50k] [Normal - JPEG: 800 x 1004 pix - 330k] A first group of astronomers [1], led by Fabien Malbet from the Laboratoire d'Astrophysique de Grenoble, France, studied the young 10-solar mass stellar object MWC 297, which is still in the very early stage of its life [2]. "This scientific breakthrough opens the doors to an especially detailed scrutiny of the very close environment of young stars and will bring us invaluable knowledge on how planets form", says Malbet. It is amazing to see the amount of details the astronomers could achieve while observing an object located more than 800 light-years away and hidden by a large amount of gas and dust. They found the object to be surrounded by a proto-planetary disc extending to about the size of our Solar System, but truncated in his inner part until about half the distance between the Earth and the Sun. Moreover, the scientists found the object to be surrounded by an outflowing wind, the velocity of which increased by a factor 9, from about 70 km/s near the disc to 600 km/s in the polar regions [3]. "The reason why the inner part of the disc should be truncated is not clear", adds Malbet. "This raises

  20. Spectral and spatial properties of polarized light reflections from the arms of squid (Loligo pealeii) and cuttlefish (Sepia officinalis L.).

    Science.gov (United States)

    Chiou, Tsyr-Huei; Mäthger, Lydia M; Hanlon, Roger T; Cronin, Thomas W

    2007-10-01

    On every arm of cuttlefish and squid there is a stripe of high-reflectance iridophores that reflects highly polarized light. Since cephalopods possess polarization vision, it has been hypothesized that these polarized stripes could serve an intraspecific communication function. We determined how polarization changes when these boneless arms move. By measuring the spectral and polarizing properties of the reflected light from samples at various angles of tilt and rotation, we found that the actual posture of the arm has little or no effect on partial polarization or the e-vector angle of the reflected light. However, when the illumination angle changed, the partial polarization of the reflected light also changed. The spectral reflections of the signals were also affected by the angle of illumination but not by the orientation of the sample. Electron microscope samples showed that these stripes are composed of several groups of multilayer platelets within the iridophores. The surface normal to each group is oriented at a different angle, which produces essentially constant reflection of polarized light over a range of viewing angles. These results demonstrate that cuttlefish and squid could send out reliable polarization signals to a receiver regardless of arm orientation.

  1. Few-body experiments with polarized beams and polarized targets

    International Nuclear Information System (INIS)

    Simmons, J.E.

    1983-01-01

    A survey is presented concerning recent polarization experiments in the elastic p-d, p- 3 He, and p- 4 He systems. Mention is made of selected neutron experiments. The nominal energy range is 10 to 1000 MeV. Recent results and interpretations of the p-d system near 10 MeV are discussed. New experiments on the energy dependence of back angle p-d tensor polarization are discussed with respect to resolution of discrepancies and difficulty of theoretical interpretation. Progress is noted concerning multiple scattering interpretation of forward p-d deuteron polarization. Some new results are presented concerning the p- 3 He system and higher energy p- 4 He polarization experiments. 52 references

  2. Microbial metabolite butyrate facilitates M2 macrophage polarization and function.

    Science.gov (United States)

    Ji, Jian; Shu, Dingming; Zheng, Mingzhu; Wang, Jie; Luo, Chenglong; Wang, Yan; Guo, Fuyou; Zou, Xian; Lv, Xiaohui; Li, Ying; Liu, Tianfei; Qu, Hao

    2016-04-20

    Metabolites from intestinal microbes modulate the mucosal immune system by regulating the polarization and expansion of T cells. Whether the microbial metabolites influence macrophage polarization, however, is poorly understood. Here, we show that the large bowel microbial fermentation product, butyrate, facilitates M2 macrophage polarization, in vitro and in vivo. The supernatant from butyrate-treated M2 macrophage increased the migration and enhanced the wound closure rate of MLE-12 cells. Butyrate attenuated intestinal inflammation in mice with dextran sulfate sodium (DSS)-induced colitis, with a significant increase in colonic expression of the M2 macrophage-associated protein, Arg1. M2 macrophage treated with butyrate, had increased activation of the H3K9/STAT6 signaling pathway, suggesting a mechanism for butyrate facilitated M2 macrophage polarization. Collectively, our study indicated that commensal microbe-derived butyrate is a novel activator of STAT6-mediated transcription through H3K9 acetylation driving M2 macrophage polarization, and delineated new insights into the immune interplay underlying inflammatory bowel disease.

