Factors affecting cone production in Pinus pinaster Ait.: lack of growth-reproduction trade-offs but significant effects of climate and tree and stand characteristics

Energy Technology Data Exchange (ETDEWEB)

Bravo, F.; Maguire, D.A.; González-Martínez, S.G.

2017-11-01

Aim of study: Our main goal is to determine the relationship between cone production and radial growth in Pinus pinaster Ait. under different climatic conditions across the Iberian Peninsula. Area of study: Coca Intensive Sampling Plateau, Northern Plateau (Spain). Material and methods: Cone counts were conducted on an intensive monitoring plot in Coca (North-Central Spain) during the years 2000, 2006 and 2007. A ZIP (zero-inflated Poisson) model was adjusted for simultaneously estimating the probability of obtaining crop cones and its amount. The Northern Atlantic Oscillation (NAO) index was used as explanatory variable, together with a wide variety of tree and local stand variables. Climate (as evaluated by NAO), local stand density (here estimated from the six nearest trees), tree size and vigor, competition and growth efficiency significantly influenced both occurrence and intensity of cone production. Main results: ZIP models for predicting reproductive effort seems an adequate tool to predict reproductive responses to climatic fluctuations and the resulting future species distribution in the face of climate change, as well as to identify silviculture actions that would promote reproductive success in naturally-regenerated stands, list and discuss relevant results (including numeric values of experimental results). Research highlights: Climate, stand density and tree conditions (size and vigor, competition and growth efficiency) influence significantly both cone occurrence and intensity of fruiting as shown by a ZIP model. As the climate variables included in the model (based on Northern Atlantic Oscillation, NAO) are general and easily obtained, the proposed model has practical applicability to predicting Pinus pinaster cone production in the Iberian Peninsula.

Factors affecting cone production in Pinus pinaster Ait.: lack of growth-reproduction trade-offs but significant effects of climate and tree and stand characteristics

Directory of Open Access Journals (Sweden)

Felipe Bravo

2017-10-01

Full Text Available Aim of study: Our main goal is to determine the relationship between cone production and radial growth in Pinus pinaster Ait. under different climatic conditions across the Iberian Peninsula. Area of study: Coca Intensive Sampling Plateau, Northern Plateau (Spain. Material and methods: Cone counts were conducted on an intensive monitoring plot in Coca (North-Central Spain during the years 2000, 2006 and 2007. A ZIP (zero-inflated Poisson model was adjusted for simultaneously estimating the probability of obtaining crop cones and its amount. The Northern Atlantic Oscillation (NAO index was used as explanatory variable, together with a wide variety of tree and local stand variables. Climate (as evaluated by NAO, local stand density (here estimated from the six nearest trees, tree size and vigor, competition and growth efficiency significantly influenced both occurrence and intensity of cone production. Main results: ZIP models for predicting reproductive effort seems an adequate tool to predict reproductive responses to climatic fluctuations and the resulting future species distribution in the face of climate change, as well as to identify silviculture actions that would promote reproductive success in naturally-regenerated stands, list and discuss relevant results (including numeric values of experimental results. Research highlights: Climate, stand density and tree conditions (size and vigor, competition and growth efficiency influence significantly both cone occurrence and intensity of fruiting as shown by a ZIP model. As the climate variables included in the model (based on Northern Atlantic Oscillation, NAO are general and easily obtained, the proposed model has practical applicability to predicting Pinus pinaster cone production in the Iberian Peninsula.

Factors affecting cone production in Pinus pinaster Ait.: lack of growth-reproduction trade-offs but significant effects of climate and tree and stand characteristics

International Nuclear Information System (INIS)

Bravo, F.; Maguire, D.A.; González-Martínez, S.G.

2017-01-01

Aim of study: Our main goal is to determine the relationship between cone production and radial growth in Pinus pinaster Ait. under different climatic conditions across the Iberian Peninsula. Area of study: Coca Intensive Sampling Plateau, Northern Plateau (Spain). Material and methods: Cone counts were conducted on an intensive monitoring plot in Coca (North-Central Spain) during the years 2000, 2006 and 2007. A ZIP (zero-inflated Poisson) model was adjusted for simultaneously estimating the probability of obtaining crop cones and its amount. The Northern Atlantic Oscillation (NAO) index was used as explanatory variable, together with a wide variety of tree and local stand variables. Climate (as evaluated by NAO), local stand density (here estimated from the six nearest trees), tree size and vigor, competition and growth efficiency significantly influenced both occurrence and intensity of cone production. Main results: ZIP models for predicting reproductive effort seems an adequate tool to predict reproductive responses to climatic fluctuations and the resulting future species distribution in the face of climate change, as well as to identify silviculture actions that would promote reproductive success in naturally-regenerated stands, list and discuss relevant results (including numeric values of experimental results). Research highlights: Climate, stand density and tree conditions (size and vigor, competition and growth efficiency) influence significantly both cone occurrence and intensity of fruiting as shown by a ZIP model. As the climate variables included in the model (based on Northern Atlantic Oscillation, NAO) are general and easily obtained, the proposed model has practical applicability to predicting Pinus pinaster cone production in the Iberian Peninsula.

CNS role evolution.

Science.gov (United States)

Payne, J L; Baumgartner, R G

1996-01-01

THE CNS ROLE has been actualized in a variety of ways. Flexibility-inherent in the role-and the revolution in health care consciousness tend to place the CNS at risk for criticism regarding value to the organization. At Vanderbilt University Medical Center, a CNS task force evaluated the current reality of CNS practice and recommended role changes to include the financial analysis of patient care. After incorporating a financial perspective into our present practice, we have embarked on an interesting journey of post-Master's degree study, that of the tertiary care nurse practitioner. This practice option could elevated the clinical and financial aspects of providing cost-effective health care to a more autonomous role form; however, the transition has been challenging. Since 1990, the American Nurses Association has recommended that nursing school curricula change to meet the needs of the health care environment and provide increased career flexibility through creating one advanced degree incorporating both CNS and NP functions. Swiftly moving past differences and toward similarities will bridge the gap for advanced practice nurses in the future.

Isolated vasculitis of the CNS

International Nuclear Information System (INIS)

Block, F.; Reith, W.

2000-01-01

Vasculitis is a rare cause for disease of the CNS. The isolated vasculitis of the CNS is restricted to the CNS whereas other forms of vasculitis affect various organs including the CNS. Headache, encephalopathy, focal deficits and epileptic seizures are the major symptoms suggestive for vasculitis. One major criterion of the isolated vasculitis of the CNS is the lack of evidence for other vasculitis forms or for pathology of other organs. Angiography displays multifocal segmental stenosis of intracranial vessels. MRI demonstrates multiple lesions which in part show enhancement after gadolinium. A definite diagnosis can only be made on the grounds of biopsy from leptomeninges and parenchyma. Therapy consists of corticosteroids and cyclophosphamid. (orig.) [de

Loss-cone-driven ion cyclotron waves in the magnetosphere

International Nuclear Information System (INIS)

Denton, R.E.; Hudson, M.K.; Roth, I.

1992-01-01

The theoretical properties of linear ion cyclotron waves propagating in the magnetosphere at arbitrary angles to the background magnetic field are explored. It is found that in some cases the linear wave growth of modes with oblique propagation can dominate that of the parallel propagating electromagnetic ion cyclotron (EMIC) wave. In particular, when the hot ring current protons have a loss cone and their temperature anisotropy A ≡ T perpendicular /T parallel - 1 is reduced, the parallel propagating EMIC wave becomes stable, while the obliquely propagating loss-cone-driven mode persists. The growth rate of the loss-cone-driven model depends strongly on the depth of the loss cone. Unlike the parallel propagating EMIC wave, it can be unstable with A = 0. Other conditions that favor the loss-cone-driven mode in comparison to the parallel mode are stronger background magnetic field, lower density of cold hydrogen, and a lower temperature for the hot anisotropic component of hydrogen. A simple analytical theory is presented which explains the scaling of the growth rate of the oblique mode with respect to various parameters. The loss-cone-driven mode is an electromagnetic mode which is preferentially nearly linearly polarized. It is nearly electrostatic in the sense that the wave electric field is aligned with the perpendicular (to B 0 ) component of the wave vector k and k perpendicular > k parallel . Since the electric and magnetic wave fields are perpendicular to B 0 , they would be difficult to distinguish from those of a linearly polarized parallel propagating electromagnetic wave with the same k parallel

Drosophila growth cones: a genetically tractable platform for the analysis of axonal growth dynamics.

Science.gov (United States)

Sánchez-Soriano, Natalia; Gonçalves-Pimentel, Catarina; Beaven, Robin; Haessler, Ulrike; Ofner-Ziegenfuss, Lisa; Ballestrem, Christoph; Prokop, Andreas

2010-01-01

The formation of neuronal networks, during development and regeneration, requires outgrowth of axons along reproducible paths toward their appropriate postsynaptic target cells. Axonal extension occurs at growth cones (GCs) at the tips of axons. GC advance and navigation requires the activity of their cytoskeletal networks, comprising filamentous actin (F-actin) in lamellipodia and filopodia as well as dynamic microtubules (MTs) emanating from bundles of the axonal core. The molecular mechanisms governing these two cytoskeletal networks, their cross-talk, and their response to extracellular signaling cues are only partially understood, hindering our conceptual understanding of how regulated changes in GC behavior are controlled. Here, we introduce Drosophila GCs as a suitable model to address these mechanisms. Morphological and cytoskeletal readouts of Drosophila GCs are similar to those of other models, including mammals, as demonstrated here for MT and F-actin dynamics, axonal growth rates, filopodial structure and motility, organizational principles of MT networks, and subcellular marker localization. Therefore, we expect fundamental insights gained in Drosophila to be translatable into vertebrate biology. The advantage of the Drosophila model over others is its enormous amenability to combinatorial genetics as a powerful strategy to address the complexity of regulatory networks governing axonal growth. Thus, using pharmacological and genetic manipulations, we demonstrate a role of the actin cytoskeleton in a specific form of MT organization (loop formation), known to regulate GC pausing behavior. We demonstrate these events to be mediated by the actin-MT linking factor Short stop, thus identifying an essential molecular player in this context.

Nanomedicines for the Treatment of CNS Diseases.

Science.gov (United States)

Reynolds, Jessica L; Mahato, Ram I

2017-03-01

Targeting and delivering macromolecular therapeutics to the central nervous system (CNS) has been a major challenge. The blood-brain barrier (BBB) is the main obstacle that must be overcome to allow compounds to reach their targets in the brain. Therefore, much effort has been channelled into improving transport of therapeutics across the BBB and into the CNS including the use of nanoparticles. In this thematic issue, several reviews and original research are presented that address "Nanomedicines for CNS Diseases." The articles in this issue are concentrated on either CNS-HIV disease or CNS tumors. In regards to CNS-HIV disease, there are two reviews that discuss the role of nanoparticles for improving the delivery of HIV therapeutics to the CNS. In addition, there are two original articles focusing on therapies for CNS-HIV, one of them uses nanoparticles for delivery of siRNA specific to a key protein in autophagy to microglia, and another discusses nanoparticle delivery of a soluble mediator to suppress neuroinflammation. Furthermore, a comprehensive review about gene therapy for CNS neurological diseases is also included. Finally, this issue also includes review articles on enhanced drug targeting to CNS tumors. These articles include a review on the use of nanoparticles for CNS tumors, a review on functionalization (ligands) of nanoparticles for drug targeting to the brain tumor by overcoming BBB, and the final review discusses the use of macrophages as a delivery vehicle to CNS tumors. This thematic issue provides a wealth of knowledge on using nanomedicines for CNS diseases.

The Rat Homolog of the Schizophrenia Susceptibility Gene ZNF804A Is Highly Expressed during Brain Development, Particularly in Growth Cones.

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Katja Hvid Hinna

Full Text Available A single nucleotide polymorphism in the ZNF804A gene, rs1344706, is associated with schizophrenia. The polymorphism has been suggested to alter fetal expression of ZNF804A. It has also been reported to be associated with altered cortical functioning and neural connectivity in the brain. Since developmental mechanisms are suggested in the pathophysiology for schizophrenia, expression of Zfp804A, the rat homolog of ZNF804A, was investigated in the developing rat brain. We found that expression of Zfp804A in most brain regions is developmentally regulated and peaks around birth, where after it decreases towards adult levels. This time point is developmentally the equivalent to the second trimester of fetal development in humans. An exception to this expression pattern is the hippocampus where the expression of Zfp804A appears to increase again in the adult brain. Using laser capture and quantitative PCR we found that Zfp804A mRNA expression in the adult rat hippocampus is highest in the CA1 sub region, where the overall firing rates of neurons is higher than in the CA3 region. In cultured cortical neurons Zfp804A mRNA expression peaked at day 4 and then decreased. The ZFP804A protein expression was therefore investigated with immunochemistry in such cultures. Interestingly, before day 4, the protein is mostly found in the perinuclear region of the cell but at day 4, ZFP804A was instead found throughout the cell and particularly in the growth cones. In conclusion we demonstrate that Zfp804A increases in the rat brain at the time of birth, coinciding with neuronal differentiation. We also show that ZFP804A is localized to growth cones of growing neurites. These data implicate ZFP804A in growth cone function and neurite elongation. The polymorphism rs1344706 lowers expression of ZNF804A during prenatal brain development. This may affect ZNF804A's role in cone function and neurite elongation leading to synaptic deficits and altered neural connectivity.

Three-dimensional evaluation of pharyngeal airway in individuals with varying growth patterns using cone beam computed tomography

OpenAIRE

Rohan Diwakar; Maninder Singh Sidhu; Mona Prabhakar; Seema Grover; Ritu Phogat

2015-01-01

Introduction: The purpose of this study was to evaluate the pharyngeal airway volume in individuals with different vertical growth patterns. Methods: Cone beam computed tomography scans were evaluated of 40 subjects with the age range from 14 to 25 years and were divided into three groups. Horizontal growers consisted of 13 subjects, normal growers consisted of 14 subjects, and the vertical growers consisted of 13 subjects. The pharyngeal airway volume was measured using In Vivo Dental 5.1 so...

Recurrent abnormalities in conifer cones and the evolutionary origins of flower-like structures.

Science.gov (United States)

Rudall, Paula J; Hilton, Jason; Vergara-Silva, Francisco; Bateman, Richard M

2011-03-01

Conifer cones are reproductive structures that are typically of restricted growth and either exclusively pollen-bearing (male) or exclusively ovule-bearing (female). Here, we review two common spontaneous developmental abnormalities of conifer cones: proliferated cones, in which the apex grows vegetatively, and bisexual cones, which possess both male and female structures. Emerging developmental genetic data, combined with evidence from comparative morphology, ontogeny and palaeobotany, provide new insights into the evolution of both cones and flowers, and prompt novel strategies for understanding seed-plant evolution. Copyright © 2010 Elsevier Ltd. All rights reserved.

Application of empowerment theory for CNS practice.

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Carlson-Catalano, J M

1993-11-01

Power is necessary for the clinical nurse specialist (CNS) to successfully conduct objectives of practice in bureaucratic hospital settings. To obtain power, the CNS could use strategies of an empowerment theory to fully operationalize roles in hospitals. This article will discuss how the CNS may be empowered utilizing strategies in four empowering categories. In addition, the many benefits of empowering the CNS are reviewed.

Cone Algorithm of Spinning Vehicles under Dynamic Coning Environment

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Shuang-biao Zhang

2015-01-01

Full Text Available Due to the fact that attitude error of vehicles has an intense trend of divergence when vehicles undergo worsening coning environment, in this paper, the model of dynamic coning environment is derived firstly. Then, through investigation of the effect on Euler attitude algorithm for the equivalency of traditional attitude algorithm, it is found that attitude error is actually the roll angle error including drifting error and oscillating error, which is induced directly by dynamic coning environment and further affects the pitch angle and yaw angle through transferring. Based on definition of the cone frame and cone attitude, a cone algorithm is proposed by rotation relationship to calculate cone attitude, and the relationship between cone attitude and Euler attitude of spinning vehicle is established. Through numerical simulations with different conditions of dynamic coning environment, it is shown that the induced error of Euler attitude fluctuates by the variation of precession and nutation, especially by that of nutation, and the oscillating frequency of roll angle error is twice that of pitch angle error and yaw angle error. In addition, the rotation angle is more competent to describe the spinning process of vehicles under coning environment than Euler angle gamma, and the real pitch angle and yaw angle are calculated finally.

Central Nervous System (CNS Disease Triggering Takotsubo Syndrome

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Josef Finsterer

2016-01-01

Full Text Available Takotsubo syndrome (TTS is usually triggered by psychological or physical stress. One of the many physical sources of stress are central nervous system (CNS disorders. CNS disorders most frequently triggering TTS include subarachnoid bleeding, epilepsy, ischemic stroke, migraine, and intracerebral bleeding. More rare CNS-triggers of TTS include posterior reversible encephalopathy syndrome (PRES, amyotrophic lateral sclerosis, encephalitis, or traumatic brain or spinal cord injury. TTS triggered by any of the CNS disorders needs to be recognized since adequate treatment of TTS may improve the general outcome from the CNS disorder as well. Neurologists need to be aware of TTS as a complication of specific CNS disorders but TTS may be triggered also by CNS disorders so far not recognised as causes of TTS.

Cold knife cone biopsy

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... biopsy; Pap smear - cone biopsy; HPV - cone biopsy; Human papilloma virus - cone biopsy; Cervix - cone biopsy; Colposcopy - cone biopsy Images Female reproductive anatomy Cold cone biopsy Cold cone removal References Baggish ...

microRNAs in CNS disorders

DEFF Research Database (Denmark)

Kocerha, Jannet; Kauppinen, Sakari; Wahlestedt, Claes

2009-01-01

RNAs (miRNAs) have been identified in the mammalian central nervous system (CNS) and are reported to mediate pivotal roles in many aspects of neuronal functions. Disruption of miRNA-based post-transcriptional regulation has been implicated in a range of CNS disorders as one miRNA is predicted to impact...

Supratentorial CNS malformations

International Nuclear Information System (INIS)

Zlatareva, D.

2012-01-01

Full text: Clinical suspicion of a developmental anomaly of the central nervous system (CNS) is a frequent indication for performing and magnetic resonance imaging (MRI) examination of the brain. Classification systems for malformation of the CNS are constantly revised according to newer scientific research. Developmental abnormalities can be classified in two main types. The first category consists of disorders of organogenesis in which genetic defects or any ischemic, metabolic, toxic or infectious insult to the developing brain can cause malformation. These malformations result from abnormal neuronal and glial proliferation and from anomalies of neuronal migration and or cortical organization. They are divided into supra- and infratentorial and may involve grey or white matter or both. The second category of congenital brain abnormalities is disorders of histogenesis which result from abnormal cell differentiation with a relatively normal brain appearance. Supratentorial CNS malformations could be divided into anomalies in telencephalic commissure, holoprosencephalies and malformations in cortical development. There are three main telencephalic commissures: the anterior commissure, the hippocampal commissure and the corpus callosum. Their morphology (hypoplasia, hyperplasia, agenesis, dysgenesis, even atrophy) reflects the development of the brain. Their agenesis, complete or partial, is one of the most commonly observed features in the malformations of the brain and is a part of many syndromes. Malformations of cortical development (MCD) are heterogeneous group of disease which result from disruption of 3 main stages of cortical development. The common clinical presentation is refractory epilepsy and or developmental delay. The most common MCD are heterotopias, focal cortical dysplasia, polymicrogyria, schizencephaly, pachygyria and lizencephaly. The exact knowledge of the brain anatomy and embryology is mandatory to provide a better apprehension of the

Deficiency of the Survival of Motor Neuron Protein Impairs mRNA Localization and Local Translation in the Growth Cone of Motor Neurons.

Science.gov (United States)

Fallini, Claudia; Donlin-Asp, Paul G; Rouanet, Jeremy P; Bassell, Gary J; Rossoll, Wilfried

2016-03-30

Spinal muscular atrophy (SMA) is a neurodegenerative disease primarily affecting spinal motor neurons. It is caused by reduced levels of the survival of motor neuron (SMN) protein, which plays an essential role in the biogenesis of spliceosomal small nuclear ribonucleoproteins in all tissues. The etiology of the specific defects in the motor circuitry in SMA is still unclear, but SMN has also been implicated in mediating the axonal localization of mRNA-protein complexes, which may contribute to the axonal degeneration observed in SMA. Here, we report that SMN deficiency severely disrupts local protein synthesis within neuronal growth cones. We also identify the cytoskeleton-associated growth-associated protein 43 (GAP43) mRNA as a new target of SMN and show that motor neurons from SMA mouse models have reduced levels ofGAP43mRNA and protein in axons and growth cones. Importantly, overexpression of two mRNA-binding proteins, HuD and IMP1, restoresGAP43mRNA and protein levels in growth cones and rescues axon outgrowth defects in SMA neurons. These findings demonstrate that SMN plays an important role in the localization and local translation of mRNAs with important axonal functions and suggest that disruption of this function may contribute to the axonal defects observed in SMA. The motor neuron disease spinal muscular atrophy (SMA) is caused by reduced levels of the survival of motor neuron (SMN) protein, which plays a key role in assembling RNA/protein complexes that are essential for mRNA splicing. It remains unclear whether defects in this well characterized housekeeping function cause the specific degeneration of spinal motor neurons observed in SMA. Here, we describe an additional role of SMN in regulating the axonal localization and local translation of the mRNA encoding growth-associated protein 43 (GAP43). This study supports a model whereby SMN deficiency impedes transport and local translation of mRNAs important for neurite outgrowth and stabilization

New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs.

Science.gov (United States)

Sturm, Dominik; Orr, Brent A; Toprak, Umut H; Hovestadt, Volker; Jones, David T W; Capper, David; Sill, Martin; Buchhalter, Ivo; Northcott, Paul A; Leis, Irina; Ryzhova, Marina; Koelsche, Christian; Pfaff, Elke; Allen, Sariah J; Balasubramanian, Gnanaprakash; Worst, Barbara C; Pajtler, Kristian W; Brabetz, Sebastian; Johann, Pascal D; Sahm, Felix; Reimand, Jüri; Mackay, Alan; Carvalho, Diana M; Remke, Marc; Phillips, Joanna J; Perry, Arie; Cowdrey, Cynthia; Drissi, Rachid; Fouladi, Maryam; Giangaspero, Felice; Łastowska, Maria; Grajkowska, Wiesława; Scheurlen, Wolfram; Pietsch, Torsten; Hagel, Christian; Gojo, Johannes; Lötsch, Daniela; Berger, Walter; Slavc, Irene; Haberler, Christine; Jouvet, Anne; Holm, Stefan; Hofer, Silvia; Prinz, Marco; Keohane, Catherine; Fried, Iris; Mawrin, Christian; Scheie, David; Mobley, Bret C; Schniederjan, Matthew J; Santi, Mariarita; Buccoliero, Anna M; Dahiya, Sonika; Kramm, Christof M; von Bueren, André O; von Hoff, Katja; Rutkowski, Stefan; Herold-Mende, Christel; Frühwald, Michael C; Milde, Till; Hasselblatt, Martin; Wesseling, Pieter; Rößler, Jochen; Schüller, Ulrich; Ebinger, Martin; Schittenhelm, Jens; Frank, Stephan; Grobholz, Rainer; Vajtai, Istvan; Hans, Volkmar; Schneppenheim, Reinhard; Zitterbart, Karel; Collins, V Peter; Aronica, Eleonora; Varlet, Pascale; Puget, Stephanie; Dufour, Christelle; Grill, Jacques; Figarella-Branger, Dominique; Wolter, Marietta; Schuhmann, Martin U; Shalaby, Tarek; Grotzer, Michael; van Meter, Timothy; Monoranu, Camelia-Maria; Felsberg, Jörg; Reifenberger, Guido; Snuderl, Matija; Forrester, Lynn Ann; Koster, Jan; Versteeg, Rogier; Volckmann, Richard; van Sluis, Peter; Wolf, Stephan; Mikkelsen, Tom; Gajjar, Amar; Aldape, Kenneth; Moore, Andrew S; Taylor, Michael D; Jones, Chris; Jabado, Nada; Karajannis, Matthias A; Eils, Roland; Schlesner, Matthias; Lichter, Peter; von Deimling, Andreas; Pfister, Stefan M; Ellison, David W; Korshunov, Andrey; Kool, Marcel

2016-02-25

Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of institutionally diagnosed CNS-PNETs display molecular profiles indistinguishable from those of various other well-defined CNS tumor entities, facilitating diagnosis and appropriate therapy for patients with these tumors. From the remaining fraction of CNS-PNETs, we identify four new CNS tumor entities, each associated with a recurrent genetic alteration and distinct histopathological and clinical features. These new molecular entities, designated "CNS neuroblastoma with FOXR2 activation (CNS NB-FOXR2)," "CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT-CIC)," "CNS high-grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1)," and "CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR)," will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by poorly differentiated CNS tumors. Copyright © 2016 Elsevier Inc. All rights reserved.

A safety assessment methodology applied to CNS/ATM-based air traffic control system

Energy Technology Data Exchange (ETDEWEB)

Vismari, Lucio Flavio, E-mail: lucio.vismari@usp.b [Safety Analysis Group (GAS), School of Engineering at University of Sao Paulo (Poli-USP), Av. Prof. Luciano Gualberto, Trav.3, n.158, Predio da Engenharia de Eletricidade, Sala C2-32, CEP 05508-900, Sao Paulo (Brazil); Batista Camargo Junior, Joao, E-mail: joaocamargo@usp.b [Safety Analysis Group (GAS), School of Engineering at University of Sao Paulo (Poli-USP), Av. Prof. Luciano Gualberto, Trav.3, n.158, Predio da Engenharia de Eletricidade, Sala C2-32, CEP 05508-900, Sao Paulo (Brazil)

2011-07-15

In the last decades, the air traffic system has been changing to adapt itself to new social demands, mainly the safe growth of worldwide traffic capacity. Those changes are ruled by the Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) paradigm , based on digital communication technologies (mainly satellites) as a way of improving communication, surveillance, navigation and air traffic management services. However, CNS/ATM poses new challenges and needs, mainly related to the safety assessment process. In face of these new challenges, and considering the main characteristics of the CNS/ATM, a methodology is proposed at this work by combining 'absolute' and 'relative' safety assessment methods adopted by the International Civil Aviation Organization (ICAO) in ICAO Doc.9689 , using Fluid Stochastic Petri Nets (FSPN) as the modeling formalism, and compares the safety metrics estimated from the simulation of both the proposed (in analysis) and the legacy system models. To demonstrate its usefulness, the proposed methodology was applied to the 'Automatic Dependent Surveillance-Broadcasting' (ADS-B) based air traffic control system. As conclusions, the proposed methodology assured to assess CNS/ATM system safety properties, in which FSPN formalism provides important modeling capabilities, and discrete event simulation allowing the estimation of the desired safety metric.

A safety assessment methodology applied to CNS/ATM-based air traffic control system

International Nuclear Information System (INIS)

Vismari, Lucio Flavio; Batista Camargo Junior, Joao

2011-01-01

In the last decades, the air traffic system has been changing to adapt itself to new social demands, mainly the safe growth of worldwide traffic capacity. Those changes are ruled by the Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) paradigm , based on digital communication technologies (mainly satellites) as a way of improving communication, surveillance, navigation and air traffic management services. However, CNS/ATM poses new challenges and needs, mainly related to the safety assessment process. In face of these new challenges, and considering the main characteristics of the CNS/ATM, a methodology is proposed at this work by combining 'absolute' and 'relative' safety assessment methods adopted by the International Civil Aviation Organization (ICAO) in ICAO Doc.9689 , using Fluid Stochastic Petri Nets (FSPN) as the modeling formalism, and compares the safety metrics estimated from the simulation of both the proposed (in analysis) and the legacy system models. To demonstrate its usefulness, the proposed methodology was applied to the 'Automatic Dependent Surveillance-Broadcasting' (ADS-B) based air traffic control system. As conclusions, the proposed methodology assured to assess CNS/ATM system safety properties, in which FSPN formalism provides important modeling capabilities, and discrete event simulation allowing the estimation of the desired safety metric.

SINS/CNS Nonlinear Integrated Navigation Algorithm for Hypersonic Vehicle

Directory of Open Access Journals (Sweden)

Yong-jun Yu

2015-01-01

Full Text Available Celestial Navigation System (CNS has characteristics of accurate orientation and strong autonomy and has been widely used in Hypersonic Vehicle. Since the CNS location and orientation mainly depend upon the inertial reference that contains errors caused by gyro drifts and other error factors, traditional Strap-down Inertial Navigation System (SINS/CNS positioning algorithm setting the position error between SINS and CNS as measurement is not effective. The model of altitude azimuth, platform error angles, and horizontal position is designed, and the SINS/CNS tightly integrated algorithm is designed, in which CNS altitude azimuth is set as measurement information. GPF (Gaussian particle filter is introduced to solve the problem of nonlinear filtering. The results of simulation show that the precision of SINS/CNS algorithm which reaches 130 m using three stars is improved effectively.

Analysis of perfusion weighted image of CNS lymphoma

International Nuclear Information System (INIS)

Lee, In Ho; Kim, Sung Tae; Kim, Hyung-Jin; Kim, Keon Ha; Jeon, Pyoung; Byun, Hong Sik

2010-01-01

Purpose: It is difficult to differentiate CNS lymphoma from other tumors such as malignant gliomas, metastases, or meningiomas with conventional MR imaging, because the imaging findings are overlapped between these tumors. The purpose of this study is to investigate the perfusion weighted MR imaging findings of CNS lymphomas and to compare the relative cerebral blood volume ratios between CNS lymphomas and other tumors such as high grade gliomas, metastases, or meningiomas. Materials and methods: We retrospectively reviewed MRI findings and clinical records in 13 patients with pathologically proven CNS lymphoma between January 2006 and November 2008. We evaluated the relative cerebral blood volume ratios of tumor, which were obtained by dividing the values obtained from the normal white matter on MRI. Results: Total 13 patients (M:F = 8:5; age range 46-67 years, mean age 52.3 years) were included. The CNS lymphomas showed relatively low values of maximum relative CBV ratio in most patients regardless of primary or secondary CNS lymphoma. Conclusion: Perfusion weighted image may be helpful in the diagnosis of CNS lymphoma in spite of primary or secondary or B cell or T cell.

Nerve growth factor stimulates axon outgrowth through negative regulation of growth cone actomyosin restraint of microtubule advance.

Science.gov (United States)

Turney, Stephen G; Ahmed, Mostafa; Chandrasekar, Indra; Wysolmerski, Robert B; Goeckeler, Zoe M; Rioux, Robert M; Whitesides, George M; Bridgman, Paul C

2016-02-01

Nerve growth factor (NGF) promotes growth, differentiation, and survival of sensory neurons in the mammalian nervous system. Little is known about how NGF elicits faster axon outgrowth or how growth cones integrate and transform signal input to motor output. Using cultured mouse dorsal root ganglion neurons, we found that myosin II (MII) is required for NGF to stimulate faster axon outgrowth. From experiments inducing loss or gain of function of MII, specific MII isoforms, and vinculin-dependent adhesion-cytoskeletal coupling, we determined that NGF causes decreased vinculin-dependent actomyosin restraint of microtubule advance. Inhibition of MII blocked NGF stimulation, indicating the central role of restraint in directed outgrowth. The restraint consists of myosin IIB- and IIA-dependent processes: retrograde actin network flow and transverse actin bundling, respectively. The processes differentially contribute on laminin-1 and fibronectin due to selective actin tethering to adhesions. On laminin-1, NGF induced greater vinculin-dependent adhesion-cytoskeletal coupling, which slowed retrograde actin network flow (i.e., it regulated the molecular clutch). On fibronectin, NGF caused inactivation of myosin IIA, which negatively regulated actin bundling. On both substrates, the result was the same: NGF-induced weakening of MII-dependent restraint led to dynamic microtubules entering the actin-rich periphery more frequently, giving rise to faster elongation. © 2016 Turney et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

ZnO twin-cones: synthesis, photoluminescence, and catalytic decomposition of ammonium perchlorate.

Science.gov (United States)

Sun, Xuefei; Qiu, Xiaoqing; Li, Liping; Li, Guangshe

2008-05-19

ZnO twin-cones, a new member to the ZnO family, were prepared directly by a solvothermal method using a mixed solution of zinc nitrate and ethanol. The reaction and growth mechanisms of ZnO twin-cones were investigated by X-ray diffraction, UV-visible spectra, infrared and ion trap mass spectra, and transmission electron microscopy. All as-prepared ZnO cones consisted of tiny single crystals with lengths of several micrometers. With prolonging of the reaction time from 1.5 h to 7 days, the twin-cone shape did not change at all, while the lattice parameters increased slightly and the emission peak of photoluminescence shifted from the green region to the near orange region. ZnO twin-cones are also explored as an additive to promote the thermal decomposition of ammonium perchlorate. The variations of photoluminescence spectra and catalytic roles in ammonium perchlorate decomposition were discussed in terms of the defect structure of ZnO twin-cones.

The Extracellular Environment of the CNS: Influence on Plasticity, Sprouting, and Axonal Regeneration after Spinal Cord Injury

Science.gov (United States)

Forbes, Lindsey H.

2018-01-01

The extracellular environment of the central nervous system (CNS) becomes highly structured and organized as the nervous system matures. The extracellular space of the CNS along with its subdomains plays a crucial role in the function and stability of the CNS. In this review, we have focused on two components of the neuronal extracellular environment, which are important in regulating CNS plasticity including the extracellular matrix (ECM) and myelin. The ECM consists of chondroitin sulfate proteoglycans (CSPGs) and tenascins, which are organized into unique structures called perineuronal nets (PNNs). PNNs associate with the neuronal cell body and proximal dendrites of predominantly parvalbumin-positive interneurons, forming a robust lattice-like structure. These developmentally regulated structures are maintained in the adult CNS and enhance synaptic stability. After injury, however, CSPGs and tenascins contribute to the structure of the inhibitory glial scar, which actively prevents axonal regeneration. Myelin sheaths and mature adult oligodendrocytes, despite their important role in signal conduction in mature CNS axons, contribute to the inhibitory environment existing after injury. As such, unlike the peripheral nervous system, the CNS is unable to revert to a “developmental state” to aid neuronal repair. Modulation of these external factors, however, has been shown to promote growth, regeneration, and functional plasticity after injury. This review will highlight some of the factors that contribute to or prevent plasticity, sprouting, and axonal regeneration after spinal cord injury. PMID:29849554

An invertebrate model for CNS drug discovery

DEFF Research Database (Denmark)

Al-Qadi, Sonia; Schiøtt, Morten; Hansen, Steen Honoré

2015-01-01

BACKGROUND: ABC efflux transporters at the blood brain barrier (BBB), namely the P-glycoprotein (P-gp), restrain the development of central nervous system (CNS) drugs. Consequently, early screening of CNS drug candidates is pivotal to identify those affected by efflux activity. Therefore, simple,...... barriers. CONCLUSION: Findings suggest a conserved mechanism of brain efflux activity between insects and vertebrates, confirming that this model holds promise for inexpensive and high-throughput screening relative to in vivo models, for CNS drug discovery....

Geomorphometric variability of "monogenetic" volcanic cones: Evidence from Mauna Kea, Lanzarote and experimental cones

Science.gov (United States)

Kervyn, M.; Ernst, G. G. J.; Carracedo, J.-C.; Jacobs, P.

2012-01-01

Volcanic cones are the most common volcanic constructs on Earth. Their shape can be quantified using two morphometric ratios: the crater/cone base ratio (W cr/W co) and the cone height/width ratio (H co/W co). The average values for these ratios obtained over entire cone fields have been explained by the repose angle of loose granular material (i.e. scoria) controlling cone slopes. The observed variability in these ratios between individual cones has been attributed to the effect of erosional processes or contrasting eruptive conditions on cone morphometry. Using a GIS-based approach, high spatial resolution Digital Elevation Models and airphotos, two new geomorphometry datasets for cone fields at Mauna Kea (Hawaii, USA) and Lanzarote (Canary Islands, Spain) are extracted and analyzed here. The key observation in these datasets is the great variability in morphometric ratios, even for simple-shape and well-preserved cones. Simple analog experiments are presented to analyze factors influencing the morphometric ratios. The formation of a crater is simulated within an analog cone (i.e. a sand pile) by opening a drainage conduit at the cone base. Results from experiments show that variability in the morphometric ratios can be attributed to variations in the width, height and horizontal offset of the drainage point relative to the cone symmetry axis, to the dip of the underlying slope or to the influence of a small proportion of fine cohesive material. GIS analysis and analog experiments, together with specific examples of cones documented in the field, suggest that the morphometric ratios for well-preserved volcanic cones are controlled by a combination of 1) the intrinsic cone material properties, 2) time-dependent eruption conditions, 3) the local setting, and 4) the method used to estimate the cone height. Implications for interpreting cone morphometry solely as either an age or as an eruption condition indicator are highlighted.

New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs

DEFF Research Database (Denmark)

Sturm, Dominik; Orr, Brent A; Toprak, Umut H

2016-01-01

with a recurrent genetic alteration and distinct histopathological and clinical features. These new molecular entities, designated "CNS neuroblastoma with FOXR2 activation (CNS NB-FOXR2)," "CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT-CIC)," "CNS high-grade neuroepithelial tumor with MN1 alteration...

Foveal cone spacing and cone photopigment density difference: objective measurements in the same subjects.

Science.gov (United States)

Marcos, S; Tornow, R P; Elsner, A E; Navarro, R

1997-07-01

Foveal cone spacing was measured in vivo using an objective technique: ocular speckle interferometry. Cone packing density was computed from cone spacing data. Foveal cone photopigment density difference was measured in the same subjects using retinal densitometry with a scanning laser ophthalmoscope. Both the cone packing density and cone photopigment density difference decreased sharply with increasing retinal eccentricity. From the comparison of both sets of measurements, the computed amounts of photopigment per cone increased slightly with increasing retinal eccentricity. Consistent with previous results, decreases in cone outer segment length are over-compensated by an increase in the outer segment area, at least in retinal eccentricities up to 1 deg.

CNS infections in immunocompetent patients

International Nuclear Information System (INIS)

Hartmann, K.M.; Zimmer, A.; Reith, W.

2008-01-01

This article gives a review of the most frequent infective agents reasonable for CNS infections in immunocompetent patients as well as their localisation and imaging specifications. MRI scanning is the gold standard to detect inflammatory conditions in the CNS. Imaging can be normal or nonspecifically altered although the infection is culturally or bioptically proven. There are no pathognomonic, pathogen-specific imaging criteria. The localization and dimension of the inflammation depends on the infection pathway. (orig.) [de

Bovine-associated CNS species resist phagocytosis differently

Science.gov (United States)

2013-01-01

Background Coagulase-negative staphylococci (CNS) cause usually subclinical or mild clinical bovine mastitis, which often remains persistent. Symptoms are usually mild, mostly only comprising slight changes in the appearance of milk and possibly slight swelling. However, clinical mastitis with severe signs has also been reported. The reasons for the differences in clinical expression are largely unknown. Macrophages play an important role in the innate immunity of the udder. This study examined phagocytosis and killing by mouse macrophage cells of three CNS species: Staphylococcus chromogenes (15 isolates), Staphylococcus agnetis (6 isolates) and Staphylococcus simulans (15 isolates). Staphylococcus aureus (7 isolates) was also included as a control. Results All the studied CNS species were phagocytosed by macrophages, but S. simulans resisted phagocytosis more effectively than the other CNS species. Only S. chromogenes was substantially killed by macrophages. Significant variations between isolates were seen in both phagocytosis and killing by macrophages and were more common in the killing assays. Significant differences between single CNS species and S. aureus were observed in both assays. Conclusion This study demonstrated that differences in the phagocytosis and killing of mastitis-causing staphylococci by macrophages exist at both the species and isolate level. PMID:24207012

Selective rab11 transport and the intrinsic regenerative ability of CNS axons

Czech Academy of Sciences Publication Activity Database

Koseki, H.; Donegá, M.; Lam, B.Y.H.; Petrová, V.; van Erp, S.; Yeo, G.S.H.; Kwok, Jessica; Ffrench-Constant, Ch.; Eva, R.; Fawcett, James

2017-01-01

Roč. 6, aug (2017), e26956 ISSN 2050-084X R&D Projects: GA MŠk(CZ) EF15_003/0000419 Institutional support: RVO:68378041 Keywords : spinal-cord-injury * chondroitin sulfate proteoglycans * growth cone Subject RIV: FH - Neurology OBOR OECD: Neuroscience s (including psychophysiology Impact factor: 7.725, year: 2016

Quotient normed cones

Indian Academy of Sciences (India)

general setting of the space CL(X, Y ) of all continuous linear mappings from a normed cone (X, p) to a normed cone (Y, q), extending several well-known results related to open continuous linear mappings between normed linear spaces. Keywords. Normed cone; extended quasi-metric; continuous linear mapping; bicom-.

Fundamental harmonic electron cyclotron emission for hot, loss-cone type distributions

International Nuclear Information System (INIS)

Bornatici, M.; Ruffina, U.; Westerhof, E.

1988-01-01

Electron cyclotron emission (ECE) is an important diagnostic tool for the study of hot plasmas. ECE can be used not only to measure the electron temperature but also to obtain information about non-thermal characteristics of the electron distribution function. One such a nonthermal characteristic is a loss-cone anisotropy. Loss-cone anisotropy can give rise to unstable growth of electro-magnetic waves around the harmonics of the electron cyclotron resonance and to increased emissivity of electron cyclotron waves. In case of high electron temperatures, also the dispersion properties of the extraordinary (X-) mode arond the fundamental electron cyclotron resonance are changed due to loss-cone anisotropy. The consequences of these dispersion properties for the emissivity of the fundamental harmonic X-mode are analyzed for perpendicular propagation. The emissivity, is calculated for two types of distribution functions having a loss-cone anisotropy. These distribution functions are a relativistic Dory-Guest-Harris type distribution function and modified relativistic Maxwellian distribution having a loss-cone with rounded edges (author). 9 refs.; 2 figs

CNS embryonal tumours: WHO 2016 and beyond.

Science.gov (United States)

Pickles, J C; Hawkins, C; Pietsch, T; Jacques, T S

2018-02-01

Embryonal tumours of the central nervous system (CNS) present a significant clinical challenge. Many of these neoplasms affect young children, have a very high mortality and therapeutic strategies are often aggressive with poor long-term outcomes. There is a great need to accurately diagnose embryonal tumours, predict their outcome and adapt therapy to the individual patient's risk. For the first time in 2016, the WHO classification took into account molecular characteristics for the diagnosis of CNS tumours. This integration of histological features with genetic information has significantly changed the diagnostic work-up and reporting of tumours of the CNS. However, this remains challenging in embryonal tumours due to their previously unaccounted tumour heterogeneity. We describe the recent revisions made to the 4th edition of the WHO classification of CNS tumours and review the main changes, while highlighting some of the more common diagnostic testing strategies. © 2017 British Neuropathological Society.

Innate Interferons Regulate CNS Inflammation

DEFF Research Database (Denmark)

Dieu, Ruthe; Khorooshi, Reza M. H.; Mariboe, Anne

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) whose pathology is characterised by demyelination and axonal damage. This results from interplay between CNS-resident glia, infiltrating leukocytes and a plethora of cytokines and chemokines. Currently...... potential IFN-inducing receptor that signals through NF-kB. Receptor activator of NF-kB (RANK) belongs to the TNF-receptor superfamily and has been shown to induce IFN-beta in medullary thymic epithelial cells affecting autoimmune regulatory processes and osteoclast precursor cells in association to bone...

Air pollution: mechanisms of neuroinflammation and CNS disease.

Science.gov (United States)

Block, Michelle L; Calderón-Garcidueñas, Lilian

2009-09-01

Air pollution has been implicated as a chronic source of neuroinflammation and reactive oxygen species (ROS) that produce neuropathology and central nervous system (CNS) disease. Stroke incidence and Alzheimer's and Parkinson's disease pathology are linked to air pollution. Recent reports reveal that air pollution components reach the brain; systemic effects that impact lung and cardiovascular disease also impinge upon CNS health. While mechanisms driving air pollution-induced CNS pathology are poorly understood, new evidence suggests that microglial activation and changes in the blood-brain barrier are key components. Here we summarize recent findings detailing the mechanisms through which air pollution reaches the brain and activates the resident innate immune response to become a chronic source of pro-inflammatory factors and ROS, culminating in CNS disease.

Effects of early cone collection and artificial ripening on white spruce and red pine germination

Energy Technology Data Exchange (ETDEWEB)

Winston, D.A.; Haddon, B.D.

1981-12-01

Two experiments were conducted at the Petawawa National Forestry Institute. Chalk River, Ontario in 1978 to test the feasibility of early cone collection and to determine the optimum conditions for the artificial ripening of white spruce and red pine cones. Cones were collected at periodic intervals, commencing 7 weeks before natural cone ripeness, and stored under four storage conditions and three storage periods. White spruce cones collected August 1, 4 weeks before natural seed dispersal, and stored on open, screened trays for 12 weeks at 5 degrees Celcius and 75-95% relative humidity yielded seeds of high germinability. Seeds extracted from cones immediately after this collection failed to germinate. Cold storage of white spruce cones at 5 degrees Celcius for as little as 4 weeks eliminated dormancy and the subsequent need for seed stratification after extraction. Good germination of red pine seeds was obtained from cones collected August 16, 7 weeks before natural seed dispersal, and stored on screened trays in a well-ventilated, unheated building, for 4 weeks. Completion of embryo growth must be attained before artificial ripening can be successfully applied; it may be used as an index for commencement of cone collections provided subsequent cone handling includes artificial ripening. (Refs. 39).

Berkeley Lighting Cone

Energy Technology Data Exchange (ETDEWEB)

Lask, Kathleen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gadgil, Ashok [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2016-10-24

A lighting cone is a simple metal cone placed on the fuel bed of a stove during ignition to act as a chimney, increasing the draft through the fuel bed. Many stoves tend to be difficult to light due to poor draft through the fuel bed, so lighting cones are used in various parts of the world as an inexpensive accessory to help with ignition.

CNS adverse events associated with antimalarial agents. Fact or fiction?

NARCIS (Netherlands)

Phillips-Howard, P. A.; ter Kuile, F. O.

1995-01-01

CNS adverse drug events are dramatic, and case reports have influenced clinical opinion on the use of antimalarials. Malaria also causes CNS symptoms, thus establishing causality is difficult. CNS events are associated with the quinoline and artemisinin derivatives. Chloroquine, once considered too

Progress in light cone physics

International Nuclear Information System (INIS)

Preparata, G.

1973-01-01

A very brief review is given of the progress made in the physics of the light cone in the past year. Included are the light cone expansion, gauge invariance and the consequences of precocious scaling near threshold, the light cone description of the muon pair experiment, light cone expansions, and the assessment and exploitation of analyticity properties in both mass and energy of light cone amplitudes. (U.S.)

Ejecta evolution during cone impact

KAUST Repository

Marston, Jeremy

2014-07-07

We present findings from an experimental investigation into the impact of solid cone-shaped bodies onto liquid pools. Using a variety of cone angles and liquid physical properties, we show that the ejecta formed during the impact exhibits self-similarity for all impact speeds for very low surface tension liquids, whilst for high-surface tension liquids similarity is only achieved at high impact speeds. We find that the ejecta tip can detach from the cone and that this phenomenon can be attributed to the air entrainment phenomenon. We analyse of a range of cone angles, including some ogive cones, and impact speeds in terms of the spatiotemporal evolution of the ejecta tip. Using superhydrophobic cones, we also examine the entry of cones which entrain an air layer.

3rd ENRI International Workshop on ATM/CNS

CERN Document Server

2014-01-01

The Electronic Navigation Research Institute (ENRI) held its third　International Workshop on ATM / CNS in 2013 with the theme of "Drafting　the future sky". There is worldwide activity taking place in the research and development　of modern air traffic management (ATM) and its enabling technologies in　Communication, Navigation and Surveillance (CNS). Pioneering work is necessary to contribute to the global harmonization　of air traffic management and control. At this workshop, leading experts　in  research, industry and academia from around the world met to share　their ideas and approaches on ATM/CNS related topics.

CNS penetration of ART in HIV-infected children

NARCIS (Netherlands)

van den Hof, Malon; Blokhuis, Charlotte; Cohen, Sophie; Scherpbier, Henriette J.; Wit, Ferdinand W. N. M.; Pistorius, M. C. M.; Kootstra, Neeltje A.; Teunissen, Charlotte E.; Mathot, Ron A. A.; Pajkrt, Dasja

2018-01-01

Background: Paediatric data on CNS penetration of antiretroviral drugs are scarce. Objectives: To evaluate CNS penetration of antiretroviral drugs in HIV-infected children and explore associations with neurocognitive function. Patients and methods: Antiretroviral drug levels were measured in paired

Correlation Between Cone Penetration Rate And Measured Cone Penetration Parameters In Silty Soils

DEFF Research Database (Denmark)

Poulsen, Rikke; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

2013-01-01

This paper shows, how a change in cone penetration rate affects the cone penetration measurements, hence the cone resistance, pore pressure, and sleeve friction in silty soil. The standard rate of penetration is 20 mm/s, and it is generally accepted that undrained penetration occurs in clay while...... drained penetration occurs in sand. When lowering the penetration rate, the soil pore water starts to dissipate and a change in the drainage condition is seen. In intermediate soils such as silty soils, the standard cone penetration rate may result in a drainage condition that could be undrained......, partially or fully drained. However, lowering the penetration rate in silty soils has a great significance because of the soil permeability, and only a small change in penetration rate will result in changed cone penetration measurements. In this paper, analyses will be done on data from 15 field cone...

Time development of drift wave with loss-cone in an inhomogeneous low β plasma

International Nuclear Information System (INIS)

Pandey, R.P.; Sharan, R.R.; Prasad, Ramesh; Mishra, S.P.; Tiwari, M.S.

1995-01-01

Using particle aspect analysis, a generalized dispersion relation for the time-dependent electrostatic drift waves propagating through inhomogeneous low β magnetoplasma (β being the ratio of plasma pressure to the magnetic pressure) has been derived in the presence of the loss-cone distribution index (J). The dispersion characteristics and time-dependent growth/damping rates of the wave have been computed. The distribution index seems to modify the dispersion characteristics and hence the growth rate. The computed growth rate is time-dependent, increasing with the increase of time, while the growth rate decreases with the increase of the loss-cone distribution index. In the case when growth rate increasing sufficiently with time, becomes comparable to the real frequency of the wave, the present linear theory loses its validity. The applicability of the result for the space plasma has been indicated particularly for the parameters suited to plasmapause region. (author). 30 refs., 5 figs

PEG minocycline-liposomes ameliorate CNS autoimmune disease.

Directory of Open Access Journals (Sweden)

Wei Hu

Full Text Available Minocycline is an oral tetracycline derivative with good bioavailability in the central nervous system (CNS. Minocycline, a potent inhibitor of matrix metalloproteinase (MMP-9, attenuates disease activity in experimental autoimmune encephalomyelitis (EAE, an animal model of multiple sclerosis (MS. Potential adverse effects associated with long-term daily minocycline therapy in human patients are concerning. Here, we investigated whether less frequent treatment with long-circulating polyethylene glycol (PEG minocycline liposomes are effective in treating EAE.Performing in vitro time kinetic studies of PEG minocycline-liposomes in human peripheral blood mononuclear cells (PBMCs, we determined that PEG minocycline-liposome preparations stabilized with CaCl(2 are effective in diminishing MMP-9 activity. Intravenous injections of PEG minocycline-liposomes every five days were as effective in ameliorating clinical EAE as daily intraperitoneal injections of minocycline. Treatment of animals with PEG minocycline-liposomes significantly reduced the number of CNS-infiltrating leukocytes, and the overall expression of MMP-9 in the CNS. There was also a significant suppression of MMP-9 expression and proteolytic activity in splenocytes of treated animals, but not in CNS-infiltrating leukocytes. Thus, leukocytes gaining access to the brain and spinal cord require the same absolute amount of MMP-9 in all treatment groups, but minocycline decreases the absolute cell number.Our data indicate that less frequent injections of PEG minocycline-liposomes are an effective alternative pharmacotherapy to daily minocycline injections for the treatment of CNS autoimmune diseases. Also, inhibition of MMP-9 remains a promising treatment target in EAE and patients with MS.

Val66Met polymorphism of BDNF alters prodomain structure to induce neuronal growth cone retraction.

Science.gov (United States)

Anastasia, Agustin; Deinhardt, Katrin; Chao, Moses V; Will, Nathan E; Irmady, Krithi; Lee, Francis S; Hempstead, Barbara L; Bracken, Clay

2013-01-01

A common single-nucleotide polymorphism (SNP) in the human brain-derived neurotrophic factor (BDNF) gene results in a Val66Met substitution in the BDNF prodomain region. This SNP is associated with alterations in memory and with enhanced risk to develop depression and anxiety disorders in humans. Here we show that the isolated BDNF prodomain is detected in the hippocampus and that it can be secreted from neurons in an activity-dependent manner. Using nuclear magnetic resonance spectroscopy and circular dichroism, we find that the prodomain is intrinsically disordered, and the Val66Met substitution induces structural changes. Surprisingly, application of Met66 (but not Val66) BDNF prodomain induces acute growth cone retraction and a decrease in Rac activity in hippocampal neurons. Expression of p75(NTR) and differential engagement of the Met66 prodomain to the SorCS2 receptor are required for this effect. These results identify the Met66 prodomain as a new active ligand, which modulates neuronal morphology.

Chloride currents in cones modify feedback from horizontal cells to cones in goldfish retina

Science.gov (United States)

Endeman, Duco; Fahrenfort, Iris; Sjoerdsma, Trijntje; Steijaert, Marvin; ten Eikelder, Huub; Kamermans, Maarten

2012-01-01

In neuronal systems, excitation and inhibition must be well balanced to ensure reliable information transfer. The cone/horizontal cell (HC) interaction in the retina is an example of this. Because natural scenes encompass an enormous intensity range both in temporal and spatial domains, the balance between excitation and inhibition in the outer retina needs to be adaptable. How this is achieved is unknown. Using electrophysiological techniques in the isolated retina of the goldfish, it was found that opening Ca2+-dependent Cl− channels in recorded cones reduced the size of feedback responses measured in both cones and HCs. Furthermore, we show that cones express Cl− channels that are gated by GABA released from HCs. Similar to activation of ICl(Ca), opening of these GABA-gated Cl− channels reduced the size of light-induced feedback responses both in cones and HCs. Conversely, application of picrotoxin, a blocker of GABAA and GABAC receptors, had the opposite effect. In addition, reducing GABA release from HCs by blocking GABA transporters also led to an increase in the size of feedback. Because the independent manipulation of Ca2+-dependent Cl− currents in individual cones yielded results comparable to bath-applied GABA, it was concluded that activation of either Cl− current by itself is sufficient to reduce the size of HC feedback. However, additional effects of GABA on outer retinal processing cannot be excluded. These results can be accounted for by an ephaptic feedback model in which a cone Cl− current shunts the current flow in the synaptic cleft. The Ca2+-dependent Cl− current might be essential to set the initial balance between the feedforward and the feedback signals active in the cone HC synapse. It prevents that strong feedback from HCs to cones flood the cone with Ca2+. Modulation of the feedback strength by GABA might play a role during light/dark adaptation, adjusting the amount of negative feedback to the signal to noise ratio of the

Prophylactic CNS therapy in childhood leukemia

International Nuclear Information System (INIS)

Yokoyama, Takashi; Hiyoshi, Yasuhiko; Fujimoto, Takeo

1982-01-01

This study was designed to evaluate the efficacy of CNS-prophylaxis with high-dose methotrexate (MTX). Seventy children with previously untreated acute lymphoblastic leukemia (ALL) entered to this study between July 1978 and December 1980. According to initial white blood count (WBC), they were stratified to induce remission with; vincristine and prednine in low initial WBC ( lt 25,000/mm 3 ) group and these two agents plus adriamycin in high initial WBC ( gt 25,000/mm 3 ) group. After inducing remission, 62 children who achieved CR, received different CNS-prophlaxis; using a regimen of three doses of weekly high-dose MTX (1,000 mg/m 2 ) 6-hour infusion, which was repeated every 12 weeks-Group A (n = 14); high-dose MTX followed by 2400 rad cranial irradiation plus three doses of i.t. MT X-Group B (n = 15), 2400 rad cranial irradiation plus three doses of i.t. MTX-Group C (n = 16), and in 17 patients with high initial WBC, same as in Group A-Group D (n = 17). During an intravenous 6-h infusion of MTX at a dose of 1,000 mg/m 2 , the CSF concentration of MTX rose to 2.3 +- 2.4 x 10 -6 M after initiation of infusion and remained in 10 -7 M level for 48 hours. CNS-leukemia terminated complete remission in one of 14 children in Group A, two of 15 in Group B, two of 16 in Group C and two of 17 in Group D. The cumulative incidence of CNS-leukemia at 20 months calculated by the technique of Kaplan and Meier was 0% i n Group A, 18.1% in Group B, 7.1% in Group C and 50.8% in Group D. There was no statistical difference among Groups A, B and C. These data suggested that CNS-prophylaxis with high-dose intravenous MTX was effective as well as 2400 rad cranial irradiation plus three doses of i.t. MTX in childhood ALL with low initial WBC. (author)

DRG axon elongation and growth cone collapse rate induced by Sema3A are differently dependent on NGF concentration.

Science.gov (United States)

Kaselis, Andrius; Treinys, Rimantas; Vosyliūtė, Rūta; Šatkauskas, Saulius

2014-03-01

Regeneration of embryonic and adult dorsal root ganglion (DRG) sensory axons is highly impeded when they encounter neuronal growth cone-collapsing factor semaphorin3A (Sema3A). On the other hand, increasing evidence shows that DRG axon's regeneration can be stimulated by nerve growth factor (NGF). In this study, we aimed to evaluate whether increased NGF concentrations can counterweight Sema3A-induced inhibitory responses in 15-day-old mouse embryo (E15) DRG axons. The DRG explants were grown in Neurobasal-based medium with different NGF concentrations ranging from 0 to 100 ng/mL and then treated with Sema3A at constant 10 ng/mL concentration. To evaluate interplay between NGF and Sema3A number of DRG axons, axon outgrowth distance and collapse rate were measured. We found that the increased NGF concentrations abolish Sema3A-induced inhibitory effect on axon outgrowth, while they have no effect on Sema3A-induced collapse rate.

A longitudinal study of growth and growth hormone secretion in children during treatment for acute lymphoblastic leukemia

International Nuclear Information System (INIS)

Marky, I.; Mellander, L.; Lannering, B.; Albertsson-Wikland, K.

1991-01-01

Diminished growth rate during treatment for acute lymphoblastic leukemia (ALL) is of the multifactorial etiology. Effects on GH secretion have been shown after discontinuation of treatment including prophylactic CNS irradiation. Seventeen children treated for ALL with three different CNS preventive schedules were followed longitudinally with repeated estimations of the spontaneous GH secretion during a 24-month period. No difference was found in GH secretion during this time between patients who had received no radiotherapy and those who had received 18 or 24 Gy as CNS prophylaxis. During dexamethasone treatment the GH secretion was completely suppressed, which can be a mediator for the diminished growth rate during the first 2 years of ALL treatment. We conclude that there is no clinical reason to perform GH analysis within the first 24 months of treatment for ALL

Critical condition for the transformation from Taylor cone to cone-jet

International Nuclear Information System (INIS)

Wei Cheng; Zhao Yang; Gang Tie-Qiang; Chen Li-Jie

2014-01-01

An energy method is proposed to investigate the critical transformation condition from a Taylor cone to a cone-jet. Based on the kinetic theorem, the system power allocation and the electrohydrodynamics stability are discussed. The numerical results indicate that the energy of the liquid cone tip experiences a maximum value during the transformation. With the proposed jetting energy, we give the critical transformation condition under which the derivative of jetting energy with respect to the surface area is greater than or equal to the energy required to form a unit of new liquid surface

Review on resonance cone fields

International Nuclear Information System (INIS)

Ohnuma, Toshiro.

1980-02-01

Resonance cone fields and lower hybrid heating are reviewed in this report. The resonance cone fields were reported by Fisher and Gould, and they proposed the use of the measurement of resonance cones and structure as a diagnostic tool to determine the plasma density and electron temperature in magnetoplasma. After the resonance cone, a wave-like disturbance persists. Ohnuma et al. have measured bending, reflection and ducting of resonance cones in detail. The thermal modes in inhomogeneous magnetoplasma were seen. The reflection of thermal mode near an electron plasma frequency layer and an insulating plate has been observed. The non-linear effects of resonance cones is reported. Monochromatic electron beam produces the noise of broad band whistler mode. Lower hybrid waves have been the subject of propagation from the edge of plasma to the lower hybrid layer. Linear lower hybrid waves were studied. The lower hybrid and ion acoustic waves radiated from a point source were observed. The parametric decay of finite-extent, cold electron plasma waves was studied. The lower hybrid cone radiated from a point source going along magnetic field lines was observed. Several experimental data on the lower hybrid heating in tokamak devices have been reported. The theories on resonance cones and lower hybrid waves are introduced in this report. (Kato, T.)

Understanding the cone scale in Cupressaceae: insights from seed-cone teratology in Glyptostrobus pensilis.

