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Sample records for delta theta alpha

  1. Clozapine augments delta, theta, and right frontal EEG alpha power in schizophrenic patients.

    Science.gov (United States)

    Maccrimmon, D; Brunet, D; Criollo, M; Galin, H; Lawson, J S

    2012-01-01

    Objective. To explore the Quantitative EEG (QEEG) effects of established clozapine therapy regimes compared to those of previous ineffective antipsychotic regimes among 64 chronic (DSM-IV) schizophrenic patients. Methods. Data from 20 EEG channels referenced to linked ears were collected before and during maintenance clozapine therapy (mean duration 1.4 years). Absolute power was calculated in six frequency bands: delta (0.4-3.6 Hz), theta (4.2-7.8 Hz), alpha (8.2-11.8 Hz), beta1 (12.2-15.8 Hz), beta2 (16.2-19.8 Hz), and beta3 (20.2-23.8 Hz). Results. Clozapine augments power globally in the delta and theta bands, but this effect is more pronounced over frontal areas. Beta3 power was reduced. Alpha showed a frontal increase, more pronounced in the right, coupled with a posterior decrease with no net change in overall power. Conclusion. The demonstration of a significant clozapine-induced alpha topographic shift frontally and to the right is a novel discovery that may serve to encourage further investigations of subcortical structures in attempts to better understand the diverse aetiologies and optimal treatments of the schizophrenias.

  2. Event-related delta, theta, alpha and gamma correlates to auditory oddball processing during Vipassana meditation

    Science.gov (United States)

    Delorme, Arnaud; Polich, John

    2013-01-01

    Long-term Vipassana meditators sat in meditation vs. a control (instructed mind wandering) states for 25 min, electroencephalography (EEG) was recorded and condition order counterbalanced. For the last 4 min, a three-stimulus auditory oddball series was presented during both meditation and control periods through headphones and no task imposed. Time-frequency analysis demonstrated that meditation relative to the control condition evinced decreased evoked delta (2–4 Hz) power to distracter stimuli concomitantly with a greater event-related reduction of late (500–900 ms) alpha-1 (8–10 Hz) activity, which indexed altered dynamics of attentional engagement to distracters. Additionally, standard stimuli were associated with increased early event-related alpha phase synchrony (inter-trial coherence) and evoked theta (4–8 Hz) phase synchrony, suggesting enhanced processing of the habituated standard background stimuli. Finally, during meditation, there was a greater differential early-evoked gamma power to the different stimulus classes. Correlation analysis indicated that this effect stemmed from a meditation state-related increase in early distracter-evoked gamma power and phase synchrony specific to longer-term expert practitioners. The findings suggest that Vipassana meditation evokes a brain state of enhanced perceptual clarity and decreased automated reactivity. PMID:22648958

  3. Alpha Theta Meditation: Phenomenological, neurophysiologic ...

    African Journals Online (AJOL)

    African Journal for Physical Activity and Health Sciences ... neurophysiologic, mindfulness, mood, health and sport implications ... Integrated findings are in line with other studies which support the psychological value of alpha theta training.

  4. Delta, theta, and alpha event-related oscillations in alcoholics during Go/NoGo task: Neurocognitive deficits in execution, inhibition, and attention processing.

    Science.gov (United States)

    Pandey, Ashwini K; Kamarajan, Chella; Manz, Niklas; Chorlian, David B; Stimus, Arthur; Porjesz, Bernice

    2016-02-01

    Higher impulsivity observed in alcoholics is thought to be due to neurocognitive functional deficits involving impaired inhibition in several brain regions and/or neuronal circuits. Event-related oscillations (EROs) offer time-frequency measure of brain rhythms during perceptual and cognitive processing, which provide a detailed view of neuroelectric oscillatory responses to external/internal events. The present study examines evoked power (temporally locked to events) of oscillatory brain signals in alcoholics during an equal probability Go/NoGo task, assessing their functional relevance in execution and inhibition of a motor response. The current study hypothesized that increases in the power of slow frequency bands and their topographical distribution is associated with tasks that have increased cognitive demands, such as the execution and inhibition of a motor response. Therefore, it is hypothesized that alcoholics would show lower spectral power in their topographical densities compared to controls. The sample consisted of 20 right-handed abstinent alcoholic males and 20 age and gender-matched healthy controls. Evoked delta (1.0-3.5Hz; 200-600ms), theta (4.0-7.5Hz; 200-400ms), slow alpha (8.0-9.5Hz; 200-300ms), and fast alpha (10.0-12.5Hz; 100-200ms) ERO power were compared across group and task conditions. Compared to controls, alcoholics had higher impulsiveness scores on the Barrett Impulsiveness Scale (BIS-11) and made more errors on Go trials. Alcoholics showed significantly lower evoked delta, theta, and slow alpha power compared to controls for both Go and NoGo task conditions, and lower evoked fast alpha power compared to controls for only the NoGo condition. The results confirm previous findings and are suggestive of neurocognitive deficits while executing and suppressing a motor response. Based on findings in the alpha frequency ranges, it is further suggested that the inhibitory processing impairments in alcoholics may arise from inadequate early

  5. Dynamical stability of the alpha and theta phases of alumina

    DEFF Research Database (Denmark)

    Lodziana, Zbigniew; Parlinski, K.

    2003-01-01

    Using density functional calculations the phonon dispersion relations, phonon density of states, and free energy of theta and alpha phases of alumina are investigated. The temperature dependence of the free energy indicates that entropy contributes to the destabilization of the alpha phase...

  6. Expectancy Effects in Feedback Processing are Explained Primarily by Time-frequency Delta not Theta.

    Science.gov (United States)

    Watt, Adreanna T M; Bachman, Matthew D; Bernat, Edward M

    2017-08-30

    The roles of outcome valence and expectancy in feedback processing have been investigated as important factors modulating event-related potential (ERP) measures including the feedback negativity (FN) and P300, but results have been inconsistent. Recent work from our group has shown that processes underlying the FN and P300 are better represented as separable processes in the theta (3-7Hz) and delta (0-3Hz) ranges using time-frequency analysis. The current study evaluated the modulation of time-domain FN and P300 and time-frequency theta and delta to outcome valence and expectancy in a gambling feedback task paradigm.Results revealed that the FN was sensitive to valence but not expectancy, and that valence effects were driven by loss-sensitive theta and gain-sensitive delta. Alternatively, the P300 was sensitive to the expectedness of outcomes but only for gain trials, and these expectancy differences were explained by time-frequency delta not theta. These results add to a growing body of research showing that time-frequency measures reflect separable processes underlying time-domain components, where theta is more sensitive to primary task features and less sensitive to secondary features while delta is sensitive to primary and more complex, secondary task features. Copyright © 2017. Published by Elsevier B.V.

  7. Corticostriatal field potentials are modulated at delta and theta frequencies during interval-timing task in rodents

    Directory of Open Access Journals (Sweden)

    Eric B Emmons

    2016-04-01

    Full Text Available Organizing movements in time is a critical and highly conserved feature of mammalian behavior. Temporal control of action requires corticostriatal networks. We investigate these networks in rodents using a two-interval timing task while recording local field potentials in medial frontal cortex or dorsomedial striatum. Consistent with prior work, we found cue-triggered delta (1-4 Hz and theta activity (4-8 Hz primarily in rodent medial frontal cortex. We observed delta activity across temporal intervals in medial frontal cortex and dorsomedial striatum. Rewarded responses were associated with increased delta activity in medial frontal cortex. Activity in theta bands in medial frontal cortex and delta bands in the striatum was linked with the timing of responses. These data suggest both delta and theta activity in frontostriatal networks are modulated during interval timing and that activity in these bands may be involved in the temporal control of action.

  8. Corrections to Scaling Neutrino Mixing: Non-zero $\\theta_{13}, \\delta_{CP}$ and Baryon Asymmetry

    CERN Document Server

    Kalita, Rupam; Das, Mrinal Kumar

    2014-01-01

    We study a very specific type of neutrino mass and mixing structure based on the idea of Strong Scaling Ansatz (SSA) where the ratios of neutrino mass matrix elements belonging to two different columns are equal. There are three such possibilities, all of which are disfavored by the latest neutrino oscillation data. We focus on the specific scenario which predicts vanishing reactor mixing angle $\\theta_{13}$ and inverted hierarchy with vanishing lightest neutrino mass. Motivated by several recent attempts to explain non-zero $\\theta_{13}$ by incorporating corrections to a leading order neutrino mass or mixing matrix giving $\\theta_{13}=0$, here we study the origin of non-zero $\\theta_{13}$ as well as leptonic Dirac CP phase $\\delta_{CP}$ by incorporating two different corrections to scaling neutrino mass and mixing: one where type II seesaw acts as a correction to scaling neutrino mass matrix and the other with charged lepton correction to scaling neutrino mixing. Although scaling neutrino mass matrix origina...

  9. Type II Seesaw Origin of Non-zero $\\theta_{13}, \\delta_{CP} $ and Leptogenesis

    CERN Document Server

    Borah, Debasish

    2014-01-01

    We discuss the possible origin of non-zero reactor mixing angle $\\theta_{13}$ and Dirac CP phase $\\delta_{CP}$ in the leptonic sector from a combination of type I and type II seesaw mechanisms. Type I seesaw contribution to neutrino mass matrix is of tri-bimaximal (TBM) type which gives rise to vanishing $\\theta_{13}$ leaving the Dirac CP phase undetermined. If the Dirac neutrino mass matrix is assumed to take the diagonal charged lepton type structure, such a TBM type neutrino mass matrix originating from type I seesaw corresponds to real values of Dirac Yukawa couplings in the terms $Y_{ij} \\bar{L_i} H N_j$. This makes the process of right handed heavy neutrino decay into a light neutrino and Higgs $(N \\rightarrow \

  10. Stimulus sequence context differentially modulates inhibition-related theta and delta band activity in a go/no-go task.

    Science.gov (United States)

    Harper, Jeremy; Malone, Stephen M; Bachman, Matthew D; Bernat, Edward M

    2016-05-01

    Recent work suggests that dissociable activity in theta and delta frequency bands underlies several common ERP components, including the no-go N2/P3 complex, which can better index separable functional processes than traditional time-domain measures. Reports have also demonstrated that neural activity can be affected by stimulus sequence context information (i.e., the number and type of preceding stimuli). Stemming from prior work demonstrating that theta and delta index separable processes during response inhibition, the current study assessed sequence context in a go/no-go paradigm in which the number of go stimuli preceding each no-go was selectively manipulated. Principal component analysis of time-frequency representations revealed differential modulation of evoked theta and delta related to sequence context, where delta increased robustly with additional preceding go stimuli, while theta did not. Findings are consistent with the view that theta indexes simpler initial salience-related processes, while delta indexes more varied and complex processes related to a variety of task parameters. © 2016 Society for Psychophysiological Research.

  11. Working memory performance inversely predicts spontaneous delta and theta-band scaling relations.

    Science.gov (United States)

    Euler, Matthew J; Wiltshire, Travis J; Niermeyer, Madison A; Butner, Jonathan E

    2016-04-15

    Electrophysiological studies have strongly implicated theta-band activity in human working memory processes. Concurrently, work on spontaneous, non-task-related oscillations has revealed the presence of long-range temporal correlations (LRTCs) within sub-bands of the ongoing EEG, and has begun to demonstrate their functional significance. However, few studies have yet assessed the relation of LRTCs (also called scaling relations) to individual differences in cognitive abilities. The present study addressed the intersection of these two literatures by investigating the relation of narrow-band EEG scaling relations to individual differences in working memory ability, with a particular focus on the theta band. Fifty-four healthy adults completed standardized assessments of working memory and separate recordings of their spontaneous, non-task-related EEG. Scaling relations were quantified in each of the five classical EEG frequency bands via the estimation of the Hurst exponent obtained from detrended fluctuation analysis. A multilevel modeling framework was used to characterize the relation of working memory performance to scaling relations as a function of general scalp location in Cartesian space. Overall, results indicated an inverse relationship between both delta and theta scaling relations and working memory ability, which was most prominent at posterior sensors, and was independent of either spatial or individual variability in band-specific power. These findings add to the growing literature demonstrating the relevance of neural LRTCs for understanding brain functioning, and support a construct- and state-dependent view of their functional implications.

  12. Theta-alpha EEG phase distributions in the frontal area for dissociation of visual and auditory working memory

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    Akiyama, Masakazu; Tero, Atsushi; Kawasaki, Masahiro; Nishiura, Yasumasa; Yamaguchi, Yoko

    2017-01-01

    Working memory (WM) is known to be associated with synchronization of the theta and alpha bands observed in electroencephalograms (EEGs). Although frontal-posterior global theta synchronization appears in modality-specific WM, local theta synchronization in frontal regions has been found in modality-independent WM. How frontal theta oscillations separately synchronize with task-relevant sensory brain areas remains an open question. Here, we focused on theta-alpha phase relationships in frontal areas using EEG, and then verified their functional roles with mathematical models. EEG data showed that the relationship between theta (6 Hz) and alpha (12 Hz) phases in the frontal areas was about 1:2 during both auditory and visual WM, and that the phase distributions between auditory and visual WM were different. Next, we used the differences in phase distributions to construct FitzHugh-Nagumo type mathematical models. The results replicated the modality-specific branching by orthogonally of the trigonometric functions for theta and alpha oscillations. Furthermore, mathematical and experimental results were consistent with regards to the phase relationships and amplitudes observed in frontal and sensory areas. These results indicate the important role that different phase distributions of theta and alpha oscillations have in modality-specific dissociation in the brain. PMID:28266595

  13. Deqi Induction by HT7 Acupuncture Alters Theta and Alpha Band Coherence in Human Healthy Subjects.

    Science.gov (United States)

    Lee, Go-Eun; Yun, Jong-Min; Yang, Seung-Bum; Kang, Yeonseok; Kang, Hyung-Won; Choi, Kwang-Ho; Kim, Junbeom; Kwon, O Sang; Park, Ji-Eun; Kim, Jae-Hyo

    2017-01-01

    The aim of this preliminary study is to investigate the changes in phase synchronization in the theta and alpha bands before and during the performance of classical acupuncture on the Sinmun (HT7). The electroencephalogram (EEG) signals from nine healthy young subjects were recorded before and during acupuncture in the "closed-eye" state. The EEG signals were acquired from 19 surface scalp electrodes (FP1, FP2, F7, F3, Fz F4, F8, T3, C3, Cz, C4, T4, T5, P3, Pz, P4, T6, O1, and O2). Needles were inserted into the HT7 bilaterally and were then manipulated to induce deqi and retained for 15 minutes. Phase synchronization was measured by phase coherence. In the theta band, coherence significantly increased between the temporal (T5, T6) and occipital areas (O1, O2) during the acupuncture stimulation. In the alpha band, coherence significantly increased between the left temporal area (T5) and other areas (frontal, parietal, and occipital). Phase coherence in the theta and alpha bands tended to increase during the retention of the acupuncture needles after deqi. Therefore, it can be concluded that acupuncture stimulation with deqi is clinically effective via the central nervous system (CNS).

  14. Deqi Induction by HT7 Acupuncture Alters Theta and Alpha Band Coherence in Human Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Go-Eun Lee

    2017-01-01

    Full Text Available The aim of this preliminary study is to investigate the changes in phase synchronization in the theta and alpha bands before and during the performance of classical acupuncture on the Sinmun (HT7. The electroencephalogram (EEG signals from nine healthy young subjects were recorded before and during acupuncture in the “closed-eye” state. The EEG signals were acquired from 19 surface scalp electrodes (FP1, FP2, F7, F3, Fz F4, F8, T3, C3, Cz, C4, T4, T5, P3, Pz, P4, T6, O1, and O2. Needles were inserted into the HT7 bilaterally and were then manipulated to induce deqi and retained for 15 minutes. Phase synchronization was measured by phase coherence. In the theta band, coherence significantly increased between the temporal (T5, T6 and occipital areas (O1, O2 during the acupuncture stimulation. In the alpha band, coherence significantly increased between the left temporal area (T5 and other areas (frontal, parietal, and occipital. Phase coherence in the theta and alpha bands tended to increase during the retention of the acupuncture needles after deqi. Therefore, it can be concluded that acupuncture stimulation with deqi is clinically effective via the central nervous system (CNS.

  15. Theta, alpha and beta burst transcranial magnetic stimulation: brain modulation in tinnitus

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    Dirk De Ridder, Elsa van der Loo, Karolien Van der Kelen, Tomas Menovsky, Paul van de Heyning, Aage Moller

    2007-01-01

    Full Text Available Introduction: Some forms of tinnitus are considered to be auditory phantom phenomena related to reorganization and hyperactivity of the auditory central nervous system. Repetitive transcranial magnetic stimulation (rTMS is a non-invasive tool capable of modulating human brain activity, using single pulse or burst stimuli. Burst rTMS has only been performed in the theta range, and has not been used clinically. The authors analyze whether burst TMS at theta (5 Hz, alpha (10 Hz and beta (20 Hz frequencies can temporarily suppress narrow band noise/white noise tinnitus, which has been demonstrated to be intractable to tonic stimulation. Methods: rTMS is performed both in tonic and burst mode in 46 patients contralateral to the tinnitus side, at 5, 10 and 20 Hz. Fourteen placebo negative rTMS responders are further analyzed. Results: In 5 patients, maximal tinnitus suppression is obtained with theta, in 2 with alpha and in 7 with beta burst stimulation. Burst rTMS suppresses narrow band/white tinnitus much better than tonic rTMS t(13=6.4, p<.000. Women experience greater suppression of their tinnitus with burst stimulation than men, t(12=2.9, p<.05. Furthermore left sided tinnitus is perceived as more distressing on the TQ than right sided tinnitus, t(12=3.2, p<.01. The lower the tinnitus pitch the more effectively rTMS suppresses tinnitus(r=-0.65, p<0.05. Discussion: Burst rTMS can be used clinically, not only theta burst, but also alpha and beta burst. Burst rTMS is capable of suppressing narrow band/white noise tinnitus very much better than tonic rTMS. This could be due the simple fact that burst neuromodulation is more powerful than tonic neuromodulation or to a differential effect of burst and tonic stimulation on the lemniscal and extralemniscal auditory system. In some patients only alpha or beta burst rTMS is capable of suppressing tinnitus, and theta burst not. Therefore in future rTMS studies it could be worthwhile not to limit burst

  16. Heat Kernel Estimate for $\\Delta+\\Delta^{\\alpha/2}$ in $C^{1,1}$ open sets

    CERN Document Server

    Chen, Zhen-Qing; Song, Renming

    2010-01-01

    We consider a family of pseudo differential operators $\\{\\Delta+ a^\\alpha \\Delta^{\\alpha/2}; a\\in (0, 1]\\}$ on $\\bR^d$ for every $d\\geq 1$ that evolves continuously from $\\Delta$ to $\\Delta + \\Delta^{\\alpha/2}$, where $\\alpha \\in (0, 2)$. It gives rise to a family of L\\'evy processes $\\{X^a, a\\in (0, 1]\\}$ in $\\bR^d$, where $X^a$ is the sum of a Brownian motion and an independent symmetric $\\alpha$-stable process with weight $a$. We establish sharp two-sided estimates for the heat kernel of $\\Delta + a^{\\alpha} \\Delta^{\\alpha/2}$ with zero exterior condition in a family of open subsets, including bounded $C^{1, 1}$ (possibly disconnected) open sets. This heat kernel is also the transition density of the sum of a Brownian motion and an independent symmetric $\\alpha$-stable process with weight $a$ in such open sets. Our result is the first sharp two-sided estimates for the transition density of a Markov process with both diffusion and jump components in open sets. Moreover, our result is uniform in $a$ in the s...

  17. Acoustic landmarks drive delta-theta oscillations to enable speech comprehension by facilitating perceptual parsing.

    Science.gov (United States)

    Doelling, Keith B; Arnal, Luc H; Ghitza, Oded; Poeppel, David

    2014-01-15

    A growing body of research suggests that intrinsic neuronal slow (speech and other spectro-temporally complex auditory signals. Within this framework, several recent studies have identified critical-band temporal envelopes as the specific acoustic feature being reflected by the phase of these oscillations. However, how this alignment between speech acoustics and neural oscillations might underpin intelligibility is unclear. Here we test the hypothesis that the 'sharpness' of temporal fluctuations in the critical band envelope acts as a temporal cue to speech syllabic rate, driving delta-theta rhythms to track the stimulus and facilitate intelligibility. We interpret our findings as evidence that sharp events in the stimulus cause cortical rhythms to re-align and parse the stimulus into syllable-sized chunks for further decoding. Using magnetoencephalographic recordings, we show that by removing temporal fluctuations that occur at the syllabic rate, envelope-tracking activity is reduced. By artificially reinstating these temporal fluctuations, envelope-tracking activity is regained. These changes in tracking correlate with intelligibility of the stimulus. Together, the results suggest that the sharpness of fluctuations in the stimulus, as reflected in the cochlear output, drive oscillatory activity to track and entrain to the stimulus, at its syllabic rate. This process likely facilitates parsing of the stimulus into meaningful chunks appropriate for subsequent decoding, enhancing perception and intelligibility. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Differentiation of Boc-protected alpha,delta-/delta,alpha- and beta,delta-/delta,beta-hybrid peptide positional isomers by electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Raju, G; Ramesh, V; Srinivas, R; Sharma, G V M; Shoban Babu, B

    2010-06-01

    Two new series of Boc-N-alpha,delta-/delta,alpha- and beta,delta-/delta,beta-hybrid peptides containing repeats of L-Ala-delta(5)-Caa/delta(5)-Caa-L-Ala and beta(3)-Caa-delta(5)-Caa/delta(5)-Caa-beta(3)-Caa (L-Ala = L-alanine, Caa = C-linked carbo amino acid derived from D-xylose) have been differentiated by both positive and negative ion electrospray ionization (ESI) ion trap tandem mass spectrometry (MS/MS). MS(n) spectra of protonated isomeric peptides produce characteristic fragmentation involving the peptide backbone, the Boc-group, and the side chain. The dipeptide positional isomers are differentiated by the collision-induced dissociation (CID) of the protonated peptides. The loss of 2-methylprop-1-ene is more pronounced for Boc-NH-L-Ala-delta-Caa-OCH(3) (1), whereas it is totally absent for its positional isomer Boc-NH-delta-Caa-L-Ala-OCH(3) (7), instead it shows significant loss of t-butanol. On the other hand, second isomeric pair shows significant loss of t-butanol and loss of acetone for Boc-NH-delta-Caa-beta-Caa-OCH(3) (18), whereas these are insignificant for its positional isomer Boc-NH-beta-Caa-delta-Caa-OCH(3) (13). The tetra- and hexapeptide positional isomers also show significant differences in MS(2) and MS(3) CID spectra. It is observed that 'b' ions are abundant when oxazolone structures are formed through five-membered cyclic transition state and cyclization process for larger 'b' ions led to its insignificant abundance. However, b(1)(+) ion is formed in case of delta,alpha-dipeptide that may have a six-membered substituted piperidone ion structure. Furthermore, ESI negative ion MS/MS has also been found to be useful for differentiating these isomeric peptide acids. Thus, the results of MS/MS of pairs of di-, tetra-, and hexapeptide positional isomers provide peptide sequencing information and distinguish the positional isomers.

  19. Phase synchronization of delta and theta oscillations increase during the detection of relevant lexical information

    Directory of Open Access Journals (Sweden)

    Enzo eBrunetti

    2013-06-01

    Full Text Available During monitoring of the discourse, the detection of the relevance of incoming lexical information could be critical for its incorporation to update mental representations in memory. Because, in these situations, the relevance for lexical information is defined by abstract rules that are maintained in memory, results critical to understand how an abstract level of knowledge maintained in mind mediates the detection of the lower-level semantic information. In the present study, we propose that neuronal oscillations participate in the detection of relevant lexical information, based on ‘kept in mind’ rules deriving from more abstract semantic information. We tested our hypothesis using an experimental paradigm that restricted the detection of relevance to inferences based on explicit information, thus controlling for ambiguities derived from implicit aspects. We used a categorization task, in which the semantic relevance was previously defined based on the congruency between a kept in mind category (abstract knowledge, and the lexical-semantic information presented. Our results show that during the detection of the relevant lexical information, phase synchronization of neuronal oscillations selectively increases in delta and theta frequency bands during the interval of semantic analysis. These increments were independent of the semantic category maintained in memory, had a temporal profile specific for each subject, and were mainly induced, as they had no effect on the evoked mean global field power. Also, recruitment of an increased number of pairs of electrodes was a robust observation during the detection of semantic contingent words. These results are consistent with the notion that the detection of relevant lexical information based on a particular semantic rule, could be mediated by increasing the global phase synchronization of neuronal oscillations, which may contribute to the recruitment of an extended number of cortical regions.

  20. Recalling and forgetting dreams: theta and alpha oscillations during sleep predict subsequent dream recall.

    Science.gov (United States)

    Marzano, Cristina; Ferrara, Michele; Mauro, Federica; Moroni, Fabio; Gorgoni, Maurizio; Tempesta, Daniela; Cipolli, Carlo; De Gennaro, Luigi

    2011-05-04

    Under the assumption that dream recall is a peculiar form of declarative memory, we have hypothesized that (1) the encoding of dream contents during sleep should share some electrophysiological mechanisms with the encoding of episodic memories of the awake brain and (2) recalling a dream(s) after awakening from non-rapid eye movement (NREM) and rapid eye movement (REM) sleep should be associated with different brain oscillations. Here, we report that cortical brain oscillations of human sleep are predictive of successful dream recall. In particular, after morning awakening from REM sleep, a higher frontal 5-7 Hz (theta) activity was associated with successful dream recall. This finding mirrors the increase in frontal theta activity during successful encoding of episodic memories in wakefulness. Moreover, in keeping with the different EEG background, a different predictive relationship was found after awakening from stage 2 NREM sleep. Specifically, a lower 8-12 Hz (alpha) oscillatory activity of the right temporal area was associated with a successful dream recall. These findings provide the first evidence of univocal cortical electroencephalographic correlates of dream recall, suggesting that the neurophysiological mechanisms underlying the encoding and recall of episodic memories may remain the same across different states of consciousness.

  1. High theta and low alpha powers may be indicative of BCI-illiteracy in motor imagery.

    Directory of Open Access Journals (Sweden)

    Minkyu Ahn

    Full Text Available In most brain computer interface (BCI systems, some target users have significant difficulty in using BCI systems. Such target users are called 'BCI-illiterate'. This phenomenon has been poorly investigated, and a clear understanding of the BCI-illiteracy mechanism or a solution to this problem has not been reported to date. In this study, we sought to demonstrate the neurophysiological differences between two groups (literate, illiterate with a total of 52 subjects. We investigated recordings under non-task related state (NTS which is collected during subject is relaxed with eyes open. We found that high theta and low alpha waves were noticeable in the BCI-illiterate relative to the BCI-literate people. Furthermore, these high theta and low alpha wave patterns were preserved across different mental states, such as NTS, resting before motor imagery (MI, and MI states, even though the spatial distribution of both BCI-illiterate and BCI-literate groups did not differ. From these findings, an effective strategy for pre-screening subjects for BCI illiteracy has been determined, and a performance factor that reflects potential user performance has been proposed using a simple combination of band powers. Our proposed performance factor gave an r = 0.59 (r(2 = 0.34 in a correlation analysis with BCI performance and yielded as much as r = 0.70 (r(2 = 0.50 when seven outliers were rejected during the evaluation of whole data (N = 61, including BCI competition datasets (N = 9. These findings may be directly applicable to online BCI systems.

  2. Effect of alpha-cypermethrin and theta-cypermethrin on delayed rectifier potassium currents in rat hippocampal neurons.

    Science.gov (United States)

    Tian, Yu-Tao; Liu, Zhao-Wei; Yao, Yang; Yang, Zhuo; Zhang, Tao

    2009-03-01

    Cypermethrin is a photostable synthetic pyrethroid and the most widely used Type II pyrethroid pesticide. The effects of two different stereoisomers of cypermethrin insecticides, alpha-cypermethrin and theta-cypermethrin, on the delayed rectifier potassium current (IK) in hippocampal neurons of rat, were studied using whole-cell patch clamp technique. Alpha-cypermethrin and theta-cypermethrin decreased the amplitude value of IK, and shifted the steady state activation curve of IK towards negative potential at any concentrations (10(-9) M, 10(-8) M, 10(-7) M). Furthermore, at higher concentration, alpha-cypermethrin (10(-7) M) and theta-cypermethrin (10(-8) M, 10(-7) M) had observable effects of the steady state inactivation of IK. The results suggest that IK is the target of alpha-cypermethrin and theta-cypermethrin, which may explain the mechanism of toxic effects of both steroeisomers of cypermethrin on mammalian neurons. Cypermethrin-altered properties of voltage gated delayed rectifier K+ channels may contribute to neurotoxicity by eliciting abnormal electrical discharges in hippocampal CA3 neurons.

  3. Alpha- and theta-range cortical synchronization and corticomuscular coherence during joystick manipulation in a virtual navigation task.

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    Hori, Satoshi; Matsumoto, Jumpei; Hori, Etsuro; Kuwayama, Naoya; Ono, Taketoshi; Kuroda, Satoshi; Nishijo, Hisao

    2013-10-01

    Previous studies have reported that multiple brain regions are activated during spatial navigation, but it remains unclear how this activation is converted to motor commands for navigation. This study was aimed to investigate synchronization across different brain regions and between cortical areas and muscles during spatial navigation. This synchronization has been suggested to be essential for integrating activity in the multiple brain areas to support higher cognitive functions and for conversion of cortical activity to motor commands. In the present study, the subjects were required to sequentially trace ten checkpoints in a virtual town by manipulating a joystick and to perform this three times while electroencephalograms and electromyograms from the right arm were monitored. Time spent on the task in the third trial was significantly lesser than that in the first trial indicating an improvement in task performance. This repeated learning was associated with an increase in alpha power at the electrodes over the contralateral sensorimotor region and in theta power at the electrodes over the bilateral premotor and frontotemporal regions. Alpha- and theta-range corticocortical coherences between these regions and other brain areas were also increased in the third trial compared to the first trial. Furthermore, alpha- and theta-range corticomuscular coherence was significantly increased in the second and third trials compared to the first trial. These results suggest that alpha- and theta-range synchronous activity across multiple systems is essential for the integrated brain activity required in spatial navigation and for the conversion of this activity to motor commands.

  4. Functional role of delta and theta band oscillations for auditory feedback processing during vocal pitch motor control.

    Science.gov (United States)

    Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Robin, Donald A; Larson, Charles R

    2015-01-01

    The answer to the question of how the brain incorporates sensory feedback and links it with motor function to achieve goal-directed movement during vocalization remains unclear. We investigated the mechanisms of voice pitch motor control by examining the spectro-temporal dynamics of EEG signals when non-musicians (NM), relative pitch (RP), and absolute pitch (AP) musicians maintained vocalizations of a vowel sound and received randomized ± 100 cents pitch-shift stimuli in their auditory feedback. We identified a phase-synchronized (evoked) fronto-central activation within the theta band (5-8 Hz) that temporally overlapped with compensatory vocal responses to pitch-shifted auditory feedback and was significantly stronger in RP and AP musicians compared with non-musicians. A second component involved a non-phase-synchronized (induced) frontal activation within the delta band (1-4 Hz) that emerged at approximately 1 s after the stimulus onset. The delta activation was significantly stronger in the NM compared with RP and AP groups and correlated with the pitch rebound error (PRE), indicating the degree to which subjects failed to re-adjust their voice pitch to baseline after the stimulus offset. We propose that the evoked theta is a neurophysiological marker of enhanced pitch processing in musicians and reflects mechanisms by which humans incorporate auditory feedback to control their voice pitch. We also suggest that the delta activation reflects adaptive neural processes by which vocal production errors are monitored and used to update the state of sensory-motor networks for driving subsequent vocal behaviors. This notion is corroborated by our findings showing that larger PREs were associated with greater delta band activity in the NM compared with RP and AP groups. These findings provide new insights into the neural mechanisms of auditory feedback processing for vocal pitch motor control.

  5. Functional role of delta and theta band oscillations for auditory feedback processing during vocal pitch motor control

    Directory of Open Access Journals (Sweden)

    Roozbeh eBehroozmand

    2015-03-01

    Full Text Available The answer to the question of how the brain incorporates sensory feedback and links it with motor function to achieve goal-directed movement during vocalization remains unclear. We investigated the mechanisms of voice pitch motor control by examining the spectro-temporal dynamics of EEG signals when non-musicians (NM, relative pitch (RP and absolute pitch (AP musicians maintained vocalizations of a vowel sound and received randomized ±100 cents pitch-shift stimuli in their auditory feedback. We identified a phase-synchronized (evoked fronto-central activation within the theta band (5-8 Hz that temporally overlapped with compensatory vocal responses to pitch-shifted auditory feedback and was significantly stronger in RP and AP musicians compared with non-musicians. A second component involved a non-phase-synchronized (induced frontal activation within the delta band (1-4 Hz that emerged at approximately 1 second after the stimulus onset. The delta activation was significantly stronger in the NM compared with RP and AP groups and correlated with the pitch rebound error (PRE, indicating the degree to which subjects failed to re-adjust their voice pitch to baseline after the stimulus offset. We propose that the evoked theta is a neurophysiological marker of enhanced pitch processing in musicians and reflects mechanisms by which humans incorporate auditory feedback to control their voice pitch. We also suggest that the delta activation reflects adaptive neural processes by which vocal production errors are monitored and used to update the state of sensory-motor networks for driving subsequent vocal behaviors. This notion is corroborated by our findings showing that larger PREs were associated with greater delta band activity in the NM compared with RP and AP groups. These findings provide new insights into the neural mechanisms of auditory feedback processing for vocal pitch motor control.

  6. Effects of Increase in Amplitude of Occipital Alpha & Theta Brain Waves on Global Functioning Level of Patients with GAD.

    Science.gov (United States)

    Dadashi, Mohsen; Birashk, Behrooz; Taremian, Farhad; Asgarnejad, Ali Asghar; Momtazi, Saeed

    2015-01-01

    The basic objective of this study is to investigate the effects of alpha and theta brain waves amplitude increase in occipital area on reducing the severity of symptoms of generalized anxiety disorder and to increase the global functioning level in patients with GAD. This study is a quasi-experimental study with pre-test and post-test with two groups. For this purpose, 28 patients who had been referred to Sohrawardi psychiatric and clinical psychology center in Zanjan were studied based on the interview with the psychiatrist, clinical psychologist and using clinical diagnostic criteria for the Diagnostic and Statistical Manual of Mental Disorders text revision - the DSM-IV-TR Fourth Edition diagnosis of GAD, 14 subjects were studied in neurofeedback treatment group and 14 subjects in the waiting list group. Patients in both groups were evaluated at pre-test and post-test with General Anxiety Disorder Scale (GAD-7) and Global Assessment Functioning Scale (GAFs). The treatment group received fifteen 30-minute alpha training sessions and fifteen 30-minute theta brain training sessions in occipital area by neurofeedback training (treatment group). This evaluation was performed according to the treatment protocol to increase the alpha and theta waves. And no intervention was done in the waiting list group. But due to ethical issues after the completion of the study all the subjects in the waiting list group were treated. The results showed that increase of alpha and theta brain waves amplitude in occipital area in people with GAD can increase the global functioning level and can reduce symptoms of generalized anxiety disorder in a treatment group, but no such change was observed in the waiting list group. Increase of alpha and theta brain waves amplitude in occipital area can be useful in the treatment of people with GAD.

  7. Immediate effects of Alpha/theta and Sensory-Motor Rhythm feedback on music performance.

    Science.gov (United States)

    Gruzelier, J H; Hirst, L; Holmes, P; Leach, J

    2014-07-01

    This is one of a series of investigations comparing two EEG-neurofeedback protocols - Alpha/theta (A/T) and Sensory-Motor Rhythm (SMR) - for performance enhancement in the Arts, here with the focus on music. The original report (Egner and Gruzelier, 2003) established a beneficial outcome for elite conservatoire musicians following A/T training in two investigations. Subsequently this A/T advantage was replicated for both advanced instrumental and novice singing abilities, including improvisation, while SMR training benefited novice performance only (Gruzelier, Holmes et al., 2014). Here we report a replication of the latter study in university instrumentalists who as before were novice singers with one design change - post-training performances were conducted within the tenth final session instead of on a subsequent occasion. As before expert judges rated the domains of Creativity/Musicality, Communication/Presentation and Technique. The proximity to training of the music performances within the last session likely compromised gains from A/T learning, but perhaps reinforced the impact of SMR training efficacy. In support of validation there was evidence of strong within- and across-session A/T learning and positive linear trends for across-session SMR/theta and SMR/beta-2 ratio learning. In support of mediation learning correlated with music performance. The A/T outcome was markedly discrepant from previous studies and should dispel any impression that the hypnogogic state itself is transferred to the performance context. The effects of SMR ratio training are consistent with an impact on lower-order abilities required in novice performance such as sustained attention and memory, and benefiting all three domains of music assessment. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Global Heat Kernel Estimates for $\\Delta+\\Delta^{\\alpha/2}$ in Half-space-like domains

    CERN Document Server

    Chen, Zhen-Qing; Song, Renming

    2011-01-01

    Suppose that $d\\ge 1$ and $\\alpha\\in (0, 2)$. In this paper, by using probabilistic methods, we establish sharp two-sided pointwise estimates for the Dirichlet heat kernels of $\\{\\Delta+ a^\\alpha \\Delta^{\\alpha/2}; \\ a\\in (0, 1]\\}$ on half-space-like $C^{1, 1}$ domains in ${\\mathbb R}^d$ for all time $t>0$. The large time estimates for half-space-like domains are very different from those for bounded domains. Our estimates are uniform in $a \\in (0, 1]$ in the sense that the constants in the estimates are independent of $a\\in (0, 1]$. Thus it yields the Dirichlet heat kernel estimates for Brownian motion in half-space-like domains by taking $a\\to 0$. Integrating the heat kernel estimates in time $t$, we obtain uniform sharp two-sided estimates for the Green functions of $\\{\\Delta+ a^\\alpha \\Delta^{\\alpha/2}; \\ a\\in (0, 1]\\}$ in half-space-like $C^{1, 1}$ domains in ${\\mathbb R}^d$.

  9. THETA AND ALPHA EEG FREQUENCY INTERPLAY IN SUBJECTS WITH MILD COGNITIVE IMPAIRMENT: EVIDENCE FROM EEG, MRI AND SPECT BRAIN MODIFICATIONS

    Directory of Open Access Journals (Sweden)

    Davide Vito Moretti

    2015-03-01

    Full Text Available Background: reduction of regional cerebral perfusion in hippocampus as well as temporo-parietal and medial temporal cortex atrophy are associated to mild cognitive impairment (MCI due to Alzheimer disease (AD. Methods: 74 adult subjects with MCI underwent clinical and neuropsychological evaluation, electroencephalogram (EEG recording and high resolution 3D magnetic resonance imaging (MRI. Among the patients, a subset of 27 subjects underwent also perfusion single-photon emission computed tomography (SPECT and hippocampal atrophy evaluation. Alpha3/alpha2 power ratio as well as cortical thickness was computed for each subject. Three MCI groups were detected according to increasing tertile values of alpha3/alpha2 power ratio and difference of cortical thickness among the groups estimated. Results: higher alpha3/alpha2 power ratio group had wider cortical thinning than other groups, mapped to the Supramarginal and Precuneus bilaterally. Subjects with higher alpha3/alpha2 frequency power ratio showed a constant trend to a lower perfusion than lower alpha3/alpha2 group. Moreover, this group correlates with both a bigger hippocampal atrophy and an increase of theta frequency power.Conclusion: Higher EEG alpha3/alpha2 power ratio was associated with temporo-parietal cortical thinning, hippocampal atrophy and reduction of regional cerebral perfusion in medial temporal cortex. In this group an increase of theta frequency power was detected inMCI subjects. The combination of higher EEG alpha3/alpha2 power ratio, cortical thickness measure and regional cerebral perfusion reveals a complex interplay between EEG cerebral rhythms, structural and functional brain modifications.

  10. A theory of alpha/theta neurofeedback, creative performance enhancement, long distance functional connectivity and psychological integration.

    Science.gov (United States)

    Gruzelier, John

    2009-02-01

    Professionally significant enhancement of music and dance performance and mood has followed training with an EEG-neurofeedback protocol which increases the ratio of theta to alpha waves using auditory feedback with eyes closed. While originally the protocol was designed to induce hypnogogia, a state historically associated with creativity, the outcome was psychological integration, while subsequent applications focusing on raising the theta-alpha ratio, reduced depression and anxiety in alcoholism and resolved post traumatic stress syndrome (PTSD). In optimal performance studies we confirmed associations with creativity in musical performance, but effects also included technique and communication. We extended efficacy to dance and social anxiety. Diversity of outcome has a counterpart in wide ranging associations between theta oscillations and behaviour in cognitive and affective neuroscience: in animals with sensory-motor activity in exploration, effort, working memory, learning, retention and REM sleep; in man with meditative concentration, reduced anxiety and sympathetic autonomic activation, as well as task demands in virtual spatial navigation, focussed and sustained attention, working and recognition memory, and having implications for synaptic plasticity and long term potentiation. Neuroanatomical circuitry involves the ascending mescencephalic-cortical arousal system, and limbic circuits subserving cognitive as well as affective/motivational functions. Working memory and meditative bliss, representing cognitive and affective domains, respectively, involve coupling between frontal and posterior cortices, exemplify a role for theta and alpha waves in mediating the interaction between distal and widely distributed connections. It is posited that this mediation in part underpins the integrational attributes of alpha-theta training in optimal performance and psychotherapy, creative associations in hypnogogia, and enhancement of technical, communication and

  11. Genomic organization of the human T-cell antigen-receptor alpha/delta locus.

    Science.gov (United States)

    Satyanarayana, K; Hata, S; Devlin, P; Roncarolo, M G; De Vries, J E; Spits, H; Strominger, J L; Krangel, M S

    1988-11-01

    Two clusters of overlapping cosmid clones comprising about 100 kilobases (kb) at the human T-cell antigen-receptor alpha/delta locus were isolated from a genomic library. The structure of the germ-line V delta 1 variable gene segment was determined. V delta 1 is located 8.5 kb downstream of the V alpha 13.1 gene segment, and both V segments are arranged in the same transcriptional orientation. The V alpha 17.1 segment is located between V delta 1 and the D delta, J delta, C delta region (containing the diversity, joining, and constant gene segments). Thus, V delta and V alpha segments are interspersed along the chromosome. The germ-line organization of the D delta 2, J delta 1, and J delta 2 segments was determined. Linkage of C delta to the J alpha region was established by identification of J alpha segments within 20 kb downstream of C delta. The organization of the locus was also analyzed by field-inversion gel electrophoresis. The unrearranged V delta 1 and D delta, J delta, C delta regions are quite distant from each other, apparently separated by a minimum of 175-180 kb.

  12. Theta and Alpha Oscillations during the Retention Period of Working Memory by rTMS Stimulating the Parietal Lobe.

    Science.gov (United States)

    Li, Song; Jin, Jing-Na; Wang, Xin; Qi, Hong-Zhi; Liu, Zhi-Peng; Yin, Tao

    2017-01-01

    Studies on repetitive transcranial magnetic stimulation (rTMS) have shown that stimulating the parietal lobe, which plays a role in memory storage, can enhance performance during the "retention" process of working memory (WM). However, the mechanism of rTMS effect during this phase is still unclear. In this study, we stimulated the superior parietal lobe (SPL) using 5-Hz rTMS in 26 participants and recorded electroencephalography (EEG) while they performed a delayed-recognition WM task. The analyses included the comparisons of event-related spectral perturbation (ERSP) value variations in theta (4-7 Hz) and alpha (8-14 Hz) band frequencies between conditions (rTMS vs. sham), as well as the correlations between different brain areas. Following rTMS, the ERSP values of theta-band oscillations were significantly increased in the parietal and occipital-parietal brain areas (P parietal area (P parietal and left prefrontal areas were positively correlated with the response time (RT) variations (by using rTMS, the more subject RT decreased, the more ERSP value of theta oscillation increased). The ERSP value variations of alpha-band oscillations in the left parietal and bilateral prefrontal areas were negatively correlated with RT variations (by using rTMS, the more RT of the subject decreased, the more ERSP value of alpha oscillation decreased). Inter-sites phase synchronization of theta-band EEG between the left parietal and left prefrontal areas, as well as alpha-band EEG between the left parietal and bilateral prefrontal areas were enhanced by rTMS. These results indicated that activities of both parietal and prefrontal areas were required for information storage, and these activities were related to the behavioral responses. Moreover, the connectivity between these two regions was intensified following rTMS. Thus, rTMS may affect the frontal area indirectly via the frontal parietal pathway.

  13. Theta and Alpha Oscillations during the Retention Period of Working Memory by rTMS Stimulating the Parietal Lobe

    Directory of Open Access Journals (Sweden)

    Song Li

    2017-09-01

    Full Text Available Studies on repetitive transcranial magnetic stimulation (rTMS have shown that stimulating the parietal lobe, which plays a role in memory storage, can enhance performance during the “retention” process of working memory (WM. However, the mechanism of rTMS effect during this phase is still unclear. In this study, we stimulated the superior parietal lobe (SPL using 5-Hz rTMS in 26 participants and recorded electroencephalography (EEG while they performed a delayed-recognition WM task. The analyses included the comparisons of event-related spectral perturbation (ERSP value variations in theta (4–7 Hz and alpha (8–14 Hz band frequencies between conditions (rTMS vs. sham, as well as the correlations between different brain areas. Following rTMS, the ERSP values of theta-band oscillations were significantly increased in the parietal and occipital-parietal brain areas (P < 0.05*, whereas the ERSP values of alpha-band oscillations were significantly decreased in the parietal area (P < 0.05*. The ERSP value variations of theta-band oscillations between the two conditions in the left parietal and left prefrontal areas were positively correlated with the response time (RT variations (by using rTMS, the more subject RT decreased, the more ERSP value of theta oscillation increased. The ERSP value variations of alpha-band oscillations in the left parietal and bilateral prefrontal areas were negatively correlated with RT variations (by using rTMS, the more RT of the subject decreased, the more ERSP value of alpha oscillation decreased. Inter-sites phase synchronization of theta-band EEG between the left parietal and left prefrontal areas, as well as alpha-band EEG between the left parietal and bilateral prefrontal areas were enhanced by rTMS. These results indicated that activities of both parietal and prefrontal areas were required for information storage, and these activities were related to the behavioral responses. Moreover, the connectivity

  14. Altered Intermittent Rhythmic Delta and Theta Activity in the Electroencephalographies of High Functioning Adult Patients with Autism Spectrum Disorder

    Science.gov (United States)

    Endres, Dominique; Maier, Simon; Feige, Bernd; Posielski, Nicole A.; Nickel, Kathrin; Ebert, Dieter; Riedel, Andreas; Philipsen, Alexandra; Perlov, Evgeniy; Tebartz van Elst, Ludger

    2017-01-01

    Background: Autism spectrum disorder (ASD) is often associated with epilepsy. Previous studies have also shown increased rates of electroencephalographic (EEG) alteration in ASD patients without epilepsy. The aim of this study was to compare the rate of intermittent rhythmic delta and theta activity (IRDA/IRTA) events between high-functioning adult patients with ASD and matched healthy controls. Materials and Methods: Routine EEG records of 19 ASD patients and 19 matched controls were screened for IRDA/IRTA using a fully data driven analysis with fixed thresholds. IRDA/IRTA rates before and after hyperventilation (HV) as well as the HV-induced difference in IRDA/IRTA rates (HV difference) were analyzed. For inter-group measures, we used the Wilcoxon rank sum test. Results: Significantly increased HV difference was detected in the ASD group (p = 0.0497). However, the groups showed no difference in IRDA/IRTA rates before HV (p = 0.564) and after HV (p = 0.163). Conclusions: The lack of any group differences regarding IRDA/IRTA before HV might be related to the fact that we only studied non-secondary high-functioning autism in a small sample of epilepsy-free adult patients. A significantly increased HV difference might be regarded as a marker of subtle neuronal network instability possibly causing short-term disturbances via local area network inhibition and long-term effects via epileptic encephalopathy. PMID:28265243

  15. Thalamic mechanisms underlying alpha-delta sleep with implications for fibromyalgia.

    Science.gov (United States)

    Vijayan, Sujith; Klerman, Elizabeth B; Adler, Gail K; Kopell, Nancy J

    2015-09-01

    Alpha-delta sleep is the abnormal intrusion of alpha activity (8- to 13-Hz oscillations) into the delta activity (1- to 4-Hz oscillations) that defines slow-wave sleep. Alpha-delta sleep is especially prevalent in fibromyalgia patients, and there is evidence suggesting that the irregularities in the sleep of these patients may cause the muscle and tissue pain that characterizes the disorder. We constructed a biophysically realistic mathematical model of alpha-delta sleep. Imaging studies in fibromyalgia patients suggesting altered levels of activity in the thalamus motivated a thalamic model as the source of alpha activity. Since sodium oxybate helps to alleviate the symptoms of fibromyalgia and reduces the amount of alpha-delta sleep in fibromyalgia patients, we examined how changes in the molecular targets of sodium oxybate affected alpha-delta activity in our circuit. Our model shows how alterations in GABAB currents and two thalamic currents, Ih (a hyperpolarization-activated current) and a potassium leak current, transform a circuit that normally produces delta oscillations into one that produces alpha-delta activity. Our findings suggest that drugs that reduce Ih conductances and/or increase potassium conductances, without necessarily increasing GABAB conductances, might be sufficient to restore delta sleep. Furthermore, they suggest that delta sleep might be restored by drugs that preferentially target these currents in the thalamus; such drugs might have fewer side effects than drugs that act systemically.

  16. A Randomized Trial of Comparing the Efficacy of Two Neurofeedback Protocols for Treatment of Clinical and Cognitive Symptoms of ADHD: Theta Suppression/Beta Enhancement and Theta Suppression/Alpha Enhancement

    Directory of Open Access Journals (Sweden)

    Arash Mohagheghi

    2017-01-01

    Full Text Available Introduction. Neurofeedback (NF is an adjuvant or alternative therapy for children with Attention Deficit Hyperactivity Disorder (ADHD. This study intended to compare the efficacy of two different NF protocols on clinical and cognitive symptoms of ADHD. Materials and Methods. In this clinical trial, sixty children with ADHD aged 7 to 10 years old were randomly grouped to receive two different NF treatments (theta suppression/beta enhancement protocol and theta suppression/alpha enhancement protocol. Clinical and cognitive assessments were conducted prior to and following the treatment and also after an eight-week follow-up. Results. Both protocols alleviated the symptoms of ADHD in general (p<0.001, hyperactivity (p<0.001, inattention (p<0.001, and omission errors (p<0.001; however, they did not affect the oppositional and impulsive scales nor commission errors. These effects were maintained after an eight-week intervention-free period. The only significant difference between the two NF protocols was that high-frequency alpha enhancement protocol performed better in suppressing omission errors (p<0.001. Conclusion. The two NF protocols with theta suppression/beta enhancement and theta suppression/alpha enhancement have considerable and comparable effect on clinical symptoms of ADHD. Alpha enhancement protocol was more effective in suppressing omission errors.

