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Sample records for density deficit ca

  1. Sleep deprivation causes memory deficits by negatively impacting neuronal connectivity in hippocampal area CA1

    Science.gov (United States)

    Havekes, Robbert; Park, Alan J; Tudor, Jennifer C; Luczak, Vincent G; Hansen, Rolf T; Ferri, Sarah L; Bruinenberg, Vibeke M; Poplawski, Shane G; Day, Jonathan P; Aton, Sara J; Radwańska, Kasia; Meerlo, Peter; Houslay, Miles D; Baillie, George S; Abel, Ted

    2016-01-01

    Brief periods of sleep loss have long-lasting consequences such as impaired memory consolidation. Structural changes in synaptic connectivity have been proposed as a substrate of memory storage. Here, we examine the impact of brief periods of sleep deprivation on dendritic structure. In mice, we find that five hours of sleep deprivation decreases dendritic spine numbers selectively in hippocampal area CA1 and increased activity of the filamentous actin severing protein cofilin. Recovery sleep normalizes these structural alterations. Suppression of cofilin function prevents spine loss, deficits in hippocampal synaptic plasticity, and impairments in long-term memory caused by sleep deprivation. The elevated cofilin activity is caused by cAMP-degrading phosphodiesterase-4A5 (PDE4A5), which hampers cAMP-PKA-LIMK signaling. Attenuating PDE4A5 function prevents changes in cAMP-PKA-LIMK-cofilin signaling and cognitive deficits associated with sleep deprivation. Our work demonstrates the necessity of an intact cAMP-PDE4-PKA-LIMK-cofilin activation-signaling pathway for sleep deprivation-induced memory disruption and reduction in hippocampal spine density. DOI: http://dx.doi.org/10.7554/eLife.13424.001 PMID:27549340

  2. Transient increase in Zn2+ in hippocampal CA1 pyramidal neurons causes reversible memory deficit.

    Directory of Open Access Journals (Sweden)

    Atsushi Takeda

    Full Text Available The translocation of synaptic Zn(2+ to the cytosolic compartment has been studied to understand Zn(2+ neurotoxicity in neurological diseases. However, it is unknown whether the moderate increase in Zn(2+ in the cytosolic compartment affects memory processing in the hippocampus. In the present study, the moderate increase in cytosolic Zn(2+ in the hippocampus was induced with clioquinol (CQ, a zinc ionophore. Zn(2+ delivery by Zn-CQ transiently attenuated CA1 long-term potentiation (LTP in hippocampal slices prepared 2 h after i.p. injection of Zn-CQ into rats, when intracellular Zn(2+ levels was transiently increased in the CA1 pyramidal cell layer, followed by object recognition memory deficit. Object recognition memory was transiently impaired 30 min after injection of ZnCl(2 into the CA1, but not after injection into the dentate gyrus that did not significantly increase intracellular Zn(2+ in the granule cell layer of the dentate gyrus. Object recognition memory deficit may be linked to the preferential increase in Zn(2+ and/or the preferential vulnerability to Zn(2+ in CA1 pyramidal neurons. In the case of the cytosolic increase in endogenous Zn(2+ in the CA1 induced by 100 mM KCl, furthermore, object recognition memory was also transiently impaired, while ameliorated by co-injection of CaEDTA to block the increase in cytosolic Zn(2+. The present study indicates that the transient increase in cytosolic Zn(2+ in CA1 pyramidal neurons reversibly impairs object recognition memory.

  3. Transient increase in Zn2+ in hippocampal CA1 pyramidal neurons causes reversible memory deficit.

    Science.gov (United States)

    Takeda, Atsushi; Takada, Shunsuke; Nakamura, Masatoshi; Suzuki, Miki; Tamano, Haruna; Ando, Masaki; Oku, Naoto

    2011-01-01

    The translocation of synaptic Zn(2+) to the cytosolic compartment has been studied to understand Zn(2+) neurotoxicity in neurological diseases. However, it is unknown whether the moderate increase in Zn(2+) in the cytosolic compartment affects memory processing in the hippocampus. In the present study, the moderate increase in cytosolic Zn(2+) in the hippocampus was induced with clioquinol (CQ), a zinc ionophore. Zn(2+) delivery by Zn-CQ transiently attenuated CA1 long-term potentiation (LTP) in hippocampal slices prepared 2 h after i.p. injection of Zn-CQ into rats, when intracellular Zn(2+) levels was transiently increased in the CA1 pyramidal cell layer, followed by object recognition memory deficit. Object recognition memory was transiently impaired 30 min after injection of ZnCl(2) into the CA1, but not after injection into the dentate gyrus that did not significantly increase intracellular Zn(2+) in the granule cell layer of the dentate gyrus. Object recognition memory deficit may be linked to the preferential increase in Zn(2+) and/or the preferential vulnerability to Zn(2+) in CA1 pyramidal neurons. In the case of the cytosolic increase in endogenous Zn(2+) in the CA1 induced by 100 mM KCl, furthermore, object recognition memory was also transiently impaired, while ameliorated by co-injection of CaEDTA to block the increase in cytosolic Zn(2+). The present study indicates that the transient increase in cytosolic Zn(2+) in CA1 pyramidal neurons reversibly impairs object recognition memory.

  4. Neural activity changes underlying the working memory deficit in alpha-CaMKII heterozygous knockout mice

    Directory of Open Access Journals (Sweden)

    Naoki Matsuo

    2009-09-01

    Full Text Available The alpha-isoform of calcium/calmodulin-dependent protein kinase II (α-CaMKII is expressed abundantly in the forebrain and is considered to have an essential role in synaptic plasticity and cognitive function. Previously, we reported that mice heterozygous for a null mutation of α-CaMKII (α-CaMKII+/- have profoundly dysregulated behaviors including a severe working memory deficit, which is an endophenotype of schizophrenia and other psychiatric disorders. In addition, we found that almost all the neurons in the dentate gyrus (DG of the mutant mice failed to mature at molecular, morphological and electrophysiological levels. In the present study, to identify the brain substrates of the working memory deficit in the mutant mice, we examined the expression of the immediate early genes (IEGs, c-Fos and Arc, in the brain after a working memory version of the eight-arm radial maze test. c-Fos expression was abolished almost completely in the DG and was reduced significantly in neurons in the CA1 and CA3 areas of the hippocampus, central amygdala, and medial prefrontal cortex (mPFC. However, c-Fos expression was intact in the entorhinal and visual cortices. Immunohistochemical studies using arc promoter driven dVenus transgenic mice demonstrated that arc gene activation after the working memory task occurred in mature, but not immature neurons in the DG of wild-type mice. These results suggest crucial insights for the neural circuits underlying spatial mnemonic processing during a working memory task and suggest the involvement of α-CaMKII in the proper maturation and integration of DG neurons into these circuits.

  5. Glucose administration attenuates spatial memory deficits induced by chronic low-power-density microwave exposure.

    Science.gov (United States)

    Lu, Yonghui; Xu, Shangcheng; He, Mindi; Chen, Chunhai; Zhang, Lei; Liu, Chuan; Chu, Fang; Yu, Zhengping; Zhou, Zhou; Zhong, Min

    2012-07-16

    Extensive evidence indicates that glucose administration attenuates memory deficits in rodents and humans, and cognitive impairment has been associated with reduced glucose metabolism and uptake in certain brain regions including the hippocampus. In the present study, we investigated whether glucose treatment attenuated memory deficits caused by chronic low-power-density microwave (MW) exposure, and the effect of MW exposure on hippocampal glucose uptake. We exposed Wistar rats to 2.45 GHz pulsed MW irradiation at a power density of 1 mW/cm(2) for 3 h/day, for up to 30 days. MW exposure induced spatial learning and memory impairments in rats. Hippocampal glucose uptake was also reduced by MW exposure in the absence or presence of insulin, but the levels of blood glucose and insulin were not affected. However, these spatial memory deficits were reversed by systemic glucose treatment. Our results indicate that glucose administration attenuates the spatial memory deficits induced by chronic low-power-density MW exposure, and reduced hippocampal glucose uptake may be associated with cognitive impairment caused by MW exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Development of Low Density CaMg-A1-Based Bulk Metallic Glasses (Preprint)

    National Research Council Canada - National Science Library

    Senkov, O. N; Scott, J. M; Miracle, D. B

    2006-01-01

    Low density Ca-Mg-Al-based bulk metallic glasses containing additionally Cu and Zn, were produced by a copper mold casting method as wedge-shaped samples with thicknesses varying from 0.5 mm to 10 rom...

  7. Visual sensory processing deficits in patients with bipolar disorder revealed through high-density electrical mapping.

    LENUS (Irish Health Repository)

    Yeap, Sherlyn

    2009-11-01

    BACKGROUND: Etiological commonalities are apparent between bipolar disorder and schizophrenia. For example, it is becoming clear that both populations show similar electrophysiological deficits in the auditory domain. Recent studies have also shown robust visual sensory processing deficits in patients with schizophrenia using the event-related potential technique, but this has not been formally tested in those with bipolar disorder. Our goal here was to assess whether early visual sensory processing in patients with bipolar disorder, as indexed by decreased amplitude of the P1 component of the visual evoked potential (VEP), would show a similar deficit to that seen in those with schizophrenia. Since the P1 deficit has already been established as an endophenotype in schizophrenia, a finding of commonality between disorders would raise the possibility that it represents a measure of common genetic liability. METHODS: We visually presented isolated-check stimuli to euthymic patients with a diagnosis of bipolar disorder and age-matched healthy controls within a simple go\\/no-go task and recorded VEPs using high-density (72-channel) electroencephalography. RESULTS: The P1 VEP amplitude was substantially reduced in patients with bipolar disorder, with an effect size of f = 0.56 (large according to Cohen\\'s criteria). LIMITATIONS: Our sample size was relatively small and as such, did not allow for an examination of potential relations between the physiologic measures and clinical measures. CONCLUSION: This reduction in P1 amplitude among patients with bipolar disorder represents a dysfunction in early visual processing that is highly similar to that found repeatedly in patients with schizophrenia and their healthy first-degree relatives. Since the P1 deficit has been related to susceptibility genes for schizophrenia, our results raise the possibility that the deficit may in fact be more broadly related to the development of psychosis and that it merits further

  8. Size and receptor density of glutamatergic synapses: a viewpoint from left-right asymmetry of CA3-CA1 connections

    Directory of Open Access Journals (Sweden)

    Yoshiaki Shinohara

    2009-07-01

    Full Text Available Synaptic plasticity is considered to be the main mechanism for learning and memory. Excitatory synapses in the cerebral cortex and hippocampus undergo plastic changes during development and in response to electric stimulation. It is widely accepted that this process is mediated by insertion and elimination of various glutamate receptors. In a series of recent investigations on left-right asymmetry of hippocampal CA3-CA1 synapses, glutamate receptor subunits have been found to have distinctive expression patterns that depend on the postsynaptic density (PSD area. Particularly notable are the GluR1 AMPA receptor subunit and NR2B NMDA receptor subunit, where receptor density has either a supra-linear (GluR1 AMPA or inverse (NR2B NMDAR relationship to the PSD area. We review current understanding of structural and physiological synaptic plasticity and propose a scheme to classify receptor subtypes by their expression pattern with respect to PSD area.

  9. Density functional study of CaN mono and bilayer on Cu(001)

    International Nuclear Information System (INIS)

    Zahedifar, Maedeh; Hashemifar, S. Javad; Akbarzadeh, Hadi

    2014-01-01

    Density functional - pseudopotential calculations are performed to provide first-principles insights into magnetic behaviour of bulk CaN and CaN monolayers on Cu(001) in the rock-salt (RS) and zinc-blende (ZB) structures. Our results indicate that both RS- and ZB-CaN exhibit half-metallic ferromagnetism originated from the incomplete 2p shell of the nitrogen ion. In contrast to the bulk CaN, the CaN monolayers on Cu(001) generally favor ZB structure. We argue that the more stable ZB-CaN thin films on Cu(001) are nonmagnetic, because of strong Cu-N bonding at the interface, while the less stable Ca terminated ZB-CaN thin films exhibit half-metallic ferromagnetism. The transition path between the high energy ferromagnetic and the stable nonmagnetic configurations of the ZB-CaN monolayer on Cu(001) are studied by using the nudged elastic band method. We observe a two stages transition and an activation barrier of about 1.18 eV in the minimum energy path of this transition

  10. Determination of 40Ca and 48Ca matter densities by 600 MeV and 1 GeV proton elastic scattering

    International Nuclear Information System (INIS)

    Brissaud, I.; Campi, X.

    1979-02-01

    The 600MeV and 1GeV data of proton elastic scattering on 40 Ca and 48 Ca have been analyzed in the framework of the Glauber model. The matter distributions are extracted from the data in an approximately model-independent form based on a Fourier series expansion. A similar method is used to deduce directly the 48 Ca- 40 Ca neutron density difference

  11. Acupuncture attenuates cognitive deficits and increases pyramidal neuron number in hippocampal CA1 area of vascular dementia rats.

    Science.gov (United States)

    Li, Fang; Yan, Chao-Qun; Lin, Li-Ting; Li, Hui; Zeng, Xiang-Hong; Liu, Yi; Du, Si-Qi; Zhu, Wen; Liu, Cun-Zhi

    2015-04-28

    Decreased cognition is recognized as one of the most severe and consistent behavioral impairments in dementia. Experimental studies have reported that acupuncture may improve cognitive deficits, relieve vascular dementia (VD) symptoms, and increase cerebral perfusion and electrical activity. Multi-infarction dementia was modeled in rats with 3% microemboli saline suspension. Two weeks after acupuncture at Zusanli (ST36), all rats were subjected to a hidden platform trial to test their 3-day spatial memory using the Morris water maze test. To estimate the numbers of pyramidal neuron, astrocytes, and synaptic boutons in hippocampal CA1 area, we adopted an unbiased stereology method to accurately sample and measure the size of cells. We found that acupuncture at ST36 significantly decreased the escape latency of VD rats. In addition, acupuncture significantly increased the pyramidal neuron number in hippocampal CA1 area (P area in any of the groups (P > 0.05). These findings suggest that acupuncture may improve cognitive deficits and increase pyramidal neuron number of hippocampal CA1 area in VD rats.

  12. Density functional calculations of elastic properties of portlandite, Ca(OH)(2)

    DEFF Research Database (Denmark)

    Laugesen, Jakob Lund

    2005-01-01

    The elastic constants of portlandite, Ca(OH)(2), are calculated by use of density functional theory. A lattice optimization of an infinite (periodic boundary conditions) lattice is performed on which strains are applied. The elastic constants are extracted by minimizing Hooke's law of linear...

  13. Deficits in Neurite Density Underlie White Matter Structure Abnormalities in First-Episode Psychosis.

    Science.gov (United States)

    Rae, Charlotte L; Davies, Geoff; Garfinkel, Sarah N; Gabel, Matt C; Dowell, Nicholas G; Cercignani, Mara; Seth, Anil K; Greenwood, Kathryn E; Medford, Nick; Critchley, Hugo D

    2017-11-15

    Structural abnormalities across multiple white matter tracts are recognized in people with early psychosis, consistent with dysconnectivity as a neuropathological account of symptom expression. We applied advanced neuroimaging techniques to characterize microstructural white matter abnormalities for a deeper understanding of the developmental etiology of psychosis. Thirty-five first-episode psychosis patients, and 19 healthy controls, participated in a quantitative neuroimaging study using neurite orientation dispersion and density imaging, a multishell diffusion-weighted magnetic resonance imaging technique that distinguishes white matter fiber arrangement and geometry from changes in neurite density. Fractional anisotropy (FA) and mean diffusivity images were also derived. Tract-based spatial statistics compared white matter structure between patients and control subjects and tested associations with age, symptom severity, and medication. Patients with first-episode psychosis had lower regional FA in multiple commissural, corticospinal, and association tracts. These abnormalities predominantly colocalized with regions of reduced neurite density, rather than aberrant fiber bundle arrangement (orientation dispersion index). There was no direct relationship with active symptoms. FA decreased and orientation dispersion index increased with age in patients, but not control subjects, suggesting accelerated effects of white matter geometry change. Deficits in neurite density appear fundamental to abnormalities in white matter integrity in early psychosis. In the first application of neurite orientation dispersion and density imaging in psychosis, we found that processes compromising axonal fiber number, density, and myelination, rather than processes leading to spatial disruption of fiber organization, are implicated in the etiology of psychosis. This accords with a neurodevelopmental origin of aberrant brain-wide structural connectivity predisposing individuals to

  14. Involvement of nitrergic system of CA1in harmane induced learning and memory deficits.

    Science.gov (United States)

    Nasehi, Mohammad; Piri, Morteza; Abdollahian, Mojgan; Zarrindast, Mohammad Reza

    2013-01-17

    Harmane (HA) is a β-carboline alkaloid derived from the Peganum harmala plant which induces memory impairment. On the other hand some of the investigations showed that β-carboline alkaloids inhibit NO production. Thus, the aim of the present study was to investigate the role of nitrergic system of the dorsal hippocampus (CA1) in HA-induced amnesia in male adult mice. One-trial step-down passive avoidance and hole-board apparatuses were used for the assessment of memory retrieval and exploratory behaviors respectively. The data indicated that pre-training intraperitoneal (i.p.) administration of HA (12 and 16 mg/kg) decreased memory acquisition. Sole pre-training or pre-testing administration of L-NAME, a nitric oxide synthesis inhibitor (5, 10 and 15 μg/mice, intra-CA1) did not alter memory retrieval. On the other hand, pre-training (10 and 15 μg/mice, intra-CA1) and pre-testing (5, 10 μg/mice, intra-CA1) injections of L-NAME restored HA-induced amnesia (16 mg/kg, i.p.). Furthermore, neither sole pre-training nor pre-testing administration of l-arginine, a NO precursor (3, 6 and 9 μg/mice, intra-CA1), altered memory retrieval. In addition, pre-testing (6 and 9 μg/mice, intra-CA1), but not pre-training, injection of l-arginine increased HA-induced amnesia (16 mg/kg, i.p.). These results suggest that the nitrergic system of CA1 is involved in HA-induced amnesia. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Bone mineral density deficits in childhood cancer survivors: Pathophysiology, prevalence, screening, and management

    Directory of Open Access Journals (Sweden)

    Min Jae Kang

    2013-02-01

    Full Text Available As chemotherapy and other sophisticated treatment strategies evolve and the number of survivors of long-term childhood cancer grows, the long-term complications of treatment and the cancer itself are becoming ever more important. One of the most important but often neglected complications is osteoporosis and increased risk of fracture during and after cancer treatment. Acquisition of optimal peak bone mass and strength during childhood and adolescence is critical to preventing osteoporosis later in life. However, most childhood cancer patients have multiple risk factors for bone mineral loss. Cancer itself, malnutrition, decreased physical activity during treatment, chemotherapeutic agents such as steroids, and radiotherapy cause bone mineral deficit. Furthermore, complications such as growth hormone deficiency and musculoskeletal deformity have negative effects on bone metabolism. Low bone mineral density is associated with fractures, skeletal deformity, pain, and substantial financial burden not only for childhood cancer survivors but also for public health care systems. Thus, it is important to monitor bone health in these patients and minimize their risk of developing osteoporosis and fragility fractures later in life.

  16. Nuclear density distributions of 40,42,44,48Ca from elastic scattering of 104 MeV alpha particles

    International Nuclear Information System (INIS)

    Gils, H.J.; Friedman, E.; Majka, Z.

    1979-12-01

    The elastic scattering of 104 MeV α particles from 40 , 42 , 44 , 48 Ca has been analyzed by a single folding model with a density dependent effective interaction. Nuclear density distributions have been extracted using various descriptions including Fourier-Bessel series which distinctly reduces the model dependence of the results and enables realistic estimates of errors. Differences of the density shapes of the Ca-isotopes are well determined showing evidence for a neutron skin in 48 Ca. The resulting root mean square radii are compared to the results obtained from other methods. The sensitivity and limitations of various methods are discussed. (orig.) 891 KBE/orig. 892 BRE

  17. Deficits in synaptic function occur at medial perforant path-dentate granule cell synapses prior to Schaffer collateral-CA1 pyramidal cell synapses in the novel TgF344-Alzheimer's Disease Rat Model.

    Science.gov (United States)

    Smith, Lindsey A; McMahon, Lori L

    2018-02-01

    Alzheimer's disease (AD) pathology begins decades prior to onset of clinical symptoms, and the entorhinal cortex and hippocampus are among the first and most extensively impacted brain regions. The TgF344-AD rat model, which more fully recapitulates human AD pathology in an age-dependent manner, is a next generation preclinical rodent model for understanding pathophysiological processes underlying the earliest stages of AD (Cohen et al., 2013). Whether synaptic alterations occur in hippocampus prior to reported learning and memory deficit is not known. Furthermore, it is not known if specific hippocampal synapses are differentially affected by progressing AD pathology, or if synaptic deficits begin to appear at the same age in males and females in this preclinical model. Here, we investigated the time-course of synaptic changes in basal transmission, paired-pulse ratio, as an indirect measure of presynaptic release probability, long-term potentiation (LTP), and dendritic spine density at two hippocampal synapses in male and ovariectomized female TgF344-AD rats and wildtype littermates, prior to reported behavioral deficits. Decreased basal synaptic transmission begins at medial perforant path-dentate granule cell (MPP-DGC) synapses prior to Schaffer-collateral-CA1 (CA3-CA1) synapses, in the absence of a change in paired-pulse ratio (PPR) or dendritic spine density. N-methyl-d-aspartate receptor (NMDAR)-dependent LTP magnitude is unaffected at CA3-CA1 synapses at 6, 9, and 12months of age, but is significantly increased at MPP-DGC synapses in TgF344-AD rats at 6months only. Sex differences were only observed at CA3-CA1 synapses where the decrease in basal transmission occurs at a younger age in males versus females. These are the first studies to define presymptomatic alterations in hippocampal synaptic transmission in the TgF344-AD rat model. The time course of altered synaptic transmission mimics the spread of pathology through hippocampus in human AD and provides

  18. Density functional theory calculations on alkali and the alkaline Ca atoms adsorbed on graphene monolayers

    International Nuclear Information System (INIS)

    Dimakis, Nicholas; Valdez, Danielle; Flor, Fernando Antonio; Salgado, Andres; Adjibi, Kolade; Vargas, Sarah; Saenz, Justin

    2017-01-01

    Highlights: • Li, K, Na, and Ca graphene interaction is primarily ionic, whereas small covalent interactions also co-exist in these cases. • Van der Waals interactions are revealed by comparing adatom-graphene geometries between 1.4% and 3% adatom coverages and using Grimme corrections. • The Li, K, Na graphene interactions are accurately described by both PBE0 and PBE functionals. For Ca/graphene, the PBE0 functional should not be used. • For Li, K, and Na adsorbed on graphene, adatom-graphene interaction weakens as the adatom coverages increases. • The Ca-graphene interaction strength, which is stronger at high coverages, is opposite to increases in the Ca–4s orbital population. - Abstract: The adsorption of the alkali Li, K, and Na and the alkaline Ca on graphene is studied using periodic density functional theory (DFT) under various adatom coverages. The charge transfers between the adatom and the graphene sheet and the almost unchanged densities-of-states spectra in the energy region near and below the Fermi level support an ionic bond pattern between the adatom and the graphene atoms. However, the presence of small orbital overlap between the metal and the nearest graphene atom is indicative of small covalent bonding. Van der Waals interactions are examined through a semiempirical correction in the DFT functional and by comparing adatom-graphene calculations between 3% and 1.4% adatom coverages. Optimized adatom-graphene geometries identify the preferred adatom sites, whereas the adatom-graphene strength is correlated with the adsorption energy and the adatom distance from the graphene plane. Calculated electronic properties and structural parameters are obtained using hybrid functionals and a generalized gradient approximation functional paired with basis sets of various sizes. We found that due to long range electrostatic forces between the alkali/alkaline adatoms and the graphene monolayer, the adatom-graphene structural and electronic

  19. Density functional theory calculations on alkali and the alkaline Ca atoms adsorbed on graphene monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Dimakis, Nicholas, E-mail: nicholas.dimakis@utrgv.edu [Department of Physics, University of Texas Rio Grande Valley, Edinburg, TX (United States); Valdez, Danielle; Flor, Fernando Antonio; Salgado, Andres; Adjibi, Kolade [Department of Physics, University of Texas Rio Grande Valley, Edinburg, TX (United States); Vargas, Sarah; Saenz, Justin [Robert Vela High School, Edinburg, TX (United States)

    2017-08-15

    Highlights: • Li, K, Na, and Ca graphene interaction is primarily ionic, whereas small covalent interactions also co-exist in these cases. • Van der Waals interactions are revealed by comparing adatom-graphene geometries between 1.4% and 3% adatom coverages and using Grimme corrections. • The Li, K, Na graphene interactions are accurately described by both PBE0 and PBE functionals. For Ca/graphene, the PBE0 functional should not be used. • For Li, K, and Na adsorbed on graphene, adatom-graphene interaction weakens as the adatom coverages increases. • The Ca-graphene interaction strength, which is stronger at high coverages, is opposite to increases in the Ca–4s orbital population. - Abstract: The adsorption of the alkali Li, K, and Na and the alkaline Ca on graphene is studied using periodic density functional theory (DFT) under various adatom coverages. The charge transfers between the adatom and the graphene sheet and the almost unchanged densities-of-states spectra in the energy region near and below the Fermi level support an ionic bond pattern between the adatom and the graphene atoms. However, the presence of small orbital overlap between the metal and the nearest graphene atom is indicative of small covalent bonding. Van der Waals interactions are examined through a semiempirical correction in the DFT functional and by comparing adatom-graphene calculations between 3% and 1.4% adatom coverages. Optimized adatom-graphene geometries identify the preferred adatom sites, whereas the adatom-graphene strength is correlated with the adsorption energy and the adatom distance from the graphene plane. Calculated electronic properties and structural parameters are obtained using hybrid functionals and a generalized gradient approximation functional paired with basis sets of various sizes. We found that due to long range electrostatic forces between the alkali/alkaline adatoms and the graphene monolayer, the adatom-graphene structural and electronic

  20. Critical current density of BiSrCaCuO superconductors: effect of surface barriers

    International Nuclear Information System (INIS)

    Konczykowski, M.; Chikumoto, N.

    1992-01-01

    Effects of surface barriers on vortex motion in BiSrCaCuO-2212 high-temperature superconducting crystals is summarized. Characteristic features of this phenomenon appear in the hysteresis loop (shape of its ascending and descending branches), in the effect of 2.5 MeV electron irradiation, and in flux creep measurements (magnetization dependence to the crystal lateral dimension, size of the flux-creep barrier and the crossover as a function of temperature and time persistent current density). (A.B.). 25 refs., 3 figs

  1. High-Order Ca(II)-Chloro Complexes in Mixed CaCl2-LiCl Aqueous Solution: Insights from Density Functional Theory and Molecular Dynamics Simulations.

    Science.gov (United States)

    Wang, Yu-Lin; Wang, Ying; Yi, Hai-Bo

    2016-07-21

    In this study, the structural characteristics of high-coordinated Ca-Cl complexes present in mixed CaCl2-LiCl aqueous solution were investigated using density functional theory (DFT) and molecular dynamics (MD) simulations. The DFT results show that [CaClx](2-x) (x = 4-6) clusters are quite unstable in the gas phase, but these clusters become metastable when hydration is considered. The MD simulations show that high-coordinated Ca-chloro complexes are possible transient species that exist for up to nanoseconds in concentrated (11.10 mol·kg(-1)) Cl(-) solution at 273 and 298 K. As the temperature increases to 423 K, these high-coordinated structures tend to disassociate and convert into smaller clusters and single free ions. The presence of high-order Ca-Cl species in concentrated LiCl solution can be attributed to their enhanced hydration shell and the inadequate hydration of ions. The probability of the [CaClx](2-x)aq (x = 4-6) species being present in concentrated LiCl solution decreases greatly with increasing temperature, which also indicates that the formation of the high-coordinated Ca-Cl structure is related to its hydration characteristics.

  2. Fear extinction deficits following acute stress associate with increased spine density and dendritic retraction in basolateral amygdala neurons.

    Science.gov (United States)

    Maroun, Mouna; Ioannides, Pericles J; Bergman, Krista L; Kavushansky, Alexandra; Holmes, Andrew; Wellman, Cara L

    2013-08-01

    Stress-sensitive psychopathologies such as post-traumatic stress disorder are characterized by deficits in fear extinction and dysfunction of corticolimbic circuits mediating extinction. Chronic stress facilitates fear conditioning, impairs extinction, and produces dendritic proliferation in the basolateral amygdala (BLA), a critical site of plasticity for extinction. Acute stress impairs extinction, alters plasticity in the medial prefrontal cortex-to-BLA circuit, and causes dendritic retraction in the medial prefrontal cortex. Here, we examined extinction learning and basolateral amygdala pyramidal neuron morphology in adult male rats following a single elevated platform stress. Acute stress impaired extinction acquisition and memory, and produced dendritic retraction and increased mushroom spine density in basolateral amygdala neurons in the right hemisphere. Unexpectedly, irrespective of stress, rats that underwent fear and extinction testing showed basolateral amygdala dendritic retraction and altered spine density relative to non-conditioned rats, particularly in the left hemisphere. Thus, extinction deficits produced by acute stress are associated with increased spine density and dendritic retraction in basolateral amygdala pyramidal neurons. Furthermore, the finding that conditioning and extinction as such was sufficient to alter basolateral amygdala morphology and spine density illustrates the sensitivity of basolateral amygdala morphology to behavioral manipulation. These findings may have implications for elucidating the role of the amygdala in the pathophysiology of stress-related disorders. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  3. Fear extinction deficits following acute stress associate with increased spine density and dendritic retraction in basolateral amygdala neurons

    Science.gov (United States)

    Maroun, Mouna; Ioannides, Pericles J.; Bergman, Krista L.; Kavushansky, Alexandra; Holmes, Andrew; Wellman, Cara L.

    2013-01-01

    Stress-sensitive psychopathologies such as post-traumatic stress disorder are characterized by deficits in fear extinction and dysfunction of corticolimbic circuits mediating extinction. Chronic stress facilitates fear conditioning, impairs extinction, and produces dendritic proliferation in the basolateral amygdala (BLA), a critical site of plasticity for extinction. Acute stress impairs extinction, alters plasticity in the medial prefrontal cortex-to-BLA circuit, and causes dendritic retraction in the medial prefrontal cortex. Here, we examined extinction learning and basolateral amygdala pyramidal neuron morphology in adult male rats following a single elevated platform stress. Acute stress impaired extinction acquisition and memory, and produced dendritic retraction and increased mushroom spine density in basolateral amygdala neurons in the right hemisphere. Unexpectedly, irrespective of stress, rats that underwent fear and extinction testing showed basolateral amygdala dendritic retraction and altered spine density relative to non-conditioned rats, particularly in the left hemisphere. Thus, extinction deficits produced by acute stress are associated with increased spine density and dendritic retraction in basolateral amygdala pyramidal neurons. Furthermore, the finding that conditioning and extinction as such was sufficient to alter basolateral amygdala morphology and spine density illustrates the sensitivity of basolateral amygdala morphology to behavioral manipulation. These findings may have implications for elucidating the role of the amygdala in the pathophysiology of stress-related disorders. PMID:23714419

  4. Low dopamine D5 receptor density in hippocampus in an animal model of attention-deficit/hyperactivity disorder (ADHD)

    DEFF Research Database (Denmark)

    Medin, T; Rinholm, J E; Owe, S G

    2013-01-01

    A state of low dopaminergic activity has been implicated in attention-deficit/hyperactivity disorder (ADHD). The clinical symptoms of ADHD include inattention, impulsivity and hyperactivity, as well as impaired learning; dopaminergic modulation of the functions in the hippocampus is important......, indicating a reduced reservoir for insertion of receptors into the plasma membrane. DRs are important for long-term potentiation and long-term depression, hence the deficit may contribute to the learning difficulties in individuals with the diagnosis of ADHD....... to both learning and memory. To determine dopamine receptor (DR) density in a well-established animal model for ADHD, we quantified the dopamine D5 receptors in the hippocampus in the spontaneously hypertensive rat. We used immunofluorescence microscopy and immunogold electron microscopy to quantify...

  5. Effects of Recent Minimum Temperature and Water Deficit Increases on Pinus pinaster Radial Growth and Wood Density in Southern Portugal

    Science.gov (United States)

    Kurz-Besson, Cathy B.; Lousada, José L.; Gaspar, Maria J.; Correia, Isabel E.; David, Teresa S.; Soares, Pedro M. M.; Cardoso, Rita M.; Russo, Ana; Varino, Filipa; Mériaux, Catherine; Trigo, Ricardo M.; Gouveia, Célia M.

    2016-01-01

    Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events. To address this question, tree-ring width and density chronologies were built for a Pinus pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011. We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster’s vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster’s production capacity and quality in response to more arid conditions in the near future in the region. PMID:27570527

  6. Effects of Recent Minimum Temperature and Water Deficit Increases on Pinus pinaster Radial Growth and Wood Density in Southern Portugal.

    Science.gov (United States)

    Kurz-Besson, Cathy B; Lousada, José L; Gaspar, Maria J; Correia, Isabel E; David, Teresa S; Soares, Pedro M M; Cardoso, Rita M; Russo, Ana; Varino, Filipa; Mériaux, Catherine; Trigo, Ricardo M; Gouveia, Célia M

    2016-01-01

    Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events. To address this question, tree-ring width and density chronologies were built for a Pinus pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011. We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster's vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster's production capacity and quality in response to more arid conditions in the near future in the region.

  7. Phase transitions of titanite CaTiSiO5 from density functional perturbation theory

    Science.gov (United States)

    Malcherek, Thomas; Fischer, Michael

    2018-02-01

    Phonon dispersion of titanite CaTiSiO5 has been calculated using the variational density functional perturbation theory. The experimentally known out-of-center distortion of the Ti atom is confirmed. The distortion is associated with a Bu mode that is unstable for wave vectors normal to the octahedral chain direction of the C 2 /c aristotype structure. The layer of wave vectors with imaginary mode frequencies also comprises the Brillouin zone boundary point Y (0 ,1 ,0 ) , which is critical for the transition to the P 21/c ground-state structure. The phonon branch equivalent to the imaginary branch of the titanite aristotype is found to be stable in malayaite CaSnSiO5. The unstable phonon mode in titanite leads to the formation of transoriented short and long Ti-O1 bonds. The Ti as well as the connecting O1 atom exhibit strongly anomalous Born effective charges along the octahedral chain direction [001], indicative of the strong covalency in this direction. Accordingly and in contrast to malayaite, LO-TO splitting is very large in titanite. In the C 2 /c phase of titanite, the Ti-O1-Ti distortion chain is disordered with respect to neighboring distortion chains, as all chain configurations are equally unstable along the phonon branch. This result is in agreement with diffuse x-ray scattering in layers normal to the chain direction that is observed at temperatures close to the P 21/c to C 2 /c transition temperature and above. The resulting dynamic chains of correlated Ti displacements are expected to order in two dimensions to yield the P 21/c ground-state structure of titanite.

  8. Reduced density and altered regulation of rat atrial L-type Ca2+ current in heart failure.

    Science.gov (United States)

    Bond, Richard C; Bryant, Simon M; Watson, Judy J; Hancox, Jules C; Orchard, Clive H; James, Andrew F

    2017-03-01

    Constitutive regulation by PKA has recently been shown to contribute to L-type Ca 2+ current ( I CaL ) at the ventricular t-tubule in heart failure. Conversely, reduction in constitutive regulation by PKA has been proposed to underlie the downregulation of atrial I CaL in heart failure. The hypothesis that downregulation of atrial I CaL in heart failure involves reduced channel phosphorylation was examined. Anesthetized adult male Wistar rats underwent surgical coronary artery ligation (CAL, N =10) or equivalent sham-operation (Sham, N =12). Left atrial myocytes were isolated ~18 wk postsurgery and whole cell currents recorded (holding potential=-80 mV). I CaL activated by depolarizing pulses to voltages from -40 to +50 mV were normalized to cell capacitance and current density-voltage relations plotted. CAL cell capacitances were ~1.67-fold greater than Sham ( P ≤ 0.0001). Maximal I CaL conductance ( G max ) was downregulated more than 2-fold in CAL vs. Sham myocytes ( P 50% more effectively in CAL than in Sham so that differences in I CaL density were abolished. Differences between CAL and Sham G max were not abolished by calyculin A (100 nmol/l), suggesting that increased protein dephosphorylation did not account for I CaL downregulation. Treatment with either H-89 (10 μmol/l) or AIP (5 μmol/l) had no effect on basal currents in Sham or CAL myocytes, indicating that, in contrast to ventricular myocytes, neither PKA nor CaMKII regulated basal I CaL Expression of the L-type α 1C -subunit, protein phosphatases 1 and 2A, and inhibitor-1 proteins was unchanged. In conclusion, reduction in PKA-dependent regulation did not contribute to downregulation of atrial I CaL in heart failure. NEW & NOTEWORTHY Whole cell recording of L-type Ca 2+ currents in atrial myocytes from rat hearts subjected to coronary artery ligation compared with those from sham-operated controls reveals marked reduction in current density in heart failure without change in channel subunit

  9. ERK1/2 Activation Is Necessary for BDNF to Increase Dendritic Spine Density in Hippocampal CA1 Pyramidal Neurons

    Science.gov (United States)

    Alonso, Mariana; Medina, Jorge H.; Pozzo-Miller, Lucas

    2004-01-01

    Brain-derived neurotrophic factor (BDNF) is a potent modulator of synaptic transmission and plasticity in the CNS, acting both pre- and postsynaptically. We demonstrated recently that BDNF/TrkB signaling increases dendritic spine density in hippocampal CA1 pyramidal neurons. Here, we tested whether activation of the prominent ERK (MAPK) signaling…

  10. Density functional study of CaN monolayer on Si(001)

    Energy Technology Data Exchange (ETDEWEB)

    Saati asr, Maryam; Zahedifar, Maedeh; Hashemifar, S. Javad; Akbarzadeh, Hadi

    2016-01-01

    In this work, the first-principles computations are performed to study the structural and magnetic properties of CaN/Si(001) interface. Bulk CaN in the zinc-blende (ZB) structure is argued to be an ionic magnetic compound with a total spin moment of 1 μ{sub B} per formula unit, originated from the p electrons of N ions. Various interface configurations of a ZB CaN monolayer on Si (001) surface are investigated and the lowest energy and the highest spin polarized interfaces are extracted. Then the minimum energy path between the lowest energy and the highest spin polarized interfaces are calculated by using the nudged elastic band method and it is argued that both these systems are unstable toward a nonmagnetic interface with a rock–salt arrangement of Ca and N atoms. - Highlights: • Ab-initio studies are done on various structures of CaN monolayer on Si (001). • The lowest energy system was found to be the N-top configuration interface, while the highest spin polarization was observed in the Ca-hollow termination. • Both Ca-hollow and N-top are unstable toward a nonmagnetic rock–salt CaN monolayer on silicon surface. • Realization of a magnetic CaN/Si (001) interface likely requires some buffer layer on silicon surface, prior to the thin film deposition.

  11. Density functional study of CaN monolayer on Si(001)

    International Nuclear Information System (INIS)

    Saati asr, Maryam; Zahedifar, Maedeh; Hashemifar, S. Javad; Akbarzadeh, Hadi

    2016-01-01

    In this work, the first-principles computations are performed to study the structural and magnetic properties of CaN/Si(001) interface. Bulk CaN in the zinc-blende (ZB) structure is argued to be an ionic magnetic compound with a total spin moment of 1 μ_B per formula unit, originated from the p electrons of N ions. Various interface configurations of a ZB CaN monolayer on Si (001) surface are investigated and the lowest energy and the highest spin polarized interfaces are extracted. Then the minimum energy path between the lowest energy and the highest spin polarized interfaces are calculated by using the nudged elastic band method and it is argued that both these systems are unstable toward a nonmagnetic interface with a rock–salt arrangement of Ca and N atoms. - Highlights: • Ab-initio studies are done on various structures of CaN monolayer on Si (001). • The lowest energy system was found to be the N-top configuration interface, while the highest spin polarization was observed in the Ca-hollow termination. • Both Ca-hollow and N-top are unstable toward a nonmagnetic rock–salt CaN monolayer on silicon surface. • Realization of a magnetic CaN/Si (001) interface likely requires some buffer layer on silicon surface, prior to the thin film deposition.

  12. New 3D gas density maps of NaI and CaII interstellar absorption within 300 pc

    Science.gov (United States)

    Welsh, B. Y.; Lallement, R.; Vergely, J.-L.; Raimond, S.

    2010-02-01

    Aims: We present new high resolution (R > 50 000) absorption measurements of the NaI doublet (5889-5895 Å) along 482 nearby sight-lines, in addition to 807 new measurements of the CaII K (3933 Å) absorption line. We have combined these new data with previously reported measurements to produce a catalog of absorptions towards a total of 1857 early-type stars located within 800 pc of the Sun. Using these data we have determined the approximate 3-dimensional spatial distribution of neutral and partly ionized interstellar gas density within a distance-cube of 300 pc from the Sun. Methods: All newly recorded spectra were analyzed by means of a multi-component line profile-fitting program, in most cases using simultaneous fits to the line doublets. Normalized absorption profiles were fitted by varying the velocity, doppler width and column density for all intervening interstellar clouds. The resulting total column densities were then used in conjunction with the Hipparcos distances of the target stars to construct inversion maps of the 3D spatial density distribution of the NaI and CaII bearing gas. Results: A plot of the equivalent width of NaI versus distance reveals a wall of neutral gas at ~80 pc that can be associated with the boundary wall to the central rarefied Local Cavity region. In contrast, a similar plot for the equivalent width of CaII shows no sharply increasing absorption at 80 pc, but instead we observe a slowly increasing value of CaII equivalent width with increasing sight-line distance sampled. Low values for the volume density of NaI (nNaI values in the range 10-8 >nNaI > 10-10 cm-3 are found for sight-lines with distance >300 pc. Both high and low values of the volume density of CaII (nCaII) are found for sight-lines 100 pc a value of nCaII ~ 10-9 cm-3 is typical for most sight-lines, indicating that the distribution of CaII bearing gas is fairly uniform throughout the general ISM. Our three maps of the 3D spatial distribution of local neutral Na

  13. Using reference nutrient density goals with food balance sheet data to identify likely micronutrient deficits for fortification planning in countries in the Western Pacific region.

    Science.gov (United States)

    Gibson, Rosalind S; Cavalli-Sforza, Tommaso

    2012-09-01

    Collection of nationwide food consumption data at the individual level is the preferred option for planning fortification programs. However, such data are seldom collected in low-income countries. In contrast, Food Balance Sheets (FBS), published annually for approximately 180 countries, may provide a source of national data for program planning. To explore the use of micronutrient densities from FBS data to identify likely deficits for eight micronutrients in national diets. Micronutrient densities in the daily available food supply per capita were calculated from the micronutrient contents of 95 food commodities in 17 Western Pacific Region countries. Densities were compared with reference nutrient density goals developed to ensure that at least 95% of individuals, irrespective of life-stage group, are likely to have adequate intakes. Of the eight micronutrients, Cambodia and Korea D.P.R. had likely deficits for six; China, Fiji, Kiribati, Korea Republic, Lao P.D.R., Philippines, Solomon Islands, Vanuatu, and Viet Nam had likely deficits for five; Brunei Darussalam, Malaysia, Mongolia, New Zealand, and Papua New Guinea had likely deficits for four; and New Caledonia had likely deficits for three. The most frequent deficits were for iron, zinc, and calcium (all countries), followed by vitamin B2 and vitamin A (n = 13), vitamin B1 (n = 2), and vitamin B12 (n = 1). The nutrient density approach could be applied to FBS data for ranking countries according to likely micronutrient deficits, but it provides no information on distribution of nutrient supply for fortification program planning. The approach described here could be applied to data from Household Consumption and Expenditures Surveys (HCES) to characterize households at greatest risk.

  14. Maternal exposure of rats to nicotine via infusion during gestation produces neurobehavioral deficits and elevated expression of glial fibrillary acidic protein in the cerebellum and CA1 subfield in the offspring at puberty

    International Nuclear Information System (INIS)

    Abdel-Rahman, Ali; Dechkovskaia, Anjelika M.; Sutton, Jazmine M.; Chen, Wei-Chung; Guan, Xiangrong; Khan, Wasiuddin A.; Abou-Donia, Mohamed B.

    2005-01-01

    Maternal smoking during pregnancy is known to be a significant contributor to developmental neurological health problems in the offspring. In animal studies, nicotine treatment via injection during gestation has been shown to produce episodic hypoxia in the developing fetus. Nicotine delivery via mini osmotic pump, while avoiding effects due to hypoxia-ischemia, it also provides a steady level of nicotine in the plasma. In the present study timed-pregnant Sprague-Dawley rats (300-350 g) were treated with nicotine (3.3 mg/kg, in bacteriostatic water via s.c. implantation of mini osmotic pump) from gestational days (GD) 4-20. Control animals were treated with bacteriostatic water via s.c. implantation of mini osmotic pump. Offspring on postnatal day (PND) 30 and 60, were evaluated for changes in the ligand binding for various types of nicotinic acetylcholine receptors and neuropathological alterations. Neurobehavioral evaluations for sensorimotor functions, beam-walk score, beam-walk time, incline plane and grip time response were carried out on PND 60 offspring. Beam-walk time and forepaw grip time showed significant impairments in both male and female offspring. Ligand binding densities for [ 3 H]epibatidine, [ 3 H]cytisine and [ 3 H]α-bungarotoxin did not show any significant changes in nicotinic acetylcholine receptors subtypes in the cortex at PND 30 and 60. Histopathological evaluation using cresyl violet staining showed significant decrease in surviving Purkinje neurons in the cerebellum and a decrease in surviving neurons in the CA1 subfield of hippocampus on PND 30 and 60. An increase in glial fibrillary acidic protein (GFAP) immuno-staining was observed in cerebellum white matter as well as granular cell layer of cerebellum and the CA1 subfield of hippocampus on PND 30 and 60 of both male and female offspring. These results indicate that maternal exposure to nicotine produces significant neurobehavioral deficits, a decrease in the surviving neurons and an

  15. Neutron densities and the single particle structure of several even-even nuclei from 40Ca to 208Pb

    International Nuclear Information System (INIS)

    Ray, L.; Hodgson, P.E.

    1979-01-01

    Previously developed techniques which sum the squares of proton single particle wave functions to obtain nuclear charge densities are applied to the study of neutron distributions in /sup 40,48/Ca, /sup 58,64/Ni, /sup 116,124/Sn, and 208 Pb by comparing to those neutron densities deduced from 800 MeV proton elastic scattering data. The proton and neutron single particle wave functions are derived from a one-body, nonlocal Woods-Saxon binding potential whose parameters are adjusted to give the experimental single particle energies. Empirical spectroscopic factors determine the appropriate occupation probabilities for the single particle levels near the Fermi surface. Proper attention is given to nonorthogonality problems and to the removal of the spurious center-of-mass motion. These semiphenomenological neutron densities are compared to the predictions of the density matrix expansion variant of Hartree-Fock theory and to densities which are empirically deduced from recent 800 MeV polarized proton elastic scattering data. These ''experimental'' neutron distributions are obtained from approximate second order Kerman, McManus, and Thaler optical potential analyses using essentially ''model independent'' neutron densities. Qualitatively good agreement is obtained between the semiphenomenological neutron densities computed here, the density matrix expansion predictions, and the empirical results

  16. Novel nootropic drug sunifiram improves cognitive deficits via CaM kinase II and protein kinase C activation in olfactory bulbectomized mice.

    Science.gov (United States)

    Moriguchi, Shigeki; Tanaka, Tomoya; Tagashira, Hideaki; Narahashi, Toshio; Fukunaga, Kohji

    2013-04-01

    Alzheimer's disease (AD) shows degeneration of the cholinergic system in the medial septum, thereby eliciting down-regulation of the olfactory function in patients. We have previously reported that olfactory bulbectomized (OBX) mice show hippocampus-dependent memory impairment as assessed by memory-related behavioral tasks and hippocampal long-term potentiation (LTP). In the present study, we focused whether novel pyrrolidone nootropic drug sunifiram improves both memory impairment and depression observed in OBX mice. OBX mice were administered once a day for 7-12 days with sunifiram (0.01-1.0mg/kg p.o.) from 10 days after operation with or without gavestinel (10mg/kg i.p.), which is glycine-binding site inhibitor of N-methyl-d-aspartate receptor (NMDAR). The spatial reference memory assessed by Y-maze and short-term memory assessed by novel object recognition task were significantly improved by sunifiram treatment in OBX mice. Sunifiram also restored hippocampal LTP injured in OBX mice without treatment with gavestinel. By contrast, sunifiram treatment did not ameliorate the depressive behaviors assessed by tail suspension task in OBX mice. Notably, sunifiram treatment restored CaMKIIα (Thr-286) autophosphorylation and GluR1 (Ser-831) phosphorylation in the hippocampal CA1 region from OBX mice to the levels of control mice. Likewise, sunifiram treatment improved PKCα (Ser-657) autophosphorylation and NR1 (Ser-896) phosphorylation to the control levels. Stimulation of CaMKII and PKC autophosphorylation by sunifiram was significantly inhibited by pre-treatment with gavestinel. However, sunifiram treatment did not affect the phosphorylation of CaMKIV (Thr-196) and ERK. Taken together, sunifiram ameliorates OBX-induced deficits of memory-related behaviors and impaired LTP in the hippocampal CA1 region via stimulation of glycine-binding site of NMDAR. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. High-density expression of Ca2+-permeable ASIC1a channels in NG2 glia of rat hippocampus.

    Directory of Open Access Journals (Sweden)

    Yen-Chu Lin

    Full Text Available NG2 cells, a fourth type of glial cell in the mammalian CNS, undergo reactive changes in response to a wide variety of brain insults. Recent studies have demonstrated that neuronally expressed acid-sensing ion channels (ASICs are implicated in various neurological disorders including brain ischemia and seizures. Acidosis is a common feature of acute neurological conditions. It is postulated that a drop in pH may be the link between the pathological process and activation of NG2 cells. Such postulate immediately prompts the following questions: Do NG2 cells express ASICs? If so, what are their functional properties and subunit composition? Here, using a combination of electrophysiology, Ca2+ imaging and immunocytochemistry, we present evidence to demonstrate that NG2 cells of the rat hippocampus express high density of Ca2+-permeable ASIC1a channels compared with several types of hippocampal neurons. First, nucleated patch recordings from NG2 cells revealed high density of proton-activated currents. The magnitude of proton-activated current was pH dependent, with a pH for half-maximal activation of 6.3. Second, the current-voltage relationship showed a reversal close to the equilibrium potential for Na+. Third, psalmotoxin 1, a blocker specific for the ASIC1a channel, largely inhibited proton-activated currents. Fourth, Ca2+ imaging showed that activation of proton-activated channels led to an increase of [Ca2+]i. Finally, immunocytochemistry showed co-localization of ASIC1a and NG2 proteins in the hippocampus. Thus the acid chemosensor, the ASIC1a channel, may serve for inducing membrane depolarization and Ca2+ influx, thereby playing a crucial role in the NG2 cell response to injury following ischemia.

  18. EnviroAtlas - Fresno, CA - Estimated Intersection Density of Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...

  19. Effect of intrahippocampal CA1 injection of insulin on spatial learning and memory deficits in diabetic rats

    Directory of Open Access Journals (Sweden)

    Golbarg Ghiasi

    2011-03-01

    Full Text Available Background: Diabetes mellitus is one of the most important diseases in all over the world. Insulin and its receptor are found in specific area of CNS with a variety of regions-specific functions different from its role in direct glucose regulation in the periphery. The hippocampus and cerebral cortex distributed insulin and insulin receptor has been shown to be involved in brain cognitive functions. Previous studies about the effect of insulin on memory in diabetes are controversial and further investigation is necessary.Methods: Seventy male NMRI rats (250-300 g were randomly divided into control, diabetic, saline-saline, saline-insulin (12, 18 or 24 mU, diabetic-saline, diabetic-insulin (12, 18 or 24 mU groups. Diabetes was induced by streptozotocin (65 mg/kg, ip. Saline or insulin were injected bilaterally (1 µl/rat into CA1 region of hippocampus during 1 min. Thirty minutes later, water maze training was performed.Results: Insulin had a dose dependent effect. The spatial learning and memory were impaired with diabetes, and improved by insulin. Escape latency and swimming distance in a water maze in insulin treated animals were significantly lower (P<0.05 than control and diabetic groups. Percentage of time spent by animals in a target quarter in probe trial session showed a significant difference among groups. This difference was significant between insulin treated and the other groups (P<0.05.Conclusions: Our findings suggest that injection of insulin into hippocampal CA1 area may have a dose-dependent effect on spatial learning and memory in diabetic rats.

  20. Dim light at night provokes depression-like behaviors and reduces CA1 dendritic spine density in female hamsters.

    Science.gov (United States)

    Bedrosian, Tracy A; Fonken, Laura K; Walton, James C; Haim, Abraham; Nelson, Randy J

    2011-08-01

    The prevalence of major depression has increased in recent decades; however, the underlying causes of this phenomenon remain unspecified. One environmental change that has coincided with elevated rates of depression is increased exposure to artificial light at night. Shift workers and others chronically exposed to light at night are at increased risk of mood disorders, suggesting that nighttime illumination may influence brain mechanisms mediating affect. We tested the hypothesis that exposure to dim light at night may impact affective responses and alter morphology of hippocampal neurons. Ovariectomized adult female Siberian hamsters (Phodopus sungorus) were housed for 8 weeks in either a light/dark cycle (LD) or a light/dim light cycle (DM), and then behavior was assayed. DM-hamsters displayed more depression-like responses in the forced swim and the sucrose anhedonia tests compared with LD-hamsters. Conversely, in the elevated plus maze DM-hamsters reduced anxiety-like behaviors. Brains from the same animals were processed using the Golgi-Cox method and hippocampal neurons within CA1, CA3, and the dentate gyrus were analyzed for morphological characteristics. In CA1, DM-hamsters significantly reduced dendritic spine density on both apical and basilar dendrites, an effect which was not mediated by baseline cortisol, as concentrations were equivalent between groups. These results demonstrate dim light at night is sufficient to reduce synaptic spine connections to CA1. Importantly, the present results suggest that night-time low level illumination, comparable to levels that are pervasive in North America and Europe, may contribute to the increasing prevalence of mood disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Dopamine transporter density of the basal ganglia in children with attention deficit hyperactivity disorder assessed with I-123 IPT SPECT

    International Nuclear Information System (INIS)

    Ryu, Won Gee; Kim, Tae Hoon; Ryu, Young Hoon; Yun, Mi Jin; Lee, Jong Doo; Cheon, Keun Ah; Chi, Dae Yoon; Kim, Jong Ho; Choi, Tae Hyun

    2003-01-01

    Attention deficit hyperactivity disorder (ADHD) has been known as psychiatric disorder in childhood associated with dopamine dysregulation. In present study, we investigated changes in dopamine transporter (DAT) density of the basal ganglias using I-123 N-(3-iodopropen-2-yl) -2-carbomethoxy-3beta-(4-chlorphenyl) tropane (I-123 IPT) SPECT in children with ADHD before and after methylphenidate treatment. Nine drug-naive children with ADHD and seven normal children were included in the study. We performed brain SPECT two hours after the intravenous administration of I-123 IPT and made both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of specific/nonspecific DAT binding ratios in the basal ganglia. All children with ADHD reperformed (123I)IPT SPECT after treatment with methylphenidate (0.7mg/kg/d) during about 8 weeks. SPECT data reconstructed for the assessment of specific/nonspecific DAT binding ratio of the basal ganglia were compared between before and after treatment methyphenidate. We investigated correlation between the change of ADHD symptom severity assessed with ADHD rating scale-IV and specific/nonspecific DAT binding ratio of basal ganglia. Children with ADHD had a significantly greater specific/nonspecific DAT binding ratio of the basal ganglia comparing to normal children (Right : z = 2.057, p = 0.041 ; Left : z = 2.096, p = 0.032). Under treatment with methylphenidate in all children with ADHD, specific/nonspecific DAT binding ratio of both ganglia decreased significantly greater than before treatment with methylphenidate (Right : t = 3.239, p = 0.018 ; Left : t = 3.133, p 0.020). However, no significant correlation between the change of ADHD symptom severity scores and specific/nonspecific DAT binding ratio of the basal ganglia were found. These findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD

  2. Dopamine transporter density of the basal ganglia in children with attention deficit hyperactivity disorder assessed with I-123 IPT SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Won Gee; Kim, Tae Hoon; Ryu, Young Hoon; Yun, Mi Jin; Lee, Jong Doo; Cheon, Keun Ah [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of); Chi, Dae Yoon [College of Medicine, Inha Univ., Incheon (Korea, Republic of); Kim, Jong Ho; Choi, Tae Hyun [School of Medicine, Gachon Univ., Gachon (Korea, Republic of)

    2003-08-01

    Attention deficit hyperactivity disorder (ADHD) has been known as psychiatric disorder in childhood associated with dopamine dysregulation. In present study, we investigated changes in dopamine transporter (DAT) density of the basal ganglias using I-123 N-(3-iodopropen-2-yl) -2-carbomethoxy-3beta-(4-chlorphenyl) tropane (I-123 IPT) SPECT in children with ADHD before and after methylphenidate treatment. Nine drug-naive children with ADHD and seven normal children were included in the study. We performed brain SPECT two hours after the intravenous administration of I-123 IPT and made both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of specific/nonspecific DAT binding ratios in the basal ganglia. All children with ADHD reperformed (123I)IPT SPECT after treatment with methylphenidate (0.7mg/kg/d) during about 8 weeks. SPECT data reconstructed for the assessment of specific/nonspecific DAT binding ratio of the basal ganglia were compared between before and after treatment methyphenidate. We investigated correlation between the change of ADHD symptom severity assessed with ADHD rating scale-IV and specific/nonspecific DAT binding ratio of basal ganglia. Children with ADHD had a significantly greater specific/nonspecific DAT binding ratio of the basal ganglia comparing to normal children (Right : z = 2.057, p = 0.041 ; Left : z = 2.096, p = 0.032). Under treatment with methylphenidate in all children with ADHD, specific/nonspecific DAT binding ratio of both ganglia decreased significantly greater than before treatment with methylphenidate (Right : t = 3.239, p = 0.018 ; Left : t = 3.133, p 0.020). However, no significant correlation between the change of ADHD symptom severity scores and specific/nonspecific DAT binding ratio of the basal ganglia were found. These findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD.

  3. Absolute emission current density of O- from 12CaO·7Al2O3 crystal

    International Nuclear Information System (INIS)

    Li, Q.X.; Hayashi, K.; Nishioka, M.; Kashiwagi, H.; Hirano, M.; Torimoto, Y.; Hosono, H.; Sadakata, M.

    2002-01-01

    Strong and high purity O - negative ion emission has been observed from a synthesized crystal 12CaO·7Al 2 O 3 surface. A μA/cm2-level O - emission from this material has been achieved at the surface temperature of 800 deg. C and the extraction field over 1000 V/cm, which is about three orders of magnitude higher than the current density emitted from the Y 2 O 3 -stabilized ZrO 2 electrolyte surface. The strong emissivity of this material, as well as easy and economical fabrication, may provide a useful tool to generate the O - negative ion, which is expected to be one of the most important radicals for chemical syntheses and material modifications

  4. The Effects of CaCO3 Coated Wood Free Paper Usage as Filler on Water Absorption, Mechanical and Thermal Properties of Cellulose-High Density Polyethylene Composites

    Directory of Open Access Journals (Sweden)

    Emrah PEŞMAN

    2016-11-01

    Full Text Available In this study some physical, mechanical and thermal characteristics of high density polyethylene (HDPE and CaCO3 coated/pigmented wood free paper fiber composites were investigated. The fillers used in this study were uncoated cellulose, 5.8 %, 11.5 %, 16.5 % and 23.1 % CaCO3 coated wood free paper fibers. Each filler type was mixed with HDPE at 40% by weight fiber loading. In this case, the ratio of CaCO3 in plastic composites were calculated as 0 %, 2.3 %, 4.6 %, 6.6 % and 9.2 % respectively. Increased CaCO3 ratio improved the moisture resistant, flexural and tensile strength of cellulose-HDPE composites. However, the density of the cellulose-HDPE composites increased with CaCO3 addition. Energy Dispersive Spectroscopy on Scanning Electron Microscope analysis demonstrated the uniform distribution of CaCO3 and cellulose fiber in plastic matrix. In addition, the thermal properties of fiber plastic composites were investigated. The results of Differential scanning calorimetry analysis revealed that the crystallinity of the samples decreased with increasing CaCO3 content. Consequently, this work showed that CaCO3 coated waste paper fibers could be used as reinforcing filler against water absorption in thermoplastic matrix.DOI: http://dx.doi.org/10.5755/j01.ms.22.4.14222

  5. Hybrid Density Functional Study of the Local Structures and Energy Levels of CaAl2O4:Ce3.

    Science.gov (United States)

    Lou, Bibo; Jing, Weiguo; Lou, Liren; Zhang, Yongfan; Yin, Min; Duan, Chang-Kui

    2018-05-03

    First-principles calculations were carried out for the electronic structures of Ce 3+ in calcium aluminate phosphors, CaAl 2 O 4 , and their effects on luminescence properties. Hybrid density functional approaches were used to overcome the well-known underestimation of band gaps of conventional density functional approaches and to calculate the energy levels of Ce 3+ ions more accurately. The obtained 4f-5d excitation and emission energies show good consistency with measured values. A detailed energy diagram of all three sites is obtained, which explains qualitatively all of the luminescent phenomena. With the results of energy levels calculated by combining the hybrid functional of Heyd, Scuseria, and Ernzerhof (HSE06) and the constraint occupancy approach, we are able to construct a configurational coordinate diagram to analyze the processes of capture of a hole or an electron and luminescence. This approach can be applied for systematic high-throughput calculations in predicting Ce 3+ activated luminescent materials with a moderate computing requirement.

  6. Wheel running from a juvenile age delays onset of specific motor deficits but does not alter protein aggregate density in a mouse model of Huntington's disease

    Directory of Open Access Journals (Sweden)

    Spires Tara L

    2008-04-01

    Full Text Available Abstract Background Huntington's disease (HD is a neurodegenerative disorder predominantly affecting the cerebral cortex and striatum. Transgenic mice (R6/1 line, expressing a CAG repeat encoding an expanded polyglutamine tract in the N-terminus of the huntingtin protein, closely model HD. We have previously shown that environmental enrichment of these HD mice delays the onset of motor deficits. Furthermore, wheel running initiated in adulthood ameliorates the rear-paw clasping motor sign, but not an accelerating rotarod deficit. Results We have now examined the effects of enhanced physical activity via wheel running, commenced at a juvenile age (4 weeks, with respect to the onset of various behavioral deficits and their neuropathological correlates in R6/1 HD mice. HD mice housed post-weaning with running wheels only, to enhance voluntary physical exercise, have delayed onset of a motor co-ordination deficit on the static horizontal rod, as well as rear-paw clasping, although the accelerating rotarod deficit remains unaffected. Both wheel running and environmental enrichment rescued HD-induced abnormal habituation of locomotor activity and exploratory behavior in the open field. We have found that neither environment enrichment nor wheel running ameliorates the shrinkage of the striatum and anterior cingulate cortex (ACC in HD mice, nor the overall decrease in brain weight, measured at 9 months of age. At this age, the density of ubiquitinated protein aggregates in the striatum and ACC is also not significantly ameliorated by environmental enrichment or wheel running. Conclusion These results indicate that enhanced voluntary physical activity, commenced at an early presymptomatic stage, contributes to the positive effects of environmental enrichment. However, sensory and cognitive stimulation, as well as motor stimulation not associated with running, may constitute major components of the therapeutic benefits associated with enrichment

  7. The effects of the recent minimum temperature and water deficit increases on Pinus pinaster wood radial growth and density in southern Portugal.

    Directory of Open Access Journals (Sweden)

    Cathy Béatrice Kurz Besson

    2016-08-01

    Full Text Available Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events.To address this question, tree-ring width and density chronologies were built for a P. pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011.We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster’s vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster’s production capacity and quality in response to more arid conditions in the near future in the region.

  8. The Diurnal Cycle of Particle Sizes, Compositions, and Densities observed in Sacramento, CA during CARES Field Campaign

    Science.gov (United States)

    Beránek, J.; Vaden, T.; Imre, D. G.; Zelenyuk, A.

    2010-12-01

    A central objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) was to characterize unequivocally all aspects related to organics in aerosols. To this end, a range of instruments measured loadings, size distributions, compositions, densities, CCN activities, and optical properties of aerosol sampled in Sacramento, CA over the month of June 2010. We present the results of measurements conducted by our single particle mass spectrometer, SPLAT. SPLAT was used to measure the size, composition, and density of individual particles with diameters between 50 to 2000 nm. SPLAT measured the vacuum aerodynamic diameters (dva) of more than 2 million particles and the compositions of ~350,000 particles, each day. In addition, SPLAT was used in combination with a differential mobility analyzer to measure the density, or effective density of individual particles. These measurements were typically conducted twice per day: in the morning, and mid-afternoon. Preliminary analysis of the data shows that under most conditions, the particles were relatively small (below 200 nm), and the vast majority of them were composed of oxygenated organics mixed with various amounts of sulfates. Analysis of the mass spectra shows that the oxygenated organics in these particles are the oxidized products of biogenic volatile organic precursors. In addition to particles composed of SOA mixed with sulfates, we detected and characterized fresh and processed soot particles, biomass burning aerosol, organic amines, sea salt - fresh and processed - and a small number of dust and other inorganic particles, commonly found in urban environment. SOA mixed with sulfates were the vast majority of particles at all times, while the other particle types exhibited episodic behavior. The data shows a reproducible diurnal pattern in SOA size distributions, number concentrations, and compositions. Early in the morning the particle number concentrations are relatively low, and the particle size

  9. Fear extinction deficits following acute stress associate with increased spine density and dendritic retraction in basolateral amygdala neurons

    OpenAIRE

    Maroun, Mouna; Ioannides, Pericles J.; Bergman, Krista L.; Kavushansky, Alexandra; Holmes, Andrew; Wellman, Cara L.

    2013-01-01

    Stress-sensitive psychopathologies such as post-traumatic stress disorder are characterized by deficits in fear extinction and dysfunction of corticolimbic circuits mediating extinction. Chronic stress facilitates fear conditioning, impairs extinction, and produces dendritic proliferation in the basolateral amygdala (BLA), a critical site of plasticity for extinction. Acute stress impairs extinction, alters plasticity in the medial prefrontal cortex-to-BLA circuit, and causes dendritic retrac...

  10. Quantitative Raman Measurement of the Evolution of the Cooper-pair Density with Doping in Bi2Sr2CaCu2O8+δ Superconductors

    International Nuclear Information System (INIS)

    Blanc, S.; Gu, G.; Gallais, Y.; Sacuto, A.; Cazayous, M.; Measson, M.A.; Wen, J.S.; Xu, Z.J.

    2009-01-01

    We report Raman measurements on Bi 2 Sr 2 CaCu 2 O 8+δ single crystals that allow us to quantitatively evaluate the doping dependence of the density of Cooper pairs in the superconducting state. We show that the drastic loss of Cooper pairs in the antinodal region as the doping level is reduced is concomitant with a deep alteration of the quasiparticles dynamic above T c and consistent with a pseudogap that competes with superconductivity. Our data also reveal that the overall density of Cooper pairs evolves with doping, distinctly from the superfluid density above the doping level p c = 0.2.

  11. Electrical transport characteristics of Bi2Sr2CaCu2O8+δstacked junctions with control of the carrier density

    International Nuclear Information System (INIS)

    Inomata, Kunihiro; Kawae, Takeshi; Kim, Sang-Jae; Nakajima, Kensuke; Yamashita, Tsutomu; Sato, Shigeo; Nakajima, Koji; Hatano, Takeshi

    2003-01-01

    The control of the critical current density (J c ) and the junction resistance (R N ) along the c-axis of intrinsic Josephson junctions (IJJs) on a high-T c superconductor is very important for applying the IJJs to electronic devices. For controlling these junction parameters, we have clarified the relationship of J c , R N and the carrier density in Bi 2 Sr 2 CaCu 2 O 8+δ whiskers by changing the carrier density with an annealing process. We determined the electrical transport characteristics of the IJJs. As a result, the J c increased, and the R N decreased systematically when the carrier density increased. The values of J c and R N could be controlled by a change in the carrier density

  12. Brevican-deficient mice display impaired hippocampal CA1 long-term potentiation but show no obvious deficits in learning and memory

    DEFF Research Database (Denmark)

    Brakebusch, Cord; Seidenbecher, Constanze I; Asztely, Fredrik

    2002-01-01

    to be less prominent in mutant than in wild-type mice. Brevican-deficient mice showed significant deficits in the maintenance of hippocampal long-term potentiation (LTP). However, no obvious impairment of excitatory and inhibitory synaptic transmission was found, suggesting a complex cause for the LTP defect....... Detailed behavioral analysis revealed no statistically significant deficits in learning and memory. These data indicate that brevican is not crucial for brain development but has restricted structural and functional roles....