Science.gov (United States)

Dörken, Veit Martin; Rudall, Paula J

2018-01-01

Both wild-type and teratological seed cones are described in the monoecious conifer Glyptostrobus pensilis and compared with those of other Cupressaceae sensu lato and other conifers. Some Cupressaceae apparently possess a proliferation of axillary structures in their cone scales. In our interpretation, in Glyptostrobus each bract of both typical and atypical seed cones bears two descending accessory shoots, interpreted here as seed scales (ovuliferous scales). The primary seed scale is fertile and forms the ovules, the second is sterile and forms characteristic tooth-like structures. The bract and the two axillary seed scales are each supplied with a single distinct vascular bundle that enters the cone axis as a separate strand; this vasculature also characterises the descending accessory short shoots in the vegetative parts of the crown. In wild-type seed cones, the fertile seed scale is reduced to its ovules, and the ovules are always axillary. In contrast, the ovules of some of the teratological seed cones examined were located at the centre of the cone scale. An additional tissue found on the upper surface of the sterile lower seed scale is here interpreted as the axis of the fertile seed scale. Thus, the central position of the ovules can be explained by recaulescent fusion of the upper fertile and lower sterile seed scales. In several teratological cone scales, the ovules were enveloped by an additional sterile tissue that is uniseriate and represents an epidermal outgrowth of the fertile seed scale. Close to the ovules, the epidermis was detached from lower tissue and surrounded the ovule completely, except at the micropyle. These teratological features are potentially significant in understanding seed-cone homologies among extant conifers.

Autoimmune process in CNS under Cs-137 inner irradiation

International Nuclear Information System (INIS)

Lisyany, N.I.; Liubich, L.D.

1996-01-01

Autoimmune hypothesis as to the development of radiation-induced brain injuries stands high among the concepts of the CNS post-radiation damage pathogenesis. To study the changes occurring in a living organism affected by a small-dose radiation due to incorporated radionuclides as well as to create adequate models are of critical importance in the post-Chernobyl period. The effects of chronic small-dose inner radiation on the development of autoimmune responses were evaluated by determining the level of the CNS proteins and protein-induced antibodies to the CNS components. (author)

Cones for dental radiography

Energy Technology Data Exchange (ETDEWEB)

Butler, M J [National Radiological Protection Board, Harwell (UK)

1977-04-01

Dental radiographic techniques are summarized. The advantages and disadvantages of the use of both the conventional plastic pointer cone and the open-ended cylinders or divergent cones favoured both by the ICRP (Protection against Ionizing Radiation from External Sources, Oxford, Pergamon Press, 1973, ICRP Publication 15), and in the Code of Practice for the Protection of Persons against Ionizing Radiation arising from Medical and Dental Use (1972, 3rd edition, London, HMSO) are discussed. The use of the word 'should' in these recommendations to signify a desirable requirement, not an essential one, is noted. This wording is currently of interest both nationally and internationally in relation to regulations, standards and notes for guidance. The National Radiological Protection Board (NRPB) has been reviewing the position, and has concluded that open-ended cones have disadvantages which may sometimes outweigh their advantages. Although open-ended cones are preferable under some circumstances, the recommendation that they should be used ought not to be followed without an understanding of the issues involved. The hazards associated with the use of interchangeable cones are considered. The NRPB now proposes that the requirement for the replacement of pointer cones (for both new and existing equipment) should be withdrawn.

Understanding the cone scale in Cupressaceae: insights from seed-cone teratology in Glyptostrobus pensilis

Directory of Open Access Journals (Sweden)

Veit Martin Dörken

2018-06-01

Full Text Available Both wild-type and teratological seed cones are described in the monoecious conifer Glyptostrobus pensilis and compared with those of other Cupressaceae sensu lato and other conifers. Some Cupressaceae apparently possess a proliferation of axillary structures in their cone scales. In our interpretation, in Glyptostrobus each bract of both typical and atypical seed cones bears two descending accessory shoots, interpreted here as seed scales (ovuliferous scales. The primary seed scale is fertile and forms the ovules, the second is sterile and forms characteristic tooth-like structures. The bract and the two axillary seed scales are each supplied with a single distinct vascular bundle that enters the cone axis as a separate strand; this vasculature also characterises the descending accessory short shoots in the vegetative parts of the crown. In wild-type seed cones, the fertile seed scale is reduced to its ovules, and the ovules are always axillary. In contrast, the ovules of some of the teratological seed cones examined were located at the centre of the cone scale. An additional tissue found on the upper surface of the sterile lower seed scale is here interpreted as the axis of the fertile seed scale. Thus, the central position of the ovules can be explained by recaulescent fusion of the upper fertile and lower sterile seed scales. In several teratological cone scales, the ovules were enveloped by an additional sterile tissue that is uniseriate and represents an epidermal outgrowth of the fertile seed scale. Close to the ovules, the epidermis was detached from lower tissue and surrounded the ovule completely, except at the micropyle. These teratological features are potentially significant in understanding seed-cone homologies among extant conifers.

Epigenetic regulation of axon and dendrite growth

Directory of Open Access Journals (Sweden)

Ephraim F Trakhtenberg

2012-03-01

Full Text Available Neuroregenerative therapies for central nervous system (CNS injury, neurodegenerative disease, or stroke require axons of damaged neurons to grow and reinnervate their targets. However, mature mammalian CNS neurons do not regenerate their axons, limiting recovery in these diseases (Yiu and He, 2006. CNS’ regenerative failure may be attributable to the development of an inhibitory CNS environment by glial-associated inhibitory molecules (Yiu and He, 2006, and by various cell-autonomous factors (Sun and He, 2010. Intrinsic axon growth ability also declines developmentally (Li et al., 1995; Goldberg et al., 2002; Bouslama-Oueghlani et al., 2003; Blackmore and Letourneau, 2006 and is dependent on transcription (Moore et al., 2009. Although neurons’ intrinsic capacity for axon growth may depend in part on the panoply of expressed transcription factors (Moore and Goldberg, 2011, epigenetic factors such as the accessibility of DNA and organization of chromatin are required for downstream genes to be transcribed. Thus a potential approach to overcoming regenerative failure focuses on the epigenetic mechanisms regulating regenerative gene expression in the CNS. Here we review molecular mechanisms regulating the epigenetic state of DNA through chromatin modifications, their implications for regulating axon and dendrite growth, and important new directions for this field of study.

Light-cone quantization of quantum chromodynamics

International Nuclear Information System (INIS)

Brodsky, S.J.; Pauli, H.C.

1991-06-01

We discuss the light-cone quantization of gauge theories from two perspectives: as a calculational tool for representing hadrons as QCD bound-states of relativistic quarks and gluons, and also as a novel method for simulating quantum field theory on a computer. The light-cone Fock state expansion of wavefunctions at fixed light cone time provides a precise definition of the parton model and a general calculus for hadronic matrix elements. We present several new applications of light-cone Fock methods, including calculations of exclusive weak decays of heavy hadrons, and intrinsic heavy-quark contributions to structure functions. A general nonperturbative method for numerically solving quantum field theories, ''discretized light-cone quantization,'' is outlined and applied to several gauge theories, including QCD in one space and one time dimension, and quantum electrodynamics in physical space-time at large coupling strength. The DLCQ method is invariant under the large class of light-cone Lorentz transformations, and it can be formulated such at ultraviolet regularization is independent of the momentum space discretization. Both the bound-state spectrum and the corresponding relativistic light-cone wavefunctions can be obtained by matrix diagonalization and related techniques. We also discuss the construction of the light-cone Fock basis, the structure of the light-cone vacuum, and outline the renormalization techniques required for solving gauge theories within the light-cone Hamiltonian formalism

Light-cone quantization of quantum chromodynamics

Energy Technology Data Exchange (ETDEWEB)

Brodsky, S.J. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Pauli, H.C. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.))

1991-06-01

We discuss the light-cone quantization of gauge theories from two perspectives: as a calculational tool for representing hadrons as QCD bound-states of relativistic quarks and gluons, and also as a novel method for simulating quantum field theory on a computer. The light-cone Fock state expansion of wavefunctions at fixed light cone time provides a precise definition of the parton model and a general calculus for hadronic matrix elements. We present several new applications of light-cone Fock methods, including calculations of exclusive weak decays of heavy hadrons, and intrinsic heavy-quark contributions to structure functions. A general nonperturbative method for numerically solving quantum field theories, discretized light-cone quantization,'' is outlined and applied to several gauge theories, including QCD in one space and one time dimension, and quantum electrodynamics in physical space-time at large coupling strength. The DLCQ method is invariant under the large class of light-cone Lorentz transformations, and it can be formulated such at ultraviolet regularization is independent of the momentum space discretization. Both the bound-state spectrum and the corresponding relativistic light-cone wavefunctions can be obtained by matrix diagonalization and related techniques. We also discuss the construction of the light-cone Fock basis, the structure of the light-cone vacuum, and outline the renormalization techniques required for solving gauge theories within the light-cone Hamiltonian formalism.

Engineering progress of CNS concept in Hanaro

International Nuclear Information System (INIS)

Choi, C.O.; Park, K.N.; Park, S.H.

1997-01-01

The Korea Atomic Energy research Institute (KAERI) strives to provide utilizing facilities on and around the Hanaro reactor in order to activate advanced researches by neutron application. As one of the facilities to be installed, the conceptual design work of CNS was started in 1996 with a project schedule of 5 years so that its installation work can be finished by the year 2000. And the major engineering targets of this CNS facility are established for a minimum physical interference with the present facilities of the Hanaro, a reach-out of very-high-gain factors in the cold neutron flux, a simplicity of the maintenance of the facility, and a safety in the operation of the facility as well as the reactor. For the conceptual design of Hanaro CNS, the experience of utilization and production of cold neutron at WWR-M reactor Gatchina, Russia has been used with that of elaborations for PIK reactor in design for neutron guide systems and instruments. (author)

Sleep disorders in children after treatment for a CNS tumour.

Science.gov (United States)

Verberne, Lisa M; Maurice-Stam, Heleen; Grootenhuis, Martha A; Van Santen, Hanneke M; Schouten-Van Meeteren, Antoinette Y N

2012-08-01

The long-term survival of children with a central nervous system (CNS) tumour is improving. However, they experience late effects, including altered habits and patterns of sleep. We evaluated the presence and type of sleep disorders and daytime sleepiness in these children, and its associations with clinical characteristics and daily performance (fatigue and psychosocial functioning). In a cross-sectional study at the outpatient clinic of the Emma Children's Hospital AMC (February-June 2010), sleep, fatigue and psychosocial functioning were analysed in 31 CNS tumour patients (mean age: 11.8years; 20 boys) and compared with 78 patients treated for a non-CNS malignancy (mean age: 9.7years; 41 boys) and norm data. Questionnaires applied were the Sleep Disorder Scale for Children, the Epworth Sleepiness Scale, the Pediatric Quality of Life Inventory, and the Strengths and Difficulties Questionnaire. Sleeping habits and endocrine deficiencies were assessed with a self-developed questionnaire. Increased somnolence was found in CNS tumour patients compared with those with a non-CNS malignancy (8.8±2.8 versus 7.5±2.7; Psleep. No specific risk factors were identified for a sleep disorder in CNS tumour patients, but their excessive somnolence was correlated with lower fatigue related quality of life (QoL) (r=-0.78, Psleep quality and diminish fatigue. © 2011 European Sleep Research Society.

Prediction of human CNS pharmacokinetics using a physiologically-based pharmacokinetic modeling approach

NARCIS (Netherlands)

Yamamoto, Yumi; Valitalo, Pyry A.; Wong, Yin Cheong; Huntjens, Dymphy R.; Proost, Johannes H.; Vermeulen, An; Krauwinkel, Walter; Beukers, Margot W.; Kokki, Hannu; Kokki, Merja; Danhof, Meindert; van Hasselt, Johan G. C.; de Lange, Elizabeth C. M.

2018-01-01

Knowledge of drug concentration-time profiles at the central nervous system (CNS) target-site is critically important for rational development of CNS targeted drugs. Our aim was to translate a recently published comprehensive CNS physiologically-based pharmacokinetic (PBPK) model from rat to human,

Applications of Genomic Sequencing in Pediatric CNS Tumors.

Science.gov (United States)

Bavle, Abhishek A; Lin, Frank Y; Parsons, D Williams

2016-05-01

Recent advances in genome-scale sequencing methods have resulted in a significant increase in our understanding of the biology of human cancers. When applied to pediatric central nervous system (CNS) tumors, these remarkable technological breakthroughs have facilitated the molecular characterization of multiple tumor types, provided new insights into the genetic basis of these cancers, and prompted innovative strategies that are changing the management paradigm in pediatric neuro-oncology. Genomic tests have begun to affect medical decision making in a number of ways, from delineating histopathologically similar tumor types into distinct molecular subgroups that correlate with clinical characteristics, to guiding the addition of novel therapeutic agents for patients with high-risk or poor-prognosis tumors, or alternatively, reducing treatment intensity for those with a favorable prognosis. Genomic sequencing has also had a significant impact on translational research strategies in pediatric CNS tumors, resulting in wide-ranging applications that have the potential to direct the rational preclinical screening of novel therapeutic agents, shed light on tumor heterogeneity and evolution, and highlight differences (or similarities) between pediatric and adult CNS tumors. Finally, in addition to allowing the identification of somatic (tumor-specific) mutations, the analysis of patient-matched constitutional (germline) DNA has facilitated the detection of pathogenic germline alterations in cancer genes in patients with CNS tumors, with critical implications for genetic counseling and tumor surveillance strategies for children with familial predisposition syndromes. As our understanding of the molecular landscape of pediatric CNS tumors continues to advance, innovative applications of genomic sequencing hold significant promise for further improving the care of children with these cancers.

Therapy of CNS leukemia with intraventricular chemotherapy and low-dose neuraxis radiotherapy

International Nuclear Information System (INIS)

Steinherz, P.; Jereb, B.; Galicich, J.

1985-01-01

Successful treatment of CNS leukemic relapse has been frustrated by frequent local recurrence and eventual marrow relapse. The authors describe the treatment of meningeal leukemia in 39 children with intrathecal remission induction followed by the placement of an Ommaya reservoir to facilitate the administration and distribution of chemotherapeutic agents into the CSF. Six hundred or 900 rad of craniospinal radiation and maintenance intraventricular and intrathecal chemotherapy was then administered. Systemic reinduction therapy was added in the later cases. Sixteen children (41%) experienced no further events, with 17+ months to 13+ years (median, 25 months) follow-up . Eleven patients (28%) had CNS recurrence, nine (23%) bone marrow (BM) relapse, and two (5%) testicular relapse as the next adverse event. The course of patients with first isolated CNS relapse differed from that of the others. Eleven (69%) of 16 patients treated for first isolated CNS relapse are alive and 9 are event free, while only 35% of patients whose CNS relapse occurred simultaneously or after recurrent disease at other sites are alive (P = .04). Seven of 23 in the later group are event free. The difference is due to the increased incidence of BM relapse in the later group (30% v 6%; P = .04). For patients with first isolated CNS relapse, the life-table median CNS remission duration is 42 months. The projected CNS relapse-free survival and event-free survival 8 to 10 years after CNS relapse are 40% and 32%, respectively. Headache, nausea, and emesis of short duration were frequent during therapy. In three patients, the reservoir had to be removed for infection. No patient suffered neurologic deficit related to the reservoir. The therapy described can reduce the CNS relapse rate with manageable toxicity

Bidirectional remodeling of β1-integrin adhesions during chemotropic regulation of nerve growth

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Carlstrom Lucas P

2011-11-01

Full Text Available Abstract Background Chemotropic factors in the extracellular microenvironment guide nerve growth by acting on the growth cone located at the tip of extending axons. Growth cone extension requires the coordination of cytoskeleton-dependent membrane protrusion and dynamic adhesion to the extracellular matrix, yet how chemotropic factors regulate these events remains an outstanding question. We demonstrated previously that the inhibitory factor myelin-associated glycoprotein (MAG triggers endocytic removal of the adhesion receptor β1-integrin from the growth cone surface membrane to negatively remodel substrate adhesions during chemorepulsion. Here, we tested how a neurotrophin might affect integrin adhesions. Results We report that brain-derived neurotropic factor (BDNF positively regulates the formation of substrate adhesions in axonal growth cones during stimulated outgrowth and prevents removal of β1-integrin adhesions by MAG. Treatment of Xenopus spinal neurons with BDNF rapidly triggered β1-integrin clustering and induced the dynamic formation of nascent vinculin-containing adhesion complexes in the growth cone periphery. Both the formation of nascent β1-integrin adhesions and the stimulation of axon extension by BDNF required cytoplasmic calcium ion signaling and integrin activation at the cell surface. Exposure to MAG decreased the number of β1-integrin adhesions in the growth cone during inhibition of axon extension. In contrast, the BDNF-induced adhesions were resistant to negative remodeling by MAG, correlating with the ability of BDNF pretreatment to counteract MAG-inhibition of axon extension. Pre-exposure to MAG prevented the BDNF-induced formation of β1-integrin adhesions and blocked the stimulation of axon extension by BDNF. Conclusions Altogether, these findings demonstrate the neurotrophin-dependent formation of integrin-based adhesions in the growth cone and reveal how a positive regulator of substrate adhesions can block

Classically and alternatively activated bone marrow derived macrophages differ in cytoskeletal functions and migration towards specific CNS cell types

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Dijkstra Christine D

2011-05-01

Full Text Available Abstract Background Macrophages play an important role in neuroinflammatory diseases such as multiple sclerosis (MS and spinal cord injury (SCI, being involved in both damage and repair. The divergent effects of macrophages might be explained by their different activation status: classically activated (CA/M1, pro-inflammatory, macrophages and alternatively activated (AA/M2, growth promoting, macrophages. Little is known about the effect of macrophages with these phenotypes in the central nervous system (CNS and how they influence pathogenesis. The aim of this study was therefore to determine the characteristics of these phenotypically different macrophages in the context of the CNS in an in vitro setting. Results Here we show that bone marrow derived CA and AA macrophages have a distinct migratory capacity towards medium conditioned by various cell types of the CNS. AA macrophages were preferentially attracted by the low weight ( Conclusion In conclusion, since AA macrophages are more motile and are attracted by NCM, they are prone to migrate towards neurons in the CNS. CA macrophages have a lower motility and a stronger adhesion to ECM. In neuroinflammatory diseases the restricted migration and motility of CA macrophages might limit lesion size due to bystander damage.

Cone photoreceptor structure in patients with x-linked cone dysfunction and red-green color vision deficiency

DEFF Research Database (Denmark)

Patterson, Emily J.; Wilk, Melissa; Langlo, Christopher S.

2016-01-01

encoded by exon 4, and two with a novel insertion in exon 2. Foveal cone structure and retinal thickness was disrupted to a variable degree, even among related individuals with the same L/M array. CONCLUSIONS. Our findings provide a direct link between disruption of the cone mosaic and L/ M opsin variants......PURPOSE. Mutations in the coding sequence of the L and M opsin genes are often associated with X-linked cone dysfunction (such as Bornholm Eye Disease, BED), though the exact color vision phenotype associated with these disorders is variable. We examined individuals with L/ M opsin gene mutations...... to clarify the link between color vision deficiency and cone dysfunction.  METHODS. We recruited 17 males for imaging. The thickness and integrity of the photoreceptor layers were evaluated using spectral-domain optical coherence tomography. Cone density was measured using high-resolution images of the cone...

The NLO jet vertex in the small-cone approximation for kt and cone algorithms

International Nuclear Information System (INIS)

Colferai, D.; Niccoli, A.

2015-01-01

We determine the jet vertex for Mueller-Navelet jets and forward jets in the small-cone approximation for two particular choices of jet algoritms: the kt algorithm and the cone algorithm. These choices are motivated by the extensive use of such algorithms in the phenomenology of jets. The differences with the original calculations of the small-cone jet vertex by Ivanov and Papa, which is found to be equivalent to a formerly algorithm proposed by Furman, are shown at both analytic and numerical level, and turn out to be sizeable. A detailed numerical study of the error introduced by the small-cone approximation is also presented, for various observables of phenomenological interest. For values of the jet “radius” R=0.5, the use of the small-cone approximation amounts to an error of about 5% at the level of cross section, while it reduces to less than 2% for ratios of distributions such as those involved in the measure of the azimuthal decorrelation of dijets.

The NLO jet vertex in the small-cone approximation for kt and cone algorithms

Energy Technology Data Exchange (ETDEWEB)

Colferai, D.; Niccoli, A. [Dipartimento di Fisica e Astronomia, Università di Firenze and INFN, Sezione di Firenze, 50019 Sesto Fiorentino (Italy)

2015-04-15

We determine the jet vertex for Mueller-Navelet jets and forward jets in the small-cone approximation for two particular choices of jet algoritms: the kt algorithm and the cone algorithm. These choices are motivated by the extensive use of such algorithms in the phenomenology of jets. The differences with the original calculations of the small-cone jet vertex by Ivanov and Papa, which is found to be equivalent to a formerly algorithm proposed by Furman, are shown at both analytic and numerical level, and turn out to be sizeable. A detailed numerical study of the error introduced by the small-cone approximation is also presented, for various observables of phenomenological interest. For values of the jet “radius” R=0.5, the use of the small-cone approximation amounts to an error of about 5% at the level of cross section, while it reduces to less than 2% for ratios of distributions such as those involved in the measure of the azimuthal decorrelation of dijets.

QCD on the light cone

International Nuclear Information System (INIS)

Brodsky, S.J.

1992-09-01

The quantization of gauge theory at fixed light-cone time τ = t - z/c provides new perspectives for solving non-perturbative problems in quantum chromodynamics. The light-cone Fock state expansion provides both a precise definition of the relativistic wavefunctions of hadrons as bound-states of quarks and gluons and a general calculus for predicting QCD processes at the amplitude level. Applications to exclusive processes and weak decay amplitudes are discussed. The problem of computing the hadronic spectrum and the corresponding light-cone wavefunctions of QCD in one space and one time dimension has been successfully reduced to the diagonalization of a discrete representation of the light-cone Hamiltonian. The problems confronting the solution of gauge theories in 3 + 1 dimensions in the light-cone quantization formalism,, including zero modes and non-perturbative renormalization, are reviewed

NMNAT1 variants cause cone and cone-rod dystrophy.

Science.gov (United States)

Nash, Benjamin M; Symes, Richard; Goel, Himanshu; Dinger, Marcel E; Bennetts, Bruce; Grigg, John R; Jamieson, Robyn V

2018-03-01

Cone and cone-rod dystrophies (CD and CRD, respectively) are degenerative retinal diseases that predominantly affect the cone photoreceptors. The underlying disease gene is not known in approximately 75% of autosomal recessive cases. Variants in NMNAT1 cause a severe, early-onset retinal dystrophy called Leber congenital amaurosis (LCA). We report two patients where clinical phenotyping indicated diagnoses of CD and CRD, respectively. NMNAT1 variants were identified, with Case 1 showing an extremely rare homozygous variant c.[271G > A] p.(Glu91Lys) and Case 2 compound heterozygous variants c.[53 A > G];[769G > A] p.(Asn18Ser);(Glu257Lys). The detailed variant analysis, in combination with the observation of an associated macular atrophy phenotype, indicated that these variants were disease-causing. This report demonstrates that the variants in NMNAT1 may cause CD or CRD associated with macular atrophy. Genetic investigations of the patients with CD or CRD should include NMNAT1 in the genes examined.

A photon-driven micromotor can direct nerve fibre growth

Science.gov (United States)

Wu, Tao; Nieminen, Timo A.; Mohanty, Samarendra; Miotke, Jill; Meyer, Ronald L.; Rubinsztein-Dunlop, Halina; Berns, Michael W.

2012-01-01

Axonal path-finding is important in the development of the nervous system, nerve repair and nerve regeneration. The behaviour of the growth cone at the tip of the growing axon determines the direction of axonal growth and migration. We have developed an optical-based system to control the direction of growth of individual axons (nerve fibres) using laser-driven spinning birefringent spheres. One or two optical traps position birefringent beads adjacent to growth cones of cultured goldfish retinal ganglion cell axons. Circularly polarized light with angular momentum causes the trapped bead to spin. This creates a localized microfluidic flow generating an estimated 0.17 pN shear force against the growth cone that turns in response to the shear. The direction of axonal growth can be precisely manipulated by changing the rotation direction and position of this optically driven micromotor. A physical model estimating the shear force density on the axon is described.

Pharmacokinetic, Pharmacogenetic, and Other Factors Influencing CNS Penetration of Antiretrovirals

Directory of Open Access Journals (Sweden)

Jacinta Nwamaka Nwogu

2016-01-01

Full Text Available Neurological complications associated with the human immunodeficiency virus (HIV are a matter of great concern. While antiretroviral (ARV drugs are the cornerstone of HIV treatment and typically produce neurological benefit, some ARV drugs have limited CNS penetration while others have been associated with neurotoxicity. CNS penetration is a function of several factors including sieving role of blood-brain and blood-CSF barriers and activity of innate drug transporters. Other factors are related to pharmacokinetics and pharmacogenetics of the specific ARV agent or mediated by drug interactions, local inflammation, and blood flow. In this review, we provide an overview of the various factors influencing CNS penetration of ARV drugs with an emphasis on those commonly used in sub-Saharan Africa. We also summarize some key associations between ARV drug penetration, CNS efficacy, and neurotoxicity.

CNS-directed gene therapy for lysosomal storage diseases

OpenAIRE

Sands, Mark S; Haskins, Mark E

2008-01-01

Lysosomal storage diseases (LSDs) are a group of inherited metabolic disorders usually caused by deficient activity of a single lysosomal enzyme. As most lysosomal enzymes are ubiquitously expressed, a deficiency in a single enzyme can affect multiple organ systems, including the central nervous system (CNS). At least 75% of all LSDs have a significant CNS component. Approaches such as bone marrow transplantation (BMT) or enzyme replacement therapy (ERT) can effectively treat the systemic dis...

Genetic models for CNS inflammation

DEFF Research Database (Denmark)

Owens, T; Wekerle, H; Antel, J

2001-01-01

The use of transgenic technology to over-express or prevent expression of genes encoding molecules related to inflammation has allowed direct examination of their role in experimental disease. This article reviews transgenic and knockout models of CNS demyelinating disease, focusing primarily on ...

Bortezomib-related neuropathy may mask CNS relapse in multiple myeloma: A call for diligence.

Science.gov (United States)

Abid, Muhammad Bilal; De Mel, Sanjay; Abid, Muhammad Abbas; Tan, Kong Bing; Chng, Wee Joo

2016-07-02

Neuropathy is a common adverse effect of bortezomib. Isolated central nervous system (CNS) relapse in MM remains exceedingly rare and carries a dismal prognosis. We present an unusual case of bortezomib related neuropathy masking a CNS relapse of MM. A 57-year-old female was diagnosed with standard-risk MM with clinical and cytogenetic features not typically associated with CNS involvement. She was treated with 4 cycles of bortezomib/cyclophosphamide/dexamethasone (VCD) and achieved a VGPR, after which she underwent an autologous stem cell transplant (ASCT) followed by bortezomib maintenance. Six months after ASCT she developed symptoms suggestive of peripheral neuropathy which was attributed to bortezomib. However the symptoms persisted despite discontinuation of bortezomib. Imaging and cerebrospinal fluid analysis subsequently confirmed a CNS relapse. CNS involvement in MM (CNS-MM) is uncommon and is considered an aggressive disease. Recently published literature has reported biomarkers with prognostic potential. However, isolated CNS relapse is even less common; an event which carries a very poor prognosis. Given the heterogeneous neurologic manifestations associated with MM, clinical suspicion may be masked by confounding factors such as bortezomib-based therapy. The disease may further remain incognito if the patient does not exhibit any of the high risk features and biomarkers associated with CNS involvement. In the era of proteasome inhibitor (PtdIns)/immunomodulator (IMID)-based therapy for MM which carries neurologic adverse effects, it is prudent to consider CNS relapse early. This case further highlights the need for more robust biomarkers to predict CNS relapse and use of newer novel agents which demonstrate potential for CNS penetration.

Mach cones in space and laboratory dusty magnetoplasmas

International Nuclear Information System (INIS)

Mamun, A.A.; Shukla, P.K

2004-07-01

We present a rigorous theoretical investigation on the possibility for the formation of Mach cones in both space and laboratory dusty magnetoplasmas. We find the parametric regimes for which different types of Mach cones, such as dust acoustic Mach cones, dust magneto-acoustic Mach cones, oscillonic Mach cones, etc. are formed in space and laboratory dusty magnetoplasmas. We also identify the basic features of such different classes of Mach cones (viz. dust- acoustic, dust magneto-acoustic, oscillonic Mach cones, etc.), and clearly explain how they are relevant to space and laboratory dusty manetoplasmas. (author)

Actuarial risk of isolated CNS involvement in Ewing's sarcoma following prophylactic cranial irradiation and intrathecal methotrexate

International Nuclear Information System (INIS)

Trigg, M.E.; Makuch, R.; Glaubiger, D.

1985-01-01

Records of 154 patients with Ewing's sarcoma treated at the National Cancer Institute were reviewed to assess the incidence and risk of developing isolated central nervous system (CNS) Ewing's sarcoma. Sixty-two of the 154 patients had received CNS irradiation and intrathecal (i.t.) methotrexate as part of their initial therapy to prevent the occurrence of isolated CNS Ewing's sarcoma. The risk of developing isolate CNS Ewing's sarcoma was greatest within the first two years after diagnosis and was approximately 10%. The overall risk of CNS recurrence in the group of patients receiving DNS treatment was similar to the group receiving no therapy directed to the CNS. The occurrence of isolated CNS involvement was not prevented by the use of CNS irradiation and i.t. methotrexate. Because of a lack of efficacy to the CNS irradiation regimen, current treatment regimens do not include therapy directed to CNS

Clinical Course, Genetic Etiology, and Visual Outcome in Cone and Cone-Rod Dystrophy

NARCIS (Netherlands)

Thiadens, Alberta A. H. J.; Phan, T. My Lan; Zekveld-Vroon, Renate C.; Leroy, Bart P.; van den Born, L. Ingeborgh; Hoyng, Carel B.; Klaver, Caroline C. W.; Roosing, Susanne; Pott, Jan-Willem R.; van Schooneveld, Mary J.; van Moll-Ramirez, Norka; van Genderen, Maria M.; Boon, Camiel J. F.; den Hollander, Anneke I.; Bergen, Arthur A. B.; De Baere, Elfride; Cremers, Frans P. M.; Lotery, Andrew J.

Objective: To evaluate the clinical course, genetic etiology, and visual prognosis in patients with cone dystrophy (CD) and cone-rod dystrophy (CRD). Design: Clinic-based, longitudinal, multicenter study. Participants: Consecutive probands with CD (N = 98), CRD (N = 83), and affected relatives (N =

Development and degeneration of cone bipolar cells are independent of cone photoreceptors in a mouse model of retinitis pigmentosa.

Directory of Open Access Journals (Sweden)

Miao Chen

Full Text Available Retinal photoreceptors die during retinal synaptogenesis in a portion of retinal degeneration. Whether cone bipolar cells establish regular retinal mosaics and mature morphologies, and resist degeneration are not completely understood. To explore these issues, we backcrossed a transgenic mouse expressing enhanced green fluorescent protein (EGFP in one subset of cone bipolar cells (type 7 into rd1 mice, a classic mouse model of retinal degeneration, to examine the development and survival of cone bipolar cells in a background of retinal degeneration. Our data revealed that both the development and degeneration of cone bipolar cells are independent of the normal activity of cone photoreceptors. We found that type 7 cone bipolar cells achieved a uniform tiling of the retinal surface and developed normal dendritic and axonal arbors without the influence of cone photoreceptor innervation. On the other hand, degeneration of type 7 cone bipolar cells, contrary to our belief of central-to-peripheral progression, was spatially uniform across the retina independent of the spatiotemporal pattern of cone degeneration. The results have important implications for the design of more effective therapies to restore vision in retinal degeneration.

Design of a trichromatic cone array.

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Patrick Garrigan

2010-02-01

Full Text Available Cones with peak sensitivity to light at long (L, medium (M and short (S wavelengths are unequal in number on the human retina: S cones are rare (<10% while increasing in fraction from center to periphery, and the L/M cone proportions are highly variable between individuals. What optical properties of the eye, and statistical properties of natural scenes, might drive this organization? We found that the spatial-chromatic structure of natural scenes was largely symmetric between the L, M and S sensitivity bands. Given this symmetry, short wavelength attenuation by ocular media gave L/M cones a modest signal-to-noise advantage, which was amplified, especially in the denser central retina, by long-wavelength accommodation of the lens. Meanwhile, total information represented by the cone mosaic remained relatively insensitive to L/M proportions. Thus, the observed cone array design along with a long-wavelength accommodated lens provides a selective advantage: it is maximally informative.

Netrin-1 Confines Rhombic Lip-Derived Neurons to the CNS

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Andrea R. Yung

2018-02-01

Full Text Available During brainstem development, newborn neurons originating from the rhombic lip embark on exceptionally long migrations to generate nuclei important for audition, movement, and respiration. Along the way, this highly motile population passes several cranial nerves yet remains confined to the CNS. We found that Ntn1 accumulates beneath the pial surface separating the CNS from the PNS, with gaps at nerve entry sites. In mice null for Ntn1 or its receptor DCC, hindbrain neurons enter cranial nerves and migrate into the periphery. CNS neurons also escape when Ntn1 is selectively lost from the sub-pial region (SPR, and conversely, expression of Ntn1 throughout the mutant hindbrain can prevent their departure. These findings identify a permissive role for Ntn1 in maintaining the CNS-PNS boundary. We propose that Ntn1 confines rhombic lip-derived neurons by providing a preferred substrate for tangentially migrating neurons in the SPR, preventing their entry into nerve roots.

Cone and Seed Maturation of Southern Pines

Science.gov (United States)

James P. Barnett

1976-01-01

If slightly reduced yields and viability are acceptable, loblolly and slash cone collections can begin 2 to 3 weeks before maturity if the cones are stored before processing. Longleaf(P. palestris Mill.) pine cones should be collected only when mature, as storage decreased germination of seeds from immature cones. Biochemical analyses to determine reducing sugar...

CNS complications of rotavirus gastroenteritis

International Nuclear Information System (INIS)

Volosinova, D.

2010-01-01

Rotavirus infection may be accompanied by serious complications, e.g. disabilities central nervous system (CNS). Theory rotavirus penetration across the blood-brain barrier and subsequent rota-associated convulsions by the 2-year case-history of the patient. Rotavirosis minor gastrointestinal symptoms may lead to erroneous diagnosis. (author)

CNS Involvement in AML Patient Treated with 5-Azacytidine

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Diamantina Vasilatou

2014-01-01

Full Text Available Central nervous system (CNS involvement in acute myeloid leukemia (AML is a rare complication of the disease and is associated with poor prognosis. Sometimes the clinical presentation can be unspecific and the diagnosis can be very challenging. Here we report a case of CNS infiltration in a patient suffering from AML who presented with normal complete blood count and altered mental status.

Influence of the cone angle and crystal shape on the formation of twins in InP crystals

International Nuclear Information System (INIS)

Li, Xiaolan; Yang, Ruixia; Yang, Fan; Sun, Tongnian; Sun, Niefeng

2012-01-01

We present the investigation of twinning phenomena of LEC InP crystal growth which has been carried out in our laboratory in recent years. It is observed that the yield of twin-free single crystal InP can be grown by control the cone angle and crystal shape of a gradually increased diameter. Twin formation has been correlated to many growth factors. The influence of ingot shape on the formation of twins can be looked as the conical angle dependent twin probability of InP crystals. Twin-free InP crystals can be grown by large cone angle over 75 to 90 . (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Adverse CNS-effects of beta-adrenoceptor blockers.

Science.gov (United States)

Gleiter, C H; Deckert, J

1996-11-01

In 1962 propranolol, the first beta adrenoceptor antagonist (beta blocker), was brought on to the market. There is now a host of different beta blockers available, and these compounds are among the most commonly prescribed groups of drugs. The efficacy of beta blockers has been proven predominantly for the treatment of cardiovascular diseases. Beta blockers are also used for certain types of CNS disorders, such as anxiety disorders, essential tremor and migraine. While low toxicity means that they have a favorable risk-benefit ratio, given the high intensity of use, it is essential to have a comprehensive knowledge of adverse events. Adverse events of beta blockers that can be related to the CNS are quite often neglected, even in textbooks of clinical pharmacology or review articles, and thus often misdiagnosed. The following article, therefore, after summarizing the use of beta blockers for CNS indications, critically reviews the literature on centrally mediated adverse events. General pharmacological features of beta blockers and their molecular basis of action will briefly be addressed to the extent that they are or may become relevant for central nervous pharmacotherapy and side-effects.

Differential expression of metallothioneins in the CNS of mice with experimental autoimmune encephalomyelitis

DEFF Research Database (Denmark)

Espejo, C; Carrasco, J; Hidalgo, J

2001-01-01

Multiple sclerosis is an inflammatory, demyelinating disease of the CNS. Metallothioneins-I+II are antioxidant proteins induced in the CNS by immobilisation stress, trauma or degenerative diseases which have been postulated to play a neuroprotective role, while the CNS isoform metallothionein......-III has been related to Alzheimer's disease. We have analysed metallothioneins-I-III expression in the CNS of mice with experimental autoimmune encephalomyelitis. Moreover, we have examined the putative role of interferon-gamma, a pro-inflammatory cytokine, in the control of metallothioneins expression...

Spectral characteristics of light sources for S-cone stimulation.

Science.gov (United States)

Schlegelmilch, F; Nolte, R; Schellhorn, K; Husar, P; Henning, G; Tornow, R P

2002-11-01

Electrophysiological investigations of the short-wavelength sensitive pathway of the human eye require the use of a suitable light source as a S-cone stimulator. Different light sources with their spectral distribution properties were investigated and compared with the ideal S-cone stimulator. First, the theoretical background of the calculation of relative cone energy absorption from the spectral distribution function of the light source is summarized. From the results of the calculation, the photometric properties of the ideal S-cone stimulator will be derived. The calculation procedure was applied to virtual light sources (computer generated spectral distribution functions with different medium wavelengths and spectrum widths) and to real light sources (blue and green light emitting diodes, blue phosphor of CRT-monitor, multimedia projector, LCD monitor and notebook display). The calculated relative cone absorbencies are compared to the conditions of an ideal S-cone stimulator. Monochromatic light sources with wavelengths of less than 456 nm are close to the conditions of an ideal S-cone stimulator. Spectrum widths up to 21 nm do not affect the S-cone activation significantly (S-cone activation change < 0.2%). Blue light emitting diodes with peak wavelength at 448 nm and spectrum bandwidth of 25 nm are very useful for S-cone stimulation (S-cone activation approximately 95%). A suitable display for S-cone stimulation is the Trinitron computer monitor (S-cone activation approximately 87%). The multimedia projector has a S-cone activation up to 91%, but their spectral distribution properties depends on the selected intensity. LCD monitor and notebook displays have a lower S-cone activation (< or = 74%). Carefully selecting the blue light source for S-cone stimulation can reduce the unwanted L-and M-cone activation down to 4% for M-cones and 1.5% for L-cones.

Light-cone observables and gauge-invariance in the geodesic light-cone formalism

Energy Technology Data Exchange (ETDEWEB)

Scaccabarozzi, Fulvio; Yoo, Jaiyul, E-mail: fulvio@physik.uzh.ch, E-mail: jyoo@physik.uzh.ch [Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zürich, Winterthurerstrasse 190, CH-8057, Zürich (Switzerland)

2017-06-01

The remarkable properties of the geodesic light-cone (GLC) coordinates allow analytic expressions for the light-cone observables, providing a new non-perturbative way for calculating the effects of inhomogeneities in our Universe. However, the gauge-invariance of these expressions in the GLC formalism has not been shown explicitly. Here we provide this missing part of the GLC formalism by proving the gauge-invariance of the GLC expressions for the light-cone observables, such as the observed redshift, the luminosity distance, and the physical area and volume of the observed sources. Our study provides a new insight on the properties of the GLC coordinates and it complements the previous work by the GLC collaboration, leading to a comprehensive description of light propagation in the GLC representation.

Gene therapy for CNS diseases – Krabbe disease

Directory of Open Access Journals (Sweden)

Mohammad A. Rafi

2016-06-01

Full Text Available This is a brief report of the 19th Annual Meeting of the American Society of Gene and Cell Therapy that took place from May 4th through May 7th, 2016 in Washington, DC, USA. While the meeting provided many symposiums, lectures, and scientific sessions this report mainly focuses on one of the sessions on the "Gene Therapy for central nervous system (CNS Diseases" and specifically on the "Gene Therapy for the globoid cell leukodystrophy or Krabbe disease. Two presentations focused on this subject utilizing two animal models of this disease: mice and dog models. Different serotypes of adeno-associate viral vectors (AAV alone or in combination with bone marrow transplantations were used in these research projects. The Meeting of the ASGCT reflected continuous growth in the fields of gene and cell therapy and brighter forecast for efficient treatment options for variety of human diseases.

CNS infiltration of peripheral immune cells: D-Day for neurodegenerative disease?

Science.gov (United States)

Rezai-Zadeh, Kavon; Gate, David; Town, Terrence

2009-12-01

While the central nervous system (CNS) was once thought to be excluded from surveillance by immune cells, a concept known as "immune privilege," it is now clear that immune responses do occur in the CNS-giving rise to the field of neuroimmunology. These CNS immune responses can be driven by endogenous (glial) and/or exogenous (peripheral leukocyte) sources and can serve either productive or pathological roles. Recent evidence from mouse models supports the notion that infiltration of peripheral monocytes/macrophages limits progression of Alzheimer's disease pathology and militates against West Nile virus encephalitis. In addition, infiltrating T lymphocytes may help spare neuronal loss in models of amyotrophic lateral sclerosis. On the other hand, CNS leukocyte penetration drives experimental autoimmune encephalomyelitis (a mouse model for the human demyelinating disease multiple sclerosis) and may also be pathological in both Parkinson's disease and human immunodeficiency virus encephalitis. A critical understanding of the cellular and molecular mechanisms responsible for trafficking of immune cells from the periphery into the diseased CNS will be key to target these cells for therapeutic intervention in neurodegenerative diseases, thereby allowing neuroregenerative processes to ensue.

Variability of silver fir (Abies alba Mill. cones – variability of cone parameters

Directory of Open Access Journals (Sweden)

Aniszewska Monika

2016-09-01

Full Text Available This study aimed at determining the shape of closed silver fir cones from the Jawor Forest District (Wroclaw, based purely on measurements of their length and thickness. Using these two parameters, the most accurate estimations were achieved with a fourth-degree polynomial fitting function. We then calculated the cones’ surface area and volume in three different ways: 1 Using the fourth-degree polynomial shape estimation, 2 Introducing indicators of compliance (k1, k2, k3 to calculate the volume and then comparing it to its actual value as measured in a pitcher filled with water, 3 Comparing the surface area of the cones as calculated with the polynomial function to the value obtained from ratios of indicators of compliance (ratios k4 and k5. We found that the calculated surface area and volume were substantially higher than the corresponding measured values. Test values of cone volume and surface area as calculated by our model were 8% and 5% lower, respectively, compared to direct measurements. We also determined the fir cones apparent density to be 0.8 g·cm-3on average. The gathered data on cone surface area, volume and bulk density is a valuable tool for optimizing the thermal peeling process in mill cabinets to acquire high quality seeds.

Méthode analytique généralisée pour le calcul du coning. Nouvelle solution pour calculer le coning de gaz, d'eau et double coning dans les puits verticaux et horizontaux Generalized Analytical Method for Coning Calculation. New Solution to Calculation Both the Gas Coning, Water Coning and Dual Coning for Vertical and Horizontal Wells

Directory of Open Access Journals (Sweden)

Pietraru V.

2006-11-01

Full Text Available Une nouvelle méthode analytique d'évaluation du coning d'eau par bottom water drive et/ou de gaz par gas-cap drive dans les puits horizontaux et verticaux a été développée pour les réservoirs infinis [1]. Dans cet article, une généralisation de cette méthode est présentée pour les réservoirs confinés d'extension limitée dont le toit est horizontal. La généralisation proposée est basée sur la résolution des équations différentielles de la diffusivité avec prise en compte des effets de drainage par gravité et des conditions aux limites pour un réservoir confiné. La méthode est applicable aux réservoirs isotropes ou anisotropes. L'hypothèse de pression constante à la limite de l'aire de drainage dans l'eau et/ou dans le gaz a été adoptée. Les pertes de charge dans l'aquifère et dans le gas-cap sont donc négligées. Les principales contributions de cet article sont : - L'introduction de la notion de rayon de cône, différent du rayon de puits. La hauteur du cône et le débit critique dépendent du rayon de cône alors qu'ils sont indépendants du rayon du puits. - Une nouvelle corrélation pour le calcul du débit critique sous forme adimensionnelle en fonction de trois paramètres : le temps, la longueur du drain horizontal (nulle pour un puits vertical et le rayon de drainage. - Des corrélations pour le calcul du rapport des débits gaz/huile (GOR ou de la fraction en eau (fw, pendant les périodes critique et postcritique, qui tiennent compte de la pression capillaire et des perméabilités relatives. - Des corrélations pour le calcul des rapports de débits gaz/huile et eau/huile pendant les périodes pré, post et supercritique en double coning. - Des critères pour le calcul du temps de percée au puits en simple coning de gaz ou d'eau, ou en double coning de gaz et d'eau. A new analytical method for assessing water and/or gas coning in horizontal and vertical wells has been developed for infinite

Drug Delivery to CNS: Challenges and Opportunities with Emphasis on Biomaterials Based Drug Delivery Strategies.

Science.gov (United States)

Khambhla, Ekta; Shah, Viral; Baviskar, Kalpesh

2016-01-01

The current epoch has witnessed a lifestyle impregnated with stress, which is a major cause of several neurological disorders. High morbidity and mortality rate due to neurological diseases and disorders have generated a huge social impact. Despite voluminous research, patients suffering from fatal and/or debilitating CNS diseases such as brain tumors, HIV, encephalopathy, Alzheimer's, epilepsy, Parkinson's, migraine and multiple sclerosis outnumbered those suffering from systemic cancer or heart diseases. The brain being a highly sensitive neuronal organ, has evolved with vasculature barriers, which regulates the efflux and influx of substances to CNS. Treatment of CNS diseases/disorders is challenging because of physiologic, metabolic and biochemical obstacles created by these barriers which comprise mainly of BBB and BCFB. The inability of achieving therapeutically active concentration has become the bottleneck level difficulty, hampering the therapeutic efficiency of several promising drug candidates for CNS related disorders. Parallel maturation of an effective CNS drug delivery strategy with CNS drug discovery is the need of the hour. Recently, the focus of the pharmaceutical community has aggravated in the direction of developing novel and more efficient drug delivery systems, giving the potential of more effective and safer CNS therapies. The present review outlines several hurdles in drug delivery to the CNS along with ideal physicochemical properties desired in drug substance/formulation for CNS delivery. The review also focuses on different conventional and novel strategies for drug delivery to the CNS. The article also assesses and emphasizes on possible benefits of biomaterial based formulations for drug delivery to the CNS.

Causes of CNS inflammation and potential targets for anticonvulsants.

Science.gov (United States)

Falip, Mercé; Salas-Puig, Xavier; Cara, Carlos

2013-08-01

Inflammation is one of the most important endogenous defence mechanisms in an organism. It has been suggested that inflammation plays an important role in the pathophysiology of a number of human epilepsies and convulsive disorders, and there is clinical and experimental evidence to suggest that inflammatory processes within the CNS may either contribute to or be a consequence of epileptogenesis. This review discusses evidence from human studies on the role of inflammation in epilepsy and highlights potential new targets in the inflammatory cascade for antiepileptic drugs. A number of mechanisms have been shown to be involved in CNS inflammatory reactions. These include an inflammatory response at the level of the blood-brain barrier (BBB), immune-mediated damage to the CNS, stress-induced release of inflammatory mediators and direct neuronal dysfunction or damage as a result of inflammatory reactions. Mediators of inflammation in the CNS include interleukin (IL)-1β, tumour necrosis factor-α, nuclear factor-κB and toll-like receptor-4 (TLR4). IL-1β, BBB and high-mobility group box-1-TLR4 signalling appear to be the most promising targets for anticonvulsant agents directed at inflammation. Such agents may provide effective therapy for drug-resistant epilepsies in the future.

Pericytes Stimulate Oligodendrocyte Progenitor Cell Differentiation during CNS Remyelination

Directory of Open Access Journals (Sweden)

Alerie Guzman De La Fuente

2017-08-01

Full Text Available The role of the neurovascular niche in CNS myelin regeneration is incompletely understood. Here, we show that, upon demyelination, CNS-resident pericytes (PCs proliferate, and parenchymal non-vessel-associated PC-like cells (PLCs rapidly develop. During remyelination, mature oligodendrocytes were found in close proximity to PCs. In Pdgfbret/ret mice, which have reduced PC numbers, oligodendrocyte progenitor cell (OPC differentiation was delayed, although remyelination proceeded to completion. PC-conditioned medium accelerated and enhanced OPC differentiation in vitro and increased the rate of remyelination in an ex vivo cerebellar slice model of demyelination. We identified Lama2 as a PC-derived factor that promotes OPC differentiation. Thus, the functional role of PCs is not restricted to vascular homeostasis but includes the modulation of adult CNS progenitor cells involved in regeneration.

Use of RI-cone penetrometer in clay foundations

International Nuclear Information System (INIS)

Mimura, Mamoru; Shibata, Toru; Shrivastava, A.K.

1993-01-01

RI cone penetrometer tests are carried out at four different sites. The foundation grounds discussed here mainly consist of clayey materials. The measured results by RI cone penetrometers are shown for Kyobashi, Hachirougata, Kurihama and Kinkai Bay site. According to comparison of water content and density profiles by RI cone measurement with the conventional testing results, RI cone penetrometers are proved to be versatile tools for site investigation. Settlement assessment by RI cone penetrometer is also discussed by exemplifying the embankment at Kinkai Bay site. Elasto-vis-coplastic finite element analysis correspondingly performed strongly supports the RI cone based assessment. Repeated use of RI cone penetrometer with the advance of construction enables us to assess the consolidation process of the clay foundation. (author)

Electromagnetic ion-cyclotron instability in the presence of a parallel electric field with general loss-cone distribution function - particle aspect analysis

Directory of Open Access Journals (Sweden)

G. Ahirwar

2006-08-01

Full Text Available The effect of parallel electric field on the growth rate, parallel and perpendicular resonant energy and marginal stability of the electromagnetic ion-cyclotron (EMIC wave with general loss-cone distribution function in a low β homogeneous plasma is investigated by particle aspect approach. The effect of the steepness of the loss-cone distribution is investigated on the electromagnetic ion-cyclotron wave. The whole plasma is considered to consist of resonant and non-resonant particles. It is assumed that resonant particles participate in the energy exchange with the wave, whereas non-resonant particles support the oscillatory motion of the wave. The wave is assumed to propagate parallel to the static magnetic field. The effect of the parallel electric field with the general distribution function is to control the growth rate of the EMIC waves, whereas the effect of steep loss-cone distribution is to enhance the growth rate and perpendicular heating of the ions. This study is relevant to the analysis of ion conics in the presence of an EMIC wave in the auroral acceleration region of the Earth's magnetoplasma.

Sonic Hedgehog switches on Wnt/planar cell polarity signaling in commissural axon growth cones by reducing levels of Shisa2

Science.gov (United States)

Onishi, Keisuke

2017-01-01

Commissural axons switch on responsiveness to Wnt attraction during midline crossing and turn anteriorly only after exiting the floor plate. We report here that Sonic Hedgehog (Shh)-Smoothened signaling downregulates Shisa2, which inhibits the glycosylation and cell surface presentation of Frizzled3 in rodent commissural axon growth cones. Constitutive Shisa2 expression causes randomized turning of post-crossing commissural axons along the anterior–posterior (A–P) axis. Loss of Shisa2 led to precocious anterior turning of commissural axons before or during midline crossing. Post-crossing commissural axon turning is completely randomized along the A–P axis when Wntless, which is essential for Wnt secretion, is conditionally knocked out in the floor plate. This regulatory link between Shh and planar cell polarity (PCP) signaling may also occur in other developmental processes. PMID:28885142

Implementation of Tuy's cone-beam inversion formula

International Nuclear Information System (INIS)

Zeng, G.L.; Clack, R.; Gullberg, G.T.

1994-01-01

Tuy's cone-beam inversion formula was modified to develop a cone-beam reconstruction algorithm. The algorithm was implemented for a cone-beam vertex orbit consisting of a circle and two orthogonal lines. This orbit geometry satisfies the cone-beam data sufficiency condition and is easy to implement on commercial single photon emission computed tomography (SPECT) systems. The algorithm which consists of two derivative steps, one rebinning step, and one three-dimensional backprojection step, was verified by computer simulations and by reconstructing physical phantom data collected on a clinical SPECT system. The proposed algorithm gives equivalent results and is as efficient as other analytical cone-beam reconstruction algorithms. (Author)

Cerebral blood flow variations in CNS lupus

International Nuclear Information System (INIS)

Kushner, M.J.; Tobin, M.; Fazekas, F.; Chawluk, J.; Jamieson, D.; Freundlich, B.; Grenell, S.; Freemen, L.; Reivich, M.

1990-01-01

We studied the patterns of cerebral blood flow (CBF), over time, in patients with systemic lupus erythematosus and varying neurologic manifestations including headache, stroke, psychosis, and encephalopathy. For 20 paired xenon-133 CBF measurements, CBF was normal during CNS remissions, regardless of the symptoms. CBF was significantly depressed during CNS exacerbations. The magnitude of change in CBF varied with the neurologic syndrome. CBF was least affected in patients with nonspecific symptoms such as headache or malaise, whereas patients with encephalopathy or psychosis exhibited the greatest reductions in CBF. In 1 patient with affective psychosis, without clinical or CT evidence of cerebral ischemia, serial SPECT studies showed resolution of multifocal cerebral perfusion defects which paralleled clinical recovery

Basic Concepts of CNS Development.

Science.gov (United States)

Nowakowski, R. S.

1987-01-01

The goals of this review are to: (1) provide a set of concepts to aid in the understanding of complex processes which occur during central nervous system (CNS) development; (2) illustrate how they contribute to our knowlege of adult brain anatomy; and (3) delineate how modifications of normal developmental processes may affect the structure and…

Handling data redundancy in helical cone beam reconstruction with a cone-angle-based window function and its asymptotic approximation

International Nuclear Information System (INIS)

Tang Xiangyang; Hsieh Jiang

2007-01-01

A cone-angle-based window function is defined in this manuscript for image reconstruction using helical cone beam filtered backprojection (CB-FBP) algorithms. Rather than defining the window boundaries in a two-dimensional detector acquiring projection data for computed tomographic imaging, the cone-angle-based window function deals with data redundancy by selecting rays with the smallest cone angle relative to the reconstruction plane. To be computationally efficient, an asymptotic approximation of the cone-angle-based window function is also given and analyzed in this paper. The benefit of using such an asymptotic approximation also includes the avoidance of functional discontinuities that cause artifacts in reconstructed tomographic images. The cone-angle-based window function and its asymptotic approximation provide a way, equivalent to the Tam-Danielsson-window, for helical CB-FBP reconstruction algorithms to deal with data redundancy, regardless of where the helical pitch is constant or dynamically variable during a scan. By taking the cone-parallel geometry as an example, a computer simulation study is conducted to evaluate the proposed window function and its asymptotic approximation for helical CB-FBP reconstruction algorithm to handle data redundancy. The computer simulated Forbild head and thorax phantoms are utilized in the performance evaluation, showing that the proposed cone-angle-based window function and its asymptotic approximation can deal with data redundancy very well in cone beam image reconstruction from projection data acquired along helical source trajectories. Moreover, a numerical study carried out in this paper reveals that the proposed cone-angle-based window function is actually equivalent to the Tam-Danielsson-window, and rigorous mathematical proofs are being investigated

Double Dirac cones in phononic crystals

KAUST Repository

Li, Yan

2014-07-07

A double Dirac cone is realized at the center of the Brillouin zone of a two-dimensional phononic crystal (PC) consisting of a triangular array of core-shell-structure cylinders in water. The double Dirac cone is induced by the accidental degeneracy of two double-degenerate Bloch states. Using a perturbation method, we demonstrate that the double Dirac cone is composed of two identical and overlapping Dirac cones whose linear slopes can also be accurately predicted from the method. Because the double Dirac cone occurs at a relatively low frequency, a slab of the PC can be mapped onto a slab of zero refractive index material by using a standard retrieval method. Total transmission without phase change and energy tunneling at the double Dirac point frequency are unambiguously demonstrated by two examples. Potential applications can be expected in diverse fields such as acoustic wave manipulations and energy flow control.

Double Dirac cones in phononic crystals

KAUST Repository

Li, Yan; Wu, Ying; Mei, Jun

2014-01-01

A double Dirac cone is realized at the center of the Brillouin zone of a two-dimensional phononic crystal (PC) consisting of a triangular array of core-shell-structure cylinders in water. The double Dirac cone is induced by the accidental degeneracy of two double-degenerate Bloch states. Using a perturbation method, we demonstrate that the double Dirac cone is composed of two identical and overlapping Dirac cones whose linear slopes can also be accurately predicted from the method. Because the double Dirac cone occurs at a relatively low frequency, a slab of the PC can be mapped onto a slab of zero refractive index material by using a standard retrieval method. Total transmission without phase change and energy tunneling at the double Dirac point frequency are unambiguously demonstrated by two examples. Potential applications can be expected in diverse fields such as acoustic wave manipulations and energy flow control.

The retina as a window to the brain-from eye research to CNS disorders.

Science.gov (United States)

London, Anat; Benhar, Inbal; Schwartz, Michal

2013-01-01

Philosophers defined the eye as a window to the soul long before scientists addressed this cliché to determine its scientific basis and clinical relevance. Anatomically and developmentally, the retina is known as an extension of the CNS; it consists of retinal ganglion cells, the axons of which form the optic nerve, whose fibres are, in effect, CNS axons. The eye has unique physical structures and a local array of surface molecules and cytokines, and is host to specialized immune responses similar to those in the brain and spinal cord. Several well-defined neurodegenerative conditions that affect the brain and spinal cord have manifestations in the eye, and ocular symptoms often precede conventional diagnosis of such CNS disorders. Furthermore, various eye-specific pathologies share characteristics of other CNS pathologies. In this Review, we summarize data that support examination of the eye as a noninvasive approach to the diagnosis of select CNS diseases, and the use of the eye as a valuable model to study the CNS. Translation of eye research to CNS disease, and deciphering the role of immune cells in these two systems, could improve our understanding and, potentially, the treatment of neurodegenerative disorders.

Effects of prolonged treatment with memantine in the MRL model of CNS lupus.

Science.gov (United States)

Marcinko, Katarina; Parsons, Tiffany; Lerch, Jason P; Sled, John G; Sakic, Boris

2012-09-01

Neuropsychiatric manifestations and brain atrophy of unknown etiology are common and severe complications of systemic lupus erythematosus (SLE). An autoantibody that binds to N-methyl-D-aspartate (NMDA) receptor NR2 has been proposed as a key factor in the etiology of central nervous system (CNS) SLE. This hypothesis was supported by evidence suggesting memantine (MEM), an uncompetitive NMDA receptor antagonist, prevents behavioral dysfunction and brain pathology in healthy mice immunized with a peptide similar to an epitope on the NR2 receptor. Given that SLE is a chronic condition, we presently examine the effects of MEM in MRL/lpr mice, which develop behavioral deficits alongside SLE-like disease. A broad behavioral battery and 7-Tesla MRI were used to examine whether prolonged treatment with MEM (~25 mg/kg b.w. in drinking water) prevents CNS involvement in this spontaneous model of SLE. Although MEM increased novel object exploration in MRL/lpr mice, it did not show other beneficial, substrain-specific effects. Conversely, MEM was detrimental to spontaneous activity in control MRL +/+ mice and had a negative effect on body mass gain. Similarly, MRI revealed comparable increases in the volume of periventricular structures in MEM-treated groups. Sustained exposure to MEM affects body growth, brain morphology, and behavior primarily by pharmacological, and not autoimmunity-dependant mechanisms. Substrain-specific improvement in exploratory behavior of MEM-treated MRL/lpr mice may indicate that the NMDA system is merely a constituent of a complex pathogenenic cascade. However, it was evident that chronic administration of MEM is unable to completely prevent the development of a CNS SLE-like syndrome.

Cone-based Electrical Resistivity Tomography

Science.gov (United States)

Pidlisecky, A.; Knight, R.; Haber, E.

2005-05-01

Determining the 3D spatial distribution of subsurface properties is a critical part of managing the clean-up of contaminated sites. Most standard hydrologic methods sample small regions immediately adjacent to wells or testing devices. This provides data which are not representative of the entire region of interest. Furthermore, at many contaminated sites invasive methods are not acceptable, due to the risks associated with contacting and spreading the contaminants. To address these issues, we have developed a minimally invasive technology that provides information about the 3D distribution of electrical conductivity. This new technique, cone-based electrical resistivity tomography (C-bert), involves placing several permanent current electrodes in the subsurface and using electrodes mounted on a cone penetrometer to measure the resultant potential field while advancing the cone into the subsurface. In addition to potential field measurements, we obtain the standard suite of cone-penetration measurements, including high resolution resistivity logs; these data can then be used to constrain the inversion of the potential field data. A major challenge of working with these data is that the cone penetrometer is highly conductive, and thus presents a large local perturbation around the measurement location. As the cone is very small (approximately 30mm in diameter) with respect to the total model space, explicitly modeling the cone is computationally demanding. We developed a method for solving the forward model that reduces computational time by an order of magnitude. This solution method, iteratively determined boundary conditions, makes it possible to correct for the cone effect before inversion of the data. Results from synthetic experiments suggest that the C-bert method of data acquisition can result in high quality electrical conductivity images of the subsurface. We tested the practicality of this technique by performing a field test of the C-bert system to image

Dirac cones in isogonal hexagonal metallic structures

Science.gov (United States)

Wang, Kang

2018-03-01

A honeycomb hexagonal metallic lattice is equivalent to a triangular atomic one and cannot create Dirac cones in its electromagnetic wave spectrum. We study in this work the low-frequency electromagnetic band structures in isogonal hexagonal metallic lattices that are directly related to the honeycomb one and show that such structures can create Dirac cones. The band formation can be described by a tight-binding model that allows investigating, in terms of correlations between local resonance modes, the condition for the Dirac cones and the consequence of the third structure tile sustaining an extra resonance mode in the unit cell that induces band shifts and thus nonlinear deformation of the Dirac cones following the wave vectors departing from the Dirac points. We show further that, under structure deformation, the deformations of the Dirac cones result from two different correlation mechanisms, both reinforced by the lattice's metallic nature, which directly affects the resonance mode correlations. The isogonal structures provide new degrees of freedom for tuning the Dirac cones, allowing adjustment of the cone shape by modulating the structure tiles at the local scale without modifying the lattice periodicity and symmetry.