  3. Dietary biomagnification of organochlorine contaminants in Alaskan polar bears

    Science.gov (United States)

    Bentzen, T.W.; Follmann, Erich H.; Amstrup, Steven C.; York, G.S.; Wooller, M.J.; Muir, D.C.G.; O'Hara, T. M.

    2008-01-01

    Concentrations of organochlorine contaminants in the adipose tissue of polar bears (Ursus maritimus Phipps, 1774) vary throughout the Arctic. The range in concentrations has not been explained fully by bear age, sex, condition, location, or reproductive status. Dietary pathways expose polar bears to a variety of contaminant profiles and concentrations. Prey range from lower trophic level bowhead whales (Balaena mysticetus L., 1758), one of the least contaminated marine mammals, to highly contaminated upper trophic level ringed seals (Phoca hispida (Schreber, 1775)). We used ??15N and ??13C signatures to estimate the trophic status of 42 polar bears sampled along Alaska's Beaufort Sea coast to determine the relationship between organochlorine concentration and trophic level. The ?? 15N values in the cellular portions of blood ranged from 18.2% to 20.7%. We found strong positive relationships between concentrations of the most recalcitrant polychlorinated biphenyls (PCBs) and ??15N values in models incorporating age, lipid content, and ??13C value. Specifically these models accounted for 67% and 76% of the variation in PCB153 and oxychlordane concentration in male polar bears and 85% and 93% in females, respectively. These results are strong indicators of variation in diet and biomagnification of organochlorines among polar bears related to their sex, age, and trophic position. ?? 2008 NRC.

  4. Elite Polarization and Public Opinion

    DEFF Research Database (Denmark)

    Robison, Joshua; Mullinix, Kevin

    2016-01-01

    Elite polarization has reshaped American politics and is an increasingly salient aspect of news coverage within the United States. As a consequence, a burgeoning body of research attempts to unravel the effects of elite polarization on the mass public. However, we know very little about how...... attitudes. In our first study, we show that criticism of polarization leads partisans to more positively evaluate the argument offered by their non-preferred party, increases support for bi-partisanship, but ultimately does not change the extent to which partisans follow their party’s policy endorsements...

  5. Acceleration of polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1998-01-01

    The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

  6. Polarimetry with azimuthally polarized light

    Science.gov (United States)

    de Sande, Juan Carlos González; Piquero, Gemma; Santarsiero, Massimo

    2018-03-01

    Nonuniformly polarized light can be used for Mueller polarimetry of homogeneous linear samples. In this work, a set up based on using azimuthally polarized input light and a modified commercial light polarimeter is proposed and developed. With this set up, a Mueller submatrix of a sample can be obtained by measuring the Stokes parameters at only three different positions across the output beam section. Symmetry constraints for linear deterministic samples allow the complete Mueller matrix to be deduced for this kind of specimens. The experimental results obtained for phase plates and for a linear polarizer confirm the validity of the proposed method.

  7. Polarized deuteron elastic scattering from a polarized proton target

    International Nuclear Information System (INIS)

    Schmelzer, R.; Kuiper, H.; Schoeberl, M.; Berber, S.; Hilmert, H.; Koeppel, R.; Pferdmenges, R.; Zankel, H.

    1983-01-01

    Measurements are reported of the spin correlation parameter Cy,y for the elastic scattering of 10.0 MeV vector polarized deuterons from a polarized proton target at five CM angles (76 0 ,85 0 ,98 0 ,115 0 ,132 0 ). The experimental results are compared with different predictions. A Faddeev type calculation on the basis of local potentials also including approximate Coulomb distortion is favoured by our experimental results. (orig.)

  8. PolarHub: A Global Hub for Polar Data Discovery

    Science.gov (United States)

    Li, W.