  13. Enhanced Energy-Storage Density and High Efficiency of Lead-Free CaTiO3-BiScO3 Linear Dielectric Ceramics.

    Science.gov (United States)

    Luo, Bingcheng; Wang, Xiaohui; Tian, Enke; Song, Hongzhou; Wang, Hongxian; Li, Longtu

    2017-06-14

    A novel lead-free (1 - x)CaTiO 3 -xBiScO 3 linear dielectric ceramic with enhanced energy-storage density was fabricated. With the composition of BiScO 3 increasing, the dielectric constant of (1 - x)CaTiO 3 -xBiScO 3 ceramics first increased and then decreased after the composition x > 0.1, while the dielectric loss decreased first and increased. For the composition x = 0.1, the polarization was increased into 12.36 μC/cm 2 , 4.6 times higher than that of the pure CaTiO 3 . The energy density of 0.9CaTiO 3 -0.1BiScO 3 ceramic was 1.55 J/cm 3 with the energy-storage efficiency of 90.4% at the breakdown strength of 270 kV/cm, and the power density was 1.79 MW/cm 3 . Comparison with other lead-free dielectric ceramics confirmed the superior potential of CaTiO 3 -BiScO 3 ceramics for the design of ceramics capacitors for energy-storage applications. First-principles calculations revealed that Sc subsitution of Ti-site induced the atomic displacement of Ti ions in the whole crystal lattice, and lattice expansion was caused by variation of the bond angles and lenghths. Strong hybridization between O 2p and Ti 3d was observed in both valence band and conduction band; the hybridization between O 2p and Sc 3d at high conduction band was found to enlarge the band gap, and the static dielectric tensors were increased, which was the essential for the enhancement of polarization and dielectric properties.

  14. Bone-mineral density deficits from childhood cancer and its therapy. A review of at-risk patient cohorts and available imaging methods

    International Nuclear Information System (INIS)

    Kaste, Sue C.

    2004-01-01

    The growing population of childhood cancer survivors - currently estimated at 1 in 900 young adults aged 15-45 years - underscores the importance of studying long-term complications of oncotherapy. While these patients are returning to the mainstream of life, they carry with them toxicities from prior therapy that may compound or potentiate changes typically seen with the normal aging process. Skeletal toxicities such as scoliosis, craniofacial dysplasia, and limb-length discrepancy are readily apparent. However, others such as osteoporosis and osteonecrosis are silent until they reach advanced stages when attempts at amelioration may be unsuccessful. This review addresses bone-mineral density deficits that may predispose childhood cancer survivors to earlier onset and more severe osteopenia and osteoporosis than the normal population. (orig.)

  15. Critical current density, irreversibility line, and flux creep activation energy in silver-sheathed Bi2Sr2Ca2Cu3Ox superconducting tapes

    International Nuclear Information System (INIS)

    Shi, D.; Wang, Z.; Sengupta, S.; Smith, M.; Goodrich, L.F.; Dou, S.X.; Liu, H.K.; Guo, Y.C.

    1992-08-01

    Transport data, magnetic hysteresis and flux creep activation energy experimental results are presented for silver-sheathed high-T c Bi 2 Sr 2 Ca 2 Cu 3 O x superconducting tapes. The 110 K superconducting phase was formed by lead doping in a Bi-Sr-Ca-Cu-0 system. The transport critical current density was measured at 4.0 K to be 0.7 x 10 5 A/cm 2 (the corresponding critical current is 74 A) at zero field and 1.6 x 10 4 A/cm 2 at 12 T for H parallel ab. Excellent grain alignment in the a-b plane was achieved by a short-melting method, which considerably improved the critical current density and irreversibility line. Flux creep activation energy as a function of current is obtained based on the magnetic relaxation measurements

  16. Critical current density of four-CuO2-layer T1Ba2Ca3Cu4O11-δ

    International Nuclear Information System (INIS)

    Zhang, L.; Liu, J.Z.; Shelton, R.N.

    1998-01-01

    Full text: A key requirement for technological application is to have superconductors with high critical current density at practical operating temperatures and magnetic fields. The critical current density is strongly related to underlying properties of high T c superconductors, such as layering, anisotropy and other intrinsic material structures. The thallium-based superconductors attracted much attention at early stage mainly due to their high superconducting transitions. Recent studies show that these materials appear to be a better choice for achieving higher critical current density because of a stronger interlayer coupling between superconducting layers. Single crystals of TlBa 2 Ca 3 Cu 4 O 11-δ were grown by a self-flux method. This material is a strong-layered superconductor with four-CuO 2 -planes in a unit cell and a superconducting transition temperature of 128K. Our experimental results show that TlBa 2 Ca 3 Cu 4 O 11-δ crystals have high irreversibility line, large critical current density and high upper critical field. The impact of layering and the number of Cu-O layers on flux pinning, critical current density and other magnetic properties will also be discussed

  17. Plasma hormonal profiles and dendritic spine density and morphology in the hippocampal CA1 stratum radiatum, evidenced by light microscopy, of virgin and postpartum female rats.

    Science.gov (United States)

    Brusco, Janaína; Wittmann, Raul; de Azevedo, Márcia S; Lucion, Aldo B; Franci, Celso R; Giovenardi, Márcia; Rasia-Filho, Alberto A

    2008-06-27

    Successful reproduction requires that changes in plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oxytocin (OT), estrogen (E(2)) and progesterone (P(4)) occur together with the display of maternal behaviors. Ovarian steroids and environmental stimuli can affect the dendritic spines in the rat hippocampus. Here, studying Wistar rats, it is described: (a) the sequential and concomitant changes in the hormonal profile of females at postpartum days (PP) 4, 8, 12, 16, 20 and 24, comparing to estrous cycle referential values; (b) the dendritic spine density in the stratum radiatum of CA1 (CA1-SR) Golgi-impregnated neurons in virgin females across the estrous cycle and in multiparous age-matched ones; and (c) the proportion of different types of spines in the CA1-SR of virgin and postpartum females, both in diestrus. Plasma levels of gonadotrophins and ovarian hormones remained low along PP while LH increased and PRL decreased near the end of the lactating period. The lowest dendritic spine density was found in virgin females in estrus when compared to diestrus and proestrus phases or to postpartum females in diestrus (p0.4). There were no differences in the proportions of the different spine types in nulliparous and postpartum females (p>0.2). Results suggest that medium layer CA1-SR spines undergo rapid modifications in Wistar females across the estrous cycle (not quite comparable to Sprague-Dawley data or to hormonal substitutive therapy following ovariectomy), but persistent effects of motherhood on dendritic spine density and morphology were not found in this area.

  18. Dopamine transporter density in the basal ganglia assessed with 123I-IPT SPECT in children with attention deficit hyperactivity disorder

    International Nuclear Information System (INIS)

    Yoo, Y. H.; Cheon, K. A.; Yoon, M. J.; Kim, C. H.; Lee, J. D.; Kim, H. H.; Choi, T. H.

    2002-01-01

    Attention deficit hyperactivity disorder (ADHD) is known as a psychiatric disorder in childhood associated with dopamine dysregulation. We investigated dopamine transporter (DAT) density in children with ADHD in the present study using 123 I-IPT SPECT and postulated that an alteration in DAT density in the basal ganglia (BG) is responsible for dopaminergic dysfunction in children with ADHD. 9 durg-naive children with ADHD and 6 normal children were included in the study. We performed brain SPECT 2 hours after administration of 123 I-IPT and made both quantitative and qualitative analyses for assessment of specific/nonspecific DAT binding ratio in the BG. We investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale and specific/nonspecific DAT binding ratio in the BG. Drug-naive children with ADHD showed a significantly incresed specific/nonspecific DAT binding ratio in the BG compared with normal children. Whereas, no significant correlation was found between severity scores of symptoms in children with ADHD and specific/nonspecific DAT binding ratio n the BG. Our findings support complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD

  19. Dopamine transporter density in the basal ganglia assessed with [123I]IPT SPET in children with attention deficit hyperactivity disorder

    International Nuclear Information System (INIS)

    Cheon, Keun-Ah; Kim, Young-Kee; Namkoong, Kee; Kim, Chan-Hyung; Ryu, Young Hoon; Lee, Jong Doo

    2003-01-01

    Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder in childhood that is known to be associated with dopamine dysregulation. In this study, we investigated dopamine transporter (DAT) density in children with ADHD using iodine-123 labelled N-(3-iodopropen-2-yl)-2β-carbomethoxy-3β-(4-chlorophenyl) tropane ([ 123 I]IPT) single-photon emission tomography (SPET) and postulated that an alteration in DAT density in the basal ganglia is responsible for dopaminergic dysfunction in children with ADHD. Nine drug-naive children with ADHD and six normal children were included in the study. We performed brain SPET 2 h after the intravenous administration of [ 123 I]IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale-IV and the specific/non-specific DAT binding ratio in the basal ganglia. Drug-naive children with ADHD showed a significantly increased specific/non-specific DAT binding ratio in the basal ganglia compared with normal children. However, no significant correlation was found between the severity scores of ADHD symptoms in children with ADHD and the specific/non-specific DAT binding ratio in the basal ganglia. Our findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD. (orig.)

  20. Dopamine transporter density in the basal ganglia assessed with {sup 123}I-IPT SPECT in children with attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Y. H.; Cheon, K. A.; Yoon, M. J.; Kim, C. H.; Lee, J. D. [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, H. H.; Choi, T. H. [Gachon Medical School, Incheon (Korea, Republic of)

    2002-07-01

    Attention deficit hyperactivity disorder (ADHD) is known as a psychiatric disorder in childhood associated with dopamine dysregulation. We investigated dopamine transporter (DAT) density in children with ADHD in the present study using {sup 123}I-IPT SPECT and postulated that an alteration in DAT density in the basal ganglia (BG) is responsible for dopaminergic dysfunction in children with ADHD. 9 durg-naive children with ADHD and 6 normal children were included in the study. We performed brain SPECT 2 hours after administration of {sup 123}I-IPT and made both quantitative and qualitative analyses for assessment of specific/nonspecific DAT binding ratio in the BG. We investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale and specific/nonspecific DAT binding ratio in the BG. Drug-naive children with ADHD showed a significantly incresed specific/nonspecific DAT binding ratio in the BG compared with normal children. Whereas, no significant correlation was found between severity scores of symptoms in children with ADHD and specific/nonspecific DAT binding ratio n the BG. Our findings support complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD.

  1. Dopamine transporter density in the basal ganglia assessed with [{sup 123}I]IPT SPET in children with attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Cheon, Keun-Ah; Kim, Young-Kee; Namkoong, Kee; Kim, Chan-Hyung [Department of Psychiatry, College of Medicine, Yonsei University, Seoul (Korea); Ryu, Young Hoon; Lee, Jong Doo [Division of Nuclear Medicine, Department of Radiology, College of Medicine, Yonsei University, 146-92 Dogokdong, Gangnam-Gu, Seoul, 135-720 (Korea)

    2003-02-01

    Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder in childhood that is known to be associated with dopamine dysregulation. In this study, we investigated dopamine transporter (DAT) density in children with ADHD using iodine-123 labelled N-(3-iodopropen-2-yl)-2β-carbomethoxy-3β-(4-chlorophenyl) tropane ([{sup 123}I]IPT) single-photon emission tomography (SPET) and postulated that an alteration in DAT density in the basal ganglia is responsible for dopaminergic dysfunction in children with ADHD. Nine drug-naive children with ADHD and six normal children were included in the study. We performed brain SPET 2 h after the intravenous administration of [{sup 123}I]IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale-IV and the specific/non-specific DAT binding ratio in the basal ganglia. Drug-naive children with ADHD showed a significantly increased specific/non-specific DAT binding ratio in the basal ganglia compared with normal children. However, no significant correlation was found between the severity scores of ADHD symptoms in children with ADHD and the specific/non-specific DAT binding ratio in the basal ganglia. Our findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD. (orig.)

  2. Sperm Na+, K+-ATPase and Ca2+-ATPase activity: A preliminary study of comparison of swim up and density gradient centrifugation methods for sperm preparation

    Science.gov (United States)

    Lestari, Silvia W.; Larasati, Manggiasih D.; Asmarinah, Mansur, Indra G.

    2018-02-01

    As one of the treatment for infertility, the success rate of Intrauterine Insemination (IUI) is still relatively low. Several sperm preparation methods, swim-up (SU) and the density-gradient centrifugation (DGC) are frequently used to select for better sperm quality which also contribute to IUI failure. Sperm selection methods mainly separate the motile from the immotile sperm, eliminating the seminal plasma. The sperm motility involves the structure and function of sperm membrane in maintaining the balance of ion transport system which is regulated by the Na+, K+-ATPase, and Ca2+-ATPase enzymes. This study aims to re-evaluate the efficiency of these methods in selecting for sperm before being used for IUI and based the evaluation on sperm Na+,K+-ATPase and Ca2+-ATPase activities. Fourteen infertile men from couples who underwent IUI were involved in this study. The SU and DGC methods were used for the sperm preparation. Semen analysis was performed based on the reference value of World Health Organization (WHO) 2010. After isolating the membrane fraction of sperms, the Na+, K+-ATPase activity was defined as the difference in the released inorganic phosphate (Pi) with and without the existence of 10 mM ouabain in the reaction, while the Ca2+-ATPase was determined as the difference in Pi contents with and without the existence of 55 µm CaCl2. The prepared sperm demonstrated a higher percentage of motile sperm compared to sperm from the whole semen. Additionally, the percentage of motile sperm of post-DGC showed higher result than the sperm from post-SU. The velocity of sperm showed similar pattern with the percentage of motile sperm, in which the velocity of prepared sperm was higher than the sperm from whole semen. Furthermore, the sperm velocity of post-DGC was higher compared to the sperm from post-SU. The Na+, K+-ATPase activity of prepared sperm was higher compared to whole semen, whereas Na+, K+-ATPase activity in the post DGC was higher than post SU. The Ca2

  3. Structural, electronic, optical and thermoelectric investigations of antiperovskites A3SnO (A = Ca, Sr, Ba) using density functional theory

    Science.gov (United States)

    Hassan, M.; Shahid, A.; Mahmood, Q.

    2018-02-01

    Density functional theory study of the structural, electrical, optical and thermoelectric behaviors of very less investigated anti-perovskites A3SnO (A = Ca, Sr, Ba) is performed with FP-LAPW technique. The A3SnO exhibit narrow direct band gap, in contrast to the wide indirect band gap of the respective perovskites. Hence, indirect to direct band gap transformation can be realized by the structural transition from perovskite to anti-perovskite. The p-p hybridization between A and O states result in the covalent bonding. The transparency and maximum reflectivity to the certain energies, and the verification of the Penn's model indicate potential optical device applications. Thermoelectric behaviors computed within 200-800 K depict that Ca3SnO exhibits good thermoelectric performance than Ba3SnO and Sr3SnO, and all three operate at their best at 800 K suggesting high temperature thermoelectric device applications.

  4. High-density Bi-Pb-Sr-Ca-Cu-O superconductor prepared by rapid thermal melt processing

    Science.gov (United States)

    Moon, B. M.; Lalevic, B.; Kear, B. H.; McCandlish, L. E.; Safari, A.; Meskoob, M.

    1989-10-01

    A high quality, dense Bi-Pb-Sr-Ca-Cu-O superconductor has been successfully synthesized by rapid thermal melt processing. Conventionally sintered pellets were melted at 1200 °C, cooled rapidly, and then annealed. As-melted samples exhibited semiconductor behavior, which upon annealing became superconducting at 115 K [Tc(zero)=105 K]. A detailed study of various processing techniques has been carried out.

  5. Study of critical current density from ac susceptibility measurements in (La1-xYx)2Ba2CaCu5O2 superconductors

    International Nuclear Information System (INIS)

    Nayak, P.K.; Ravi, S. . sravi@iitg.ernet.in

    2008-01-01

    We have prepared a series of compounds (La 1-x Y x ) 2 Ba 2 CaCu 5 O 2 for x = 0 to 0.5 by adding a CaCuO 2 layer to the parent compound La 2 Ba 2 Cu 4 O 2 and by doping Y in place of La. These materials are also prepared by adding 5 wt% of Ag to enhance the intergranular coupling and critical current density. X-ray diffraction measurements show that all the samples are essentially in single phase form and the patterns could be refined using P4/mmm space group in tetragonal cell. The typical lattice parameters are found to be a = b 3.856 A, c = 11.576 A for x = 0.5 sample. Temperature variations of dc electrical resistivity measured on the above samples show that they exhibit superconductivity with T c ranging from 60 to 75 K. Temperature and ac field amplitude variation of ac susceptibility have been measured on the above samples. The field variation of ac susceptibility data has been analyzed by using Bean critical state model. Using both temperature and field variations of ac susceptibility data, the material dependent parameters, such as critical current density as a function of temperature and effective volume fraction grains have been estimated. The Ag doped samples show relatively large critical current density compared to pure samples due to improved intergranular coupling. (author)

  6. CaMKII inhibition with KN93 attenuates endothelin and serotonin receptor-mediated vasoconstriction and prevents subarachnoid hemorrhage-induced deficits in sensorimotor function

    DEFF Research Database (Denmark)

    Edvinsson, Lars; Povlsen, Gro Klitgaard; Ahnstedt, Hilda

    2014-01-01

    tested the hypothesis that inhibition of calcium calmodulin-dependent protein kinase II (CaMKII) may reduce cerebral vasoconstriction mediated by endothelin and serotonin receptors and improve neurological outcome after experimental SAH. METHODS: SAH was induced in adult rats by injection of 250 μ...

  7. Measurement of the mass attenuation coefficients and electron densities for BiPbSrCaCuO superconductor at different energies

    Science.gov (United States)

    Çevik, U.; Baltaş, H.

    2007-03-01

    The mass attenuation coefficients for Bi, Pb, Sr, Ca, Cu metals, Bi2O3, PbO, SrCO3, CaO, CuO compounds and solid-state forms of Bi1.7Pb0.3Sr2Ca2Cu3O10 superconductor were determined at 57.5, 65.2, 77.1, 87.3, 94.6, 122 and 136 keV energies. The samples were irradiated using a 57Co point source emitted 122 and 136 keV γ-ray energies. The X-ray energies were obtained using secondary targets such as Ta, Bi2O3 and (CH3COO)2UO22H2O. The γ- and X-rays were counted by a Si(Li) detector with a resolution of 0.16 keV at 5.9 keV. The effect of absorption edges on electron density, effective atomic numbers and their variation with photon energy in composite superconductor samples was discussed. Obtained values were compared with theoretical values.

  8. Effects of fiber density and plasma modification of nanofibrous membranes on the adhesion and growth of HaCaT keratinocytes.

    Science.gov (United States)

    Bacakova, Marketa; Lopot, Frantisek; Hadraba, Daniel; Varga, Marian; Zaloudkova, Margit; Stranska, Denisa; Suchy, Tomas; Bacakova, Lucie

    2015-01-01

    It may be possible to regulate the cell colonization of biodegradable polymer nanofibrous membranes by plasma treatment and by the density of the fibers. To test this hypothesis, nanofibrous membranes of different fiber densities were treated by oxygen plasma with a range of plasma power and exposure times. Scanning electron microscopy and mechanical tests showed significant modification of nanofibers after plasma treatment. The intensity of the fiber modification increased with plasma power and exposure time. The exposure time seemed to have a stronger effect on modifying the fiber. The mechanical behavior of the membranes was influenced by the plasma treatment, the fiber density, and their dry or wet state. Plasma treatment increased the membrane stiffness; however, the membranes became more brittle. Wet membranes displayed significantly lower stiffness than dry membranes. X-ray photoelectron spectroscopy (XPS) analysis showed a slight increase in oxygen-containing groups on the membrane surface after plasma treatment. Plasma treatment enhanced the adhesion and growth of HaCaT keratinocytes on nanofibrous membranes. The cells adhered and grew preferentially on membranes of lower fiber densities, probably due to the larger area of void spaces between the fibers. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  9. On exposure to anorexia nervosa, the temporal variation in axial and appendicular skeletal development predisposes to site-specific deficits in bone size and density: a cross-sectional study.

    Science.gov (United States)

    Seeman, E; Karlsson, M K; Duan, Y

    2000-11-01

    Skeletal development is heterogeneous. Throughout growth, bone size is more maturationally advanced than the mineral being accrued within its periosteal envelope; before puberty, appendicular growth is more rapid than axial growth; during puberty, appendicular growth slows and axial growth accelerates. We studied women with differing age of onset of anorexia nervosa to determine whether this temporal heterogeneity in growth predisposed to the development of deficits in bone size and volumetric bone mineral density (vBMD), which varied by site and severity depending on the age at which anorexia nervosa occurred. Bone size and vBMD of the third lumbar vertebra and femoral neck were measured using dual-energy X-ray absorptiometry in 210 women aged 21 years (range, 12-40 years) with anorexia nervosa. Results were expressed as age-specific SDs (mean +/- SEM). Bone width depended on the age of onset of anorexia nervosa; when the onset of anorexia nervosa occurred (1) before 15 years of age, deficits in vertebral body and femoral neck width did not differ (-0.77+/-0.27 SD and -0.55+/-0.17 SD, respectively); (2) between 15 and 19 years of age, deficits in vertebral body width (-0.95+/-0.16 SD) were three times the deficits in femoral neck width (-0.28+/-0.14 SD; p anorexia nervosa. No deficit in bone width was observed at the femoral neck. Deficits in vBMD at the vertebra and femoral neck were independent of the age of onset of anorexia nervosa but increased as the duration of anorexia nervosa increased, being about 0.5 SD lower at the vertebra than femoral neck. We infer that the maturational development of a region at the time of exposure to disease, and disease duration, determine the site, magnitude, and type of trait deficit in anorexia nervosa. Bone fragility due to reduced bone size and reduced vBMD in adulthood is partly established during growth.

  10. Improvement of critical current density in thallium-based (Tl, Bi)Sr1.6Ba0.4Ca2Cu3O9-δ superconductors

    International Nuclear Information System (INIS)

    Ren, Z.F.; Wang, C.A.; Wang, J.H.

    1994-07-01

    Epitaxial (Tl,Bi)Sr 1.6 Ba 0.4 Ca 2 Cu 3 O x ((Tl, Bi)-1223) thin films on (100) single crystal LaAlO 3 substrates were synthesized by a two-step procedure. Phase development, microstructure, and relationships between film and substrate were studied by x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Resistance versus temperature, zero-field-cooled and field-cooled magnetization, and transport critical current density (J c ) were measured. The zero-resistance temperature was 105--111 K. J c at 77 K and zero field was >2 x 10 6 A/cm 2 . The films exhibited good flux pinning properties

  11. Improvement of critical current density in thallium-based (Tl,Bi)Sr1.6Ba0.4Ca2Cu3Ox superconductors

    International Nuclear Information System (INIS)

    Ren, Z.F.; Wang, C.A.; Wang, J.H.

    1994-01-01

    Epitaxial (Tl,Bi)Sr 1.6 Ba 0.4 Ca 2 Cu 3 O x (Tl,Bi)-1223 thin films on (100) single crystal LaAlO 3 substrates were synthesized by a two-step procedure. Phase development, microstructure, and relationships between film and substrate were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Resistance versus temperature, zero-field-cooled and field-cooled magnetization, and transport critical current density (J c ) were measured. The zero-resistance temperature was 105-111 K. J c at 77 K and zero field was > 2 x 10 6 A/cm 2 . The films exhibited good flux pinning properties

  12. Critical current density and flux pinning in superconducting wires and coils of silver-clad Bi-Pb-Sr-Ca-Cu-O

    International Nuclear Information System (INIS)

    Dou, S.X.; Liu, H.K.; Apperley, M.H.; Song, K.H.; Sorrell, C.C.; Guo, S.J.; Loberg, B.; Easterling, K.E.

    1991-01-01

    The critical current density (J c ) of Ag-clad of Bi-Pb-Sr-Ca-Cu-O has been measured to be about 12,000 A/cm 2 at 77 K in zero field. This wire was rolled into a tape of thickness 0.1 mm and width of 2 to 3 mm, and a coil of 35 mm diameter was formed. The J c of this coil was measured to be about 2,000 A/cm 2 at 77 K over the full length (1.00 meter) of the coil. In this paper compositions, heat treatment parameters, and cold-deformation for enhancement of J c are presented. The microstructure is characterized and pinning interactions as well as possible weak links are emphasised. (orig.)

  13. Filament to filament bridging and its influence on developing high critical current density in multifilamentary Bi2Sr2CaCu2Ox round wires

    International Nuclear Information System (INIS)

    Shen, T; Jiang, J; Kametani, F; Trociewitz, U P; Larbalestier, D C; Schwartz, J; Hellstrom, E E

    2010-01-01

    Increasing the critical current density (J c ) of the multifilamentary round wire Ag/Bi 2 Sr 2 CaCu 2 O x (2212) requires understanding its complicated microstructure, in which extensive bridges between filaments are prominent. In this first through-process quench study of 2212 round wire, we determined how its microstructure develops during a standard partial-melt process and how filament bridging occurs. We found that filaments can bond together in the melt state. As 2212 starts to grow on subsequent cooling, we observed that two types of 2212 bridges form. One type, which we call Type-A bridges, forms within filaments that bonded in the melt; Type-A bridges are single grains that span multiple bonded filaments. The other type, called Type-B bridges, form between discrete filaments through 2212 outgrowths that penetrate into the Ag matrix and intersect with other 2212 outgrowths from adjacent filaments. We believe the ability of these two types of bridges to carry inter-filament current is intrinsically different: Type-A bridges are high- J c inter-filament paths whereas Type-B bridges contain high-angle grain boundaries and are typically weak linked. Slow cooling leads to more filament bonding, more Type-A bridges and a doubling of J c without changing the flux pinning. We suggest that Type-A bridges create a 3D current flow that is vital to developing high J c in multifilamentary 2212 round wire.

  14. Increasing Hydrogen Density with the Cation-Anion Pair BH4−-NH4+ in Perovskite-Type NH4Ca(BH43

    Directory of Open Access Journals (Sweden)

    Pascal Schouwink

    2015-08-01

    Full Text Available A novel metal borohydride ammonia-borane complex Ca(BH42·NH3BH3 is characterized as the decomposition product of the recently reported perovskite-type metal borohydride NH4Ca(BH43, suggesting that ammonium-based metal borohydrides release hydrogen gas via ammonia-borane-complexes. For the first time the concept of proton-hydride interactions to promote hydrogen release is applied to a cation-anion pair in a complex metal hydride. NH4Ca(BH43 is prepared mechanochemically from Ca(BH42 and NH4Cl as well as NH4BH4 following two different protocols, where the synthesis procedures are modified in the latter to solvent-based ball-milling using diethyl ether to maximize the phase yield in chlorine-free samples. During decomposition of NH4Ca(BH43 pure H2 is released, prior to the decomposition of the complex to its constituents. As opposed to a previously reported adduct between Ca(BH42 and NH3BH3, the present complex is described as NH3BH3-stuffed α-Ca(BH42.

  15. Fragmentation of the gastrodermis and detachment of zooxanthellae in symbiotic cnidarians: a role for hydrogen peroxide and Ca2+ in coral bleaching and algal density control

    OpenAIRE

    I. M Sandeman

    2006-01-01

    Coral bleaching involves the detachment of zooxanthellae and the simultaneous fragmentation of the gastrodermis. Results obtained with a cell permeant fluorescent probe for calcium ions (Ca2+) indicates that "thermal" bleaching is the result of a temperature related breakdown of the Ca2+ exclusion system. "Solar" bleaching, which takes place at lower temperatures and is driven by light, is the result of a build-up of photo-synthetically produced hydrogen peroxide in the tissues. Gastrodermal ...

  16. A common behaviour of thermoelectric layered cobaltites: incommensurate spin density wave states in [Ca2Co4/3Cu2/3O4]0.62[CoO2] and [Ca2CoO3]0.62[CoO2

    International Nuclear Information System (INIS)

    Sugiyama, J; Brewer, J H; Ansaldo, E J; Itahara, H; Dohmae, K; Xia, C; Seno, Y; Hitti, B; Tani, T

    2003-01-01

    Magnetism of a misfit layered cobaltite [Ca 2 Co 4/3 Cu 2/3 O 4 ] x RS [CoO 2 ] (x ∼ 0.62, RS denotes a rocksalt-type block) was investigated by a positive muon spin rotation and relaxation (μ + SR) experiment. A transition to an incommensurate (IC) spin density wave (SDW) state was found below 180 K (= T C on ); and a clear oscillation due to a static internal magnetic field was observed below 140 K(= T C ). Furthermore, an anisotropic behaviour of the zero-field μ + SR experiment indicated that the IC-SDW lies in the a-b plane, with oscillating moments directed along the c axis. These results were quite similar to those for the related compound [Ca 2 CoO 3 ] 0.62 RS [CoO 2 ], i.e., Ca 3 Co 4 O 9 . Since the IC-SDW field in [Ca 2 Co 4/3 Cu 2/3 O 4 ] 0.62 RS [CoO 2 ] was approximately the same as those in pure and doped [Ca 2 CoO 3 ] 0.62 RS [CoO 2 ], it was concluded that the IC-SDW exists in the [CoO 2 ] planes

  17. Different Densities of Na-Ca Exchange Current in T-Tubular and Surface Membranes and Their Impact on Cellular Activity in a Model of Rat Ventricular Cardiomyocyte

    Czech Academy of Sciences Publication Activity Database

    Pásek, Michal; Šimurda, J.; Christé, G.

    2017-01-01

    Roč. 2017, č. 2017 (2017), č. článku 6343821. ISSN 2314-6133 Institutional support: RVO:61388998 Keywords : rat ventricular cell * mathematical model * Na-Ca current * t-tubules Subject RIV: BO - Biophysics OBOR OECD: Biophysics Impact factor: 2.476, year: 2016

  18. Limnological characteristics and seasonal changes in density and diversity of the phytoplanktonic community at the Caçó pond, Maranhão State, Brazil

    Directory of Open Access Journals (Sweden)

    Maria José Dellamano-Oliveira

    2003-12-01

    Full Text Available Seasonal changes of the phytoplanktonic community and limnological abiotic characteristics of Caçó pond (Maranhão State, Brazil was evaluated from two field researches during the rainy (April 1999 and dry (November 1999 seasons. Measurements of twelve chemical and physical variables and phytoplankton collections were carried out at eight sampling stations. The Chlorophyceae and Cyanobacteria groups were in highest fractions during the rainy and dry seasons, respectively. The limnological abiotic variables showed a homogenous spatial distribution. The cluster analysis, using Bray-Curtis distance, distinguished two major groups, represented by the most common and abundant species in both the periods. The results showed that the climate regime, due to the seasonal changes in pluviosity, was a determinant over the phytoplanktonic community structure at Caçó pond.Mudanças sazonais na comunidade fitoplanctônica e nas características limnológicas abióticas da lagoa do Caçó, Estado do Maranhão, Brasil, foram avaliadas a partir de duas coletas, nos períodos de chuva (Abril/1999 e seca (Novembro/1999. Medidas de quatorze variáveis físicas e químicas e coletas do fitoplâncton foram realizadas em oito estações de amostragem. Quantitativamente, os grupos Chlorophyceae e Cyanobacteria apresentaram maior contribuição nos períodos de chuva e seca, respectivamente. As variáveis limnológicas abióticas mostraram uma distribuição espacial homogênea em relação aos dois períodos amostrados. A análise de agrupamento a partir da distância de Bray-Curtis para comunidade fitoplanctônica distinguiu dois grandes grupos (estação seca e chuvosa, representados pelas espécies mais comuns e abundantes em ambos períodos. Os resultados deste estudo permitiram concluir que o regime climatológico foi determinante sobre a dinâmica e a estrutura da comunidade fitoplanctônica da lagoa do Caçó.

  19. Melts in the Deep Earth: Calculating the Densities of CaO-FeO-MgO-Al2O3-SiO2 Liquids

    Science.gov (United States)

    Thomas, C.; Guo, X.; Agee, C. B.; Asimow, P. D.; Lange, R. A.

    2012-12-01

    We present new equation of state (EOS) measurements for hedenbergite (Hd, CaFeSi2O6) and forsterite (Fo, Mg2SiO4) liquids. These liquid EOS add to the basis set in the CaO-FeO-MgO-Al2O3-SiO2 (CMASF) oxide space at elevated temperatures and pressures; other liquids include: enstatite (En, MgSiO3), anorthite (An, CaAl2Si2O8), diopside (Di, CaMgSi2O6), and fayalite (Fa, Fe2SiO4). The Hd EOS measurement was a multi-technique collaboration using 1-atm double-bob Archimedean, ultrasonic, sink/float, and shock wave techniques. Un-weighted linear fitting of the shock data in shock velocity (US)-particle velocity (up) space defines a pre-heated (1400 °C) Hugoniot US = 2.628(0.024) + 1.54(0.01)up km/s. The slope corresponds to a K' of 5.16(0.04), consistent with piston-cylinder and multi-anvil sink/float experiments. The intercept is fixed at the ultrasonic sound speed (Co) since the unconstrained intercept is within the stated error. This behavior demonstrates consistency across methods and that the liquid is relaxed during shock compression. Shock compression of pre-heated (2000°C) single crystal Fo gives an un-weighted linear Hugoniot of US = 2.674(0.188) + 1.64(0.06)up km/s. The unconstrained Co falls below estimates based on extrapolation in both temperature and composition from two published partial molar sound speed models, 3.195m/s [1] and 3.126 m/s [2]. The shock-derived Co indicates that dC/dT is negative for Fo liquid, contrary to the positive [1] and zero [2] temperature dependences derived over relatively narrow temperature intervals. CMASF liquid isentropes were calculated using five end-members (En, Fo, Fa, An, Di). For modeling crystallization of a fictive magma ocean, we examined two liquids: peridotite [3] (P=.33En+.56Fo+.07Fa+.03An+.007Di) and simplified chondrite [4] (Ch=.62En+.24Fo+.08Fa+.04An+.02Di). Each end-member is defined by a 3rd or 4th order Birch-Murnaghan isentrope, Mie-Grüneisen thermal pressure and a constant heat capacity. The volumes are

  20. The Density and Compressibility of BaCO3-SrCO3-CaCO3-K2CO3-Na2CO3-Li2CO3 Liquids: New Measurements and a Systematic Trend with Cation Field Strength

    Science.gov (United States)

    Hurt, S. M.; Lange, R. A.; Ai, Y.

    2015-12-01

    The volumetric properties of multi-component carbonate liquids are required to extend thermodynamic models that describe partial melting of the deep mantle (e.g. pMELTS; Ghiorso et al., 2003) to carbonate-bearing lithologies. Carbonate in the mantle is an important reservoir of carbon, which is released to the atmosphere as CO2 through volcanism, and thus contributes to the carbon cycle. Although MgCO3 is the most important carbonate component in the mantle, it is not possible to directly measure the 1-bar density and compressibility of MgCO3 liquid because, like other alkaline-earth carbonates, it decomposes at a temperature lower than its melting temperature. Despite this challenge, Liu and Lange (2003) and O'Leary et al. (2015) showed that the one bar molar volume, thermal expansion and compressibility of the CaCO3 liquid component could be obtained by measuring the density and sound speeds of stable liquids in the CaCO3-Li2CO3-Na2CO3-K2CO3 quaternary system at one bar. In this study, this same strategy is employed on SrCO3- and BaCO3-bearing alkali carbonate liquids. The density and sound speed of seven liquids in the SrCO3-Li2CO3-Na2CO3-K2CO3 quaternary and three liquids in the BaCO3-Li2CO3-Na2CO3-K2CO3 quaternary were measured from 739-1367K, with SrCO3 and BaCO3 concentrations ranging from 10-50 mol%. The density measurements were made using the double-bob Archimedean method and sound speeds were obtained with a frequency-sweep acoustic interferometer. The molar volume and sound speed measurements were used to calculate the isothermal compressibility of each liquid, and the results show the volumetric properties mix ideally with composition. The partial molar volume and compressibility of the SrCO3 and BaCO3 components are compared to those obtained for the CaCO3 component as a function of cation field strength. The results reveal a systematic trend that allows the partial molar volume and compressibility of the MgCO3 liquid component to be estimated.

  1. The gustin (CA6) gene polymorphism, rs2274333 (A/G), as a mechanistic link between PROP tasting and fungiform taste papilla density and maintenance.

    Science.gov (United States)

    Melis, Melania; Atzori, Elena; Cabras, Stefano; Zonza, Andrea; Calò, Carla; Muroni, Patrizia; Nieddu, Mariella; Padiglia, Alessandra; Sogos, Valeria; Tepper, Beverly J; Tomassini Barbarossa, Iole

    2013-01-01

    Taste sensitivity to PROP varies greatly among individuals and is associated with polymorphisms in the bitter receptor gene TAS2R38, and with differences in fungiform papilla density on the anterior tongue surface. Recently we showed that the PROP non-taster phenotype is strongly associated with the G variant of polymorphism rs2274333 (A/G) of the gene that controls the salivary trophic factor, gustin. The aims of this study were 1) to investigate the role of gustin gene polymorphism rs2274333 (A/G), in PROP sensitivity and fungiform papilla density and morphology, and 2) to investigate the effect of this gustin gene polymorphism on cell proliferation and metabolic activity. Sixty-four subjects were genotyped for both genes by PCR techniques, their PROP sensitivity was assessed by scaling and threshold methods, and their fungiform papilla density, diameter and morphology were determined. In vitro experiments examined cell proliferation and metabolic activity, following treatment with saliva of individuals with and without the gustin gene mutation, and with isolated protein, in the two iso-forms. Gustin and TAS2R38 genotypes were associated with PROP threshold (p=0.0001 and p=0.0042), but bitterness intensity was mostly determined by TAS2R38 genotypes (pTreatment of isolated cells with saliva from individuals with the AA form of gustin or direct application of the active iso-form of gustin protein increased cell proliferation and metabolic activity (p<0.0135). These novel findings suggest that the rs2274333 polymorphism of the gustin gene affects PROP sensitivity by acting on fungiform papilla development and maintenance, and could provide the first mechanistic explanation for why PROP super-tasters are more responsive to a broad range of oral stimuli.

  2. The gustin (CA6 gene polymorphism, rs2274333 (A/G, as a mechanistic link between PROP tasting and fungiform taste papilla density and maintenance.

    Directory of Open Access Journals (Sweden)

    Melania Melis

    Full Text Available Taste sensitivity to PROP varies greatly among individuals and is associated with polymorphisms in the bitter receptor gene TAS2R38, and with differences in fungiform papilla density on the anterior tongue surface. Recently we showed that the PROP non-taster phenotype is strongly associated with the G variant of polymorphism rs2274333 (A/G of the gene that controls the salivary trophic factor, gustin. The aims of this study were 1 to investigate the role of gustin gene polymorphism rs2274333 (A/G, in PROP sensitivity and fungiform papilla density and morphology, and 2 to investigate the effect of this gustin gene polymorphism on cell proliferation and metabolic activity. Sixty-four subjects were genotyped for both genes by PCR techniques, their PROP sensitivity was assessed by scaling and threshold methods, and their fungiform papilla density, diameter and morphology were determined. In vitro experiments examined cell proliferation and metabolic activity, following treatment with saliva of individuals with and without the gustin gene mutation, and with isolated protein, in the two iso-forms. Gustin and TAS2R38 genotypes were associated with PROP threshold (p=0.0001 and p=0.0042, but bitterness intensity was mostly determined by TAS2R38 genotypes (p<0.000001. Fungiform papillae densities were associated with both genotypes (p<0.014 (with a stronger effect for gustin; p=0.0006, but papilla morphology was a function of gustin alone (p<0.0012. Treatment of isolated cells with saliva from individuals with the AA form of gustin or direct application of the active iso-form of gustin protein increased cell proliferation and metabolic activity (p<0.0135. These novel findings suggest that the rs2274333 polymorphism of the gustin gene affects PROP sensitivity by acting on fungiform papilla development and maintenance, and could provide the first mechanistic explanation for why PROP super-tasters are more responsive to a broad range of oral stimuli.

  3. Fragmentation of the gastrodermis and detachment of zooxanthellae in symbiotic cnidarians: a role for hydrogen peroxide and Ca2+ in coral bleaching and algal density control

    Directory of Open Access Journals (Sweden)

    I. M Sandeman

    2006-12-01

    Full Text Available Coral bleaching involves the detachment of zooxanthellae and the simultaneous fragmentation of the gastrodermis. Results obtained with a cell permeant fluorescent probe for calcium ions (Ca2+ indicates that "thermal" bleaching is the result of a temperature related breakdown of the Ca2+ exclusion system. "Solar" bleaching, which takes place at lower temperatures and is driven by light, is the result of a build-up of photo-synthetically produced hydrogen peroxide in the tissues. Gastrodermal tissue with its symbionts, scraped from between septa of corals, was observed under controlled conditions of high light and temperature. Pieces of gastrodermis round off, zooxanthellae move to the surface, protrude from the surface and after a delay, detach, surrounded by a thin layer of host cytoplasm, inclusions and plasma membrane. The higher the temperature and light level the shorter the delay and higher the rate of algal detachment. Fragmentation by the ballooning-out and detachment of small spheres of cytoplasm (bleb formation takes place simultaneously. This is likely to be due to oxidation, by hydrogen peroxide (H2O2, of -SH groups on the cytoskeleton and its attachment to the plasma membrane. Ground, polished and stained thin acrylic resin sections reveal similar processes taking place in artificially bleached corals. Isolated zooxanthellae and whole corals are shown to release H2O2 in the light. This process of algal detachment and fragmentation that takes place at normal sea temperatures may underlie the mechanism limiting algal populations in the gastrodermis and may be localized to areas with a concentration of algae near the membrane. At above-normal temperatures under the synergistic effect of light and temperature, the rate of production of H2O2 exceeds the rate at which can it be lost by diffusion or destroyed and H2O2 accumulates. This results in damage to the calcium exclusion system, detachment of zooxanthellae into the coelenteron and

  4. Influence of the bismuth deficit on the structural and electric properties of the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} thin films synthesized by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Alami, H.El.; Rannou, I.; Deville Cavellin, C

    2004-07-15

    BiSrCaCuO thin films were grown on (1 0 0) SrTiO3 substrates by molecular beam epitaxy (MBE) with variation of the Bi deposition time. A new 2x212 family with x varied between 1 and 0 was grown. The X-ray study, the Rutherford back scattering (RBS), reflection high energy electron diffraction (RHEED) and atomic force microscopy (AFM) were used to characterize the films. It was shown that the growth method used leads to intergrowth nanostructures. The transport measurements of BiSrCaCuO thin films were performed. The results analysed using the theory of percolation show a 2D character of conductivity in the films studied.

  5. LaNiO3 buffer layers for high critical current density YBa2Cu3O7-δ and Tl2Ba2CaCu2O8-δ films

    International Nuclear Information System (INIS)

    Carlson, C.M.; Parilla, P.A.; Siegal, M.P.; Ginley, D.S.; Wang, Y.; Blaugher, R.D.; Price, J.C.; Overmyer, D.L.; Venturini, E.L.

    1999-01-01

    We demonstrate high critical current density superconducting films of YBa 2 Cu 3 O 7-δ (YBCO) and Tl 2 Ba 2 CaCu 2 O 8-δ (Tl-2212) using LaNiO 3 (LNO) buffer layers. YBCO films grown on an LNO buffer layer have only a slightly lower J c (5 K, H=0) than films grown directly on a bare LaAlO 3 substrate. YBCO films grown on LNO buffer layers exhibit minor microstructural disorder and enhanced flux pinning. LNO-buffered Tl-2212 samples show large reductions in J c at all temperatures and fields compared to those grown on bare LaAlO 3 , correlating to both a-axis grain and nonsuperconducting phase formation. LNO could be a promising buffer layer for both YBCO and Tl-based superconducting films in coated conductor applications. copyright 1999 American Institute of Physics

  6. LaNiO3 Buffer Layers for High Critical Current Density YBa2Cu3O7δ and Tl2Ba2CaCu2O8δ Films

    International Nuclear Information System (INIS)

    Carlson, C.M.; Parilla, P.A.; Siegal, M.P.; Ginley, D.S.; Wang, Y.-T.; Blaugher, R.D.; Price, J.C.; Overmyer, D.L.; Venturini, E.L.

    1999-01-01

    We demonstrate high critical current density superconducting films of YBa 2 Cu 3 O 7-δ (YBCO) and Tl 2 Ba 2 CaCu 2 O 8-δ (Tl-2212) using LaNiO 3 (LNO) buffer layers. YBCO films grown on an LNO buffer layer have only a slightly lower J c (5K, H=0) than films grown directly on a bare LaAlO 3 substrate. It is noteworthy that YBCO films grown on LNO buffer layers exhibit minor microstructural disorder and enhanced flux pinning. LNO-buffered Tl-2212 samples show large reductions in J c at all temperatures and fields compared to those grown on bare LaAlO 3 , correlating to both a-axis grain and nonsuperconducting phase formation. With additional optimization, LNO could be a promising buffer layer for both YBCO and Tl-based superconducting films, perhaps ideally suited for coated conductor applications

  7. Improvement of critical current density in thallium-based (Tl,Bi)Sr{sub 1.6}Ba{sub 0.4}Ca{sub 2}Cu{sub 3}O{sub x} superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Z.F.; Wang, C.A.; Wang, J.H. [State Univ. of New York at Buffalo, Amherst, NY (United States)] [and others

    1994-12-31

    Epitaxial (Tl,Bi)Sr{sub 1.6}Ba{sub 0.4}Ca{sub 2}Cu{sub 3}O{sub x} (Tl,Bi)-1223 thin films on (100) single crystal LaAlO{sub 3} substrates were synthesized by a two-step procedure. Phase development, microstructure, and relationships between film and substrate were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Resistance versus temperature, zero-field-cooled and field-cooled magnetization, and transport critical current density (J{sub c}) were measured. The zero-resistance temperature was 105-111 K. J{sub c} at 77 K and zero field was > 2 x 10{sup 6} A/cm{sup 2}. The films exhibited good flux pinning properties.

  8. Physical conditions in CaFe interstellar clouds

    OpenAIRE

    Gnacinski, P.; Krogulec, M.

    2007-01-01

    Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.

  9. Role of A-site Ca and B-site Zr substitution in BaTiO3 lead-free compounds: Combined experimental and first principles density functional theoretical studies

    Science.gov (United States)

    Keswani, Bhavna C.; Saraf, Deepashri; Patil, S. I.; Kshirsagar, Anjali; James, A. R.; Kolekar, Y. D.; Ramana, C. V.

    2018-05-01

    We report on the combined experimental and theoretical simulation results of lead-free ferroelectrics, Ba(1-x)CaxTiO3 (x = 0.0-0.3) and BaTi(1-y)ZryO3 (y = 0.0-0.2), synthesized by standard solid state reaction method. First principles density functional calculations are used to investigate the electronic structure, dynamical charges, and spontaneous polarization of these compounds. In addition, the structural, ferroelectric, piezoelectric, and dielectric properties are studied using extensive experiments. The X-ray diffraction and temperature dependent Raman spectroscopy studies indicate that the calcium (Ca) substituted compositions exhibit a single phase crystal structure, while zirconium (Zr) substituted compositions are biphasic. The scanning electron micrographs reveal the uniform and highly dense microstructure. The presence of polarization-electric field and strain-electric field hysteresis loops confirms the ferroelectric and piezoelectric nature of all the compositions. Our results demonstrate higher values for polarization, percentage strain, piezoelectric coefficients, and electrostrictive coefficient compared to those existing in the literature. For smaller substitutions of Ca and Zr in BaTiO3, a direct piezoelectric coefficient (d33) is enhanced, while the highest d33 value (˜300 pC/N) is observed for BaTi0.96Zr0.04O3 due to the biphasic ferroelectric behavior. Calculation of Born effective charges indicates that doping with Ca or Zr increases the dynamical charges on Ti as well as on O and decreases the dynamical charge on Ba. An increase in the dynamical charges on Ti and O is ascribed to the increase in covalency of Ti-O bond that reduces the polarizability of the crystal. A broader range of temperatures is demonstrated to realize the stable phase in the Ca substituted compounds. The results indicate enhancement in the temperature range of applicability of these compounds for device applications. The combined theoretical and experimental study is

  10. Investigation of inter-grain critical current density in Bi2Sr2CaCu2O8+δ superconducting wires and its relationship with the heat treatment protocol

    Science.gov (United States)

    Pallecchi, I.; Leveratto, A.; Braccini, V.; Zunino, V.; Malagoli, A.

    2017-09-01

    In this work we investigate the effect of each different heat treatment stage in the fabrication of Bi2Sr2CaCu2O8+δ superconducting wires on intra-grain and inter-grain superconducting properties. We measure magnetic critical temperature T c values and transport critical current density J c at temperatures from 4 K to 40 K and in fields up to 7 T. From an analysis of the temperature dependence of the self-field critical current density J c(T) that takes into account weak link behavior and the proximity effect, we study grain boundary (GB) transparency to supercurrents; we also establish a relationship between GB oxygenation in the different steps of the fabrication process and GB transparency to supercurrents. We find that GB oxygenation starts in the first crystallization stage, but it becomes complete in the plateau at 836 °C and in slow cooling stages and is further enhanced in the prolonged post-annealing step. Such oxygenation makes GBs more conductive, thus improving the inter-grain J c value and temperature dependence. On the other hand, from inspection of the T c values in the framework of the phase diagram dome, we find that grains are already oxygenated in the crystallization step up to the optimal doping, while successive slow cooling and post-annealing treatments further enhance the degree of overdoping, especially if carried out in oxygen atmosphere rather than in air.

  11. Mid-life environmental enrichment increases synaptic density in CA1 in a mouse model of Aβ-associated pathology and positively influences synaptic and cognitive health in healthy ageing.

    Science.gov (United States)

    Stuart, Kimberley E; King, Anna E; Fernandez-Martos, Carmen M; Dittmann, Justin; Summers, Mathew J; Vickers, James C

    2017-06-01

    Early-life cognitive enrichment may reduce the risk of experiencing cognitive deterioration and dementia in later-life. However, an intervention to prevent or delay dementia is likely to be taken up in mid to later-life. Hence, we investigated the effects of environmental enrichment in wildtype mice and in a mouse model of Aβ neuropathology (APP SWE /PS1 dE9 ) from 6 months of age. After 6 months of housing in standard laboratory cages, APP SWE /PS1 dE9 (n = 27) and healthy wildtype (n = 21) mice were randomly assigned to either enriched or standard housing. At 12 months of age, wildtype mice showed altered synaptic protein levels and relatively superior cognitive performance afforded by environmental enrichment. Environmental enrichment was not associated with alterations to Aβ plaque pathology in the neocortex or hippocampus of APP SWE /PS1 dE9 mice. However, a significant increase in synaptophysin immunolabeled puncta in the hippocampal subregion, CA1, in APP SWE /PS1 dE9 mice was detected, with no significant synaptic density changes observed in CA3, or the Fr2 region of the prefrontal cortex. Moreover, a significant increase in hippocampal BDNF was detected in APP SWE /PS1 dE9 mice exposed to EE, however, no changes were detected in neocortex or between Wt animals. These results demonstrate that mid to later-life cognitive enrichment has the potential to promote synaptic and cognitive health in ageing, and to enhance compensatory capacity for synaptic connectivity in pathological ageing associated with Aβ deposition. © 2017 Wiley Periodicals, Inc.

  12. Forebrain CRF1 Modulates Early-Life Stress-Programmed Cognitive Deficits

    Science.gov (United States)

    Wang, Xiao-Dong; Rammes, Gerhard; Kraev, Igor; Wolf, Miriam; Liebl, Claudia; Scharf, Sebastian H.; Rice, Courtney J.; Wurst, Wolfgang; Holsboer, Florian; Deussing, Jan M.; Baram, Tallie Z.; Stewart, Michael G.; Müller, Marianne B.; Schmidt, Mathias V.

    2012-01-01

    Childhood traumatic events hamper the development of the hippocampus and impair declarative memory in susceptible individuals. Persistent elevations of hippocampal corticotropin-releasing factor (CRF), acting through CRF receptor 1 (CRF1), in experimental models of early-life stress have suggested a role for this endogenous stress hormone in the resulting structural modifications and cognitive dysfunction. However, direct testing of this possibility has been difficult. In the current study, we subjected conditional forebrain CRF1 knock-out (CRF1-CKO) mice to an impoverished postnatal environment and examined the role of forebrain CRF1 in the long-lasting effects of early-life stress on learning and memory. Early-life stress impaired spatial learning and memory in wild-type mice, and postnatal forebrain CRF overexpression reproduced these deleterious effects. Cognitive deficits in stressed wild-type mice were associated with disrupted long-term potentiation (LTP) and a reduced number of dendritic spines in area CA3 but not in CA1. Forebrain CRF1 deficiency restored cognitive function, LTP and spine density in area CA3, and augmented CA1 LTP and spine density in stressed mice. In addition, early-life stress differentially regulated the amount of hippocampal excitatory and inhibitory synapses in wild-type and CRF1-CKO mice, accompanied by alterations in the neurexin-neuroligin complex. These data suggest that the functional, structural and molecular changes evoked by early-life stress are at least partly dependent on persistent forebrain CRF1 signaling, providing a molecular target for the prevention of cognitive deficits in adults with a history of early-life adversity. PMID:21940453

  13. LaNiO(3) Buffer Layers for High Critical Current Density YBa(2)Cu(3)O(7-delta) and Tl(2)Ba(2)CaCu(2)O(8-delta) Films

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, C.M.; Parilla, P.A.; Siegal, M.P.; Ginley, D.S.; Wang, Y.-T.; Blaugher, R.D.; Price, J.C.; Overmyer, D.L.; Venturini, E.L.

    1999-08-24

    We demonstrate high critical current density superconducting films of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) and Tl{sub 2}Ba{sub 2}CaCu{sub 2}O{sub 8{minus}{delta}} (Tl-2212) using LaNiO{sub 3} (LNO) buffer layers. YBCO films grown on an LNO buffer layer have only a slightly lower J{sub c} (5K, H=0) than films grown directly on a bare LaAlO{sub 3} substrate. It is noteworthy that YBCO films grown on LNO buffer layers exhibit minor microstructural disorder and enhanced flux pinning. LNO-buffered Tl-2212 samples show large reductions in J{sub c} at all temperatures and fields compared to those grown on bare LaAlO{sub 3}, correlating to both a-axis grain and nonsuperconducting phase formation. With additional optimization, LNO could be a promising buffer layer for both YBCO and Tl-based superconducting films, perhaps ideally suited for coated conductor applications.

  14. Temperature dependence of the hole density in high-T{sub C} superconductors Bi{sub 2−y}Pb{sub y}Sr{sub 2}CaCu{sub 2}O{sub 8+δ}

    Energy Technology Data Exchange (ETDEWEB)

    Ghafari, A. [Institute of Physics, Humboldt University of Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Janowitz, C., E-mail: janowitz@physik.hu-berlin.de [Institute of Physics, Humboldt University of Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Ariffin, A.K. [Institute of Physics, Humboldt University of Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Dep. of Physics, Universiti Pendidikan Sultan Idris, 35900 Tanjong Malim (Malaysia); Dwelk, H.; Krapf, A.; Manzke, R. [Institute of Physics, Humboldt University of Berlin, Newtonstr. 15, D-12489 Berlin (Germany)

    2013-02-14

    Highlights: ► We have done x-ray absorption spectra on the CuL{sub 3} edge of Bi(Pb)-2212 cuprates. ► We have measured the hole density n{sub H} in the CuO{sub 2} plane of Bi(Pb)-2212 cuprates. ► The measurements were performed from 10 K to 300 K. ► Gor’kov and Teitel’baums formula of n{sub H} consists of a linear and an exponential term. ► We have extended the Gor’kov and Teitel baum formula by a T{sup 3/2} term. -- Abstract: One of the most puzzling anomalies of high-T{sub C} cuprates is the strong temperature dependence of the Hall coefficient (R{sub H}) and the hole density (n{sub H}). Gor’kov and Teitel’baum (GT) proposed by using experimental data of La{sub 2−x}Sr{sub x}CuO{sub 4} (LSCO) a two fluid model. The number of holes per Cu atom n{sub H}, changes with temperature according to n{sub H}(T,x) = n{sub 0}(x) + n{sub 1}(x)exp(−Δ(x)/T) [1]. To clarify the temperature dependence of n{sub H} we have determined n{sub H} from X-ray absorption spectra (XAS) at the CuL{sub 3} edge for nearly optimum and slightly underdoped Bi{sub 2−y}Pb{sub y}Sr{sub 2}CaCu{sub 2}O{sub 8+δ} single crystals yielding directly the absolute value of n{sub H} in the CuO{sub 2} planes and also its change with temperature n{sub H}(T). It shows pronounced structures between 10 K and 300 K. The temperature dependence puts constraints to the applicability of previously developed models: (i) the two-band model without any explicit temperature dependence and (ii) the formula of GT, because the latter is not able to fit our data over the whole temperature range from 10 K to 300 K. Instead the thermal behavior of n{sub H} proposes a function with at least three terms, i.e. a third term added to the formula of GT is of exponential form ∼T{sup 3/2}.

  15. Metaheuristics-Assisted Combinatorial Screening of Eu2+-Doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N Compositional Space in Search of a Narrow-Band Green Emitting Phosphor and Density Functional Theory Calculations.

    Science.gov (United States)

    Lee, Jin-Woong; Singh, Satendra Pal; Kim, Minseuk; Hong, Sung Un; Park, Woon Bae; Sohn, Kee-Sun

    2017-08-21

    A metaheuristics-based design would be of great help in relieving the enormous experimental burdens faced during the combinatorial screening of a huge, multidimensional search space, while providing the same effect as total enumeration. In order to tackle the high-throughput powder processing complications and to secure practical phosphors, metaheuristics, an elitism-reinforced nondominated sorting genetic algorithm (NSGA-II), was employed in this study. The NSGA-II iteration targeted two objective functions. The first was to search for a higher emission efficacy. The second was to search for narrow-band green color emissions. The NSGA-II iteration finally converged on BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors in the Eu 2+ -doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N compositional search space. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor, which was synthesized with no human intervention via the assistance of NSGA-II, was a clear single phase and gave an acceptable luminescence. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor as well as all other phosphors that appeared during the NSGA-II iterations were examined in detail by employing powder X-ray diffraction-based Rietveld refinement, X-ray absorption near edge structure, density functional theory calculation, and time-resolved photoluminescence. The thermodynamic stability and the band structure plausibility were confirmed, and more importantly a novel approach to the energy transfer analysis was also introduced for BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors.

  16. Chronic caffeine consumption prevents cognitive decline from young to middle age in rats, and is associated with increased length, branching, and spine density of basal dendrites in CA1 hippocampal neurons.

    Science.gov (United States)

    Vila-Luna, S; Cabrera-Isidoro, S; Vila-Luna, L; Juárez-Díaz, I; Bata-García, J L; Alvarez-Cervera, F J; Zapata-Vázquez, R E; Arankowsky-Sandoval, G; Heredia-López, F; Flores, G; Góngora-Alfaro, J L

    2012-01-27

    Chronic caffeine consumption has been inversely associated with the risk of developing dementia and Alzheimer's disease. Here we assessed whether chronic caffeine treatment prevents the behavioral and cognitive decline that male Wistar rats experience from young (≈3 months) to middle age (≈10 months). When animals were young they were evaluated at weekly intervals in three tests: motor activity habituation in the open field (30-min sessions at the same time on consecutive days), continuous spontaneous alternation in the Y-maze (8 min), and elevated plus-maze (5 min). Afterward, rats from the same litter were randomly assigned either to a caffeine-treated group (n=13) or a control group (n=11), which received only tap water. Caffeine treatment (5 mg/kg/day) began when animals were ≈4 months old, and lasted for 6 months. Behavioral tests were repeated from day 14 to day 28 after caffeine withdrawal, a time period that is far in excess for the full excretion of a caffeine dose in this species. Thirty days after caffeine discontinuation brains were processed for Golgi-Cox staining. Compared with controls, we found that middle-aged rats that had chronically consumed low doses of caffeine (1) maintained their locomotor habituation during the second consecutive day exposure to the open field (an index of non-associative learning), (2) maintained their exploratory drive to complete the conventional minimum of nine arm visits required to calculate the alternation performance in the Y-maze in a greater proportion, (3) maintained their alternation percentage above chance level (an index of working memory), and (4) did not increase the anxiety indexes assessed by measuring the time spent in the open arms of the elevated plus maze. In addition, morphometric analysis of hippocampal neurons revealed that dendritic branching (90-140 μm from the soma), length of 4th and 5th order branches, total dendritic length, and spine density in distal dendritic branches were greater in

  17. Physical activity, body mass index and bone mineral density-associations in a prospective population-based cohort of women and men: the Canadian Multicentre Osteoporosis Study (CaMos).

    Science.gov (United States)

    Langsetmo, L; Hitchcock, C L; Kingwell, E J; Davison, K S; Berger, C; Forsmo, S; Zhou, W; Kreiger, N; Prior, J C

    2012-01-01

    Physical activity (PA) is an important modifiable risk factor for both bone mineral density (BMD) and body mass index (BMI). However, BMI is itself strongly predictive of BMD. Our aim was to determine the association between PA and BMD, with consideration of BMI as a potential mediating factor. The Canadian Multicentre Osteoporosis Study (CaMos) is a population-based prospective cohort study of Canadian women and men. PA was determined from interviewer-administered questionnaires at baseline and Year 5 and summarized as daily energy expenditure in total metabolic equivalents of the task multiplied by minutes/day (MET*m/d). Height, weight, and total hip and lumbar spine BMD were measured at baseline and Year 5. General linear models assessed relationships between PA and BMD, both cross-sectionally (baseline PA with baseline BMD) and longitudinally (average PA and change in PA with change in BMD). BMI was considered as a mediating factor. Potential confounders included age, center, education, caffeine intake, alcohol exposure, smoking history, history of weight-cycling, age at menarche, past use of oral contraceptives, history of >3 months missed menstruation, menopausal status, and antiresorptive use, as relevant. The study included 2855 men and 6442 women. PA was inversely associated with BMI at baseline, and an increase in PA between baseline and Year 5 was associated with a decrease in BMI, with 0.41 (95% CI: 0.22, 0.60) kg/m(2) loss per 1000 MET*m/d increase (in men) and 0.40 (95% CI: 0.23, 0.57) kg/m(2) loss per 1000 MET*m/d increase (in women). BMI was strongly associated with BMD, both cross-sectionally and longitudinally. However, increased PA was associated with a small increase in total hip BMD, 0.004 (95% CI: 0.000-0.008) g/cm(2) per 1000 MET*m/d (in men) and 0.003 (95% CI: 0.000-0.007) g/cm(2) per 1000 MET*m/d (in women). Average PA was associated with an increase in lumbar spine BMD in women, but not in men; it was not associated with change in total

  18. CREB Overexpression Ameliorates Age-related Behavioral and Biophysical Deficits

    Science.gov (United States)

    Yu, Xiao-Wen

    Age-related cognitive deficits are observed in both humans and animals. Yet, the molecular mechanisms underlying these deficits are not yet fully elucidated. In aged animals, a decrease in intrinsic excitability of pyramidal neurons from the CA1 sub-region of hippocampus is believed to contribute to age-related cognitive impairments, but the molecular mechanism(s) that modulate both these factors has yet to be identified. Increasing activity of the transcription factor cAMP response element-binding protein (CREB) in young adult rodents has been shown to facilitate cognition, and increase intrinsic excitability of their neurons. However, how CREB changes with age, and how that impacts cognition in aged animals, is not clear. Therefore, we first systematically characterized age- and training-related changes in CREB levels in dorsal hippocampus. At a remote time point after undergoing behavioral training, levels of total CREB and activated CREB (phosphorylated at S133, pCREB) were measured in both young and aged rats. We found that pCREB, but not total CREB was significantly reduced in dorsal CA1 of aged rats. Importantly, levels of pCREB were found to be positively correlated with short-term spatial memory in both young and aged rats i.e. higher pCREB in dorsal CA1 was associated with better spatial memory. These findings indicate that an age-related deficit in CREB activity may contribute to the development of age-related cognitive deficits. However, it was still unclear if increasing CREB activity would be sufficient to ameliorate age-related cognitive, and biophysical deficits. To address this question, we virally overexpressed CREB in CA1, where we found the age-related deficit. Young and aged rats received control or CREB virus, and underwent water maze training. While control aged animals exhibited deficits in long-term spatial memory, aged animals with CREB overexpression performed at levels comparable to young animals. Concurrently, aged neurons

  19. BDNF Regains Function in Hippocampal Long-Term Potentiation Deficits Caused by Diencephalic Damage

    Science.gov (United States)

    Vedder, Lindsey C.; Savage, Lisa M.

    2017-01-01

    Thiamine deficiency (TD), commonly associated with chronic alcoholism, leads to diencephalic damage, hippocampal dysfunction, and spatial learning and memory deficits. We show a decrease in the magnitude of long-term potentiation (LTP) and paired-pulse facilitation (PPF) at CA3-CA1 synapses, independent of sex, following diencephalic damage…

  20. Attention deficit hyperactivity disorder (ADHD)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001551.htm Attention deficit hyperactivity disorder To use the sharing features on this page, please enable JavaScript. Attention deficit hyperactivity disorder (ADHD) is a problem caused by ...

  1. Long-term fluoxetine treatment induces input-specific LTP and LTD impairment and structural plasticity in the CA1 hippocampal subfield.

    Directory of Open Access Journals (Sweden)

    Francisco J Rubio

    2013-05-01

    Full Text Available Antidepressant drugs are usually administered for long time for the treatment of major depressive disorder. However, they are also prescribed in several additional psychiatric conditions as well as during long term maintenance treatments. Antidepressants induce adaptive changes in several forebrain structures which include modifications at glutamatergic synapses. We recently found that repetitive administration of the selective serotonin reuptake inhibitor fluoxetine to naϊve adult male rats induced an increase of mature, mushroom-type dendritic spines in several forebrain regions. This was associated with an increase of GluA2-containing α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptors (AMPA-Rs in telencephalic postsynaptic densities. To unravel the functional significance of such a synaptic re-arrangement, we focused on glutamate neurotransmission in the hippocampus. We evaluated the effect of four weeks of treatment with 0.7 mg/kg of fluoxetine on long-term potentiation (LTP and long-term depression (LTD in the Schaffer collateral-CA1 synapses and the perforant path-CA1 synapses. Recordings in hippocampal slices revealed profound deficits in LTP and LTD at Schaffer collateral-CA1 synapses associated to increased spine density and enhanced presence of mushroom-type spines, as revealed by Golgi staining. However, the same treatment had neither an effect on spine morphology, nor on LTP and LTD at perforant path-CA1 synapses. Cobalt staining experiments revealed decreased AMPA-R Ca2+ permeability in the stratum radiatum together with increased GluA2-containing, Ca2+-impermeable AMPA-Rs. Therefore, 4 weeks of fluoxetine treatment promoted structural and functional adaptations in CA1 neurons in a pathway-specific manner that were selectively associated with impairment of activity-dependent plasticity at Schaffer collateral-CA1 synapses.