An Automated Strategy for Unbiased Morphometric Analyses and Classifications of Growth Cones In Vitro.

Science.gov (United States)

Chitsaz, Daryan; Morales, Daniel; Law, Chris; Kania, Artur

2015-01-01

During neural circuit development, attractive or repulsive guidance cue molecules direct growth cones (GCs) to their targets by eliciting cytoskeletal remodeling, which is reflected in their morphology. The experimental power of in vitro neuronal cultures to assay this process and its molecular mechanisms is well established, however, a method to rapidly find and quantify multiple morphological aspects of GCs is lacking. To this end, we have developed a free, easy to use, and fully automated Fiji macro, Conographer, which accurately identifies and measures many morphological parameters of GCs in 2D explant culture images. These measurements are then subjected to principle component analysis and k-means clustering to mathematically classify the GCs as "collapsed" or "extended". The morphological parameters measured for each GC are found to be significantly different between collapsed and extended GCs, and are sufficient to classify GCs as such with the same level of accuracy as human observers. Application of a known collapse-inducing ligand results in significant changes in all parameters, resulting in an increase in 'collapsed' GCs determined by k-means clustering, as expected. Our strategy provides a powerful tool for exploring the relationship between GC morphology and guidance cue signaling, which in particular will greatly facilitate high-throughput studies of the effects of drugs, gene silencing or overexpression, or any other experimental manipulation in the context of an in vitro axon guidance assay.

Problems of prophylactic CNS radiotherapy in acute children's leukemia

International Nuclear Information System (INIS)

Bek, V.; Pribylova, O.; Abrahamova, J.; Hynieova, H.; Hrodek, O.

1980-01-01

The prophylactic treatment of the CNS was conducted by cobalt teletherapy of the cranium and by intrathecal application of MTX after the induction of primary remission in 70 children with acute leukemia throughout 5 years up to the end of 1978. The method of the combined radio- and chemoprophylaxis of the CNS was being changed during the years, especially as far as the radiation dose for the cranium was concerned. A detailed analysis made in a group of 59 children with the minimum interval of 18 months from the beginning of the treatment showed the best results after the application of a dose of 24 Gy/3 weeks. Following this procedure the relapse of leukemia in the CNS occurred in 9% only, whereas on the application of doses of 20 Gy and lower it occurred in 35 to 40%. On the whole 24 out of 59 children, i.e. 41%, are surviving, 35 children, i.e. 59%, died. Mostly complete, but only temporary, epilation was an invariable consequence of the irradiation of the cranium. The somnolence syndrome was only sporadically observed. It cannot be excluded, however, that some of its forms in patients discharged from hospital escaped attention. No case was recorded of serious impairment of the CNS of the leukoencephalopathic type. Up to now the psychomotor, intellectual and emotional development of the surviving children has been normal. (author)

g-Weak Contraction in Ordered Cone Rectangular Metric Spaces

Directory of Open Access Journals (Sweden)

S. K. Malhotra

2013-01-01

Full Text Available We prove some common fixed-point theorems for the ordered g-weak contractions in cone rectangular metric spaces without assuming the normality of cone. Our results generalize some recent results from cone metric and cone rectangular metric spaces into ordered cone rectangular metric spaces. Examples are provided which illustrate the results.

VIIP: Central Nervous System (CNS) Modeling

Science.gov (United States)

Vera, Jerry; Mulugeta, Lealem; Nelson, Emily; Raykin, Julia; Feola, Andrew; Gleason, Rudy; Samuels, Brian; Ethier, C. Ross; Myers, Jerry

2015-01-01

Current long-duration missions to the International Space Station and future exploration-class missions beyond low-Earth orbit expose astronauts to increased risk of Visual Impairment and Intracranial Pressure (VIIP) syndrome. It has been hypothesized that the headward shift of cerebrospinal fluid (CSF) and blood in microgravity may cause significant elevation of intracranial pressure (ICP), which in turn may then induce VIIP syndrome through interaction with various biomechanical pathways. However, there is insufficient evidence to confirm this hypothesis. In this light, we are developing lumped-parameter models of fluid transport in the central nervous system (CNS) as a means to simulate the influence of microgravity on ICP. The CNS models will also be used in concert with the lumped parameter and finite element models of the eye described in the related IWS works submitted by Nelson et al., Feola et al. and Ethier et al.

CNS metastasis from malignant uveal melanoma: a clinical and histopathological characterisation

DEFF Research Database (Denmark)

Holfort, S K; Lindegaard, J; Isager, P

2008-01-01

was observed in two cases (14%). The amount of tumour infiltrating lymphocytes was pronounced in three cases (23%). CONCLUSION: The proportion of uveal melanoma patients having CNS metastasis was 0.7%. Eleven patients had multiple organ metastases, and the average time from the initial CNS symptoms to death...

Constructing anisotropic single-Dirac-cones in Bi(1-x)Sb(x) thin films.

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Tang, Shuang; Dresselhaus, Mildred S

2012-04-11

The electronic band structures of Bi(1-x)Sb(x) thin films can be varied as a function of temperature, pressure, stoichiometry, film thickness, and growth orientation. We here show how different anisotropic single-Dirac-cones can be constructed in a Bi(1-x)Sb(x) thin film for different applications or research purposes. For predicting anisotropic single-Dirac-cones, we have developed an iterative-two-dimensional-two-band model to get a consistent inverse-effective-mass-tensor and band gap, which can be used in a general two-dimensional system that has a nonparabolic dispersion relation as in the Bi(1-x)Sb(x) thin film system. © 2012 American Chemical Society

Interneuron progenitor transplantation to treat CNS dysfunction

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Muhammad O Chohan

2016-08-01

Full Text Available Due to the inadequacy of endogenous repair mechanisms diseases of the nervous system remain a major challenge to scientists and clinicians. Stem cell based therapy is an exciting and viable strategy that has been shown to ameliorate or even reverse symptoms of CNS dysfunction in preclinical animal models. Of particular importance has been the use of GABAergic interneuron progenitors as a therapeutic strategy. Born in the neurogenic niches of the ventral telencephalon, interneuron progenitors retain their unique capacity to disperse, integrate and induce plasticity in adult host circuitries following transplantation. Here we discuss the potential of interneuron based transplantation strategies as it relates to CNS disease therapeutics. We also discuss mechanisms underlying their therapeutic efficacy and some of the challenges that face the field.

Neuroprotective effects of estrogen in CNS injuries: insights from animal models

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Raghava N

2017-07-01

Full Text Available Narayan Raghava,1 Bhaskar C Das,2 Swapan K Ray1 1Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, USA; 2Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA Abstract: Among the estrogens that are biosynthesized in the human body, 17β-estradiol (estradiol or E2 is the most common and the best estrogen for neuroprotection in animal models of the central nervous system (CNS injuries such as spinal cord injury (SCI, traumatic brain injury (TBI, and ischemic brain injury (IBI. These CNS injuries are not only serious health problems, but also enormous economic burden on the patients, their families, and the society at large. Studies from animal models of these CNS injuries provide insights into the multiple neuroprotective mechanisms of E2 and also suggest the possibility of translating the therapeutic efficacy of E2 in the treatment SCI, TBI, and IBI in humans in the near future. The pathophysiology of these injuries includes loss of motor function in the limbs, arms and their extremities, cognitive deficit, and many other serious consequences including life-threatening paralysis, infection, and even death. The potential application of E2 therapy to treat the CNS injuries may become a trend as the results are showing significant therapeutic benefits of E2 for neuroprotection when administered into the animal models of SCI, TBI, and IBI. This article describes the plausible mechanisms how E2 works with or without the involvement of estrogen receptors and provides an overview of the known neuroprotective effects of E2 in these three CNS injuries in different animal models. Because activation of estrogen receptors has profound implications in maintaining and also affecting normal physiology, there are notable impediments in translating E2 therapy to the clinics for neuroprotection in CNS injuries in humans. While E2 may not yet be the sole molecule for

Singularities of plane complex curves and limits of Kähler metrics with cone singularities. I: Tangent Cones

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Borbon Martin de

2017-02-01

Full Text Available The goal of this article is to provide a construction and classification, in the case of two complex dimensions, of the possible tangent cones at points of limit spaces of non-collapsed sequences of Kähler-Einstein metrics with cone singularities. The proofs and constructions are completely elementary, nevertheless they have an intrinsic beauty. In a few words; tangent cones correspond to spherical metrics with cone singularities in the projective line by means of the Kähler quotient construction with respect to the S1-action generated by the Reeb vector field, except in the irregular case ℂβ₁×ℂβ₂ with β₂/ β₁ ∉ Q.

Foxp3+ regulatory T cells control persistence of viral CNS infection.

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Dajana Reuter

Full Text Available We earlier established a model of a persistent viral CNS infection using two week old immunologically normal (genetically unmodified mice and recombinant measles virus (MV. Using this model infection we investigated the role of regulatory T cells (Tregs as regulators of the immune response in the brain, and assessed whether the persistent CNS infection can be modulated by manipulation of Tregs in the periphery. CD4(+ CD25(+ Foxp3(+ Tregs were expanded or depleted during the persistent phase of the CNS infection, and the consequences for the virus-specific immune response and the extent of persistent infection were analyzed. Virus-specific CD8(+ T cells predominantly recognising the H-2D(b-presented viral hemagglutinin epitope MV-H(22-30 (RIVINREHL were quantified in the brain by pentamer staining. Expansion of Tregs after intraperitoneal (i.p. application of the superagonistic anti-CD28 antibody D665 inducing transient immunosuppression caused increased virus replication and spread in the CNS. In contrast, depletion of Tregs using diphtheria toxin (DT in DEREG (depletion of regulatory T cells-mice induced an increase of virus-specific CD8(+ effector T cells in the brain and caused a reduction of the persistent infection. These data indicate that manipulation of Tregs in the periphery can be utilized to regulate virus persistence in the CNS.

Light cone thermodynamics

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De Lorenzo, Tommaso; Perez, Alejandro

2018-02-01

We show that null surfaces defined by the outgoing and infalling wave fronts emanating from and arriving at a sphere in Minkowski spacetime have thermodynamical properties that are in strict formal correspondence with those of black hole horizons in curved spacetimes. Such null surfaces, made of pieces of light cones, are bifurcate conformal Killing horizons for suitable conformally stationary observers. They can be extremal and nonextremal depending on the radius of the shining sphere. Such conformal Killing horizons have a constant light cone (conformal) temperature, given by the standard expression in terms of the generalization of surface gravity for conformal Killing horizons. Exchanges of conformally invariant energy across the horizon are described by a first law where entropy changes are given by 1 /(4 ℓp2) of the changes of a geometric quantity with the meaning of horizon area in a suitable conformal frame. These conformal horizons satisfy the zeroth to the third laws of thermodynamics in an appropriate way. In the extremal case they become light cones associated with a single event; these have vanishing temperature as well as vanishing entropy.

Management of CNS tumors

International Nuclear Information System (INIS)

Griem, M.L.

1987-01-01

The treatment of tumors of the CNS has undergone a number of changes based on the impact of CT. The use of intraoperative US for the establishment of tumor location and tumor histology is demonstrated. MR imaging also is beginning to make an impact on the diagnosis and treatment of tumors of the CNS. Examples of MR images are shown. The authors then discuss the important aspects of tumor histology as it affects management and newer concepts in surgery, radiation, and chemotherapy on tumor treatment. The role of intraoperative placement of radioactive sources, the utilization of heavy particle radiation therapy, and the potential role of other experimental radiation therapy techniques are discussed. The role of hyperfractionated radiation and of neutrons and x-ray in a mixed-beam treatment are discussed in perspective with standard radiation therapy. Current chemotherapy techniques, including intraarterial chemotherapy, are discussed. The complications of radiation therapy alone and in combination with chemotherapy in the management of primary brain tumors, brain metastases, and leukemia are reviewed. A summary of the current management of pituitary tumors, including secreting pituitary adenomas and chromophobe adenomas, are discussed. The treatment with heavy particle radiation, transsphenoidal microsurgical removal, and combined radiotherapeutic and surgical management are considered. Tumor metastasis management of lesions of the brain and spinal cord are considered

Cone dystrophy with "supernormal" rod ERG: psychophysical testing shows comparable rod and cone temporal sensitivity losses with no gain in rod function.

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Stockman, Andrew; Henning, G Bruce; Michaelides, Michel; Moore, Anthony T; Webster, Andrew R; Cammack, Jocelyn; Ripamonti, Caterina

2014-02-10

We report a psychophysical investigation of 5 observers with the retinal disorder "cone dystrophy with supernormal rod ERG," caused by mutations in the gene KCNV2 that encodes a voltage-gated potassium channel found in rod and cone photoreceptors. We compared losses for rod- and for cone-mediated vision to further investigate the disorder and to assess whether the supernormal ERG is associated with any visual benefit. L-cone, S-cone, and rod temporal acuity (critical flicker fusion frequency) were measured as a function of target irradiance; L-cone temporal contrast sensitivity was measured as a function of temporal frequency. Temporal acuity measures revealed that losses for vision mediated by rods, S-cones, and L-cones are roughly equivalent. Further, the gain in rod function implied by the supernormal ERG provides no apparent benefit to near-threshold rod-mediated visual performance. The L-cone temporal contrast sensitivity function in affected observers was similar in shape to the mean normal function but only after the mean function was compressed by halving the logarithmic sensitivities. The name of this disorder is potentially misleading because the comparable losses found across rod and cone vision suggest that the disorder is a generalized cone-rod dystrophy. Temporal acuity and temporal contrast sensitivity measures are broadly consistent with the defect in the voltage-gated potassium channel producing a nonlinear distortion of the photoreceptor response but after otherwise normal transduction processes.

Stereotyped Synaptic Connectivity Is Restored during Circuit Repair in the Adult Mammalian Retina.

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Beier, Corinne; Palanker, Daniel; Sher, Alexander

2018-06-04

Proper function of the central nervous system (CNS) depends on the specificity of synaptic connections between cells of various types. Cellular and molecular mechanisms responsible for the establishment and refinement of these connections during development are the subject of an active area of research [1-6]. However, it is unknown if the adult mammalian CNS can form new type-selective synapses following neural injury or disease. Here, we assess whether selective synaptic connections can be reestablished after circuit disruption in the adult mammalian retina. The stereotyped circuitry at the first synapse in the retina, as well as the relatively short distances new neurites must travel compared to other areas of the CNS, make the retina well suited to probing for synaptic specificity during circuit reassembly. Selective connections between short-wavelength sensitive cone photoreceptors (S-cones) and S-cone bipolar cells provides the foundation of the primordial blue-yellow vision, common to all mammals [7-18]. We take advantage of the ground squirrel retina, which has a one-to-one S-cone-to-S-cone-bipolar-cell connection, to test if this connectivity can be reestablished following local photoreceptor loss [8, 19]. We find that after in vivo selective photoreceptor ablation, deafferented S-cone bipolar cells expand their dendritic trees. The new dendrites randomly explore the proper synaptic layer, bypass medium-wavelength sensitive cone photoreceptors (M-cones), and selectively synapse with S-cones. However, non-connected dendrites are not pruned back to resemble unperturbed S-cone bipolar cells. We show, for the first time, that circuit repair in the adult mammalian retina can recreate stereotypic selective wiring. Copyright © 2018 Elsevier Ltd. All rights reserved.

Novel agents in CNS myeloma treatment.

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Gozzetti, Alessandro; Cerase, Alfonso

2014-01-01

Central nervous system localization of multiple myeloma (CNS-MM) accounts for about 1% of all MM.Treatment is still unsatisfactory. Many treatments have been described in the literature: chemotherapy (CHT), intrathecal therapy (IT), and radiotherapy (RT), with survivals reported between one month and six months. Recent drugs such as the immunomodulatory drugs (IMiDs) and proteasome inhibitors (bortezomib) have changed the treatment of patients with MM, both younger and older, with a significant improvement in response and survival. The activity of new drugs in CNSMM has been reported but is still not well known. Bortezomib does not cross the blood brain barrier (BBB), and IMID’s seem to have only a minimal crossover. The role of novel agents in CNS MM management will be discussed as well as the potential role of other new immunomodulatory drugs (pomalidomide) and proteasome inhibitors that seem to cross the BBB and hold promise into the treatment of this rare and still incurable localization of the disease.

Multiple dendrochronological responses to the eruption of Cinder Cone, Lassen Volcanic National Park, California

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Sheppard, P.R.; Ort, M.H.; Anderson, K.C.; Clynne, M.A.; May, E.M.

2009-01-01

Two dendrochronological properties – ring width and ring chemistry – were investigated in trees near Cinder Cone in Lassen Volcanic National Park, northeastern California, for the purpose of re-evaluating the date of its eruption. Cinder Cone is thought to have erupted in AD 1666 based on ring-width evidence, but interpreting ring-width changes alone is not straightforward because many forest disturbances can cause changes in ring width. Old Jeffrey pines growing in Cinder Cone tephra and elsewhere for control comparison were sampled. Trees growing in tephra show synchronous ring-width changes at AD 1666, but this ring-width signal could be considered ambiguous for dating the eruption because changes in ring width can be caused by other events. Trees growing in tephra also show changes in ring phosphorus, sulfur, and sodium during the late 1660s, but inter-tree variability in dendrochemical signals makes dating the eruption from ring chemistry alone difficult. The combination of dendrochemistry and ring-width signals improves confidence in dating the eruption of Cinder Cone over the analysis of just one ring-growth property. These results are similar to another case study using dendrochronology of ring width and ring chemistry at Parícutin, Michoacán, Mexico, a cinder cone that erupted beginning in 1943. In both cases, combining analysis with ring width and ring chemistry improved confidence in the dendro-dating of the eruptions.

Persistent growth of a young andesite lava cone: Bagana volcano, Papua New Guinea

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Wadge, G.; McCormick Kilbride, B. T.; Edmonds, M.; Johnson, R. W.

2018-05-01

Bagana, an andesite lava cone on Bougainville Island, Papua New Guinea, is thought to be a very young central volcano. We have tested this idea by estimating the volumes of lava extruded over different time intervals (1-, 2-, 3-, 9-, 15-, 70-years) using digital elevation models (DEMs), mainly created from satellite data. Our results show that the long-term extrusion rate at Bagana, measured over years to decades, has remained at about 1.0 m3 s-1. We present models of the total edifice volume, and show that, if our measured extrusion rates are representative, the volcano could have been built in only 300 years. It could also possibly have been built at a slower rate during a longer, earlier period of growth. Six kilometres NNW of Bagana, an andesite-dacite volcano, Billy Mitchell, had a large, caldera-forming plinian eruption 437 years ago. We consider the possibility that, as a result of this eruption, the magma supply was diverted from Billy Mitchell to Bagana. It seems that Bagana is a rare example of a very youthful, polygenetic, andesite volcano. The characteristics of such a volcano, based on the example of Bagana, are: a preponderance of lava products over pyroclastic products, a high rate of lava extrusion maintained for decades, a very high rate of SO2 emission, evidence of magma batch fractionation and location in a trans-tensional setting at the end of an arc segment above a very steeply dipping and rapidly converging subduction zone.

CRALBP supports the mammalian retinal visual cycle and cone vision.

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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.

A cone-beam reconstruction algorithm using shift-variant filtering and cone-beam backprojection

International Nuclear Information System (INIS)

Defrise, M.; Clack, R.

1994-01-01

An exact inversion formula written in the form of shift-variant filtered-backprojection (FBP) is given for reconstruction from cone-beam data taken from any orbit satisfying Tuy's sufficiency conditions. The method is based on a result of Grangeat, involving the derivative of the three-dimensional (3-D) Radon transform, but unlike Grangeat's algorithm, no 3D rebinning step is required. Data redundancy, which occurs when several cone-beam projections supply the same values in the Radon domain, is handled using an elegant weighting function and without discarding data. The algorithm is expressed in a convenient cone-beam detector reference frame, and a specific example for the case of a dual orthogonal circular orbit is presented. When the method is applied to a single circular orbit, it is shown to be equivalent to the well-known algorithm of Feldkamp et al

Cone rod dystrophies

Science.gov (United States)

Hamel, Christian P

2007-01-01

Cone rod dystrophies (CRDs) (prevalence 1/40,000) are inherited retinal dystrophies that belong to the group of pigmentary retinopathies. CRDs are characterized by retinal pigment deposits visible on fundus examination, predominantly localized to the macular region. In contrast to typical retinitis pigmentosa (RP), also called the rod cone dystrophies (RCDs) resulting from the primary loss in rod photoreceptors and later followed by the secondary loss in cone photoreceptors, CRDs reflect the opposite sequence of events. CRD is characterized by primary cone involvement, or, sometimes, by concomitant loss of both cones and rods that explains the predominant symptoms of CRDs: decreased visual acuity, color vision defects, photoaversion and decreased sensitivity in the central visual field, later followed by progressive loss in peripheral vision and night blindness. The clinical course of CRDs is generally more severe and rapid than that of RCDs, leading to earlier legal blindness and disability. At end stage, however, CRDs do not differ from RCDs. CRDs are most frequently non syndromic, but they may also be part of several syndromes, such as Bardet Biedl syndrome and Spinocerebellar Ataxia Type 7 (SCA7). Non syndromic CRDs are genetically heterogeneous (ten cloned genes and three loci have been identified so far). The four major causative genes involved in the pathogenesis of CRDs are ABCA4 (which causes Stargardt disease and also 30 to 60% of autosomal recessive CRDs), CRX and GUCY2D (which are responsible for many reported cases of autosomal dominant CRDs), and RPGR (which causes about 2/3 of X-linked RP and also an undetermined percentage of X-linked CRDs). It is likely that highly deleterious mutations in genes that otherwise cause RP or macular dystrophy may also lead to CRDs. The diagnosis of CRDs is based on clinical history, fundus examination and electroretinogram. Molecular diagnosis can be made for some genes, genetic counseling is always advised. Currently

Cone rod dystrophies

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Hamel Christian P

2007-02-01

Full Text Available Abstract Cone rod dystrophies (CRDs (prevalence 1/40,000 are inherited retinal dystrophies that belong to the group of pigmentary retinopathies. CRDs are characterized by retinal pigment deposits visible on fundus examination, predominantly localized to the macular region. In contrast to typical retinitis pigmentosa (RP, also called the rod cone dystrophies (RCDs resulting from the primary loss in rod photoreceptors and later followed by the secondary loss in cone photoreceptors, CRDs reflect the opposite sequence of events. CRD is characterized by primary cone involvement, or, sometimes, by concomitant loss of both cones and rods that explains the predominant symptoms of CRDs: decreased visual acuity, color vision defects, photoaversion and decreased sensitivity in the central visual field, later followed by progressive loss in peripheral vision and night blindness. The clinical course of CRDs is generally more severe and rapid than that of RCDs, leading to earlier legal blindness and disability. At end stage, however, CRDs do not differ from RCDs. CRDs are most frequently non syndromic, but they may also be part of several syndromes, such as Bardet Biedl syndrome and Spinocerebellar Ataxia Type 7 (SCA7. Non syndromic CRDs are genetically heterogeneous (ten cloned genes and three loci have been identified so far. The four major causative genes involved in the pathogenesis of CRDs are ABCA4 (which causes Stargardt disease and also 30 to 60% of autosomal recessive CRDs, CRX and GUCY2D (which are responsible for many reported cases of autosomal dominant CRDs, and RPGR (which causes about 2/3 of X-linked RP and also an undetermined percentage of X-linked CRDs. It is likely that highly deleterious mutations in genes that otherwise cause RP or macular dystrophy may also lead to CRDs. The diagnosis of CRDs is based on clinical history, fundus examination and electroretinogram. Molecular diagnosis can be made for some genes, genetic counseling is

A growing field: The regulation of axonal regeneration by Wnt signaling.

Science.gov (United States)

Garcia, Armando L; Udeh, Adanna; Kalahasty, Karthik; Hackam, Abigail S

2018-01-01

The canonical Wnt/β-catenin pathway is a highly conserved signaling cascade that plays critical roles during embryogenesis. Wnt ligands regulate axonal extension, growth cone guidance and synaptogenesis throughout the developing central nervous system (CNS). Recently, studies in mammalian and fish model systems have demonstrated that Wnt/β-catenin signaling also promotes axonal regeneration in the adult optic nerve and spinal cord after injury, raising the possibility that Wnt could be developed as a therapeutic strategy. In this review, we summarize experimental evidence that reveals novel roles for Wnt signaling in the injured CNS, and discuss possible mechanisms by which Wnt ligands could overcome molecular barriers inhibiting axonal growth to promote regeneration. A central challenge in the neuroscience field is developing therapeutic strategies that induce robust axonal regeneration. Although adult axons have the capacity to respond to axonal guidance molecules after injury, there are several major obstacles for axonal growth, including extensive neuronal death, glial scars at the injury site, and lack of axonal guidance signals. Research in rodents demonstrated that activation of Wnt/β-catenin signaling in retinal neurons and radial glia induced neuronal survival and axonal growth, but that activation within reactive glia at the injury site promoted proliferation and glial scar formation. Studies in zebrafish spinal cord injury models confirm an axonal regenerative role for Wnt/β-catenin signaling and identified the cell types responsible. Additionally, in vitro and in vivo studies demonstrated that Wnt induces axonal and neurite growth through transcription-dependent effects of its central mediator β-catenin, potentially by inducing regeneration-promoting genes. Canonical Wnt signaling may also function through transcription-independent interactions of β-catenin with cytoskeletal elements, which could stabilize growing axons and control growth cone

Microtubule-Targeting Agents Enter the Central Nervous System (CNS): Double-edged Swords for Treating CNS Injury and Disease.

Science.gov (United States)

Hur, Eun-Mi; Lee, Byoung Dae

2014-12-01

Microtubules have been among the most successful targets in anticancer therapy and a large number of microtubule-targeting agents (MTAs) are in various stages of clinical development for the treatment of several malignancies. Given that injury and diseases in the central nervous system (CNS) are accompanied by acute or chronic disruption of the structural integrity of neurons and that microtubules provide structural support for the nervous system at cellular and intracellular levels, microtubules are emerging as potential therapeutic targets for treating CNS disorders. It has been postulated that exogenous application of MTAs might prevent the breakdown or degradation of microtubules after injury or during neurodegeneration, which will thereby aid in preserving the structural integrity and function of the nervous system. Here we review recent evidence that supports this notion and also discuss potential risks of targeting microtubules as a therapy for treating nerve injury and neurodegenerative diseases.

Microtubule-Targeting Agents Enter the Central Nervous System (CNS: Double-edged Swords for Treating CNS Injury and Disease

Directory of Open Access Journals (Sweden)

Eun-Mi Hur

2014-12-01

Full Text Available Microtubules have been among the most successful targets in anticancer therapy and a large number of microtubule-targeting agents (MTAs are in various stages of clinical development for the treatment of several malignancies. Given that injury and diseases in the central nervous system (CNS are accompanied by acute or chronic disruption of the structural integrity of neurons and that microtubules provide structural support for the nervous system at cellular and intracellular levels, microtubules are emerging as potential therapeutic targets for treating CNS disorders. It has been postulated that exogenous application of MTAs might prevent the breakdown or degradation of microtubules after injury or during neurodegeneration, which will thereby aid in preserving the structural integrity and function of the nervous system. Here we review recent evidence that supports this notion and also discuss potential risks of targeting microtubules as a therapy for treating nerve injury and neurodegenerative diseases.

An Automated Strategy for Unbiased Morphometric Analyses and Classifications of Growth Cones In Vitro.

Directory of Open Access Journals (Sweden)

Daryan Chitsaz

Full Text Available During neural circuit development, attractive or repulsive guidance cue molecules direct growth cones (GCs to their targets by eliciting cytoskeletal remodeling, which is reflected in their morphology. The experimental power of in vitro neuronal cultures to assay this process and its molecular mechanisms is well established, however, a method to rapidly find and quantify multiple morphological aspects of GCs is lacking. To this end, we have developed a free, easy to use, and fully automated Fiji macro, Conographer, which accurately identifies and measures many morphological parameters of GCs in 2D explant culture images. These measurements are then subjected to principle component analysis and k-means clustering to mathematically classify the GCs as "collapsed" or "extended". The morphological parameters measured for each GC are found to be significantly different between collapsed and extended GCs, and are sufficient to classify GCs as such with the same level of accuracy as human observers. Application of a known collapse-inducing ligand results in significant changes in all parameters, resulting in an increase in 'collapsed' GCs determined by k-means clustering, as expected. Our strategy provides a powerful tool for exploring the relationship between GC morphology and guidance cue signaling, which in particular will greatly facilitate high-throughput studies of the effects of drugs, gene silencing or overexpression, or any other experimental manipulation in the context of an in vitro axon guidance assay.

EMMPRIN, an upstream regulator of MMPs, in CNS biology.

Science.gov (United States)

Kaushik, Deepak Kumar; Hahn, Jennifer Nancy; Yong, V Wee

2015-01-01

Matrix metalloproteinases (MMPs) are engaged in pathologies associated with infections, tumors, autoimmune disorders and neurological dysfunctions. With the identification of an upstream regulator of MMPs, EMMPRIN (Extracellular matrix metalloproteinase inducer, CD147), it is relevant to address if EMMPRIN plays a role in the pathology of central nervous system (CNS) diseases. This would enable the possibility of a more upstream and effective therapeutic target. Indeed, conditions including gliomas, Alzheimer's disease (AD), multiple sclerosis (MS), and other insults such as hypoxia/ischemia show elevated levels of EMMPRIN which correlate with MMP production. In contrast, given EMMPRIN's role in CNS homeostasis with respect to regulation of monocarboxylate transporters (MCTs) and interactions with adhesion molecules including integrins, we need to consider that EMMPRIN may also serve important regulatory or protective functions. This review summarizes the current understanding of EMMPRIN's involvement in CNS homeostasis, its possible roles in escalating or reducing neural injury, and the mechanisms of EMMPRIN including and apart from MMP induction. Copyright © 2015 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

CRALBP supports the mammalian retinal visual cycle and cone vision

OpenAIRE

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

2015-01-01

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 ad...

CNS effects following the treatment of malignancy

International Nuclear Information System (INIS)

Rane, N.; Quaghebeur, G.

2012-01-01

Corporeal and central nervous system (CNS) axis chemotherapy and radiotherapy have long been used for the effective treatment and prophylaxis of CNS, body malignancies, and leukaemias. However, they are not without their problems. Following the proliferation of magnetic resonance neuroimaging in recent years it has become clear that the spectrum of toxicity that these therapies produce ranges from subclinical white matter changes to overt brain necrosis. The effects are both direct and indirect and via different pathological mechanisms. Chronic and progressive changes can be detected many years after the initial intervention. In addition to leucoencephalopathic changes, grey matter changes are now well described. Changes may be difficult to distinguish from tumour recurrence, though may be reversible and remediable, and are thus very important to differentiate. In this review toxic effects are classified and their imaging appearances discussed, with reference to specific syndromes.

Therapeutic potential of agmatine for CNS disorders.

Science.gov (United States)

Neis, Vivian B; Rosa, Priscila B; Olescowicz, Gislaine; Rodrigues, Ana Lúcia S

2017-09-01

Agmatine is a neuromodulator that regulates multiple neurotransmitters and signaling pathways. Several studies have focused on elucidating the mechanisms underlying the neuroprotective effects of this molecule, which seems to be mediated by a reduction in oxidative damage, neuroinflammation, and proapoptotic signaling. Since these events are implicated in acute and chronic excitotoxicity-related disorders (ischemia, epilepsy, traumatic brain injury, spinal cord injury, neurodegenerative, and psychiatric disorders) as well as in nociception, agmatine has been proposed as a therapeutic strategy for the treatment of central nervous system (CNS) disorders. Agmatine also stimulates the expression of trophic factors and adult neurogenesis, contributing to its ability to induce endogenous repair mechanisms. Therefore, considering its wide range of biological effects, this review summarizes the current knowledge about its protective and regenerative properties in the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mechanisms of CNS invasion and damage by parasites.

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Kristensson, Krister; Masocha, Willias; Bentivoglio, Marina

2013-01-01

Invasion of the central nervous system (CNS) is a most devastating complication of a parasitic infection. Several physical and immunological barriers provide obstacles to such an invasion. In this broad overview focus is given to the physical barriers to neuroinvasion of parasites provided at the portal of entry of the parasites, i.e., the skin and epithelial cells of the gastrointestinal tract, and between the blood and the brain parenchyma, i.e., the blood-brain barrier (BBB). A description is given on how human pathogenic parasites can reach the CNS via the bloodstream either as free-living or extracellular parasites, by embolization of eggs, or within red or white blood cells when adapted to intracellular life. Molecular mechanisms are discussed by which parasites can interact with or pass across the BBB. The possible targeting of the circumventricular organs by parasites, as well as the parasites' direct entry to the brain from the nasal cavity through the olfactory nerve pathway, is also highlighted. Finally, examples are given which illustrate different mechanisms by which parasites can cause dysfunction or damage in the CNS related to toxic effects of parasite-derived molecules or to immune responses to the infection. Copyright © 2013 Elsevier B.V. All rights reserved.

Effectiveness of Prescription-Based CNS Stimulants on Hospitalization in Patients With Schizophrenia

DEFF Research Database (Denmark)

Rohde, Christopher; Polcwiartek, Christoffer; Asztalos, Marton

2018-01-01

were used to investigate the effectiveness of CNS stimulants in patients with schizophrenia between 1995 and 2014; a mirror-image model with 605 individuals, using paired t tests and Wilcoxon signed rank tests, and a follow-up study with 789 individuals, using a conditional risk-set model. RESULTS: CNS...

Heavy-to-light correlators beyond the light cone

International Nuclear Information System (INIS)

Lucha, W.; Melikhov, D. I.; Simula, S.

2008-01-01

We present the first systematic analysis of the off-light-cone effects in correlators relevant for the extraction of the heavy-to-light form factors within the method of light-cone sum rules. In a model with scalar constituents, the correlator is calculated in two different ways: (i) by performing the expansion of the Bethe-Salpeter amplitude of the light meson near the light cone x 2 = 0 and (ii) by adopting the known solution for the Bethe-Salpeter amplitude which allows one to calculate the correlator without invoking any expansion. We demonstrate that the contributions to the correlator from the off-light-cone terms x 2 ≠ 0 are not suppressed by any large parameter compared to the contribution of the light-cone term x 2 0. For decays of heavy particles of mass in the range 1.5-5 GeV, the light-cone correlator is shown to systematically overestimate the full correlator, numerically the difference being 10-20%

Heavy-to-light correlators beyond the light cone

International Nuclear Information System (INIS)

Lucha, W.; Melikhov, D. I.; Simula, S.

2008-01-01

We present the first systematic analysis of the off-light-cone effects in correlators relevant for the extraction of the heavy-to-light form factors within the method of light-cone sum rules. In a model with scalar constituents, the correlator is calculated in two different ways: (i) by performing the expansion of the Bethe-Salpeter amplitude of the light meson near the light cone x 2 = 0 and (ii) by adopting the known solution for the Bethe-Salpeter amplitude which allows one to calculate the correlator without invoking any expansion. We demonstrate that the contributions to the correlator from the off-light-cone terms x 2 ≠ 0 are not suppressed by any large parameter compared to the contribution of the light-cone term x 2 = 0. For decays of heavy particles of mass in the range 1.5–5 GeV, the light-cone correlator is shown to systematically overestimate the full correlator, numerically the difference being 10–20%.

Strain engineering of Dirac cones in graphyne

Energy Technology Data Exchange (ETDEWEB)

Wang, Gaoxue; Kumar, Ashok; Pandey, Ravindra, E-mail: pandey@mtu.edu [Department of Physics, Michigan Technological University, Houghton, Michigan 49931 (United States); Si, Mingsu [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

2014-05-26

6,6,12-graphyne, one of the two-dimensional carbon allotropes with the rectangular lattice structure, has two kinds of non-equivalent anisotropic Dirac cones in the first Brillouin zone. We show that Dirac cones can be tuned independently by the uniaxial compressive strain applied to graphyne, which induces n-type and p-type self-doping effect, by shifting the energy of the Dirac cones in the opposite directions. On the other hand, application of the tensile strain results into a transition from gapless to finite gap system for the monolayer. For the AB-stacked bilayer, the results predict tunability of Dirac-cones by in-plane strains as well as the strain applied perpendicular to the plane. The group velocities of the Dirac cones show enhancement in the resistance anisotropy for bilayer relative to the case of monolayer. Such tunable and direction-dependent electronic properties predicted for 6,6,12-graphyne make it to be competitive for the next-generation electronic devices at nanoscale.

Plate Tearing by a Cone

DEFF Research Database (Denmark)

Simonsen, Bo Cerup

1997-01-01

The present paper is concerned with steady-state plate tearing by a cone. This is a scenario where a cone is forced through a ductile metal plate with a constant lateral tip penetration in a motion in the plane of the plate. The considered process could be an idealisaton of the damage, which...... as for the out-of-plane reaction force....

Three-dimensional evaluation of pharyngeal airway in individuals with varying growth patterns using cone beam computed tomography

Directory of Open Access Journals (Sweden)

Rohan Diwakar

2015-01-01

Full Text Available Introduction: The purpose of this study was to evaluate the pharyngeal airway volume in individuals with different vertical growth patterns. Methods: Cone beam computed tomography scans were evaluated of 40 subjects with the age range from 14 to 25 years and were divided into three groups. Horizontal growers consisted of 13 subjects, normal growers consisted of 14 subjects, and the vertical growers consisted of 13 subjects. The pharyngeal airway volume was measured using In Vivo Dental 5.1 software (Anatomage, Anatomy Imaging Software, San Jose, CA, USA. Results: The results obtained were analyzed statistically. The statistical test used for the analysis of the result was Student′s t-test. The independent t-test was done to compare the mean of the pharyngeal airway between the normal growers and horizontal growers and between the normal growers and the vertical growers. No statistically significant difference between the three groups was found in the volumetric measurements of the various sections of airway. Conclusions: Pharyngeal airway volume does not differ significantly in different vertical jaw relationships. It was possible to evaluate the pharyngeal airway volume three dimensionally.

Current approaches to enhance CNS delivery of drugs across the brain barriers

Directory of Open Access Journals (Sweden)

Lu CT

2014-05-01

Full Text Available Cui-Tao Lu,1 Ying-Zheng Zhao,2,3 Ho Lun Wong,4 Jun Cai,5 Lei Peng,2 Xin-Qiao Tian1 1The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou City, Zhejiang Province, People’s Republic of China; 2Hainan Medical College, Haikou City, Hainan Province, People’s Republic of China; 3College of Pharmaceutical Sciences, Wenzhou Medical University, Zhejiang Province, People’s Republic of China; 4School of Pharmacy, Temple University, Philadelphia, PA, USA; 5Departments of Pediatrics and Anatomical Sciences and Neurobiology, University of Louisville School of Medicine Louisville, KY, USA Abstract: Although many agents have therapeutic potentials for central nervous system (CNS diseases, few of these agents have been clinically used because of the brain barriers. As the protective barrier of the CNS, the blood–brain barrier and the blood–cerebrospinal fluid barrier maintain the brain microenvironment, neuronal activity, and proper functioning of the CNS. Different strategies for efficient CNS delivery have been studied. This article reviews the current approaches to open or facilitate penetration across these barriers for enhanced drug delivery to the CNS. These approaches are summarized into three broad categories: noninvasive, invasive, and miscellaneous techniques. The progresses made using these approaches are reviewed, and the associated mechanisms and problems are discussed. Keywords: drug delivery system, blood–brain barrier (BBB, central nervous system, brain-targeted therapy, cerebrospinal fluid (CSF

DOS cones along atomic chains

International Nuclear Information System (INIS)

Kwapiński, Tomasz

2017-01-01

The electron transport properties of a linear atomic chain are studied theoretically within the tight-binding Hamiltonian and the Green’s function method. Variations of the local density of states (DOS) along the chain are investigated. They are crucial in scanning tunnelling experiments and give important insight into the electron transport mechanism and charge distribution inside chains. It is found that depending on the chain parity the local DOS at the Fermi level can form cone-like structures (DOS cones) along the chain. The general condition for the local DOS oscillations is obtained and the linear behaviour of the local density function is confirmed analytically. DOS cones are characterized by a linear decay towards the chain which is in contrast to the propagation properties of charge density waves, end states and Friedel oscillations in one-dimensional systems. We find that DOS cones can appear due to non-resonant electron transport, the spin–orbit scattering or for chains fabricated on a substrate with localized electrons. It is also shown that for imperfect chains (e.g. with a reduced coupling strength between two neighboring sites) a diamond-like structure of the local DOS along the chain appears. (paper)

DOS cones along atomic chains

Science.gov (United States)

Kwapiński, Tomasz

2017-03-01

The electron transport properties of a linear atomic chain are studied theoretically within the tight-binding Hamiltonian and the Green’s function method. Variations of the local density of states (DOS) along the chain are investigated. They are crucial in scanning tunnelling experiments and give important insight into the electron transport mechanism and charge distribution inside chains. It is found that depending on the chain parity the local DOS at the Fermi level can form cone-like structures (DOS cones) along the chain. The general condition for the local DOS oscillations is obtained and the linear behaviour of the local density function is confirmed analytically. DOS cones are characterized by a linear decay towards the chain which is in contrast to the propagation properties of charge density waves, end states and Friedel oscillations in one-dimensional systems. We find that DOS cones can appear due to non-resonant electron transport, the spin-orbit scattering or for chains fabricated on a substrate with localized electrons. It is also shown that for imperfect chains (e.g. with a reduced coupling strength between two neighboring sites) a diamond-like structure of the local DOS along the chain appears.

When the Tail Can't Wag the Dog: The Implications of CNS-Intrinsic Initiation of Neuroinflammation

Directory of Open Access Journals (Sweden)

Deirdre S Davis

2009-04-01

Full Text Available The CNS (central nervous system is unquestionably the central organ that regulates directly or indirectly all physiological systems in the mammalian body. Yet, when considering the defence of the CNS from pathogens, the CNS has often been considered passive and subservient to the pro-inflammatory responses of the immune system. In this view, neuroinflammatory disorders are examples of when the tail (the immune system wags the dog (the CNS to the detriment of an individual's function and survival.

Hanford waste tank cone penetrometer

International Nuclear Information System (INIS)

Seda, R.Y.

1995-12-01

A new tool is being developed to characterize tank waste at the Hanford Reservation. This tool, known as the cone penetrometer, is capable of obtaining chemical and physical properties in situ. For the past 50 years, this tool has been used extensively in soil applications and now has been modified for usage in Hanford Underground Storage tanks. These modifications include development of new ''waste'' data models as well as hardware design changes to accommodate the hazardous and radioactive environment of the tanks. The modified cone penetrometer is scheduled to be deployed at Hanford by Fall 1996. At Hanford, the cone penetrometer will be used as an instrumented pipe which measures chemical and physical properties as it pushes through tank waste. Physical data, such as tank waste stratification and mechanical properties, is obtained through three sensors measuring tip pressure, sleeve friction and pore pressure. Chemical data, such as chemical speciation, is measured using a Raman spectroscopy sensor. The sensor package contains other instrumentation as well, including a tip and side temperature sensor, tank bottom detection and an inclinometer. Once the cone penetrometer has reached the bottom of the tank, a moisture probe will be inserted into the pipe. This probe is used to measure waste moisture content, water level, waste surface moisture and tank temperature. This paper discusses the development of this new measurement system. Data from the cone penetrometer will aid in the selection of sampling tools, waste tank retrieval process, and addressing various tank safety issues. This paper will explore various waste models as well as the challenges associated with tank environment

Distributed pubertal growth in girls after acute leukemia: a relative growth hormone insufficiency with late presentation

Energy Technology Data Exchange (ETDEWEB)

Moell, C.

1988-01-01

Long-term follow-up of growth and development after acute lymphoblastic leukaemia (ALL) in childhood has previously been limited to the prepubertal period. This study describes pubertal growth, final height and the spontaneous secretion of GH in girls treated for ALL, including CNS irradiation with 24 GY. Ten girls, treated earlier for ALL, experienced the menarche at a mean age of 12.2 years. This is significantly earlier than the mean for Swedish girls. Prepubertal growth was near normal after the end of therapy for leukaemia. Mean final height was -1.7 SD, which is 1.5 SD less than at onset and 1.0 SD less than 1 year after the end of treatment. Thirteen other girls had a blunted spontaneous secretion of GH, several years after treatment for ALL; there was no increase in GH secretion during puberty. These results suggest that girls who have been treated for ALL, including CNS irradiation, have a relative GH insufficiency. This insufficiency becomes obvious only when girls cannot respond to the increased need for GH during the pubertal spurt.

Distributed pubertal growth in girls after acute leukemia: a relative growth hormone insufficiency with late presentation

International Nuclear Information System (INIS)

Moell, C.

1988-01-01

Long-term follow-up of growth and development after acute lymphoblastic leukaemia (ALL) in childhood has previously been limited to the prepubertal period. This study describes pubertal growth, final height and the spontaneous secretion of GH in girls treated for ALL, including CNS irradiation with 24 GY. Ten girls, treated earlier for ALL, experienced the menarche at a mean age of 12.2 years. This is significantly earlier than the mean for Swedish girls. Prepubertal growth was near normal after the end of therapy for leukaemia. Mean final height was -1.7 SD, which is 1.5 SD less than at onset and 1.0 SD less than 1 year after the end of treatment. Thirteen other girls had a blunted spontaneous secretion of GH, several years after treatment for ALL; there was no increase in GH secretion during puberty. These results suggest that girls who have been treated for ALL, including CNS irradiation, have a relative GH insufficiency. This insufficiency becomes obvious only when girls cannot respond to the increased need for GH during the pubertal spurt. (author)

Nootropic, anxiolytic and CNS-depressant studies on different plant sources of shankhpushpi.

Science.gov (United States)

Malik, Jai; Karan, Maninder; Vasisht, Karan

2011-12-01

Shankhpushpi, a well-known drug in Ayurveda, is extensively used for different central nervous system (CNS) effects especially memory enhancement. Different plants are used under the name shankhpushpi in different regions of India, leading to an uncertainty regarding its true source. Plants commonly used under the name shankhpushpi are: Convolvulus pluricaulis Chois., Evolvulus alsinoides Linn., both from Convolvulaceae, and Clitoria ternatea Linn. (Leguminosae). To find out the true source of shankhpushpi by evaluating and comparing memory-enhancing activity of the three above mentioned plants. Anxiolytic, antidepressant and CNS-depressant activities of these three plants were also compared and evaluated. The nootropic activity of the aqueous methanol extract of each plant was tested using elevated plus-maze (EPM) and step-down models. Anxiolytic, antidepressant and CNS-depressant studies were evaluated using EPM, Porsolt?s swim despair and actophotometer models, respectively. C. pluricaulis extract (CPE) at a dose of 100 mg/kg, p.o. showed maximum nootropic and anxiolytic activity (p nootropic, anxiolytic and CNS-depressant activity. The results of memory-enhancing activity suggest C. pluricaulis to be used as true source of shankhpushpi.

Chemical composition and antimicrobial activity of essential oil from cones of Pinus koraiensis.

Science.gov (United States)

Lee, Jeong-Ho; Yang, Hye-Young; Lee, Hong-Sub; Hong, Soon-Kwang

2008-03-01

The essential oil from the cones of Pinus koraiensis was prepared after removing the seeds, and its chemical composition analyzed using gas chromatography-mass spectrometry (GC-MS). Hydrodistillation of the P. koraiensis cones yielded 1.07% (v/w) of essential oil, which was almost three times the amount of essential oil extracted from the needles of the same plant. Moreover, the antimicrobial activities of the oil against the growth of Gram-positive bacteria, Gram-negative bacteria, and fungi were evaluated using the agar disc diffusion method and broth microdilution method. Eighty-seven components, comprising about 96.8% of the total oil, were identified. The most abundant oil components were limonene (27.90%), alpha-pinene (23.89%), beta-pinene (12.02%), 3-carene (4.95%), beta-myrcene (4.53%), isolongifolene (3.35%), (-)-bornyl acetate (2.02%), caryophyllene (1.71%), and camphene (1.54%). The essential oil was confirmed to have significant antimicrobial activities, especially against pathogenic fungal strains such as Candida glabrata YFCC 062 and Cryptococcus neoformans B 42419. Therefore, the present results indicate that the essential oil from the cones of Pinus koraiensis can be used in various ways as a nontoxic and environmentally friendly disinfectant.

Glucocorticoid treatment of MCMV infected newborn mice attenuates CNS inflammation and limits deficits in cerebellar development.

Directory of Open Access Journals (Sweden)

Kate Kosmac

2013-03-01

Full Text Available Infection of the developing fetus with human cytomegalovirus (HCMV is a major cause of central nervous system disease in infants and children; however, mechanism(s of disease associated with this intrauterine infection remain poorly understood. Utilizing a mouse model of HCMV infection of the developing CNS, we have shown that peripheral inoculation of newborn mice with murine CMV (MCMV results in CNS infection and developmental abnormalities that recapitulate key features of the human infection. In this model, animals exhibit decreased granule neuron precursor cell (GNPC proliferation and altered morphogenesis of the cerebellar cortex. Deficits in cerebellar cortical development are symmetric and global even though infection of the CNS results in a non-necrotizing encephalitis characterized by widely scattered foci of virus-infected cells with mononuclear cell infiltrates. These findings suggested that inflammation induced by MCMV infection could underlie deficits in CNS development. We investigated the contribution of host inflammatory responses to abnormal cerebellar development by modulating inflammatory responses in infected mice with glucocorticoids. Treatment of infected animals with glucocorticoids decreased activation of CNS mononuclear cells and expression of inflammatory cytokines (TNF-α, IFN-β and IFNγ in the CNS while minimally impacting CNS virus replication. Glucocorticoid treatment also limited morphogenic abnormalities and normalized the expression of developmentally regulated genes within the cerebellum. Importantly, GNPC proliferation deficits were normalized in MCMV infected mice following glucocorticoid treatment. Our findings argue that host inflammatory responses to MCMV infection contribute to deficits in CNS development in MCMV infected mice and suggest that similar mechanisms of disease could be responsible for the abnormal CNS development in human infants infected in-utero with HCMV.

The shifting landscape of metastatic breast cancer to the CNS.

Science.gov (United States)

Quigley, Matthew R; Fukui, Olivia; Chew, Brandon; Bhatia, Sanjay; Karlovits, Steven

2013-07-01

The improved survival following the diagnosis of breast cancer has potentially altered the characteristics and course of patients presenting with CNS involvement. We therefore sought to define our current cohort of breast cancer patients with metastatic disease to the CNS in regard to modern biomarkers and clinical outcome. Review of clinical and radiographic records of women presenting to a tertiary medical center with the new diagnosis of CNS metastatic disease from breast cancer. This was a retrospective review from patients identities obtained from two prospective databases. There were 88 women analyzed who were treated over the period of January 2003 to February 2010, average age 56.9 years. At the time of initial presentation of CNS disease, 68 % of patients had multiple brain metastases, 17 % had a solitary metastasis, and 15 % had only leptomeningeal disease (LMD). The median survival for all patients from the time of diagnosis of breast disease was 50.0 months, and 9.7 months from diagnosis of CNS involvement. The only factor related to overall survival was estrogen receptor-positive pathology (57.6 v. 38.2 months, p = .02 log-rank); those related to survival post CNS diagnosis were presentation with LMD (p = .004, HR = 3.1, Cox regression) and triple-negative hormonal/HER2 status (p = .02, HR = 2.3, Cox regression). Patients with either had a median survival of 3.1 months (no patients in common). Of the 75 patients who initially presented with metastatic brain lesions, 20 (26 %) subsequently developed LMD in the course of their disease (median 10.4 months), following which survival was grim (1.8 months median). Symptoms of LMD were most commonly lower extremity weakness (14/33), followed by cranial nerve deficits (11/33). The recently described Graded Prognostic Assessment (GPA) tumor index stratified median survival at 2.5, 5.9, 13.1, and 21.7 months, respectively, for indices of 1-4 (p = .004, log-rank), which

Influence of mercury and CNS irradation upon the dynamics of the skeletal musculature

International Nuclear Information System (INIS)

Johnson, R.M.

1981-01-01

The existence of different mechanisms of central nervous system damage from CNS irradiation and chronic mercurial poisoning implies a possible synergism of effect from the two insults. In order to determine the level of hazard from this combined insult, a two way treatment was given to twelve groups of female Holtzman rats. The mortality data yield the surprising result that CNS irradiation has the effect of marginally extending the life of mercury poisoned rats. The work output versus time revealed that rats reach their maximum work output of about 2.5 millihorsepower at about one year of age. Rats with zero and low mercury give about the same maximal work output patterns. Those who have been ingesting 25 ppM are feeble, putting out around 10 microhorsepower. The only apparent effect of radiation is a drop in work output at about one year of age for the 5000 R rats. The effect of experimental insult upon the growth and weight patterns of the rats differed with their mercury level, while the effect of their irradiation status was of less importance. It is to be noted that over all the characteristics observed, the combined insults of radiation and mercurialism produced not synergism of effect. In fact, there are indications in several places that the effects of the insults are actually antagonistic

Plate Tearing by a Cone

DEFF Research Database (Denmark)

Simonsen, Bo Cerup

1998-01-01

The present paper is concerned with steady-state plate tearing by a cone. This is a scenario where a cone is forced through a ductile metal plate with a constant lateral tip penetration in a motion in the plane of the plate. The considered process could be an idealisation of the damage, which...... as for the out-of-plane reaction force. (C) 1998 Elsevier Science Ltd. All rights reserved....

Topology-optimized dual-polarization Dirac cones

Science.gov (United States)

Lin, Zin; Christakis, Lysander; Li, Yang; Mazur, Eric; Rodriguez, Alejandro W.; Lončar, Marko

2018-02-01

We apply a large-scale computational technique, known as topology optimization, to the inverse design of photonic Dirac cones. In particular, we report on a variety of photonic crystal geometries, realizable in simple isotropic dielectric materials, which exhibit dual-polarization Dirac cones. We present photonic crystals of different symmetry types, such as fourfold and sixfold rotational symmetries, with Dirac cones at different points within the Brillouin zone. The demonstrated and related optimization techniques open avenues to band-structure engineering and manipulating the propagation of light in periodic media, with possible applications to exotic optical phenomena such as effective zero-index media and topological photonics.

Demise of light cone field theory

International Nuclear Information System (INIS)

Hagen, C.R.

1977-01-01

It is shown that the massive spin one-half field is noncovariant in two dimensional light cone coordinates. It is shown that spin one-half is noncovariant in four dimensions as well. It is concluded that since the case of the spin one-half field is an absolute necessity if one is to build a world containing fermions. It seems safe to infer that light cone quantization cannot be useful in the quark binding problem as currently conceived. It is suggested that further work on light cone quantization be focused solely upon the questions of consistency as discussed rather than on applications to model building. 9 references

Integrity of the cone photoreceptor mosaic in oligocone trichromacy

DEFF Research Database (Denmark)

Michaelides, Michel; Rha, Jungtae; Dees, Elise W

2011-01-01

Oligocone trichromacy (OT) is an unusual cone dysfunction syndrome characterized by reduced visual acuity, mild photophobia, reduced amplitude of the cone electroretinogram with normal rod responses, normal fundus appearance, and normal or near-normal color vision. It has been proposed that these...... that these patients have a reduced number of normal functioning cones (oligocone). This paper has sought to evaluate the integrity of the cone photoreceptor mosaic in four patients previously described as having OT....

The Rat Homolog of the Schizophrenia Susceptibility Gene ZNF804A Is Highly Expressed during Brain Development, Particularly in Growth Cones

DEFF Research Database (Denmark)

Hinna, Katja Hvid; Rich, Karen; Fex Svenningsen, Åsa

2015-01-01

it decreases towards adult levels. This time point is developmentally the equivalent to the second trimester of fetal development in humans. An exception to this expression pattern is the hippocampus where the expression of Zfp804A appears to increase again in the adult brain. Using laser capture...... developmental mechanisms are suggested in the pathophysiology for schizophrenia, expression of Zfp804A, the rat homolog of ZNF804A, was investigated in the developing rat brain. We found that expression of Zfp804A in most brain regions is developmentally regulated and peaks around birth, where after...... expression was therefore investigated with immunochemistry in such cultures. Interestingly, before day 4, the protein is mostly found in the perinuclear region of the cell but at day 4, ZFP804A was instead found throughout the cell and particularly in the growth cones. In conclusion we demonstrate that Zfp...

Ketamine displaces the novel NMDA receptor SPET probe [123I]CNS-1261 in humans in vivo

International Nuclear Information System (INIS)

Stone, James M.; Erlandsson, Kjell; Arstad, Erik; Bressan, Rodrigo A.; Squassante, Lisa; Teneggi, Vincenza; Ell, Peter J.; Pilowsky, Lyn S.

2006-01-01

[ 123 I]CNS-1261 [N-(1-naphthyl)-N'-(3-iodophenyl)-N-methylguanidine] is a high-affinity SPET ligand with selectivity for the intrachannel PCP/ketamine/MK-801 site of the N-methyl-D-aspartate (NMDA) receptor. This study evaluated the effects of ketamine (a specific competitor for the intrachannel PCP/ketamine/MK-801 site) on [ 123 I]CNS-1261 binding to NMDA receptors in vivo. Ten healthy volunteers underwent 2 bolus-plus-infusion [ 123 I]CNS-1261 scans, one during placebo and the other during a ketamine challenge. Ketamine administration led to a significant decrease in [ 123 I]CNS-1261 V T in most of the brain regions examined (P 123 I]CNS-1261 appears to be a specific ligand in vivo for the intrachannel PCP/ketamine/MK-801 NMDA binding site

Embracing the future: Canada's nuclear renewal and growth. 28th annual conference of the Canadian Nuclear Society and 31st CNS/CNA student conference

International Nuclear Information System (INIS)

2007-01-01

The 28th Annual Conference of the Canadian Nuclear Society and 31st CNS/CNA Student Conference was held on June 3-6, 2007 in Saint John, New Brunswick. The central objective of this conference was to provide a forum for exchange of views on how this technical enterprise can best serve the needs of humanity, now and in the future. 'Embracing the Future: Canada's Nuclear Renewal and Growth' was the theme for this year's gathering of nuclear industry experts from across Canada and around the world. This theme reflects the global renaissance of interest in nuclear technology, strongly evident here in Canada through plant refurbishments (underway and planned), new-build planning, renewal and expansion of the nuclear workforce, and growth in public support for environmentally sustainable technology. Topics for discussion at this conference include: the nuclear renaissance in Canada and around the world, recent developments at Canadian utilities, status of plant refurbishment and new build plans, and uranium supply issues. For business, energy, and science reporters this conference offers an insight into major nuclear projects and an opportunity to meet leaders in the nuclear sector. Over 100 technical papers were presented, as well as over 20 student papers, in the following sessions: control room operation; safety analyses; environment and waste management; plant life management and refurbishment; reactor physics; advanced reactor design; instrumentation control; general nuclear topics and standards; chemistry and materials; probabilistic safety assessment; and, performance improvement

[11C]NS8880, a promising PET radiotracer targeting the norepinephrine transporter

DEFF Research Database (Denmark)

Vase, Karina Højrup; Peters, Dan; Nielsen, Elsebeth Ø

2014-01-01

-azabicyclo[3.2.1]octane (NS8880), targeting NET. NS8880 has an in vitro binding profile comparable to desipramine and is structurally not related to reboxetine. METHODS: Labeling of NS8880 with [11C] was achieved by a non-conventional technique: substitution of pyridinyl fluorine with [11C]methanolate...... yields with high purity. The PET in vivo evaluation in pig and rat revealed a rapid brain uptake of [11C]NS8880 and fast obtaining of equilibrium. Highest binding was observed in thalamic and hypothalamic regions. Pretreatment with desipramine efficiently reduced binding of [11C]NS8880. CONCLUSION: Based...... on the pre-clinical results obtained so far [11C]NS8880 displays promising properties for PET imaging of NET....

CRYOVOLCANISM AND THE MYSTERY OF THE PATOM CONE

Directory of Open Access Journals (Sweden)

Vladimir R. Alekseyev

2012-01-01

Full Text Available In the Earth’s regions with cold climate, cryovolcanism is widespread. This phenomena is manifested as eruptions of material due to freezing of closed-type or open-type water-bearing systems which is accompanied by generation of effusive topographic forms, such as «pingo». The Patom cone is a typical structure created by cryovolcanism in fractured bedrocksof the Proterozoic age. The cone was shaped a result of the long-term, possibly multistage freezing of the hydrogeological structure during continuous and complicated phase of cryo- and speleo-genesis. The ice-saturated breccia containing limestone, sandstone and shale, which composed the cone, was subject to slow spreading due to its plastic properties; the top of the mound developed into a subsidence cone bordered by ring-shaped ramparts and a knoll in the middle, while thelongitudinal profile took on an asymmetric form. The absence of soil and vegetation cover on the surface of the cone, and a relatively weak degree of weathering of the rudaceous deposits bear no evidence that the geological object is young. The question as to the age of the cone is still open.