  17. Detection of a T cell receptor delta chain with an anti-TCR alpha chain serum.

    Science.gov (United States)

    Leca, G; Bories, J C; Davi, F; Bensussan, A

    1990-04-01

    Two types of T cell antigen-specific receptors have been described. Most peripheral blood T lymphocytes express, at their surface, an antigen receptor consisting of alpha and beta subunits, while a small subset of thymocytes and a minority of mature T lymphocytes express a heterodimeric receptor termed gamma delta. Whereas the gene segments localization corresponding to the TCR gamma and beta chains are separate, genes encoding the joining and the constant regions of TCR delta chain are located between the TCR V alpha region and the J alpha-C alpha gene cluster. To determine whether V alpha gene segments are used by delta chains, immunoprecipitations from human TCR gamma delta expressing cell clones were performed with an anti-alpha serum. The results show that a rabbit antiserum raised against the purified REX TCR alpha subunit immunoprecipitates a TCR delta chain from the cell surface of only one human T cell clone termed SO1. However, since no SO1 RNA hybridization is observed with REX TCR V alpha probe and SO1 cloned cells do react with an anti-V delta 2 monoclonal antibody, we conclude that TCR delta and alpha chains expressed a limited structural homology and that REX TCR V alpha gene do not seem to be frequently used in a functional delta chain.

  18. To Know or Not to Know? Theta and Delta Reflect Complementary Information about an Advanced Cue before Feedback in Decision-Making

    Science.gov (United States)

    Wang, Jing; Chen, Zhaofeng; Peng, Xiaozhe; Yang, Tiantian; Li, Peng; Cong, Fengyu; Li, Hong

    2016-01-01

    To investigate brain activity during the reinforcement learning process in social contexts is a topic of increasing research interest. Previous studies have mainly focused on using electroencephalograms (EEGs) for feedback evaluation in reinforcement learning tasks by measuring event-related potentials. Few studies have investigated the time–frequency (TF) profiles of a cue that manifested whether a following feedback is available or not after decision-making. Moreover, it remains unclear whether the TF profiles of the cue interact with different agents to whom the feedback related. In this study we used the TF approach to test EEG oscillations of the cue stimuli in three agents (‘Self’, ‘Other’, and ‘Computer’) conditions separately. The results showed that the increased central-posterior delta power was elicited by the feedback unavailable cues more so than with the feedback available cue within 200–350 ms after the onset of the cue, but only in the self-condition. Moreover, a frontal-central theta oscillation had enhanced power when following the feedback unavailable cue as opposed to the feedback available cue across three agencies. These findings demonstrated that the cue for knowing an outcome produced reward prediction error-like signals, which were mirrored by the delta and theta oscillations during decision-making. More importantly, the present study demonstrated that the theta and delta oscillations reflected separable components of the advanced cue processing before the feedback in decision-making.

  19. To know or not to know? Theta and delta reflect complementary information about an advanced cue before feedback in decision-making

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2016-10-01

    Full Text Available To investigate brain activity during the reinforcement learning process in social contexts is a topic of increasing research interest. Previous studies have mainly focused on using electroencephalograms (EEG for feedback evaluation in reinforcement learning tasks by measuring event related potentials (ERPs. Few studies have investigated the time-frequency (TF profiles of a cue that manifested whether a following feedback is available or not after decision-making. Moreover, it remains unclear whether the TF profiles of the cue interacts with different agents to whom the feedback related. In this study we used the TF approach to test EEG oscillations of the cue stimuli in three agents (‘Self’, ‘Other’, and ‘Computer’ conditions separately. The results showed that the increased central-posterior delta power was elicited by the feedback unavailable cues more so than with the feedback available cue within 200-350 ms after the onset of the cue, but only in the self-condition. Moreover, a frontal-central theta oscillation had enhanced power when following the feedback unavailable cue as opposed to the feedback available cue across three agencies. These findings demonstrated that the cue for knowing an outcome produced reward prediction error (RPE-like signals, which were mirrored by the delta and theta oscillations during decision-making. More importantly, the present study demonstrated that the theta and delta oscillations reflected separable components of the advanced cue processing before the feedback in decision-making.

  20. Application of alpha/theta neurofeedback and heart rate variability training to young contemporary dancers: state anxiety and creativity.

    Science.gov (United States)

    Gruzelier, J H; Thompson, T; Redding, E; Brandt, R; Steffert, T

    2014-07-01

    As one in a series on the impact of EEG-neurofeedback in the performing arts, we set out to replicate a previous dance study in which alpha/theta (A/T) neurofeedback and heart rate variability (HRV) biofeedback enhanced performance in competitive ballroom dancers compared with controls. First year contemporary dance conservatoire students were randomised to the same two psychophysiological interventions or a choreology instruction comparison group or a no-training control group. While there was demonstrable neurofeedback learning, there was no impact of the three interventions on dance performance as assessed by four experts. However, HRV training reduced anxiety and the reduction correlated with improved technique and artistry in performance; the anxiety scale items focussed on autonomic functions, especially cardiovascular activity. In line with the putative impact of hypnogogic training on creativity A/T training increased cognitive creativity with the test of unusual uses, but not insight problems. Methodological and theoretical implications are considered.

  1. Detection and quantification of residual alpha-phase in delta-stabilized plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Daniel S [Los Alamos National Laboratory; Mitchell, Jeremy N [Los Alamos National Laboratory; Pereyra, Ramiro A [Los Alamos National Laboratory

    2009-01-01

    The temperature range of the {delta}-phase field of plutonium can be expanded by alloying with Group IIIA elements. Ga is a particularly potent {delta}-stabilizer and effectively stabilizes the {delta}-phase to room temperature. Due to a strong propensity towards solute redistribution during cooling through the {var_epsilon} {yields} {delta} phase field, regions of the material often do not contain enough solute to stabilize the {delta}-phase even after extensive homogenization annealing in the {delta}-phase field . The result is a small but persistent, fraction of {alpha}-phase in the material. A technique using differential scanning calorimetry to measure the enthalpy of transformation of the plutonium {alpha} {yields} {beta} transformation is described which can detect and quantify {alpha}-phase in a {delta}-phase matrix at levels as low as {approx} 0.1 wt. %. A set of Pu-1.7 atomic % Ga alloys was examined using the technique and found to contain 0.32 {+-} 0.06 weight % {alpha}-phase. Complications arise due to interference from the pressure-induced {alpha}{prime}-phase, and a peak separation method was developed to accurately measure the heat signal from each phase. Due to the presence of Ga in the {alpha}-phase, the onset temperature of the {alpha} {yields} {beta} transformation in these specimens was found to be 140.2 C, significantly higher than that for the transformation in pure plutonium, 126.2 C.

  2. THETA-Rhythm Makes the World Go Round: Dissociative Effects of TMS Theta Versus Alpha Entrainment of Right pTPJ on Embodied Perspective Transformations.

    Science.gov (United States)

    Gooding-Williams, Gerard; Wang, Hongfang; Kessler, Klaus

    2017-03-03

    Being able to imagine another person's experience and perspective of the world is a crucial human ability and recent reports suggest that humans "embody" another's viewpoint by mentally rotating their own body representation into the other's orientation. Our recent Magnetoencephalography (MEG) data further confirmed this notion of embodied perspective transformations and pinpointed the right posterior temporo-parietal junction (pTPJ) as the crucial hub in a distributed network oscillating at theta frequency (3-7 Hz). In a subsequent transcranial magnetic stimulation (TMS) experiment we interfered with right pTPJ processing and observed a modulation of the embodied aspects of perspective transformations. While these results corroborated the role of right pTPJ, the notion of theta oscillations being the crucial neural code remained a correlational observation based on our MEG data. In the current study we therefore set out to confirm the importance of theta oscillations directly by means of TMS entrainment. We compared entrainment of right pTPJ at 6 Hz vs. 10 Hz and confirmed that only 6 Hz entrainment facilitated embodied perspective transformations (at 160° angular disparity) while 10 Hz slowed it down. The reverse was true at low angular disparity (60° between egocentric and target perspective) where a perspective transformation was not strictly necessary. Our results further corroborate right pTPJ involvement in embodied perspective transformations and highlight theta oscillations as a crucial neural code.

  3. Biosynthesis of Tcr-alpha, beta and Tcr-gamma, delta/CD3 complexes

    DEFF Research Database (Denmark)

    Bauguil-Caspar, S; Arnaud, J; Kuhlmann, J;

    1993-01-01

    Jurkat J76 clone, LYON L12.37 clone and L12.37 cells transfected with J76-alpha cDNA or J76 Tcr-alpha mutated cDNA (J79) were analysed for membrane expression of Tcr/CD3 complex using WT31 mAb (Tcr-alpha, beta) or Tcr-delta 1 mAb (Tcr-gamma, delta): LYON cells express V beta 9 bearing Tcr-beta...... chains. J76 Tcr-alpha cDNA transfected LYON cells have intracellular Tcr-gamma, delta chains and J79 Tcr-alpha cDNA transfected LYON cells have intracellular Tcr-alpha (M), beta chains....

  4. INCREASE OF THETA FREQUENCY IS ASSOCIATED WITH REDUCTION IN REGIONAL CEREBRAL BLOOD FLOW ONLY IN SUBJECTS WITH MILD COGNITIVE IMPAIRMENT WITH HIGHER UPPER ALPHA/LOW ALPHA EEG FREQUENCY POWER RATIO

    Directory of Open Access Journals (Sweden)

    Davide v Moretti

    2013-12-01

    Full Text Available Background: several biomarkers have been proposed for detecting Alzheimer's disease (AD in its earliest stages, that is, in the predementia stage. In an attempt to find noninvasive biomarkers, researchers have investigated the feasibility of neuroimaging tools, such as MRI, SPECT as well as neurophysiological measurements using EEG. Moreover, the increase of EEG alpha3/alpha2 frequency power ratio has been associated with AD-converters subjects with mild cognitive impairment (MCI.Objective: to study the association of alpha3/alpha2 frequency power ratio with regional cerebral blood flow (rCBF changes in subjects with MCI .Methods: 27 adult subjects with MCI underwent EEG recording and perfusion single-photon emission computed tomography (SPECT evaluation. The alpha3/alpha2 frequency power ratio was computed for each subject. Two groups were obtained according to the median values of alpha3/alpha2, at a cut-off of 1.17. Correlation between brain perfusion and EEG markers were detected.Results: subjects with higher alpha3/alpha2 frequency power ratio showed a constant trend to a lower perfusion than low alpha3/alpha2 group. The two groups were significantly different as about the hippocampal volume and correlation with the theta frequency activity.Conclusion: there is a complex interplay between cerebral blood flow, theta frequency activity and hippocampal volume in MCI patients with prodromal Alzheimer's disease, characterized by higher EEG alpha3 /alpha2 frequency power ratio.

  5. Coping food craving with neurofeedback. Evaluation of the usefulness of alpha/theta training in a non-clinical sample.

    Science.gov (United States)

    Imperatori, Claudio; Valenti, Enrico Maria; Della Marca, Giacomo; Amoroso, Noemi; Massullo, Chiara; Carbone, Giuseppe Alessio; Maestoso, Giulia; Quintiliani, Maria Isabella; Contardi, Anna; Farina, Benedetto

    2017-02-01

    The aim of the present study was to explore the usefulness of the alpha/theta (A/T) training in reducing Food Craving (FC) in a non-clinical sample. The modifications of electroencephalographic (EEG) power spectra associated with A/T training was also investigated. Fifty subjects were enrolled in the study and randomly assigned to receive ten sessions of A/T training [neurofeedback group (NFG)=25], or to act as controls [waiting list group (WLG)=25]. All participants were administered the Food Cravings Questionnaire-Trait, the Eating Disorder Examination Questionnaire and the Symptom Checklist-90-Revised. In the post training assessment, compared to the WLG, the NFG showed a significant reduction of intentions and plans to consume food (F1; 49=4.90; p=.033; d=0.626) and of craving as a physiological state (F1; 49=8.09; p=.007; d=803). In NFG, changes in FC persisted after 4months follow-up. Furthermore, A/T training was associated with significant a increase of resting EEG alpha power in several brain areas involved in FC (e.g., insula) and food cue reactivity (e.g., parahippocampal gyrus, inferior and superior temporal gyrus). Taken together, our results showed that ten sessions of A/T training are associated with a decrease of self-reported FC in a non-clinical sample. These findings suggest that this brain-directed intervention may be useful in the treatment of dysfunctional eating behaviors characterized by FC.

  6. Transcriptomic profiling of pancreatic alpha, beta and delta cell populations identifies delta cells as a principal target for ghrelin in mouse islets

    DEFF Research Database (Denmark)

    Adriaenssens, Alice E; Svendsen, Berit; Lam, Brian Y H;

    2016-01-01

    and delta cells. METHODS: Sst-Cre mice crossed with fluorescent reporters were used to identify delta cells, while Glu-Venus (with Venus reported under the control of the Glu [also known as Gcg] promoter) mice were used to identify alpha and beta cells. Alpha, beta and delta cells were purified using flow...... cytometry and analysed by RNA sequencing. The role of the ghrelin receptor was validated by imaging delta cell calcium concentrations using islets with delta cell restricted expression of the calcium reporter GCaMP3, and in perfused mouse pancreases. RESULTS: A database was constructed of all genes...... expressed in alpha, beta and delta cells. The gene encoding the ghrelin receptor, Ghsr, was highlighted as being highly expressed and enriched in delta cells. Activation of the ghrelin receptor raised cytosolic calcium levels in primary pancreatic delta cells and enhanced somatostatin secretion in perfused...

  7. TCR gene segments from at least one third of V alpha subfamilies rearrange at the delta locus.

    Science.gov (United States)

    Genevée, C; Chung, V; Diu, A; Hercend, T; Triebel, F

    1994-02-01

    Using PCR and an experimentally validated V alpha subfamily-specific oligonucleotide panel (V alpha 1-w29), we have investigated whether the TCR delta chain may increase its combinatorial diversity by using V genes considered as alpha chain-specific. We show that at least 10 distinct human V alpha segments rearrange at the J delta locus, leading to scrambling of the two V gene repertoires. Fifty-five per cent of the V alpha/J delta transcripts characterized here were in frame. The 17 V alpha/C delta chains analysed included an extended CDR3 region with up to 18 aa encoded by the junctional region. In addition, a new J delta segment (J delta 4) has been characterized. Together, these findings demonstrate that combinatorial diversity in the human delta locus is larger than previously thought.

  8. Electronic structure of {alpha}- and {delta}-Pu from photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Arko, A. J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Joyce, J. J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Morales, L. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Wills, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Lashley, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Wastin, F. [European Commission, Joint Research Centre, Institute for Transuranic Elements, P.O. Box 2340, D-76175 Karlsruhe, (Germany); Rebizant, J. [European Commission, Joint Research Centre, Institute for Transuranic Elements, P.O. Box 2340, D-76175 Karlsruhe, (Germany)

    2000-07-15

    We report photoemission results on {alpha}- and {delta}-Pu using a laser plasma light source (LPLS) as well as He light as the exciting radiation. The LPLS is a pseudocontinuum tunable light source with intensities rivaling some second-generation synchrotrons. Both phases of Pu display a narrow, temperature-independent, 5f-related feature at the Fermi energy, which is narrower in {delta}-Pu than in {alpha}-Pu, suggestive of possible heavy-fermion-like behavior. In both {alpha}-Pu and {delta}-Pu the photon-energy dependence of this feature suggests some 6d admixture, albeit somewhat smaller in {delta}-Pu. In this respect it differs qualitatively from Ce and U heavy fermions. (c) 2000 The American Physical Society.

  9. Age-related effects on verbal and visuospatial memory are mediated by theta and alpha II rhythms.

    Science.gov (United States)

    Reichert, Johanna Louise; Kober, Silvia Erika; Witte, Matthias; Neuper, Christa; Wood, Guilherme

    2016-01-01

    Both electrical brain activity during rest and memory functions change across the lifespan. Moreover, electrical brain activity is associated with memory functions. However, the interplay between all these effects has been investigated only scarcely. The present study investigated the extent to which the power of resting-state electroencephalographic (EEG) frequencies mediates the impact of aging on verbal and visuospatial memory. Seventy healthy participants with 22 to 83years of age completed a visuospatial and verbal learning and memory test and provided eyes-open and eyes-closed resting-state EEG data. Robust age-related effects on behavioral and EEG data were observed. Mediation analyses showed that the relative power of the theta (4-8Hz) frequency band in fronto-central locations partly explained the negative age-related effect on delayed recall in the verbal memory task. The relative power of the alpha II (10-12Hz) frequency band in mainly parietal locations partly explained the negative impact of age on immediate and delayed recall in the visuospatial task. Results indicate that spontaneous brain activity carries specific information about aging processes and predicts the level of competence in verbal and visuospatial memory tasks.

  10. Flavor origin of dark matter and its relation with leptonic nonzero $\\theta_{13}$ and Dirac CP phase $\\delta$

    CERN Document Server

    Bhattacharya, Subhaditya; Sahu, Narendra; Sil, Arunansu

    2016-01-01

    We propose a minimal extension of the standard model by including a $U(1)$ flavor symmetry to establish a correlation between the relic abundance of dark matter, measured by WMAP and PLANCK satellite experiments and non-zero value of $\\sin \\theta_{13}$ observed at DOUBLE CHOOZ, Daya Bay, RENO and T2K. The flavour symmetry is allowed to be broken at a high scale to a remnant $\\mathcal{Z}_2$ symmetry, which not only ensures the stability to the dark matter, but also gives rise to a modification to the existing $A_4$-based tri-bimaximal neutrino mixing. This deviation in turn suggests the required non-zero value of $\\sin \\theta_{13}$. We assume the dark matter to be neutral under the existing $A_4$ symmetry while charged under the $U(1)$ flavor symmetry. Hence in this set-up, the non-zero value of $\\sin \\theta_{13}$ predicts the dark matter charge under $U(1)$, which can be tested at various ongoing and future direct and collider dark matter search experiments. We also point out the involvement of nonzero lepton...

  11. DeltaNp73alpha regulates MDR1 expression by inhibiting p53 function.

    Science.gov (United States)

    Vilgelm, A; Wei, J X; Piazuelo, M B; Washington, M K; Prassolov, V; El-Rifai, W; Zaika, A

    2008-04-01

    The p73 protein is a transcription factor and member of the p53 protein family that expresses as a complex variety of isoforms. DeltaNp73alpha is an N-terminally truncated isoform of p73. We found that DeltaNp73 protein is upregulated in human gastric carcinoma suggesting that DeltaNp73 may play an oncogenic role in these tumors. Although it has been shown that DeltaNp73alpha inhibits apoptosis and counteracts the effect of chemotherapeutic drugs, the underlying mechanism by which this p73 isoform contributes to chemotherapeutic drug response remains to be explored. We found that DeltaNp73alpha upregulates MDR1 mRNA and p-glycoprotein (p-gp), which is involved in chemotherapeutic drug transport. This p-gp upregulation was accompanied by increased p-gp functional activity in gastric cancer cells. Our data suggest that upregulation of MDR1 by DeltaNp73alpha is mediated by interaction with p53 at the MDR1 promoter.

  12. Human Neutrophil Elastase Induce Interleukin-10 Expression in Peripheral Blood Mononuclear Cells through Protein Kinase C Theta/Delta and Phospholipase Pathways

    Directory of Open Access Journals (Sweden)

    Jin Kawata

    2016-02-01

    Full Text Available Objective: Neutrophils have an important role in the rapid innate immune response, and the release or active secretion of elastase from neutrophils is linked to various inflammatory responses. Purpose of this study was to determine how the human neutrophil elastase affects the interleukin-10 (IL-10 response in peripheral blood mononuclear cells (PBMC. Materials and Methods: In this prospective study, changes in IL-10 messenger RNA (mRNA and protein expression levels in monocytes derived from human PBMCs were investigated after stimulation with human neutrophil elastase (HNE. A set of inhibitors was used for examining the pathways for IL-10 production induced by HNE. Results: Reverse transcription polymerase chain reaction (RT-PCR showed that stimulation with HNE upregulated IL-10 mRNA expression by monocytes, while the enzyme-linked immunosorbent assay (ELISA revealed an increase of IL-10 protein level in the culture medium. A phospholipase C inhibitor (U73122 partially blunted the induction of IL-10 mRNA expression by HNE, while IL-10 mRNA expression was significantly reduced by a protein kinase C (PKC inhibitor (Rottlerin. A calcium chelator (3,4,5-trimethoxybenzoic acid 8-(diethylaminooctyl ester: TMB-8 inhibited the response of IL-10 mRNA to stimulation by HNE. In addition, pretreatment with a broad-spectrum PKC inhibitor (Ro-318425 partly blocked the response to HNE. Finally, an inhibitor of PKC theta/delta abolished the increased level of IL-10 mRNA expression. Conclusion: These results indicate that HNE mainly upregulates IL-10 mRNA expression and protein production in moncytes via a novel PKC theta/delta, although partially via the conventional PKC pathway.

  13. ISOTHERMAL (DELTA)/(ALPHA-PRIME) TRANSFORMATION AND TTT DIAGRAM IN A PLUTONIUM GALLIUM ALLOY

    Energy Technology Data Exchange (ETDEWEB)

    Oudot, B P; Blobaum, K M; Wall, M A; Schwartz, A J

    2005-11-11

    Differential scanning calorimetry (DSC) is used as an alternative approach to determining the tine-temperature-transformation (TTT) diagram for the martensitic delta to alpha-prime transformation in a Pu-2.0 at% Ga alloy. Previous work suggests that the TTT diagram for a similar alloy exhibits an unusual double-C curve for isothermal holds of less than 100 minutes. Here, we extend this diagram to 18 hours, and confirm the double-C curve behavior. When the sample is cooled prior to the isothermal holds, the delta to alpha-prime transformation is observed as several overlapping exothermic peaks. These peaks are very reproducible, and they are believed to be the result of different kinds of delta to alpha-prime martensitic transformation. This may be due to the presence of different nucleation sites and/or different morphologies.

  14. Structural Basis for Iloprost as a Dual Peroxisome Proliferator-activated Receptor [alpha/delta] Agonist

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Lihua; Lin, Shengchen; Rong, Hui; Zheng, Songyang; Jin, Shikan; Wang, Rui; Li, Yong (Pitt); (Xiamen)

    2012-03-15

    Iloprost is a prostacyclin analog that has been used to treat many vascular conditions. Peroxisome proliferator-activated receptors (PPARs) are ligand-regulated transcription factors with various important biological effects such as metabolic and cardiovascular physiology. Here, we report the crystal structures of the PPAR{alpha} ligand-binding domain and PPAR{delta} ligand-binding domain bound to iloprost, thus providing unambiguous evidence for the direct interaction between iloprost and PPARs and a structural basis for the recognition of PPAR{alpha}/{delta} by this prostacyclin analog. In addition to conserved contacts for all PPAR{alpha} ligands, iloprost also initiates several specific interactions with PPARs using its unique structural groups. Structural and functional studies of receptor-ligand interactions reveal strong functional correlations of the iloprost-PPAR{alpha}/{delta} interactions as well as the molecular basis of PPAR subtype selectivity toward iloprost ligand. As such, the structural mechanism may provide a more rational template for designing novel compounds targeting PPARs with more favorable pharmacologic impact based on existing iloprost drugs.

  15. The measurement of urinary Delta(1)-piperideine-6-carboxylate, the alter ego of alpha-aminoadipic semialdehyde, in Antiquitin deficiency.

    NARCIS (Netherlands)

    Struys, E.A.; Bok, L.A.; Emal, D.; Houterman, S.; Willemsen, M.A.A.P.; Jakobs, C.

    2012-01-01

    The assessment of urinary alpha-aminoadipic semialdehyde (alpha-AASA) has become the diagnostic laboratory test for pyridoxine dependent seizures (PDS). alpha-AASA is in spontaneous equilibrium with its cyclic form Delta(1)-piperideine-6-carboxylate (P6C); a molecule with a heterocyclic ring structu

  16. Positive Emotional Experience: Induced by Vibroacoustic Stimulation Using a Body Monochord in Patients with Psychosomatic Disorders: Is Associated with an Increase in EEG-Theta and a Decrease in EEG-Alpha Power.

    Science.gov (United States)

    Sandler, H; Tamm, S; Fendel, U; Rose, M; Klapp, B F; Bösel, R

    2016-07-01

    Relaxation and meditation techniques are generally characterized by focusing attention, which is associated with an increase of frontal EEG Theta. Some studies on music perception suggest an activation of Frontal Midline Theta during emotionally positive attribution, others display a lateralization of electrocortical processes in the attribution of music induced emotion of different valence. The present study examined the effects of vibroacoustic stimulation using a Body Monochord and the conventional relaxation music from an audio CD on the spontaneous EEG of patients suffering from psychosomatic disorders (N = 60). Each treatment took about 20 min and was presented to the patients in random order. Subjective experience was recorded via self-rating scale. EEG power spectra of the Theta, Alpha-1 and Alpha-2 bands were analysed and compard between the two treatment conditions. There was no lateralization of electrocortical activity in terms of the emotional experience of the musical pieces. A reduction in Alpha-2 power occurred during both treatments. An emotionally positive attribution of the experience of the vibroacoustically induced relaxation state is characterized by a more pronounced release of control. In the context of focused attention this is interpreted as flow experience. The spontaneous EEG showed an increase in Theta power, particularly in the frontal medial and central medial area, and a greater reduction in Alpha-2 power. The intensity of positive emotional feelings during the CD music showed no significant effect on the increase in Theta power.

  17. Free radical interaction between vitamin E (alpha-, beta-, gamma- and delta-tocopherol), ascorbate and flavonoids.

    Science.gov (United States)

    Kadoma, Yoshinori; Ishihara, Mariko; Okada, Norihisa; Fujisawa, Seiichiro

    2006-01-01

    Despite a large number of previous studies, the mechanism of free radical interaction between vitamin E (VE) (alpha-, beta-, gamma- and delta-tocopherol) and ascorbate or flavonoids as coantioxidants remains unclear. VE, particularly alpha-tocopherol, shows less antioxidant activity against peroxyl radicals, suggesting that VE possesses functions that are independent of its antioxidant/radical-scavenging activity. The synergistic antioxidant effect of VE or L-ascorbyl 2,6-dibutyrate (ASDB, an ascorbate derivative) with the flavonoids (-)-epicatechin (EC) and (-)-epigallocatechin gallate (EGCG) was investigated using the induction period method in the polymerization of methyl methacrylate initiated by thermal decomposition of benzoyl peroxide (an oxygen-centered radical, PhCOO*) under nearly anaerobic conditions. For delta-tocopherol, a synergistic antioxidant effect was observed in the presence of both EC and EGCG, whereas antioxidant activity for alpha-, beta- and gamma-tocopherol was decreased by addition of EC and EGCG. This suggested that the partial regeneration between VE and flavonoids may depend on the chemical structure of VE, i.e., monomethyl, dimethyl, or trimethyl tocol. The regeneration of delta-tocopherol, a monomethyl tocol, by flavonoids may be due to the lower steric effect of tocol. For ASDB, regeneration of vitamin E, which is well-known for a VE/ascorbate mixture, was not observed, possibly due to the anaerobic experimental conditions. The radical interaction between VE and EC, EGCG or ASDB suggests reactivity of VE with biological systems.

  18. Disparate effects of p24alpha and p24delta on secretory protein transport and processing.

    Directory of Open Access Journals (Sweden)

    Jeroen R P M Strating

    Full Text Available BACKGROUND: The p24 family is thought to be somehow involved in endoplasmic reticulum (ER-to-Golgi protein transport. A subset of the p24 proteins (p24alpha(3, -beta(1, -gamma(3 and -delta(2 is upregulated when Xenopus laevis intermediate pituitary melanotrope cells are physiologically activated to produce vast amounts of their major secretory cargo, the prohormone proopiomelanocortin (POMC. METHODOLOGY/PRINCIPAL FINDINGS: Here we find that transgene expression of p24alpha(3 or p24delta(2 specifically in the Xenopus melanotrope cells in both cases causes an effective displacement of the endogenous p24 proteins, resulting in severely distorted p24 systems and disparate melanotrope cell phenotypes. Transgene expression of p24alpha(3 greatly reduces POMC transport and leads to accumulation of the prohormone in large, ER-localized electron-dense structures, whereas p24delta(2-transgenesis does not influence the overall ultrastructure of the cells nor POMC transport and cleavage, but affects the Golgi-based processes of POMC glycomaturation and sulfation. CONCLUSIONS/SIGNIFICANCE: Transgenic expression of two distinct p24 family members has disparate effects on secretory pathway functioning, illustrating the specificity and non-redundancy of our transgenic approach. We conclude that members of the p24 family furnish subcompartments of the secretory pathway with specific sets of machinery cargo to provide the proper microenvironments for efficient and correct secretory protein transport and processing.

  19. Increased prevalence of intermittent rhythmic delta or theta activity (IRDA/IRTA in the electroencephalograms (EEGs of patients with borderline personality disorder

    Directory of Open Access Journals (Sweden)

    Ludger eTebartz Van Elst

    2016-02-01

    Full Text Available Introduction: An increased prevalence of pathological electroencephalography (EEG signals has been reported in patients with borderline personality disorder (BPD. In an elaborative case description of such a patient with intermittent rhythmic delta and theta activity (IRDA/IRTA, the BPD symptoms where linked to the frequency of the IRDAs/IRTAs and vanished with the IRDAs/IRTAs following anticonvulsive therapy. This observation raised a question regarding the prevalence of such EEG abnormalities in BPD patients. The aim of this retrospective study was to identify the frequency of EEG abnormalities in a carefully analyzed psychiatric collective. Following earlier reports, we hypothesized an increased prevalence of EEG abnormalities in BPD patients.Participants and Methods: We recruited 96 consecutive patients with BPD from the archive of a university clinic for psychiatry and psychotherapy, and compared the prevalence of EEG abnormalities to those of 76 healthy controls subjects. The EEGs were rated by three different blinded clinicians, including a consultant specializing in epilepsy from the local epilepsy center.Results: We found a significant increase in the prevalence of IRDAs and IRTAs in BPD patients (14.6% compared to the control subjects (3.9%; p=0.020. Discussion: In this blinded retrospective case-control study, we were able to confirm an increased prevalence of pathological EEG findings (IRDAs/IRTAs only in BPD patients. The major limitation of this study is that the control group was not matched on age and gender. Therefore, the results should be regarded as preliminary findings of an open uncontrolled, retrospective study. Future research performing prospective, controlled studies is needed to verify our findings and answer the question of whether such EEG findings might predict a positive response to anticonvulsive pharmacological treatment.

  20. Two--Loop Anomalous Dimension Matrix for $\\Delta S=1$ Weak Non-Leptonic Decays; 2, ${\\cal O}(\\alpha_e \\alpha_s)$

    CERN Document Server

    Buras, Andrzej J; Lautenbacher, M E; Buras, Andrzej J.; Jamin, Matthias; Lautenbacher, Markus E.

    1993-01-01

    We calculate the $10\\times 10$ two--loop anomalous dimension matrix to order $\\ord(\\alpha_e \\alpha_s)$ in the dimensional regularization scheme with anticommuting $\\gamma_5$ (NDR) which is necessary for the extension of the $\\Delta S=1$ weak Hamiltonian involving electroweak penguins beyond the leading logarithmic approximation. We demonstrate, how a direct calculation of penguin diagrams involving $\\gamma_5$ in closed fermion loops can be avoided thus allowing a consistent calculation of two--loop anomalous dimensions in the simplest renormalization scheme with anticommuting $\\gamma_5$ in $D$ dimensions. We give the necessary one--loop finite terms which allow to obtain the corresponding two--loop anomalous dimension matrix in the HV scheme with non--anticommuting $\\gamma_5$.

  1. Effect of the theta-alpha-Al2O3 transformation on the oxidation behavior of beta-NiAl+Zr

    Science.gov (United States)

    Rybicki, George C.; Smialek, James L.

    1989-01-01

    Isothermal oxidation of NiAl+Zr has been performed over the temperature range of 800-1200 C and studied by TGA, XRD, and SEM. A discontinuous decrease in growth rate of two orders of magnitude was observed at 1000 C due to the formation of alpha-Al2O3 from theta-Al2O3. This transformation also resulted in a dramatic change in the surface morphology of the scales, as a whisker topography was changed into a weblike network of oxide ridges and radial transformation cracks. It is believed that the ridges are evidence for a short-circuit outward aluminum diffusion growth mechanism that has been documented in a number of O-18 tracer studies.

  2. Effect of the theta-alpha-Al2O3 transformation on the oxidation behavior of beta-NiAl+Zr

    Science.gov (United States)

    Rybicki, George C.; Smialek, James L.

    1989-01-01

    Isothermal oxidation of NiAl+Zr has been performed over the temperature range of 800-1200 C and studied by TGA, XRD, and SEM. A discontinuous decrease in growth rate of two orders of magnitude was observed at 1000 C due to the formation of alpha-Al2O3 from theta-Al2O3. This transformation also resulted in a dramatic change in the surface morphology of the scales, as a whisker topography was changed into a weblike network of oxide ridges and radial transformation cracks. It is believed that the ridges are evidence for a short-circuit outward aluminum diffusion growth mechanism that has been documented in a number of O-18 tracer studies.

  3. Replication of elite music performance enhancement following alpha/theta neurofeedback and application to novice performance and improvisation with SMR benefits.

    Science.gov (United States)

    Gruzelier, J H; Holmes, P; Hirst, L; Bulpin, K; Rahman, S; van Run, C; Leach, J

    2014-01-01

    Alpha/theta (A/T) and sensory-motor rhythm (SMR) neurofeedback were compared in university instrumentalists who were novice singers with regard to prepared and improvised instrumental and vocal performance in three music domains: creativity/musicality, technique and communication/presentation. Only A/T training enhanced advanced playing seen in all three domains by expert assessors and validated by correlations with learning indices, strongest with Creativity/Musicality as shown by Egner and Gruzelier (2003). Here A/T gains extended to novice performance - prepared vocal, improvised vocal and instrumental - and were recognised by a lay audience who judged the prepared folk songs. SMR learning correlated positively with Technical Competence and Communication in novice performance, in keeping with SMR neurofeedback's known impact on lower-order processes such as attention, working memory and psychomotor skills. The importance of validation through learning indices was emphasised in the interpretation of neurofeedback outcome.

  4. Premature temporal theta (PT theta).

    Science.gov (United States)

    Hughes, J R; Fino, J J; Hart, L A

    1987-07-01

    A distinctive pattern called premature temporal theta (PT theta) was studied in 436 infants, ranging in age from 24 to 46 weeks. The pattern is seen in early prematurity, maximizes at 29-31 weeks and then diminishes and disappears near term. Usually the pattern is found independently on both temporal areas, but with a right-sided preference. Patients without PT theta or with a significantly low amount had either neurological or non-neurological (medical) conditions. With age there is a tendency for an increase in frequency and a decrease in amplitude. Five different peaks in the amount of this pattern are seen at approximately every month. Unilateral PT theta tends to be seen in older babies, more often on the right side and with an abnormal EEG. An abnormal EEG is usually associated with a delay in both the appearance and disappearance of this wave form. PT theta is also associated mainly with REM or active sleep. A polynomial rather than an exponential or power function best describes these data with changes of age. PT theta may arise from the inferior temporal gyrus and/or especially the transverse gyrus.

  5. Putative EEG measures of social anxiety : Comparing frontal alpha asymmetry and delta-beta cross-frequency correlation

    NARCIS (Netherlands)

    Harrewijn, A.; Van, der Molen M.J.W.; Westenberg, P.M.

    2016-01-01

    The goal of the present study was to examine whether frontal alpha asymmetry and delta-beta cross-frequency correlation during resting state, anticipation, and recovery are electroencephalographic (EEG) measures of social anxiety. For the first time, we jointly examined frontal alpha asymmetry and

  6. Putative EEG measures of social anxiety : Comparing frontal alpha asymmetry and delta-beta cross-frequency correlation

    NARCIS (Netherlands)

    Harrewijn, A.; Van, der Molen M.J.W.; Westenberg, P.M.

    2016-01-01

    The goal of the present study was to examine whether frontal alpha asymmetry and delta-beta cross-frequency correlation during resting state, anticipation, and recovery are electroencephalographic (EEG) measures of social anxiety. For the first time, we jointly examined frontal alpha asymmetry and d

  7. Putative EEG measures of social anxiety: Comparing frontal alpha asymmetry and delta-beta cross-frequency correlation.

    Science.gov (United States)

    Harrewijn, A; Van der Molen, M J W; Westenberg, P M

    2016-12-01

    The goal of the present study was to examine whether frontal alpha asymmetry and delta-beta cross-frequency correlation during resting state, anticipation, and recovery are electroencephalographic (EEG) measures of social anxiety. For the first time, we jointly examined frontal alpha asymmetry and delta-beta correlation during resting state and during a social performance task in high (HSA) versus low (LSA) socially anxious females. Participants performed a social performance task in which they first watched and evaluated a video of a peer, and then prepared their own speech. They believed that their speech would be videotaped and evaluated by a peer. We found that HSA participants showed significant negative delta-beta correlation as compared to LSA participants during both anticipation of and recovery from the stressful social situation. This negative delta-beta correlation might reflect increased activity in subcortical brain regions and decreased activity in cortical brain regions. As we hypothesized, no group differences in delta-beta correlation were found during the resting state. This could indicate that a certain level of stress is needed to find EEG measures of social anxiety. As for frontal alpha asymmetry, we did not find any group differences. The present frontal alpha asymmetry results are discussed in relation to the evident inconsistencies in the frontal alpha asymmetry literature. Together, our results suggest that delta-beta correlation is a putative EEG measure of social anxiety.

  8. Continuous theta burst transcranial magnetic stimulation affects brain functional connectivity.

    Science.gov (United States)

    Dan Cao; Yingjie Li; Ling Wei; Yingying Tang

    2016-08-01

    Prefrontal cortex (PFC) plays an important role in the emotional processing as well as in the functional brain network. Hyperactivity in the right dorsolateral prefrontal cortex (DLPFC) would be found in anxious participants. However, it is still unclear what the role of PFC played in a resting functional network. Continuous theta burst transcranial magnetic stimulation (cTBS) is an effective tool to create virtual lesions on brain regions. In this paper, we applied cTBS over right prefrontal area, and investigated the effects of cTBS on the brain activity for functional connectivity by the method of graph theory. We recorded 64-channels EEG on thirteen healthy participants in the resting condition and emotional tasks before and after 40 s of cTBS. This work focused on the effect of cTBS on cortical activities in the resting condition by calculating the coherence between EEG channels and building functional networks before and after cTBS in the delta, theta, alpha and beta bands. Results revealed that 1) The functional connectivity after cTBS was significantly increased compared with that before cTBS in delta, theta, alpha and beta bands in the resting condition; 2) The efficiency-cost reached the maximum before and after cTBS both with the cost about 0.3 in the bands above, which meant that the information transmission of functional brain network with this cost was highly efficient; 3) the clustering coefficient and path length after cTBS was significantly increased in delta, theta and beta bands. In conclusion, cTBS over PFC indeed enhanced the functional connectivity in the resting condition. In addition, the information transmission in the resting brain network was highly efficient with the cost about 0.3.

  9. Supine posture inhibits cortical activity: Evidence from Delta and Alpha EEG bands.

    Science.gov (United States)

    Spironelli, Chiara; Busenello, Jessica; Angrilli, Alessandro

    2016-08-01

    Past studies have shown consistent evidence that body position significantly affects brain activity, revealing that both head-down and horizontal bed-rest are associated with cortical inhibition and altered perceptual and cognitive processing. The present study investigates the effects of body position on spontaneous, open-eyes, resting-state EEG cortical activity in 32 young women randomly assigned to one of two conditions, seated position (SP) or horizontal bed rest (BR). A between-group repeated-measure experimental design was used, EEG recordings were made from 38 scalp locations, and low-frequency (delta and alpha) amplitudes of the two groups were compared in four different conditions: when both groups (a) were seated (T0), (b) assumed two different body positions (seated vs. supine conditions, immediate [T1] and 120min later [T2]), and (c) were seated again (T3). Overall, the results showed no a priori between-group differences (T0) before experimental manipulation. As expected, delta amplitude, an index of cortical inhibition in awake resting participants, was significantly increased in group BR, revealing both rapid (T1) and mid-term (T2) inhibitory effects of supine or horizontal positions. Instead, the alpha band was highly sensitive to postural transitions, perhaps due to baroreceptor intervention and, unlike the delta band, underwent habituation and decreased after a 2-h bed rest. These results indicate clear-cut differences at rest between the seated and supine positions, thus supporting the view that the role of body position in the differences found between brain metabolic methods (fMRI and PET) in which participants lie horizontally, and EEG-MEG-TMS techniques with participants in a seated position, has been largely underestimated so far.

  10. Multiphysics phase field modeling of hydrogen diffusion and delta-hydride precipitation in alpha-zirconium

    Science.gov (United States)

    Jokisaari, Andrea M.

    Hydride precipitation in zirconium is a significant factor limiting the lifetime of nuclear fuel cladding, because hydride microstructures play a key role in the degradation of fuel cladding. However, the behavior of hydrogen in zirconium has typically been modeled using mean field approaches, which do not consider microstructural evolution. This thesis describes a quantitative microstructural evolution model for the alpha-zirconium/delta-hydride system and the associated numerical methods and algorithms that were developed. The multiphysics, phase field-based model incorporates CALPHAD free energy descriptions, linear elastic solid mechanics, and classical nucleation theory. A flexible simulation software implementing the model, Hyrax, is built on the Multiphysics Object Oriented Simulation Environment (MOOSE) finite element framework. Hyrax is open-source and freely available; moreover, the numerical methods and algorithms that have been developed are generalizable to other systems. The algorithms are described in detail, and verification studies for each are discussed. In addition, analyses of the sensitivity of the simulation results to the choice of numerical parameters are presented. For example, threshold values for the CALPHAD free energy algorithm and the use of mesh and time adaptivity when employing the nucleation algorithm are studied. Furthermore, preliminary insights into the nucleation behavior of delta-hydrides are described. These include a) the sensitivities of the nucleation rate to temperature, interfacial energy, composition and elastic energy, b) the spatial variation of the nucleation rate around a single precipitate, and c) the effect of interfacial energy and nucleation rate on the precipitate microstructure. Finally, several avenues for future work are discussed. Topics encompass the terminal solid solubility hysteresis of hydrogen in zirconium and the effects of the alpha/delta interfacial energy, as well as thermodiffusion, plasticity

  11. "Burst-like" Characteristics of the delta/alpha-prime Phase Transformation in Pu-Ga Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Blobaum, K; Krenn, C; Haslam, J; Wall, M; Schwartz, A

    2003-11-10

    The {delta} to {alpha}' phase transformation in Pu-Ga alloys is intriguing for both scientific and technological reasons. On cooling, the ductile fcc d-phase transforms martensitically to the brittle monoclinic {alpha}'-phase at approximately -120 C (depending on composition). This exothermic transformation involves a 20% volume contraction and a significant increase in resistivity. The reversion of {alpha}' to {delta} involves a large temperature hysteresis beginning just above room temperature. In an attempt to better understand the underlying thermodynamics and kinetics responsible for these unusual features, we examined the {delta}/{alpha}' transformations in a 0.6 wt% Pu-Ga alloy using differential scanning calorimetry (DSC) and resistometry. Both techniques indicate that the martensite start temperature is -120 C and the austenite start temperature is 35 C. The heat of transformation is approximately 3 kJ/mole. During the {alpha}' {yields} {delta} reversion, ''spikes'' and ''steps'' are observed in DSC and resistometry scans, respectively. These spikes and steps are periodic, and their periodicity with respect to temperature does not vary with heating rate. With an appropriate annealing cycle, including a ''rest'' at room temperature, these spikes and steps can be reproduced through many thermal cycles of a single sample.

  12. Phospholipase C-{delta}{sub 1} regulates interleukin-1{beta} and tumor necrosis factor-{alpha} mRNA expression

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eric; Jakinovich, Paul; Bae, Aekyung [Department of Anesthesiology, Health Sciences Center L4 Rm 081, Stony Brook University, Stony Brook, NY 11794 (United States); Rebecchi, Mario, E-mail: Mario.rebecchi@SBUmed.org [Department of Anesthesiology, Health Sciences Center L4 Rm 081, Stony Brook University, Stony Brook, NY 11794 (United States)

    2012-10-01

    Phospholipase C-{delta}{sub 1} (PLC{delta}{sub 1}) is a widely expressed highly active PLC isoform, modulated by Ca{sup 2+} that appears to operate downstream from receptor signaling and has been linked to regulation of cytokine production. Here we investigated whether PLC{delta}{sub 1} modulated expression of the pro-inflammatory cytokines interleukin-1{beta} (IL-1{beta}), tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-6 (IL-6) in rat C6 glioma cells. Expression of PLC{delta}{sub 1} was specifically suppressed by small interfering RNA (siRNA) and the effects on cytokine mRNA expression, stimulated by the Toll-like receptor (TLR) agonist, lipopolysaccharide (LPS), were examined. Real-time polymerase chain reaction (RT-PCR) results showed that PLC{delta}{sub 1} knockdown enhanced expression IL-1{beta} and tumor necrosis factor-{alpha} (TNF-{alpha}) mRNA by at least 100 fold after 4 h of LPS stimulation compared to control siRNA treatment. PLC{delta}{sub 1} knock down caused persistently high Nf{kappa}b levels at 4 h of LPS stimulation compared to control siRNA-treated cells. PLC{delta}{sub 1} knockdown was also associated with elevated nuclear levels of c-Jun after 30 min of LPS stimulation, but did not affect LPS-stimulated p38 or p42/44 MAPK phosphorylation, normally associated with TLR activation of cytokine gene expression; rather, enhanced protein kinase C (PKC) phosphorylation of cellular proteins was observed in the absence of LPS stimulation. An inhibitor of PKC, bisindolylmaleimide II (BIM), reversed phosphorylation, prevented elevation of nuclear c-Jun levels, and inhibited LPS-induced increases of IL-1{beta} and TNF-{alpha} mRNA's induced by PLC{delta}{sub 1} knockdown. Our results show that loss of PLC{delta}{sub 1} enhances PKC/c-Jun signaling and up-modulates pro-inflammatory cytokine gene transcription in concert with the TLR-stimulated p38MAPK/Nf{kappa}b pathway. Our findings are consistent with the idea that PLC{delta}{sub 1} is a

  13. Structural studies on the reaction of isopenicillin N synthase with the substrate analogue delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-alpha-aminobutyrate.

    Science.gov (United States)

    Long, Alexandra J; Clifton, Ian J; Roach, Peter L; Baldwin, Jack E; Schofield, Christopher J; Rutledge, Peter J

    2003-06-15

    Isopenicillin N synthase (IPNS) is a non-haem iron(II) oxidase which catalyses the biosynthesis of isopenicillin N from the tripeptide delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-valine (ACV). Herein we report crystallographic studies to investigate the reaction of IPNS with the truncated substrate analogue delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-alpha-aminobutyrate (ACAb). It has been reported previously that this analogue gives rise to three beta-lactam products when incubated with IPNS: two methyl penams and a cepham. Crystal structures of the IPNS-Fe(II)-ACAb and IPNS-Fe(II)-ACAb-NO complexes have now been solved and are reported herein. These structures and modelling studies based on them shed light on the diminished product selectivity shown by IPNS in its reaction with ACAb and further rationalize the presence of certain key residues at the IPNS active site.

  14. Gene discovery at the human T-cell receptor alpha/delta locus.

    Science.gov (United States)

    Haynes, Marsha R; Wu, Gillian E

    2007-02-01

    The human T-cell receptor (TCR) alpha/delta variable loci are interspersed on the chromosome 14q11 and consist of 57 intergenic spaces ranging from 4 to 100 kb in length. To elucidate the evolutionary history of this locus, we searched the intergenic spaces of all TCR alpha/delta variable (TRAV/DV) genes for pseudogenes and potential protein-coding genes. We applied direct open reading frame (ORF) searches, an exon-finding algorithm and comparative genomics. Two TRAV/DV pseudogenes were discovered bearing 80 and 65% sequence similarity to TRAV14DV4 and TRAV9-1/9-2 genes, respectively. A gene bearing 85% sequence identity to B lymphocyte activation-related protein, BC-1514, upstream of TRAV26-2 was also discovered. This ORF (BC-1514tcra) is a member of a gene family whose evolutionary history and function are not known. In total, 36 analogs of this gene exist in the human, the chimpanzee, the Rhesus monkey, the frog and the zebrafish. Phylogenetic analyses show convergent evolution of these genes. Assays for the expression of BC-1514tcra revealed transcripts in the bone marrow, thymus, spleen, and small intestine. These assays also showed the expression of another analog to BC-1514, found on chromosome 5 in the bone marrow and thymus RNA. The existence of at least 17 analogs at various locations in the human genome and in nonsyntenic chromosomes of the chimpanzee suggest that BC-1514tcra, along with its analogs may be transposable elements with evolved function(s). The identification of conserved putative serine phosphorylation sites provide evidence of their possible role(s) in signal transduction events involved in B cell development and differentiation.

  15. {theta}{sub 13}{sup PMNS}={theta}{sub C}/{radical}(2) from GUTs

    Energy Technology Data Exchange (ETDEWEB)

    Antusch, Stefan, E-mail: stefan.antusch@unibas.ch [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Muenchen (Germany); Gross, Christian, E-mail: christian.gross@unibas.ch [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Maurer, Vinzenz, E-mail: vinzenz.maurer@unibas.ch [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Sluka, Constantin, E-mail: constantin.sluka@unibas.ch [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland)

    2013-01-21

    The recent observations of the leptonic mixing angle {theta}{sub 13}{sup PMNS} are consistent with {theta}{sub 13}{sup PMNS}={theta}{sub C}/{radical}(2) (with {theta}{sub C} being the Cabibbo angle {theta}{sub 12}{sup CKM}). We discuss how this relation can emerge in Grand Unified Theories (GUTs) via charged lepton corrections. The key ingredient is that in GUTs the down-type quark Yukawa matrix and the charged lepton Yukawa matrix are generated from the same set of GUT operators, which implies that the resulting entries are linked and differ only by group-theoretical Clebsch factors. This allows a link {theta}{sub 12}{sup e} Almost-Equal-To {theta}{sub C} to be established, which can induce {theta}{sub 13}{sup PMNS} Almost-Equal-To {theta}{sub C}/{radical}(2) provided that the 1-3 mixing in the neutrino mass matrix is much smaller than {theta}{sub C}. We find simple conditions under which {theta}{sub 13}{sup PMNS} Almost-Equal-To {theta}{sub C}/{radical}(2) can arise via this link in SU(5) GUTs and Pati-Salam models. We also discuss possible corrections to the exact relation. Using lepton mixing sum rules different neutrino mixing patterns can be distinguished by their predictions for the Dirac CP phase {delta}{sup PMNS}.