    2014-12-01

    This paper reports the outcome of a NSF project in developing a large-scale web crawler PolarHub to discover automatically the distributed polar dataset in the format of OGC web services (OWS) in the cyberspace. PolarHub is a machine robot; its goal is to visit as many webpages as possible to find those containing information about polar OWS, extract this information and store it into the backend data repository. This is a very challenging task given huge data volume of webpages on the Web. Three unique features was introduced in PolarHub to make it distinctive from earlier crawler solutions: (1) a multi-task, multi-user, multi-thread support to the crawling tasks; (2) an extensive use of thread pool and Data Access Object (DAO) design patterns to separate persistent data storage and business logic to achieve high extendibility of the crawler tool; (3) a pattern-matching based customizable crawling algorithm to support discovery of multi-type geospatial web services; and (4) a universal and portable client-server communication mechanism combining a server-push and client pull strategies for enhanced asynchronous processing. A series of experiments were conducted to identify the impact of crawling parameters to the overall system performance. The geographical distribution pattern of all PolarHub identified services is also demonstrated. We expect this work to make a major contribution to the field of geospatial information retrieval and geospatial interoperability, to bridge the gap between data provider and data consumer, and to accelerate polar science by enhancing the accessibility and reusability of adequate polar data.

  9. Efficacy of vision therapy in children with learning disability and associated binocular vision anomalies.

    Science.gov (United States)

    Hussaindeen, Jameel Rizwana; Shah, Prerana; Ramani, Krishna Kumar; Ramanujan, Lalitha

    To report the frequency of binocular vision (BV) anomalies in children with specific learning disorders (SLD) and to assess the efficacy of vision therapy (VT) in children with a non-strabismic binocular vision anomaly (NSBVA). The study was carried out at a centre for learning disability (LD). Comprehensive eye examination and binocular vision assessment was carried out for 94 children (mean (SD) age: 15 (2.2) years) diagnosed with specific learning disorder. BV assessment was done for children with best corrected visual acuity of ≥6/9 - N6, cooperative for examination and free from any ocular pathology. For children with a diagnosis of NSBVA (n=46), 24 children were randomized to VT and no intervention was provided to the other 22 children who served as experimental controls. At the end of 10 sessions of vision therapy, BV assessment was performed for both the intervention and non-intervention groups. Binocular vision anomalies were found in 59 children (62.8%) among which 22% (n=13) had strabismic binocular vision anomalies (SBVA) and 78% (n=46) had a NSBVA. Accommodative infacility (AIF) was the commonest of the NSBVA and found in 67%, followed by convergence insufficiency (CI) in 25%. Post-vision therapy, the intervention group showed significant improvement in all the BV parameters (Wilcoxon signed rank test, pvision disorders and vision therapy plays a significant role in improving the BV parameters. Children with SLD should be screened for BV anomalies as it could potentially be an added hindrance to the reading difficulty in this special population. Copyright © 2017 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  10. On the functional relevance of frontal cortex for passive and voluntarily controlled bistable vision.

    Science.gov (United States)

    de Graaf, Tom A; de Jong, Maartje C; Goebel, Rainer; van Ee, Raymond; Sack, Alexander T

    2011-10-01

    In bistable vision, one constant ambiguous stimulus leads to 2 alternating conscious percepts. This perceptual switching occurs spontaneously but can also be influenced through voluntary control. Neuroimaging studies have reported that frontal regions are activated during spontaneous perceptual switches, leading some researchers to suggest that frontal regions causally induce perceptual switches. But the opposite also seems possible: frontal activations may themselves be caused by spontaneous switches. Classically implicated in attentional processes, these same regions are also candidates for the origins of voluntary control over bistable vision. Here too, it remains unknown whether frontal cortex is actually functionally relevant. It is even possible that spontaneous perceptual switches and voluntarily induced switches are mediated by the same top-down mechanisms. To directly address these issues, we here induced "virtual lesions," with transcranial magnetic stimulation, in frontal, parietal, and 2 lower level visual cortices using an established ambiguous structure-from-motion stimulus. We found that dorsolateral prefrontal cortex was causally relevant for voluntary control over perceptual switches. In contrast, we failed to find any evidence for an active role of frontal cortex in passive bistable vision. Thus, it seems the same pathway used for willed top-down modulation of bistable vision is not used during passive bistable viewing.