A reconstruction algorithms for helical cone-beam SPECT

International Nuclear Information System (INIS)

Weng, Y.; Zeng, G.L.; Gullberg, G.T.

1993-01-01

Cone-beam SPECT provides improved sensitivity for imaging small organs like the brain and heart. However, current cone-beam tomography with the focal point traversing a planar orbit does not acquire sufficient data to give an accurate reconstruction. In this paper, the authors employ a data-acquisition method which obtains complete data for cone-beam SPECT by simultaneously rotating the gamma camera and translating the patient bed, so that cone-beam projections can be obtained with the focal point traversing a helix surrounding the patient. An implementation of Grangeat's algorithm for helical cone-beam projections is developed. The algorithm requires a rebinning step to convert cone-beam data to parallel-beam data which are then reconstructed using the 3D Radon inversion. A fast new rebinning scheme is developed which uses all of the detected data to reconstruct the image and properly normalizes any multiply scanned data. This algorithm is shown to produce less artifacts than the commonly used Feldkamp algorithm when applied to either a circular planar orbit or a helical orbit acquisition. The algorithm can easily be extended to any arbitrary orbit

Morphological evaluation of fetus CNS and its related anomalies

International Nuclear Information System (INIS)

Oi, Shizuo; Tamaki, Norihiko; Matsumoto, Satoshi; Katayama, Kazuaki; Mochizuki, Matsuto

1989-01-01

The fetus central nervous system was evaluated morphologically by ultrasonography (US), magnetic resonance imaging (MRI), and CT scan to analyze the prenatal diagnostic value for CNS anomalies. A total of 31 patients with 42 lesions had been diagnosed during the preceding 7 years. The patients included 24 with hydrocephalus, three with anencephaly, three with myeloschisis, three with holoprosencephaly, three with an encephalocele, two with a Dandy-Walker cyst, one with hydroencephalodysplasia, one with an intracranial neoplasm, one with sacrococcygeal teratoma, and one with sacral agenesis. Compared with US and MRI, CT proved to be more accurate in the detection of spine and cranium-bone morphology. This finding seems to be valuable in the diagnosis of spina bifida, cranium bifidum and some cases of hypertensive hydrocephalus, especially in the axial view. MRI was definitely superior in the anatomico-pathological diagnosis of cerebral dysgenesis, ventriculomegaly, intracranial tumors, and other brain parenchymal changes in view of multi-dimensional analysis. The most considerable disadvantage of MRI in the diagnosis of a fetus CNS anomaly is the poor information about spine and cranium morphology. A super-conducting MRI system is still insufficient to demonstrate the spinal cord of a fetus. US was routinely used, and the multidimensional slices were useful for screening the CNS abnormalies. Some of the fetus brain lesions, such as intracranial hematomas, had a specific echogenecity on US. However, US sometimes failed to demarcate the cerebral parenchymal or subdural morphological changes because its artifacts had hyperchoic shadows. While US, MRI, and CT were valuable diagnostic tools in the morphological evaluation of fetus CNS and its related anomalies, each modality has different diagnostic advantages and disadvantages. Improvement can be expected when these diagnostic imaging modalities are complementary, depending upon the nature of the anatomy. (J.P.N.)

Analysis of neurocognitive function and CNS endpoints in the PROTEA trial

DEFF Research Database (Denmark)

Clarke, Amanda; Johanssen, Veronika; Gerstoft, Jan

2014-01-01

INTRODUCTION: During treatment with protease inhibitor monotherapy, the number of antiretrovirals with therapeutic concentrations in the cerebrospinal fluid (CSF) is lower, compared to standard triple therapy. However, the clinical consequences are unclear. METHODS: A total of 273 patients with HIV...... and the Grooved Pegboard Test at screening, baseline and at Week 48. A global neurocognitive score (NPZ-5) was derived by averaging the standardized results of the five domains. In a central nervous system (CNS) sub-study (n=70), HIV RNA levels in the CNS were evaluated at baseline and Week 48. Clinical adverse...... events related to the CNS were collected at each visit. RESULTS: Patients were 83% male and 88% White, with median age 43 years. There were more patients with nadir CD4 count below 200 cells/µL in the DRV/r monotherapy arm (41/137, 30%) than the triple therapy arm (30/136, 22%). At Week 48...

Integrity of the cone photoreceptor mosaic in oligocone trichromacy

DEFF Research Database (Denmark)

Michaelides, Michel; Rha, Jungtae; Dees, Elise W

2011-01-01

Oligocone trichromacy (OT) is an unusual cone dysfunction syndrome characterized by reduced visual acuity, mild photophobia, reduced amplitude of the cone electroretinogram with normal rod responses, normal fundus appearance, and normal or near-normal color vision. It has been proposed that these......Oligocone trichromacy (OT) is an unusual cone dysfunction syndrome characterized by reduced visual acuity, mild photophobia, reduced amplitude of the cone electroretinogram with normal rod responses, normal fundus appearance, and normal or near-normal color vision. It has been proposed...

Simulation analysis of the effects of an initial cone position and opening angle on a cone-guided implosion

Energy Technology Data Exchange (ETDEWEB)

Yanagawa, T. [Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan); Sakagami, H. [Fundamental Physics Simulation Division, National Institute for Fusion Science, Oroshi-cho, Toki, Gifu 509-5292 (Japan); Nagatomo, H. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)

2013-10-15

In inertial confinement fusion, the implosion process is important in forming a high-density plasma core. In the case of a fast ignition scheme using a cone-guided target, the fuel target is imploded with a cone inserted. This scheme is advantageous for efficiently heating the imploded fuel core; however, asymmetric implosion is essentially inevitable. Moreover, the effect of cone position and opening angle on implosion also becomes critical. Focusing on these problems, the effect of the asymmetric implosion, the initial position, and the opening angle on the compression rate of the fuel is investigated using a three-dimensional pure hydrodynamic code.

[Non-structural abnormalities of CNS function resulting in coincidence of endocrinopathies, epilepsy and psychoneurologic disorders in children and adolescents].

Science.gov (United States)

Starzyk, Jerzy; Pituch-Noworolska, Anna; Pietrzyk, Jacek A; Urbanik, Andrzej; Kroczka, Sławomir; Drozdz, Ryszard; Wójcik, Małgorzata

2010-01-01

In the population of children and adolescents, epilepsy affects approximately 1% of cases, nonepileptic seizures are seen in approximately 3%, and endocrine disorders are several times more common. For this reason, coincidence of endocrine disorders and epilepsy and psychoneurologic disorders is frequent. Much less common are structural abnormalities (tumors, developmental abnormalities), and especially non-structural CNS abnormalities, resulting in coincidence of both disorders. There are no reports available in the literature that would address the problem. 1) Assessment of the frequency of coincidental epilepsy and endocrine disorders in patients without structural CSN abnormalities treated as outpatients and inpatients of Department of Endocrinology University Children's Hospital of Krakow. 2) Presentation of diagnostic and therapeutic difficulties in these patients, and 3) An attempt at defining the common etiology of both disorders. On the basis of ICD code patients with coincidance of endocrine disorders, epilepsy and psychoneurologic disorders were selected from several thousands of children treated between 2000 and 2009 in Pediatric Endocrinology Department. The neurologic disorders were diagnosed and treated in Chair and Department of Children's and Adolescents Neurology or in another pediatric neurology center. Various forms of epilepsy (symptomatic or idiopathic) and other psychoneurological disorders (disorders of behavior and emotions, obsession-compulsion syndromes, stereotypias, aggression, autoaggression, or hypothalamic obesity) coincident with one or more endocrine disorders, such as growth disorders, disorders of pubertal development, obesity, thyroid diseases, adrenal diseases, hyperprolactinemia, hypoparathyroidism and ion metabolism disorders were diagnosed in 49 patients. The group included: i) children after cranial irradiation and chemotherapy due to medulloblastoma (3 patients), oligodenroglioma (1 patient), ependymoma (1 patient), optic

Nuclear innovation through collaboration. 35th Annual CNS conference and 39th CNS/CNA student conference

International Nuclear Information System (INIS)

2015-01-01

The Canadian Nuclear Society (CNS) held its 35th Annual Conference in Saint John, New Brunswick, Canada on May 31 to June 3, 2015, combined with the 39th Annual CNS/CNA Student Conference. With the theme of the conference, 'Nuclear Innovation through Collaboration', more than 425 delegates, exhibitors and students were in attendance. The conference commenced with two strong plenary sessions on Utility Collaborations to Improve Lifetime Performance; and, Performance Improvement Programs: Goals and Experience. The second day consisted of the panel discussions on International Developments in Used Nuclear Fuel Repository Programs, and two plenary sessions on: Enterprise Risk Management; and, Vendor Role in a Continuously Improving Industry. The third day contained a number of interesting features, including plenary sessions on Waste Management and Decommissioning; Developing Technologies and Resources, and a panel discussion on the Transportation of Used Nuclear Fuel. All three days of the conference also contained parallel sessions with over 100 technical papers presented at the main and student sessions. The technical session titles were: Refurbishment and Life Extension; Thermalhydraulics; Nuclear Materials; WMD - Radiation Monitoring; Safety and Licensing; Communication; Safety and Licensing; Instrumentation and Control; Advanced Reactor Designs; WMD - Deep Geological Repository Packaging; Reactor Physics; Chemistry and Materials; Advanced Fuel Cycles; Waste Management and Decommissioning; and, Medical Physics and Radiation Biology.

Cone penetrometer moisture probe acceptance test report

International Nuclear Information System (INIS)

Barnes, G.A.

1996-01-01

This Acceptance Test Report (ATR) documents the results of WHC-SD-WM-ATP-146 (Prototype Cone Penetrometer Moisture Probe Acceptance Test Procedure) and WHC-SD-WM-ATP-145 (Cone Penetrometer Moisture Probe Acceptance Test Procedure). The master copy of WHC-SD-WM-ATP-145 can be found in Appendix A and the master copy of WHC-SD-WM-ATP-146 can be found in Appendix B. Also included with this report is a matrix showing design criteria of the cone penetrometer moisture probe and the verification method used (Appendix C)

Techniques for optimizing nanotips derived from frozen taylor cones

Science.gov (United States)

Hirsch, Gregory

2017-12-05

Optimization techniques are disclosed for producing sharp and stable tips/nanotips relying on liquid Taylor cones created from electrically conductive materials with high melting points. A wire substrate of such a material with a preform end in the shape of a regular or concave cone, is first melted with a focused laser beam. Under the influence of a high positive potential, a Taylor cone in a liquid/molten state is formed at that end. The cone is then quenched upon cessation of the laser power, thus freezing the Taylor cone. The tip of the frozen Taylor cone is reheated by the laser to allow its precise localized melting and shaping. Tips thus obtained yield desirable end-forms suitable as electron field emission sources for a variety of applications. In-situ regeneration of the tip is readily accomplished. These tips can also be employed as regenerable bright ion sources using field ionization/desorption of introduced chemical species.

Metallothionein expression and roles in the CNS

DEFF Research Database (Denmark)

Penkowa, Milena

2002-01-01

  Metallothioneins (MTs) are low-molecular-weight (6-7 kDa) nonenzymatic proteins (60-68 amino acid residues, 25-30% being cysteine) expressed ubiquitous in the animal kingdom. In the central nervous system (CNS), three MT isoforms are known, namely MT-I to MT-III. MT-I and MT-II (MT...

An Analysis Model for Water Cone Subsidence in Bottom Water Drive Reservoirs

Science.gov (United States)

Wang, Jianjun; Xu, Hui; Wu, Shucheng; Yang, Chao; Kong, lingxiao; Zeng, Baoquan; Xu, Haixia; Qu, Tailai

2017-12-01

Water coning in bottom water drive reservoirs, which will result in earlier water breakthrough, rapid increase in water cut and low recovery level, has drawn tremendous attention in petroleum engineering field. As one simple and effective method to inhibit bottom water coning, shut-in coning control is usually preferred in oilfield to control the water cone and furthermore to enhance economic performance. However, most of the water coning researchers just have been done on investigation of the coning behavior as it grows up, the reported studies for water cone subsidence are very scarce. The goal of this work is to present an analytical model for water cone subsidence to analyze the subsidence of water cone when the well shut in. Based on Dupuit critical oil production rate formula, an analytical model is developed to estimate the initial water cone shape at the point of critical drawdown. Then, with the initial water cone shape equation, we propose an analysis model for water cone subsidence in bottom water reservoir reservoirs. Model analysis and several sensitivity studies are conducted. This work presents accurate and fast analytical model to perform the water cone subsidence in bottom water drive reservoirs. To consider the recent interests in development of bottom drive reservoirs, our approach provides a promising technique for better understanding the subsidence of water cone.

CNS Involvement in Hemophagocytic Lymphohistiocytosis: CT and MR Findings

International Nuclear Information System (INIS)

Chung, Tae Woong

2007-01-01

Hemophagocytic lymphohistiocytosis (HLH) is a rare disorder that is characterized by proliferation of benign histiocytes, and this commonly involves the liver, spleen, lymph nodes, bone marrow and central nervous system (CNS). We report here on the CT and MR imaging findings in a case of CNS HLH that showed multiple ring enhancing masses mimicking abscess or another mass on the CT and MR imaging. emophagocytic lymphohistiocytosis (HLH) is a rare disorder that is characterized by nonmalignant diffuse infiltration of multiple organs, including the central nervous system (CNS), by lymphocytes and histiocytes (1). Many radiologic reports describing diffuse white matter infiltrations, parenchymal atrophy and calcification have been published, but the characteristics of these findings remain non-specific, especially in immunocompromised patients. We present here a case of HLH in a 3-year-old boy who presented with multiple ring enhancing lesions involving the brain. In conclusion, although the CT and MRI findings of HLH with ring enhancing parenchymal lesions are nonspecific and mimic abscess, and especially in the immunosuppressed patients, increased diffusion at the center on DWI may be a finding of HLH to differentiate it from abscess, which has restricted diffusion at the center. However, the pathologic correlation with DWI according to the lesion stage certainly needs further study with a larger number of patients

Is risk of central nervous system (CNS) relapse related to adjuvant taxane treatment in node-positive breast cancer? Results of the CNS substudy in the intergroup Phase III BIG 02-98 Trial

DEFF Research Database (Denmark)

Pestalozzi, B.C.; Francis, P.; Quinaux, E.

2008-01-01

BACKGROUND: Breast cancer central nervous system (CNS) metastases are an increasingly important problem because of high CNS relapse rates in patients treated with trastuzumab and/or taxanes. PATIENTS AND METHODS: We evaluated data from 2887 node-positive breast cancer patients randomised in the BIG...

Cone Penetrometer N Factor Determination Testing Results

Energy Technology Data Exchange (ETDEWEB)

Follett, Jordan R.

2014-03-05

This document contains the results of testing activities to determine the empirical 'N Factor' for the cone penetrometer in kaolin clay simulant. The N Factor is used to releate resistance measurements taken with the cone penetrometer to shear strength.

Preparation of Au cone for fast ignition target

International Nuclear Information System (INIS)

Du Kai; Zhou Lan; Zhang Lin; Wan Xiaobo; Xiao Jiang

2005-01-01

Cone-shell target is typically used for the fast ignition experiments of inertial confinement fusion. In order to fabricate cone-shell target the Au cones with different angles were produced by electroplating and precise machining. The Au electroplating process was introduced in the paper, and the dependence of coating quality on the parameters, such as composition, temperature, pH of electroplating bath, current density and tip effect, were discussed. (author)

Contribution of Schwann Cells to Remyelination in a Naturally Occurring Canine Model of CNS Neuroinflammation.

Directory of Open Access Journals (Sweden)

Kristel Kegler

Full Text Available Gliogenesis under pathophysiological conditions is of particular clinical relevance since it may provide evidence for regeneration promoting cells recruitable for therapeutic purposes. There is evidence that neurotrophin receptor p75 (p75NTR-expressing cells emerge in the lesioned CNS. However, the phenotype and identity of these cells, and signals triggering their in situ generation under normal conditions and certain pathological situations has remained enigmatic. In the present study, we used a spontaneous, idiopathic and inflammatory CNS condition in dogs with prominent lympho-histiocytic infiltration as a model to study the phenotype of Schwann cells and their relation to Schwann cell remyelination within the CNS. Furthermore, the phenotype of p75NTR-expressing cells within the injured CNS was compared to their counter-part in control sciatic nerve and after peripheral nerve injury. In addition, organotypic slice cultures were used to further elucidate the origin of p75NTR-positive cells. In cerebral and cerebellar white and grey matter lesions as well as in the brain stem, p75NTR-positive cells co-expressed the transcription factor Sox2, but not GAP-43, GFAP, Egr2/Krox20, periaxin and PDGFR-α. Interestingly, and contrary to the findings in control sciatic nerves, p75NTR-expressing cells only co-localized with Sox2 in degenerative neuropathy, thus suggesting that such cells might represent dedifferentiated Schwann cells both in the injured CNS and PNS. Moreover, effective Schwann cell remyelination represented by periaxin- and P0-positive mature myelinating Schwann cells, was strikingly associated with the presence of p75NTR/Sox2-expressing Schwann cells. Intriguingly, the emergence of dedifferentiated Schwann cells was not affected by astrocytes, and a macrophage-dominated inflammatory response provided an adequate environment for Schwann cells plasticity within the injured CNS. Furthermore, axonal damage was reduced in brain stem areas

Loss and gain of cone types in vertebrate ciliary photoreceptor evolution.

Science.gov (United States)

Musser, Jacob M; Arendt, Detlev

2017-11-01

Ciliary photoreceptors are a diverse cell type family that comprises the rods and cones of the retina and other related cell types such as pineal photoreceptors. Ciliary photoreceptor evolution has been dynamic during vertebrate evolution with numerous gains and losses of opsin and phototransduction genes, and changes in their expression. For example, early mammals lost all but two cone opsins, indicating loss of cone receptor types in response to nocturnal lifestyle. Our review focuses on the comparison of specifying transcription factors and cell type-specific transcriptome data in vertebrate retinae to build and test hypotheses on ciliary photoreceptor evolution. Regarding cones, recent data reveal that a combination of factors specific for long-wavelength sensitive opsin (Lws)- cones in non-mammalian vertebrates (Thrb and Rxrg) is found across all differentiating cone photoreceptors in mice. This suggests that mammalian ancestors lost all but one ancestral cone type, the Lws-cone. We test this hypothesis by a correlation analysis of cone transcriptomes in mouse and chick, and find that, indeed, transcriptomes of all mouse cones are most highly correlated to avian Lws-cones. These findings underscore the importance of specifying transcription factors in tracking cell type evolution, and shed new light on the mechanisms of cell type loss and gain in retina evolution. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Feedback-induced glutamate spillover enhances negative feedback from horizontal cells to cones

NARCIS (Netherlands)

Vroman, Rozan; Kamermans, M.

2015-01-01

KEY POINTS: In the retina, horizontal cells feed back negatively to cone photoreceptors. Glutamate released from cones can spill over to neighbouring cones. Here we show that cone glutamate release induced by negative feedback can also spill over to neighbouring cones. This glutamate activates the

Feedback-induced glutamate spillover enhances negative feedback from horizontal cells to cones

NARCIS (Netherlands)

Vroman, Rozan; Kamermans, Maarten

2015-01-01

In the retina, horizontal cells feed back negatively to cone photoreceptors. Glutamate released from cones can spill over to neighbouring cones. Here we show that cone glutamate release induced by negative feedback can also spill over to neighbouring cones. This glutamate activates the glutamate

Cardiac cone-beam CT

International Nuclear Information System (INIS)

Manzke, Robert

2005-01-01

This doctoral thesis addresses imaging of the heart with retrospectively gated helical cone-beam computed tomography (CT). A thorough review of the CT reconstruction literature is presented in combination with a historic overview of cardiac CT imaging and a brief introduction to other cardiac imaging modalities. The thesis includes a comprehensive chapter about the theory of CT reconstruction, familiarizing the reader with the problem of cone-beam reconstruction. The anatomic and dynamic properties of the heart are outlined and techniques to derive the gating information are reviewed. With the extended cardiac reconstruction (ECR) framework, a new approach is presented for the heart-rate-adaptive gated helical cardiac cone-beam CT reconstruction. Reconstruction assessment criteria such as the temporal resolution, the homogeneity in terms of the cardiac phase, and the smoothness at cycle-to-cycle transitions are developed. Several reconstruction optimization approaches are described: An approach for the heart-rate-adaptive optimization of the temporal resolution is presented. Streak artifacts at cycle-to-cycle transitions can be minimized by using an improved cardiac weighting scheme. The optimal quiescent cardiac phase for the reconstruction can be determined automatically with the motion map technique. Results for all optimization procedures applied to ECR are presented and discussed based on patient and phantom data. The ECR algorithm is analyzed for larger detector arrays of future cone-beam systems throughout an extensive simulation study based on a four-dimensional cardiac CT phantom. The results of the scientific work are summarized and an outlook proposing future directions is given. The presented thesis is available for public download at www.cardiac-ct.net

Intraoperative squash smear cytology in CNS lesions: A study of 150 pediatric cases

Directory of Open Access Journals (Sweden)

Arpita Jindal

2017-01-01

Full Text Available Background: Tumors of the central nervous system in the pediatric age group occur relatively frequently during the early years of life. Brain tumors are the most common solid malignancies of childhood and only second to acute childhood leukemia. Squash cytology is an indispensable diagnostic aid to central nervous system (CNS lesions. The definitive diagnosis of brain lesions is confirmed by histological examination. Aim: To study the cytology of CNS lesions in pediatric population and correlate it with histopathology. Materials and Methods: One hundred and fifty cases of CNS lesions in pediatric patients were studied over a period of 2 years. Intraoperative squash smears were prepared, stained with hematoxylin and eosin, and examined. Remaining sample was subjected to histopathological examination. Results: Medulloblastoma (24.0% was the most frequently encountered tumor followed by pilocyctic astrocytoma (21.33% and ependymoma (13.33%. Diagnostic accuracy of squash smear technique was 94.67% when compared with histological diagnosis. Conclusion: Smear cytology is a fairly accurate tool for intraoperative CNS consultations.

Cone calorimeter tests of wood composites

Science.gov (United States)

Robert H. White; Kuma Sumathipala

2013-01-01

The cone calorimeter is widely used for the determination of the heat release rate (HRR) of building products and other materials. As part of an effort to increase the availability of cone calorimeter data on wood products, the U.S. Forest Products Laboratory and the American Wood Council conducted this study on composite wood products in cooperation with the Composite...

Intellectual abilities among survivors of childhood leukaemia as a function of CNS irradiation

International Nuclear Information System (INIS)

Eiser, C.

1978-01-01

Twenty-eight children in remission at least 2 years after completing chemotherapy for acute lymphoblastic leukaemia were assessed on standardised psychological tests. It was found that 7 who never had central nervous system (CNS) irradiation and 9 having prophylactic CNS irradiation at least 6 months after diagnosis tended to perform at average or above levels, while those 10 each having prophylactic CNS irradiation (within 2 months of diagnosis) were generally at lower ability. Within the latter group 3 children showed serious intellectual impairments, while the group as a whole functioned especially poorly on quantitative tasks and those involving speeded performance with abstract material. General language ability was not affected. Practical and theoretical implications are discussed. (author)

Quasilinear analysis of loss-cone driven weakly relativistic electron cyclotron maser instability

International Nuclear Information System (INIS)

Ziebell, L.F.; Yoon, P.H.

1995-01-01

This paper presents a quasilinear analysis of the relativistic electron cyclotron maser instability. Two electron populations are assumed: a low-temperature background component and a more energetic loss-cone population. The dispersion relation is valid for any ratio of the energetic to cold populations, and includes thermal and relativistic effects. The quasilinear analysis is based upon an efficient kinetic moment method, in which various moment equations are derived from the particle kinetic equation. A model time-dependent loss-cone electron distribution function is assumed, which allows one to evaluate the instantaneous linear growth rate as well as the moment kinetic equations. These moment equations along with the wave kinetic equation form a fully self-consistent set of equations which governs the evolution of the particles as well as unstable waves. This set of equations is solved with physical parameters typical of the earth's auroral zone plasma. copyright 1995 American Institute of Physics

Cone penetrometer demonstration standard startup review checklist

International Nuclear Information System (INIS)

KRIEG, S.A.

1998-01-01

Startup readiness for the Cone Penetrometer Demonstration in AX Tank Farm will be verified through the application of a Standard Startup Review Checklist. This is a listing of those items essential to demonstrating readiness to start the Cone Penetrometer Demonstration in AX Tank Farm

Revision total knee arthroplasty with the use of trabecular metal cones

DEFF Research Database (Denmark)

Jensen, Claus L; Petersen, Michael Mygind; Schrøder, Henrik

2012-01-01

"Trabecular Metal Cone" (TM Cone) (Zimmer, Inc, Warsaw, Ind) for reconstruction of bone loss in the proximal tibia during revision total knee arthroplasty is now optional. Forty patients were randomized to receive revision total knee arthroplasty with or without TM Cone (No TM Cone). The Anderson...

Derivation of the gauge link in light cone gauge

International Nuclear Information System (INIS)

Gao Jianhua

2010-01-01

In light cone gauge, a gauge link at light cone infinity is necessary for transverse momentum-dependent parton distribution to restore the gauge invariance in some specific boundary conditions. We derive such transverse gauge link in a more regular and general method. We find the gauge link at light cone infinity naturally arises from the contribution of the pinched poles: one is from the quark propagator and the other is hidden in the gauge vector field in light cone gauge. Actually, in the amplitude level, we have obtained a more general gauge link over the hypersurface at light cone infinity which is beyond the transverse direction. The difference of such gauge link between semi-inclusive deep inelastic scattering and Drell-Yan processes can also be obtained directly and clearly in our derivation.

Venomics-Accelerated Cone Snail Venom Peptide Discovery

Science.gov (United States)

Himaya, S. W. A.

2018-01-01

Cone snail venoms are considered a treasure trove of bioactive peptides. Despite over 800 species of cone snails being known, each producing over 1000 venom peptides, only about 150 unique venom peptides are structurally and functionally characterized. To overcome the limitations of the traditional low-throughput bio-discovery approaches, multi-omics systems approaches have been introduced to accelerate venom peptide discovery and characterisation. This “venomic” approach is starting to unravel the full complexity of cone snail venoms and to provide new insights into their biology and evolution. The main challenge for venomics is the effective integration of transcriptomics, proteomics, and pharmacological data and the efficient analysis of big datasets. Novel database search tools and visualisation techniques are now being introduced that facilitate data exploration, with ongoing advances in related omics fields being expected to further enhance venomics studies. Despite these challenges and future opportunities, cone snail venomics has already exponentially expanded the number of novel venom peptide sequences identified from the species investigated, although most novel conotoxins remain to be pharmacologically characterised. Therefore, efficient high-throughput peptide production systems and/or banks of miniaturized discovery assays are required to overcome this bottleneck and thus enhance cone snail venom bioprospecting and accelerate the identification of novel drug leads. PMID:29522462

Venomics-Accelerated Cone Snail Venom Peptide Discovery

Directory of Open Access Journals (Sweden)

S. W. A. Himaya

2018-03-01

Full Text Available Cone snail venoms are considered a treasure trove of bioactive peptides. Despite over 800 species of cone snails being known, each producing over 1000 venom peptides, only about 150 unique venom peptides are structurally and functionally characterized. To overcome the limitations of the traditional low-throughput bio-discovery approaches, multi-omics systems approaches have been introduced to accelerate venom peptide discovery and characterisation. This “venomic” approach is starting to unravel the full complexity of cone snail venoms and to provide new insights into their biology and evolution. The main challenge for venomics is the effective integration of transcriptomics, proteomics, and pharmacological data and the efficient analysis of big datasets. Novel database search tools and visualisation techniques are now being introduced that facilitate data exploration, with ongoing advances in related omics fields being expected to further enhance venomics studies. Despite these challenges and future opportunities, cone snail venomics has already exponentially expanded the number of novel venom peptide sequences identified from the species investigated, although most novel conotoxins remain to be pharmacologically characterised. Therefore, efficient high-throughput peptide production systems and/or banks of miniaturized discovery assays are required to overcome this bottleneck and thus enhance cone snail venom bioprospecting and accelerate the identification of novel drug leads.

P-glycoprotein trafficking as a therapeutic target to optimize CNS drug delivery.

Science.gov (United States)

Davis, Thomas P; Sanchez-Covarubias, Lucy; Tome, Margaret E

2014-01-01

The primary function of the blood-brain barrier (BBB)/neurovascular unit is to protect the central nervous system (CNS) from potentially harmful xenobiotic substances and maintain CNS homeostasis. Restricted access to the CNS is maintained via a combination of tight junction proteins as well as a variety of efflux and influx transporters that limits the transcellular and paracellular movement of solutes. Of the transporters identified at the BBB, P-glycoprotein (P-gp) has emerged as the transporter that is the greatest obstacle to effective CNS drug delivery. In this chapter, we provide data to support intracellular protein trafficking of P-gp within cerebral capillary microvessels as a potential target for improved drug delivery. We show that pain-induced changes in P-gp trafficking are associated with changes in P-gp's association with caveolin-1, a key scaffolding/trafficking protein that colocalizes with P-gp at the luminal membrane of brain microvessels. Changes in colocalization with the phosphorylated and nonphosphorylated forms of caveolin-1, by pain, are accompanied by dynamic changes in the distribution, relocalization, and activation of P-gp "pools" between microvascular endothelial cell subcellular compartments. Since redox-sensitive processes may be involved in signaling disassembly of higher-order structures of P-gp, we feel that manipulating redox signaling, via specific protein targeting at the BBB, may protect disulfide bond integrity of P-gp reservoirs and control trafficking to the membrane surface, providing improved CNS drug delivery. The advantage of therapeutic drug "relocalization" of a protein is that the physiological impact can be modified, temporarily or long term, despite pathology-induced changes in gene transcription. © 2014 Elsevier Inc. All rights reserved.

Avian cone photoreceptors tile the retina as five independent, self-organizing mosaics.

Directory of Open Access Journals (Sweden)

Yoseph A Kram

2010-02-01

Full Text Available The avian retina possesses one of the most sophisticated cone photoreceptor systems among vertebrates. Birds have five types of cones including four single cones, which support tetrachromatic color vision and a double cone, which is thought to mediate achromatic motion perception. Despite this richness, very little is known about the spatial organization of avian cones and its adaptive significance. Here we show that the five cone types of the chicken independently tile the retina as highly ordered mosaics with a characteristic spacing between cones of the same type. Measures of topological order indicate that double cones are more highly ordered than single cones, possibly reflecting their posited role in motion detection. Although cones show spacing interactions that are cell type-specific, all cone types use the same density-dependent yardstick to measure intercone distance. We propose a simple developmental model that can account for these observations. We also show that a single parameter, the global regularity index, defines the regularity of all five cone mosaics. Lastly, we demonstrate similar cone distributions in three additional avian species, suggesting that these patterning principles are universal among birds. Since regular photoreceptor spacing is critical for uniform sampling of visual space, the cone mosaics of the avian retina represent an elegant example of the emergence of adaptive global patterning secondary to simple local interactions between individual photoreceptors. Our results indicate that the evolutionary pressures that gave rise to the avian retina's various adaptations for enhanced color discrimination also acted to fine-tune its spatial sampling of color and luminance.

Glypicans and FGFs in CNS Development and Function

NARCIS (Netherlands)

Galli, Antonella

2003-01-01

One of the most important events during central nervous system (CNS) development is the communication between cells. Cell-to-cell signaling implicates the interaction between a signaling molecules (or ligands) and their receptors. Ligand-receptor interaction is a tightly regulated process and is

Single Cell Electroporation Method for Mammalian CNS Neurons in Organotypic Slice Cultures

Science.gov (United States)

Uesaka, Naofumi; Hayano, Yasufumi; Yamada, Akito; Yamamoto, Nobuhiko

Axon tracing is an essential technique to study the projection pattern of neurons in the CNS. Horse radish peroxidase and lectins have contributed to revealing many neural connection patterns in the CNS (Itaya and van Hoesen, 1982; Fabian and Coulter, 1985; Yoshihara, 2002). Moreover, a tracing method with fluorescent dye has enabled the observation of growing axons in living conditions, and demon strated a lot of developmental aspects in axon growth and guidance (Harris et al., 1987; O'Rourke and Fraser, 1990; Kaethner and Stuermer, 1992; Halloran and Kalil, 1994; Yamamoto et al., 1997). More recently, genetically encoded fluores cent proteins can be used as a powerful tool to observe various biological events. Several gene transfer techniques such as microinjection, biolistic gene gun, viral infection, lipofection and transgenic technology have been developed (Feng et al., 2000; Ehrengruber et al., 2001; O'Brien et al., 2001; Ma et al., 2002; Sahly et al., 2003). In particular, the electroporation technique was proved as a valuable tool, since it can be applied to a wide range of tissues and cell types with little toxicity and can be performed with relative technical easiness. Most methods, including a stand ard electroporation technique, are suitable for gene transfer to a large number of cells. However, this is not ideal for axonal tracing, because observation of individ ual axons is occasionally required. To overcome this problem, we have developed an electroporation method using glass micropipettes containing plasmid solutions and small current injection. Here we introduce the method in detail and exemplified results with some example applications and discuss its usefulness.

Studies on the flammability of polypropylene/ammonium polyphosphate and montmorillonite by using the cone calorimeter test

Directory of Open Access Journals (Sweden)

Hanna A.A.

2018-03-01

Full Text Available Fire performance of polypropylene (PP containing different percentages of ammonium polyphosphate (APP with montmorillonite (Mt or treated montmorillonite (MtT was carried out by using the cone calorimeter test (CCT. Different samples from ammonium polyphosphate and montmorillonite were mixed with 90% polypropylene. The characterization of the prepared samples indicates that there is incorporation between the components of the samples. Heat release rate (HRR, peak heat release rate (PHRR, average heat release rate (Av-HRR, and time to ignition (TTI of the samples were obtained from the cone calorimeter test. Also, the fire performance index (FPI and the fire growth rate (FIGRA were calculated. The interpretation of the curves and the parameters results from the cone calorimeter test which indicates that the addition of montmorillonite to APP increases its action as a flame retardant for PP. Moreover, the samples contain acid treatment montmorillonite showed an increase in the efficiency of ammonium polyphosphate when used. This result may be due to an increase in the SiO2 content by acid treatment.

Ring resonator optical modes in InGaN/GaN structures grown on micro-cone-patterned sapphire substrates

Science.gov (United States)

Kazanov, D. R.; Pozina, G.; Jmerik, V. N.; Shubina, T. V.

2018-03-01

Molecular beam epitaxy (MBE) of III-nitride compounds on specially prepared cone-shaped patterned substrates is being actively developed nowadays, especially for nanophotonic applications. This type of substrates enables the successful growth of hexagonal nanorods (NRs). The insertion of an active quantum-sized region of InGaN inside a GaN NR allows us to enhance the rate of optical transitions by coupling them with resonant optical modes in the NR. However, we have observed the enhancement of emission not only from the NR but also around the circumference region of the cone-shaped base. We have studied this specific feature and demonstrated its impact on the output signal.

Recombinant human tripeptidyl peptidase-1 infusion to the monkey CNS: Safety, pharmacokinetics, and distribution

Energy Technology Data Exchange (ETDEWEB)

Vuillemenot, Brian R., E-mail: bvuillemenot@bmrn.com [BioMarin Pharmaceutical Inc., Novato, CA (United States); Kennedy, Derek [BioMarin Pharmaceutical Inc., Novato, CA (United States); Reed, Randall P.; Boyd, Robert B. [Northern Biomedical Research, Inc., Muskegon, MI (United States); Butt, Mark T. [Tox Path Specialists, LLC, Hagerstown, MD (United States); Musson, Donald G.; Keve, Steve; Cahayag, Rhea; Tsuruda, Laurie S.; O' Neill, Charles A. [BioMarin Pharmaceutical Inc., Novato, CA (United States)

2014-05-15

CLN2 disease is caused by deficiency in tripeptidyl peptidase-1 (TPP1), leading to neurodegeneration and death. The safety, pharmacokinetics (PK), and CNS distribution of recombinant human TPP1 (rhTPP1) were characterized following a single intracerebroventricular (ICV) or intrathecal-lumbar (IT-L) infusion to cynomolgus monkeys. Animals received 0, 5, 14, or 20 mg rhTPP1, ICV, or 14 mg IT-L, in artificial cerebrospinal fluid (aCSF) vehicle. Plasma and CSF were collected for PK analysis. Necropsies occurred at 3, 7, and 14 days post-infusion. CNS tissues were sampled for rhTPP1 distribution. TPP1 infusion was well tolerated and without effect on clinical observations or ECG. A mild increase in CSF white blood cells (WBCs) was detected transiently after ICV infusion. Isolated histological changes related to catheter placement and infusion were observed in ICV treated animals, including vehicle controls. The CSF and plasma exposure profiles were equivalent between animals that received an ICV or IT-L infusion. TPP1 levels peaked at the end of infusion, at which point the enzyme was present in plasma at 0.3% to 0.5% of CSF levels. TPP1 was detected in brain tissues with half-lives of 3–14 days. CNS distribution between ICV and IT-L administration was similar, although ICV resulted in distribution to deep brain structures including the thalamus, midbrain, and striatum. Direct CNS infusion of rhTPP1 was well tolerated with no drug related safety findings. The favorable nonclinical profile of ICV rhTPP1 supports the treatment of CLN2 by direct administration to the CNS. - Highlights: • TPP1 enzyme replacement therapy to the CNS is in development for CLN2 disease. • Toxicology, pharmacokinetics, and CNS distribution were assessed in monkeys. • TPP1 infusion directly to the brain did not result in any safety concerns. • A positive pharmacokinetic and distribution profile resulted from TPP1 infusion. • This study demonstrates the feasibility of ICV administered

Recombinant human tripeptidyl peptidase-1 infusion to the monkey CNS: Safety, pharmacokinetics, and distribution

International Nuclear Information System (INIS)

Vuillemenot, Brian R.; Kennedy, Derek; Reed, Randall P.; Boyd, Robert B.; Butt, Mark T.; Musson, Donald G.; Keve, Steve; Cahayag, Rhea; Tsuruda, Laurie S.; O'Neill, Charles A.

2014-01-01

CLN2 disease is caused by deficiency in tripeptidyl peptidase-1 (TPP1), leading to neurodegeneration and death. The safety, pharmacokinetics (PK), and CNS distribution of recombinant human TPP1 (rhTPP1) were characterized following a single intracerebroventricular (ICV) or intrathecal-lumbar (IT-L) infusion to cynomolgus monkeys. Animals received 0, 5, 14, or 20 mg rhTPP1, ICV, or 14 mg IT-L, in artificial cerebrospinal fluid (aCSF) vehicle. Plasma and CSF were collected for PK analysis. Necropsies occurred at 3, 7, and 14 days post-infusion. CNS tissues were sampled for rhTPP1 distribution. TPP1 infusion was well tolerated and without effect on clinical observations or ECG. A mild increase in CSF white blood cells (WBCs) was detected transiently after ICV infusion. Isolated histological changes related to catheter placement and infusion were observed in ICV treated animals, including vehicle controls. The CSF and plasma exposure profiles were equivalent between animals that received an ICV or IT-L infusion. TPP1 levels peaked at the end of infusion, at which point the enzyme was present in plasma at 0.3% to 0.5% of CSF levels. TPP1 was detected in brain tissues with half-lives of 3–14 days. CNS distribution between ICV and IT-L administration was similar, although ICV resulted in distribution to deep brain structures including the thalamus, midbrain, and striatum. Direct CNS infusion of rhTPP1 was well tolerated with no drug related safety findings. The favorable nonclinical profile of ICV rhTPP1 supports the treatment of CLN2 by direct administration to the CNS. - Highlights: • TPP1 enzyme replacement therapy to the CNS is in development for CLN2 disease. • Toxicology, pharmacokinetics, and CNS distribution were assessed in monkeys. • TPP1 infusion directly to the brain did not result in any safety concerns. • A positive pharmacokinetic and distribution profile resulted from TPP1 infusion. • This study demonstrates the feasibility of ICV administered

Design of a cone target for fast ignition

Directory of Open Access Journals (Sweden)

Sunahara Atsushi

2013-11-01

Full Text Available We propose a new type of target for the fast ignition of inertial confinement fusion. Pre-formed plasma inside a cone target can significantly reduce the energy coupling efficiency from the ultra-high intense short-pulse laser to the imploded core plasma. Also, in order to protect the tip of the cone and reduce generation of pre-formed plasma, we propose pointed shaped cone target. In our estimation, the shock traveling time can be delayed 20–30 ps by lower-Z material with larger areal density compared to the conventional gold flat tip. Also, the jet flow can sweep the blow-off plasma from the tip of the cone, and the implosion performance is not drastically affected by the existence of pointed tip. In addition, the self-generated magnetic field is generated along the boundary of cone tip and surrounding CD or DT plasma. This magnetic field can confine fast electrons and focus to the implosion core plasma. Resultant heating efficiency is improved by 30% compared to that with conventional gold flat tip.

Noise masking of S-cone increments and decrements.

Science.gov (United States)

Wang, Quanhong; Richters, David P; Eskew, Rhea T

2014-11-12

S-cone increment and decrement detection thresholds were measured in the presence of bipolar, dynamic noise masks. Noise chromaticities were the L-, M-, and S-cone directions, as well as L-M, L+M, and achromatic (L+M+S) directions. Noise contrast power was varied to measure threshold Energy versus Noise (EvN) functions. S+ and S- thresholds were similarly, and weakly, raised by achromatic noise. However, S+ thresholds were much more elevated by S, L+M, L-M, L- and M-cone noises than were S- thresholds, even though the noises consisted of two symmetric chromatic polarities of equal contrast power. A linear cone combination model accounts for the overall pattern of masking of a single test polarity well. L and M cones have opposite signs in their effects upon raising S+ and S- thresholds. The results strongly indicate that the psychophysical mechanisms responsible for S+ and S- detection, presumably based on S-ON and S-OFF pathways, are distinct, unipolar mechanisms, and that they have different spatiotemporal sampling characteristics, or contrast gains, or both. © 2014 ARVO.

Identifying Dirac cones in carbon allotropes with square symmetry

Energy Technology Data Exchange (ETDEWEB)

Wang, Jinying [College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Huang, Huaqing; Duan, Wenhui [Department of Physics, Tsinghua University, Beijing 100084 (China); Liu, Zhirong, E-mail: LiuZhiRong@pku.edu.cn [College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); State Key Laboratory for Structural Chemistry of Unstable and Stable Species and Beijing National Laboratory for Molecular Sciences (BNLMS), Peking University, Beijing 100871 (China)

2013-11-14

A theoretical study is conducted to search for Dirac cones in two-dimensional carbon allotropes with square symmetry. By enumerating the carbon atoms in a unit cell up to 12, an allotrope with octatomic rings is recognized to possess Dirac cones under a simple tight-binding approach. The obtained Dirac cones are accompanied by flat bands at the Fermi level, and the resulting massless Dirac-Weyl fermions are chiral particles with a pseudospin of S = 1, rather than the conventional S = 1/2 of graphene. The spin-1 Dirac cones are also predicted to exist in hexagonal graphene antidot lattices.

Conical Refraction: new observations and a dual cone model.

Science.gov (United States)

Sokolovskii, G S; Carnegie, D J; Kalkandjiev, T K; Rafailov, E U

2013-05-06

We propose a paraxial dual-cone model of conical refraction involving the interference of two cones of light behind the exit face of the crystal. The supporting experiment is based on beam selecting elements breaking down the conically refracted beam into two separate hollow cones which are symmetrical with one another. The shape of these cones of light is a product of a 'competition' between the divergence caused by the conical refraction and the convergence due to the focusing by the lens. The developed mathematical description of the conical refraction demonstrates an excellent agreement with experiment.

Conceptual Design of Deployment Structure of Morphing Nose Cone

Directory of Open Access Journals (Sweden)

Junlan Li

2013-01-01

Full Text Available For a reusable space vehicle or a missile, the shape of the nose cone has a significant effect on the drag of the vehicle. In this paper, the concept of morphing nose cone is proposed to reduce the drag when the reentry vehicle flies back into the atmosphere. The conceptual design of the structure of morphing nose cone is conducted. Mechanical design and optimization approach are developed by employing genetic algorithm to find the optimal geometric parameters of the morphing structure. An example is analyzed by using the proposed method. The results show that optimal solution supplies the minimum position error. The concept of morphing nose cone will provide a novel way for the drag reduction of reentry vehicle. The proposed method could be practically used for the design and optimization of the deployable structure of morphing nose cone.

Tailored central nervous system-directed treatment strategy for isolated CNS recurrence of adult acute myeloid leukemia.

Science.gov (United States)

Zheng, Changcheng; Liu, Xin; Zhu, Weibo; Cai, Xiaoyan; Wu, Jingsheng; Sun, Zimin

2014-06-01

The aim of this report was to investigate the tailored treatment strategies for isolated central nervous system (CNS) recurrence in adult patients with acute myeloid leukemia (AML). Isolated CNS recurrence was documented in 34 patients: there were 18, 6, and 10 patients with meningeal involvement type (type A), cranial nerve palsy type (type B), and myeloid sarcoma type (type C), respectively. For patients with type A, intrathecal chemotherapy was the predominant strategy. For type B, systemic HD-Ara-C with four cycles was the main treatment. For type C, cranial irradiation or craniospinal irradiation was adopted and two cycles of HD-Ara-C were given after the irradiation. The 5-year cumulative incidence of CNS recurrence was 12.8%. There was a significantly higher WBC count (32.6∼60.8 × 10(9)/l) in patients at first diagnosis who developed CNS recurrence (all of the three types) compared with patients with no CNS recurrence (10.1 × 10(9)/l) (P = 0.005). We found that a significantly more patients with AML-M5 and 11q23 abnormalities developed CNS recurrence in type A (P adult AML, but further studies are needed to improve the long-term survival.

Full utilization of semi-Dirac cones in photonics

Science.gov (United States)

Yasa, Utku G.; Turduev, Mirbek; Giden, Ibrahim H.; Kurt, Hamza

2018-05-01

In this study, realization and applications of anisotropic zero-refractive-index materials are proposed by exposing the unit cells of photonic crystals that exhibit Dirac-like cone dispersion to rotational symmetry reduction. Accidental degeneracy of two Bloch modes in the Brillouin zone center of two-dimensional C2-symmetric photonic crystals gives rise to the semi-Dirac cone dispersion. The proposed C2-symmetric photonic crystals behave as epsilon-and-mu-near-zero materials (ɛeff≈ 0 , μeff≈ 0 ) along one propagation direction, but behave as epsilon-near-zero material (ɛeff≈ 0 , μeff≠ 0 ) for the perpendicular direction at semi-Dirac frequency. By extracting the effective medium parameters of the proposed C4- and C2-symmetric periodic media that exhibit Dirac-like and semi-Dirac cone dispersions, intrinsic differences between isotropic and anisotropic materials are investigated. Furthermore, advantages of utilizing semi-Dirac cone materials instead of Dirac-like cone materials in photonic applications are demonstrated in both frequency and time domains. By using anisotropic transmission behavior of the semi-Dirac materials, photonic application concepts such as beam deflectors, beam splitters, and light focusing are proposed. Furthermore, to the best of our knowledge, semi-Dirac cone dispersion is also experimentally demonstrated for the first time by including negative, zero, and positive refraction states of the given material.

Cadmium Removal from Aqueous Solutions by Ground Pine Cone

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H Izanloo, S Nasseri

2005-01-01

Full Text Available A study on the removal of cadmium ions from aqueous solutions by pine cone was conducted in batch conditions. Kinetic data and equilibrium removal isotherms were obtained. The influence of different experimental parameters such as contact time, initial concentration of cadmium, pine cone mass and particle size, and temperature on the kinetics of cadmium removal was studied. Results showed that the main parameters that played an important role in removal phenomenon were initial cadmium concentration, particle size and pine cone mass. The necessary time to reach equilibrium was between 4 and 7 hours based on the initial concentration of cadmium. The capacity of cadmium adsorption at equilibrium increased with the decrease of pine cone particle size. The capacity of cadmium adsorption at equilibrium by pine cone increased with the quantity of pine cone introduced (1–4 g/L. Temperature in the range of 20-30°C showed a restricted effect on the removal kinetics (13.56 mg/g at 20°C and a low capacity of adsorption about 11.48 mg/g at 30°C. The process followed pseudo second-order kinetics. The cadmium uptake of pine cone was quantitatively evaluated using adsorption isotherms. Results indicated that the Langmuir model gave a better fit to the experimental data in comparison with the Freundlich equation.

Treatment options for Primary CNS Lymphoma.

Science.gov (United States)

Laghari, Altaf Ali; Ahmed, Syed Ijlal; Jabbar, Adnan; Shamim, Muhammad Shahzad

2018-03-01

Primary CNS lymphoma (PCNSL) is a rare and aggressive brain tumour that is uniformly fatal. The rarity of the disease and the poor response to treatment makes it difficult to reach a consensus with regards to treatment options. In this review, the authors have discussed different treatment modalities used in the management of PCNSL including chemotherapy, surgery and radiation, as well as the results of recent clinical trials on treatment options for PCNSL.

Ketamine displaces the novel NMDA receptor SPET probe [{sup 123}I]CNS-1261 in humans in vivo

Energy Technology Data Exchange (ETDEWEB)

Stone, James M. [Institute of Psychiatry, King' s College London, De Crespigny Park London, SE5 8AF (United Kingdom)]. E-mail: j.stone@iop.kcl.ac.uk; Erlandsson, Kjell [Institute of Nuclear Medicine, University College London, London, W1N 8AA (United Kingdom); Arstad, Erik [Institute of Psychiatry, King' s College London, De Crespigny Park London, SE5 8AF (United Kingdom); Bressan, Rodrigo A. [Institute of Psychiatry, King' s College London, De Crespigny Park London, SE5 8AF (United Kingdom); Squassante, Lisa [GlaxoSmithKline (GSK), Verona 37135 (Italy); Teneggi, Vincenza [GlaxoSmithKline (GSK), Verona 37135 (Italy); Ell, Peter J. [Institute of Nuclear Medicine, University College London, London, W1N 8AA (United Kingdom); Pilowsky, Lyn S. [Institute of Psychiatry, King' s College London, De Crespigny Park London, SE5 8AF (United Kingdom); Institute of Nuclear Medicine, University College London, London, W1N 8AA (United Kingdom)

2006-02-15

[{sup 123}I]CNS-1261 [N-(1-naphthyl)-N'-(3-iodophenyl)-N-methylguanidine] is a high-affinity SPET ligand with selectivity for the intrachannel PCP/ketamine/MK-801 site of the N-methyl-D-aspartate (NMDA) receptor. This study evaluated the effects of ketamine (a specific competitor for the intrachannel PCP/ketamine/MK-801 site) on [{sup 123}I]CNS-1261 binding to NMDA receptors in vivo. Ten healthy volunteers underwent 2 bolus-plus-infusion [{sup 123}I]CNS-1261 scans, one during placebo and the other during a ketamine challenge. Ketamine administration led to a significant decrease in [{sup 123}I]CNS-1261 V {sub T} in most of the brain regions examined (P<.05). [{sup 123}I]CNS-1261 appears to be a specific ligand in vivo for the intrachannel PCP/ketamine/MK-801 NMDA binding site.

Nuclear innovation through collaboration. 35th Annual CNS conference and 39th CNS/CNA student conference

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-07-01

The Canadian Nuclear Society (CNS) held its 35th Annual Conference in Saint John, New Brunswick, Canada on May 31 to June 3, 2015, combined with the 39th Annual CNS/CNA Student Conference. With the theme of the conference, 'Nuclear Innovation through Collaboration', more than 425 delegates, exhibitors and students were in attendance. The conference commenced with two strong plenary sessions on Utility Collaborations to Improve Lifetime Performance; and, Performance Improvement Programs: Goals and Experience. The second day consisted of the panel discussions on International Developments in Used Nuclear Fuel Repository Programs, and two plenary sessions on: Enterprise Risk Management; and, Vendor Role in a Continuously Improving Industry. The third day contained a number of interesting features, including plenary sessions on Waste Management and Decommissioning; Developing Technologies and Resources, and a panel discussion on the Transportation of Used Nuclear Fuel. All three days of the conference also contained parallel sessions with over 100 technical papers presented at the main and student sessions. The technical session titles were: Refurbishment and Life Extension; Thermalhydraulics; Nuclear Materials; WMD - Radiation Monitoring; Safety and Licensing; Communication; Safety and Licensing; Instrumentation and Control; Advanced Reactor Designs; WMD - Deep Geological Repository Packaging; Reactor Physics; Chemistry and Materials; Advanced Fuel Cycles; Waste Management and Decommissioning; and, Medical Physics and Radiation Biology.

JWFront: Wavefronts and Light Cones for Kerr Spacetimes

Science.gov (United States)

Frutos Alfaro, Francisco; Grave, Frank; Müller, Thomas; Adis, Daria

2015-04-01

JWFront visualizes wavefronts and light cones in general relativity. The interactive front-end allows users to enter the initial position values and choose the values for mass and angular momentum per unit mass. The wavefront animations are available in 2D and 3D; the light cones are visualized using the coordinate systems (t, x, y) or (t, z, x). JWFront can be easily modified to simulate wavefronts and light cones for other spacetime by providing the Christoffel symbols in the program.

Tracking blue cone signals in the primate brain.

Science.gov (United States)

Jayakumar, Jaikishan; Dreher, Bogdan; Vidyasagar, Trichur R

2013-05-01

In this paper, we review the path taken by signals originating from the short wavelength sensitive cones (S-cones) in Old World and New World primates. Two types of retinal ganglion cells (RGCs) carrying S-cone signals (blue-On and blue-Off cells) project to the dorsal lateral geniculate nucleus (dLGN) in the thalamus. In all primates, these S-cone signals are relayed through the 'dust-like' (konis in classical Greek) dLGN cells. In New World primates such as common marmoset, these very small cells are known to form distinct and spatially extensive, koniocellular layers. Although in Old World primates, such as macaques, koniocellular layers tend to be very thin, the adjacent parvocellular layers contain distinct koniocellular extensions. It appears that all S-cone signals are relayed through such konio cells, whether they are in the main koniocellular layers or in their colonies within the parvocellular layers of the dLGN. In the primary visual cortex, these signals begin to merge with the signals carried by the other two principal parallel channels, namely the magnocellular and parvocellular channels. This article will also review the possible routes taken by the S-cone signals to reach one of the topographically organised extrastriate visual cortical areas, the middle temporal area (area MT). This area is the major conduit for signals reaching the parietal cortex. Alternative visual inputs to area MT not relayed via the primary visual cortex area (V1) may provide the neurological basis for the phenomenon of 'blindsight' observed in human and non-human primates, who have partial or complete damage to the primary visual cortex. Short wavelength sensitive cone (S-cone) signals to area MT may also play a role in directing visual attention with possible implications for understanding the pathology in dyslexia and some of its treatment options. © 2012 The Authors. Clinical and Experimental Optometry © 2012 Optometrists Association Australia.

Cinder cones of Mount Slamet, Central Java, Indonesia

Directory of Open Access Journals (Sweden)

Igan S. SutawIdjaja

2014-06-01

Full Text Available http://dx.doi.org/10.17014/ijog.vol4no1.20096The Mount Slamet volcanic field in Central Java, Indonesia, contains thirty five cinder cones within an area of 90 sq. km in the east flank of the volcano. The cinder cones occur singly or in small groups, with diameter of the base ranges from 130 - 750 m and the height is around 250 m. Within the volcanic field, the cinder cones are spread over the volcanic area at the distance of 4 to 14 km from the eruption center of the Slamet Volcano. They are concentrated within latitudes 7°11’00” - 7°16’00” S,, and longitudes 109°15’00” - 109°18’00” E. The density of the cinder cones is about 1.5 cones/km2. Most of the cinder cones lie on the Tertiary sedimentary rocks along the NW-trending fault system and on radial fractures. The structural pattern may be related to the radial faults in this region. The cone surfaces are commonly blanketed by Slamet air-falls and lava flows. The deposits consist of poorly bedded, very coarse-grained, occasionally overlain by oxidized scoria, and large-sized of ballistic bombs and blocks. There are various kind of volcanic bombs originating from scoriae ballistic rock fragments. The other kind of volcanic bombs are breadcrust bomb, almond seed or contorted shape. All of the cinder cones have undergone degradation, which can be observed from the characters of gully density and surface morphology. By using Porter parameters, Hco is equal to 0.25 Wco, whilst Wcr is equal to 0.40 Wco. The Hco/Wco ratio is higher than Hco = 0.2 Wco reference line. A radiometric dating using K-Ar method carried out on a scoria bomb yields the age of 0.042 + 0.020 Ma.  

Jordan's algebra of a facially homogeneous autopolar cone

International Nuclear Information System (INIS)

Bellissard, Jean; Iochum, Bruno

1979-01-01

It is shown that a Jordan-Banach algebra with predual may be canonically associated with a facially homogeneous autopolar cone. This construction generalizes the case where a trace vector exists in the cone [fr

Nonlinear interactions of focused resonance cone fields with plasmas

International Nuclear Information System (INIS)

Stenzel, R.L.; Gekelman, W.

1977-01-01

A simple yet novel rf exciter structure has been developed for generating remotely intense rf fields in a magnetoplasma. It is a circular line source of radius R in a plane perpendicularB 0 driven with an rf signal at ω 0 E/sub rf/ 2 /nkT/sub e/>0.2, a strong density depression in the focal region (deltan/n>40%) is observed. The density perturbation modifies the cone angle and field distribution. This nonlinear interaction leads to a rapid growth of ion acoustic wave turbulence and a corresponding random rf field distribution in a broadened focal region. The development of the interaction is mapped in space and time

Modified superstring in light cone gauge

International Nuclear Information System (INIS)

Kamimura, Kiyoshi; Tatewaki, Machiko.

1988-01-01

We analyze the covariant superstring theory proposed by Siegel in light cone gauge. The physical states are the direct product of those of Green-Schwarz Superstring and the additional internal space spanned by light cone spinors. At clasical level, there is no difference among observables in Siegel's modified Superstring theory (SMST) and Green-Schwarz's one (GSST). However SMST can not be quantized with additional constraints as the physical state conditions. (author)

Quantifying mechanical force in axonal growth and guidance

Directory of Open Access Journals (Sweden)

Ahmad Ibrahim Mahmoud Athamneh

2015-09-01

Full Text Available Mechanical force plays a fundamental role in neuronal development, physiology, and regeneration. In particular, research has shown that force is involved in growth cone-mediated axonal growth and guidance as well as stretch-induced elongation when an organism increases in size after forming initial synaptic connections. However, much of the details about the exact role of force in these fundamental processes remain unknown. In this review, we highlight (1 standing questions concerning the role of mechanical force in axonal growth and guidance and (2 different experimental techniques used to quantify forces in axons and growth cones. We believe that satisfying answers to these questions will require quantitative information about the relationship between elongation, forces, cytoskeletal dynamics, axonal transport, signaling, substrate adhesion, and stiffness contributing to directional growth advance. Furthermore, we address why a wide range of force values have been reported in the literature, and what these values mean in the context of neuronal mechanics. We hope that this review will provide a guide for those interested in studying the role of force in development and regeneration of neuronal networks.

Comparison of the WSA-ENLIL model with three CME cone types

Science.gov (United States)

Jang, Soojeong; Moon, Y.; Na, H.

2013-07-01

We have made a comparison of the CME-associated shock propagation based on the WSA-ENLIL model with three cone types using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters as well as their associated interplanetary (IP) shocks. For this study we consider three different cone types (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine 3-D CME parameters (radial velocity, angular width and source location), which are the input values of the WSA-ENLIL model. The mean absolute error (MAE) of the arrival times for the asymmetric cone model is 10.6 hours, which is about 1 hour smaller than those of the other models. Their ensemble average of MAE is 9.5 hours. However, this value is still larger than that (8.7 hours) of the empirical model of Kim et al. (2007). We will compare their IP shock velocities and densities with those from ACE in-situ measurements and discuss them in terms of the prediction of geomagnetic storms.Abstract (2,250 Maximum Characters): We have made a comparison of the CME-associated shock propagation based on the WSA-ENLIL model with three cone types using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters as well as their associated interplanetary (IP) shocks. For this study we consider three different cone types (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine 3-D CME parameters (radial velocity, angular width and source location), which are the input values of the WSA-ENLIL model. The mean absolute error (MAE) of the arrival times for the asymmetric cone model is 10.6 hours, which is about 1 hour smaller than those of the other models. Their ensemble average of MAE is 9.5 hours. However, this value is still larger than that (8.7 hours) of the empirical model of Kim et al. (2007). We will compare their IP shock velocities and densities with those from ACE in-situ measurements and discuss them in terms of the

The light-cone Fock state expansion and hadron physics phenomenology

International Nuclear Information System (INIS)

Brodsky, S.J.

1997-06-01

The light-cone Fock expansion is defined in the following way: one first constructs the light-cone time evolution operator and the invariant mass operator in light-cone gauge from the QCD Lagrangian. The total longitudinal momentum and transverse momenta are conserved, i.e. are independent of the interactions. The matrix elements of the invariant mass operator on the complete orthonormal basis of the free theory can then be constructed. The matrix elements connect Fock states differing by 0, 1, or 2 quark or gluon quanta, and they include the instantaneous quark and gluon contributions imposed by eliminating dependent degrees of freedom in light-cone gauge. Applications of light-cone methods to QCD phenomenology are briefly described

Neonatal CNS infection and inflammation caused by Ureaplasma species: rare or relevant?