  16. Neural rhythmic symphony of human walking observation: Upside-down and Uncoordinated condition on cortical theta, alpha, beta and gamma oscillations.

    Directory of Open Access Journals (Sweden)

    David eZarka

    2014-09-01

    Full Text Available Biological motion observation has been recognized to produce dynamic change in sensorimotor activation according to the observed kinematics. Physical plausibility of the spatial-kinematic relationship of human movement may play a major role in the top-down processing of human motion recognition. Here, we investigated the time course of scalp activation during observation of human gait in order to extract and use it on future integrated brain-computer interface using virtual reality (VR. We analyzed event related potentials (ERP, the event related spectral perturbation (ERSP and the inter-trial coherence (ITC from high-density EEG recording during video display onset (-200 to 600 ms and the steady state visual evoked potentials (SSVEP inside the video of human walking 3D-animation in three conditions: Normal; Upside-down (inverted images; and Uncoordinated (pseudo-randomly mixed images. We found that early visual evoked response P120 was decreased in Upside-down condition. The N170 and P300b amplitudes were decreased in Uncoordinated condition. In Upside-down and Uncoordinated conditions, we found decreased alpha power and theta phase-locking. As regards gamma oscillation, power was increased during the Upside-down animation and decreased during the Uncoordinated animation. An SSVEP-like response oscillating at about 10 Hz was also described showing that the oscillating pattern is enhanced 300 ms after the heel strike event only in the Normal but not in the Upside-down condition. Our results are consistent with most of previous point-light display studies, further supporting possible use of virtual reality for neurofeedback applications.

  17. The mouse (Mus musculus) T cell receptor alpha (TRA) and delta (TRD) variable genes.

    Science.gov (United States)

    Bosc, Nathalie; Lefranc, Marie-Paule

    2003-01-01

    'The Mouse (Mus musculus) T cell receptor alpha (TRA) and delta (TRD) variable genes' 'IMGT Locus in Focus' report provides the first complete list of the mouse TRAV and TRDV genes which span 1550 kb on chromosome 14 at 19.7 cM. The total number of TRAV genes per haploid genome is 98 belonging to 23 subgroups. This includes 10 TRAV/DV genes which belong to seven subgroups. The functional TRAV genomic repertoire comprises 72-82 TRAV (including 9-10 TRAV/DV) belonging to 19 subgroups. The total number of TRDV genes per haploid genome is 16 (including the 10 TRAV/DV) belonging to 12 subgroups. The functional TRDV genomic repertoire comprises 14-15 genes (5 TRDV and 9-10 TRAV/DV) belonging to 11-12 subgroups. The eight tables and three figures of this report are available at the IMGT Marie-Paule page of IMGT. The international ImMunoGeneTics information system (http://imgt.cines.fr) created by Marie-Paule Lefranc, Université Montpellier II, CNRS, France.

  18. [Topographic characteristics of cortex activity in delta-, alpha2-, and gamma2- frequency bands related to social creativity].

    Science.gov (United States)

    Razumnikova, O M; Finikov, S B

    2011-01-01

    Social creativity-related topographic changes of the delta, alpha2, and gamma2 power were studied using 19-channel EEG. Originality and fluency indices of social thinking were evaluated on basis of specially developed 'divergent' task solution that stimulated different interpretations of social scenes; complex visual stimuli (architectural building) were used as control task. 'Divergent' task performing was characterized by both the greater power of the delta and alpha2 rhythms mostly in the right hemisphere and widespread increase in the gamma2 power as compared with the control task. Positive correlations between delta and gamma2 rhythms in baseline condition were revealed in the fronto-parietal cortex, and this relationship between low- and high-frequency oscillations while 'divergent' task performing was found in the right posterior cortex. Special topographic patterns of delta and gamma2 activity as predictors of social creativity were obtained using multiple regression analysis. These patterns can be interpreted as EEG correlates of a summation of endogenous and exogenous components of social thinking.

  19. Sheep (Ovis aries) T cell receptor alpha (TRA) and delta (TRD) genes and genomic organization of the TRA/TRD locus

    National Research Council Canada - National Science Library

    Piccinni, Barbara; Massari, Serafina; Caputi Jambrenghi, Anna; Giannico, Francesco; Lefranc, Marie-Paule; Ciccarese, Salvatrice; Antonacci, Rachele

    2015-01-01

    ..."). While the T cell receptor alpha (TRA) and delta (TRD) genes and the genomic organization of the TRA/TRD locus has been determined in human and mouse, this information is still poorly known in artiodactyl species, such as sheep...

  20. Increased frontal electroencephalogram theta amplitude in patients with anorexia nervosa compared to healthy controls

    Directory of Open Access Journals (Sweden)

    Hestad KA

    2016-09-01

    Full Text Available Knut A Hestad,1–3 Siri Weider,3,4 Kristian Bernhard Nilsen,5–7 Marit Sæbø Indredavik,8,9 Trond Sand7,10 1Department of Research, Innlandet Hospital Trust, Brumunddal, Norway; 2Department of Public Health, Hedmark University of Applied Sciences, Elverum, Norway; 3Department of Psychology, Faculty of Social Sciences and Technology Management, Norwegian University of Science and Technology (NTNU, Trondheim, Norway; 4Department of Psychiatry, Specialised Unit for Eating Disorder Patients, Levanger Hospital, Health Trust Nord-Trøndelag, Levanger, Norway; 5Department of Neuroscience, Norwegian University of Science and Technology (NTNU, Trondheim, Norway; 6Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway; 7Department of Neurology, Section for Clinical Neurophysiology, Oslo University Hospital, Ullevål, Oslo, Norway; 8Regional Centre for Child and Youth Mental Health and Child Welfare, Faculty of Medicine, Norwegian University of Science and Technology (NTNU, Trondheim, Norway; 9Department of Child and Adolescent Psychiatry, St Olavs Hospital, Trondheim University Hospital, Trondheim, Norway; 10Department of Neurology and Clinical Neurophysiology, St Olavs Hospital, Trondheim University Hospital, Trondheim, Norway Objective: To conduct a blind study of quantitative electroencephalogram-band amplitudes in patients with anorexia nervosa (AN and healthy controls.Methods: Twenty-one patients with AN and 24 controls were examined with eyes-closed 16-channel electroencephalogram. Main variables were absolute alpha, theta, and delta amplitudes in frontal, temporal, and posterior regions.Results: There were no significant differences between the AN patients and controls regarding absolute regional band amplitudes in µV. Borderline significance was found for anterior theta (P=0.051. Significantly increased left and right frontal electrode theta amplitude was found in AN patients (F3, P=0.014; F4, P

  1. Stoichiometry of expressed alpha(4)beta(2)delta gamma-aminobutyric acid type A receptors depends on the ratio of subunit cDNA transfected.

    Science.gov (United States)

    Wagoner, Kelly R; Czajkowski, Cynthia

    2010-05-07

    The gamma-aminobutyric acid type A receptor (GABA(A)R) is the target of many depressants, including benzodiazepines, anesthetics, and alcohol. Although the highly prevalent alphabetagamma GABA(A)R subtype mediates the majority of fast synaptic inhibition in the brain, receptors containing delta subunits also play a key role, mediating tonic inhibition and the actions of endogenous neurosteroids and alcohol. However, the fundamental properties of delta-containing GABA(A)Rs, such as subunit stoichiometry, are not well established. To determine subunit stoichiometry of expressed delta-containing GABA(A)Rs, we inserted the alpha-bungarotoxin binding site tag in the alpha(4), beta(2), and delta subunit N termini. An enhanced green fluorescent protein tag was also inserted into the beta(2) subunit to shift its molecular weight, allowing us to separate subunits using SDS-PAGE. Tagged alpha(4)beta(2)delta GABA(A)Rs were expressed in HEK293T cells using various ratios of subunit cDNA, and receptor subunit stoichiometry was determined by quantitating fluorescent alpha-bungarotoxin bound to each subunit on Western blots of surface immunopurified tagged GABA(A)Rs. The results demonstrate that the subunit stoichiometry of alpha(4)beta(2)delta GABA(A)Rs is regulated by the ratio of subunit cDNAs transfected. Increasing the ratio of delta subunit cDNA transfected increased delta subunit incorporation into surface receptors with a concomitant decrease in beta(2) subunit incorporation. Because receptor subunit stoichiometry can directly influence GABA(A)R pharmacological and functional properties, considering how the transfection protocols used affect subunit stoichiometry is essential when studying heterologously expressed alpha(4)beta(2)delta GABA(A)Rs. Successful bungarotoxin binding site tagging of GABA(A)R subunits is a novel tool with which to accurately quantitate subunit stoichiometry and will be useful for monitoring GABA(A)R trafficking in live cells.

  2. Realistic Earth matter effects and a method to measure small \\theta_{13} in the detection of supernova neutrinos

    CERN Document Server

    Guo, Xin-Heng; Young, Bing-Lin

    2008-01-01

    In this paper, we first calculate the realistic Earth matter effects on the detection of type II supernova neutrinos at the Daya Bay reactor neutrino experiment which is currently under construction. It is found that the Earth matter effects depend on the neutrino incident angle \\theta, the neutrino mass hierarchy \\Delta m_{31}^{2}, the crossing probability at the high resonance region inside the supernova, P_H, the neutrino temperature, T_{\\alpha}, and the pinching parameter in the neutrino spectrum, \\eta_{\\alpha}. We give the expression for the dependence of P_H on the neutrino mixing angle \\theta_{13}. With this we obtain the relations between \\theta_{13} and the event numbers for various reaction channels of supernova neutrinos. Using these relations, we propose a possible way to measure \\theta_{13} smaller than 1.5^\\circ. Such a sensitivity cannot be achieved by the Daya Bay neutrino experiment (the sensitivity of the Daya Bay experiment is \\theta_{13}\\sim 3^\\circ). Furthermore, we apply this method to o...

  3. The TF1-ATPase and ATPase activities of assembled alpha 3 beta 3 gamma, alpha 3 beta 3 gamma delta, and alpha 3 beta 3 gamma epsilon complexes are stimulated by low and inhibited by high concentrations of rhodamine 6G whereas the dye only inhibits the alpha 3 beta 3, and alpha 3 beta 3 delta complexes.

    Science.gov (United States)

    Paik, S R; Yokoyama, K; Yoshida, M; Ohta, T; Kagawa, Y; Allison, W S

    1993-12-01

    The ATPase activity of the F1-ATPase from the thermophilic bacterium PS3 is stimulated at concentrations of rhodamine 6G up to about 10 microM where 70% stimulation is observed at 36 degrees C. Half maximal stimulation is observed at about 3 microM dye. At rhodamine 6G concentrations greater than 10 microM, ATPase activity declines with 50% inhibition observed at about 75 microM dye. The ATPase activities of the alpha 3 beta 3 gamma and alpha 3 beta 3 gamma delta complexes assembled from isolated subunits of TF1 expressed in E. coli deleted of the unc operon respond to increasing concentrations of rhodamine 6G nearly identically to the response of TF1. In contrast, the ATPase activities of the alpha 3 beta 3 and alpha 3 beta 3 delta complexes are only inhibited by rhodamine 6G with 50% inhibition observed, respectively, at 35 and 75 microM dye at 36 degrees C. The ATPase activity of TF1 is stimulated up to 4-fold by the neutral detergent, LDAO. In the presence of stimulating concentrations of LDAO, the ATPase activity of TF1 is no longer stimulated by rhodamine 6G, but rather, it is inhibited with 50% inhibition observed at about 30 microM dye at 30 degrees C. One interpretation of these results is that binding of rhodamine 6G to a high-affinity site on TF1 stimulates ATPase activity and unmasks a low-affinity, inhibitory site for the dye which is also exposed by LDAO.

  4. delta-(L-alpha-Aminoadipyl)-L-cysteinyl-D-valine synthetase, that mediates the first committed step in penicillin biosynthesis, is a cytosolic enzyme

    NARCIS (Netherlands)

    van der Lende, T.R.; de Kamp, M.; den Berg, M.van; Sjollema, K.; Bovenberg, R.A.L.; Veenhuis, M; Konings, W.N; Driessen, A.J.M.

    2002-01-01

    Penicillin biosynthesis by Penicillium chrysogenum is a compartmentalized process. The first catalytic step is mediated by delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACV synthetase), a high molecular mass enzyme that condenses the amino acids L-alpha-aminoadipate, L-cysteme, and L-

  5. delta-(L-alpha-Aminoadipyl)-L-cysteinyl-D-valine synthetase, that mediates the first committed step in penicillin biosynthesis, is a cytosolic enzyme

    NARCIS (Netherlands)

    van der Lende, T.R.; de Kamp, M.; den Berg, M.van; Sjollema, K.; Bovenberg, R.A.L.; Veenhuis, M; Konings, W.N; Driessen, A.J.M.

    2002-01-01

    Penicillin biosynthesis by Penicillium chrysogenum is a compartmentalized process. The first catalytic step is mediated by delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACV synthetase), a high molecular mass enzyme that condenses the amino acids L-alpha-aminoadipate, L-cysteme, and

  6. Cross-linking of the delta subunit to one of the three alpha subunits has no effect on functioning, as expected if delta is a part of the stator that links the F1 and F0 parts of the Escherichia coli ATP synthase.

    Science.gov (United States)

    Ogilvie, I; Aggeler, R; Capaldi, R A

    1997-06-27

    A mutant of the Escherichia coli F1F0-ATPase has been generated (alphaQ2C) in which the glutamine at position 2 of the alpha subunit has been replaced with a cysteine residue. Cu2+ treatment of ECF1 from this mutant cross-linked an alpha subunit to the delta subunit in high yield. Two different sites of disulfide bond formation were involved, i.e. between Cys90 (or the closely spaced Cys47) of alpha with Cys140 of delta, and between Cys2 of alpha and Cys140 of delta. Small amounts of other cross-linked products, including alpha-alpha, delta internal, and alpha-alpha-delta were obtained. In ECF1F0, there was no cross-linking between the intrinsic Cys of alpha and Cys140. Instead, the product generated between Cys2 of alpha and Cys140 of delta was obtained at near 90% yield. Small amounts of alpha-alpha and delta internal were present, and under high Cu2+ concentrations, alpha-alpha-delta was also formed. The ATPase activity of ECF1 and ECF1F0 was not significantly affected by the presence of these cross-links. When Cys140 of delta was first modified with N-ethylmaleimide in ECF1F0, an alpha-delta cross-link was still produced, although in lower yield, between Cys64 of delta and Cys2 of alpha. ATP hydrolysis-linked proton pumping of inner membranes from the mutant alpha2QC was only marginally affected by cross-linking of the alpha to the delta subunit. These results indicate that Cys140 and Cys64 of the delta subunit and Cys2 of the alpha subunit are in close proximity. This places the delta subunit near the top of the alpha-beta hexagon and not in the stalk region. As fixing the delta to the alpha by cross-linking does not greatly impair either the ATPase function of the enzyme, or coupled proton translocation, we argue that the delta subunit forms a portion of the stator linking F1 to F0.

  7. Structural complex of sterol 14[alpha]-demethylase (CYP51) with 14[alpha]-methylenecyclopropyl-[delta]7-24, 25-dihydrolanosterol[S

    Energy Technology Data Exchange (ETDEWEB)

    Hargrove, Tatiana Y.; Wawrzak, Zdzislaw; Liu, Jialin; Waterman, Michael R.; Nes, W. David; Lepesheva, Galina I. (Vanderbilt); (TTU); (NWU)

    2012-06-28

    Sterol 14{alpha}-demethylase (CYP51) that catalyzes the removal of the 14{alpha}-methyl group from the sterol nucleus is an essential enzyme in sterol biosynthesis, a primary target for clinical and agricultural antifungal azoles and an emerging target for antitrypanosomal chemotherapy. Here, we present the crystal structure of Trypanosoma (T) brucei CYP51 in complex with the substrate analog 14{alpha}-methylenecyclopropyl-{Delta}7-24,25-dihydrolanosterol (MCP). This sterol binds tightly to all protozoan CYP51s and acts as a competitive inhibitor of F105-containing (plant-like) T. brucei and Leishmania (L) infantum orthologs, but it has a much stronger, mechanism-based inhibitory effect on I105-containing (animal/fungi-like) T. cruzi CYP51. Depicting substrate orientation in the conserved CYP51 binding cavity, the complex specifies the roles of the contact amino acid residues and sheds new light on CYP51 substrate specificity. It also provides an explanation for the effect of MCP on T. cruzi CYP51. Comparison with the ligand-free and azole-bound structures supports the notion of structural rigidity as the characteristic feature of the CYP51 substrate binding cavity, confirming the enzyme as an excellent candidate for structure-directed design of new drugs, including mechanism-based substrate analog inhibitors.

  8. Purification and characterization of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase from Penicillium chrysogenum

    DEFF Research Database (Denmark)

    Theilgaard, Hanne Birgitte; Kristiansen, K.N.; Henriksen, Claus Maxel

    1997-01-01

    delta-(L-alpha-Aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) from Penicillium chrysogenum was purified to homogeneity by a combination of (NH4)(2)SO4 precipitation, protamine sulphate treatment, ion-exchange chromatography, gel filtration and hydrophobic interaction chromatography. The mole......delta-(L-alpha-Aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) from Penicillium chrysogenum was purified to homogeneity by a combination of (NH4)(2)SO4 precipitation, protamine sulphate treatment, ion-exchange chromatography, gel filtration and hydrophobic interaction chromatography....... The molecular mass of ACVS was estimated with native gradient gel electrophoresis and SDS/PAGE. The native enzyme consisted of a single polymer chain with an estimated molecular mass of 470 kDa. The denatured enzyme had an estimated molecular mass of 440 kDa. The influence of different reaction parameters...... such as substrates, cofactors and pH on the activity of the purified ACVS was investigated. The K-m values for the three precursor substrates La-aminoadipic acid, L-cysteine and L-valine were determined as 45, 80 and 80 mu M respectively, and the optimal assay concentration of ATP was found to be 5 mM (with 20 mM Mg...

  9. 3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides: potent, non-peptidic agonists of both the micro and delta opioid receptors.

    Science.gov (United States)

    Bishop, Michael J; Garrido, Dulce M; Boswell, G Evan; Collins, Mark A; Harris, Philip A; McNutt, Robert W; O'Neill, Scott J; Wei, Ke; Chang, Kwen-Jen

    2003-02-13

    Opioid analgesics with both micro and delta opioid receptor activation represent a new approach to the treatment of severe pain with an improved safety profile. Compounds with this profile may exhibit strong analgesic properties due to micro agonism, with a reduced side effect profile resulting from delta agonism. Replacing the p-diethylamide of the known potent delta opioid receptor selective agonist BW373U86 with a m-diethylamide resulted in a compound with agonist activity at both the micro and delta opioid receptors. Modifying the amide to an N-methyl-N-phenylamide increased agonist potency at both receptors. A series of 3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides have been made to explore the structure-activity relationship (SAR) around the N-methyl-N-phenylamide. Several potent agonists of both the micro and delta opioid receptors have been identified, including (+)-3-((alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-(4-fluorophenyl)-N-methylbenzamide (23), which has EC50 values of 0.67 and 1.1 nM at the micro (guinea pig ileum assay) and delta (mouse vas deferens assay) opioid receptors, respectively.

  10. DeltaNp63alpha repression of the Notch1 gene supports the proliferative capacity of normal human keratinocytes and cervical cancer cells.

    Science.gov (United States)

    Yugawa, Takashi; Narisawa-Saito, Mako; Yoshimatsu, Yuki; Haga, Kei; Ohno, Shin-ichi; Egawa, Nagayasu; Fujita, Masatoshi; Kiyono, Tohru

    2010-05-15

    The p53 family member p63 is a master regulator of epithelial development. One of its isoforms, DeltaNp63alpha, is predominantly expressed in the basal cells of stratified epithelia and plays a fundamental role in control of regenerative potential and epithelial integrity. In contrast to p53, p63 is rarely mutated in human cancers, but it is frequently overexpressed in squamous cell carcinomas (SCC). However, its functional relevance to tumorigenesis remains largely unclear. We previously identified the Notch1 gene as a novel transcriptional target of p53. Here, we show that DeltaNp63alpha functions as a transcriptional repressor of the Notch1 gene through the p53-responsive element. Knockdown of p63 caused upregulation of Notch1 expression and marked reduction in proliferation and clonogenicity of both normal human keratinocytes and cervical cancer cell lines overexpressing DeltaNp63alpha. Concomitant silencing of Notch1 significantly rescued this phenotype, indicating the growth defect induced by p63 deficiency to be, at least in part, attributable to Notch1 function. Conversely, overexpression of DeltaNp63alpha decreased basal levels of Notch1, increased proliferative potential of normal human keratinocytes, and inhibited both p53-dependent and p53-independent induction of Notch1 and differentiation markers upon genotoxic stress and serum exposure, respectively. These results suggest that DeltaNp63alpha maintains the self-renewing capacity of normal human keratinocytes and cervical cancer cells partly through transcriptional repression of the Notch1 gene and imply a novel pathogenetical significance of frequently observed overexpression of DeltaNp63alpha together with p53 inactivation in SCCs.

  11. Different slopes for different folks: alpha and delta EEG power predict subsequent video game learning rate and improvements in cognitive control tasks.

    Science.gov (United States)

    Mathewson, Kyle E; Basak, Chandramallika; Maclin, Edward L; Low, Kathy A; Boot, Walter R; Kramer, Arthur F; Fabiani, Monica; Gratton, Gabriele

    2012-12-01

    We hypothesized that control processes, as measured using electrophysiological (EEG) variables, influence the rate of learning of complex tasks. Specifically, we measured alpha power, event-related spectral perturbations (ERSPs), and event-related brain potentials during early training of the Space Fortress task, and correlated these measures with subsequent learning rate and performance in transfer tasks. Once initial score was partialled out, the best predictors were frontal alpha power and alpha and delta ERSPs, but not P300. By combining these predictors, we could explain about 50% of the learning rate variance and 10%-20% of the variance in transfer to other tasks using only pretraining EEG measures. Thus, control processes, as indexed by alpha and delta EEG oscillations, can predict learning and skill improvements. The results are of potential use to optimize training regimes. Copyright © 2012 Society for Psychophysiological Research.

  12. Behaviour of alpha-, beta-, gamma-, and delta-hexachlorocyclohexane in the soil-plant system of a contaminated site.

    Science.gov (United States)

    Calvelo Pereira, R; Camps-Arbestain, M; Rodríguez Garrido, B; Macías, F; Monterroso, C

    2006-11-01

    The behaviour of the organochlorine pesticide hexachlorocyclohexane (HCH) is investigated. The concentrations of alpha-, beta-, gamma-, and delta-HCH isomers were measured in soils, rhizosphere and vegetation in a contaminated area in Galicia (NW Spain). The total concentration of HCH in soils reached values close to 20,000 mgkg(-1). The plants analysed (Avena sativa L., Chenopodium spp., Solanum nigrum L., Cytisus striatus (Hill) Roth, and Vicia sativa L.) accumulated HCH, especially the beta-HCH isomer, in their tissues. The most likely mechanisms of HCH accumulation in plants were sorption of soil HCH on roots and sorption of volatilized HCH on aerial plant tissues. The concentrations of HCH obtained from the bulk and rhizosphere soils of selected plant species suggest that roots tend to reduce levels of the HCH isomers in the rhizosphere. The results reflect the importance of vegetation in the distribution of organochlorine compounds in the soil-plant system.

  13. Unlike PPAR{gamma}, PPAR{alpha} or PPAR{beta}/{delta} activation does not promote human monocyte differentiation toward alternative macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Bouhlel, Mohamed Amine [Univ Lille Nord de France, F-59000 Lille (France); Inserm U545, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France); Brozek, John [Genfit, Loos (France); Derudas, Bruno [Univ Lille Nord de France, F-59000 Lille (France); Inserm U545, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France); Zawadzki, Christophe; Jude, Brigitte [Inserm ERI-9 and Equipe d' Accueil 2693, IFR114, Universite de Lille, Lille (France); Staels, Bart, E-mail: bart.staels@pasteur-lille.fr [Univ Lille Nord de France, F-59000 Lille (France); Inserm U545, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France); Chinetti-Gbaguidi, Giulia [Univ Lille Nord de France, F-59000 Lille (France); Inserm U545, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France)

    2009-08-28

    Macrophages adapt their response to micro-environmental signals. While Th1 cytokines promote pro-inflammatory M1 macrophages, Th2 cytokines promote an 'alternative' anti-inflammatory M2 macrophage phenotype. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors expressed in macrophages where they control the inflammatory response. It has been shown that PPAR{gamma} promotes the differentiation of monocytes into anti-inflammatory M2 macrophages in humans and mice, while a role for PPAR{beta}/{delta} in this process has been reported only in mice and no data are available for PPAR{alpha}. Here, we show that in contrast to PPAR{gamma}, expression of PPAR{alpha} and PPAR{beta}/{delta} overall does not correlate with the expression of M2 markers in human atherosclerotic lesions, whereas a positive correlation with genes of lipid metabolism exists. Moreover, unlike PPAR{gamma}, PPAR{alpha} or PPAR{beta}/{delta} activation does not influence human monocyte differentiation into M2 macrophages in vitro. Thus, PPAR{alpha} and PPAR{beta}/{delta} do not appear to modulate the alternative differentiation of human macrophages.

  14. Identification of the alternative spliced form of the alpha 2/delta subunit of voltage sensitive Ca2+ channels expressed in PC12 cells.

    Science.gov (United States)

    Gilad, B; Shenkar, N; Halevi, S; Trus, M; Atlas, D

    1995-07-07

    The alpha 2/delta subunit of voltage sensitive Ca2+ channels expressed in PC12 has been cloned and partially sequenced. The message observed in Northern blot analysis displays a 7.5 kb transcript, identical in size to mRNA of rabbit skeletal muscle and rat brain. The nucleotide sequence of the cloned alpha 2 subunit of the PC12 specific cDNA is > 99% identical to rat brain sequence and 85% to skeletal muscle. Reverse-transcriptase-polymerase chain reaction (RT-PCR) of the alternative splicing region identifies two deleted regions of 57 bp and 21 bp in PC12 expressed alpha 2/delta transcript. The alternative variant alpha 2e of alpha 2/delta subunit which is expressed in PC12 cells was previously identified in human embryonic kidney (HEK293) cells. RT-PCR analysis show two different sized alternative PCR fragments in rat lung and none in rat spleen, kidney and intestine. Antibodies prepared against a 19 amino acid peptide within the alternative spliced region effectively inhibits [3H]dopamine release in PC12 cells. This implies that the alternatively spliced region is positioned extracellularly and is involved in regulation of the L-type Ca2+ channel-mediated transmitter release.

  15. Theta vocabulary I

    Science.gov (United States)

    Kharchev, S.; Zabrodin, A.

    2015-08-01

    This paper is an annotated list of transformation properties and identities satisfied by the four theta functions θ1, θ2, θ3, θ4 of one complex variable, presented in a ready-to-use form. An attempt is made to reveal a pattern behind various identities for the theta-functions. It is shown that all possible 3, 4 and 5-term identities of degree four emerge as algebraic consequences of the six fundamental bilinear 3-term identities connecting the theta-functions with modular parameters τ and 2 τ.

  16. Precise measurement of $\\sin^22\\theta_{13}$ using Japanese Reactors

    CERN Document Server

    Suekane, F; Araki, T; Jongok, K

    2004-01-01

    After the KamLAND results, the remaining important targets in neutrino experiments are to measure still unknown 3 basic parameters; absolute neutrino mass scale, CP violation phase $\\delta_{CP}$ and last mixing angle $\\theta_{13}$. The angle $\\theta_{13}$ among them is expected to be measured in near future by long baseline accelerator experiments and reactor experiments. In this paper, a realistic idea of high sensitivity reactor measurement of $\\sin^22\\theta_{13}$ is described. This experiment uses a giant nuclear power plant as the neutrino source and three identical detectors are used to cancel detector and neutrino flux uncertainties. The sensitivity reach on $\\sin^22\\theta_{13}$ is $0.017\\sim0.026$ at $\\Delta m^2_{13} \\sim 3 \\times 10^{-3}eV^2$, which is five to seven times better than the current upper limit measured by CHOOZ.

  17. On the Theta semigroup

    OpenAIRE

    Zayed, Ahmed; Urbina, Wilfredo

    2011-01-01

    In this paper we consider a semigroup on trigonometric expansions that will be called the Theta semigroup since its kernel is a multiple of the third Jacobi theta function. We study properties of this semigroup and prove that it is a positive diffusion semigroup. We also obtain that its subordinated semigroup is the classical Poisson semigroup. The extensions to higher dimensions and to periodic ultra distributions are also considered.

  18. The two-loop electroweak bosonic corrections to $\\sin^2\\theta_{\\rm eff}^{\\rm b}$

    CERN Document Server

    Dubovyk, Ievgen; Gluza, Janusz; Riemann, Tord; Usovitsch, Johann

    2016-01-01

    The prediction of the effective electroweak mixing angle $\\sin^2\\theta_{\\rm eff}^{\\rm b}$ in the Standard Model at two-loop accuracy has now been completed by the first calculation of the bosonic two-loop corrections to the $Z{\\bar b}b$ vertex. Numerical predictions are presented in the form of a fitting formula as function of $M_Z, M_W, M_H, m_t$ and $\\Delta{\\alpha}$, ${\\alpha_{\\rm s}}$. For central input values, we obtain a relative correction of $\\Delta\\kappa_{\\rm b}^{(\\alpha^2,\\rm bos)} = -0.9855 \\times 10^{-4}$, amounting to about a quarter of the fermionic corrections, and corresponding to $\\sin^2\\theta_{\\rm eff}^{\\rm b} = 0.232704$. The integration of the corresponding two-loop vertex Feynman integrals with up to three dimensionless parameters in Minkowskian kinematics has been performed with two approaches: (i) Sector decomposition, implemented in the packages FIESTA 3 and SecDec 3, and (ii) Mellin-Barnes representations, implemented in AMBRE 3/MB and the new package MBnumerics.

  19. Sources of alpha-, beta-, gamma-, delta- and epsilon-carotenes: a twentieth century review Fontes de alfa-, beta-, gama-, delta-, e epsilon-carotenos: uma revisão do século XX

    OpenAIRE

    José M. Barbosa-Filho; Adriana A. Alencar; Nunes,Xirley P.; Anna C. de Andrade Tomaz; José G. Sena-Filho; Athayde-Filho, Petrônio F.; Silva, Marcelo S.; Maria F. Vanderlei de Souza; Emidio V. Leitão da-Cunha

    2008-01-01

    Since humans cannot synthesize carotenoids, they depend upon the diet exclusively for the source of these micronutrients. It has claimed that they may alleviate chronic diseases such as cancers. The present communication constitutes a global review of the scientific literature on plants and others organisms that biosynthesize carotenoids, which include the series alpha-, beta-, gamma-, delta- and epsilon-carotenes. The results of the literature survey lists more than five hundred sources.Uma ...

  20. Reductive dechlorination of alpha-, beta-, delta-, and gamma-hexachlorocyclohexane isomers by hydroxocobalamin in the presence of either dithiothreitol or titanium(III) citrate as reducing agents.

    Science.gov (United States)

    Rodríguez-Garrido, B; Arbestain, M Camps; Monterroso, M C; Macías, F

    2004-10-01

    The effect of the reducing potential on the reductive dehalogenation of the different HCH (hexachlorocyclohexane) isomers has not yet been studied. In the present study, the potential for dehalogenation of (alpha-, beta-, delta-, and gamma-HCH isomers by the dithiothreitol (DTT) and titanium(III) citrate (reducing potential at pH 7, -0.33 and -0.48 V, respectively), with and without the addition of hydroxocobalamin was investigated. In the presence of DTT without catalyst, there was no disappearance of any of the HCH isomers studied after 1 h of treatment. However, disappearance of the gamma- and alpha-HCH isomers was observed during the same time period when titanium(III) citrate was used as the reductant in the absence of catalyst (62.9 and 16.6% disappearance, respectively). Addition of the hydroxocobalamin to the DTT system favored mainly the disappearance of gamma- and alpha-HCH (92.9 and 30.8% disappearance after 1 h, respectively); disappearance of delta-HCH and beta-HCH was small (11.9%) or negligible, respectively. Addition of the hydroxocobalamin to the titanium(III) citrate system favored the degradation of all HCH isomers under study: beta- and alpha-HCH completely disappeared to undetectable levels ( alpha-HCH > delta-HCH > beta-HCH, coincided with a decreasing order of the axially positioned Cl atoms of these isomers (considering their thermodynamically most stable configuration). This study is the first description of the rapid degradation of delta- and beta-HCH under abiotic conditions, and the results demonstrate the effect of the reducing potential on the reductive dehalogenation of HCH isomers.

  1. Effects of mental workload and fatigue on the P300, alpha and theta band power during operation of an ERP (P300) brain-computer interface.

    Science.gov (United States)

    Käthner, Ivo; Wriessnegger, Selina C; Müller-Putz, Gernot R; Kübler, Andrea; Halder, Sebastian

    2014-10-01

    The study aimed at revealing electrophysiological indicators of mental workload and fatigue during prolonged usage of a P300 brain-computer interface (BCI). Mental workload was experimentally manipulated with dichotic listening tasks. Medium and high workload conditions alternated. Behavioral measures confirmed that the manipulation of mental workload was successful. Reduced P300 amplitude was found for the high workload condition. Along with lower performance and an increase in the subjective level of fatigue, an increase of power in the alpha band was found for the last as compared to the first run of both conditions. The study confirms that a combination of signals derived from the time and frequency domain of the electroencephalogram is promising for the online detection of workload and fatigue. It also demonstrates that satisfactory accuracies can be achieved by healthy participants with the P300 speller, despite constant distraction and when pursuing the task for a long time.

  2. Mating signals indicating sexual receptiveness induce unique spatio-temporal EEG theta patterns in an anuran species.

    Directory of Open Access Journals (Sweden)

    Guangzhan Fang

    Full Text Available Female mate choice is of importance for individual fitness as well as a determining factor in genetic diversity and speciation. Nevertheless relatively little is known about how females process information acquired from males during mate selection. In the Emei music frog, Babina daunchina, males normally call from hidden burrows and females in the reproductive stage prefer male calls produced from inside burrows compared with ones from outside burrows. The present study evaluated changes in electroencephalogram (EEG power output in four frequency bands induced by male courtship vocalizations on both sides of the telencephalon and mesencephalon in females. The results show that (1 both the values of left hemispheric theta relative power and global lateralization in the theta band are modulated by the sexual attractiveness of the acoustic stimulus in the reproductive stage, suggesting the theta oscillation is closely correlated with processing information associated with mate choice; (2 mean relative power in the beta band is significantly greater in the mesencephalon than the left telencephalon, regardless of reproductive status or the biological significance of signals, indicating it is associated with processing acoustic features and (3 relative power in the delta and alpha bands are not affected by reproductive status or acoustic stimuli. The results imply that EEG power in the theta and beta bands reflect different information processing mechanisms related to vocal recognition and auditory perception in anurans.

  3. Behaviour of {alpha}-, {beta}-, {gamma}-, and {delta}-hexachlorocyclohexane in the soil-plant system of a contaminated site

    Energy Technology Data Exchange (ETDEWEB)

    Calvelo Pereira, R. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, 15782-Santiago de Compostela (Spain)]. E-mail: edrobert@usc.es; Camps-Arbestain, M. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Rodriguez Garrido, B. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Macias, F. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Monterroso, C. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, 15782-Santiago de Compostela (Spain)

    2006-11-15

    The behaviour of the organochlorine pesticide hexachlorocyclohexane (HCH) is investigated. The concentrations of {alpha}-, {beta}-, {gamma}-, and {delta}-HCH isomers were measured in soils, rhizosphere and vegetation in a contaminated area in Galicia (NW Spain). The total concentration of HCH in soils reached values close to 20 000 mg kg{sup -1}. The plants analysed (Avena sativa L., Chenopodium spp., Solanum nigrum L., Cytisus striatus (Hill) Roth, and Vicia sativa L.) accumulated HCH, especially the {beta}-HCH isomer, in their tissues. The most likely mechanisms of HCH accumulation in plants were sorption of soil HCH on roots and sorption of volatilized HCH on aerial plant tissues. The concentrations of HCH obtained from the bulk and rhizosphere soils of selected plant species suggest that roots tend to reduce levels of the HCH isomers in the rhizosphere. The results reflect the importance of vegetation in the distribution of organochlorine compounds in the soil-plant system. - This paper describes the soil-plant relationship of hexachlorocyclohexane isomers in a contaminated site, with special focus on the rhizosphere effect.

  4. 15-Deoxy-Delta(12,14)-prostaglandin-J(2) reveals a new pVHL-independent, lysosomal-dependent mechanism of HIF-1alpha degradation.

    Science.gov (United States)

    Olmos, Gemma; Arenas, María I; Bienes, Raquel; Calzada, María Jose; Aragonés, Julián; Garcia-Bermejo, Maria Laura; Landazuri, Manuel O; Lucio-Cazaña, Javier

    2009-07-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) protein is degraded under normoxia by its association to von Hippel-Lindau protein (pVHL) and further proteasomal digestion. However, human renal cells HK-2 treated with 15-deoxy-Delta(12,14)-prostaglandin-J(2) (15d-PGJ(2)) accumulate HIF-1alpha in normoxic conditions. Thus, we aimed to investigate the mechanism involved in this accumulation. We found that 15d-PGJ(2) induced an over-accumulation of HIF-1alpha in RCC4 cells, which lack pVHL and in HK-2 cells treated with inhibitors of the pVHL-proteasome pathway. These results indicated that pVHL-proteasome-independent mechanisms are involved, and therefore we aimed to ascertain them. We have identified a new lysosomal-dependent mechanism of HIF-1alpha degradation as a target for 15d-PGJ(2) based on: (1) HIF-1alpha colocalized with the specific lysosomal marker Lamp-2a, (2) 15d-PGJ(2) inhibited the activity of cathepsin B, a lysosomal protease, and (3) inhibition of lysosomal activity did not result in over-accumulation of HIF-1alpha in 15d-PGJ(2)-treated cells. Therefore, expression of HIF-1alpha is also modulated by lysosomal degradation.

  5. Emerging Magnetism Arising from Self-Damage in (alpha) and (delta)-Pu

    Energy Technology Data Exchange (ETDEWEB)

    McCall, S K; Fluss, M J; Chung, B W; Chapline, G F; Jackson, D D; McElfresh, M W

    2005-11-16

    As a consequence of the unusual nature of plutonium's electronic structure, point- and extended-defects are expected to, and do exhibit extraordinary properties[1]. Low temperature magnetic susceptibility measurements on Pu and fcc-Pu(Ga) show that the magnetic susceptibility increases as a function of time, yet upon annealing the specimen returns to its initial magnetic susceptibility. This excess magnetic susceptibility (EMS) arises from the {alpha}-decay and U recoil damage cascades which produce vacancy and interstitials as point and extended defects. The temperature of the first annealing stage defines a temperature (<35K) below which we are able to characterize the time and temperature evolution of the accumulating damage cascades as being a saturation function. The temperature dependence of the EMS is well described by a time independent, Curie-Weiss curve arising from a volumetric region surrounding each U damage cascade. This saturation picture also leads directly to a determination of the microscopic volume of the specimen that is affected by the frozen-in damage cascade. For our measurements in d-Pu we calculate a diameter of the magnetically affected volume of {approx} 250 {angstrom} per damage cascade. This should be compared with an estimated volume that encloses the damage cascade itself (determined from molecular dynamics) of {approx}100 {angstrom}. Hence, the ratio of these volumes is {approx}8. The observed anomalous magnetic behavior is likely a consequence of the highly correlated nature of the electrons. Similarities with defects in hole-doped superconductors suggest a general phenomenon in strongly correlated electron systems, of which Pu may be a particularly unusual or special example.

  6. Performance comparison of two Olympus InnovX handheld x-ray analyzers for feasibility of measuring arsenic in skin in vivo - Alpha and Delta models.

    Science.gov (United States)

    Desouza, E D; Gherase, M R; Fleming, D E B; Chettle, D R; O'Meara, J M; McNeill, F E

    2017-05-01

    The Figure-Of-Merit (FOM) performance, a combination of detection limit and dose, is compared between two generations of handheld X-Ray Fluorescence (XRF) spectrometers for the feasibility of in vivo XRF measurement of arsenic (As) in skin. The Olympus InnovX Delta model analyzer (40 kVp using either 37 or 17μA) was found to show improvements in Minimum Detection Limit (MDL) using arsenic As-doped skin calibration phantoms with bulk tissue backing, when compared to the first generation InnovX Alpha model (40kVp, 20μA) in 120s measurements. Differences between two different definitions of MDL are discussed. On the Delta system, an MDL of (0.462±0.002) μg/g As was found in phantoms, with a nylon backing behind to mimic bulk tissue behind skin. The equivalent and effective doses were found to be (10±2) mSv and ~7×10(-3)μSv respectively for the Alpha and (15±4) mSv and ~8×10(-3)μSv respectively for the Delta system in 120s exposures. Combining MDL and effective dose, a lower (better) FOM was found for the Delta, (1.7±0.4) ppm mSv(1/2), compared to (4.4±0.5) ppm mSv(1/2) for the Alpha model system. The Delta analyzer demonstrates improved overall system performance for a rapid 2-min measurement in As skin phantoms, such that it can be considered for use in populations exposed to arsenic.

  7. Design of peptides with alpha,beta-dehydro residues: pseudo-tripeptide N-benzyloxycarbonyl-DeltaLeu-L-Ala-L-Leu-OCH3.

    Science.gov (United States)

    Makker, Jyoti; Dey, Sharmistha; Kumar, Pravindra; Singh, Tej P

    2002-04-01

    The title peptide N-benzyloxycarbonyl-DeltaLeu-L-Ala-L-Leu-OCH(3) [methyl N-(benzyloxycarbonyl)-alpha,beta-dehydroleucyl-L-alanyl-L-leucinate], C(24)H(35)N(3)O(6), was synthesized in the solution phase. The peptide adopts a type II' beta-turn conformation which is stabilized by an intramolecular 4 --> 1 N-H* * *O hydrogen bond. The crystal packing is stabilized by two intermolecular N-H* * *O hydrogen bonds.

  8. Quantitative EEG in Children and Adults With Attention Deficit Hyperactivity Disorder: Comparison of Absolute and Relative Power Spectra and Theta/Beta Ratio.

    Science.gov (United States)

    Markovska-Simoska, Silvana; Pop-Jordanova, Nada

    2017-01-01

    In recent decades, resting state electroencephalographic (EEG) measures have been widely used to document underlying neurophysiological dysfunction in attention deficit hyperactivity disorder (ADHD). Although most EEG studies focus on children, there is a growing interest in adults with ADHD too. The aim of this study was to objectively assess and compare the absolute and relative EEG power as well as the theta/beta ratio in children and adults with ADHD. The evaluated sample comprised 30 male children and 30 male adults with ADHD diagnosed according to DSM-IV criteria. They were compared with 30 boys and 30 male adults matched by age. The mean age (±SD) of the children's group was 9 (±2.44) years and the adult group 35.8 (±8.65) years. EEG was recorded during an eyes-open condition. Spectral analysis of absolute (μV(2)) and relative power (%) was carried out for 4 frequency bands: delta (2-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-21 Hz). The findings obtained for ADHD children are increased absolute power of slow waves (theta and delta), whereas adults exhibited no differences compared with normal subjects. For the relative power spectra there were no differences between the ADHD and control groups. Across groups, the children showed greater relative power than the adults in the delta and theta bands, but for the higher frequency bands (alpha and beta) the adults showed more relative power than children. Only ADHD children showed greater theta/beta ratio compared to the normal group. Classification analysis showed that ADHD children could be differentiated from the control group by the absolute theta values and theta/beta ratio at Cz, but this was not the case with ADHD adults. The question that should be further explored is if these differences are mainly due to maturation processes or if there is a core difference in cortical arousal between ADHD children and adults. © EEG and Clinical Neuroscience Society (ECNS) 2016.

  9. Exposure assessment to alpha- and beta-pinene, delta(3)-carene and wood dust in industrial production of wood pellets.

    Science.gov (United States)

    Edman, K; Lofstedt, H; Berg, P; Eriksson, K; Axelsson, S; Bryngelsson, I; Fedeli, C

    2003-04-01

    The main aim of the study was to measure the exposure to monoterpenes (alpha- and beta-pinene and Delta(3)-carene) and wood dust during industrial production of wood pellets and briquettes. Additional aims were to compare the results from wood dust sampled on a filter with real time measurements using a direct reading instrument and to identify peak exposures to dust. Twenty-four men working at six companies involved in industrial production of wood pellets and briquettes participated in the study. Monoterpenes were measured by diffusive sampling and wood dust was measured as total dust. A data logger (DataRAM) was used for continuous monitoring of dust concentration for 18 of the participants. The sampling time was approximately 8 h. The personal exposure to monoterpenes ranged from 0.64 to 28 mg/m(3) and a statistically significant (Kruskal-Wallis test, P = 0.0002) difference in levels of monoterpenes for workers at different companies was seen. In the companies the personal exposure to wood dust varied between 0.16 and 19 mg/m(3) and for 10 participants the levels exceeded the present Swedish occupational exposure limit (OEL) of 2 mg/m(3). The levels of wood dust during the morning shift were significantly (Mann-Whitney test, P = 0.04) higher compared with the afternoon shift. Continuous registration of dust concentration showed peak values for several working operations, especially cleaning of truck engines with compressed air. For 24 workers in six companies involved in industrial production of wood pellets the personal exposure to monoterpenes was low and to wood dust high compared with the present Swedish OEL and previous studies in Swedish wood industries. Since the DataRAM can identify critical working tasks with high wood dust exposure a reduction in exposure levels could probably be achieved by changes in working routines and by the use of protective equipment.

  10. Archaeal translation initiation revisited: the initiation factor 2 and eukaryotic initiation factor 2B alpha-beta-delta subunit families

    Science.gov (United States)

    Kyrpides, N. C.; Woese, C. R.

    1998-01-01

    As the amount of available sequence data increases, it becomes apparent that our understanding of translation initiation is far from comprehensive and that prior conclusions concerning the origin of the process are wrong. Contrary to earlier conclusions, key elements of translation initiation originated at the Universal Ancestor stage, for homologous counterparts exist in all three primary taxa. Herein, we explore the evolutionary relationships among the components of bacterial initiation factor 2 (IF-2) and eukaryotic IF-2 (eIF-2)/eIF-2B, i.e., the initiation factors involved in introducing the initiator tRNA into the translation mechanism and performing the first step in the peptide chain elongation cycle. All Archaea appear to posses a fully functional eIF-2 molecule, but they lack the associated GTP recycling function, eIF-2B (a five-subunit molecule). Yet, the Archaea do posses members of the gene family defined by the (related) eIF-2B subunits alpha, beta, and delta, although these are not specifically related to any of the three eukaryotic subunits. Additional members of this family also occur in some (but by no means all) Bacteria and even in some eukaryotes. The functional significance of the other members of this family is unclear and requires experimental resolution. Similarly, the occurrence of bacterial IF-2-like molecules in all Archaea and in some eukaryotes further complicates the picture of translation initiation. Overall, these data lend further support to the suggestion that the rudiments of translation initiation were present at the Universal Ancestor stage.

  11. Ti-N films created in close vicinity of transition from. alpha. -Ti(N) to. delta. -TiN sub x phase

    Energy Technology Data Exchange (ETDEWEB)

    Poulek, V.; Musil, J. (Inst. of Physics, Czechoslovak Academy of Sciences, Prague (Czechoslovakia)); Valvoda, V.; Dobiasova, L. (Charles Univ., Prague (Czechoslovakia))

    1991-07-07

    Ti-N films with nitrogen content ranging from 20 to 40 at.% are multiphase films which can contain {alpha}-Ti(N)+{delta}-TiN{sub x}, {alpha}-Ti(N)+{epsilon}-Ti{sub 2}N or {alpha}-Ti(N)+{epsilon}-Ti{sub 2}N+{delta}-TiN{sub x} phases. Mixed phase films exhibit some extraordinary properties in comparison with single-phase films. It was found that growth of the {epsilon}-Ti{sub 2}N phase is very sensitive to changes of some deposition parameters, especially the substrate surface temperature T{sub s}, the substrate ion current density i{sub s}, the ion energy E{sub i} and the deposition rate a{sub D}. The growth can be controlled not only by the substrate temperature T{sub s} under equilibrium conditions but also by the energy density S{sub E}=i{sub s}E{sub i}/a{sub D} delivered to the growing film. Special attention is devoted to films produced at surface temperatures T{sub s} lower than that necessary for the production of films containing the {epsilon}-Ti{sub 2}N phase. These films have a milky appearance and exhibit ''large'' (1-5 {mu}m) hexagonal {alpha}-Ti(N) crystallites. Conditions under which these films can be prepared are discussed in detail. (orig.).

  12. Transient Global Amnesia Deteriorates the Network Efficiency of the Theta Band

    Science.gov (United States)

    Yi, SangHak; Lim, Jae-Sung; Jang, Jae-Won; Im, Chang-Hwan; Kim, SangYun

    2016-01-01

    Acute perturbation of the hippocampus, one of the connector hubs in the brain, is a key step in the pathophysiological cascade of transient global amnesia (TGA). We tested the hypothesis that network efficiency, meaning the efficiency of information exchange over a network, is impaired during the acute stage of TGA. Graph theoretical analysis was applied to resting-state EEG data collected from 21 patients with TGA. The EEG data were obtained twice, once during the acute stage ( 2 months after symptom onset) of TGA. Characteristic path lengths and clustering coefficients of functional networks constructed using phase-locking values were computed and normalized as a function of the degree in the delta, theta, alpha, beta 1, beta 2 and gamma frequency bands of the EEG. We investigated whether the normalized characteristic path length (nCPL) and normalized clustering coefficients (nCC) differed significantly between the acute and resolved stages of TGA at each frequency band using the Wilcoxon signed-rank test. For networks where the nCPL or nCC differed significantly between the two stages, we also evaluated changes in the connections of the brain networks. During the acute stage of TGA, the nCPL of the theta band networks with mean degrees of 8, 8.5, 9 and 9.5 significantly increased (P < 0.05). During the acute stage, the lost edges for these networks were mostly found between the anterior (frontal and anterior temporal) and posterior (parieto-occipital and posterior temporal) brain regions, whereas newly developed edges were primarily found between the left and right frontotemporal regions. The nCC of the theta band with a mean degree of 5.5 significantly decreased during the acute stage (P < 0.05). Our results indicate that TGA deteriorates the network efficiency of the theta frequency band. This effect might be related to the desynchronization between the anterior and posterior brain areas. PMID:27741293

  13. Description of two new alpha variants: Hb Canuts [alpha85(F6)Asp-->His (alpha1)] and Hb Ambroise Pare [alpha117(GH5)Phe-->Ile (alpha2)]; two new beta variants: Hb Beaujolais [beta84(EF8)Thr-->Asn] and Hb Monplaisir [beta147 (Tyr-Lys-Leu-Ala-Phe-Phe-Leu-Leu-Ser-Asn-Phe-Tyr-158-COOH)] and one new delta variant: Hb (A2)North Africa [delta59(E3)Lys-->Met].