  2. Metallic Burden of Deciduous Teeth and Childhood Behavioral Deficits

    Directory of Open Access Journals (Sweden)

    Tony J.H. Chan

    2015-06-01

    Full Text Available Attention Deficit/Hyperactivity Disorder (ADHD affects 5%–8% of children in the U.S. (10% of males and 4% of females. The contributions of multiple metal exposures to the childhood behavioral deficits are unclear, although particular metals have been implicated through their neurotoxicity. The objective of this study was to test the hypothesis that the body burden of Mn is positively correlated with ADHD symptoms. We also investigated the putative roles of Ca, Fe, Pb, and Hg. We collected shed molars from 266 children (138 boys and 128 girls who lost a tooth between 11 and 13 years of age. The molars were analyzed for metals using ICP-OES. The third grade teacher of each child completed the Teacher’s Disruptive Behavior Disorders Rating Scale (DBD to produce a score for “Total Disruptive Behavior” and subscale scores for “Attention Deficit Hyperactivity Disorder”, Hyperactivity/Impulsivity, Inattention, and Oppositional/Defiant. The mean Mn, Fe, Pb and Ca concentrations found in teeth was 6.1 ± 5.7 µg/g, 22.7 ± 24.1 µg/g, 0.9 ± 1.4 µg/g, and 6.0 × 105 ± 1.6 × 105 µg/g, respectively. Hg was not detected. No significant association was found between Mn and behavioral deficits. Ca was significantly negatively associated, and Pb showed a significant positive association with Hyperactivity/Impulsivity, Inattention, and Oppositional/Defiant Disorders. These findings call into question the putative independent association of manganese exposure and behavioral deficits in children, when the balance of other metallic burden, particularly Ca and Pb burdens play significant roles.

  3. Beyond the knowledge deficit

    DEFF Research Database (Denmark)

    Hansen, Janus Staffan; Holm, Lotte; Frewer, Lynn

    2003-01-01

    The paper reviews psychological and social scientific research on lay attitudes to food risks. Many experts (scientists, food producers and public health advisors) regard public unease about food risks as excessive. This expert-lay discrepancy is often attributed to a 'knowledge deficit' among la...... in institutions and experts. It suggests that an interdisciplinary, contextualised and psychologically sound approach to the study of risk is needed.......The paper reviews psychological and social scientific research on lay attitudes to food risks. Many experts (scientists, food producers and public health advisors) regard public unease about food risks as excessive. This expert-lay discrepancy is often attributed to a 'knowledge deficit' among lay...... people. However, much research in psychology and sociology suggests that lay risk assessments are complex, situationally sensitive expressions of personal value systems. The paper is organised around four themes: risk perception, the communication of risk, lay handling of risk, and public trust...

  4. Area deficits and the Bel–Robinson tensor

    Science.gov (United States)

    Jacobson, Ted; Senovilla, José M. M.; Speranza, Antony J.

    2018-04-01

    The first law of causal diamonds relates the area deficit of a small ball relative to flat space to the matter energy density it contains. At second order in the Riemann normal coordinate expansion, this energy density should receive contributions from the gravitational field itself. In this work, we study the second-order area deficit of the ball in the absence of matter and analyze its relation to possible notions of gravitational energy. In the small ball limit, a reasonable expectation for any proposed gravitational energy functional is that it evaluate to the Bel–Robinson energy density W in vacuum spacetimes. A direct calculation of the area deficit reveals a result that is not simply proportional to W. We discuss how the deviation from W is related to ambiguities in defining the shape of the ball in curved space, and provide several proposals for fixing these shape ambiguities.

  5. Attention Deficit Hyperactivity Disorder

    OpenAIRE

    Jaime O. Oliver

    2017-01-01

    Attention Deficit Hyperactivity Disorder (ADHD) is considered as among the most common yet serious brain disorders significant number of children are subjected to; the seriousness of which manifests in the ability of the disorder to continue to show up even after the childhood years, during the period of adolescence as well as adulthood. Considering the findings delivered by Brain Imaging Studies conducted on youth, it is revealed that people suffering from ADHD experiences del...

  6. Long term delivery of pulsed magnetic fields does not alter visual discrimination learning or dendritic spine density in the mouse CA1 pyramidal or dentate gyrus neurons [v2; ref status: indexed, http://f1000r.es/2gk

    Directory of Open Access Journals (Sweden)

    Matthew Sykes

    2013-12-01

    Full Text Available Repetitive transcranial magnetic stimulation (rTMS is thought to facilitate brain plasticity. However, few studies address anatomical changes following rTMS in relation to behaviour. We delivered 5 weeks of daily pulsed rTMS stimulation to adult ephrin-A2-/- and wildtype (C57BI/6j mice (n=10 per genotype undergoing a visual learning task and analysed learning performance, as well as spine density, in the dentate gyrus molecular and CA1 pyramidal cell layers in Golgi-stained brain sections. We found that neither learning behaviour, nor hippocampal spine density was affected by long term rTMS. Our negative results highlight the lack of deleterious side effects in normal subjects and are consistent with previous studies suggesting that rTMS has a bigger effect on abnormal or injured brain substrates than on normal/control structures.

  7. Attention deficits and divorce.

    Science.gov (United States)

    Bouchard, Geneviève; Saint-Aubin, Jean

    2014-09-01

    Building on previous work on the role of attention deficits associated with the regulation of executive control in psychiatric disorders, we examine whether these attention deficits are related to an interpersonal disturbance, the experience of divorce. Attentional capacities of 95 randomly selected couples from the general population were measured with a well-established task, the Attentional Network Task, which assesses the efficiency of 3 attention networks (that is, alerting, orienting, and executive control). Among the 190 participants, 32 had experienced a divorce in the past. ANCOVAs were used to compare divorced people in marital or cohabiting unions with people in first unions in their performance on this purely cognitive task. Our findings indicate that divorced people who are currently living in a cohabiting relationship show significantly lower executive control than other adults living as couples, after controlling for sex, age, income, and education. This subgroup of divorced people not only exhibit greater difficulty in responding to some stimuli while ignoring irrelevant ones but also manifest cognitive deficits in conflict resolution. This study highlights the links between attention and the long-term maintenance of intimate relationships. Our results may have important implications for the identification of people at risk for divorce.

  8. Ballistic deficit correction

    International Nuclear Information System (INIS)

    Duchene, G.; Moszynski, M.; Curien, D.

    1991-01-01

    The EUROGAM data-acquisition has to handle a large number of events/s. Typical in-beam experiments using heavy-ion fusion reactions assume the production of about 50 000 compound nuclei per second deexciting via particle and γ-ray emissions. The very powerful γ-ray detection of EUROGAM is expected to produce high-fold event rates as large as 10 4 events/s. Such high count rates introduce, in a common dead time mode, large dead times for the whole system associated with the processing of the pulse, its digitization and its readout (from the preamplifier pulse up to the readout of the information). In order to minimize the dead time the shaping time constant τ, usually about 3 μs for large volume Ge detectors has to be reduced. Smaller shaping times, however, will adversely affect the energy resolution due to ballistic deficit. One possible solution is to operate the linear amplifier, with a somewhat smaller shaping time constant (in the present case we choose τ = 1.5 μs), in combination with a ballistic deficit compensator. The ballistic deficit can be corrected in different ways using a Gated Integrator, a hardware correction or even a software correction. In this paper we present a comparative study of the software and hardware corrections as well as gated integration

  9. Electronic structures and magnetism of CaFeAsH and CaFeAsF

    International Nuclear Information System (INIS)

    Wang Guangtao; Shi Xianbiao; Liu Haipeng; Liu Qingbo

    2015-01-01

    We studied the electronic structures, magnetism, and Fermi surface (FS) nesting of CaFeAsH and CaFeAsF by first-principles calculations. In the nonmagnetic (NM) states, we found strong FS nesting, which induces magnetic instability and a spin density wave (SDW). Our calculations indicate that the ground state of CaFeAsH and CaFeAsF is the stripe antiferromagnetic state. The calculated bare susceptibility χ 0 (q) peaked at the M-point and was clearly suppressed and became slightly incommensurate with both electron doping and hole doping for both materials. (author)

  10. Increasing Northern Hemisphere water deficit

    Science.gov (United States)

    McCabe, Gregory J.; Wolock, David M.

    2015-01-01

    A monthly water-balance model is used with CRUTS3.1 gridded monthly precipitation and potential evapotranspiration (PET) data to examine changes in global water deficit (PET minus actual evapotranspiration) for the Northern Hemisphere (NH) for the years 1905 through 2009. Results show that NH deficit increased dramatically near the year 2000 during both the cool (October through March) and warm (April through September) seasons. The increase in water deficit near 2000 coincides with a substantial increase in NH temperature and PET. The most pronounced increases in deficit occurred for the latitudinal band from 0 to 40°N. These results indicate that global warming has increased the water deficit in the NH and that the increase since 2000 is unprecedented for the 1905 through 2009 period. Additionally, coincident with the increase in deficit near 2000, mean NH runoff also increased due to increases in P. We explain the apparent contradiction of concurrent increases in deficit and increases in runoff.

  11. BiCaSrCuO superconductors

    International Nuclear Information System (INIS)

    Polvi, V.M.; Niemi, K.J.

    1989-01-01

    BiCaSrCuO and BiPbCaSrCuO powders have been synthesized. Different research methods (SEM,EDS,XRF,SRD,DTA) have been used to characterize the bulk specimen and wires. Resistance and current density measured as a function of temperature are reported. The ceramic products contained several phases. Lead containing specimen gave the best results and the synthesis was easily reproducible

  12. Impact of seawater [Ca

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; Thoms, S.; Nehrke, G.; Reichart, G.J.; de Nooijer, L.J.; Bijma, J.

    2015-01-01

    Mg / Ca ratios in foraminiferal tests are routinely used as paleotemperature proxies, but on long timescales, they also hold the potential to reconstruct past seawater Mg / Ca. The impact of both temperature and seawater Mg / Ca on Mg incorporation in Foraminifera has been quantified by a number of

  13. Alterations of in vivo CA1 network activity in Dp(16)1Yey Down syndrome model mice.

    Science.gov (United States)

    Raveau, Matthieu; Polygalov, Denis; Boehringer, Roman; Amano, Kenji; Yamakawa, Kazuhiro; McHugh, Thomas J

    2018-02-27

    Down syndrome, the leading genetic cause of intellectual disability, results from an extra-copy of chromosome 21. Mice engineered to model this aneuploidy exhibit Down syndrome-like memory deficits in spatial and contextual tasks. While abnormal neuronal function has been identified in these models, most studies have relied on in vitro measures. Here, using in vivo recording in the Dp(16)1Yey model, we find alterations in the organization of spiking of hippocampal CA1 pyramidal neurons, including deficits in the generation of complex spikes. These changes lead to poorer spatial coding during exploration and less coordinated activity during sharp-wave ripples, events involved in memory consolidation. Further, the density of CA1 inhibitory neurons expressing neuropeptide Y, a population key for the generation of pyramidal cell bursts, were significantly increased in Dp(16)1Yey mice. Our data refine the 'over-suppression' theory of Down syndrome pathophysiology and suggest specific neuronal subtypes involved in hippocampal dysfunction in these model mice. © 2018, Raveau et al.

  14. Hydrocephalus compacted cortex and hippocampus and altered their output neurons in association with spatial learning and memory deficits in rats.

    Science.gov (United States)

    Chen, Li-Jin; Wang, Yueh-Jan; Chen, Jeng-Rung; Tseng, Guo-Fang

    2017-07-01

    Hydrocephalus is a common neurological disorder in children characterized by abnormal dilation of cerebral ventricles as a result of the impairment of cerebrospinal fluid flow or absorption. Clinical presentation of hydrocephalus varies with chronicity and often shows cognitive dysfunction. Here we used a kaolin-induction method in rats and studied the effects of hydrocephalus on cerebral cortex and hippocampus, the two regions highly related to cognition. Hydrocephalus impaired rats' performance in Morris water maze task. Serial three-dimensional reconstruction from sections of the whole brain freshly froze in situ with skull shows that the volumes of both structures were reduced. Morphologically, pyramidal neurons of the somatosensory cortex and hippocampus appear to be distorted. Intracellular dye injection and subsequent three-dimensional reconstruction and analyses revealed that the dendritic arbors of layer III and V cortical pyramid neurons were reduced. The total dendritic length of CA1, but not CA3, pyramidal neurons was also reduced. Dendritic spine densities on both cortical and hippocampal pyramidal neurons were decreased, consistent with our concomitant findings that the expressions of both synaptophysin and postsynaptic density protein 95 were reduced. These cortical and hippocampal changes suggest reductions of excitatory connectivity, which could underlie the learning and memory deficits in hydrocephalus. © 2016 International Society of Neuropathology.

  15. Bone mineral density in diabetes mellitus patients with and without a Charcot foot

    DEFF Research Database (Denmark)

    Christensen, Tomas M; Bülow, Jens; Simonsen, Lene

    2010-01-01

    To measure bone mineral density in patients with diabetes mellitus and the complication Charcot osteoarthropathy (CA).......To measure bone mineral density in patients with diabetes mellitus and the complication Charcot osteoarthropathy (CA)....

  16. crdi.ca

    International Development Research Centre (IDRC) Digital Library (Canada)

    et des enfants d'Afrique. INITIATIVE CONCERTÉE. Innovation pour la santé des mères et des enfants d'Afrique. Centre de recherches pour le développement international. CP Box 8500 Ottawa ON Canada K1G 3H9. Téléphone : +1 613 236 6163 • Télécopieur : +1 613 657 7749 ismea@crdi.ca | www.crdi.ca/ismea crdi.ca.

  17. Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Matthews, Marguerite; Nigg, Joel T.

    2014-01-01

    Over the last two decades, there have been numerous technical and methodological advances available to clinicians and researchers to better understand attention deficit hyperactivity disorder (ADHD) and its etiology. Despite the growing body of literature investigating the disorder’s pathophysiology, ADHD remains a complex psychiatric disorder to characterize. This chapter will briefly review the literature on ADHD, with a focus on its history, the current genetic insights, neurophysiologic theories, and the use of neuroimaging to further understand the etiology. We address some of the major concerns that remain unclear about ADHD, including subtype instability, heterogeneity, and the underlying neural correlates that define the disorder. We highlight that the field of ADHD is rapidly evolving; the descriptions provided here will hopefully provide a sturdy foundation for which to build and improve our understanding of the disorder. PMID:24214656

  18. Road density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  19. INTRACELLULAR Ca2+ HOMEOSTASIS

    Directory of Open Access Journals (Sweden)

    Shahdevi Nandar Kurniawan

    2015-01-01

    Full Text Available Ca2+ signaling functions to regulate many cellular processes. Dynamics of Ca2+ signaling or homeostasis is regulated by the interaction between ON and OFF reactions that control Ca2+ flux in both the plasma membrane and internal organelles such as the endoplasmic reticulum (ER and mitochondria. External stimuli activate the ON reactions, which include Ca2+ into the cytoplasm either through channels in the plasma membrane or from internal storage like in ER. Most of the cells utilize both channels/sources, butthere area few cells using an external or internal source to control certain processes. Most of the Ca2+ entering the cytoplasm adsorbed to the buffer, while a smaller part activate effect or to stimulate cellular processes. Reaction OFF is pumping of cytoplasmic Ca2+ using a combination mechanism of mitochondrial and others. Changes in Ca2+ signal has been detected in various tissues isolated from animals induced into diabetes as well as patients with diabetes. Ca2+ signal interference is also found in sensory neurons of experimental animals with diabetes. Ca2+ signaling is one of the main signaling systems in the cell.

  20. Gray matter morphological anomalies in the cerebellar vermis in first-episode schizophrenia patients with cognitive deficits.

    Science.gov (United States)

    Wang, Jingjuan; Zhou, Li; Cui, Chunlei; Liu, Zhening; Lu, Jie

    2017-11-22

    Cognitive deficits are a core feature of early schizophrenia. However, the pathological foundations underlying cognitive deficits are still unknown. The present study examined the association between gray matter density and cognitive deficits in first-episode schizophrenia. Structural magnetic resonance imaging of the brain was performed in 34 first-episode schizophrenia patients and 21 healthy controls. Patients were divided into two subgroups according to working memory task performance. The three groups were well matched for age, gender, and education, and the two patient groups were also further matched for diagnosis, duration of illness, and antipsychotic treatment. Voxel-based morphometric analysis was performed to estimate changes in gray matter density in first-episode schizophrenia patients with cognitive deficits. The relationships between gray matter density and clinical outcomes were explored. Patients with cognitive deficits were found to have reduced gray matter density in the vermis and tonsil of cerebellum compared with patients without cognitive deficits and healthy controls, decreased gray matter density in left supplementary motor area, bilateral precentral gyrus compared with patients without cognitive deficits. Classifier results showed GMD in cerebellar vermis tonsil cluster could differentiate SZ-CD from controls, left supplementary motor area cluster could differentiate SZ-CD from SZ-NCD. Gray matter density values of the cerebellar vermis cluster in patients groups were positively correlated with cognitive severity. Decreased gray matter density in the vermis and tonsil of cerebellum may underlie early psychosis and serve as a candidate biomarker for schizophrenia with cognitive deficits.

  1. The relationship between proton pump inhibitor use and longitudinal change in bone mineral density: a population-based study [corrected] from the Canadian Multicentre Osteoporosis Study (CaMos).

    Science.gov (United States)

    Targownik, Laura E; Leslie, William D; Davison, K Shawn; Goltzman, David; Jamal, Sophie A; Kreiger, Nancy; Josse, Robert G; Kaiser, Stephanie M; Kovacs, Christopher S; Prior, Jerilynn C; Zhou, Wei

    2012-09-01

    Proton pump inhibitor (PPI) use has been identified as a risk factor for hip and vertebral fractures. Evidence supporting a relationship between PPI use and osteoporosis remains scant. Demonstrating that PPIs are associated with accelerated bone mineral density (BMD) loss would provide supportive evidence for a mechanism through which PPIs could increase fracture risk. We used the Canadian Multicentre Osteoporosis Study data set, which enrolled a population-based sample of Canadians who underwent BMD testing of the femoral neck, total hip, and lumbar spine (L1-L4) at baseline, and then again at 5 and 10 years. Participants also reported drug use and exposure to risk factors for osteoporosis and fracture. Multivariate linear regression was used to determine the independent association of PPI exposure and baseline BMD, and on change in BMD at 5 and 10 years. In all, 8,340 subjects were included in the baseline analysis, with 4,512 (55%) undergoing year 10 BMD testing. After adjusting for potential confounders, PPI use was associated with significantly lower baseline BMD at the femoral neck and total hip. PPI use was not associated with a significant acceleration in covariate-adjusted BMD loss at any measurement site after 5 and 10 years of follow-up. PPI users had lower BMD at baseline than PPI non-users, but PPI use over 10 years did not appear to be associated with accelerated BMD loss. The reasons for discordant findings between PPI use at baseline and during follow-up require further study.

  2. Pragmatic communication deficits in children with epilepsy

    NARCIS (Netherlands)

    Broeders, Mark; Geurts, Hilde; Jennekens-Schinkel, Aag

    2010-01-01

    Background: Various psychiatric and neurological disorders including epilepsy have been associated with language deficits. Pragmatic language deficits, however, have seldom been the focus of earlier studies in children with epilepsy. Moreover, it is unknown whether these pragmatic deficits are

  3. Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4 : Calculated dehydrogenation enthalpy, including zero point energy, and the structure of the phonon spectra

    NARCIS (Netherlands)

    Marashdeh, A.; Frankcombe, T.J.

    2008-01-01

    The dehydrogenation enthalpies of Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4 have been calculated using density functional theory calculations at the generalized gradient approximation level. Harmonic phonon zero point energy (ZPE) corrections have been included using Parlinski’s direct method. The

  4. Lung density

    DEFF Research Database (Denmark)

    Garnett, E S; Webber, C E; Coates, G

    1977-01-01

    The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...... breathing in the sitting position ranged from 0.25 to 0.37 g.cm-3. Subnormal values were found in patients with emphsema. In patients with pulmonary congestion and edema, lung density values ranged from 0.33 to 0.93 g.cm-3. The lung density measurement correlated well with the findings in chest radiographs...... but the lung density values were more sensitive indices. This was particularly evident in serial observations of individual patients....

  5. Structural characterization and electron density distribution studies of (La{sub 0.8}Ca{sub 0.2})(Cr{sub 0.9−x}Co{sub 0.1}Mn{sub x})O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, R. [Research Centre and Post Graduate Department of physics, The Madura College, Madurai 625011 (India); Thenmozhi, N., E-mail: thenmozhi.n6@gmail.com [PG and Research Department of Physics, NMSSVN College, Nagamalai, Madurai 625019 (India); Fu, Yen-Pei [Department of materials Science and Engineering, National Dong-Hwa University, Shou-Feng, Hualien 974, Taiwan (China)

    2016-07-15

    The doped lanthanum chromite (La{sub 0.8}Ca{sub 0.2})(Cr{sub 0.9−x}Co{sub 0.1}Mn{sub x})O{sub 3} (x=0.03, 0.06, 0.09 and 0.12) were synthesized by solid state reaction technique. The samples have been characterized by X-ray diffraction for structural and charge density analysis. XRD data show that the grown samples are orthorhombic in structure with single phase. The spatial charge density distribution in the unit cell for the synthesized samples has been studied using maximum entropy method. Further, the samples were analyzed by UV–visible spectrometry for optical properties and scanning electron microscopy for surface morphology. From the optical data, it was found that the direct band gap of the samples range from 2.27 to 2.46 eV. The samples were also investigated by vibrating sample magnetometry for magnetic properties. From VSM data, it is inferred that all the samples in this series are found to be predominantly antiferromagnetic in nature. Since the doped lanthanum chromites have good mechanical properties and electrical conductivity at high temperature, these materials are used in solid oxide fuel cells (SOFC).

  6. Ab-initio calculations of the Ruddlesden-Popper phases CaMnO3, CaO(CaMnO3) and CaO(CaMnO3)2

    International Nuclear Information System (INIS)

    Cardoso, C; Borges, R P; Gasche, T; Godinho, M

    2008-01-01

    The present work reports ab-initio density functional theory calculations for the Ruddlesden-Popper phase CaO(CaMnO 3 ) n compounds. In order to study the evolution of the properties with the number of perovskite layers, a detailed analysis of the densities of states calculated for each compound and for several magnetic configurations was performed. The effect of distortions of the crystal structure on the magnetic ground state is also analysed and the exchange constants and transition temperatures are calculated for the three compounds using a mean field model. The calculated magnetic ground state structures and magnetic moments are in good agreement with experimental results and previous calculations

  7. Pyk2 modulates hippocampal excitatory synapses and contributes to cognitive deficits in a Huntington’s disease model

    KAUST Repository

    Giralt, Albert; Brito, Veronica; Chevy, Quentin; Simonnet, Clé mence; Otsu, Yo; Cifuentes-Dí az, Carmen; Pins, Benoit de; Coura, Renata; Alberch, Jordi; Giné s, Sí lvia; Poncer, Jean-Christophe; Girault, Jean-Antoine

    2017-01-01

    The structure and function of spines and excitatory synapses are under the dynamic control of multiple signalling networks. Although tyrosine phosphorylation is involved, its regulation and importance are not well understood. Here we study the role of Pyk2, a non-receptor calcium-dependent protein-tyrosine kinase highly expressed in the hippocampus. Hippocampal-related learning and CA1 long-term potentiation are severely impaired in Pyk2-deficient mice and are associated with alterations in NMDA receptors, PSD-95 and dendritic spines. In cultured hippocampal neurons, Pyk2 has autophosphorylation-dependent and -independent roles in determining PSD-95 enrichment and spines density. Pyk2 levels are decreased in the hippocampus of individuals with Huntington and in the R6/1 mouse model of the disease. Normalizing Pyk2 levels in the hippocampus of R6/1 mice rescues memory deficits, spines pathology and PSD-95 localization. Our results reveal a role for Pyk2 in spine structure and synaptic function, and suggest that its deficit contributes to Huntington’s disease cognitive impairments.

  8. Pyk2 modulates hippocampal excitatory synapses and contributes to cognitive deficits in a Huntington’s disease model

    KAUST Repository

    Giralt, Albert

    2017-05-30

    The structure and function of spines and excitatory synapses are under the dynamic control of multiple signalling networks. Although tyrosine phosphorylation is involved, its regulation and importance are not well understood. Here we study the role of Pyk2, a non-receptor calcium-dependent protein-tyrosine kinase highly expressed in the hippocampus. Hippocampal-related learning and CA1 long-term potentiation are severely impaired in Pyk2-deficient mice and are associated with alterations in NMDA receptors, PSD-95 and dendritic spines. In cultured hippocampal neurons, Pyk2 has autophosphorylation-dependent and -independent roles in determining PSD-95 enrichment and spines density. Pyk2 levels are decreased in the hippocampus of individuals with Huntington and in the R6/1 mouse model of the disease. Normalizing Pyk2 levels in the hippocampus of R6/1 mice rescues memory deficits, spines pathology and PSD-95 localization. Our results reveal a role for Pyk2 in spine structure and synaptic function, and suggest that its deficit contributes to Huntington’s disease cognitive impairments.

  9. Cytomorphometric changes in hippocampal CA1 neurons exposed to simulated microgravity using rats as model

    Directory of Open Access Journals (Sweden)

    Amit eRanjan

    2014-05-01

    Full Text Available Microgravity and sleep loss lead to cognitive and learning deficits. These behavioral alterations are likely to be associated with cytomorphological changes and loss of neurons. To understand the phenomenon, we exposed rats (225-275g to 14 days simulated microgravity (SMg and compared its effects on CA1 hippocampal neuronal plasticity, with that of normal cage control rats. We observed that the mean area, perimeter, synaptic cleft and length of active zone of CA1 hippocampal neurons significantly decreased while dendritic arborization and number of spines significantly increased in SMg group as compared with controls. The mean thickness of the post synaptic density and total dendritic length remained unaltered. The changes may be a compensatory effect induced by exposure to microgravity; however, the effects may be transient or permanent, which need further study. These findings may be useful for designing effective prevention for those, including the astronauts, exposed to microgravity. Further, subject to confirmation we propose that SMg exposure might be useful for recovery of stroke patients.

  10. Targeting Cardiomyocyte Ca2+ Homeostasis in Heart Failure

    Science.gov (United States)

    Røe, Åsmund T.; Frisk, Michael; Louch, William E.

    2015-01-01

    Improved treatments for heart failure patients will require the development of novel therapeutic strategies that target basal disease mechanisms. Disrupted cardiomyocyte Ca2+ homeostasis is recognized as a major contributor to the heart failure phenotype, as it plays a key role in systolic and diastolic dysfunction, arrhythmogenesis, and hypertrophy and apoptosis signaling. In this review, we outline existing knowledge of the involvement of Ca2+ homeostasis in these deficits, and identify four promising targets for therapeutic intervention: the sarcoplasmic reticulum Ca2+ ATPase, the Na+-Ca2+ exchanger, the ryanodine receptor, and t-tubule structure. We discuss experimental data indicating the applicability of these targets that has led to recent and ongoing clinical trials, and suggest future therapeutic approaches. PMID:25483944

  11. Activation of PPARγ Ameliorates Spatial Cognitive Deficits through Restoring Expression of AMPA Receptors in Seipin Knock-Out Mice.

    Science.gov (United States)

    Zhou, Libin; Chen, Tingting; Li, Guoxi; Wu, Chaoming; Wang, Conghui; Li, Lin; Sha, Sha; Chen, Lei; Liu, George; Chen, Ling

    2016-01-27

    A characteristic phenotype of congenital generalized lipodystrophy 2 (CGL2) that is caused by loss-of-function of seipin gene is mental retardation. Here, we show that seipin deficiency in hippocampal CA1 pyramidal cells caused the reduction of peroxisome proliferator-activated receptor gamma (PPARγ). Twelve-week-old systemic seipin knock-out mice and neuronal seipin knock-out (seipin-nKO) mice, but not adipose seipin knock-out mice, exhibited spatial cognitive deficits as assessed by the Morris water maze and Y-maze, which were ameliorated by the treatment with the PPARγ agonist rosiglitazone (rosi). In addition, seipin-nKO mice showed the synaptic dysfunction and the impairment of NMDA receptor-dependent LTP in hippocampal CA1 regions. The density of AMPA-induced current (IAMPA) in CA1 pyramidal cells and GluR1/GluR2 expression were significantly reduced in seipin-nKO mice, whereas the NMDA-induced current (INMDA) and NR1/NR2 expression were not altered. Rosi treatment in seipin-nKO mice could correct the decrease in expression and activity of AMPA receptor (AMPAR) and was accompanied by recovered synaptic function and LTP induction. Furthermore, hippocampal ERK2 and CREB phosphorylation in seipin-nKO mice were reduced and this could be rescued by rosi treatment. Rosi treatment in seipin-nKO mice elevated BDNF concentration. The MEK inhibitor U0126 blocked rosi-restored AMPAR expression and LTP induction in seipin-nKO mice, but the Trk family inhibitor K252a did not. These findings indicate that the neuronal seipin deficiency selectively suppresses AMPAR expression through reducing ERK-CREB activities, leading to the impairment of LTP and spatial memory, which can be rescued by PPARγ activation. Congenital generalized lipodystrophy 2 (CGL2), caused by loss-of-function mutation of seipin gene, is characterized by mental retardation. By the generation of systemic or neuronal seipin knock-out mice, the present study provides in vivo evidence that neuronal seipin

  12. Visual search deficits in amblyopia.

    Science.gov (United States)

    Tsirlin, Inna; Colpa, Linda; Goltz, Herbert C; Wong, Agnes M F

    2018-04-01

    Amblyopia is a neurodevelopmental disorder defined as a reduction in visual acuity that cannot be corrected by optical means. It has been associated with low-level deficits. However, research has demonstrated a link between amblyopia and visual attention deficits in counting, tracking, and identifying objects. Visual search is a useful tool for assessing visual attention but has not been well studied in amblyopia. Here, we assessed the extent of visual search deficits in amblyopia using feature and conjunction search tasks. We compared the performance of participants with amblyopia (n = 10) to those of controls (n = 12) on both feature and conjunction search tasks using Gabor patch stimuli, varying spatial bandwidth and orientation. To account for the low-level deficits inherent in amblyopia, we measured individual contrast and crowding thresholds and monitored eye movements. The display elements were then presented at suprathreshold levels to ensure that visibility was equalized across groups. There was no performance difference between groups on feature search, indicating that our experimental design controlled successfully for low-level amblyopia deficits. In contrast, during conjunction search, median reaction times and reaction time slopes were significantly larger in participants with amblyopia compared with controls. Amblyopia differentially affects performance on conjunction visual search, a more difficult task that requires feature binding and possibly the involvement of higher-level attention processes. Deficits in visual search may affect day-to-day functioning in people with amblyopia.

  13. A Proper Perspective on the Twin Deficits

    Science.gov (United States)

    1989-05-01

    deficit twins, the relation between them, and their consanguine parentage. The trade deficit or, to be more accurate, the current account deficit, is...In general, there is a small negative, but statistically significant, relationship between the size of the federal deficit in one year and the

  14. Ca isotopes in refractory inclusions

    International Nuclear Information System (INIS)

    Niederer, F.R.; Papanastassiou, D.A.

    1984-01-01

    We report measurements of the absolute isotope abundance of Ca in Ca-Al-rich inclusions from the Allende and Leoville meteorites. Improved high precision measurements are reported also for 46 Ca. We find that nonlinear isotope effects in Ca are extremely rare in these inclusions. The absence of nonlinear effects in Ca, except for the effects in FUN inclusions, is in sharp contrast to the endemic effects in Ti. One fine-grained inclusion shows an excess of 46 Ca of (7 +- 1) per mille, which is consistent with addition of only 46 Ca or of an exotic (*) component with 46 Ca* approx. 48 Ca*. FUN inclusion EK-1-4-1 shows a small 46 Ca excess of (3.3 +- 1.0) per mille; this confirms that the exotic Ca components in EK-1-4-1 were even more deficient in 46 Ca relative to 48 Ca than is the case for normal Ca. The Ca in the Ca-Al-rich inclusions shows mass dependent isotope fractionation effects which have a range from -3.8 to +6.7 per mille per mass unit difference. This range is a factor of 20 wider than the range previously established for bulk meteorites and for terrestrial and lunar samples. Ca and Mg isotope fractionation effects in the Ca-Al-rich inclusions are common and attributed to kinetic isotope effects. (author)

  15. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  16. PRAGMATIC DEFICITS OF ASPERGER SYNDROME

    Directory of Open Access Journals (Sweden)

    Silmy Arizatul Humaira’

    2015-08-01

    Full Text Available Human being is social creature who needs other people to interact with. One of the ways to interact with others is communication with language. However, communication could be a complicated problem for those who were born with developmental disorder called Asperger Syndrome (AS. The communication challenge of Asperger’s is the difficulty using language appropriately for social purposes or known as pragmatic deficits. Many excellent books about autism are published whereas knowledge on pragmatic deficits are still very limited. Thus, it is expected to be a beneficial reference to understand the pragmatic deficits and to create strategies for them to communicate effectively. Therefore, this study aimed at exploring the kinds of pragmatic deficits of an individual with AS. The verbal language profiles of autism purposed by MacDonald (2004 is used to analyzed the data in depth. The descriptive qualitative method is applied to develop a comprehensive understanding about the AS case in Temple Grandin movie.The finding shows that all of the five types of communication deficits are appearing and the dominant of which is unresponsive.

  17. Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4: Calculated dehydrogenation enthalpy, including zero point energy, and the structure of the phonon spectra.

    Science.gov (United States)

    Marashdeh, Ali; Frankcombe, Terry J

    2008-06-21

    The dehydrogenation enthalpies of Ca(AlH(4))(2), CaAlH(5), and CaH(2)+6LiBH(4) have been calculated using density functional theory calculations at the generalized gradient approximation level. Harmonic phonon zero point energy (ZPE) corrections have been included using Parlinski's direct method. The dehydrogenation of Ca(AlH(4))(2) is exothermic, indicating a metastable hydride. Calculations for CaAlH(5) including ZPE effects indicate that it is not stable enough for a hydrogen storage system operating near ambient conditions. The destabilized combination of LiBH(4) with CaH(2) is a promising system after ZPE-corrected enthalpy calculations. The calculations confirm that including ZPE effects in the harmonic approximation for the dehydrogenation of Ca(AlH(4))(2), CaAlH(5), and CaH(2)+6LiBH(4) has a significant effect on the calculated reaction enthalpy. The contribution of ZPE to the dehydrogenation enthalpies of Ca(AlH(4))(2) and CaAlH(5) calculated by the direct method phonon analysis was compared to that calculated by the frozen-phonon method. The crystal structure of CaAlH(5) is presented in the more useful standard setting of P2(1)c symmetry and the phonon density of states of CaAlH(5), significantly different to other common complex metal hydrides, is rationalized.

  18. Trabecular bone deficits among Vietnamese immigrants.

    Science.gov (United States)

    Melton, L J; Marquez, M A; McCready, L K; Achenbach, S J; Riggs, B L; Amin, S; Khosla, S

    2011-05-01

    Compared to white women, lower areal bone mineral density (aBMD) in middle-aged Vietnamese immigrants is due to reduced trabecular volumetric bone mineral density (vBMD), which in turn is associated with greater trabecular separation along with lower estrogen levels. The epidemiology of osteoporosis in Asian populations is still poorly known, but we previously found a deficit in lumbar spine aBMD among postmenopausal Southeast Asian women, compared to white women, that persisted after correction for bone size. This issue was revisited using more sophisticated imaging techniques. Twenty Vietnamese immigrants (age, 44-79 years) were compared to 162 same-aged white women with respect to aBMD at the hip, spine and wrist, vBMD at the hip and spine by quantitative computed tomography and vBMD and bone microstructure at the ultradistal radius by high-resolution pQCT. Bone turnover and sex steroid levels were assessed in a subset (20 Vietnamese and 40 white women). The aBMD was lower at all sites among the Vietnamese women, but femoral neck vBMD did not differ from middle-aged white women. Significant differences in lumbar spine and ultradistal radius vBMD in the Vietnamese immigrants were due to lower trabecular vBMD, which was associated with increased trabecular separation. Bone resorption was elevated and bone formation depressed among the Vietnamese immigrants, although trends were not statistically significant. Serum estradiol was positively associated with trabecular vBMD in the Vietnamese women, but their estrogen levels were dramatically lower compared to white women. Although reported discrepancies in aBMD among Asian women are mainly an artifact of smaller bone size, we identified a specific deficit in the trabecular bone among a sample of Vietnamese immigrants that may be related to low estrogen levels and which needs further study.

  19. LaNiO{sub 3} buffer layers for high critical current density YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} and Tl{sub 2}Ba{sub 2}CaCu{sub 2}O{sub 8{minus}{delta}} films

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, C.M.; Parilla, P.A.; Siegal, M.P.; Ginley, D.S.; Wang, Y.; Blaugher, R.D.; Price, J.C.; Overmyer, D.L.; Venturini, E.L.

    1999-10-01

    We demonstrate high critical current density superconducting films of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) and Tl{sub 2}Ba{sub 2}CaCu{sub 2}O{sub 8{minus}{delta}} (Tl-2212) using LaNiO{sub 3} (LNO) buffer layers. YBCO films grown on an LNO buffer layer have only a slightly lower J{sub c} (5 K, H=0) than films grown directly on a bare LaAlO{sub 3} substrate. YBCO films grown on LNO buffer layers exhibit minor microstructural disorder and enhanced flux pinning. LNO-buffered Tl-2212 samples show large reductions in J{sub c} at all temperatures and fields compared to those grown on bare LaAlO{sub 3}, correlating to both {ital a}-axis grain and nonsuperconducting phase formation. LNO could be a promising buffer layer for both YBCO and Tl-based superconducting films in coated conductor applications. {copyright} {ital 1999 American Institute of Physics.}

  20. Level densities

    International Nuclear Information System (INIS)

    Ignatyuk, A.V.

    1998-01-01

    For any applications of the statistical theory of nuclear reactions it is very important to obtain the parameters of the level density description from the reliable experimental data. The cumulative numbers of low-lying levels and the average spacings between neutron resonances are usually used as such data. The level density parameters fitted to such data are compiled in the RIPL Starter File for the tree models most frequently used in practical calculations: i) For the Gilber-Cameron model the parameters of the Beijing group, based on a rather recent compilations of the neutron resonance and low-lying level densities and included into the beijing-gc.dat file, are chosen as recommended. As alternative versions the parameters provided by other groups are given into the files: jaeri-gc.dat, bombay-gc.dat, obninsk-gc.dat. Additionally the iljinov-gc.dat, and mengoni-gc.dat files include sets of the level density parameters that take into account the damping of shell effects at high energies. ii) For the backed-shifted Fermi gas model the beijing-bs.dat file is selected as the recommended one. Alternative parameters of the Obninsk group are given in the obninsk-bs.dat file and those of Bombay in bombay-bs.dat. iii) For the generalized superfluid model the Obninsk group parameters included into the obninsk-bcs.dat file are chosen as recommended ones and the beijing-bcs.dat file is included as an alternative set of parameters. iv) For the microscopic approach to the level densities the files are: obninsk-micro.for -FORTRAN 77 source for the microscopical statistical level density code developed in Obninsk by Ignatyuk and coworkers, moller-levels.gz - Moeller single-particle level and ground state deformation data base, moller-levels.for -retrieval code for Moeller single-particle level scheme. (author)

  1. Automatic Deficits can lead to executive deficits in ADHD

    Directory of Open Access Journals (Sweden)

    Gabriella Martino

    2017-12-01

    Full Text Available It has been well documented an executive dysfunction in children with Attention Deficit Hyperactivity Disorder (ADHD and with Reading Disorder (RD. The purpose of the present study was to test an alternative hypothesis that deficits in executive functioning within ADHD may be partially due to an impairment of the automatic processing. In addition, since the co-occurrence between ADHD and RD, we tested the hypothesis that the automatic processing may be  a possible common cognitive factor between ADHD and RD. We investigated the automatic processing of selective visual attention through two experiments. 12 children with ADHD, 17 with ADHD+RD and 29 typically developing children, matched for age and gender, performed two tasks: Visual Information Processing Task and Clock Test. As expected, ADHD and ADHD+RD groups differed from the control group in controlled process task, suggesting a deficit in executive functioning. All clinical subjects also exhibited a lower performance in automatic processes, compared to control group. The results of this study suggest that executive deficits within ADHD can be partially due to an impairment of automatic processing.

  2. Density heterogeneity of the cratonic lithosphere

    DEFF Research Database (Denmark)

    Cherepanova, Yulia; Artemieva, Irina

    2015-01-01

    Using free-board modeling, we examine a vertically-averaged mantle density beneath the Archean-Proterozoic Siberian craton in the layer from the Moho down to base of the chemical boundary layer (CBL). Two models are tested: in Model 1 the base of the CBL coincides with the LAB, whereas in Model 2...... the base of the CBL is at a 180 km depth. The uncertainty of density model is density structure of the Siberian lithospheric mantle with a strong...... correlation between mantle density variations and the tectonic setting. Three types of cratonic mantle are recognized from mantle density anomalies. 'Pristine' cratonic regions not sampled by kimberlites have the strongest depletion with density deficit of 1.8-3.0% (and SPT density of 3.29-3.33 t/m3...

  3. Structural, electronic, elastic, and thermodynamic properties of CaSi, Ca2Si, and CaSi2 phases from first-principles calculations

    Science.gov (United States)

    Li, X. D.; Li, K.; Wei, C. H.; Han, W. D.; Zhou, N. G.

    2018-06-01

    The structural, electronic, elastic, and thermodynamic properties of CaSi, Ca2Si, and CaSi2 are systematically investigated by using first-principles calculations method based on density functional theory (DFT). The calculated formation enthalpies and cohesive energies show that CaSi2 possesses the greatest structural stability and CaSi has the strongest alloying ability. The structural stability of the three phases is compared according to electronic structures. Further analysis on electronic structures indicates that the bonding of these phases exhibits the combinations of metallic, covalent, and ionic bonds. The elastic constants are calculated, and the bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and anisotropy factor of polycrystalline materials are deduced. Additionally, the thermodynamic properties were theoretically predicted and discussed.

  4. Attention Deficit Hyperactivity Disorder (ADHD)

    Centers for Disease Control (CDC) Podcasts

    2014-04-10

    This podcast discusses Attention Deficit Hyperactivity Disorder, or ADHD, the most common behavioral disorder in children. Learn about symptoms, risk factors, and treatment.  Created: 4/10/2014 by National Center on Birth Defects and Developmental Disabilities (NCBDDD).   Date Released: 5/7/2014.

  5. Rhythm Deficits in "Tone Deafness"

    Science.gov (United States)

    Foxton, Jessica M.; Nandy, Rachel K.; Griffiths, Timothy D.

    2006-01-01

    It is commonly observed that "tone deaf" individuals are unable to hear the beat of a tune, yet deficits on simple timing tests have not been found. In this study, we investigated rhythm processing in nine individuals with congenital amusia ("tone deafness") and nine controls. Participants were presented with pairs of 5-note sequences, and were…

  6. Utilización del factor de densidad de energía de deformación en el modelo de crecimiento de la grieta en árboles de molinos de caña de azúcar. // Use of the density deformation energy factor in the crack growth pattern of sugar cane mills axles.

    Directory of Open Access Journals (Sweden)

    N. Arzola de la Peña

    2005-05-01

    Full Text Available En el trabajo se aplica el criterio de densidad de energía de deformación en el modelo de crecimiento de la grieta para losárboles de los molinos de caña de azúcar. La utilización de este criterio permite predecir no solamente la razón decrecimiento de las grietas sino también la inclinación que las mismas van experimentando durante su propagación, conrespecto al plano inicial donde surgen. Son modelados los dos tipos de grietas que usualmente ocurren en estos elementos,la grieta semielíptica superficial y la circunferencial. Se demuestra que la grieta circunferencial siempre crece en un planonormal al eje del árbol, mientras que las semielípticas lo harán en un plano algo inclinado en dependencia del predominiode las tensiones tangenciales. La grieta circunferencial resultó ser más crítica que la semielíptica superficial.Palabras claves: Energía de deformación, molinos de caña, propagación de grietas._______________________________________________________________________________Abstract.In this paper the approach of the density deformation energy factor in the crack growth pattern of sugar cane mills axles isapplied. The use of this approach allows predicting not only the rate of cracks growth but also the inclination that the sameones experienced during its propagation, with regard to the initial plane where they arise. The two types of cracks thatusually happens in these elements are modelled, the semielliptical superficial crack and the circumferential. It isdemonstrated that the circumferential crack always grows in a normal plane to the axis of the axle, while the semiellipticalwill make it in a plane something bowed in dependence of the prevalence of the tangential tensions. The circumferentialcrack turned out to be more critical than the semielliptical superficial.Keywords: Energy of deformation, cane mills, crack propagation.

  7. Comparison of montreal cognitive assessment and mini-mental state examination in evaluating cognitive domain deficit following aneurysmal subarachnoid haemorrhage.

    Directory of Open Access Journals (Sweden)

    George Kwok Chu Wong

    Full Text Available Cognitive deficits are common after aneurysmal subarachnoid haemorrhage (aSAH, and clinical evaluation is important for their management. Our hypothesis was that the Montreal Cognitive Assessment (MoCa is superior to the Mini-Mental State Examination (MMSE in screening for cognitive domain deficit in aSAH patients.We carried out a prospective observational and diagnostic accuracy study on Hong Kong aSAH patients aged 21 to 75 years who had been admitted within 96 hours of ictus. The domain-specific neuropsychological assessment battery, the MoCA and MMSE were administered 2-4 weeks and 1 year after ictus. A cognitive domain deficit was defined as a cognitive domain z score <-1.65 (below the fifth percentile. Cognitive impairment was defined as two or more cognitive domain deficits. The study is registered at ClinicalTrials.gov of the US National Institutes of Health (NCT01038193.Both the MoCA and the MMSE were successful in differentiating between patients with and without cognitive domain deficits and cognitive impairment at both assessment periods. At 1 year post-ictus, the MoCA produced higher area under the curve scores for cognitive impairment than the MMSE (MoCA, 0.92; 95% CI, 0.83 to 0.97 versus MMSE, 0.77; 95% CI, 0.66 to 0.83, p = 0.009.Cognitive domain deficits and cognitive impairment in patients with aSAH can be screened with the MoCA in both the subacute and chronic phases.

  8. Neurocognitive impairment in deficit and non-deficit schizophrenia: a meta-analysis.

    Science.gov (United States)

    Bora, E; Binnur Akdede, B; Alptekin, K

    2017-10-01

    Most studies suggested that patients with deficit schizophrenia have more severe impairment compared with patients with non-deficit schizophrenia. However, it is not clear whether deficit and non-deficit schizophrenia are associated with differential neurocognitive profiles. The aim of this meta-analytic review was to compare cognitive performances of deficit and non-deficit patients with each other and with healthy controls. In the current meta-analysis, differences in cognitive abilities between 897 deficit and 1636 non-deficit patients with schizophrenia were examined. Cognitive performances of 899 healthy controls were also compared with 350 patients with deficit and 592 non-deficit schizophrenia. Both deficit (d = 1.04-1.53) and non-deficit (d = 0.68-1.19) schizophrenia were associated with significant deficits in all cognitive domains. Deficit patients underperformed non-deficit patients in all cognitive domains (d = 0.24-0.84) and individual tasks (d = 0.39-0.93). The relationship between deficit syndrome and impairment in olfaction, social cognition, verbal fluency, and speed-based cognitive tasks were relatively stronger. Our findings suggest that there is consistent evidence for a significant relationship between deficit syndrome and more severe cognitive impairment in schizophrenia.

  9. Phase diagram of Se-CaIn4Se7 system

    International Nuclear Information System (INIS)

    Musaeva, R.I.; Aliev, I.I; Ismailova, F.I; Aliev, A.A

    2011-01-01

    Full text: The Se-CaIn 4 Se 7 system has been studied using methods of differential thermal analysis, X-ray diffraction, micro structural analysis, density measurements and its phase diagram has been constructed. It has been established that the section Se-CaIn 4 Se 7 is a quasibinary section of the ternary system Ca-In-Se. At room temperature, on the basis of CaIn 2 Se 4 and Se no solid solution has been found

  10. Perception in attention deficit hyperactivity disorder

    NARCIS (Netherlands)

    Fuermaier, Anselm B.M.; Hüpen, Philippa; De Vries, Stefanie M.; Müller, Morgana; Kok, Francien M.; Koerts, Janneke; Heutink, Joost; Tucha, Lara; Gerlach, Manfred; Tucha, Oliver

    A large body of research demonstrated that individuals with attention deficit hyperactivity disorder (ADHD) suffer from various neuropsychological deficits. In contrast, less is known and only divergent evidence exists on perceptual functions of individuals with ADHD. This is problematic as

  11. Focusing on ADHD - Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    ... September 2014 Print this issue Focusing on ADHD Attention Deficit Hyperactivity Disorder En español Send us your comments ... might be signs of a developmental disorder called attention deficit hyperactivity disorder, or ADHD. ADHD is a common ...

  12. Attention-Deficit Hyperactivity Disorder (ADHD)

    Science.gov (United States)

    ... Tube DysfunctionStrep ThroatAnemiaHyperthyroidismOpioid AddictionDiabetesCroup Home Diseases and Conditions Attention-Deficit Hyperactivity Disorder (ADHD) Condition Attention-Deficit Hyperactivity Disorder ( ...

  13. Adult Attention-Deficit / Hyperactivity Disorder (ADHD)

    Science.gov (United States)

    Adult attention-deficit/hyperactivity disorder (ADHD) Overview Adult attention-deficit/hyperactivity disorder (ADHD) is a mental health disorder that includes a combination of persistent problems, such as difficulty paying attention, ...

  14. Faststats: Attention Deficit Hyperactivity Disorder (ADHD)

    Science.gov (United States)

    ... this? Submit What's this? Submit Button NCHS Home Attention Deficit Hyperactivity Disorder (ADHD)* Recommend on Facebook Tweet Share Compartir Data ... attention deficit disorder (ADD)” is used rather than “attention deficit hyperactivity disorder (ADHD)” in some data sources. More data Tables ...

  15. Pragmatic Communication Deficits in Children with Epilepsy

    Science.gov (United States)

    Broeders, Mark; Geurts, Hilde; Jennekens-Schinkel, Aag

    2010-01-01

    Background: Various psychiatric and neurological disorders including epilepsy have been associated with language deficits. Pragmatic language deficits, however, have seldom been the focus of earlier studies in children with epilepsy. Moreover, it is unknown whether these pragmatic deficits are related to general intellectual functioning. Both…

  16. BDNF (brain-derived neurotrophic factor) serum levels in schizophrenic patients with cognitive deficits

    Science.gov (United States)

    Utami, N.; Effendy, E.; Amin, M. M.

    2018-03-01

    Schizophrenia is a complex neurodevelopmental disorder with cognitive impairment as the main part. BDNF regulates aspects of developmental plasticity in the brain and is involved in cognitive function. Cognitive functions include capabilities such as attention, executive functioning, assessing, monitoring and evaluating. The aim of the study was to know the BDNF levels in schizophrenic patients with cognitive deficits. The study was held in October 2016 - March 2017, and was the first in Indonesia, especially in North Sumatra. The study was approved by the medical ethics committee of the University of North Sumatera. The study is descriptive based on a retrospective method with cross-sectional approach. The subject is 40 male schizophrenia. Cognitive deficits were assessed by MoCA-Ina. BDNF serum levels were analyzed using the quantitative sandwich enzyme immunoassay. The average MoCA-Ina score is 21.03±5.21. This suggests that there is a cognitive function deficit in schizophrenic patients. The mean serum BDNF level was 26629±6762. MoCA-Ina scores in schizophrenic patients <26 who experienced a deficit of 77.5% and serum BDNF levels with normal values ranging from 6.186 to 42.580pg/ml.

  17. Attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Meek, D C

    1990-09-01

    The attention-deficit hyperactivity disorder is a common chronic disorder of childhood. No precise definition or approach to treatment is universally accepted; however, an extensive literature exists on which to base a rational approach to management. Symptomatic treatment with stimulant medication in selected patients is effective and safe, but not curative. Successful outcome depends on multimodality therapy, involving parents, teachers, and other professionals. Associated conditions, including learning disorders and emotional disturbance, must be identified and dealt with.

  18. Can we predict cognitive deficits based on cognitive complaints?

    Directory of Open Access Journals (Sweden)

    Ewa Małgorzata Szepietowska

    2017-03-01

    Full Text Available Objective: The aim of the study was to determine whether the intensity of cognitive complaints can, in conjunction with other selected variables, predict the general level of cognitive functions evaluated with the Montreal Cognitive Assessment (MoCA test. Current reports do not show clear conclusions on this subject. Some data indicate that cognitive complaints have a predictive value for low scores in standardised tasks, suggesting cognitive dysfunction (e.g. mild cognitive impairment. Other data, however, do not support the predictive role of complaints, and show no relationship to exist between the complaints and the results of cognitive tests. Material and methods: The study included 118 adults (58 women and 60 men. We used the MoCA test, a self-report questionnaire assessing the intensity of cognitive complaints (Patient-Reported Outcomes in Cognitive Impairment – PROCOG and Dysexecutive Questionnaire/Self – DEX-S, and selected subtests of the Wechsler Adult Intelligence Scale-Revised (WAIS-R PL. On the basis of the results from the MoCA test, two separate groups were created, one comprising respondents with lower results, and one – those who obtained scores indicating a normal level of cognitive function. We compared these groups according to the severity of the complaints and the results obtained with the other methods. Logistic regression analysis was performed taking into account the independent variables (gender, age, result in PROCOG, DEX-S, and neurological condition and the dependent variable (dichotomized result in MoCA. Results: Groups with different levels of performance in MoCA differed in regards of some cognitive abilities and the severity of complaints related to semantic memory, anxiety associated with a sense of deficit and loss of skills, but provided similar self-assessments regarding the efficiency of episodic memory, long-term memory, social skills and executive functions. The severity of complaints does not allow

  19. Physiological and Pathological Roles of CaMKII-PP1 Signaling in the Brain

    Directory of Open Access Journals (Sweden)

    Norifumi Shioda

    2017-12-01

    Full Text Available Ca2+/calmodulin (CaM-dependent protein kinase II (CaMKII, a multifunctional serine (Ser/threonine (Thr protein kinase, regulates diverse activities related to Ca2+-mediated neuronal plasticity in the brain, including synaptic activity and gene expression. Among its regulators, protein phosphatase-1 (PP1, a Ser/Thr phosphatase, appears to be critical in controlling CaMKII-dependent neuronal signaling. In postsynaptic densities (PSDs, CaMKII is required for hippocampal long-term potentiation (LTP, a cellular process correlated with learning and memory. In response to Ca2+ elevation during hippocampal LTP induction, CaMKIIα, an isoform that translocates from the cytosol to PSDs, is activated through autophosphorylation at Thr286, generating autonomous kinase activity and a prolonged Ca2+/CaM-bound state. Moreover, PP1 inhibition enhances Thr286 autophosphorylation of CaMKIIα during LTP induction. By contrast, CaMKII nuclear import is regulated by Ser332 phosphorylation state. CaMKIIδ3, a nuclear isoform, is dephosphorylated at Ser332 by PP1, promoting its nuclear translocation, where it regulates transcription. In this review, we summarize physio-pathological roles of CaMKII/PP1 signaling in neurons. CaMKII and PP1 crosstalk and regulation of gene expression is important for neuronal plasticity as well as survival and/or differentiation.

  20. The extent of intrauterine growth restriction determines the severity of cerebral injury and neurobehavioural deficits in rodents.

    Science.gov (United States)

    Ruff, Crystal A; Faulkner, Stuart D; Rumajogee, Prakasham; Beldick, Stephanie; Foltz, Warren; Corrigan, Jennifer; Basilious, Alfred; Jiang, Shangjun; Thiyagalingam, Shanojan; Yager, Jerome Y; Fehlings, Michael G

    2017-01-01

    Cerebral Palsy (CP) is the most common physical pediatric neurodevelopmental disorder and spastic diplegic injury is its most frequent subtype. CP results in substantial neuromotor and cognitive impairments that have significant socioeconomic impact. Despite this, its underlying pathophysiological mechanisms and etiology remain incompletely understood. Furthermore, there is a need for clinically relevant injury models, which a) reflect the heterogeneity of the condition and b) can be used to evaluate new translational therapies. To address these key knowledge gaps, we characterized a chronic placental insufficiency (PI) model, using bilateral uterine artery ligation (BUAL) of dams. This injury model results in intrauterine growth restriction (IUGR) in pups, and animals recapitulate the human phenotype both in terms of neurobehavioural and anatomical deficits. Effects of BUAL were studied using luxol fast blue (LFB)/hematoxylin & eosin (H&E) staining, immunohistochemistry, quantitative Magnetic Resonance Imaging (MRI), and Catwalk neurobehavioural tests. Neuroanatomical analysis revealed regional ventricular enlargement and corpus callosum thinning in IUGR animals, which was correlated with the extent of growth restriction. Olig2 staining revealed reductions in oligodendrocyte density in white and grey matter structures, including the corpus callosum, optic chiasm, and nucleus accumbens. The caudate nucleus, along with other brain structures such as the optic chiasm, internal capsule, septofimbrial and lateral septal nuclei, exhibited reduced size in animals with IUGR. The size of the pretectal nucleus was reduced only in moderately injured animals. MAG/NF200 staining demonstrated reduced myelination and axonal counts in the corpus callosum of IUGR animals. NeuN staining revealed changes in neuronal density in the hippocampus and in the thickness of hippocampal CA2 and CA3 regions. Diffusion weighted imaging (DWI) revealed regional white and grey matter changes at 3

  1. The extent of intrauterine growth restriction determines the severity of cerebral injury and neurobehavioural deficits in rodents.

    Directory of Open Access Journals (Sweden)

    Crystal A Ruff

    Full Text Available Cerebral Palsy (CP is the most common physical pediatric neurodevelopmental disorder and spastic diplegic injury is its most frequent subtype. CP results in substantial neuromotor and cognitive impairments that have significant socioeconomic impact. Despite this, its underlying pathophysiological mechanisms and etiology remain incompletely understood. Furthermore, there is a need for clinically relevant injury models, which a reflect the heterogeneity of the condition and b can be used to evaluate new translational therapies. To address these key knowledge gaps, we characterized a chronic placental insufficiency (PI model, using bilateral uterine artery ligation (BUAL of dams. This injury model results in intrauterine growth restriction (IUGR in pups, and animals recapitulate the human phenotype both in terms of neurobehavioural and anatomical deficits.Effects of BUAL were studied using luxol fast blue (LFB/hematoxylin & eosin (H&E staining, immunohistochemistry, quantitative Magnetic Resonance Imaging (MRI, and Catwalk neurobehavioural tests.Neuroanatomical analysis revealed regional ventricular enlargement and corpus callosum thinning in IUGR animals, which was correlated with the extent of growth restriction. Olig2 staining revealed reductions in oligodendrocyte density in white and grey matter structures, including the corpus callosum, optic chiasm, and nucleus accumbens. The caudate nucleus, along with other brain structures such as the optic chiasm, internal capsule, septofimbrial and lateral septal nuclei, exhibited reduced size in animals with IUGR. The size of the pretectal nucleus was reduced only in moderately injured animals. MAG/NF200 staining demonstrated reduced myelination and axonal counts in the corpus callosum of IUGR animals. NeuN staining revealed changes in neuronal density in the hippocampus and in the thickness of hippocampal CA2 and CA3 regions. Diffusion weighted imaging (DWI revealed regional white and grey matter

  2. Association between the attention deficits and delinquency

    Directory of Open Access Journals (Sweden)

    Robert Opora

    2011-12-01

    Full Text Available In the society we can find a lot of prejudices concerning AD/HD. The article contains facts and evidence based on research presenting that the delinquency is very often a distant complication of attention deficits but it doesn’t mean that a child with attention deficits has to be delinquent. The article describes the association between the attention deficits and delinquency. There are presented some risk factors coming from the attention deficits and protective factors which let the child follow the social norms. The research was based on 108 delinquent juveniles staying under the probation supervision. The purpose of the research was to evaluate the frequency of the attention deficits among delinquent juveniles staying under supervision. The research findings concern also the association between the attention deficit and external behavioural disorders. In the summary several conditions are described which are important to protect children with attention deficit from delinquency.

  3. Density dependent hadron field theory

    International Nuclear Information System (INIS)

    Fuchs, C.; Lenske, H.; Wolter, H.H.

    1995-01-01

    A fully covariant approach to a density dependent hadron field theory is presented. The relation between in-medium NN interactions and field-theoretical meson-nucleon vertices is discussed. The medium dependence of nuclear interactions is described by a functional dependence of the meson-nucleon vertices on the baryon field operators. As a consequence, the Euler-Lagrange equations lead to baryon rearrangement self-energies which are not obtained when only a parametric dependence of the vertices on the density is assumed. It is shown that the approach is energy-momentum conserving and thermodynamically consistent. Solutions of the field equations are studied in the mean-field approximation. Descriptions of the medium dependence in terms of the baryon scalar and vector density are investigated. Applications to infinite nuclear matter and finite nuclei are discussed. Density dependent coupling constants obtained from Dirac-Brueckner calculations with the Bonn NN potentials are used. Results from Hartree calculations for energy spectra, binding energies, and charge density distributions of 16 O, 40,48 Ca, and 208 Pb are presented. Comparisons to data strongly support the importance of rearrangement in a relativistic density dependent field theory. Most striking is the simultaneous improvement of charge radii, charge densities, and binding energies. The results indicate the appearance of a new ''Coester line'' in the nuclear matter equation of state

  4. Ca 125 and Ca 19-9: two cancer-associated sialylsaccharide antigens on a mucus glycoprotein from human milk.

    Science.gov (United States)

    Hanisch, F G; Uhlenbruck, G; Dienst, C; Stottrop, M; Hippauf, E

    1985-06-03

    The cancer-associated antigens Ca 125 and Ca 19-9 were demonstrated by radioimmunoassay to form structural units of a mucus glycoprotein in human milk taken from healthy women four days after parturition. The glycoprotein precipitated with the casein fraction at pH 4.6 and was completely absent in the whey as judged from Ca 19-9 assay. It could be effectively enriched by phenol-saline extraction from soluble milk proteins and further purified by gel filtration on Sephacryl S300 and Sephacryl S400. The active component with a bouyant density of 1.41 g/ml in isopycnic density gradient centrifugation (CsCl) shared common physico-chemical and chemical characteristics of mucus glycoproteins. Carbohydrates representing about 68% by weight were conjugated to protein by alkali-labile linkages, exclusively and were essentially free of D-mannose. Activities of Ca 125 and Ca 19-9 were both destroyed by treatment with periodate, mild alkali or neuraminidase suggesting the antigens are sialylated saccharides bound to protein by alkali-labile linkages. The fraction of monosialylated saccharide alditols isolated after reductive beta-elimination from the mucus glycoprotein was shown to inhibit monoclonal antibodies anti-(Ca 125) and anti-(Ca 19-9) in radioimmunoassay.

  5. A role for CA3 in social recognition memory.

    Science.gov (United States)

    Chiang, Ming-Ching; Huang, Arthur J Y; Wintzer, Marie E; Ohshima, Toshio; McHugh, Thomas J

    2018-02-02

    Social recognition memory is crucial for survival across species, underlying the need to correctly identify conspecifics, mates and potential enemies. In humans the hippocampus is engaged in social and episodic memory, however the circuit mechanisms of social memory in rodent models has only recently come under scrutiny. Work in mice has established that the dorsal CA2 and ventral CA1 regions play critical roles, however a more comprehensive comparative analyses of the circuits and mechanisms required has not been reported. Here we employ conditional genetics to examine the differential contributions of the hippocampal subfields to social memory. We find that the deletion of NMDA receptor subunit 1 gene (NR1), which abolishes NMDA receptor synaptic plasticity, in CA3 pyramidal cells led to deficits in social memory; however, mice lacking the same gene in DG granule cells performed indistinguishable from controls. Further, we use conditional pharmacogenetic inhibition to demonstrate that activity in ventral, but not dorsal, CA3 is necessary for the encoding of a social memory. These findings demonstrated CA3 pyramidal cell plasticity and transmission contribute to the encoding of social stimuli and help further identify the distinct circuits underlying the role of the hippocampus in social memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Solubility of calcium in CaO-CaCl2

    International Nuclear Information System (INIS)

    Perry, G.S.; Shaw, S.J.

    1991-06-01

    The Direct Oxide Reduction (DOR) process is well established as a process to produce plutonium metal from plutonium dioxide by reaction with calcium. Calcium chloride is added to dissolve the calcium oxide produced, allowing the metal to coalesce into a button. Since calcium metal melts at 840 0 C and DOR can take place successfully below this temperature, it is likely calcium dissolved in calcium chloride reacts with the plutonium dioxide. The solubility of calcium in calcium chloride is reasonably well established but the effect of the CaO formed during the DOR process on the solubility of calcium has not been previously determined. For this reason the solubility of calcium in CaCl 2 -CaO melts at 800 o C has been studied. The solubility decreases from 2.7 mol % in CaCl 2 to 0.4 mol % in 9 mol % CaO-CaCl 2 . (author)

  7. Administration of the TrkB receptor agonist 7,8-dihydroxyflavone prevents traumatic stress-induced spatial memory deficits and changes in synaptic plasticity.

    Science.gov (United States)

    Sanz-García, Ancor; Knafo, Shira; Pereda-Pérez, Inmaculada; Esteban, José A; Venero, César; Armario, Antonio

    2016-09-01

    Post-traumatic stress disorder (PTSD) occurs after exposure to traumatic situations and it is characterized by cognitive deficits that include impaired explicit memory. The neurobiological bases of such PTSD-associated memory alterations are yet to be elucidated and no satisfactory treatment for them exists. To address this issue, we first studied whether a single exposure of young adult rats (60 days) to immobilization on boards (IMO), a putative model of PTSD, produces long-term behavioral effects (2-8 days) similar to those found in PTSD patients. Subsequently, we investigated whether the administration of the TrkB agonist 7,8-dihydroxyflavone (DHF) 8 h after stress (therapeutic window) ameliorated the PTSD-like effect of IMO and the associated changes in synaptic plasticity. A single IMO exposure induced a spatial memory impairment similar to that found in other animal models of PTSD or in PTSD patients. IMO also increased spine density and long-term potentiation (LTP) in the CA3-CA1 pathway. Significantly, DHF reverted both spatial memory impairment and the increase in LTP, while it produced no effect in the controls. These data provide novel insights into the possible neurobiological substrate for explicit memory impairment in PTSD patients, supporting the idea that the activation of the BDNF/TrkB pathway fulfils a protective role after severe stress. Administration of DHF in the aftermath of a traumatic experience might be relevant to prevent its long-term consequences. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Ablation of Ca(V)2.1 voltage-gated Ca²⁺ channels in mouse forebrain generates multiple cognitive impairments.

    Science.gov (United States)

    Mallmann, Robert Theodor; Elgueta, Claudio; Sleman, Faten; Castonguay, Jan; Wilmes, Thomas; van den Maagdenberg, Arn; Klugbauer, Norbert

    2013-01-01

    Voltage-gated Ca(V)2.1 (P/Q-type) Ca²⁺ channels located at the presynaptic membrane are known to control a multitude of Ca²⁺-dependent cellular processes such as neurotransmitter release and synaptic plasticity. Our knowledge about their contributions to complex cognitive functions, however, is restricted by the limited adequacy of existing transgenic Ca(V)2.1 mouse models. Global Ca(V)2.1 knock-out mice lacking the α1 subunit Cacna1a gene product exhibit early postnatal lethality which makes them unsuitable to analyse the relevance of Ca(V)2.1 Ca²⁺ channels for complex behaviour in adult mice. Consequently we established a forebrain specific Ca(V)2.1 knock-out model by crossing mice with a floxed Cacna1a gene with mice expressing Cre-recombinase under the control of the NEX promoter. This novel mouse model enabled us to investigate the contribution of Ca(V)2.1 to complex cognitive functions, particularly learning and memory. Electrophysiological analysis allowed us to test the specificity of our conditional knock-out model and revealed an impaired synaptic transmission at hippocampal glutamatergic synapses. At the behavioural level, the forebrain-specific Ca(V)2.1 knock-out resulted in deficits in spatial learning and reference memory, reduced recognition memory, increased exploratory behaviour and a strong attenuation of circadian rhythmicity. In summary, we present a novel conditional Ca(V)2.1 knock-out model that is most suitable for analysing the in vivo functions of Ca(V)2.1 in the adult murine forebrain.