Science.gov (United States)

Glaser, Kirsten; Speer, Christian P

2015-02-01

Colonization with Ureaplasma species has been associated with adverse pregnancy outcome, and perinatal transmission has been implicated in the development of bronchopulmonary dysplasia in preterm neonates. Little is known about Ureaplasma-mediated infection and inflammation of the CNS in neonates. Controversy remains concerning its incidence and implication in the pathogenesis of neonatal brain injury. In vivo and in vitro data are limited. Despite improving care options for extremely immature preterm infants, relevant complications remain. Systematic knowledge of ureaplasmal infection may be of great benefit. This review aims to summarize pathogenic mechanisms, clinical data and diagnostic pitfalls. Studies in preterm and term neonates are critically discussed with regard to their limitations. Clinical questions concerning therapy or prophylaxis are posed. We conclude that ureaplasmas may be true pathogens, especially in preterm neonates, and may cause CNS inflammation in a complex interplay of host susceptibility, serovar pathogenicity and gestational age-dependent CNS vulnerability.

Rapid Recovery of Visual Function Associated with Blue Cone Ablation in Zebrafish

Science.gov (United States)

Hagerman, Gordon F.; Noel, Nicole C. L.; Cao, Sylvia Y.; DuVal, Michèle G.; Oel, A. Phillip; Allison, W. Ted

2016-01-01

Hurdles in the treatment of retinal degeneration include managing the functional rewiring of surviving photoreceptors and integration of any newly added cells into the remaining second-order retinal neurons. Zebrafish are the premier genetic model for such questions, and we present two new transgenic lines allowing us to contrast vision loss and recovery following conditional ablation of specific cone types: UV or blue cones. The ablation of each cone type proved to be thorough (killing 80% of cells in each intended cone class), specific, and cell-autonomous. We assessed the loss and recovery of vision in larvae via the optomotor behavioural response (OMR). This visually mediated behaviour decreased to about 5% or 20% of control levels following ablation of UV or blue cones, respectively (Pvision recovery following UV cone ablation was robust, as measured by both assays, returning to control levels within four days. In contrast, robust functional recovery following blue cone ablation was unexpectedly rapid, returning to normal levels within 24 hours after ablation. Ablation of cones led to increased proliferation in the retina, though the rapid recovery of vision following blue cone ablation was demonstrated to not be mediated by blue cone regeneration. Thus rapid visual recovery occurs following ablation of some, but not all, cone subtypes, suggesting an opportunity to contrast and dissect the sources and mechanisms of outer retinal recovery during cone photoreceptor death and regeneration. PMID:27893779

A remote control neutron cone scanner and measurement of the d(T,n) α neutron cone

International Nuclear Information System (INIS)

Suwanakachorn, D.; Vilaithong, T.; Vilaithong, C.; Boonyawan, D.; Chimooy, T.; Sornphorm, P.; Hoyce, G.; Pairsuwan, W.; Singkarat, S.

1988-01-01

We have measured the neutron cone associated with alpha particles from the d(T,n)α reaction by using a remote-control cone scanner. This scanner has two principal parts. The first part is the neutron detector scanner which can move the detector in the horizontal and vertical axis using to stepping-motors. The neutron detector can be moved in 0.5 cm increments over the whole rage of 30 cm. The second part is the remote-control electronic circuit using digital ICs. The rotation of stepping-motors is controlled by pulse signals from this circuit and the position of the detector is known by counting the number of pulses. The position of the neutron detector is indicated directly on a 3 digit display at the control panel. The method of measuring the neutron cone by the Time-of-Flight technique is also described

History of imaging in orthodontics from Broadbent to cone-beam computed tomography.

Science.gov (United States)

Hans, Mark G; Palomo, J Martin; Valiathan, Manish

2015-12-01

The history of imaging and orthodontics is a story of technology informing biology. Advances in imaging changed our thinking as our understanding of craniofacial growth and the impact of orthodontic treatment deepened. This article traces the history of imaging in orthodontics from the invention of the cephalometer by B. Holly Broadbent in 1930 to the introduction of low-cost, low-radiation-dose cone-beam computed tomography imaging in 2015. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Alcohol intake alters immune responses and promotes CNS viral persistence in mice.

Science.gov (United States)

Loftis, Jennifer M; Taylor, Jonathan; Raué, Hans-Peter; Slifka, Mark K; Huang, Elaine

2016-10-01

Chronic hepatitis C virus (HCV) infection leads to progressive liver disease and is associated with a variety of extrahepatic effects, including central nervous system (CNS) damage and neuropsychiatric impairments. Alcohol abuse can exacerbate these adverse effects on brain and behavior, but the molecular mechanisms are not well understood. This study investigated the role of alcohol in regulating viral persistence and CNS immunopathology in mice infected with lymphocytic choriomeningitis virus (LCMV), a model for HCV infections in humans. Female and male BALB/c mice (n=94) were exposed to alcohol (ethanol; EtOH) and water (or water only) using a two-bottle choice paradigm, followed one week later by infection with either LCMV clone 13 (causes chronic infection similar to chronic HCV), LCMV Armstrong (causes acute infection), or vehicle. Mice were monitored for 60days post-infection and continued to receive 24-h access to EtOH and water. Animals infected with LCMV clone 13 drank more EtOH, as compared to those with an acute or no viral infection. Six weeks after infection with LCMV clone 13, mice with EtOH exposure evidenced higher serum viral titers, as compared to mice without EtOH exposure. EtOH intake was also associated with reductions in virus-specific CD8(+) T cell frequencies (particularly CD11a(hi) subsets) and evidence of persistent CNS viremia in chronically infected mice. These findings support the hypothesis that EtOH use and chronic viral infection can result in combined toxic effects accelerating CNS damage and neuropsychiatric dysfunction and suggest that examining the role of EtOH in regulating viral persistence and CNS immunopathology in mice infected with LCMV can lead to a more comprehensive understanding of comorbid alcohol use disorder and chronic viral infection. Published by Elsevier B.V.

Drought effects on reproductive and growth characteristics in seed orchards

International Nuclear Information System (INIS)

Varol, T.; Ozel, H. B.; Bilir, N.

2017-01-01

Global climate change is one of the most important environmental problems, and it is also known that this change will lead to negative effects such as drought and increase in global temperature. This change is also estimated to increase its episodic effects negatively on growth and reproduction of the forest trees. In order to estimate the episodic or continuous effects of the drought, it is necessary to carry out studies based on long-term data. One of these studies are the investigation to be carried out on seed orchards that are one of the most important seed resources in forestry. Within this context, in this study, we determined to the reproductive and growth responses of the clones to the drought that continued in the most drought season (2012) for 2 subsequent years along with 65-year climate data for Red Pine (Pinus brutia Ten.) and Taurus Cedar (Cedrus libani Rich.). The relationships of SPEI values with seed characteristics and cone production were examined by using Spearman Correlation Analysis. According to the results obtained from this study, it was found that the severe drought was effected the reproductive characteristics of both of red pine and cedar. The effect of drought on the number of cone (r=-0.810, P=0.022) in red pine and on the number of 1-year-old cones (r=-0.40, P=0.027) and on cone moisture (r=-0.715, P=0.022) in cedar was quite evident. These results indicate that approximately 65% of the change in number of cone in Red Pine and approximately 51% of the change in moisture content of the cones in cedar can be explained with the drought. From the data, it is clear that the drought is effective on the cone yield and seed characteristics in seed orchards of both of Red Pine and Taurus Cedar species. (author)

Development of a full ice-cream cone model for halo CME structures

Science.gov (United States)

Na, Hyeonock; Moon, Yong-Jae

2015-04-01

The determination of three dimensional parameters (e.g., radial speed, angular width, source location) of Coronal Mass Ejections (CMEs) is very important for space weather forecast. To estimate these parameters, several cone models based on a flat cone or a shallow ice-cream cone with spherical front have been suggested. In this study, we investigate which cone model is proper for halo CME morphology using 33 CMEs which are identified as halo CMEs by one spacecraft (SOHO or STEREO-A or B) and as limb CMEs by the other ones. From geometrical parameters of these CMEs such as their front curvature, we find that near full ice-cream cone CMEs (28 events) are dominant over shallow ice-cream cone CMEs (5 events). So we develop a new full ice-cream cone model by assuming that a full ice-cream cone consists of many flat cones with different heights and angular widths. This model is carried out by the following steps: (1) construct a cone for given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, (4) minimize the difference between the estimated projection points with the observed ones. We apply this model to several halo CMEs and compare the results with those from other methods such as a Graduated Cylindrical Shell model and a geometrical triangulation method.

Chemokines in the balance: maintenance of homeostasis and protection at CNS barriers

Directory of Open Access Journals (Sweden)

Jessica L Williams

2014-05-01

Full Text Available In the adult central nervous system (CNS, chemokines and their receptors are involved in developmental, physiological and pathological processes. Although most lines of investigation focus on their ability to induce the migration of cells, recent studies indicate that chemokines also promote cellular interactions and activate signaling pathways that maintain CNS homeostatic functions. Many homeostatic chemokines are expressed on the vasculature of the blood brain barrier including CXCL12, CCL19, CCL20, and CCL21. While endothelial cell expression of these chemokines is known to regulate the entry of leukocytes into the CNS during immunosurveillance, new data indicate that CXCL12 is also involved in diverse cellular activities including adult neurogenesis and neuronal survival, having an opposing role to the homeostatic chemokine, CXCL14, which appears to regulate synaptic inputs to neural precursors. Neuronal expression of CX3CL1, yet another homeostatic chemokine that promotes neuronal survival and communication with microglia, is partly regulated by CXCL12. Regulation of CXCL12 is unique in that it may regulate its own expression levels via binding to its scavenger receptor CXCR7/ACKR3. In this review, we explore the diverse roles of these and other homeostatic chemokines expressed within the CNS, including the possible implications of their dysfunction as a cause of neurologic disease.

Dynamic of CSF and serum biomarkers in HIV-1 subtype C encephalitis with CNS genetic compartmentalization-case study.

Science.gov (United States)

de Almeida, Sergio M; Rotta, Indianara; Ribeiro, Clea E; Oliveira, Michelli F; Chaillon, Antoine; de Pereira, Ana Paula; Cunha, Ana Paula; Zonta, Marise; Bents, Joao França; Raboni, Sonia M; Smith, Davey; Letendre, Scott; Ellis, Ronald J

2017-06-01

Despite the effective suppression of viremia with antiretroviral therapy, HIV can still replicate in the central nervous system (CNS). This was a longitudinal study of the cerebrospinal fluid (CSF) and serum dynamics of several biomarkers related to inflammation, the blood-brain barrier, neuronal injury, and IgG intrathecal synthesis in serial samples of CSF and serum from a patient infected with HIV-1 subtype C with CNS compartmentalization.The phylogenetic analyses of plasma and CSF samples in an acute phase using next-generation sequencing and F-statistics analysis of C2-V3 haplotypes revealed distinct compartmentalized CSF viruses in paired CSF and peripheral blood mononuclear cell samples. The CSF biomarker analysis in this patient showed that symptomatic CSF escape is accompanied by CNS inflammation, high levels of cell and humoral immune biomarkers, CNS barrier dysfunction, and an increase in neuronal injury biomarkers with demyelization. Independent and isolated HIV replication can occur in the CNS, even in HIV-1 subtype C, leading to compartmentalization and development of quasispecies distinct from the peripheral plasma. These immunological aspects of the HIV CNS escape have not been described previously. To our knowledge, this is the first report of CNS HIV escape and compartmentalization in HIV-1 subtype C.

Exact cone beam CT with a spiral scan

International Nuclear Information System (INIS)

Tam, K.C.; Samarasekera, S.; Sauer, F.

1998-01-01

A method is developed which makes it possible to scan and reconstruct an object with cone beam x-rays in a spiral scan path with area detectors much shorter than the length of the object. The method is mathematically exact. If only a region of interest of the object is to be imaged, a top circle scan at the top level of the region of interest and a bottom circle scan at the bottom level of the region of interest are added. The height of the detector is required to cover only the distance between adjacent turns in the spiral projected at the detector. To reconstruct the object, the Radon transform for each plane intersecting the object is computed from the totality of the cone beam data. This is achieved by suitably combining the cone beam data taken at different source positions on the scan path; the angular range of the cone beam data required at each source position can be determined easily with a mask which is the spiral scan path projected on the detector from the current source position. The spiral scan algorithm has been successfully validated with simulated cone beam data. (author)

Drug induced increases in CNS dopamine alter monocyte, macrophage and T cell functions: implications for HAND

Science.gov (United States)

Gaskill, Peter J.; Calderon, Tina M.; Coley, Jacqueline S.; Berman, Joan W.

2013-01-01

Central nervous system (CNS) complications resulting from HIV infection remain a major public health problem as individuals live longer due to the success of combined antiretroviral therapy (cART). As many as 70% of HIV infected people have HIV associated neurocognitive disorders (HAND). Many HIV infected individuals abuse drugs, such as cocaine, heroin or methamphetamine, that may be important cofactors in the development of HIV CNS disease. Despite different mechanisms of action, all drugs of abuse increase extracellular dopamine in the CNS. The effects of dopamine on HIV neuropathogenesis are not well understood, and drug induced increases in CNS dopamine may be a common mechanism by which different types of drugs of abuse impact the development of HAND. Monocytes and macrophages are central to HIV infection of the CNS and to HAND. While T cells have not been shown to be a major factor in HIV-associated neuropathogenesis, studies indicate that T cells may play a larger role in the development of HAND in HIV infected drug abusers. Drug induced increases in CNS dopamine may dysregulate functions of, or increase HIV infection in, monocytes, macrophages and T cells in the brain. Thus, characterizing the effects of dopamine on these cells is important for understanding the mechanisms that mediate the development of HAND in drug abusers. PMID:23456305

Clearance of an immunosuppressive virus from the CNS coincides with immune reanimation and diversification

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McGavern Dorian B

2007-06-01

Full Text Available Abstract Once a virus infection establishes persistence in the central nervous system (CNS, it is especially difficult to eliminate from this specialized compartment. Therefore, it is of the utmost importance to fully understand scenarios during which a persisting virus is ultimately purged from the CNS by the adaptive immune system. Such a scenario can be found following infection of adult mice with an immunosuppressive variant of lymphocytic choriomeningitis virus (LCMV referred to as clone 13. In this study we demonstrate that following intravenous inoculation, clone 13 rapidly infected peripheral tissues within one week, but more slowly inundated the entire brain parenchyma over the course of a month. During the establishment of persistence, we observed that genetically tagged LCMV-specific cytotoxic T lymphocytes (CTL progressively lost function; however, the severity of this loss in the CNS was never as substantial as that observed in the periphery. One of the most impressive features of this model system is that the peripheral T cell response eventually regains functionality at ~60–80 days post-infection, and this was associated with a rapid decline in virus from the periphery. Coincident with this "reanimation phase" was a massive influx of CD4 T and B cells into the CNS and a dramatic reduction in viral distribution. In fact, olfactory bulb neurons served as the last refuge for the persisting virus, which was ultimately purged from the CNS within 200 days post-infection. These data indicate that a functionally revived immune response can prevail over a virus that establishes widespread presence both in the periphery and brain parenchyma, and that therapeutic enhancement of an existing response could serve as an effective means to thwart long term CNS persistence.

Imaging aspects of neurologic emergencies in children treated for non-CNS malignancies

International Nuclear Information System (INIS)

Kaste, S.C.; Langston, J.; Rodriguez-Galindo, C.; Furman, W.L.; Thompson, S.J.

2000-01-01

There is a paucity of radiologic literature addressing neurologic emergencies in children receiving therapy for non-CNS primary malignancies. In the acute setting, many of these children present to local community hospitals. This pictorial is from a single institutional experience describing the spectrum of neurologic emergencies seen in children with non-CNS cancers. We hope to familiarize pediatric radiologists with these entities in order to expedite diagnosis, facilitate treatment, and minimize morbity and mortality that may be associated with these complications. (orig.)

Light-cone averaging in cosmology: formalism and applications

International Nuclear Information System (INIS)

Gasperini, M.; Marozzi, G.; Veneziano, G.; Nugier, F.

2011-01-01

We present a general gauge invariant formalism for defining cosmological averages that are relevant for observations based on light-like signals. Such averages involve either null hypersurfaces corresponding to a family of past light-cones or compact surfaces given by their intersection with timelike hypersurfaces. Generalized Buchert-Ehlers commutation rules for derivatives of these light-cone averages are given. After introducing some adapted ''geodesic light-cone'' coordinates, we give explicit expressions for averaging the redshift to luminosity-distance relation and the so-called ''redshift drift'' in a generic inhomogeneous Universe

Metallothionein-1+2 protect the CNS after a focal brain injury

DEFF Research Database (Denmark)

Giralt, Mercedes; Penkowa, Milena; Lago, Natalia

2002-01-01

We have evaluated the physiological relevance of metallothionein-1+2 (MT-1+2) in the CNS following damage caused by a focal cryolesion onto the cortex. In comparison to normal mice, transgenic mice overexpressing the MT-1 isoform (TgMTI* mice) showed a significant decrease of the number...... dramatically reduced the cryolesion-induced oxidative stress and neuronal apoptosis. Remarkably, these effects were also obtained by the intraperitoneal administration of MT-2 to both normal and MT-1+2 knock-out mice. These results fully support the notion that MT-1+2 are essential in the CNS for coping...

The mastermind approach to CNS drug therapy: translational prediction of human brain distribution, target site kinetics, and therapeutic effects

OpenAIRE

de Lange, Elizabeth CM

2013-01-01

Despite enormous advances in CNS research, CNS disorders remain the world?s leading cause of disability. This accounts for more hospitalizations and prolonged care than almost all other diseases combined, and indicates a high unmet need for good CNS drugs and drug therapies. Following dosing, not only the chemical properties of the drug and blood?brain barrier (BBB) transport, but also many other processes will ultimately determine brain target site kinetics and consequently the CNS effects. ...

Tokay gecko photoreceptors achieve rod-like physiology with cone-like proteins.

Science.gov (United States)

Zhang, Xue; Wensel, Theodore G; Yuan, Ching

2006-01-01

The retinal photoreceptors of the nocturnal Tokay gecko (Gekko gekko) consist exclusively of rods by the criteria of morphology and key features of their light responses. Unlike cones, they display robust photoresponses and have relatively slow recovery times. Nonetheless, the major and minor visual pigments identified in gecko rods are of the cone type by sequence and spectroscopic behavior. In the ongoing search for the molecular bases for the physiological differences between cones and rods, we have characterized the molecular biology and biochemistry of the gecko rod phototransduction cascade. We have cloned cDNAs encoding all or part of major protein components of the phototransduction cascade by RT-PCR with degenerate oligonucleotides designed to amplify cone- or rod-like sequences. For all proteins examined we obtained only cone-like and never rod-like sequences. The proteins identified include transducin alpha (Galphat), phosphodiesterase (PDE6) catalytic and inhibitory subunits, cyclic nucleotide-gated channel (CNGalpha) and arrestin. We also cloned cDNA encoding gecko RGS9-1 (Regulator of G Protein Signaling 9, splice variant 1), which is expressed in both rods and cones of all species studied but is typically found at 10-fold higher concentrations in cones, and found that gecko rods contain slightly lower RGS9-1 levels than mammalian rods. Furthermore, we found that the levels of GTPase accelerating protein (GAP) activity and cyclic GMP (cGMP) phosphodiesterase activity were similar in gecko and mammalian rods. These results place substantial constraints on the critical changes needed to convert a cone into a rod in the course of evolution: The many features of phototransduction molecules conserved between those expressed in gecko rods and those expressed in cones cannot explain the physiological differences, whereas the higher levels of RGS9-1 and GAP activity in cones are likely among the essential requirements for the rapid photoresponses of cones.

CNS recruitment of CD8+ T lymphocytes specific for a peripheral virus infection triggers neuropathogenesis during polymicrobial challenge.

Directory of Open Access Journals (Sweden)

Christine M Matullo

2011-12-01

Full Text Available Although viruses have been implicated in central nervous system (CNS diseases of unknown etiology, including multiple sclerosis and amyotrophic lateral sclerosis, the reproducible identification of viral triggers in such diseases has been largely unsuccessful. Here, we explore the hypothesis that viruses need not replicate in the tissue in which they cause disease; specifically, that a peripheral infection might trigger CNS pathology. To test this idea, we utilized a transgenic mouse model in which we found that immune cells responding to a peripheral infection are recruited to the CNS, where they trigger neurological damage. In this model, mice are infected with both CNS-restricted measles virus (MV and peripherally restricted lymphocytic choriomeningitis virus (LCMV. While infection with either virus alone resulted in no illness, infection with both viruses caused disease in all mice, with ∼50% dying following seizures. Co-infection resulted in a 12-fold increase in the number of CD8+ T cells in the brain as compared to MV infection alone. Tetramer analysis revealed that a substantial proportion (>35% of these infiltrating CD8+ lymphocytes were LCMV-specific, despite no detectable LCMV in CNS tissues. Mechanistically, CNS disease was due to edema, induced in a CD8-dependent but perforin-independent manner, and brain herniation, similar to that observed in mice challenged intracerebrally with LCMV. These results indicate that T cell trafficking can be influenced by other ongoing immune challenges, and that CD8+ T cell recruitment to the brain can trigger CNS disease in the apparent absence of cognate antigen. By extrapolation, human CNS diseases of unknown etiology need not be associated with infection with any particular agent; rather, a condition that compromises and activates the blood-brain barrier and adjacent brain parenchyma can render the CNS susceptible to pathogen-independent immune attack.

Analysis of macular cone photoreceptors in a case of occult macular dystrophy

Directory of Open Access Journals (Sweden)

Tojo N

2013-05-01

Full Text Available Naoki Tojo Tomoko Nakamura Hironori Ozaki Miyako Oka Toshihiko Oiwake Atsushi HayashiDepartment of Ophthalmology, University of Toyama, Toyama, JapanPurpose: To investigate changes in cone photoreceptors with adaptive optics (AO fundus imaging and spectral domain optical coherence tomography (SD-OCT in a case of occult macular dystrophy (OMD.Patient and methods: Both eyes of a 42-year-old woman diagnosed with OMD were examined. We used an AO fundus camera to obtain images of cone photoreceptors in the macula of the OMD subject and five healthy control subjects. Correlations between the AO images and the SD-OCT images were examined. Cone photoreceptors in eight areas in the macula of OMD and healthy control subjects were analyzed and compared.Results: SD-OCT showed a loss of the cone outer-segment tips line outside of the fovea in both eyes of the subject with OMD. The left eye with decreased visual acuity showed a discontinuous photoreceptor inner-segment and outer-segment line and cone outer-segment tips line at the fovea in SD-OCT and loss of cone mosaics as a dark spot in the AO image. In panoramic AO images and cone-density maps, less cone density was observed in a ring-like region outside the fovea than in the peripheral retina. In most of the areas examined, the cone densities were lower in the OMD eyes than in the healthy control eyes.Conclusions: Cone densities in the macula of the OMD patient were greatly decreased. AO images were found to be useful to evaluate morphologic changes in cone photoreceptors in patients with OMD.Keywords: occult macular dystrophy, adaptive optics, cone photoreceptor, cone analysis, optical coherence tomography

A unified analysis of FBP-based algorithms in helical cone-beam and circular cone- and fan-beam scans

International Nuclear Information System (INIS)

Pan Xiaochuan; Xia Dan; Zou Yu; Yu Lifeng

2004-01-01

A circular scanning trajectory is and will likely remain a popular choice of trajectory in computed tomography (CT) imaging because it is easy to implement and control. Filtered-backprojection (FBP)-based algorithms have been developed previously for approximate and exact reconstruction of the entire image or a region of interest within the image in circular cone-beam and fan-beam cases. Recently, we have developed a 3D FBP-based algorithm for image reconstruction on PI-line segments in a helical cone-beam scan. In this work, we demonstrated that the 3D FBP-based algorithm indeed provided a rather general formulation for image reconstruction from divergent projections (such as cone-beam and fan-beam projections). On the basis of this formulation we derived new approximate or exact algorithms for image reconstruction in circular cone-beam or fan-beam scans, which can be interpreted as special cases of the helical scan. Existing algorithms corresponding to the derived algorithms were identified. We also performed a preliminary numerical study to verify our theoretical results in each of the cases. The results in the work can readily be generalized to other non-circular trajectories

Cancers of the Brain and CNS: Global Patterns and Trends in Incidence.

Science.gov (United States)

Mortazavi, S M J; Mortazavi, S A R; Paknahad, M

2018-03-01

Miranda-Filho et al. in their recently published paper entitled "Cancers of the brain and CNS: global patterns and trends in incidence" provided a global status report of the geographic and temporal variations in the incidence of brain and CNS cancers in different countries across continents worldwide. While the authors confirm the role of genetic risk factors and ionizing radiation exposures, they claimed that no firm conclusion could be drawn about the role of exposure to non-ionizing radiation. The paper authored by Miranda-Filho et al. not only addresses a challenging issue, it can be considered as a good contribution in the field of brain and CNS cancers. However, our correspondence addresses a basic shortcoming of this paper about the role of electromagnetic fields and cancers and provides evidence showing that exposure to radiofrequency electromagnetic fields (RF-EMFs), at least at high levels and long durations, can increases the risk of cancer.

Determination of HCME 3-D parameters using a full ice-cream cone model

Science.gov (United States)

Na, Hyeonock; Moon, Yong-Jae; Lee, Harim

2016-05-01

It is very essential to determine three dimensional parameters (e.g., radial speed, angular width, source location) of Coronal Mass Ejections (CMEs) for space weather forecast. Several cone models (e.g., an elliptical cone model, an ice-cream cone model, an asymmetric cone model) have been examined to estimate these parameters. In this study, we investigate which cone type is close to a halo CME morphology using 26 CMEs: halo CMEs by one spacecraft (SOHO or STEREO-A or B) and as limb CMEs by the other ones. From cone shape parameters of these CMEs such as their front curvature, we find that near full ice-cream cone type CMEs are much closer to observations than shallow ice-cream cone type CMEs. Thus we develop a new cone model in which a full ice-cream cone consists of many flat cones with different heights and angular widths. This model is carried out by the following steps: (1) construct a cone for given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, and (4) minimize the difference between the estimated projection speeds with the observed ones. By applying this model to 12 SOHO/LASCO halo CMEs, we find that 3-D parameters from our method are similar to those from other stereoscopic methods (a geometrical triangulation method and a Graduated Cylindrical Shell model) based on multi-spacecraft data. We are developing a general ice-cream cone model whose front shape is a free parameter determined by observations.

The uniqueness of the solution of cone-like inversion models for halo CMEs

Science.gov (United States)

Zhao, X. P.

2006-12-01

Most of elliptic halo CMEs are believed to be formed by the Thompson scattering of the photospheric light by the 3-D cone-like shell of the CME plasma. To obtain the real propagation direction and angular width of the halo CMEs, such cone-like inversion models as the circular cone, the elliptic cone and the ice-cream cone models have been suggested recently. Because the number of given parameters that are used to characterize 2-D elliptic halo CMEs observed by one spacecraft are less than the number of unknown parameters that are used to characterize the 3-D elliptic cone model, the solution of the elliptic cone model is not unique. Since it is difficult to determine whether or not an observed halo CME is formed by an circular cone or elliptic cone shell, the solution of circular cone model may often be not unique too. To fix the problem of the uniqueness of the solution of various 3-D cone-like inversion models, this work tries to develop the algorithm for using the data from multi-spacecraft, such as the STEREO A and B, and the Solar Sentinels.

Case of Unilateral Peripheral Cone Dysfunction

Directory of Open Access Journals (Sweden)

Yujin Mochizuki

2012-05-01

Full Text Available Purpose: Peripheral cone dystrophy is a subgroup of cone dystrophy, and only 4 cases have been reported. We present a patient with unilateral peripheral cone dysfunction and report the functional changes determined by electrophysiological tests and ultrastructural changes determined by spectral domain optical coherence tomography (SD-OCT. Case: A 34-year-old woman complained of blurred vision in both eyes. Our examination showed that her visual acuity was 0.05 OD and 0.2 OS. A relative afferent pupillary defect was present in her right eye. The results of slit-lamp examination, ophthalmoscopy, and fluorescein angiography were normal except for pallor of the right optic disc. SD-OCT showed a diffuse thinning of the retina in the posterior pole of the right eye. A severe constriction of the visual fields was found in both eyes but more in the right eye. The photopic full-field electroretinograms (ERGs were reduced in the right eye but normal in the left eye. The multifocal ERGs were severely reduced throughout the visual field except in the central area of the right eye. The multifocal ERGs from the left eye were normal. The pattern visual evoked responses were within the normal range in both eyes. She had a 5-year history of sniffing paint thinner. Results: Although the visual dysfunction was initially suspected to be due to psychological problems from the results of subjective tests, objective tests indicated a peripheral cone dysfunction in the right eye. The pathophysiological mechanism and the relationship with thinner sniffing were not determined. Conclusions: Our findings indicate that peripheral cone dysfunction can occur unilaterally. Electrophysiology and SD-OCT are valuable tests to perform to determine the pathogenesis of unusual ocular findings objectively.

Human Blue Cone Opsin Regeneration Involves Secondary Retinal Binding with Analog Specificity.

Science.gov (United States)

Srinivasan, Sundaramoorthy; Fernández-Sampedro, Miguel A; Morillo, Margarita; Ramon, Eva; Jiménez-Rosés, Mireia; Cordomí, Arnau; Garriga, Pere

2018-03-27

Human color vision is mediated by the red, green, and blue cone visual pigments. Cone opsins are G-protein-coupled receptors consisting of an opsin apoprotein covalently linked to the 11-cis-retinal chromophore. All visual pigments share a common evolutionary origin, and red and green cone opsins exhibit a higher homology, whereas blue cone opsin shows more resemblance to the dim light receptor rhodopsin. Here we show that chromophore regeneration in photoactivated blue cone opsin exhibits intermediate transient conformations and a secondary retinoid binding event with slower binding kinetics. We also detected a fine-tuning of the conformational change in the photoactivated blue cone opsin binding site that alters the retinal isomer binding specificity. Furthermore, the molecular models of active and inactive blue cone opsins show specific molecular interactions in the retinal binding site that are not present in other opsins. These findings highlight the differential conformational versatility of human cone opsin pigments in the chromophore regeneration process, particularly compared to rhodopsin, and point to relevant functional, unexpected roles other than spectral tuning for the cone visual pigments. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Accessibility analysis in manufacturing processes using visibility cones

Institute of Scientific and Technical Information of China (English)

尹周平; 丁汉; 熊有伦

2002-01-01

Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing processes.After exploring the relations among approachability,accessibility and visibility,a general method for accessibility analysis using visibility cones (VC) is proposed.With the definition of VC of a point,three kinds of visibility of a feature,namely complete visibility cone (CVC),partial visibility cone (PVC) and local visibility cone (LVC),are defined.A novel approach to computing VCs is formulated by identifying C-obstacles in the C-space,for which a general and efficient algorithm is proposed and implemented by making use of visibility culling.Lastly,we discuss briefly how to realize accessibility analysis in numerically controlled (NC) machining planning,coordinate measuring machines (CMMs) inspection planning and assembly sequence planning with the proposed methods.

Testing the reliability of ice-cream cone model

Science.gov (United States)

Pan, Zonghao; Shen, Chenglong; Wang, Chuanbing; Liu, Kai; Xue, Xianghui; Wang, Yuming; Wang, Shui

2015-04-01

Coronal Mass Ejections (CME)'s properties are important to not only the physical scene itself but space-weather prediction. Several models (such as cone model, GCS model, and so on) have been raised to get rid of the projection effects within the properties observed by spacecraft. According to SOHO/ LASCO observations, we obtain the 'real' 3D parameters of all the FFHCMEs (front-side full halo Coronal Mass Ejections) within the 24th solar cycle till July 2012, by the ice-cream cone model. Considering that the method to obtain 3D parameters from the CME observations by multi-satellite and multi-angle has higher accuracy, we use the GCS model to obtain the real propagation parameters of these CMEs in 3D space and compare the results with which by ice-cream cone model. Then we could discuss the reliability of the ice-cream cone model.

Prescriptionless light-cone integrals

International Nuclear Information System (INIS)

Suzuki, A.T.; Schmidt, A.G.M.

2000-01-01

Perturbative quantum gauge field theory as seen within the perspective of physical gauge choices such as the light-cone gauge entails the emergence of troublesome poles of the type (k.n) -α in the Feynman integrals. These come from the boson field propagator, where α=1,2,.. and n μ is the external arbitrary four-vector that defines the gauge properly. This becomes an additional hurdle in the computation of Feynman diagrams, since any graph containing internal boson lines will inevitably produce integrands with denominators bearing the characteristic gauge-fixing factor. How one deals with them has been the subject of research over decades, and several prescriptions have been suggested and tried in the course of time, with failures and successes. However, a more recent development at this fronteer which applies the negative dimensional technique to compute light-cone Feynman integrals shows that we can altogether dispense with prescriptions to perform the calculations. An additional bonus comes to us attached to this new technique, in that not only it renders the light-cone prescriptionless but, by the very nature of it, it can also dispense with decomposition formulas or partial fractioning tricks used in the standard approach to separate pole products of the type (k.n) -α [(k-p).n] -β (β=1,2,..). In this work we demonstrate how all this can be done. (orig.)

Natural host genetic resistance to lentiviral CNS disease: a neuroprotective MHC class I allele in SIV-infected macaques.

Directory of Open Access Journals (Sweden)

Joseph L Mankowski

Full Text Available Human immunodeficiency virus (HIV infection frequently causes neurologic disease even with anti-retroviral treatment. Although associations between MHC class I alleles and acquired immunodeficiency syndrome (AIDS have been reported, the role MHC class I alleles play in restricting development of HIV-induced organ-specific diseases, including neurologic disease, has not been characterized. This study examined the relationship between expression of the MHC class I allele Mane-A*10 and development of lentiviral-induced central nervous system (CNS disease using a well-characterized simian immunodeficiency (SIV/pigtailed macaque model. The risk of developing CNS disease (SIV encephalitis was 2.5 times higher for animals that did not express the MHC class I allele Mane-A*10 (P = 0.002; RR = 2.5. Animals expressing the Mane-A*10 allele had significantly lower amounts of activated macrophages, SIV RNA, and neuronal dysfunction in the CNS than Mane-A*10 negative animals (P<0.001. Mane-A*10 positive animals with the highest CNS viral burdens contained SIV gag escape mutants at the Mane-A*10-restricted KP9 epitope in the CNS whereas wild type KP9 sequences dominated in the brain of Mane-A*10 negative animals with comparable CNS viral burdens. These concordant findings demonstrate that particular MHC class I alleles play major neuroprotective roles in lentiviral-induced CNS disease.

Alopecia associated with unexpected leakage from electron cone

Energy Technology Data Exchange (ETDEWEB)

Wen, B.C.; Pennington, E.C.; Hussey, D.H.; Jani, S.K.

1989-06-01

Excessive irradiation due to unexpected leakage was found on a patient receiving electron beam therapy. The cause of this leakage was analyzed and the amount of leakage was measured for different electron beam energies. The highest leakage occurred with a 6 x 6 cm cone using a 12 MeV electron beam. The leakage dose measured along the side of the cone could be as great as 40%. Until the cones are modified or redesigned, it is advised that all patient setups be carefully reviewed to assure that no significant patient areas are in the side scatter region.

Development of pits and cones on ion bombarded copper

International Nuclear Information System (INIS)

Tanovic, L.A.; Carter, G.; Nobes, M.J.; Whitton, I.L.; Williams, J.S.

1980-01-01

The formation of pits and cones on Ar ion bombarded copper has been studied. Carefully polished surfaces of large grained 99.999% pure copper crystals have been bombarded at normal incidence with 40 keV argon ions. The cone formation has been investigated for annealed and non-annealed crystals at room temperature and at 30 K and in the case of monocrystal and polycrystal samples. Although in the most other studies the presence of impurities is as a necessary condition for generation of cones and pits the obtained experimental results show that under certain conditions these features are formed on clean surfaces. It is shown that the dominant parameter in the production of cones on copper is the crystal orientation [ru

CD11c-expressing cells affect Treg behavior in the meninges during CNS infection1

Science.gov (United States)

O’Brien, Carleigh A.; Overall, Christopher; Konradt, Christoph; O’Hara Hall, Aisling C.; Hayes, Nikolas W.; Wagage, Sagie; John, Beena; Christian, David A.; Hunter, Christopher A.; Harris, Tajie H.

2017-01-01

Treg cells play an important role in the CNS during multiple infections as well as autoimmune inflammation, but the behavior of this cell type in the CNS has not been explored. In mice, infection with Toxoplasma gondii leads to a Th1-polarized parasite-specific effector T cell response in the brain. Similarly, the Treg cells in the CNS during T. gondii infection are Th1-polarized, exemplified by T-bet, CXCR3, and IFN-γ expression. Unlike effector CD4+ T cells, an MHC Class II tetramer reagent specific for T. gondii did not recognize Treg cells isolated from the CNS. Likewise, TCR sequencing revealed minimal overlap in TCR sequence between effector and regulatory T cells in the CNS. Whereas effector T cells are found in the brain parenchyma where parasites are present, Treg cells were restricted to the meninges and perivascular spaces. The use of intravital imaging revealed that activated CD4+ T cells within the meninges were highly migratory, while Treg cells moved more slowly and were found in close association with CD11c+ cells. To test whether the behavior of Tregs in the meninges is influenced by interactions with CD11c+ cells, mice were treated with anti-LFA-1 antibodies to reduce the number of CD11c+ cells in this space. The anti-LFA-1 treatment led to fewer contacts between Tregs and the remaining CD11c+ cells and increased the speed of Treg cell migration. These data suggest that Treg cells are anatomically restricted within the CNS and the interaction with CD11c+ populations regulates their local behavior during T. gondii infection. PMID:28389591

In vivo human apolipoprotein E isoform fractional turnover rates in the CNS.

Directory of Open Access Journals (Sweden)

Kristin R Wildsmith

Full Text Available Apolipoprotein E (ApoE is the strongest genetic risk factor for Alzheimer's disease and has been implicated in the risk for other neurological disorders. The three common ApoE isoforms (ApoE2, E3, and E4 each differ by a single amino acid, with ApoE4 increasing and ApoE2 decreasing the risk of Alzheimer's disease (AD. Both the isoform and amount of ApoE in the brain modulate AD pathology by altering the extent of amyloid beta (Aβ peptide deposition. Therefore, quantifying ApoE isoform production and clearance rates may advance our understanding of the role of ApoE in health and disease. To measure the kinetics of ApoE in the central nervous system (CNS, we applied in vivo stable isotope labeling to quantify the fractional turnover rates of ApoE isoforms in 18 cognitively-normal adults and in ApoE3 and ApoE4 targeted-replacement mice. No isoform-specific differences in CNS ApoE3 and ApoE4 turnover rates were observed when measured in human CSF or mouse brain. However, CNS and peripheral ApoE isoform turnover rates differed substantially, which is consistent with previous reports and suggests that the pathways responsible for ApoE metabolism are different in the CNS and the periphery. We also demonstrate a slower turnover rate for CSF ApoE than that for amyloid beta, another molecule critically important in AD pathogenesis.

Elevated interferon-gamma in CNS inflammatory disease: a potential complication for bone marrow reconstitution in MS

DEFF Research Database (Denmark)

Hassan-Zahraee, M; Tran, E H; Bourbonnière, L

2000-01-01

but levels were higher in IFNgamma transgenics. BM transplantation into IFNgamma-deficient recipients also had a high failure rate. Transplants of BM from mice lacking expression of IFNgamma-receptor failed, whereas IFNgamma-deficient grafts survived, suggesting that IFNgamma response status of the graft can......Bone marrow transplantation (BMT) is increasingly used to treat Multiple Sclerosis (MS) a CNS inflammatory disease with elevated CNS and systemic IFNgamma levels. We wished to determine the effect of IFNgamma on BM graft survival in a transgenic mouse model for chronic MS. BM transplantation...... into transgenic mice which express elevated levels of IFNgamma in the CNS was unsuccessful. By contrast, there was 100% survival of even fully allogeneic, T-depleted transplants to transgenics that over express TNFalpha in the CNS, using the same MBP promoter. IFNgamma was detectable in spleen of irradiated mice...

Formation of shatter cones by symmetric fracture bifurcation: Phenomenological modeling and validation

Science.gov (United States)

Kenkmann, Thomas; Hergarten, Stefan; Kuhn, Thomas; Wilk, Jakob

2016-08-01

Several models of shatter cone formation require a heterogeneity at the cone apex of high impedance mismatch to the surrounding bulk rock. This heterogeneity is the source of spherically expanding waves that interact with the planar shock front or the following release wave. While these models are capable of explaining the overall conical shape of shatter cones, they are not capable of explaining the subcone structure and the diverging and branching striations that characterize the surface of shatter cones and lead to the so-called horse-tailing effect. Here, we use the hierarchical arrangement of subcone ridges of shatter cone surfaces as key for understanding their formation. Tracing a single subcone ridge from its apex downward reveals that each ridge branches after some distance into two symmetrically equivalent subcone ridges. This pattern is repeated to form new branches. We propose that subcone ridges represent convex-curved fracture surfaces and their intersection corresponds to the bifurcation axis. The characteristic diverging striations are interpreted as the intersection lineations delimiting each subcone. Multiple symmetric crack branching is the result of rapid fracture propagation that may approach the Raleigh wave speed. We present a phenomenological model that fully constructs the shatter cone geometry to any order. The overall cone geometry including apex angle of the enveloping cone and the degree of concavity (horse-tailing) is largely governed by the convexity of the subcone ridges. Straight cones of various apical angles, constant slope, and constant bifurcation angles form if the subcone convexity is low (30°). Increasing subcone convexity leads to a stronger horse-tailing effect and the bifurcation angles increase with increasing distance from the enveloping cone apex. The model predicts possible triples of enveloping cone angle, bifurcation angle, and subcone angle. Measurements of these quantities on four shatter cones from different

Direct cone beam SPECT reconstruction with camera tilt

International Nuclear Information System (INIS)

Jianying Li; Jaszczak, R.J.; Greer, K.L.; Coleman, R.E.; Zongjian Cao; Tsui, B.M.W.

1993-01-01

A filtered backprojection (FBP) algorithm is derived to perform cone beam (CB) single-photon emission computed tomography (SPECT) reconstruction with camera tilt using circular orbits. This algorithm reconstructs the tilted angle CB projection data directly by incorporating the tilt angle into it. When the tilt angle becomes zero, this algorithm reduces to that of Feldkamp. Experimentally acquired phantom studies using both a two-point source and the three-dimensional Hoffman brain phantom have been performed. The transaxial tilted cone beam brain images and profiles obtained using the new algorithm are compared with those without camera tilt. For those slices which have approximately the same distance from the detector in both tilt and non-tilt set-ups, the two transaxial reconstructions have similar profiles. The two-point source images reconstructed from this new algorithm and the tilted cone beam brain images are also compared with those reconstructed from the existing tilted cone beam algorithm. (author)

Bright and durable field emission source derived from refractory taylor cones

Science.gov (United States)

Hirsch, Gregory

2016-12-20

A method of producing field emitters having improved brightness and durability relying on the creation of a liquid Taylor cone from electrically conductive materials having high melting points. The method calls for melting the end of a wire substrate with a focused laser beam, while imposing a high positive potential on the material. The resulting molten Taylor cone is subsequently rapidly quenched by cessation of the laser power. Rapid quenching is facilitated in large part by radiative cooling, resulting in structures having characteristics closely matching that of the original liquid Taylor cone. Frozen Taylor cones thus obtained yield desirable tip end forms for field emission sources in electron beam applications. Regeneration of the frozen Taylor cones in-situ is readily accomplished by repeating the initial formation procedures. The high temperature liquid Taylor cones can also be employed as bright ion sources with chemical elements previously considered impractical to implement.

CNS-targets in control of energy and glucose homeostasis.

Science.gov (United States)

Kleinridders, André; Könner, A Christine; Brüning, Jens C

2009-12-01

The exceeding efforts in understanding the signals initiated by nutrients and hormones in the central nervous system (CNS) to regulate glucose and energy homeostasis have largely revolutionized our understanding of the neurocircuitry in control of peripheral metabolism. The ability of neurons to sense nutrients and hormones and to adopt a coordinated response to these signals is of crucial importance in controlling food intake, energy expenditure, glucose and lipid metabolism. Anatomical lesion experiments, pharmacological inhibition of signaling pathways, and, more recently, the analysis of conditional mouse mutants with modifications of hormone and nutrient signaling in defined neuronal populations have broadened our understanding of these complex neurocircuits. This review summarizes recent findings regarding the role of the CNS in sensing and transmitting nutritional and hormonal signals to control energy and glucose homeostasis and aims to define them as potential novel drug targets for the treatment of obesity and type 2 diabetes mellitus.

Cone pigments in a North American marsupial, the opossum (Didelphis virginiana).

Science.gov (United States)

Jacobs, Gerald H; Williams, Gary A

2010-05-01

Only two of the four cone opsin gene families found in vertebrates are represented in contemporary eutherian and marsupial species. Recent genetic studies of two species of South American marsupial detected the presence of representatives from two of the classes of cone opsin genes and the structures of these genes predicted cone pigments with respective peaks in the ultraviolet and long-wavelength portions of the spectrum. The Virginia opossum (Didelphis virginiana), a profoundly nocturnal animal, is the only marsupial species found in North America. The prospects for cone-based vision in this species were examined through recordings of the electroretinogram (ERG), a commonly examined retinal response to photic stimulation. Recorded under flickering-light conditions that elicit signals from cone photoreceptors, the spectral sensitivity of the opossum eye is well accounted for by contributions from the presence of a single cone pigment having peak absorption at 561-562 nm. A series of additional experiments that employed various chromatic adaptation paradigms were conducted in a search for possible contributions from a second (short-wavelength sensitive) cone pigment. We found no evidence that such a mechanism contributes to the ERG in this marsupial.

Synergistic effect of nisin and cone essential oil of Metasequoia glyptostroboides Miki ex Hu against Listeria monocytogenes in milk samples.

Science.gov (United States)

Yoon, Jung In; Bajpai, Vivek K; Kang, Sun Chul

2011-01-01

This study was undertaken to evaluate the effect of nisin and cone essential oil of Metasequoia glyptostroboides against Listeria monocytogenes ATCC 19116 inoculated in whole (8%), low (1%) and skim (no fat content) milks. Essential oil at the concentrations of 2% and 5% revealed strong antilisterial effect against L. monocytogenes ATCC 19116 in all categories of milks. Nisin at the concentrations of 250 and 500 IU/ml displayed a remarkable antilisterial effect as compared to the control group. Also, the synergistic combinations of cone essential oil (1% and 2%) and nisin (62.5, 125, 250 and 500 IU/ml) had a remarkable antilisterial activity in all categories of whole, low and skim milks after 14 days. Results of this study indicate that the cone essential oil of M. glyptostroboides might be a useful candidate for using in food industry to control the growth of pathogenic microorganisms. Copyright © 2010 Elsevier Ltd. All rights reserved.

Full Stability of Locally Optimal Solutions in Second-Order Cone Programs

Czech Academy of Sciences Publication Activity Database

Mordukhovich, B. S.; Outrata, Jiří; Sarabi, E.

2014-01-01

Roč. 24, č. 4 (2014), s. 1581-1613 ISSN 1052-6234 R&D Projects: GA ČR GAP402/12/1309 Grant - others:Australian Research Council(AU) DP-12092508; Australian Research Council(AU) DP-110102011; Portuguese Foundation of Science and Technologies(PT) MAT/11109; USA National Science Foundation(US) DMS-1007132 Institutional support: RVO:67985556 Keywords : variational analysis * second-order cone programming * full stability of local minimizers * nondegeneracy * strong regularity * quadratic growth * second-order subdifferentials * coderivatives Subject RIV: BA - General Mathematics Impact factor: 1.829, year: 2014 http://library.utia.cas.cz/separaty/2014/MTR/outrata-0434303.pdf

The Therapeutic Potential of Insulin-Like Growth Factor-1 in Central Nervous System Disorders

Science.gov (United States)

Costales, Jesse; Kolevzon, Alexander

2016-01-01

Central nervous system (CNS) development is a finely tuned process that relies on multiple factors and intricate pathways to ensure proper neuronal differentiation, maturation, and connectivity. Disruption of this process can cause significant impairments in CNS functioning and lead to debilitating disorders that impact motor and language skills, behavior, and cognitive functioning. Recent studies focused on understanding the underlying cellular mechanisms of neurodevelopmental disorders have identified a crucial role for insulin-like growth factor-1 (IGF-1) in normal CNS development. Work in model systems has demonstrated rescue of pathophysiological and behavioral abnormalities when IGF-1 is administered, and several clinical studies have shown promise of efficacy in disorders of the CNS, including autism spectrum disorder (ASD). In this review, we explore the molecular pathways and downstream effects of IGF-1 and summarize the results of completed and ongoing pre-clinical and clinical trials using IGF-1 as a pharmacologic intervention in various CNS disorders. This aim of this review is to provide evidence for the potential of IGF-1 as a treatment for neurodevelopmental disorders and ASD. PMID:26780584

Instantaneous interactions of hadrons on the light cone

International Nuclear Information System (INIS)

Hyer, T.

1994-01-01

Hadron wave functions are most naturally defined in the framework of light-cone quantization, a Hamiltonian formulation quantized at equal light-cone ''time'' τ≡t+z. One feature of the light-cone perturbation theory is the presence of instantaneous interactions, which complicate the consideration of processes involving bound states. We show that these interactions can be written in a simple and general form, parametrized by an instantaneous contribution ψ to the hadronic wave function. We use the rotational invariance of Feynman diagrams to relate this instantaneous piece of the meson wave function to the propagating part, and to obtain constraints relating wave functions and quark fragmentation amplitudes

Mast Cells and Innate Lymphoid Cells: Underappreciated Players in CNS Autoimmune Demyelinating Disease.

Science.gov (United States)

Brown, Melissa A; Weinberg, Rebecca B

2018-01-01

Multiple sclerosis (MS) and its mouse model, experimental autoimmune encephalomyelitis, are autoimmune CNS inflammatory diseases. As a result of a breakdown in the relatively impermeable blood-brain barrier (BBB) in affected individuals, myelin-specific CD4 + and CD8 + T cells gain entry into the immune privileged CNS and initiate myelin, oligodendrocyte, and nerve axon destruction. However, despite the absolute requirement for T cells, there is increasing evidence that innate immune cells also play critical amplifying roles in disease pathogenesis. By modulating the character and magnitude of the myelin-reactive T cell response and regulating BBB integrity, innate cells affect both disease initiation and progression. Two classes of innate cells, mast cells and innate lymphoid cells (ILCs), have been best studied in models of allergic and gastrointestinal inflammatory diseases. Yet, there is emerging evidence that these cell types also exert a profound influence in CNS inflammatory disease. Both cell types are residents within the meninges and can be activated early in disease to express a wide variety of disease-modifying cytokines and chemokines. In this review, we discuss how mast cells and ILCs can have either disease-promoting or -protecting effects on MS and other CNS inflammatory diseases and how sex hormones may influence this outcome. These observations suggest that targeting these cells and their unique mediators can be exploited therapeutically.

Serial brain MRI findings in CNS involvement of familial erythrophagocytic lymphohistiocytosis: a case report

International Nuclear Information System (INIS)

Cho, Kyung Soo; Yoo, Jeong Hyun; Suh, Jeong Soo; Ryu, Kyung Ha; Hong, Ki Sook; Kim, Hak Jin

2002-01-01

Familial erythrophagocytic lymphohistiocytosis is a fatal early childhood disorder characterized by multiorgan lymphohistiocytic infiltration and active hemophagocytosis. Involvement of the central nervous system (CNS) is not uncommon and is characterized by rapidly progressive tissue damage affecting both the gray and white matter. We encountered a case of familial erythrophagocytic lymphohistiocytosis with CNS involvement. Initial T2-weighted MRI of the brain demonstrated high signal intensity in the right thalamus, though after chemotherapy, which led to the relief of neurologic symptoms, this disappeared. After four months. however, the patient's neurologic symptoms recurred, and follow-up T2-weighted MR images showed high signal intensity in the thalami, basal ganglia, and cerebral and cerebellar white matter. Brain MRI is a useful imaging modality for the evaluation of CNS involvement and monitoring the response to treatment

Early Stages of Pulsed-Laser Growth of Silicon Microcolumns and Microcones in Air and SF6

International Nuclear Information System (INIS)

Fowlkes, J.D.; Lowndes, D.H.; Pedraza, A.J.

1999-01-01

Dense arrays of high-aspect-ratio silicon microcolumns and microcones are formed by cumulative nanosecond pulsed excimer laser irradiation of single-crystal silicon in oxidizing atmospheres such as air and SF 6 . Growth of such surface microstructures requires a redeposition model and also involves elements of self-organization. The shape of the microstructures, i.e. straight columns vs steeply sloping cones and connecting walls, is governed by the type and concentration of the oxidizing species, e.g. oxygen vs fluorine. Growth is believed to occur by a catalyst-free VLS (vapor-liquid-solid) mechanism that involves repetitive melting of the tips of the columns/cones and deposition there of the ablated flux of Si-containing vapor. Results are presented of a new investigation of how such different final microstructures as microcolumns or microcones joined by walls nucleate and develop. The changes in silicon surface morphology were systematically determined and compared as the number of pulsed KrF (248 nm) laser shots was increased from 25 to several thousand in both air and SF 6 . The experiments in air and SF 6 reveal significant differences in initial surface cracking and pattern formation. Consequently, local protrusions are first produced and column or cone/wall growth is initiated by different processes and at different rates. Differences in the spatial organization of column or cone/wall growth also are apparent

Chloride equilibrium potential in salamander cones

Directory of Open Access Journals (Sweden)

Bryson Eric J

2004-12-01

Full Text Available Abstract Background GABAergic inhibition and effects of intracellular chloride ions on calcium channel activity have been proposed to regulate neurotransmission from photoreceptors. To assess the impact of these and other chloride-dependent mechanisms on release from cones, the chloride equilibrium potential (ECl was determined in red-sensitive, large single cones from the tiger salamander retinal slice. Results Whole cell recordings were done using gramicidin perforated patch techniques to maintain endogenous Cl- levels. Membrane potentials were corrected for liquid junction potentials. Cone resting potentials were found to average -46 mV. To measure ECl, we applied long depolarizing steps to activate the calcium-activated chloride current (ICl(Ca and then determined the reversal potential for the current component that was inhibited by the Cl- channel blocker, niflumic acid. With this method, ECl was found to average -46 mV. In a complementary approach, we used a Cl-sensitive dye, MEQ, to measure the Cl- flux produced by depolarization with elevated concentrations of K+. The membrane potentials produced by the various high K+ solutions were measured in separate current clamp experiments. Consistent with electrophysiological experiments, MEQ fluorescence measurements indicated that ECl was below -36 mV. Conclusions The results of this study indicate that ECl is close to the dark resting potential. This will minimize the impact of chloride-dependent presynaptic mechanisms in cone terminals involving GABAa receptors, glutamate transporters and ICl(Ca.

Effect of Drainage Conditions on Cone Penetration Testing in Silty Soils

DEFF Research Database (Denmark)

Poulsen, Rikke; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

2011-01-01

This paper discusses the challenges that occur when performing Cone Penetration Tests (CPT) in silty soil due to changes in drainage conditions. In this paper, CPT results from various papers and researchers are collected and interpreted. Results from cone penetrations tests with various penetrat......This paper discusses the challenges that occur when performing Cone Penetration Tests (CPT) in silty soil due to changes in drainage conditions. In this paper, CPT results from various papers and researchers are collected and interpreted. Results from cone penetrations tests with various...

Novel CNS drug discovery and development approach: model-based integration to predict neuro-pharmacokinetics and pharmacodynamics.

Science.gov (United States)

de Lange, Elizabeth C M; van den Brink, Willem; Yamamoto, Yumi; de Witte, Wilhelmus E A; Wong, Yin Cheong

2017-12-01

CNS drug development has been hampered by inadequate consideration of CNS pharmacokinetic (PK), pharmacodynamics (PD) and disease complexity (reductionist approach). Improvement is required via integrative model-based approaches. Areas covered: The authors summarize factors that have played a role in the high attrition rate of CNS compounds. Recent advances in CNS research and drug discovery are presented, especially with regard to assessment of relevant neuro-PK parameters. Suggestions for further improvements are also discussed. Expert opinion: Understanding time- and condition dependent interrelationships between neuro-PK and neuro-PD processes is key to predictions in different conditions. As a first screen, it is suggested to use in silico/in vitro derived molecular properties of candidate compounds and predict concentration-time profiles of compounds in multiple compartments of the human CNS, using time-course based physiology-based (PB) PK models. Then, for selected compounds, one can include in vitro drug-target binding kinetics to predict target occupancy (TO)-time profiles in humans. This will improve neuro-PD prediction. Furthermore, a pharmaco-omics approach is suggested, providing multilevel and paralleled data on systems processes from individuals in a systems-wide manner. Thus, clinical trials will be better informed, using fewer animals, while also, needing fewer individuals and samples per individual for proof of concept in humans.

Physiological and Molecular Characterization of Biosurfactant Producing Endophytic Fungi Xylaria regalis from the Cones of Thuja plicata as a Potent Plant Growth Promoter with Its Potential Application

Directory of Open Access Journals (Sweden)

Mohd Adnan

2018-01-01

Full Text Available Currently, there is an absolute concern for all nations in agricultural productivity to meet growing demands of human population. In recent time, biosurfactants produced by diverse group of microorganisms are used to achieve such demands as it is known for its ecofriendly use in elimination of plant pathogens and for increasing the bioavailability of nutrients for plants. Endophytic fungi are the important source of secondary metabolites and novel bioactive compounds for different biological applications. In the present study, endophytic fungi Xylaria regalis (X. regalis recovered from the cones of Thuja plicata was evaluated for its biosurfactant producing ability and plant growth-promoting abilities through various screening methods and also via its antagonistic activity against phytopathogens like Fusarium oxysporum and Aspergillus niger. In addition, X. regalis was also tested in vivo for a various range of growth parameters in chilli under greenhouse conditions. Significant increase in shoot and root length, dry matter production of shoot and root, chlorophyll, nitrogen, and phosphorus contents of chilli seedlings was found, which reveals its ability to improve the growth of crop plants. Hence, this study suggests the possibility of biosurfactant producing endophytic fungi X. regalis as a source of novel green biosurfactant for sustainable agriculture to achieve growing demands.

Immune regulation and CNS autoimmune disease

DEFF Research Database (Denmark)

Antel, J P; Owens, T

1999-01-01

The central nervous system is a demonstrated target of both clinical and experimental immune mediated disorders. Immune regulatory mechanisms operative at the levels of the systemic immune system, the blood brain barrier, and within the CNS parenchyma are important determinants of the intensity...... and duration of the tissue directed injury. Convergence of research, involving direct manipulation of specific cells and molecular mediators in animal models and in vitro analysis of human immune and neural cells and tissues, is providing increasing insight into the role of these immune regulatory functions...

Resonance in a Cone-Topped Tube

Directory of Open Access Journals (Sweden)

Angus Cheng-Huan Chia

2011-06-01

Full Text Available The relationship between ratio of the upper opening diameter of a cone-topped cylinder to the cylinder diameter,and the ratio of the length of the air column to resonant period was examined. Plastic cones with upper openings ranging from 1.3 cm to 3.6 cm and tuning forks with frequencies ranging from 261.6 Hz to 523.3 Hz were used. The transition from a standing wave in a cylindrical column to a Helmholtz-type resonance in a resonant cavity with a narrow opening was observed.

Dysflective cones: Visual function and cone reflectivity in long-term follow-up of acute bilateral foveolitis

Directory of Open Access Journals (Sweden)

Joanna H. Tu

2017-09-01

Conclusions and importance: Fundus-referenced visual testing proved useful to identify functional cones despite apparent photoreceptor loss identified using AOSLO and SD-OCT. While AOSLO and SD-OCT appear to be sensitive for the detection of abnormal or absent photoreceptors, changes in photoreceptors that are identified with these imaging tools do not correlate completely with visual function in every patient. Fundus-referenced vision testing is a useful tool to indicate the presence of cones that may be amenable to recovery or response to experimental therapies despite not being visible on confocal AOSLO or SD-OCT images.

Noninvasive gene delivery to foveal cones for vision restoration

Science.gov (United States)

Khabou, Hanen; Garita-Hernandez, Marcela; Jaillard, Céline; Brazhnikova, Elena; Bertin, Stéphane; Forster, Valérie; Desrosiers, Mélissa; Winckler, Céline; Goureau, Olivier; Duebel, Jens; Sahel, José-Alain

2018-01-01

Intraocular injection of adeno-associated viral (AAV) vectors has been an evident route for delivering gene drugs into the retina. However, gaps in our understanding of AAV transduction patterns within the anatomically unique environments of the subretinal and intravitreal space of the primate eye impeded the establishment of noninvasive and efficient gene delivery to foveal cones in the clinic. Here, we establish new vector-promoter combinations to overcome the limitations associated with AAV-mediated cone transduction in the fovea with supporting studies in mouse models, human induced pluripotent stem cell–derived organoids, postmortem human retinal explants, and living macaques. We show that an AAV9 variant provides efficient foveal cone transduction when injected into the subretinal space several millimeters away from the fovea, without detaching this delicate region. An engineered AAV2 variant provides gene delivery to foveal cones with a well-tolerated dose administered intravitreally. Both delivery modalities rely on a cone-specific promoter and result in high-level transgene expression compatible with optogenetic vision restoration. The model systems described here provide insight into the behavior of AAV vectors across species to obtain safety and efficacy needed for gene therapy in neurodegenerative disorders. PMID:29367457

Neurolymphomatosis: An International Primary CNS Lymphoma Collaborative Group report

NARCIS (Netherlands)

S. Grisariu (Sigal); B. Avni (Batia); T.T. Batchelor (Tracy); M.J. van den Bent (Martin); F. Bokstein (Felix); D. Schiff (David); O. Kuittinen (Outi); M.C. Chamberlain (Marc C.); P. Roth (Patrick); A. Nemets (Anatoly); E. Shalom (Edna); D. Ben-Yehuda (Dina); T. Siegal (Tali)

2010-01-01

textabstractNeurolymphomatosis (NL) is a rare clinical entity. The International Primary CNS Lymphoma Collaborative Group retrospectively analyzed 50 patients assembled from 12 centers in 5 countries over a 16-year period. NL was related to non-Hodgkin lymphoma in 90% and to acute leukemia in 10%.