  11. FijiWingsPolarity: An open source toolkit for semi-automated detection of cell polarity.

    Science.gov (United States)

    Dobens, Leonard L; Shipman, Anna; Axelrod, Jeffrey D

    2017-12-22

    Epithelial cells are defined by apical-basal and planar cell polarity (PCP) signaling, the latter of which establishes an orthogonal plane of polarity in the epithelial sheet. PCP signaling is required for normal cell migration, differentiation, stem cell generation and tissue repair, and defects in PCP have been associated with developmental abnormalities, neuropathologies and cancers. While the molecular mechanism of PCP is incompletely understood, the deepest insights have come from Drosophila, where PCP is manifest in hairs and bristles across the adult cuticle and organization of the ommatidia in the eye. Fly wing cells are marked by actin-rich trichome structures produced at the distal edge of each cell in the developing wing epithelium and in a mature wing the trichomes orient collectively in the distal direction. Genetic screens have identified key PCP signaling pathway components that disrupt trichome orientation, which has been measured manually in a tedious and error prone process. Here we describe a set of image processing and pattern-recognition macros that can quantify trichome arrangements in micrographs and mark these directly by color, arrow or colored arrow to indicate trichome location, length and orientation. Nearest neighbor calculations are made to exploit local differences in orientation to better and more reliably detect and highlight local defects in trichome polarity. We demonstrate the use of these tools on trichomes in adult wing preps and on actin-rich developing trichomes in pupal wing epithelia stained with phalloidin. FijiWingsPolarity is freely available and will be of interest to a broad community of fly geneticists studying the effect of gene function on PCP.

  12. Comparing visual representations across human fMRI and computational vision.

    Science.gov (United States)

    Leeds, Daniel D; Seibert, Darren A; Pyles, John A; Tarr, Michael J

    2013-11-22

    Feedforward visual object perception recruits a cortical network that is assumed to be hierarchical, progressing from basic visual features to complete object representations. However, the nature of the intermediate features related to this transformation remains poorly understood. Here, we explore how well different computer vision recognition models account for neural object encoding across the human cortical visual pathway as measured using fMRI. These neural data, collected during the viewing of 60 images of real-world objects, were analyzed with a searchlight procedure as in Kriegeskorte, Goebel, and Bandettini (2006): Within each searchlight sphere, the obtained patterns of neural activity for all 60 objects were compared to model responses for each computer recognition algorithm using representational dissimilarity analysis (Kriegeskorte et al., 2008). Although each of the computer vision methods significantly accounted for some of the neural data, among the different models, the scale invariant feature transform (Lowe, 2004), encoding local visual properties gathered from "interest points," was best able to accurately and consistently account for stimulus representations within the ventral pathway. More generally, when present, significance was observed in regions of the ventral-temporal cortex associated with intermediate-level object perception. Differences in model effectiveness and the neural location of significant matches may be attributable to the fact that each model implements a different featural basis for representing objects (e.g., more holistic or more parts-based). Overall, we conclude that well-known computer vision recognition systems may serve as viable proxies for theories of intermediate visual object representation.

  13. Planar Cell Polarity Controls Pancreatic Beta Cell Differentiation and Glucose Homeostasis

    DEFF Research Database (Denmark)

    Cortijo, Cedric; Gouzi, Mathieu; Tissir, Fadel

    2012-01-01

    Planar cell polarity (PCP) refers to the collective orientation of cells within the epithelial plane. We show that progenitor cells forming the ducts of the embryonic pancreas express PCP proteins and exhibit an active PCP pathway. Planar polarity proteins are acquired at embryonic day 11.5 synch...... that tridimensional organization and collective communication of cells are needed in the pancreatic epithelium in order to generate appropriate numbers of endocrine cells....