  9. Ablation of CaV2.1 Voltage-Gated Ca2+ Channels in Mouse Forebrain Generates Multiple Cognitive Impairments

    Science.gov (United States)

    Mallmann, Robert Theodor; Elgueta, Claudio; Sleman, Faten; Castonguay, Jan; Wilmes, Thomas; van den Maagdenberg, Arn; Klugbauer, Norbert

    2013-01-01

    Voltage-gated CaV2.1 (P/Q-type) Ca2+ channels located at the presynaptic membrane are known to control a multitude of Ca2+-dependent cellular processes such as neurotransmitter release and synaptic plasticity. Our knowledge about their contributions to complex cognitive functions, however, is restricted by the limited adequacy of existing transgenic CaV2.1 mouse models. Global CaV2.1 knock-out mice lacking the α1 subunit Cacna1a gene product exhibit early postnatal lethality which makes them unsuitable to analyse the relevance of CaV2.1 Ca2+ channels for complex behaviour in adult mice. Consequently we established a forebrain specific CaV2.1 knock-out model by crossing mice with a floxed Cacna1a gene with mice expressing Cre-recombinase under the control of the NEX promoter. This novel mouse model enabled us to investigate the contribution of CaV2.1 to complex cognitive functions, particularly learning and memory. Electrophysiological analysis allowed us to test the specificity of our conditional knock-out model and revealed an impaired synaptic transmission at hippocampal glutamatergic synapses. At the behavioural level, the forebrain-specific CaV2.1 knock-out resulted in deficits in spatial learning and reference memory, reduced recognition memory, increased exploratory behaviour and a strong attenuation of circadian rhythmicity. In summary, we present a novel conditional CaV2.1 knock-out model that is most suitable for analysing the in vivo functions of CaV2.1 in the adult murine forebrain. PMID:24205277

  10. Ablation of Ca(V2.1 voltage-gated Ca²⁺ channels in mouse forebrain generates multiple cognitive impairments.

    Directory of Open Access Journals (Sweden)

    Robert Theodor Mallmann

    Full Text Available Voltage-gated Ca(V2.1 (P/Q-type Ca²⁺ channels located at the presynaptic membrane are known to control a multitude of Ca²⁺-dependent cellular processes such as neurotransmitter release and synaptic plasticity. Our knowledge about their contributions to complex cognitive functions, however, is restricted by the limited adequacy of existing transgenic Ca(V2.1 mouse models. Global Ca(V2.1 knock-out mice lacking the α1 subunit Cacna1a gene product exhibit early postnatal lethality which makes them unsuitable to analyse the relevance of Ca(V2.1 Ca²⁺ channels for complex behaviour in adult mice. Consequently we established a forebrain specific Ca(V2.1 knock-out model by crossing mice with a floxed Cacna1a gene with mice expressing Cre-recombinase under the control of the NEX promoter. This novel mouse model enabled us to investigate the contribution of Ca(V2.1 to complex cognitive functions, particularly learning and memory. Electrophysiological analysis allowed us to test the specificity of our conditional knock-out model and revealed an impaired synaptic transmission at hippocampal glutamatergic synapses. At the behavioural level, the forebrain-specific Ca(V2.1 knock-out resulted in deficits in spatial learning and reference memory, reduced recognition memory, increased exploratory behaviour and a strong attenuation of circadian rhythmicity. In summary, we present a novel conditional Ca(V2.1 knock-out model that is most suitable for analysing the in vivo functions of Ca(V2.1 in the adult murine forebrain.

  11. Budget Deficits Effects on Economic Growth

    Directory of Open Access Journals (Sweden)

    L.C.Risti

    2013-06-01

    Full Text Available The budget deficit can not be analyzed autarchically, as it affects all the macroeconomic processes and, is itself influenced by all other macroeconomic indicators. Most analyses and studies on public finance and budget balance measure the impact that budgetary deficits accumulation has on economy. Therefore, the present paper aims at following and analyzing the mutual impact between budget deficit and another economic macro indicator, namely the economic growth.

  12. Neurocognitive Deficits in Borderline Personality Disorder

    DEFF Research Database (Denmark)

    Thomsen, Marianne Skovgaard; Ruocco, Anthony C; Carcone, Dean

    2017-01-01

    completed a comprehensive battery of neurocognitive tests, a retrospective questionnaire on early life trauma and a dimensional measure of personality psychopathology. Patients with BPD primarily showed deficits in verbal comprehension, sustained visual attention, working memory and processing speed...... suggest that patients with BPD display deficits mainly in higher-order thinking abilities that may be exacerbated by PTSD and substantial early life trauma. Potential relationships between neurocognitive deficits and dimensions of personality psychopathology in BPD need further examination....

  13. Chronic Methamphetamine Exposure Produces a Delayed, Long-Lasting Memory Deficit

    OpenAIRE

    North, Ashley; Swant, Jarod; Salvatore, Michael F.; Gamble-George, Joyonna; Prins, Petra; Butler, Brittany; Mittal, Mukul K.; Heltsley, Rebecca; Clark, John T.; Khoshbouei, Habibeh

    2013-01-01

    Methamphetamine (METH) is a highly addictive and neurotoxic psychostimulant. Its use in humans is often associated with neurocognitive impairment. Whether this is due to long-term deficits in short-term memory and/or hippocampal plasticity remains unclear. Recently, we reported that METH increases baseline synaptic transmission and reduces LTP in an ex vivo preparation of the hippocampal CA1 region from young mice. In the current study, we tested the hypothesis that a repeated neurotoxic regi...

  14. Accessing the nuclear symmetry energy in Ca+Ca collisions

    Directory of Open Access Journals (Sweden)

    Chbihi A.

    2012-07-01

    Full Text Available The status of the analysis of the INDRA-VAMOS experiement performed at GANIL, using the reactions 40,48Ca+40,48Ca reactions at 35AMeV, are presented. Isotopic distributions of fragments produced in multifragmentation events provide information on the importance of the surface term contribution in the symmetry energy by comparison to AMD predictions.

  15. A close association of RyRs with highly dense clusters of Ca2+-activated Cl- channels underlies the activation of STICs by Ca2+ sparks in mouse airway smooth muscle.

    Science.gov (United States)

    Bao, Rongfeng; Lifshitz, Lawrence M; Tuft, Richard A; Bellvé, Karl; Fogarty, Kevin E; ZhuGe, Ronghua

    2008-07-01

    RyRs and Cl((Ca)) channels in Ca(2+) spark sites localize near to each other, and, moreover, Cl((Ca)) channels concentrate in an area with a radius of approximately 600 nm, where their density reaches as high as 300 channels/microm(2). This model reveals that Cl((Ca)) channels are tightly controlled by Ca(2+) sparks via local Ca(2+) signaling.

  16. Chemical hardness and density functional theory

    Indian Academy of Sciences (India)

    Unknown

    RALPH G PEARSON. Chemistry Department, University of California, Santa Barbara, CA 93106, USA. Abstract. The concept of chemical hardness is reviewed from a personal point of view. Keywords. Hardness; softness; hard & soft acids bases (HSAB); principle of maximum hardness. (PMH) density functional theory (DFT) ...

  17. The deficit of current account balances and budgetary deficit in countries in transition

    OpenAIRE

    Sandra Krtalic; Ines Kersan

    1998-01-01

    In restructuring process of their own economies, countries in transition deal with many common problems. One of the problems that transition brought to those countries is deficit in current account, as well as budget deficit. Deficits represent limit to a healthy and fast economic development and progress. Balance in balance of payments, as well as balanced budget are components of macroeconomic system. The authors will give an review of activities on deficits in countries in transition, and ...

  18. Thermodynamic, electronic, and magnetic properties of intrinsic vacancy defects in antiperovskite Ca3SnO

    Science.gov (United States)

    Batool, Javaria; Alay-e-Abbas, Syed Muhammad; Amin, Nasir

    2018-04-01

    The density functional theory based total energy calculations are performed to examine the effect of charge neutral and fully charged intrinsic vacancy defects on the thermodynamic, electronic, and magnetic properties of Ca3SnO antiperovskite. The chemical stability of Ca3SnO is evaluated with respect to binary compounds CaO, CaSn, and Ca2Sn, and the limits of atomic chemical potentials of Ca, Sn, and O atoms for stable synthesis of Ca3SnO are determined within the generalized gradient approximation parametrization scheme. The electronic properties of the pristine and the non-stoichiometric forms of this compound have been explored and the influence of isolated intrinsic vacancy defects (Ca, Sn, and O) on the structural, bonding, and electronic properties of non-stoichiometric Ca3SnO are analyzed. We also predict the possibility of achieving stable ferromagnetism in non-stoichiometric Ca3SnO by means of charge neutral tin vacancies. From the calculated total energies and the valid ranges of atomic chemical potentials, the formation energetics of intrinsic vacancy defects in Ca3SnO are evaluated for various growth conditions. Our results indicate that the fully charged calcium vacancies are thermodynamically stable under the permissible Sn-rich condition of stable synthesis of Ca3SnO, while tin and oxygen vacancies are found to be stable under the extreme Ca-rich condition.

  19. Shock Compression Response of Calcium Fluoride (CaF2)

    Science.gov (United States)

    Root, Seth

    2017-06-01

    The fluorite crystal structure is a textbook lattice that is observed for many systems, such as CaF2, Mg2 Si, and CeO2. Specifically, CaF2 is a useful material for studying the fluorite system because it is readily available as a single crystal. Under static compression, CaF2 is known to have at least three solid phases: fluorite, cotunnite, and a Ni2 In phase. Along the Hugoniot CaF2 undergoes a fluorite to cotunnite phase transition, however, at higher shock pressures it is unknown whether CaF2 undergoes another solid phase transition or melts directly from the cotunnite phase. In this work, we conducted planar shock compression experiments on CaF2 using Sandia's Z-machine and a two-stage light gun up to 900 GPa. In addition, we use density functional theory (DFT) based quantum molecular dynamics (QMD) simulations to provide insight into the CaF2 state along the Hugoniot. In collaboration with: Michael Desjarlais, Ray Lemke, Patricia Kalita, Scott Alexander, Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL850.

  20. Water deficit stress effects on corn (Zea mays, L.) root: shoot ratio

    Science.gov (United States)

    A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation...

  1. Trivial topological phase of CaAgP and the topological nodal-line transition in CaAg (P1 -xA sx)

    Science.gov (United States)

    Xu, N.; Qian, Y. T.; Wu, Q. S.; Autès, G.; Matt, C. E.; Lv, B. Q.; Yao, M. Y.; Strocov, V. N.; Pomjakushina, E.; Conder, K.; Plumb, N. C.; Radovic, M.; Yazyev, O. V.; Qian, T.; Ding, H.; Mesot, J.; Shi, M.

    2018-04-01

    By performing angle-resolved photoemission spectroscopy and first-principles calculations, we address the topological phase of CaAgP and investigate the topological phase transition in CaAg (P1 -xA sx) . We reveal that in CaAgP, the bulk band gap and surface states with a large bandwidth are topologically trivial, in agreement with hybrid density functional theory calculations. The calculations also indicate that application of "negative" hydrostatic pressure can transform trivial semiconducting CaAgP into an ideal topological nodal-line semimetal phase. The topological transition can be realized by partial isovalent P/As substitution at x =0.38 .

  2. Measuring Working Memory Deficits in Aphasia

    Science.gov (United States)

    Mayer, Jamie F.; Murray, Laura L.

    2012-01-01

    Purpose: Many adults with aphasia demonstrate concomitant deficits in working memory (WM), but such deficits are difficult to quantify because of a lack of validated measures as well as the complex interdependence between language and WM. We examined the feasibility, reliability, and internal consistency of an "n"-back task for…

  3. Traumatic brain injury and olfactory deficits

    DEFF Research Database (Denmark)

    Fortin, Audrey; Lefebvre, Mathilde Beaulieu; Ptito, Maurice

    2010-01-01

    . Between 40-44% of the patients showing olfactory impairments were not aware of their deficit. CONCLUSIONS: Since a significant proportion of the patients showing olfactory impairments were not aware of their deficit, it is recommended than clinicians systematically evaluate olfactory functions using...

  4. Neurologic deficit after resection of the sacrum.

    Science.gov (United States)

    Biagini, R; Ruggieri, P; Mercuri, M; Capanna, R; Briccoli, A; Perin, S; Orsini, U; Demitri, S; Arlecchini, S

    1997-01-01

    The authors describe neurologic deficit (sensory, motor, and sphincteral) resulting from sacrifice of the sacral nerve roots removed during resection of the sacrum. The anatomical and functional bases of sphincteral continence and the amount of neurologic deficit are discussed based on level of sacral resection. A large review of the literature on the subject is reported and discussed. The authors emphasize how the neurophysiological bases of sphincteral continence (rectum and bladder) and of sexual ability are still not well known, and how the literature reveals disagreement on the subject. A score system is proposed to evaluate neurologic deficit. The clinical model of neurologic deficit caused by resection of the sacrum may be extended to an evaluation of post-traumatic deficit.

  5. In vitro degradation and cytotoxicity of Mg/Ca composites produced by powder metallurgy.

    Science.gov (United States)

    Zheng, Y F; Gu, X N; Xi, Y L; Chai, D L

    2010-05-01

    Mg/Ca (1 wt.%, 5 wt.%, 10 wt.% Ca) composites were prepared from pure magnesium and calcium powders using the powder metallurgy method, aiming to enlarge the addition of Ca content without the formation of Mg(2)Ca. The microstructures, mechanical properties and cytotoxicities of Mg/Ca composite samples were investigated. The corrosion of Mg/Ca composites in Dulbecco's modified Eagle's medium (DMEM) for various immersion intervals was studied by electrochemical impedance spectroscopy measurements and environmental scanning electron microscope, with the concentrations of released Mg and Ca ions in DMEM for various immersion time intervals being measured. It was shown that the main constitutional phases were Mg and Ca, which were uniformly distributed in the Mg matrix. The ultimate tensile strength (UTS) and elongation of experimental composites decreased with increasing Ca content, and the UTS of Mg/1Ca composite was comparable with that of as-extruded Mg-1Ca alloy. The corrosion potential increased with increasing Ca content, whereas the current density and the impedance decreased. It was found that the protective surface film formed quickly at the initial immersion stage. With increasing immersion time, the surface film became compact, and the corrosion rate of Mg/Ca composites slowed down. The surface film consisted mainly of CaCO(3), MgCO(3)x3H(2)O, HA and Mg(OH)(2) after 72 h immersion in DMEM. Mg/1Ca and Mg/5Ca composite extracts had no significant toxicity (p>0.05) to L-929 cells, whereas Mg/10Ca composite extract induced approximately 40% reduced cell viability. Copyright (c) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  6. The site of net absorption of Ca from the intestinal tract of growing pigs and effect of phytic acid, Ca level and Ca source on Ca digestibility.

    Science.gov (United States)

    González-Vega, J Caroline; Walk, Carrie L; Liu, Yanhong; Stein, Hans H

    2014-01-01

    An experiment was conducted to test the hypothesis that the standardised digestibility of Ca in calcium carbonate and Lithothamnium calcareum Ca is not different regardless of the level of dietary Ca, and that phytic acid affects the digestibility of Ca in these two ingredients to the same degree. The objectives were to determine where in the intestinal tract Ca absorption takes place and if there are measurable quantities of basal endogenous Ca fluxes in the stomach, small intestine or large intestine. Diets contained calcium carbonate or L. calcareum Ca as the sole source of Ca, 0% or 1% phytic acid and 0.4% or 0.8% Ca. A Ca-free diet was also formulated and used to measure endogenous fluxes and losses of Ca. Nine growing pigs (initial body weight 23.8 ± 1.3 kg) were cannulated in the duodenum and in the distal ileum, and faecal, ileal and duodenal samples were collected. Duodenal endogenous fluxes of Ca were greater (p calcareum Ca diets, but that was not the case if calcium carbonate was the source of Ca (interaction, p calcareum Ca was greater (p calcareum Ca. In conclusion, under the conditions of this experiment, standardised digestibility of Ca is not affected by the level of phytic acid, but may be affected by dietary Ca level depending on the Ca source. Calcium from calcium carbonate is mostly absorbed before the duodenum, but Ca from L. calcareum Ca is mostly absorbed in the jejunum and ileum.

  7. Prenatal phencyclidine treatment induces behavioral deficits through impairment of GABAergic interneurons in the prefrontal cortex.

    Science.gov (United States)

    Toriumi, Kazuya; Oki, Mika; Muto, Eriko; Tanaka, Junko; Mouri, Akihiro; Mamiya, Takayoshi; Kim, Hyoung-Chun; Nabeshima, Toshitaka

    2016-06-01

    We previously reported that prenatal treatment with phencyclidine (PCP) induces glutamatergic dysfunction in the prefrontal cortex (PFC), leading to schizophrenia-like behavioral deficits in adult mice. However, little is known about the prenatal effect of PCP treatment on other types of neurons. We focused on γ-aminobutyric acid (GABA)-ergic interneurons and evaluated the effect of prenatal PCP exposure on the neurodevelopment of GABAergic interneurons in the PFC. PCP was administered at the dose of 10 mg/kg/day to pregnant dams from embryonic day 6.5 to 18.5. After the pups were reared to adult, we analyzed their GABAergic system in the PFC using immunohistological, biochemical, and behavioral analyses in adulthood. The prenatal PCP treatment decreased the density of parvalbumin-positive cells and reduced the expression level of glutamic acid decarboxylase 67 (GAD67) and GABA content of the PFC in adults. Additionally, prenatal PCP treatment induced behavioral deficits in adult mice, such as hypersensitivity to PCP and prepulse inhibition (PPI) deficits. These behavioral deficits were ameliorated by pretreatment with the GABAB receptor agonist baclofen. Furthermore, the density of c-Fos-positive cells was decreased after the PPI test in the PFC of mice treated with PCP prenatally, and this effect was ameliorated by pretreatment with baclofen. These findings suggest that prenatal treatment with PCP induced GABAergic dysfunction in the PFC, which caused behavioral deficits.

  8. Rates for some reactions involving 42Ca and 44Ca

    International Nuclear Information System (INIS)

    Cheng, C.W.; King, J.D.

    1980-01-01

    Ground-state reaction rates have been deduced from recent cross section measurements for the 42 CA(α, n) 45 Ti, 42 Ca(p, γ) 43 Sc, and 44 Ca(p, n) 44 Sc reactions. Comparison of these rates with those calculated from a statistical model of nuclear reactions. (Woosley et al) shows good agreement for the first two, but the 44 Ca(p, n) rate is more than a factor of 2 less than the theoretical prediction. Stellar reaction rates have been derived from the ground-state rates by multiplying the ground-state rates by the ratio of stellar to ground-state rates given by the statistical model. Both ground-state and stellar rates have been represented by analytic functions of the temperature. The role of these reactions in the approach to quasi-equilibrium during explosive silicon burning is discussed

  9. Experimental and theoretical study on the complexation of Ca2+ with beauvericin

    International Nuclear Information System (INIS)

    Makrlik, E.; Toman, P.; Vanura, P.

    2013-01-01

    From extraction experiments and γ-activity measurements, the exchange extraction constant corresponding to the equilibrium Ca 2+ (aq) + 1 x Sr 2+ (nb) ⇔ 1 x Ca 2+ (nb) + Sr 2+ (aq) taking place in the two-phase water-nitrobenzene system (1 = beauvericin; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K ex (Ca 2+ , 1 x Sr 2+ ) = 1.1 ± 0.1. Further, the stability constant of the 1 x Ca 2+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 deg C: log β nb(1 x Ca 2+ ) = 10.1 ± 0.2. Finally, by using quantum mechanical density functional level of theory calculations, the most probable structures of the non-hydrated 1 x Ca 2+ and hydrated 1 x Ca 2+ x H 2 O complex species were predicted. (author)

  10. Ca 3d unoccupied states in Bi2Sr2CaCu2O8 investigated by Ca L2,3 x-ray-absorption near-edge structure

    International Nuclear Information System (INIS)

    Borg, A.; King, P.L.; Pianetta, P.; Lindau, I.; Mitzi, D.B.; Kapitulnik, A.; Soldatov, A.V.; Della Longa, S.; Bianconi, A.

    1992-01-01

    The high-resolution Ca L 2,3 x-ray-absorption near-edge-structure (XANES) spectrum of a Bi 2 Sr 2 CaCu 2 O 8 single crystal has been measured by use of a magnetic-projection x-ray microscope probing a surface area of 200x200 μm 2 . The Ca L 2,3 XANES spectrum is analyzed by performing a multiple-scattering XANES calculation in real space and comparing the results with the spectrum of CaF 2 . Good agreement between the calculated and experimental crystal-field splitting Δ f of the Ca 3d final states is found and the splitting is shown to be smaller by 0.5 eV than in the initial state. The Ca 3d partial density of states is found to be close to the Fermi level in the initial state. The Ca-O(in plane) distance is shown to be a critical parameter associated with the shift of the Ca 3d states relative to the Fermi level; in particular, we have studied the effect of the out-of-plane dimpling mode of the in-plane oxygen atoms O(in plane) that will move the Ca 3d states on or off the Fermi level. This mode can therefore play a role in modulating the charge transfer between the two CuO 2 planes separated by the Ca ions

  11. Ca 3d unoccupied states in Bi2Sr2CaCu2O8 investigated by Ca L2,3 x-ray-absorption near-edge structure

    Energy Technology Data Exchange (ETDEWEB)

    Borg, A; King, P L; Pianetta, P; Lindau, I; Mitzi, D B

    1992-01-01

    The high-resolution Ca L(2,3) x-ray-absorption near-edge-structure (XANES) spectrum of a Bi2Sr2CaCu2O8 single crystal has been measured by use of a magnetic-projection x-ray microscope probing a surface area of 200x200 micrometers square. The Ca L(2,3) XANES spectrum is analyzed by performing a multiple-scattering XANES calculation in real space and comparing the results with the spectrum of CaF2. Good agreement between the calculated and experimental crystal-field splitting Delta f of the Ca 3d final states is found and the splitting is shown to be smaller by 0.5 eV than in the initial state. The Ca 3d partial density of states is found to be close to the Fermi level in the initial state. The Ca-O (in plane) distance is shown to be a critical parameter associated with the shift of the Ca 3d states relative to the Fermi level; in particular, the authors have studied the effect of the out-of-plane dimpling mode of the in-plane oxygen atoms O(in plane) that will move the Ca 3d states on or off the Fermi level. This mode can therefore play a role in modulating the charge transfer between the two CuO2 planes separated by the Ca ions.

  12. Opposite monosynaptic scaling of BLP-vCA1 inputs governs hopefulness- and helplessness-modulated spatial learning and memory.

    Science.gov (United States)

    Yang, Ying; Wang, Zhi-Hao; Jin, Sen; Gao, Di; Liu, Nan; Chen, Shan-Ping; Zhang, Sinan; Liu, Qing; Liu, Enjie; Wang, Xin; Liang, Xiao; Wei, Pengfei; Li, Xiaoguang; Li, Yin; Yue, Chenyu; Li, Hong-Lian; Wang, Ya-Li; Wang, Qun; Ke, Dan; Xie, Qingguo; Xu, Fuqiang; Wang, Liping; Wang, Jian-Zhi

    2016-07-14

    Different emotional states lead to distinct behavioural consequences even when faced with the same challenging events. Emotions affect learning and memory capacities, but the underlying neurobiological mechanisms remain elusive. Here we establish models of learned helplessness (LHL) and learned hopefulness (LHF) by exposing animals to inescapable foot shocks or with anticipated avoidance trainings. The LHF animals show spatial memory potentiation with excitatory monosynaptic upscaling between posterior basolateral amygdale (BLP) and ventral hippocampal CA1 (vCA1), whereas the LHL show memory deficits with an attenuated BLP-vCA1 connection. Optogenetic disruption of BLP-vCA1 inputs abolishes the effects of LHF and impairs synaptic plasticity. By contrast, targeted BLP-vCA1 stimulation rescues the LHL-induced memory deficits and mimics the effects of LHF. BLP-vCA1 stimulation increases synaptic transmission and dendritic plasticity with the upregulation of CREB and intrasynaptic AMPA receptors in CA1. These findings indicate that opposite excitatory monosynaptic scaling of BLP-vCA1 controls LHF- and LHL-modulated spatial memory, revealing circuit-specific mechanisms linking emotions to memory.

  13. Opposite monosynaptic scaling of BLP–vCA1 inputs governs hopefulness- and helplessness-modulated spatial learning and memory

    Science.gov (United States)

    Yang, Ying; Wang, Zhi-Hao; Jin, Sen; Gao, Di; Liu, Nan; Chen, Shan-Ping; Zhang, Sinan; Liu, Qing; Liu, Enjie; Wang, Xin; Liang, Xiao; Wei, Pengfei; Li, Xiaoguang; Li, Yin; Yue, Chenyu; Li, Hong-lian; Wang, Ya-Li; Wang, Qun; Ke, Dan; Xie, Qingguo; Xu, Fuqiang; Wang, Liping; Wang, Jian-Zhi

    2016-01-01

    Different emotional states lead to distinct behavioural consequences even when faced with the same challenging events. Emotions affect learning and memory capacities, but the underlying neurobiological mechanisms remain elusive. Here we establish models of learned helplessness (LHL) and learned hopefulness (LHF) by exposing animals to inescapable foot shocks or with anticipated avoidance trainings. The LHF animals show spatial memory potentiation with excitatory monosynaptic upscaling between posterior basolateral amygdale (BLP) and ventral hippocampal CA1 (vCA1), whereas the LHL show memory deficits with an attenuated BLP–vCA1 connection. Optogenetic disruption of BLP–vCA1 inputs abolishes the effects of LHF and impairs synaptic plasticity. By contrast, targeted BLP–vCA1 stimulation rescues the LHL-induced memory deficits and mimics the effects of LHF. BLP–vCA1 stimulation increases synaptic transmission and dendritic plasticity with the upregulation of CREB and intrasynaptic AMPA receptors in CA1. These findings indicate that opposite excitatory monosynaptic scaling of BLP–vCA1 controls LHF- and LHL-modulated spatial memory, revealing circuit-specific mechanisms linking emotions to memory. PMID:27411738

  14. Sleep deprivation causes memory deficits by negatively impacting neuronal connectivity in hippocampal area CA1

    NARCIS (Netherlands)

    Havekes, Robbert; Park, Alan J; Tudor, Jennifer C; Luczak, Vincent G; Hansen, Rolf T; Ferri, Sarah L; Bruinenberg, Vibeke M; Poplawski, Shane G; Day, Jonathan P; Aton, Sara J; Radwańska, Kasia; Meerlo, Peter; Houslay, Miles D; Baillie, George S; Abel, Ted

    2016-01-01

    Brief periods of sleep loss have long-lasting consequences such as impaired memory consolidation. Structural changes in synaptic connectivity have been proposed as a substrate of memory storage. Here, we examine the impact of brief periods of sleep deprivation on dendritic structure. In mice, we

  15. Defect Study of MgO-CaO Material Doped with CeO2

    Directory of Open Access Journals (Sweden)

    Han Zhang

    2013-01-01

    Full Text Available MgO-CaO refractories were prepared using analytical reagent chemicals of Ca(OH2 and Mg(OH2 as starting materials and CeO2 as dopant, then sintered at 1650°C for 3 h. The effect of CeO2 powders on the defect of MgO-CaO refractories was investigated. The sample characterizations were analyzed by the techniques of XRD and SEM. According to the results, with the addition of CeO2, the lattice constant of CaO increased, and the bulk density of the samples increased while apparent porosity decreased. The densification of MgO-CaO refractories was promoted obviously. In the sintering process, MgO grains grew faster than CaO, pores at the MgO-CaO grain boundaries decreased while pores in the MgO grains increased gradually, and no pores were observed in the CaO grains. The nature of the CeO2 promoting densification lies in the substitution and solution with CaO. Ce4+ approaches into CaO lattices, which enlarges the vacancy concentration of Ca2+ and accelerates the diffusion of Ca2+.

  16. First-principles study on Ca8Cn (n≤12) and CamC12 (m≤8) metal carbides

    International Nuclear Information System (INIS)

    Chen Gang; Peng Qi; Kawazoe, Yoshiyuki

    2011-01-01

    We performed an extensive structure optimization for small Ca 8 C n (n≤12) and Ca m C 12 (m≤8) clusters by using density functional theory. The structure would gain CaC 2 bulk characters for Ca 8 C n with n≥7 and Ca m C 12 with m≥6, respectively. Two cage-like structures were found and their structural stability was evaluated by molecular dynamics simulations. The Ca 4s valence electrons are donated to the π orbitals of dicarbon and part of the donated electrons is back donated to the Ca 3d split orbitals. Both Ca and C atoms contribute to the magnetic properties. The net charge on Ca analyzed with Bader technique is about +1.4e.

  17. Anorexia Reduces GFAP+ Cell Density in the Rat Hippocampus.

    Science.gov (United States)

    Reyes-Haro, Daniel; Labrada-Moncada, Francisco Emmanuel; Varman, Durairaj Ragu; Krüger, Janina; Morales, Teresa; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2016-01-01

    Anorexia nervosa is an eating disorder observed primarily in young women. The neurobiology of the disorder is unknown but recently magnetic resonance imaging showed a volume reduction of the hippocampus in anorexic patients. Dehydration-induced anorexia (DIA) is a murine model that mimics core features of this disorder, including severe weight loss due to voluntary reduction in food intake. The energy supply to the brain is mediated by astrocytes, but whether their density is compromised by anorexia is unknown. Thus, the aim of this study was to estimate GFAP+ cell density in the main regions of the hippocampus (CA1, CA2, CA3, and dentate gyrus) in the DIA model. Our results showed that GFAP+ cell density was significantly reduced (~20%) in all regions of the hippocampus, except in CA1. Interestingly, DIA significantly reduced the GFAP+ cells/nuclei ratio in CA2 (-23%) and dentate gyrus (-48%). The reduction of GFAP+ cell density was in agreement with a lower expression of GFAP protein. Additionally, anorexia increased the expression of the intermediate filaments vimentin and nestin. Accordingly, anorexia increased the number of reactive astrocytes in CA2 and dentate gyrus more than twofold. We conclude that anorexia reduces the hippocampal GFAP+ cell density and increases vimentin and nestin expression.

  18. Dissociations between developmental dyslexias and attention deficits

    Science.gov (United States)

    Lukov, Limor; Friedmann, Naama; Shalev, Lilach; Khentov-Kraus, Lilach; Shalev, Nir; Lorber, Rakefet; Guggenheim, Revital

    2014-01-01

    We examine whether attention deficits underlie developmental dyslexia, or certain types of dyslexia, by presenting double dissociations between the two. We took into account the existence of distinct types of dyslexia and of attention deficits, and focused on dyslexias that may be thought to have an attentional basis: letter position dyslexia (LPD), in which letters migrate within words, attentional dyslexia (AD), in which letters migrate between words, neglect dyslexia, in which letters on one side of the word are omitted or substituted, and surface dyslexia, in which words are read via the sublexical route. We tested 110 children and adults with developmental dyslexia and/or attention deficits, using extensive batteries of reading and attention. For each participant, the existence of dyslexia and the dyslexia type were tested using reading tests that included stimuli sensitive to the various dyslexia types. Attention deficit and its type was established through attention tasks assessing sustained, selective, orienting, and executive attention functioning. Using this procedure, we identified 55 participants who showed a double dissociation between reading and attention: 28 had dyslexia with normal attention and 27 had attention deficits with normal reading. Importantly, each dyslexia with suspected attentional basis dissociated from attention: we found 21 individuals with LPD, 13 AD, 2 neglect dyslexia, and 12 surface dyslexia without attention deficits. Other dyslexia types (vowel dyslexia, phonological dyslexia, visual dyslexia) also dissociated from attention deficits. Examination of 55 additional individuals with both a specific dyslexia and a certain attention deficit found no attention function that was consistently linked with any dyslexia type. Specifically, LPD and AD dissociated from selective attention, neglect dyslexia dissociated from orienting, and surface dyslexia dissociated from sustained and executive attention. These results indicate that

  19. Effect of Deficit Irrigation Treatments on Vegetative Characteristics and Quantity and Quality of Golden Delicious Apple

    Directory of Open Access Journals (Sweden)

    I. Arji

    2016-07-01

    as this formula Q.t = di.a, where Q is volumetric flow rate (liter/Second, t is time based on second, di is net water requirement and a is irrigated area. To evaluate irrigation effects some vegetative (shoot growth and trunk cross sectional area; reproductive (fruit volume, fruit weight and yield and quality (Total soluble solid, total sugar, nitrogen, phosphorous, potassium and calcium traits were measured. Results and Discussion: Results showed that deficit irrigation had no effect on trunk cross sectional area, but shoot growth was affected significantly by deficit irrigation by. So, regulated deficit irrigation (RDI can be used to control excessive vegetative growth in apple trees. There were no significant differences of fruit volume and weight of trees under deficit irrigation than the control exception to secondary 40% treatment. Fruit yield did not have significant differences under early and late 60% treatment in compare to the control. Where yield reduction was only 4 and 8 % in late and early 60% deficit irrigation respectively in compare to full irrigated trees. Water deficit had positive effect on qualitative traits of apple fruit, So that total soluble solids (TSS and total sugar concentration (TSC of fruit were higher in trees subjected to deficit irrigation as compared to the control. Regulated deficit irrigation led to 7-18% and 1.8-15% increase in total soluble solid and total sugar content in compare to full irrigated trees. Relative water content (RWC was significant based of the time of applying deficit irrigation. Deficit irrigation did not have significant effect on fruit minerals such as P and K in compare to the control, but N content had significant reduction in deficit irrigation treatments in compare to the control and Ca fruit content of control trees had significant different in compare to trees were subjected to early deficit irrigation (40% of water requirement.. RDI favored reproductive growth over vegetative growth by suppressing

  20. The synthetic cannabinoid HU210 induces spatial memory deficits and suppresses hippocampal firing rate in rats.

    Science.gov (United States)

    Robinson, L; Goonawardena, A V; Pertwee, R G; Hampson, R E; Riedel, G

    2007-07-01

    Previous work implied that the hippocampal cannabinoid system was particularly important in some forms of learning, but direct evidence for this hypothesis is scarce. We therefore assessed the effects of the synthetic cannabinoid HU210 on memory and hippocampal activity. HU210 (100 microg kg(-1)) was administered intraperitoneally to rats under three experimental conditions. One group of animals were pre-trained in spatial working memory using a delayed-matching-to-position task and effects of HU210 were assessed in a within-subject design. In another, rats were injected before acquisition learning of a spatial reference memory task with constant platform location. Finally, a separate group of animals was implanted with electrode bundles in CA1 and CA3 and single unit responses were isolated, before and after HU210 treatment. HU210 treatment had no effect on working or short-term memory. Relative to its control Tween 80, deficits in acquisition of a reference memory version of the water maze were obtained, along with drug-related effects on anxiety, motor activity and spatial learning. Deficits were not reversed by the CB(1) receptor antagonists SR141716A (3 mg kg(-1)) or AM281 (1.5 mg kg(-1)). Single unit recordings from principal neurons in hippocampal CA3 and CA1 confirmed HU210-induced attenuation of the overall firing activity lowering both the number of complex spikes fired and the occurrence of bursts. These data provide the first direct evidence that the underlying mechanism for the spatial memory deficits induced by HU210 in rats is the accompanying abnormality in hippocampal cell firing.

  1. Effect of sulfation on the surface activity of CaO for N2O decomposition

    International Nuclear Information System (INIS)

    Wu, Lingnan; Hu, Xiaoying; Qin, Wu; Dong, Changqing; Yang, Yongping

    2015-01-01

    Graphical abstract: - Highlights: • Sulfation of CaO (1 0 0) surface greatly deactivates its surface activity for N 2 O decomposition. • An increase of sulfation degree leads to a decrease of CaO surface activity for N 2 O decomposition. • Sulfation from CaSO 3 into CaSO 4 is the crucial step for deactivating the surface activity for N 2 O decomposition. • The electronic interaction CaO (1 0 0)/CaSO 4 (0 0 1) interface is limited to the bottom layer of CaSO 4 (0 0 1) and the top layer of CaO (1 0 0). • CaSO 4 (0 0 1) and (0 1 0) surfaces show negligible catalytic ability for N 2 O decomposition. - Abstract: Limestone addition to circulating fluidized bed boilers for sulfur removal affects nitrous oxide (N 2 O) emission at the same time, but mechanism of how sulfation process influences the surface activity of CaO for N 2 O decomposition remains unclear. In this paper, we investigated the effect of sulfation on the surface properties and catalytic activity of CaO for N 2 O decomposition using density functional theory calculations. Sulfation of CaO (1 0 0) surface by the adsorption of a single gaseous SO 2 or SO 3 molecule forms stable local CaSO 3 or CaSO 4 on the CaO (1 0 0) surface with strong hybridization between the S atom of SO x and the surface O anion. The formed local CaSO 3 increases the barrier energy of N 2 O decomposition from 0.989 eV (on the CaO (1 0 0) surface) to 1.340 eV, and further sulfation into local CaSO 4 remarkably increases the barrier energy to 2.967 eV. Sulfation from CaSO 3 into CaSO 4 is therefore the crucial step for deactivating the surface activity for N 2 O decomposition. Completely sulfated CaSO 4 (0 0 1) and (0 1 0) surfaces further validate the negligible catalytic ability of CaSO 4 for N 2 O decomposition.

  2. [Hereditary factors in attention deficit hyperactivity disorder

    NARCIS (Netherlands)

    Fliers, E.A.; Franke, B.

    2005-01-01

    Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by concentration problems, hyperactivity and impulsivity. Disturbances in dopamine and/or noradrenalin neurotransmission are probably the underlying pathophysiological mechanisms of ADHD. Around 80% of

  3. Remediation of attention deficits in head injury.

    OpenAIRE

    Nag S; Rao S

    1999-01-01

    Head injury is associated with psychological sequelae which impair the patient′s psychosocial functioning. Information processing, attention and memory deficits are seen in head injuries of all severity. We attempted to improve deficits of focused, sustained and divided attention. The principle of overlapping sources of attention resource pools was utilised in devising the remediation programme. Tasks used simple inexpensive materials. Four head injured young adult males with post conc...

  4. Saudi Arabia: persistent but tenable deficits

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    In this article is described the economic situation of Saudi Arabia. In a first time, Saudi Arabia drew from external reserves to finance gulf war and covered its budget deficits, then the internal debts took over. The actual strategy in order to transfer from state to private national and foreign sector a great part of new projects financing is become a necessity to control the deficits in a country where state is strongly got in debt. (N.C.). 2 tabs

  5. Efectos del agregado de cachaza y de diferentes densidades de plantación en la capacidad productiva de un semillero saneado de la variedad de caña de azúcar (Saccharum spp. LCP85-384 Effects of filter cake incorporation and different planting densities on the productive capacity of a healthy LCP85-384 sugarcane variety (Saccharum spp. nursery

    Directory of Open Access Journals (Sweden)

    María I. Cuenya

    2007-06-01

    Full Text Available El alto valor agregado de la semilla saneada de caña de azúcar exige la implementación de diversos manejos culturales que potencien al máximo la productividad de los semilleros. Este trabajo evalúa diferentes alternativas de manejo en la plantación de semilla saneada por termoterapia de la variedad LCP85-384, combinando distintas densidades de yemas con el agregado o no de cachaza en la base del surco. Se implantó un ensayo en Parcelas Divididas con tres repeticiones. Las parcelas principales contemplaron el agregado o no de cachaza. Las subparcelas comprendieron las siguientes densidades de plantación por metro lineal de surco: tres, seis y nueve yemas uninodales; dos y tres trozos de tres yemas cada uno (2 x 3Y y 3 x 3Y, respectivamente y un tallo cortado al medio (8 a 10 yemas. En caña planta y soca 1 se evaluaron número de tallos/parcela, altura promedio de tallos, número de yemas/m lineal del tallo y número de yemas/parcela. Se efectuaron análisis de la varianza y pruebas de comparación de medias (DLS de Fisher. Se detectaron diferencias altamente significativas entre los subtratamientos con respecto al número total de tallos/parcela (caña planta y soca 1 y a la altura promedio de tallos (caña planta. Para ambas variables y en las dos edades de corte, los mayores valores se registraron para los subtratamientos que involucraron trozos de caña y los menores valores para aquellos originados de yemas individuales. Para el número total de yemas/parcela, producidas durante los dos años, se detectaron diferencias altamente significativas entre tratamientos principales y entre subtratamientos. Para esta última variable, de interés en un semillero con dos años de aprovechamiento, el subtratamiento de 3 x 3Y resultó la mejor alternativa de plantación, presentando diferencias significativas con el resto de las densidades ensayadas. La aplicación de cachaza en plantación resultó ventajosa cuando se consideró el

  6. Prenatal nicotine and maternal deprivation stress de-regulate the development of CA1, CA3, and dentate gyrus neurons in hippocampus of infant rats.

    Directory of Open Access Journals (Sweden)

    Hong Wang

    Full Text Available Adverse experiences by the developing fetus and in early childhood are associated with profound effects on learning, emotional behavior, and cognition as a whole. In this study we investigated the effects of prenatal nicotine exposure (NIC, postnatal maternal deprivation (MD or the combination of the two (NIC+MD to determine if hippocampal neuron development is modulated by exposure to drugs of abuse and/or stress. Growth of rat offspring exposed to MD alone or NIC+MD was repressed until after weaning. In CA1 but not CA3 of postnatal day 14 (P14 pups, MD increased pyramidal neurons, however, in dentate gyrus (DG, decreased granule neurons. NIC had no effect on neuron number in CA1, CA3 or DG. Unexpectedly, NIC plus MD combined caused a synergistic increase in the number of CA1 or CA3 neurons. Neuron density in CA regions was unaffected by treatment, but in the DG, granule neurons had a looser packing density after NIC, MD or NIC+MD exposure. When septotemporal axes were analyzed, the synergism of stress and drug exposure in CA1 and CA3 was associated with rostral, whereas MD effects were predominantly associated with caudal neurons. TUNEL labeling suggests no active apoptosis at P14, and doublecortin positive neurons and mossy fibers were diminished in NIC+MD relative to controls. The laterality of the effect of nicotine and/or maternal deprivation in right versus left hippocampus was also analyzed and found to be insiginificant. We report for the first time that early life stressors such as postnatal MD and prenatal NIC exposure, when combined, may exhibit synergistic consequences for CA1 and CA3 pyramidal neuron development, and a potential antagonistic influence on developing DG neurons. These results suggest that early stressors may modulate neurogenesis, apoptosis, or maturation of glutamatergic neurons in the hippocampus in a region-specific manner during critical periods of neurodevelopment.

  7. A Close Association of RyRs with Highly Dense Clusters of Ca2+-activated Cl− Channels Underlies the Activation of STICs by Ca2+ Sparks in Mouse Airway Smooth Muscle

    Science.gov (United States)

    Bao, Rongfeng; Lifshitz, Lawrence M.; Tuft, Richard A.; Bellvé, Karl; Fogarty, Kevin E.; ZhuGe, Ronghua

    2008-01-01

    near to each other, and, moreover, Cl(Ca) channels concentrate in an area with a radius of ∼600 nm, where their density reaches as high as 300 channels/μm2. This model reveals that Cl(Ca) channels are tightly controlled by Ca2+ sparks via local Ca2+ signaling. PMID:18591421

  8. Presenilin 1 Maintains Lysosomal Ca(2+) Homeostasis via TRPML1 by Regulating vATPase-Mediated Lysosome Acidification.

    Science.gov (United States)

    Lee, Ju-Hyun; McBrayer, Mary Kate; Wolfe, Devin M; Haslett, Luke J; Kumar, Asok; Sato, Yutaka; Lie, Pearl P Y; Mohan, Panaiyur; Coffey, Erin E; Kompella, Uday; Mitchell, Claire H; Lloyd-Evans, Emyr; Nixon, Ralph A

    2015-09-01

    Presenilin 1 (PS1) deletion or Alzheimer's disease (AD)-linked mutations disrupt lysosomal acidification and proteolysis, which inhibits autophagy. Here, we establish that this phenotype stems from impaired glycosylation and instability of vATPase V0a1 subunit, causing deficient lysosomal vATPase assembly and function. We further demonstrate that elevated lysosomal pH in Presenilin 1 knockout (PS1KO) cells induces abnormal Ca(2+) efflux from lysosomes mediated by TRPML1 and elevates cytosolic Ca(2+). In WT cells, blocking vATPase activity or knockdown of either PS1 or the V0a1 subunit of vATPase reproduces all of these abnormalities. Normalizing lysosomal pH in PS1KO cells using acidic nanoparticles restores normal lysosomal proteolysis, autophagy, and Ca(2+) homeostasis, but correcting lysosomal Ca(2+) deficits alone neither re-acidifies lysosomes nor reverses proteolytic and autophagic deficits. Our results indicate that vATPase deficiency in PS1 loss-of-function states causes lysosomal/autophagy deficits and contributes to abnormal cellular Ca(2+) homeostasis, thus linking two AD-related pathogenic processes through a common molecular mechanism. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Presenilin 1 Maintains Lysosomal Ca2+ Homeostasis via TRPML1 by Regulating vATPase-Mediated Lysosome Acidification

    Directory of Open Access Journals (Sweden)

    Ju-Hyun Lee

    2015-09-01

    Full Text Available Presenilin 1 (PS1 deletion or Alzheimer’s disease (AD-linked mutations disrupt lysosomal acidification and proteolysis, which inhibits autophagy. Here, we establish that this phenotype stems from impaired glycosylation and instability of vATPase V0a1 subunit, causing deficient lysosomal vATPase assembly and function. We further demonstrate that elevated lysosomal pH in Presenilin 1 knockout (PS1KO cells induces abnormal Ca2+ efflux from lysosomes mediated by TRPML1 and elevates cytosolic Ca2+. In WT cells, blocking vATPase activity or knockdown of either PS1 or the V0a1 subunit of vATPase reproduces all of these abnormalities. Normalizing lysosomal pH in PS1KO cells using acidic nanoparticles restores normal lysosomal proteolysis, autophagy, and Ca2+ homeostasis, but correcting lysosomal Ca2+ deficits alone neither re-acidifies lysosomes nor reverses proteolytic and autophagic deficits. Our results indicate that vATPase deficiency in PS1 loss-of-function states causes lysosomal/autophagy deficits and contributes to abnormal cellular Ca2+ homeostasis, thus linking two AD-related pathogenic processes through a common molecular mechanism.

  10. DISC1 Modulates Neuronal Stress Responses by Gate-Keeping ER-Mitochondria Ca2+ Transfer through the MAM

    Directory of Open Access Journals (Sweden)

    Sung Jin Park

    2017-12-01

    Full Text Available Summary: A wide range of Ca2+-mediated functions are enabled by the dynamic properties of Ca2+, all of which are dependent on the endoplasmic reticulum (ER and mitochondria. Disrupted-in-schizophrenia 1 (DISC1 is a scaffold protein that is involved in the function of intracellular organelles and is linked to cognitive and emotional deficits. Here, we demonstrate that DISC1 localizes to the mitochondria-associated ER membrane (MAM. At the MAM, DISC1 interacts with IP3R1 and downregulates its ligand binding, modulating ER-mitochondria Ca2+ transfer through the MAM. The disrupted regulation of Ca2+ transfer caused by DISC1 dysfunction leads to abnormal Ca2+ accumulation in mitochondria following oxidative stress, which impairs mitochondrial functions. DISC1 dysfunction alters corticosterone-induced mitochondrial Ca2+ accumulation in an oxidative stress-dependent manner. Together, these findings link stress-associated neural stimuli with intracellular ER-mitochondria Ca2+ crosstalk via DISC1, providing mechanistic insight into how environmental risk factors can be interpreted by intracellular pathways under the control of genetic components in neurons. : Park et al. show that DISC1 regulates ER-mitochondria Ca2+ transfer through mitochondria-associated ER membrane (MAM. DISC1 dysfunction at MAM increases ER-mitochondria Ca2+ transfer during oxidative stress and excessive amounts of corticosterone, which impairs mitochondrial function. Keywords: DISC1, MAM, mitochondria, Ca2+, IP3R1, oxidative stress

  11. Adolescent Intermittent Alcohol Exposure: Deficits in Object Recognition Memory and Forebrain Cholinergic Markers.

    Directory of Open Access Journals (Sweden)

    H Scott Swartzwelder

    Full Text Available The long-term effects of intermittent ethanol exposure during adolescence (AIE are of intensive interest and investigation. The effects of AIE on learning and memory and the neural functions that drive them are of particular interest as clinical findings suggest enduring deficits in those cognitive domains in humans after ethanol abuse during adolescence. Although studies of such deficits after AIE hold much promise for identifying mechanisms and therapeutic interventions, the findings are sparse and inconclusive. The present results identify a specific deficit in memory function after AIE and establish a possible neural mechanism of that deficit that may be of translational significance. Male rats (starting at PND-30 received exposure to AIE (5g/kg, i.g. or vehicle and were allowed to mature into adulthood. At PND-71, one group of animals was assessed using the spatial-temporal object recognition (stOR test to evaluate memory function. A separate group of animals was used to assess the density of cholinergic neurons in forebrain areas Ch1-4 using immunohistochemistry. AIE exposed animals manifested deficits in the temporal component of the stOR task relative to controls, and a significant decrease in the number of ChAT labeled neurons in forebrain areas Ch1-4. These findings add to the growing literature indicating long-lasting neural and behavioral effects of AIE that persist into adulthood and indicate that memory-related deficits after AIE depend upon the tasks employed, and possibly their degree of complexity. Finally, the parallel finding of diminished cholinergic neuron density suggests a possible mechanism underlying the effects of AIE on memory and hippocampal function as well as possible therapeutic or preventive strategies for AIE.

  12. CaWingz user's guide

    International Nuclear Information System (INIS)

    Cha, Ben-chin.

    1994-01-01

    This document assumes that you have read and understood the Wingz user's manuals. CaWingz is an external Wingz program which, when combined with a set of script files, provides easy-to-use EPICS channel access interface functions for Wingz users. The external function run allows Wingz user to invoke any Unix processor within caWingz. Few additional functions for accessing static database field and monitoring of value change event is available for EPICS users after release 3.11. The functions, script files, and usage are briefly described in this document. The script files supplied here serve as examples only. Users are responsible for generating their own spreadsheet and script files. CaWingz communicates with IOC through channel access function calls

  13. Characteristics of Primary Care Trusts in financial deficit and surplus - a comparative study in the English NHS.

    Science.gov (United States)

    Badrinath, Padmanabhan; Currell, Rosemary Anne; Bradley, Peter M

    2006-06-01

    Recently the financial status of primary care trusts has come under considerable scrutiny by the government, and financial deficits have been blamed on poor local management of resources. This paper examines the factors that differ between those Primary Care Trusts (PCT) in financial deficit and those in surplus, using readily available data at PCT level. PCTs are the National Health Service organisations in England responsible for improving the health of their population, developing primary and community health services, and commissioning secondary care services. A descriptive comparative study using data from 58 PCTs; 29 in greatest financial surplus and 29 in greatest deficit in the English National Health Service. Nearly half the study deficit PCTs (14 out of 29) are in the East of England and of the 29 surplus PCTs, five each are in Birmingham and Black Country Strategic Health Authority (SHA), and Greater Manchester SHA. The median population density of the deficit PCTs is almost seven times lower than that of surplus PCTs (p = 0.004). Surplus PCTs predominantly serve deprived communities. Nearly half the surplus PCTs are 'spearhead' PCTs compared to only one of the deficit PCTs. Percentage population increase by local authority of the PCT showed that on average deficit PCTs had 2.7 times higher change during 1982-2002 (13.37% for deficit and 4.94% for surplus PCTs). Work pressure felt by staff is significantly higher in deficit PCTs, and they also reported working higher amount of extra hours due to work pressures. The proportion of dispensing general practitioners is significantly higher in deficit PCTs 40.5% vs. 12.9% (p = 0.002). Deficit PCTs on average received pound123 less per head of registered population compared to surplus PCTs. The two groups of PCTs serve two distinct populations with marked differences between the two. Deficit PCTs tend to be in relatively affluent and rural areas. Poor management alone is unlikely to be the cause of deficits

  14. Electric Dipole Polarizability of ^{48}Ca and Implications for the Neutron Skin.

    Science.gov (United States)

    Birkhan, J; Miorelli, M; Bacca, S; Bassauer, S; Bertulani, C A; Hagen, G; Matsubara, H; von Neumann-Cosel, P; Papenbrock, T; Pietralla, N; Ponomarev, V Yu; Richter, A; Schwenk, A; Tamii, A

    2017-06-23

    The electric dipole strength distribution in ^{48}Ca between 5 and 25 MeV has been determined at RCNP, Osaka from proton inelastic scattering experiments at forward angles. Combined with photoabsorption data at higher excitation energy, this enables the first extraction of the electric dipole polarizability α_{D}(^{48}Ca)=2.07(22)  fm^{3}. Remarkably, the dipole response of ^{48}Ca is found to be very similar to that of ^{40}Ca, consistent with a small neutron skin in ^{48}Ca. The experimental results are in good agreement with ab initio calculations based on chiral effective field theory interactions and with state-of-the-art density-functional calculations, implying a neutron skin in ^{48}Ca of 0.14-0.20 fm.

  15. Regulation of the voltage-gated Ca2+ channel CaVα2δ-1 subunit expression by the transcription factor Egr-1.

    Science.gov (United States)

    González-Ramírez, Ricardo; Martínez-Hernández, Elizabeth; Sandoval, Alejandro; Gómez-Mora, Kimberly; Felix, Ricardo

    2018-04-23

    It is well known that the Ca V α 2 δ auxiliary subunit regulates the density of high voltage-activated Ca 2+ channels in the plasma membrane and that alterations in their functional expression might have implications in the pathophysiology of diverse human diseases such as neuropathic pain. However, little is known concerning the transcriptional regulation of this protein. We previously characterized the promoter of Ca V α 2 δ, and here we report its regulation by the transcription factor Egr-1. Using the neuroblastoma N1E-115 cells, we found that Egr-1 interacts specifically with its binding site in the promoter, affecting the transcriptional regulation of Ca V α 2 δ. Overexpression and knockdown analysis of Egr-1 showed significant changes in the transcriptional activity of the Ca V α 2 δ promoter. Egr-1 also regulated the expression of Ca V α 2 δ at the level of protein. Also, functional studies showed that Egr-1 knockdown significantly decreases Ca 2+ currents in dorsal root ganglion (DRG) neurons, while overexpression of the transcription factor increased Ca 2+ currents in the F11 cell line, a hybrid of DRG and N18TG2 neuroblastoma cells. Studying the effects of Egr-1 on the transcriptional expression of Ca V α 2 δ could help to understand the regulatory mechanisms of this protein in both health and disease. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Formation of CaB6 in the thermal decomposition of the hydrogen storage material Ca(BH4)2.

    Science.gov (United States)

    Sahle, Christoph J; Sternemann, Christian; Giacobbe, Carlotta; Yan, Yigang; Weis, Christopher; Harder, Manuel; Forov, Yury; Spiekermann, Georg; Tolan, Metin; Krisch, Michael; Remhof, Arndt

    2016-07-20

    Using a combination of high resolution X-ray powder diffraction and X-ray Raman scattering spectroscopy at the B K- and Ca L2,3-edges, we analyzed the reaction products of Ca(BH4)2 after annealing at 350 °C and 400 °C under vacuum conditions. We observed the formation of nanocrystalline/amorphous CaB6 mainly and found only small contributions from amorphous B for annealing times larger than 2 h. For short annealing times of 0.5 h at 400 °C we observed neither CaB12H12 nor CaB6. The results indicate a reaction pathway in which Ca(BH4)2 decomposes to B and CaH2 and finally reacts to form CaB6. These findings confirm the potential of using Ca(BH4)2 as a hydrogen storage medium and imply the desired cycling capabilities for achieving high-density hydrogen storage materials.

  17. Noradrenergic deficits in Parkinson's disease

    DEFF Research Database (Denmark)

    Nahimi, A.; Sommerauer, M.; Ostergaard, K.

    2017-01-01

    Objectives: In vitro studies suggest that noradrenergic projections from locus coeruleus to subcortical and cortical brain structures, e.g., thalamus, undergo severe neurodegeneration in Parkinson’s disease (PD). Loss of noradrenergic projections may alter oscillatory activity that in turn may...... be associated with cognitive decline. To test this hypothesis of the origin of cognitive decline in this disease, we used positron emission tomography (PET) to quantify the density of noradrenergic projections in groups of PD patients and healthy controls (HC), in combination with neuropsychological assessment...... with cognitive performance, independent of premorbid cognitive function or disease. PD patients had significant slowing of qEEG, e.g., the background alpha rhythm, but only EEG reactivity upon eye opening correlated with thalamic 11C-MeNER BPND in PD patients. Conclusion: This is the first direct quantification...

  18. Schizophrenia and visual backward masking: a general deficit of target enhancement

    Directory of Open Access Journals (Sweden)

    Michael H Herzog

    2013-05-01

    Full Text Available The obvious symptoms of schizophrenia are of cognitive and psychopathological nature. However, schizophrenia affects also visual processing which becomes particularly evident when stimuli are presented for short durations and are followed by a masking stimulus. Visual deficits are of great interest because they might be related to the genetic variations underlying the disease (endophenotype concept. Visual masking deficits are usually attributed to specific dysfunctions of the visual system such as a hypo- or hyper-active magnocellular system. Here, we propose that visual deficits are a manifestation of a general deficit related to the enhancement of weak neural signals as occurring in all other sorts of information processing. We summarize previous findings with the shine-through masking paradigm where a shortly presented vernier target is followed by a masking grating. The mask deteriorates visual processing of schizophrenic patients by almost an order of magnitude compared to healthy controls. We propose that these deficits are caused by dysfunctions of attention and the cholinergic system leading to weak neural activity corresponding to the vernier. High density electrophysiological recordings (EEG show that indeed neural activity is strongly reduced in schizophrenic patients which we attribute to the lack of vernier enhancement. When only the masking grating is presented, EEG responses are roughly comparable between patients and control. Our hypothesis is supported by findings relating visual masking to genetic deviants of the nicotinic 7 receptor (CHRNA7.

  19. Analysis of Budget deficit in Romania during 2000-2013

    OpenAIRE

    Moraru Camelia; Popovici Norina

    2014-01-01

    Worldwide, over time, the years of economic crisis were defined by significant increases in the levels of budget deficits. Discussions on sizing budget deficits, financing, especially the volume of public debt became more intense, both politically and academically. The impact of budget deficit on economic growth is a common theme found in the economic policies adopted. The present paper aims to analyze the evolution of budget deficit and the structural budget deficit in Romania during 2000-20...

  20. Weight loss and bone mineral density.

    Science.gov (United States)

    Hunter, Gary R; Plaisance, Eric P; Fisher, Gordon

    2014-10-01

    Despite evidence that energy deficit produces multiple physiological and metabolic benefits, clinicians are often reluctant to prescribe weight loss in older individuals or those with low bone mineral density (BMD), fearing BMD will be decreased. Confusion exists concerning the effects that weight loss has on bone health. Bone density is more closely associated with lean mass than total body mass and fat mass. Although rapid or large weight loss is often associated with loss of bone density, slower or smaller weight loss is much less apt to adversely affect BMD, especially when it is accompanied with high intensity resistance and/or impact loading training. Maintenance of calcium and vitamin D intake seems to positively affect BMD during weight loss. Although dual energy X-ray absorptiometry is normally used to evaluate bone density, it may overestimate BMD loss following massive weight loss. Volumetric quantitative computed tomography may be more accurate for tracking bone density changes following large weight loss. Moderate weight loss does not necessarily compromise bone health, especially when exercise training is involved. Training strategies that include heavy resistance training and high impact loading that occur with jump training may be especially productive in maintaining, or even increasing bone density with weight loss.

  1. Laboratory Density Functionals

    OpenAIRE

    Giraud, B. G.

    2007-01-01

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  2. Color perception deficits in co-existing attention-deficit/hyperactivity disorder and chronic tic disorders

    NARCIS (Netherlands)

    Roessner, V.; Banaschewski, T.; Fillmer-Otte, A.; Becker, A.; Albrecht, B.; Uebel, H.; Sergeant, J.A.; Tannock, R.; Rothenberger, A.

    2008-01-01

    Preliminary findings suggest that color perception, particularly of blue-yellow stimuli, is impaired in attention-deficit/hyperactivity disorder (ADHD) as well as in chronic tic disorders (CTD). However, these findings have been not replicated and it is unclear what these deficits mean for the

  3. Beyond Auditory Sensory Processing Deficits: Lexical Tone Perception Deficits in Chinese Children with Developmental Dyslexia

    Science.gov (United States)

    Tong, Xiuhong; Tong, Xiuli; King Yiu, Fung

    2018-01-01

    Increasing evidence suggests that children with developmental dyslexia exhibit a deficit not only at the segmental level of phonological processing but also, by extension, at the suprasegmental level. However, it remains unclear whether such a suprasegmental phonological processing deficit is due to a difficulty in processing acoustic cues of…

  4. Story Comprehension and Academic Deficits in Children with Attention Deficit Hyperactivity Disorder: What Is the Connection?

    Science.gov (United States)

    Berthiaume, Kristen S.

    2006-01-01

    Based on the reliable findings that children with attention deficit hyperactivity disorder (ADHD) have both attentional and academic difficulties, it is assumed that the attentional deficit contributes to the academic problems. In this article, existing support for a link between the attentional and academic difficulties experienced by children…

  5. Stark broadening of Ca IV spectral lines of astrophysical interest

    Science.gov (United States)

    Alonso-Medina, A.; Colón, C.

    2014-12-01

    Ca IV emission lines are under the preview of Solar Ultraviolet Measurements of Emitted Radiation device aboard the Solar and Heliospheric Observatory. Also, lines of the Ca IV in planetary nebulae NGC 7027 were detected with the Short Wavelength Spectrometer on board the Infrared Space Observatory. These facts justify an attempt to provide new spectroscopic parameters of Ca IV. There are no theoretical or experimental Stark broadening data for Ca IV. Using the Griem semi-empirical approach and the COWAN code, we report in this paper calculated values of the Stark broadening parameters for 467 lines of Ca IV. They were calculated using a set of wavefunctions obtained by using Hartree-Fock relativistic calculations. These lines arising from 3s23p4ns (n = 4, 5), 3s23p44p, 3s23p4nd (n = 3, 4) configurations. Stark widths and shifts are presented for an electron density of 1017 cm-3 and temperatures T = 10 000, 20 000 and 50 200 K. As these data cannot be compared to others in the literature, we present an analysis of the different regularities of the values presented in this work.

  6. The CaO orange system in meteor spectra

    Science.gov (United States)

    Berezhnoy, A. A.; Borovička, J.; Santos, J.; Rivas-Silva, J. F.; Sandoval, L.; Stolyarov, A. V.; Palma, A.

    2018-02-01

    The CaO orange band system was simulated in the region 5900-6300 Å and compared with the experimentally observed spectra of Benešov bolide wake. The required vibronic Einstein emission coefficients were estimated by means of the experimental radiative lifetimes under the simplest Franck-Condon approximation. A moderate agreement was achieved, and the largest uncertainties come from modeling shape of FeO orange bands. Using a simple model the CaO column density in the wake of the Benešov bolide at the height of 29 km was estimated as (5 ± 2) × 1014 cm-2 by a comparison of the present CaO spectra with the AlO bands nicely observed at 4600-5200 Å in the same spectrum. The obtained CaO content is in a good agreement with the quenching model developed for the impact-produced cloud, although future theoretical and experimental studies of both CaO and FeO orange systems contribution would be needed to confirm these results.

  7. Compression characteristics and permeability of saturated Gaomiaozi ca-bentonite

    International Nuclear Information System (INIS)

    Sun Wenjing; Sun De'an; Fang Lei

    2012-01-01

    The compression characteristics and permeability of compacted Gaomiaozi Ca-bentonite saturated by the water uptake tests are studied by conducting a series of one-dimension compression tests. The permeability coefficient can be calculated by the Terzaghi's one-dimensional consolidation theory after the consolidation coefficient is obtained by the square root of time method. It is found that the compression curves of compacted specimens saturated by the water uptake tests tend to be consistent in the relatively high stress range. The compression indexes show a linear decrease with increasing dry density and the swelling index is a constant. The permeability coefficient decreases with increasing compression stress, and they show the linear relationship in double logarithmic coordinates. Meanwhile, the permeability coefficient shows a linear decrease with decreasing void ratio, which has no relationship with initial states, stress states and stress paths. The permeability coefficient k of GMZ Ca-bentonite at dry density Pd of 1.75 g/cm 3 can be calculated as 2.0 × 10 -11 cm/s by the linear relationship between Pd and log k. It is closed to the permeability coefficient of GMZ Ca-bentonite with the same dry density published in literature, which testifies that the method calculating the permeability coefficient is feasible from the consolidation coefficient obtained by the consolidation test. (authors)

  8. Comparative Study of Electronic Structure and Magnetic Properties of Osmate Double Perovskites: Ca2FeOsO6 versus Ca2Co(Ni)OsO6

    Science.gov (United States)

    Samanta, Kartik; Saha-Dasgupta, Tanusri

    2018-04-01

    Employing density functional theory, we study the trend in the electronic and magnetic properties of 3d-5d double perovskites, upon varying the 3d element for a fixed choice of 5d element, namely Ca2BOsO6 (B = Fe/Co/Ni). While all three compounds are reported to be ferrimagnets, the magnetic transition temperature of Ca2FeOsO6 is reported to be 2-2.4 times larger than that of Ca2CoOsO6 or Ca2NiOsO6. Our first-principles study provides microscopic insight into this trend. This trend is found to be caused by the downward shift in the position of d level energies of the B site element with respect to that of the Os t2g level upon moving across the 3d series from Fe to Co and Ni. This in turn changes the nominal valence of the Os ion from 5+ in Ca2FeOsO6 to 6+ in Ca2CoOsO6 and Ca2NiOsO6, resulting in differing superexchange paths between Ca2FeOsO6 and Ca2Co(Ni)OsO6, and additionally enabling the hybridization-mechanism-driven magnetism in Ca2FeOsO6. These together significantly enhance the magnetic transition temperature in Ca2FeOsO6 compared with that in Ca2Co(Ni)OsO6.

  9. Weak transitions in 44Ca

    International Nuclear Information System (INIS)

    Tauhata, L.; Marques, A.

    1972-01-01

    Energy levels and gamma radiation transitions of Ca 44 are experimentally determined, mainly the weak transition at 564 KeV and 728 KeV. The decay scheme and the method used (coincidence with Ge-Li detector) are also presented [pt

  10. Electronic Structure and Thermoelectric Properties of Ca3 Co4O9

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The relation among electronic structure, chemical bond and thermoelectric property of Ca3 Co4 O9 was studied using density function and discrete variation method (DFT-DVM).The gap between the highest valence band (HVB) and the lowest conduction band (LCB) shows a semiconducting property.Ca3 Co4 O9 colsists of CoO2 and Ca2 CoO3 two layers.The HVB and LCB near Fermi level are only mainly from O(2) 2p and Co(2) 3d in Ca2 CoO3 layer. Therefore, the semiconducting or thermoelectric property of Ca3 Co4 O9 should be mainly from Ca2 CoO3 layer, but it seems to have no direct relation to the CoO2 layer,which is consistent with that binary oxides hardly have a thermoelectric property, but trinary oxide compounds have quite a good thermoelectric property.The covalent and ionic bonds of Ca2 CoO3 layer are both weaker than those of CoO2 layer.Ca plays the role of connections between CoO2 and Ca2 CoO3 layers in Ca3 Co4 O9, decrease the ionic and covalent bond strength, and improve the thermoelectric property.

  11. Social communication deficits: Specific associations with Social Anxiety Disorder.

    Science.gov (United States)

    Halls, Georgia; Cooper, Peter J; Creswell, Cathy

    2015-02-01

    Social communication deficits are prevalent amongst children with anxiety disorders; however whether they are over-represented specifically among children with Social Anxiety Disorder has not been examined. This study set out to examine social communication deficits among children with Social Anxiety Disorder in comparison to children with other forms of anxiety disorder. Parents of 404 children with a diagnosed anxiety disorder completed the Social Communication Questionnaire (SCQ; Rutter, M., Bailey, A., Lord, C., 2003. The Social Communication Questionnaire - Manual. Western Psychological Services, Los Angeles, CA). Children with a diagnosis of Social Anxiety Disorder (n=262) and anxious children without Social Anxiety Disorder (n=142) were compared on SCQ total and subscale scores and the frequency of participants scoring above clinical cut-offs. Children with Social Anxiety Disorder scored significantly higher than anxious children without Social Anxiety Disorder on the SCQ total (t(352)=4.85, p<.001, d=.55, r=.27), Reciprocal Social Interaction (t(351)=4.73, p<.001, d=.55, r=.27), communication (t(344)=3.62, p<.001, d=.43, r=.21) and repetitive, restrictive and stereotyped behaviors subscales (t(353)=3.15, p=.002, d=.37, r=.18). Furthermore, children with Social Anxiety Disorder were three times more likely to score above clinical cut-offs. The participants were a relatively affluent group of predominantly non-minority status. The social communication difficulties measure relied on parental report which could be influenced by extraneous factors. Treatments for Social Anxiety Disorder may benefit from a specific focus on developing social communication skills. Future research using objective assessments of underlying social communication skills is required. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Moderate injury in motor-sensory cortex causes behavioral deficits accompanied by electrophysiological changes in mice adulthood.