Regulation of Adult CNS Axonal Regeneration by the Post-transcriptional Regulator Cpeb1

Directory of Open Access Journals (Sweden)

Wilson Pak-Kin Lou

2018-01-01

Full Text Available Adult mammalian central nervous system (CNS neurons are unable to regenerate following axonal injury, leading to permanent functional impairments. Yet, the reasons underlying this regeneration failure are not fully understood. Here, we studied the transcriptome and translatome shortly after spinal cord injury. Profiling of the total and ribosome-bound RNA in injured and naïve spinal cords identified a substantial post-transcriptional regulation of gene expression. In particular, transcripts associated with nervous system development were down-regulated in the total RNA fraction while remaining stably loaded onto ribosomes. Interestingly, motif association analysis of post-transcriptionally regulated transcripts identified the cytoplasmic polyadenylation element (CPE as enriched in a subset of these transcripts that was more resistant to injury-induced reduction at the transcriptome level. Modulation of these transcripts by overexpression of the CPE binding protein, Cpeb1, in mouse and Drosophila CNS neurons promoted axonal regeneration following injury. Our study uncovered a global evolutionarily conserved post-transcriptional mechanism enhancing regeneration of injured CNS axons.

Compensation of deformations in 3D cone beam tomography

International Nuclear Information System (INIS)

Desbat, L.; Roux, S.; Roux, S.; Grangeat, P.

2006-01-01

In dynamic tomography, the measured objects or organs are no-longer supposed to be static in the scanner during the acquisition but are supposed to move or to be deformed. Our approach is the analytic deformation compensation during the reconstruction. Our work concentrates on 3-dimensional cone beam tomography. We introduce a new large class of deformations preserving the 3-dimensional cone beam geometry. We show that deformations from this class can be analytically compensated. We present numerical experiments on phantoms showing the compensation of these deformations in 3-dimensional cone beam tomography. (authors)

Detail Design of the hydrogen system and the gas blanketing system for the HANARO-CNS

International Nuclear Information System (INIS)

Choi, Jung Woon; Kim, Hark Rho; Kim, Young Ki; Wu, Sang Ik; Kim, Bong Su; Lee, Yong Seop

2007-04-01

The cold neutron source (CNS), which will be installed in the vertical CN hole of the reflector tank at HANARO, makes thermal neutrons to moderate into the cold neutrons with the ranges of 0.1 ∼ 10 meV passing through a moderator at about 22K. A moderator to produce cold neutrons is liquid hydrogen, which liquefies by the heat transfer with cryogenic helium flowing from the helium refrigeration system (HRS). Because of its installed location, the hydrogen system is designed to be surrounded by the gas blanketing system to notify the leakage on the system and to prevent hydrogen leakage out of the CNS. The hydrogen system, consisted of hydrogen charging unit, hydrogen storage unit, hydrogen buffer tank, and hydrogen piping, is designed to smoothly and safely supply hydrogen to and to draw back hydrogen from the IPA of the CNS under the HRS operation mode. Described is that calculation for total required hydrogen amount in the CNS as well as operation schemes of the hydrogen system. The gas blanketing system (GBS) is designed for the supply of the compressed nitrogen gas into the air pressurized valves for the CNS, to isolate the hydrogen system from the air and the water, and to prevent air or water intrusion into the vacuum system as well as the hydrogen system. All detail descriptions are shown inhere as well as the operation scheme for the GBS

Scientific designs of pine seeds and pine cones for species conservation

Science.gov (United States)

Song, Kahye; Yeom, Eunseop; Kim, Hyejeong; Lee, Sang Joon

2015-11-01

Reproduction and propagation of species are the most important missions of every living organism. For effective species propagation, pine cones fold their scales under wet condition to prevent seeds from short-distance dispersal. They open and release their embedded seeds on dry and windy days. In this study, the micro-/macro-scale structural characteristics of pine cones and pine seeds are studied using various imaging modalities. Since the scales of pine cones consist of dead cells, the folding motion is deeply related to structural changes. The scales of pine cones consist of three layers. Among them, bract scales are only involved in collecting water. This makes pine cones reduce the amount of water and minimize the time spent on structural changes. These systems also involve in drying and recovery of pine cones. In addition, pine cones and pine seeds have advantageous structures for long-distance dispersal and response to natural disaster. Owing to these structural features, pine seeds can be released safely and efficiently, and these types of structural advantages could be mimicked for practical applications. This research was financially supported by the Creative Research Initiative of the Ministry of Science, ICT and Future Planning (MSIP) and the National Research Foundation (NRF) of Korea (Contract grant number: 2008-0061991).

CONE BIOPSY IN PREGNANCY*

African Journals Online (AJOL)

1 Mei 1971. S.-A. TYDSKRIF VIR OBSTETRIE EN GINEKOLOGIE. CONE BIOPSY ... of the abnormal cervix in pregnancy is also no longer in question following the .... the concept of cancer prophylaxis to the majority of women, many of whom ...

Measurements in a Transitioning Cone Boundary Layer at Freestream Mach 3.5

Science.gov (United States)

King, Rudolph A.; Chou, Amanda; Balakumar, Ponnampalam; Owens, Lewis R.; Kegerise, Michael A.

2016-01-01

An experimental study was conducted in the Supersonic Low-Disturbance Tunnel to investigate naturally-occurring instabilities in a supersonic boundary layer on a 7 deg half- angle cone. All tests were conducted with a nominal freestream Mach number of M(sub infinity) = 3:5, total temperature of T(sub 0) = 299:8 K, and unit Reynolds numbers of Re(sub infinity) x 10(exp -6) = 9:89, 13.85, 21.77, and 25.73 m(exp -1). Instability measurements were acquired under noisy- ow and quiet- ow conditions. Measurements were made to document the freestream and the boundary-layer edge environment, to document the cone baseline flow, and to establish the stability characteristics of the transitioning flow. Pitot pressure and hot-wire boundary- layer measurements were obtained using a model-integrated traverse system. All hot- wire results were single-point measurements and were acquired with a sensor calibrated to mass ux. For the noisy-flow conditions, excellent agreement for the growth rates and mode shapes was achieved between the measured results and linear stability theory (LST). The corresponding N factor at transition from LST is N 3:9. The stability measurements for the quiet-flow conditions were limited to the aft end of the cone. The most unstable first-mode instabilities as predicted by LST were successfully measured, but this unstable first mode was not the dominant instability measured in the boundary layer. Instead, the dominant instabilities were found to be the less-amplified, low-frequency disturbances predicted by linear stability theory, and these instabilities grew according to linear theory. These low-frequency unstable disturbances were initiated by freestream acoustic disturbances through a receptivity process that is believed to occur near the branch I locations of the cone. Under quiet-flow conditions, the boundary layer remained laminar up to the last measurement station for the largest Re1, implying a transition N factor of N greater than 8:5.

Comparison of Asymmetric and Ice-cream Cone Models for Halo Coronal Mass Ejections

Science.gov (United States)

Na, H.; Moon, Y.

2011-12-01

Halo coronal mass ejections (HCMEs) are major cause of the geomagnetic storms. To minimize the projection effect by coronagraph observation, several cone models have been suggested: an ice-cream cone model, an asymmetric cone model etc. These models allow us to determine the three dimensional parameters of HCMEs such as radial speed, angular width, and the angle between sky plane and central axis of the cone. In this study, we compare these parameters obtained from different models using 48 well-observed HCMEs from 2001 to 2002. And we obtain the root mean square error (RMS error) between measured projection speeds and calculated projection speeds for both cone models. As a result, we find that the radial speeds obtained from the models are well correlated with each other (R = 0.86), and the correlation coefficient of angular width is 0.6. The correlation coefficient of the angle between sky plane and central axis of the cone is 0.31, which is much smaller than expected. The reason may be due to the fact that the source locations of the asymmetric cone model are distributed near the center, while those of the ice-cream cone model are located in a wide range. The average RMS error of the asymmetric cone model (85.6km/s) is slightly smaller than that of the ice-cream cone model (87.8km/s).

Flavonoids and the CNS

DEFF Research Database (Denmark)

Jäger, Anna Katharina; Saaby, Lasse

2011-01-01

Flavonoids are present in almost all terrestrial plants, where they provide UV-protection and colour. Flavonoids have a fused ring system consisting of an aromatic ring and a benzopyran ring with a phenyl substituent. The flavonoids can be divided into several classes depending on their structure....... Flavonoids are present in food and medicinal plants and are thus consumed by humans. They are found in plants as glycosides. Before oral absorption, flavonoids undergo deglycosylation either by lactase phloridzin hydrolase or cytosolic ß-glucocidase. The absorbed aglycone is then conjugated by methylation......, sulphatation or glucuronidation. Both the aglycones and the conjugates can pass the blood-brain barrier. In the CNS several flavones bind to the benzodiazepine site on the GABA(A)-receptor resulting in sedation, anxiolytic or anti-convulsive effects. Flavonoids of several classes are inhibitors of monoamine...

Nontraumatic tibial polyethylene insert cone fracture in mobile-bearing posterior-stabilized total knee arthroplasty

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Yohei Tanikake

2016-12-01

Full Text Available A 72-year-old male patient underwent mobile-bearing posterior-stabilized total knee arthroplasty for osteoarthritis. He experienced a nontraumatic polyethylene tibial insert cone fracture 27 months after surgery. Scanning electron microscopy of the fracture surface of the tibial insert cone suggested progress of ductile breaking from the posterior toward the anterior of the cone due to repeated longitudinal bending stress, leading to fatigue breaking at the anterior side of the cone, followed by the tibial insert cone fracture at the anterior side of the cone, resulting in fracture at the base of the cone. This analysis shows the risk of tibial insert cone fracture due to longitudinal stress in mobile-bearing posterior-stabilized total knee arthroplasty in which an insert is designed to highly conform to the femoral component.

A map of taste neuron projections in the Drosophila CNS

Indian Academy of Sciences (India)

2014-07-08

Jul 8, 2014 ... information that they represent. The extensive ... physiology and behaviour in the wild type and in these mutants .... taste information is processed in the CNS. 2. ..... gene affecting the specificity of the chemosensory neurons of.

Phantom limb pain: a case of maladaptive CNS plasticity?

DEFF Research Database (Denmark)

Flor, Herta; Nikolajsen, Lone; Jensen, Troels Staehelin

2006-01-01

might be a phenomenon of the CNS that is related to plastic changes at several levels of the neuraxis and especially the cortex. Here, we discuss the evidence for putative pathophysiological mechanisms with an emphasis on central, and in particular cortical, changes. We cite both animal and human...

Stability Analysis of Hypersonic Boundary Layer over a Cone at Small Angle of Attack

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Feng Ji

2014-04-01

Full Text Available An investigation on the stability of hypersonic boundary layer over a cone at small angle of attack has been performed. After obtaining the steady base flow, linear stability theory (LST analysis has been made with local parallel assumption. The growth rates of the first mode and second mode waves at different streamwise locations and different azimuthal angles are obtained. The results show that the boundary layer stability was greatly influenced by small angles of attack. The maximum growth rate of the most unstable wave on the leeward is larger than that on the windward. Moreover, dominating second mode wave starts earlier on the leeward than that on the windward. The LST result also shows that there is a “valley” region around 120°~150° meridian in the maximum growth rates curve.

CLIPPERS among patients diagnosed with non-specific CNS neuroinflammatory diseases

DEFF Research Database (Denmark)

Kerrn-Jespersen, B M; Lindelof, M; Illes, Zsolt

2014-01-01

Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids (CLIPPERS) is an inflammatory CNS disorder characterized by 1) subacute onset of cerebellar and brainstem symptoms, 2) peripontine contrast-enhancing perivascular lesions with a "salt-and-pepper" appeara...

Some Extensions of Banach's Contraction Principle in Complete Cone Metric Spaces

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Raja P

2008-01-01

Full Text Available Abstract In this paper we consider complete cone metric spaces. We generalize some definitions such as -nonexpansive and -uniformly locally contractive functions -closure, -isometric in cone metric spaces, and certain fixed point theorems will be proved in those spaces. Among other results, we prove some interesting applications for the fixed point theorems in cone metric spaces.

Abbreviated exposure to hypoxia is sufficient to induce CNS dysmyelination, modulate spinal motor neuron composition, and impair motor development in neonatal mice.

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Jens O Watzlawik

Full Text Available Neonatal white matter injury (nWMI is an increasingly common cause of cerebral palsy that results predominantly from hypoxic injury to progenitor cells including those of the oligodendrocyte lineage. Existing mouse models of nWMI utilize prolonged periods of hypoxia during the neonatal period, require complex cross-fostering and exhibit poor growth and high mortality rates. Abnormal CNS myelin composition serves as the major explanation for persistent neuro-motor deficits. Here we developed a simplified model of nWMI with low mortality rates and improved growth without cross-fostering. Neonatal mice are exposed to low oxygen from postnatal day (P 3 to P7, which roughly corresponds to the period of human brain development between gestational weeks 32 and 36. CNS hypomyelination is detectable for 2-3 weeks post injury and strongly correlates with levels of body and brain weight loss. Immediately following hypoxia treatment, cell death was evident in multiple brain regions, most notably in superficial and deep cortical layers as well as the subventricular zone progenitor compartment. PDGFαR, Nkx2.2, and Olig2 positive oligodendrocyte progenitor cell were significantly reduced until postnatal day 27. In addition to CNS dysmyelination we identified a novel pathological marker for adult hypoxic animals that strongly correlates with life-long neuro-motor deficits. Mice reared under hypoxia reveal an abnormal spinal neuron composition with increased small and medium diameter axons and decreased large diameter axons in thoracic lateral and anterior funiculi. Differences were particularly pronounced in white matter motor tracts left and right of the anterior median fissure. Our findings suggest that 4 days of exposure to hypoxia are sufficient to induce experimental nWMI in CD1 mice, thus providing a model to test new therapeutics. Pathological hallmarks of this model include early cell death, decreased OPCs and hypomyelination in early postnatal life

Topografia do cone medular em gatos sem raça definida Topography of the medullar cone in the domestic non-defined breed cat

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P.H.C. Silva

2009-10-01

Full Text Available Estudou-se a topografia post mortem do cone medular em 30 gatos adultos sem raça definida. Procedeu-se à remoção da pele e da musculatura dorsal da coluna vertebral e expuseram-se a medula espinhal e seus envoltórios, após a secção dos arcos vertebrais. O cone medular foi evidenciado e mensurado. Avaliou-se a sua relação com as vértebras lombares (L, sacrais (S e caudais (Cd. O cone medular variou de 3,40 a 8,00cm (média=5,08cm. A esqueletopia foi variável, pois em 24 (80% animais o cone medular iniciou-se na vértebra L6; em quatro (13,3%, na L7; e em dois (6,7%, na L5. Em 12 (40% animais terminou na vértebra S2; em 10 (33,3%, na S3; em cinco (16,7%, na Cd1; em dois (6,7%, na S1; e em um (3,3% na Cd2.It was studied the post mortem topography of the medullar cone in 30 adult non-defined breed cats. The dorsal skin and muscles from the vertebral column were removed and the spinal cord and its wrappers were visualized, after the section of the vertebral arcs. The medullar cone was then exposed and measured. Its relationship with lumbar (L, sacral (S, and caudal (Cd vertebrae was determined. The length of the medullar cone presented a variation from 3.40 to 8.00cm (average 5.08cm. Its skeletopy was variable; since in 24 animals (80%, the medullar cone began at the L6 vertebra; in four (13.3%, at the L7; and in two (6.7% at the L5 vertebra. It ended in 12 (40% animals at the S2 vertebra; in 10 (33,33%, at the S3; in five (16.7% at the caudal (Cd vertebra; in two (6.7%, at the S1; and in one (3.3%, at the Cd2.

Effect of loss cone on confinement in toroidal helical device

International Nuclear Information System (INIS)

Itoh, K.; Itoh, S.-I.; Fukuyama, A.; Hanatani, K.

1988-12-01

Analytical estimation is given on the loss cone in the toroidal helical devices in the presence of the radial electric field and the modulation of the helical ripple. The minimum energy of particles entering the loss cone is calculated. The modulation is not always effective in reducing the loss in the presence of the radial electric field. The plasma loss due to the loss cone is estimated in the collisionless limit. The radial electric field is estimated in the presence of the loss cone. It is found that the transition to the solution with positive radial electric field, which is necessary to achieve the high-ion-temperature mode, becomes difficult. This difficulty is large for the systems with the small helical ripple. (author)

Response of Spectral Reflectances and Vegetation Indices on Varying Juniper Cone Densities

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Guillermo E. Ponce-Campos

2013-10-01

Full Text Available Juniper trees are widely distributed throughout the world and are common sources of allergies when microscopic pollen grains are transported by wind and inhaled. In this study, we investigated the spectral influences of pollen-discharging male juniper cones within a juniper canopy. This was done through a controlled outdoor experiment involving ASD FieldSpec Pro Spectroradiometer measurements over juniper canopies of varying cone densities. Broadband and narrowband spectral reflectance and vegetation index (VI patterns were evaluated as to their sensitivity and their ability to discriminate the presence of cones. The overall aim of this research was to assess remotely sensed phenological capabilities to detect pollen-bearing juniper trees for public health applications. A general decrease in reflectance values with increasing juniper cone density was found, particularly in the Green (545–565 nm and NIR (750–1,350 nm regions. In contrast, reflectances in the shortwave-infrared (SWIR, 2,000 nm to 2,350 nm region decreased from no cone presence to intermediate amounts (90 g/m2 and then increased from intermediate levels to the highest cone densities (200 g/m2. Reflectance patterns in the Red (620–700 nm were more complex due to shifting contrast patterns in absorptance between cones and juniper foliage, where juniper foliage is more absorbing than cones only within the intense narrowband region of maximum chlorophyll absorption near 680 nm. Overall, narrowband reflectances were more sensitive to cone density changes than the equivalent MODIS broadbands. In all VIs analyzed, there were significant relationships with cone density levels, particularly with the narrowband versions and the two-band vegetation index (TBVI based on Green and Red bands, a promising outcome for the use of phenocams in juniper phenology trait studies. These results indicate that spectral indices are sensitive to certain juniper phenologic traits that can potentially be

Pollen cone anatomy of Classostrobus crossii sp. nov. (Cheirolepidiaceae)

Energy Technology Data Exchange (ETDEWEB)

Rothwell, Gar W.; Mapes, Gene [Department of Environmental and Plant Biology, Ohio University, Athens OH 45701 (United States); Hilton, Jason [Department of Earth Sciences, School of Geography, Earth and Environmental Sciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Hollingworth, Neville T. [Centre for Ecology and Hydrology, Winfrith Technology Centre, Winfrith Newburgh, Dorchester, Dorset, DT2 8ZD (United Kingdom)

2007-01-02

Discovery of a permineralized fossil cone in Mesozoic deposits of southern England provides an opportunity to document the first detailed evidence of internal pollen cone anatomy for the extinct conifer family Cheirolepidiaceae. The specimen, described here as Classostrobus crossii sp. nov., occurs in a calcareous nodule recovered from Middle Jurassic marine sediments of the Lower Callovian Sigaloceras calloviense biozone, Kellaways, near Cirencester, England. The cone is 2.0 cm long and 1.8 cm wide. Sporophylls diverge helically from the axis. Each sporophyll displays a narrow stalk and a distal lamina approx. 11 mm long that tapers to a pointed tip. There is also a basal keel that bends inward at the bottom and sides to form a shallow pocket. A single vascular bundle diverges from the cone axis, extends distally into the sporophyll stalk at the contact of two distinctly different histological zones, and further expands into the distal lamina as transfusion tracheids. Several pollen sacs are attached abaxially at the juncture of the sporophyll stalk and keel. Pollen is roughly spheroidal, 26-35 {mu}m in diameter, with unequal polar caps separated by a striated belt with a subequatorial furrow. This specimen helps clarify the range of variation in the morphology of Mesozoic conifer pollen cones. (author)

Comparison of three-dimensional parameters of Halo CMEs using three cone models

Science.gov (United States)

Na, H.; Moon, Y.; Jang, S.; Lee, K.

2012-12-01

Halo coronal mass ejections (HCMEs) are a major cause of geomagnetic storms and their three dimensional structures are important for space weather. In this study, we compare three cone models: an elliptical cone model, an ice-cream cone model, and an asymmetric cone model. These models allow us to determine the three dimensional parameters of HCMEs such as radial speed, angular width, and the angle (γ) between sky plane and cone axis. We compare these parameters obtained from three models using 62 well-observed HCMEs observed by SOHO/LASCO from 2001 to 2002. Then we obtain the root mean square error (RMS error) between maximum measured projection speeds and their calculated projection speeds from the cone models. As a result, we find that the radial speeds obtained from the models are well correlated with one another (R > 0.84). The correlation coefficients between angular widths are ranges from 0.04 to 0.53 and those between γ values are from -0.15 to 0.47, which are much smaller than expected. The reason may be due to different assumptions and methods. The RMS errors between the maximum measured projection speeds and the maximum estimated projection speeds of the elliptical cone model, the ice-cream cone model, and the asymmetric cone model are 213 km/s, 254 km/s, and 267 km/s, respectively. And we obtain the correlation coefficients between the location from the models and the flare location (R > 0.75). Finally, we discuss strengths and weaknesses of these models in terms of space weather application.

Inflammatory cytokines in the brain: does the CNS shape immune responses?

Science.gov (United States)

Owens, T; Renno, T; Taupin, V; Krakowski, M

1994-12-01

Immune responses in the central nervous system (CNS) have traditionally been regarded as representing the intrusion of an unruly, ill-behaved mob of leukocytes into the well-ordered and organized domain of thought and reason. However, results accumulated over the past few years suggest that, far from being an immunologically privileged organ, T lymphocytes may be regular and frequent visitors to the CNS, for purposes of immune surveillance. Here, Trevor Owens and colleagues propose that the brain itself can regulate or shape immune responses therein. Furthermore, given that the immune cells may be subverted to autoimmunity, they suggest that the study of inflammatory autoimmune disease in the brain may shed light on the ability of the local environment to regulate immune responses.

Predation and protection in the macroevolutionary history of conifer cones

Science.gov (United States)

Leslie, Andrew B.

2011-01-01

Conifers are an excellent group in which to explore how changing ecological interactions may have influenced the allocation of reproductive tissues in seed plants over long time scales, because of their extensive fossil record and their important role in terrestrial ecosystems since the Palaeozoic. Measurements of individual conifer pollen-producing and seed-producing cones from the Pennsylvanian to the Recent show that the relative amount of tissue invested in pollen cones has remained constant through time, while seed cones show a sharp increase in proportional tissue investment in the Jurassic that has continued to intensify to the present day. Since seed size in conifers has remained similar through time, this increase reflects greater investment in protective cone tissues such as robust, tightly packed scales. This shift in morphology and tissue allocation is broadly concurrent with the appearance of new vertebrate groups capable of browsing in tree canopies, as well as a diversification of insect-feeding strategies, suggesting that an important change in plant–animal interactions occurred over the Mesozoic that favoured an increase in seed cone protective tissues. PMID:21345864

Numerical Investigation of Double-Cone Flows with High Enthalpy Effects

Science.gov (United States)

Nompelis, I.; Candler, G. V.

2009-01-01

A numerical study of shock/shock and shock/boundary layer interactions generated by a double-cone model that is placed in a hypersonic free-stream is presented. Computational results are compared with the experimental measurements made at the CUBRC LENS facility for nitrogen flows at high enthalpy conditions. The CFD predictions agree well with surface pressure and heat-flux measurements for all but one of the double-cone cases that have been studied by the authors. Unsteadiness is observed in computations of one of the LENS cases, however for this case the experimental measurements show that the flowfield is steady. To understand this discrepancy, several double-cone experiments performed in two different facilities with both air and nitrogen as the working gas are examined in the present study. Computational results agree well with measurements made in both the AEDC tunnel 9 and the CUBRC LENS facility for double-cone flows at low free-stream Reynolds numbers where the flow is steady. It is shown that at higher free- stream pressures the double-cone simulations develop instabilities that result in an unsteady separation.

Malignant lymphoma in central nervous system (CNS)

International Nuclear Information System (INIS)

Fujiyoshi, Kenji; Fukuyama, Hidenao; Akiguchi, Ichiro; Kameyama, Masakuni; Nishimura, Toshio.

1984-01-01

A 71-year-old male was admitted to Kohka Public Hospital on January 4, 1980, because of frequent vomiting and recent memory loss. Two weeks before admission upper G-I series showed no abnormalities. Physical and neurological examinations revealed no abnormalities except for slightly apathetic appearance and recent memory loss. Mild pleocytosis and marked increase of protein in CSF were observed. CT scan on January 17 showed high density areas in both medial sides of temporal lobes with remarkable contrast enhancement. His memory and, consciousness disturbances gradually aggravated, accompanied by abnormal density spreading around the ventricle walls like ventriculitis. He was transfered to Kyoto University Hospital on March 17, and malignant lymphoma was diagnosed on the basis of CSF cytology. Radiation and chemotherapy alleviated the CNS involvement and he regained normal mental function. On June 16, he developed pneumonia followed by status epilepticus. Autopsy findings revealed no lymphoid cell infiltration, but fibrous tissues in both hippocampal gyri and lymphomatous cells in the liver, which could not be suspected on clinical examinations. Apparent malignant lymphoma cells were not found in lymph nodes. This case indicated peculiar evolution of malignant lymphoma from liver to CNS or vice versa. We could not decide which organ was primary. CT findings of this case was very interesting; they resembled ventriculitis, which simulate tumors such as medulloblastoma or ependymoma spreading under ependymal lining. (author)

A Novel Robust H∞ Filter Based on Krein Space Theory in the SINS/CNS Attitude Reference System

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Fei Yu

2016-03-01

Full Text Available Owing to their numerous merits, such as compact, autonomous and independence, the strapdown inertial navigation system (SINS and celestial navigation system (CNS can be used in marine applications. What is more, due to the complementary navigation information obtained from two different kinds of sensors, the accuracy of the SINS/CNS integrated navigation system can be enhanced availably. Thus, the SINS/CNS system is widely used in the marine navigation field. However, the CNS is easily interfered with by the surroundings, which will lead to the output being discontinuous. Thus, the uncertainty problem caused by the lost measurement will reduce the system accuracy. In this paper, a robust H∞ filter based on the Krein space theory is proposed. The Krein space theory is introduced firstly, and then, the linear state and observation models of the SINS/CNS integrated navigation system are established reasonably. By taking the uncertainty problem into account, in this paper, a new robust H∞ filter is proposed to improve the robustness of the integrated system. At last, this new robust filter based on the Krein space theory is estimated by numerical simulations and actual experiments. Additionally, the simulation and experiment results and analysis show that the attitude errors can be reduced by utilizing the proposed robust filter effectively when the measurements are missing discontinuous. Compared to the traditional Kalman filter (KF method, the accuracy of the SINS/CNS integrated system is improved, verifying the robustness and the availability of the proposed robust H∞ filter.

Meaning of visualizing retinal cone mosaic on adaptive optics images.

Science.gov (United States)

Jacob, Julie; Paques, Michel; Krivosic, Valérie; Dupas, Bénédicte; Couturier, Aude; Kulcsar, Caroline; Tadayoni, Ramin; Massin, Pascale; Gaudric, Alain

2015-01-01

To explore the anatomic correlation of the retinal cone mosaic on adaptive optics images. Retrospective nonconsecutive observational case series. A retrospective review of the multimodal imaging charts of 6 patients with focal alteration of the cone mosaic on adaptive optics was performed. Retinal diseases included acute posterior multifocal placoid pigment epitheliopathy (n = 1), hydroxychloroquine retinopathy (n = 1), and macular telangiectasia type 2 (n = 4). High-resolution retinal images were obtained using a flood-illumination adaptive optics camera. Images were recorded using standard imaging modalities: color and red-free fundus camera photography; infrared reflectance scanning laser ophthalmoscopy, fluorescein angiography, indocyanine green angiography, and spectral-domain optical coherence tomography (OCT) images. On OCT, in the marginal zone of the lesions, a disappearance of the interdigitation zone was observed, while the ellipsoid zone was preserved. Image recording demonstrated that such attenuation of the interdigitation zone co-localized with the disappearance of the cone mosaic on adaptive optics images. In 1 case, the restoration of the interdigitation zone paralleled that of the cone mosaic after a 2-month follow-up. Our results suggest that the interdigitation zone could contribute substantially to the reflectance of the cone photoreceptor mosaic. The absence of cones on adaptive optics images does not necessarily mean photoreceptor cell death. Copyright © 2015 Elsevier Inc. All rights reserved.

Polynomial Primal-Dual Cone Affine Scaling for Semidefinite Programming

NARCIS (Netherlands)

A.B. Berkelaar (Arjan); J.F. Sturm; S. Zhang (Shuzhong)

1996-01-01

textabstractIn this paper we generalize the primal--dual cone affine scaling algorithm of Sturm and Zhang to semidefinite programming. We show in this paper that the underlying ideas of the cone affine scaling algorithm can be naturely applied to semidefinite programming, resulting in a new

Axial length and cone density as assessed with adaptive optics in myopia

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Supriya Dabir

2015-01-01

Full Text Available Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL. Subjects and Methods: Twenty-five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM. Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455-16,404 ± 4494/mm 2 respectively. There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.

Performance of the coned-face end seal with regard to energy conservation

Science.gov (United States)

Sehnal, J.; Sedy, J.; Zobens, A.; Etsion, I.

1982-01-01

The effects of face coning on seal performance are evaluated with particular regard to the energy saving potential of convex conedface end seals as indicated by torque reduction. Experiments were conducted using a conventional carbon flat-face pusher-type seal, a coned-face pusher-type seal, coned-face bellows-type seal, and a modified coned-face pusher-type seal intended for dynamically unstable operation, with shaft rotation at up to 8000 rpm, pressures of up to 2758 kPa, and a petroleum-based turbine oil as lubricant. Torque at the seal interface is found to be reduced by 42% when the standard flat-face seal is replaced by a coned seal, although the leakage of the cone-face seal was 11 times greater. Reduction of seal balance from 76.1 to 51.3% resulted in an additional 44% reduction in torque, although at the expense of excessive leakage, but did not produce unstable operation. Face temperatures were reduced by 33-56 C and wear was also reduced greatly on the cone face seals. Seal performance is noted to be in agreement with analytical calculations.

Maternal stress, nutrition and physical activity: Impact on immune function, CNS development and psychopathology.

Science.gov (United States)

Marques, Andrea Horvath; Bjørke-Monsen, Anne-Lise; Teixeira, Antônio L; Silverman, Marni N

2015-08-18

Evidence suggests that maternal and fetal immune dysfunction may impact fetal brain development and could play a role in neurodevelopmental disorders, although the definitive pathophysiological mechanisms are still not completely understood. Stress, malnutrition and physical inactivity are three maternal behavioral lifestyle factors that can influence immune and central nervous system (CNS) functions in both the mother and fetus, and may therefore, increase risk for neurodevelopmental/psychiatric disorders. First, we will briefly review some aspects of maternal-fetal immune system interactions and development of immune tolerance. Second, we will discuss the bidirectional communication between the immune system and CNS and the pathways by which immune dysfunction could contribute to neurodevelopmental disorders. Third, we will discuss the effects of prenatal stress and malnutrition (over and undernutrition) on perinatal programming of the CNS and immune system, and how this might influence neurodevelopment. Finally, we will discuss the beneficial impact of physical fitness during pregnancy on the maternal-fetal unit and infant and how regular physical activity and exercise can be an effective buffer against stress- and inflammatory-related disorders. Although regular physical activity has been shown to promote neuroplasticity and an anti-inflammatory state in the adult, there is a paucity of studies evaluating its impact on CNS and immune function during pregnancy. Implementing stress reduction, proper nutrition and ample physical activity during pregnancy and the childbearing period may be an efficient strategy to counteract the impact of maternal stress and malnutrition/obesity on the developing fetus. Such behavioral interventions could have an impact on early development of the CNS and immune system and contribute to the prevention of neurodevelopmental and psychiatric disorders. Further research is needed to elucidate this relationship and the underlying

SPARC and GluA1-Containing AMPA Receptors Promote Neuronal Health Following CNS Injury

Directory of Open Access Journals (Sweden)

Emma V. Jones

2018-02-01

Full Text Available The proper formation and maintenance of functional synapses in the central nervous system (CNS requires communication between neurons and astrocytes and the ability of astrocytes to release neuromodulatory molecules. Previously, we described a novel role for the astrocyte-secreted matricellular protein SPARC (Secreted Protein, Acidic and Rich in Cysteine in regulating α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs and plasticity at developing synapses. SPARC is highly expressed by astrocytes and microglia during CNS development but its level is reduced in adulthood. Interestingly, SPARC has been shown to be upregulated in CNS injury and disease. However, the role of SPARC upregulation in these contexts is not fully understood. In this study, we investigated the effect of chronic SPARC administration on glutamate receptors on mature hippocampal neuron cultures and following CNS injury. We found that SPARC treatment increased the number of GluA1-containing AMPARs at synapses and enhanced synaptic function. Furthermore, we determined that the increase in synaptic strength induced by SPARC could be inhibited by Philanthotoxin-433, a blocker of homomeric GluA1-containing AMPARs. We then investigated the effect of SPARC treatment on neuronal health in an injury context where SPARC expression is upregulated. We found that SPARC levels are increased in astrocytes and microglia following middle cerebral artery occlusion (MCAO in vivo and oxygen-glucose deprivation (OGD in vitro. Remarkably, chronic pre-treatment with SPARC prevented OGD-induced loss of synaptic GluA1. Furthermore, SPARC treatment reduced neuronal death through Philanthotoxin-433 sensitive GluA1 receptors. Taken together, this study suggests a novel role for SPARC and GluA1 in promoting neuronal health and recovery following CNS damage.

Shape measurement and vibration analysis of moving speaker cone

Science.gov (United States)

Zhang, Qican; Liu, Yuankun; Lehtonen, Petri

2014-06-01

Surface three-dimensional (3-D) shape information is needed for many fast processes such as structural testing of material, standing waves on loudspeaker cone, etc. Usually measurement is done from limited number of points using electrical sensors or laser distance meters. Fourier Transform Profilometry (FTP) enables fast shape measurement of the whole surface. Method is based on angled sinusoidal fringe pattern projection and image capturing. FTP requires only one image of the deformed fringe pattern to restore the 3-D shape of the measured object, which makes real-time or dynamic data processing possible. In our experiment the method was used for loudspeaker cone distortion measurement in dynamic conditions. For sound quality issues it is important that the whole cone moves in same phase and there are no partial waves. Our imaging resolution was 1280x1024 pixels and frame rate was 200 fps. Using our setup we found unwanted spatial waves in our sample cone.

Visible and Near-Infrared Spectroscopy of Hephaestus Fossae Cratered Cones, Mars

Science.gov (United States)

Dapremont, A.; Wray, J. J.

2017-12-01

Hephaestus Fossae are a system of sub-parallel fractures on Mars (> 500 km long) interpreted as near-surface tensional cracks [1]. Images of the Martian surface from the High Resolution Imaging Science Experiment have revealed cratered cones within the Hephaestus Fossae region. A volcanic origin (cinder/tuff cones) has been proposed for these features based on morphometric measurements and fine-scale surface characteristics [2]. In an effort to further constrain the origin of these cones as the products of igneous or sedimentary volcanism, we use data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). We take advantage of CRISM's S (0.4 - 1.0 microns) and L (1.0 - 3.9 microns) detector wavelength ranges to investigate the presence or absence of spectral signatures consistent with previous identifications of igneous and mud volcanism products on Mars [3,4]. Hephaestus Fossae cratered cone rims exhibit a consistent nanophase ferric oxide signature. We also identify ferrous phases and 3-micron absorptions (attributed to fundamental vibrational stretch frequencies in H2O) on the crater rims of several cones. Mafic signatures on cratered cone rims support an igneous provenance for these features. The 3-micron absorptions are consistent with the presence of structurally bound or adsorbed water. Our CRISM observations are similar to those of small edifice features in Chryse Planitia, which were interpreted as mud volcanism products based on their enrichment of nanophase ferric minerals and 3-micron absorptions on summit crater rims [3]. Hydrothermal activity was invoked for a Coprates Chasma pitted cone (scoria/tuff cone) based on CRISM identification of partially dehydrated opaline silica, which we do not observe in Hephaestus Fossae [4]. Our spectral observations are more consistent with mud volcanism, but we do not definitively rule out an igneous volcanic origin for the cones in our study region. We demonstrate that VNIR spectroscopy is a valuable

Nogo-A is a reliable oligodendroglial marker in adult human and mouse CNS and in demyelinated lesions

DEFF Research Database (Denmark)

Kuhlmann, Tanja; Remington, Leah; Maruschak, Brigitte

2007-01-01

to be strongly expressed in mature oligodendrocytes in vivo. In the present investigation we analyzed the expression patterns of Nogo-A in adult mouse and human CNS as well as in demyelinating animal models and multiple sclerosis lesions. Nogo-A expression was compared with that of other frequently used...... oligodendroglial markers such as CC1, CNP, and in situ hybridization for proteolipid protein mRNA. Nogo-A strongly and reliably labeled oligodendrocytes in the adult CNS as well as in demyelinating lesions and thus represents a valuable tool for the identification of oligodendrocytes in human and mouse CNS tissue...

Ablation and cone formation mechanism on CR-39 by ArF laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Shakeri Jooybari, B., E-mail: baninshakery@gmail.com, E-mail: hafarideh@aut.ac.ir [Department of Energy Engineering and Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Nuclear Science and Technology Research Institute NSRT, Tehran (Iran, Islamic Republic of); Afarideh, H., E-mail: baninshakery@gmail.com, E-mail: hafarideh@aut.ac.ir [Department of Energy Engineering and Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Lamehi-Rachti, M. [Nuclear Science and Technology Research Institute NSRT, Tehran (Iran, Islamic Republic of); Ghergherehchi, M. [Department of Energy Engineering and Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); College of Information and Communication Engineering, Sungkyunkwan University, Suwon (Korea, Republic of)

2015-03-07

In this work, chemical properties, surface modification, and micro structures formation on ablated polyallyl di-glycol carbonate (CR-39) polymer by ArF laser irradiation (λ = 193 nm) at various fluences and pulse number were investigated. CR-39 samples have been irradiated with an ArF laser (193 nm) at a repetition rate of 1 Hz. Threshold fluence of ablation and effective absorption coefficient of CR-39 were determined. Conical microstructures (Taylor cone) formed on laser-ablated CR-39 exhibit: smooth, Taylor cone shape walls and sharp tips together with interference and well defined fringe-structure with a period of 230 nm, around cone base. Mechanism of cone formation and cone evolution of CR-39 ablated surface were investigated by change of fluences (at a given pulse number) and pulse number (at a given fluence). Cone height, cone base, and region of interface were increased in micrometer steps by increasing the total fluence. Depression on the base of the cone and the circular fringe were simulated. FTIR spectra were measured and energy dispersive x-ray analysis of irradiated and un-irradiated samples was performed.

On the geometry of null cones to infinity under curvature flux bounds

International Nuclear Information System (INIS)

Alexakis, Spyros; Shao, Arick

2014-01-01

The main objective of this paper is to control the geometry of a future outgoing truncated null cone extending smoothly toward infinity in an Einstein-vacuum spacetime. In particular, we wish to do this under minimal regularity assumptions, namely, at the (weighted) L 2 -curvature level. We show that if the curvature flux and the data on an initial sphere of the cone are sufficiently close to the corresponding values in a standard Minkowski or Schwarzschild null cone, then we can obtain quantitative bounds on the geometry of the entire infinite cone. The same bounds also imply the existence of limits at infinity, along the null cone, of naturally scaled geometric quantities. In Alexakis and Shao (2013 Bounds on the Bondi energy by a flux of curvature arXiv:1308.4170), we will apply these results in order to control various physical quantities—e.g., the Bondi energy and (linear and angular) momenta—associated with such infinite null cones in vacuum spacetimes. (paper)

Buckling behaviour of imperfect ring-stiffened cone-cylinder intersections under internal pressure

International Nuclear Information System (INIS)

Zhao, Y.

2005-01-01

Cone-cylinder intersections are used commonly in pressure vessels and piping. In the case of a cone large end-to-cylinder intersection under internal pressure, the intersection is subject to a large circumferential compressive force. While both the cone and the cylinder may be locally thickened to strengthen the intersection, it is often desirable and convenient to provide an annular plate ring at the cone-to-cylinder joint to supplement local thickening or as an alternative strengthening measure, leading to a ring-stiffened cone-cylinder intersection. Only limited work has been carried out specifically on ring-stiffened cone-cylinder intersections under internal pressure. This paper presents the first experimental study on such intersections. In addition to the presentation of test results including geometric imperfections, failure behaviour and the determination of buckling mode and load based on displacement measurements, results from nonlinear bifurcation analysis using the perfect shape and nonlinear analysis using the measured imperfect shape are presented and compared with the experimental results

Comparative analysis of acid sphingomyelinase distribution in the CNS of rats and mice following intracerebroventricular delivery.

Directory of Open Access Journals (Sweden)

Christopher M Treleaven

Full Text Available Niemann-Pick A (NPA disease is a lysosomal storage disorder (LSD caused by a deficiency in acid sphingomyelinase (ASM activity. Previously, we reported that biochemical and functional abnormalities observed in ASM knockout (ASMKO mice could be partially alleviated by intracerebroventricular (ICV infusion of hASM. We now show that this route of delivery also results in widespread enzyme distribution throughout the rat brain and spinal cord. However, enzyme diffusion into CNS parenchyma did not occur in a linear dose-dependent fashion. Moreover, although the levels of hASM detected in the rat CNS were determined to be within the range shown to be therapeutic in ASMKO mice, the absolute amounts represented less than 1% of the total dose administered. Finally, our results also showed that similar levels of enzyme distribution are achieved across rodent species when the dose is normalized to CNS weight as opposed to whole body weight. Collectively, these data suggest that the efficacy observed following ICV delivery of hASM in ASMKO mice could be scaled to CNS of the rat.

Eruptive and Geomorphic Processes at the Lathrop Wells Scoria Cone

International Nuclear Information System (INIS)

G. Valentine; D.J. Krier; F.V. Perry; G. Heiken

2006-01-01

The ∼80 ka Lathrop Wells volcano (southern Nevada, U.S.A.) preserves evidence for a range of explosive processes and emplacement mechanisms of pyroclastic deposits and lava fields in a small-volume basaltic center. Early cone building by Strombolian bursts was accompanied by development of a fan-like lava field reaching ∼800 m distance from the cone, built upon a gently sloping surface. Lava flows carried rafts of cone deposits, which provide indirect evidence for cone facies in lieu of direct exposures in the active quarry. Subsequent activity was of a violent Strombolian nature, with many episodes of sustained eruption columns up to a few km in height. These deposited layers of scoria lapilli and ash in different directions depending upon wind direction at the time of a given episode, reaching up to ∼20 km from the vent, and also produced the bulk of the scoria cone. Lava effusion migrated from south to north around the eastern base of the cone as accumulation of lavas successively reversed the topography at the base of the cone. Late lavas were emplaced during violent Strombolian activity and continued for some time after explosive eruptions had waned. Volumes of the eruptive products are: fallout--0.07 km 3 , scoria cone--0.02 km 3 , and lavas--0.03 km 3 . Shallow-derived xenolith concentrations suggest an upper bound on average conduit diameter of ∼21 m in the uppermost 335 m beneath the volcano. The volcano was constructed over a period of at least seven months with cone building occurring only during part of that time, based upon analogy with historical eruptions. Post-eruptive geomorphic evolution varied for the three main surface types that were produced by volcanic activity: (1) scoria cone, (2) low relief surfaces (including lavas) with abundant pyroclastic material, and (3) lavas with little pyroclastic material. The role of these different initial textures must be accounted for in estimating relative ages of volcanic surfaces, and failure to

Eruptive and Geomorphic Processes at the Lathrop Wells Scoria Cone

Energy Technology Data Exchange (ETDEWEB)

G. Valentine; D.J. Krier; F.V. Perry; G. Heiken

2006-08-03

The {approx}80 ka Lathrop Wells volcano (southern Nevada, U.S.A.) preserves evidence for a range of explosive processes and emplacement mechanisms of pyroclastic deposits and lava fields in a small-volume basaltic center. Early cone building by Strombolian bursts was accompanied by development of a fan-like lava field reaching {approx}800 m distance from the cone, built upon a gently sloping surface. Lava flows carried rafts of cone deposits, which provide indirect evidence for cone facies in lieu of direct exposures in the active quarry. Subsequent activity was of a violent Strombolian nature, with many episodes of sustained eruption columns up to a few km in height. These deposited layers of scoria lapilli and ash in different directions depending upon wind direction at the time of a given episode, reaching up to {approx}20 km from the vent, and also produced the bulk of the scoria cone. Lava effusion migrated from south to north around the eastern base of the cone as accumulation of lavas successively reversed the topography at the base of the cone. Late lavas were emplaced during violent Strombolian activity and continued for some time after explosive eruptions had waned. Volumes of the eruptive products are: fallout--0.07 km{sup 3}, scoria cone--0.02 km{sup 3}, and lavas--0.03 km{sup 3}. Shallow-derived xenolith concentrations suggest an upper bound on average conduit diameter of {approx}21 m in the uppermost 335 m beneath the volcano. The volcano was constructed over a period of at least seven months with cone building occurring only during part of that time, based upon analogy with historical eruptions. Post-eruptive geomorphic evolution varied for the three main surface types that were produced by volcanic activity: (1) scoria cone, (2) low relief surfaces (including lavas) with abundant pyroclastic material, and (3) lavas with little pyroclastic material. The role of these different initial textures must be accounted for in estimating relative ages of

Topological Vector Space-Valued Cone Metric Spaces and Fixed Point Theorems

Directory of Open Access Journals (Sweden)

Radenović Stojan

2010-01-01

Full Text Available We develop the theory of topological vector space valued cone metric spaces with nonnormal cones. We prove three general fixed point results in these spaces and deduce as corollaries several extensions of theorems about fixed points and common fixed points, known from the theory of (normed-valued cone metric spaces. Examples are given to distinguish our results from the known ones.

Tendencies the treatment of the central nervous system (CNS) tumors

International Nuclear Information System (INIS)

Alert Silva, Jose; Jimenez Medina, Jose

2004-01-01

It is known that the treatment of the central nervous system (CNS) tumors is based on the use of surgery and radiotherapy (RT) and that chemotherapy (QMT) is used even more, as well as the other drugs. A bibliographic review was made to update the knowledge on the current trends and perspectives of RT applied to CNS tumors. The following were found among them: a) combinations of RT and CMT; b) radiosensitizers incorporated to the radiant treatment; c) angiogenesis inhibitors associated with RT; d) the scale-up or increase of the RT doses thanks to the development of new technologies, such as 3 D conformal radiotherapy, intensity- modulated radiotherapy, surgery and others. Another field of research is that of the changes in the rhythm or fractioning of the RT: hyperfractionated, accelerated, combinations of both, etc., which will allow mainly to increase the dosage scale-up

Commercial viability of CNS drugs: balancing the risk/reward profile.

Science.gov (United States)

Johnson, Ginger S

2014-01-01

CNS has historically been a formidable therapeutic area in which to innovate owing to biological (e.g., complex neurobiology, difficulty reaching the target), as well as clinical (e.g., subjective clinical endpoints, high placebo response, lack of biomarkers) challenges. In the current market where many of the larger diseases are dominated by a generic standard of care, commercial challenges now make the triple threat of scientific-clinical-commercial risk too much for many players to tackle. However, opportunities do exist for smaller biotech companies to concentrate on narrowly focused patient populations associated with high unmet need for which risk can be tightly defined. In CNS, there are two major areas to balance the risk/reward profile and create commercially viable opportunities: To realize value, all companies (start-ups and big players) must define, measure and quantify clear and meaningful value to all stakeholders: physicians, patients, caregivers and payers. © 2013.

A Clinical Evaluation Of Cone Beam Computed Tomography

Science.gov (United States)

2016-06-01

A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY by Bryan James Behm, D.D.S. Lieutenant, Dental Corps United States Navy A thesis... COMPUTED TOMOGRAPHY " is appropriately acknowledged and, beyond brief excerpts, is with the permission of the copyright owner. ~mes Behm Endodontic...printed without the expressed written permission of the author. IV ABSTRACT A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY BRYAN JAMES

Neurosurgeon as innovator: William V. Cone (1897-1959).

Science.gov (United States)

Preul, M C; Stratford, J; Bertrand, G; Feindel, W

1993-10-01

Neurosurgeons are well known for being productive researchers and innovators. Few, however, have possessed the prolific ingenuity of William Cone. In 1934, he and William Penfield were cofounders of the Montreal Neurological Institute where, until 1959, he filled the twin roles of neurosurgeon-in-chief and neuropathologist. Because he did not find writing easy, many of his technical inventions and refinements remained unpublished. His numerous innovations included the extensive use of twist-drill technique for biopsy, drainage for subdural hematoma and cerebral abscess, and ventriculography. In the mid-1940's, he developed power tools driven by nitrogen that led to the modern, universally used air-driven tool systems. He had a special interest in the treatment of spinal dysfunction, for which he invented the Cone-Barton skull-traction tongs along with the Cone spinal operating table. He also devised operative procedures for vertebral fracture-dislocation and craniospinal anomalies. For the maintenance of muscle tone in the paralyzed bladder, he constructed a tidal drainage system. He introduced and popularized ventriculoperitoneal shunting techniques and carried out some of the earliest experimental trails to treat brain infections with sulphonamide and antibiotic drugs. He designed his own set of surgical suction devices, bone rongeurs, and a personal suction "air-conditioning" system for each surgeon. He had a keen early interest in intracranial tumors, and also demonstrated on monkeys how subdural mass lesions caused pupillary dilation and mesial temporal lobe damage due to cerebral compression. His work for the military during World War II on effects of altitude on brain pressure remained classified for many years. The first clipping and excision of an intracranial aneurysm is attributed to Cone. Although Penfield was known as "the Chief," Cone was referred to as "the Boss." His fervent dedication to provide total care to his patients was expressed in round

Endovascular transplantation of stem cells to the injured rat CNS

Energy Technology Data Exchange (ETDEWEB)

Lundberg, Johan; Soederman, Mikael; Andersson, Tommy; Holmin, Staffan [Karolinska University Hospital, Department of Clinical Neuroscience, Karolinska Institutet, Department of Neuroradiology, Stockholm (Sweden); Le Blanc, Katarina [Karolinska University Hospital, Department of Stem Cell Research, Karolinska Institutet, Department of Clinical Immunology, Stockholm (Sweden)

2009-10-15

Transplantation procedures using intraparenchymal injection of stem cells result in tissue injury in addition to associated surgical risks. Intravenous injection of mesenchymal stem cells gives engraftment to lesions, but the method has low efficiency and specificity. In traumatic brain injuries (TBI), there is a transient breakdown of the blood-brain barrier and an inflammatory response, which increase migration of cells from blood to parenchyma. The aim of this investigation was to analyze the effect of intra-arterial administration on cellular engraftment. Experimental TBI was produced in a rat model. Endovascular technique was used to administer human mesenchymal stem cells in the ipsilateral internal carotid artery. Evaluation of engraftment and side effects were performed by immunohistochemical analysis of the brain and several other organs. The results were compared to intravenous administration of stem cells. Intra-arterial transplantion of mesenchymal stem cells resulted in central nervous system (CNS) engraftment without thromboembolic ischemia. We observed a significantly higher number of transplanted cells in the injured hemisphere after intra-arterial compared to intravenous administration both 1 day (p<0.01) and 5 days (p<0.05) after the transplantation. Some cells were also detected in the spleen but not in the other organs analyzed. Selective intra-arterial administration of mesenchymal stem cells to the injured CNS is a minimally invasive method for transplantation. The method is significantly more efficient than the intravenous route and causes no side effects in the current model. The technique can potentially be used for repeated transplantation to the CNS after TBI and in other diseases. (orig.)

Endovascular transplantation of stem cells to the injured rat CNS

International Nuclear Information System (INIS)

Lundberg, Johan; Soederman, Mikael; Andersson, Tommy; Holmin, Staffan; Le Blanc, Katarina

2009-01-01

Transplantation procedures using intraparenchymal injection of stem cells result in tissue injury in addition to associated surgical risks. Intravenous injection of mesenchymal stem cells gives engraftment to lesions, but the method has low efficiency and specificity. In traumatic brain injuries (TBI), there is a transient breakdown of the blood-brain barrier and an inflammatory response, which increase migration of cells from blood to parenchyma. The aim of this investigation was to analyze the effect of intra-arterial administration on cellular engraftment. Experimental TBI was produced in a rat model. Endovascular technique was used to administer human mesenchymal stem cells in the ipsilateral internal carotid artery. Evaluation of engraftment and side effects were performed by immunohistochemical analysis of the brain and several other organs. The results were compared to intravenous administration of stem cells. Intra-arterial transplantion of mesenchymal stem cells resulted in central nervous system (CNS) engraftment without thromboembolic ischemia. We observed a significantly higher number of transplanted cells in the injured hemisphere after intra-arterial compared to intravenous administration both 1 day (p<0.01) and 5 days (p<0.05) after the transplantation. Some cells were also detected in the spleen but not in the other organs analyzed. Selective intra-arterial administration of mesenchymal stem cells to the injured CNS is a minimally invasive method for transplantation. The method is significantly more efficient than the intravenous route and causes no side effects in the current model. The technique can potentially be used for repeated transplantation to the CNS after TBI and in other diseases. (orig.)

Direct numerical simulation of hypersonic boundary-layer flow on a flared cone

Energy Technology Data Exchange (ETDEWEB)

Pruett, C.D. [James Madison Univ., Harrisonburg, VA (United States). Dept. of Math. and Comput. Sci.; Chang Chau-Lyan [High Technology Corporation, Hampton, VA 23666 (United States)

1998-03-01

The forced transition of the boundary layer on an axisymmetric flared cone in Mach 6 flow is simulated by the method of spatial direct numerical simulation (DNS). The full effects of the flared afterbody are incorporated into the governing equations and boundary conditions; these effects include nonzero streamwise surface curvature, adverse streamwise pressure gradient, and decreasing boundary-layer edge Mach number. Transition is precipitated by periodic forcing at the computational inflow boundary with perturbations derived from parabolized stability equation (PSE) methodology and based, in part, on frequency spectra available from physical experiments. Significant qualitative differences are shown to exist between the present results and those obtained previously for a cone without afterbody flare. In both cases, the primary instability is of second-mode type; however, frequencies are much higher for the flared cone because of the decrease in boundary-layer thickness in the flared region. Moreover, Goertler modes, which are linearly stable for the straight cone, are unstable in regions of concave body flare. Reynolds stresses, which peak near the critical layer for the straight cone, exhibit peaks close to the wall for the flared cone. The cumulative effect appears to be that transition onset is shifted upstream for the flared cone. However, the length of the transition zone may possibly be greater because of the seemingly more gradual nature of the transition process on the flared cone. (orig.) With 20 figs., 28 refs.

Primary CNS lymphoma as a cause of Korsakoff syndrome.

Science.gov (United States)

Toth, Cory; Voll, Chris; Macaulay, Robert

2002-01-01

Korsakoff syndrome presents with memory dysfunction with retrograde amnesia, anterograde amnesia, limited insight into dysfunction, and confabulation. The most common etiology of Korsakoff syndrome is thiamine deficiency secondary to alcoholism. There are limited case reports of structural lesions causing Korsakoff syndrome. A 46-year-old male with a long history of alcoholism presented with a history of confusion, amnesia, and confabulation with no localizing features on neurological examination. The patient showed no clinical change with intravenous thiamine. Computed tomography of the brain revealed a heterogenous, enhancing mass lesion centered within the third ventricle, with other lesions found throughout cortical and subcortical regions. The patient was given dexamethasone i.v. without noticeable clinical improvement but with marked radiological improvement with mass reduction. Stereotactic biopsy revealed a diagnosis of primary central nervous system (CNS) lymphoma. Most patients presenting with Korsakoff syndrome have thiamine deficiency; however, mass lesions can produce an identical clinical picture. This is the first case report of a patient with primary CNS lymphoma presenting as Korsakoff syndrome.

[Structural CNS abnormalities responsible for coincidental occurrence of endocrine disorders, epilepsy and psychoneurologic disorders in children and adolescents].

Science.gov (United States)

Starzyk, Jerzy; Kwiatkowski, Stanisław; Kaciński, Marek; Kroczka, Sławomir; Wójcik, Małgorzata

2010-01-01

suprasellar arachnoid cyst (7 patients), septo-optic dysplasia (8 patients), craniopharyngioma (15 patients), glioma of the optic chiasm in neurofibromatosis type 1 (NF-1) (12 patients). There were no endocrine disorders in any of the ten patients with hamartoma of the hypothalamus and CPP. Endocrine and/ or neurological disorders did not resolve or were progressive after neurosurgery. Of 42 patients, a group of seven children representative for individual disorders was selected. In those patients, the etiology of both endocrine disorders, epilepsy and neuropsychiatric disorders was suspected to be common. 1. Various structural CNS abnormalities are the cause of concomitant epilepsy and endocrinopathy, although in some cases a direct impact of a genetic factor on the occurrence of both disorders or a mere coincidence cannot be ruled out. 2. Psychoneurological disorders usually precede the onset of endocrinopathy. 3. For this reason, MR or CT CNS imaging should be performed in any case of central neurological disorders, disorders of behavior, epilepsy, obsessive-compulsive syndrome, but also in patients with delayed psycho-motor development, delayed or accelerated growth and pubertal development. All of the above-mentioned manifestations may be symptoms of structural CNS abnormalities and their early treatment determines the child's future.

The Na+/Ca2+, K+ exchanger NCKX4 is required for efficient cone-mediated vision.

Science.gov (United States)

Vinberg, Frans; Wang, Tian; De Maria, Alicia; Zhao, Haiqing; Bassnett, Steven; Chen, Jeannie; Kefalov, Vladimir J

2017-06-26

Calcium (Ca 2+ ) plays an important role in the function and health of neurons. In vertebrate cone photoreceptors, Ca 2+ controls photoresponse sensitivity, kinetics, and light adaptation. Despite the critical role of Ca 2+ in supporting the function and survival of cones, the mechanism for its extrusion from cone outer segments is not well understood. Here, we show that the Na + /Ca 2+ , K + exchanger NCKX4 is expressed in zebrafish, mouse, and primate cones. Functional analysis of NCKX4-deficient mouse cones revealed that this exchanger is essential for the wide operating range and high temporal resolution of cone-mediated vision. We show that NCKX4 shapes the cone photoresponse together with the cone-specific NCKX2: NCKX4 acts early to limit response amplitude, while NCKX2 acts late to further accelerate response recovery. The regulation of Ca 2+ by NCKX4 in cones is a novel mechanism that supports their ability to function as daytime photoreceptors and promotes their survival.

Nuclear-Encoded Mitochondrial mRNAs: A Powerful Force in Axonal Growth and Development.

Science.gov (United States)

Gale, Jenna R; Aschrafi, Armaz; Gioio, Anthony E; Kaplan, Barry B

2018-04-01

Axons, their growth cones, and synaptic nerve terminals are neuronal subcompartments that have high energetic needs. As such, they are enriched in mitochondria, which supply the ATP necessary to meet these demands. To date, a heterogeneous population of nuclear-encoded mitochondrial mRNAs has been identified in distal axons and growth cones. Accumulating evidence suggests that the local translation of these mRNAs is required for mitochondrial maintenance and axonal viability. Here, we review evidence that suggests a critical role for axonal translation of nuclear-encoded mitochondrial mRNAs in axonal growth and development. Additionally, we explore the role that site-specific translation at the mitochondria itself may play in this process. Finally, we briefly review the clinical implications of dysregulation of local translation of mitochondrial-related mRNAs in neurodevelopmental disorders.

Large Scale Plasmonic nanoCones array For Spectroscopy Detection

KAUST Repository

Das, Gobind

2015-09-24

Advanced optical materials or interfaces are gaining attention for diagnostic applications. However, the achievement of large device interface as well as facile surface functionalization largely impairs their wide use. The present work is aimed to address different innovative aspects related to the fabrication of large area 3D plasmonic arrays, their direct and easy functionalization with capture elements and their spectroscopic verifications through enhanced Raman and enhanced fluorescence techniques. In detail we have investigated the effect of Au-based nanoCones array, fabricated by means of direct nanoimprint technique over large area (mm2), on protein capturing and on the enhancement in optical signal. A selective functionalization of gold surfaces was proposed by using a peptide (AuPi3) previously selected by phage display. In this regard, two different sequences, labeled with fluorescein and biotin, were chemisorbed on metallic surfaces. The presence of Au nanoCones array consents an enhancement in electric field on the apex of cone, enabling the detection of molecules. We have witnessed around 12-fold increase in fluorescence intensity and SERS enhancement factor around 1.75 ×105 with respect to the flat gold surface. Furthermore, a sharp decrease in fluorescence lifetime over nanoCones confirms the increase in radiative emission (i.e. an increase in photonics density at the apex of cones).