    Science.gov (United States)

    Joly, Philippe; Lacan, Philippe; Bererd, Martine; Garcia, Caroline; Zanella-Cleon, Isabelle; Becchi, Michel; Aubry, Martine; Couprie, Nicole; Francina, Alain

    2009-01-01

    We present here five new hemoglobin (Hb) variants which have been identified during routine Hb analysis before their genotypic characterization. Four of these result from a classical missense mutation: Hb Canuts [alpha85(F6)Asp-->His (alpha1)], Hb Ambroise Pare [alpha117(GH5)Phe-->Ile (alpha2)], Hb Beaujolais [beta84(EF8)Thr-->Asn] and HbA(2)-North Africa [delta59(E3)Lys-->Met]. The last one, Hb Monplaisir [beta147 (Tyr-Lys-Leu-Ala-Phe-Phe-Leu-Leu-Ser-Asn-Phe-Tyr-158-COOH)], results from a frameshift mutation at the stop codon of the beta-globin gene which leads to a modified C-terminal sequence in the beta-globin chain. None of these variants seem to have a particular clinical expression in the heterozygous state. The circumstances of the discovery of these five new Hb variants emphasize the fact that an association of techniques is necessary for a complete screening of Hb variants during routine Hb analysis. Globin chain separation by reversed phase liquid chromatography (RP-LC) appears to be the most relevant method.

  14. What is $\\Delta m^2_{ee}$ ?

    CERN Document Server

    Parke, Stephen

    2016-01-01

    The current short baseline reactor experiments, Daya Bay and RENO (Double Chooz) have measured (or are capable of measuring) an effective $\\Delta m^2$ associated with the atmospheric oscillation scale of 0.5 km/MeV in electron anti-neutrino disappearance. In this paper, I compare and contrast the different definitions of such an effective $\\Delta m^2$ and argue that the simple, L/E independent, definition given by $\\Delta m^2_{ee} \\equiv \\cos^2 \\theta_{12} \\Delta m^2_{31}+ \\sin^2 \\theta_{12} \\Delta m^2_{32}$, i.e. "the $\

  15. Comprehensive alpha, beta and delta cell transcriptomes reveal that ghrelin selectively activates delta cells and promotes somatostatin release from pancreatic islets

    Directory of Open Access Journals (Sweden)

    Michael R. DiGruccio

    2016-07-01

    Conclusions: These results offer a straightforward explanation for the well-known insulinostatic actions of ghrelin. Rather than engaging beta cells directly, ghrelin engages delta cells to promote local inhibitory feedback that attenuates insulin release. These findings illustrate the power of our approach to resolve some of the long-standing conundrums with regard to the rich feedback that occurs within the islet that is integral to islet physiology and therefore highly relevant to diabetes.

  16. What triggers $\\theta_{13}$ discrepancy between Daya Bay and T2K?

    CERN Document Server

    Haba, Naoyuki; Shimada, Kyousuke; Yamaguchi, Yuya

    2015-01-01

    There seems to be a non-negligible discrepancy between Daya Bay and T2K experimental results of a neutrino mixing angle, $\\theta_{13}$ . We show the discrepancy can be simply passed away even in the standard three neutrinos framework by taking the same value of $\\Delta m^2_{32}$ with a normal neutrino mass hierarchy and Dirac CP phase $\\delta = -\\pi/ 2$, which is favorable in T2K experiment. For numerical analyses of neutrino oscillation probabilities, there are five independent parameters, $\\Delta m_{21}^2$, $\\Delta m_{32}^2$, $\\theta_{12}$, $\\theta_{23}$, and $\\delta$. We reevaluate $\\theta_{13}$ by scatter plots within $1 \\sigma$ range of five-dimensional parameters space suggested by PDG, T2K, and Daya Bay. We project onto $\\delta$-$\\sin^2 2 \\theta_{13}$ plane and find an overlap area of $\\theta_{13}$ suggested by T2K and Daya Bay. In the normal hierarchy case, the largest overlap area is given by parameters set suggested by T2K, and the overlap area becomes small in order of parameters sets suggested by ...

  17. The Two-Loop Anomalous Dimension Matrix for $\\Delta S=1$ Weak Non-Leptonic Decays; 1, ${\\cal O}(\\alpha_s^2)$

    CERN Document Server

    Buras, Andrzej J; Lautenbacher, M E; Weisz, P; Buras, Andrzej J.; Jamin, Matthias; Lautenbacher, Markus E.; Weisz, Peter H.

    1993-01-01

    We calculate the two-loop $10 \\times 10$ anomalous dimension matrix ${\\cal O}(\\alpha_s^{2})$ involving current-current operators, QCD penguin operators, and electroweak penguin operators especially relevant for $\\Delta S=1$ weak non-leptonic decays, but also important for $\\Delta B=1$ decays. The calculation is performed in two schemes for $\\gamma_{5}$: the dimensional regularization scheme with anticommuting $\\gamma_{5}$ (NDR), and in the 't Hooft-Veltman scheme. We demonstrate how a direct calculation of diagrams involving $\\gamma_{5}$ in closed fermion loops can be avoided thus allowing a consistent calculation in the NDR scheme. The compatibility of the results obtained in the two schemes considered is verified and the properties of the resulting matrices are discussed. The two-loop corrections are found to be substantial. The two-loop anomalous dimension matrix ${\\cal O}(\\alpha_e\\alpha_s)$, required for a consistent inclusion of electroweak penguin operators, is presented in a subsequent publication.

  18. Transcriptomic profiling of pancreatic alpha, beta and delta cell populations identifies delta cells as a principal target for ghrelin in mouse islets

    DEFF Research Database (Denmark)

    Adriaenssens, Alice E; Svendsen, Berit; Lam, Brian Y H

    2016-01-01

    AIMS/HYPOTHESIS: Intra-islet and gut-islet crosstalk are critical in orchestrating basal and postprandial metabolism. The aim of this study was to identify regulatory proteins and receptors underlying somatostatin secretion though the use of transcriptomic comparison of purified murine alpha, bet...

  19. The production of alpha/beta and gamma/delta double negative (DN) T-cells and their role in the maintenance of pregnancy.

    Science.gov (United States)

    Chapman, John C; Chapman, Fae M; Michael, Sandra D

    2015-07-12

    The ability of the thymus gland to convert bone marrow-derived progenitor cells into single positive (SP) T-cells is well known. In this review we present evidence that the thymus, in addition to producing SP T-cells, also has a pathway for the production of double negative (DN) T-cells. The existence of this pathway was noted during our examination of relevant literature to determine the cause of sex steroid-induced thymocyte loss. In conducting this search our objective was to answer the question of whether thymocyte loss is the end product of a typical interaction between the reproductive and immune systems, or evidence that the two systems are incompatible. We can now report that "thymocyte loss" is a normal process that occurs during the production of DN T-cells. The DN T-cell pathway is unique in that it is mediated by thymic mast cells, and becomes functional following puberty. Sex steroids initiate the development of the pathway by binding to an estrogen receptor alpha located in the outer membrane of the mast cells, causing their activation. This results in their uptake of extracellular calcium, and the production and subsequent release of histamine and serotonin. Lymphatic vessels, located in the subcapsular region of the thymus, respond to the two vasodilators by undergoing a substantial and preferential uptake of gamma/delta and alpha/beta DN T- cells. These T- cells exit the thymus via efferent lymphatic vessels and enter the lymphatic system.The DN pathway is responsible for the production of three subsets of gamma/delta DN T-cells and one subset of alpha/beta DN T-cells. In postpubertal animals approximately 35 % of total thymocytes exit the thymus as DN T-cells, regardless of sex. In pregnant females, their levels undergo a dramatic increase. Gamma/delta DN T-cells produce cytokines that are essential for the maintenance of pregnancy.

  20. Taxonomy Icon Data: Guillardia theta [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Guillardia theta Guillardia theta Guillardia_theta_L.png Guillardia_theta_NL.png Guillardia_the...ta_S.png Guillardia_theta_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Guillardia+the...ta&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Guillardia+theta&t=NL http://biosciencedbc.jp/taxono...my_icon/icon.cgi?i=Guillardia+theta&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Guillardia+the

  1. Relationship of changing delta 4-steroid 5 alpha-reductase activity to (125I)iododeoxyuridine uptake during regeneration of involuted rat prostates

    Energy Technology Data Exchange (ETDEWEB)

    Kitahara, S.; Higashi, Y.; Takeuchi, S.; Oshima, H. (Tokyo Medical and Dental Univ. (Japan))

    1989-04-01

    To elucidate the phenotypic expression of proliferating prostatic cells, rats were castrated, and the regenerating process of involuted ventral prostates during testosterone propionate (TP) administration was investigated by examining morphology, (5-{sup 125}I)iododeoxyuridine ({sup 125}I-UdR) uptake, DNA content, weight, acid phosphatase, and delta 4-steroid 5 alpha-reductase (5 alpha-reductase) activities. Morphologically, TP treatment initially increased the number of epithelial cells lining glandular lobules and subsequently restored the shape of epithelial cells. {sup 125}I-UdR uptake peaked on Day 3 of TP treatment and stayed at higher levels than for uncastrated controls until Day 14 of treatment. Prostatic weight, protein content, acid phosphatase, and DNA content returned to uncastrated control levels by Day 14 of TP treatment. TP administration markedly stimulated prostatic 5 alpha-reductase activity, which peaked on the Day 5 of treatment and decreased to uncastrated control levels by Day 14 of treatment. It is concluded that TP administration to castrated rats initially induced active mitotic division of the remaining stem cells, followed by formation of differentiated functional epithelial cells. Prostatic 5 alpha-reductase was highly active at the initial phase of active mitotic cell division. The major portion of the increased enzyme activity can be regarded as a phenotypic expression of stem or transient cells of prostatic epithelium.

  2. Increased tumor necrosis factor-alpha and nitric oxide production by rat macrophages following in vitro stimulation and intravenous administration of the delta-opioid agonist SNC 80.

    Science.gov (United States)

    Gomez-Flores, R; Rice, K C; Zhang, X; Weber, R J

    2001-05-04

    Opioids alter immune function by binding to opioid receptors on cells of the immune system, or indirectly by acting on receptors within the central nervous system. Mu-selective opioid agonists are generally associated with immunosuppression, whereas delta-opioid receptor-selective agonists are commonly associated with immunopotentiation. We have previously shown that intracerebroventricular administration of the nonpeptide delta-opioid receptor agonist (+)-4-((alpha R)-alpha-((2S, 5R)-4-allyl-2, 5-dimethyl-1-piperazinyl)-3-methoxybenzyl)-N, N-diethyl-benzamide (SNC 80) did not alter certain parameters of immunocompetence. In the present study, we studied the in vitro and ex vivo effects of SNC 80 on rat macrophage and lymphocyte functions. We showed that SNC 80 at concentrations of 10(-7) M and 10(-6) M, significantly (P SNC 80 (6.8 mg/kg) significantly (P SNC 80 plus Con A potentiated ex vivo LPS-stimulated macrophage functions. SNC 80 could potentially be utilized in various clinical situations where immunosuppression is undesirable.

  3. Medical image of the week: alpha intrusion into REM sleep

    Directory of Open Access Journals (Sweden)

    Shetty S

    2015-12-01

    Full Text Available A 45-year-old woman with a past medical history of hypertension and chronic headaches was referred to the sleep laboratory for high clinical suspicion for sleep apnea based on a history of snoring, witnessed apnea and excessive daytime sleepiness. An overnight sleep study was performed. Images during N3 Sleep and REM sleep are shown (Figures 1 and 2. Alpha intrusion in delta sleep is seen in patients with fibromyalgia, depression, chronic fatigue syndrome, anxiety disorder, and primary sleep disorders like psychophysiological insomnia, obstructive sleep apnea, circadian disorders and narcolepsy (1. Bursts of alpha waves during REM sleep may be more common during phasic REM than tonic REM. The REM alpha bursts (alpha activity lasting at least 3 seconds without an increase in EMG amplitude may represent microarousals (2. Hypersynchronous theta activity should be differentiated from the spike and waveform activity seen in seizures.

  4. Justifying the exotic Theta+ pentaquark

    CERN Document Server

    Diakonov, Dmitri

    2009-01-01

    The existence of a light S=+1 baryon resonance follows from Quantum Field Theory applied to baryons. This is illustrated in the Skyrme model (where Theta+ exists but is too strong) and in a new mean field approach where Theta+ arises as a consequence of three known resonances: Lambda(1405), N(1440) and N(1535).

  5. Theta vocabulary II. Multidimensional case

    CERN Document Server

    Kharchev, S

    2015-01-01

    It is shown that the Jacobi and Riemann identities of degree four for the multidimensional theta functions as well as the Weierstrass identities emerge as algebraic consequences of the fundamental multidimensional binary identities connecting the theta functions with Riemann matrices $\\tau$ and $2\\tau$.

  6. Theta vocabulary II. Multidimensional case

    Science.gov (United States)

    Kharchev, S.; Zabrodin, A.

    2016-06-01

    It is shown that the Jacobi and Riemann identities of degree four for the multidimensional theta functions as well as the Weierstrass identities emerge as algebraic consequences of the fundamental multidimensional binary identities connecting the theta functions with Riemann matrices τ and 2 τ.

  7. Sources of alpha-, beta-, gamma-, delta- and epsilon-carotenes: a twentieth century review Fontes de alfa-, beta-, gama-, delta-, e epsilon-carotenos: uma revisão do século XX

    Directory of Open Access Journals (Sweden)

    José M. Barbosa-Filho

    2008-03-01

    Full Text Available Since humans cannot synthesize carotenoids, they depend upon the diet exclusively for the source of these micronutrients. It has claimed that they may alleviate chronic diseases such as cancers. The present communication constitutes a global review of the scientific literature on plants and others organisms that biosynthesize carotenoids, which include the series alpha-, beta-, gamma-, delta- and epsilon-carotenes. The results of the literature survey lists more than five hundred sources.Uma vez que os humanos não podem sintetizar carotenóides, dependem exclusivamente da dieta como fonte desses micronutrientes. Tem sido afirmado que eles podem aliviar doenças crônicas, tais como cânceres. O presente artigo constitui uma revisão global da literatura científica sobre plantas e outros organismos que biossintetizam carotenóides, que incluem as séries alfa-, beta-, gama-, delta-, e epsilon-carotenos. Os resultados das listas de pesquisa da literatura mostram mais de quinhentas fontes.

  8. A genome-wide linkage scan of theta band activity as an endophenotype for schizophrenia

    NARCIS (Netherlands)

    Aukes, Maartje F.; Boks, Marco P.M.; Willems, Anne E.; Van Lutterveld, Remko; Sommer, Iris E.; Sitskoorn, Margriet M.; Ophoff, Roel A.; Alizadeh, Behrooz Z.; Kahn, Rene S.

    Background: Deviant brain oscillations are candidate endophenotypes for schizophrenia. Our aim was to find new quantitative trait loci for brain oscillations and putatively schizophrenia. Methods: We systematically investigated the genetic characteristics of theta, alpha, and beta oscillations at

  9. Theta functions and mirror symmetry

    CERN Document Server

    Gross, Mark

    2012-01-01

    This is a survey covering aspects of varied work of the authors with Mohammed Abouzaid, Paul Hacking, and Sean Keel. While theta functions are traditionally canonical sections of ample line bundles on abelian varieties, we motivate, using mirror symmetry, the idea that theta functions exist in much greater generality. This suggestion originates with the work of the late Andrei Tyurin. We outline how to construct theta functions on the degenerations of varieties constructed in previous work of the authors, and then explain applications of this construction to homological mirror symmetry and constructions of broad classes of mirror varieties.

  10. Frontal theta activity reflects distinct aspects of mental fatigue.

    Science.gov (United States)

    Wascher, Edmund; Rasch, Björn; Sänger, Jessica; Hoffmann, Sven; Schneider, Daniel; Rinkenauer, Gerhard; Heuer, Herbert; Gutberlet, Ingmar

    2014-02-01

    Longer lasting performance in cognitively demanding tasks leads to an exhaustion of cognitive resources and to a state commonly described as mental fatigue. More specifically, the allocation and focusing of attention become less efficient with time on task. Additionally, the selection of even simple responses becomes more error prone. With respect to the recorded EEG, mental fatigue has been reported to be associated with an increase in frontal theta and frontal and occipital alpha activity. The present study focused on the time course of changes in behavior and in the EEG to characterize fatigue-related processes. Participants performed a spatial stimulus-response-compatibility task in eight blocks for an overall duration of 4h. Error rates increased continuously with time on task. Total alpha power was larger at the end compared to the beginning of the experiment. However, alpha power increased rapidly and reached its maximal amplitude already after 1h, whereas frontal theta showed a continuous increase with time on task, possibly related to increased effort to keep the performance level high. Time frequency analyses revealed power changes in the theta band induced by task relevant information that might be assigned to a drain of executive control capacities. Thus, frontal theta turned out to be a reliable marker of distinct changes in cognitive processing with increasing fatigue.

  11. Dexamphetamine reduces auditory P3 delta power and phase-locking while increasing gamma power.

    Science.gov (United States)

    Albrecht, Matthew A; Price, Greg; Lee, Joseph; Iyyalol, Rajan; Martin-Iverson, Mathew T

    2012-10-01

    Auditory P3 amplitude reduction is one of the most robust and replicated findings in schizophrenia. Recent evidence suggests that these reductions are due to reductions in both power and phase-locking at delta and theta frequencies. We have previously shown that the auditory, but not visual, P3 is reduced in healthy participants given the catecholamine releasing agent dexamphetamine. Our aim was to determine whether the auditory P3 amplitude reduction induced by dexamphetamine has similar power and phase locking characteristics to that seen in schizophrenia. Forty-four healthy participants were given 0.45 mg/kg dexamphetamine and placebo, in a double-blinded, placebo-controlled, cross-over design. The task was a three-stimulus auditory odd-ball task, target stimuli were the major stimuli of interest. Individual target trials underwent wavelet analysis to give power and phase-locking of delta (3 Hz), theta (4-7 Hz), alpha (8-12 Hz), beta (13-30 Hz) and gamma (30-50 Hz) frequencies for a 50 ms time window centred around the peak of the target P3. Delta power around the P3 peak was significantly reduced when participants were given dexamphetamine. Delta phase-locking was also reduced but only when analysis was targeted at the location of the peak P3 amplitude. In contrast, theta power and phase-locking were not affected by dexamphetamine. These findings suggest that increased catecholamine activity may be responsible for the power and phase-locking reductions of the auditory P3 delta component in patients with schizophrenia. Interestingly, dexamphetamine significantly increased gamma power around the P3 peak. We attempt to link this finding with the gamma alterations that have been found in patients with schizophrenia.

  12. Nicotine induction of theta frequency oscillations in rodent hippocampus in vitro.

    Science.gov (United States)

    Lu, C B; Henderson, Z

    2010-03-10

    The hippocampus is an area important for learning and memory and exhibits prominent and behaviourally relevant theta (4-12 Hz) and gamma (30-100 Hz) frequency oscillations in vivo. Hippocampal slices produce similar types of oscillatory activity in response to bath-application of neurotransmitter receptor agonists. The medial septum diagonal band area (MS/DB) provides both a cholinergic and GABAergic projection to the hippocampus, and although it plays a major role in the generation and maintenance of the hippocampal theta rhythm in vivo, there is evidence for intrinsic theta generation mechanisms in the hippocampus, especially in area CA3. The aim of this study was to examine the role of the nicotinic receptor (nAChR) in the induction of oscillatory field activity in the in vitro preparation of the rat hippocampus. Bath-application of a low concentration of nicotine (1 muM) to transversely-cut hippocampal slices produced persistent theta-frequency oscillations in area CA3 of the hippocampus. These oscillations were reduced by both GABA(A) receptor antagonists and ionotropic glutamate receptor antagonists, indicating the involvement of local GABAergic and glutamatergic neurons in the production of the rhythmic theta activity. The nicotine-induced theta activity was inhibited by non-selective nAChR antagonists and partially by an alpha7* nAChR antagonist. The induction of theta frequency oscillations in CA3 by nicotine was mimicked alpha7* nAChR agonists but not by non-alpha7* nAChR agonists. In conclusion, theta activity in the hippocampus may be promoted by tonic stimulation of alpha7* nAChRs, possibly via selective stimulation of theta-preferring interneurons in the hippocampus that express post-synaptic alpha7* nAChRs.

  13. The alpha, beta, gamma, delta-unsaturated aldehyde 2-trans-4-trans-decadienal disturbs DNA replication and mitotic events in early sea urchin embryos.

    Science.gov (United States)

    Hansen, Espen; Even, Yasmine; Genevière, Anne-Marie

    2004-09-01

    The polyunsaturated aldehydes are highly reactive products of fatty acid peroxidation and combustion of organic materials, and they have been documented to have diverse cyctotoxic and genotoxic effects. The alpha,beta,gamma,delta-unsaturated aldehyde 2-trans-4-trans-decadienal is produced by marine microalgae, and it is known to inhibit cell proliferation and induce apoptosis in several different cell types. However, the molecular basis for the cell cycle arrest is not fully understood. We used sea urchin embryos to examine how some of the key events of the mitotic cell division were influenced by this polyunsaturated aldehyde. We found that cell divisions in embryos of Sphaerechinus granularis were inhibited by 2-trans-4-trans-decadienal in a dose dependent manner with an EC50 of 1.3 microM. Mitotic events in the nondividing eggs were characterized using immunofluorescent staining. DNA labelling revealed that pronuclear migration was inhibited, and a total absence of incorporation of the DNA-base analogue 5-bromo-2-deoxyuridine indicated that no DNA replication had occurred. Staining of alpha-tubulin subunits showed that tubulin-polymerization was disrupted and aberrations were induced in mitotic spindles. Furthermore, we monitored the activity of the G2-M promoting complex cyclin B-Cdk1 in newly fertilized sea urchin eggs, and found that this complex was not activated in embryos treated with 2-trans-4-trans-decadienal despite the accumulation of cyclin B.

  14. The Daya Bay and T2K results on $\\sin^2 2 \\theta_{13}$ and Non-Standard Neutrino Interactions

    CERN Document Server

    Girardi, I; Petcov, S T

    2014-01-01

    We show that the relatively large best fit value of $\\sin^2 2 \\theta_{13} = 0.14 \\, (0.17)$ measured in the T2K experiment for fixed values of i) the Dirac CP violation phase $\\delta = 0$, and ii) the atmospheric neutrino mixing parameters $\\theta_{23} = \\pi/4$, $|\\Delta m^2_{32}| = 2.4 \\times 10^{-3} \\; {\\rm eV}^2$, can be reconciled with the Daya Bay result $\\sin^2 2 \\theta_{13} = 0.090 \\pm 0.009$ if the effects of non-standard neutrino interactions (NSI) in the relevant $\\bar \

  15. Statistical convergence of order $\\alpha$ in probability

    OpenAIRE

    Pratulananda Das; Sanjoy Ghosal; Sumit Som

    2016-01-01

    In this paper ideas of different types of convergence of a sequence of random variables in probability, namely, statistical convergence of order $\\alpha$ in probability, strong $p$-Ces$\\grave{\\mbox{a}}$ro summability of order $\\alpha$ in probability, lacunary statistical convergence or $S_{\\theta}$-convergence of order $\\alpha$ in probability, ${N_{\\theta}}$-convergence of order $\\alpha$ in probability have been introduced and their certain basic properties have been studied.

  16. Theta angle in holographic QCD

    CERN Document Server

    Jarvinen, Matti

    2016-01-01

    V-QCD is a class of effective holographic models for QCD which fully includes the backreaction of quarks to gluon dynamics. The physics of the theta-angle and the axial anomaly can be consistently included in these models. We analyze their phase diagrams over ranges of values of the quark mass, N_f/N_c, and theta, computing observables such as the topological susceptibility and the meson masses. At small quark mass, where effective chiral Lagrangians are reliable, they agree with the predictions of V-QCD.

  17. Irreversible three-heat-source refrigerator with heat transfer law of Q{alpha}{delta}(T{sup -1}) and its performance optimization based on ECOP criterion

    Energy Technology Data Exchange (ETDEWEB)

    Ngouateu Wouagfack, Paiguy Armand [University of Dschang, L2MSP, Department of Physics, PO Box 67, Dschang (Cameroon); Tchinda, Rene [University of Dschang, LISIE, University Institute of Technology Fotso Victor, PO Box 134, Bandjoun (Cameroon)

    2011-11-15

    The new thermo-ecological optimization of an absorption system for cooling applications operating between three temperature levels with the linear phenomenological heat transfer law of Q{alpha}{delta}(T{sup -} {sup 1}) has been performed by taking account the losses of heat resistance, internal irreversibility and leakage. The considered objective function is the ecological coefficient of performance (ECOP) and is defined as the cooling load per unit loss rate of availability. The comparative analysis with the ecological optimization criterion (E) defined in the literature and also with the cooling load optimization criterion (R) has been carried out to prove the utility of the new thermo-ecological optimization criterion (ECOP) for three-heat-source refrigerators with linear phenomenological heat transfer law. The results show that the three-heat-source refrigeration cycle working at maximum ECOP conditions has a significant advantage in terms of entropy production rate and coefficient of performance over the maximum E and maximum R conditions. The obtained results may provide a general theoretical tool for the thermo-ecological design of absorption refrigerator. (orig.)

  18. Effects of ozone, sulfur dioxide, and alpha and delta races of Colletotrichum Lindemuthianum (Sacc. and Magn. ) Bri and Cav. on bean (Phaseolus vulgaris L. )

    Energy Technology Data Exchange (ETDEWEB)

    Achwanya, O.S.

    1984-01-01

    A number of bean (Phaseolus vulgaris L.) cultivars were evaluated for their responses to the air pollutants ozone and sulfur dioxide singly and in combination, as well as for their reaction to the alpha and delta races of Colletotrichum lindemuthianum (Sacc. and Magn.) Bri and Cav. Variation in response to both the pollutants and the fungus was noted among the cultivars. Anthracnose caused a reduction in the biomass of some cultivars of the order of 50%. A negative correlation of (r = -0.72, p < 0.0001) was found between the disease severity and the total plant biomass. Greater than additive effects of O/sub 3/ + SO/sub 2/ mixtures were demonstrated. Chlorophyll content and biomass were found to be reliable variables for assessing treatment effects. The pollutants appeared to stimulate the disease development. Greater pollutant injury was also in the presence of the anthracnose disease. The results indicated that there was an interaction between the fungal disease and the air pollutants. Implications for evaluating bean cultivars for resistance to C. lindemuthianum under polluted atmosphere are suggested.

  19. Patients with Rheumatoid Arthritis and Chronic Pain Display Enhanced Alpha Power Density at Rest.

    Science.gov (United States)

    Meneses, Francisco M; Queirós, Fernanda C; Montoya, Pedro; Miranda, José G V; Dubois-Mendes, Selena M; Sá, Katia N; Luz-Santos, Cleber; Baptista, Abrahão F

    2016-01-01

    Patients with chronic pain due to neuropathy or musculoskeletal injury frequently exhibit reduced alpha and increased theta power densities. However, little is known about electrical brain activity and chronic pain in patients with rheumatoid arthritis (RA). For this purpose, we evaluated power densities of spontaneous electroencephalogram (EEG) band frequencies (delta, theta, alpha, and beta) in females with persistent pain due to RA. This was a cross-sectional study of 21 participants with RA and 21 healthy controls (mean age = 47.20; SD = 10.40). EEG was recorded at rest over 5 min with participant's eyes closed. Twenty electrodes were placed over five brain regions (frontal, central, parietal, temporal, and occipital). Significant differences were observed in depression and anxiety with higher scores in RA participants than healthy controls (p = 0.002). Participants with RA exhibited increased average absolute alpha power density in all brain regions when compared to controls [F (1.39) = 6.39, p = 0.016], as well as increased average relative alpha power density [F (1.39) = 5.82, p = 0.021] in all regions, except the frontal region, controlling for depression/anxiety. Absolute theta power density also increased in the frontal, central, and parietal regions for participants with RA when compared to controls [F (1, 39) = 4.51, p = 0.040], controlling for depression/anxiety. Differences were not exhibited on beta and delta absolute and relative power densities. The diffuse increased alpha may suggest a possible neurogenic mechanism for chronic pain in individuals with RA.

  20. Patients with Rheumatoid Arthritis and Chronic Pain Display Enhanced Alpha Power Density at Rest

    Science.gov (United States)

    Meneses, Francisco M.; Queirós, Fernanda C.; Montoya, Pedro; Miranda, José G. V.; Dubois-Mendes, Selena M.; Sá, Katia N.; Luz-Santos, Cleber; Baptista, Abrahão F.

    2016-01-01

    Patients with chronic pain due to neuropathy or musculoskeletal injury frequently exhibit reduced alpha and increased theta power densities. However, little is known about electrical brain activity and chronic pain in patients with rheumatoid arthritis (RA). For this purpose, we evaluated power densities of spontaneous electroencephalogram (EEG) band frequencies (delta, theta, alpha, and beta) in females with persistent pain due to RA. This was a cross-sectional study of 21 participants with RA and 21 healthy controls (mean age = 47.20; SD = 10.40). EEG was recorded at rest over 5 min with participant's eyes closed. Twenty electrodes were placed over five brain regions (frontal, central, parietal, temporal, and occipital). Significant differences were observed in depression and anxiety with higher scores in RA participants than healthy controls (p = 0.002). Participants with RA exhibited increased average absolute alpha power density in all brain regions when compared to controls [F(1.39) = 6.39, p = 0.016], as well as increased average relative alpha power density [F(1.39) = 5.82, p = 0.021] in all regions, except the frontal region, controlling for depression/anxiety. Absolute theta power density also increased in the frontal, central, and parietal regions for participants with RA when compared to controls [F(1, 39) = 4.51, p = 0.040], controlling for depression/anxiety. Differences were not exhibited on beta and delta absolute and relative power densities. The diffuse increased alpha may suggest a possible neurogenic mechanism for chronic pain in individuals with RA. PMID:27540360

  1. Different regulation of human delta-opioid receptors by SNC-80 [(+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide] and endogenous enkephalins.

    Science.gov (United States)

    Lecoq, I; Marie, N; Jauzac, Ph; Allouche, S

    2004-08-01

    Among the different mechanisms underlying opioid tolerance, receptor desensitization would represent a major cellular adaptation process in which the role of receptor internalization is still a matter of debate. In the present study, we examined desensitization of the human delta-opioid receptor (hDOR) produced by endogenous opioid peptides Leu-enkephalin (Tyr-Gly-Gly-Phe-Leu) and Met-enkephalin (Tyr-Gly-Gly-Phe-Met), and the contribution of internalization in this process. Results obtained with natural peptides were compared with those produced by a synthetic opioid agonist, SNC-80 [(+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide). After a 30-min treatment, we observed a different regulation of hDOR between agonists. SNC-80 produced a stronger and faster desensitization and was associated with a loss of opioid binding sites by 50%. SNC-80 also caused a marked hDOR down-regulation by 30% as observed by Western blot. Immunocytochemistry revealed that SNC-80 induced a complete redistribution of hDOR from cell surface into intracellular compartments, whereas a partial internalization was visualized upon enkephalin exposure. In contrast, a stronger hDOR recycling and resensitization were measured after enkephalin treatment compared with SNC-80. These data strongly suggested a differential sorting of the internalized receptors caused by enkephalins and SNC-80 that was further confirmed by chloroquine as a lysosomal degradation blocker and monensin as a recycling endosome inhibitor. Finally, by preventing hDOR internalization with 0.5 M sucrose, we demonstrated that hDOR internalization contributes partially to desensitization. In conclusion, hDOR desensitization depends both on its internalization and its sorting either to the recycling pathway or to lysosomes.

  2. Enhanced Constraints on theta13 from A Three-Flavor Oscillation Analysis of Reactor Antineutrinos at KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    The KamLAND Collaboration; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B. D.; Yabumoto, H.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Kadel, R.; O' Donnell, T.; Steiner, H. M.; Dwyer, D. A.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Sakai, M.; Horton-Smith, G. A.; Downum, K. E.; Gratta, G.; Efremenko, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Decowski, M. P.

    2010-09-24

    We present new constraints on the neutrino oscillation parameters {Delta}m{sub 21}{sup 2}, {theta}{sub 12}, and {theta}{sub 13} from a three-flavor analysis of solar and KamLAND data. The KamLAND data set includes data acquired following a radiopurity upgrade and amounts to a total exposure of 3.49 x 10{sup 32} target-proton-year. Under the assumption of CPT invariance, a two-flavor analysis ({theta}{sub 13} = 0) of the KamLAND and solar data yields the best-fit values tan{sup 2} {theta}{sub 12} = 0.444{sub -0.030}{sup +0.036} and {Delta}m{sub 21}{sup 2} = 7.50{sub -0.20}{sup +0.19} x 10{sup -5} eV{sup 2}; a three-flavor analysis with {theta}{sub 13} as a free parameter yields the best-fit values tan{sup 2} {theta}{sub 12} = 0.452{sub -0.033}{sup +0.035}, {Delta}m{sub 21}{sup 2} = 7.50{sub -0.20}{sup +0.19} x 10{sup -5}eV{sup 2}, and sin{sup 2} {theta}{sub 13} = 0.020{sub -0.016}{sup +0.016}. This {theta}{sub 13} interval is consistent with other recent work combining the CHOOZ, atmospheric and long-baseline accelerator experiments. We also present a new global {theta}{sub 13} analysis, incorporating the CHOOZ, atmospheric and accelerator data, which indicates sin{sup 2} {theta}{sub 13} = 0.017{sub -0.009}{sup +0.010}, a nonzero value at the 93% C.L. This finding will be further tested by upcoming accelerator and reactor experiments.

  3. A measurement of sin2 2theta13 with the Double Chooz experiment

    Science.gov (United States)

    Crum, Keith Alan

    The observation of neutrino flavor oscillations provided the first definitive evidence of nonzero neutrino masses and cross-generational mixing in the lepton sector of the Standard Model. Flavor oscillations are characterized by three mixing angles---theta12, theta13, and theta23---as well as two neutrino mass squared differences and three possible CP-violating phases. The Double Chooz experiment was designed to measure the final unmeasured mixing angle theta13 by observing the energy-dependent "disappearance" of electron antineutrinos as they oscillate into the other flavor states. The Double Chooz experiment detects electron antineutrinos in gadolinium-doped liquid scintillator after they interact with a proton via inverse beta decay, yielding a positron that is detected promptly and a neutron that is captured later, either by gadolinium or hydrogen. Separate measurements of theta13 were performed by the Double Chooz collaboration for neutrons which captured on gadolinium and those which captured on hydrogen. This dissertation presents the most recent results of a gadolinium-capture analysis, which used 467.90 live-days of data. Performing a fit to the inverse beta decay positron spectrum, we measured sin 2(2theta13) = 0.090-0.029+0.032 with chi2/d.o.f. = 52.2/40 for the normal neutrino mass hierarchy (Deltam2_ee = (2.44 -0.10 +0.09) * 10. -3eV2). Assuming an inverted neutrino mass hierarchy (Delta m2ee = (2.38-0.10 +0.09) * 10-3 eV2), we find sin2(2theta13) = 0.092-0.029 +0.033 with chi2/d.o.f. = 52.2/40. Additional rate-based measurements of sin2(2theta13) were also performed. These results are in agreement with other reactor theta 13 experiments and represent the most precise measurement of theta 13 at Double Chooz to date.

  4. Measurement and Modeling of Resistivity as a Microscale Tool to Quantify the Volume Fraction of Lenticular (alpha)' Particles in a Partially Transformed (delta)-phase Pu-Ga Matrix

    Energy Technology Data Exchange (ETDEWEB)

    Haslam, J J; Wall, M A; Johnson, D L; Mayhall, D J; Schwartz, A J

    2005-07-13

    We have measured and modeled the change in electrical resistivity due to partial transformation to the martensitic {alpha}{prime}-phase in a {delta}-phase Pu-Ga matrix. The primary objective is to relate the change in resistance, measured with a 4-probe technique during the transformation, to the volume fraction of the {alpha}{prime} phase created in the microstructure. Analysis by finite element methods suggests that considerable differences in the resistivity may be anticipated depending on the orientational and morphological configurations of the {alpha}{prime} particles. Finite element analysis of the computed resistance of an assembly of lenticular shaped particles indicates that series resistor or parallel resistor approximations are inaccurate and can lead to an underestimation of the predicted amount of {alpha}{prime} in the sample by 15% or more. Comparison of the resistivity of a simulated network of partially transformed grains or portions of grains suggests that a correction to the measured resistivity allows quantification of the amount of {alpha}{prime} phase in the microstructure with minimal consideration of how the {alpha}{prime} morphology may evolve. It is found that the average of the series and parallel resistor approximations provide the most accurate relationship between the measured resistivity and the amount of {alpha}{prime} phase. The methods described here are applicable to any evolving two-phase microstructure in which the resistance difference between the two phases is measurable.

  5. The role of TNF-alpha in amygdala kindled rats.

    Science.gov (United States)

    Shandra, A A; Godlevsky, L S; Vastyanov, R S; Oleinik, A A; Konovalenko, V L; Rapoport, E N; Korobka, N N

    2002-02-01

    In the present study, the interaction between epileptogenesis and the immune system were studied in a kindling model. First, the effects of a single administration of TNF-alpha (5.0 microg/kg, i.p.) on seizure and EEG activity were investigated in amygdala-kindled rats. TNF-alpha treated rats showed more prolonged epileptiformic discharges than control rats. TNF-alpha also induced a decrease in the power of delta band and an increase in theta and alpha activity. In addition, a marked increase in the power of beta and gamma band was observed. The EEG changes were most numerous in the frontal cortex and amygdala. All effects were registered 24 h after TNF-alpha administration. Finally, electrical stimulation enhanced the level of TNF-alpha in blood serum from 1.9 +/- 1.5 to 12.7 +/- 3.8 pg/ml and in brain tissue 56.8 +/- 6.0 to 109.2 +/- 6.0 pg/mg, as was determined via the ELISA method. It can be concluded that there is a mutual facilitative interaction of both epileptogenic and cytokine-derived mechanisms on this type of seizure. The changes in the power spectrum of the EEG after TNF-alpha might contribute to intensify thalamic-derived facilitation of epileptic discharge in cortical structures.

  6. Simultaneous application of slow-oscillation transcranial direct current stimulation and theta burst stimulation prolongs continuous theta burst stimulation-induced suppression of corticomotor excitability in humans.

    Science.gov (United States)

    Doeltgen, Sebastian H; McAllister, Suzanne M; Ridding, Michael C

    2012-09-01

    The objective of this study was to assess whether the simultaneous application of slow-oscillation transcranial direct current stimulation enhances the neuroplastic response to transcranial magnetic theta burst stimulation. Motor evoked potential amplitude was assessed at baseline and at regular intervals up to 60 min following continuous theta burst stimulation, slow-oscillation transcranial direct current stimulation, and the simultaneous application of these paradigms. In addition, the electroencephalographic power spectra of slow and fast delta, and theta frequency bands recorded over the motor cortex were analyzed prior to and up to 5 min following each intervention. There was longer-lasting motor evoked potential suppression following the simultaneous application of continuous theta burst stimulation and slow-oscillation transcranial direct current stimulation compared with when continuous theta burst stimulation was applied alone. Slow-oscillation transcranial direct current stimulation applied alone did not modulate the motor evoked potential amplitude. No significant changes in spectral power were observed following slow-oscillation transcranial direct current stimulation. Simultaneous application of continuous theta burst stimulation and slow-oscillation transcranial direct current stimulation may provide an approach to prolong the induction of neuroplastic changes in motor cortical circuits by repetitive transcranial magnetic brain stimulation.

  7. Inhibition of protein kinase C delta attenuates allergic airway inflammation through suppression of PI3K/Akt/mTOR/HIF-1 alpha/VEGF pathway.

    Directory of Open Access Journals (Sweden)

    Yun Ho Choi

    Full Text Available Vascular endothelial growth factor (VEGF is supposed to contribute to the pathogenesis of allergic airway disease. VEGF expression is regulated by a variety of stimuli such as nitric oxide, growth factors, and hypoxia-inducible factor-1 alpha (HIF-1α. Recently, inhibition of the mammalian target of rapamycin (mTOR has been shown to alleviate cardinal asthmatic features, including airway hyperresponsiveness, eosinophilic inflammation, and increased vascular permeability in asthma models. Based on these observations, we have investigated whether mTOR is associated with HIF-1α-mediated VEGF expression in allergic asthma. In studies with the mTOR inhibitor rapamycin, we have elucidated the stimulatory role of a mTOR-HIF-1α-VEGF axis in allergic response. Next, the mechanisms by which mTOR is activated to modulate this response have been evaluated. mTOR is known to be regulated by phosphoinositide 3-kinase (PI3K/Akt or protein kinase C-delta (PKC δ in various cell types. Consistent with these, our results have revealed that suppression of PKC δ by rottlerin leads to the inhibition of PI3K/Akt activity and the subsequent blockade of a mTOR-HIF-1α-VEGF module, thereby attenuating typical asthmatic attack in a murine model. Thus, the present data indicate that PKC δ is necessary for the modulation of the PI3K/Akt/mTOR signaling cascade, resulting in a tight regulation of HIF-1α activity and VEGF expression. In conclusion, PKC δ may represent a valuable target for innovative therapeutic treatment of allergic airway disease.

  8. Theta height and Faltings height

    CERN Document Server

    Pazuki, F

    2009-01-01

    Using original ideas from J.-B. Bost and S. David, we provide an explicit comparison between the Theta height and the stable Faltings height of a principally polarized abelian variety. We also give as an application an explicit upper bound on the number of K-rational points of a curve of genus g>1 over a number filed K under a conjecture of S. Lang and J. Silverman. We complete the study with a comparison between differential lattice structures.

  9. Charged current weak electroproduction of $\\Delta$ resonance

    CERN Document Server

    Alvarez-Ruso, L; Vacas, M J V

    1998-01-01

    We study the weak production of $\\Delta$ (i.e. $e^{-} + p \\to \\Delta^{0}+ energy range corresponding to the Mainz and TJNAF electron accelerators. The differential cross sections $\\sigma(\\theta)$ are found to be of the order of $ 10^{-39}$ cm$^2$/sr, over a range of angles which increases with energy. The possibility of observing these reactions with the high luminosities available at these accelerators, and studying the weak N-$\\Delta$ transition form factors through these reactions is discussed. The production cross section of N$^*(1440)$ in the kinematic region of $\\Delta$ production is also estimated and found to be small.

  10. Theta dependence in Holographic QCD

    CERN Document Server

    Bartolini, Lorenzo; Bolognesi, Stefano; Cotrone, Aldo L; Manenti, Andrea

    2016-01-01

    We study the effects of the CP-breaking topological $\\theta$-term in the large $N_c$ QCD model by Witten, Sakai and Sugimoto with $N_f$ degenerate light flavors. We first compute the ground state energy density, the topological susceptibility and the masses of the lowest lying mesons, finding agreement with expectations from the QCD chiral effective action. Then, focusing on the $N_f=2$ case, we consider the baryonic sector and determine, to leading order in the small $\\theta$ regime, the related holographic instantonic soliton solutions. We find that while the baryon spectrum does not receive ${\\cal O}(\\theta)$ corrections, this is not the case for observables like the electromagnetic form factor of the nucleons. In particular, it exhibits a dipole term, which turns out to be vector-meson dominated. The resulting neutron electric dipole moment, which is exactly the opposite as that of the proton, is of the same order of magnitude of previous estimates in the literature. Finally, we compute the CP-violating p...

  11. Trimaximal mixing with predicted {theta}{sub 13} from a new type of constrained sequential dominance

    Energy Technology Data Exchange (ETDEWEB)

    Antusch, Stefan, E-mail: stefan.antusch@unibas.ch [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Muenchen (Germany); King, Stephen F., E-mail: king@soton.ac.uk [School of Physics and Astronomy, University of Southampton, SO17 1BJ Southampton (United Kingdom); Luhn, Christoph, E-mail: christoph.luhn@soton.ac.uk [School of Physics and Astronomy, University of Southampton, SO17 1BJ Southampton (United Kingdom); Spinrath, Martin, E-mail: spinrath@sissa.it [SISSA/ISAS and INFN, Via Bonomea 265, I-34136 Trieste (Italy)

    2012-03-11

    Following the recent T2K indication of a sizeable reactor angle, we present a class of models which fix {theta}{sub 13} while preserving trimaximal solar mixing. The models are based on a new type of constrained sequential dominance involving new vacuum alignments, along the (1,2,0){sup T} or (1,0,2){sup T} directions in flavour space. We show that such alignments are easily achieved using orthogonality, and may replace the role of the subdominant flavon alignment (1,1,1){sup T} in constrained sequential dominance. In such models, with a normal hierarchical spectrum, the reactor angle is related to a ratio of neutrino masses by {theta}{sub 13}=({radical}(2))/3 (m{sub 2}{sup {nu}})/(m{sub 3}{sup {nu}}) , leading to {theta}{sub 13}{approx}5 Degree-Sign -6 Degree-Sign , while the atmospheric angle is given by the sum rule {theta}{sub 23} Almost-Equal-To 45 Degree-Sign +{radical}(2){theta}{sub 13}cos{delta}. We find that leptogenesis is unsuppressed due to the violation of form dominance and that the CP violating phase responsible for leptogenesis is precisely equal to the Dirac CP phase {delta}, providing a direct link between leptogenesis and neutrino mixing in this class of models.

  12. Exploring the sensitivity of current and future experiments to $\\theta_{\\odot}$

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati

    2003-01-01

    The first results from the KamLAND experiment in conjunction with the global solar neutrino data has demonstrated striking ability to constrain the $\\Delta m^2_\\odot$ ($\\Delta m^2_{21}$) very precisely. However the allowed range of $\\theta_{\\odot}$ ($\\theta_{12}$) did not change much with the inclusion of the KamLAND results. In this paper we probe if future data from KamLAND can increase the accuracy of the allowed range in $\\theta_{\\odot}$ and conclude that even after 3 kton-year of statistics, KamLAND may find it hard to improve the bounds on the mixing angle obtained from the current solar neutrino data. We discuss the $\\theta_{12}$ sensitivity of the survival probabilities in matter (vacuum) as is relevant for the solar (KamLAND) experiments. We find that the presence of matter effects in the survival probabilities for $^8B$ neutrinos give the solar neutrino experiments SK and SNO an edge over KamLAND, as far as $\\theta_{12}$ sensitivity is concerned, particularly near maximal mixing. Among solar neutrin...

  13. Sheep (Ovis aries) T cell receptor alpha (TRA) and delta (TRD) genes and genomic organization of the TRA/TRD locus.

    Science.gov (United States)

    Piccinni, Barbara; Massari, Serafina; Caputi Jambrenghi, Anna; Giannico, Francesco; Lefranc, Marie-Paule; Ciccarese, Salvatrice; Antonacci, Rachele

    2015-09-18

    In mammals, T cells develop along two discrete pathways characterized by expression of either the αβ or the γδ T cell receptors. Human and mouse display a low peripheral blood γδ T cell percentage ("γδ low species") while sheep, bovine and pig accounts for a high proportion of γδ T lymphocytes ("γδ high species"). While the T cell receptor alpha (TRA) and delta (TRD) genes and the genomic organization of the TRA/TRD locus has been determined in human and mouse, this information is still poorly known in artiodactyl species, such as sheep. The analysis of the current Ovis aries whole genome assembly, Oar_v3.1, revealed that, as in the other mammalian species, the sheep TRD locus is nested within the TRA locus. In the most 5' part the TRA/TRD locus contains TRAV genes which are intermingled with TRDV genes, then TRD genes which include seven TRDD, four TRDJ genes, one TRDC and a single TRDV gene with an inverted transcriptional orientation, and finally in the most 3' part, the TRA locus is completed by 61 TRAJ genes and one TRAC gene. Comparative sequence and analysis and annotation led to the identification of 66 TRAV genes assigned to 34 TRAV subgroups and 25 TRDV genes belonging to the TRDV1 subgroup, while one gene was found for each TRDV2, TRDV3 and TRDV4 subgroups. Multiple duplication events within several TRAV subgroups have generated the sheep TRAV germline repertoire, which is substantially larger than the human one. A significant proportion of these TRAV gene duplications seems to have occurred simultaneously with the amplification of the TRDV1 subgroup genes. This dynamic of expansion has also generated novel multigene subgroups, which are species-specific. Ovis aries TRA and TRD genes identified in this study were assigned IMGT definitive or temporary names and were approved by the IMGT/WHO-IUIS nomenclature committee. The completeness of the genome assembly in the 3' part of the locus has allowed us to interpret rearranged CDR3 of cDNA from

  14. QCD at $\\Theta \\sim \\pi$

    CERN Document Server

    Smilga, A V

    1999-01-01

    Taking into account the quadratic in quark mass terms in the effective chiral lagrangian, we show that, at \\theta \\sim \\pi, the theory with 2 light quarks of equal mass involves two degenerate vacuum states separated by a barrier. For three flavors, the energy barrier between two vacua appears already in the leading order in mass. This corresponds to the first order phase transition at different vacua is calculated. In the immediate vicinity of the phase transition point, two minima of the potential still exist, but one of them becomes metastable. The probability of the false vacuum decay is estimated.