    Directory of Open Access Journals (Sweden)

    Wei Ouyang

    Full Text Available Moderate traumatic brain injury (TBI in children often happen when there's a sudden blow to the frontal bone, end with long unconscious which can last for hours and progressive cognitive deficits. However, with regard to the influences of moderate TBI during children adulthood, injury-induced alterations of locomotive ability, long-term memory performance, and hippocampal electrophysiological firing changes have not yet been fully identified. In this study, lateral fluid percussion (LFP method was used to fabricate moderate TBI in motor and somatosensory cortex of the 6-weeks-old mice. The motor function, learning and memory function, extracellular CA1 neural spikes were assessed during acute and subacute phase. Moreover, histopathology was performed on day post injury (DPI 16 to evaluate the effect of TBI on tissue and cell morphological changes in cortical and hippocampal CA1 subregions. After moderate LFP injury, the 6-weeks-old mice showed severe motor deficits at the early stage in acute phase but gradually recovered later during adulthood. At the time points in acute and subacute phase after TBI, novel object recognition (NOR ability and spatial memory functions were consistently impaired in TBI mice; hippocampal firing frequency and burst probability were hampered. Analysis of the altered burst firing shows a clear hippocampal theta rhythm drop. These electrophysiological impacts were associated with substantially lowered NOR preference as compared to the sham group during adulthood. These results suggest that moderate TBI introduced at motorsenory cortex in 6-weeks-old mice causes obvious motor and cognitive deficits during their adulthood. While the locomotive ability progressively recovers, the cognitive deficits persisted while the mice mature as adult mice. The cognitive deficits may be attributed to the general suppressing of whole neural network, which could be labeled by marked reduction of excitability in hippocampal CA1

  13. Moderate injury in motor-sensory cortex causes behavioral deficits accompanied by electrophysiological changes in mice adulthood.

    Science.gov (United States)

    Ouyang, Wei; Yan, Qichao; Zhang, Yu; Fan, Zhiheng

    2017-01-01

    Moderate traumatic brain injury (TBI) in children often happen when there's a sudden blow to the frontal bone, end with long unconscious which can last for hours and progressive cognitive deficits. However, with regard to the influences of moderate TBI during children adulthood, injury-induced alterations of locomotive ability, long-term memory performance, and hippocampal electrophysiological firing changes have not yet been fully identified. In this study, lateral fluid percussion (LFP) method was used to fabricate moderate TBI in motor and somatosensory cortex of the 6-weeks-old mice. The motor function, learning and memory function, extracellular CA1 neural spikes were assessed during acute and subacute phase. Moreover, histopathology was performed on day post injury (DPI) 16 to evaluate the effect of TBI on tissue and cell morphological changes in cortical and hippocampal CA1 subregions. After moderate LFP injury, the 6-weeks-old mice showed severe motor deficits at the early stage in acute phase but gradually recovered later during adulthood. At the time points in acute and subacute phase after TBI, novel object recognition (NOR) ability and spatial memory functions were consistently impaired in TBI mice; hippocampal firing frequency and burst probability were hampered. Analysis of the altered burst firing shows a clear hippocampal theta rhythm drop. These electrophysiological impacts were associated with substantially lowered NOR preference as compared to the sham group during adulthood. These results suggest that moderate TBI introduced at motorsenory cortex in 6-weeks-old mice causes obvious motor and cognitive deficits during their adulthood. While the locomotive ability progressively recovers, the cognitive deficits persisted while the mice mature as adult mice. The cognitive deficits may be attributed to the general suppressing of whole neural network, which could be labeled by marked reduction of excitability in hippocampal CA1 subregion.

  14. Prevalence and profile of cognitive deficits in a cohort of first-episode antipsychotic-naïve schizophrenia patients

    DEFF Research Database (Denmark)

    Jensen, Maria Høj; Glenthøj, Birte Yding; Nielsen, Mette Ødegaard

    2014-01-01

    first-episode antipsychotic-naïve schizophrenia patients and 60 matched healthy controls have been examined at baseline. The study uses several instruments, including BACS (Brief Assessment of Cognition in Schizophrenia) and CANTAB (Cambridge Neuropsychological Test Automated Battery). Premorbid......Background and Aims: Cognitive deficits are considered a core feature of schizophrenia with prevalence estimates ranging from ca. 75-85 %. These deficits are present in the early phase of the illness; however in most first-episode schizophrenia studies the patients are receiving antipsychotic...... medication, which can affect the results on specific domains such as processing speed. As part of the PECANS project (Pan European Collaboration on Antipsychotic Naïve Schizophrenia) the aim of the present study is to establish the prevalence and profile of cognitive deficits in a cohort of first...

  15. Control of ciliary motility by Ca2+: Integration of Ca2+-dependent functions and targets for Ca2+ action

    International Nuclear Information System (INIS)

    Evans, T.C.

    1988-01-01

    To identify functions that regulate Ca 2+ -induced ciliary reversal in Paramecium, mutants defective in terminating depolarization-induced backward swimming were selected. Six independent recessive mutations (k-shy) comprising two complementation groups, k-shyA and k-shyB, were identified. All mutants exhibited prolonged backward swimming in depolarizing solutions. Voltage clamp studies revealed that mutant Ca 2+ current amplitudes were reduced, but could be restored to wild type levels by EGTA injection. The recovery of the mutant Ca 2+ current from Ca 2+ -dependent inactivation, and the decay of the Ca 2+ -dependent K + and Ca 2+ -dependent Na + currents after depolarization were slow in k-shy compared to wild type. To identify protein targets of Ca 2+ action, ciliary proteins that interact with calmodulin (CaM) were characterized. With a 125 I-CaM blot assay, several CaM-binding proteins were identified including axonemal, soluble, and membrane-bound polypeptides. Competitive displacement studies with unlabeled Paramecium CaM, bovine CaM, and troponinC suggested that both protein types bind CaM with high affinity and specificity. To examine the presence of CaM-binding sites in intact axonemes, a filtration binding assay was developed

  16. Ca isotopic fractionation patterns in forest ecosystems

    Science.gov (United States)

    Kurtz, A. C.; Takagi, K.

    2012-12-01

    Calcium stable isotope ratios are an emerging tracer of the biogeochemical cycle of Ca that are just beginning to see significant application to forest ecosystems. The primary source of isotopic fractionation in these systems is discrimination against light Ca during uptake by plant roots. Cycling of vegetation-fractionated Ca establishes isotopically distinct Ca pools within a forest ecosystem. In some systems, the shallow soil exchangeable Ca pool is isotopically heavy relative to Ca inputs. This has been explained by preferential removal of light Ca from the soil. In other systems, the soil exchange pool is isotopically light relative to inputs, which is explained by recycling of plant-fractionated light Ca back into soil. Thus vegetation uptake of light Ca has been called on to account for both isotopically heavy and light Ca in the shallow soil exchange pools. We interpret patterns in ecosystem δ44Ca with the aid of a simple box model of the forest Ca cycle. We suggest that the δ44Ca of exchangeable Ca in the shallow soil pool primarily reflects the relative magnitude of three key fluxes in a forest Ca cycle, 1) the flux of external Ca into the system via weathering or atmospheric deposition, 2) the uptake flux of Ca from soils into the vegetation pool, and 3) the return flux of Ca to shallow soils via remineralization of leaf litter. Two observations that emerge from our model may aid in the application of Ca isotopes to provide insight into the forest Ca cycle. First, regardless of the magnitude of both vegetation Ca uptake and isotopic fractionation, the δ44Ca of the soil exchange pool will equal the input δ44Ca unless the plant uptake and remineralization fluxes are out of balance. A second observation is that the degree to which the shallow soil exchange pool δ44Ca can differ from the input ratio is controlled by the relative rates of biological uptake and external Ca input. Significant differences between soil exchange and input δ44Ca are seen only

  17. Neuropsychological deficits in patients with Lyme borreliosis

    Directory of Open Access Journals (Sweden)

    Katja Pruša

    2001-09-01

    Full Text Available Slovenia is an endemic area for Lyme borreliosis, a disease that affects many organic systems. Decline in cognitive abilities and emotional changes can appear in acute and chronic stage of the disease beside somatic difficulties. Early antibiotic therapy is of great importance in recovery. Attention and concentration deficits, memory deficits, impaired executive functioning, depression and other symptoms reduce work efficiency and life quality of people with Lyme borreliosis. Neuropsychological deficits can be explained with central nervous system impairment and partly also with reactive psychological factors. On account of symptomatic complexity, broad differential diagnostic and unreliable diagnostic technology neuropsychological evaluation can help to correctly diagnose and accurately treat this disease, and thus to enable appropriate cognitive rehabilitation and psychotherapeutic assistance.

  18. Densities of carbon foils

    International Nuclear Information System (INIS)

    Stoner, J.O. Jr.

    1991-01-01

    The densities of arc-evaporated carbon target foils have been measured by several methods. The density depends upon the method used to measure it; for the same surface density, values obtained by different measurement techniques may differ by fifty percent or more. The most reliable density measurements are by flotation, yielding a density of 2.01±0.03 g cm -3 , and interferometric step height with the surface density known from auxiliary measurements, yielding a density of 2.61±0.4 g cm -3 . The difference between these density values mayy be due in part to the compressive stresses that carbon films have while still on their substrates, uncertainties in the optical calibration of surface densities of carbon foils, and systematic errors in step-height measurements. Mechanical thickness measurements by micrometer caliper are unreliable due to nonplanarity of these foils. (orig.)

  19. KIDS Nuclear Energy Density Functional: 1st Application in Nuclei

    Science.gov (United States)

    Gil, Hana; Papakonstantinou, Panagiota; Hyun, Chang Ho; Oh, Yongseok

    We apply the KIDS (Korea: IBS-Daegu-Sungkyunkwan) nuclear energy density functional model, which is based on the Fermi momentum expansion, to the study of properties of lj-closed nuclei. The parameters of the model are determined by the nuclear properties at the saturation density and theoretical calculations on pure neutron matter. For applying the model to the study of nuclei, we rely on the Skyrme force model, where the Skyrme force parameters are determined through the KIDS energy density functional. Solving Hartree-Fock equations, we obtain the energies per particle and charge radii of closed magic nuclei, namely, 16O, 28O, 40Ca, 48Ca, 60Ca, 90Zr, 132Sn, and 208Pb. The results are compared with the observed data and further improvement of the model is shortly mentioned.

  20. The history of attention deficit hyperactivity disorder

    Science.gov (United States)

    Reichl, Susanne; Lange, Katharina M.; Tucha, Lara; Tucha, Oliver

    2010-01-01

    The contemporary concept of attention deficit hyperactivity disorder (ADHD) as defined in the DSM-IV-TR (American Psychiatric Association 2000) is relatively new. Excessive hyperactive, inattentive, and impulsive children have been described in the literature since the nineteenth century. Some of the early depictions and etiological theories of hyperactivity were similar to current descriptions of ADHD. Detailed studies of the behavior of hyperactive children and increasing knowledge of brain function have changed the concepts of the fundamental behavioral and neuropathological deficits underlying the disorder. This article presents an overview of the conceptual history of modern-day ADHD. PMID:21258430

  1. The deficit syndrome of schizophrenia: towards heterogeneity.

    Science.gov (United States)

    Thibaut, F; Petit, M

    1997-01-01

    Since the turn of the century, psychiatrists have been concerned with both the unity and diversity of schizophrenia. From these early descriptions until now, many authors have attempted to delineate clinically meaningful subtypes within this disorder. In this connection, negative/positive subtyping has generated great interest. Carpenter and his team have emphasized the origin of the negative symptoms observed. They have proposed that primary enduring negative symptoms should be distinguished from transient negative symptoms resulting from treatment, depression or social deprivation and should be termed deficit symptoms. The validity of this subtyping is supported by clinical, biochemical or electrophysiological studies showing differences between deficit and nondeficit patients.

  2. Loss of mTOR-Dependent Macroautophagy Causes Autistic-like Synaptic Pruning Deficits

    OpenAIRE

    Tang, Guomei; Gudsnuk, Kathryn; Kuo, Sheng-Han; Cotrina, Marisa L.; Rosoklija, Gorazd; Sosunov, Alexander; Sonders, Mark S.; Kanter, Ellen; Castagna, Candace; Yamamoto, Ai; Yue, Zhenyu; Arancio, Ottavio; Peterson, Bradley S.; Champagne, Frances; Dwork, Andrew J.

    2014-01-01

    Developmental alterations of excitatory synapses are implicated in autism spectrum disorders (ASDs). Here, we report increased dendritic spine density with reduced developmental spine pruning in layer V pyramidal neurons in postmortem ASD temporal lobe. These spine deficits correlate with hyperactivated mTOR and impaired autophagy. In Tsc2+/- ASD mice where mTOR is constitutively overactive, we observed postnatal spine pruning defects, blockade of autophagy, and ASD-like social...

  3. Wake deficit measurements on the Jess and Souza Ranches, Altamont Pass

    Energy Technology Data Exchange (ETDEWEB)

    Nierenburg, R. (Altamont Energy Corp., San Rafael, CA (USA))

    1990-04-01

    This report is ninth in a series of documents presenting the findings of field test under DOE's Cooperative Field Test Program (CFTP) with the wind industry. This report provides results of a project conducted by Altamont Energy Corp. (AEC) to measure wake deficits on the Jess and Sousa Ranches in Altamont Pass, CA. This research enhances and complements other DOE-funded projects to refine estimates of wind turbine array effects. This project will help explain turbine performance variability caused by wake effects. 4 refs., 28 figs., 106 tabs.

  4. Long-term Ameliorative Effects of the Antidepressant Fluoxetine Exposure on Cognitive Deficits in 3 × TgAD Mice.

    Science.gov (United States)

    Jin, Li; Gao, Li-Feng; Sun, Dong-Sheng; Wu, Hao; Wang, Qun; Ke, Dan; Lei, Hao; Wang, Jian-Zhi; Liu, Gong-Ping

    2017-08-01

    Fluoxetine, a selective serotonin reuptake inhibitor, is neuroprotective; therefore, it has been applied to treat some neurodegenerative disorders. For instance, chronic fluoxetine exposure has short-term effects on Alzheimer's disease (AD). However, the long-term ameliorative effects of fluoxetine exposure on AD have not been reported. In the present study, 6-month-old 3 × TgAD mice were treated with fluoxetine for 15 days, and then the influence of fluoxetine was detected at 20 days after the drug withdrawal. We found that chronic fluoxetine treatment ameliorated cognitive deficits of 3 × TgAD mice and increased the volume of the hippocampal CA1 and dentate gyrus (DG) with increased neuron number and dendritic spine density. Meanwhile, fluoxetine exposure also stimulated the long-term potentiation (LTP) in hippocampal DG. The synaptic-related protein expression increased via activation of the cyclic AMP response element binding (CREB) protein/brain-derived neurotrophic factor (BDNF) signaling pathway induced by fluoxetine exposure. Lastly, we found that fluoxetine treatment decreased beta-amyloid (Aβ) levels. These results further certified that fluoxetine may be a potent effective drug for AD.

  5. Antidepressant-like effects and possible mechanisms of amantadine on cognitive and synaptic deficits in a rat model of chronic stress.

    Science.gov (United States)

    Yu, Mei; Zhang, Yuan; Chen, Xiaoyu; Zhang, Tao

    2016-01-01

    The aim of this study was to examine whether amantadine (AMA), as a low-affinity noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, is able to improve cognitive deficits caused by chronic stress in rats. Male Wistar rats were divided into four groups: control, control + AMA, stress and stress + AMA groups. The chronic stress model combined chronic unpredictable stress (CUS) with isolated feeding. Animals were exposed to CUS continued for 21 days. AMA (25 mg/kg) was administrated p.o. for 20 days from the 4th day of CUS to the 23rd. Weight and sucrose consumption were measured during model establishing period. Spatial memory was evaluated using the Morris water maze (MWM) test. Following MWM testing, both long-term potentiation (LTP) and depotentiation were recorded in the hippocampal CA1 region. NR2B and postsynaptic density protein 95 (PSD-95) proteins were measured by Western-blot analysis. AMA increased weight and sucrose consumption of stressed rats. Spatial memory and reversal learning in stressed rats were impaired relative to controls, whereas AMA significantly attenuated cognitive impairment. AMA also mitigated the chronic stress-induced impairment of hippocampal synaptic plasticity, in which both the LTP and depotentiation were significantly inhibited in stressed rats. Moreover, AMA enhanced the expression of hippocampal NR2B and PSD-95 in stressed rats. The data suggest that AMA may be an effective therapeutic agent for depression-like symptoms and associated cognitive disturbances.

  6. A Devil in the Details: Matrix-Dependent 40Ca42Ca++/42Ca+ and Its Effects on Estimates of the Initial 41Ca/40Ca in the Solar System

    Science.gov (United States)

    McKeegan, K. D.; Liu, M.-C.

    2015-07-01

    Ian Hutcheon established that the molecular ion interference 40Ca42Ca++/42Ca+ on 41K+ is strongly dependent on the mineral analyzed. Correction for this "matrix effect" led to a downward revision of the initial 41Ca/40Ca of the solar system.

  7. Cerebrolysin Ameloriates Cognitive Deficits in Type III Diabetic Rats.

    Directory of Open Access Journals (Sweden)

    Gehan S Georgy

    Full Text Available Cerebrolysin (CBL, a mixture of several active peptide fragments and neurotrophic factors including brain-derived neurotrophic factor (BDNF, is currently used in the management of cognitive alterations in patients with dementia. Since Cognitive decline as well as increased dementia are strongly associated with diabetes and previous studies addressed the protective effect of BDNF in metabolic syndrome and type 2 diabetes; hence this work aimed to evaluate the potential neuroprotective effect of CBL in modulating the complications of hyperglycaemia experimentally induced by streptozotocin (STZ on the rat brain hippocampus. To this end, male adult Sprague Dawley rats were divided into (i vehicle- (ii CBL- and (iii STZ diabetic-control as well as (iv STZ+CBL groups. Diabetes was confirmed by hyperglycemia and elevated glycated haemoglobin (HbA1c%, which were associated by weight loss, elevated tumor necrosis factor (TNF-α and decreased insulin growth factor (IGF-1β in the serum. Uncontrolled hyperglycemia caused learning and memory impairments that corroborated degenerative changes, neuronal loss and expression of caspase (Casp-3 in the hippocampal area of STZ-diabetic rats. Behavioral deficits were associated by decreased hippocampal glutamate (GLU, glycine, serotonin (5-HT and dopamine. Moreover, diabetic rats showed an increase in hippocampal nitric oxide and thiobarbituric acid reactive substances versus decreased non-protein sulfhydryls. Though CBL did not affect STZ-induced hyperglycemia, it partly improved body weight as well as HbA1c%. Such effects were associated by enhancement in both learning and memory as well as apparent normal cellularity in CA1and CA3 areas and reduced Casp-3 expression. CBL improved serum TNF-α and IGF-1β, GLU and 5-HT as well as hampering oxidative biomarkers. In conclusion, CBL possesses neuroprotection against diabetes-associated cerebral neurodegeneration and cognitive decline via anti

  8. Tunneling Evidence of Half-Metallic Ferromagnetism in La(0.7)Ca(0.3)MnO(3)

    Science.gov (United States)

    Wei, J. Y. T.; Yeh, N. C.; Vasquez, R. P.

    1997-01-01

    Direct experimental evidence of half-metallic density of states (DOS) is observed by scanning tunneling spectroscopy on ferromagnetic La(0.7)Ca(0.3)MnO(3) which exhibits colossal magnetoresistance (SMR).

  9. Future Road Density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  10. Restoring neuronal progranulin reverses deficits in a mouse model of frontotemporal dementia.

    Science.gov (United States)

    Arrant, Andrew E; Filiano, Anthony J; Unger, Daniel E; Young, Allen H; Roberson, Erik D

    2017-05-01

    Loss-of-function mutations in progranulin (GRN), a secreted glycoprotein expressed by neurons and microglia, are a common autosomal dominant cause of frontotemporal dementia, a neurodegenerative disease commonly characterized by disrupted social and emotional behaviour. GRN mutations are thought to cause frontotemporal dementia through progranulin haploinsufficiency, therefore, boosting progranulin expression from the intact allele is a rational treatment strategy. However, this approach has not been tested in an animal model of frontotemporal dementia and it is unclear if boosting progranulin could correct pre-existing deficits. Here, we show that adeno-associated virus-driven expression of progranulin in the medial prefrontal cortex reverses social dominance deficits in Grn+/- mice, an animal model of frontotemporal dementia due to GRN mutations. Adeno-associated virus-progranulin also corrected lysosomal abnormalities in Grn+/- mice. The adeno-associated virus-progranulin vector only transduced neurons, suggesting that restoring neuronal progranulin is sufficient to correct deficits in Grn+/- mice. To further test the role of neuronal progranulin in the development of frontotemporal dementia-related deficits, we generated two neuronal progranulin-deficient mouse lines using CaMKII-Cre and Nestin-Cre. Measuring progranulin levels in these lines indicated that most brain progranulin is derived from neurons. Both neuronal progranulin-deficient lines developed social dominance deficits similar to those in global Grn+/- mice, showing that neuronal progranulin deficiency is sufficient to disrupt social behaviour. These data support the concept of progranulin-boosting therapies for frontotemporal dementia and highlight an important role for neuron-derived progranulin in maintaining normal social function. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Panax ginseng extract attenuates neuronal injury and cognitive deficits in rats with vascular dementia induced by chronic cerebral hypoperfusion

    Directory of Open Access Journals (Sweden)

    Jun-De Zhu

    2018-01-01

    Full Text Available Panax ginseng is a slow-growing perennial plant. Panax ginseng extract has numerous biological activities, including antitumor, anti-inflammatory and antistress activities. Panax ginseng extract also has a cognition-enhancing effect in rats with alcohol-induced memory impairment. In this study, we partially occluded the bilateral carotid arteries in the rat to induce chronic cerebral hypoperfusion, a well-known model of vascular dementia. The rats were then intragastrically administered 50 or 100 mg/kg Panax ginseng extract. Morris water maze and balance beam tests were used to evaluate memory deficits and motor function, respectively. Protein quantity was used to evaluate cholinergic neurons. Immunofluorescence staining was used to assess the number of glial fibrillary acidic protein-positive cells. Western blot assay was used to evaluate protein levels of vascular endothelial growth factor, basic fibroblast growth factor, Bcl-2 and Bax. Treatment with Panax ginseng extract for 8 weeks significantly improved behavioral function and increased neuronal density and VEGF and bFGF protein expression in the hippocampal CA3 area. Furthermore, Panax ginseng extract reduced the number of glial fibrillary acidic protein-immunoreactive cells, and it decreased apoptosis by upregulating Bcl-2 and downregulating Bax protein expression. The effect of Panax ginseng extract was dose-dependent and similar to that of nimodipine, a commonly used drug for the treatment of vascular dementia. These findings suggest that Panax ginseng extract is neuroprotective against vascular dementia induced by chronic cerebral hypoperfusion, and therefore might have therapeutic potential for preventing and treating the disease.

  12. Lattice Dynamics of fcc Ca

    DEFF Research Database (Denmark)

    Stassis, C.; Zaretsky, J.; Misemer, D. K.;

    1983-01-01

    A large single crystal of FCC Ca was grown and was used to study the lattice dynamics of this divalent metal by coherent inelastic neutron scattering. The phonon dispersion curves were measured, at room temperature, along the [ξ00], [ξξ0], [ξξξ], and [0ξ1] symmetry directions. The dispersion curves...... to the propagation of elastic waves. The frequencies of the T1[ξξ0] branch for ξ between approximately 0.5 and 0.8 are slightly above the velocity-of-sound line determined from the low-frequency measurements. Since a similar effect has been observed in FCC Yb, it is natural to assume that the anomalous dispersion...... bear a striking resemblance to those of FCC Yb, which is also a divalent metal with an electronic band structure similar to that of Ca. In particular, the shear moduli c44 and (c11-c 12)/2 differ by a factor of 3.4, which implies that FCC Ca (like FCC Yb) is very anisotropic with regard...

  13. Achieving maximum baryon densities

    International Nuclear Information System (INIS)

    Gyulassy, M.

    1984-01-01

    In continuing work on nuclear stopping power in the energy range E/sub lab/ approx. 10 GeV/nucleon, calculations were made of the energy and baryon densities that could be achieved in uranium-uranium collisions. Results are shown. The energy density reached could exceed 2 GeV/fm 3 and baryon densities could reach as high as ten times normal nuclear densities

  14. [A core deficit in Parkinson disease?].

    Science.gov (United States)

    Benítez-Burraco, A; Herrera, E; Cuetos, F

    2016-05-01

    Parkinson disease is a neurodegenerative condition involving motor, cognitive, and linguistic deficits. It is important to know why all these different deficits co-occur in the affected people. This paper aims to clarify whether these comorbid deficits result from the selective impairment of a computational primitive, namely, a context-sensitive computational ability according to Chomsky's Hierarchy (a well-established research tool in comparative neuroscience). A total of 15 medicated subjects with Parkinson disease and 15 controls were selected. They were matched in age and education. A battery of tasks was designed to test 3 different domains (motor capacities, cognition, and language) and 2 different computational abilities (context-free and context-sensitive operations). Significant differences between groups were observed only regarding the linguistic task involving context-sensitive computations (correferences). The observed deficits in our patients with Parkinson disease cannot be explained in terms of the selective impairment of one only unspecific, low-level computational process. At the same time, differences between patients and controls are expected to be greater if the former are not medicated. Moreover, we should pursue in the search of (this kind of) computational primitives than can be selectively impaired in people with Parkinson disease, because they may help to achieve an earlier diagnosis of this condition. Copyright © 2014 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

  15. Intervertebral Disc Characteristic on Progressive Neurological Deficit

    Directory of Open Access Journals (Sweden)

    Farid Yudoyono

    2017-09-01

    Full Text Available Objective: To examine the intervertebral disc characteristic on magnetic resonance imaging (MRI in lumbar herniated disc (LHD patients with progressive neurological deficit. Methods: Patients were collected retrospectively from Dr. Hasan Sadikin General Hospital Database from 2011–2013 with LHD, had neurological deficit such as radiculopathy and cauda equine syndrome for less than four weeks with a positive sign confirmed by neurological examination and confirmatory with MRI examination. Results: A total of 14 patients with lumbar herniated disc disease (10 males, 4 females suffered from progressive neurological deficit with an average age of (52.07±10.9 years old. Early disc height was 9.38±0.5 mm and progressive neurological deficit state disc height was 4.03±0.53 mm, which were significantly different statisticaly (p<0.01. Symptoms of radiculopathy were seen in 11 patients and cauda equine syndrome in three patients. Modic changes grade 1 was found in five patients, grade 2 in eight patients,grade 3 in one patient, Pfirmman grade 2 in eleven patients and grade 3 in three patients. Thecal sac compression 1/3 compression was seen in four patients and 2/3 compression in ten patients. Conclusions: Neurosurgeon should raise concerns on the characteristic changes of intervertebral disc in magnetic resonance imaging examination to avoid further neural injury in lumbar herniated disc patients.

  16. Stigma in attention deficit hyperactivity disorder

    NARCIS (Netherlands)

    Müller, Kathi; Fuermaier, Anselm B M; Koerts, Janneke; Tucha, Lara

    Attention deficit hyperactivity disorder (ADHD) is a frequently diagnosed disorder in child- and adulthood with a high impact affecting multiple facets of social life. Therefore, patients suffering from ADHD are at high risk to be confronted with stigma, prejudices, and discrimination. A review of

  17. Nature, Nurture, and Attention Deficit Hyperactivity Disorder.

    Science.gov (United States)

    Faraone, Stephen V.; Biederman, Joseph

    2000-01-01

    Comments on Joseph's review of the genetics of attention deficit disorder, demonstrating errors of scientific logic and oversight of relevant research in Joseph's argument. Argues for the validity of twin studies in supporting a genetic link for ADHD and for the complementary role of nature and nurture in the etiology of the disorder. (JPB)

  18. Medication Treatment for Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Ryan, Joseph B.; Katsiyannis, Antonis; Hughes, Elizabeth M.

    2011-01-01

    Attention deficit hyperactivity disorder (ADHD) has become the most commonly diagnosed psychiatric disorder among school-age children. For more than half a century, physicians have prescribed medications to help manage behaviors such as hyperactivity, impulsivity, and inattention. Today, there is a growing consensus that ADHD is a biologically…

  19. Reducing the Deficit: Spending and Revenue Options

    Science.gov (United States)

    1994-03-01

    357 B SPENDING OPTIONS BY BUDGET FUNCION ...... 363 TABLES 1. Baseline Deficit Projections, Fiscal Years 1993-2004...direct control of the Congress. abled beneficiaries and beneficiaries with end-stage renal disease. Nonhealth changes enacted in The total that is

  20. ATTENTION DEFICIT/HYPERACTIVITY DISORDER (ADHD)

    African Journals Online (AJOL)

    Enrique

    People who suffer from ADHD are far more likely than normal to drop out of school (32 ... secondary to learning disabilities, partial sensory deficits or even low cognitive ... bad days (Fig. 3), which can lead to frustration for teachers, parents and the child, as there is always the feeling that ... boys who often present very young.

  1. Invest to Improve: The Cybersecurity Talent Deficit

    Science.gov (United States)

    Business-Higher Education Forum, 2017

    2017-01-01

    "Invest to Improve: The Cybersecurity Talent Deficit" provides recommendations for cybersecurity stakeholders--employers, government agencies, and higher education institutions--to enable regional partnerships to meet today's cybersecurity skills needs. This report combines data from a 2017 Gallup survey of business executives and higher…

  2. Linguistic coding deficits in foreign language learners.

    Science.gov (United States)

    Sparks, R; Ganschow, L; Pohlman, J

    1989-01-01

    As increasing numbers of colleges and universities require a foreign language for graduation in at least one of their degree programs, reports of students with difficulties in learning a second language are multiplying. Until recently, little research has been conducted to identify the nature of this problem. Recent attempts by the authors have focused upon subtle but ongoing language difficulties in these individuals as the source of their struggle to learn a foreign language. The present paper attempts to expand upon this concept by outlining a theoretical framework based upon a linguistic coding model that hypothesizes deficits in the processing of phonological, syntactic, and/or semantic information. Traditional psychoeducational assessment batteries of standardized intelligence and achievement tests generally are not sensitive to these linguistic coding deficits unless closely analyzed or, more often, used in conjunction with a more comprehensive language assessment battery. Students who have been waived from a foreign language requirement and their proposed type(s) of linguistic coding deficits are profiled. Tentative conclusions about the nature of these foreign language learning deficits are presented along with specific suggestions for tests to be used in psychoeducational evaluations.

  3. Financing the U.S. Trade Deficit

    National Research Council Canada - National Science Library

    Jackson, James K

    2007-01-01

    The U.S. merchandise trade deficit is a part of the overall U.S. balance of payments, a summary statement of all economic transactions between the residents of the United States and the rest of the world, during a given period of time...

  4. Attention Deficit Hyperactivity Disorder: A Parent's Perspective.

    Science.gov (United States)

    Thompson, Anna M.

    1996-01-01

    A parent and educator who has spent the past 10 years struggling to help her own ADHD (attention deficit-hyperactivity disorder) child offers suggestions for managing the challenges facing such children and enhancing the quality of their lives. Since drug regimens have limitations, parents need to read appropriate literature and receive…

  5. Primary School Teacher's knowledge towards Attention Deficit ...

    African Journals Online (AJOL)

    The work of the teacher becomes much more demanding when some learners have Attention-Deficit/Hyperactivity Disorder (ADHD), as their problems with attention span, impulse control and activity level frequently interfere with activities in the classroom and socially. This study revealed the teachers good knowledge about ...

  6. Magnesium supplementation in children with attention deficit ...

    African Journals Online (AJOL)

    Background: Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with associated mineral deficiency. Aim: To assess magnesium level in ADHD children and compare it to the normal levels in children. Then, to detect the effect of magnesium supplementation as an add on therapy, ...

  7. Did goethe describe attention deficit hyperactivity disorder?

    Science.gov (United States)

    Bonazza, Sara; Scaglione, Cesa; Poppi, Massimo; Rizzo, Giovanni

    2011-01-01

    As early as 1846, the typical symptoms of attention deficit hyperactivity disorder (ADHD) were described by Heinrich Hoffmann (1809-1894). However, in Goethe's masterpiece Faust (1832), the character of Euphorion strongly suggests ADHD diagnosis. Copyright © 2011 S. Karger AG, Basel.

  8. Crowding and Density

    Science.gov (United States)

    Design and Environment, 1972

    1972-01-01

    Three-part report pinpointing problems and uncovering solutions for the dual concepts of density (ratio of people to space) and crowding (psychological response to density). Section one, A Primer on Crowding,'' reviews new psychological and social findings; section two, Density in the Suburbs,'' shows conflict between status quo and increased…

  9. Assessment of sex differences in bone deficits among adolescents with anorexia nervosa.

    Science.gov (United States)

    Nagata, Jason M; Golden, Neville H; Peebles, Rebecka; Long, Jin; Leonard, Mary B; Chang, Audrey O; Carlson, Jennifer L

    2017-04-01

    The objective of this study was to compare sex differences in bone deficits among adolescents with anorexia nervosa (AN) and to identify other correlates of bone health. Electronic medical records of all patients 9-20 years of age with a DSM-5 diagnosis of AN who were evaluated by the eating disorders program at Stanford with dual-energy X-ray absorptiometry (DXA) between March 1997 and February 2011 were retrospectively reviewed. Whole body bone mineral content Z-scores and bone mineral density (BMD) Z-scores at multiple sites were recorded using the Bone Mineral Density in Childhood Study (BMDCS) reference data. A total of 25 males and 253 females with AN were included, with median age 15 years (interquartile range [IQR] 14-17) and median duration of illness 9 months (IQR 5-13). Using linear regression analyses, no significant sex differences in bone deficits were found at the lumbar spine, total hip, femoral neck, or whole body when controlling for age, %mBMI, and duration of illness. Lower %mBMI was significantly associated with bone deficits at all sites in adjusted models. This is the first study to evaluate sex differences in bone health among adolescents with AN, using novel DSM-5 criteria for AN and robust BMDCS reference data. We find no significant sex differences in bone deficits among adolescents with AN except for a higher proportion of females with femoral neck BMD Z-scores <-1. Degree of malnutrition was correlated with bone deficits at all sites. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:352-358). © 2016 Wiley Periodicals, Inc.

  10. Heterogeneity of Developmental Dyscalculia: Cases with Different Deficit Profiles.

    Science.gov (United States)

    Träff, Ulf; Olsson, Linda; Östergren, Rickard; Skagerlund, Kenny

    2016-01-01

    Developmental Dyscalculia (DD) has long been thought to be a monolithic learning disorder that can be attributed to a specific neurocognitive dysfunction. However, recent research has increasingly recognized the heterogeneity of DD, where DD can be differentiated into subtypes in which the underlying cognitive deficits and neural dysfunctions may differ. The aim was to further understand the heterogeneity of developmental dyscalculia (DD) from a cognitive psychological perspective. Utilizing four children (8-9 year-old) we administered a comprehensive cognitive test battery that shed light on the cognitive-behavioral profile of each child. The children were compared against norm groups of aged-matched peers. Performance was then contrasted against predominant hypotheses of DD, which would also give insight into candidate neurocognitive correlates. Despite showing similar mathematical deficits, these children showed remarkable interindividual variability regarding cognitive profile and deficits. Two cases were consistent with the approximate number system deficit account and also the general magnitude-processing deficit account. These cases showed indications of having domain-general deficits as well. One case had an access deficit in combination with a general cognitive deficit. One case suffered from general cognitive deficits only. The results showed that DD cannot be attributed to a single explanatory factor. These findings support a multiple deficits account of DD and suggest that some cases have multiple deficits, whereas other cases have a single deficit. We discuss a previously proposed distinction between primary DD and secondary DD, and suggest hypotheses of dysfunctional neurocognitive correlates responsible for the displayed deficits.

  11. Pharmacologic rescue of motivational deficit in an animal model of the negative symptoms of schizophrenia.

    Science.gov (United States)

    Simpson, Eleanor H; Kellendonk, Christoph; Ward, Ryan D; Richards, Vanessa; Lipatova, Olga; Fairhurst, Stephen; Kandel, Eric R; Balsam, Peter D

    2011-05-15

    Deficits in incentive motivation, the energizing of behavior in pursuit of a goal, occur in many psychiatric disorders including schizophrenia. We previously reported deficits in both cognition and incentive motivation in a transgenic mouse model of increased striatal-specific dopamine D2 receptor (D2R) density (D2R-OE mice). This molecular alteration is observed in patients with schizophrenia, making D2R-OE mice a suitable system to study the cellular and molecular mechanisms of motivation and avolition, as well as a tool for testing potential therapies against motivational deficits. Behavioral studies using operant conditioning methods were performed both to further characterize the incentive motivation deficit in D2R-OE mice and test a novel pharmacological treatment target that arose from an unbiased expression study performed using gene chips and was validated by quantitative reverse transcription polymerase chain reaction, in situ hybridization, and immunohistochemistry. The reluctance of D2R-OE mice to work is due neither to intolerance for low rates of reward, decreased reactivity to reward, nor increased sensitivity to satiety or fatigue but to a difference in willingness to work for reward. As in patients with schizophrenia, this deficit was not ameliorated by D2R blockade, suggesting that reversal of the motivational deficit by switching off the transgene results from molecular changes downstream of D2R overexpression. We observed a reversible increase in serotonin subtype 2C (5-HT2C) receptor expression in D2R-OE mice. Systemic injection of a 5-HT2C receptor antagonist increased incentive motivation in D2R-OE and control mice. We propose that targeting 5-HT2C receptors may be a useful approach to modulate incentive motivation in psychiatric illness. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. Robotic identification of kinesthetic deficits after stroke.

    Science.gov (United States)

    Semrau, Jennifer A; Herter, Troy M; Scott, Stephen H; Dukelow, Sean P

    2013-12-01

    Kinesthesia, the sense of body motion, is essential to proper control and execution of movement. Despite its importance for activities of daily living, no current clinical measures can objectively measure kinesthetic deficits. The goal of this study was to use robotic technology to quantify prevalence and severity of kinesthetic deficits of the upper limb poststroke. Seventy-four neurologically intact subjects and 113 subjects with stroke (62 left-affected, 51 right-affected) performed a robot-based kinesthetic matching task with vision occluded. The robot moved the most affected arm at a preset speed, direction, and magnitude. Subjects were instructed to mirror-match the movement with their opposite arm (active arm). A large number of subjects with stroke were significantly impaired on measures of kinesthesia. We observed impairments in ability to match movement direction (69% and 49% impaired for left- and right-affected subjects, respectively) and movement magnitude (42% and 31%). We observed impairments to match movement speed (32% and 27%) and increased response latencies (48% and 20%). Movement direction errors and response latencies were related to clinical measures of function, motor recovery, and dexterity. Using a robotic approach, we found that 61% of acute stroke survivors (n=69) had kinesthetic deficits. Additionally, these deficits were highly related to existing clinical measures, suggesting the importance of kinesthesia in day-to-day function. Our methods allow for more sensitive, accurate, and objective identification of kinesthetic deficits after stroke. With this information, we can better inform clinical treatment strategies to improve poststroke rehabilitative care and outcomes.

  13. Oculomotor Anomalies in Attention-Deficit/Hyperactivity Disorder: Evidence for Deficits in Response Preparation and Inhibition

    Science.gov (United States)

    Mahone, E. Mark; Mostofsky, Stewart H.; Lasker, Adrian G.; Zee, David; Denckla, Martha B.

    2009-01-01

    Girls, but not boys, with attention deficit hyperactivity disorder (ADHD) have significantly longer visually guided saccades latencies. It is found that sex differences in children with ADHD extend beyond symptom presentation to the development of oculomotor control.

  14. Density of Ga2O3 Liquid

    OpenAIRE

    Dingwell, Donald B.

    1992-01-01

    The density of Ga2O3 liquid in equilibrium with air has been measured at 18000 to 19000C using an Ir double-bob Archimedean method. The data yield the following description of the density of Ga2O3 liquid: ρ= 4.8374(84)–0.00065(12)(T −18500C). This density-temperature relationship is compared with the partial molar volume of Ga2O3 in glasses in the systems CaO–Ga2O3–SiO2 and Na2O–Ga2O3–SiO2, corrected to the glass transition temperature using thermal expansivities. The comparison illustrates t...

  15. Optimization and application of ICPMS with dynamic reaction cell for precise determination of 44Ca/40Ca isotope ratios.

    Science.gov (United States)

    Boulyga, Sergei F; Klötzli, Urs; Stingeder, Gerhard; Prohaska, Thomas

    2007-10-15

    An inductively coupled plasma mass spectrometer with dynamic reaction cell (ICP-DRC-MS) was optimized for determining (44)Ca/(40)Ca isotope ratios in aqueous solutions with respect to (i) repeatability, (ii) robustness, and (iii) stability. Ammonia as reaction gas allowed both the removal of (40)Ar+ interference on (40)Ca+ and collisional damping of ion density fluctuations of an ion beam extracted from an ICP. The effect of laboratory conditions as well as ICP-DRC-MS parameters such a nebulizer gas flow rate, rf power, lens potential, dwell time, or DRC parameters on precision and mass bias was studied. Precision (calculated using the "unbiased" or "n - 1" method) of a single isotope ratio measurement of a 60 ng g(-1) calcium solution (analysis time of 6 min) is routinely achievable in the range of 0.03-0.05%, which corresponded to the standard error of the mean value (n = 6) of 0.012-0.020%. These experimentally observed RSDs were close to theoretical precision values given by counting statistics. Accuracy of measured isotope ratios was assessed by comparative measurements of the same samples by ICP-DRC-MS and thermal ionization mass spectrometry (TIMS) by using isotope dilution with a (43)Ca-(48)Ca double spike. The analysis time in both cases was 1 h per analysis (10 blocks, each 6 min). The delta(44)Ca values measured by TIMS and ICP-DRC-MS with double-spike calibration in two samples (Ca ICP standard solution and digested NIST 1486 bone meal) coincided within the obtained precision. Although the applied isotope dilution with (43)Ca-(48)Ca double-spike compensates for time-dependent deviations of mass bias and allows achieving accurate results, this approach makes it necessary to measure an additional isotope pair, reducing the overall analysis time per isotope or increasing the total analysis time. Further development of external calibration by using a bracketing method would allow a wider use of ICP-DRC-MS for routine calcium isotopic measurements, but it

  16. Perforant path lesioning induces sprouting of CA3-associated fibre systems in mouse hippocampal formation

    DEFF Research Database (Denmark)

    Drøjdahl, Nina; Hegelund, Iørn V; Poulsen, Frantz R

    2002-01-01

    mice. We found that lesioning led to translaminar sprouting of Timm stained regio inferior hippocampus (CA3)-associated fibre systems into the denervated termination zones of the CA3 and dentate gyrus, from the adjacent non-denervated stratum radiatum of CA3. Differences were seen in the Timm staining...... pattern of the two strains of mice, while the response to lesioning appeared similar albeit less pronounced than that observed in the rat. We also observed an intensified acetylcholine esterase staining reflective of cholinergic sprouting in the denervated perforant path termination zones, which...... was particularly prominent in areas with sprouting of Timm stained CA3-associated fibres. Finally, we showed that some of the sprouting fibres within the CA3 were myelinated, due to an increased density of silver impregnated myelinated fibres in this region after lesioning. These results show that the basic...

  17. Attention-Deficit / Hyperactivity Disorder (ADHD): Data and Statistics

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search the CDC Attention-Deficit / Hyperactivity Disorder (ADHD) Note: Javascript is disabled or ... claims to understand diagnosis and treatment patterns for Attention-Deficit/Hyperactivity Disorder (ADHD). On this page you can ...

  18. Children and Adults with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    ... Renew CHADD Annual Conference Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD), is a national nonprofit organization ... ADHD community. © 2017 by Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD). All Rights Reserved. Press Privacy ...

  19. Persistence of attention deficit/hyperactivity disorder into adulthood ...

    African Journals Online (AJOL)

    Persistence of attention deficit/hyperactivity disorder into adulthood: A study conducted on parents of children diagnosed with attention deficit/hyperactivity disorder. ... 10, No 1 (2007) >. Log in or Register to get access to full text downloads.

  20. Attention Deficit Hyperactivity Disorder and Tuberous Sclerosis Complex

    Science.gov (United States)

    ... Privacy Policy Sitemap Learn Engage Donate About TSC Attention Deficit Hyperactivity Disorder and TSC What is ADHD? Attention Deficit Hyperactivity Disorder (ADHD) is a common neurobehavioral disorder. It is ...

  1. The Double-Deficit Hypothesis in Spanish Developmental Dyslexia

    Science.gov (United States)

    Jimenez, Juan E.; Hernandez-Valle, Isabel; Rodriguez, Cristina; Guzman, Remedios; Diaz, Alicia; Ortiz, Rosario

    2008-01-01

    The double-deficit hypothesis (DDH) of developmental dyslexia was investigated in seven to twelve year old Spanish children. It was observed that the double deficit (DD) group had the greatest difficulty with reading.

  2. Multiple C-terminal tail Ca(2+)/CaMs regulate Ca(V)1.2 function but do not mediate channel dimerization.

    Science.gov (United States)

    Kim, Eun Young; Rumpf, Christine H; Van Petegem, Filip; Arant, Ryan J; Findeisen, Felix; Cooley, Elizabeth S; Isacoff, Ehud Y; Minor, Daniel L

    2010-12-01

    Interactions between voltage-gated calcium channels (Ca(V)s) and calmodulin (CaM) modulate Ca(V) function. In this study, we report the structure of a Ca(2+)/CaM Ca(V)1.2 C-terminal tail complex that contains two PreIQ helices bridged by two Ca(2+)/CaMs and two Ca(2+)/CaM-IQ domain complexes. Sedimentation equilibrium experiments establish that the complex has a 2:1 Ca(2+)/CaM:C-terminal tail stoichiometry and does not form higher order assemblies. Moreover, subunit-counting experiments demonstrate that in live cell membranes Ca(V)1.2s are monomers. Thus, contrary to previous proposals, the crystallographic dimer lacks physiological relevance. Isothermal titration calorimetry and biochemical experiments show that the two Ca(2+)/CaMs in the complex have different properties. Ca(2+)/CaM bound to the PreIQ C-region is labile, whereas Ca(2+)/CaM bound to the IQ domain is not. Furthermore, neither of lobes of apo-CaM interacts strongly with the PreIQ domain. Electrophysiological studies indicate that the PreIQ C-region has a role in calcium-dependent facilitation. Together, the data show that two Ca(2+)/CaMs can bind the Ca(V)1.2 tail simultaneously and indicate a functional role for Ca(2+)/CaM at the C-region site.

  3. Multiple Ca2+ sensors in secretion

    DEFF Research Database (Denmark)

    Walter, Alexander M; Groffen, Alexander J; Sørensen, Jakob Balslev

    2011-01-01

    Regulated neurotransmitter secretion depends on Ca(2+) sensors, C2 domain proteins that associate with phospholipids and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) complexes to trigger release upon Ca(2+) binding. Ca(2+) sensors are thought to prevent spontaneous...

  4. Methylphenidate treatment in children with attention deficit hyperactivity disorder and comorbid social phobia.

    Science.gov (United States)

    Golubchik, Pavel; Sever, Jonathan; Weizman, Abraham

    2014-07-01

    The aim of this study was to assess the response of social phobia (SP) symptoms to methylphenidate (MPH) treatment in children with attention deficit hyperactivity disorder (ADHD). Twenty-one ADHD patients with SP, aged between 8 and 18 years, received 12 weeks of MPH treatment. The severity of SP symptoms were assessed by the Liebowitz Social Anxiety Scale for Children and Adolescents (LSAS-CA), and the severity of ADHD symptoms was assessed by the ADHD Rating Scale at baseline and at endpoint. MPH treatment was associated with a significant decrease in the ADHD Rating Scale scores (P<0.0001) and in the total LSAS-CA scores (P=0.013), as well as the school-related items of LSAS-CA (P=0.011). A significant correlation was found between the reductions in ADHD score and total LSAS-CA score (P=0.038), especially in school-related SP. The improvement in ADHD symptoms because of MPH treatment correlates with a parallel improvement in SP. MPH treatment appears to be safe and effective in ADHD/SP children.

  5. Autonomous CaMKII Activity as a Drug Target for Histological and Functional Neuroprotection after Resuscitation from Cardiac Arrest

    Directory of Open Access Journals (Sweden)

    Guiying Deng

    2017-01-01

    Full Text Available The Ca2+/calmodulin-dependent protein kinase II (CaMKII is a major mediator of physiological glutamate signaling, but its role in pathological glutamate signaling (excitotoxicity remains less clear, with indications for both neuro-toxic and neuro-protective functions. Here, the role of CaMKII in ischemic injury is assessed utilizing our mouse model of cardiac arrest and cardiopulmonary resuscitation (CA/CPR. CaMKII inhibition (with tatCN21 or tatCN19o at clinically relevant time points (30 min after resuscitation greatly reduces neuronal injury. Importantly, CaMKII inhibition also works in combination with mild hypothermia, the current standard of care. The relevant drug target is specifically Ca2+-independent “autonomous” CaMKII activity generated by T286 autophosphorylation, as indicated by substantial reduction in injury in autonomy-incompetent T286A mutant mice. In addition to reducing cell death, tatCN19o also protects the surviving neurons from functional plasticity impairments and prevents behavioral learning deficits, even at extremely low doses (0.01 mg/kg, further highlighting the clinical potential of our findings.

  6. Chemical stability and defect formation in CaHfO3

    KAUST Repository

    Alay-E-Abbas, Syed Muhammad

    2014-04-01

    Defects in CaHfO3 are investigated by ab initio calculations based on density functional theory. Pristine and anion-deficient CaHfO 3 are found to be insulating, whereas cation-deficient CaHfO 3 is hole-doped. The formation energies of neutral and charged cation and anion vacancies are evaluated to determine the stability in different chemical environments. Moreover, the energies of the partial and full Schottky defect reactions are computed. We show that clustering of anion vacancies in the HfO layers is energetically favorable for sufficiently high defect concentrations and results in metallicity. © 2014 EPLA.

  7. Chemical stability and defect formation in CaHfO3

    KAUST Repository

    Alay-E-Abbas, Syed Muhammad; Nazir, Safdar; Mun Wong, Kin; Shaukat, Ali; Schwingenschlö gl, Udo

    2014-01-01

    Defects in CaHfO3 are investigated by ab initio calculations based on density functional theory. Pristine and anion-deficient CaHfO 3 are found to be insulating, whereas cation-deficient CaHfO 3 is hole-doped. The formation energies of neutral and charged cation and anion vacancies are evaluated to determine the stability in different chemical environments. Moreover, the energies of the partial and full Schottky defect reactions are computed. We show that clustering of anion vacancies in the HfO layers is energetically favorable for sufficiently high defect concentrations and results in metallicity. © 2014 EPLA.

  8. Phosphorylation of CaMKII in the rat dorsal raphe nucleus plays an important role in sleep-wake regulation.

    Science.gov (United States)

    Cui, Su-Ying; Li, Sheng-Jie; Cui, Xiang-Yu; Zhang, Xue-Qiong; Yu, Bin; Sheng, Zhao-Fu; Huang, Yuan-Li; Cao, Qing; Xu, Ya-Ping; Lin, Zhi-Ge; Yang, Guang; Song, Jin-Zhi; Ding, Hui; Wang, Zi-Jun; Zhang, Yong-He

    2016-02-01

    The Ca(2+) modulation in the dorsal raphe nucleus (DRN) plays an important role in sleep-wake regulation. Calmodulin-dependent kinase II (CaMKII) is an important signal-transducing molecule that is activated by Ca(2+) . This study investigated the effects of intracellular Ca(2+) /CaMKII signaling in the DRN on sleep-wake states in rats. Maximum and minimum CaMKII phosphorylation was detected at Zeitgeber time 21 (ZT 21; wakefulness state) and ZT 3 (sleep state), respectively, across the light-dark rhythm in the DRN in rats. Six-hour sleep deprivation significantly reduced CaMKII phosphorylation in the DRN. Microinjection of the CAMKII activation inhibitor KN-93 (5 or 10 nmol) into the DRN suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REM sleep (NREMS). Application of a high dose of KN-93 (10 nmol) increased slow-wave sleep (SWS) time, SWS bouts, the mean duration of SWS, the percentage of SWS relative to total sleep, and delta power density during NREMS. Microinjection of CaCl2 (50 nmol) in the DRN increased CaMKII phosphorylation and decreased NREMS, SWS, and REMS. KN-93 abolished the inhibitory effects of CaCl2 on NREMS, SWS, and REMS. These data indicate a novel wake-promoting and sleep-suppressing role for the Ca(2+) /CaMKII signaling pathway in DRN neurons. We propose that the intracellular Ca(2+) /CaMKII signaling in the dorsal raphe nucleus (DRN) plays wake-promoting and sleep-suppressing role in rats. Intra-DRN application of KN-93 (CaMKII activation inhibitor) suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REMS (NREMS). Intra-DRN application of CaCl2 attenuated REMS and NREMS. We think these findings should provide a novel cellular and molecular mechanism of sleep-wake regulation. © 2015 International Society for Neurochemistry.

  9. An inhibitory effect of extracellular Ca2+ on Ca2+-dependent exocytosis.

    Directory of Open Access Journals (Sweden)

    Wei Xiong

    Full Text Available AIM: Neurotransmitter release is elicited by an elevation of intracellular Ca(2+ concentration ([Ca(2+](i. The action potential triggers Ca(2+ influx through Ca(2+ channels which causes local changes of [Ca(2+](i for vesicle release. However, any direct role of extracellular Ca(2+ (besides Ca(2+ influx on Ca(2+-dependent exocytosis remains elusive. Here we set out to investigate this possibility on rat dorsal root ganglion (DRG neurons and chromaffin cells, widely used models for studying vesicle exocytosis. RESULTS: Using photolysis of caged Ca(2+ and caffeine-induced release of stored Ca(2+, we found that extracellular Ca(2+ inhibited exocytosis following moderate [Ca(2+](i rises (2-3 µM. The IC(50 for extracellular Ca(2+ inhibition of exocytosis (ECIE was 1.38 mM and a physiological reduction (∼30% of extracellular Ca(2+ concentration ([Ca(2+](o significantly increased the evoked exocytosis. At the single vesicle level, quantal size and release frequency were also altered by physiological [Ca(2+](o. The calcimimetics Mg(2+, Cd(2+, G418, and neomycin all inhibited exocytosis. The extracellular Ca(2+-sensing receptor (CaSR was not involved because specific drugs and knockdown of CaSR in DRG neurons did not affect ECIE. CONCLUSION/SIGNIFICANCE: As an extension of the classic Ca(2+ hypothesis of synaptic release, physiological levels of extracellular Ca(2+ play dual roles in evoked exocytosis by providing a source of Ca(2+ influx, and by directly regulating quantal size and release probability in neuronal cells.

  10. Collective flow in central Ca + Ca and Nb + Nb collisions

    International Nuclear Information System (INIS)

    Fai, G.; Csernai, L.P.; Kapusta, J.I.

    1986-01-01

    Questions related to the entropy, equation of state and collective flow of nuclear matter are important to the authors understanding of high energy nuclear collisions. Completion of the analysis of exclusive measurements on central Ca + Ca and Nb + Nb collisions triggered renewed interest in these problems. In order to address the results of exclusive measurements, however, the complex multifragment final states of high energy nuclear collisions need to be incorporated in a theoretical description. The microcanonical event generator model provides statistically generated complete events that can be compared to the exclusive data on an event-by-event basis. To describe the disassembly of hot nuclear matter the model uses an approximate scheme in which the available final states are populated according to their microcanonical weight in phase space. This statistical description is front-ended with simple geometric ideas to divide the collision system into subsystems and with a prescription to share energy and momentum among the subsystems. Any physical quantity of interest is in principle calculable in the model if sufficient statistics is accumulated

  11. The impact of a budget deficit on inflation in Zimbabwe

    OpenAIRE

    Makochekanwa, Albert

    2008-01-01

    The Zimbabwean economy is one of the many numbers of countries that has experienced a relatively high fiscal deficit for a prolonged period with the result of a high inflationary environment. This paper examines the deficit-inflation nexus in the Zimbabwean economy and establishes the causal link that runs from the budget deficit to the inflation rate using Johansen (1991, 1995) cointegration technique over the period 1980 – 2005. Due to massive monetization of the budget deficit, significant...

  12. Impact of Budget Deficit on Inflation in Zimbabwe

    OpenAIRE

    Albert Makochekanwa

    2011-01-01

    The Zimbabwean economy is one of the countries that once experienced a relatively high fiscal deficit for a prolonged period which resulted in a hyper inflationary environment. This paper examines the deficit-inflation nexus in the Zimbabwean economy and establishes the causal link that runs from the budget deficit to the inflation rate using Johansen (1991, 1995) cointegration technique over the period 1980 to 2005. Due to massive monetization of the budget deficit, significant inflationary ...

  13. Cognitive deficits in the remitted state of unipolar depressive disorder

    DEFF Research Database (Denmark)

    Hasselbalch, Bo Jacob; Knorr, Ulla Benedichte Søsted; Hasselbalch, Steen

    2012-01-01

    Patients with unipolar depressive disorder may present with cognitive deficits in the remitted state, and the aim of the present study was to investigate whether cognitive deficits within specific cognitive domains are present.......Patients with unipolar depressive disorder may present with cognitive deficits in the remitted state, and the aim of the present study was to investigate whether cognitive deficits within specific cognitive domains are present....

  14. Probability densities and Lévy densities

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler

    For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated.......For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated....

  15. Human brain lesion-deficit inference remapped.

    Science.gov (United States)

    Mah, Yee-Haur; Husain, Masud; Rees, Geraint; Nachev, Parashkev

    2014-09-01

    Our knowledge of the anatomical organization of the human brain in health and disease draws heavily on the study of patients with focal brain lesions. Historically the first method of mapping brain function, it is still potentially the most powerful, establishing the necessity of any putative neural substrate for a given function or deficit. Great inferential power, however, carries a crucial vulnerability: without stronger alternatives any consistent error cannot be easily detected. A hitherto unexamined source of such error is the structure of the high-dimensional distribution of patterns of focal damage, especially in ischaemic injury-the commonest aetiology in lesion-deficit studies-where the anatomy is naturally shaped by the architecture of the vascular tree. This distribution is so complex that analysis of lesion data sets of conventional size cannot illuminate its structure, leaving us in the dark about the presence or absence of such error. To examine this crucial question we assembled the largest known set of focal brain lesions (n = 581), derived from unselected patients with acute ischaemic injury (mean age = 62.3 years, standard deviation = 17.8, male:female ratio = 0.547), visualized with diffusion-weighted magnetic resonance imaging, and processed with validated automated lesion segmentation routines. High-dimensional analysis of this data revealed a hidden bias within the multivariate patterns of damage that will consistently distort lesion-deficit maps, displacing inferred critical regions from their true locations, in a manner opaque to replication. Quantifying the size of this mislocalization demonstrates that past lesion-deficit relationships estimated with conventional inferential methodology are likely to be significantly displaced, by a magnitude dependent on the unknown underlying lesion-deficit relationship itself. Past studies therefore cannot be retrospectively corrected, except by new knowledge that would render them redundant

  16. Perceived Cognitive Deficits, Emotional Distress and Disability following Whiplash Injury

    Directory of Open Access Journals (Sweden)

    Michael JL Sullivan

    2002-01-01

    Full Text Available OBJECTIVES: To describe the pattern of perceived cognitive deficits in patients with whiplash injury, to examine the relation between perceived cognitive deficits and disability, and to examine the determinants of perceived cognitive deficits in patients with whiplash injury.

  17. Greenhouse evaluation of deficit irrigation on the growth of tomato ...

    African Journals Online (AJOL)

    Deficit irrigation is considered to be an important approach for crop cultivation in dry regions where water resources are scarce. Deficit irrigation can be used also to decrease the level of infections by some moisturedependent plant pests and diseases such as root-knot nematode disease. Therefore, deficit irrigation at levels ...

  18. Word Processing in Dyslexics: An Automatic Decoding Deficit?

    Science.gov (United States)

    Yap, Regina; Van Der Leu, Aryan

    1993-01-01

    Compares dyslexic children with normal readers on measures of phonological decoding and automatic word processing. Finds that dyslexics have a deficit in automatic phonological decoding skills. Discusses results within the framework of the phonological deficit and the automatization deficit hypotheses. (RS)

  19. Improved Variable Window Kernel Estimates of Probability Densities

    OpenAIRE

    Hall, Peter; Hu, Tien Chung; Marron, J. S.

    1995-01-01

    Variable window width kernel density estimators, with the width varying proportionally to the square root of the density, have been thought to have superior asymptotic properties. The rate of convergence has been claimed to be as good as those typical for higher-order kernels, which makes the variable width estimators more attractive because no adjustment is needed to handle the negativity usually entailed by the latter. However, in a recent paper, Terrell and Scott show that these results ca...

  20. Piracetam improves cognitive deficits caused by chronic cerebral hypoperfusion in rats.

    Science.gov (United States)

    He, Zhi; Liao, Yun; Zheng, Min; Zeng, Fan-Dian; Guo, Lian-Jun

    2008-06-01

    Piracetam is the derivate of gamma-aminobutyric acid, which improves the cognition,memory,consciousness, and is widely applied in the clinical treatment of brain dysfunction. In the present experiments, we study the effects of piracetam on chronic cerebral hypoperfused rats and observe its influence on amino acids, synaptic plasticity in the Perforant path-CA3 pathway and apoptosis in vivo. Cerebral hypoperfusion for 30 days by occlusion of bilateral common carotid arteries induced marked amnesic effects along with neuron damage, including: (1) spatial learning and memory deficits shown by longer escape latency and shorter time spent in the target quadrant; (2) significant neuronal loss and nuclei condensation in the cortex and hippocampus especially in CA1 region; (3) lower induction rate of long term potentiation, overexpression of BAX and P53 protein, and lower content of excitatory and inhibitory amino acids in hippocampus. Oral administration of piracetam (600 mg/kg, once per day for 30 days) markedly improved the memory impairment, increased the amino acid content in hippocampus, and attenuated neuronal damage. The ability of piracetam to attenuate memory deficits and neuronal damage after hypoperfusion may be beneficial in cerebrovascular type dementia.

  1. Electroacupuncture Ameliorates Cognitive Deficit and Improves Hippocampal Synaptic Plasticity in Adult Rat with Neonatal Maternal Separation

    Directory of Open Access Journals (Sweden)

    Lili Guo

    2018-01-01

    Full Text Available Exposure to adverse early-life events is thought to be the risk factors for the development of psychiatric and altered cognitive function in adulthood. The purpose of this study was to investigate whether electroacupuncture (EA treatment in young adult rat would improve impaired cognitive function and synaptic plasticity in adult rat with neonatal maternal separation (MS. Wistar rats were randomly divided into four groups: control group, MS group, MS with EA treatment (MS + EA group, and MS with Sham-EA treatment (MS + Sham-EA group. We evaluated the cognitive function by using Morris water maze and fear conditioning tests. Electrophysiology experiment used in vivo long-term potentiation (LTP at Schaffer Collateral-CA1 synapses was detected to assess extent of synaptic plasticity. Repeated EA stimulation at Baihui (GV 20 and Yintang (GV 29 during postnatal 9 to 11 weeks was identified to significantly ameliorate poor performance in behavior tests and improve the impaired LTP induction detected at Schaffer Collateral-CA1 synapse in hippocampus. Collectively, the findings suggested that early-life stress due to MS may induce adult cognitive deficit associated with hippocampus, and EA in young adult demonstrated that its therapeutic efficacy may be via ameliorating deficit of hippocampal synaptic plasticity.

  2. Doping and defects in YBa2Cu3O7: Results from hybrid density functional theory

    KAUST Repository

    Schwingenschlö gl, Udo; Schuster, Cosima

    2012-01-01

    7 in two prototypical configurations: Ca doped (hole doping) and O deficient (electron doping). By means of first principles calculations for fully relaxed structures, we evaluate the orbital occupations. We find that the change of the charge density

  3. Chronic methamphetamine exposure produces a delayed, long-lasting memory deficit.

    Science.gov (United States)

    North, Ashley; Swant, Jarod; Salvatore, Michael F; Gamble-George, Joyonna; Prins, Petra; Butler, Brittany; Mittal, Mukul K; Heltsley, Rebecca; Clark, John T; Khoshbouei, Habibeh

    2013-05-01

    Methamphetamine (METH) is a highly addictive and neurotoxic psychostimulant. Its use in humans is often associated with neurocognitive impairment. Whether this is due to long-term deficits in short-term memory and/or hippocampal plasticity remains unclear. Recently, we reported that METH increases baseline synaptic transmission and reduces LTP in an ex vivo preparation of the hippocampal CA1 region from young mice. In the current study, we tested the hypothesis that a repeated neurotoxic regimen of METH exposure in adolescent mice decreases hippocampal synaptic plasticity and produces a deficit in short-term memory. Contrary to our prediction, there was no change in the hippocampal plasticity or short-term memory when measured after 14 days of METH exposure. However, we found that at 7, 14, and 21 days of drug abstinence, METH-exposed mice exhibited a deficit in spatial memory, which was accompanied by a decrease in hippocampal plasticity. Our results support the interpretation that the deleterious cognitive consequences of neurotoxic levels of METH exposure may manifest and persist after drug abstinence. Therefore, therapeutic strategies should consider short-term as well as long-term consequences of methamphetamine exposure. Copyright © 2012 Wiley Periodicals, Inc.

  4. Traumatic knee extension deficit (the locked knee)

    DEFF Research Database (Denmark)

    Helmark, I C; Neergaard, K; Krogsgaard, M R

    2007-01-01

    In the present study we investigated the validity of magnetic resonance imaging (MRI) and arthroscopy in knees with acute, traumatic extension deficit (the "locked knee"), and evaluated whether arthroscopy of knees with no mechanical pathology could be avoided by MRI evaluation. The study consisted...... of 50 patients who had an acute, traumatic extension deficit of the knee. All patients were submitted to MRI prior to arthroscopy. Following MRI and surgery, standardized forms were filled out, attempting to objectify the findings. The orthopaedic surgeon was not aware of the MRI result prior to surgery....... Evaluating MRI, all grade-3 meniscal lesions were considered able to cause a mechanical block as well as acute partial or total anterior cruciate ligament (ACL)-ruptures. ACL-ruptures with an old appearance were not considered able to cause locking. Assuming that arthroscopy was the gold standard...

  5. Effect of sulfation on the surface activity of CaO for N{sub 2}O decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Lingnan, E-mail: wulingnan@126.com [School of Energy, Power and Mechanical Engineering, North China Electric Power University, 102206 Beijing (China); National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, 102206 Beijing (China); Hu, Xiaoying, E-mail: huxy@ncepu.edu.cn [National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, 102206 Beijing (China); Qin, Wu, E-mail: qinwugx@126.com [National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, 102206 Beijing (China); Dong, Changqing, E-mail: cqdong1@163.com [National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, 102206 Beijing (China); Yang, Yongping, E-mail: yypncepu@163.com [School of Energy, Power and Mechanical Engineering, North China Electric Power University, 102206 Beijing (China)

    2015-12-01

    Graphical abstract: - Highlights: • Sulfation of CaO (1 0 0) surface greatly deactivates its surface activity for N{sub 2}O decomposition. • An increase of sulfation degree leads to a decrease of CaO surface activity for N{sub 2}O decomposition. • Sulfation from CaSO{sub 3} into CaSO{sub 4} is the crucial step for deactivating the surface activity for N{sub 2}O decomposition. • The electronic interaction CaO (1 0 0)/CaSO{sub 4} (0 0 1) interface is limited to the bottom layer of CaSO{sub 4} (0 0 1) and the top layer of CaO (1 0 0). • CaSO{sub 4} (0 0 1) and (0 1 0) surfaces show negligible catalytic ability for N{sub 2}O decomposition. - Abstract: Limestone addition to circulating fluidized bed boilers for sulfur removal affects nitrous oxide (N{sub 2}O) emission at the same time, but mechanism of how sulfation process influences the surface activity of CaO for N{sub 2}O decomposition remains unclear. In this paper, we investigated the effect of sulfation on the surface properties and catalytic activity of CaO for N{sub 2}O decomposition using density functional theory calculations. Sulfation of CaO (1 0 0) surface by the adsorption of a single gaseous SO{sub 2} or SO{sub 3} molecule forms stable local CaSO{sub 3} or CaSO{sub 4} on the CaO (1 0 0) surface with strong hybridization between the S atom of SO{sub x} and the surface O anion. The formed local CaSO{sub 3} increases the barrier energy of N{sub 2}O decomposition from 0.989 eV (on the CaO (1 0 0) surface) to 1.340 eV, and further sulfation into local CaSO{sub 4} remarkably increases the barrier energy to 2.967 eV. Sulfation from CaSO{sub 3} into CaSO{sub 4} is therefore the crucial step for deactivating the surface activity for N{sub 2}O decomposition. Completely sulfated CaSO{sub 4} (0 0 1) and (0 1 0) surfaces further validate the negligible catalytic ability of CaSO{sub 4} for N{sub 2}O decomposition.