Large Scale Plasmonic nanoCones array For Spectroscopy Detection

KAUST Repository

Das, Gobind; Battista, Edmondo; Manzo, Gianluigi; Causa, Filippo; Netti, Paolo; Di Fabrizio, Enzo M.

2015-01-01

Advanced optical materials or interfaces are gaining attention for diagnostic applications. However, the achievement of large device interface as well as facile surface functionalization largely impairs their wide use. The present work is aimed to address different innovative aspects related to the fabrication of large area 3D plasmonic arrays, their direct and easy functionalization with capture elements and their spectroscopic verifications through enhanced Raman and enhanced fluorescence techniques. In detail we have investigated the effect of Au-based nanoCones array, fabricated by means of direct nanoimprint technique over large area (mm2), on protein capturing and on the enhancement in optical signal. A selective functionalization of gold surfaces was proposed by using a peptide (AuPi3) previously selected by phage display. In this regard, two different sequences, labeled with fluorescein and biotin, were chemisorbed on metallic surfaces. The presence of Au nanoCones array consents an enhancement in electric field on the apex of cone, enabling the detection of molecules. We have witnessed around 12-fold increase in fluorescence intensity and SERS enhancement factor around 1.75 ×105 with respect to the flat gold surface. Furthermore, a sharp decrease in fluorescence lifetime over nanoCones confirms the increase in radiative emission (i.e. an increase in photonics density at the apex of cones).

Light-cone gauge approach to arbitrary spin fields, currents and shadows

International Nuclear Information System (INIS)

Metsaev, R R

2014-01-01

Totally symmetric arbitrary spin fields in AdS space, conformal fields, conformal currents, and shadow fields in flat space are studied. Light-cone gauge formulations for such fields, currents and shadows are obtained. Use of the Poincaré parametrization of AdS space and ladder operators allows us to treat fields in flat and AdS spaces on an equal footing. Light-cone gauge realization of relativistic symmetries for fields, currents and shadows is also obtained. The light-cone gauge formulation for fields is obtained by using the gauge invariant Lagrangian which is presented in terms of modified de Donder divergence, while the light-cone gauge formulation for currents and shadows is obtained by using the gauge invariant approach to currents and shadows. This allows us to demonstrate explicitly how the ladder operators entering the gauge invariant formulation of fields, currents and shadows manifest themselves in the light-cone gauge formulation for fields, currents and shadows. (paper)

Retinal cone photoreceptors of the deer mouse Peromyscus maniculatus: development, topography, opsin expression and spectral tuning.

Directory of Open Access Journals (Sweden)

Patrick Arbogast

Full Text Available A quantitative analysis of photoreceptor properties was performed in the retina of the nocturnal deer mouse, Peromyscus maniculatus, using pigmented (wildtype and albino animals. The aim was to establish whether the deer mouse is a more suitable model species than the house mouse for photoreceptor studies, and whether oculocutaneous albinism affects its photoreceptor properties. In retinal flatmounts, cone photoreceptors were identified by opsin immunostaining, and their numbers, spectral types, and distributions across the retina were determined. Rod photoreceptors were counted using differential interference contrast microscopy. Pigmented P. maniculatus have a rod-dominated retina with rod densities of about 450.000/mm(2 and cone densities of 3000-6500/mm(2. Two cone opsins, shortwave sensitive (S and middle-to-longwave sensitive (M, are present and expressed in distinct cone types. Partial sequencing of the S opsin gene strongly supports UV sensitivity of the S cone visual pigment. The S cones constitute a 5-15% minority of the cones. Different from house mouse, S and M cone distributions do not have dorsoventral gradients, and coexpression of both opsins in single cones is exceptional (<2% of the cones. In albino P. maniculatus, rod densities are reduced by approximately 40% (270.000/mm(2. Overall, cone density and the density of cones exclusively expressing S opsin are not significantly different from pigmented P. maniculatus. However, in albino retinas S opsin is coexpressed with M opsin in 60-90% of the cones and therefore the population of cones expressing only M opsin is significantly reduced to 5-25%. In conclusion, deer mouse cone properties largely conform to the general mammalian pattern, hence the deer mouse may be better suited than the house mouse for the study of certain basic cone properties, including the effects of albinism on cone opsin expression.

Cones fabricated by 3D nanoimprint lithography for highly sensitive surface enhanced Raman spectroscopy

International Nuclear Information System (INIS)

Wu Wei; Hu Min; Ou Fungsuong; Li Zhiyong; Williams, R Stanley

2010-01-01

We demonstrated a cost-effective and deterministic method of patterning 3D cone arrays over a large area by using nanoimprint lithography (NIL). Cones with tip radius of less than 10 nm were successfully duplicated onto the UV-curable imprint resist materials from the silicon cone templates. Such cone structures were shown to be a versatile platform for developing reliable, highly sensitive surface enhanced Raman spectroscopy (SERS) substrates. In contrast to the silicon nanocones, the SERS substrates based on the Au coated cones made by the NIL offered significant improvement of the SERS signal. A further improvement of the SERS signal was observed when the polymer cones were imprinted onto a reflective metallic mirror surface. A sub-zeptomole detection sensitivity for a model molecule, trans-1,2-bis(4-pyridyl)-ethylene (BPE), on the Au coated NIL cone surfaces was achieved.

Laser bistatic two-dimensional scattering imaging simulation of lambert cone

Science.gov (United States)

Gong, Yanjun; Zhu, Chongyue; Wang, Mingjun; Gong, Lei

2015-11-01

This paper deals with the laser bistatic two-dimensional scattering imaging simulation of lambert cone. Two-dimensional imaging is called as planar imaging. It can reflect the shape of the target and material properties. Two-dimensional imaging has important significance for target recognition. The expression of bistatic laser scattering intensity of lambert cone is obtained based on laser radar eauqtion. The scattering intensity of a micro-element on the target could be obtained. The intensity is related to local angle of incidence, local angle of scattering and the infinitesimal area on the cone. According to the incident direction of laser, scattering direction and normal of infinitesimal area, the local incidence angle and scattering angle can be calculated. Through surface integration and the introduction of the rectangular function, we can get the intensity of imaging unit on the imaging surface, and then get Lambert cone bistatic laser two-dimensional scattering imaging simulation model. We analyze the effect of distinguishability, incident direction, observed direction and target size on the imaging. From the results, we can see that the scattering imaging simulation results of the lambert cone bistatic laser is correct.

Off-shell spinor-helicity amplitudes from light-cone deformation procedure

Energy Technology Data Exchange (ETDEWEB)

Ponomarev, Dmitry [Theoretical physics group, Blackett Laboratory, Imperial College London,London, SW7 2AZ (United Kingdom)

2016-12-22

We study the consistency conditions for interactions of massless fields of any spin in four-dimensional flat space using the light-cone approach. We show that they can be equivalently rewritten as the Ward identities for the off-shell light-cone amplitudes built from the light-cone Hamiltonian in the standard way. Then we find a general solution of these Ward identities. The solution admits a compact representation when written in the spinor-helicity form and is given by an arbitrary function of spinor products, satisfying well-known homogeneity constraints. Thus, we show that the light-cone consistent deformation procedure inevitably leads to a certain off-shell version of the spinor-helicity approach. We discuss how the relation between the two approaches can be employed to facilitate the search of consistent interaction of massless higher-spin fields.

A fast and efficient method for sequential cone-beam tomography

International Nuclear Information System (INIS)

Koehler, Th.; Proksa, R.; Grass, M.

2001-01-01

Sequential cone-beam tomography is a method that uses data of two or more parallel circular trajectories of a cone-beam scanner to reconstruct the object function. We propose a condition for the data acquisition that ensures that all object points between two successive circles are irradiated over an angular span of the x-ray source position of exactly 360 deg. in total as seen along the rotation axis. A fast and efficient approximative reconstruction method for the proposed acquisition is presented which uses data from exactly 360 deg. for every object point. It is based on the Tent-FDK method which was recently developed for single circular cone-beam CT. The measurement geometry does not provide sufficient data for exact reconstruction but it is shown that the proposed reconstruction method provides satisfying image quality for small cone angles

CSF Hypocretin-1 Levels and Clinical Profiles in Narcolepsy and Idiopathic CNS Hypersomnia in Norway

Science.gov (United States)

Heier, Mona Skard; Evsiukova, Tatiana; Vilming, Steinar; Gjerstad, Michaela D.; Schrader, Harald; Gautvik, Kaare

2007-01-01

Objective: To evaluate the relationship between CSF hypocretin-1 levels and clinical profiles in narcolepsy and CNS hypersomnia in Norwegian patients. Method: CSF hypocretin-1 was measured by a sensitive radioimmunoassay in 47 patients with narcolepsy with cataplexy, 7 with narcolepsy without cataplexy, 10 with idiopathic CNS hypersomnia, and a control group. Results: Low hypocretin-1 values were found in 72% of the HLA DQB1*0602 positive patients with narcolepsy and cataplexy. Patients with low CSF hypocretin-1 levels reported more extensive muscular involvement during cataplectic attacks than patients with normal levels. Hypnagogic hallucinations and sleep paralysis occurred more frequently in patients with cataplexy than in the other patient groups, but with no correlation to hypocretin-1 levels. Conclusion: About three quarters of the HLA DQB1*0602 positive patients with narcolepsy and cataplexy had low CSF hypocretin-1 values, and appear to form a distinct clinical entity. Narcolepsy without cataplexy could not be distinguished from idiopathic CNS hypersomnia by clinical symptoms or biochemical findings. Citation: Heier MS; Evsiukova T; Vilming S; Gjerstad MD; Schrader H; Gautvik K. CSF hypocretin-1 levels and clinical profiles in narcolepsy and idiopathic CNS hypersomnia in norway. SLEEP 2007;30(8):969-973. PMID:17702265

Palmitoylethanolamide in CNS health and disease.

Science.gov (United States)

Mattace Raso, Giuseppina; Russo, Roberto; Calignano, Antonio; Meli, Rosaria

2014-08-01

The existence of acylethanolamides (AEs) in the mammalian brain has been known for decades. Among AEs, palmitoylethanolamide (PEA) is abundant in the central nervous system (CNS) and conspicuously produced by neurons and glial cells. Antihyperalgesic and neuroprotective properties of PEA have been mainly related to the reduction of neuronal firing and to control of inflammation. Growing evidence suggest that PEA may be neuroprotective during CNS neurodegenerative diseases. Advances in the understanding of the physiology and pharmacology of PEA have potentiated its interest as useful biological tool for disease management. Several rapid non-genomic and delayed genomic mechanisms of action have been identified for PEA as peroxisome proliferator-activated receptor (PPAR)-α dependent. First, an early molecular control, through Ca(+2)-activated intermediate- and/or big-conductance K(+) channels opening, drives to rapid neuronal hyperpolarization. This is reinforced by the increase of the inward Cl(-) currents due to the modulation of the gamma aminobutyric acid A receptor and by the desensitization of the transient receptor potential channel type V1. Moreover, the gene transcription-mediated mechanism sustains the long-term anti-inflammatory effects, by reducing pro-inflammatory enzyme expression and increasing neurosteroid synthesis. Overall, the integration of these different modes of action allows PEA to exert an immediate and prolonged efficacious control in neuron signaling either on inflammatory process or neuronal excitability, maintaining cellular homeostasis. In this review, we will discuss the effect of PEA on metabolism, behavior, inflammation and pain perception, related to the control of central functions and the emerging evidence demonstrating its therapeutic efficacy in several neurodegenerative diseases. Copyright © 2014. Published by Elsevier Ltd.

Clinical utility of dental cone-beam computed tomography: current perspectives

Directory of Open Access Journals (Sweden)

Jaju PP

2014-04-01

Full Text Available Prashant P Jaju,1 Sushma P Jaju21Oral Medicine and Radiology, 2Conservative Dentistry and Endodontics, Rishiraj College of Dental Sciences and Research Center, Bhopal, IndiaAbstract: Panoramic radiography and computed tomography were the pillars of maxillofacial diagnosis. With the advent of cone-beam computed tomography, dental practice has seen a paradigm shift. This review article highlights the potential applications of cone-beam computed tomography in the fields of dental implantology and forensic dentistry, and its limitations in maxillofacial diagnosis.Keywords: dental implants, cone-beam computed tomography, panoramic radiography, computed tomography

Multiple cone pathways are involved in photic regulation of retinal dopamine.

Science.gov (United States)

Qiao, Sheng-Nan; Zhang, Zhijing; Ribelayga, Christophe P; Zhong, Yong-Mei; Zhang, Dao-Qi

2016-06-30

Dopamine is a key neurotransmitter in the retina and plays a central role in the light adaptive processes of the visual system. The sole source of retinal dopamine is dopaminergic amacrine cells (DACs). We and others have previously demonstrated that DACs are activated by rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs) upon illumination. However, it is still not clear how each class of photosensitive cells generates light responses in DACs. We genetically isolated cone function in mice to specifically examine the cone-mediated responses of DACs and their neural pathways. In addition to the reported excitatory input to DACs from light-increment (ON) bipolar cells, we found that cones alternatively signal to DACs via a retrograde signalling pathway from ipRGCs. Cones also produce ON and light-decrement (OFF) inhibitory responses in DACs, which are mediated by other amacrine cells, likely driven by type 1 and type 2/3a OFF bipolar cells, respectively. Dye injections indicated that DACs had similar morphological profiles with or without ON/OFF inhibition. Our data demonstrate that cones utilize specific parallel excitatory and inhibitory circuits to modulate DAC activity and efficiently regulate dopamine release and the light-adaptive state of the retina.

Sleep disorders in children after treatment for a CNS tumour

NARCIS (Netherlands)

Verberne, Lisa M.; Maurice-Stam, Heleen; Grootenhuis, Martha A.; van Santen, Hanneke M.; Schouten-van Meeteren, Antoinette Y. N.

2012-01-01

The long-term survival of children with a central nervous system (CNS) tumour is improving. However, they experience late effects, including altered habits and patterns of sleep. We evaluated the presence and type of sleep disorders and daytime sleepiness in these children, and its associations with

Cone pigments in a North American marsupial, the opossum (Didelphis virginiana)

OpenAIRE

Jacobs, Gerald H.; Williams, Gary A.

2010-01-01

Only two of the four cone opsin gene families found in vertebrates are represented in contemporary eutherian and marsupial species. Recent genetic studies of two species of South American marsupial detected the presence of representatives from two of the classes of cone opsin genes and the structures of these genes predicted cone pigments with respective peaks in the ultraviolet and long-wavelength portions of the spectrum. The Virginia opossum (Didelphis virginiana), a profoundly nocturnal a...

Extrafoveal Cone Packing in Eyes With a History of Retinopathy of Prematurity.

Science.gov (United States)

Ramamirtham, Ramkumar; Akula, James D; Soni, Garima; Swanson, Matthew J; Bush, Jennifer N; Moskowitz, Anne; Swanson, Emily A; Favazza, Tara L; Tavormina, Jena L; Mujat, Mircea; Ferguson, R Daniel; Hansen, Ronald M; Fulton, Anne B

2016-02-01

To study the density and packing geometry of the extrafoveal cone photoreceptors in eyes with a history of retinopathy of prematurity (ROP). We used a multimodal combination of adaptive optics (AO) scanning light ophthalmoscopy (SLO) and optical coherence tomography (OCT). Cones were identified in subjects (aged 14-26 years) with a history of ROP that was either severe and treated by laser ablation of avascular peripheral retina (TROP; n = 5) or mild and spontaneously resolved, untreated (UROP; n = 5), and in term-born controls (CT; n = 8). The AO-SLO images were obtained at temporal eccentricities 4.5°, 9°, 13.5°, and 18° using both confocal and offset apertures with simultaneous, colocal OCT images. Effects of group, eccentricity, and aperture were evaluated and the modalities compared. In the SLO images, cone density was lower and the packing pattern less regular in TROP, relative to CT and UROP retinae. Although SLO image quality appeared lower in TROP, root mean square (RMS) wavefront error did not differ among the groups. In TROP eyes, cone discrimination was easier in offset aperture images. There was no evidence of cone loss in the TROP OCT images. Low cone density in TROP confocal SLO images may have resulted from lower image quality. Since AO correction in these eyes was equivalent to that of the control group, and OCT imaging showed no significant cone loss, the optical properties of the inner retina or properties of the cones themselves are likely altered in a way that affects photoreceptor imaging.

Field Test Evaluation of Effect on Cone Resistance Caused by Change in Penetration Rate

DEFF Research Database (Denmark)

Poulsen, Rikke; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

2012-01-01

in the laboratory. A change in the measured cone resistance occurs by lowering the penetration rate. This is caused by the changes in drainage conditions. Compared to the normal penetration rate of 20 mm/s, this paper illustrates that lowering the penetration rate leads to an increase in the cone resistance from 1......This paper presents how a change in cone penetration rate affects the measured cone resistance during cone penetration testing in silty soils. Regardless of soil, type the standard rate of penetration is 20 mm/s and it is generally accepted that undrained penetration occurs in clay while drained...... penetration occurs in sand. In intermediate soils such as silty soils, the standard cone penetration rate may result in drainage conditions varying from undrained to partially or fully drained conditions. Field cone penetrations tests have been conducted with different penetration rates on a test site...

Growth of Megaspherulites In a Rhyolitic Vitrophyre

Science.gov (United States)

Smith, Robert K.; Tremallo, Robin L.; Lofgren, Gary E.

2000-01-01

Megaspherulites occur in the middle zone of a thick sequence of rhyolitic vitrophyre that occupies a small, late Eocene to early Oligocene volcanic-tectonic basin near Silver Cliff, Custer County, Colorado. Diameters of the megaspherulites range from 0.3 m to over 3.66 m, including a clay envelope. The megaspherulites are compound spherulites. consisting of an extremely large number (3.8 x 10(exp 9) to 9.9 x 10(exp 9)) of individual growth cones averaging 3 mm long by 1.25 mm wide at their termination. They are holocrystalline, very fine- to fine-grained, composed of disordered to ordered sanidine (orthoclase) and quartz, and surrounded by a thin K-feldspar, quartz rich rind, an inner clay layer with mordenite, and an outer clay layer composed wholly of 15 A montmorillonite. Whole rock analyses of the megaspherulites show a restricted composition from their core to their outer edge, with an average analyses of 76.3% SiO2, 0.34% CaO, 2.17% Na2O, 6.92% K2O, 0.83% H2O+ compared to the rhyolitic vitrophyre from which they crystallize with 71.07% SiO2, 0.57% CaO, 4.06% Na2O,4.l0% K2O, and 6.40% H2O+. The remaining oxides of Fe2O3 (total Fe), A12O3, MnO,MgO, TiO2, P2O5, Cr2O3, and trace elements show uniform distribution between the megaspherulites and the rhyolitic vitrophyre. Megaspherulite crystallization began soon after the rhyolitic lava ceased to flow as the result of sparse heterogeneous nucleation, under nonequilibrium conditions, due to a high degree of undercooling, delta T. The crystals grow with a fibrous habit which is favored by a large delta T ranging between 245 C and 295 C, despite lowered viscosity, and enhanced diffusion due to the high H2O content, ranging between 5% and 7%. Therefore, megaspherulite growth proceeded in a diffusion controlled manner, where the diffusion, rate lags behind the crystal growth rate at the crystal-liquid interface, restricting fibril lengths and diameters to the 10 micron to 15 micron and 3 micron and 8 micron ranges

New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs

NARCIS (Netherlands)

Sturm, Dominik; Orr, Brent A.; Toprak, Umut H.; Hovestadt, Volker; Jones, David T. W.; Capper, David; Sill, Martin; Buchhalter, Ivo; Northcott, Paul A.; Leis, Irina; Ryzhova, Marina; Koelsche, Christian; Pfaff, Elke; Allen, Sariah J.; Balasubramanian, Gnanaprakash; Worst, Barbara C.; Pajtler, Kristian W.; Brabetz, Sebastian; Johann, Pascal D.; Sahm, Felix; Reimand, Jüri; Mackay, Alan; Carvalho, Diana M.; Remke, Marc; Phillips, Joanna J.; Perry, Arie; Cowdrey, Cynthia; Drissi, Rachid; Fouladi, Maryam; Giangaspero, Felice; Łastowska, Maria; Grajkowska, Wiesława; Scheurlen, Wolfram; Pietsch, Torsten; Hagel, Christian; Gojo, Johannes; Lötsch, Daniela; Berger, Walter; Slavc, Irene; Haberler, Christine; Jouvet, Anne; Holm, Stefan; Hofer, Silvia; Prinz, Marco; Keohane, Catherine; Fried, Iris; Mawrin, Christian; Scheie, David; Mobley, Bret C.; Schniederjan, Matthew J.; Santi, Mariarita; Buccoliero, Anna M.; Dahiya, Sonika; Kramm, Christof M.; von Bueren, André O.; von Hoff, Katja; Rutkowski, Stefan; Herold-Mende, Christel; Frühwald, Michael C.; Milde, Till; Hasselblatt, Martin; Wesseling, Pieter; Rößler, Jochen; Schüller, Ulrich; Ebinger, Martin; Schittenhelm, Jens; Frank, Stephan; Grobholz, Rainer; Vajtai, Istvan; Hans, Volkmar; Schneppenheim, Reinhard; Zitterbart, Karel; Collins, V. Peter; Aronica, Eleonora; Varlet, Pascale; Puget, Stephanie; Dufour, Christelle; Grill, Jacques; Figarella-Branger, Dominique; Wolter, Marietta; Schuhmann, Martin U.; Shalaby, Tarek; Grotzer, Michael; van Meter, Timothy; Monoranu, Camelia-Maria; Felsberg, Jörg; Reifenberger, Guido; Snuderl, Matija; Forrester, Lynn Ann; Koster, Jan; Versteeg, Rogier; Volckmann, Richard; van Sluis, Peter; Wolf, Stephan; Mikkelsen, Tom; Gajjar, Amar; Aldape, Kenneth; Moore, Andrew S.; Taylor, Michael D.; Jones, Chris; Jabado, Nada; Karajannis, Matthias A.; Eils, Roland; Schlesner, Matthias; Lichter, Peter; von Deimling, Andreas; Pfister, Stefan M.; Ellison, David W.; Korshunov, Andrey; Kool, Marcel

2016-01-01

Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of institutionally

New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs

NARCIS (Netherlands)

Sturm, Dominik; Orr, Brent A.; Toprak, Umut H.; Hovestadt, Volker; Jones, David T W; Capper, David; Sill, Martin; Buchhalter, Ivo; Northcott, Paul A.; Leis, Irina; Ryzhova, Marina; Koelsche, Christian; Pfaff, Elke; Allen, Sariah J.; Balasubramanian, Gnanaprakash; Worst, Barbara C.; Pajtler, Kristian W.; Brabetz, Sebastian; Johann, Pascal D.; Sahm, Felix; Reimand, Jüri; Mackay, Alan; Carvalho, Diana M.; Remke, Marc; Phillips, Joanna J.; Perry, Arie; Cowdrey, Cynthia; Drissi, Rachid; Fouladi, Maryam; Giangaspero, Felice; Łastowska, Maria; Grajkowska, Wiesława; Scheurlen, Wolfram; Pietsch, Torsten; Hagel, Christian; Gojo, Johannes; Lötsch, Daniela; Berger, Walter; Slavc, Irene; Haberler, Christine; Jouvet, Anne; Holm, Stefan; Hofer, Silvia; Prinz, Marco; Keohane, Catherine; Fried, Iris; Mawrin, Christian; Scheie, David; Mobley, Bret C.; Schniederjan, Matthew J.; Santi, Mariarita; Buccoliero, Anna M.; Dahiya, Sonika; Kramm, Christof M.; Von Bueren, André O.; Von Hoff, Katja; Rutkowski, Stefan; Herold-Mende, Christel; Frühwald, Michael C.; Milde, Till; Hasselblatt, Martin; Wesseling, Pieter; Rößler, Jochen; Schüller, Ulrich; Ebinger, Martin; Schittenhelm, Jens; Frank, Stephan; Grobholz, Rainer; Vajtai, Istvan; Hans, Volkmar; Schneppenheim, Reinhard; Zitterbart, Karel; Collins, V. Peter; Aronica, Eleonora; Varlet, Pascale; Puget, Stephanie; Dufour, Christelle; Grill, Jacques; Figarella-Branger, Dominique; Wolter, Marietta; Schuhmann, Martin U.; Shalaby, Tarek; Grotzer, Michael; Van Meter, Timothy; Monoranu, Camelia Maria; Felsberg, Jörg; Reifenberger, Guido; Snuderl, Matija; Forrester, Lynn Ann; Koster, Jan; Versteeg, Rogier; Volckmann, Richard; Van Sluis, Peter; Wolf, Stephan; Mikkelsen, Tom; Gajjar, Amar; Aldape, Kenneth; Moore, Andrew S.; Taylor, Michael D.; Jones, Chris; Jabado, Nada; Karajannis, Matthias A.; Eils, Roland; Schlesner, Matthias; Lichter, Peter; Von Deimling, Andreas; Pfister, Stefan M.; Ellison, David W.; Korshunov, Andrey; Kool, Marcel

2016-01-01

Summary Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of

Hadronic wavefunctions in light-cone quantization

International Nuclear Information System (INIS)

Hyer, T.

1994-05-01

The analysis of light-cone wavefunctions seems the most promising theoretical approach to a detailed understanding of the structure of relativistic bound states, particularly hadrons. However, there are numerous complications in this approach. Most importantly, the light-cone approach sacrifices manifest rotational invariance in exchange for the elimination of negative-energy states. The requirement of rotational invariance of the full theory places important constraints on proposed light-cone wavefunctions, whether they are modelled or extracted from some numerical procedure. A formulation of the consequences of the hidden rotational symmetry has been sought for some time; it is presented in Chapter 2. In lattice gauge theory or heavy-quark effective theory, much of the focus is on the extraction of numerical values of operators which are related to the hadronic wavefunction. These operators are to some extent interdependent, with relations induced by fundamental constraints on the underlying wavefunction. The consequences of the requirement of unitarity are explored in Chapter 3, and are found to have startling phenomenological relevance. To test model light-cone wavefunctions, experimental predictions must be made. The reliability of perturbative QCD as a tool for making such predictions has been questioned. In Chapter 4, the author presents a computation of the rates for nucleon-antinucleon annihilation, improving the reliability of the perturbative computation by taking into account the Sudakov suppression of exclusive processes at large transverse impact parameter. In Chapter 5, he develops the analysis of semiexclusive production. This work focuses on processes in which a single isolated meson is produced perturbatively and recoils against a wide hadronizing system. At energies above about 10 GeV, semiexclusive processes are shown to be the most sensitive experimental probes of hadronic structure

4th ENRI International Workshop on ATM/CNS

CERN Document Server

2017-01-01

This book is a compilation of selected papers from the 4th ENRI International Workshop on ATM/CNS (EIWAC2015). The work focuses on novel techniques for aviation infrastructure in air traffic management (ATM) and communications, navigation, surveillance, and informatics (CNSI) domains. The contents make valuable contributions to academic researchers, engineers in the industry, and regulators of aviation authorities. As well, readers will encounter new ideas for realizing a more efficient and safer aviation system. .

Enhanced photon production rate on the light-cone

International Nuclear Information System (INIS)

Aurenche, P.; Grenoble-1 Univ., 74 - Annecy; Gelis, F.; Kobes, R.; Petitgirard, E.

1996-01-01

Recent studies of the high temperature soft photon production rate on the light cone using Braaten-Pisarski resummation techniques have found collinear divergences present. It is shown that there exist a class of terms outside the Braaten-Pisarski framework which, although also divergent, dominate over these previously considered terms. The divergences in these new terms may be alleviated by application of a recently developed resummation scheme for processes sensitive to the light-cone. (author)

Enhancement of the Number of Fast Electrons Generated in a Laser Inverse Cone Interaction

International Nuclear Information System (INIS)

Yan-Ling, Ji; Gang, Jiang; Wei-Dong, Wu; Ji-Cheng, Zhang; Yong-Jian, Tang

2010-01-01

Enhancement of the energy-conversion efficiency from laser to target electrons is demonstrated by two-dimensional particle-in-cell simulations in a laser-inverse cone interaction. When an intense short-pulse laser illuminates the inverse cone target, the electrons at the cone end are accelerated by the ponderomotive force. Then these electrons are guided and confined to transport along the inverse cone walls by the induced electromagnetic fields. A device consisting of inverse hollow-cone and multihole array plasma is proposed in order to increase the energy-conversion efficiency from laser to electrons. Particle-in-cell simulations present that the multiholes transpiercing the cone end help to enhance the number of fast electrons and the maximum electron energy significantly. (physics of gases, plasmas, and electric discharges)

A new approximate algorithm for image reconstruction in cone-beam spiral CT at small cone-angles

International Nuclear Information System (INIS)

Schaller, S.; Flohr, T.; Steffen, P.

1996-01-01

This paper presents a new approximate algorithm for image reconstruction with cone-beam spiral CT data at relatively small cone-angles. Based on the algorithm of Wang et al., our method combines a special complementary interpolation with filtered backprojection. The presented algorithm has three main advantages over Wang's algorithm: (1) It overcomes the pitch limitation of Wang's algorithm. (2) It significantly improves z-resolution when suitable sampling schemes are applied. (3) It avoids the waste of applied radiation dose inherent to Wang's algorithm. Usage of the total applied dose is an important requirement in medical imaging. Our method has been implemented on a standard workstation. Reconstructions of computer-simulated data of different phantoms, assuming sampling conditions and image quality requirements typical to medical CT, show encouraging results

Generalized Fourier slice theorem for cone-beam image reconstruction.

Science.gov (United States)

Zhao, Shuang-Ren; Jiang, Dazong; Yang, Kevin; Yang, Kang

2015-01-01

The cone-beam reconstruction theory has been proposed by Kirillov in 1961, Tuy in 1983, Feldkamp in 1984, Smith in 1985, Pierre Grangeat in 1990. The Fourier slice theorem is proposed by Bracewell 1956, which leads to the Fourier image reconstruction method for parallel-beam geometry. The Fourier slice theorem is extended to fan-beam geometry by Zhao in 1993 and 1995. By combining the above mentioned cone-beam image reconstruction theory and the above mentioned Fourier slice theory of fan-beam geometry, the Fourier slice theorem in cone-beam geometry is proposed by Zhao 1995 in short conference publication. This article offers the details of the derivation and implementation of this Fourier slice theorem for cone-beam geometry. Especially the problem of the reconstruction from Fourier domain has been overcome, which is that the value of in the origin of Fourier space is 0/0. The 0/0 type of limit is proper handled. As examples, the implementation results for the single circle and two perpendicular circle source orbits are shown. In the cone-beam reconstruction if a interpolation process is considered, the number of the calculations for the generalized Fourier slice theorem algorithm is O(N^4), which is close to the filtered back-projection method, here N is the image size of 1-dimension. However the interpolation process can be avoid, in that case the number of the calculations is O(N5).

Fabrication and Application of Iron(III-Oxide Nanoparticle/Polydimethylsiloxane Composite Cone in Microfluidic Channels

Directory of Open Access Journals (Sweden)

Cheng-Chun Huang

2012-01-01

Full Text Available This paper presented the fabrication and applications of an iron(III-oxide nanoparticle/polydimethylsiloxane (PDMS cone as a component integrated in lab on a chip. The two main functions of this component were to capture magnetic microbeads in the microfluid and to mix two laminar fluids by generating disturbance. The iron(III-oxide nanoparticle/PDMS cone was fabricated by automatic dispensing and magnetic shaping. Three consecutive cones of 300 μm in height were asymmetrically placed along a microchannel of 2 mm in width and 1.1 mm in height. Flow passing the cones was effectively redistributed for Renolds number lower than . Streptavidin-coated magnetic microbeads which were bound with biotin were successfully captured by the composite cones as inspected under fluorescence microscope. The process parameters for fabricating the composite cones were investigated. The fabricated cone in the microchannel could be applied in lab on a chip for bioassay in the future.

Development of partial ontogenic resistance to powdery mildew in hop cones and its management implications.

Directory of Open Access Journals (Sweden)

Megan C Twomey

Full Text Available Knowledge of processes leading to crop damage is central to devising rational approaches to disease management. Multiple experiments established that infection of hop cones by Podosphaera macularis was most severe if inoculation occurred within 15 to 21 days after bloom. This period of infection was associated with the most pronounced reductions in alpha acids, cone color, and accelerated maturation of cones. Susceptibility of cones to powdery mildew decreased progressively after the transition from bloom to cone development, although complete immunity to the disease failed to develop. Maturation of cone tissues was associated with multiple significant affects on the pathogen manifested as reduced germination of conidia, diminished frequency of penetration of bracts, lengthening of the latent period, and decreased sporulation. Cones challenged with P. macularis in juvenile developmental stages also led to greater frequency of colonization by a complex of saprophytic, secondary fungi. Since no developmental stage of cones was immune to powdery mildew, the incidence of powdery mildew continued to increase over time and exceeded 86% by late summer. In field experiments with a moderately susceptible cultivar, the incidence of cones with powdery mildew was statistically similar when fungicide applications were made season-long or targeted only to the juvenile stages of cone development. These studies establish that partial ontogenic resistance develops in hop cones and may influence multiple phases of the infection process and pathogen reproduction. The results further reinforce the concept that the efficacy of a fungicide program may depend largely on timing of a small number of sprays during a relatively brief period of cone development. However in practice, targeting fungicide and other management tactics to periods of enhanced juvenile susceptibility may be complicated by a high degree of asynchrony in cone development and other factors that are

Chloride currents in cones modify feedback from horizontal cells to cones in goldfish retina

NARCIS (Netherlands)

Endeman, Duco; Fahrenfort, Iris; Sjoerdsma, Trijntje; Steijaert, Marvin; ten Eikelder, Huub; Kamermans, Maarten

2012-01-01

In neuronal systems, excitation and inhibition must be well balanced to ensure reliable information transfer. The cone/horizontal cell (HC) interaction in the retina is an example of this. Because natural scenes encompass an enormous intensity range both in temporal and spatial domains, the balance

The nature of surround-induced depolarizing responses in goldfish cones

NARCIS (Netherlands)

Kraaij, D. A.; Spekreijse, H.; Kamermans, M.

2000-01-01

Cones in the vertebrate retina project to horizontal and bipolar cells and the horizontal cells feedback negatively to cones. This organization forms the basis for the center/surround organization of the bipolar cells, a fundamental step in the visual signal processing. Although the surround

Pivotal roles of Fezf2 in differentiation of cone OFF bipolar cells and functional maturation of cone ON bipolar cells in retina.

Science.gov (United States)

Suzuki-Kerr, Haruna; Iwagawa, Toshiro; Sagara, Hiroshi; Mizota, Atsushi; Suzuki, Yutaka; Watanabe, Sumiko

2018-06-01

During development of the retina, common retinal progenitor cells give rise to six classes of neurons that subsequently further diversify into more than 55 subtypes of neuronal subtypes. Here, we have investigated the expression and function of Fezf2, Fez zinc finger family of protein, in the developing mouse retina. Expression of Fezf2 transcripts was strongly observed in the embryonic retinal progenitors at E14.5 and declined quickly in subsequent development of retina. Then, in postnatal stage at around day 8, Fezf2 was transiently expressed then declined again. Loss-of-function analysis using retinas from mice in which Fezf2 coding region was substituted with β-galactosidase showed that Fezf2 is expressed in a subset of cone OFF bipolar cells and required for their differentiation. Using electroretinogram, we found that Fezf2 knockout retina exhibited significantly reduced photopic b-wave, suggesting functional abnormality of cone ON bipolar cells. Furthermore, reduced expression of synaptic protein Trpm1 and structural alteration of ON bipolar cell invagination, both of which affected cone photoreceptor terminal synaptic activity, was identified by transmission electron microscopy and immunohistochemistry, respectively. Taken together, our results show that Fezf2 is indispensable in differentiation of bipolar precursors into cone OFF bipolar cells and in functional maturation of cone ON bipolar cells during development of mouse retina. These results contribute to our understanding of how diversity of neuronal subtypes and hence specificity of neuronal connections are established in the retina by intrinsic cues. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chromatic detection from cone photoreceptors to V1 neurons to behavior in rhesus monkeys.

Science.gov (United States)

Hass, Charles A; Angueyra, Juan M; Lindbloom-Brown, Zachary; Rieke, Fred; Horwitz, Gregory D

2015-01-01

Chromatic sensitivity cannot exceed limits set by noise in the cone photoreceptors. To determine how close neurophysiological and psychophysical chromatic sensitivity come to these limits, we developed a parameter-free model of stimulus encoding in the cone outer segments, and we compared the sensitivity of the model to the psychophysical sensitivity of monkeys performing a detection task and to the sensitivity of individual V1 neurons. Modeled cones had a temporal impulse response and a noise power spectrum that were derived from in vitro recordings of macaque cones, and V1 recordings were made during performance of the detection task. The sensitivity of the simulated cone mosaic, the V1 neurons, and the monkeys were tightly yoked for low-spatiotemporal-frequency isoluminant modulations, indicating high-fidelity signal transmission for this class of stimuli. Under the conditions of our experiments and the assumptions for our model, the signal-to-noise ratio for these stimuli dropped by a factor of ∼3 between the cones and perception. Populations of weakly correlated V1 neurons narrowly exceeded the monkeys' chromatic sensitivity but fell well short of the cones' chromatic sensitivity, suggesting that most of the behavior-limiting noise lies between the cone outer segments and the output of V1. The sensitivity gap between the cones and behavior for achromatic stimuli was larger than for chromatic stimuli, indicating greater postreceptoral noise. The cone mosaic model provides a means to compare visual sensitivity across disparate stimuli and to identify sources of noise that limit visual sensitivity.

Technical factors influencing cone packing density estimates in adaptive optics flood illuminated retinal images.

Directory of Open Access Journals (Sweden)

Marco Lombardo

Full Text Available PURPOSE: To investigate the influence of various technical factors on the variation of cone packing density estimates in adaptive optics flood illuminated retinal images. METHODS: Adaptive optics images of the photoreceptor mosaic were obtained in fifteen healthy subjects. The cone density and Voronoi diagrams were assessed in sampling windows of 320×320 µm, 160×160 µm and 64×64 µm at 1.5 degree temporal and superior eccentricity from the preferred locus of fixation (PRL. The technical factors that have been analyzed included the sampling window size, the corrected retinal magnification factor (RMFcorr, the conversion from radial to linear distance from the PRL, the displacement between the PRL and foveal center and the manual checking of cone identification algorithm. Bland-Altman analysis was used to assess the agreement between cone density estimated within the different sampling window conditions. RESULTS: The cone density declined with decreasing sampling area and data between areas of different size showed low agreement. A high agreement was found between sampling areas of the same size when comparing density calculated with or without using individual RMFcorr. The agreement between cone density measured at radial and linear distances from the PRL and between data referred to the PRL or the foveal center was moderate. The percentage of Voronoi tiles with hexagonal packing arrangement was comparable between sampling areas of different size. The boundary effect, presence of any retinal vessels, and the manual selection of cones missed by the automated identification algorithm were identified as the factors influencing variation of cone packing arrangements in Voronoi diagrams. CONCLUSIONS: The sampling window size is the main technical factor that influences variation of cone density. Clear identification of each cone in the image and the use of a large buffer zone are necessary to minimize factors influencing variation of Voronoi

The holographic entropy cone

Energy Technology Data Exchange (ETDEWEB)

Bao, Ning [Institute for Quantum Information and Matter, California Institute of Technology,Pasadena, CA 91125 (United States); Walter Burke Institute for Theoretical Physics, California Institute of Technology,452-48, Pasadena, CA 91125 (United States); Nezami, Sepehr [Stanford Institute for Theoretical Physics, Stanford University,Stanford, CA 94305 (United States); Ooguri, Hirosi [Walter Burke Institute for Theoretical Physics, California Institute of Technology,452-48, Pasadena, CA 91125 (United States); Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo,Kashiwa 277-8583 (Japan); Stoica, Bogdan [Walter Burke Institute for Theoretical Physics, California Institute of Technology,452-48, Pasadena, CA 91125 (United States); Sully, James [Theory Group, SLAC National Accelerator Laboratory, Stanford University,Menlo Park, CA 94025 (United States); Walter, Michael [Stanford Institute for Theoretical Physics, Stanford University,Stanford, CA 94305 (United States)

2015-09-21

We initiate a systematic enumeration and classification of entropy inequalities satisfied by the Ryu-Takayanagi formula for conformal field theory states with smooth holographic dual geometries. For 2, 3, and 4 regions, we prove that the strong subadditivity and the monogamy of mutual information give the complete set of inequalities. This is in contrast to the situation for generic quantum systems, where a complete set of entropy inequalities is not known for 4 or more regions. We also find an infinite new family of inequalities applicable to 5 or more regions. The set of all holographic entropy inequalities bounds the phase space of Ryu-Takayanagi entropies, defining the holographic entropy cone. We characterize this entropy cone by reducing geometries to minimal graph models that encode the possible cutting and gluing relations of minimal surfaces. We find that, for a fixed number of regions, there are only finitely many independent entropy inequalities. To establish new holographic entropy inequalities, we introduce a combinatorial proof technique that may also be of independent interest in Riemannian geometry and graph theory.

The holographic entropy cone

International Nuclear Information System (INIS)

Bao, Ning; Nezami, Sepehr; Ooguri, Hirosi; Stoica, Bogdan; Sully, James; Walter, Michael

2015-01-01

We initiate a systematic enumeration and classification of entropy inequalities satisfied by the Ryu-Takayanagi formula for conformal field theory states with smooth holographic dual geometries. For 2, 3, and 4 regions, we prove that the strong subadditivity and the monogamy of mutual information give the complete set of inequalities. This is in contrast to the situation for generic quantum systems, where a complete set of entropy inequalities is not known for 4 or more regions. We also find an infinite new family of inequalities applicable to 5 or more regions. The set of all holographic entropy inequalities bounds the phase space of Ryu-Takayanagi entropies, defining the holographic entropy cone. We characterize this entropy cone by reducing geometries to minimal graph models that encode the possible cutting and gluing relations of minimal surfaces. We find that, for a fixed number of regions, there are only finitely many independent entropy inequalities. To establish new holographic entropy inequalities, we introduce a combinatorial proof technique that may also be of independent interest in Riemannian geometry and graph theory.

Evaluation of calcium, magnesium, zinc, aluminum and manganese deposition in bones and CNS of rats fed calcium-deficient diets

International Nuclear Information System (INIS)

Yasui, Masayuki; Ota, Kiichiro; Sasajima, Kazuhisa; Iwata, Shiro.

1994-01-01

The long term intake of unbalanced mineral diets has been reported to be one of the pathogenetic factors of central nervous system (CNS) degeneration, and the unbalanced mineral distribution in the bones clinically is expressed as a metabolic bone disorder or deposition of neurotoxic minerals/metals. The unbalanced mineral or metal diets in animals provoke the unbalanced mineral distribution in bones and soft tissues. In this study, the calcium (Ca), magnesium (Mg), zinc (Zn), aluminum (Al) and manganese (Mn) contents in the CNS and the bones of rats maintained on unbalanced mineral diets were analyzed to investigate the roles of bone on CNS degeneration. Male Wistar rats were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. Al and Mn contents were determined in the frontal cortex, spinal cord, lumbar spine and femur using inductively coupled plasma emission spectrometry (ICP) for Ca, Mg and Zn, and neutron activation analysis (NAA) for Al and Mn. Intake of low Ca and Mg with added Al in rats led to the abnormal distribution of metals or minerals in the bones and in the CNS. These results illustrate that unbalanced mineral diets and metal-metal interactions may lead to the irregular deposition of Al and Mn in the bones and ultimately in the CNS, thus inducing CNS degeneration. (author)

An ice-cream cone model for coronal mass ejections

Science.gov (United States)

Xue, X. H.; Wang, C. B.; Dou, X. K.

2005-08-01

In this study, we use an ice-cream cone model to analyze the geometrical and kinematical properties of the coronal mass ejections (CMEs). Assuming that in the early phase CMEs propagate with near-constant speed and angular width, some useful properties of CMEs, namely the radial speed (v), the angular width (α), and the location at the heliosphere, can be obtained considering the geometrical shapes of a CME as an ice-cream cone. This model is improved by (1) using an ice-cream cone to show the near real configuration of a CME, (2) determining the radial speed via fitting the projected speeds calculated from the height-time relation in different azimuthal angles, (3) not only applying to halo CMEs but also applying to nonhalo CMEs.

Instantons on Calabi-Yau and hyper-Kähler cones

Science.gov (United States)

Geipel, Jakob C.; Sperling, Marcus

2017-10-01

The instanton equations on vector bundles over Calabi-Yau and hyper-Kähler cones can be reduced to matrix equations resembling Nahm's equations. We complement the discussion of Hermitian Yang-Mills (HYM) equations on Calabi-Yau cones, based on regular semi-simple elements, by a new set of (singular) boundary conditions which have a known instanton solution in one direction. This approach extends the classic results of Kronheimer by probing a relation between generalised Nahm's equations and nilpotent pairs/tuples. Moreover, we consider quaternionic instantons on hyper-Kähler cones over generic 3-Sasakian manifolds and study the HYM moduli spaces arising in this set-up, using the fact that their analysis can be traced back to the intersection of three Hermitian Yang-Mills conditions.

Development of a Full Ice-cream Cone Model for Halo Coronal Mass Ejections

Energy Technology Data Exchange (ETDEWEB)

Na, Hyeonock; Moon, Y.-J.; Lee, Harim, E-mail: nho0512@khu.ac.kr, E-mail: moonyj@khu.ac.kr [School of Space Research, Kyung Hee University, Yongin (Korea, Republic of)

2017-04-20

It is essential to determine three-dimensional parameters (e.g., radial speed, angular width, and source location) of coronal mass ejections (CMEs) for the space weather forecast. In this study, we investigate which cone type represents a halo CME morphology using 29 CMEs (12 Solar and Heliospheric Observatory (SOHO) /Large Angle and Spectrometric Coronagraph (LASCO) halo CMEs and 17 Solar Terrestrial Relations Observatory ( STEREO )/Sun–Earth Connection Coronal and Heliospheric Investigation COR2 halo CMEs) from 2010 December to 2011 June. These CMEs are identified as halo CMEs by one spacecraft ( SOHO or one of STEREO A and B ) and limb ones by the other spacecraft (One of STEREO A and B or SOHO ). From cone shape parameters of these CMEs, such as their front curvature, we find that the CME observational structures are much closer to a full ice-cream cone type than a shallow ice-cream cone type. Thus, we develop a full ice-cream cone model based on a new methodology that the full ice-cream cone consists of many flat cones with different heights and angular widths to estimate the three-dimensional parameters of the halo CMEs. This model is constructed by carrying out the following steps: (1) construct a cone for a given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, and (4) minimize the difference between the estimated projection speeds with the observed ones. By applying this model to 12 SOHO /LASCO halo CMEs, we find that 3D parameters from our method are similar to those from other stereoscopic methods (i.e., a triangulation method and a Graduated Cylindrical Shell model).

Development of a Full Ice-cream Cone Model for Halo Coronal Mass Ejections

International Nuclear Information System (INIS)

Na, Hyeonock; Moon, Y.-J.; Lee, Harim

2017-01-01

It is essential to determine three-dimensional parameters (e.g., radial speed, angular width, and source location) of coronal mass ejections (CMEs) for the space weather forecast. In this study, we investigate which cone type represents a halo CME morphology using 29 CMEs (12 Solar and Heliospheric Observatory (SOHO) /Large Angle and Spectrometric Coronagraph (LASCO) halo CMEs and 17 Solar Terrestrial Relations Observatory ( STEREO )/Sun–Earth Connection Coronal and Heliospheric Investigation COR2 halo CMEs) from 2010 December to 2011 June. These CMEs are identified as halo CMEs by one spacecraft ( SOHO or one of STEREO A and B ) and limb ones by the other spacecraft (One of STEREO A and B or SOHO ). From cone shape parameters of these CMEs, such as their front curvature, we find that the CME observational structures are much closer to a full ice-cream cone type than a shallow ice-cream cone type. Thus, we develop a full ice-cream cone model based on a new methodology that the full ice-cream cone consists of many flat cones with different heights and angular widths to estimate the three-dimensional parameters of the halo CMEs. This model is constructed by carrying out the following steps: (1) construct a cone for a given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, and (4) minimize the difference between the estimated projection speeds with the observed ones. By applying this model to 12 SOHO /LASCO halo CMEs, we find that 3D parameters from our method are similar to those from other stereoscopic methods (i.e., a triangulation method and a Graduated Cylindrical Shell model).

Development of a Full Ice-cream Cone Model for Halo Coronal Mass Ejections

Science.gov (United States)

Na, Hyeonock; Moon, Y.-J.; Lee, Harim

2017-04-01

It is essential to determine three-dimensional parameters (e.g., radial speed, angular width, and source location) of coronal mass ejections (CMEs) for the space weather forecast. In this study, we investigate which cone type represents a halo CME morphology using 29 CMEs (12 Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO) halo CMEs and 17 Solar Terrestrial Relations Observatory (STEREO)/Sun-Earth Connection Coronal and Heliospheric Investigation COR2 halo CMEs) from 2010 December to 2011 June. These CMEs are identified as halo CMEs by one spacecraft (SOHO or one of STEREO A and B) and limb ones by the other spacecraft (One of STEREO A and B or SOHO). From cone shape parameters of these CMEs, such as their front curvature, we find that the CME observational structures are much closer to a full ice-cream cone type than a shallow ice-cream cone type. Thus, we develop a full ice-cream cone model based on a new methodology that the full ice-cream cone consists of many flat cones with different heights and angular widths to estimate the three-dimensional parameters of the halo CMEs. This model is constructed by carrying out the following steps: (1) construct a cone for a given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, and (4) minimize the difference between the estimated projection speeds with the observed ones. By applying this model to 12 SOHO/LASCO halo CMEs, we find that 3D parameters from our method are similar to those from other stereoscopic methods (I.e., a triangulation method and a Graduated Cylindrical Shell model).

Holographic entanglement entropy for hollow cones and banana shaped regions

Energy Technology Data Exchange (ETDEWEB)

Dorn, Harald [Institut für Physik und IRIS Adlershof, Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, D-12489 Berlin (Germany)

2016-06-09

We consider banana shaped regions as examples of compact regions, whose boundary has two conical singularities. Their regularised holographic entropy is calculated with all divergent as well as finite terms. The coefficient of the squared logarithmic divergence, also in such a case with internally curved boundary, agrees with that calculated in the literature for infinite circular cones with their internally flat boundary. For the otherwise conformally invariant coefficient of the ordinary logarithmic divergence an anomaly under exceptional conformal transformations is observed. The construction of minimal submanifolds, needed for the entanglement entropy of cones, requires fine-tuning of Cauchy data. Perturbations of such fine-tuning leads to solutions relevant for hollow cones. The divergent parts for the entanglement entropy of hollow cones are calculated. Increasing the difference between the opening angles of their outer and inner boundary, one finds a transition between connected solutions for small differences to disconnected solutions for larger ones.

Poisson-type inequalities for growth properties of positive superharmonic functions.

Science.gov (United States)

Luan, Kuan; Vieira, John

2017-01-01

In this paper, we present new Poisson-type inequalities for Poisson integrals with continuous data on the boundary. The obtained inequalities are used to obtain growth properties at infinity of positive superharmonic functions in a smooth cone.

CARR-CNS with crescent-shape moderator cell and sub-cooling helium jacket surrounding cell

International Nuclear Information System (INIS)

Yu, Qingfeng; Feng, Quanke; Kawai, Takeshi; Shen, Feng; Yuan, Luzheng

2005-01-01

The new type of the moderator cell was developed for the Cold Neutron Source (CNS) of the China Advanced Research Reactor (CARR) which is now constructing at the China Institute of Atomic Energy in Beijing. A crescent-shape moderator cell covered by the sub-cooling helium jacket is adopted. A crescent-shape would help to increase the volume of the moderator cell for corresponding it to the 4 cold neutron guide tubes, even if liquid hydrogen not liquid deuterium were used as a cold moderator. The sub-cooling helium jacket covering the moderator cell removes the nuclear heating of the outer shell wall of the cell. It contributes to reduce the void fraction of liquid hydrogen in the inner shell. Such a type of a moderator cell is suitable for the CNS with higher nuclear heating. The cold helium gas flows down firstly into the sub-cooling helium jacket and then flows up to the condenser. Therefore, the theory of the self-regulation for the thermo-siphon type of the CNS is also applicable

CARR-CNS with crescent-shape moderator cell and sub-cooling helium jacket around cell

International Nuclear Information System (INIS)

Yu, Qingfeng; Feng, Quanke; Kawai, Takeshi; Cheng, Liang; Shen, Feng; Yuan, Luzheng

2005-01-01

The new type of the moderator cell was developed for the Cold Neutron Source (CNS) of the China Advanced Research Reactor (CARR) which is now constructing at the China Institute of Atomic Energy in Beijing. A crescent-shape moderator cell covered by the sub-cooling helium jacket is adopted. A crescent-shape would help to increase the volume of the moderator cell for corresponding it to the 4 cold neutron guide tubes, even if liquid hydrogen not liquid deuterium were used as a cold moderator. The sub-cooling helium jacket covering the moderator cell removes the nuclear heating of the outer shell wall of the cell. It contributes to reduce the void fraction of liquid hydrogen in the inner shell. Such a type of a moderator cell is suitable for the CNS with higher nuclear heating. The cold helium gas flows down firstly into the sub-cooling helium jacket and then flows up to the condenser. Therefore, the theory of the self-regulation for the thermo-siphon type of the CNS is also applicable

Distribution of CNS Species on Teat Skin and in Milk Samples from Dairy Cows in Automatic Milking Systems

DEFF Research Database (Denmark)

Mahmmod, Yasser; Svennesen, Line; Pedersen, Karl

identified in milk samples. Staphylococcus chromogenes was detected in both milk (n= 2) and teat skin (n= 1) samples. Data collection will be finished in April 2017. The final results will give new insights into herd specific CNS species patterns and the microbial ecology and epidemiology of common CNS...

A Fat-Facets-Dscam1-JNK Pathway Enhances Axonal Growth in Development and after Injury

Directory of Open Access Journals (Sweden)

Marta Koch

2018-02-01

Full Text Available Injury to the adult central nervous systems (CNS can result in severe long-term disability because damaged CNS connections fail to regenerate after trauma. Identification of regulators that enhance the intrinsic growth capacity of severed axons is a first step to restore function. Here, we conducted a gain-of-function genetic screen in Drosophila to identify strong inducers of axonal growth after injury. We focus on a novel axis the Down Syndrome Cell Adhesion Molecule (Dscam1, the de-ubiquitinating enzyme Fat Facets (Faf/Usp9x and the Jun N-Terminal Kinase (JNK pathway transcription factor Kayak (Kay/Fos. Genetic and biochemical analyses link these genes in a common signaling pathway whereby Faf stabilizes Dscam1 protein levels, by acting on the 3′-UTR of its mRNA, and Dscam1 acts upstream of the growth-promoting JNK signal. The mammalian homolog of Faf, Usp9x/FAM, shares both the regenerative and Dscam1 stabilizing activities, suggesting a conserved mechanism.

Mer tyrosine kinase promotes the survival of t(1;19)-positive acute lymphoblastic leukemia (ALL) in the central nervous system (CNS).

Science.gov (United States)

Krause, Sarah; Pfeiffer, Christian; Strube, Susanne; Alsadeq, Ameera; Fedders, Henning; Vokuhl, Christian; Loges, Sonja; Waizenegger, Jonas; Ben-Batalla, Isabel; Cario, Gunnar; Möricke, Anja; Stanulla, Martin; Schrappe, Martin; Schewe, Denis M

2015-01-29

Patients with t(1;19)-positive acute lymphoblastic leukemia (ALL) are prone to central nervous system (CNS) relapses, and expression of the TAM (Tyro3, Axl, and Mer) receptor Mer is upregulated in these leukemias. We examined the functional role of Mer in the CNS in preclinical models and performed correlative studies in 64 t(1;19)-positive and 93 control pediatric ALL patients. ALL cells were analyzed in coculture with human glioma cells and normal rat astrocytes: CNS coculture caused quiescence and protection from methotrexate toxicity in Mer(high) ALL cell lines, which was antagonized by short hairpin RNA-mediated knockdown of Mer. Mer expression was upregulated, prosurvival Akt and mitogen-activated protein kinase signaling were activated, and secretion of the Mer ligand Galectin-3 was stimulated. Mer(high) t(1;19) primary cells caused CNS involvement to a larger extent in murine xenografts than in their Mer(low) counterparts. Leukemic cells from Mer(high) xenografts showed enhanced survival in coculture. Treatment of Mer(high) patient cells with the Mer-specific inhibitor UNC-569 in vivo delayed leukemia onset, reduced CNS infiltration, and prolonged survival of mice. Finally, a correlation between high Mer expression and CNS positivity upon initial diagnosis was observed in t(1;19) patients. Our data provide evidence that Mer is associated with survival in the CNS in t(1;19)-positive ALL, suggesting a role as a diagnostic marker and therapeutic target. © 2015 by The American Society of Hematology.

Development of a cone-geometry positron moderator

International Nuclear Information System (INIS)

Lynn, K.G.; Gramsch, E.; Usmar, S.G.; Sferlazzo, P.

1989-01-01

Results are presented on a new cone-shaped positron moderator which shows a high moderator efficiency (i.e., conversion of beta decay to emitted slow positrons). The moderator efficiencies for the cone moderators studied were found to be up to 0.14% compared to thin-foil measurements of 0.06% in the same experimental system including identical source and holder. These moderators are rugged and easily fabricated, however, they have a lower brightness than single-crystal foil moderators. Comparison of various geometries is presented as well as suggestions for further improvements to increase the total efficiencies

Some Nonunique Fixed Point Theorems of Ćirić Type on Cone Metric Spaces

Directory of Open Access Journals (Sweden)

Erdal Karapınar

2010-01-01

Full Text Available Some results of (Ćirić, 1974 on a nonunique fixed point theorem on the class of metric spaces are extended to the class of cone metric spaces. Namely, nonunique fixed point theorem is proved in orbitally complete cone metric spaces under the assumption that the cone is strongly minihedral. Regarding the scalar weight of cone metric, we are able to remove the assumption of strongly minihedral.

Utility of FDG-PETCT and magnetic resonance spectroscopy in differentiating between cerebral lymphoma and non-malignant CNS lesions in HIV-infected patients

Energy Technology Data Exchange (ETDEWEB)

Westwood, Thomas D., E-mail: tdwestwood@googlemail.com [Department of Radiology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Hogan, Celia, E-mail: celiahogan@hotmail.com [Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital, Pennine Acute Hospitals NHS Trust (United Kingdom); Julyan, Peter J., E-mail: Peter.Julyan@christie.nhs.uk [Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Coutts, Glyn, E-mail: Glyn.Coutts@christie.nhs.uk [Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Bonington, Suzie, E-mail: suzi.bonington@christie.nhs.uk [Department of Radiology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Carrington, Bernadette, E-mail: Bernadette.Carrington@christie.nhs.uk [Department of Radiology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Taylor, Ben, E-mail: Ben.taylor@christie.nhs.uk [Department of Radiology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester (United Kingdom); Khoo, Saye, E-mail: S.H.Khoo@liverpool.ac.uk [Department of Infectious Diseases and Tropical Medicine, Royal Liverpool Hospital, Liverpool (United Kingdom); Bonington, Alec, E-mail: Alec.Bonington@pat.nhs.uk [Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital, Pennine Acute Hospitals NHS Trust (United Kingdom)

2013-08-15

Background and purpose: In HIV infected patients, MRI cannot reliably differentiate between central nervous system (CNS) lymphoma and non-malignant CNS lesions, particularly cerebral toxoplasmosis (CTOX). This study prospectively investigates the utility of FDG PET-CT and magnetic resonance spectroscopy (MRS) in discriminating CNS lymphoma from non-malignant CNS lesions in HIV infected patients, and assesses the ability of FDG PET-CT to guide the use of early brain biopsy. Methods: 10 HIV patients with neurological symptoms and contrast enhancing lesions on MRI were commenced on anti-toxoplasmosis therapy before undergoing FDG PET-CT and MRS. Brain biopsies were sought in those with FDG PET-CT suggestive of CNS lymphoma, and in those with a negative FDG PET-CT scan who failed to respond to therapy. Final diagnosis was based on histology or treatment response. Results: Two patients were confirmed to have CNS lymphoma and FDG PET-CT was consistent with this diagnosis in both. Six patients had cerebral toxoplasmosis in all of whom FDG PET-CT was consistent with non-malignant disease. One patient had progressive multifocal leukoencephalopathy (PML), FDG PET-CT was equivocal. One patient had a haemorrhagic brain metastasis and FDG PET-CT wrongly suggested non-malignant disease. MRS was performed successfully in eight subjects: three results were suggestive of CNS lymphoma (one true positive, two false positive), four suggested CTOX (two false negative, two true negative), one scan was equivocal. Conclusion: FDG PET-CT correctly identified all cases of CNS lymphoma and CTOX, supporting its use in this situation. MRS was unhelpful in our cohort.