  15. Algebraic geometry and theta functions

    CERN Document Server

    Coble, Arthur B

    1929-01-01

    This book is the result of extending and deepening all questions from algebraic geometry that are connected to the central problem of this book: the determination of the tritangent planes of a space curve of order six and genus four, which the author treated in his Colloquium Lecture in 1928 at Amherst. The first two chapters recall fundamental ideas of algebraic geometry and theta functions in such fashion as will be most helpful in later applications. In order to clearly present the state of the central problem, the author first presents the better-known cases of genus two (Chapter III) and

  16. Enhanced pre-synaptic glutamate release in deep-dorsal horn contributes to calcium channel alpha-2-delta-1 protein-mediated spinal sensitization and behavioral hypersensitivity

    Directory of Open Access Journals (Sweden)

    Dickenson Anthony H

    2009-02-01

    Full Text Available Abstract Nerve injury-induced expression of the spinal calcium channel alpha-2-delta-1 subunit (Cavα2δ1 has been shown to mediate behavioral hypersensitivity through a yet identified mechanism. We examined if this neuroplasticity modulates behavioral hypersensitivity by regulating spinal glutamatergic neurotransmission in injury-free transgenic mice overexpressing the Cavα2δ1 proteins in neuronal tissues. The transgenic mice exhibited hypersensitivity to mechanical stimulation (allodynia similar to the spinal nerve ligation injury model. Intrathecally delivered antagonists for N-methyl-D-aspartate (NMDA and α-amino-3-hydroxyl-5-methylisoxazole-4-propionic acid (AMPA/kainate receptors, but not for the metabotropic glutamate receptors, caused a dose-dependent allodynia reversal in the transgenic mice without changing the behavioral sensitivity in wild-type mice. This suggests that elevated spinal Cavα2δ1 mediates allodynia through a pathway involving activation of selective glutamate receptors. To determine if this is mediated by enhanced spinal neuronal excitability or pre-synaptic glutamate release in deep-dorsal horn, we examined wide-dynamic-range (WDR neuron excitability with extracellular recording and glutamate-mediated excitatory postsynaptic currents with whole-cell patch recording in deep-dorsal horn of the Cavα2δ1 transgenic mice. Our data indicated that overexpression of Cavα2δ1 in neuronal tissues led to increased frequency, but not amplitude, of miniature excitatory post synaptic currents mediated mainly by AMPA/kainate receptors at physiological membrane potentials, and also by NMDA receptors upon depolarization, without changing the excitability of WDR neurons to high intensity stimulation. Together, these findings support a mechanism of Cavα2δ1-mediated spinal sensitization in which elevated Cavα2δ1 causes increased pre-synaptic glutamate release that leads to reduced excitation thresholds of post-synaptic dorsal

  17. Developmental Changes in Hippocampal CA1 Single Neuron Firing and Theta Activity during Associative Learning

    Science.gov (United States)

    Kim, Jangjin; Goldsberry, Mary E.; Harmon, Thomas C.; Freeman, John H.

    2016-01-01

    Hippocampal development is thought to play a crucial role in the emergence of many forms of learning and memory, but ontogenetic changes in hippocampal activity during learning have not been examined thoroughly. We examined the ontogeny of hippocampal function by recording theta and single neuron activity from the dorsal hippocampal CA1 area while rat pups were trained in associative learning. Three different age groups [postnatal days (P)17-19, P21-23, and P24-26] were trained over six sessions using a tone conditioned stimulus (CS) and a periorbital stimulation unconditioned stimulus (US). Learning increased as a function of age, with the P21-23 and P24-26 groups learning faster than the P17-19 group. Age- and learning-related changes in both theta and single neuron activity were observed. CA1 pyramidal cells in the older age groups showed greater task-related activity than the P17-19 group during CS-US paired sessions. The proportion of trials with a significant theta (4–10 Hz) power change, the theta/delta ratio, and theta peak frequency also increased in an age-dependent manner. Finally, spike/theta phase-locking during the CS showed an age-related increase. The findings indicate substantial developmental changes in dorsal hippocampal function that may play a role in the ontogeny of learning and memory. PMID:27764172

  18. Nonzero theta(13) for neutrino mixing in the context of A(4) symmetry

    CERN Document Server

    Ma, Ernest

    2011-01-01

    In the original 2004 paper which first derived tribimaximal mixing in the context of A(4), i.e. the non-Abelian finite symmetry group of the tetrahedron (Plato's fire), as its simplest application, it was also pointed out how theta(13) nonzero may be accommodated. On the strength of the new T2K result that 0.03 (0.04) < sin^2 2 theta(13) < 0.28 (0.34) for delta(CP)=0 and normal (inverted) neutrino mass hierarchy, we perform a more detailed analysis of how this original idea may be realized in the context of A(4).

  19. Social exclusion modulates event-related frontal theta and tracks ostracism distress in children.

    Science.gov (United States)

    van Noordt, Stefon J R; White, Lars O; Wu, Jia; Mayes, Linda C; Crowley, Michael J

    2015-09-01

    Social exclusion is a potent elicitor of distress. Previous studies have shown that medial frontal theta oscillations are modulated by the experience of social exclusion. Using the Cyberball paradigm, we examined event-related dynamics of theta power in the EEG at medial frontal sites while children aged 8-12 years were exposed to conditions of fair play and social exclusion. Using an event-related design, we found that medial frontal theta oscillations (4-8Hz) increase during both early (i.e., 200-400ms) and late (i.e., 400-800ms) processing of rejection events during social exclusion relative to perceptually identical "not my turn" events during inclusion. Importantly, we show that only for the later time window (400-800ms) slow-wave theta power tracks self-reported ostracism distress. Specifically, greater theta power at medial frontal sites to "rejection" events predicted higher levels of ostracism distress. Alpha and beta oscillations for rejection events were unrelated to ostracism distress at either 200-400ms or 400-800ms time windows. Our findings extend previous studies by showing that medial frontal theta oscillations for rejection events are a neural signature of social exclusion, linked to experienced distress in middle childhood.

  20. TNF-alpha inhibits 3T3-L1 adipocyte differentiation without downregulating the expression of C/EBPbeta and delta.

    Science.gov (United States)

    Kurebayashi, S; Sumitani, S; Kasayama, S; Jetten, A M; Hirose, T

    2001-04-01

    Tumor necrosis factor-alpha (TNF-alpha) has been reported to inhibit adipocyte differentiation in which multiple transcription factors including CCAAT enhancer binding proteins (C/EBPs) and peroxisome proliferator-activated receptor (PPAR) gamma play an important role. Induction of C/EBPalpha and PPARgamma, which regulate the expression of many adipocyte-related genes, is dependent on the expression of C/EBPbeta and C/EBPdelta at the early phase of adipocyte differentiation. To elucidate the mechanism by which TNF-alpha inhibits adipocyte differentiation, we examined the effect of TNF-alpha on the expression of these transcription factors in mouse 3T3-L1 preadipocytes. TNF-alpha did not abrogate the induction of C/EBPbeta and C/EBPdelta in response to differentiation stimuli. In fully differentiated adipocytes, TNF-alpha rapidly induced C/EBPbeta and C/EBPdelta, whereas it downregulated the expression of C/EBPalpha and PPARgamma. Our results suggest that TNF-alpha inhibits adipocyte differentiation independently of the downregulation of C/EBPbeta and C/EBPdelta.

  1. Predictive nature of prefrontal theta oscillation on the performance of trace conditioned eyeblink responses in guinea pigs.

    Science.gov (United States)

    Chen, Hao; Wang, Yi-jie; Yang, Li; Hu, Chen; Ke, Xian-feng; Fan, Zheng-li; Sui, Jian-feng; Hu, Bo

    2014-05-15

    Stimulus-evoked theta oscillations are observed in the medial prefrontal cortex (mPFC) when executing a variety of learning tasks. Here, we aimed to further determine whether spontaneous theta-band (5.0-10.0 Hz) oscillations in the mPFC predicted the subsequent behavioral performance in trace eyeblink conditioning (TEBC), in which the conditioned stimulus (CS) was separated from the unconditioned stimulus (US) by 500 ms trace interval. By recording local field potentials (LFP) signals in the guinea pigs performing the TEBC task, we found that, a higher mPFC relative theta ratio [theta/(delta+beta)] during the baseline (850-ms period prior to the onset of the CS) was predictive of higher magnitude and more adaptive timing rather than faster acquisition of trace conditioned eyeblink responses (CR). However, the prediction of baseline mPFC theta activity was time-limited to the well-learning stage. Additionally, the relative power of mPFC theta activity did not correlate with the CR performance if the trace interval between the CS and the US was shortened to 100 ms. These results suggest that the brain state in which the baseline mPFC theta activity is present or absent is detrimental for the subsequent performance of trace CRs especially when the asymptotic learning state is achieved.

  2. The Line-Profile Variations of Theta2 Tauri

    Science.gov (United States)

    Kennelly, E. J.; Walker, G. A. H.

    1996-04-01

    With a 5.4-hour time series of high-resolution CFHT spectra, the oscillations of the rapidly-rotating delta Scuti star Theta2 Tauri (A7 IV + A5 V) are investigated. Line-profile variations are discovered and identified with the spectrum of the primary star of this binary system. Radial velocity variations are derived from the data and analyzed to reveal an oscillation frequency near 13.7 cycles day^-1. Variations within the absorption profiles are analyzed with a Fourier-Doppler Imaging (FDI) technique to reveal that high-degree oscillations with a frequency of 16.1 cycles day ^-1 and an apparent degree of about l = 8 are also present in the star. Whereas the low-degree variations of Theta2 Tau have been shown to be consistent with p-modes of radial order n=2 or 3, the identification of the high-degree variations in terms of pressure modes requires confirmation with theoretical models. (SECTION: Stars)

  3. The Neutrino Mass Hierarchy at Reactor Experiments now that theta13 is Large

    CERN Document Server

    Ciuffoli, Emilio; Zhang, Xinmin

    2012-01-01

    Now that theta13 is known to be large, a medium baseline reactor experiment can observe the fine structure of the electron antineutrino survival probability curve, approximately periodic oscillations in L/E with wavelength 4pi/Delta M^2_31. The periodicity with respect to L/E is broken by 2-3 oscillations which, in the case of the normal (inverted) hierarchy, shift the first 16 oscillations nearly 1% higher (lower) and move the next 16 lower (higher). The energy of each peak determines a particular combination of the mass differences, for example cos^2(theta12)Delta M^2_31 + sin^2(theta12)Delta M^2_32 for all peaks visible at baselines under 40 km. Comparing these combinations with each other or with NOvA results one can in principle determine the mass hierarchy. Alternately, as the Fourier transforms of the 1-3 and 2-3 oscillation probabilities are out of phase by the 1-2 oscillation probability, near the maximum of the 1-2 oscillation the complex phase of the total survival probability can be used to determ...

  4. Spectral determinants and quantum theta functions

    Science.gov (United States)

    Grassi, Alba

    2016-12-01

    It has been recently conjectured that the spectral determinants of operators associated to mirror curves can be expressed in terms of a generalization of theta functions, called quantum theta functions. In this paper we study the symplectic properties of these spectral determinants by expanding them around the point {\\hslash }=2π , where the quantum theta functions become conventional theta functions. We find that they are modular invariant, order by order, and we give explicit expressions for the very first terms of the expansion. Our derivation requires a detailed understanding of the modular properties of topological string free energies in the Nekrasov-Shatashvili limit. We derive these properties in a diagrammatic form. Finally, we use our results to provide a new test of the duality between topological strings and spectral theory.

  5. On Probing theta_{23} in Neutrino Telescopes

    CERN Document Server

    Choubey, Sandhya; Rodejohann, Werner

    2008-01-01

    Among all neutrino mixing parameters, the atmospheric neutrino mixing angle theta_{23} introduces the strongest variation on the flux ratios of ultra high energy neutrinos. We investigate the potential of these flux ratio measurements at neutrino telescopes to constrain theta_{23}. We consider astrophysical neutrinos originating from pion, muon-damped and neutron sources and make a comparative study of their sensitivity reach to theta_{23}. It is found that neutron sources are most favorable for testing deviations from maximal theta_{23}. Using a chi^2 analysis, we show in particular the power of combining (i) different flux ratios from the same type of source, and also (ii) combining flux ratios from different astrophysical sources. We include in our analysis ``impure'' sources, i.e., deviations from the usually assumed initial (1 : 2 : 0), (0 : 1 : 0) or (1 : 0 : 0) flux compositions.

  6. On the Orbit of Visual Binary ADS 8119 AB ({\\alpha} = 11h18m10s.9 and {\\delta}=+31o31'44".9)

    CERN Document Server

    Siregar, S

    2010-01-01

    Xi UrsaMajoris ({\\xi} Uma) historically is one of the most important double star inconstellation Ursa Major, found by Sir William Herschel on May, 2, 1780 and the first binary successfully determined by using the principle of two body problem in 1828 by Savary. This star consists of two pair wide binary ADS8119 AB; in this case HD 98231(ADS8119 A) as primary and HD98230 (ADS 8119 B) as secondary. We have collected the observational data consist of separation angular ({\\rho}) and position angle ({\\theta}) fromthe observations in 1780 up to 2005 taken from Bosscha Observatory and other Observatories in the world. This paper presents the recent status of orbit binary system ADS 8119. By using Thiele Van den Bos method and empirical formula Strand's Mass-Luminosity relation we have determined the orbit and mass of ADS 8119AB. The result is; Orbital and Physical Element of ADS 8119 AB. Dynamical Elements, Orbit Orientation, Masses-Parallax; P = 60 years, e = 0.426, T = 1935.8, i = 110o9, {\\Omega} = 104o.7, {\\omega...

  7. Geometric relation for neutrino mixing angles and theta(13)

    CERN Document Server

    Lipmanov, E M

    2011-01-01

    Inspired by the recent T2K discovery of a relatively large theta(13) angle in the neutrino mixing matrix we propose here a simple geometric relation between the three usually thought "independent" neutrino mixing angles - solar {\\theta}12, atmospheric {\\theta}23 and reactor {\\theta}13 ones: cos2(2{\\theta}sol) + cos2(2{\\theta}atm) + cos2(2{\\theta}13) = 1. Using the estimations for the two largest neutrino mixing angles from experimental data analyses in the literature, {\\theta}sol{\\cong} ~ 34.4o, {\\theta}atm{\\cong} ~ 42.8o, the reactor neutrino mixing angle is uniquely predicted {\\theta}13 = 10.8o. In case a little changed data, {\\theta}sol{\\cong} = 34o and {\\theta}atm{\\cong} = 43o the result will be {\\theta}13 =11.2o. And so, the {\\theta}13-value is not very sensitive to the accurate magnitudes of the two largest mixing angles. That prediction for the 'small' neutrino mixing angle is compatible with the latest T2K experimental data with best fit values for the reactor angle ({\\theta}13)bf{\\cong}= 9.7o(11o) fo...

  8. The YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} anomalous second peak and irreversible magnetic field in the magnetization hysteresis cycles

    Energy Technology Data Exchange (ETDEWEB)

    Taoufik, A.; Ramzi, A.; Labrag, A. [Laboratoire des Materiaux Supraconducteurs a Haute Temperature Critique, Departement de Physique, Faculte des Sciences, Universite Ibn Zohr, B.P. 8106, Agadir (Morocco); Senoussi, S. [Laboratoire de Physique des Solides (associe au CNRS. URA. 0002), Universite Paris Sud, Batiment 510, 91405 Orsay Cedex (France)

    2004-05-01

    The flux jumps, the second peak and the irreversible magnetic field in the magnetization hysteresis cycles have been investigated in the high temperature superconductor YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} single crystals. These cycles were obtained for different temperature values, the applied magnetic fields up to 6 T and the angle {theta} between the applied magnetic field and c-axis. The magnetization curves exhibit a remarkable second peak ''fishtail'', this second peak was not observed for the low temperature, but we observed the flux jumps ''saw tooth''. The temperature dependence of the irreversible magnetic field, H{sub irr}, for the applied magnetic field perpendicular to the ab planes is given by an extended expression, H{sub irr}{alpha}(1-T/T {sub c}) {sup {alpha}}, where {alpha} is a constant, the Abrikosov flux dynamics can explain this behavior. The H {sub irr} as a function of {theta} has been strongly influenced by the flux pinning and the thermally assisted flux motion. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Comparison between delta C-13 of alpha-cellulose and bulk wood in the mangrove tree Rhizophora mucronata: Implications for dendrochemistry

    OpenAIRE

    Verheyden, A.; Roggeman, M; Bouillon, Steven; Elskens, Marc; BEECKMAN, H.; Koedam, N.

    2005-01-01

    Stable carbon isotope analysis of tree rings has become a widely used proxy in environmental and palaeoclimatological studies. In those studies, alpha-cellulose has often been the preferred material because of its singular composition and its immobility in wood. However, cellulose extraction is a time-consuming procedure and since the development of on-line isotope ratio mass spectrometers has become the time-limiting step in the isotopic analysis of wood samples for dendrochemical purposes. ...

  10. Modeling the formation of secondary organic aerosol. 1. Application of theoretical principles to measurements obtained in the alpha-pinene/, beta-pinene/, sabinene/, delta3-carene/, and cyclohexane/ozone systems.

    Science.gov (United States)

    Pankow, J F; Seinfeld, J H; Asher, W E; Erdakos, G B

    2001-03-15

    Secondary organic aerosol (SOA) forms in the atmosphere when volatile parent compounds are oxidized to form low-volatility products that condense to yield organic particulate matter (PM). Under conditions of intense photochemical smog, from 40 to 80% of the particulate organic carbon can be secondary in origin. Because describing multicomponent condensation requires a compound-by-compound identification and quantification of the condensable compounds, the complexity of ambient SOA has made it difficult to test the ability of existing gas/particle (G/P) partitioning theory to predict SOA formation in urban air. This paper examines that ability using G/P data from past laboratory chamber experiments carried out with five parent hydrocarbons (HCs) (four monoterpenes at 308 K and cyclohexene at 298 K) in which significant fractions (61-100%) of the total mass of SOA formed from those HCs were identified and quantified by compound. The model calculations were based on a matrix representation of the multicomponent, SOA G/P distribution process. The governing equations were solved by an iterative method. Input data forthe model included (i) deltaHC (microg m(-3)), the amount of reacted parent hydrocarbon; (ii) the alpha values that give the total concentration T (gas + particle phase, ng m(-3)) values for each product i according to Ti = 10(3) alphaideltaHC; (iii) estimates of the pure compound liquid vapor pressure pL(degrees) values (at the reaction temperature) for the products; and (iv) UNIFAC parameters for estimating activity coefficients in the SOA phase for the products as a function of SOA composition. The model predicts the total amount Mo (microg m(-3)) of organic aerosol that will form from the reaction of deltaHC, the total aerosol yield Y(= Mo/deltaHC), and the compound-by-compound yield values Yi. An impediment in applying the model is the lack of literature data on PL(degrees) values for the compounds of interest or even on pL(degrees) values for other

  11. Genomic and expression analyses of Tursiops truncatus T cell receptor gamma (TRG) and alpha/delta (TRA/TRD) loci reveal a similar basic public γδ repertoire in dolphin and human.

    Science.gov (United States)

    Linguiti, Giovanna; Antonacci, Rachele; Tasco, Gianluca; Grande, Francesco; Casadio, Rita; Massari, Serafina; Castelli, Vito; Consiglio, Arianna; Lefranc, Marie-Paule; Ciccarese, Salvatrice

    2016-08-15

    The bottlenose dolphin (Tursiops truncatus) is a mammal that belongs to the Cetartiodactyla and have lived in marine ecosystems for nearly 60 millions years. Despite its popularity, our knowledge about its adaptive immunity and evolution is very limited. Furthermore, nothing is known about the genomics and evolution of dolphin antigen receptor immunity. Here we report a evolutionary and expression study of Tursiops truncatus T cell receptor gamma (TRG) and alpha/delta (TRA/TRD) genes. We have identified in silico the TRG and TRA/TRD genes and analyzed the relevant mature transcripts in blood and in skin from four subjects. The dolphin TRG locus is the smallest and simplest of all mammalian loci as yet studied. It shows a genomic organization comprising two variable (V1 and V2), three joining (J1, J2 and J3) and a single constant (C), genes. Despite the fragmented nature of the genome assemblies, we deduced the TRA/TRD locus organization, with the recent TRDV1 subgroup genes duplications, as it is expected in artiodactyls. Expression analysis from blood of a subject allowed us to assign unambiguously eight TRAV genes to those annotated in the genomic sequence and to twelve new genes, belonging to five different subgroups. All transcripts were productive and no relevant biases towards TRAV-J rearrangements are observed. Blood and skin from four unrelated subjects expression data provide evidence for an unusual ratio of productive/unproductive transcripts which arise from the TRG V-J gene rearrangement and for a "public" gamma delta TR repertoire. The productive cDNA sequences, shared both in the same and in different individuals, include biases of the TRGV1 and TRGJ2 genes. The high frequency of TRGV1-J2/TRDV1- D1-J4 productive rearrangements in dolphins may represent an interesting oligo-clonal population comparable to that found in human with the TRGV9- JP/TRDV2-D-J T cells and in primates. Although the features of the TRG and TRA/TRD loci organization reflect

  12. Learning alters theta amplitude, theta-gamma coupling and neuronal synchronization in inferotemporal cortex

    Directory of Open Access Journals (Sweden)

    Nicol Alister U

    2011-06-01

    Full Text Available Abstract Background How oscillatory brain rhythms alone, or in combination, influence cortical information processing to support learning has yet to be fully established. Local field potential and multi-unit neuronal activity recordings were made from 64-electrode arrays in the inferotemporal cortex of conscious sheep during and after visual discrimination learning of face or object pairs. A neural network model has been developed to simulate and aid functional interpretation of learning-evoked changes. Results Following learning the amplitude of theta (4-8 Hz, but not gamma (30-70 Hz oscillations was increased, as was the ratio of theta to gamma. Over 75% of electrodes showed significant coupling between theta phase and gamma amplitude (theta-nested gamma. The strength of this coupling was also increased following learning and this was not simply a consequence of increased theta amplitude. Actual discrimination performance was significantly correlated with theta and theta-gamma coupling changes. Neuronal activity was phase-locked with theta but learning had no effect on firing rates or the magnitude or latencies of visual evoked potentials during stimuli. The neural network model developed showed that a combination of fast and slow inhibitory interneurons could generate theta-nested gamma. By increasing N-methyl-D-aspartate receptor sensitivity in the model similar changes were produced as in inferotemporal cortex after learning. The model showed that these changes could potentiate the firing of downstream neurons by a temporal desynchronization of excitatory neuron output without increasing the firing frequencies of the latter. This desynchronization effect was confirmed in IT neuronal activity following learning and its magnitude was correlated with discrimination performance. Conclusions Face discrimination learning produces significant increases in both theta amplitude and the strength of theta-gamma coupling in the inferotemporal cortex

  13. Measuring Theta_13 at Daya Bay

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Kwong [Univ. of Houston, TX (United States)

    2014-03-14

    We measured the neutrino mixing angle, theta13, presumably related to the preponderance of matter over antimatter in our universe with high precision. We determined theta13 by measuring the disappearance of neutrinos from a group of six nuclear reactors. The target, located inside a mountain at about 2 km from the reactors, is 80 tons of liquid scintillator doped with trace amount of Gadolinium to increase its neutron detection efficiency. The neutrino flux is measured by the inverse beta-decay reaction where the final-state particles are detected by the liquid scintillator. The measured value of theta13, based on data collected over 3 years, is large, around 8 degrees, rendering the measurement of the parameter related to matter-antimatter asymmetry in future long baseline neutrino experiments easier.

  14. Search for the {theta}{sub 13} mixing angle with the Double Chooz experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gil-Botella, Ines, E-mail: ines.gil@ciemat.es [CIEMAT, Basic Research Department, Avenida Complutense, 22, 28040 Madrid (Spain)

    2010-11-01

    The Double Chooz reactor neutrino experiment will search for a non vanishing {theta}{sub 13} mixing angle with unprecedented sensitivity, which might open the way to unveiling CP violation in the leptonic sector. The measurement of this angle will be based in a precise comparison of the antineutrino spectrum at two identical detectors located at different distances from the Chooz nuclear reactor cores in France. Double Chooz is particularly attractive because of its capability to measure sin{sup 2}(2{theta}{sub 13}) to 3{sigma} if sin{sup 2}(2{theta}{sub 13}) > 0.05 or to exclude sin{sup 2}(2{theta}{sub 13}) down to 0.03 at 90% C.L. for {Delta}m{sup 2}{sub 31} = 2.5 x 10{sup -3} eV{sup 2} in three years of data taking with both detectors. The installation of the far detector at 1 km from the reactors is almost completed and the first neutrino interactions are expected by end 2010.

  15. Measuring $\\theta_{13}$ via Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Toner, Ruth B. [Univ. of Cambridge (United Kingdom). Pembroke College

    2011-01-01

    One of the primary goals in neutrino physics at the present moment is to make a measurement of the neutrino oscillation parameter $\\theta_{13}$. This parameter, in addition to being unknown, could potentially allow for the introduction of CP violation into the lepton sector. The MINOS long-baseline neutrino oscillation experiment has the ability to make a measurement of this parameter, by looking for the oscillation of muon neutrinos to electron neutrinos between a Near and Far Detector over a distance of 735 km. This thesis discusses the development of an analysis framework to search for this oscillation mode. Two major improvements to pre-existing analysis techniques have been implemented by the author. First, a novel particle ID technique based on strip topology, known as the Library Event Matching (LEM) method, is optimized for use in MINOS. Second, a multiple bin likelihood method is developed to fit the data. These two improvements, when combined, increase MINOS' sensitivity to $\\sin^2(2\\theta_{13})$ by 27\\% over previous analyses. This thesis sees a small excess over background in the Far Detector. A Frequentist interpretation of the data rules out $\\theta_{13}=0$ at 91\\%. A Bayesian interpretation of the data is also presented, placing the most stringent upper boundary on the oscillation parameter to date, at $\\sin^2(2\\theta_{13})<0.09(0.015)$ for the Normal (Inverted) Hierarchy and $\\delta_{CP}=0$.

  16. Cubic metaplectic forms and theta functions

    CERN Document Server

    Proskurin, Nikolai

    1998-01-01

    The book is an introduction to the theory of cubic metaplectic forms on the 3-dimensional hyperbolic space and the author's research on cubic metaplectic forms on special linear and symplectic groups of rank 2. The topics include: Kubota and Bass-Milnor-Serre homomorphisms, cubic metaplectic Eisenstein series, cubic theta functions, Whittaker functions. A special method is developed and applied to find Fourier coefficients of the Eisenstein series and cubic theta functions. The book is intended for readers, with beginning graduate-level background, interested in further research in the theory of metaplectic forms and in possible applications.

  17. Alpha and beta EEG power reflects L-dopa acute administration in parkinsonian patients

    Directory of Open Access Journals (Sweden)

    Jean-Marc eMelgari

    2014-11-01

    Full Text Available Aim. To evaluate the effect of an acute L-dopa administration on eye-closed resting state electroencephalographic (EEG activity of cognitively preserved Parkinsonian patients. Methods. We examined 24 right-handed patients diagnosed as uncomplicated probable Parkinson’s disease (PD. Each patient underwent UPDRS-part-III evaluation before and 60 minutes after an oral load of L-dopa-methyl-ester/carbidopa 250/25 mg. Resting condition eyes-closed EEG data were recorded both pre- and post L-dopa load. Absolute EEG power values were calculated at each scalp derivation for Delta, Theta, Alpha and Beta frequency bands. UPDRS scores (both global and subscale scores and EEG data (power values of different frequency bands for each scalp derivation were submitted to a statistical analysis to compare Pre e Post L-Dopa conditions. Finally, a correlation analysis was carried out between EEG spectral content and UPDRS scores. Results. Considering EEG power spectral analysis, no statistically significant differences arose on Delta and Theta bands after L-dopa intake. Conversely, Alpha and Beta rhythms significantly increased on centro-parietal scalp derivations, as a function of L-dopa administration. Correlation analysis indicated a significant negative correlation between Beta power increase on centro-parietal areas and UPDRS subscores (Rigidity of arms and Bradykinesia. A minor significant negative correlation was also found between Alpha band increase and resting tremor. Conclusions. Assuming that a significant change in EEG power spectrum after L-dopa intake may be related to dopaminergic mechanisms, our findings are consistent with the hypothesis that dopaminergic defective networks are implicated in cortical oscillatory abnormalities at rest in non-demented PD patients.

  18. Search for the exotic $\\Theta^+$ resonance in the NOMAD experiment

    CERN Document Server

    Samoylov, O; Autiero, D; Baldisseri, Alberto; Baldo-Ceolin, M; Banner, M; Bassompierre, G; Benslama, K; Besson, N; Bird, I; Blumenfeld, B; Bobisut, F; Bouchez, J; Boyd, S; Bueno, A; Bunyatov, S; Camilleri, L L; Cardini, A; Cattaneo, P W; Cavasinni, V; Cervera-Villanueva, A; Challis, R; Chukanov, A; Collazuol, G; Conforto, G; Conta, C; Contalbrigo, M; Cousins, R; Daniels, D; De Santo, A; Degaudenzi, H M; Del Prete, T; Di Lella, L; Dignan, T; Do Couto e Silva, E; Dumarchez, J; Ellis, M; Feldman, G J; Ferrari, R; Ferrère, D; Flaminio, V; Fraternali, M; Gaillard, J M; Gangler, E; Geiser, A; Geppert, D; Gibin, D; Gninenko, S; Godley, A; Gosset, J; Gouanère, M; Grant, A; Graziani, G; Guglielmi, A M; Gómez-Cadenas, J J; Gössling, C; Hagner, C; Hernando, J; Hubbard, D; Hurst, P; Hyett, N; Iacopini, E; Joseph, C; Juget, F; Kent, N; Kirsanov, M; Klimov, O; Kokkonen, J; Kovzelev, A; Krasnoperov, A V; La Rotonda, L; Lacaprara, S; Lachaud, C; Lakic, B; Lanza, A; Laveder, M; Letessier-Selvon, A A; Linssen, L; Ljubicic, A; Long, J; Lupi, A; Lyubushkin, V; Lévy, J M; Marchionni, A; Martelli, F; Mendiburu, J P; Meyer, J P; Mezzetto, M; Mishra, S R; Moorhead, G F; Méchain, X; Naumov, D; Nefedov, Yu; Nguyen-Mau, C; Nédélec, P; Orestano, D; Pastore, F; Peak, L S; Pennacchio, E; Pessard, H; Petti, R; Placci, A; Polesello, G; Pollmann, D; Polyarush, A Yu; Popov, B; Poulsen, C; Rebuffi, L; Rico, J; Riemann, P; Roda, C; Rubbia, André; Salvatore, F; Schahmaneche, K; Schmidt, B; Schmidt, T; Sconza, A; Sevior, M; Sillou, D; Soler, F J P; Sozzi, G; Steele, D; Stiegler, U; Stipcevic, M; Stolarczyk, T; Tareb-Reyes, M; Taylor, G N; Tereshchenko, V V; Toropin, A; Touchard, A M; Tovey, S N; Tran, M T; Tsesmelis, E; Ulrichs, J; Vacavant, L; Valdata-Nappi, M; Valuev, V; Vannucci, F; Varvell, K E; Veltri, M; Vercesi, V; Vidal-Sitjes, G; Vieira, J M; Vinogradova, T; Weber, F V; Weisse, T; Wilson, F F; Winton, L J; Yabsley, B D; Zaccone, Henri; Zuber, K; Zuccon, P

    2007-01-01

    A search for exotic Theta baryon via Theta -> proton +Ks decay mode in the NOMAD muon neutrino DIS data is reported. The special background generation procedure was developed. The proton identification criteria are tuned to maximize the sensitivity to the Theta signal as a function of xF which allows to study the Theta production mechanism. We do not observe any evidence for the Theta state in the NOMAD data. We provide an upper limit on Theta production rate at 90% CL as 2.13 per 1000 of neutrino interactions.

  19. Observational $\\Delta\

    CERN Document Server

    Hernández, Antonio García; Monteiro, Mário J P F G; Suárez, Juan Carlos; Reese, Daniel R; Pascual-Granado, Javier; Garrido, Rafael

    2015-01-01

    Delta Scuti ($\\delta$ Sct) stars are intermediate-mass pulsators, whose intrinsic oscillations have been studied for decades. However, modelling their pulsations remains a real theoretical challenge, thereby even hampering the precise determination of global stellar parameters. In this work, we used space photometry observations of eclipsing binaries with a $\\delta$ Sct component to obtain reliable physical parameters and oscillation frequencies. Using that information, we derived an observational scaling relation between the stellar mean density and a frequency pattern in the oscillation spectrum. This pattern is analogous to the solar-like large separation but in the low order regime. We also show that this relation is independent of the rotation rate. These findings open the possibility of accurately characterizing this type of pulsator and validate the frequency pattern as a new observable for $\\delta$ Sct stars.

  20. Double Chooz and Reactor Theta13 Experiments

    CERN Document Server

    ,

    2016-01-01

    This is a contribution paper from the Double Chooz experiment to the special issue of NPB on neutrino oscillations. The physics and history of the reactor theta13 experiments, as well as Double Chooz experiment and its neutrino oscillation analyses are reviewed.

  1. Hippocampal theta frequency shifts and operant behaviour

    NARCIS (Netherlands)

    Lopes da Silva, F.H.; Kamp, A.

    1. 1. A shift of hippocampal dominant theta frequency to 6 c/sec has been demonstrated in the post-reward period in two dogs, which occurs consistently related in time to a well defined behavioural pattern in the course of an operant conditioning paradigm. 2. 2. The frequency shift was detected and

  2. The Dark Side of $\\theta_{13}$, Leptogenesis and Inflation in Type-I Seesaw

    CERN Document Server

    Huang, Wei-Chih

    2014-01-01

    In the context of the type-I seesaw, it is known that $\\theta_{13}$ is zero and leptogenesis can not be realized if there exists a flavor symmetry resulting in the Tri-Bimaximal neutrino mixing pattern. We propose a simple framework where additional particles, odd under a $Z_2$ symmetry, break the flavor symmetry and the lightest of the $Z_2$ odd particles is the dark matter candidate. As as result, nonzero $\\theta_{13}$, leptogenesis and the correct dark matter density can be accommodated. On the other hand, a $Z_2$ odd scalar can play the role of the inflaton with mass of $10^{13}$ GeV motivated by the recent BICEP2 results. In this situation, the model can "generate" $\\delta_{CP}=-\\pi/2$, preferred by the T2K experiment in the normal hierarchy neutrino mass spectrum.

  3. Measurement of the Neutrino Mixing angle $\\theta_{23}$ in NOvA

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; et al.

    2017-01-20

    This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of $6.05\\times10^{20}$ protons-on-target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal mixing ($\\theta_{23} = \\pi/4$). Assuming the normal mass hierarchy, we find $\\Delta m^2 = (2.67 \\pm 0.11)\\times 10^{-3}$ eV$^2$ and $\\sin^2 \\theta_{23}$ at the two statistically degenerate values $0.404^{+0.030}_{-0.022}$ and $0.624^{+0.022}_{-0.030}$, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6 $\\sigma$ significance.

  4. An $A_4$ realization of inverse seesaw: neutrino masses, $\\theta_{13}$ and leptonic non-unitarity

    CERN Document Server

    Karmakar, Biswajit

    2016-01-01

    We provide an $A_4$ based flavor symmetric scenario to accommodate the inverse seesaw mechanism for explaining light neutrino masses and mixing. We find that the lepton mixing, in particular the tri-bimaximal mixing pattern and its deviation through nonzero $\\theta_{13}$, is originated solely from the flavor structure of the lepton number violating contribution of the neutral lepton mass matrix. Here we discuss in detail how a nonzero value of $\\theta_{13}$ is correlated with the other parameters in the framework and its impact on the Dirac CP phase $\\delta$. We also analyze the non-unitarity effects on lepton mixing matrix and its implication in terms of the lepton flavor violating decays, etc..

  5. Theta-vacuum: Phase Transitions and/or Symmetry Breaking at $\\theta = \\pi$

    CERN Document Server

    Azcoiti, V; Laliena, V

    2003-01-01

    Assuming that a quantum field theory with a $\\theta$-vacuum term in the action shows non-trivial $\\theta$-dependence and provided that some reasonable properties of the probability distribution function of the order parameter hold, we argue that the theory either breaks spontaneously CP at $\\theta = \\pi$ or shows a singular behavior at some critical $\\theta_c$ between 0 and $\\pi$. This result, which applies to any model with a pure imaginary contribution to the euclidean action consisting in a quantized charge coupled to a phase, as QCD, is illustrated with two simple examples; one of them intimately related to Witten's result on SU(N) in the large $N$ limit.

  6. Thalamic Bursts Down-regulate Cortical Theta and Nociceptive Behavior.

    Science.gov (United States)

    LeBlanc, Brian W; Cross, Brent; Smith, Kelsey A; Roach, Catherine; Xia, Jimmy; Chao, Yu-Chieh; Levitt, Joshua; Koyama, Suguru; Moore, Christopher I; Saab, Carl Y

    2017-05-30

    We tested the relation between pain behavior, theta (4-8 Hz) oscillations in somatosensory cortex and burst firing in thalamic neurons in vivo. Optically-induced thalamic bursts attenuated cortical theta and mechanical allodynia. It is proposed that thalamic bursts are an adaptive response to pain that de-synchronizes cortical theta and decreases sensory salience.

  7. The effects of theta transcranial alternating current stimulation (tACS) on fluid intelligence.

    Science.gov (United States)

    Pahor, Anja; Jaušovec, Norbert

    2014-09-01

    The objective of the study was to explore the influence of transcranial alternating current stimulation (tACS) on resting brain activity and on measures of fluid intelligence. Theta tACS was applied to the left parietal and left frontal brain areas of healthy participants after which resting electroencephalogram (EEG) data was recorded. Following sham/active stimulation, the participants solved two tests of fluid intelligence while their EEG was recorded. The results showed that active theta tACS affected spectral power in theta and alpha frequency bands. In addition, active theta tACS improved performance on tests of fluid intelligence. This influence was more pronounced in the group of participants that received stimulation to the left parietal area than in the group of participants that received stimulation to the left frontal area. Left parietal tACS increased performance on the difficult test items of both tests (RAPM and PF&C) whereas left frontal tACS increased performance only on the easy test items of one test (RAPM). The observed behavioral tACS influences were also accompanied by changes in neuroelectric activity. The behavioral and neuroelectric data tentatively support the P-FIT neurobiological model of intelligence.

  8. Genotypic to expression profiling of bovine calcium channel, voltage-dependent, alpha-2/delta subunit 1 gene, and their association with bovine mastitis among Frieswal (HFX Sahiwal) crossbred cattle of Indian origin.

    Science.gov (United States)

    Deb, Rajib; Singh, Umesh; Kumar, Sushil; Kumar, Arun; Singh, Rani; Sengar, Gyanendra; Mann, Sandeep; Sharma, Arjava

    2014-04-01

    Calcium channel, voltage-dependent, alpha-2/delta subunit 1 (CACNA2D1) gene is considered to be an important noncytokine candidate gene influencing mastitis. Scanty of reports are available until today regarding the role play of CACNA2D1 gene on the susceptibility of bovine mastitis. We interrogated the CACNA2D1 G519663A [A>G] SNP by PCR-RFLP among two hundreds Frieswal (HF X Sahiwal) crossbred cattle of Indian origin. Genotypic frequency of AA (51.5, n=101) was comparatively higher than AG (35, n=70) and GG (14.5, n=29). Association of Somatic cell score (SCS) with genotypes revealed that, GG genotypes showing lesser count (less susceptible to mastitis) compare to AA and AG. Relative expression of CACNA2D1 transcript (in milk samples) was significantly higher among GG than AG and AA. Further we have also isolated blood sample from the all groups and PBMCs were cultured from each blood sample as per the standard protocol. They were treated with Calcium channel blocker and the expression level of the CACNA2D1 gene was evaluated by Real Time PCR. Results show that expression level decline in each genotypic group after treatment and expression level of GG are again significantly higher than AA and AG. Thus, it may be concluded that GG genotypic animals are favorable for selecting disease resistant breeds.

  9. On the relation between the effective ferromagnetic resonance linewidth {delta}f{sub eff} and damping parameter {alpha}{sub eff} in ferromagnetic Fe-Co-Hf-N nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Seemann, K. [Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft, Institut fuer Material forschung I, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)], E-mail: klaus.seemann@imf.fzk.de; Leiste, H.; Klever, Ch. [Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft, Institut fuer Material forschung I, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)

    2009-10-15

    Ferromagnetic Fe-Co-Hf-N nanocomposite films were investigated concerning their microstructure-dependent frequency behaviour. To modify the composition, the films were deposited by reactive RF magnetron sputtering by using three different 6 in. targets with various Hf fractions. The films were post-annealed up to 600 deg. C in a static magnetic field to induce an in-plane uniaxial anisotropy and to obtain different crystal sizes. Depending on the annealing temperature, high-frequency losses were investigated by considering the full-width at half-maximum (FWHM) {delta}f{sub eff} of the imaginary part of the frequency-dependent permeability which showed a resonance frequency f{sub FMR} of 2.3 GHz for an in-plane uniaxial anisotropy field H{sub u} of 4 mT. The FWHM in correlation with the damping parameter {alpha}{sub eff} is discussed, e.g., in terms of two-magnon scattering. Damping occurs due to film inhomogeneity in magnetisation and uniaxial anisotropy caused by a magnetocrystalline anisotropy H{sub a} and/or non-magnetic phases. This will result in homogenous or even inhomogeneous resonance line broadening if additional and resonance as well as precession frequencies of independent grains arise.

  10. Indefinite theta series and generalized error functions

    CERN Document Server

    Alexandrov, Sergei; Manschot, Jan; Pioline, Boris

    2016-01-01

    Theta series for lattices with indefinite signature $(n_+,n_-)$ arise in many areas of mathematics including representation theory and enumerative algebraic geometry. Their modular properties are well understood in the Lorentzian case ($n_+=1$), but have remained obscure when $n_+\\geq 2$. Using a higher-dimensional generalization of the usual (complementary) error function, discovered in an independent physics project, we construct the modular completion of a class of `conformal' holomorphic theta series ($n_+=2$). As an application, we determine the modular properties of a generalized Appell-Lerch sum attached to the lattice ${\\operatorname A}_2$, which arose in the study of rank 3 vector bundles on $\\mathbb{P}^2$. The extension of our method to $n_+>2$ is outlined.

  11. Inverse theta functions as quantum modular forms

    CERN Document Server

    Bringmann, Kathrin; Rolen, Larry

    2014-01-01

    In this paper, we consider the Fourier coefficients of a special class of meromorphic Jaocbi forms of negative index. Much recent work has been done on the Fourier coefficients of meromorphic Jacobi forms of positive index, but almost nothing is known for Jacobi forms of negative index. Here we show from two different perspectives that their Fourier coefficients have a simple decomposition in terms of partial theta functions. The first perspective uses the language of Lie super algebras, and the second applies the theory of elliptic functions. In particular, we find a new infinite family of rank-crank type PDEs generalizing the famous example of Atkin and Garvan. We then describe the modularity properties of these coefficients, showing that they are \\emph{mixed quantum modular forms}, along the way determining a new class of quantum modular partial theta functions.

  12. Parvalbumin Interneurons of Hippocampus Tune Population Activity at Theta Frequency.

    Science.gov (United States)

    Amilhon, Bénédicte; Huh, Carey Y L; Manseau, Frédéric; Ducharme, Guillaume; Nichol, Heather; Adamantidis, Antoine; Williams, Sylvain

    2015-06-03

    Hippocampal theta rhythm arises from a combination of recently described intrinsic theta oscillators and inputs from multiple brain areas. Interneurons expressing the markers parvalbumin (PV) and somatostatin (SOM) are leading candidates to participate in intrinsic rhythm generation and principal cell (PC) coordination in distal CA1 and subiculum. We tested their involvement by optogenetically activating and silencing PV or SOM interneurons in an intact hippocampus preparation that preserves intrinsic connections and oscillates spontaneously at theta frequencies. Despite evidence suggesting that SOM interneurons are crucial for theta, optogenetic manipulation of these interneurons modestly influenced theta rhythm. However, SOM interneurons were able to strongly modulate temporoammonic inputs. In contrast, activation of PV interneurons powerfully controlled PC network and rhythm generation optimally at 8 Hz, while continuously silencing them disrupted theta. Our results thus demonstrate a pivotal role of PV but not SOM interneurons for PC synchronization and the emergence of intrinsic hippocampal theta.

  13. Delta robot

    NARCIS (Netherlands)

    Herder, J.L.; Van der Wijk, V.

    2010-01-01

    The invention relates to a delta robot comprising a stationary base (2) and a movable platform (3) that is connected to the base with three chains of links (4,5,6), and comprising a balancing system incorporating at least one pantograph (7) for balancing the robot's center of mass, wherein the at le

  14. Delta robot

    NARCIS (Netherlands)

    Herder, J.L.; Van der Wijk, V.

    2010-01-01

    The invention relates to a delta robot comprising a stationary base (2) and a movable platform (3) that is connected to the base with three chains of links (4,5,6), and comprising a balancing system incorporating at least one pantograph (7) for balancing the robot's center of mass, wherein the at le

  15. A flavour GUT model with theta_13^PMNS = theta_C / sqrt(2)

    CERN Document Server

    Antusch, Stefan; Maurer, Vinzenz; Sluka, Constantin

    2013-01-01

    We propose a supersymmetric SU(5) GUT model with an A_4 family symmetry - including a full flavon- and messenger sector - which realises the relation theta_13^PMNS \\simeq theta_C / sqrt(2). The neutrino sector features tri-bimaximal mixing, and theta_13^PMNS \\simeq theta_C / sqrt(2) emerges from the charged lepton contribution to the PMNS matrix, which in turn is linked to quark mixing via specific GUT relations. These GUT relations arise after GUT symmetry breaking from a novel combination of group theoretical Clebsch-Gordan factors, which in addition to large theta_13^PMNS lead to promising quark lepton mass ratios for all generations of quarks and leptons and to m_s / m_d = 18.95_(-0.24)^(+0.33), in excellent agreement with experimental results. The model also features spontaneous CP violation, with all quark and lepton CP phases determined from family symmetry breaking. We perform a full Markov Chain Monte Carlo fit to the available quark and lepton data, and discuss how the model can be tested by present...

  16. Auditory cortical delta-entrainment interacts with oscillatory power in multiple fronto-parietal networks.

    Science.gov (United States)

    Keitel, Anne; Ince, Robin A A; Gross, Joachim; Kayser, Christoph

    2017-02-15

    The timing of slow auditory cortical activity aligns to the rhythmic fluctuations in speech. This entrainment is considered to be a marker of the prosodic and syllabic encoding of speech, and has been shown to correlate with intelligibility. Yet, whether and how auditory cortical entrainment is influenced by the activity in other speech-relevant areas remains unknown. Using source-localized MEG data, we quantified the dependency of auditory entrainment on the state of oscillatory activity in fronto-parietal regions. We found that delta band entrainment interacted with the oscillatory activity in three distinct networks. First, entrainment in the left anterior superior temporal gyrus (STG) was modulated by beta power in orbitofrontal areas, possibly reflecting predictive top-down modulations of auditory encoding. Second, entrainment in the left Heschl's Gyrus and anterior STG was dependent on alpha power in central areas, in line with the importance of motor structures for phonological analysis. And third, entrainment in the right posterior STG modulated theta power in parietal areas, consistent with the engagement of semantic memory. These results illustrate the topographical network interactions of auditory delta entrainment and reveal distinct cross-frequency mechanisms by which entrainment can interact with different cognitive processes underlying speech perception.

  17. rTMS Induced Tinnitus Relief Is Related to an Increase in Auditory Cortical Alpha Activity

    Science.gov (United States)

    Müller, Nadia; Lorenz, Isabel; Langguth, Berthold; Weisz, Nathan

    2013-01-01

    Chronic tinnitus, the continuous perception of a phantom sound, is a highly prevalent audiological symptom. A promising approach for the treatment of tinnitus is repetitive transcranial magnetic stimulation (rTMS) as this directly affects tinnitus-related brain activity. Several studies indeed show tinnitus relief after rTMS, however effects are moderate and vary strongly across patients. This may be due to a lack of knowledge regarding how rTMS affects oscillatory activity in tinnitus sufferers and which modulations are associated with tinnitus relief. In the present study we examined the effects of five different stimulation protocols (including sham) by measuring tinnitus loudness and tinnitus-related brain activity with Magnetoencephalography before and after rTMS. Changes in oscillatory activity were analysed for the stimulated auditory cortex as well as for the entire brain regarding certain frequency bands of interest (delta, theta, alpha, gamma). In line with the literature the effects of rTMS on tinnitus loudness varied strongly across patients. This variability was also reflected in the rTMS effects on oscillatory activity. Importantly, strong reductions in tinnitus loudness were associated with increases in alpha power in the stimulated auditory cortex, while an unspecific decrease in gamma and alpha power, particularly in left frontal regions, was linked to an increase in tinnitus loudness. The identification of alpha power increase as main correlate for tinnitus reduction sheds further light on the pathophysiology of tinnitus. This will hopefully stimulate the development of more effective therapy approaches. PMID:23390539

  18. Apolipoprotein E and alpha brain rhythms in mild cognitive impairment: a multicentric electroencephalogram study.

    Science.gov (United States)

    Babiloni, Claudio; Benussi, Luisa; Binetti, Giuliano; Cassetta, Emanuele; Dal Forno, Gloria; Del Percio, Claudio; Ferreri, Florinda; Ferri, Raffaele; Frisoni, Giovanni; Ghidoni, Roberta; Miniussi, Carlo; Rodriguez, Guido; Romani, Gian Luca; Squitti, Rosanna; Ventriglia, Maria Carla; Rossini, Paolo M

    2006-02-01

    Relationships between the apolipoprotein E epsilon4 allele and electroencephalographic (EEG) rhythmicity have been demonstrated in Alzheimer's disease (AD) patients but not in the preclinical stage prodromic to it, namely, mild cognitive impairment (MCI). The present multicentric EEG study tested the hypothesis that presence of epsilon4 affects sources of resting EEG rhythms in both MCI and AD subjects. We enrolled 89 MCI subjects (34.8% with epsilon4) and 103 AD patients (50.4% with epsilon4). Resting eyes-closed EEG data were recorded for all subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography. Results showed that amplitude of alpha 1 and 2 sources in occipital, temporal, and limbic areas was lower in subjects carrying the epsilon4 allele than in those not carrying the epsilon4 allele (p neurophysiological phenotype (ie, cortical alpha rhythmicity) in a preclinical AD condition, MCI, in addition to clinically manifest AD. Such a demonstration motivates future genotype-EEG phenotype studies for the early prediction of AD conversion in individual MCI subjects.