  6. Age-related Changes in Lateral Entorhinal and CA3 Neuron Allocation Predict Poor Performance on Object Discrimination

    Directory of Open Access Journals (Sweden)

    Andrew P. Maurer

    2017-06-01

    Full Text Available Age-related memory deficits correlate with dysfunction in the CA3 subregion of the hippocampus, which includes both hyperactivity and overly rigid activity patterns. While changes in intrinsic membrane currents and interneuron alterations are involved in this process, it is not known whether alterations in afferent input to CA3 also contribute. Neurons in layer II of the lateral entorhinal cortex (LEC project directly to CA3 through the perforant path, but no data are available regarding the effects of advanced age on LEC activity and whether these activity patterns update in response to environmental change. Furthermore, it is not known the extent to which age-related deficits in sensory discrimination relate to the inability of aged CA3 neurons to update in response to new environments. Young and aged rats were pre-characterized on a LEGO© object discrimination task, comparable to behavioral tests in humans in which CA3 hyperactivity has been linked to impairments. The cellular compartment analysis of temporal activity with fluorescence in situ hybridization for the immediate-early gene Arc was then used to identify the principal cell populations that were active during two distinct epochs of random foraging in different environments. This approach enabled the extent to which rats could discriminate two similar objects to be related to the ability of CA3 neurons to update across different environments. In both young and aged rats, there were animals that performed poorly on the LEGO object discrimination task. In the aged rats only, however, the poor performers had a higher percent of CA3 neurons that were active during random foraging in a novel environment, but this is not related to the ability of CA3 neurons to remap when the environment changed. Afferent neurons to CA3 in LEC, as identified with the retrograde tracer choleratoxin B (CTB, also showed a higher percentage of cells that were positive for Arc mRNA in aged poor performing rats

  7. Why Density Dependent Propulsion?

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

  8. Density limits in Tokamaks

    International Nuclear Information System (INIS)

    Tendler, M.

    1984-06-01

    The energy loss from a tokamak plasma due to neutral hydrogen radiation and recycling is of great importance for the energy balance at the periphery. It is shown that the requirement for thermal equilibrium implies a constraint on the maximum attainable edge density. The relation to other density limits is discussed. The average plasma density is shown to be a strong function of the refuelling deposition profile. (author)

  9. Nuclear Level Densities

    International Nuclear Information System (INIS)

    Grimes, S.M.

    2005-01-01

    Recent research in the area of nuclear level densities is reviewed. The current interest in nuclear astrophysics and in structure of nuclei off of the line of stability has led to the development of radioactive beam facilities with larger machines currently being planned. Nuclear level densities for the systems used to produce the radioactive beams influence substantially the production rates of these beams. The modification of level-density parameters near the drip lines would also affect nucleosynthesis rates and abundances

  10. Common Cognitive Deficits in Children with Attention-Deficit/Hyperactivity Disorder and Autism: Working Memory and Visual-Motor Integration

    Science.gov (United States)

    Englund, Julia A.; Decker, Scott L.; Allen, Ryan A.; Roberts, Alycia M.

    2014-01-01

    Cognitive deficits in working memory (WM) are characteristic features of Attention-Deficit/Hyperactivity Disorder (ADHD) and autism. However, few studies have investigated cognitive deficits using a wide range of cognitive measures. We compared children with ADHD ("n" = 49) and autism ("n" = 33) with a demographically matched…

  11. The deficit mechanism of the Hungarian municipalities

    OpenAIRE

    Vasvári, Tamás

    2012-01-01

    The management of the Hungarian municipal sector has received special attention since the crisis in 2008 and interest in the sector increased further due to the changes in legislation in 2011. A great number of economy experts and speakers on behalf of the government or the municipalities provided further details on prevailing issues in the municipal sector, however, their assessment of the severity of these issues varied greatly. By describing the logical framework of the deficit mechanism t...

  12. Sensorimotor gating deficits in multiple system atrophy

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Biernat, Heidi Bryde; Nikolic, Miki

    2014-01-01

    Prepulse inhibition (PPI) of the auditory blink reflex is a measure of sensorimotor gating, which reflects an organism's ability to filter out irrelevant sensory information. PPI has never been studied in patients with multiple system atrophy (MSA), although sensorimotor deficits are frequently a...... associated with synucleinopathies. We investigated whether alterations in PPI were more pronounced in MSA compared with Parkinson's disease (PD), idiopathic rapid eye movement sleep behavior disorder (iRBD) and healthy controls....

  13. ATTENTION DEFICIT HYPERACTIVITY DISORDER. A CLINICAL LECTURE

    OpenAIRE

    A. S. Kotov; M. N. Borisova; M. V. Panteleeva; Yu. V. Matyuk; A. V. Shatalin

    2015-01-01

    Attention deficit hyperactivity disorder (ADHD) is a serious problem to pediatric neurologists. The prevalence of ADHD in developed countries ranges from 1 to 20 %. ADHD is characterized by a triad of symptoms: inattention, hyperactivity, and impulsivity (the International Statistical Classification of Diseases, 10th revision, codes it as F90) and it is the most common conduct disorder in children. The etiology of ADHD remains disсutable to the present day; there are a few basic concepts of t...

  14. Evaluating pollination deficits in pumpkin production in New York.

    Science.gov (United States)

    Petersen, J D; Huseth, A S; Nault, B A

    2014-10-01

    Potential decreases in crop yield from reductions in bee-mediated pollination services threaten food production demands of a growing population. Many fruit and vegetable growers supplement their fields with bee colonies during crop bloom. The extent to which crop production requires supplementary pollination services beyond those provided by wild bees is not well documented. Pumpkin, Cucurbita pepo L., requires bee-mediated pollination for fruit development. Previous research identified the common eastern bumble bee, Bombus impatiens (Cresson), as the most efficient pumpkin pollinator. Two concomitant studies were conducted to examine pollination deficits in New York pumpkin fields from 2011 to 2013. In the first study, fruit weight, seed set, and B. impatiens visits to pumpkin flowers were compared across fields supplemented with B. impatiens colonies at a recommended stocking density of five colonies per hectare, a high density of 15 colonies per hectare, or not supplemented with bees. In the second study, fruit weight and seed set of pumpkins that received supplemental pollen through hand-pollination were compared with those that were open-pollinated by wild bees. Results indicated that supplementing pumpkin fields with B. impatiens colonies, regardless of stocking density, did not increase fruit weight, seed set, or B. impatiens visits to pumpkin flowers. Fruit weight and seed set did not differ between hand- and open-pollinated treatments. In general, we conclude that pumpkin production in central New York is not limited by inadequate pollination services provided by wild bees and that on average, supplementation with B. impatiens colonies did not improve pumpkin yield.

  15. Analysis of the 48Ca neutron skin using a nonlocal dispersive-optical-model self-energy

    Science.gov (United States)

    Atkinson, Mack; Mahzoon, Hossein; Dickhoff, Willem; Charity, Robert

    2017-09-01

    A nonlocal dispersive-optical-model (DOM) analysis of the 40Ca and 48Ca nuclei has been implemented. The real and imaginary potentials are constrained by fitting to elastic-scattering data, total and reaction cross sections, energy level information, particle number, and the charge densities of 40Ca and 48Ca, respectively. The nonlocality of these potentials permits a proper dispersive self-energy which accurately describes both positive and negative energy observables. 48Ca is of particular interest because it is doubly magic and has a neutron skin due to the excess of neutrons. The DOM neutron skin radius is found to be rskin = 0.245 , which is larger than most previous calculations. The neutron skin is closely related to the symmetry energy which is a crucial part of the nuclear equation of state. The combined analysis of 40Ca and 48Ca energy densities provides a description of the density dependence of the symmetry energy which is compared with the 48Ca neutron skin. Results for 208Pb will also become available in the near future. NSF.

  16. Hydrolysis of molten CaCl2-CaF2 with additions of CaO

    Directory of Open Access Journals (Sweden)

    Espen Olsen

    2017-10-01

    Full Text Available Calcium halide based molten salts have recently attracted interest for a number of applications such as direct reduction of oxides for metal production and as liquefying agent in cyclic sorption processes for CO2 by CaO from dilute flue gases (Ca-looping. A fundamental aspect of these melts is the possible hydrolysis reaction upon exposure to gaseous H2O forming corrosive and poisonous hydrogen halides. In this work experiments have been performed investigating the formation of HCl and HF from a molten salt consisting of a 13.8 wt% CaF2 in CaCl2 eutectic exposed to a flowing gas consisting of 10 vol% H2O in N2. Hydrolysis has been investigated as function of content of CaO and temperature. HCl and HF are shown to be formed at elevated temperatures; HCl forms to a substantially larger extent than HF. Addition of CaO has a marked, limiting effect on the hydrolysis. Thermodynamic modeling of the reaction indicates activity coefficients for CaO above unity in the system. For cyclic CO2-capture based on thermal swing, it is advisable to keep the temperature in the carbonation (absorption reactor well below 850 ℃ while maintaining a high CaO content if molten CaCl2 is employed. Similar conclusions can be drawn with regards to CaF2.

  17. Measurement of true density

    International Nuclear Information System (INIS)

    Carr-Brion, K.G.; Keen, E.F.

    1982-01-01

    System for determining the true density of a fluent mixture such as a liquid slurry, containing entrained gas, such as air comprises a restriction in pipe through which at least a part of the mixture is passed. Density measuring means such as gamma-ray detectors and source measure the apparent density of the mixture before and after its passage through the restriction. Solid-state pressure measuring devices are arranged to measure the pressure in the mixture before and after its passage through the restriction. Calculating means, such as a programmed microprocessor, determine the true density from these measurements using relationships given in the description. (author)

  18. Medical Comorbidities in Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Irem Yalug

    2009-09-01

    Full Text Available Attention Deficit Hyperactivity Disorder is one of the most common developmental disorders of childhood with a reported world-wide prevalence of 8 to 12 %. In studies conducted in our country the prevalence rates in community were reported to vary between 8.6 to 8.1 % while clinical prevalence rates were reported to vary between 8.6 to 29.44 %. Fifty to eighty percent of cases were reported to continue into adolescence while thirty to fifty percent may continue into adulthood. Attention deficit hyperactivity disorder is known to accompany subtle physical anomalies, allergic and neurologic disorders, obesity and eating disorders, traumatic injuries, risky sexual behavior, sleep disorders, substance and alcohol use, axis I and II disorders, occupational, legal and academic problems and increased treatment expenditures. Though the effects of this disorder continue throughout life, create burdens to the society along with its treatment as well as disabling the affected patients through their lives, and receive increasing attention in recent years, reviews focusing on problems associated with it are lacking. Therefore, this study aimed to summarize the results of previous studies conducted about medical comorbidities in attention deficit hyperactivity disorder.

  19. Pollination deficits in UK apple orchards

    Directory of Open Access Journals (Sweden)

    Michael Paul Douglas Garratt

    2014-02-01

    Full Text Available Apple production in the UK is worth over £100 million per annum and this production is heavily dependent on insect pollination. Despite its importance, it is not clear which insect pollinators carry out the majority of this pollination. Furthermore, it is unknown whether current UK apple production, in terms of both yield and quality, suffers pollination deficits and whether production value could be increased through effective management of pollination services. The present study set out to address some of these unknowns and showed that solitary bee activity is high in orchards and that they could be making a valuable contribution to pollination. Furthermore, fruit set and apple seed number were found to be suffering potential pollination deficits although these were not reflected in apple quality. Deficits could be addressed through orchard management practices to improve the abundance and diversity of wild pollinators. Such practices include provision of additional floral resources and nesting habitats as well as preservation of semi-natural areas. The cost effectiveness of such strategies would need to be understood taking into account the potential gains to the apple industry.

  20. Pollination deficits in UK apple orchards

    Directory of Open Access Journals (Sweden)

    Simon Potts

    2013-10-01

    Full Text Available Apple production in the UK is worth over £100 million per annum and this production is heavily dependent on insect pollination. Despite its importance, it is not clear which insect pollinators carry out the majority of this pollination. Furthermore, it is unknown whether current UK apple production, in terms of both yield and quality, suffers pollination deficits and whether production value could be increased through effective management of pollination services. The present study set out to address some of these unknowns and showed that solitary bee activity is high in orchards and that they could be making a valuable contribution to pollination. Furthermore, fruit set and apple seed number were found to be suffering potential pollination deficits although these were not reflected in apple quality. Deficits could be addressed through orchard management practices to improve the abundance and diversity of wild pollinators. Such practices include provision of additional floral resources and nesting habitats as well as preservation of semi-natural areas. The cost effectiveness of such strategies would need to be understood taking into account the potential gains to the apple industry.

  1. Acetylcholinesterase inhibition ameliorates deficits in motivational drive

    Directory of Open Access Journals (Sweden)

    Martinowich Keri

    2012-03-01

    Full Text Available Abstract Background Apathy is frequently observed in numerous neurological disorders, including Alzheimer's and Parkinson's, as well as neuropsychiatric disorders including schizophrenia. Apathy is defined as a lack of motivation characterized by diminished goal-oriented behavior and self-initiated activity. This study evaluated a chronic restraint stress (CRS protocol in modeling apathetic behavior, and determined whether administration of an anticholinesterase had utility in attenuating CRS-induced phenotypes. Methods We assessed behavior as well as regional neuronal activity patterns using FosB immunohistochemistry after exposure to CRS for 6 h/d for a minimum of 21 d. Based on our FosB findings and recent clinical trials, we administered an anticholinesterase to evaluate attenuation of CRS-induced phenotypes. Results CRS resulted in behaviors that reflect motivational loss and diminished emotional responsiveness. CRS-exposed mice showed differences in FosB accumulation, including changes in the cholinergic basal forebrain system. Facilitating cholinergic signaling ameliorated CRS-induced deficits in initiation and motivational drive and rescued immediate early gene activation in the medial septum and nucleus accumbens. Conclusions Some CRS protocols may be useful for studying deficits in motivation and apathetic behavior. Amelioration of CRS-induced behaviors with an anticholinesterase supports a role for the cholinergic system in remediation of deficits in motivational drive.

  2. Photoemission study of Ca-intercalated graphite superconductor CaC6

    International Nuclear Information System (INIS)

    Okazaki, Hiroyuki; Yoshida, Rikiya; Iwai, Keisuke; Noami, Kengo; Muro, Takayuki; Nakamura, Tetsuya; Wakita, Takanori; Muraoka, Yuji; Hirai, Masaaki; Tomioka, Fumiaki; Takano, Yoshihiko; Takenaka, Asami; Toyoda, Masahiro; Oguchi, Tamio; Yokoya, Takayoshi

    2010-01-01

    In this work, we have performed resonant photoemission studies of Ca-intercalated graphite superconductor CaC 6 . Using photon energy of the Ca 2p-3d threshold, the photoemission intensity of the peak at Fermi energy (E F ) is resonantly enhanced. This result provides spectroscopic evidence for the existence of Ca 3d states at E F , and strongly supports that Ca 3d state plays a crucial role for the superconductivity of this material with relatively high T c .

  3. Crystal Structures and Mechanical Properties of Ca2C at High Pressure

    Directory of Open Access Journals (Sweden)

    Qun Wei

    2016-07-01

    Full Text Available Recently, a new high-pressure semiconductor phase of Ca2C (space group Pnma was successfully synthesized, it has a low-pressure metallic phase (space group C2/m. In this paper, a systematic investigation of the pressure-induced phase transition of Ca2C is studied on the basis of first-principles calculations. The calculated enthalpy reveals that the phase transition which transforms from C2/m-Ca2C to Pnma-Ca2C occurs at 7.8 GPa, and it is a first-order phase transition with a volume drop of 26.7%. The calculated elastic constants show that C2/m-Ca2C is mechanically unstable above 6.4 GPa, indicating that the structural phase transition is due to mechanical instability. Both of the two phases exhibit the elastic anisotropy. The semiconductivity of Pnma-Ca2C and the metallicity of C2/m-Ca2C have been demonstrated by the electronic band structure calculations. The quasi-direct band gap of Pnma-Ca2C at 0 GPa is 0.86 eV. Furthermore, the detailed analysis of the total and partial density of states is performed to show the specific contribution to the Fermi level.

  4. A DFT study of hydrogen adsorption on Be, Mg and Ca frameworks in erionite zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Fellah, Mehmet Ferdi, E-mail: mferdi.fellah@btu.edu.tr

    2017-02-01

    Highlights: • Mg-ERI and Ca-ERI clusters have much lower chemical potential and hardness. • Adsorption enthalpies for Mg- and Ca-ERI are importantly greater than the liquefaction enthalpy of hydrogen. • Mg-ERI and Ca-ERI clusters have much HOMO-LUMO gap indicating higher reactivity. • Ca- and Mg-ERI are potential cryoadsorbent materials for hydrogen storage. - Abstract: The molecular hydrogen adsorption was investigated on additional frameworks with earth alkaline metal atoms (Be, Mg and Ca) in 24T ERI zeolite cluster model by means of Density Functional Theory study. HOMO and LUMO energy values, chemical potential, chemical hardness, electronegativity, adsorption energy and adsorption enthalpy values have been calculated in this study. Mg-ERI and Ca-ERI clusters have much lower chemical potentials with much lower adsorption energy values when compared to the value of Be-ERI cluster. Additionally, they are softer than Be-ERI cluster with respect to their lower chemical hardness values. Hydrogen adsorption enthalpy values were computed as −3.6 and −3.9 kJ/mol on Mg-ERI and Ca-ERI clusters, respectively. These adsorption enthalpy values are significantly larger than the enthalpy value of liquefaction for hydrogen molecule. This consequently specifies that Mg-ERI and Ca-ERI zeolite structures which have higher chemical reactivity appear to be a promising candidate cryoadsorbent for hydrogen storage.

  5. Naloxone injections into CA3 disrupt pattern completion associated with relapse from cocaine seeking

    Science.gov (United States)

    Kirk, Ryan A.; Clark, Jascha K.; Moore, Angela; Keefe, Kristen

    2016-01-01

    The goal of the present research was to assess the degree to which a pattern completion process operates in cue-induced relapse to cocaine-seeking behavior. Using a novel cue-preference version of the place preference task, rats were administered cocaine or saline, which resulted in a preference for the cocaine-paired cues. After 21 days of abstinence and prior to the preference test, for one group, PBS or naloxone was injected into the CA3 subregion of the hippocampus and for a second group, saline or naloxone was injected systemically. The results indicated that infusions of naloxone into CA3 or systemic injections produced a marked disruption for one and two cues, but had minimal disruptive effect for three or four cues, suggesting that naloxone injections disrupt CA3 function and trigger a deficit in a pattern completion process. Thus, it appears that cue-based activation of the dorsal CA3 might be a critical trigger via a pattern completion process. Based on additional analyses it appears that there is a disruption primarily for object touches for one cue naloxone injections into the CA3 or systemic injections, but no effect on time (spatial context). PMID:26815290

  6. Efficacy of the chelating agent CaEDTA in reversing lead-induced changes in behavior.

    Science.gov (United States)

    Cory-Slechta, D A; Weiss, B

    1989-01-01

    The chelating agent CaEDTA has been reported to reverse the deficits in intellectual function and performance associated with Pb (lead) exposure in children. However, such studies have not included rigorous controls for the intervention procedures per se. The experiments reported here examined reversibility of performance changes in a rat model based on behavior sensitive to low-level Pb exposure. Rats were exposed to 50 ppm sodium or Pb acetate in drinking water from weaning. Performance maintained under a Fixed-Interval schedule of food reinforcement began at 55 days of age. Following the onset of the characteristic increase in short interresponse times (IRTs) associated with low-level Pb exposure after 35 experimental sessions, Pb treatment was terminated. Animals within both the control and Pb groups were then matched on the basis of performance indices and injected daily for 5 days with either saline, 75 mg/kg or 150 mg/kg CaEDTA. Subsequent changes in F1 performance were monitored for 35-60 sessions. No consistent effects of CaEDTA were detected in control animals. CaEDTA treatment failed to reverse the behavioral effects in Pb-exposed animals. If anything, it tended to further increase the proportion of short IRTs. These data suggest that better controlled clinical studies are warranted to evaluate the efficacy of CaEDTA in reversing Pb-induced behavioral effects before its application for these purposes becomes widespread.

  7. The problem of budgetary deficit in modern economies

    Directory of Open Access Journals (Sweden)

    Stanulović Milana

    2017-01-01

    Full Text Available A surplus of expenditure over revenues in the government budget is called a budgetary deficit. Budgetary deficit, in itself, is not a negative thing. If the budgetary deficit allows full employment and helps reaching economic policy goals, there is full understanding for having a budgetary deficit. Budgetary deficit of the Republic of Serbia has shown an increasing tendency in the period 2005-2016. After this period, budgetary deficit has started to decrease as a result of fiscal consolidation measures. Besides avoiding the negative consequences of a budgetary deficit, Serbia has to maintain its budgetary deficit at a level below 3% of GDP, because that is a requirement for joining the European Union. This also applies to countries which are already members of the EU, but they have the right to short term deviations during the economic crisis. The European Union uses these rules to maintain fiscal discipline. By comparing budgetary deficits of the developed and developing countries, we can see a big difference in levels of deficits. Developed countries have higher deficits in the first years of economic recession, while the developing countries' budgets show economic crisis consequences in the subsequent years. The reasons for that lie in crisis overflow channels, thanks to which the developed countries were the first to experience crisis, and only later it affected the developing countries, too.

  8. Brain neurodevelopmental markers related to the deficit subtype of schizophrenia.

    Science.gov (United States)

    Takahashi, Tsutomu; Takayanagi, Yoichiro; Nishikawa, Yumiko; Nakamura, Mihoko; Komori, Yuko; Furuichi, Atsushi; Kido, Mikio; Sasabayashi, Daiki; Noguchi, Kyo; Suzuki, Michio

    2017-08-30

    Deficit schizophrenia is a homogeneous subtype characterized by a trait-like feature of primary and prominent negative symptoms, but the etiologic factors related to this specific subtype remain largely unknown. This magnetic resonance imaging study aimed to examine gross brain morphology that probably reflects early neurodevelopment in 38 patients with deficit schizophrenia, 37 patients with non-deficit schizophrenia, and 59 healthy controls. Potential brain neurodevelopmental markers investigated in this study were the adhesio interthalamica (AI), cavum septi pellucidi (CSP), and surface morphology (i.e., olfactory sulcus depth, sulcogyral pattern, and number of orbital sulci) of the orbitofrontal cortex (OFC). The subtype classification of schizophrenia patients was based on the score of Proxy for the Deficit Syndrome. The deficit schizophrenia group had a significantly shorter AI compared with the non-deficit group and controls. The deficit group, but not the non-deficit group, was also characterized by an altered distribution of the OFC sulcogyral pattern, as well as fewer posterior orbital sulcus compared with controls. Other neurodevelopmental markers did not differentiate the deficit and non-deficit subgroups. These results suggest that the deficit subtype of schizophrenia and its clinical manifestation may be at least partly related to prominent neurodevelopmental pathology. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  9. Ca2+/cation antiporters (CaCA: Identification, characterization and expression profiling in bread wheat (Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Mehak Taneja

    2016-11-01

    Full Text Available The Ca2+/cation antiporters (CaCA superfamily proteins play vital function in Ca2+ ion homeostasis, which is an important event during development and defense response. Molecular characterization of these proteins has been performed in certain plants, but they are still not characterized in Triticum aestivum (bread wheat. Herein, we identified thirty four TaCaCA superfamily proteins, which were classified into TaCAX, TaCCX, TaNCL and TaMHX protein families based on their structural organization and evolutionary relation with earlier reported proteins. Since the T. aestivum comprises an allohexaploid genome, TaCaCA genes were derived from each A, B and D subgenome and homeologous chromosome (HC, except chromosome-group 1. Majority of genes were derived from more than one HCs in each family that were considered as homeologous genes (HGs due to their high similarity with each other. These HGs showed comparable gene and protein structures in terms of exon/intron organization and domain architecture. Majority of TaCaCA proteins comprised two Na_Ca_ex domains. However, TaNCLs consisted of an additional EF-hand domain with calcium binding motifs. Each TaCaCA protein family consisted of about ten transmembrane and two α-repeat regions with specifically conserved signature motifs except TaNCL, which had single α-repeat. Variable expression of most of the TaCaCA genes during various developmental stages suggested their specified role in development. However, constitutively high expression of a few genes like TaCAX1-A and TaNCL1-B indicated their role throughout the plant growth and development. The modulated expression of certain genes during biotic (fungal infections and abiotic stresses (heat, drought, salt suggested their role in stress response. Majority of TaCCX and TaNCL family genes were found highly affected during various abiotic stresses. However the role of individual gene needs to be established. The present study unfolded the opportunity

  10. Ca2+/Cation Antiporters (CaCA): Identification, Characterization and Expression Profiling in Bread Wheat (Triticum aestivum L.).

    Science.gov (United States)

    Taneja, Mehak; Tyagi, Shivi; Sharma, Shailesh; Upadhyay, Santosh Kumar

    2016-01-01

    The Ca 2+ /cation antiporters (CaCA) superfamily proteins play vital function in Ca 2+ ion homeostasis, which is an important event during development and defense response. Molecular characterization of these proteins has been performed in certain plants, but they are still not characterized in Triticum aestivum (bread wheat). Herein, we identified 34 TaCaCA superfamily proteins, which were classified into TaCAX, TaCCX, TaNCL, and TaMHX protein families based on their structural organization and evolutionary relation with earlier reported proteins. Since the T. aestivum comprises an allohexaploid genome, TaCaCA genes were derived from each A, B, and D subgenome and homeologous chromosome (HC), except chromosome-group 1. Majority of genes were derived from more than one HCs in each family that were considered as homeologous genes (HGs) due to their high similarity with each other. These HGs showed comparable gene and protein structures in terms of exon/intron organization and domain architecture. Majority of TaCaCA proteins comprised two Na_Ca_ex domains. However, TaNCLs consisted of an additional EF-hand domain with calcium binding motifs. Each TaCaCA protein family consisted of about 10 transmembrane and two α-repeat regions with specifically conserved signature motifs except TaNCL, which had single α-repeat. Variable expression of most of the TaCaCA genes during various developmental stages suggested their specified role in development. However, constitutively high expression of a few genes like TaCAX1-A and TaNCL1-B indicated their role throughout the plant growth and development. The modulated expression of certain genes during biotic (fungal infections) and abiotic stresses (heat, drought, salt) suggested their role in stress response. Majority of TaCCX and TaNCL family genes were found highly affected during various abiotic stresses. However, the role of individual gene needs to be established. The present study unfolded the opportunity for detail

  11. (Solid + liquid) phase equilibria of (Ca(H2PO2)2 + CaCl2 + H2O) and (Ca(H2PO2)2 + NaH2PO2 + H2O) ternary systems at T = 323.15 K

    International Nuclear Information System (INIS)

    Cao, Hong-yu; Zhou, Huan; Bai, Xiao-qin; Ma, Ruo-xin; Tan, Li-na; Wang, Jun-min

    2016-01-01

    Graphical abstract: Solubility diagram of the (Ca(H 2 PO 2 ) 2 + NaH 2 PO 2 + H 2 O) system at T = (323.15 and 298.15) K. - Highlights: • Phase diagrams of Ca 2+ -H 2 PO 2 − -Cl − -H 2 O, Ca 2+ -Na + -H 2 PO 2 − -H 2 O at 323.15 K were obtained. • Incompatible double salt of NaCa(H 2 PO 2 ) 3 in Ca 2+ -Na + -H 2 PO 2 − -H 2 O system was determined. • Density diagram of the corresponding liquid were simultaneously measured. - Abstract: Calcium hypophosphite has been widely used as an anti-corrosive agent, flame retardant, fertilizer, assistant for Ni electroless plating, and animal nutritional supplement. High purity calcium hypophosphite can be synthesized via the replacement reaction of sodium hypophosphite and calcium chloride. In this work, the (solid + liquid) phase equilibria of (Ca(H 2 PO 2 ) 2 + CaCl 2 + H 2 O) and (Ca(H 2 PO 2 ) 2 + NaH 2 PO 2 + H 2 O) ternary systems at T = 323.15 K were studied experimentally via the classical isothermal solubility equilibrium method, and the phase diagrams for these two systems were obtained. It was found that two solid salts of CaCl 2 ·2H 2 O and Ca(H 2 PO 2 ) 2 exist in the (Ca(H 2 PO 2 ) 2 + CaCl 2 + H 2 O) system, and three salts of Ca(H 2 PO 2 ) 2 , NaH 2 PO 2 ·H 2 O and one incompatible double salt, NaCa(H 2 PO 2 ) 3 occur in the (Ca(H 2 PO 2 ) 2 + NaH 2 PO 2 + H 2 O) system.

  12. On density forecast evaluation

    NARCIS (Netherlands)

    Diks, C.

    2008-01-01

    Traditionally, probability integral transforms (PITs) have been popular means for evaluating density forecasts. For an ideal density forecast, the PITs should be uniformly distributed on the unit interval and independent. However, this is only a necessary condition, and not a sufficient one, as

  13. Measurements of natural 41Ca concentrations

    International Nuclear Information System (INIS)

    Steinhof, A.

    1989-05-01

    Atomic mass spectroscopic examinations on 41 Ca were carried out in the UNILAC accelerator. A sensitivity of about 10 -15 was achieved. This would allow the measurement of present natural 41 Ca concentrations as soon as the problem of the transmission determination is solved. In this respect suggestions were worked out and their feasibility discussed. The detection of 41 Ca-ions is especially free of background when high UNILAC-energies are applied. An estimation showed a background level corresponding with a 41 Ca concentration of less then 10 -17 referred to 40 Ca. Besides an independent concept for the electromagnetic concentration of 41 Ca with variable concentration factors was developed. After being concentrated up to 50 respectively 25 times the initial concentration in the GSI mass separator, the 41 Ca concentration of three recent deer bones found in the Odenwald was measured by atomic mass spectroscopy in the 14UD-Pelletron Tandem in Rehovot (Israel). The measured 41 Ca concentrations ranged between 10 -14 to 10 -13 with consideration of the concentration factor. A theoretical study of the 41 Ca production in the earth's surface based on cosmic radiation illustrates the influence of trace elements on the neutron flux and thus on the 41 Ca production. This influence might be a possible explanation for the observed amplitude of variation of the 41 Ca concentration in recent bones which are of decisive importance for the feasibility of 41 Ca-related dating. In this work a method is suggested that does not depend on the amplitude of variation mentioned above and which would allow the determination of the erosion rate of rocks by its 41 Ca concentrations. (orig./HP) [de

  14. Bax regulates neuronal Ca2+ homeostasis.

    Science.gov (United States)

    D'Orsi, Beatrice; Kilbride, Seán M; Chen, Gang; Perez Alvarez, Sergio; Bonner, Helena P; Pfeiffer, Shona; Plesnila, Nikolaus; Engel, Tobias; Henshall, David C; Düssmann, Heiko; Prehn, Jochen H M

    2015-01-28

    Excessive Ca(2+) entry during glutamate receptor overactivation ("excitotoxicity") induces acute or delayed neuronal death. We report here that deficiency in bax exerted broad neuroprotection against excitotoxic injury and oxygen/glucose deprivation in mouse neocortical neuron cultures and reduced infarct size, necrotic injury, and cerebral edema formation after middle cerebral artery occlusion in mice. Neuronal Ca(2+) and mitochondrial membrane potential (Δψm) analysis during excitotoxic injury revealed that bax-deficient neurons showed significantly reduced Ca(2+) transients during the NMDA excitation period and did not exhibit the deregulation of Δψm that was observed in their wild-type (WT) counterparts. Reintroduction of bax or a bax mutant incapable of proapoptotic oligomerization equally restored neuronal Ca(2+) dynamics during NMDA excitation, suggesting that Bax controlled Ca(2+) signaling independently of its role in apoptosis execution. Quantitative confocal imaging of intracellular ATP or mitochondrial Ca(2+) levels using FRET-based sensors indicated that the effects of bax deficiency on Ca(2+) handling were not due to enhanced cellular bioenergetics or increased Ca(2+) uptake into mitochondria. We also observed that mitochondria isolated from WT or bax-deficient cells similarly underwent Ca(2+)-induced permeability transition. However, when Ca(2+) uptake into the sarco/endoplasmic reticulum was blocked with the Ca(2+)-ATPase inhibitor thapsigargin, bax-deficient neurons showed strongly elevated cytosolic Ca(2+) levels during NMDA excitation, suggesting that the ability of Bax to support dynamic ER Ca(2+) handling is critical for cell death signaling during periods of neuronal overexcitation. Copyright © 2015 the authors 0270-6474/15/351706-17$15.00/0.

  15. Plasticity in stomatal size and density of potato leaves under different irrigation and phosphorus regimes.

    Science.gov (United States)

    Sun, Yanqi; Yan, Fei; Cui, Xiaoyong; Liu, Fulai

    2014-09-01

    The morphological features of stomata including their size and density could be modulated by environmental cues; however, the underlying mechanisms remain largely elusive. Here, the effect of different irrigation and phosphorus (P) regimes on stomatal size (SS) and stomatal density (SD) of potato leaves was investigated. The plants were grown in split-root pots under two P fertilization rates (viz., 0 and 100mgkg(-1) soil, denoted as P0 and P1, respectively) and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation regimes. Results showed that SS and SD were unresponsive to P but significantly affected by the irrigation treatment. FI plants had the largest SS, followed by DI, and PRD the smallest; and the reverse was the case for SD. Compared to FI and DI, PRD plants had significantly lower values of specific leaf area (SLA) and leaf carbon isotope discrimination (Δ(13)C) under P0. Midday leaf water potential (Ψleaf) and stomatal conductance (gs) was similar for DI and PRD, which was significantly lower than that of FI. Leaf contents of C, N, K, Ca and Mg were higher in PRD than in DI plants, particularly under P0. When analyzed across the three irrigation regimes, it was found that the P1 plants had significantly higher leaf contents of P and Mg, but significantly lower leaf K content compared to the P0 plants. Linear correlation analyses revealed that SS was positively correlated with Ψleaf and Δ(13)C; whereas SD was negatively correlated with Ψleaf, Δ(13)C and SLA, and positively correlated with leaf C, N and Ca contents. And gs was positively correlated with SS but negatively correlated with SD. Collectively, under low P level, the smaller and denser stomata in PRD plants may bring about a more efficient stomatal control over gas exchange, hereby potentially enhance water-use efficiency as exemplified by the lowered leaf Δ(13)C under fluctuating soil moisture conditions. Copyright © 2014 Elsevier GmbH. All rights reserved.

  16. Learning Grasp Affordance Densities

    DEFF Research Database (Denmark)

    Detry, Renaud; Kraft, Dirk; Kroemer, Oliver

    2011-01-01

    and relies on kernel density estimation to provide a continuous model. Grasp densities are learned and refined from exploration, by letting a robot “play” with an object in a sequence of graspand-drop actions: The robot uses visual cues to generate a set of grasp hypotheses; it then executes......We address the issue of learning and representing object grasp affordance models. We model grasp affordances with continuous probability density functions (grasp densities) which link object-relative grasp poses to their success probability. The underlying function representation is nonparametric...... these and records their outcomes. When a satisfactory number of grasp data is available, an importance-sampling algorithm turns these into a grasp density. We evaluate our method in a largely autonomous learning experiment run on three objects of distinct shapes. The experiment shows how learning increases success...

  17. A SPECT study in internal carotid artery occlusion: Discrepancies between flow image and neurologic deficits

    International Nuclear Information System (INIS)

    Moriwaki, H.; Hougaku, H.; Matsuda, I.; Kusunoki, M.; Shirai, J.

    1989-01-01

    A SPECT (single photon emission computed tomography) study in internal carotid artery (ICA) occlusion was performed in 6 patients. The validity of iodoamphetamine (IMP) SPECT study in the evaluation of cerebral blood flow (CBF) or neurologic function is still controversial. In this study, the authors showed several cases in whom SPECT images of brain were not compatible with their neurologic deficits. In 2 typical cases, a large low-density area was observed in the non-dominant hemisphere in computed tomography (CT) scan, but no apparent motor-sensory deficits in left limbs were present. In these patients, SPECT study also revealed flow reduction in the affected side of the brain. So there was a possibility that an IMP brain image could not always reflect CBF, which maintains neurologic function of the brain

  18. FMR1 gene expansion and scans without evidence of dopaminergic deficits in parkinsonism patients.

    Science.gov (United States)

    Hall, D A; Jennings, D; Seibyl, J; Tassone, F; Marek, K

    2010-11-01

    To determine if patients with parkinsonism and fragile X mental retardation 1 (FMR1) gene expansions have a striatal dopamine deficit similar to Parkinson disease (PD) patients. The authors studied three patients with parkinsonism carrying small expansions in the FMR1 gene (41-60 CGG) with [(123)I]β-CIT SPECT imaging. The patients responded to dopaminergic medications, but had preserved dopamine transporter density. These results suggest that parkinsonism associated with smaller FMR1 expansions may be related to mechanisms other than pre-synaptic dopaminergic changes and may represent a potential explanation for at least some parkinsonian cases with scans without evidence of dopaminergic deficits (SWEDD). Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Molecular, physiological and biochemical responses of Theobroma cacao L. genotypes to soil water deficit.

    Science.gov (United States)

    Santos, Ivanildes C Dos; Almeida, Alex-Alan Furtado de; Anhert, Dário; Conceição, Alessandro S da; Pirovani, Carlos P; Pires, José L; Valle, Raúl René; Baligar, Virupax C

    2014-01-01

    Six months-old seminal plants of 36 cacao genotypes grown under greenhouse conditions were subjected to two soil water regimes (control and drought) to assess, the effects of water deficit on growth, chemical composition and oxidative stress. In the control, soil moisture was maintained near field capacity with leaf water potentials (ΨWL) ranging from -0.1 to -0.5 MPa. In the drought treatment, the soil moisture was reduced gradually by withholding additional water until ΨWL reached values of between -2.0 to -2.5 MPa. The tolerant genotypes PS-1319, MO-20 and MA-15 recorded significant increases in guaiacol peroxidase activity reflecting a more efficient antioxidant metabolism. In relation to drought tolerance, the most important variables in the distinguishing contrasting groups were: total leaf area per plant; leaf, stem and total dry biomass; relative growth rate; plant shoot biomass and leaf content of N, Ca, and Mg. From the results of these analyses, six genotypes were selected with contrasting characteristics for tolerance to soil water deficit [CC-40, C. SUL-4 and SIC-2 (non-tolerant) and MA-15, MO-20, and PA-13 (tolerant)] for further assessment of the expression of genes NCED5, PP2C, psbA and psbO to water deficit. Increased expression of NCED5, PP2C, psbA and psbO genes were found for non-tolerant genotypes, while in the majority of tolerant genotypes there was repression of these genes, with the exception of PA-13 that showed an increased expression of psbA. Mutivariate analysis showed that growth variables, leaf and total dry biomass, relative growth rate as well as Mg content of the leaves were the most important factor in the classification of the genotypes as tolerant, moderately tolerant and sensitive to water deficit. Therefore these variables are reliable plant traits in the selection of plants tolerant to drought.

  20. Comparative study of anisotropic superconductivity in CaAlSi and CaGaSi

    International Nuclear Information System (INIS)

    Tamegai, T.; Uozato, K.; Kasahara, S.; Nakagawa, T.; Tokunaga, M.

    2005-01-01

    In order to get some insight into the origin of the anomalous angular dependence of H c2 in a layered intermetallic compound CaAlSi, electronic, superconducting, and structural properties are compared between CaAlSi and CaGaSi. The angular dependence of H c2 in CaGaSi is well described by the anisotropic GL model. Parallel to this finding, the pronounced lattice modulation accompanying the superstructure along the c-axis in CaAlSi is absent in CaGaSi. A relatively large specific heat jump at the superconducting transition in CaAlSi compared with CaGaSi indicates the presence of strong electron-phonon coupling in CaAlSi, which may cause the superstructure and the anomalous angular dependence of H c2

  1. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

    Directory of Open Access Journals (Sweden)

    Xiao-Chen Li

    Full Text Available Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+ homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+ current (I(Ca was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca did not compromise the Ca(2+-induced Ca(2+ release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca. Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+ removal were more rapid in ground squirrels. Ca(2+ sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca threshold, low SR Ca(2+ leak and rapid cytosolic Ca(2+ clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+ homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+ overload-related heart diseases.

  2. First-Principles Study on the Adsorption Properties of Transition-Metal Atoms on CaO(001) Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Byung Deok [University of Seoul, Seoul (Korea, Republic of); Jang, Young-Rok [Incheon National University, Incheon (Korea, Republic of)

    2017-03-15

    By using first-principles electronic-structure calculations based on the density functional theory, we systematically investigated the adsorption properties of transition-metal (TM) adatoms on CaO(001) surfaces. Optimized adsorption structures and energetics of TM adatoms on CaO(001) are reported for various adsorption structures. The results are different from those of TM adatoms on MgO(001). Concomitantly, this suggests different dynamical properties of TM adatoms on CaO(001) surfaces as compared with TM adatoms on MgO(001) surfaces. Also performed was an analysis of the electronic structures of the TM adatoms on CaO(001) by using the energy positions of the adsorbate states with respect to the valence band maximum of CaO. The results are discussed in connection with the charge states of the TM adatoms on doped CaO(001).

  3. Executive and attentional contributions to Theory of Mind deficit in attention deficit/hyperactivity disorder (ADHD).

    Science.gov (United States)

    Mary, Alison; Slama, Hichem; Mousty, Philippe; Massat, Isabelle; Capiau, Tatiana; Drabs, Virginie; Peigneux, Philippe

    2016-01-01

    Attention deficit/hyperactivity disorder (ADHD) in children has been associated with attentional and executive problems, but also with socioemotional difficulties possibly associated with deficits in Theory of Mind (ToM). Socioemotional problems in ADHD are associated with more negative prognoses, notably interpersonal, educational problems, and an increased risk of developing other psychiatric disorders that emphasize the need to clarify the nature of their ToM deficits. In this study, we hypothesized that ToM dysfunction in children with ADHD is largely attributable to their attentional and/or executive deficits. Thirty-one children with ADHD (8-12 years, IQ > 85) and 31 typically developing (TD) children were assessed using executive functions (inhibition, planning, and flexibility) and attentional tasks, as well as two advanced ToM tasks (Reading the Mind in the Eyes and Faux Pas) involving different levels of executive control. Children with ADHD performed more poorly than TD children in attentional, executive function, and ToM tasks. Linear regression analyses conducted in the ADHD group indicated that inhibition scores predicted performance on the "Faux Pas" task the best, while attention scores were the best for predicting performance on the Reading the Mind in the Eyes task. When controlled for inhibition and attentional variables, ToM performance in children with ADHD was actually similar to TD children. Contrarily, controlling for ToM scores did not normalize performance for inhibition and attentional tasks in children with ADHD. This unidirectional relationship suggests that deficits in the EF and attentional domains are responsible for ToM deficits in ADHD, which therefore may contribute to their socioemotional difficulties.

  4. The Properties of Sintered Calcium Phosphate with [Ca]/[P] = 1.50

    Directory of Open Access Journals (Sweden)

    Moo-Chin Wang

    2012-10-01

    Full Text Available In order to obtain the properties of the sintered as-dried calcium phosphate with [Ca]/[P] = 1.50, the characteristics of sintered pellets have been investigated using X-ray diffraction (XRD, inductively coupled plasma-mass spectrometry (ICP-MS, Fourier-transform infrared (FT-IR spectra, Vickers hardness indentation and scanning electron microscopy (SEM. When the pellet samples were sintered between 700 °C and 1200 °C for 4 h, the hydroxyapatite (Ca10(PO46(OH2, HA still maintained the major phase, accompanied with the rhenanite (NaCaPO4 as the secondary phase and β-tricalcium phosphate (β-Ca3(PO42, β-TCP as the minor phases. In addition, the HA partially transformed to α-tricalcium phosphate (α-Ca3(PO42, α-TCP and tetracalcium phosphate (Ca4(PO42O, TTCP, when the pellet samples were sintered at 1300 °C and 1400 °C, respectively, for 4 h. The maximum density and Vickers Hardness (HV of sintered pellet samples were 2.85 g/cm3 (90.18% theoretical density (T.D. and 407, which appeared at 1200 °C and 900 °C, respectively.

  5. Current density tensors

    Science.gov (United States)

    Lazzeretti, Paolo

    2018-04-01

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

  6. Estradiol pretreatment ameliorates impaired synaptic plasticity at synapses of insulted CA1 neurons after transient global ischemia

    Science.gov (United States)

    Takeuchi, Koichi; Yang, Yupeng; Takayasu, Yukihiro; Gertner, Michael; Hwang, Jee-Yeon; Aromolaran, Kelly; Bennett, Michael V.L.; Zukin, R. Suzanne

    2015-01-01

    Global ischemia in humans or induced experimentally in animals causes selective and delayed neuronal death in pyramidal neurons of the hippocampal CA1. The ovarian hormone estradiol administered before or immediately after insult affords histological protection in experimental models of focal and global ischemia and ameliorates the cognitive deficits associated with ischemic cell death. However, the impact of estradiol on the functional integrity of Schaffer collateral to CA1 (Sch-CA1) pyramidal cell synapses following global ischemia is not clear. Here we show that long term estradiol treatment initiated 14 days prior to global ischemia in ovariectomized female rats acts via the IGF-1 receptor to protect the functional integrity of CA1 neurons. Global ischemia impairs basal synaptic transmission, assessed by the input/output relation at Sch-CA1 synapses, and NMDA receptor (NMDAR)-dependent long term potentiation (LTP), assessed at 3 days after surgery. Presynaptic function, assessed by fiber volley and paired pulse facilitation, is unchanged. To our knowledge, our results are the first to demonstrate that estradiol at near physiological concentrations enhances basal excitatory synaptic transmission and ameliorates deficits in LTP at synapses onto CA1 neurons in a clinically-relevant model of global ischemia. Estradiol-induced rescue of LTP requires the IGF-1 receptor, but not the classical estrogen receptors (ER)-α or β. These findings support a model whereby estradiol acts via the IGF-1 receptor to maintain the functional integrity of hippocampal CA1 synapses in the face of global ischemia. PMID:25463028

  7. Study of electronic and structural properties of CaS

    International Nuclear Information System (INIS)

    Mirfenderski, M.; Akbarzdeh, H.; Mokhtari, A.

    2003-01-01

    The electronic and structural properties of CaS are calculated using full potential linearized augmented plane wave method within the local density approximation and generalized gradient approximation for the exchange -correlation energy. For both structures, NaCl structure (B1) and CsCl structure (B2), the obtained values for lattice parameters, bulk modulus and its pressure derivative and transition pressure are in reasonable agreement with the experimental values. For electronic properties, the obtained value for band gap is smaller than the experimental value as well as other calculated results based on density functional theory. Engel and Vosko calculated an exchange potential for some atoms within the so-called optimize-potential model and then used the virial relation and constructed a new exchange-correlation functional. We used that functional and obtained reasonable results for band gap. Finally we investigated the possibility for a third phase ( Zinc Blend structure) for this crystal

  8. Widespread auditory deficits in tune deafness.

    Science.gov (United States)

    Jones, Jennifer L; Zalewski, Christopher; Brewer, Carmen; Lucker, Jay; Drayna, Dennis

    2009-02-01

    The goal of this study was to investigate auditory function in individuals with deficits in musical pitch perception. We hypothesized that such individuals have deficits in nonspeech areas of auditory processing. We screened 865 randomly selected individuals to identify those who scored poorly on the Distorted Tunes test (DTT), a measure of musical pitch recognition ability. Those who scored poorly were given a comprehensive audiologic examination, and those with hearing loss or other confounding audiologic factors were excluded from further testing. Thirty-five individuals with tune deafness constituted the experimental group. Thirty-four individuals with normal hearing and normal DTT scores, matched for age, gender, handedness, and education, and without overt or reported psychiatric disorders made up the normal control group. Individual and group performance for pure-tone frequency discrimination at 1000 Hz was determined by measuring the difference limen for frequency (DLF). Auditory processing abilities were assessed using tests of pitch pattern recognition, duration pattern recognition, and auditory gap detection. In addition, we evaluated both attention and short- and long-term memory as variables that might influence performance on our experimental measures. Differences between groups were evaluated statistically using Wilcoxon nonparametric tests and t-tests as appropriate. The DLF at 1000 Hz in the group with tune deafness was significantly larger than that of the normal control group. However, approximately one-third of participants with tune deafness had DLFs within the range of performance observed in the control group. Many individuals with tune deafness also displayed a high degree of variability in their intertrial frequency discrimination performance that could not be explained by deficits in memory or attention. Pitch and duration pattern discrimination and auditory gap-detection ability were significantly poorer in the group with tune deafness

  9. Neurocognitive impairment in the deficit subtype of schizophrenia.

    Science.gov (United States)

    Fervaha, Gagan; Agid, Ofer; Foussias, George; Siddiqui, Ishraq; Takeuchi, Hiroyoshi; Remington, Gary

    2016-08-01

    Schizophrenia is a heterogeneous disorder characterized by numerous diverse signs and symptoms. Individuals with prominent, persistent, and idiopathic negative symptoms are thought to encompass a distinct subtype of schizophrenia. Previous work, including studies involving neuropsychological evaluations, has supported this position. The present study sought to further examine whether deficit patients are cognitively distinct from non-deficit patients with schizophrenia. A comprehensive neurocognitive battery including tests of verbal memory, vigilance, processing speed, reasoning, and working memory was administered to 657 patients with schizophrenia. Of these, 144 (22 %) patients were classified as deficit patients using a proxy identification method based on severity, persistence over time, and possible secondary sources (e.g., depression) of negative symptoms. Deficit patients with schizophrenia performed worse on all tests of cognition relative to non-deficit patients. These patients were characterized by a generalized cognitive impairment on the order of about 0.4 standard deviations below that of non-deficit patients. However, when comparing deficit patients to non-deficit patients who also present with negative symptoms, albeit not enduring or primary, no group differences in cognitive performance were found. Furthermore, a discriminant function analysis classifying patients into deficit/non-deficit groups based on cognitive scores demonstrated only 62.3 % accuracy, meaning over one-third of individuals were misclassified. The deficit subtype of schizophrenia is not markedly distinct from non-deficit schizophrenia in terms of neurocognitive performance. While deficit patients tend to have poorer performance on cognitive tests, the magnitude of this effect is relatively modest, translating to over 70 % overlap in scores between groups.

  10. Environment, migration and the European demographic deficit

    International Nuclear Information System (INIS)

    Harper, Sarah

    2012-01-01

    Many countries in the more developed world, and some in the less developed, are facing new economic and social pressures associated with the ageing of their populations. Europe, in particular, is forecast to have a demographic deficit, which may be alleviated by in-migration to the region. However, several commentators have proposed that Europe will not be able to successfully compete with other regions, in particular Asia, in the coming years for the skills it will require. This letter explores these themes, arguing that climate change will increase the attractiveness of Europe as a destination of economic choice for future skilled workers, to the detriment of more environmentally challenged regions. (letter)

  11. Attention-deficit/hyperactivity disorder (ADHD)

    DEFF Research Database (Denmark)

    Dalsgaard, S.

    2013-01-01

    The proposed revision of the diagnostic criteria in DSM-5 for attention-deficit/hyperactivity disorder (ADHD) will not fundamentally change the concept of ADHD. This is mainly due to the fact that, DSM-5 will retain the exact DSM-IV wording of all 18 symptoms, but will add new examples that make...... the criteria more appropriate for children, adolescents and adults. The age of onset will also be changed from 7 to 12 years, the subtyping of the disorder will change, and pervasive developmental disorders will no longer be an exclusion criterion. Although the main concept is unchanged, the suggested changes...

  12. Environment, migration and the European demographic deficit

    Science.gov (United States)

    Harper, Sarah

    2012-03-01

    Many countries in the more developed world, and some in the less developed, are facing new economic and social pressures associated with the ageing of their populations. Europe, in particular, is forecast to have a demographic deficit, which may be alleviated by in-migration to the region. However, several commentators have proposed that Europe will not be able to successfully compete with other regions, in particular Asia, in the coming years for the skills it will require. This letter explores these themes, arguing that climate change will increase the attractiveness of Europe as a destination of economic choice for future skilled workers, to the detriment of more environmentally challenged regions.

  13. [DMS-5 - attention-deficit/hyperactivity disorder].

    Science.gov (United States)

    Banaschewski, Tobias; Döpfner, Manfred

    2014-07-01

    Modifications to the DSM-5 criteria for the diagnosis of attention-deficit/hyperactivity disorders are described and discussed. The main modifications concern the onset of the disorder, the reduction on the number of criteria fulfilled for a diagnosis in patients aged 17 years or older, and the elimination of autism spectrum disorders as an exclusion criterion for this diagnosis. These changes are mainly welcomed. However, the demanded increase in the age for the latest onset of the disorder may prove to be problematic.

  14. Influence of the Pauli exclusion principle and the polarization of nuclei on the nuclear part of the interaction potential in the 40Ca +40Ca system

    Science.gov (United States)

    Nesterov, V. O.

    2018-06-01

    In the framework of the energy density method with the use of the wave function of the two-center shell model, the influence of the simultaneous account for the Pauli exclusion principle and the monopole and quadrupole polarizations of nuclei on the nuclear part of the potential of their interaction by the example of the 40Ca +40Ca system is considered. The calculations performed in the framework of the adiabatic approximation show that the consideration of the Pauli exclusion principle and the polarization of nuclei, especially the quadrupole one, essentially affects the nucleus-nucleus interaction potential.

  15. Effects of Dopant on the Dielectric Properties of CaZrO3 Ceramic Sintered in a Reducing Atmosphere

    Science.gov (United States)

    Lee, W. S.; Su, C. Y.; Lee, Y. C.; Lin, S. P.; Yang, Tony

    2006-07-01

    In this study, the influence of CaZrO3 doped with three dopants, SiO2, MnO, and Nb2O5, and then sintered in a reducing atmosphere on microstructure, phase formation, and electrical properties is investigated. SiO2 plays the role of sintering aid to enhance the density of CaZrO3 leading to better performance of electrical properties as a function of SiO2 content. MnO, and Nb2O5 were incorporated into the Zr-site of CaZrO3 to make stoichometric CaZrO3 into non-stoichiometric CaZrO3 with Zr excess resulting in the formation of a second phase, CaZr4O9, which has a lower dielectric constant (13) in comparison with that of the main phase of CaZrO3 (32). Thus, the dielectric constant of CaZrO3 doped with Nb2O5, or MnO is decreased markedly. In addition, Mn+2 incorporated into Zr-sites of CaZrO3 plays the role of acceptor, which compensates for the number of conduction electrons and contributes to better performance of electrical properties such as insulation resistance and \\tanδ. Conversely, Nb+5 incorporated into Zr-sites of CaZrO3 plays the role of donor and provides more conduction electrons, leading to poor performance of electrical properties.

  16. Proton resonance spectroscopy in 40Ca

    International Nuclear Information System (INIS)

    Warthen, B.J.

    1987-01-01

    The differential cross sections for the 39 K(p,p o ) 39 K and 39 K-(p,α o ) 36 Ar reactions have been measured for E p = 1.90 to 4.02 MeV at laboratory angles θ = 90 degree, 108 degree, 150 degree and 165 degree. Data were taken with the Triangle Universities Nuclear Laboratory (TUNL) KN Van de Graaff accelerator and the associated high resolution system. The targets consisted of 1-2 μg/cm 2 of potassium carbonate (K 2 CO 3 ), enriched to 99.97% 39 K, evaporated onto gold coated carbon backings. Excitation functions were measured in proton energy steps varying from 100 to 400 3V. The energy region studied corresponds to an excitation energy range in the 40 Ca nucleus of E x = 10.2 to 12.3 MeV. A multi-level multi-channel R-matrix based computer code was used to fit the experimental excitation functions. Resonance parameters obtained include resonance energy, spin, parity, partial widths, and channel spin and orbital angular momentum mixing ratios. Of the 248 resonances observed in the proton channel, 148 were also observed in the alpha channel. A fit to the observed level density yielded a nuclear temperature of 1.5 MeV. The data were compared with predictions of statistical theories of energy levels for both level spacing and reduced width distributions. The alpha reduced widths agree with the Porter-Thomas distribution and suggest that only 5-10% of the states with alpha widths were not observed. The summed strength in each of the alpha channels represents a significant fraction of the Wigner limit for these channels. The proton channels, on the other hand, generally have much smaller fractions. The two proton s-wave strength functions are equal and thus show no evidence for spin-exchange forces in the nucleon-nucleus interaction

  17. Electron scattering by nuclei and transition charge densities

    International Nuclear Information System (INIS)

    Gul'karov, I.S.

    1988-01-01

    Transition charge densities for states of electric type, for nuclei with A≤40--50 as obtained from data on inelastic electron scattering, are studied. The formalism of electroexcitation of nuclei is considered, together with various models (macroscopic and microscopic) used to calculate form factors, transition charge densities, and the moments of these densities: B(Eλ) and R/sub λ/ . The macroscopic models are derived microscopically, and it is shown that the model-independent sum rules lead to the same transition densities as calculations based on various hydrodynamic models. The sum rules with and without allowance for the Skyrme exchange interaction are discussed. The results of the calculations are compared with the experimental form factors of electron scattering by nuclei from 12 C to 48 Ca with excitation in them of normal-parity states with I/sup π/ = 0 + , 1 - , 2 + , 3 - , 4 + , 5 - and T = 0. The model-independent transition charge densities for the weakly collectivized excitations differ strongly from the model-dependent densities. The influence of neutrons on the transition charge densities of the nuclear isotopes 16 /sup ,/ 18 O, 32 /sup ,/ 34 S, and 40 /sup ,/ 48 Ca is considered

  18. Biphasic decay of the Ca transient results from increased sarcoplasmic reticulum Ca leak

    Science.gov (United States)

    Sankaranarayanan, Rajiv; Li, Yatong; Greensmith, David J.; Eisner, David A.

    2016-01-01

    Key points Ca leak from the sarcoplasmic reticulum through the ryanodine receptor (RyR) reduces the amplitude of the Ca transient and slows its rate of decay.In the presence of β‐adrenergic stimulation, RyR‐mediated Ca leak produces a biphasic decay of the Ca transient with a fast early phase and a slow late phase.Two forms of Ca leak have been studied, Ca‐sensitising (induced by caffeine) and non‐sensitising (induced by ryanodine) and both induce biphasic decay of the Ca transient.Only Ca‐sensitising leak can be reversed by traditional RyR inhibitors such as tetracaine.Ca leak can also induce Ca waves. At low levels of leak, waves occur. As leak is increased, first biphasic decay and then slowed monophasic decay is seen. The level of leak has major effects on the shape of the Ca transient. Abstract In heart failure, a reduction in Ca transient amplitude and contractile dysfunction can by caused by Ca leak through the sarcoplasmic reticulum (SR) Ca channel (ryanodine receptor, RyR) and/or decreased activity of the SR Ca ATPase (SERCA). We have characterised the effects of two forms of Ca leak (Ca‐sensitising and non‐sensitising) on calcium cycling and compared with those of SERCA inhibition. We measured [Ca2+]i with fluo‐3 in voltage‐clamped rat ventricular myocytes. Increasing SR leak with either caffeine (to sensitise the RyR to Ca activation) or ryanodine (non‐sensitising) had similar effects to SERCA inhibition: decreased systolic [Ca2+]i, increased diastolic [Ca2+]i and slowed decay. However, in the presence of isoproterenol, leak produced a biphasic decay of the Ca transient in the majority of cells while SERCA inhibition produced monophasic decay. Tetracaine reversed the effects of caffeine but not of ryanodine. When caffeine (1 mmol l−1) was added to a cell which displayed Ca waves, the wave frequency initially increased before waves disappeared and biphasic decay developed. Eventually (at higher caffeine concentrations), the

  19. Cooper pair formation dynamics in Bi2Sr2CaCu2O8+δ

    International Nuclear Information System (INIS)

    Kaindl, R.A.; Carnahan, M.A.; Orenstein, J.; Chemla, D.S.; Oh, S.; Eckstein, J.N.

    2003-01-01

    We utilize ultrafast terahertz pulses to monitor the carrier dynamics in the high-TC superconductor Bi2Sr2CaCu2O8+delta. The temperature, density and time dependence distinctly exposes a bimolecular recombination process of quasiparticles which underlies formation of Cooper pairs

  20. Intrinsic-density functionals

    International Nuclear Information System (INIS)

    Engel, J.

    2007-01-01

    The Hohenberg-Kohn theorem and Kohn-Sham procedure are extended to functionals of the localized intrinsic density of a self-bound system such as a nucleus. After defining the intrinsic-density functional, we modify the usual Kohn-Sham procedure slightly to evaluate the mean-field approximation to the functional, and carefully describe the construction of the leading corrections for a system of fermions in one dimension with a spin-degeneracy equal to the number of particles N. Despite the fact that the corrections are complicated and nonlocal, we are able to construct a local Skyrme-like intrinsic-density functional that, while different from the exact functional, shares with it a minimum value equal to the exact ground-state energy at the exact ground-state intrinsic density, to next-to-leading order in 1/N. We briefly discuss implications for real Skyrme functionals

  1. Density functional theory

    International Nuclear Information System (INIS)

    Das, M.P.

    1984-07-01

    The state of the art of the density functional formalism (DFT) is reviewed. The theory is quantum statistical in nature; its simplest version is the well-known Thomas-Fermi theory. The DFT is a powerful formalism in which one can treat the effect of interactions in inhomogeneous systems. After some introductory material, the DFT is outlined from the two basic theorems, and various generalizations of the theorems appropriate to several physical situations are pointed out. Next, various approximations to the density functionals are presented and some practical schemes, discussed; the approximations include an electron gas of almost constant density and an electron gas of slowly varying density. Then applications of DFT in various diverse areas of physics (atomic systems, plasmas, liquids, nuclear matter) are mentioned, and its strengths and weaknesses are pointed out. In conclusion, more recent developments of DFT are indicated

  2. Low Density Supersonic Decelerators

    Data.gov (United States)

    National Aeronautics and Space Administration — The Low-Density Supersonic Decelerator project will demonstrate the use of inflatable structures and advanced parachutes that operate at supersonic speeds to more...

  3. density functional theory approach

    Indian Academy of Sciences (India)

    YOGESH ERANDE

    2017-07-27

    Jul 27, 2017 ... a key role in all optical switching devices, since their optical properties can be .... optimized in the gas phase using Density Functional Theory. (DFT).39 The ...... The Mediation of Electrostatic Effects by Sol- vents J. Am. Chem.

  4. Bone mineral density test

    Science.gov (United States)

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis - BMD ... need to undress. This scan is the best test to predict your risk of fractures, especially of ...

  5. Density scaling for multiplets

    International Nuclear Information System (INIS)

    Nagy, A

    2011-01-01

    Generalized Kohn-Sham equations are presented for lowest-lying multiplets. The way of treating non-integer particle numbers is coupled with an earlier method of the author. The fundamental quantity of the theory is the subspace density. The Kohn-Sham equations are similar to the conventional Kohn-Sham equations. The difference is that the subspace density is used instead of the density and the Kohn-Sham potential is different for different subspaces. The exchange-correlation functional is studied using density scaling. It is shown that there exists a value of the scaling factor ζ for which the correlation energy disappears. Generalized OPM and Krieger-Li-Iafrate (KLI) methods incorporating correlation are presented. The ζKLI method, being as simple as the original KLI method, is proposed for multiplets.

  6. The Pr and Ca substitution in GdBa2Cu3O7-8

    International Nuclear Information System (INIS)

    Shakeri, H.; Akhavan, M.

    2002-01-01

    The granular Gd 1 -x-zPr x Ca z Ba 2 Cu 3 O 7 -8 (Gd Pr Ca-123) high-temperature cuprate samples with 0.0≤x≤0.3 and 0.0≤z≤0.35 are prepared by standard solid state reaction and characterized by XRD and SEM techniques. The BaCuO 2 and impurity phases are less than 1% in the samples having high levels of Pr and Ca concentrations. The electrical resistivity measurements show a nonlinear reduction in T c (x,z=etc) versus x. Moreover, the T c (z) curve with x=0 is nonlinear and a plateau appears at z≅0.05-0.015. For Pr-Ca-doped samples with a constant concentration of Pr, T c increases with the increase of Ca up to an optimum value of Ca doping and then in decreases. Based on these observations, we suggest that hole filling and hole localization the main effects of Pr ion substitution. The magnetic measurements indicate that the value of H C 1 is in the order of 10 m T. The magnetoresistance measurements have been measured and analyzed. The superconducting transition region is broadened by the application of magnetic field. The experimental data near the on sen of superconductivity are fitted with the Ambegakor and Halperin (A H) phase-slip model. We observe that the A H parameter, γ(H), depends not only on the temperature and the magnetic field, but also on the Pr and Ca ions concentrations. It is observed that the critical current density increases with Ca substitution and decreases with pr substitution in Gd-123 system. We suggest that the pr ion substitution probably enhances the weak link, but the Ca ion acts as flux pinning center in the Gd Pr Ca-123 system

  7. Fission level densities

    International Nuclear Information System (INIS)

    Maslov, V.M.

    1998-01-01

    Fission level densities (or fissioning nucleus level densities at fission saddle deformations) are required for statistical model calculations of actinide fission cross sections. Back-shifted Fermi-Gas Model, Constant Temperature Model and Generalized Superfluid Model (GSM) are widely used for the description of level densities at stable deformations. These models provide approximately identical level density description at excitations close to the neutron binding energy. It is at low excitation energies that they are discrepant, while this energy region is crucial for fission cross section calculations. A drawback of back-shifted Fermi gas model and traditional constant temperature model approaches is that it is difficult to include in a consistent way pair correlations, collective effects and shell effects. Pair, shell and collective properties of nucleus do not reduce just to the renormalization of level density parameter a, but influence the energy dependence of level densities. These effects turn out to be important because they seem to depend upon deformation of either equilibrium or saddle-point. These effects are easily introduced within GSM approach. Fission barriers are another key ingredients involved in the fission cross section calculations. Fission level density and barrier parameters are strongly interdependent. This is the reason for including fission barrier parameters along with the fission level densities in the Starter File. The recommended file is maslov.dat - fission barrier parameters. Recent version of actinide fission barrier data obtained in Obninsk (obninsk.dat) should only be considered as a guide for selection of initial parameters. These data are included in the Starter File, together with the fission barrier parameters recommended by CNDC (beijing.dat), for completeness. (author)

  8. Density-wave oscillations

    International Nuclear Information System (INIS)

    Belblidia, L.A.; Bratianu, C.

    1979-01-01

    Boiling flow in a steam generator, a water-cooled reactor, and other multiphase processes can be subject to instabilities. It appears that the most predominant instabilities are the so-called density-wave oscillations. They can cause difficulties for three main reasons; they may induce burnout; they may cause mechanical vibrations of components; and they create system control problems. A comprehensive review is presented of experimental and theoretical studies concerning density-wave oscillations. (author)

  9. Density of liquid Ytterbium

    International Nuclear Information System (INIS)

    Stankus, S.V.; Basin, A.S.