  14. The function of the frizzled pathway in the Drosophila wing is dependent on inturned and fuzzy.

    OpenAIRE

    Lee, Haeryun; Adler, Paul N

    2002-01-01

    The Drosophila epidermis is characterized by a dramatic planar or tissue polarity. The frizzled pathway has been shown to be a key regulator of planar polarity for hairs on the wing, ommatidia in the eye, and sensory bristles on the notum. We have investigated the genetic relationships between putative frizzled pathway downstream genes inturned, fuzzy, and multiple wing hairs (inturned-like genes) and upstream genes such as frizzled, prickle, and starry night (frizzled-like genes). Previous d...

  15. A Kinome RNAi Screen inDrosophilaIdentifies Novel Genes Interacting with Lgl, aPKC, and Crb Cell Polarity Genes in Epithelial Tissues.

    Science.gov (United States)

    Parsons, Linda M; Grzeschik, Nicola A; Amaratunga, Kasun; Burke, Peter; Quinn, Leonie M; Richardson, Helena E

    2017-08-07

    In both Drosophila melanogaster and mammalian systems, epithelial structure and underlying cell polarity are essential for proper tissue morphogenesis and organ growth. Cell polarity interfaces with multiple cellular processes that are regulated by the phosphorylation status of large protein networks. To gain insight into the molecular mechanisms that coordinate cell polarity with tissue growth, we screened a boutique collection of RNAi stocks targeting the kinome for their capacity to modify Drosophila "cell polarity" eye and wing phenotypes. Initially, we identified kinase or phosphatase genes whose depletion modified adult eye phenotypes associated with the manipulation of cell polarity complexes (via overexpression of Crb or aPKC). We next conducted a secondary screen to test whether these cell polarity modifiers altered tissue overgrowth associated with depletion of Lgl in the wing. These screens identified Hippo, Jun kinase (JNK), and Notch signaling pathways, previously linked to cell polarity regulation of tissue growth. Furthermore, novel pathways not previously connected to cell polarity regulation of tissue growth were identified, including Wingless (Wg/Wnt), Ras, and lipid/Phospho-inositol-3-kinase (PI3K) signaling pathways. Additionally, we demonstrated that the "nutrient sensing" kinases Salt Inducible Kinase 2 and 3 ( SIK2 and 3 ) are potent modifiers of cell polarity phenotypes and regulators of tissue growth. Overall, our screen has revealed novel cell polarity-interacting kinases and phosphatases that affect tissue growth, providing a platform for investigating molecular mechanisms coordinating cell polarity and tissue growth during development. Copyright © 2017 Parsons et al.

  16. Polar source analysis : technical memorandum

    Science.gov (United States)

    2017-09-29

    The following technical memorandum describes the development, testing and analysis of various polar source data sets. The memorandum also includes recommendation for potential inclusion in future releases of AEDT. This memorandum is the final deliver...

  17. Anodic Concentration Polarization in SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Williford, Rick E.; Chick, Lawrence A.; Maupin, Gary D.; Simner, Steve P.; Stevenson, Jeffry W.; Khaleel, Mohammad A.; Wachsman, ED, et al

    2003-08-01

    Concentration polarization is important because it determines the maximum power output of a solid oxide fuel cell (SOFC) at high fuel utilization. Anodic concentration polarization occurs when the demand for reactants exceeds the capacity of the porous ceramic anode to supply them by gas diffusion mechanisms. High tortuosities (bulk diffusion resistances) are often assumed to explain this behavior. However, recent experiments show that anodic concentration polarization originates in the immediate vicinity of the reactive triple phase boundary (TPB) sites near the anode/electrolyte interface. A model is proposed to describe how concentration polarization is controlled by two localized phenomena: competitive adsorption of reactants in areas adjacent to the reactive TPB sites, followed by relatively slow surface diffusion to the reactive sites. Results suggest that future SOFC design improvements should focus on optimization of the reactive area, adsorption, and surface diffusion at the anode/electrolyte interface.

  18. The definition of cross polarization

    DEFF Research Database (Denmark)

    Ludwig, Arthur

    1973-01-01

    There are at least three different definitions of cross polarization used in the literature. The alternative definitions are discussed with respect to several applications, and the definition which corresponds to one standard measurement practice is proposed as the best choice....

  19. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: Progres-Q24 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016

  20. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: RVO:67985998 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016