  19. Probing the spin-parity of the pentaquark $\\Theta^+$ baryon

    CERN Document Server

    Barmin, V V; Curceanu, C; Davidenko, G V; Guaraldo, C; Kubantsev, M A; Larin, I F; Matveev, V A; Shebanov, V A; Shishov, N N; Sokolov, L I; Tarasov, V V

    2015-01-01

    Using the DIANA data on the charge-exchange reaction K^+n --> pK^0 on a bound neutron, in which the s-channel formation of the pentaquark baryon \\Theta^+(1538) has been observed,we analyze the dependence of the background-subtracted \\Theta^+ --> pK^0 signal on the K^0 emission angle in the pK^0 rest frame. The data are consistent with the angular dependence of a form dW/d\\cos\\Theta_cms ~ (\\cos\\Theta_cms + A)^2 with a positive offset A. This form of the \\cos\\Theta_cms distribution suggests an interference between the \\Theta-mediated p-wave contribution and the nonresonant s-wave contribution to the total amplitude of the charge-exchange reaction. The p-wave nature of the \\Theta-mediated amplitude is consistent with the spin-parity assignment of 1/2^+ for the \\Theta^+ baryon. The selection in \\cos\\Theta_cms based on the observed angular dependence of the \\Theta^+ --> pK^0 signal allows to boost the statistical significance of the signal up to 6.8 standard deviations. \\e

  20. Is \\theta_{13}^{PMNS} correlated with \\theta_{23}^{PMNS} or not?

    CERN Document Server

    Araki, Takeshi

    2013-01-01

    By assuming the Tri-Bi-Maximal mixing at leading order and postulating \\theta_{23} \\simeq 45^\\circ + \\eta\\theta_{13} where \\eta is equal to \\pm 1/\\sqrt{2} or 0, we seek for preferable correction terms to the charged lepton and neutrino mass matrices and discuss their origins. The global fits of neutrino oscillation parameters favor the case of \\eta=\\pm 1/\\sqrt{2}; it corresponds to the relation found by Edy, Frampton and Mastuzaki some years ago in the context of a T^\\prime flavor model. In contrast, the results from the \

  1. Eta Products and Theta Series Identities

    CERN Document Server

    Kohler, Gunter

    2011-01-01

    This monograph deals with products of Dedekind's eta function, with Hecke theta series on quadratic number fields, and with "Eisenstein series." The author brings to the public the large number of identities that have been discovered over the past 20 years, the majority of which have not been published elsewhere. This book will be of interest to graduate students and scholars in the field of number theory and, in particular, modular forms. It is not an introductory text in this field. Nevertheless, some theoretical background material is presented that is important for understanding

  2. Lower trait frontal theta activity in mindfulness meditators

    Directory of Open Access Journals (Sweden)

    Guaraci Ken Tanaka

    2014-09-01

    Full Text Available Acute and long-term effects of mindfulness meditation on theta-band activity are not clear. The aim of this study was to investigate frontal theta differences between long- and short-term mindfulness practitioners before, during, and after mindfulness meditation. Twenty participants were recruited, of which 10 were experienced Buddhist meditators. Despite an acute increase in the theta activity during meditation in both the groups, the meditators showed lower trait frontal theta activity. Therefore, we suggested that this finding is a neural correlate of the expert practitioners’ ability to limit the processing of unnecessary information (e.g., discursive thought and increase the awareness of the essential content of the present experience. In conclusion, acute changes in the theta band throughout meditation did not appear to be a specific correlate of mindfulness but were rather related to the concentration properties of the meditation. Notwithstanding, lower frontal theta activity appeared to be a trait of mindfulness practices.

  3. {theta}-Compactness in L-topological spaces

    Energy Technology Data Exchange (ETDEWEB)

    Hanafy, I.M. [Department of Mathematics, Faculty of Education, Suez Canal University, El-Arish (Egypt)], E-mail: ihanafy@hotmail.com

    2009-12-15

    Recently, El-Naschie has shown that the notion of fuzzy topology may be relevant to quantum particle physics in connection with string theory and e{sup {infinity}} theory. In 2005, Caldas and Jafari have introduced {theta}-compact fuzzy topological spaces. In this paper, the concepts of{theta}-compactness, countable{theta}-compactness and the{theta}-Lindeloef property are introduced and studied in L-topological spaces, where L is a complete de Morgan algebra. They are defined by means of{theta}-openL-sets and their inequalities. They does not rely on the structure of basis lattice L and no distributivity in L is required. They can also be characterized by{theta}-closedL-sets and their inequalities. When L is a completely de Morgan algebra, their many characterizations are presented.

  4. Predictions via large {theta}{sub 13} from cascades

    Energy Technology Data Exchange (ETDEWEB)

    Haba, Naoyuki, E-mail: haba@phys.sci.osaka-u.ac.jp [Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Takahashi, Ryo, E-mail: ryo.takahashi@mpi-hd.mpg.de [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

    2011-08-26

    We investigate a relation among neutrino observables, three mixing angles and two mass squared differences, from a cascade texture of neutrino mass matrix. We show an allowed region of the correlation by use of current data of neutrino oscillation experiments. The relation predicts sharp correlations among neutrino mixing angles as 0.315{<=}sin{sup 2}{theta}{sub 12}{<=}0.332 and 0.480{<=}sin{sup 2}{theta}{sub 23}{<=}0.500 with a large {theta}{sub 13} (0.03theta}{sub 13}<0.28). These magnitudes are modified 0.310{<=}sin{sup 2}{theta}{sub 12}{<=}0.330 and 0.540{<=}sin{sup 2}{theta}{sub 23}{<=}0.560 when the charged lepton mass matrix also has the cascade form.

  5. Artificial theta stimulation impairs encoding of contextual fear memory.

    Directory of Open Access Journals (Sweden)

    Arto Lipponen

    Full Text Available Several experiments have demonstrated an intimate relationship between hippocampal theta rhythm (4-12 Hz and memory. Lesioning the medial septum or fimbria-fornix, a fiber track connecting the hippocampus and the medial septum, abolishes the theta rhythm and results in a severe impairment in declarative memory. To assess whether there is a causal relationship between hippocampal theta and memory formation we investigated whether restoration of hippocampal theta by electrical stimulation during the encoding phase also restores fimbria-fornix lesion induced memory deficit in rats in the fear conditioning paradigm. Male Wistar rats underwent sham or fimbria-fornix lesion operation. Stimulation electrodes were implanted in the ventral hippocampal commissure and recording electrodes in the septal hippocampus. Artificial theta stimulation of 8 Hz was delivered during 3-min free exploration of the test cage in half of the rats before aversive conditioning with three foot shocks during 2 min. Memory was assessed by total freezing time in the same environment 24 h and 28 h after fear conditioning, and in an intervening test session in a different context. As expected, fimbria-fornix lesion impaired fear memory and dramatically attenuated hippocampal theta power. Artificial theta stimulation produced continuous theta oscillations that were almost similar to endogenous theta rhythm in amplitude and frequency. However, contrary to our predictions, artificial theta stimulation impaired conditioned fear response in both sham and fimbria-fornix lesioned animals. These data suggest that restoration of theta oscillation per se is not sufficient to support memory encoding after fimbria-fornix lesion and that universal theta oscillation in the hippocampus with a fixed frequency may actually impair memory.

  6. More on {theta}-compact fuzzy topological spaces

    Energy Technology Data Exchange (ETDEWEB)

    Ekici, Erdal [Department of Mathematics, Canakkale Onsekiz Mart University, Terzioglu Campus, 17020 Canakkale (Turkey)] e-mail: eekici@comu.edu.tr

    2006-03-01

    Recently, El-Naschie has shown that the notion of fuzzy topology may be relevant to quantum particle physics in connection with string theory and {epsilon} {sup {infinity}} theory. In 2005, Caldas and Jafari have introduced {theta}-compact fuzzy topological spaces. The purpose of this paper is to investigate further properties of {theta}-compact fuzzy topological spaces. Moreover, the notion of {theta}-closed fuzzy topological spaces is introduced and properties of it are obtained.

  7. Exotic Theta^+ baryon production induced by photon and pion

    CERN Document Server

    Oh, Y; Lee, S H; Oh, Yongseok; Kim, Hungchong; Lee, Su Houng

    2004-01-01

    We investigate the photoproduction of the $\\Theta^+(1540)$ on a nucleon ($\\gamma n \\to K^- \\Theta^+$, $\\gamma p \\to \\bar{K}^0 \\Theta^+$) and the pion-induced $\\Theta^+$ production reaction on the proton ($\\pi^- p \\to K^- \\Theta^+$). The total cross sections near threshold are estimated by using hadronic models with effective interaction Lagrangians and form factors that preserve gauge-invariance of the electromagnetic current. The photoproduction cross sections are found to be a few hundred nb, with the cross section on the proton being larger than that on the neutron. The pion-induced production cross section is found to be around a few hundred $\\mu$b but sensitive to the $K^* N \\Theta$ coupling whose value is not yet known. We also study the production cross section assuming that the $\\Theta^+$ has negative parity. The cross sections are then found to be much suppressed compared to the case where $\\Theta^+$ has positive parity. Hence, the interpretation of the $\\Theta^+$ as an odd-parity pentaquark state se...

  8. Theta oscillations accompanying concurrent auditory stream segregation.

    Science.gov (United States)

    Tóth, Brigitta; Kocsis, Zsuzsanna; Urbán, Gábor; Winkler, István

    2016-08-01

    The ability to isolate a single sound source among concurrent sources is crucial for veridical auditory perception. The present study investigated the event-related oscillations evoked by complex tones, which could be perceived as a single sound and tonal complexes with cues promoting the perception of two concurrent sounds by inharmonicity, onset asynchrony, and/or perceived source location difference of the components tones. In separate task conditions, participants performed a visual change detection task (visual control), watched a silent movie (passive listening) or reported for each tone whether they perceived one or two concurrent sounds (active listening). In two time windows, the amplitude of theta oscillation was modulated by the presence vs. absence of the cues: 60-350ms/6-8Hz (early) and 350-450ms/4-8Hz (late). The early response appeared both in the passive and the active listening conditions; it did not closely match the task performance; and it had a fronto-central scalp distribution. The late response was only elicited in the active listening condition; it closely matched the task performance; and it had a centro-parietal scalp distribution. The neural processes reflected by these responses are probably involved in the processing of concurrent sound segregation cues, in sound categorization, and response preparation and monitoring. The current results are compatible with the notion that theta oscillations mediate some of the processes involved in concurrent sound segregation.

  9. Theta Oscillations and Reactivity of Hippocampal Stratum Oriens Neurons

    Directory of Open Access Journals (Sweden)

    Valentina F. Kitchigina

    2010-01-01

    Full Text Available The supposition was advanced that the neuronal theta rhythmicity is the key mode of signal selection at the hippocampal level. To address this hypothesis, the experimental data on the responses of putative hippocampal interneurons of the stratum oriens CA1-CA3 to stimulation during enhanced theta rhythm and after its blockade are reviewed. Both a strong increase and a decrease of the natural theta rhythm disturbed the reactions of hippocampal neurons; during theta augmentation, the responses were masked or disappeared, and after theta blockade, they lost the ability to habituate. In both cases, two important events were broken: the resetting of the background activity and the phase-locking of theta cycles to stimulus. These data allow one to suppose that only important stimuli are normally capable to evoke these events and these stimuli are selected for recording. When the response to a significant stimulus occurs, the following theta prevents the responses to other stimuli. This probably protects the hippocampal activity from interference from irrelevant signals. Presumably, the absence of the theta deprives the hippocampus of this protection. During enhanced and persistent theta oscillations, the reset disappeared and theta bursts were generated without stimulus locking. In this state, the system is probably closed and the information cannot be recorded. During the theta blockade, the reset was too long and did not habituate. In this case, the system is open for any signals and the hippocampus loses the ability to select signal. This analysis suggests that information selection in the hippocampus may be performed with the participation of nonpyramidal neurons.

  10. Interstellar absorption along the line of sight to Theta Carinae using Copernicus observations

    Science.gov (United States)

    Allen, M. M.; Jenkins, E. B.; Snow, T. P.

    1992-01-01

    A profile fitting technique is employed to identify the velocities and Doppler b values for H I and H II clouds along the line of sight to Theta Car. Total abundances and depletions for 12 elements, plus column densities for the J = 0 to J = 5 rotational levels of H2 are obtained. Electron densities for both clouds are calculated from the ratios of the fine-structure levels of C II and N II, obtaining 0.08/cu cm and 1.2/cu cm. The fine-structure levels of C I, which led to 120/cu cm, are used to calculate the neutral hydrogen density for the H I region. D I is also present in the data from the Theta Car line of sight, yielding a D/H ratio of 5 x 10 exp -6. Elemental depletions are calculated for the H I region as well. Comparison of the results for Theta Car and those for Zeta Oph and Alpha Vir shows that the absolute depletions are different; however, the relative depletions are remarkably stable for different physical conditions.

  11. Fermion masses and mixing in $\\Delta(27)$ flavour model

    CERN Document Server

    Abbas, Mohammed

    2014-01-01

    An extension of the Standard Model (SM) based on the non-Abelian discrete group $\\Delta(27)$ is considered. The $\\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any flavour changing neural current. We show that the model accounts simultaneously for the observed quark and lepton masses and their mixing. In the quark sector, we find that the up quark mass matrix is flavour diagonal and the Cabbibo-Kobayashi-Maskawa (CKM) mixing matrix arises from down quarks. In the lepton sector, we show that the charged lepton mass matrix is almost diagonal. We also adopt type-I seesaw mechanism to generate neutrino masses. A deviated mixing matrix from tri-bimaximal Maki-Nakagawa-Sakata (MNS), with $\\sin\\theta_{13} \\sim 0.13$ and $\\sin^2 \\theta_{23} \\sim 0.41$, is naturally produced.

  12. A novel EEG for alpha brain state training, neurobiofeedback and behavior change.

    Science.gov (United States)

    Stinson, Bruce; Arthur, David

    2013-08-01

    Mindfulness meditation, with the resulting alpha brain state, is gaining a strong following as an adjunct to health, so too is applying self-affirmation to stimulate behavior change through subconscious re-programming. Until recently the EEG technology needed to demonstrate this has been cumbersome and required specialist training. This paper reports a pilot study using a remote EEG headband, which through a sophisticated algorithm, provides a real-time EEG readout unencumbered by conventional artifacts. In a convenience sample of 13, the difference in brain waves was examined while the subjects were occupied in an 'attention' and an 'alpha mind state' exercise. There was a significant difference in the mean scores for theta, delta, beta and gamma brain waves. Alpha brain waves remained static suggesting an ability of the headset to discriminate a mindful state and to provide real-time, easy to interpret feedback for the facilitator and subject. The findings provide encouragement for research applications in health care activities providing neurobiofeedback to subjects involved in mindfulness behavior change activities.

  13. Spontaneous CP violation in the NJL model at theta = pi

    NARCIS (Netherlands)

    Boer, Daniel; Boomsma, Jorn K.

    2009-01-01

    As is well-known, spontaneous CP-violation in the strong interaction is possible at theta = pi, which is commonly referred to as Dashen's phenomenon. This phenomenon has been studied extensively using chiral Lagrangians. Here the two-flavor NJL model at theta = pi is discussed. It turns out that the

  14. Geometry of theta divisors --- a survey

    CERN Document Server

    Grushevsky, Samuel

    2012-01-01

    We survey the geometry of the theta divisor and discuss various loci of principally polarized abelian varieties (ppav) defined by imposing conditions on its singularities. The loci defined in this way include the (generalized) Andreotti-Mayer loci, but also other geometrically interesting cycles such as the locus of intermediate Jacobians of cubic threefolds. We shall discuss questions concerning the dimension of these cycles as well as the computation of their class in the Chow or the cohomology ring. In addition we consider the class of their closure in suitable toroidal compactifications and describe degeneration techniques which have proven useful. For this we include a discussion of the construction of the universal family of ppav with a level structure and its possible extensions to toroidal compactifications. The paper contains numerous open questions and conjectures.

  15. Superconformal algebras and mock theta functions

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Tohru [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan); Hikami, Kazuhiro [Department of Mathematics, Naruto University of Education, Tokushima 772-8502 (Japan)], E-mail: eguchi@yukawa.kyoto-u.ac.jp, E-mail: hikami@naruto-u.ac.jp

    2009-07-31

    It is known that characters of BPS representations of extended superconformal algebras do not have good modular properties due to extra singular vectors coming from the BPS condition. In order to improve their modular properties we apply the method of Zwegers which has recently been developed to analyze modular properties of mock theta functions. We consider the case of the N=4 superconformal algebra at general levels and obtain the decomposition of characters of BPS representations into a sum of simple Jacobi forms and an infinite series of non-BPS representations. We apply our method to study elliptic genera of hyper-Kaehler manifolds in higher dimensions. In particular, we determine the elliptic genera in the case of complex four dimensions of the Hilbert scheme of points on K3 surfaces K{sup [2]} and complex tori A{sup [[3

  16. A low energy optimization of the CERN-NGS neutrino beam for a $\\theta_{13}$ driven neutrino oscillation search

    CERN Document Server

    Rubbia, André

    2002-01-01

    The possibility to improve the CERN to Gran Sasso neutrino beam performances for $\\theta_{13}$ searches is investigated. We show that by an appropriate optimization of the target and focusing optics of the present CNGS design, we can increase the flux of low energy neutrinos by about a factor 5 compared to the current $\\tau$ optimized focalisation. With the ICARUS 2.35 kton detector at LNGS and in case of negative result, this would allow to improve the limit to $\\sin^22\\theta_{13}$ by an order of magnitude better than the current limit of CHOOZ at $\\Delta m^2\\approx 3\\times 10^{-3} \\rm eV^2$ within 5 years of nominal CNGS running. This is by far the most sensitive setup of the currently approved long-baseline experiments and is competitive with the proposed JHF superbeam.

  17. A PRECISION MEASUREMENT OF THE NEUTRINO MIXING ANGLE THETA (SUB 13) USING REACTOR ANTINEUTRINOS AT DAYA BAY.

    Energy Technology Data Exchange (ETDEWEB)

    KETTELL, S.; ET AL.

    2006-10-16

    This document describes the design of the Daya Bay reactor neutrino experiment. Recent discoveries in neutrino physics have shown that the Standard Model of particle physics is incomplete. The observation of neutrino oscillations has unequivocally demonstrated that the masses of neutrinos are nonzero. The smallness of the neutrino masses (<2 eV) and the two surprisingly large mixing angles measured have thus far provided important clues and constraints to extensions of the Standard Model. The third mixing angle, {delta}{sub 13}, is small and has not yet been determined; the current experimental bound is sin{sup 2} 2{theta}{sub 13} < 0.17 at 90% confidence level (from Chooz) for {Delta}m{sub 31}{sup 2} = 2.5 x 10{sup -3} eV{sup 2}. It is important to measure this angle to provide further insight on how to extend the Standard Model. A precision measurement of sin{sup 2} 2{theta}{sub 13} using nuclear reactors has been recommended by the 2004 APS Multi-divisional Study on the Future of Neutrino Physics as well as a recent Neutrino Scientific Assessment Group (NUSAG) report. We propose to perform a precision measurement of this mixing angle by searching for the disappearance of electron antineutrinos from the nuclear reactor complex in Daya Bay, China. A reactor-based determination of sin{sup 2} 2{theta}{sub 13} will be vital in resolving the neutrino-mass hierarchy and future measurements of CP violation in the lepton sector because this technique cleanly separates {theta}{sub 13} from CP violation and effects of neutrino propagation in the earth. A reactor-based determination of sin{sup 2} 2{theta}{sub 13} will provide important, complementary information to that from long-baseline, accelerator-based experiments. The goal of the Daya Bay experiment is to reach a sensitivity of 0.01 or better in sin{sup 2} 2{theta}{sub 13} at 90% confidence level.

  18. Generation of theta and gamma rhythms in the hippocampus.

    Science.gov (United States)

    Leung, L S

    1998-03-01

    In the behaving rat, theta rhythm was dominant during walking and rapid-eye-movement sleep, while irregular slow activity predominated during immobility and slow-wave sleep. Oscillatory evoked potentials of 20-50 Hz and spontaneous fast (gamma) waves were more prominent during theta compared with non-theta behaviors. The oscillations were simulated by a systems model with recurrent inhibition. The model also predicts a behaviorally dependent inhibition, which was confirmed experimentally using paired-pulse responses. Paired-pulse facilitation (PPF) of the population spikes in CA1 was larger during walking than immobility, mostly mediated by a cholinergic input. Spike responses in vitro were characterized by a relative lack of inhibition or disinhibition compared with the behaving rat. The two-input, two-dipole model of the theta rhythm in CA1 is reviewed. Afferents to the CA1 pyramidal cells are assumed to be rhythmic and consist of atropine-sensitive and atropine-resistant inputs driving the somata and distal dendrites, respectively. The atropine-sensitive theta rhythm was mainly caused by a series of Cl- mediated inhibitory postsynaptic potentials (IPSPs) on pyramidal cells. It is suggested that previous claims of the participation of excitatory postsynaptic potentials (EPSPs) and not IPSPs in the intracellular recordings in vivo were flawed. Single cell recordings in vitro suggested that intrinsic voltage-dependent membrane potential oscillations modulate the response to a theta-frequency driving. Membrane potentials of pyramidal cells in vitro showed resonance in the theta frequency range.

  19. A Grand {Delta}(96) Multiplication-Sign SU(5) Flavour Model

    Energy Technology Data Exchange (ETDEWEB)

    King, Stephen F., E-mail: king@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Luhn, Christoph, E-mail: christoph.luhn@durham.ac.uk [Institute for Particle Physics Phenomenology, University of Durham, Durham, DH1 3LE (United Kingdom); Stuart, Alexander J., E-mail: a.stuart@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)

    2013-02-11

    Recent results from the Daya Bay and RENO reactor experiments have measured the smallest lepton mixing angle and found it to have a value of {theta}{sub 13} Almost-Equal-To 9 Degree-Sign . This result presents a new challenge for the existing paradigms of discrete flavour symmetries which attempt to describe all quark and lepton masses and mixing angles. Here we propose a Supersymmetric Grand Unified Theory of Flavour based on {Delta}(96) Multiplication-Sign SU(5), together with a U(1) Multiplication-Sign Z{sub 3} symmetry, including a full discussion of {Delta}(96) in a convenient basis. The Grand {Delta}(96) Multiplication-Sign SU(5) Flavour Model relates the quark mixing angles and masses in the form of the Gatto-Sartori-Tonin relation and realises the Georgi-Jarlskog mass relations between the charged leptons and down-type quarks. We predict a Bi-trimaximal (not Tri-bimaximal) form of neutrino mixing matrix, which, after including charged lepton corrections with zero phase, leads to the following GUT scale predictions for the atmospheric, solar, and reactor mixing angles: {theta}{sub 23} Almost-Equal-To 36.9 Degree-Sign , {theta}{sub 12} Almost-Equal-To 32.7 Degree-Sign and {theta}{sub 13} Almost-Equal-To 9.6 Degree-Sign , in good agreement with recent global fits, and a zero Dirac CP phase {delta} Almost-Equal-To 0.

  20. Delta III—an evolutionary delta growth

    Science.gov (United States)

    Arvesen, R. J.; Simpson, J. S.

    1996-03-01

    In order to remain competitive in the future and expand the McDonnell Douglas Aerospace market share, MDA has developed an expendable launch system strategy that devices cost-effective launch systems from the Delta II with a growth vehicle configuration called Delta III. The Delta III evolves from the Delta II launch system through development of a larger payload fairing (4-meter diameter), new cryogenically propelled upper stage, new first stage fuel tank, and larger strap-on solid rocket motors. We are developing the Delta III using Integrated Product Development Teams that capitalize on the experience base that has led us to a world record breaking mission success of 49 consecutive Delta II missions. The Delta III first-launch capability is currently planned for the spring of 1998 in support of our first spacecraft customer, Hughes Space and Communications International.

  1.  Gap junction involvement in hippocampal theta rhythm generation

    Directory of Open Access Journals (Sweden)

    Renata Bocian

    2012-10-01

    Full Text Available  Hippocampal theta rhythm is probably the best example of oscillations and synchrony phenomena occurring in neuronal networks of the central nervous system. It is well known that intraneuronal communication via chemical and electrical synapses underlies these oscillatory processes. Despite well-documented knowledge concerning the participation of chemical transmission in production of theta activity, the role of much faster gap junction communication is still not fully understood. This paper provides an overview of current research data concerning the involvement of electrical transmission in generation of the best synchronized EEG pattern recorded from the mammalian brain – theta rhythm.

  2. A Geometrical Model for Non-Zero $\\theta_{13}$

    CERN Document Server

    Chen, Jun-Mou; Li, Xue-Qian

    2011-01-01

    Based on Friedberg and Lee's geometric picture by which the tribimaximal PMNS leptonic mixing matrix is constructed, namely corresponding mixing angles correspond to the geometric angles among the sides of a cube. We suggest that the three realistic mixing angles which slightly deviate from the values determined for the cube, are due to a viable deformation from the perfectly cubic shape. Taking the best fitted results of $\\theta_{12}$ and $\\theta_{23}$ as inputs, we determine the central value of $\\sin^22\\theta_{13}$ should be 0.0238 with a relatively large error tolerance, this value lies in the range of measurement precision of the Daya Bay experiment.

  3. Ghost anomaly and first excited state of sup 8 Be in the sup 9 Be(d,t. alpha. ) sup 4 He reaction at 7 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Szczurek, A.; Bodek, K. (Uniwersytet Jagiellonski, Krakow (Poland). Inst. Fizyki Bochum Univ. (Germany). Inst. fuer Experimentalphysik 1); Jarczyk, L.; Kamys, B.; Strzalkowski, A. (Uniwersytet Jagiellonski, Krakow (Poland). Inst. Fizyki); Krug, J.; Luebcke, W.; Ruehl, H.; Seinke, M.; Stephan, M.; Kamke, D. (Bochum Univ. (Germany). Inst. fuer Experimentalphysik 1)

    1991-08-26

    The three-body reaction {sup 9}Be + d {yields} t + {alpha} + {alpha} has been investigated in kinematically complete experiments at E{sub d} = 7.0 MeV for {theta}{sub t} 100{sup 0}, {theta}{sub {alpha}} = -40{sup 0} and for {theta}{sub t} = 40{sup 0}, {theta}{sub {alpha}} = 72.5{sup 0} to -162.5{sup 0}. The experimental spectra are dominated by sequential processes via intermediate excited states of {sup 8}Be and {sup 7}Li. R-matrix theory was employed to describe the line shape of the first excited state and the ghost anomaly of the ground state of {sup 8}Be. Use was made of the {alpha}{alpha} phase shifts. The best fits were obtained assuming a channel radius of a{sub {alpha}{alpha}} = 4.5 fm. The average intensity of the ghost anomaly for E{sub {alpha}{alpha}} = 0.35-1.0 MeV is 4.3%/MeV ({theta}{sub t} = 40{sup 0}) and 8%/MeV ({theta}{sub t} = 100{sup 0}). For the first excited state of {sup 8}Be we find E{sub x} = 3.00 MeV and {Gamma}{sub x} = 1.23 MeV(FWHM). (orig.).

  4. Age-related changes in rat hippocampal theta rhythms: a difference between type 1 and type 2 theta.

    Science.gov (United States)

    Abe, Y; Toyosawa, K

    1999-05-01

    The age-related changes in two types of theta rhythms recorded from the hippocampus in young (4 months-old), mature (12-13 months-old) and aged (22-25 months-old) rats were investigated. The type 1 theta rhythm was measured from hippocampal EEG recorded from walking rats and the type 2 theta was measured from the EEG induced by reticular pontin oralis nucleus (PON) stimulation in urethane anesthetized rats. The peak frequency and the peak power were detected from power spectra calculated on each theta sample by fast Fourier transformation (FFT). No age-related alteration was observed on the peak frequency of type 1 theta rhythm. However, on type 2 theta rhythm, the peak frequency was decreased in the aged rats compared with the young and the mature rats. The type 2 theta rhythm is cholinergic, and therefore this result suggests that age-related deterioration can be clearly observed in the cholinergic system including the hippocampus in rats.

  5. Theta Oscillations Related to Orientation Recognition in Unattended Condition: A vMMN Study

    Directory of Open Access Journals (Sweden)

    Tianyi Yan

    2017-09-01

    Full Text Available Orientation is one of the important elements of objects that can influence visual processing. In this study, we examined whether changes in orientation could be detected automatically under unattended condition. Visual mismatch negativity (vMMN was used to analyze this processing. In addition, we investigated the underlying neural oscillatory activity. Non-phase-locked spectral power was used to explore the specific frequency related to unexpected changes in orientation. The experiment consisted of standard (0° arrows and deviant (90°/270° arrows stimuli. Compared with standard stimuli, deviant stimuli elicited a larger N170 component (negative wave approximately 170 ms after the stimuli started and a smaller P2 component (positive wave approximately 200 ms after the stimuli started. Furthermore, vMMN was obtained by subtracting the event-related potential (ERP waveforms in response to standard stimuli from those elicited in response to deviant stimuli. According to the time–frequency analysis, deviant stimuli elicited enhanced band power compared with standard stimuli in the delta and theta bands. Compared with previous studies, we concluded that theta activity plays an important role in the generation of the vMMN induced by changes in orientation.

  6. The Delta 2 launcher

    Science.gov (United States)

    Ousley, Gilbert W., Sr.

    1991-12-01

    The utilization of the Delta 2 as the vehicle for launching Aristoteles into its near Sun synchronous orbit is addressed. Delta is NASA's most reliable launch vehicle and is well suited for placing the present Aristoteles spacecraft into a 400 m circular orbit. A summary of some of the Delta 2 flight parameters is presented. Diagrams of a typical Delta 2 two stage separation are included along with statistics on delta reliability and launch plans.

  7. Synthesis of gamma- and delta-lactones from 1alpha-hydroxy-5,6-trans-vitamin D3 by ring-closing metathesis route and their reduction with metal hydrides.

    Science.gov (United States)

    Wojtkielewicz, Agnieszka; Morzycki, Jacek W

    2007-06-01

    New synthetic pathway towards 19-functionalized derivatives of 1alpha-hydroxy-5,6-trans-vitamin D3 was described. Ring-closing metathesis (RCM) of 1alpha-hydroxy-5,6-trans-vitamin D3 1-omega-alkenoates was a key-step. Hydride reduction of resulting lactones led to the new vitamin D3 analogues.

  8. Combinatorics of tenth-order mock theta functions

    Indian Academy of Sciences (India)

    J K SAREEN; M RANA

    2016-10-01

    In this paper, we provide the combinatorial interpretations of two tenth order mock theta functions which appeared in some identities given in Ramanujan’s lost notebook ((1988) Narosa Publishing House, New Delhi).

  9. Measuring theta12 Despite an Uncertain Reactor Neutrino Spectrum

    CERN Document Server

    Ciuffoli, Emilio; Grassi, Marco; Zhang, Xinmin

    2015-01-01

    The recently discovered 5 MeV bump highlights that the uncertainty in the reactor neutrino spectrum is far greater than some theoretical estimates. Medium baseline reactor neutrino experiments will deliver by far the most precise ever measurements of theta12. However, as a result of the bump, such a determination of theta12 using the theoretical spectrum would yield a value of sin^2(2theta12) which is more than 1% higher than the true value. We show that by using recent measurements of the reactor neutrino spectrum the precision of a measurement of theta12 at a medium baseline reactor neutrino experiment can be improved appreciably. We estimate this precision as a function of the 9Li spallation background veto efficiency and dead time.

  10. Matter Mass Generation and Theta Vacuum Dynamical Spontaneous Symmetry Breaking

    CERN Document Server

    Roh, H S

    2001-01-01

    This work proposes a stringent concept of matter mass generation and Theta vacuum in the context of local gauge theory for the strong force under the constraint of the flat universe. The matter mass is generated as the consequence of dynamical spontaneous symmetry breaking (DSSB) of gauge symmetry and discrete symmetries, which is motivated by the parameter Theta representing the surface term. Matter mass generation introduces the typical features of constituent particle mass, dual Meissner effect, and hyperfine structure. The Theta term plays important roles on the DSSB of the gauge group and on the quantization of the matter and vacuum space. The Theta vacuum exhibits the intrinsic principal number and intrinsic angular momentum for intrinsic space quantization in analogy with the extrinsic principal number and extrinsic angular momentum for extrinsic space quantization.

  11. Coherent delta-band oscillations between cortical areas correlate with decision making

    Science.gov (United States)

    Nácher, Verónica; Ledberg, Anders; Deco, Gustavo; Romo, Ranulfo

    2013-01-01

    Coherent oscillations in the theta-to-gamma frequency range have been proposed as a mechanism that coordinates neural activity in large-scale cortical networks in sensory, motor, and cognitive tasks. Whether this mechanism also involves coherent oscillations at delta frequencies (1–4 Hz) is not known. Rather, delta oscillations have been associated with slow-wave sleep. Here, we show coherent oscillations in the delta frequency band between parietal and frontal cortices during the decision-making component of a somatosensory discrimination task. Importantly, the magnitude of this delta-band coherence is modulated by the different decision alternatives. Furthermore, during control conditions not requiring decision making, delta-band coherences are typically much reduced. Our work indicates an important role for synchronous activity in the delta frequency band when large-scale, distant cortical networks coordinate their neural activity during decision making. PMID:23980180

  12. Coherent delta-band oscillations between cortical areas correlate with decision making.

    Science.gov (United States)

    Nácher, Verónica; Ledberg, Anders; Deco, Gustavo; Romo, Ranulfo

    2013-09-10

    Coherent oscillations in the theta-to-gamma frequency range have been proposed as a mechanism that coordinates neural activity in large-scale cortical networks in sensory, motor, and cognitive tasks. Whether this mechanism also involves coherent oscillations at delta frequencies (1-4 Hz) is not known. Rather, delta oscillations have been associated with slow-wave sleep. Here, we show coherent oscillations in the delta frequency band between parietal and frontal cortices during the decision-making component of a somatosensory discrimination task. Importantly, the magnitude of this delta-band coherence is modulated by the different decision alternatives. Furthermore, during control conditions not requiring decision making, delta-band coherences are typically much reduced. Our work indicates an important role for synchronous activity in the delta frequency band when large-scale, distant cortical networks coordinate their neural activity during decision making.

  13. Long-term plasticity is proportional to theta-activity.

    Directory of Open Access Journals (Sweden)

    Marian Tsanov

    Full Text Available BACKGROUND: Theta rhythm in the hippocampal formation is a main feature of exploratory behaviour and is believed to enable the encoding of new spatial information and the modification of synaptic weights. Cyclic changes of dentate gyrus excitability during theta rhythm are related to its function, but whether theta epochs per se are able to alter network properties of dentate gyrus for long time-periods is still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: We used low-frequency stimulation protocols that amplify the power of endogenous theta oscillations, in order to estimate the plasticity effect of endogenous theta oscillations on a population level. We found that stimulation-induced augmentation of the theta rhythm is linked to a subsequent increase of neuronal excitability and decrease of the synaptic response. This EPSP-to-Spike uncoupling is related to an increased postsynaptic spiking on the positive phases of theta frequency oscillations. Parallel increase of the field EPSP slope and the population spike occurs only after concurrent pre- and postsynaptic activation. Furthermore, we observed that long-term potentiation (>24 h occurs in the dentate gyrus of freely behaving adult rats after phasic activity of entorhinal afferents in the theta-frequency range. This plasticity is proportional to the field bursting activity of granule cells during the stimulation, and may comprise a key step in spatial information transfer. Long-term potentiation of the synaptic component occurs only when the afferent stimulus precedes the evoked population burst, and is input-specific. CONCLUSIONS/SIGNIFICANCE: Our data confirm the role of the dentate gyrus in filtering information to the subsequent network during the activated state of the hippocampus.

  14. Hippocampal Theta Dysfunction after Lateral Fluid Percussion Injury

    OpenAIRE

    2010-01-01

    Chronic memory deficits are a major cause of morbidity following traumatic brain injury (TBI). In the rat, the hippocampal theta rhythm is a well-studied correlate of memory function. This study sought to investigate disturbances in hippocampal theta rhythm following lateral fluid percussion injury in the rat. A total of 13 control rats and 12 TBI rats were used. Electrodes were implanted in bilateral hippocampi and an electroencephalogram (EEG) was recorded while the rats explored a new envi...

  15. Genetic dissection of theta rhythm heterogeneity in mice.

    Science.gov (United States)

    Shin, Jonghan; Kim, Daesoo; Bianchi, Riccardo; Wong, Robert K S; Shin, Hee-Sup

    2005-12-13

    Rhythmic oscillatory activities at the theta frequency (4-12 Hz) in the hippocampus have long-attracted attention because they have been implicated in diverse brain functions, including spatial cognition. Although studies based on pharmacology and lesion experiments suggested heterogeneity of these rhythms and their behavioral correlates, controversies are abundant on these issues. Here we show that mice harboring a phospholipase C (PLC)-beta1(-/-) mutation (PLC-beta1(-/-) mice) lack one subset of theta rhythms normally observed during urethane anesthesia, alert immobility, and passive whole-body rotation. In contrast, the other subset of theta rhythms observed during walking or running was intact in these mutant mice. PLC-beta1(-/-) mice also have somewhat disrupted theta activity during paradoxical sleep but do have an atropine-resistant component of theta rhythm. In addition, carbachol-induced oscillations were obliterated in hippocampal slices of PLC-beta1(-/-) mice. Interestingly, PLC-beta1(-/-) mice showed deficits in a hidden platform version of the Morris water maze yet performed well in motor coordination tests and a visual platform version of the Morris water maze. The results genetically define the existence of at least two subtypes of theta rhythms and reveal their association with different behaviors.

  16. Alpha Thalassemia

    Science.gov (United States)

    Alpha Thalassemia Physicians often mistake alpha thalassemia trait for iron deficiency anemia and incorrectly prescribe iron supplements that have no effect 1 on the anemia. αα αα Normal alpha ...

  17. Fatty acid homeostasis and induction of lipid regulatory genes in skeletal muscles of peroxisome proliferator-activated receptor (PPAR) alpha knock-out mice. Evidence for compensatory regulation by PPAR delta

    National Research Council Canada - National Science Library

    Muoio, Deborah M; MacLean, Paul S; Lang, David B; Li, Shi; Houmard, Joseph A; Way, James M; Winegar, Deborah A; Corton, J Christopher; Dohm, G Lynis; Kraus, William E

    2002-01-01

    Ablation of peroxisome proliferator activated receptor (PPAR) alpha, a lipid-activated transcription factor that regulates expression of beta-oxidative genes, results in profound metabolic abnormalities in liver and heart...

  18. Studies on the metabolism of the Delta9-tetrahydrocannabinol precursor Delta9-tetrahydrocannabinolic acid A (Delta9-THCA-A) in rat using LC-MS/MS, LC-QTOF MS and GC-MS techniques.

    Science.gov (United States)

    Jung, Julia; Meyer, Markus R; Maurer, Hans H; Neusüss, Christian; Weinmann, Wolfgang; Auwärter, Volker

    2009-10-01

    In Cannabis sativa, Delta9-Tetrahydrocannabinolic acid-A (Delta9-THCA-A) is the non-psychoactive precursor of Delta9-tetrahydrocannabinol (Delta9-THC). In fresh plant material, about 90% of the total Delta9-THC is available as Delta9-THCA-A. When heated (smoked or baked), Delta9-THCA-A is only partially converted to Delta9-THC and therefore, Delta9-THCA-A can be detected in serum and urine of cannabis consumers. The aim of the presented study was to identify the metabolites of Delta9-THCA-A and to examine particularly whether oral intake of Delta9-THCA-A leads to in vivo formation of Delta9-THC in a rat model. After oral application of pure Delta9-THCA-A to rats (15 mg/kg body mass), urine samples were collected and metabolites were isolated and identified by liquid chromatography-mass spectrometry (LC-MS), liquid chromatography-tandem mass spectrometry (LC-MS/MS) and high resolution LC-MS using time of flight-mass spectrometry (TOF-MS) for accurate mass measurement. For detection of Delta9-THC and its metabolites, urine extracts were analyzed by gas chromatography-mass spectrometry (GC-MS). The identified metabolites show that Delta9-THCA-A undergoes a hydroxylation in position 11 to 11-hydroxy-Delta9-tetrahydrocannabinolic acid-A (11-OH-Delta9-THCA-A), which is further oxidized via the intermediate aldehyde 11-oxo-Delta9-THCA-A to 11-nor-9-carboxy-Delta9-tetrahydrocannabinolic acid-A (Delta9-THCA-A-COOH). Glucuronides of the parent compound and both main metabolites were identified in the rat urine as well. Furthermore, Delta9-THCA-A undergoes hydroxylation in position 8 to 8-alpha- and 8-beta-hydroxy-Delta9-tetrahydrocannabinolic acid-A, respectively, (8alpha-Hydroxy-Delta9-THCA-A and 8beta-Hydroxy-Delta9-THCA-A, respectively) followed by dehydration. Both monohydroxylated metabolites were further oxidized to their bishydroxylated forms. Several glucuronidation conjugates of these metabolites were identified. In vivo conversion of Delta9-THCA-A to Delta9-THC was

  19. Delta Plaza kohvik = Delta Plaza cafe

    Index Scriptorium Estoniae

    2010-01-01

    Tallinnas Pärnu mnt 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Tiiu Truusi tähtsamate tööde loetelu. Büroohoone Delta Plaza arhitektid Marika Lõoke ja Jüri Okas (AB J. Okas & M. Lõoke)

  20. Delta Plaza kohvik = Delta Plaza cafe

    Index Scriptorium Estoniae

    2010-01-01

    Tallinnas Pärnu mnt 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Tiiu Truusi tähtsamate tööde loetelu. Büroohoone Delta Plaza arhitektid Marika Lõoke ja Jüri Okas (AB J. Okas & M. Lõoke)

  1. Precise Measurement of the Neutrino Mixing Parameter \\theta_{23} from Muon Neutrino Disappearance in an Off-axis Beam

    CERN Document Server

    Abe, K; Aihara, H; Akiri, T; Andreopoulos, C; Aoki, S; Ariga, A; Ariga, T; Assylbekov, S; Autiero, D; Barbi, M; Barker, G J; Barr, G; Bass, M; Batkiewicz, M; Bay, F; Bentham, S W; Berardi, V; Berger, B E; Berkman, S; Bertram, I; Bhadra, S; Blaszczyk, F d M; Blondel, A; Bojechko, C; Bordoni, S; Boyd, S B; Brailsford, D; Bravar, A; Bronner, C; Buchanan, N; Calland, R G; Caravaca, J; Cartwright, S L; Castillo, R; Catanesi, M G; Cervera, A; Cherdack, D; Christodoulou, G; Clifton, A; Coleman, J; Coleman, S J; Collazuol, G; Connolly, K; Cremonesi, L; Dabrowska, A; Danko, I; Das, R; Davis, S; de, P; De, G; Dealtry, T; Dennis, S R; Densham, C; Di, F; Di, S; Drapier, O; Duboyski, T; Duffy, K; Dufour, F; Dumarchez, J; Dytman, S; Dziewiecki, M; Emery, S; Ereditato, A; Escudero, L; Finch, A J; Floetotto, L; Friend, M; Fujii, Y; Fukuda, Y; Furmanski, A P; Galymov, V; Giffin, S; Giganti, C; Gilje, K; Goeldi, D; Golan, T; Gonin, M; Grant, N; Gudin, D; Hadley, D R; Haesler, A; Haigh, M D; Hamilton, P; Hansen, D; Hara, T; Hartz, M; Hasegawa, T; Hastings, N C; Hayato, Y; Hearty, C; Helmer, R L; Hierholzer, M; Hignight, J; Hillairet, A; Himmel, A; Hiraki, T; Hirota, S; Holeczek, J; Horikawa, S; Huang, K; Ichikawa, A K; Ieki, K; Ieva, M; Ikeda, M; Imber, J; Insler, J; Irvine, T J; Ishida, T; Ishii, T; Ives, S J; Iwai, E; Iyogi, K; Izmaylov, A; Jacob, A; Jamieson, B; Johnson, R A; Jo, J H; Jonsson, P; Jung, C K; Kabirnezhad, M; Kaboth, A C; Kajita, T; Kakuno, H; Kameda, J; Kanazawa, Y; Karlen, D; Karpikov, I; Kearns, E; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kikawa, T; Kilinski, A; Kim, J; Kisiel, J; Kitching, P; Kobayashi, T; Koch, L; Kolaceke, A; Konaka, A; Kormos, L L; Korzenev, A; Koseki, K; Koshio, Y; Kreslo, I; Kropp, W; Kubo, H; Kudenko, Y; Kumaratunga, S; Kurjata, R; Kutter, T; Lagoda, J; Laihem, K; Lamont, I; Laveder, M; Lawe, M; Lazos, M; Lee, K P; Lindner, T; Lister, C; Litchfield, R P; Longhin, A; Ludovici, L; Macaire, M; Magaletti, L; Mahn, K; Malek, M; Manly, S; Marino, A D; Marteau, J; Martin, J F; Maruyama, T; Marzec, J; Mathie, E L; Matveev, V; Mavrokoridis, K; Mazzucato, E; McCarthy, M; McCauley, N; McFarland, K S; McGrew, C; Metelko, C; Mezzetto, M; Mijakowski, P; Miller, C A; Minamino, A; Mineev, O; Mine, S; Missert, A; Miura, M; Monfregola, L; Moriyama, S; Mueller, Th A; Murakami, A; Murdoch, M; Murphy, S; Myslik, J; Nagasaki, T; Nakadaira, T; Nakahata, M; Nakai, T; Nakamura, K; Nakayama, S; Nakaya, T; Nakayoshi, K; Naples, D; Nielsen, C; Nirkko, M; Nishikawa, K; Nishimura, Y; O'Keeffe, H M; Ohta, R; Okumura, K; Okusawa, T; Oryszczak, W; Oser, S M; Owen, R A; Oyama, Y; Palladino, V; Paolone, V; Payne, D; Perevozchikov, O; Perkin, J D; Petrov, Y; Pickard, L; Pinzon, E S; Pistillo, C; Plonski, P; Poplawska, E; Popov, B; Posiadala, M; Poutissou, J -M; Poutissou, R; Przewlocki, P; Quilain, B; Radicioni, E; Ratoff, P N; Ravonel, M; Rayner, M A M; Redij, A; Reeves, M; Reinherz-Aronis, E; Retiere, F; Robert, A; Rodrigues, P A; Rojas, P; Rondio, E; Roth, S; Rubbia, A; Ruterbories, D; Sacco, R; Sakashita, K; Sánchez, F; Sato, F; Scantamburlo, E; Scholberg, K; Schoppmann, S; Schwehr, J; Scott, M; Seiya, Y; Sekiguchi, T; Sekiya, H; Sgalaberna, D; Shiozawa, M; Short, S; Shustrov, Y; Sinclair, P; Smith, B; Smith, R J; Smy, M; Sobczyk, J T; Sobel, H; Sorel, M; Southwell, L; Stamoulis, P; Steinmann, J; Still, B; Suda, Y; Suzuki, A; Suzuki, K; Suzuki, S Y; Suzuki, Y; Szeglowski, T; Tacik, R; Tada, M; Takahashi, S; Takeda, A; Takeuchi, Y; Tanaka, H K; Tanaka, H A; Tanaka, M M; Terhorst, D; Terri, R; Thompson, L F; Thorley, A; Tobayama, S; Toki, W; Tomura, T; Totsuka, Y; Touramanis, C; Tsukamoto, T; Tzanov, M; Uchida, Y; Ueno, K; Vacheret, A; Vagins, M; Vasseur, G; Wachala, T; Waldron, A V; Walter, C W; Wark, D; Wascko, M O; Weber, A; Wendell, R; Wilkes, R J; Wilking, M J; Wilkinson, C; Williamson, Z; Wilson, J R; Wilson, R J; Wongjirad, T; Yamada, Y; Yamamoto, K; Yanagisawa, C; Yen, S; Yershov, N; Yokoyama, M; Yuan, T; Yu, M; Zalewska, A; Zalipska, J; Zambelli, L; Zaremba, K; Ziembicki, M; Zimmerman, E D; Zito, M; Zmuda, J

    2014-01-01

    New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter theta_{23}. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57 x 10^{20} protons on target, T2K has fit the energy-dependent nu_mu oscillation probability to determine oscillation parameters. Marginalizing over the values of other oscillation parameters yields sin^2 (theta_{23}) = 0.514 +0.055/-0.056 (0.511 +- 0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Delta m^2_{32} = 2.51 +- 0.10 x 10^{-3} eV^2/c^4 (inverted hierarchy: Delta m^2_{13} = 2.48 +- 0.10 x 10^{-3} eV^2/c^4). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

  2. Quantum modular forms, mock modular forms, and partial theta functions

    Science.gov (United States)

    Kimport, Susanna

    Defined by Zagier in 2010, quantum modular forms have been the subject of an explosion of recent research. Many of these results are aimed at discovering examples of these functions, which are defined on the rational numbers and have "nice" modularity properties. Though the subject is in its early stages, numerous results (including Zagier's original examples) show these objects naturally arising from many areas of mathematics as limits of other modular-like functions. One such family of examples is due to Folsom, Ono, and Rhoades, who connected these new objects to partial theta functions (introduced by Rogers in 1917) and mock modular forms (about which there is a rich theory, whose origins date back to Ramanujan in 1920). In this thesis, we build off of the work of Folsom, Ono, and Rhoades by providing an infinite family of quantum modular forms of arbitrary positive half-integral weight. Further, this family of quantum modular forms "glues" mock modular forms to partial theta functions and is constructed from a so-called "universal" mock theta function by extending a method of Eichler and Zagier (originally defined for holomorphic Jacobi forms) into a non-holomorphic setting. In addition to the infinite family, we explore the weight 1/2 and 3/2 functions in more depth. For both of these weights, we are able to explicitly write down the quantum modular form, as well as the corresponding "errors to modularity," which can be shown to be Mordell integrals of specific theta functions and, as a consequence, are real-analytic functions. Finally, we turn our attention to the partial theta functions associated with these low weight examples. Berndt and Kim provide asymptotic expansions for a certain class of partial theta functions as q approaches 1 radially within the unit disk. Here, we extend this work to not only obtain asymptotic expansions for this class of functions as q approaches any root of unity, but also for a certain class of derivatives of these functions

  3. Harnessing the power of theta: natural manipulations of cognitive performance during hippocampal theta-contingent eyeblink conditioning

    Science.gov (United States)

    Hoffmann, Loren C.; Cicchese, Joseph J.; Berry, Stephen D.