    1983-01-01

    Results are presented for measurements of the density of metallic ytterbium in the liquid state and at the liquid-solid phase transition. Based on the numerical data obtained, the coefficient of thermal expansion βZ of the liquid and the density discontinuity on melting deltarho/sub m/ are calculated. The magnitudes of βZ and deltarho/sub m/ for the heavy lanthanides are compared

  10. Mechanochemically driven nonequilibrium processes in MNH2-CaH2 systems (M = Li or Na)

    International Nuclear Information System (INIS)

    Dolotko, Oleksandr; Zhang Haiqiao; Li Sa; Jena, Puru; Pecharsky, Vitalij

    2010-01-01

    Mechanochemical transformations of lithium and sodium amides with calcium hydride have been investigated using gas volumetric analysis, X-ray powder diffraction, and residual gas analysis. The overall mechanochemical transformations are equimolar, and they proceed as the following solid state reaction: MNH 2 + CaH 2 → CaNH + MH + H 2 , where M = Li or Na. The transformation kinetics of the lithium containing system is markedly faster compared to the system with sodium. The difference in the rates of solid state transformations, and therefore, in hydrogen release kinetics can be explained by difference in mobility of lithium and sodium atoms. Total energies and enthalpies of formation for different reaction products during the dehydrogenation of CaH 2 -MNH 2 mixtures were calculated using density functional theory. Compared to thermochemical transformations, which proceed in accordance with thermodynamic equilibrium, reactions induced by mechanical energy drive the MNH 2 -CaH 2 systems to nonequilibrium configurations with different final products.

  11. Oxygen chain disorder and compensation by Ca in Y(1-2-3) cuprates

    International Nuclear Information System (INIS)

    Suryanarayanan, R.; Ouhammou, L.; Das, A.; Leelaprute, S.

    1994-01-01

    Several M dopants such as Al, Fe, and Co at the Cu site destroy the superconductivity of YBa 2 Cu 3 O 6+z . However, superconductivity is restored by substituting Ca at the Y site. Arguments are developed to show that the oxygen chain disorder is not the only cause for destroying the superconductivity. A universal relation seems to exist between the net hole density as a result of Ca substitution and Tc. To stabilize the perovskite structure of YSr 2 Cu 3 O 6+z , it is necessary to substitute Cu by certain elements. Examples are given on Ti and Re substitution. Again, Ca cosubstitution increases Tc. Further, the irreversibility line is enhanced by Ca, indicating improved pinning in these materials in spite of the oxygen disorder. 16 refs., 4 figs., 1 tab

  12. Structure, electronic and magnetic properties of Ca-doped chromium oxide studied by the DFT method

    International Nuclear Information System (INIS)

    Maldonado, Frank; Rivera, Richard; Stashans, Arvids

    2012-01-01

    Using first-principles density functional theory calculations within the generalised gradient approximation (GGA) as well as GGA+U method we study Ca-doped α-Cr 2 O 3 crystal. Structural, electronic and magnetic properties due to the singular impurity incorporation have been investigated and discussed in detail. Atomic shifts as well as computed Bader charges on atoms imply the importance of ionic nature in the atomic interactions in chromium oxide. The study improves our knowledge on how the crystalline lattice reacts on the presence of a Ca dopant. According to our research it is found that Ca impurity incorporation produces some local changes upon the electronic band structure of the material without occurrence of local states within the band-gap. It is found that Ca incorporation produces change in magnetic behaviour of the crystal: it becomes ferromagnetic.

  13. Structure, electronic and magnetic properties of Ca-doped chromium oxide studied by the DFT method

    Energy Technology Data Exchange (ETDEWEB)

    Maldonado, Frank; Rivera, Richard [Grupo de Fisicoquimica de Materiales, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Stashans, Arvids, E-mail: arvids@utpl.edu.ec [Grupo de Fisicoquimica de Materiales, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador)

    2012-04-15

    Using first-principles density functional theory calculations within the generalised gradient approximation (GGA) as well as GGA+U method we study Ca-doped {alpha}-Cr{sub 2}O{sub 3} crystal. Structural, electronic and magnetic properties due to the singular impurity incorporation have been investigated and discussed in detail. Atomic shifts as well as computed Bader charges on atoms imply the importance of ionic nature in the atomic interactions in chromium oxide. The study improves our knowledge on how the crystalline lattice reacts on the presence of a Ca dopant. According to our research it is found that Ca impurity incorporation produces some local changes upon the electronic band structure of the material without occurrence of local states within the band-gap. It is found that Ca incorporation produces change in magnetic behaviour of the crystal: it becomes ferromagnetic.

  14. Mild cognitive deficits in patients with primary adrenal insufficiency.

    Science.gov (United States)

    Tiemensma, Jitske; Andela, Cornelie D; Biermasz, Nienke R; Romijn, Johannes A; Pereira, Alberto M

    2016-01-01

    The brain is a major target organ for cortisol considering its high density of glucocorticoid receptors. Several states of hypothalamus-pituitary-adrenal dysregulation point towards impairments in cognitive functioning. However, there is a very limited body of research on the effects of hypocortisolism on cognitive functioning. To evaluate cognitive functioning in patients with hypocortisolism (i.e., primary adrenal insufficiency (PAI)) and to examine the possible effect of postponing early-morning hydrocortisone intake on cognitive functioning. Thirty-one patients with PAI on regular morning hydrocortisone intake and 31 healthy matched controls underwent nine neuropsychological tests, evaluating memory and executive functioning. In addition, the effect of normal timing and postponement of morning hydrocortisone intake on neuropsychological tests were assessed in an additional 29 patients with PAI. Compared to controls, patients with PAI performed worse on auditory and visual memory tasks (all P ≤ 0.024) and executive functioning tasks (all P ≤ 0.012). In contrast, patients performed better on a concentration and an attention task (both Paffect the outcomes of neuropsychological tests. Patients on long-term hydrocortisone replacement for PAI show mild cognitive deficits compared to controls. There was no effect of postponement of regular hydrocortisone intake on cognition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  16. Sleep Restores Daytime Deficits in Procedural Memory in Children with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Prehn-Kristensen, Alexander; Molzow, Ina; Munz, Manuel; Wilhelm, Ines; Muller, Kathrin; Freytag, Damaris; Wiesner, Christian D.; Baving, Lioba

    2011-01-01

    Sleep supports the consolidation of declarative and procedural memory. While prefrontal cortex (PFC) activity supports the consolidation of declarative memory during sleep, opposite effects of PFC activity are reported with respect to the consolidation of procedural memory during sleep. Patients with attention-deficit/hyperactivity disorder (ADHD)…

  17. A Cognitive Distortions and Deficits Model of Suicide Ideation

    Directory of Open Access Journals (Sweden)

    Laura L. Fazakas-DeHoog

    2017-05-01

    Full Text Available Although cognitive distortions and deficits are known risk factors for the development and escalation of suicide ideation and behaviour, no empirical work has examined how these variables interact to predict suicide ideation. The current study proposes an integrative model of cognitive distortions (hopelessness and negative evaluations of self and future and deficits (problem solving deficits, problem solving avoidance, and cognitive rigidity. To test the integrity of this model, a sample of 397 undergraduate students completed measures of deficits, distortions, and current suicide ideation. A structural equation model demonstrated excellent fit, and findings indicated that only distortions have a direct effect on suicidal thinking, whereas cognitive deficits may exert their effects on suicide ideation via their reciprocal relation with distortions. Findings underscore the importance of both cognitive distortions and deficits for understanding suicidality, which may have implications for preventative efforts and treatment.

  18. Energy Deficit Required for Rapid Weight Loss in Elite Collegiate Wrestlers.

    Science.gov (United States)

    Kondo, Emi; Sagayama, Hiroyuki; Yamada, Yosuke; Shiose, Keisuke; Osawa, Takuya; Motonaga, Keiko; Ouchi, Shiori; Kamei, Akiko; Nakajima, Kohei; Higaki, Yasuki; Tanaka, Hiroaki; Takahashi, Hideyuki; Okamura, Koji

    2018-04-26

    To determine energy density for rapid weight loss (RWL) of weight-classified sports, eight male elite wrestlers were instructed to lose 6% of body mass (BM) within 53 h. Energy deficit during the RWL was calculated by subtracting total energy expenditure (TEE) determined using the doubly labeled water method (DLW) from energy intake (EI) assessed with diet records. It was also estimated from body composition change estimated with the four-component model (4C) and other conventional methods. BM decreased significantly by 4.7 ± 0.5 kg (6.4 ± 0.5%). Total body water loss was the major component of the BM loss (71.0 ± 7.6%). TEE was 9446 ± 1422 kcal, and EI was 2366 ± 1184 kcal during the RWL of 53-h; therefore, the energy deficit was 7080 ± 1525 kcal. Thus, energy density was 1507 ± 279 kcal/kg ∆BM during the RWL, comparable with values obtained using the 4C, three-component model, dual energy X-ray absorptiometry, and stable isotope dilution. Energy density for RWL of wrestlers is lower than that commonly used (7400 or 7700 kcal/kg ΔBM). Although RWL is not recommended, we propose that commonly practiced extreme energy restriction such as 7400 or 7700 kcal/kg ΔBM during RWL appears to be meaningless.

  19. Energy Deficit Required for Rapid Weight Loss in Elite Collegiate Wrestlers

    Directory of Open Access Journals (Sweden)

    Emi Kondo

    2018-04-01

    Full Text Available To determine energy density for rapid weight loss (RWL of weight-classified sports, eight male elite wrestlers were instructed to lose 6% of body mass (BM within 53 h. Energy deficit during the RWL was calculated by subtracting total energy expenditure (TEE determined using the doubly labeled water method (DLW from energy intake (EI assessed with diet records. It was also estimated from body composition change estimated with the four-component model (4C and other conventional methods. BM decreased significantly by 4.7 ± 0.5 kg (6.4 ± 0.5%. Total body water loss was the major component of the BM loss (71.0 ± 7.6%. TEE was 9446 ± 1422 kcal, and EI was 2366 ± 1184 kcal during the RWL of 53-h; therefore, the energy deficit was 7080 ± 1525 kcal. Thus, energy density was 1507 ± 279 kcal/kg ∆BM during the RWL, comparable with values obtained using the 4C, three-component model, dual energy X-ray absorptiometry, and stable isotope dilution. Energy density for RWL of wrestlers is lower than that commonly used (7400 or 7700 kcal/kg ΔBM. Although RWL is not recommended, we propose that commonly practiced extreme energy restriction such as 7400 or 7700 kcal/kg ΔBM during RWL appears to be meaningless.

  20. Edward C. Little Water Recycling Plant, El Segundo, CA: CA0063401

    Science.gov (United States)

    Joint EPA and Los Angeles Regional Water Quality Control Board NPDES Permit and Waiver from Secondary Treatment for the West Basin Municipal Water District Edward C. Little Water Recycling Plant, El Segundo, CA: CA0063401

  1. Central depression in nucleonic densities: Trend analysis in the nuclear density functional theory approach

    Science.gov (United States)

    Schuetrumpf, B.; Nazarewicz, W.; Reinhard, P.-G.

    2017-08-01

    Background: The central depression of nucleonic density, i.e., a reduction of density in the nuclear interior, has been attributed to many factors. For instance, bubble structures in superheavy nuclei are believed to be due to the electrostatic repulsion. In light nuclei, the mechanism behind the density reduction in the interior has been discussed in terms of shell effects associated with occupations of s orbits. Purpose: The main objective of this work is to reveal mechanisms behind the formation of central depression in nucleonic densities in light and heavy nuclei. To this end, we introduce several measures of the internal nucleonic density. Through the statistical analysis, we study the information content of these measures with respect to nuclear matter properties. Method: We apply nuclear density functional theory with Skyrme functionals. Using the statistical tools of linear least square regression, we inspect correlations between various measures of central depression and model parameters, including nuclear matter properties. We study bivariate correlations with selected quantities as well as multiple correlations with groups of parameters. Detailed correlation analysis is carried out for 34Si for which a bubble structure has been reported recently, 48Ca, and N =82 , 126, and 184 isotonic chains. Results: We show that the central depression in medium-mass nuclei is very sensitive to shell effects, whereas for superheavy systems it is firmly driven by the electrostatic repulsion. An appreciable semibubble structure in proton density is predicted for 294Og, which is currently the heaviest nucleus known experimentally. Conclusion: Our correlation analysis reveals that the central density indicators in nuclei below 208Pb carry little information on parameters of nuclear matter; they are predominantly driven by shell structure. On the other hand, in the superheavy nuclei there exists a clear relationship between the central nucleonic density and symmetry energy.

  2. Cognitive deficits in post-stroke aphasia

    Directory of Open Access Journals (Sweden)

    Milena V. Bonini

    2015-10-01

    Full Text Available The assessment of aphasics’ cognitive performance is challenging and such patients are generally excluded from studies that describe cognitive deficits after stroke. We evaluated aphasics’ performance in cognitive tasks compared to non-aphasic subjects. A sample of 47 patients (21 aphasics, 17 non-aphasics with left hemisphere lesions and 9 non-aphasics with right hemisphere lesions performed cognitive tasks (attention, verbal and visual memory, executive functions, visuospatial skills and praxis. Aphasic patients performed poorer than all non-aphasics in Digit Span (p < 0.001, Clock-Drawing Test (p = 0.006, Verbal memory (p = 0.002, Visual Memory (p < 0.01, Verbal Fluency (p < 0.001, and Gesture Praxis (p < 0.001. Aphasia severity correlated with performance in Trail Making test part B (p = 0.004, Digit Span forward (p < 0.001 and backwards (p = 0.011, and Gesture Praxis (p = 0.002. Aphasia is accompanied by deficits not always easy to be evaluated by cognitive tests due to speech production and motor impairments. Assessment of cognitive functions in aphasics might contribute to optimize therapeutic intervention.

  3. Dysrhythmia: a specific congenital rhythm perception deficit

    Directory of Open Access Journals (Sweden)

    Jacques eLaunay

    2014-02-01

    Full Text Available Why do some people have problems ‘feeling the beat’? Here we investigate participants with congenital impairments in musical rhythm perception and production. A web-based version of the Montreal Battery of Evaluation of Amusia (MBEA was used to screen for difficulties with rhythmic processing in a large sample and we identified three ‘dysrhythmic’ individuals who scored below cut-off for the rhythm subtest, but not the pitch-based subtests. Follow-up testing in the laboratory was conducted to characterize the nature of both rhythm perception and production deficits in these dysrhythmic individuals. We found that they differed from control participants when required to synchronize their tapping to an external stimulus with a metrical pulse, but not when required to tap spontaneously (with no external stimulus or to tap in time to an isochronous stimulus. Dysrhythmics exhibited a general tendency to tap at half the expected tempo when asked to synchronize to the beat of strongly metrical rhythms. These results suggest that the individuals studied here did not have motor production problems, but suffer from a selective rhythm perception deficit that influences the ability to entrain to metrical rhythms.

  4. Taxation, Fiscal Deficit and Inflation in Pakistan

    Directory of Open Access Journals (Sweden)

    Ghulam Rasool Madni

    2014-09-01

    Full Text Available Fiscal policy has more controversial debate regarding its effectiveness on different macroeconomic activities of an economy. Taxation and government expenditure are two main instruments of fiscal policy. This paper is aimed to analyze and update the effects of different instruments of fiscal policy on inflation in Pakistan economy. The data time span for this study is 1979-2013. The impact of fiscal policy on inflation is analyzed by utilizing the Bounds testing procedure and ARDL approach of co-integration which is a better estimation technique for small sample size. It is found that investment negatively and significantly affect the inflation rate. The outcomes of the study show that both types of taxes (direct and indirect are causing to increase the inflation level while fiscal deficit is also one of the reasons to increase the inflation in the country. The study proposed that government should decrease the level of expenditure to reduce the level of fiscal deficit and investment have to be promoted to decrease the inflation in the country. Furthermore, it is also suggested to decrease the level of taxation for controlling inflation.

  5. Stroke caused auditory attention deficits in children

    Directory of Open Access Journals (Sweden)

    Karla Maria Ibraim da Freiria Elias

    2013-01-01

    Full Text Available OBJECTIVE: To verify the auditory selective attention in children with stroke. METHODS: Dichotic tests of binaural separation (non-verbal and consonant-vowel and binaural integration - digits and Staggered Spondaic Words Test (SSW - were applied in 13 children (7 boys, from 7 to 16 years, with unilateral stroke confirmed by neurological examination and neuroimaging. RESULTS: The attention performance showed significant differences in comparison to the control group in both kinds of tests. In the non-verbal test, identifications the ear opposite the lesion in the free recall stage was diminished and, in the following stages, a difficulty in directing attention was detected. In the consonant- vowel test, a modification in perceptual asymmetry and difficulty in focusing in the attended stages was found. In the digits and SSW tests, ipsilateral, contralateral and bilateral deficits were detected, depending on the characteristics of the lesions and demand of the task. CONCLUSION: Stroke caused auditory attention deficits when dealing with simultaneous sources of auditory information.

  6. Electronic, Optical, and Lattice Dynamical Properties of Tetracalcium Trialuminate (Ca4Al6O13

    Directory of Open Access Journals (Sweden)

    Huayue Mei

    2018-03-01

    Full Text Available The electronic, optical, and lattice dynamical properties of tetracalcium trialuminate (Ca4Al6O13 with a special sodalite cage structure were calculated based on the density functional theory. Theoretical results show that Ca4Al6O13 is ductile and weakly anisotropic. The calculated Young’s modulus and Poisson ratio are 34.18 GPa and 0.32, respectively. Ca4Al6O13 is an indirect-gap semiconductor with a band gap of 5.41 eV. The top of the valence band derives from O 2p states, and the bottom of conduction band consists of Ca 3d states. Transitions from O 2p, 2s states to empty Ca 4s, 3d and Al 3s, 3p states constitute the major peaks of the imaginary part of the dielectric function. Ca4Al6O13 is a good UV absorber for photoelectric devices due to the high absorption coefficient and low reflectivity. The lattice vibration analysis reveals that O atoms contribute to the high-frequency portions of the phonon spectra, while Ca and Al atoms make important contributions to the middle- and low-frequency portions. At the center of the first Brillouin zone, lattice vibrations include the Raman active modes (E, A1, infrared active mode (T2, and silentmodes (T1, A2. Typical atomic displacement patterns were also investigated to understand the vibration modes more intuitively.

  7. Effects of Calcium Source on Biochemical Properties of Microbial CaCO3 Precipitation.

    Science.gov (United States)

    Xu, Jing; Du, Yali; Jiang, Zhengwu; She, Anming

    2015-01-01

    The biochemical properties of CaCO3 precipitation induced by Sporosarcina pasteurii, an ureolytic type microorganism, were investigated. Effects of calcium source on the precipitation process were examined, since calcium source plays a key role in microbiologically induced mineralization. Regardless of the calcium source type, three distinct stages in the precipitation process were identified by Ca(2+), NH4 (+), pH and cell density monitoring. Compared with stage 1 and 3, stage 2 was considered as the most critical part since biotic CaCO3 precipitation occurs during this stage. Kinetics studies showed that the microbial CaCO3 precipitation rate for calcium lactate was over twice of that for calcium nitrate, indicating that calcium lactate is more beneficial for the cell activity, which in turn determines urease production and CaCO3 precipitation. X-ray diffraction analysis confirmed the CaCO3 crystal as calcite, although scanning electron microscopy revealed a difference in crystal size and morphology if calcium source was different. The findings of this paper further suggest a promising application of microbiologically induced CaCO3 precipitation in remediation of surface and cracks of porous media, e.g., cement-based composites, particularly by using organic source of calcium lactate.

  8. Budget deficit, money growth and inflation: Empirical evidence from Vietnam

    OpenAIRE

    Khieu Van, Hoang

    2014-01-01

    This study empirically examines the nexus among budget deficit, money supply and inflation by using a monthly data set from January 1995 to December 2012 and a SVAR model with five endogenous variables, inflation, money growth, budget deficit growth, real GDP growth and interest rate. Since real GDP and budget deficit are unavailable on the monthly basis, we interpolate those series using Chow and Lin’s (1971) annualized approach from their annual series. Overall, we found that money growth h...

  9. Coupled Ca2+/H+ transport by cytoplasmic buffers regulates local Ca2+ and H+ ion signaling.

    Science.gov (United States)

    Swietach, Pawel; Youm, Jae-Boum; Saegusa, Noriko; Leem, Chae-Hun; Spitzer, Kenneth W; Vaughan-Jones, Richard D

    2013-05-28

    Ca(2+) signaling regulates cell function. This is subject to modulation by H(+) ions that are universal end-products of metabolism. Due to slow diffusion and common buffers, changes in cytoplasmic [Ca(2+)] ([Ca(2+)]i) or [H(+)] ([H(+)]i) can become compartmentalized, leading potentially to complex spatial Ca(2+)/H(+) coupling. This was studied by fluorescence imaging of cardiac myocytes. An increase in [H(+)]i, produced by superfusion of acetate (salt of membrane-permeant weak acid), evoked a [Ca(2+)]i rise, independent of sarcolemmal Ca(2+) influx or release from mitochondria, sarcoplasmic reticulum, or acidic stores. Photolytic H(+) uncaging from 2-nitrobenzaldehyde also raised [Ca(2+)]i, and the yield was reduced following inhibition of glycolysis or mitochondrial respiration. H(+) uncaging into buffer mixtures in vitro demonstrated that Ca(2+) unloading from proteins, histidyl dipeptides (HDPs; e.g., carnosine), and ATP can underlie the H(+)-evoked [Ca(2+)]i rise. Raising [H(+)]i tonically at one end of a myocyte evoked a local [Ca(2+)]i rise in the acidic microdomain, which did not dissipate. The result is consistent with uphill Ca(2+) transport into the acidic zone via Ca(2+)/H(+) exchange on diffusible HDPs and ATP molecules, energized by the [H(+)]i gradient. Ca(2+) recruitment to a localized acid microdomain was greatly reduced during intracellular Mg(2+) overload or by ATP depletion, maneuvers that reduce the Ca(2+)-carrying capacity of HDPs. Cytoplasmic HDPs and ATP underlie spatial Ca(2+)/H(+) coupling in the cardiac myocyte by providing ion exchange and transport on common buffer sites. Given the abundance of cellular HDPs and ATP, spatial Ca(2+)/H(+) coupling is likely to be of general importance in cell signaling.

  10. Cuento: Sangre de caña

    Directory of Open Access Journals (Sweden)

    Segundo Benjamín Corredor

    1967-09-01

    Full Text Available El viento se convertía en murmullo contra las hojas de los cañaverales y contra los techos semipelados del rancho. También menguaba el calor que maduraba los plantíos de caña y que hacía más efusiva la sangre de los moradores.

  11. Impact of seawater [Ca2+] on the calcification and calcite Mg / Ca of Amphistegina lessonii

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; Thoms, S.; Nehrke, G.; Reichart, G. J.; de Nooijer, L. J.; Bijma, J.

    2015-01-01

    Mg / Ca ratios in foraminiferal tests are routinely used as paleotemperature proxies, but on long timescales, they also hold the potential to reconstruct past seawater Mg / Ca. The impact of both temperature and seawater Mg / Ca on Mg incorporation in Foraminifera has been quantified by a number of

  12. The Twin Deficits Hypothesis: An Empirical Analysis for Tanzania

    Directory of Open Access Journals (Sweden)

    Manamba Epaphra

    2017-09-01

    Full Text Available This paper examines the relationship between current account and government budget deficits in Tanzania. The paper tests the validity of the twin deficits hypothesis, using annual time series data for the 1966-2015 period. The paper is thought to be significant because the concept of the twin deficit hypothesis is fraught with controversy. Some researches support the hypothesis that there is a positive relationship between current account deficits and fiscal deficits in the economy while others do not. In this paper, the empirical tests fail to reject the twin deficits hypothesis, indicating that rising budget deficits put more strain on the current account deficits in Tanzania. Specifically, the Vector Error Correction Model results support the conventional theory of a positive relationship between fiscal and external balances, with a relatively high speed of adjustment toward the equilibrium position. This evidence is consistent with a small open economy. To address the problem that may result from this kind of relationship, appropriate policy variables for reducing budget deficits such as reduction in non-development expenditure, enhancement of domestic revenue collection and actively fight corruption and tax evasion should be adopted. The government should also target export oriented firms and encourage an import substitution industry by creating favorable business environments.

  13. Musical, visual and cognitive deficits after middle cerebral artery infarction

    Directory of Open Access Journals (Sweden)

    Stephanie Rosemann

    2017-03-01

    Full Text Available The perception of music can be impaired after a stroke. This dysfunction is called amusia and amusia patients often also show deficits in visual abilities, language, memory, learning, and attention. The current study investigated whether deficits in music perception are selective for musical input or generalize to other perceptual abilities. Additionally, we tested the hypothesis that deficits in working memory or attention account for impairments in music perception. Twenty stroke patients with small infarctions in the supply area of the middle cerebral artery were investigated with tests for music and visual perception, categorization, neglect, working memory and attention. Two amusia patients with selective deficits in music perception and pronounced lesions were identified. Working memory and attention deficits were highly correlated across the patient group but no correlation with musical abilities was obtained. Lesion analysis revealed that lesions in small areas of the putamen and globus pallidus were connected to a rhythm perception deficit. We conclude that neither a general perceptual deficit nor a minor domain general deficit can account for impairments in the music perception task. But we find support for the modular organization of the music perception network with brain areas specialized for musical functions as musical deficits were not correlated to any other impairment.

  14. Musical, visual and cognitive deficits after middle cerebral artery infarction.

    Science.gov (United States)

    Rosemann, Stephanie; Brunner, Freimuth; Kastrup, Andreas; Fahle, Manfred

    2017-03-01

    The perception of music can be impaired after a stroke. This dysfunction is called amusia and amusia patients often also show deficits in visual abilities, language, memory, learning, and attention. The current study investigated whether deficits in music perception are selective for musical input or generalize to other perceptual abilities. Additionally, we tested the hypothesis that deficits in working memory or attention account for impairments in music perception. Twenty stroke patients with small infarctions in the supply area of the middle cerebral artery were investigated with tests for music and visual perception, categorization, neglect, working memory and attention. Two amusia patients with selective deficits in music perception and pronounced lesions were identified. Working memory and attention deficits were highly correlated across the patient group but no correlation with musical abilities was obtained. Lesion analysis revealed that lesions in small areas of the putamen and globus pallidus were connected to a rhythm perception deficit. We conclude that neither a general perceptual deficit nor a minor domain general deficit can account for impairments in the music perception task. But we find support for the modular organization of the music perception network with brain areas specialized for musical functions as musical deficits were not correlated to any other impairment.

  15. Ca-Dependent Folding of Human Calumenin

    Science.gov (United States)

    Mazzorana, Marco; Hussain, Rohanah; Sorensen, Thomas

    2016-01-01

    Human calumenin (hCALU) is a six EF-hand protein belonging to the CREC family. As other members of the family, it is localized in the secretory pathway and regulates the activity of SERCA2a and of the ryanodine receptor in the endoplasmic reticulum (ER). We have studied the effects of Ca2+ binding to the protein and found it to attain a more compact structure upon ion binding. Circular Dichroism (CD) measurements suggest a major rearrangement of the protein secondary structure, which reversibly switches from disordered at low Ca2+ concentrations to predominantly alpha-helical when Ca2+ is added. SAXS experiments confirm the transition from an unfolded to a compact structure, which matches the structural prediction of a trilobal fold. Overall our experiments suggest that calumenin is a Ca2+ sensor, which folds into a compact structure, capable of interacting with its molecular partners, when Ca2+ concentration within the ER reaches the millimolar range. PMID:26991433

  16. CaMKII in the Cardiovascular System: Sensing Redox States

    Science.gov (United States)

    Erickson, Jeffrey R.; He, B. Julie; Grumbach, Isabella M.; Anderson, Mark E

    2013-01-01

    The multifunctional Ca2+ and calmodulin-dependent protein kinase II (CaMKII) is now recognized to play a central role in pathological events in the cardiovascular system. CaMKII has diverse downstream targets that promote vascular disease, heart failure and arrhythmias, so improved understanding of CaMKII signaling has the potential to lead to new therapies for cardiovascular disease. CaMKII is a multimeric serine-threonine kinase that is initially activated by binding calcified calmodulin (Ca2+/CaM). Under conditions of sustained exposure to elevated Ca2+/CaM CaMKII transitions into a Ca2+/CaM-autonomous enzyme by two distinct but parallel processes. Autophosphorylation of threonine 287 in the CaMKII regulatory domain ‘traps’ CaMKII into an open configuration even after Ca2+/CaM unbinding. More recently, our group identified a pair of methionines (281/282) in the CaMKII regulatory domain that undergo a partially reversible oxidation which, like autophosphorylation, prevents CaMKII from inactivating after Ca2+/CaM unbinding. Here we review roles of CaMKII in cardiovascular disease with an eye to understanding how CaMKII may act as a transduction signal to connect pro-oxidant conditions into specific downstream pathological effects that are relevant to rare and common forms of cardiovascular disease. PMID:21742790

  17. Mobilization of Ca2+ by Cyclic ADP-Ribose from the Endoplasmic Reticulum of Cauliflower Florets1

    Science.gov (United States)

    Navazio, Lorella; Mariani, Paola; Sanders, Dale

    2001-01-01

    The NAD+ metabolite cADP-Rib (cADPR) elevates cytosolic free Ca2+ in plants and thereby plays a central role in signal transduction pathways evoked by the drought and stress hormone abscisic acid. cADPR is known to mobilize Ca2+ from the large vacuole of mature cells. To determine whether additional sites for cADPR-gated Ca2+ release reside in plant cells, microsomes from cauliflower (Brassica oleracea) inflorescences were subfractionated on sucrose density gradients, and the distribution of cADPR-elicited Ca2+ release was monitored. cADPR-gated Ca2+ release was detected in the heavy-density fractions associated with rough endoplasmic reticulum (ER). cADPR-dependent Ca2+ release co-migrated with two ER markers, calnexin and antimycin A-insensitive NADH-cytochrome c reductase activity. To investigate the possibility that contaminating plasma membrane in the ER-rich fractions was responsible for the observed release, plasma membrane vesicles were purified by aqueous two-phase partitioning, everted with Brij-58, and loaded with Ca2+: These vesicles failed to respond to cADPR. Ca2+ release evoked by cADPR at the ER was fully inhibited by ruthenium red and 8-NH2-cADPR, a specific antagonist of cADPR-gated Ca2+ release in animal cells. The presence of a Ca2+ release pathway activated by cADPR at higher plant ER reinforces the notion that, alongside the vacuole, the ER participates in Ca2+ signaling. PMID:11299392

  18. Disinhibition mediates a form of hippocampal long-term potentiation in area CA1.

    Directory of Open Access Journals (Sweden)

    Jake Ormond

    Full Text Available The hippocampus plays a central role in memory formation in the mammalian brain. Its ability to encode information is thought to depend on the plasticity of synaptic connections between neurons. In the pyramidal neurons constituting the primary hippocampal output to the cortex, located in area CA1, firing of presynaptic CA3 pyramidal neurons produces monosynaptic excitatory postsynaptic potentials (EPSPs followed rapidly by feedforward (disynaptic inhibitory postsynaptic potentials (IPSPs. Long-term potentiation (LTP of the monosynaptic glutamatergic inputs has become the leading model of synaptic plasticity, in part due to its dependence on NMDA receptors (NMDARs, required for spatial and temporal learning in intact animals. Using whole-cell recording in hippocampal slices from adult rats, we find that the efficacy of synaptic transmission from CA3 to CA1 can be enhanced without the induction of classic LTP at the glutamatergic inputs. Taking care not to directly stimulate inhibitory fibers, we show that the induction of GABAergic plasticity at feedforward inhibitory inputs results in the reduced shunting of excitatory currents, producing a long-term increase in the amplitude of Schaffer collateral-mediated postsynaptic potentials. Like classic LTP, disinhibition-mediated LTP requires NMDAR activation, suggesting a role in types of learning and memory attributed primarily to the former and raising the possibility of a previously unrecognized target for therapeutic intervention in disorders linked to memory deficits, as well as a potentially overlooked site of LTP expression in other areas of the brain.

  19. Effects of drought stress and different densities on oil yield and ...

    African Journals Online (AJOL)

    For evaluation of water deficit stress and planting density effects on the oil and biological yield attributes of sunflower, an experiment was conducted in a randomized complete block design (RCBD) based split plot factorial design in three replications in the research field of Baku State University, Baku, Azerbaijan, in 2009.

  20. Break-up of Ca-montmorillonite particles by Na-montmorillonite

    International Nuclear Information System (INIS)

    Hedstroem, Magnus; Birgersson, Martin

    2012-01-01

    -ionic clays are 490 and 120 NTU for Wy-Ca and Wy-Na respectively. The turbidity value for Ca-montmorillonite is actually preparation dependent. A mixed suspension of volume V with calcium fraction X Ca is obtained by mixing X Ca .V + (1-X Ca ).V. If the two types of clay were unaffected by the mixing then the expected turbidity of the mixed suspension would be a linear superposition, i.e., Turb(X Ca ) = X Ca . Turb(Ca)+(1-X Ca ).Turb(Na) as illustrated in the figure. However, the measured turbidities show large non-linearity and lie below the linear response. For X Ca ≤0.6 the turbidity is close to that of homo-ionic Wy-Na showing that the particle size (here referring to tactoid size) of Wy-Ca/Na does not differ significantly from homo-ionic Wy-Na. Evidently by just mixing Ca-montmorillonite with Na-montmorillonite the tactoids that are present in Wy-Ca break up. One could envisage that at high Ca fractions the mixing process could work in the opposite direction so the mixed montmorillonite would behave more like Wy-Ca. In that case the measured turbidity would lie above the linear superposition line. From Figure 1 we see instead that Turb(X Ca =0.9) lie close to the superposition line and Turb(X Ca =0.8) clearly falls below. Still the higher turbidity of the clay with X Ca =0.8 compared to homo-ionic Wy-Na indicates incomplete delamination or dispersion, which is also in accord with the observation of the 19 A diffraction peak also at low dry densities [4]. The mixing and break-up of Ca-montmorillonite by Na-montmorillonite is also demonstrated using centimetre-sized clay pieces of high density. These experiments show the qualitative difference between a homo-ionic Ca-montmorillonite and mixed Ca/Na-montmorillonite with X Ca <0.9. In homo-ionic Ca-montmorillonite the sol phase is virtually absent which is consistent with the fact that erosion of Ca-montmorillonite is never observed. (authors)

  1. CRISS power spectral density

    International Nuclear Information System (INIS)

    Vaeth, W.

    1979-04-01

    The correlation of signal components at different frequencies like higher harmonics cannot be detected by a normal power spectral density measurement, since this technique correlates only components at the same frequency. This paper describes a special method for measuring the correlation of two signal components at different frequencies: the CRISS power spectral density. From this new function in frequency analysis, the correlation of two components can be determined quantitatively either they stem from one signal or from two diverse signals. The principle of the method, suitable for the higher harmonics of a signal as well as for any other frequency combinations is shown for the digital frequency analysis technique. Two examples of CRISS power spectral densities demonstrates the operation of the new method. (orig.) [de

  2. Concentrations of Ca and Mg in early stages of sapwood decay in red spruce, eastern hemlock, red maple, and paper birch

    Science.gov (United States)

    Kevin T. Smith; Walter C. Shortle; Jody Jellison; Jon Connolly; Jonathan Schilling

    2007-01-01

    The decay of coarse woody debris is a key component in the formation of forest soil and in the biogeochemical cycles of Ca and Mg. We tracked changes in density and concentration of Ca and Mg in sapwood of red maple (Acer rubrum L.), red spruce (Picea rubens Sarg.), paper birch (Betula papyrifera Marsh.), and...

  3. High density dispersion fuel

    International Nuclear Information System (INIS)

    Hofman, G.L.

    1996-01-01

    A fuel development campaign that results in an aluminum plate-type fuel of unlimited LEU burnup capability with an uranium loading of 9 grams per cm 3 of meat should be considered an unqualified success. The current worldwide approved and accepted highest loading is 4.8 g cm -3 with U 3 Si 2 as fuel. High-density uranium compounds offer no real density advantage over U 3 Si 2 and have less desirable fabrication and performance characteristics as well. Of the higher-density compounds, U 3 Si has approximately a 30% higher uranium density but the density of the U 6 X compounds would yield the factor 1.5 needed to achieve 9 g cm -3 uranium loading. Unfortunately, irradiation tests proved these peritectic compounds have poor swelling behavior. It is for this reason that the authors are turning to uranium alloys. The reason pure uranium was not seriously considered as a dispersion fuel is mainly due to its high rate of growth and swelling at low temperatures. This problem was solved at least for relatively low burnup application in non-dispersion fuel elements with small additions of Si, Fe, and Al. This so called adjusted uranium has nearly the same density as pure α-uranium and it seems prudent to reconsider this alloy as a dispersant. Further modifications of uranium metal to achieve higher burnup swelling stability involve stabilization of the cubic γ phase at low temperatures where normally α phase exists. Several low neutron capture cross section elements such as Zr, Nb, Ti and Mo accomplish this in various degrees. The challenge is to produce a suitable form of fuel powder and develop a plate fabrication procedure, as well as obtain high burnup capability through irradiation testing

  4. Gap and density theorems

    CERN Document Server

    Levinson, N

    1940-01-01

    A typical gap theorem of the type discussed in the book deals with a set of exponential functions { \\{e^{{{i\\lambda}_n} x}\\} } on an interval of the real line and explores the conditions under which this set generates the entire L_2 space on this interval. A typical gap theorem deals with functions f on the real line such that many Fourier coefficients of f vanish. The main goal of this book is to investigate relations between density and gap theorems and to study various cases where these theorems hold. The author also shows that density- and gap-type theorems are related to various propertie

  5. Nuclear level density

    International Nuclear Information System (INIS)

    Cardoso Junior, J.L.

    1982-10-01

    Experimental data show that the number of nuclear states increases rapidly with increasing excitation energy. The properties of highly excited nuclei are important for many nuclear reactions, mainly those that go via processes of the compound nucleus type. In this case, it is sufficient to know the statistical properties of the nuclear levels. First of them is the function of nuclear levels density. Several theoretical models which describe the level density are presented. The statistical mechanics and a quantum mechanics formalisms as well as semi-empirical results are analysed and discussed. (Author) [pt

  6. Polarizable Density Embedding

    DEFF Research Database (Denmark)

    Olsen, Jógvan Magnus Haugaard; Steinmann, Casper; Ruud, Kenneth

    2015-01-01

    We present a new QM/QM/MM-based model for calculating molecular properties and excited states of solute-solvent systems. We denote this new approach the polarizable density embedding (PDE) model and it represents an extension of our previously developed polarizable embedding (PE) strategy. The PDE...... model is a focused computational approach in which a core region of the system studied is represented by a quantum-chemical method, whereas the environment is divided into two other regions: an inner and an outer region. Molecules belonging to the inner region are described by their exact densities...

  7. Holographic magnetisation density waves

    Energy Technology Data Exchange (ETDEWEB)

    Donos, Aristomenis [Centre for Particle Theory and Department of Mathematical Sciences, Durham University,Stockton Road, Durham, DH1 3LE (United Kingdom); Pantelidou, Christiana [Departament de Fisica Quantica i Astrofisica & Institut de Ciencies del Cosmos (ICC),Universitat de Barcelona,Marti i Franques 1, 08028 Barcelona (Spain)

    2016-10-10

    We numerically construct asymptotically AdS black brane solutions of D=4 Einstein theory coupled to a scalar and two U(1) gauge fields. The solutions are holographically dual to d=3 CFTs in a constant external magnetic field along one of the U(1)’s. Below a critical temperature the system’s magnetisation density becomes inhomogeneous, leading to spontaneous formation of current density waves. We find that the transition can be of second order and that the solutions which minimise the free energy locally in the parameter space of solutions have averaged stressed tensor of a perfect fluid.

  8. A Nanoindentation Study of the Plastic Deformation and Fracture Mechanisms in Single-Crystalline CaFe2As2

    Science.gov (United States)

    Frawley, Keara G.; Bakst, Ian; Sypek, John T.; Vijayan, Sriram; Weinberger, Christopher R.; Canfield, Paul C.; Aindow, Mark; Lee, Seok-Woo

    2018-04-01

    The plastic deformation and fracture mechanisms in single-crystalline CaFe2As2 has been studied using nanoindentation and density functional theory simulations. CaFe2As2 single crystals were grown in a Sn-flux, resulting in homogeneous and nearly defect-free crystals. Nanoindentation along the [001] direction produces strain bursts, radial cracking, and lateral cracking. Ideal cleavage simulations along the [001] and [100] directions using density functional theory calculations revealed that cleavage along the [001] direction requires a much lower stress than cleavage along the [100] direction. This strong anisotropy of cleavage strength implies that CaFe2As2 has an atomic-scale layered structure, which typically exhibits lateral cracking during nanoindentation. This special layered structure results from weak atomic bonding between the (001) Ca and Fe2As2 layers.

  9. Attention-deficit/hyperactivity disorder during adulthood.

    Science.gov (United States)

    Magnin, E; Maurs, C

    Attention-Deficit/Hyperactivity Disorder (ADHD), although considered a childhood-onset neurodevelopmental condition, is nevertheless a frequent and disabling condition in adults. A proportion of such patients are not diagnosed during childhood or adolescence, as diagnosis of the syndrome is rather complex, especially when other psychiatric, neurological or other neurodevelopmental conditions are also associated, yet comorbidities and consequences of ADHD are frequently observed in adults and older populations. As ADHD patients present to memory clinics with attentional and executive disorders, neuropsychological examinations of undiagnosed ADHD patients may reveal atypical cognitive profiles that can complicate the usual diagnostic procedure and increase the risk of delayed diagnosis or misdiagnosis. Thus, explorations of cognitive and/or behavioral disorders in adult populations should systematically screen for this neurodevelopmental condition. Accurate diagnosis could lead to non-pharmaceutical and/or pharmaceutical treatments to improve symptoms and quality of life for adult ADHD patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  10. The roles of endogenous CaMKII inhibitors in learning and memory.

    Directory of Open Access Journals (Sweden)

    Fabio Antonio Borges Vigil

    2014-03-01

    Full Text Available Calcium/ Calmodulin-dependent kinase 2 (CaMK2 is a serine/threonine kinase with a wide range of substrates. In the dendrites this kinase is the major post-synaptic density protein. A number of studies have established that CaMK2 is a fundamentally important for various learning and memory processes. Given this importance the activity of CaMK2 must be tightly regulated. Recently two endogenous inhibitor proteins of CaMK2, CaMK2N1 and CaMK2N2, have been identified. During contextual fear memory formation CaMK2N1 and CaMK2N2 increase in brain regions that are related to the task. However, the functions of CaMK2Ns are still unknown. Our aim was to study the physiological roles of these inhibitors in memory and learning process. For that purpose we used adeno-associated virus vector to either knockdown or overexpress one of the inhibitors. Animals were trained in contextual fear conditioning and their memory of the context was tested in two different time points. Treatment knocking down one of the inhibitors had no effect on memory formation but it inhibits memory maintenance. Overexpression of the other inhibitor prior to training blocked memory formation. On the other hand, overexpression of the same inhibitor after training had no effect on learning or memory of the task. We are currently studying the molecular effects of both treatments. We expect to be able to present data obtain with these experiments at the DENDRITES 2014.

  11. Juvenile Hippocampal CA2 Region Expresses Aggrecan

    Directory of Open Access Journals (Sweden)

    Asako Noguchi

    2017-05-01

    Full Text Available Perineuronal nets (PNNs are distributed primarily around inhibitory interneurons in the hippocampus, such as parvalbumin-positive interneurons. PNNs are also present around excitatory neurons in some brain regions and prevent plasticity in these neurons. A recent study demonstrated that PNNs also exist around mouse hippocampal pyramidal cells, which are the principle type of excitatory neurons, in the CA2 subregion and modulate the excitability and plasticity of these neurons. However, the development of PNNs in the CA2 region during postnatal maturation was not fully investigated. This study found that a main component of PNNs, aggrecan, existed in the pyramidal cell layer of the putative CA2 subarea prior to the appearance of the CA2 region, which was defined by the CA2 marker protein regulator of G protein signaling 14 (RGS14. We also found that aggrecan immunoreactivity was more evident in the anterior sections of the CA2 area than the posterior sections, which suggests that the function of CA2 PNNs varies along the anterior-posterior axis.

  12. Maternal dietary loads of alpha-tocopherol increase synapse density and glial synaptic coverage in the hippocampus of adult offspring

    Directory of Open Access Journals (Sweden)

    S. Salucci

    2014-05-01

    Full Text Available An increased intake of the antioxidant α-Tocopherol (vitamin E is recommended in complicated pregnancies, to prevent free radical damage to mother and fetus. However, the anti-PKC and antimitotic activity of α-Tocopherol raises concerns about its potential effects on brain development. Recently, we found that maternal dietary loads of α-Tocopherol through pregnancy and lactation cause developmental deficit in hippocampal synaptic plasticity in rat offspring. The defect persisted into adulthood, with behavioral alterations in hippocampus-dependent learning. Here, using the same rat model of maternal supplementation, ultrastructural morphometric studies were carried out to provide mechanistic interpretation to such a functional impairment in adult offspring by the occurrence of long-term changes in density and morphological features of hippocampal synapses. Higher density of axo-spinous synapses was found in CA1 stratum radiatum of α-Tocopherol-exposed rats compared to controls, pointing to a reduced synapse pruning. No morphometric changes were found in synaptic ultrastructural features, i.e., perimeter of axon terminals, length of synaptic specializations, extension of bouton-spine contact. Glia-synapse anatomical relationship was also affected. Heavier astrocytic coverage of synapses was observed in Tocopherol-treated offspring, notably surrounding axon terminals; moreover, the percentage of synapses contacted by astrocytic endfeet at bouton-spine interface (tripartite synapses was increased. These findings indicate that gestational and neonatal exposure to supranutritional tocopherol intake can result in anatomical changes of offspring hippocampus that last through adulthood. These include a surplus of axo-spinous synapses and an aberrant glia-synapse relationship, which may represent the morphological signature of previously described alterations in synaptic plasticity and hippocampus-dependent learning.

  13. PGC-1α accelerates cytosolic Ca2+ clearance without disturbing Ca2+ homeostasis in cardiac myocytes

    International Nuclear Information System (INIS)

    Chen, Min; Wang, Yanru; Qu, Aijuan

    2010-01-01

    Energy metabolism and Ca 2+ handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1α in cardiac Ca 2+ signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1α via adenoviral transduction. Our data shows that overexpressing PGC-1α improved myocyte contractility without increasing the amplitude of Ca 2+ transients, suggesting that myofilament sensitivity to Ca 2+ increased. Interestingly, the decay kinetics of global Ca 2+ transients and Ca 2+ waves accelerated in PGC-1α-expressing cells, but the decay rate of caffeine-elicited Ca 2+ transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca 2+ -ATPase (SERCA2a), but not Na + /Ca 2+ exchange (NCX) contribute to PGC-1α-induced cytosolic Ca 2+ clearance. Furthermore, PGC-1α induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1α did not disturb cardiac Ca 2+ homeostasis, because SR Ca 2+ load and the propensity for Ca 2+ waves remained unchanged. These data suggest that PGC-1α can ameliorate cardiac Ca 2+ cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1α-calcium handing pathway sheds new light on the role of PGC-1α in the therapy of cardiac diseases.

  14. Structural, dynamical & electronic properties of CaCuO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, B.K.; Agrawal, S. [Allahabad Univ. (India)

    1994-12-31

    The scalar relativistic version of an accurate first principles full potential self- consistent linearized muffin tin orbital (LMTO) method has been employed for describing the physical properties of the parent system of the high-Tc oxide superconductors, i.e., CaCuO2. The presently employed modified version of the LMTO method is quite fast and goes beyond the usual LMTO-ASA method in the sense that it permits a completely general shape of the potential and the charge density. Also, in contrast to LMTO-ASA, the present method is also capable of treating distorted lattice structures accurately. The calculated values of the lattice parameters of pure CaCuO2 lie within 3% of the experimentally measured values for the Sr-doped system Ca(.86)Sr(.14)CuO(2). The computed electronic structures and the density of states is quite similar to those of the other oxide superconductors, except of their three- dimensional character because of the presence of strong coupling between the closely spaced CuO2 layers. The van Hove singularity peak appears slightly below the Fermi level and a small concentration of oxygenation /or/ substitutional doping may pin it as the Fermi level. The calculated frequencies for some symmetric frozen phonons for undoped CaCuO2 are quite near to the measured data for the Sr-doped CaCuO2.

  15. Pyramidal neurons in the septal and temporal CA1 field of the human and hedgehog tenrec hippocampus.

    Science.gov (United States)

    Liagkouras, Ioannis; Michaloudi, Helen; Batzios, Christos; Psaroulis, Dimitrios; Georgiadis, Marios; Künzle, Heinz; Papadopoulos, Georgios C

    2008-07-07

    The present study examines comparatively the cellular density of disector-counted/Nissl-stained CA1 pyramidal neurons and the morphometric characteristics (dendritic number/length, spine number/density and Sholl-counted dendritic branch points/20 microm) of the basal and apical dendritic systems of Golgi-impregnated CA1 neurons, in the septal and temporal hippocampus of the human and hedgehog tenrec brain. The obtained results indicate that in both hippocampal parts the cellular density of the CA1 pyramidal neurons is lower in human than in tenrec. However, while the human pyramidal cell density is higher in the septal hippocampal part than in the temporal one, in the tenrec the density of these cells is higher in the temporal part. The dendritic tree of the CA1 pyramidal cells, more developed in the septal than in temporal hippocampus in both species studied, is in general more complex in the human hippocampus. The basal and the apical dendritic systems exhibit species related morphometric differences, while dendrites of different orders exhibit differences in their number and length, and in their spine density. Finally, in both species, as well as hippocampal parts and dendritic systems, changes of dendritic morphometric features along ascending dendritic orders fluctuate in a similar way, as do the number of dendritic branch points in relation to the distance from the neuron soma.

  16. Brain-specific Crmp2 deletion leads to neuronal development deficits and behavioural impairments in mice.

    Science.gov (United States)

    Zhang, Hongsheng; Kang, Eunchai; Wang, Yaqing; Yang, Chaojuan; Yu, Hui; Wang, Qin; Chen, Zheyu; Zhang, Chen; Christian, Kimberly M; Song, Hongjun; Ming, Guo-Li; Xu, Zhiheng

    2016-06-01

    Several genome- and proteome-wide studies have associated transcription and translation changes of CRMP2 (collapsing response mediator protein 2) with psychiatric disorders, yet little is known about its function in the developing or adult mammalian brain in vivo. Here we show that brain-specific Crmp2 knockout (cKO) mice display molecular, cellular, structural and behavioural deficits, many of which are reminiscent of neural features and symptoms associated with schizophrenia. cKO mice exhibit enlarged ventricles and impaired social behaviour, locomotor activity, and learning and memory. Loss of Crmp2 in the hippocampus leads to reduced long-term potentiation, abnormal NMDA receptor composition, aberrant dendrite development and defective synapse formation in CA1 neurons. Furthermore, knockdown of crmp2 specifically in newborn neurons results in stage-dependent defects in their development during adult hippocampal neurogenesis. Our findings reveal a critical role for CRMP2 in neuronal plasticity, neural function and behavioural modulation in mice.

  17. Vitamin D deficiency: infertility and neurodevelopmental diseases (attention deficit hyperactivity disorder, autism, and schizophrenia).

    Science.gov (United States)

    Berridge, Michael J

    2018-02-01

    The process of development depends on a number of signaling systems that regulates the progressive sequence of developmental events. Infertility and neurodevelopmental diseases, such as attention deficit hyperactivity disorder, autism spectrum disorders, and schizophrenia, are caused by specific alterations in these signaling processes. Calcium signaling plays a prominent role throughout development beginning at fertilization and continuing through early development, implantation, and organ differentiation such as heart and brain development. Vitamin D plays a major role in regulating these signaling processes that control development. There is an increase in infertility and an onset of neurodevelopmental diseases when vitamin D is deficient. The way in which vitamin D deficiency acts to alter development is a major feature of this review. One of the primary functions of vitamin D is to maintain the phenotypic stability of both the Ca 2+ and redox signaling pathways that play such a key role throughout development.

  18. A Tryst With Density

    Indian Academy of Sciences (India)

    best known for developing the density functional theory (DFT). This is an extremely ... lem that has become famous in popular culture is that of the planet. Tatooine. Fans of ... the Schrödinger equation (or, if relativistic effects are important, the Dirac .... it supplies a moral justification for one's subsequent endeav- ours along ...

  19. Density in Liquids.

    Science.gov (United States)

    Nesin, Gert; Barrow, Lloyd H.

    1984-01-01

    Describes a fourth-grade unit on density which introduces a concept useful in the study of chemistry and procedures appropriate to the chemistry laboratory. The hands-on activities, which use simple equipment and household substances, are at the level of thinking Piaget describes as concrete operational. (BC)

  20. Destiny from density

    OpenAIRE

    Seewaldt, Victoria L.

    2012-01-01

    The identification of a signalling protein that regulates the accumulation of fat and connective tissue in breasts may help to explain why high mammographic density is linked to breast-cancer risk and may provide a marker for predicting this risk.

  1. Polarizable Density Embedding

    DEFF Research Database (Denmark)

    Reinholdt, Peter; Kongsted, Jacob; Olsen, Jógvan Magnus Haugaard

    2017-01-01

    We analyze the performance of the polarizable density embedding (PDE) model-a new multiscale computational approach designed for prediction and rationalization of general molecular properties of large and complex systems. We showcase how the PDE model very effectively handles the use of large...

  2. Encoding, Memory, and Transcoding Deficits in Childhood Apraxia of Speech

    Science.gov (United States)

    Shriberg, Lawrence D.; Lohmeier, Heather L.; Strand, Edythe A.; Jakielski, Kathy J.

    2012-01-01

    A central question in Childhood Apraxia of Speech (CAS) is whether the core phenotype is limited to transcoding (planning/programming) deficits or if speakers with CAS also have deficits in auditory-perceptual "encoding" (representational) and/or "memory" (storage and retrieval of representations) processes. We addressed this and other questions…

  3. The Deficit and the Federal Budget. 1983 National Issues Forum.

    Science.gov (United States)

    Melville, Keith, Ed.

    Although designed for participants in the National Issues Forum, this booklet, which describes the impact of the federal deficit and the federal budget process, is also useful for secondary school social studies. The six sections begin with an introduction describing why the deficit grows yearly and why it is difficult for Congress to stop its…

  4. Pragmatic Deficits and Social Impairment in Children with ADHD

    Science.gov (United States)

    Staikova, Ekaterina; Gomes, Hilary; Tartter, Vivien; McCabe, Allyssa; Halperin, Jeffrey M.

    2013-01-01

    Background: Impaired social functioning has been well documented in individuals with attention-deficit/hyperactivity disorder (ADHD). Existing treatments for ADHD are effective for managing core symptoms, but have limited effectiveness at improving social skills, suggesting that social deficits in ADHD may not be directly related to core symptoms…

  5. Attention Deficit/Hyperactivity Disorder (ADHD): The Basics

    Science.gov (United States)

    ... Signs Treating ADHD Reprints For More Information Share Attention-Deficit/Hyperactivity Disorder (ADHD): The Basics Download PDF Download ePub Order ... daily life, it could be a sign of attention-deficit/hyperactivity disorder (ADHD). ADHD is a disorder that makes it ...

  6. Are Auditory and Visual Processing Deficits Related to Developmental Dyslexia?

    Science.gov (United States)

    Georgiou, George K.; Papadopoulos, Timothy C.; Zarouna, Elena; Parrila, Rauno

    2012-01-01

    The purpose of this study was to examine if children with dyslexia learning to read a consistent orthography (Greek) experience auditory and visual processing deficits and if these deficits are associated with phonological awareness, rapid naming speed and orthographic processing. We administered measures of general cognitive ability, phonological…

  7. Depression in adolescence:testing a social skills deficit theory

    NARCIS (Netherlands)

    van Beek, Y.|info:eu-repo/dai/nl/107292300

    2017-01-01

    C145. DEPRESSION IN ADOLESCENCE:TESTING A SOCIAL SKILLS DEFICIT THEORYVan Beek, Y. Utrecht University, NetherlandsThe Social Skill Deficit Model for depression suggeststhat less optimal social skills lead to negativefeedback of others, which in turn results in negativeself-views and depression.

  8. Psychosocial and Adaptive Deficits Associated with Learning Disability Subtypes

    Science.gov (United States)

    Backenson, Erica M.; Holland, Sara C.; Kubas, Hanna A.; Fitzer, Kim R.; Wilcox, Gabrielle; Carmichael, Jessica A.; Fraccaro, Rebecca L.; Smith, Amanda D.; Macoun, Sarah J.; Harrison, Gina L.; Hale, James B.

    2015-01-01

    Children with specific learning disabilities (SLD) have deficits in the basic psychological processes that interfere with learning and academic achievement, and for some SLD subtypes, these deficits can also lead to emotional and/or behavior problems. This study examined psychosocial functioning in 123 students, aged 6 to 11, who underwent…

  9. Exploring the nature of facial affect processing deficits in schizophrenia

    NARCIS (Netherlands)

    Wout, Mascha van 't; Aleman, Andre; Kessels, Roy P. C.; Cahn, Wiepke; Haan, Edward H. F. de; Kahn, Rene S.

    2007-01-01

    Schizophrenia has been associated with deficits in facial affect processing, especially negative emotions. However, the exact nature of the deficit remains unclear. The aim of the present study was to investigate whether schizophrenia patients have problems in automatic allocation of attention as

  10. Exploring the nature of facial affect processing deficits in schizophrenia.

    NARCIS (Netherlands)

    Wout, M. van 't; Aleman, A.; Kessels, R.P.C.; Cahn, W.; Haan, E.H.F. de; Kahn, R.S.

    2007-01-01

    Schizophrenia has been associated with deficits in facial affect processing, especially negative emotions. However, the exact nature of the deficit remains unclear. The aim of the present study was to investigate whether schizophrenia patients have problems in automatic allocation of attention as

  11. Attention Deficit Hyperactivity Disorder and Executive Function Impairment: An Overview.

    OpenAIRE

    Carruthers, Lindsey.

    2016-01-01

    As with any cognitive ability, attention is vulnerable to dysfunction. The most common attentional problem is attention deficit hyperactivity disorder (ADHD). This brief overview will highlight the symptoms and deficits associated with ADHD, its prevalence in today’s society, the association between executive function impairment and ADHD using Barkley’s (1997) work, and the personal and societal effects of the disorder.

  12. Test Review: Barkley Deficits in Executive Functioning Scale (BDEFS)

    Science.gov (United States)

    Allee-Smith, Paula J.; Winters, Rebecca R.; Drake, Amanda; Joslin, Amanda K.

    2013-01-01

    The Barkley Deficits in Executive Functioning Scale (BDEFS), authored by Russell A. Barkley and published by Guilford in 2011, is an individually administered assessment tool that may be used to evaluate adults ages 18 to 81. The purpose of this measure is to screen those who may be experiencing executive functioning (EF) deficits in…

  13. Neuropsychological Treatment of Attention Deficit Disorder in Infancy

    Science.gov (United States)

    Solovieva, Yulia; Quintanar, Luis

    2017-01-01

    The syndrome of attention deficit disorder is one of the most frequent pictures of disabilities in pre-scholars. The present study analyses the results of fulfillment of tasks for mechanisms of control and spatial functions. 14 pre-scholars with attention deficit disorder took part in the study. The neuropsychological evaluation was applied before…

  14. Effect of progressive water deficit stress on proline accumulation and ...

    African Journals Online (AJOL)

    Water deficit stress is one of the important factors limiting chickpea production in arid and semi-arid regions of West Asia and North Africa. When water deficit stress is imposed, different molecular and biochemical responses take place. This study was carried out to investigate proline accumulation and protein profiles of ...

  15. Genetic variation of response to water deficit in parental genotypes ...

    African Journals Online (AJOL)

    dgomi

    In this study, we investigated morphological and photosynthetic responses to water deficit in parental genotypes of M. ... for adaptation to water deficit in legumes is a prerequisite for any research aiming to improve legume yields. ...... tolerant genotypes in rainfed lowland rice. Field Crop. Res. 99:48-58. Rouached A, Slama I, ...

  16. Evaluation of Serum CEA, CA19-9, CA72-4, CA125 and Ferritin as Diagnostic Markers and Factors of Clinical Parameters for Colorectal Cancer.

    Science.gov (United States)

    Gao, Yanfeng; Wang, Jinping; Zhou, Yue; Sheng, Sen; Qian, Steven Y; Huo, Xiongwei

    2018-02-09

    Blood-based protein biomarkers have recently shown as simpler diagnostic modalities for colorectal cancer, while their association with clinical pathological characteristics is largely unknown. In this study, we not only examined the sensitivity and reliability of single/multiple serum markers for diagnosis, but also assessed their connection with pathological parameters from a total of 279 colorectal cancer patients. Our study shown that glycoprotein carcinoembryonic antigen (CEA) owns the highest sensitivity among single marker in the order of CEA > cancer antigen 72-4 (CA72-4) > cancer antigen 19-9 9 (CA19-9) > ferritin > cancer antigen 125 (CA125), while the most sensitive combined-markers for two to five were: CEA + CA72-4; CEA + CA72-4 + CA125; CEA + CA19-9 + CA72-4 + CA125; and CEA + CA19-9 + CA72-4 + CA125 + ferritin, respectively. We also demonstrated that patients who had positive preoperative serum CEA, CA19-9, or CA72-4 were more likely with lymph node invasion, positive CA125 were prone to have vascular invasion, and positive CEA or CA125 were correlated with perineural invasion. In addition, positive CA19-9, CA72-4, or CA125 was associated with poorly differentiated tumor, while CEA, CA19-9, CA72-4, CA125 levels were positively correlated with pathological tumor-node-metastasis stages. We here conclude that combined serum markers can be used to not only diagnose colorectal cancer, but also appraise the tumor status for guiding treatment, evaluation of curative effect, and prognosis of patients.

  17. Two-body density matrix for closed s-d shell nuclei

    International Nuclear Information System (INIS)

    Dimitrova, S.S.; Kadrev, D.N.; Antonov, A.N.; Stoitsov, M.V.

    2000-01-01

    The two-body density matrix for 4 He, 16 O and 40 Ca within the Low-order approximation of the Jastrow correlation method is considered. Closed analytical expressions for the two-body density matrix, the center of mass and relative local densities and momentum distributions are presented. The effects of the short-range correlations on the two-body nuclear characteristics are investigated. (orig.)

  18. Heterozygote deficits in cyst plant-parasitic nematodes: possible causes and consequences.

    Science.gov (United States)

    Montarry, Josselin; Jan, Pierre-Loup; Gracianne, Cecile; Overall, Andrew D J; Bardou-Valette, Sylvie; Olivier, Eric; Fournet, Sylvain; Grenier, Eric; Petit, Eric J

    2015-04-01

    Deviations of genotypic frequencies from Hardy-Weinberg equilibrium (HWE) expectations could reveal important aspects of the biology of populations. Deviations from HWE due to heterozygote deficits have been recorded for three plant-parasitic nematode species. However, it has never been determined whether the observed deficits were due (i) to the presence of null alleles, (ii) to a high level of consanguinity and/or (iii) to a Wahlund effect. The aim of the present work was, while taking into the possible confounding effect of null alleles, to disentangle consanguinity and Wahlund effect in natural populations of those three economically important cyst nematodes using microsatellite markers: Globodera pallida, G. tabacum and Heterodera schachtii, pests of potato, tobacco and sugar beet, respectively. The results show a consistent pattern of heterozygote deficiency in the three nematode species sampled at the spatial scale of the host plant. We demonstrate that the prevalence of null alleles is weak and that heterozygote deficits do not have a single origin. Our results suggested that it is restricted dispersal that leads to heterozygote deficits through both consanguinity and substructure, which effects can be linked to soil movement, cyst density, and the number of generations per year. We discuss potential implications for the durability of plant resistances that are used to protect crops against parasites in which mating between relatives occur. While consanguineous mating leads to homozygosity at all loci, including loci governing avirulence/virulence, which favours the expression of virulence when recessive, the Wahlund effect is expected to have no particular effect on the adaptation of nematodes to resistances. © 2015 John Wiley & Sons Ltd.

  19. Low bone mineral density in ambulatory persons with cerebral palsy? A systematic review.

    Science.gov (United States)

    Mus-Peters, Cindy T R; Huisstede, Bionka M A; Noten, Suzie; Hitters, Minou W M G C; van der Slot, Wilma M A; van den Berg-Emons, Rita J G

    2018-05-22

    Non-ambulatory persons with cerebral palsy are prone to low bone mineral density. In ambulatory persons with cerebral palsy, bone mineral density deficits are expected to be small or absent, but a consensus conclusion is lacking. In this systematic review bone mineral density in ambulatory persons with cerebral palsy (Gross Motor Function Classification Scales I-III) was studied. Medline, Embase, and Web of Science were searched. According to international guidelines, low bone mineral density was defined as Z-score ≤ -2.0. In addition, we focused on Z-score ≤ -1.0 because this may indicate a tendency towards low bone mineral density. We included 16 studies, comprising 465 patients aged 1-65 years. Moderate and conflicting evidence for low bone mineral density (Z-score ≤ -2.0) was found for several body parts (total proximal femur, total body, distal femur, lumbar spine) in children with Gross Motor Function Classification Scales II and III. We found no evidence for low bone mineral density in children with Gross Motor Function Classification Scale I or adults, although there was a tendency towards low bone mineral density (Z-score ≤ -1.0) for several body parts. Although more high-quality research is needed, results indicate that deficits in bone mineral density are not restricted to non-ambulatory people with cerebral palsy. Implications for Rehabilitation Although more high-quality research is needed, including adults and fracture risk assessment, the current study indicates that deficits in bone mineral density are not restricted to non-ambulatory people with CP. Health care professionals should be aware that optimal nutrition, supplements on indication, and an active lifestyle, preferably with weight-bearing activities, are important in ambulatory people with CP, also from a bone quality point-of-view. If indicated, medication and fall prevention training should be prescribed.

  20. Sustainable Seas Student Intertidal Monitoring Project, Duxbury Reef, Bolinas, CA

    Science.gov (United States)

    Soave, K.; Dean, A.; Prescutti, K.; Ball, O.; Chang, E.; Darakananda, K.; Jessup, K.; Poutian, J.; Schwalbe, H.; Storm, E.

    2008-12-01

    The Sustainable Seas Student Monitoring Project at the Branson School in Ross, CA has monitored Duxbury Reef in Bolinas, CA since 1999, in cooperation with the Farallones Marine Sanctuary Association and the Gulf of Farallones National Marine Sanctuary. Goals of the project include: 1) To monitor the rocky intertidal habitat and develop a baseline database of invertebrates and algal density and abundance; 2) To contribute to the conservation of the rocky intertidal habitat through education of students and visitors about intertidal species and requirements for maintaining a healthy, diverse intertidal ecosystem; 3) To increase stewardship in the Gulf of the Farallones National Marine Sanctuary; and 4) To contribute abundance and population data on key algae and invertebrate species to the national database, LiMPETS (Long Term Monitoring Program and Experiential Training for Students). Student volunteers complete an intensive training course on the natural history of intertidal invertebrates and algae, identification of key species, rocky intertidal ecology, interpretation and monitoring techniques, and history of the sanctuary. Students identify and count key invertebrate and algae species along two permanent transects (A and B), and using randomly determined points within a permanent 100 m2 area, three times per year (fall, winter, and late spring). Using the data collected since 2004, we will analyze the population densities of aggregating anemones, Anthopleura elegantissima, for seasonal abundance variations as well as long-term population trends. We will also follow the seasonal and long-term population fluctuations of red algal turf, Endocladia muricata and Gelidium coulteri, and black turban snails, Tegula funebralis. Comparing populations of turf algae and the herbivorous black turban snails gathered before and after the November 7, 2007 San Francisco Bay oil spill shows very little impact on the Duxbury Reef intertidal inhabitants. Future analyses will

  1. Rescue of Learning and Memory Deficits in the Human Nonsyndromic Intellectual Disability Cereblon Knock-Out Mouse Model by Targeting the AMP-Activated Protein Kinase-mTORC1 Translational Pathway.