Utility of FDG-PETCT and magnetic resonance spectroscopy in differentiating between cerebral lymphoma and non-malignant CNS lesions in HIV-infected patients

International Nuclear Information System (INIS)

Westwood, Thomas D.; Hogan, Celia; Julyan, Peter J.; Coutts, Glyn; Bonington, Suzie; Carrington, Bernadette; Taylor, Ben; Khoo, Saye; Bonington, Alec

2013-01-01

Background and purpose: In HIV infected patients, MRI cannot reliably differentiate between central nervous system (CNS) lymphoma and non-malignant CNS lesions, particularly cerebral toxoplasmosis (CTOX). This study prospectively investigates the utility of FDG PET-CT and magnetic resonance spectroscopy (MRS) in discriminating CNS lymphoma from non-malignant CNS lesions in HIV infected patients, and assesses the ability of FDG PET-CT to guide the use of early brain biopsy. Methods: 10 HIV patients with neurological symptoms and contrast enhancing lesions on MRI were commenced on anti-toxoplasmosis therapy before undergoing FDG PET-CT and MRS. Brain biopsies were sought in those with FDG PET-CT suggestive of CNS lymphoma, and in those with a negative FDG PET-CT scan who failed to respond to therapy. Final diagnosis was based on histology or treatment response. Results: Two patients were confirmed to have CNS lymphoma and FDG PET-CT was consistent with this diagnosis in both. Six patients had cerebral toxoplasmosis in all of whom FDG PET-CT was consistent with non-malignant disease. One patient had progressive multifocal leukoencephalopathy (PML), FDG PET-CT was equivocal. One patient had a haemorrhagic brain metastasis and FDG PET-CT wrongly suggested non-malignant disease. MRS was performed successfully in eight subjects: three results were suggestive of CNS lymphoma (one true positive, two false positive), four suggested CTOX (two false negative, two true negative), one scan was equivocal. Conclusion: FDG PET-CT correctly identified all cases of CNS lymphoma and CTOX, supporting its use in this situation. MRS was unhelpful in our cohort

Depolarization and electrical stimulation enhance in vitro and in vivo sensory axon growth after spinal cord injury.

Science.gov (United States)

Goganau, Ioana; Sandner, Beatrice; Weidner, Norbert; Fouad, Karim; Blesch, Armin

2018-02-01

Activity dependent plasticity is a key mechanism for the central nervous system (CNS) to adapt to its environment. Whether neuronal activity also influences axonal regeneration in the injured CNS, and whether electrical stimulation (ES) can activate regenerative programs in the injured CNS remains incompletely understood. Using KCl-induced depolarization, in vivo ES followed by ex-vivo neurite growth assays and ES after spinal cord lesions and cell grafting, we aimed to identify parameters important for ES-enhanced neurite growth and axonal regeneration. Using cultures of sensory neurons, neurite growth was analyzed after KCl-induced depolarization for 1-72h. Increased neurite growth was detected after short-term stimulation and after longer stimulation if a sufficient delay between stimulation and growth measurements was provided. After in vivo ES (20Hz, 2× motor threshold, 0.2ms, 1h) of the intact sciatic nerve in adult Fischer344 rats, sensory neurons showed a 2-fold increase in in vitro neurite length one week later compared to sham animals, an effect not observed one day after ES. Longer ES (7h) and repeated ES (7days, 1h each) also increased growth by 56-67% one week later, but provided no additional benefit. In vivo growth of dorsal column sensory axons into a graft of bone marrow stromal cells 4weeks after a cervical spinal cord lesion was also enhanced with a single post-injury 1h ES of the intact sciatic nerve and was also observed after repeated ES without inducing pain-like behavior. While ES did not result in sensory functional recovery, our data indicate that ES has time-dependent influences on the regenerative capacity of sensory neurons and might further enhance axonal regeneration in combinatorial approaches after SCI. Copyright © 2017 Elsevier Inc. All rights reserved.

Insectos de cones y semillas de las coniferas de Mexico

Science.gov (United States)

David Cibrián-Tovar; Bernard H. Ebel; Harry O. Yates; José Tulio Mhdez-Montiel

1986-01-01

The hosts, description, damage, life cycle, habits, and importance of 54 known cone and seed destroying insects attacking Mexican conifer trees are discussed. Distribution maps and color photos are provided. New species described are three species of Cydia (seedworm), four species of Dioryctria (coneworm), and four species of cone...

Ejecta evolution during cone impact

KAUST Repository

Marston, Jeremy; Thoroddsen, Sigurdur T

2014-01-01

-similarity for all impact speeds for very low surface tension liquids, whilst for high-surface tension liquids similarity is only achieved at high impact speeds. We find that the ejecta tip can detach from the cone and that this phenomenon can be attributed

Developmental hyperoxia alters CNS mechanisms underlying hypoxic ventilatory depression in neonatal rats.

Science.gov (United States)

Hill, Corey B; Grandgeorge, Samuel H; Bavis, Ryan W

2013-12-01

Newborn mammals exhibit a biphasic hypoxic ventilatory response (HVR), but the relative contributions of carotid body-initiated CNS mechanisms versus central hypoxia on ventilatory depression during the late phase of the HVR are not well understood. Neonatal rats (P4-5 or P13-15) were treated with a nonselective P2 purinergic receptor antagonist (pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid, or PPADS; 125mgkg(-1), i.p.) to pharmacologically denervate the peripheral chemoreceptors. At P4-5, rats reared in normoxia showed a progressive decline in ventilation during a 10-min exposure to 12% O2 (21-28% decrease from baseline). No hypoxic ventilatory depression was observed in the older group of neonatal rats (i.e., P13-15), suggesting that the contribution of central hypoxia to hypoxic ventilatory depression diminishes with age. In contrast, rats reared in moderate hyperoxia (60% O2) from birth exhibited no hypoxic ventilatory depression at either age studied. Systemic PPADS had no effect on the ventilatory response to 7% CO2, suggesting that the drug did not cross the blood-brain barrier. These findings indicate that (1) CNS hypoxia depresses ventilation in young, neonatal rats independent of carotid body activation and (2) hyperoxia alters the development of CNS pathways that modulate the late phase of the hypoxic ventilatory response. Copyright © 2013 Elsevier B.V. All rights reserved.

Receptivity of Hypersonic Boundary Layers over Straight and Flared Cones

Science.gov (United States)

Balakumar, Ponnampalam; Kegerise, Michael A.

2010-01-01

The effects of adverse pressure gradients on the receptivity and stability of hypersonic boundary layers were numerically investigated. Simulations were performed for boundary layer flows over a straight cone and two flared cones. The steady and the unsteady flow fields were obtained by solving the two-dimensional Navier-Stokes equations in axi-symmetric coordinates using the 5th order accurate weighted essentially non-oscillatory (WENO) scheme for space discretization and using third-order total-variation-diminishing (TVD) Runge-Kutta scheme for time integration. The mean boundary layer profiles were analyzed using local stability and non-local parabolized stability equations (PSE) methods. After the most amplified disturbances were identified, two-dimensional plane acoustic waves were introduced at the outer boundary of the computational domain and time accurate simulations were performed. The adverse pressure gradient was found to affect the boundary layer stability in two important ways. Firstly, the frequency of the most amplified second-mode disturbance was increased relative to the zero pressure gradient case. Secondly, the amplification of first- and second-mode disturbances was increased. Although an adverse pressure gradient enhances instability wave growth rates, small nose-tip bluntness was found to delay transition due to the low receptivity coefficient and the resulting weak initial amplitude of the instability waves. The computed and measured amplitude-frequency spectrums in all three cases agree very well in terms of frequency and the shape except for the amplitude.

Discrimination of different brain metastases and primary CNS lymphomas using morphologic criteria and diffusion tensor imaging

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Bette, S.; Wiestler, B.; Huber, T.; Boeckh-Behrens, T.; Zimmer, C.; Kirschke, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuroradiology; Delbridge, C. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuropathology; Meyer, B.; Gempt, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neurosurgery

2016-12-15

Brain metastases are a common complication of cancer and occur in about 15-40% of patients with malignancies. The aim of this retrospective study was to differentiate between metastases from different primary tumors/CNS lymphyomas using morphologic criteria, fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Morphologic criteria such as hemorrhage, cysts, pattern of contrast enhancement and location were reported in 200 consecutive patients with brain metastases/primary CNS lymphomas. FA and ADC values were measured in regions of interest (ROIs) placed in the contrast-enhancing tumor part, the necrosis and the non-enhancing peritumoral region (NEPTR). Differences between histopathological subtypes of metastases were analyzed using non-parametric tests, decision trees and hierarchical clustering analysis. Significant differences were found in morphologic criteria such as hemorrhage or pattern of contrast enhancement. In diffusion measurements, significant differences between the different tumor entities were only found in ADC analyzed in the contrast-enhancing tumor part. Among single tumor entities, primary CNS lymphomas showed significantly lower median ADC values in the contrast-enhancing tumor part (ADC{sub lymphoma} 0.92 [0.83-1.07] vs. ADC{sub no} {sub lymphoma} 1.35 [1.10-1.64] P=0.001). Further differentiation between types of metastases was not possible using FA and ADC. There were morphologic differences among the main subtypes of brain metastases/CNS lymphomas. However, due to a high variability of common types of metastases and low specificity, prospective differentiation remained challenging. DTI including FA and ADC was not a reliable tool for differentiation between different histopathological subtypes of brain metastases except for CNS lymphomas showing lower ADC values. Biopsy, surgery and staging remain essential for diagnosis.

Effects on DHEA levels by estrogen in rat astrocytes and CNS co-cultures via the regulation of CYP7B1-mediated metabolism

DEFF Research Database (Denmark)

Fex Svenningsen, Åsa; Wicher, Grzegorz; Lundqvist, Johan

2011-01-01

The neurosteroid dehydroepiandrosterone (DHEA) is formed locally in the CNS and has been implicated in several processes essential for CNS function, including control of neuronal survival. An important metabolic pathway for DHEA in the CNS involves the steroid hydroxylase CYP7B1. In previous...... studies, CYP7B1 was identified as a target for estrogen regulation in cells of kidney and liver. In the current study, we examined effects of estrogens on CYP7B1-mediated metabolism of DHEA in primary cultures of rat astrocytes and co-cultures of rat CNS cells. Astrocytes, which interact with neurons...... whereby estrogen can exert protective effects in the CNS may involve increase of the levels of DHEA by suppression of its metabolism....

Cone photopigment in older subjects: decreased optical density in early age-related macular degeneration

Science.gov (United States)

Elsner, Ann E.; Burns, Stephen A.; Weiter, John J.

2002-01-01

We measured changes to cone photoreceptors in patients with early age-related macular degeneration. The data of 53 patients were compared with normative data for color matching measurements of long- and middle-wavelength-sensitive cones in the central macula. A four-parameter model quantified cone photopigment optical density and kinetics. Cone photopigment optical density was on average less for the patients than for normal subjects and was uncorrelated with visual acuity. More light was needed to reduce the photopigment density by 50% in the steady state for patients. These results imply that cone photopigment optical density is reduced by factors other than slowed kinetics.

Comparative antibiogram of coagulase-negative Staphylococci (CNS) associated with subclinical and clinical mastitis in dairy cows.

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Bansal, B K; Gupta, D K; Shafi, T A; Sharma, S

2015-03-01

The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS) strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17). Isolates were highly susceptible to chloramphenicol (98.3%), gentamicin (93.1%), streptomycin (91.4%), linezolid (91.4%), ceftixozime (87.9%), cloxacillin (86.2%), clotrimazole (86.2%), bacitracin (86.2%), enrofloxacin (84.5%) and ceftrioxone + tazobactum (70.7%), while resistance was observed against amoxicillin (77.6%), penicillin (75.9%), ampicillin (74.1%) and cefoperazone (51.7%). Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.

On Krasnoselskii's Cone Fixed Point Theorem

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Man Kam Kwong

2008-04-01

Full Text Available In recent years, the Krasnoselskii fixed point theorem for cone maps and its many generalizations have been successfully applied to establish the existence of multiple solutions in the study of boundary value problems of various types. In the first part of this paper, we revisit the Krasnoselskii theorem, in a more topological perspective, and show that it can be deduced in an elementary way from the classical Brouwer-Schauder theorem. This viewpoint also leads to a topology-theoretic generalization of the theorem. In the second part of the paper, we extend the cone theorem in a different direction using the notion of retraction and show that a stronger form of the often cited Leggett-Williams theorem is a special case of this extension.

Nontraumatic tibial polyethylene insert cone fracture in mobile-bearing posterior-stabilized total knee arthroplasty

OpenAIRE

Tanikake, Yohei; Hayashi, Koji; Ogawa, Munehiro; Inagaki, Yusuke; Kawate, Kenji; Tomita, Tetsuya; Tanaka, Yasuhito

2016-01-01

A 72-year-old male patient underwent mobile-bearing posterior-stabilized total knee arthroplasty for osteoarthritis. He experienced a nontraumatic polyethylene tibial insert cone fracture 27 months after surgery. Scanning electron microscopy of the fracture surface of the tibial insert cone suggested progress of ductile breaking from the posterior toward the anterior of the cone due to repeated longitudinal bending stress, leading to fatigue breaking at the anterior side of the cone, followed...

The DAL10 gene from Norway spruce (Picea abies) belongs to a potentially gymnosperm-specific subclass of MADS-box genes and is specifically active in seed cones and pollen cones.

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Carlsbecker, Annelie; Sundström, Jens; Tandre, Karolina; Englund, Marie; Kvarnheden, Anders; Johanson, Urban; Engström, Peter

2003-01-01

Transcription factors encoded by different members of the MADS-box gene family have evolved central roles in the regulation of reproductive organ development in the flowering plants, the angiosperms. Development of the stamens and carpels, the pollen- and seed-bearing organs, involves the B- and C-organ-identity MADS-box genes. B- and C-type gene orthologs with activities specifically in developing pollen- and seed-bearing organs are also present in the distantly related gymnosperms: the conifers and the gnetophytes. We now report on the characterization of DAL10, a novel MADS-box gene from the conifer Norway spruce, which unlike the B- and C-type conifer genes shows no distinct orthology relationship to any angiosperm gene or clade in phylogenetic analyses. Like the B- and C-type genes, it is active specifically in developing pollen cones and seed cones. In situ RNA localization experiments show DAL10 to be expressed in the cone axis, which carry the microsporophylls of the young pollen cone. In contrast, in the seed cone it is expressed both in the cone axis and in the bracts, which subtend the ovuliferous scales. Expression data and the phenotype of transgenic Arabidopsis plants expressing DAL10 suggest that the gene may act upstream to or in concert with the B- and C-type genes in the establishment of reproductive identity of developing cones.

Glibenclamide for the Treatment of Acute CNS Injury

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J. Marc Simard

2013-10-01

Full Text Available First introduced into clinical practice in 1969, glibenclamide (US adopted name, glyburide is known best for its use in the treatment of diabetes mellitus type 2, where it is used to promote the release of insulin by blocking pancreatic KATP [sulfonylurea receptor 1 (Sur1-Kir6.2] channels. During the last decade, glibenclamide has received renewed attention due to its pleiotropic protective effects in acute CNS injury. Acting via inhibition of the recently characterized Sur1-Trpm4 channel (formerly, the Sur1-regulated NCCa-ATP channel and, in some cases, via brain KATP channels, glibenclamide has been shown to be beneficial in several clinically relevant rodent models of ischemic and hemorrhagic stroke, traumatic brain injury, spinal cord injury, neonatal encephalopathy of prematurity, and metastatic brain tumor. Glibenclamide acts on microvessels to reduce edema formation and secondary hemorrhage, it inhibits necrotic cell death, it exerts potent anti-inflammatory effects and it promotes neurogenesis—all via inhibition of Sur1. Two clinical trials, one in TBI and one in stroke, currently are underway. These recent findings, which implicate Sur1 in a number of acute pathological conditions involving the CNS, present new opportunities to use glibenclamide, a well-known, safe pharmaceutical agent, for medical conditions that heretofore had few or no treatment options.

Wavelet Cross-Spectrum Analysis of Multi-Scale Disturbance Instability and Transition on Sharp Cone Hypersonic Boundary Layer

International Nuclear Information System (INIS)

Jian, Han; Nan, Jiang

2008-01-01

Experimental measurement of hypersonic boundary layer stability and transition on a sharp cone with a half angle of 5° is carried out at free-coming stream Mach number 6 in a hypersonic wind tunnel. Mean and fluctuation surface-thermal-flux characteristics of the hypersonic boundary layer flow are measured by Pt-thin-film thermocouple temperature sensors installed at 28 stations on the cone surface along longitudinal direction. At hypersonic speeds, the dominant flow instabilities demonstrate that the growth rate of the second mode tends to exceed that of the low-frequency mode. Wavelet-based cross-spectrum technique is introduced to obtain the multi-scale cross-spectral characteristics of the fluctuating signals in the frequency range of the second mode. Nonlinear interactions both of the second mode disturbance and the first mode disturbance are demonstrated to be dominant instabilities in the initial stage of laminar-turbulence transition for hypersonic shear flow. (fundamental areas of phenomenology (including applications))

Lentiviral-mediated administration of IL-25 in the CNS induces alternative activation of microglia

DEFF Research Database (Denmark)

Maiorino, C; Khorooshi, R; Ruffini, F

2013-01-01

Interleukin-25 (IL-25) is the only anti-inflammatory cytokine of the IL-17 family, and it has been shown to be efficacious in inhibiting neuroinflammation. Known for its effects on cells of the adaptive immune system, it has been more recently described to be effective also on cells of the innate...... was partly inhibited and the CNS protected from immune-mediated damage. To our knowledge, this is the first example of M2 shift (alternative activation) induced in vivo on CNS-resident myeloid cells by gene therapy, and may constitute a promising strategy to investigate the potential role of protective...

Monte-Carlo Simulation of Hydrogen Adsorption in Single-Wall Carbon Nano-Cones

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Zohreh Ahadi

2011-01-01

Full Text Available The properties of hydrogen adsorption in single-walled carbon nano-cones are investigated in detail by Monte Carlo simulations. A great deal of our computational results show that the hydrogen storage capacity in single-walled carbon nano-cones is slightly smaller than the capacity of single-walled carbon nanotubes at any time at the same conditions. This indicates that the hydrogen storage capacity of single-walled carbon nano-cones is related to angles of carbon nano-cones. It seems that these type of nanotubes could not exceed the 2010 goal of 6 wt%, which is presented by the U.S. Department of Energy. In addition, these results are discussed in theory.

Early wound site seeding in a patient with CNS high-grade neuroepithelial tumor with BCOR alteration: A case report.

Science.gov (United States)

Kirkman, Matthew A; Pickles, Jessica C; Fairchild, Amy R; Avery, Aimee; Pietsch, Torsten; Jacques, Thomas S; Aquilina, Kristian

2018-05-30

Advances in molecular profiling have facilitated the emergence of newly defined entities of central nervous system tumor, including CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR). Relatively little is known about the clinical behaviour of these newly-characterized tumors. We describe a pediatric male patient with CNS HGNET-BCOR who developed seeding of the tumor into the site of the surgical wound within months of surgery for resection of a residual posterior fossa tumor. This case emphasises three important points. First, CNS HGNET-BCOR can be aggressive tumors that necessitate close clinical and radiological surveillance. Second, surveillance imaging in such cases should incorporate the surgical incision site into the field of view, and this should be closely scrutinised to ensure the timely detection of wound site seeding. Third, wound site seeding may still occur despite the use of meticulous surgical techniques. Copyright © 2018. Published by Elsevier Inc.

Fixed Points of α-Admissible Mappings in Cone Metric Spaces with Banach Algebra

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S.K. Malhotra

2015-11-01

Full Text Available In this paper, we introduce the $\\alpha$-admissible mappings in the setting of cone metric spaces equipped with Banach algebra and solid cones. Our results generalize and extend several known results of metric and cone metric spaces. An example is presented which illustrates and shows the significance of results proved herein.

Improved image quality for asymmetric double-focal cone-beam SPECT

International Nuclear Information System (INIS)

Cao, Z.J.; Tsui, B.M.W.

1993-01-01

To optimize both spatial resolution and detection efficiency in brain SPECT imaging using a rectangular camera, an asymmetric double-focal cone-beam collimator is proposed with the focal points located near the base plane of the patient's head. To fit the entire head into the field-of-view of the collimator with dimensions of 50cmx40cm and at a radius-of-rotation of 15 cm, the focal lengths of the collimator are 55 and 70 cm, respectively, in the transverse and axial directions. With this geometry, the artifacts in the reconstructed image produced by the Feldkamp algorithm are more severe compared to those in a symmetric cone-beam geometry, due to the larger vertex angle between the top of the head and the base plane. To improve the reconstructed image quality, a fully three-dimensional (3D) reconstruction algorithm developed previously for single-focal cone-beam SPECT was extended to the asymmetric double-focal cone-beam geometry. The algorithm involves nonstationary 2D filtering and a reprojection technique for estimation of the missing data caused by a single-orbit cone-beam geometry. The results from simulation studies with the 3D Defrise slab phantom demonstrated that the fully 3D algorithm provided a much improved image quality in terms of reduced slice-to-slice cross talks and shape elongation compared to that produced by the conventional Feldkamp algorithm

The photocurrent response of human cones is fast and monophasic

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Lamb TD

2006-04-01

Full Text Available Abstract Background The precise form of the light response of human cone photoreceptors in vivo has not been established with certainty. To investigate the response shape we compare the predictions of a recent model of transduction in primate cone photoreceptors with measurements extracted from human cones using the paired-flash electroretinogram method. As a check, we also compare the predictions with previous single-cell measurements of ground squirrel cone responses. Results The predictions of the model provide a good description of the measurements, using values of parameters within the range previously determined for primate retina. The dim-flash response peaks in about 20 ms, and flash responses at all intensities are essentially monophasic. Three time constants in the model are extremely short: the two time constants for inactivation (of visual pigment and of transducin/phosphodiesterase are around 3 and 10 ms, and the time constant for calcium equilibration lies in the same range. Conclusion The close correspondence between experiment and theory, using parameters previously derived for recordings from macaque retina, supports the notion that the electroretinogram approach and the modelling approach both provide an accurate estimate of the cone photoresponse in the living human eye. For reasons that remain unclear, the responses of isolated photoreceptors from the macaque retina, recorded previously using the suction pipette method, are considerably slower than found here, and display biphasic kinetics.

Micropituitarism and cortical dysplasia: an unknown association of two uncommon CNS disorders

International Nuclear Information System (INIS)

Blinder, G.; Corat-Simon, J.; Hershkovitz, E.

2001-01-01

We describe a case of two known pathologies of the CNS in an unusual association: the concomitant presentation of the micropituitarism and cortical dysplasia. To our knowledge, this association is unreported to date. (orig.)

Micropituitarism and cortical dysplasia: an unknown association of two uncommon CNS disorders

Energy Technology Data Exchange (ETDEWEB)

Blinder, G. [MAR Bikur Cholim Hospital Jerusalem (MOR-MAR), Jerusalem (Israel); Corat-Simon, J. [Dept. of Radiology, Assaf Harofeh Medical Center, Zrifin, Beer Jakov (Israel); Hershkovitz, E. [Dept. of Pediatrics, Soroka Medical Center, Beer Sheba (Israel)

2001-06-01

We describe a case of two known pathologies of the CNS in an unusual association: the concomitant presentation of the micropituitarism and cortical dysplasia. To our knowledge, this association is unreported to date. (orig.)

Leukoencephalopathy following CNS prophylaxis therapy in pediatric leukemia : MR imaging findings

International Nuclear Information System (INIS)

Kim, Jong Sub; Lee, Sang Kwon; Kim, Tae Hun; Kim, Yong Joo; Kang, Duck Sik; Kwon, Soon Hak; Lee, Keon Soo

2001-01-01

To evaluate the MR imaging findings and the usefulness of MR imaging in the diagnosis and follow-up leukoencephalopathy following CNS prophylaxis therapy in pediatric leukemia. We retrospectively evaluated the MR imaging findings of eight children with white matter abnormalities on MR out of seventeen acute leukemic patients with various neuropsychiatric symptoms who received intrathecal methotrexate administration, with or without cranial irradiation. In all cases, initial MR was performed within a week of the onset of neuropsychiatric symptoms. Follow-up MR was performed one to sixteen months after initial study, and the MR imaging findings were compared with the initial findings. The initial MR imaging findings were classified into three categories : focal or multifocal white matter abnormalities (3/8), and diffuse white matter abnormalities without enhancement (3/8), and diffuse white matter abnormalities with enhancement (2/8). At follow-up MR, diffuse or focal atrophic changes were noted in all children. White matter abnormalities improved in two out of three patients with focal or multifocal white matter abnormalities. In five with diffuse white matter abnormalities, the extent of these showed no significant change, but contrast enhancement was markedly reduced in two children in whom diffuse white matter abnormalities with enhancement had been demonstrated. In pediatric leukemia, the MR imaging findings of leukoencephalopathy following CNS prophylaxis therapy are variable, but are specific with the clinical history of neuropsychiatric symptoms after intrathecal methotrexate administration, with or without cranial irradiation. The MR imaging is valuable in the diagnosis and follow-up of leukoencephalopathy following CNS prophylaxis therapy in pediatric leukemia

Blood-CNS Barrier Impairment in ALS Patients versus an Animal Model

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Svitlana eGarbuzova-Davis

2014-02-01

Full Text Available Amyotrophic lateral sclerosis (ALS is a severe neurodegenerative disease with a compli-cated and poorly understood pathogenesis. Recently, alterations in the blood-Central Nervous System barrier (B-CNS-B have been recognized as a key factor possibly aggravating motor neuron damage. The majority of findings on ALS microvascular pathology have been deter-mined in mutant SOD1 rodent models, identifying barrier damage during disease develop-ment which might similarly occur in familial ALS patients carrying the SOD1 mutation. However, our knowledge of B-CNS-B competence in sporadic ALS (SALS has been limited. We recently showed structural and functional impairment in postmortem gray and white mat-ter microvessels of medulla and spinal cord tissue from SALS patients, suggesting pervasive barrier damage. Although numerous signs of barrier impairment (endothelial cell degenera-tion, capillary leakage, perivascular edema, downregulation of tight junction proteins, and microhemorrhages are indicated in both mutant SOD1 animal models of ALS and SALS pa-tients, other pathogenic barrier alterations have as yet only been identified in SALS patients. Pericyte degeneration, perivascular collagen IV expansion, and white matter capillary abnor-malities in SALS patients are significant barrier related pathologies yet to be noted in ALS SOD1 animal models. In the current review, these important differences in blood-CNS barrier damage between ALS patients and animal models, which may signify altered barrier transport mechanisms, are discussed. Understanding discrepancies in barrier condition between ALS patients and animal models may be crucial for developing effective therapies.

Cone beam tomography of the heart using single-photon emission-computed tomography

International Nuclear Information System (INIS)

Gullberg, G.T.; Christian, P.E.; Zeng, G.L.; Datz, F.L.; Morgan, H.T.

1991-01-01

The authors evaluated cone beam single-photon emission-computed tomography (SPECT) of the heart. A new cone beam reconstruction algorithm was used to reconstruct data collected from short scan acquisitions (of slightly more than 180 degrees) of a detector anteriorally traversing a noncircular orbit. The less than 360 degrees acquisition was used to minimize the attenuation artifacts that result from reconstructing posterior projections of 201T1 emissions from the heart. The algorithm includes a new method for reconstructing truncated projections of background tissue activity that eliminates reconstruction ring artifacts. Phantom and patient results are presented which compare a high-resolution cone beam collimator (50-cm focal length; 6.0-mm full width at half maximum [FWHM] at 10 cm) to a low-energy general purpose (LEGP) parallel hole collimator (8.2-mm FWHM at 10 cm) which is 1.33 times more sensitive. The cone beam tomographic results are free of reconstruction artifacts and show improved spatial and contrast resolution over that obtained with the LEGP parallel hole collimator. The limited angular sampling restrictions and truncation problems associated with cone beam tomography do not deter from obtaining diagnostic information. However, even though these preliminary results are encouraging, a thorough clinical study is still needed to investigate the specificity and sensitivity of cone beam tomography

Interleukin-6, vascular endothelial growth factor and transforming growth factor beta 1 in canine steroid responsive meningitis-arteritis

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Maiolini Arianna

2013-02-01

Full Text Available Abstract Background Steroid Responsive Meningitis-Arteritis (SRMA is a common cause of inflammation of the canine central nervous system (CNS. To investigate if transforming growth factor beta 1 (TGF-β1, interleukin-6 (IL-6 and vascular endothelial growth factor (VEGF are involved in the production of excessive immunoglobulin A (IgA, the induction of acute phase proteins and in the development of a systemic necrotizing vasculitis, characteristic of SRMA, these three signalling proteins were evaluated. Results Cerebrospinal fluid (CSF and serum samples of dogs during the acute phase of SRMA (SRMA were tested for IL-6, VEGF and TGF- β1. Results were compared to those of dogs affected with SRMA during treatment (SRMA Th and during relapse (SRMA R, to dogs with other meningoencephalomyelitides (ME, with miscellaneous non-inflammatory diseases of the CNS (CNS-Mix, with idiopathic epilepsy (IE, with systemic inflammatory diseases (Syst. Infl. and with healthy dogs (Healthy. Concentrations of IL-6 and VEGF in CSF were significantly elevated in the SRMA group compared to the other disease categories (p 1 were increased in SRMA group, but statistically significant differences were found only in comparison with Healthy and CNS-Mix groups. No differences were detected in the serum concentrations of TGF-β1 between the different groups. In untreated SRMA patients, a positive correlation (rSpear = 0.3549; P = 0.0337 between concentrations of TGF-β1 and IgA concentration was found in CSF, while concentrations of IL-6 and VEGF in CSF positively correlated with the degree of pleocytosis (rSpear = 0.8323; P Spear = 0.5711; P = 0.0166, respectively. Conclusions Our results suggest that these three signalling proteins are biomarkers of disease activity in SRMA. VEGF might play an important role in the development of a systemic arteritis. TGF-β1 is considered to be involved in the excessive IgA production, while IL-6 in the pleocytosis

The imaging appearances of intracranial CNS infections in adult HIV and AIDS patients

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Offiah, C.E. [Department of Neuroradiology, Hope Hospital, Stott Lane, Salford, Manchester (United Kingdom)]. E-mail: chockycj@yahoo.co.uk; Turnbull, I.W. [Department of Neuroradiology, Hope Hospital, Stott Lane, Salford, Manchester (United Kingdom)

2006-05-15

The spectrum of pathology affecting the central nervous system (CNS) in patients suffering from acquired immunodeficiency syndrome (AIDS) is broad and comprises predominantly opportunistic infections and neoplasms. It is estimated that approximately one-third of all patients with AIDS develop neurological complications. The organisms responsible for AIDS are human retroviruses: primarily the human immunodeficiency virus type 1 (HIV). In this review we shall focus on the neurological complications of HIV and AIDS which are applicable to the more frequently occurring intracranial infective organisms. Attention will be paid specifically to those CNS manifestations occurring in the adult HIV and AIDS population as infection in the paediatric HIV and AIDS group, although bearing some similarities, demonstrates some important differences.

The imaging appearances of intracranial CNS infections in adult HIV and AIDS patients

International Nuclear Information System (INIS)

Offiah, C.E.; Turnbull, I.W.

2006-01-01

The spectrum of pathology affecting the central nervous system (CNS) in patients suffering from acquired immunodeficiency syndrome (AIDS) is broad and comprises predominantly opportunistic infections and neoplasms. It is estimated that approximately one-third of all patients with AIDS develop neurological complications. The organisms responsible for AIDS are human retroviruses: primarily the human immunodeficiency virus type 1 (HIV). In this review we shall focus on the neurological complications of HIV and AIDS which are applicable to the more frequently occurring intracranial infective organisms. Attention will be paid specifically to those CNS manifestations occurring in the adult HIV and AIDS population as infection in the paediatric HIV and AIDS group, although bearing some similarities, demonstrates some important differences

Dosimetric Comparison and Potential for Improved Clinical Outcomes of Paediatric CNS Patients Treated with Protons or IMRT

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Armoogum, Kris S., E-mail: kris.armoogum@nhs.net [Department of Radiotherapy Physics, Royal Derby Hospital, Derby Hospitals NHS Foundation Trust, Uttoxeter Road, Derby DE22 3NE (United Kingdom); Thorp, Nicola [The Clatterbridge Cancer Centre NHS Foundation Trust, Clatterbridge Road, Bebington, Wirral CH63 4JY (United Kingdom)

2015-04-28

Background: We compare clinical outcomes of paediatric patients with CNS tumours treated with protons or IMRT. CNS tumours form the second most common group of cancers in children. Radiotherapy plays a major role in the treatment of many of these patients but also contributes to late side effects in long term survivors. Radiation dose inevitably deposited in healthy tissues outside the clinical target has been linked to detrimental late effects such as neurocognitive, behavioural and vascular effects in addition to endocrine abnormalities and second tumours. Methods: A literature search was performed using keywords: protons, IMRT, CNS and paediatric. Of 189 papers retrieved, 10 were deemed relevant based on title and abstract screening. All papers directly compared outcomes from protons with photons, five papers included medulloblastoma, four papers each included craniopharyngioma and low grade gliomas and three papers included ependymoma. Results: This review found that while proton beam therapy offered similar clinical target coverage, there was a demonstrable reduction in integral dose to normal structures. Conclusions: This in turn suggests the potential for superior long term outcomes for paediatric patients with CNS tumours both in terms of radiogenic second cancers and out-of-field adverse effects.

Dosimetric Comparison and Potential for Improved Clinical Outcomes of Paediatric CNS Patients Treated with Protons or IMRT

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Kris S. Armoogum

2015-04-01

Full Text Available Background: We compare clinical outcomes of paediatric patients with CNS tumours treated with protons or IMRT. CNS tumours form the second most common group of cancers in children. Radiotherapy plays a major role in the treatment of many of these patients but also contributes to late side effects in long term survivors. Radiation dose inevitably deposited in healthy tissues outside the clinical target has been linked to detrimental late effects such as neurocognitive, behavioural and vascular effects in addition to endocrine abnormalities and second tumours. Methods: A literature search was performed using keywords: protons, IMRT, CNS and paediatric. Of 189 papers retrieved, 10 were deemed relevant based on title and abstract screening. All papers directly compared outcomes from protons with photons, five papers included medulloblastoma, four papers each included craniopharyngioma and low grade gliomas and three papers included ependymoma. Results: This review found that while proton beam therapy offered similar clinical target coverage, there was a demonstrable reduction in integral dose to normal structures. Conclusions: This in turn suggests the potential for superior long term outcomes for paediatric patients with CNS tumours both in terms of radiogenic second cancers and out-of-field adverse effects.

Flavonoids and the CNS

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Anna K. Jäger

2011-02-01

Full Text Available Flavonoids are present in almost all terrestrial plants, where they provide UV-protection and colour. Flavonoids have a fused ring system consisting of an aromatic ring and a benzopyran ring with a phenyl substituent. The flavonoids can be divided into several classes depending on their structure. Flavonoids are present in food and medicinal plants and are thus consumed by humans. They are found in plants as glycosides. Before oral absorption, flavonoids undergo deglycosylation either by lactase phloridzin hydrolase or cytosolic β-glucocidase. The absorbed aglycone is then conjugated by methylation, sulphatation or glucuronidation. Both the aglycones and the conjugates can pass the blood-brain barrier. In the CNS several flavones bind to the benzodiazepine site on the GABAA-receptor resulting in sedation, anxiolytic or anti-convulsive effects. Flavonoids of several classes are inhibitors of monoamine oxidase A or B, thereby working as anti-depressants or to improve the conditions of Parkinson’s patients. Flavanols, flavanones and anthocyanidins have protective effects preventing inflammatory processes leading to nerve injury. Flavonoids seem capable of influencing health and mood.

Thyroid Hormone in the CNS: Contribution of Neuron-Glia Interaction.

Science.gov (United States)

Noda, Mami

2018-01-01

The endocrine system and the central nervous system (CNS) are intimately linked. Among hormones closely related to the nervous system, thyroid hormones (THs) are critical for the regulation of development and differentiation of neurons and neuroglia and hence for development and function of the CNS. T3 (3,3',5-triiodothyronine), an active form of TH, is important not only for neuronal development but also for differentiation of astrocytes and oligodendrocytes, and for microglial development. In adult brain, T3 affects glial morphology with sex- and age-dependent manner and therefore may affect their function, leading to influence on neuron-glia interaction. T3 is an important signaling factor that affects microglial functions such as migration and phagocytosis via complex mechanisms. Therefore, dysfunction of THs may impair glial function as well as neuronal function and thus disturb the brain, which may cause mental disorders. Investigations on molecular and cellular basis of hyperthyroidism and hypothyroidism will help us to understand changes in neuron-glia interaction and therefore consequent psychiatric symptoms. © 2018 Elsevier Inc. All rights reserved.

The Effects of Gx, Gy and Gz Forces on Cone Mesopic Vision

Science.gov (United States)

1983-10-01

of duration less than 1.0 seconds (time frame may vary depending on the source referred to). macular degeneration - Atrophy of the macula of the...rela- 7 tive number of cones itrcreases. In the macula , the visual center of the eye, there is virtually only cones. There are other anatomic...the cones in the center of the macula having a 1:1 synaptic ratio). These features allow small stimuli with minimal separated distances to activate

Neuropsychological screening as a standard of care during discharge from psychiatric hospitalization: the preliminary psychometrics of the CNS Screen.

Science.gov (United States)

Levy, Boaz; Celen-Demirtas, Selda; Surguladze, Tinatin; Eranio, Sara; Ellison, James

2014-03-30

Cost-prohibitive factors currently prevent a warranted integration of neuropsychological screenings into routine psychiatric evaluations, as a standard of care. To overcome this challenge, the current study examined the psychometric properties of a new computerized measure-the CNS Screen. One hundred and twenty six psychiatric inpatients completed the CNS Screen, the Montreal Cognitive Assessment (MoCA), and the Quick Inventory of Depressive Symptomatology-Self Rated (QIDS-SR₁₆) on the day of hospital discharge. Statistical analysis established convergent validity with a moderate correlation between the self-administered CNS Screen and the clinician-administered MoCA (r=0.64). Discriminant validity was implicated by a non-significant correlation with the QIDS-SR₁₆. Concurrent validity was supported by a moderate, negative correlation with patients' age (r=-0.62). In addition, consistent with previous findings, patients with psychotic disorders exhibited significantly poorer performance on the CNS Screen than patients with a mood disorder. Similarly, patients with a formal disability status scored significantly lower than other patients. The CNS Screen was well tolerated by all patients. With further development, this type of measure may provide a cost-effective approach to expanding neuropsychological screenings on inpatient psychiatric units. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Enhancing Psychosocial Outcomes for Young Adult Childhood CNS Cancer Survivors: Importance of Addressing Vocational Identity and Community Integration

Science.gov (United States)

Strauser, David R.; Wagner, Stacia; Wong, Alex W. K.

2012-01-01

The purpose of this study was to examine the relationship between vocational identity, community integration, positive and negative affect, and satisfaction with life in a group of young adult central nervous system (CNS) cancer survivors. Participants in this study included 45 young adult CNS cancer survivors who ranged in age from 18 to 30 years…

Edifice growth, deformation and rift zone development in basaltic setting: Insights from Piton de la Fournaise shield volcano (Réunion Island)

Science.gov (United States)

Michon, Laurent; Cayol, Valérie; Letourneur, Ludovic; Peltier, Aline; Villeneuve, Nicolas; Staudacher, Thomas

2009-07-01

The overall morphology of basaltic volcanoes mainly depends on their eruptive activity (effusive vs. explosive), the geometry of the rift zones and the characteristics of both endogenous and exogenous growth processes. The origin of the steep geometry of the central cone of Piton de la Fournaise volcano, which is unusual for a basaltic effusive volcano, and its deformation are examined with a combination of a detailed morphological analysis, field observations, GPS data from the Piton de la Fournaise Volcano Observatory and numerical models. The new caldera walls formed during the April 2007 summit collapse reveal that the steep cone is composed of a pyroclastic core, inherited from an earlier explosive phase, overlapped by a pile of thin lava flows. This suggests that exogenous processes played a major role in the building of the steep central cone. Magma injections into the cone, which mainly occur along the N25-30 and N120 rift zones, lead to an asymmetric outward inflation concentrated in the cone's eastern half. This endogenous growth progressively tilts the southeast and east flanks of the cone, and induces the development of a dense network of flank fractures. Finally, it is proposed that intrusions along the N120 rift zone are encouraged by stresses induced by magma injections along the N25-30 rift zone.

Evaluation of mechanical and thermal properties of Pine cone fibers reinforced compatibilized polypropylene

International Nuclear Information System (INIS)

Arrakhiz, F.Z.; El Achaby, M.; Benmoussa, K.; Bouhfid, R.; Essassi, E.M.; Qaiss, A.

2012-01-01

Highlights: ► Pine cone fibers are used as reinforcement in thermoplastic matrix. ► Pine cone fiber was alkali treated to remove waxes and non cellulosic component. ► Fiber–matrix adhesion was assured by the use of a SEBS-g-MA as a compatibilizer. -- Abstract: Pine cone fibers are a cellulosic material readily available and can be used as reinforcement in a thermoplastic-based composite. A solid knowledge of their fibrillar morphology and structure is required to evaluate their usefulness as a substitute to other abundant natural fibers. Pine cone fibers were alkali treated prior usage to remove waxes and non cellulosic surface component. Fiber–matrix adhesion was assured by both a styrene–(ethylene–butene)–styrene triblock copolymer grafted with maleic anhydride (SEBS-g-MA) and a linear block copolymer based on styrene and butadiene compatibilizer. Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction, Thermogravimetric analysis (TGA), tensile and torsional tests were employed for Pine cone polypropylene composite and compatibilized composite at different fiber content. Results show a clear improvement in mechanical properties from the use of both alkali treated Pine cone and Pine cone compatibilized with maleic anhydride, a gain of 43% and 49% respectively in the Young’s modulus, as a results of improved adhesion between fibers and matrix at the interface.

℮-conome: an automated tissue counting platform of cone photoreceptors for rodent models of retinitis pigmentosa

Directory of Open Access Journals (Sweden)

Clérin Emmanuelle

2011-12-01

Full Text Available Abstract Background Retinitis pigmentosa is characterized by the sequential loss of rod and cone photoreceptors. The preservation of cones would prevent blindness due to their essential role in human vision. Rod-derived Cone Viability Factor is a thioredoxin-like protein that is secreted by rods and is involved in cone survival. To validate the activity of Rod-derived Cone Viability Factors (RdCVFs as therapeutic agents for treating retinitis Pigmentosa, we have developed e-conome, an automated cell counting platform for retinal flat mounts of rodent models of cone degeneration. This automated quantification method allows for faster data analysis thereby accelerating translational research. Methods An inverted fluorescent microscope, motorized and coupled to a CCD camera records images of cones labeled with fluorescent peanut agglutinin lectin on flat-mounted retinas. In an average of 300 fields per retina, nine Z-planes at magnification X40 are acquired after two-stage autofocus individually for each field. The projection of the stack of 9 images is subject to a threshold, filtered to exclude aberrant images based on preset variables. The cones are identified by treating the resulting image using 13 variables empirically determined. The cone density is calculated over the 300 fields. Results The method was validated by comparison to the conventional stereological counting. The decrease in cone density in rd1 mouse was found to be equivalent to the decrease determined by stereological counting. We also studied the spatiotemporal pattern of the degeneration of cones in the rd1 mouse and show that while the reduction in cone density starts in the central part of the retina, cone degeneration progresses at the same speed over the whole retinal surface. We finally show that for mice with an inactivation of the Nucleoredoxin-like genes Nxnl1 or Nxnl2 encoding RdCVFs, the loss of cones is more pronounced in the ventral retina. Conclusion The automated

℮-conome: an automated tissue counting platform of cone photoreceptors for rodent models of retinitis pigmentosa.

Science.gov (United States)

Clérin, Emmanuelle; Wicker, Nicolas; Mohand-Saïd, Saddek; Poch, Olivier; Sahel, José-Alain; Léveillard, Thierry

2011-12-20

Retinitis pigmentosa is characterized by the sequential loss of rod and cone photoreceptors. The preservation of cones would prevent blindness due to their essential role in human vision. Rod-derived Cone Viability Factor is a thioredoxin-like protein that is secreted by rods and is involved in cone survival. To validate the activity of Rod-derived Cone Viability Factors (RdCVFs) as therapeutic agents for treating retinitis Pigmentosa, we have developed e-conome, an automated cell counting platform for retinal flat mounts of rodent models of cone degeneration. This automated quantification method allows for faster data analysis thereby accelerating translational research. An inverted fluorescent microscope, motorized and coupled to a CCD camera records images of cones labeled with fluorescent peanut agglutinin lectin on flat-mounted retinas. In an average of 300 fields per retina, nine Z-planes at magnification X40 are acquired after two-stage autofocus individually for each field. The projection of the stack of 9 images is subject to a threshold, filtered to exclude aberrant images based on preset variables. The cones are identified by treating the resulting image using 13 variables empirically determined. The cone density is calculated over the 300 fields. The method was validated by comparison to the conventional stereological counting. The decrease in cone density in rd1 mouse was found to be equivalent to the decrease determined by stereological counting. We also studied the spatiotemporal pattern of the degeneration of cones in the rd1 mouse and show that while the reduction in cone density starts in the central part of the retina, cone degeneration progresses at the same speed over the whole retinal surface. We finally show that for mice with an inactivation of the Nucleoredoxin-like genes Nxnl1 or Nxnl2 encoding RdCVFs, the loss of cones is more pronounced in the ventral retina. The automated platform ℮-conome used here for retinal disease is a tool that

Cone-beam CT in paediatric dentistry. DIMITRA project position statement

International Nuclear Information System (INIS)

Oenning, Anne Caroline; Jacobs, Reinhilde; Pauwels, Ruben; Stratis, Andreas; Hedesiu, Mihaela; Salmon, Benjamin

2018-01-01

DIMITRA (dentomaxillofacial paediatric imaging: an investigation towards low-dose radiation induced risks) is a European multicenter and multidisciplinary project focused on optimizing cone-beam CT exposures for children and adolescents. With increasing use of cone-beam CT for dentomaxillofacial diagnostics, concern arises regarding radiation risks associated with this imaging modality, especially for children. Research evidence concerning cone-beam CT indications in children remains limited, while reports mention inconsistent recommendations for dose reduction. Furthermore, there is no paper using the combined and integrated information on the required indication-oriented image quality and the related patient dose levels. In this paper, therefore, the authors initiate an integrated approach based on current evidence regarding image quality and dose, together with the expertise of DIMITRA's members searching for a state of the art. The aim of this DIMITRA position statement is to provide indication-oriented and patient-specific recommendations regarding the main cone-beam CT applications in the pediatric field. The authors will review this position statement document when results regarding multidisciplinary approaches evolve, in a period of 5 years or earlier. (orig.)

Melanocortin signaling in the CNS directly regulates circulating cholesterol

OpenAIRE

Perez-Tilve, Diego; Hofmann, Susanna M; Basford, Joshua; Nogueiras, Ruben; Pfluger, Paul T; Patterson, James T; Grant, Erin; Wilson-Perez, Hilary E; Granholm, Norman A; Arnold, Myrtha; Trevaskis, James L; Butler, Andrew A; Davidson, William S; Woods, Stephen C; Benoit, Stephen C

2010-01-01

Cholesterol circulates in the blood in association with triglycerides and other lipids, and elevated blood low-density lipoprotein cholesterol carries a risk for metabolic and cardiovascular disorders, whereas high-density lipoprotein (HDL) cholesterol in the blood is thought to be beneficial. Circulating cholesterol is the balance among dietary cholesterol absorption, hepatic synthesis and secretion, and the metabolism of lipoproteins by various tissues. We found that the CNS is also an impo...

Characteristics of cones and seeds of Pinus sibirica Du Tour at tree line in the Central Altai

Directory of Open Access Journals (Sweden)

E. O. Filimonova

2016-02-01

Full Text Available We studied the cones of Siberian stone pine (Pinus sibirica Du Tour at its treeline in the forest tundra ecotone in the Severo-Chuisky Range, the Altai Mountains, Russia. We have registered length, diameter and form of apophysis, the number of sterile and fertile scales in the cones, the number of ovules and the number of seeds, including developed and underdeveloped seeds, and the developed seeds/ovules ratio. The cones and seeds are produced below 2350 m a. s. l under arid conditions (east-south-eastern slope and below 2390 m a. s. l. under more humid conditions (west-north-western slope. These altitudes are reproductive line of Siberian stone pine. The predominant forms of the cones near this line are cone-like, spherical and cylindrical. Apophyses are mostly tuberous, hook-like and flat. The most (50% of the sampled cones have the cylindrical form. The number of ovules varied from 84.6 to 102.4 per cone, the number of seeds were from 76.7 to 98.9 per cone, and the developed seeds were 74.5 to 95.7 per cone. The lowest proportion of developed seeds was registered for cones sampled on arid east-south-eastern slope in 2011. The cones with tuberous apophysis have the highest number of seeds (up to 103.6–110 per cone under more humid and 87.3–104.4 per cone under more arid conditions. Cones gathered at 2235–2390 m a. s. l. have low presence of underdeveloped seeds (1.0 to 3.2 % and high developed seeds/ovules ratio (87.2 to 93.7 %.

Correlated cone noise decreases rod signal contributions to the post-receptoral pathways.

Science.gov (United States)

Hathibelagal, Amithavikram R; Feigl, Beatrix; Zele, Andrew J

2018-04-01

This study investigated how invisible extrinsic temporal white noise that correlates with the activity of one of the three [magnocellular (MC), parvocellular (PC), or koniocellular (KC)] post-receptoral pathways alters mesopic rod signaling. A four-primary photostimulator provided independent control of the rod and three cone photoreceptor excitations. The rod contributions to the three post-receptoral pathways were estimated by perceptually matching a 20% contrast rod pulse by independently varying the LMS (MC pathway), +L-M (PC pathway), and S-cone (KC pathway) excitations. We show that extrinsic cone noise caused a predominant decrease in the overall magnitude and ratio of the rod contributions to each pathway. Thus, the relative cone activity in the post-receptoral pathways determines the relative mesopic rod inputs to each pathway.

Polymorphic New World monkeys with more than three M/L cone types

Science.gov (United States)

Jacobs, Gerald H.; Deegan, Jess F.

2005-10-01

Most New World (platyrrhine) monkeys have M/L cone photopigment polymorphisms that map directly into individual variations in visual sensitivity and color vision. We used electroretinogram flicker photometry to examine M/L cone photopigments in the New World monkey Callicebus moloch (the dusky Titi). Like other New World monkeys, this species has an M/L cone photopigment polymorphism that reflects the presence of X-chromosome opsin gene alleles. However, unlike other platyrrhines in which three M/L photopigments are typical, Callicebus has a total of five M/L cone photopigments. The peak sensitivity values for these pigments extend across the range from 530 to 562 nm. The result is an enhanced array of potential color vision phenotypes in this species.

On the zero mode problem of the light-cone quantization

International Nuclear Information System (INIS)

Huang, Suzhou; Lin, Wei

1993-01-01

The light-cone quantization for theories involving arbitrarily interacting scalars is studied systematically. The zero mode, which plays a special role in the light-cone quantization, is treated explicitly. The arguments utilize a lattice regularization and the constrained path-integral method. It is shown, to all orders in coupling constants or the loop expansion, that the ghost fields, introduced to enforce the constraints, decouple from all the virtual processes in the infinite-volume limit. The only possibility for the light-cone quantization to deviate from the equal-time quantization is when the interaction is such that the bosonic ghost fields develop expectation values and consequently alter the location of the minimum point of the effective potential. 24 refs

Kornwell-Norton moments and electromagnetic current commutator expansion on light cone

International Nuclear Information System (INIS)

Vitsorek, Eh.; Motts, G.

1975-01-01

Relations have been obtained between the asymptotic behaviour of moments and the commutator of electromagnetic currents on the light cone. The existence of the operator decomposition on the light cone and the applicability of Fourier transformation to it has not been assumed

Genetics Home Reference: cone-rod dystrophy

Science.gov (United States)

... common cause of autosomal recessive cone-rod dystrophy , accounting for 30 to 60 percent of cases. At ... dystrophy play essential roles in the structure and function of specialized light receptor cells (photoreceptors) in the ...

Spectral sensitivity of the feedback signal from horizontal cells to cones in goldfish retina

NARCIS (Netherlands)

Kraaij, D. A.; Kamermans, M.; Spekreijse, H.

1998-01-01

The spectral sensitivity of cones in isolated goldfish retina was determined with whole-cell recording techniques. Three spectral classes of cones were found with maximal sensitivities around 620 nm, 540 nm, and 460 nm. UV-cones were not found because our stimulator did not allow effective

Inflammatory cytokines in the brain: does the CNS shape immune responses?

DEFF Research Database (Denmark)

Owens, T; Renno, T; Taupin, V

1994-01-01

Immune responses in the central nervous system (CNS) have traditionally been regarded as representing the intrusion of an unruly, ill-behaved mob of leukocytes into the well-ordered and organized domain of thought and reason. However, results accumulated over the past few years suggest that, far ...

The sine-Gordon model and the small κ+ region of light- cone perturbation theory

International Nuclear Information System (INIS)

Griffin, P.A.

1992-01-01

The non-perturbative ultraviolet divergence of the sine-Gordon model is used to study the k + = 0 region of light-cone perturbation theory. The light-cone vacuum is shown to be unstable at the non- perturbative β 2 = 8π critical point by a light-cone version of Coleman's variational method. Vacuum bubbles, which are k + = 0 diagram in light-cone field theory and are individually finite and non-vanishing for all β, conspire to generate ultraviolet divergences of the light-cone energy density. The k + = 0 region of momentum also contributed to connected Green's functions: the connected two point function will not diverge, as it should, at the critical point unless diagrams which contribute only at k + = 0 are properly included. This analysis shows in a simple way how the k + = 0 region cannot be ignored even for connected diagrams. This phenomenon is expected to occur in higher dimensional gauge theories starting at two loop order in light-cone perturbation theory

Non-dissipative electromagnetic media with two Lorentz null cones

International Nuclear Information System (INIS)

Dahl, Matias F.

2013-01-01

We study Maxwell’s equations on a 4-manifold where the electromagnetic medium is modeled by an antisymmetric (2/2 )-tensor with 21 real coefficients. In this setting the Fresnel surface is a fourth-order polynomial surface that describes the dynamical response of the medium in the geometric optics limit. For example, in an isotropic medium the Fresnel surface is a Lorentz null cone. The contribution of this paper is the pointwise description of all electromagnetic medium tensors κ with real coefficients that satisfy the following three conditions: (i)medium κ is invertible, (ii)medium κ is skewon-free, or non-dissipative, (iii)the Fresnel surface of κ is the union of two distinct Lorentz null cones. We show that there are only three classes of media with these properties and give explicit expressions in local coordinates for each class. - Highlights: ► We find two new electromagnetic media classes for which the Fresnel surface decomposes into two light cones. ► In a suitable setting we classify all electromagnetic media where this is the case. ► We find an electromagnetic medium tensor with three different signal speeds in one direction. ► The work is related to [5], which classifies all media with one light cone (in a suitable setting).

Use of magnetic resonance imaging in short stature: data from National Cooperative Growth Study (NCGS) Substudy 8.

Science.gov (United States)

Kemp, Stephen F; Alter, Craig A; Dana, Ken; Baptista, Joyce; Blethen, Sandra L

2002-05-01

The primary use of magnetic resonance imaging (MRI) in the evaluation of children with short stature (SS) is to discover lesions in the central nervous system (CNS), particularly tumors that may require intervention. MRI has a secondary role in identifying structural abnormalities responsible for growth hormone deficiency (GHD). We examined data from the National Cooperative Growth Study (NCGS) Substudy 8 to determine how American physicians are using MRI in evaluating children with SS. Of the 21,738 short children enrolled in NCGS, 5% underwent MRI during their follow-up. Children who had GH stimulation testing were more likely to have had an MRI than those in whom no GH stimulation test was performed (19% vs 2%, p 10 ng/ml), respectively. Abnormalities unrelated to the hypothalamus or pituitary represented 30% of these findings, while disorders in pituitary anatomy, including pituitary hypoplasia, pituitary stalk interruption, and ectopic posterior pituitary, represented an additional 30% of abnormal MRI examinations. CNS tumors comprised 23% of abnormal findings in these patients. We conclude that MRI provides significant value in the evaluation of children with SS, by identifying CNS tumors associated with growth failure as well as anatomical abnormalities of the pituitary. These findings are useful in confirming the diagnosis of GHD in children and identifying potential candidates for continued GH replacement in adulthood.

Determination of the Resistance of Cone-Shaped Solid Electrodes

DEFF Research Database (Denmark)

Frandsen, Henrik Lund; Hendriksen, Peter Vang; Koch, Søren

2017-01-01

during processing can be avoided. Newman's formula for current constriction in the electrolyte is then used to deduce the active contact area based on the ohmic resistance of the cell, and from this the surface specific electro-catalytic activity. However, for electrode materials with low electrical......A cone-shaped electrode pressed into an electrolyte can with advantage be utilized to characterize the electro-catalytic properties of the electrode, because it is less dependent on the electrode microstructure than e.g. thin porous composite electrodes, and reactions with the electrolyte occurring...... conductivity (like Ce1-xPrxO2-δ), the resistance of the cell is significantly influenced by the ohmic resistance of the cone electrode, wherefore it must be included. In this work the ohmic resistance of a cone is modelled analytically based on simplified geometries. The two analytical models only differ...

Effect of inlet cone pipe angle in catalytic converter

Science.gov (United States)

Amira Zainal, Nurul; Farhain Azmi, Ezzatul; Arifin Samad, Mohd

2018-03-01

The catalytic converter shows significant consequence to improve the performance of the vehicle start from it launched into production. Nowadays, the geometric design of the catalytic converter has become critical to avoid the behavior of backpressure in the exhaust system. The backpressure essentially reduced the performance of vehicles and increased the fuel consumption gradually. Consequently, this study aims to design various models of catalytic converter and optimize the volume of fluid flow inside the catalytic converter by changing the inlet cone pipe angles. Three different geometry angles of the inlet cone pipe of the catalytic converter were assessed. The model is simulated in Solidworks software to determine the optimum geometric design of the catalytic converter. The result showed that by decreasing the divergence angle of inlet cone pipe will upsurge the performance of the catalytic converter.

Light-cone quantized QCD and novel hadron phenomenology

International Nuclear Information System (INIS)

Brodsky, S.J.

1997-09-01

The authors reviews progress made in solving gauge theories such as collinear quantum chromodynamics using light-cone Hamiltonian methods. He also shows how the light-cone Fock expansion for hadron wavefunctions can be used to compute operator matrix elements such as decay amplitudes, form factors, distribution amplitudes, and structure functions, and how it provides a tool for exploring novel features of QCD. The author also reviews commensurate scale relations, leading-twist identities which relate physical observables to each other, thus eliminating renormalization scale and scheme ambiguities in perturbative QCD predictions

Design and development of new collimator cones for fractionated stereotactic radiation therapy in Samsung Medical Center.

Science.gov (United States)

Ahn, Y C; Ju, S G; Kim, D Y; Choi, D R; Huh, S J; Park, Y H; Lim, D H; Kim, M K

1999-05-01

In stereotactic radiotherapy using X-Knife system, the commercially supplied collimator cone system had a few mechanical limitations. The authors have developed new collimator cones to overcome these limitations and named them "SMC type" collimator cones. We made use of cadmium-free cerrobend alloy within the stainless steel cylinder housing. We made nine cones of relatively larger sizes (3.0 cm to 7.0 cm in diameter) and of shorter length with bigger clearance from the isocenter than the commercial cones. The cone housing and the collimator cones were designed to insert into the wedge mount of the gantry head to enable double-exposure linac-gram taking. The mechanical accuracy of pointing to the isocenter was tested by ball test and cone rotation test, and the dosimetric measurements were performed, all of which were with satisfactory results. A new innovative quality assurance procedure using linac-grams on the patients at the actual treatment setup was attempted after taking 10 sets of AP and lateral linac-grams and the overall mechanical isocenter accuracy was excellent (average error = 0.4 +/- 0.2 mm). We have developed the SMC type collimator cone system mainly for fractionated stereotactic radiation therapy use with our innovative ideas. The new cones' mechanical accuracy and physical properties were satisfactory for clinical use, and the verification of the isocenter accuracy on the actual treatment setup has become possible.

Chapter 51: How to Build a Simple Cone Search Service Using a Local Database

Science.gov (United States)

Kent, B. R.; Greene, G. R.

The cone search service protocol will be examined from the server side in this chapter. A simple cone search service will be setup and configured locally using MySQL. Data will be read into a table, and the Java JDBC will be used to connect to the database. Readers will understand the VO cone search specification and how to use it to query a database on their local systems and return an XML/VOTable file based on an input of RA/DEC coordinates and a search radius. The cone search in this example will be deployed as a Java servlet. The resulting cone search can be tested with a verification service. This basic setup can be used with other languages and relational databases.

Internal Reflection Sensor for the Cone Penetrometer. Innovative Technology Summary Report

International Nuclear Information System (INIS)

None

2001-01-01

The Internal Reflection Sensor, developed by EIC Laboratories, Inc. as a cone penetrometer based technology, provides real-time detection of subsurface non-aqueous phase liquids (NAPLs). The internal reflection element is positioned against the wall of the cone penetrometer probe such that its sensing face is in contact with the soil or groundwater as the cone is pushed into the subsurface. When NAPL is present and in contact with the sensing face, the internally reflected light is diminished. This results in a decrease in the signal output by the detector - a positive indicator of NAPL presence

Comparative antibiogram of coagulase-negative Staphylococci (CNS associated with subclinical and clinical mastitis in dairy cows

Directory of Open Access Journals (Sweden)

B. K. Bansal

2015-03-01

Full Text Available Aim: The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. Materials and Methods: The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17. Results: Isolates were highly susceptible to chloramphenicol (98.3%, gentamicin (93.1%, streptomycin (91.4%, linezolid (91.4%, ceftixozime (87.9%, cloxacillin (86.2%, clotrimazole (86.2%, bacitracin (86.2%, enrofloxacin (84.5% and ceftrioxone + tazobactum (70.7%, while resistance was observed against amoxicillin (77.6%, penicillin (75.9%, ampicillin (74.1% and cefoperazone (51.7%. Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. Conclusion: CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.