    2015-01-01

    Neurobiological oscillations are regarded as essential to normal information processing, including coordination and timing of cells and assemblies within structures as well as in long feedback loops of distributed neural systems. The hippocampal theta rhythm is a 3–12 Hz oscillatory potential observed during cognitive processes ranging from spatial navigation to associative learning. The lower range, 3–7 Hz, can occur during immobility and depends upon the integrity of cholinergic forebrain systems. Several studies have shown that the amount of pre-training theta in the rabbit strongly predicts the acquisition rate of classical eyeblink conditioning and that impairment of this system substantially slows the rate of learning. Our lab has used a brain-computer interface (BCI) that delivers eyeblink conditioning trials contingent upon the explicit presence or absence of hippocampal theta. A behavioral benefit of theta-contingent training has been demonstrated in both delay and trace forms of the paradigm with a two- to four-fold increase in learning speed. This behavioral effect is accompanied by enhanced amplitude and synchrony of hippocampal local field potential (LFP)s, multi-unit excitation, and single-unit response patterns that depend on theta state. Additionally, training in the presence of hippocampal theta has led to increases in the salience of tone-induced unit firing patterns in the medial prefrontal cortex, followed by persistent multi-unit activity during the trace interval. In cerebellum, rhythmicity and precise synchrony of stimulus time-locked LFPs with those of hippocampus occur preferentially under the theta condition. Here we review these findings, integrate them into current models of hippocampal-dependent learning and suggest how improvement in our understanding of neurobiological oscillations is critical for theories of medial temporal lobe processes underlying intact and pathological learning. PMID:25918501

  4. Amyloid Beta Peptides Differentially Affect Hippocampal Theta Rhythms In Vitro

    Directory of Open Access Journals (Sweden)

    Armando I. Gutiérrez-Lerma

    2013-01-01

    Full Text Available Soluble amyloid beta peptide (Aβ is responsible for the early cognitive dysfunction observed in Alzheimer's disease. Both cholinergically and glutamatergically induced hippocampal theta rhythms are related to learning and memory, spatial navigation, and spatial memory. However, these two types of theta rhythms are not identical; they are associated with different behaviors and can be differentially modulated by diverse experimental conditions. Therefore, in this study, we aimed to investigate whether or not application of soluble Aβ alters the two types of theta frequency oscillatory network activity generated in rat hippocampal slices by application of the cholinergic and glutamatergic agonists carbachol or DHPG, respectively. Due to previous evidence that oscillatory activity can be differentially affected by different Aβ peptides, we also compared Aβ25−35 and Aβ1−42 for their effects on theta rhythms in vitro at similar concentrations (0.5 to 1.0 μM. We found that Aβ25−35 reduces, with less potency than Aβ1−42, carbachol-induced population theta oscillatory activity. In contrast, DHPG-induced oscillatory activity was not affected by a high concentration of Aβ25−35 but was reduced by Aβ1−42. Our results support the idea that different amyloid peptides might alter specific cellular mechanisms related to the generation of specific neuronal network activities, instead of exerting a generalized inhibitory effect on neuronal network function.

  5. Breaking Tri-bimaximal Mixing and Large $\\theta_{13}$

    CERN Document Server

    Shimizu, Yusuke; Watanabe, Atsushi

    2011-01-01

    The long baseline neutrino experiment, T2K, and the reactor experiment, Double Chooz will soon present new data. If we expect $\\sin\\theta_{13}$ to be 0.1-0.2, which is close to the present experimental upper bound, we should not persist in the paradigm of the tri-bimaximal mixing. We discuss the breaking the tri-bimaximal mixing by adding a simple mass matrix, which could be derived from some non-Abelian discrete symmetries. It is found that $\\sin\\theta_{13}=0.1-0.2$ is expected in our model independent analysis of the generalized mass matrix. On the other hand, $\\sin^2\\theta_{23}$ and $\\sin^2\\theta_{12}$ are expected to be not far from 1/2 and 1/3, respectively. As a typical example, we also discuss the $A_4$ flavor model with the 1 and 1' flavons, which break the tri-bimaximal mixing considerably. In this modified version of the Altarelli and Feruglio model, $\\sin\\theta_{13}$ is predicted to be around 0.15 in the case of the normal hierarchical neutrino masses $m_3\\gg m_2, m_1$, and 0.2 in the case of the i...

  6. On the pullback of an arithmetic theta function

    CERN Document Server

    Kudla, Stephen

    2011-01-01

    In this paper, we consider the relation between the simplest types of arithmetic theta series, those associated to the cycles on the moduli space $\\Cal C$ of elliptic curves with CM by the ring of integers $\\OK$ in an imaginary quadratic field $\\kay$, on the one hand, and those associated to cycles on the arithmetic surface $\\M$ parametrizing 2-dimensional abelian varieties with an action of the maximal order $O_B$ in an indefinite quaternion algebra $B$ over $\\Q$, on the other. We show that the arithmetic degree of the pullback to $Cal C$ of the arithmetic theta function of weight 3/2 valued in $\\hat CH^1(\\M)$ can be expressed as a linear combination of arithmetic theta functions of weight 1 for $\\Cal C$ and unary theta series. This identity can be viewed as an arithmetic seesaw identity. In addition, we show that the arithmetic theta series of weight 1 coincide with the central derivative of certain incoherent Eisenstein series for SL(2)/Q, generalizing earlier joint work with M. Rapoport for the case of a ...

  7. Type III von Neumann Algebras associated with $\\O_\\theta$

    CERN Document Server

    Yang, Dilian

    2011-01-01

    Let $\\Fth$ be a 2 graph generated by $m$ blue edges and $n$ red edges, and $\\omega$ be the distinguished faithful state associated with its graph C*-algebra $\\O_\\theta$. In this paper, we characterize the factorness of the von Neumann algebra $\\pi_\\omega(\\O_\\theta)"$ induced from the GNS representation of $\\omega$ under a certain condition. Moreover, when $\\pi_\\omega(\\O_\\theta)"$ is a factor, then it is of type III$_{m^{-\\frac{1}{b}}}$ (or III$_{n^{-\\frac{1}{a}}}$) if $\\frac{\\ln m}{\\ln n}\\in\\bQ$, where $a,b\\in\\bN$ with $\\gcd(a,b)=1$ satisfy $m^a=n^b$, and of type III$_1$ if $\\frac{\\ln m}{\\ln n}\

  8. Clustering of Ly alpha emitters at z approximate to 4.5

    NARCIS (Netherlands)

    Kovac, Katarina; Somerville, Rachel S.; Rhoads, James E.; Malhotra, Sangeeta; Wang, JunXian

    2007-01-01

    We present the clustering properties of 151 Ly alpha-emitting galaxies at z approximate to 4.5 selected from the Large Area Lyman Alpha (LALA) survey. Our catalog covers an area of 36'; 36' observed with five narrowband filters. We assume that the angular correlation function w(theta) is well repres

  9. Clustering of Ly alpha emitters at z approximate to 4.5

    NARCIS (Netherlands)

    Kovac, Katarina; Somerville, Rachel S.; Rhoads, James E.; Malhotra, Sangeeta; Wang, JunXian

    2007-01-01

    We present the clustering properties of 151 Ly alpha-emitting galaxies at z approximate to 4.5 selected from the Large Area Lyman Alpha (LALA) survey. Our catalog covers an area of 36'; 36' observed with five narrowband filters. We assume that the angular correlation function w(theta) is well

  10. Predicting {theta}{sub 13} and the neutrino mass scale from quark lepton mass hierarchies

    Energy Technology Data Exchange (ETDEWEB)

    Buchmueller, W.; Domcke, V.; Schmitz, K.

    2011-11-15

    Flavour symmetries of Froggatt-Nielsen type can naturally reconcile the large quark and charged lepton mass hierarchies and the small quark mixing angles with the observed small neutrino mass hierarchies and their large mixing angles. We point out that such a flavour structure, together with the measured neutrino mass squared differences and mixing angles, strongly constrains yet undetermined parameters of the neutrino sector. Treating unknown O(1) parameters as random variables, we obtain surprisingly accurate predictions for the smallest mixing angle, sin{sup 2}2{theta}{sub 13}=0.07{sup +0.11}{sub -0.05}, the smallest neutrino mass, m{sub 1}=2.5{sup +1.7}{sub -1.6} x 10{sup -3} eV, and one Majorana phase, {alpha}{sub 21}/{pi}=1.0{sup +0.2}{sub -0.2}. (orig.)

  11. Tri-Permuting Mixing Matrix and predictions for theta_13

    CERN Document Server

    Bazzocchi, F

    2011-01-01

    We introduce a new texture for neutrino mixing named Tri-Permuting (TP) mixing matrix. This pattern is characterized by maximal solar and atmospheric angles and by a large reactor angle satisfying sin(theta_13)=1/3. The correct lepton mixing matrix is obtained when combining the charged lepton mixing matrix with the neutrino one. In this way we get new predictions for theta_13 with respect to those obtained by the well studied TBM or BM mixing patterns. We present a specific model that gives rise to TP mixing in the neutrino sector as well as the required corrections from the charged lepton one.

  12. Precise measurement of theta_13 at Daya Bay

    CERN Document Server

    Chu, M -C

    2008-01-01

    The Daya Bay Reactor Neutrino Experiment is designed to determine the yet unknown neutrino mixing angle theta_13 by measuring the disappearance of electron antineutrinos from several nuclear reactor cores, using multiple underground detectors at different baselines to minimize systematic errors and to suppress the cosmogenic background. The civil construction has begun since October 2007, enabling first commissioning data in 2009, and full data taking will begin in late 2010. The planned sensitivity in sin^2 (2theta_13) of better than 0.01 at 90% CL will be achieved in three years of data-taking. I will present an overview and current status of the experiment.

  13. Double Chooz: Searching for theta13 with reactor neutrinos

    CERN Document Server

    Novella, P

    2011-01-01

    The Double Chooz experiment is meant to search for the neutrino mixing angle theta13 taking advantage of the neutrinos generated at the nuclear power plant of Chooz. Double Chooz relies on neutrino flux measurements at two different locations, the so-called far and near detectors, although the first phase runs only with the far detector. The commissioning of the far detector started in January 2011 and first results improving the current limit on theta13 are expected by the summer 2011. The status of the Double Chooz experiment is presented.

  14. A Grand Delta(96) x SU(5) Flavour Model

    CERN Document Server

    King, Stephen F; Stuart, Alexander J

    2012-01-01

    Recent results from the Daya Bay and RENO reactor experiments have measured the smallest lepton mixing angle and found it to have a value of theta_13 approximately 9 degrees. This result presents a new challenge for the existing paradigms of discrete flavour symmetries which attempt to describe all quark and lepton masses and mixing angles. Here we propose a Supersymmetric Grand Unified Theory of Flavour based on Delta(96) x SU(5), together with a U(1) x Z3 symmetry, including a full discussion of Delta(96) in a convenient basis. The Grand Delta(96) x SU(5) Flavour Model relates the quark mixing angles and masses in the form of the Gatto-Sartori-Tonin relation and realises the Georgi-Jarlskog mass relations between the charged leptons and down-type quarks. We predict a Bi-trimaximal (not Tri-bimaximal) form of neutrino mixing matrix, which, after including charged lepton corrections with zero phase, leads to the following GUT scale predictions for the atmospheric, solar, and reactor mixing angles: theta_23=36...

  15. Combined transcranial alternating current stimulation and continuous theta burst stimulation: a novel approach for neuroplasticity induction.

    Science.gov (United States)

    Goldsworthy, Mitchell R; Vallence, Ann-Maree; Yang, Ruiting; Pitcher, Julia B; Ridding, Michael C

    2016-02-01

    Non-invasive brain stimulation can induce functionally relevant plasticity in the human cortex, making it potentially useful as a therapeutic tool. However, the induced changes are highly variable between individuals, potentially limiting research and clinical utility. One factor that might contribute to this variability is the level of cortical inhibition at the time of stimulation. The alpha rhythm (~ 8-13 Hz) recorded with electroencephalography (EEG) is thought to reflect pulsatile cortical inhibition; therefore, targeting non-invasive brain stimulation to particular phases of the alpha rhythm may provide an approach to enhance plasticity induction. Transcranial alternating current stimulation (tACS) has been shown to entrain cortical oscillations in a frequency-specific manner. We investigated whether the neuroplastic response to continuous theta burst stimulation (cTBS) was enhanced by timing bursts of stimuli to the peak or the trough of a tACS-imposed alpha rhythm. While motor evoked potentials (MEPs) were unaffected when cTBS was applied in-phase with the peak of the tACS-imposed oscillation, MEP depression was enhanced when cTBS was applied in-phase with the trough. This enhanced MEP depression was dependent on the individual peak frequency of the endogenous alpha rhythm recorded with EEG prior to stimulation, and was strongest in those participants classified as non-responders to standard cTBS. These findings suggest that tACS may be used in combination with cTBS to enhance the plasticity response. Furthermore, the peak frequency of endogenous alpha, as measured with EEG, may be used as a simple marker to pre-select those individuals likely to benefit from this approach.

  16. Motor Cortex Theta and Gamma Architecture in Young Adult APPswePS1dE9 Alzheimer Mice

    Science.gov (United States)

    Lundt, Andreas; Wormuth, Carola; Ginde, Varun Raj; Müller, Ralf; Henseler, Christina; Broich, Karl; Xie, Kan; Haenisch, Britta; Ehninger, Dan; Weiergräber, Marco

    2017-01-01

    Alzheimer’s disease (AD) is a multifactorial disorder leading to progressive memory loss and eventually death. In this study, an APPswePS1dE9 AD mouse model has been analyzed for motor cortex theta, beta and gamma frequency alterations using computerized 3D stereotaxic electrode positioning and implantable video-EEG radiotelemetry to perform long-term M1 recordings from both genders considering age, circadian rhythm and activity status of experimental animals. We previously demonstrated that APPswePS1dE9 mice exibit complex alterations in hippocampal frequency power and another recent investigation reported a global increase of alpha, beta and gamma power in APPswePS1dE9 in females of 16–17 weeks of age. In this cortical study in APPswePS1dE9 mice we did not observe any changes in theta, beta and particularly gamma power in both genders at the age of 14, 15, 18 and 19 weeks. Importantly, no activity dependence of theta, beta and gamma activity could be detected. These findings clearly point to the fact that EEG activity, particularly gamma power exhibits developmental changes and spatial distinctiveness in the APPswePS1dE9 mouse model of Alzheimer’s disease. PMID:28072877

  17. Crystalline anhydrous {alpha},{alpha}-trehalose (polymorph {beta}) and crystalline dihydrate {alpha},{alpha}-trehalose: A calorimetric study

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Susana S. [Centro de Quimica Estrutural, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: susanapinto@ist.utl.pt; Diogo, Herminio P. [Centro de Quimica Estrutural, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: hdiogo@ist.utl.pt; Moura-Ramos, Joaquim J. [Centro de Quimica-Fisica Molecular, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: mouraramos@ist.utl.pt

    2006-09-15

    The mean values of the standard massic energy of combustion of crystalline anhydrous {alpha},{alpha}-trehalose (C{sub 12}H{sub 22}O{sub 11}, polymorph {beta}) and crystalline dihydrate {alpha},{alpha}-trehalose (C{sub 12}H{sub 26}O{sub 13}) measured by static-bomb combustion calorimetry in oxygen, at the temperature T=298.15K, are {delta}{sub c}u{sup o}=-(16434.05+/-4.50)J.g{sup -1} and {delta}{sub c}u{sup o}=-(14816.05+/-3.52)J.g{sup -1}, respectively. The standard (p{sup o}=0.1MPa) molar enthalpy of formation of these compounds were derived from the corresponding standard molar enthalpies of combustion, respectively, {delta}{sub f}H{sub m}{sup o} (C{sub 12}H{sub 22}O{sub 11},cr)=-(2240.9+/-3.9)kJ.mol{sup -1}, and {delta}{sub f}H{sub m}{sup o} (C{sub 12}H{sub 26}O{sub 13},cr)=-(2832.6+/-3.6)kJ.mol{sup -1}. The values of the standard enthalpies of formation obtained in this work, together with data on enthalpies of solution at infinite dilution ({delta}{sub sol}H{sup {approx}}) for crystalline dihydrate and amorphous anhydrous trehalose, allow a better insight on the thermodynamic description of the trehalose system which can provide, together with the future research on the subject, a contribution for understanding the metabolism in several organisms, as well as the phase transition between the different polymorphs.

  18. Classical Conditioning of Hippocampal Theta Patterns in the Rat.

    Science.gov (United States)

    1976-08-01

    associated with changes in performance of learned tasks , 1,4,5, 8,9 there have been very few studies of neurona l plasticity of the hippocampus It self...rapid development of a conditioned hippocampal theta response to a visual sti mulus demonstrates tha t there is considerable neurona l plasticity in the

  19. A Low energy neutrino factory for large theta(13)

    Energy Technology Data Exchange (ETDEWEB)

    Geer, Steve; Mena, Olga; /Fermilab /Rome U. /INFN, Rome; Pascoli, Silvia; /Durham U., IPPP

    2007-01-01

    If the value of {theta}{sub 13} is within the reach of the upcoming generation of long-baseline experiments, T2K and NOvA, they show that a low-energy neutrino factory, with peak energy in the few GeV range, would provide a sensitive tool to explore CP-violation and the neutrino mass hierarchy. They consider baselines with typical length 1000-1500 km. The unique performance of the low energy neutrino factory is due to the rich neutrino oscillation pattern at energies between 1 and 4 GeV at baselines {Omicron}(1000) km. They perform both a semi-analytical study of the sensitivities and a numerical analysis to explore how well this setup can measure {theta}{sub 13}, CP-violation, and determine the type of mass hierarchy and the {theta}{sub 23} quadrant. A low energy neutrino factory provides a powerful tool to resolve ambiguities and make precise parameter determinations, for both large and fairly small values of the mixing parameter {theta}{sub 13}.

  20. Midfrontal theta tracks action monitoring over multiple interactive time scales.

    Science.gov (United States)

    Cohen, Michael X

    2016-11-01

    Quickly detecting and correcting mistakes is a crucial brain function. EEG studies have identified an idiosyncratic electrophysiological signature of online error correction, termed midfrontal theta. Midfrontal theta has so far been investigated over the fast time-scale of a few hundred milliseconds. But several aspects of behavior and brain activity unfold over multiple time scales, displaying "scale-free" dynamics that have been linked to criticality and optimal flexibility when responding to changing environmental demands. Here we used a novel line-tracking task to demonstrate that midfrontal theta is a transient yet non-phase-locked response that is modulated by task performance over at least three time scales: a few hundred milliseconds at the onset of a mistake, task performance over a fixed window of the previous 5s, and scale-free-like fluctuations over many tens of seconds. These findings provide novel evidence for a role of midfrontal theta in online behavioral adaptation, and suggest new approaches for linking EEG signatures of human executive functioning to its neurobiological underpinnings.

  1. Frontal theta reflects uncertainty and unexpectedness during exploration and exploitation.

    Science.gov (United States)

    Cavanagh, James F; Figueroa, Christina M; Cohen, Michael X; Frank, Michael J

    2012-11-01

    In order to understand the exploitation/exploration trade-off in reinforcement learning, previous theoretical and empirical accounts have suggested that increased uncertainty may precede the decision to explore an alternative option. To date, the neural mechanisms that support the strategic application of uncertainty-driven exploration remain underspecified. In this study, electroencephalography (EEG) was used to assess trial-to-trial dynamics relevant to exploration and exploitation. Theta-band activities over middle and lateral frontal areas have previously been implicated in EEG studies of reinforcement learning and strategic control. It was hypothesized that these areas may interact during top-down strategic behavioral control involved in exploratory choices. Here, we used a dynamic reward-learning task and an associated mathematical model that predicted individual response times. This reinforcement-learning model generated value-based prediction errors and trial-by-trial estimates of exploration as a function of uncertainty. Mid-frontal theta power correlated with unsigned prediction error, although negative prediction errors had greater power overall. Trial-to-trial variations in response-locked frontal theta were linearly related to relative uncertainty and were larger in individuals who used uncertainty to guide exploration. This finding suggests that theta-band activities reflect prefrontal-directed strategic control during exploratory choices.

  2. On identities involving the sixth order mock theta functions

    CERN Document Server

    Lovejoy, Jeremy

    2009-01-01

    We present q-series proofs of four identities involving sixth order mock theta functions from Ramanujan's lost notebook. We also show how Ramanujan's identities can be used to give a quick proof of four sixth order identities of Berndt and Chan.

  3. Determination of {theta}{sup 12} in future experiments

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, Sandhya [INFN and SISSA, Trieste (Italy)

    2005-08-15

    We discuss the possibility of high precision measurement of solar mixing angle in future reactor and solar neutrino experiments. Reactor experiments tuned to Survival Probability MINima (SPMIN) can measure sin{sup 2}{theta}{sub 12} to within 2%(6%) at l{sigma}(3{sigma})

  4. Athletes in a Slump: Neurophysiological Evidence from Frontal Theta Activity

    Directory of Open Access Journals (Sweden)

    Jingu Kim

    2014-01-01

    Full Text Available The purpose of this study is to investigate the neurophysiological differences in athletes who suffer from a slump and other athletes who do not. Eighteen high school student athletes participated in this experiment. A subjective questionnaire was conducted to identify athletes in a slump (i.e., the slump group and not in a slump (i.e., the no-slump group. EEG data was recorded at 4 regions (left prefrontal, right prefrontal, left frontal, and right frontal. A two-way (2 groups x 4 regions ANOVA was performed on the dependent variable (i.e., frontal theta power. The findings of this study demonstrated that participants in the no-slump group showed higher frontal theta activity than their counterparts in the slump group. From the findings of this study, it is suggested that mental fatigue may cause low frontal theta activity in athletes who experience a slump. The present study makes an important contribution to the current literature by being the first to report that EEG theta power over frontal regions can be used as a marker of athletes suffering from a slump.

  5. X-alpha calculation of transition energies in multiply ionized atoms

    Science.gov (United States)

    Ringers, D. A.; Chen, M. H.

    1974-01-01

    It is shown that the accuracy of calculations can be improved if appropriate (different) values of alpha are used for each configuration. Alternatively, the Slater Transition state can be used, wherein a total energy difference is related to a difference in single electron eigenvalues. By a series expansion, the value of alpha for an excited configuration can be related to its value for the ground state configuration. The terms Delta alpha (delta Epsilon/delta alpha) exhibit a similar dependence on atomic number as the ground state values of alpha. Results of sample calculations are reported and compared with experiment.

  6. A Search for the Theta^*++ Pentaquark in B+ -> p pbar K+

    CERN Document Server

    Aubert, B; Abrams, G S; Adye, T; Ahmed, S; Alam, M S; Albert, J; Aleksan, Roy; Allison, J; Allmendinger, T; Altenburg, D; Andreotti, M; Angelini, C; Anulli, F; Aston, D; Azzolini, V; Baak, M; Back, J J; Bailey, S; Baldini-Ferroli, R; Band, H R; Banerjee, Sw; Barate, R; Bard, D J; Barlow, N R; Barlow, R J; Barrett, M; Bartoldus, R; Batignani, G; Bauer, J M; Beck, T W; Bellini, F; Benayoun, M; Berger, N; Bernard, D; Berryhill, J W; Best, D; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bianchi, F; Biasini, M; Blanc, F; Blaylock, G; Blinov, A E; Blinov, V E; Bloom, P; Bóna, M; Bondioli, M; Bonneaud, G R; Borgland, A W; Bosisio, L; Boutigny, D; Bowerman, D A; Boyarski, A M; Boyd, J T; Bozzi, C; Brandenburg, G; Brandt, T; Brau, J E; Breon, A B; Briand, H; Brochard, F; Brose, J; Brown, C L; Brown, C M; Brown, D; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Buchmüller, O L; Bulten, H; Burchat, Patricia R; Button-Shafer, J; Buzzo, A; Côté, D; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Capra, R; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Chaisanguanthum, K S; Chao, M; Charles, E; Charles, M J; Chauveau, J; Chavez, C A; Chen, A; Chen, E; Chen, J C; Chen, S; Cheng, B; Cheng, C H; Chevalier, N; Christ, S; Cibinetto, G; Clark, P J; Claus, R; Cochran, J; Colecchia, F; Coleman, J P; Contri, R; Convery, M R; Cormack, C M; Cossutti, F; Cottingham, W N; Couderc, F; Covarelli, R; Cowan, G; Crawley, H B; Cremaldi, L M; Cristinziani, M; Crosetti, G; Çuhadar-Dönszelmann, T; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; Day, C T; De Groot, N; De Nardo, Gallieno; Del Buono, L; Della Ricca, G; Di Lodovico, F; Dickopp, M; Dittongo, S; Dong, D; Dorfan, J; Dorigo, A; Druzhinin, V P; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Eckmann, R; Edwards, A J; Egede, U; Eichenbaum, A M; Eigen, G; Eisner, A M; Elmer, P; Elsen, E E; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Fabozzi, F; Faccini, R; Fan, S; Farbin, A; Feltresi, E; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Flack, R L; Flächer, H U; Flood, K T; Ford, K E; Ford, W T; Forster, I J; Forti, F; Fortin, D; Foulkes, S D; Franek, B J; Frey, R; Fritsch, M; Fry, J R; Gabathuler, Erwin; Gaidot, A; Gaillard, J M; Gaillard, J R; Galeazzi, F; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gary, J W; Gaspero, M; Gatto, C; Geddes, N I; Gill, M S; Giorgi, M A; Giraud, P F; Giroux, X; Gladney, L; Glanzman, T; Godang, R; Goetzen, K; Golubev, V B; Gopal, G P; Gowdy, S J; Graham, M; Grancagnolo, S; Green, M G; Greene, M G; Grenier, G J; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Q H; Hadavand, H K; Hadig, T; Haire, M; Halyo, V; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, A J; Hart, P A; Hartfiel, B L; Harton, J L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hicheur, A; Hill, E J; Hitlin, D G; Höcker, A; Hodgkinson, M C; Hollar, J J; Honscheid, K; Hrynóva, T; Hufnagel, D; Hulsbergen, W D; Hutchcroft, D E; Igonkina, O; Innes, W R; Ivanchenko, V N; Izen, J M; Jackson, P D; Jackson, P S; Jacobsen, R G; Jawahery, A; Jayatilleke, S M; Jessop, C P; John, M J J; Johnson, J R; Judd, D; Kadel, R W; Kadyk, J; Kagan, H; Karyotakis, Yu; Kass, R; Kelly, M P; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Kitayama, I; Knecht, N S; Koch, H; Kocian, M L; Kofler, R; Kolomensky, Yu G; Koptchev, V B; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kravchenko, E A; Krishnamurthy, M; Kroeger, R; Kroseberg, J; Kukartsev, G; Kutter, P E; Kyberd, P; Lacker, H M; Lae, C K; Lafferty, G D; Lamsa, J; Lanceri, L; Lange, D J; Langenegger, U; Lankford, A J; Laplace, S; Latham, T E; Lau, Y P; Lavin, D; Lazzaro, A; Le Diberder, F R; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Lewandowski, B; Li Gioi, L; Li, H; Libby, J; Lillard, V; Lista, L; Liu, R; LoSecco, J M; Lo Vetere, M; Lockman, W S; Lombardo, V; London, G W; Long, O; Lou, X C; Lu, A; Lü, C; Luitz, S; Luppi, E; Lusiani, A; Lüth, V; Lutz, A M; Lynch, G; Lynch, H L; Lyon, A J; MacFarlane, D B; Macri, M; Malcles, J; Mallik, U; Mancinelli, G; Mandelkern, M A; Manfredi, P F; Mangeol, D J J; Marchiori, G; Margoni, M; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mayer, B; Mazur, M A; Mazzoni, M A; McKenna, J A; McMahon, T R; Meadows, B T; Messner, R; Meyer, T I; Meyer, W T; Miftakov, V; Mihályi, A; Mir, L M; Mohanty, G B; Mohapatra, A K; Mommsen, R K; Monge, M R; Monorchio, D; Moore, T B; Morandin, M; Morgan, S E; Morganti, M; Morganti, S; Morii, M; Morton, G W; Muheim, F; Müller, D R; Müller-Pfefferkorn, R; Narsky, I; Nash, J A; Nauenberg, U; Neal, H; Negrini, M; Neri, N; Nesom, G; Nicholson, H; Nikolich, M B; Nogowski, R; O'Grady, C P; Ocariz, J; Oddone, P J; Ofte, I; Olaiya, E O; Olivas, A; Olsen, J; Onuchin, A P; Orimoto, T J; Otto, S; Ozcan, V E; Paar, H P; Paick, K; Palano, A; Palombo, F; Pan, Y; Panetta, J; Panvini, R S; Paoloni, E; Paolucci, P; Parry, R J; Passaggio, S; Patel, P M; Patrignani, C; Patteri, P; Payne, D J; Pelizaeus, M; Perazzo, A; Perl, M; Peruzzi, I M; Petersen, B A; Petersen, T C; Petrak, S; Petzold, A; Piatenko, T; Piccolo, D; Piccolo, M; Piemontese, L; Pierini, M; Pioppi, M; Piredda, G; Pivk, M; Plaszczynski, S; Playfer, S; Pompili, A; Poropat, P; Porter, F C; Posocco, M; Potter, C T; Prell, S; Prepost, R; Pripstein, M; Pulliam, T; Purohit, M V; Qi, N D; Rahatlou, S; Rahimi, A M; Rama, M; Rankin, P; Ratcliff, B N; Raven, G; Re, V; Reidy, J; Ricciardi, S; Richman, J D; Ritchie, J L; Rizzo, G; Roat, C; Roberts, D A; Robertson, S H; Robutti, E; Roe, N A; Röthel, W; Ronan, Michael T; Roney, J M; Rong, G; Roodman, A; Roos, L; Rosenberg, E I; Rotondo, M; Rubin, A E; Ryd, A; Saeed, M A; Safai-Tehrani, F; Saleem, M; Salnikov, A A; Salvatore, F; Samuel, A; Sanders, D A; Sandrelli, F; Santroni, A; Saremi, S; Sarti, A; Satpathy, A; Schalk, T; Schindler, R H; Schott, G; Schrenk, S; Schubert, J; Schubert, Klaus R; Schumm, B A; Schune, M H; Schwiening, J; Schwierz, R; Schwitters, R F; Sciacca, C; Sciolla, G; Seiden, A; Sekula, S J; Serednyakov, S I; Sharma, V; Shelkov, V G; Shen, B C; Simani, M C; Simi, G; Simonetto, F; Sinev, N B; Skovpen, Yu I; Sloane, R J; Smith, A J S; Smith, J G; Snoek, H L; Snyder, A; Sobie, R J; Soffer, A; Soha, A; Sokoloff, M D; Solodov, E P; Spaan, B; Spanier, S M; Spradlin, P; Stängle, H; Steinke, M; Stelzer, J; Stoker, D P; Stroili, R; Strom, D; Stugu, B; Su, D; Sullivan, M K; Summers, D J; Sundermann, J E; T'Jampens, S; Tan, P; Tantot, L; Taras, P; Taylor, F; Taylor, G P; Telnov, A V; Teodorescu, L; Ter-Antonian, R; Therin, G; Thiebaux, C; Thiessen, D; Tiozzo, G; Tisserand, V; Toki, W H; Torrence, E; Tosi, S; Touramanis, C; Treadwell, E; Vasileiadis, G; Vasseur, G; Vavra, J; Verderi, M; Verkerke, W; Vitale, L; Voci, C; Voena, C; Vuagnin, G; Wagner, G; Wagner, S R; Wagoner, D E; Waldi, R; Walsh, J; Wang, K; Wang, P; Wappler, F R; Watson, A T; Weaver, M; Weidemann, A W; Weinstein, A J R; Wenzel, W A; Wilden, L; Williams, D C; Williams, J C; Willocq, S; Wilson, F F; Wilson, J R; Wilson, M G; Wilson, R J; Winter, M A; Wisniewski, W J; Wittgen, M; Won, E; Wong, Q K; Wormser, G; Wright, D H; Wright, D M; Wu, J; Wu, S L; Xie, Y; Yamamoto, R K; Yang, S; Yarritu, A K; Ye, S; Yéche, C; Yi, J; Young, C C; Yu, Z; Yumiceva, F X; Yushkov, A N; Zallo, A; Zeng, Q; Zghiche, A; Zhang, J; Zhang, L; Zhao, H W; Zhu, Y S; Zito, M; De Sangro, R; La Vaissière, C de

    2004-01-01

    We report the results of a search for the Theta*++ pentaquark in the decay B+ -> Theta*++ pbar where Theta*++ -> pK+ using 81fb^-1 of data collected on the Upsilon(4S) resonance with the BaBar detector at PEP-II. We find an upper limit on the branching fraction of B+ -> Theta*++ pbar where Theta*++ -> pK+ to be 1.5x10^-7 for 1.43Theta*++)<1.85GeV/c^2, 2.4x10^-7 for 1.85Theta*++)<2.00GeV/c^2 and 3.3x10^-7 for 2.00Theta*++)<2.36GeV/c^2, at 90% confidence level. All results are preliminary.

  7. Probes for narcotic receptor mediated phenomena 22. Pt.1: Synthesis and characterization of optically pure [{sup 3}H](+)-4-[({alpha}R)-{alpha}-((2S,5R)-4-propyl-2,5-dimethyl-1-pi perazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide, [{sup 3}H]SNC 121, a novel high affinity and selective ligand for delta opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, S.N.; Bertha, C.M.; Rice, K.C. [National Inst. of Diabetes and Digestive and Kidney Diseases, Medicinal Chemistry Lab., Bethesda, MD (United States); Gutkind, J.S. [National Inst. of Dental Research, Bethesda, MD (United States); Heng Xu; Partilla, J.S.; Rothman, R.B. [National Inst. on Drug Abuse, Clinical Psychopharmacology Section, Baltimore, MD (United States)

    1996-09-01

    The synthesis of unlabelled and labelled SNC 121, a selective nonpeptide ligand for the delta opioid receptor is reported. [{sup 3}H]SNC 121 of specific activity of 26.8 Ci/mmol, was synthesized by catalytic tritiation of the optically pure precursor SNC 80. (author).

  8. Evidence that Clostridium perfringens theta-toxin induces colloid-osmotic lysis of erythrocytes.

    OpenAIRE

    Harris, R W; Sims, P J; Tweten, R K

    1991-01-01

    Clostridium perfringens theta-toxin was shown to lyse target erythrocytes by a colloid-osmotic mechanism. Analysis showed the onset of lysis of erythrocytes by theta-toxin could be temporarily stabilized with 0.3 M sucrose. Flow cytometry analysis of the size distribution of theta-toxin-treated erythrocytes showed swelling of the erythrocytes prior to lysis.

  9. Modulation of Hippocampal Theta Oscillations and Spatial Memory by Relaxin-3 Neurons of the Nucleus Incertus

    Science.gov (United States)

    Ma, Sherie; Olucha-Bordonau, Francisco E.; Hossain, M. Akhter; Lin, Feng; Kuei, Chester; Liu, Changlu; Wade, John D.; Sutton, Steven W.; Nunez, Angel; Gundlach, Andrew L.

    2009-01-01

    Hippocampal theta rhythm is thought to underlie learning and memory, and it is well established that "pacemaker" neurons in medial septum (MS) modulate theta activity. Recent studies in the rat demonstrated that brainstem-generated theta rhythm occurs through a multisynaptic pathway via the nucleus incertus (NI), which is the primary source of the…

  10. What antineutrinos can tell about octant and $\\delta_{CP}$ in DUNE?

    CERN Document Server

    Nath, Newton; Goswami, Srubabati

    2016-01-01

    We study the efficiency of DUNE, a next generation long baseline oscillation experiment to resolve two major unknowns in neutrino oscillation physics. These are, octant of $\\theta_{23}$ (i.e. if $\\theta_{23}$ is $45^\\circ$) and Dirac CP phase $\\delta_{CP}$. We mainly focus on the role of antineutrinos when they travel 1300 km baseline of DUNE. We observe that for DUNE, the antineutrino runs help to remove parameter degeneracies even in the parameter space where the antineutrino probability suffers from various degeneracies. We study these points in detail and find that, due to enhanced matter effect longer baseline experiments create an increased tension between the neutrino and the antineutrino probabilities which helps to increase total sensitivity in case of combined runs. We also find that, antineutrino run increases overall CP sensitivity due to its ability to abolish octant-$\\delta_{CP}$ degeneracy.

  11. Delta hedging strategies comparison

    DEFF Research Database (Denmark)

    De Giovanni, Domenico; Ortobelli, S.; Rachev, S.T.

    2008-01-01

    In this paper we implement dynamic delta hedging strategies based on several option pricing models. We analyze different subordinated option pricing models and we examine delta hedging costs using ex-post daily prices of S&P 500. Furthermore, we compare the performance of each subordinated model ...

  12. Horizontal Symmetries $\\Delta(150)$ and $\\Delta(600)$

    CERN Document Server

    Lam, C S

    2013-01-01

    Using group theory of mixing to examine all finite subgroups of SU(3) with an order less than 512, we found recently that only the group $\\Delta(150)$ can give rise to a correct reactor angle $\\th_{13}$ of neutrino mixing without any free parameter. It predicts $\\sin^22\\th_{13}=0.11$ and a sub-maximal atmospheric angle with $\\sin^22\\th_{23}=0.94$, in good agreement with experiment. The solar angle $\\th_{12}$, the CP phase $\\d$, and the neutrino masses $m_i$ are left as free parameters. In this article we provide more details of this case, discuss possible gain and loss by introducing right-handed symmetries, and/or valons to construct dynamical models. A simple model is discussed where the solar angle agrees with experiment, and all its mixing parameters can be obtained from the group $\\Delta(600)$ by symmetry alone. The promotion of $\\Delta(150)$ to $\\Delta(600)$ is on the one hand analogous to the promotion of $S_3$ to $S_4$ in the presence of tribimaximal mixing, and on the other hand similar to the extens...

  13. Inhibition-induced theta resonance in cortical circuits

    OpenAIRE

    Stark, Eran; Eichler, Ronny; Roux, Lisa; Fujisawa, Shigeyoshi; Rotstein, Horacio G.; Buzsáki, György

    2013-01-01

    Both circuit and single-cell properties contribute to network rhythms. In vitro, pyramidal cells exhibit theta-band membrane potential (subthreshold) resonance, but whether and how sub-threshold resonance translates into spiking resonance in behaving animals is unknown. Here, we used optogenetic activation to trigger spiking in pyramidal cells or parvalbumin immunoreactive interneurons (PV) in the hippocampus and neocortex of freely-behaving rodents. Individual directly-activated pyramidal ce...

  14. Grid cells and theta as oscillatory interference: Theory and predictions

    Science.gov (United States)

    Burgess, Neil

    2011-01-01

    The oscillatory interference model (Burgess, Barry, & O’Keefe, 2007) of grid cell firing is reviewed as an algorithmic level description of a path integration and as an implementation level description of grid cells and their inputs. New analyses concern the relationships between the variables in the model and the theta rhythm, running speed and the intrinsic firing frequencies of grid cells. New simulations concern the implementation of velocity-controlled oscillators (VCOs) with different preferred directions in different neurons. To summarize the model, the distance travelled along a specific direction is encoded by the phase of a VCO relative to a baseline frequency. Each VCO is an intrinsic membrane potential oscillation whose frequency increases from baseline as a result of depolarisation by synaptic input from speed modulated head-direction cells. Grid cell firing is driven by the VCOs whose preferred directions match the current direction of motion. VCOs are phase-reset by location-specific input from place cells to prevent accumulation of error. The baseline frequency is identified with the local average of VCO frequencies, while EEG theta frequency is identified with the global average VCO frequency and comprises two components: the frequency at zero speed, and a linear response to running speed. Quantitative predictions are given for the inter-relationships between a grid cell’s intrinsic firing frequency and grid scale, the two components of theta frequency, and the running speed of the animal. Qualitative predictions are given for the properties of the VCOs, and relationship between environmental novelty, the two components of theta, grid scale and place cell remapping. PMID:19021256

  15. The role of REM theta activity in emotional memory

    Directory of Open Access Journals (Sweden)

    Isabel Camilla Hutchison

    2015-10-01

    Full Text Available While NREM sleep has been strongly implicated in the reactivation and consolidation of memory traces, the role of REM sleep remains unclear. A growing body of research on humans and animals provide behavioral evidence for a role of REM sleep in the strengthening and modulation of emotional memories. Theta activity – which describes low frequency oscillations in the local field potential within the hippocampus, amygdala and neocortex – is a prominent feature of both wake and REM sleep in humans and rodents. Theta coherence between the hippocampus and amygdala drives large-scale PGO waves, the density of which predicts increases in plasticity-related gene expression. This could potentially facilitate the processing of emotional memory traces within the hippocampus during REM sleep. Further, the timing of hippocampal activity in relation to theta phase is vital in determining subsequent potentiation of neuronal activity. This could allow the emotionally modulated strengthening of novel and the gradual weakening of consolidated hippocampal memory traces observed in both wake and REM sleep. Hippocampal theta activity is also correlated with REM sleep acetylcholine levels – which are thought to reduce hippocampal afferent inputs in the neocortex. The additional low levels of noradrenaline during REM sleep, which facilitate recurrent activation within the neocortex, could allow the integration of novel memory traces previously consolidated during NREM sleep. We therefore propose that REM sleep mediates the prioritized processing of emotional memories within the hippocampus, the integration of previously consolidated memory traces within the neocortex, as well as the disengagement of consolidated neocortical memory traces from the hippocampus.

  16. Theta coordinated error-driven learning in the hippocampus.

    Directory of Open Access Journals (Sweden)

    Nicholas Ketz

    Full Text Available The learning mechanism in the hippocampus has almost universally been assumed to be Hebbian in nature, where individual neurons in an engram join together with synaptic weight increases to support facilitated recall of memories later. However, it is also widely known that Hebbian learning mechanisms impose significant capacity constraints, and are generally less computationally powerful than learning mechanisms that take advantage of error signals. We show that the differential phase relationships of hippocampal subfields within the overall theta rhythm enable a powerful form of error-driven learning, which results in significantly greater capacity, as shown in computer simulations. In one phase of the theta cycle, the bidirectional connectivity between CA1 and entorhinal cortex can be trained in an error-driven fashion to learn to effectively encode the cortical inputs in a compact and sparse form over CA1. In a subsequent portion of the theta cycle, the system attempts to recall an existing memory, via the pathway from entorhinal cortex to CA3 and CA1. Finally the full theta cycle completes when a strong target encoding representation of the current input is imposed onto the CA1 via direct projections from entorhinal cortex. The difference between this target encoding and the attempted recall of the same representation on CA1 constitutes an error signal that can drive the learning of CA3 to CA1 synapses. This CA3 to CA1 pathway is critical for enabling full reinstatement of recalled hippocampal memories out in cortex. Taken together, these new learning dynamics enable a much more robust, high-capacity model of hippocampal learning than was available previously under the classical Hebbian model.

  17. ON THE THETA OPERATOR FOR MODULAR FORMS MODULO PRIME POWERS

    DEFF Research Database (Denmark)

    Chen, Imin; Kiming, Ian

    2016-01-01

    We consider the classical theta operator θ on modular forms modulo pm and level N prime to p, where p is a prime greater than three. Our main result is that θ mod pm will map forms of weight k to forms of weight k+2+2pm−1(p−1) and that this weight is optimal in certain cases when m is at least two...

  18. Modular forms of orthogonal type and Jacobi theta-series

    CERN Document Server

    Clery, Fabien

    2011-01-01

    In this paper we consider Jacobi forms of half-integral index for any positive definite lattice L (classical Jacobi forms from the book of Eichler and Zagier correspond to the lattice A_1=). We give a lot of examples of Jacobi forms of singular and critical weights for root systems using Jacobi theta-series. We describe the Jacobi lifting for Jacobi forms of half-integral indices. In some case it gives additive lifting construction of new reflective modular forms.

  19. The role of REM sleep theta activity in emotional memory.

    Science.gov (United States)

    Hutchison, Isabel C; Rathore, Shailendra

    2015-01-01

    While non-REM (NREM) sleep has been strongly implicated in the reactivation and consolidation of memory traces, the role of rapid-eye movement (REM) sleep remains unclear. A growing body of research on humans and animals provide behavioral evidence for a role of REM sleep in the strengthening and modulation of emotional memories. Theta activity-which describes low frequency oscillations in the local field potential within the hippocampus, amygdala and neocortex-is a prominent feature of both wake and REM sleep in humans and rodents. Theta coherence between the hippocampus and amygdala drives large-scale pontine-geniculo-occipital (PGO) waves, the density of which predicts increases in plasticity-related gene expression. This could potentially facilitate the processing of emotional memory traces within the hippocampus during REM sleep. Further, the timing of hippocampal activity in relation to theta phase is vital in determining subsequent potentiation of neuronal activity. This could allow the emotionally modulated strengthening of novel and gradual weakening of consolidated hippocampal memory traces during REM sleep. Hippocampal theta activity is also correlated with REM sleep levels of achetylcholine - which is thought to reduce hippocampal inputs in the neocortex. The additional low levels of noradrenaline during REM sleep, which facilitate feedback within the neocortex, could allow the integration of novel memory traces previously consolidated during NREM sleep. We therefore propose that REM sleep mediates the prioritized processing of emotional memories within the hippocampus, the integration of previously consolidated memory traces within the neocortex, as well as the disengagement of consolidated neocortical memory traces from the hippocampus.

  20. Wilson Loops in 2D Noncommutative Euclidean Gauge Theory: 2. 1/\\theta Expansion

    CERN Document Server

    Ambjørn, Jan; Makeenko, Y; Ambjorn, Jan; Dubin, Andrei; Makeenko, Yuri

    2007-01-01

    We analyze the $1/\\theta$ and 1/N expansions of the Wilson loop averages $_{U_\\theta (N)}$ in the two-dimensional noncommutative $U_\\theta (N)$ gauge theory with the parameter of noncommutativity $\\theta$. For a generic rectangular contour $C$, a concise integral representation is derived (non-perturbatively both in the coupling constant $g^{2}$ and in $\\theta$) for the next-to-leading term of the $1/\\theta$ expansion. In turn, in the limit when ${\\theta}$ is much larger than the area $A(C)$ of the surface bounded by $C$, the large $\\theta$ asymptote of this representation is argued to yield the next-to-leading term of the $1/\\theta$ series. For both of the expansions, the next-to-leading contribution exhibits only a power-like decay for areas $A(C)>>\\sigma^{-1}$ (but $A(C)<<{\\theta}$) much larger than the inverse of the string tension $\\sigma$ defining the range of the exponential decay of the leading term. Consequently, for large $\\theta$, it hinders a direct stringy interpretation of the subleading t...

  1. $\\theta$ dependence of 4D $SU(N)$ gauge theories in the large-$N$ limit

    CERN Document Server

    Bonati, Claudio; Rossi, Paolo; Vicari, Ettore

    2016-01-01

    We study the large-$N$ scaling behavior of the $\\theta$ dependence of the ground-state energy density $E(\\theta)$ of four-dimensional (4D) $SU(N)$ gauge theories and two-dimensional (2D) $CP^{N-1}$ models, where $\\theta$ is the parameter associated with the Lagrangian topological term. We consider its $\\theta$ expansion around $\\theta=0$, $E(\\theta)-E(0) = {1\\over 2}\\chi \\,\\theta^2 ( 1 + b_2 \\theta^2 + b_4\\theta^4 +\\cdots)$ where $\\chi$ is the topological susceptibility and $b_{2n}$ are dimensionless coefficients. We focus on the first few coefficients $b_{2n}$, which parametrize the deviation from a simple Gaussian distribution of the topological charge at $\\theta=0$. We present a numerical analysis of Monte Carlo simulations of 4D $SU(N)$ lattice gauge theories for $N=3,\\,4,\\,6$ in the presence of an imaginary $\\theta$ term. The results provide a robust evidence of the large-$N$ behavior predicted by standard large-$N$ scaling arguments, i.e. $b_{2n}= O(N^{-2n})$. In particular, we obtain $b_2=\\bar{b}_2/N^2...

  2. A Modified Theta Projection Model for Creep Behavior of Metals and Alloys

    Science.gov (United States)

    Kumar, Manish; Singh, I. V.; Mishra, B. K.; Ahmad, S.; Venugopal Rao, A.; Kumar, Vikas

    2016-09-01

    In this work, a modified theta projection model is proposed for the constitutive modeling of creep behavior of metals and alloys. In the conventional theta projection model, strain hardening exponent is a function of time and theta, whereas in the modified theta projection model, the exponent is taken as a function of time, theta, and applied stress. The results obtained by the modified theta projection model for Al 2124 T851 alloy at constant uniaxial tensile stress are compared with the experimental results and with the predictions of the conventional theta projection method. The creep behavior of Al 7075 T651 alloy is also predicted using modified and conventional theta projection model and compared with the available experimental data. It is observed that the modified theta projection model captures the creep behavior more accurately as compared to the conventional theta projection model. The modified theta projection model can be used to predict the creep strain of pure metals and class M alloys (similar creep behavior to pure metals) for intermediate range of stress and temperature.

  3. Recurrent RBFN-based fuzzy neural network control for X-Y-theta motion control stage using linear ultrasonic motors.

    Science.gov (United States)

    Lin, Faa-Jeng; Shieh, Po-Huang

    2006-12-01

    A recurrent radial basis function network (RBFN) based fuzzy neural network (FNN) control system is proposed to control the position of an X-Y-theta motion control stage using linear ultrasonic motors (LUSMs) to track various contours in this study. The proposed recurrent RBFN-based FNN combines the merits of self-constructing fuzzy neural network (SCFNN), recurrent neural network (RNN), and RBFN. Moreover, the structure and the parameter learning phases of the recurrent RBFN-based FNN are performed concurrently and on line. The structure learning is based on the partition of input space, and the parameter learning is based on the supervised gradient decent method using a delta adaptation law. The experimental results due to various contours show that the dynamic behaviors of the proposed recurrent RBFN-based FNN control system are robust with regard to uncertainties.

  4. Background-independent measurement of $\\theta_{13}$ in Double Chooz

    CERN Document Server

    Abe, Y; Barriere, J C; Baussan, E; Bekman, I; Bergevin, M; Bezerra, T J C; Bezrukov, L; Blucher, E; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chauveau, E; Chimenti, P; Collin, A P; Conover, E; Conrad, J M; Crespo-Anadón, J I; Crum, K; Cucoanes, A; Damon, E; Dawson, J V; Dietrich, D; Djurcic, Z; Dracos, M; Elnimr, M; Etenko, A; Fallot, M; von Feilitzsch, F; Felde, J; Fernandes, S M; Fischer, V; Franco, D; Franke, M; Furuta, H; Gil-Botella, I; Giot, L; Göger-Neff, M; Gonzalez, L F G; Goodenough, L; Goodman, M C; Grant, C; Haag, N; Hara, T; Haser, J; Hofmann, M; Horton-Smith, G A; Hourlier, A; Ishitsuka, M; Jochum, J; Jollet, C; Kaether, F; Kalousis, L N; Kamyshkov, Y; Kaplan, D M; Kawasaki, T; Kemp, E; de Kerret, H; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; López-Casta\; LoSecco, J M; Lucht, S; Maeda, J; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Miletic, T; Milincic, R; Minotti, A; Nagasaka, Y; Nakajima, K; Nikitenko, Y; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Palomares, C; Pepe, I M; Perasso, S; Pfahler, P; Porta, A; Pronost, G; Reichenbacher, J; Reinhold, B; Röhling, M; Roncin, R; Roth, S; Rybolt, B; Sakamoto, Y; Santorelli, R; Sato, F; Schilithz, A C; Schönert, S; Schoppmann, S; Shaevitz, M H; Sharankova, R; Shimojima, S; Sibille, V; Sinev, V; Skorokhvatov, M; Smith, E; Spitz, J; Stahl, A; Stancu, I; Stokes, L F F; Strait, M; Stüken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Svoboda, R; Terao, K; Tonazzo, A; Thi, H H Trinh; Valdiviesso, G; Vassilopoulos, N; Veyssiere, C; Vivier, M; Wagner, S; Watanabe, H; Wiebusch, C; Winslow, L; Wurm, M; Yang, G; Yermia, F; Zimmer, V

    2014-01-01

    The oscillation results published by the Double Chooz collaboration in 2011 and 2012 rely on background models substantiated by reactor-on data. In this analysis, we present a background-model-independent measurement of the mixing angle $\\theta_{13}$ by including 7.53 days of reactor-off data. A global fit of the observed neutrino rates for different reactor power conditions is performed, yielding a measurement of both $\\theta_{13}$ and the total background rate. The results on the mixing angle are improved significantly by including the reactor-off data in the fit, as it provides a direct measurement of the total background rate. This reactor rate modulation analysis considers antineutrino candidates with neutron captures on both Gd and H, whose combination yields $\\sin^2(2\\theta_{13})=$ 0.102 $\\pm$ 0.028(stat.) $\\pm$ 0.033(syst.). The results presented in this study are fully consistent with the ones already published by Double Chooz, achieving a competitive precision. They provide, for the first time, a de...