    Science.gov (United States)

    Bavley, Charlotte C; Rice, Richard C; Fischer, Delaney K; Fakira, Amanda K; Byrne, Maureen; Kosovsky, Maria; Rizzo, Bryant K; Del Prete, Dolores; Alaedini, Armin; Morón, Jose A; Higgins, Joseph J; D'Adamio, Luciano; Rajadhyaksha, Anjali M

    2018-03-14

    A homozygous nonsense mutation in the cereblon ( CRBN ) gene results in autosomal recessive, nonsyndromic intellectual disability that is devoid of other phenotypic features, suggesting a critical role of CRBN in mediating learning and memory. In this study, we demonstrate that adult male Crbn knock-out ( Crbn KO ) mice exhibit deficits in hippocampal-dependent learning and memory tasks that are recapitulated by focal knock-out of Crbn in the adult dorsal hippocampus, with no changes in social or repetitive behavior. Cellular studies identify deficits in long-term potentiation at Schaffer collateral CA1 synapses. We further show that Crbn is robustly expressed in the mouse hippocampus and Crbn KO mice exhibit hyperphosphorylated levels of AMPKα (Thr172). Examination of processes downstream of AMP-activated protein kinase (AMPK) finds that Crbn KO mice have a selective impairment in mediators of the mTORC1 translation initiation pathway in parallel with lower protein levels of postsynaptic density glutamatergic proteins and higher levels of excitatory presynaptic markers in the hippocampus with no change in markers of the unfolded protein response or autophagy pathways. Acute pharmacological inhibition of AMPK activity in adult Crbn KO mice rescues learning and memory deficits and normalizes hippocampal mTORC1 activity and postsynaptic glutamatergic proteins without altering excitatory presynaptic markers. Thus, this study identifies that loss of Crbn results in learning, memory, and synaptic defects as a consequence of exaggerated AMPK activity, inhibition of mTORC1 signaling, and decreased glutamatergic synaptic proteins. Thus, Crbn KO mice serve as an ideal model of intellectual disability to further explore molecular mechanisms of learning and memory. SIGNIFICANCE STATEMENT Intellectual disability (ID) is one of the most common neurodevelopmental disorders. The cereblon ( CRBN ) gene has been linked to autosomal recessive, nonsyndromic ID, characterized by an

  2. ANALYSIS OF BUDGET DEFICIT AND ITS PROBLEMS IN LITHUANIA

    Directory of Open Access Journals (Sweden)

    F. Jaseviciene

    2015-10-01

    Full Text Available Budget deficit is one of the most important parts of macroeconomics. Since 1990, the government of the Lithuanian Republic has been faced with problems in balancing the budget deficit; most of the years, the country’s budget was deficit with the lack of incoming money flow. The budget deficit value in Lithuania has been a significant theme since 2004, when Lithuania became part of the European Union, and one of the liabilities was to insure the litas replacement with euro currency and the budget deficit was one of the Maastricht’s criteria. Also it is very important to maintain effective management of public finances. The government is responsible for managing the country’s budget in respect to various economical parameters, for example, GDP, inflation rate, unemployment rate, etc., in order to plan income level and distribute it to the relevant economic areas. Also, the budget deficit’s problems are revealed in this article.

  3. Attention-deficit hyperactivity disorder (ADHD) and tuberous sclerosis complex.

    Science.gov (United States)

    D'Agati, Elisa; Moavero, Romina; Cerminara, Caterina; Curatolo, Paolo

    2009-10-01

    The neurobiological basis of attention-deficit hyperactivity disorder (ADHD) in tuberous sclerosis complex is still largely unknown. Cortical tubers may disrupt several brain networks that control different types of attention. Frontal lobe dysfunction due to seizures or epileptiform electroencephalographic discharges may perturb the development of brain systems that underpin attentional and hyperactive functions during a critical early stage of brain maturation. Comorbidity of attention-deficit hyperactivity disorder (ADHD) with mental retardation and autism spectrum disorders is frequent in children with tuberous sclerosis. Attention-deficit hyperactivity disorder (ADHD) may also reflect a direct effect of the abnormal genetic program. Treatment of children with tuberous sclerosis complex with combined symptoms of attention-deficit hyperactivity disorder (ADHD) and epilepsy may represent a challenge for clinicians, because antiepileptic therapy and drugs used to treat attention-deficit hyperactivity disorder (ADHD) may aggravate the clinical picture of each other.

  4. Enriched environment ameliorates depression-induced cognitive deficits and restores abnormal hippocampal synaptic plasticity.

    Science.gov (United States)

    Mahati, K; Bhagya, V; Christofer, T; Sneha, A; Shankaranarayana Rao, B S

    2016-10-01

    Severe depression compromises structural and functional integrity of the brain and results in impaired learning and memory, maladaptive synaptic plasticity as well as degenerative changes in the hippocampus and amygdala. The precise mechanisms underlying cognitive dysfunctions in depression remain largely unknown. On the other hand, enriched environment (EE) offers beneficial effects on cognitive functions, synaptic plasticity in the hippocampus. However, the effect of EE on endogenous depression associated cognitive dysfunction has not been explored. Accordingly, we have attempted to address this issue by investigating behavioural, structural and synaptic plasticity mechanisms in an animal model of endogenous depression after exposure to enriched environment. Our results demonstrate that depression is associated with impaired spatial learning and enhanced anxiety-like behaviour which is correlated with hypotrophy of the dentate gyrus and amygdalar hypertrophy. We also observed a gross reduction in the hippocampal long-term potentiation (LTP). We report a complete behavioural recovery with reduced indices of anhedonia and behavioural despair, reduced anxiety-like behaviour and improved spatial learning along with a complete restoration of dentate gyrus and amygdalar volumes in depressive rats subjected to EE. Enrichment also facilitated CA3-Schaffer collateral LTP. Our study convincingly proves that depression-induces learning deficits and impairs hippocampal synaptic plasticity. It also highlights the role of environmental stimuli in restoring depression-induced cognitive deficits which might prove vital in outlining more effective strategies to treat major depressive disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Possible Mechanisms Involved in Attenuation of Lipopolysaccharide-Induced Memory Deficits by Methyl Jasmonate in Mice.

    Science.gov (United States)

    Eduviere, Anthony Taghogho; Umukoro, Solomon; Adeoluwa, Olusegun A; Omogbiya, Itivere Adrian; Aluko, Oritoke Modupe

    2016-12-01

    This present study was carried out to investigate the likely mechanisms by which methyl jasmonate (MJ), 'an agent widely used in aromatherapy for neurological disorders, attenuates lipopolysaccharide (LPS)-induced memory deficits in mice. Mice were given intraperitoneal administration of LPS (250 µg/kg) alone or in combination with MJ (10-40 mg/kg), donepezil, DP (1 mg/kg), or vehicle for 7 successive days. Thereafter, memory was assessed using object recognition test (ORT). Acetylcholinesterase and myeloperoxidase activities were estimated in brain tissue homogenates. Brain levels of nitric oxide and markers of oxidative stress as well as histopathologic changes of the prefrontal cortex and cornu ammonis 1 (CA1) of the hippocampal region were also assessed. MJ (10-40 mg/kg) attenuated LPS-induced memory impairment in ORT. Moreover, the increased brain activities of acetylcholinesterase and myeloperoxidase enzymes were suppressed by MJ when compared with control (p memory deficits via mechanisms related to inhibition of acetylcholinesterase, myeloperoxidase, oxidative stress and neuronal degeneration.

  6. Regulated release of Ca2+ from respiring mitochondria by Ca2+/2H+ antiport.

    Science.gov (United States)

    Fiskum, G; Lehninger, A L

    1979-07-25

    Simultaneous measurements of oxygen consumption and transmembrane transport of Ca2+, H+, and phosphate show that the efflux of Ca2+ from respiring tightly coupled rat liver mitochondria takes place by an electroneutral Ca2+/2H+ antiport process that is ruthenium red-insensitive and that is regulated by the oxidation-reduction state of the mitochondrial pyridine nucleotides. When mitochondrial pyridine nucleotides are kept in a reduced steady state, the efflux of Ca2+ is inhibited; when they are in an oxidized state, Ca2+ efflux is activated. These processes were demonstrated by allowing phosphate-depleted mitochondria respiring on succinate in the presence of rotenone to take up Ca2+ from the medium. Upon subsequent addition of ruthenium red to block Ca2+ transport via the electrophoretic influx pathway, and acetoacetate, to bring mitochondrial pyridine nucleotides into the oxidized state, Ca2+ efflux and H+ influx ensued. The observed H+ influx/Ca2+ efflux ratio was close to the value 2.0 predicted for the operation of an electrically neutral Ca2+/2H+ antiport process.

  7. Reduced endogenous Ca2+ buffering speeds active zone Ca2+ signaling.

    Science.gov (United States)

    Delvendahl, Igor; Jablonski, Lukasz; Baade, Carolin; Matveev, Victor; Neher, Erwin; Hallermann, Stefan

    2015-06-09

    Fast synchronous neurotransmitter release at the presynaptic active zone is triggered by local Ca(2+) signals, which are confined in their spatiotemporal extent by endogenous Ca(2+) buffers. However, it remains elusive how rapid and reliable Ca(2+) signaling can be sustained during repetitive release. Here, we established quantitative two-photon Ca(2+) imaging in cerebellar mossy fiber boutons, which fire at exceptionally high rates. We show that endogenous fixed buffers have a surprisingly low Ca(2+)-binding ratio (∼ 15) and low affinity, whereas mobile buffers have high affinity. Experimentally constrained modeling revealed that the low endogenous buffering promotes fast clearance of Ca(2+) from the active zone during repetitive firing. Measuring Ca(2+) signals at different distances from active zones with ultra-high-resolution confirmed our model predictions. Our results lead to the concept that reduced Ca(2+) buffering enables fast active zone Ca(2+) signaling, suggesting that the strength of endogenous Ca(2+) buffering limits the rate of synchronous synaptic transmission.

  8. Extremely Elevated CA 125 and CA 19-9 in Endometrioma; A Case Series

    Directory of Open Access Journals (Sweden)

    Vugar Bayramov

    2010-03-01

    Full Text Available Although endometriosis is a benign condition, increased levels of the tumor markers CA 125 and CA 19-9 may be seen. However, these tumor markers reach to very high levels, rarely. In this report, 4 patients between 20 and 43 year-old with extremely elevated CA 125, CA 19-9 and CA 15-3 levels are discussed. In endometriosis extremely increased tumor markers are determined in the case of ruptured endometrioma cyst. There are two mechanisms to clarify extremely elevated levels of CA 125 in endometriosis. First, the peritoneal irritation of CA 125 molecule after the rupture of endometioma cyst and CA 125 secretion from the periton. And the second is penetration of the CA 125 moecule easily to the circulation through the peritoneal endothelial surface after the cyst rupture. In conclusion, the diagnosis of ruptured endometrioma cyst should be kept in mind especially in young patients with extremely elevated serum CA 125 levels with regard to the history and ultrasonographical signs and invasive procedures should be avoided.

  9. Insight into the optoelectronic and thermoelectric properties of Ca-based Zintl phase CaCd2X2 (X = P, As) from first principles calculation

    Science.gov (United States)

    Belfarh, T.; Batouche, M.; Seddik, T.; Uğur, G.; Omran, S. Bin; Bouhemadou, A.; Sandeep; Wang, Xiaotian; Sun, Xiao-Wei; Khenata, R.

    2018-06-01

    We have studied the structural, optical, electronic and thermoelectric properties of the CaCd2X2 (X = P, As) compounds by using the full-potential augmented plane wave plus local orbitals method (FP-APW + lo). The exchange-correlation potential was treated using both the gradient generalized approximation (WC-GGA) and local density approximation (LDA). The estimated structural parameters, including the lattice parameters and internal coordinates agree well with the available experimental data. Our computed band structure shows that both studied compounds are semiconductors, with direct band gaps (Γ-Γ) of approximately 1.78 eV and 1.2 eV for CaCd2P2 and CaCd2As2, respectively, using GGA-TB-mBJ approach. The calculated optical spectra reveal a strong response of these materials in the energy range between the visible light and extreme UV regions, making them a good candidate for optoelectronic devices. Thermoelectric parameters, such as thermal conductivity, electrical conductivity, Seebeck coefficient, power factor and figure of merit were calculated. We note that both the CaCd2P2 and CaCd2As2 compounds show promising thermoelectric properties.

  10. Low-lying dipole response in the stable 40,48Ca nuclei within the second random-phase approximation

    International Nuclear Information System (INIS)

    Gambacurta, D.; Grasso, M.; Catara, F.

    2012-01-01

    The low-lying dipole strength distributions of 40 CaCa and 48 Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle −2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle −1 hole nature and its transition densities.

  11. Low-lying dipole response in the stable 40,48Ca nuclei within the second random-phase approximation

    Science.gov (United States)

    Gambacurta, D.; Grasso, M.; Catara, F.

    2012-10-01

    The low-lying dipole strength distributions of 40CaCa and 48Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle -2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle -1 hole nature and its transition densities.

  12. Vacancy induced metallicity at the CaHfO3/SrTiO3 interface

    KAUST Repository

    Nazir, Safdar; Pulikkotil, J. J.; Schwingenschlö gl, Udo; Singh, Nirpendra

    2011-01-01

    Density functional theory is used to study the electronic properties of the oxide heterointerfaceCaHfO3/SrTiO3. Structural relaxation is carried out with and without O vacancies. As compared to related interfaces, strongly reduced octahedral distortions are found. Stoichiometric interfaces between the wide band gap insulatorsCaHfO3 and SrTiO3 turn out to exhibit an insulating state. However, interface metallicity is introduced by O vacancies, in agreement with experiment. The reduced octahedral distortions and necessity of O deficiency indicate a less complicated mechanism for the creation of the interfacial electron gas.

  13. Vacancy induced metallicity at the CaHfO3/SrTiO3 interface

    KAUST Repository

    Nazir, Safdar

    2011-03-31

    Density functional theory is used to study the electronic properties of the oxide heterointerfaceCaHfO3/SrTiO3. Structural relaxation is carried out with and without O vacancies. As compared to related interfaces, strongly reduced octahedral distortions are found. Stoichiometric interfaces between the wide band gap insulatorsCaHfO3 and SrTiO3 turn out to exhibit an insulating state. However, interface metallicity is introduced by O vacancies, in agreement with experiment. The reduced octahedral distortions and necessity of O deficiency indicate a less complicated mechanism for the creation of the interfacial electron gas.

  14. EnviroAtlas - Fresno, CA - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Fresno, CA EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  15. Social skills deficits and their association with Internet addiction and activities in adolescents with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Chou, Wen-Jiun; Huang, Mei-Feng; Chang, Yu-Ping; Chen, Yu-Min; Hu, Huei-Fan; Yen, Cheng-Fang

    2017-03-01

    Background and aims The aims of this study were to examine the association between social skills deficits and Internet addiction and activities in adolescents with attention-deficit/hyperactivity disorder (ADHD) as well as the moderators for this association. Methods A total of 300 adolescents, aged between 11 and 18 years, who had been diagnosed with ADHD participated in this study. Their Internet addiction levels, social skills deficits, ADHD, parental characteristics, and comorbidities were assessed. The various Internet activities that the participants engaged in were also examined. Results The associations between social skills deficits and Internet addiction and activities and the moderators of these associations were examined using logistic regression analyses. Social skills deficits were significantly associated with an increased risk of Internet addiction after adjustment for the effects of other factors [odds ratio (OR) = 1.049, 95% confidence interval (CI) = 1.030-1.070]. Social skills deficits were also significantly associated with Internet gaming and watching movies. The maternal occupational socioeconomic levels of the participants moderated the association between social skills deficits and Internet addiction. Conclusions Social skills deficits should be considered targets in prevention and intervention programs for treating Internet addiction among adolescents with ADHD.

  16. Impact of Executive Function Deficits and Attention-Deficit/Hyperactivity Disorder (ADHD) on Academic Outcomes in Children

    Science.gov (United States)

    Biederman, Joseph; Monuteaux, Michael C.; Doyle, Alysa E.; Seidman, Larry J.; Wilens, Timothy E.; Ferrero, Frances; Morgan, Christie L.; Faraone, Stephen V.

    2004-01-01

    The association between executive function deficits (EFDs) and functional outcomes were examined among children and adolescents with attention-deficit/hyperactivity disorder (ADHD). Participants were children and adolescents with (n = 259) and without (n = 222) ADHD, as ascertained from pediatric and psychiatric clinics. The authors defined EFD as…

  17. XES studies of density of states of high temperature superconductors

    Science.gov (United States)

    Jasiolek, Gabriel

    1991-01-01

    X-ray emission spectroscopic studies concerning the superconducting crystals, thin films, and ceramics of the Y-Ba-Cu-O, Tm-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Bi-Pb-Sr-Ca-Cu-O, and Tl-Ba-Ca-Cu-O types are presented. The contributions of the 13d(9)L, 13d(10)L, 13d(10)LL, and 13d(10)L(2) configurations, where L denotes a ligand hole at the oxygen orbitals in the spectroscopic pattern of these superconductors are discussed. An attempt to connect the x-ray 'as registered' Cu L(alpha) emission spectra with the density of states close to the Fermi level, considering an influence of the CuL3 absorption edge, is presented. The corrected intensity distributions below the Fermi level are found to correspond to the theoretical density of states. Furthermore, an approach to the average valence of copper basing on the account of the self-absorption and fluorescence effects and on the configurations listed above is shown. The average valence of copper in the materials investigated is estimated to lie in the range of +2.10 to 2.32 when the formal trivalent copper is considered as that characterized by the 13d(9)L configuration. The density of states at the Fermi level was estimated to be 2.4 states/eV-cell for a Bi-Sr-Ca-Cu-O crystal and 3.6 states/eV-cell for a Tl-Ba-Ca-CU-O ceramic.

  18. Ischemic damage in hippocampal CA1 is dependent on glutamate release and intact innervation from CA3

    DEFF Research Database (Denmark)

    Benveniste, H; Jørgensen, M B; Sandberg, M

    1989-01-01

    The removal of glutamatergic afferents to CA1 by destruction of the CA3 region is known to protect CA1 pyramidal cells against 10 min of transient global ischemia. To investigate further the pathogenetic significance of glutamate, we measured the release of glutamate in intact and CA3-lesioned CA...

  19. YouthCaN 2001 / Sirje Janikson

    Index Scriptorium Estoniae

    Janikson, Sirje

    2001-01-01

    Aprillis 2001 toimus keskkonnateemaline õpilaskonverents YouthCaN 2001 Ameerika Loodusajaloo Muuseumis New Yorkìs. 35 seminarist ühe viis läbi Tartu Noorte Loodusmaja geoloogia ja keskkonnaringi esindus, tutvustati loodusmaja keskkonnaprojekte ja räägiti keskkonnaalaste veebilehtede koostamise kogemustest. YouthCaN (Youth Communicating and Networking) on rahvusvaheline noorte organisatsioon, mis vahendab kogemusi ja uusi ideid elukeskkonnast huvitatud noorte hulgas

  20. Density structure of the cratonic mantle in southern Africa

    DEFF Research Database (Denmark)

    Artemieva, Irina; Vinnik, Lev P.

    2016-01-01

    contributions of the both factors to surface topography in the cratons of southern Africa. Our analysis takes advantage of the SASE seismic experiment which provided high resolution regional models of the crustal thickness.We calculate the model of density structure of the lithospheric mantle in southern Africa...... that mantle residual (dynamic) topography may be associated with the low-density region below the depth of isostatic compensation. A possible candidate is the low velocity layer between the lithospheric base and the mantle transition zone, where a temperature anomaly of 100-200. °C in a ca. 100-150. km thick...... layer may explain the observed reduction in Vs velocity and may produce ca. 0.5-1.0. km to the regional topographic uplift....

  1. Giant monopole transition densities within the local scale ATDHF approach

    International Nuclear Information System (INIS)

    Dimitrova, S.S.; Petkov, I.Zh.; Stoitsov, M.V.

    1986-01-01

    Transition densities for 12 C, 16 O, 28 Si, 32 S, 40 Ca, 48 Ca, 56 Ni, 90 Zr, 208 Pb even-even nuclei corresponding to nuclear glant monopole resonances obtained within a local-scale adiabatic time-dependent Hartree-Fook approach in terms of effective Skyrme-type forces SkM and S3. The approach, the particular form and all necessary coefficients of these transition densities are reported. They are of a simple analytical form and may be directly used for example in analyses of particle inelastic scattering on nuclei by distorted wave method and a such a way allowing a test of the theoretical interpretation of giant monopole resonances

  2. Ion-microprobe measurements of Mg, Ca, Ti and Fe isotopic ratios and trace element abundance in hibonite-bearing inclusions in primitive meteorites

    International Nuclear Information System (INIS)

    Fahey, A.J.

    1988-01-01

    This thesis reports the isotopic abundances of Mg, Ca, and Ti and rare earth element (REE) abundances in 19 hibonite-bearing inclusions from primative meteorites. The isotopic ratios of Fe were measured in one of the samples, Lance HH-1. These measurements were made by means of secondary ion mass spectrometry (CAMECA IMS-3f). The novel hardware and software developments that made this work possible are described in detail. The samples were studied in thin section in order to investigate the relationship between the inclusions and their mineralogical environments. Inclusions from a number of different meteorites, specifically, Mighei, Murray, Murchison, Lance, Efremovka, Vigarano, Qingzhen, Dhajala, and Semarkona, were studied. The isotopes of Ca and Ti show large and correlated abundance anomalies in their most neutron-rich isotopes, 48 Ca and 50 Ti. The largest anomalies among the samples studied here are in the Murray inclusion MY-F6, with a 4.6% deficit in 48 Ca and a 5.2% deficit in 50 Ti, and Lance HH-1, with 3.3% and 6.0% deficits in 48 Ca and 50 Ti respectively. Correlated excesses of 48 Ca and 50 Ti, up to 2.4% and 1.4% respectively, are found in some other samples studied here. The fact that there is a correlation of isotopic anomalies in two different elements is clear evidence for a nucleosynthetic origin of these effects. Various possibilities for the origin of these isotopic anomalies are discussed and it is shown that a Cosmic Chemical Memory-like model of the incomplete mixing of dust grains from one or several supernovae is sufficient to explain the data. Magnesium isotopes show excesses of 26 Mg, attributable to the in-situ decay of 26 Al, in 7 of these inclusions

  3. Transcriptional upregulation of α2δ-1 elevates arterial smooth muscle cell voltage-dependent Ca2+ channel surface expression and cerebrovascular constriction in genetic hypertension.

    Science.gov (United States)

    Bannister, John P; Bulley, Simon; Narayanan, Damodaran; Thomas-Gatewood, Candice; Luzny, Patrik; Pachuau, Judith; Jaggar, Jonathan H

    2012-10-01

    A hallmark of hypertension is an increase in arterial myocyte voltage-dependent Ca2+ (CaV1.2) currents that induces pathological vasoconstriction. CaV1.2 channels are heteromeric complexes composed of a pore-forming CaV1.2α1 with auxiliary α2δ and β subunits. Molecular mechanisms that elevate CaV1.2 currents during hypertension and the potential contribution of CaV1.2 auxiliary subunits are unclear. Here, we investigated the pathological significance of α2δ subunits in vasoconstriction associated with hypertension. Age-dependent development of hypertension in spontaneously hypertensive rats was associated with an unequal elevation in α2δ-1 and CaV1.2α1 mRNA and protein in cerebral artery myocytes, with α2δ-1 increasing more than CaV1.2α1. Other α2δ isoforms did not emerge in hypertension. Myocytes and arteries of hypertensive spontaneously hypertensive rats displayed higher surface-localized α2δ-1 and CaV1.2α1 proteins, surface α2δ-1:CaV1.2α1 ratio, CaV1.2 current density and noninactivating current, and pressure- and depolarization-induced vasoconstriction than those of Wistar-Kyoto controls. Pregabalin, an α2δ-1 ligand, did not alter α2δ-1 or CaV1.2α1 total protein but normalized α2δ-1 and CaV1.2α1 surface expression, surface α2δ-1:CaV1.2α1, CaV1.2 current density and inactivation, and vasoconstriction in myocytes and arteries of hypertensive rats to control levels. Genetic hypertension is associated with an elevation in α2δ-1 expression that promotes surface trafficking of CaV1.2 channels in cerebral artery myocytes. This leads to an increase in CaV1.2 current-density and a reduction in current inactivation that induces vasoconstriction. Data also suggest that α2δ-1 targeting is a novel strategy that may be used to reverse pathological CaV1.2 channel trafficking to induce cerebrovascular dilation in hypertension.

  4. Introduction of the rd29A: AtDREB2A CA gene into soybean (Glycine max L. Merril and its molecular characterization in leaves and roots during dehydration

    Directory of Open Access Journals (Sweden)

    Cibelle Engels

    2013-01-01

    Full Text Available The loss of soybean yield to Brazilian producers because of a water deficit in the 2011-2012 season was 12.9%. To reduce such losses, molecular biology techniques, including plant transformation, can be used to insert genes of interest into conventional soybean cultivars to produce lines that are more tolerant to drought. The abscisic acid (ABA-independent Dehydration Responsive Element Binding (DREB gene family has been used to obtain plants with increased tolerance to abiotic stresses. In the present study, the rd29A:AtDREB2A CA gene from Arabidopsis thaliana was inserted into soybean using biolistics. Seventy-eight genetically modified (GM soybean lines containing 2-17 copies of the AtDREB2A CA gene were produced. Two GM soybean lines (P1397 and P2193 were analyzed to assess the differential expression of the AtDREB2A CA transgene in leaves and roots submitted to various dehydration treatments. Both GM lines exhibited high expression of the transgene, with the roots of P2193 showing the highest expression levels during water deficit. Physiological parameters examined during water deficit confirmed the induction of stress. This analysis of AtDREB2A CA expression in GM soybean indicated that line P2193 had the greatest stability and highest expression in roots during water deficit-induced stress.

  5. Quantal density functional theory

    CERN Document Server

    Sahni, Viraht

    2016-01-01

    This book deals with quantal density functional theory (QDFT) which is a time-dependent local effective potential theory of the electronic structure of matter. The treated time-independent QDFT constitutes a special case. In the 2nd edition, the theory is extended to include the presence of external magnetostatic fields. The theory is a description of matter based on the ‘quantal Newtonian’ first and second laws which is in terms of “classical” fields that pervade all space, and their quantal sources. The fields, which are explicitly defined, are separately representative of electron correlations due to the Pauli exclusion principle, Coulomb repulsion, correlation-kinetic, correlation-current-density, and correlation-magnetic effects. The book further describes Schrödinger theory from the new physical perspective of fields and quantal sources. It also describes traditional Hohenberg-Kohn-Sham DFT, and explains via QDFT the physics underlying the various energy functionals and functional derivatives o...

  6. Discrete density of states

    International Nuclear Information System (INIS)

    Aydin, Alhun; Sisman, Altug

    2016-01-01

    By considering the quantum-mechanically minimum allowable energy interval, we exactly count number of states (NOS) and introduce discrete density of states (DOS) concept for a particle in a box for various dimensions. Expressions for bounded and unbounded continua are analytically recovered from discrete ones. Even though substantial fluctuations prevail in discrete DOS, they're almost completely flattened out after summation or integration operation. It's seen that relative errors of analytical expressions of bounded/unbounded continua rapidly decrease for high NOS values (weak confinement or high energy conditions), while the proposed analytical expressions based on Weyl's conjecture always preserve their lower error characteristic. - Highlights: • Discrete density of states considering minimum energy difference is proposed. • Analytical DOS and NOS formulas based on Weyl conjecture are given. • Discrete DOS and NOS functions are examined for various dimensions. • Relative errors of analytical formulas are much better than the conventional ones.

  7. Discrete density of states

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Alhun; Sisman, Altug, E-mail: sismanal@itu.edu.tr

    2016-03-22

    By considering the quantum-mechanically minimum allowable energy interval, we exactly count number of states (NOS) and introduce discrete density of states (DOS) concept for a particle in a box for various dimensions. Expressions for bounded and unbounded continua are analytically recovered from discrete ones. Even though substantial fluctuations prevail in discrete DOS, they're almost completely flattened out after summation or integration operation. It's seen that relative errors of analytical expressions of bounded/unbounded continua rapidly decrease for high NOS values (weak confinement or high energy conditions), while the proposed analytical expressions based on Weyl's conjecture always preserve their lower error characteristic. - Highlights: • Discrete density of states considering minimum energy difference is proposed. • Analytical DOS and NOS formulas based on Weyl conjecture are given. • Discrete DOS and NOS functions are examined for various dimensions. • Relative errors of analytical formulas are much better than the conventional ones.

  8. Density dependent effective interactions

    International Nuclear Information System (INIS)

    Dortmans, P.J.; Amos, K.

    1994-01-01

    An effective nucleon-nucleon interaction is defined by an optimal fit to select on-and half-off-of-the-energy shell t-and g-matrices determined by solutions of the Lippmann-Schwinger and Brueckner-Bethe-Goldstone equations with the Paris nucleon-nucleon interaction as input. As such, it is seen to better reproduce the interaction on which it is based than other commonly used density dependent effective interactions. The new (medium modified) effective interaction when folded with appropriate density matrices, has been used to define proton- 12 C and proton- 16 O optical potentials. With them elastic scattering data are well fit and the medium effects identifiable. 23 refs., 8 figs

  9. Arabidopsis PCaP2 Functions as a Linker Between ABA and SA Signals in Plant Water Deficit Tolerance

    Directory of Open Access Journals (Sweden)

    Xianling Wang

    2018-05-01

    Full Text Available Water stress has a major influence on plant growth, development, and productivity. However, the cross-talk networks involved in drought tolerance are not well understood. Arabidopsis PCaP2 is a plasma membrane-associated Ca2+-binding protein. In this study, we employ qRT-PCR and β-glucuronidase (GUS histochemical staining to demonstrate that PCaP2 expression was strongly induced in roots, cotyledons, true leaves, lateral roots, and whole plants under water deficit conditions. Compared with the wild type (WT plants, PCaP2-overexpressing (PCaP2-OE plants displayed enhanced water deficit tolerance in terms of seed germination, seedling growth, and plant survival status. On the contrary, PCaP2 mutation and reduction via PCaP2-RNAi rendered plants more sensitive to water deficit. Furthermore, PCaP2-RNAi and pcap2 seedlings showed shorter root hairs and lower relative water content compared to WT under normal conditions and these phenotypes were exacerbated under water deficit. Additionally, the expression of PCaP2 was strongly induced by exogenous abscisic acid (ABA and salicylic acid (SA treatments. PCaP2-OE plants showed insensitive to exogenous ABA and SA treatments, in contrast to the susceptible phenotypes of pcap2 and PCaP2-RNAi. It is well-known that SNF1-related kinase 2s (SnRK2s and pathogenesis-related (PRs are major factors that influence plant drought tolerance by ABA- and SA-mediated pathways, respectively. Interestingly, PCaP2 positively regulated the expression of drought-inducible genes (RD29A, KIN1, and KIN2, ABA-mediated drought responsive genes (SnRK2.2, -2.3, -2.6, ABF1, -2, -3, -4, and SA-mediated drought responsive genes (PR1, -2, -5 under water deficit, ABA, or SA treatments. Taken together, our results showed that PCaP2 plays an important and positive role in Arabidopsis water deficit tolerance by involving in response to both ABA and SA signals and regulating root hair growth. This study provides novel insights into the

  10. Prepotent response inhibition predicts treatment outcome in attention deficit/hyperactivity disorder

    NARCIS (Netherlands)

    van der Oord, S.; Geurts, H.M.; Prins, P.J.M.; Emmelkamp, P.M.G.; Oosterlaan, J.

    2012-01-01

    Objective: Inhibition deficits, including deficits in prepotent response inhibition and interference control, are core deficits in ADHD. The predictive value of prepotent response inhibition and interference control was assessed for outcome in a 10-week treatment trial with methylphenidate. Methods:

  11. Variable Kernel Density Estimation

    OpenAIRE

    Terrell, George R.; Scott, David W.

    1992-01-01

    We investigate some of the possibilities for improvement of univariate and multivariate kernel density estimates by varying the window over the domain of estimation, pointwise and globally. Two general approaches are to vary the window width by the point of estimation and by point of the sample observation. The first possibility is shown to be of little efficacy in one variable. In particular, nearest-neighbor estimators in all versions perform poorly in one and two dimensions, but begin to b...

  12. Density oscillations within hadrons

    International Nuclear Information System (INIS)

    Arnold, R.; Barshay, S.

    1976-01-01

    In models of extended hadrons, in which small bits of matter carrying charge and effective mass exist confined within a medium, oscillations in the matter density may occur. A way of investigating this possibility experimentally in high-energy hadron-hadron elastic diffraction scattering is suggested, and the effect is illustrated by examining some existing data which might be relevant to the question [fr

  13. Inflectional spelling deficits in developmental dyslexia.

    Science.gov (United States)

    Egan, Joanne; Tainturier, Marie-Josèphe

    2011-01-01

    The goal of this study was to examine past-tense spelling deficits in developmental dyslexia and their relationship to phonological abilities, spoken morphological awareness and word specific orthographic memory. Three groups of children (28 9-year-old dyslexic, 28 chronological age-matched and 28 reading/spelling age-matched children) completed a battery of tests including spelling regularly inflected words (e.g., kissed) and matched one-morpheme words (e.g., wrist). They were also assessed on a range of tests of reading and spelling abilities and associated linguistic measures. Dyslexic children were impaired in relation to chronological age-matched controls on all measures. Furthermore, they were significantly poorer than younger reading and spelling age-matched controls at spelling inflected verbs, supporting the existence of a specific deficit in past-tense spelling in dyslexia. In addition to under-using the -ed spelling on inflected verbs, the dyslexic children were less likely to erroneously apply this spelling to one-morpheme words than younger controls. Dyslexics were also poorer than younger controls at using a consistent spelling for stems presented in isolation versus as part of an inflected word, indicating that they make less use of the morphological relations between words to support their spelling. In line with this interpretation, regression analyses revealed another qualitative difference between the spelling and reading age-matched group and the dyslexic group: while both spoken morphological awareness and orthographic word specific memory were significant predictors of the accuracy of past-tense spelling in the former group, only orthographic memory (irregular word reading and spelling) was a significant factor in the dyslexic group. Finally, we identified a subgroup of seven dyslexic children who were severely deficient in past-tense spelling. This subgroup was also significantly worse than other dyslexics and than younger controls on scores

  14. Can Latin America fill the U.S. polyolefin deficit?

    International Nuclear Information System (INIS)

    Sagel, E.

    2006-01-01

    Strategic issues for the North American polyolefin industry were discussed with reference to oil and gas price forecasts, oil capacity increases, and high density polyethylene production and ethylene integration costs. The overall polyolefin trade balance in North America was also explored. It was cautioned that unless a significant amount of new capacity is built in the United States, it is anticipated that by 2008, the United States will become a net importer of polyolefin resins. Currently exported product will be used increasingly in the domestic market to meet demand growth. This shift from being a net exporter of resins can be attributed to the high cost of feedstocks and the lack of investment in new capacity throughout the region. In contrast, there have been several proposals for new capacity in Latin America in the past several years. Since there is already an important level of commerce and trade between North and South America, countries with access to the Caribbean basin, are logistically well situated to serve the North American market. The availability of low cost feedstocks in countries such as Trinidad, Venezuela and Bolivia add to the attractiveness of the region for the development of new petrochemical capacity. This paper examined the status of the different proposed projects in Latin America and analyzed the potential opportunities that exist for North American producers to collaborate in those projects. The general trade balance of the continent was reviewed in order to verify if the traditional seclusion of America's polyolefin market can be maintained in the future. It was concluded that even if all projects in Latin America are launched, the Americas will still be in a net deficit position. Under the right circumstances, the Middle East will be the global supplier of commodity polyolefins that could extend to the Americas. It was emphasized that companies should be prepared for feedstock advantaged investments, alliances, acquisitions and

  15. Study on the isospin equilibration phenomenon in nuclear reactions 40Ca + 40Ca , 40Ca + 46Ti , 40Ca + 48Ca , 48Ca + 48Ca at 25 MeV/nucleon by using the CHIMERA multidetector

    Science.gov (United States)

    Martorana, N. S.; Auditore, L.; Berceanu, I.; Cardella, G.; Chatterjee, M. B.; De Luca, S.; De Filippo, E.; Dell'Aquila, D.; Gnoffo, B.; Lanzalone, G.; Lombardo, I.; Maiolino, C.; Norella, S.; Pagano, A.; Pagano, E. V.; Papa, M.; Pirrone, S.; Politi, G.; Porto, F.; Quattrocchi, L.; Rizzo, F.; Russotto, P.; Trifirò, A.; Trimarchi, M.; Verde, G.; Vigilante, M.

    2017-11-01

    We report on the results obtained by studying nuclear reactions between isotopes of Ca and Ti at 25 MeV/nucleon. We used the multidetector CHIMERA to detect charged reaction products. In particular, we studied two main effects: the isospin diffusion and the isospin drift. In order to study these processes we performed a moving-source analysis on kinetic energy spectra of the isobar nuclei ^{3H} and ^{3He} . This method allows to isolate the emission from the typical sources produced in reactions at Fermi energy: projectile like fragment (PLF), target like fragment (TLF), and mid-velocity (MV) emission. The obtained results are compared to previous experimental investigations and to simulations obtained with CoMD-II model.

  16. Effects of Synthesis and Spark Plasma Sintering Conditions on the Thermoelectric Properties of Ca3Co4O9+δ

    DEFF Research Database (Denmark)

    Wu, NingYu; Holgate, Tim; Van Nong, Ngo

    2013-01-01

    Ca3Co4O9+δ samples were synthesized by solid-state (SS) and sol–gel (SG) reactions, followed by spark plasma sintering under different processing conditions. The synthesis process was optimized and the resulting materials characterized with respect to their microstructure, bulk density, and therm......Ca3Co4O9+δ samples were synthesized by solid-state (SS) and sol–gel (SG) reactions, followed by spark plasma sintering under different processing conditions. The synthesis process was optimized and the resulting materials characterized with respect to their microstructure, bulk density...

  17. Mineral density volume gradients in normal and diseased human tissues.

    Directory of Open Access Journals (Sweden)

    Sabra I Djomehri

    Full Text Available Clinical computed tomography provides a single mineral density (MD value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca to phosphorus (P and Ca to zinc (Zn elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males contained significant mineral density variations (enamel: 2820-3095 mg/cc, bone: 570-1415 mg/cc, cementum: 1240-1340 mg/cc, dentin: 1480-1590 mg/cc, cementum affected by periodontitis: 1100-1220 mg/cc, hypomineralized carious dentin: 345-1450 mg/cc, hypermineralized carious dentin: 1815-2740 mg/cc, and dental calculus: 1290-1770 mg/cc. A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49, hypomineralized dentin (0.32-0.46, cementum (1.51, and bone (1.68 were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765 and in cementum (595-990, highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations.

  18. Mineral Density Volume Gradients in Normal and Diseased Human Tissues

    Science.gov (United States)

    Djomehri, Sabra I.; Candell, Susan; Case, Thomas; Browning, Alyssa; Marshall, Grayson W.; Yun, Wenbing; Lau, S. H.; Webb, Samuel; Ho, Sunita P.

    2015-01-01

    Clinical computed tomography provides a single mineral density (MD) value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca) to phosphorus (P) and Ca to zinc (Zn) elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT) benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF) using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males) contained significant mineral density variations (enamel: 2820-3095mg/cc, bone: 570-1415mg/cc, cementum: 1240-1340mg/cc, dentin: 1480-1590mg/cc, cementum affected by periodontitis: 1100-1220mg/cc, hypomineralized carious dentin: 345-1450mg/cc, hypermineralized carious dentin: 1815-2740mg/cc, and dental calculus: 1290-1770mg/cc). A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49), hypomineralized dentin (0.32-0.46), cementum (1.51), and bone (1.68) were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765) and in cementum (595-990), highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations. PMID:25856386

  19. Vitamin D Deficiency and a Blunted Parathyroid Hormone Response in Children with Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Avcil, Sibelnur; Uysal, Pinar; Yilmaz, Mustafa; Erge, Duygu; Demirkaya, Sevcan K; Eren, Esra

    2017-03-01

    Attention-deficit/hyperactivity disorder (ADHD) is the most frequently diagnosed neuropsychiatric disorder of childhood. The etiopathogenesis of ADHD has not been fully defined. Recent evidence has suggested a pathophysiological role of vitamin D deficiency in ADHD. In this study, we evaluated the serum levels of 25-hydroxy vitamin D (25(OH)D), parathyroid hormone (PTH), calcium (Ca), phosphate (P), and alkaline phosphatase (ALP) in children with ADHD. The study group consisted of 105 children diagnosed with ADHD according to DSM-IV-TR criteria. A control group, matched for age and gender, was composed of 95 healthy children. Venous blood samples were collected, and 25(OH)D, PTH, Ca, P, and ALP levels were measured. The mean serum 25(OH)D, Ca, and P levels of the children with ADHD were significantly lower than those of the healthy controls. There were no significant differences between the groups regarding PTH and ALP. Serum PTH levels were found to be normal, but vitamin D deficiency, hypocalcemia, and hypophosphatemia were observed in children with ADHD. There was no correlation between serum PTH and Ca levels in children with ADHD, whereas, there was a negative correlation between serum PTH and Ca levels in healthy controls. There was no correlation between serum 25(OH)D and PTH levels in children with ADHD, whereas, there was a negative correlation between serum 25(OH)D and PTH levels in healthy controls. There were no significant differences in all parameters' levels among the subtypes of ADHD. The findings suggest that ADHD is associated with vitamin D deficiency, blunted PTH response, and impaired Ca homeostasis in children.

  20. Toward a Redefinition of Density

    Science.gov (United States)

    Rapoport, Amos

    1975-01-01

    This paper suggests that in addition to the recent work indicating that crowding is a subjective phenomenon, an adequate definition of density must also include a subjective component since density is a complex phenomenon in itself. Included is a discussion of both physical density and perceived density. (Author/MA)

  1. Density measures and additive property

    OpenAIRE

    Kunisada, Ryoichi

    2015-01-01

    We deal with finitely additive measures defined on all subsets of natural numbers which extend the asymptotic density (density measures). We consider a class of density measures which are constructed from free ultrafilters on natural numbers and study a certain additivity property of such density measures.

  2. Motor skill learning and offline-changes in TGA patients with acute hippocampal CA1 lesions.

    Science.gov (United States)

    Döhring, Juliane; Stoldt, Anne; Witt, Karsten; Schönfeld, Robby; Deuschl, Günther; Born, Jan; Bartsch, Thorsten

    2017-04-01

    Learning and the formation of memory are reflected in various memory systems in the human brain such as the hippocampus based declarative memory system and the striatum-cortex based system involved in motor sequence learning. It is a matter of debate how both memory systems interact in humans during learning and consolidation and how this interaction is influenced by sleep. We studied the effect of an acute dysfunction of hippocampal CA1 neurons on the acquisition (on-line condition) and off-line changes of a motor skill in patients with a transient global amnesia (TGA). Sixteen patients (68 ± 4.4 yrs) were studied in the acute phase and during follow-up using a declarative and procedural test, and were compared to controls. Acute TGA patients displayed profound deficits in all declarative memory functions. During the acute amnestic phase, patients were able to acquire the motor skill task reflected by increasing finger tapping speed across the on-line condition, albeit to a lesser degree than during follow-up or compared to controls. Retrieval two days later indicated a greater off-line gain in motor speed in patients than controls. Moreover, this gain in motor skill performance was negatively correlated to the declarative learning deficit. Our results suggest a differential interaction between procedural and declarative memory systems during acquisition and consolidation of motor sequences in older humans. During acquisition, hippocampal dysfunction attenuates fast learning and thus unmasks the slow and rigid learning curve of striatum-based procedural learning. The stronger gains in the post-consolidation condition in motor skill in CA1 lesioned patients indicate a facilitated consolidation process probably occurring during sleep, and suggest a competitive interaction between the memory systems. These findings might be a reflection of network reorganization and plasticity in older humans and in the presence of CA1 hippocampal pathology. Copyright © 2016

  3. Ca(2+-dependent regulation of the Ca(2+ concentration in the myometrium mitochondria. II. Ca(2+ effects on mitochondria membranes polarization and [Ca(2+](m

    Directory of Open Access Journals (Sweden)

    L. G. Babich

    2017-06-01

    Full Text Available It is known that Ca2+ accumulation in the mitochondria undergoes complex regulation by Ca2+ itself. But the mechanisms of such regulation are still discussed. In this paper we have shown that Ca ions directly or indirectly regulate the level of myometrium mitochondria membranes polarization. The additions of 100 µM Ca2+ were accompanied by depolarization of the mitochondria membranes. The following experiments were designed to study the impact of Ca2+ on the myometrium mitochondria [Ca2+]m. Isolated myometrium mitochondria were preincubated without or with 10 μM Са2+ followed by 100 μM Са2+ addition. Experiments were conducted in three mediums: without ATP and Mg2+ (0-medium, in the presence of 3 mM Mg2+ (Mg-medium and 3 mM Mg2+ + 3 mM ATP (Mg,ATP-medium. It was shown that the effects of 10 μM Са2+ addition were different in different mediums, namely in 0- and Mg-medium the [Ca2+]m values increased, whereas in Mg,ATP-medium statistically reliable changes were not registered. Preincubation of mitochondria with 10 μM Са2+ did not affect the [Ca2+]m value after the addition of 100 μM Са2+. The [Ca2+]m values after 100 μM Са2+ addition were the same in 0- and Mg,ATP-mediums and somewhat lower in Mg-medium. Preliminary incubation of mitochondria with 10 μM Са2+ in 0- and Mg-mediums reduced changes of Fluo 4 normalized fluorescence values that were induced by 100 μM Са2+ additions, but in Mg,ATP-medium such differences were not recorded. It is concluded that Са2+ exchange in myometrium mitochondria is regulated by the concentration of Ca ions as in the external medium, so in the matrix of mitochondria. The medium composition had a significant impact on the [Са2+]m values in the absence of exogenous cation. It is suggested that light increase of [Са2+]m before the addition of 100 μM Са2+ may have a positive effect on the functional activity of the mitochondria.

  4. Ricardian Equivalence, Twin Deficits, and the Feldstein-Horioka puzzle in Egypt

    OpenAIRE

    Carlos Marinheiro

    2006-01-01

    Egypt has presented important budget imbalances. This paper tries to evaluate whether Egypt’s public deficit has had any impact on current account imbalances, examining the validity of the twin deficit hypothesis for Egypt. We conclude for the presence of a (weak) long-run relationship between the budget deficit and the current account deficit. Yet, we reject the twin-deficit hypothesis: we found evidence in favour of a reverse Granger-causality running from the external deficit to the budget...

  5. Influence of ER leak on resting cytoplasmic Ca2+ and receptor-mediated Ca2+ signalling in human macrophage.

    Science.gov (United States)

    Layhadi, Janice A; Fountain, Samuel J

    2017-06-03

    Mechanisms controlling endoplasmic reticulum (ER) Ca 2+ homeostasis are important regulators of resting cytoplasmic Ca 2+ concentration ([Ca 2+ ] cyto ) and receptor-mediated Ca 2+ signalling. Here we investigate channels responsible for ER Ca 2+ leak in THP-1 macrophage and human primary macrophage. In the absence of extracellular Ca 2+ we employ ionomycin action at the plasma membrane to stimulate ER Ca 2+ leak. Under these conditions ionomycin elevates [Ca 2+ ] cyto revealing a Ca 2+ leak response which is abolished by thapsigargin. IP 3 receptors (Xestospongin C, 2-APB), ryanodine receptors (dantrolene), and translocon (anisomycin) inhibition facilitated ER Ca 2+ leak in model macrophage, with translocon inhibition also reducing resting [Ca 2+ ] cyto . In primary macrophage, translocon inhibition blocks Ca 2+ leak but does not influence resting [Ca 2+ ] cyto . We identify a role for translocon-mediated ER Ca 2+ leak in receptor-mediated Ca 2+ signalling in both model and primary human macrophage, whereby the Ca 2+ response to ADP (P2Y receptor agonist) is augmented following anisomycin treatment. In conclusion, we demonstrate a role of ER Ca 2+ leak via the translocon in controlling resting cytoplasmic Ca 2+ in model macrophage and receptor-mediated Ca 2+ signalling in model macrophage and primary macrophage. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Regulation of Blood Pressure by Targeting CaV1.2-Galectin-1 Protein Interaction.

    Science.gov (United States)

    Hu, Zhenyu; Li, Guang; Wang, Jiong-Wei; Chong, Suet Yen; Yu, Dejie; Wang, Xiaoyuan; Soon, Jia Lin; Liang, Mui Cheng; Wong, Yuk Peng; Huang, Na; Colecraft, Henry M; Liao, Ping; Soong, Tuck Wah

    2018-04-12

    Background -L-type Ca V 1.2 channels play crucial roles in regulation of blood pressure. Galectin-1 (Gal-1), has been reported to bind to the I-II loop of Ca V 1.2 channels to reduce their current density. However, the mechanistic understanding for the down-regulation of Ca V 1.2 channels by Gal-1, and whether Gal-1 plays a direct role in blood pressure regulation remain unclear. Methods - In vitro experiments involving co-IP, western blot, patch-clamp recordings, immunohistochemistry and pressure myography were used to evaluate the molecular mechanisms by which Gal-1 down-regulates Ca V 1.2 channel in transfected HEK 293 cells, smooth muscle cells, arteries from Lgasl1 -/- mice, rat and human patients. In vivo experiments involving delivery of Tat-e9c peptide and AAV5-Gal-1 into rats were performed to investigate the effect of targeting Ca V 1.2-Gal-1 interaction on blood pressure monitored by tail cuff or telemetry methods. Results -Our study reveals that Gal-1 is a key regulator for proteasomal degradation of Ca V 1.2 channels. Gal-1 competed allosterically with Ca V β subunit for binding to the I-II loop of Ca V 1.2 channel. This competitive disruption of Ca V β binding led to Ca V 1.2 degradation by exposing the channels to poly-ubiquitination. Notably, we demonstrated that the inverse relationship of reduced Gal-1 and increased Ca V 1.2 protein levels in arteries was associated with hypertension in hypertensive rats and patients, and Gal-1 deficiency induces higher blood pressure in mice due to up-regulated Ca V 1.2 protein level in arteries. To directly regulate blood pressure by targeting the Ca V 1.2-Gal-1 interaction, we administered Tat-e9c, a peptide that competed for binding of Gal-1, by a mini-osmotic pump and this specific disruption of Ca V 1.2-Gal-1 coupling increased smooth muscle Ca V 1.2 currents, induced larger arterial contraction and caused hypertension in rats. In contrasting experiments, over-expression of Gal-1 in smooth muscle by a

  7. Airway somatosensory deficits and dysphagia in Parkinson's disease.

    Science.gov (United States)

    Hammer, Michael J; Murphy, Caitlin A; Abrams, Trisha M

    2013-01-01

    Individuals with Parkinson's disease (PD) often experience substantial impairment of swallow control, and are typically unaware of the presence or severity of their impairments suggesting that these individuals may also experience airway sensory deficits. However, the degree to which impaired swallow function in PD may relate to airway sensory deficits has yet to be formally tested. The purpose of this study was to examine whether airway sensory function is associated with swallow impairment in PD. Eighteen PD participants and 18 healthy controls participated in this study and underwent endoscopic assessment of airway somatosensory function, endoscopic assessment of swallow function, and clinical ratings of swallow and disease severity. PD participants exhibited abnormal airway somatosensory function and greater swallow impairment compared with healthy controls. Swallow and sensory deficits in PD were correlated with disease severity. Moreover, PD participants reported similar self-rated swallow function as healthy controls, and swallow deficits were correlated with sensory function suggesting an association between impaired sensory function and poor self-awareness of swallow deficits in PD. These results suggest that control of swallow is influenced by airway somatosensory function, that swallow-related deficits in PD are related to abnormal somatosensation, and that swallow and airway sensory function may degrade as a function of disease severity. Therefore, the basal ganglia and related neural networks may play an important role to integrate airway sensory input for swallow-related motor control. Furthermore, the airway deficits observed in PD suggest a disintegration of swallow-related sensory and motor control.

  8. Understanding the centrality deficit: insight from foreign language learners.

    Science.gov (United States)

    Miller, Amanda C; Keenan, Janice M

    2011-07-01

    This study replicated and extended a phenomenon in the text memory literature referred to as the centrality deficit Miller & Keenan (Annals of Dyslexia 59:99-113, 2009). It examined how reading in a foreign language (L2) affects one's text representation and ability to recall the most important information. Readers recalled a greater proportion of central than of peripheral ideas, regardless of whether reading in their native language (L1) or a foreign language (L2). Nonetheless, the greatest deficit in participants' L2 recalls, as compared with L1 recalls, was on the central, rather than the peripheral, information. This centrality deficit appears to stem from resources being diverted from comprehension when readers have to devote more cognitive resources to lower level processes (e.g., L2 word identification and syntactic processing), because the deficit was most evident among readers who had lower L2 proficiency. Prior knowledge (PK) of the passage topic helped compensate for the centrality deficit. Readers with less L2 proficiency who did not have PK of the topic displayed a centrality deficit, relative to their L1 recall, but this deficit dissipated when they did possess PK.

  9. CT findings predictive of neurological deficits in throracolumbar burst fractures

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Tae Yong; Jeong, Hee Seok; Jeong, Yeo Jin [Pusan National University and Research Institute for Convergence of Biomedical Science and Technology, Dept. of Radiology, Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of); Lee, In Sook [Dept. of Radiology, Pusan National University Hospital, Busan (Korea, Republic of)

    2016-09-15

    To determine the computed tomography (CT) findings predictive of neurological deficits in thoracolumbar spine injuries. One hundred two patients with thoracolumbar spinal burst fractures, after excluding the patients with brain and cervical cord injuries and unconsciousness, who underwent consecutive spine 128-multidetector CT scan formed the study group. The neurological findings were clinically classified as no deficit (n = 58), complete deficit with paraplegia (n = 22), and incomplete deficit with either motor or sensory impairment (n = 22). The following four CT imaging parameters were analyzed: the level of the main burst fracture as the cord (n = 44) and the cauda equina (n = 58) levels; the extent of canal encroachment as central canal ratios (CCRs) below 0.5 (n = 43) and above 0.5 (n = 59); the degree of laminar fracture as no fracture (n = 33), linear fracture (n = 7), separated fracture (n = 27), and displaced fracture (n = 35); fractured vertebra counted as single (n = 53) and multiple (n = 49). Complete neurological deficit was associated with injuries at the cord level (p = 0.000) and displaced laminar fractures (p = 0.000); incomplete neurological deficit was associated with CCRs below 0.5 (p = 0.000) and multiple vertebral injuries (p = 0.002). CT scan can provide additional findings predictive of neurological deficits in thoracolumbar spinal burst fractures.

  10. The Pr and Ca Substitution in GdBa2Cu3O7- & delta

    Directory of Open Access Journals (Sweden)

    H. S. H.

    2001-12-01

    Full Text Available   The granular Gd1-x-zPrxCazBa2Cu3O7-δ high-temperature cuprate samples with 0.0 ≤ x ≤ 0.3 and 0.0≤ x ≤ 0.35 are prepared by standard solid state reaction and characterized by XRD and SEM techniques. The BaCuO2 and impurity phases are less than 1% in the samples having high levels of pr and Ca concentrations. The electrical resistivity measurements show a nonlinear reduction in Tc(x,z=etc versus x. Moreover, the Tc(z curve with x=0 is nonlinear and aplateau appears at z≈ 0.05-0.015. For Pr-Ca-doped samples with a constant concentration of Pr, Tc increases with the increase of Ca up to an optimum value of Ca doping and then in decreases. Based on these observations, we suggest that hole filling and hole localization the main effects of Pr ion substiution. The magnetic measurements indicate that the value of Hc1 is in the order of 10 mT. The mangetoresistance measurements have been measured and analyzed. The superconducting transition region is broadened by the application of magnetic field. The experimental data near the onsen of superconductivity are fitted with the Ambegakor and Halperin (AH phase-slip model. We observe that the AH parameter,γ (H, depends not only on the temperature and the magnetic field, but also on the Pr and Ca ions concentrations. It is observed that the critical current density increases with Ca substitution and decreases with Pr substitution in Gd-123 system. We suggest that the Pr ion substitution probably enhances the weak link, but the Ca ion acts as flux pinning center in the GdPrCa-123 system.

  11. Study on 41Ca-AMS for diagnosis and assessment of cancer bone metastasis in rats

    International Nuclear Information System (INIS)

    Shen, Hongtao; Pang, Fangfang; Jiang, Shan; He, Ming; Dong, Kejun; Dou, Liang; Pang, Yijun; Yang, Xianlin; Ruan, Xiangdong; Liu, Manjun; Xia, Chunbo

    2015-01-01

    The annual incidence of new cancer patients in China is about 2 million, 30–40% of which will end up with bone metastasis. Profound study on the preclinical model and early diagnosis of cancer bone metastasis in rats are very significant for the drug development, better understanding and treatment of bone metastases. In order to monitor the process of bone metabolism and early detection of bone metastasis of cancer cells, a technique of 41 Ca isotope tracer combined with AMS has been developed and applied in the study on the bone metastasis of cancer cells by rat model. In this work, 3-month-old female Sprague–Dawley (SD) rats were randomly divided into different groups, and tumor cells injected respectively into the tail vein, femoral artery, femoral cavity and the thigh muscle to establish the rat models for bone metastases. The most appropriate model, i.e., the thigh muscle group, was finally adopted in our real metastases experiment. Each rat in this group was intramuscularly (i.m.) injected with 250 μl CaCl 2 solution (containing 1.4 mg Ca and 5nCi 41 Ca). About 40 days later, the rat mammary gland carcinoma cells (Walker 256) were injected into these rats following the established protocol. After bone metastasis, medicine interventions were performed. The sequential urine and blood samples were collected and analyzed for 41 Ca (by AMS) and N-terminal telopeptide (Ntx), respectively. Bone Mineral Density (BMD) values in the femur and the tibia were measured by CT scan. The results of 41 Ca/Ca in longitudinal urinary samples can sensitively reveal the skeletal perturbations caused by bone metastasis of rats, suggests that 41 Ca might be similarly developed for human use and improve clinical management through the assessment of the curative effect and non-invasive detection of the earliest stages of cancer growth in bone.

  12. Prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma

    Science.gov (United States)

    Wang, Wei; Chen, Xiao-Long; Zhao, Shen-Yu; Xu, Yu-Hui; Zhang, Wei-Han; Liu, Kai; Chen, Xin-Zu; Yang, Kun; Zhang, Bo; Chen, Zhi-Xin; Chen, Jia-Ping; Zhou, Zong-Guang; Hu, Jian-Kun

    2016-01-01

    The prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma (GC) has been widely reported and is still under debate. Here, we evaluated the prognostic significance of preoperative serum CA125, CA19-9 and CEA in patients with GC. 1692 patients with GC who underwent gastrectomy were divided into the training (from January 2005 to December 2011, n = 1024) and the validation (from January 2012 to December 2013, n = 668) cohorts. Positive groups of CA125 (> 13.72 U/ml), CA19-9 (> 23.36 U/ml) and CEA (> 4.28 ng/ml) were significantly associated with more advanced clinicopathological traits and worse outcomes than that of negative groups (all P tumor size (P tumor markers (NPTM) were more accurate in prognostic prediction than TNM stage alone. Our findings suggested that elevated preoperative serum CA125, CA19-9 and CEA were associated with more advanced clinicopathological traits and less favorable outcomes. In addition, CA125 as an independent prognostic factor should be further investigated. Nomogram based on NPTM could accurately predict the prognosis of GC patients. PMID:27097114

  13. Study of 40Ca-40Ca elastic scattering at intermediate energy

    International Nuclear Information System (INIS)

    Kumar, Ashok; Srivastava, B.B.

    1980-01-01

    The differential cross sections for 40 Ca- 40 Ca elastic scattering have been calculated at laboratory incident energy of 240 MeV using a sharp cut off of the partial waves below a critical angular momentum, 1sub(c)' to account for absorption. The effective 40 Ca- 40 Ca potential is taken to be the sum of a real nuclear potential and the Coulomb potential. The calculated differential cross sections which are in fair agreement with the experimental data are presented and discussed. (author)

  14. Impact parameter determination for 40Ca + 40Ca reactions using a neural network

    International Nuclear Information System (INIS)

    Haddad, F.; Hagel, K.; Li, J.; Mdeiwayeh, N.; Natowitz, J.B.; Wada, R.; Xiao, B.; David, C.; Freslier, M.; Aichelin, J.

    1995-01-01

    A neural network is used for the impact parameter determination in 40 Ca + 40 Ca reactions at energies between 35 and 70 AMeV. A special attention is devoted to the effect of experimental constraints such as the detection efficiency. An overall improvement of the impact parameter determination of 25% is obtained with the neural network. The neural network technique is then used in the analysis of the Ca+Ca data at 35 AMeV and allows separation of three different class of events among the selected 'complete' events. (authors). 8 refs., 5 figs

  15. Mg/Ca of Continental Ostracode Shells

    Science.gov (United States)

    Ito, E.; Forester, R. M.; Marco-Barba, J.; Mezquita, F.

    2007-12-01

    Marine ionic chemistry is thought to remain constant. This, together with the belief that marine calcifiers partition Mg/Ca in a systematic manner as functions of temperature (and Mg/Ca) of water forms the basis of the Mg/Ca thermometer. In continental settings both of these assumptions are usually not true. Continental waters contain a wide variety of solutes in absolute and relative ion concentrations. Hence, waters with identical Mg/Ca may have very different concentrations of Mg and Ca and very different anions. Here we use two examples to focus on the effects of ion chemistry on Mg/Ca partitioning in continental ostracode shells and we ignore the complexities of solute evolution, which can change Mg/Ca over timescales of minutes to millennia. Palacios-Fest and Dettman (2001) conducted a monthly study of ,Cypridopsis vidua at El Yeso Lake in Sonora, Mexico. They established a relation between temperature and average shell Mg/Ca using regression analyses on averaged data. When their Mg/Ca-temperature relation is applied to monthly ,C. vidua data from Page Pond near Cleveland, Ohio, water temperatures of -8 to -1°C are obtained. The observed Mg/Ca ranges for El Yeso Lake (0.31 to 0.46) and Page Pond (0.33 to 0.46) are similar, as are their specific conductivities (700 to 850μS for El Yeso Lake; 400 to 600μS for Page Pond). However, [Ca] is 140-260 mg/L for El Yeso, but only 70-90 mg/L for Page Pond. Page Pond data, in fact, shows a good temperature shell Mg/Ca relation for .C. vidua, but the relation is different from that at El Yeso. Hence, shell Mg/Ca is a multi-valued, family of curves function of temperature and Mg/Ca of water that depends on the [Mg] and [Ca] values in water and perhaps other factors. Our second example comes from sites near Valencia, Spain and involves shell data for ,Cyprideis torosa, an estuarine ostracode that is tolerant of a wide range of salinity and can live in continental waters as long as the carbonate alkalinity to Ca ratio is

  16. Absolute Ca Isotopic Measurement Using an Improved Double Spike Technique

    Directory of Open Access Journals (Sweden)

    Jason Jiun-San Shen

    2009-01-01

    Full Text Available A new vector analytical method has been developed in order to obtain the true isotopic composition of the 42Ca-48Ca double spike. This is achieved by using two different sample-spike mixtures combined with the double spike and natural Ca data. Be cause the natural sample (two mixtures and the spike should all lie on a single mixing line, we are able to con strain the true isotopic composition of our double spike using this new approach. Once the isotopic composition of the Ca double spike is established, we are able to obtain the true Ca isotopic composition of the NIST Ca standard SRM915a, 40Ca/44Ca = 46.537 ± 2 (2sm, n = 55, 42Ca/44Ca = 0.31031 ± 1, 43Ca/44Ca = 0.06474 ± 1, and 48Ca/44Ca = 0.08956 ± 1. De spite an off set of 1.3% in 40Ca/44Ca between our result and the previously re ported value (Russell et al. 1978, our data indicate an off set of 1.89__in 40Ca/44Ca between SRM915a and seawater, entirely consistent with the published results.

  17. Losing the beat: deficits in temporal coordination

    Science.gov (United States)

    Palmer, Caroline; Lidji, Pascale; Peretz, Isabelle

    2014-01-01

    Tapping or clapping to an auditory beat, an easy task for most individuals, reveals precise temporal synchronization with auditory patterns such as music, even in the presence of temporal fluctuations. Most models of beat-tracking rely on the theoretical concept of pulse: a perceived regular beat generated by an internal oscillation that forms the foundation of entrainment abilities. Although tapping to the beat is a natural sensorimotor activity for most individuals, not everyone can track an auditory beat. Recently, the case of Mathieu was documented (Phillips-Silver et al. 2011 Neuropsychologia 49, 961–969. (doi:10.1016/j.neuropsychologia.2011.02.002)). Mathieu presented himself as having difficulty following a beat and exhibited synchronization failures. We examined beat-tracking in normal control participants, Mathieu, and a second beat-deaf individual, who tapped with an auditory metronome in which unpredictable perturbations were introduced to disrupt entrainment. Both beat-deaf cases exhibited failures in error correction in response to the perturbation task while exhibiting normal spontaneous motor tempi (in the absence of an auditory stimulus), supporting a deficit specific to perception–action coupling. A damped harmonic oscillator model was applied to the temporal adaptation responses; the model's parameters of relaxation time and endogenous frequency accounted for differences between the beat-deaf cases as well as the control group individuals. PMID:25385783

  18. Developmental psychopathology: Attention Deficit Hyperactivity Disorder (ADHD

    Directory of Open Access Journals (Sweden)

    Petermann Franz

    2009-09-01

    Full Text Available Abstract Background Attention Deficit/Hyperactivity Disorder (ADHD, formerly regarded as a typical childhood disorder, is now known as a developmental disorder persisting over the lifespan. Starting in preschool-age, symptoms vary depending on the age group affected. Method According to the variability of ADHD-symptoms and the heterogeneity of comorbid psychiatric disorders, a broad review of recent studies was performed. These findings were summarized in a developmental psychopathological model, documenting relevant facts on a timeline. Results Based on a genetic disposition and a neuropsychological deregulation, there is evidence for factors which persist across the lifespan, change age-dependently, or show validity in a specific developmental phase. Qualitative changes can be found for children in preschool-age and adults. Conclusion These differences have implications for clinical practice as they can be used for prevention, diagnostic proceedings, and therapeutic intervention as well as for planning future studies. The present article is a translated and modified version of the German article "Entwicklungspsychopathologie der ADHS", published in Zeitschrift für Psychiatrie, Psychologie und Psychotherapie, 56, 2008, S. 265-274.

  19. ATTENTION DEFICIT HYPERACTIVITY DISORDER. A CLINICAL LECTURE

    Directory of Open Access Journals (Sweden)

    A. S. Kotov

    2015-01-01

    Full Text Available Attention deficit hyperactivity disorder (ADHD is a serious problem to pediatric neurologists. The prevalence of ADHD in developed countries ranges from 1 to 20 %. ADHD is characterized by a triad of symptoms: inattention, hyperactivity, and impulsivity (the International Statistical Classification of Diseases, 10th revision, codes it as F90 and it is the most common conduct disorder in children. The etiology of ADHD remains disсutable to the present day; there are a few basic concepts of the origin of this disorder. Its manifestations may be a reason for family conflicts, poor peer relationships, social and school maladjustment, learning problems, lower academic performance, accidents and injuries, smoking, psychoactive substance abuse (toxicomania, narcomania, delinquencies, deviant social behavior, thus having a negative impact on all spheres of a patient’s life. The manifestations of ADHD may continue in adulthood, resulting in work and family life problems, low self-evaluation, alcohol and psychoactive substance abuse, and other unfavorable consequences. The authors describe the etiology, pathogenesis, diagnostic principles (diagnostic scales and tests, differential diagnosis (by setting out a large group of different diseases, the manifestations of which can mimic ADHD, treatment, and prognosis of the disorder. Within its therapeutic correction framework, the authors present the definition and general principles of Montessori therapy, including recommendations for parents and relatives to deal with children with ADHD. 

  20. Developmental psychopathology: Attention Deficit Hyperactivity Disorder (ADHD).

    Science.gov (United States)

    Schmidt, Sören; Petermann, Franz

    2009-09-17

    Attention Deficit/Hyperactivity Disorder (ADHD), formerly regarded as a typical childhood disorder, is now known as a developmental disorder persisting over the lifespan. Starting in preschool-age, symptoms vary depending on the age group affected. According to the variability of ADHD-symptoms and the heterogeneity of comorbid psychiatric disorders, a broad review of recent studies was performed. These findings were summarized in a developmental psychopathological model, documenting relevant facts on a timeline. Based on a genetic disposition and a neuropsychological deregulation, there is evidence for factors which persist across the lifespan, change age-dependently, or show validity in a specific developmental phase. Qualitative changes can be found for children in preschool-age and adults. These differences have implications for clinical practice as they can be used for prevention, diagnostic proceedings, and therapeutic intervention as well as for planning future studies. The present article is a translated and modified version of the German article "Entwicklungspsychopathologie der ADHS", published in Zeitschrift für Psychiatrie, Psychologie und Psychotherapie, 56, 2008, S. 265-274.