  5. Cosmological lepton asymmetry with a nonzero mixing angle $\\theta_{13}$

    CERN Document Server

    Castorina, Emanuele; Lattanzi, Massimiliano; Lesgourgues, Julien; Mangano, Gianpiero; Melchiorri, Alessandro; Pastor, Sergio

    2012-01-01

    While the baryon asymmetry of the Universe is nowadays well measured by cosmological observations, the bounds on the lepton asymmetry in the form of neutrinos are still significantly weaker. We place limits on the relic neutrino asymmetries using some of the latest cosmological data, taking into account the effect of flavor oscillations. We present our results for two different values of the neutrino mixing angle \\theta_{13}, and show that for large \\theta_{13} the limits on the total neutrino asymmetry become more stringent, diluting even large initial flavor asymmetries. In particular, we find that the present bounds are still dominated by the limits coming from Big Bang Nucleosynthesis, while the limits on the total neutrino mass from cosmological data are essentially independent of \\theta_{13}. Finally, we perform a forecast for COrE, taken as an example of a future CMB experiment, and find that it could improve the limits on the total lepton asymmetry approximately by up to a factor 5.

  6. Theta signal as the neural signature of social exclusion.

    Science.gov (United States)

    Cristofori, Irene; Moretti, Laura; Harquel, Sylvain; Posada, Andres; Deiana, Gianluca; Isnard, Jean; Mauguière, François; Sirigu, Angela

    2013-10-01

    The feeling of being excluded from a social interaction triggers social pain, a sensation as intense as actual physical pain. Little is known about the neurophysiological underpinnings of social pain. We addressed this issue using intracranial electroencephalography in 15 patients performing a ball game where inclusion and exclusion blocks were alternated. Time-frequency analyses showed an increase in power of theta-band oscillations during exclusion in the anterior insula (AI) and posterior insula, the subgenual anterior cingulate cortex (sACC), and the fusiform "face area" (FFA). Interestingly, the AI showed an initial fast response to exclusion but the signal rapidly faded out. Activity in the sACC gradually increased and remained significant thereafter. This suggests that the AI may signal social pain by detecting emotional distress caused by the exclusion, whereas the sACC may be linked to the learning aspects of social pain. Theta activity in the FFA was time-locked to the observation of a player poised to exclude the participant, suggesting that the FFA encodes the social value of faces. Taken together, our findings suggest that theta activity represents the neural signature of social pain. The time course of this signal varies across regions important for processing emotional features linked to social information.

  7. Neutrino Mixing from $\\Delta(6n^2)$ Groups

    CERN Document Server

    Neder, Thomas

    2014-01-01

    Experimentally viable lepton mixing parameters can be predicted in so-called direct flavour models with Majorana neutrinos using $\\Delta(6n^2)$ groups as a flavour group. In direct models, in which the flavour group is broken to a $Z_2\\times Z_2$ subgroup in the neutrino sector, mixing angles and Dirac CP phase are purely predicted from symmetry. General predictions of direct models with $\\Delta(6n^2)$ flavour groups are that all mixing angles are fixed up to a discrete choice and that the Dirac CP phase is $0$ or $\\pi$; Furthermore, the middle column of the mixing matrix is trimaximal which yields the sum rule $\\theta_{23}=45^\\circ \\mp \\theta_{13}/\\sqrt{2}$ depending on the Dirac phase. These predictions of lepton mixing parameters are compatible with recent global fit results or will be tested experimentally in the near future. It is the first time that such predictions have been obtained model-independently for an infinite series of groups.

  8. Prospects of probing $\\theta_{13}$ and neutrino mass hierarchy by Supernova Neutrinos in KamLAND

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Kar, K; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati; Kar, Kamales

    2003-01-01

    In this paper we study the physics potential of the KamLAND detector in probing neutrino oscillation parameters through observation of supernova neutrinos. In particular, we discuss the possibilities of probing the mixing angle $\\theta_{13}$ and determining the sign of $\\Delta m^2_{32}$ from the total charged current(CC) event rates on the proton and $^{12}{C}$ target, as well as from the CC spectra. We discuss the chances of probing the earth matter effect induced modulations from the observation of CC spectra in the different CC reactions in KamLAND and find the volume required to get a statistically significant signature of the earth matter effect in different energy bins. We also calculate the event rates expected in the neutral current (NC) reactions on Carbon and free proton and investigate if the charged current to neutral current ratios, which are free of the absolute luminosity uncertainty in the supernova neutrino fluxes, can be useful in probing the oscillation parameters.

  9. On the width of N-Delta and Delta-Delta states

    CERN Document Server

    Niskanen, J A

    2016-01-01

    It is seen by a coupled-channel calculation that in the two-baryon N-Delta or Delta-Delta system the width of the state is greatly diminished due to the relative kinetic energy of the two baryons, since the internal energy of the particles, available for pionic decay, is smaller. A similar state dependent effect arises from the centrifugal barrier in N-Delta or Delta-Delta systems with non-zero orbital angular momentum. The double-Delta width can become even smaller than the free width of a single Delta. This has some bearing to the interpretation of the d'(2380) resonance recently discovered at COSY.

  10. Toward using alpha and theta brain waves to quantify programmer expertise.

    Science.gov (United States)

    Crk, Igor; Kluthe, Timothy

    2014-01-01

    Empirical studies of programming language learnability and usability have thus far depended on indirect measures of human cognitive performance, attempting to capture what is at its essence a purely cognitive exercise through various indicators of comprehension, such as the correctness of coding tasks or the time spent working out the meaning of code and producing acceptable solutions. Understanding program comprehension is essential to understanding the inherent complexity of programming languages, and ultimately, having a measure of mental effort based on direct observation of the brain at work will illuminate the nature of the work of programming. We provide evidence of direct observation of the cognitive effort associated with programming tasks, through a carefully constructed empirical study using a cross-section of undergraduate computer science students and an inexpensive, off-the-shelf brain-computer interface device. This study presents a link between expertise and programming language comprehension, draws conclusions about the observed indicators of cognitive effort using recent cognitive theories, and proposes directions for future work that is now possible.

  11. EEG Theta and Alpha Responses Reveal Qualitative Differences in Processing Taxonomic versus Thematic Semantic Relationships

    Science.gov (United States)

    Maguire, Mandy J.; Brier, Matthew R.; Ferree, Thomas C.

    2010-01-01

    Despite the importance of semantic relationships to our understanding of semantic knowledge, the nature of the neural processes underlying these abilities are not well understood. In order to investigate these processes, 20 healthy adults listened to thematically related (e.g., leash-dog), taxonomically related (e.g., horse-dog), or unrelated…

  12. Brain Responses to a 6-Hz Binaural Beat: Effects on General Theta Rhythm and Frontal Midline Theta Activity

    Directory of Open Access Journals (Sweden)

    Nantawachara Jirakittayakorn

    2017-06-01

    Full Text Available A binaural beat is a beat phenomenon that is generated by the dichotic presentation of two almost equivalent pure tones but with slightly different frequencies. The brain responses to binaural beats remain controversial; therefore, the aim of this study was to investigate theta activity responses to a binaural beat by controlling factors affecting localization, including beat frequency, carrier tone frequency, exposure duration, and recording procedure. Exposure to a 6-Hz binaural beat on a 250 Hz carrier tone for 30 min was utilized in this study. Quantitative electroencephalography (QEEG was utilized as the recording modality. Twenty-eight participants were divided into experimental and control groups. Emotional states were evaluated by Brunel Mood Scale (BRMUS before and after exposing to the stimulus. The results showed that theta activity was induced in the entire cortex within 10 min of exposure to the stimulus in the experimental group. Compared to the control group, theta activity was also induced at the frontal and parietal-central regions, which included the Fz position, and left hemisphere dominance was presented for other exposure durations. The pattern recorded for 10 min of exposure appeared to be brain functions of a meditative state. Moreover, tension factor of BRUMS was decreased in experimental group compared to control group which resembled the meditation effect. Thus, a 6-Hz binaural beat on a 250 Hz carrier tone was suggested as a stimulus for inducing a meditative state.

  13. Brain Responses to a 6-Hz Binaural Beat: Effects on General Theta Rhythm and Frontal Midline Theta Activity.

    Science.gov (United States)

    Jirakittayakorn, Nantawachara; Wongsawat, Yodchanan

    2017-01-01

    A binaural beat is a beat phenomenon that is generated by the dichotic presentation of two almost equivalent pure tones but with slightly different frequencies. The brain responses to binaural beats remain controversial; therefore, the aim of this study was to investigate theta activity responses to a binaural beat by controlling factors affecting localization, including beat frequency, carrier tone frequency, exposure duration, and recording procedure. Exposure to a 6-Hz binaural beat on a 250 Hz carrier tone for 30 min was utilized in this study. Quantitative electroencephalography (QEEG) was utilized as the recording modality. Twenty-eight participants were divided into experimental and control groups. Emotional states were evaluated by Brunel Mood Scale (BRMUS) before and after exposing to the stimulus. The results showed that theta activity was induced in the entire cortex within 10 min of exposure to the stimulus in the experimental group. Compared to the control group, theta activity was also induced at the frontal and parietal-central regions, which included the Fz position, and left hemisphere dominance was presented for other exposure durations. The pattern recorded for 10 min of exposure appeared to be brain functions of a meditative state. Moreover, tension factor of BRUMS was decreased in experimental group compared to control group which resembled the meditation effect. Thus, a 6-Hz binaural beat on a 250 Hz carrier tone was suggested as a stimulus for inducing a meditative state.

  14. Purplebook Delta: For Improving Performance in an Established Position in Higher Education.

    Science.gov (United States)

    Coole, Walter A.

    The "Purplebook" is an essential part of the "Greenbook System", which is an integrated sequence of five individualized programs (Alpha, Beta, Gamma, Delta, Epsilon) designed for the professional development of college educators. The Delta program is aimed at professional staff in higher education who are just completing…

  15. Modulation of induced frontocentral theta (Fm-theta) event-related (de-)synchronisation dynamics following mindfulness-based cognitive therapy in Major Depressive Disorder

    NARCIS (Netherlands)

    Schoenberg, P.L.; Speckens, A.E.M.

    2014-01-01

    Depressive severity has been associated with attenuated neocortical frontal midline theta (Fm-theta) power/evoked activity. Mindfulness-Based Cognitive Therapy (MBCT) has shown to be a successful novel intervention for Major Depressive Disorder (MDD), albeit precise working mechanisms remain elusive

  16. Alpha Blockers

    Science.gov (United States)

    ... positive side, alpha blockers might decrease low-density lipoprotein (LDL) cholesterol (the "bad" cholesterol). Alpha blockers can ... PreventionTreatmentofHighBloodPressure/Types-of-Blood-Pressure-Medications_UCM_303247_Article.jsp. Accessed June 4, 2016. Kaplan NM, et ...

  17. geomorphology_delta

    Data.gov (United States)

    California Department of Resources — Surficial geology of the Delta area of California by Brian Atwater of the U.S. Geological Survey. Source maps are from the USGS publication MF-1401. This digital...

  18. Delta-Reliability

    OpenAIRE

    Eugster, P.; Guerraoui, R.; Kouznetsov, P.

    2001-01-01

    This paper presents a new, non-binary measure of the reliability of broadcast algorithms, called Delta-Reliability. This measure quantifies the reliability of practical broadcast algorithms that, on the one hand, were devised with some form of reliability in mind, but, on the other hand, are not considered reliable according to the ``traditional'' notion of broadcast reliability [HT94]. Our specification of Delta-Reliability suggests a further step towards bridging the gap between theory and...

  19. Examination of the role of the $^{14}$O($\\alpha$,$p$)$^{17}$F reaction rate in type I x-ray bursts

    CERN Document Server

    Hu, J; Parikh, A; Xu, S W; Yamaguchi, H; Kahl, D; Ma, P; Su, J; Wang, H W; Nakao, T; Wakabayashi, Y; Teranishi, T; Hahn, K I; Moon, J Y; Jung, H S; Hashimoto, T; Chen, A A; Irvine, D; Lee, C S; Kubono, S

    2014-01-01

    The $^{14}$O($\\alpha$,$p$)$^{17}$F reaction is one of the key reactions involved in the breakout from the hot-CNO cycle to the rp-process in type I x-ray bursts (XRBs). The resonant properties in the compound nucleus $^{18}$Ne have been investigated through resonant elastic scattering of $^{17}$F+$p$. The radioactive $^{17}$F beam was separated by the CNS Radioactive Ion Beam separator (CRIB) and bombarded a thick H$_2$ gas target at 3.6 MeV/nucleon. The recoiling light particles were measured by three ${\\Delta}$E-E silicon telescopes at laboratory angles of $\\theta$$_{lab}$$\\approx$3$^\\circ$, 10$^\\circ$ and 18$^\\circ$, respectively. Five resonances at $E_{x}$=6.15, 6.28, 6.35, 6.85, and 7.05 MeV were observed in the excitation functions, and their spin-parities have been determined based on an $R$-matrix analysis. In particular, $J^{\\pi}$=1$^-$ was firmly assigned to the 6.15-MeV state which dominates the thermonuclear $^{14}$O($\\alpha$,$p$)$^{17}$F rate below 2 GK. As well, a possible new excited state in $...

  20. Properties of resonant states in 18Ne relevant to key 14O(alpha,p)17F breakout reaction in type I x-ray bursts

    CERN Document Server

    Hu, J; Parikh, A; Xu, S W; Yamaguchi, H; Kahl, D; Ma, P; Su, J; Wang, H W; Nakao, T; Wakabayashi, Y; Teranishi, T; Hahn, K I; Moon, J Y; Sung, H S; Hashimoto, T; Chen, A A; Irvine, D; Lee, C S; Kubono, S

    2014-01-01

    The $^{14}$O($\\alpha$,$p$)$^{17}$F reaction is one of the key reactions involved in the breakout from the hot-CNO cycle to the rp-process in type I x-ray bursts. The resonant properties in the compound nucleus $^{18}$Ne have been investigated through resonant elastic scattering of $^{17}$F+$p$. The radioactive $^{17}$F beam was separated by the CNS Radioactive Ion Beam separator (CRIB) and bombarded a thick H$_2$ gas target at 3.6 MeV/nucleon. The recoiling light particles were measured by using three ${\\Delta}$E-E silicon telescopes at laboratory angles of $\\theta$$_{lab}$$\\approx$3$^\\circ$, 10$^\\circ$ and 18$^\\circ$, respectively. Five resonances at $E_{x}$=6.15, 6.28, 6.35, 6.85, and 7.05 MeV were observed in the excitation functions. Based on an $R$-matrix analysis, $J^{\\pi}$=1$^-$ was firmly assigned to the 6.15-MeV state. This state dominates the thermonuclear $^{14}$O($\\alpha$,$p$)$^{17}$F rate below 1 GK. We have also confirmed the existence and spin-parities of three states between 6.1 and 6.4 MeV. A...

  1. Theta Brain Rhythms Index Perceptual Narrowing in Infant Speech Perception

    Directory of Open Access Journals (Sweden)

    Alexis eBosseler

    2013-10-01

    Full Text Available The development of speech perception shows a dramatic transition between infancy and adulthood. Between 6 and 12 months, infants’ initial ability to discriminate all phonetic units across the worlds’ languages narrows—native discrimination increases while nonnative discrimination shows a steep decline. We used magnetoencephalography (MEG to examine whether brain oscillations in the theta band (4-8Hz, reflecting increases in attention and cognitive effort, would provide a neural measure of the perceptual narrowing phenomenon in speech. Using an oddball paradigm, we varied speech stimuli in two dimensions, stimulus frequency (frequent vs. infrequent and language (native vs. nonnative speech syllables and tested 6-month-old infants, 12-month-old infants, and adults. We hypothesized that 6-month-old infants would show increased relative theta power (RTP for frequent syllables, regardless of their status as native or nonnative syllables, reflecting young infants’ attention and cognitive effort in response to highly frequent stimuli (statistical learning. In adults, we hypothesized increased RTP for nonnative stimuli, regardless of their presentation frequency, reflecting increased cognitive effort for nonnative phonetic categories. The 12-month-old infants were expected to show a pattern in transition, but one more similar to adults than to 6-month-old infants. The MEG brain rhythm results supported these hypotheses. We suggest that perceptual narrowing in speech perception is governed by an implicit learning process. This learning process involves an implicit shift in attention from frequent events (infants to learned categories (adults. Theta brain oscillatory activity may provide an index of perceptual narrowing beyond speech, and would offer a test of whether the early speech learning process is governed by domain-general or domain-specific processes.

  2. Purplebook Alpha: For Pre-Professional Trainees in Higher Education.

    Science.gov (United States)

    Reitan, Henry M.; Coole, Walter A.

    The "Purplebook" is an essential part of the "Greenbook System"--an integrated sequence of five programs (Alpha, Beta, Gamma, Delta, and Epsilon) for professional development of college educators. The Alpha program is designed for college seniors or graduate students preparing for careers in higher education. Purplebook Alpha…

  3. Inhibition of alpha oscillations through serotonin-2A receptor activation underlies the visual effects of ayahuasca in humans.

    Science.gov (United States)

    Valle, Marta; Maqueda, Ana Elda; Rabella, Mireia; Rodríguez-Pujadas, Aina; Antonijoan, Rosa Maria; Romero, Sergio; Alonso, Joan Francesc; Mañanas, Miquel Àngel; Barker, Steven; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-07-01

    Ayahuasca is an Amazonian psychotropic plant tea typically obtained from two plants, Banisteriopsis caapi and Psychotria viridis. It contains the psychedelic 5-HT2A and sigma-1 agonist N,N-dimethyltryptamine (DMT) plus β-carboline alkaloids with monoamine-oxidase (MAO)-inhibiting properties. Although the psychoactive effects of ayahuasca have commonly been attributed solely to agonism at the 5-HT2A receptor, the molecular target of classical psychedelics, this has not been tested experimentally. Here we wished to study the contribution of the 5-HT2A receptor to the neurophysiological and psychological effects of ayahuasca in humans. We measured drug-induced changes in spontaneous brain oscillations and subjective effects in a double-blind randomized placebo-controlled study involving the oral administration of ayahuasca (0.75mg DMT/kg body weight) and the 5-HT2A antagonist ketanserin (40mg). Twelve healthy, experienced psychedelic users (5 females) participated in four experimental sessions in which they received the following drug combinations: placebo+placebo, placebo+ayahuasca, ketanserin+placebo and ketanserin+ayahuasca. Ayahuasca induced EEG power decreases in the delta, theta and alpha frequency bands. Current density in alpha-band oscillations in parietal and occipital cortex was inversely correlated with the intensity of visual imagery induced by ayahuasca. Pretreatment with ketanserin inhibited neurophysiological modifications, reduced the correlation between alpha and visual effects, and attenuated the intensity of the subjective experience. These findings suggest that despite the chemical complexity of ayahuasca, 5-HT2A activation plays a key role in the neurophysiological and visual effects of ayahuasca in humans.

  4. Is $n\\sin\\theta$ conserved along light path?

    CERN Document Server

    Noorbala, Mahdiyar

    2016-01-01

    Snell's law states that the quantity $n\\sin\\theta$ is unchanged in refraction of light passing from one medium to another. We inquire whether this is true in the general case where the speed of light varies continuously within a medium. It turns out to be an instructive exercise in application of Snell's law and Fermat's principle. It also provides good pedagogical problems in calculus of variations to deal with the subtleties of a variable domain of integration and inclusion of constraints. The final result of these exercises is that, contrary to an initial expectation, the answer to the question in the title is negative.

  5. Tracking EEG changes in response to alpha and beta binaural beats.

    Science.gov (United States)

    Vernon, D; Peryer, G; Louch, J; Shaw, M

    2014-07-01

    A binaural beat can be produced by presenting two tones of a differing frequency, one to each ear. Such auditory stimulation has been suggested to influence behaviour and cognition via the process of cortical entrainment. However, research so far has only shown the frequency following responses in the traditional EEG frequency ranges of delta, theta and gamma. Hence a primary aim of this research was to ascertain whether it would be possible to produce clear changes in the EEG in either the alpha or beta frequency ranges. Such changes, if possible, would have a number of important implications as well as potential applications. A secondary goal was to track any observable changes in the EEG throughout the entrainment epoch to gain some insight into the nature of the entrainment effects on any changes in an effort to identify more effective entrainment regimes. Twenty two healthy participants were recruited and randomly allocated to one of two groups, each of which was exposed to a distinct binaural beat frequency for ten 1-minute epochs. The first group listened to an alpha binaural beat of 10 Hz and the second to a beta binaural beat of 20 Hz. EEG was recorded from the left and right temporal regions during pre-exposure baselines, stimulus exposure epochs and post-exposure baselines. Analysis of changes in broad-band and narrow-band amplitudes, and frequency showed no effect of binaural beat frequency eliciting a frequency following effect in the EEG. Possible mediating factors are discussed and a number of recommendations are made regarding future studies, exploring entrainment effects from a binaural beat presentation. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Precision measurements of {sigma}{sub hadronic} for {alpha}{sub eff}(E) at ILC energies and (g-2){sub {mu}}

    Energy Technology Data Exchange (ETDEWEB)

    Jegerlehner, F. [Humboldt-Universitaet zu Berlin, Institut fuer Physik Newtonstrasse 15, D-12489 Berlin (Germany); Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen (Germany)

    2006-12-15

    A more precise determination of the effective fine structure constant {alpha}{sub eff}(E) is mandatory for confronting data from future precision experiments with precise SM predictions. Higher precision would help a lot in monitoring new physics by increasing the significance of any deviation from theory. At a future e{sup +}e{sup -}-collider like the ILC, as at LEP before, {alpha}{sub eff}(E) plays the role the static zero momentum {alpha}={alpha}{sub eff}(0) plays in low energy physics. However, by going to the effective version of {alpha} one loses about a factor 2x10{sup 2} at E=m{sub {mu}} to 10{sup 5} at E=M{sub Z} in precision, such that for physics at the gauge boson mass scale and beyond {alpha}{sub eff}(E) is the least known basic parameter, about a factor 20 less precise than the neutral gauge boson mass M{sub Z} and by about a factor 60 less precise than the Fermi constant G{sub F}. Examples of precision limitations are {alpha}{sub eff}(m{sub {mu}}) which limits the theoretical precision of the muon anomalous magnetic moment a{sub {mu}} and {alpha}{sub eff}(M{sub Z}) which limits the accuracy of the prediction of the weak mixing parameter sin{sup 2}{theta}{sub f} and indirectly the upper bound on the Higgs mass m{sub H}. An optima exploitation of a future linear collider for precision physics requires an improvement of the precision of {alpha}{sub eff}(E) by something like a factor ten. We discuss a strategy which should be able to reach this goal by appropriate efforts in performing dedicated measurements of {sigma}{sub hadronic} in a wide energy range as well as efforts in theory and in particular improving the precision of the QCD parameters {alpha}{sub s}, m{sub c} and m{sub b} by lattice QCD and/or more precise determinations of them by experiments and perturbative QCD efforts. Projects at VEPP-2000 (Novosibirsk) and DANAE/KLOE-2 (Frascati) are particularly important for improving on {alpha}{sub eff}(M{sub Z}) as well as {alpha}{sub eff}(m{sub {mu

  7. Exploration of Mars using Delta Differential One-Way Ranging based on Triangle Libration Points in the Earth-Moon system

    Science.gov (United States)

    Liu, Peng; Tang, Jingshi; Hou, Xiyun; Liu, Lin

    Very Long Baseline Interferometry (VLBI) is a technique that allows determination of angular position for distant radio sources by measuring the geometric time delay between received radio signals at two geographically separated stations. An application of VLBI is spacecraft navigation in space missions where delay measurements of a spacecraft radio signal are compared against similar delay measurements of angularly nearby quasar radio signals. In the case where the spacecraft measurements are obtained from the phases of tones emitted from the spacecraft, first detected separately at each station, and then differenced, this application of VLBI is known as Delta Differential One-Way Ranging (Delta-DOR). Even though data acquisition and processing are not identical for the spacecraft and quasar, they have similar information content and similar sensitivity to sources of error. Consequently, the Delta-DOR can be used in conjunction with Doppler and ranging data to improve spacecraft navigation by more efficiently determining spacecraft angular position in the plane-of-sky. Over the decades, human exploration of Mars have never been stopped. As we know, Delta-DOR began to serve its purpose for Mars Odyssey spacecraft in 2001. In the following years, Delta-DOR was used from Mars Exploration Rover (MER) in 2003-2004 to Mars Science Laboratory (MSL) in 2011, all with excellent results. At present, human exploration of Mars using Delta-DOR technique mainly depends on the Earth-based ground stations. As we know, the differential time delay between the spacecraft and quasar is given approximately by begin{math}Deltatau=-frac{1}{c}BsinTheta_{1}(DeltaTheta_{B}) , the accuracy of the determination of angular separation begin{math}DeltaTheta_{B} improves as the measurement error in the observable begin{math}Deltatau decreases. Further, begin{math}DeltaTheta_{B} accuracy improves as the baseline length B increases. Therefore, the introduction of special libration points, i

  8. Alpha fetoprotein

    Science.gov (United States)

    Fetal alpha globulin; AFP ... Greater than normal levels of AFP may be due to: Cancer in testes , ovaries, biliary (liver secretion) tract, stomach, or pancreas Cirrhosis of the liver Liver cancer ...

  9. Immunolocalization of Delta-Giardin within the Ventral Disc in of Trophozoites and in cysts of Giardia duodenalis using the Multiplex Laser Scanning Confocal Microscopy

    Science.gov (United States)

    Immunolocalization of alpha2-, beta- and delta-giardin in Giardia showed that in the trophozoites and cysts delta-giardin it strictly associated with the ventral disc. Optical sectioning of the ventral discs, together with quantitative colocalization of the immunoreactivity for delta- and beta-giard...

  10. Fluctuating inhibitory inputs promote reliable spiking at theta frequencies in hippocampal interneurons

    OpenAIRE

    Duluxan eSritharan; Frances K Skinner

    2012-01-01

    Theta frequency (4-12 Hz) rhythms in the hippocampus play important roles in learning and memory. CA1 interneurons located at the stratum lacunosum-moleculare and radiatum junction (LM/RAD) are thought to contribute to hippocampal theta population activities by rhythmically pacing pyramidal cells with inhibitory postsynaptic potentials. This implies that LM/RAD cells need to fire reliably at theta frequencies in vivo. To determine whether this could occur, we use biophysically-based LM/RAD mo...

  11. Hippocampal theta phase-contingent memory retrieval in delay and trace eyeblink conditioning.

    Science.gov (United States)

    Waselius, Tomi; Pöllänen, Eveliina; Wikgren, Jan; Penttonen, Markku; Nokia, Miriam S

    2017-09-04

    Hippocampal theta oscillations (3-12Hz) play a prominent role in learning. It has been suggested that encoding and retrieval of memories are supported by different phases of the theta cycle. Our previous study on trace eyeblink conditioning in rabbits suggests that the timing of the conditioned stimulus (CS) in relation to theta phase affects encoding but not retrieval of the memory trace. Here, we directly tested the effects of hippocampal theta phase on memory retrieval in two experiments conducted on adult female New Zealand White rabbits. In Experiment 1, animals were trained in trace eyeblink conditioning followed by extinction, and memory retrieval was tested by presenting the CS at troughs and peaks of the theta cycle during different stages of learning. In Experiment 2, animals were trained in delay conditioning either contingent on a high level of theta or at a random neural state. Conditioning was then followed by extinction conducted either at a random state, contingent on theta trough or contingent on theta peak. Our current results indicate that the phase of theta at CS onset has no effect on the performance of the behavioral learned response at any stage of classical eyeblink conditioning or extinction. In addition, theta-contingent trial presentation does not improve learning during delay eyeblink conditioning. The results are consistent with our earlier findings and suggest that the theta phase alone is not sufficient to affect learning at the behavioral level. It seems that the retrieval of recently acquired memories and consequently performing a learned response is moderated by neural mechanisms other than hippocampal theta. Copyright © 2017. Published by Elsevier B.V.

  12. High Precision Measurements of $\\theta_{\\odot}$ in Solar and Reactor Neutrino Experiments

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Petcov, S T; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati

    2004-01-01

    We discuss the possibilities of high precision measurement of the solar neutrino mixing angle $\\theta_\\odot \\equiv \\theta_{12}$ in solar and reactor neutrino experiments. The improvements in the determination of $\\sin^2\\theta_{12}$, which can be achieved with the expected increase of statistics and reduction of systematic errors in the currently operating solar and KamLAND experiments, are summarised. The potential of LowNu $\

  13. An asteroseismic study of the beta Cephei star theta Ophiuchi: constraints on global stellar parameters and core overshooting

    CERN Document Server

    Briquet, M; Thoul, A; Scuflaire, R; Miglio, A; Montalban, J; Dupret, M -A; Aerts, C

    2007-01-01

    We present a seismic study of the beta Cephei star theta Ophiuchi. Our analysis is based on the observation of one radial mode, one rotationally split l = 1 triplet and three components of a rotationally split l = 2 quintuplet for which the m-values were well identified by spectroscopy. We identify the radial mode as fundamental, the triplet as p_1 and the quintuplet as g_1. Our NLTE abundance analysis results in a metallicity and CNO abundances in full agreement with the most recent updated solar values. With X \\in [0.71,0.7211] and Z \\in [0.009,0.015], and using the Asplund et al. (2005) mixture but with a Ne abundance about 0.3 dex larger (Cunha et al. 2006), the matching of the three independent modes, enables us to deduce constrained ranges for the mass (M = 8.2 +/- 0.3 Msun) and central hydrogen abundance (X_c = 0.38 +/- 0.02) of theta Oph and to prove the occurrence of core overshooting (alpha_ov = 0.44 +/- 0.07). We also derive an equatorial rotation velocity of 29 +/- 7 km/s. Moreover, we show that t...

  14. GABAB receptor blockade enhances theta and gamma rhythms in the hippocampus of behaving rats.

    Science.gov (United States)

    Leung, L Stan; Shen, Bixia

    2007-01-01

    The participation of GABA(B) receptors in hippocampal EEG generation was studied by intracerebroventricular (icv) and intracerebral infusions of GABA(B) receptor antagonist p-(3-aminopropyl)-p-diethoxymethyl-phosphinic acid (CGP35348) in freely behaving rats. During awake-immobility, icv CGP35348 induced a theta rhythm and increased gamma waves (30-100 Hz) in the hippocampus. The immobility theta peaked at 6-7 Hz and had a theta phase in CA1 stratum radiatum of approximately 160 degrees with reference to the theta at the alveus, when compared with approximately 130 degrees during walking. Immobility theta power peaks at 6-7 Hz was also found in normal rats, and it was detected in 27% of the EEG segments during immobility. Incidence of immobility theta increased to 87.5% after 480 nmol of CGP35348 icv. Muscarinic antagonist scopolamine (5 mg/kg, ip) suppressed the induction of immobility theta and the gamma power increase after icv CGP35348. CGP35348 icv did not significantly change the hippocampal theta power at 7-8 Hz during walking (theta fundamental), but it increased power at 12-15 Hz, at the second harmonic of theta. CGP35348 icv also increased 30-50 Hz gamma power during walking. Medial septal infusion of CGP35348 (12 nmol in 0.4 microl) increased the power and the frequency of the hippocampal theta second harmonic during walking, but did not increase gamma activity. Infusion of CGP35348 (8 nmol in 0.4 microl) in the hippocampus increased the local gamma activity at 30-100 Hz, but did not induce immobility theta or affect the walking theta rhythm. In conclusion, icv GABA(B) receptor blockade increased an atropine-sensitive input that generated an immobility theta rhythm, while GABA(B) receptor blockade of the medial septum increased atropine-resistant theta harmonics possibly generated by apical dendritic spikes. GABA(B) receptor blockade may enhance cognitive task performance by activating hippocampal theta and gamma rhythms in behaving rats.

  15. Theta variation and spatiotemporal scaling along the septotemporal axis of the hippocampus

    Directory of Open Access Journals (Sweden)

    Lauren L Long

    2015-03-01

    Full Text Available Hippocampal theta has been related to locomotor speed, attention, anxiety, sensorimotor integration and memory among other emergent phenomena. One difficulty in understanding the function of theta is that the hippocampus (HPC modulates voluntary behavior at the same time that it processes sensory input. Both functions are correlated with characteristic changes in theta indices. The current review highlights a series of studies examining theta local field potential (LFP signals across the septotemporal or longitudinal axis of the HPC. While the theta signal is coherent throughout the entirety of the HPC, the amplitude, but not the frequency, of theta varies significantly across its three-dimensional expanse. We suggest that the theta signal offers a rich vein of information about how distributed neuronal ensembles support emergent function. Further, we speculate that emergent function across the long axis varies with respect to spatiotemporal scale. Thus, septal hippocampus processes details of the proximal spatiotemporal environment while more temporal aspects process larger spaces and wider time-scales. The degree to which emergent functions are supported by the synchronization of theta across the septotemporal axis is an open question. Our working model is that theta synchrony serves to bind ensembles representing varying resolutions of spatiotemporal information at interdependent septotemporal areas of the HPC. Such synchrony and cooperative interactions along the septotemporal axis likely support memory formation and subsequent consolidation and retrieval.

  16. Non-trivial \\theta-Vacuum Effects in the 2-d O(3) Model

    CERN Document Server

    Bögli, Michael; Pepe, Michele; Wiese, Uwe-Jens

    2011-01-01

    We study \\theta-vacua in the 2-d lattice O(3) model using the standard action and an optimized constraint action with very small cut-off effects, combined with the geometric topological charge. Remarkably, dislocation lattice artifacts do not spoil the non-trivial continuum limit at \\theta\\ non-zero, and there are different continuum theories for each value of \\theta. A very precise Monte Carlo study of the step scaling function indirectly confirms the exact S-matrix of the 2-d O(3) model at \\theta = \\pi.

  17. Nonzero $\\theta_{13}$ in $SO(3) \\rightarrow A_4$ lepton models

    CERN Document Server

    Grossman, Yuval

    2014-01-01

    The simplest neutrino mass models based on $A_4$ symmetry predict $\\theta_{13} = 0$ at tree level, a value that contradicts recent data. We study models that arise from the spontaneous breaking of an $SO(3)$ symmetry to its $A_4$ subgroup, and find two ways to get a nonzero $\\theta_{13}$ at tree level. In the first method extra heavy fields mixed with the charged leptons generate $\\theta_{13}$ of order the ratio between the $A_4$-breaking and the $SO(3)$-breaking scales. In the second method the flavon vacuum alignment is modified, such that it generates $\\theta_{13}$ of order the amount of misalignment.

  18. {\\delta}M Formalism

    CERN Document Server

    Talebian-Ashkezari, Alireza; Abolhasani, Ali Akbar

    2016-01-01

    We study the evolution of the "non-perturbative" metric perturbations in a Bianchi background in the long-wavelength limit. By applying the gradient expansion to the equations of motion we exhibit a generalized "Separate Universe" approach to the cosmological perturbation theory. Having found this consistent separate universe picture, we introduce the "{\\delta}M formalism" for calculating the evolution of the tensor perturbations in anisotropic inflation models in almost similar way as the so-called {\\delta}N formula for the super-horizon dynamics of the curvature perturbations. Likewise its ancestor, {\\delta}N formalism, this new method can substantially reduce the amount of calculations related to the evolution of the tensor modes.

  19. D3-instantons, Mock Theta Series and Twistors

    CERN Document Server

    Alexandrov, Sergei; Pioline, Boris

    2013-01-01

    The D-instanton corrected hypermultiplet moduli space of type II string theory compactified on a Calabi-Yau threefold is known in the type IIA picture to be determined in terms of the generalized Donaldson-Thomas invariants, through a twistorial construction. At the same time, in the mirror type IIB picture, and in the limit where only D3-D1-D(-1)-instanton corrections are retained, it should carry an isometric action of the S-duality group SL(2,Z). We prove that this is the case in the one-instanton approximation, by constructing a holomorphic action of SL(2,Z) on the linearized twistor space. Using the modular invariance of the D4-D2-D0 black hole partition function, we show that the standard Darboux coordinates in twistor space have modular anomalies controlled by period integrals of a Siegel-Narain theta series, which can be canceled by a contact transformation generated by a holomorphic mock theta series.

  20. D3-instantons, mock theta series and twistors

    Science.gov (United States)

    Alexandrov, Sergei; Manschot, Jan; Pioline, Boris

    2013-04-01

    The D-instanton corrected hypermultiplet moduli space of type II string theory compactified on a Calabi-Yau threefold is known in the type IIA picture to be determined in terms of the generalized Donaldson-Thomas invariants, through a twistorial construction. At the same time, in the mirror type IIB picture, and in the limit where only D3-D1-D(-1)-instanton corrections are retained, it should carry an isometric action of the S-duality group SL(2, {Z} ). We prove that this is the case in the one-instanton approximation, by constructing a holomorphic action of SL(2, {Z} ) on the linearized twistor space. Using the modular invariance of the D4-D2-D0 black hole partition function, we show that the standard Darboux coordinates in twistor space have modular anomalies controlled by period integrals of a Siegel-Narain theta series, which can be canceled by a contact transformation generated by a holomorphic mock theta series.

  1. $R^4$ couplings, the fundamental membrane and exceptional theta correspondences

    CERN Document Server

    Pioline, B; Plefka, J; Waldron, A

    2001-01-01

    This letter is an attempt to carry out a first-principle computation in M-theory using the point of view that the eleven-dimensional membrane gives the fundamental degrees of freedom of M-theory. Our aim is to derive the exact BPS $R^4$ couplings in M-theory compactified on a torus $T^{d+1}$ from the toroidal BPS membrane, by pursuing the analogy with the one-loop string theory computation. We exhibit an $Sl(3,\\Zint)$ modular invariance hidden in the light-cone gauge (but obvious in the Polyakov approach), and recover the correct classical spectrum and membrane instantons; the summation measure however is incorrect. It is argued that the correct membrane amplitude should be given by an exceptional theta correspondence lifting $Sl(3,\\Zint)$ modular forms to $\\exc(\\Zint)$ automorphic forms, generalizing the usual theta lift between $Sl(2,\\Zint)$ and $SO(d,d,\\Zint)$ in string theory. The exceptional correspondence $Sl(3)\\times E_{6(6)}\\subset E_{8(8)}$ offers the interesting prospect of solving the membrane smal...

  2. Multimode fiber with z-dependent alpha-value.

    Science.gov (United States)

    Marcuse, D

    1979-07-01

    The width of the impulse response of multimode fibers with power law index profiles depends on the alpha-value of the power law exponent. For constant alpha, optimum pulse width is achievable only in a very narrow range of values centered around alpha = 2 - (12/5)Delta. We show in this paper that the optimum width of the impulse response is achievable for fibers with nonoptimum alpha-values provided alpha varies slowly along the fiber and deviates on average by equal amounts to either side of its (constant) optimum value.

  3. Nuclear receptor corepressor-dependent repression of peroxisome-proliferator-activated receptor delta-mediated transactivation

    DEFF Research Database (Denmark)

    Krogsdam, Anne-M; Nielsen, Curt A F; Neve, Søren

    2002-01-01

    delta-RXR alpha heterodimer bound to an acyl-CoA oxidase (ACO)-type peroxisome-proliferator response element recruited a glutathione S-transferase-NCoR fusion protein in a ligand-independent manner. Contrasting with most other nuclear receptors, PPAR delta was found to interact equally well......The nuclear receptor corepressor (NCoR) was isolated as a peroxisome-proliferator-activated receptor (PPAR) delta interacting protein using the yeast two-hybrid system. NCoR interacted strongly with the ligand-binding domain of PPAR delta, whereas interactions with the ligand-binding domains...

  4. Nuclear receptor corepressor-dependent repression of peroxisome-proliferator-activated receptor delta-mediated transactivation

    DEFF Research Database (Denmark)

    Krogsdam, Anne-M; Nielsen, Curt A F; Neve, Søren

    2002-01-01

    delta-RXR alpha heterodimer bound to an acyl-CoA oxidase (ACO)-type peroxisome-proliferator response element recruited a glutathione S-transferase-NCoR fusion protein in a ligand-independent manner. Contrasting with most other nuclear receptors, PPAR delta was found to interact equally well......The nuclear receptor corepressor (NCoR) was isolated as a peroxisome-proliferator-activated receptor (PPAR) delta interacting protein using the yeast two-hybrid system. NCoR interacted strongly with the ligand-binding domain of PPAR delta, whereas interactions with the ligand-binding domains...

  5. Investigation of thermonuclear $^{18}$Ne($\\alpha$,$p$)$^{21}$Na rate via resonant elastic scattering of $^{21}$Na+$p$

    CERN Document Server

    Zhang, L Y; Parikh, A; Xu, S W; Yamaguchi, H; Kahl, D; Kubono, S; Mohr, P; Hu, J; Ma, P; Chen, S Z; Wakabayashi, Y; Wang, H W; Tian, W D; Chen, R F; Guo, B; Hashimoto, T; Togano, Y; Hayakawa, S; Teranishi, T; Iwasa, N; Yamada, T; Komatsubara, T; Zhang, Y H; Zhou, X H

    2014-01-01

    The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction is thought to be one of the key breakout reactions from the hot CNO cycles to the rp-process in type I x-ray bursts. In this work, the resonant properties of the compound nucleus $^{22}$Mg have been investigated by measuring the resonant elastic scattering of $^{21}$Na+$p$. An 89 MeV $^{21}$Na radioactive beam delivered from the CNS Radioactive Ion Beam Separator bombarded an 8.8 mg/cm$^2$ thick polyethylene (CH$_{2}$)$_{n}$ target. The $^{21}$Na beam intensity was about 2$\\times$10$^{5}$ pps, with a purity of about 70% on target. The recoiled protons were measured at the center-of-mass scattering angles of $\\theta_{c.m.}$$\\approx$175.2${^\\circ}$, 152.2${^\\circ}$, and 150.5${^\\circ}$ by three sets of $\\Delta E$-$E$ telescopes, respectively. The excitation function was obtained with the thick-target method over energies $E_x$($^{22}$Mg)=5.5--9.2 MeV. In total, 23 states above the proton-threshold in $^{22}$Mg were observed, and their resonant parameters were determ...

  6. Increased entorhinal-prefrontal theta synchronization parallels decreased entorhinal-hippocampal theta synchronization during learning and consolidation of associative memory.

    Directory of Open Access Journals (Sweden)

    Kaori eTakehara-Nishiuchi

    2012-01-01

    Full Text Available Memories are thought to be encoded as a distributed representation in the neocortex. The medial prefrontal cortex (mPFC has been shown to support the expression of memories that initially depend on the hippocampus (HPC, yet the mechanisms by which the HPC and mPFC access the distributed representations in the neocortex are unknown. By measuring phase synchronization of local field potential (LFP oscillations, we found that learning initiated changes in neuronal communication of the HPC and mPFC with the lateral entorhinal cortex (LEC, an area that is connected with many other neocortical regions. LFPs were recorded simultaneously from the three brain regions while rats formed an association between an auditory stimulus (CS and eyelid stimulation (US in a trace eyeblink conditioning paradigm, as well as during retention one month following learning. Over the course of learning, theta oscillations in the LEC and mPFC became strongly synchronized following the presentation of the CS on trials in which rats exhibited a conditioned response (CR, and this strengthened synchronization was also observed during retention one month after learning. In contrast, CS-evoked theta synchronization between the LEC and HPC decreased with learning. Our results suggest that the communication between the LEC and mPFC is strengthened with learning whereas the communication between the LEC and HPC is concomitantly weakened, suggesting that enhanced LEC-mPFC communication may be a key process for theoretically-proposed neocortical reorganization accompanying encoding and consolidation of a memory.

  7. Establishing the Thematic Structure and Investigating the most Prominent Theta Roles Used in Sindhi Language

    Directory of Open Access Journals (Sweden)

    Zahid Ali Veesar

    2015-07-01

    Full Text Available This study focuses on the thematic structure of the Sindhi verbs to find theta roles in the Sindhi language. The study tries to answer the research questions; “What are the thematic structures of Sindhi verbs?” and “What are the prominent theta roles in the Sindhi language?” It examines the argument/thematic structure of Sindhi verbs and also finds the theta roles assigned by the Sindhi verbs to their arguments along with the most prominent theta roles used in the Sindhi language. The data come from the two interviews taken from two young native Sindhi speakers, which consist of 2 hours conversation having 1,669 sentences in natural spoken version of the Sindhi language. Towards the end, it has been found that the Sindhi language has certain theta roles which are assigned by the verbs to their arguments in sentences. Each verb phrase in our data is thus examined and studied in detail in terms of Argument/Thematic structure in order to find theta roles in Sindhi language. Thus, in this regard, each verb phrase (in a sentence has been examined with the help of Carnie’s theoretical framework (Thematic Relation and Theta Roles: 2006 in order to find the prominent theta roles in the Sindhi language. The data have been examined and analysed on the basis of the Carnie’s theoretical framework. The study finds that the Sindhi language has all (09 theta roles which have been proposed by Carnie (2006. It has been found that six prominent theta roles out of nine are used prominently in Sindhi. The six prominent theta roles in Sindhi language are: agent, theme, beneficiary, recipient, locative and goal.

  8. On the Analytic Estimation of Radioactive Contamination from Degraded Alphas

    CERN Document Server

    Kadel, Richard W

    2016-01-01

    The high energy spectrum of alpha particles emitted from a single isotope uniformly contaminating a bulk solid has a flat energy spectrum with a high end cutoff energy equal to the maximal alpha kinetic energy ($T_{\\alpha}$) of the decay. In this flat region of the spectrum, we show the surface rate $r_b\\text{\\,(Bq/keV-cm}^{2})$ arising from a bulk alpha contamination $\\rho_b$ (Bq/cm$^3$) from a single isotope is given by $r_b =\\rho_b \\Delta R/ 4 \\Delta E $, where $\\Delta E = E_1-E_2>0\\ $ is the energy interval considered (keV) in the flat region of the spectrum and $\\Delta R = R_2-R_1$, where $R_2$ ($R_1$) is the amount of the bulk material (cm) necessary to degrade the energy of the alpha from $T_{\\alpha}$ to $E_2$ ($E_1$). We compare our calculation to a rate measurement of alphas from $^{147}$Sm, ($15.32\\%\\,\\pm\\,0.03\\%$ of Sm($nat$) and half life of $(1.06\\,\\pm\\,0.01)\\times\\,10^{11} \\text{yr}$, and find good agreement, with the ratio between prediction to measurement of $100.2\\%\\pm 1.6\\%\\,\\text{(stat)}\\pm...

  9. The Niger Delta Crisis

    African Journals Online (AJOL)

    chifaou.amzat

    2013-09-28

    Sep 28, 2013 ... lions de barils par jour à environ 1 million au plus fort de la crise du Delta ... (JTF) between 13 May 2009 and 4 October 2009 (the deadline for embrac- ..... He had just ended his welcome address as the occasion's chairman.

  10. Towards a complete $\\Delta(27) \\times SO(10)$ SUSY GUT

    CERN Document Server

    Björkeroth, Fredrik; Varzielas, Ivo de Medeiros; King, Stephen F

    2015-01-01

    We propose a renormalisable model based on $\\Delta(27)$ family symmetry with an $SO(10)$ grand unified theory (GUT) leading to a novel form of spontaneous geometrical CP violation. The symmetries, including $\\Delta(27)$ and $\\mathbb{Z}_{9} \\times \\mathbb{Z}_{12} \\times \\mathbb{Z}_{4}^{R}$, are broken close to the GUT breaking scale to yield the minimal supersymmetric standard model (MSSM) with the standard R-parity. $SO(10)$ is broken via $SU(5)$ with doublet-triplet splitting achieved by a version of the Dimopoulos-Wilczek (missing VEV) mechanism. Low-scale Yukawa structure is dictated by the coupling of matter to $ \\Delta(27) $ antitriplets $ \\bar{\\phi} $ whose VEVs are aligned in the CSD3 directions by the superpotential. Light physical Majorana neutrinos masses emerge from a specific implementation of the seesaw mechanism within $SO(10)$. The model predicts a normal neutrino mass hierarchy with the best-fit lightest neutrino mass $ m_1 = 0.13 $ meV and the PMNS mixing parameters $\\theta^l_{13} \\approx 8.3...

  11. $\\alpha_s$ review (2016)

    CERN Document Server

    d'Enterria, David

    2016-01-01

    The current world-average of the strong coupling at the Z pole mass, $\\alpha_s(m^2_{Z}) = 0.1181 \\pm 0.0013$, is obtained from a comparison of perturbative QCD calculations computed, at least, at next-to-next-to-leading-order accuracy, to a set of 6 groups of experimental observables: (i) lattice QCD "data", (ii) $\\tau$ hadronic decays, (iii) proton structure functions, (iv) event shapes and jet rates in $e^+e^-$ collisions, (v) Z boson hadronic decays, and (vi) top-quark cross sections in p-p collisions. In addition, at least 8 other $\\alpha_s$ extractions, usually with a lower level of theoretical and/or experimental precision today, have been proposed: pion, $\\Upsilon$, W hadronic decays; soft and hard fragmentation functions; jets cross sections in pp, e-p and $\\gamma$-p collisions; and photon F$_2$ structure function in $\\gamma\\,\\gamma$ collisions. These 14 $\\alpha_s$ determinations are reviewed, and the perspectives of reduction of their present uncertainties are discussed.

  12. Patterns of coupled theta activity in amygdala-hippocampal-prefrontal cortical circuits during fear extinction.

    Directory of Open Access Journals (Sweden)

    Jörg Lesting

    Full Text Available Signals related to fear memory and extinction are processed within brain pathways involving the lateral amygdala (LA for formation of aversive stimulus associations, the CA1 area of the hippocampus for context-dependent modulation of these associations, and the infralimbic region of the medial prefrontal cortex (mPFC for extinction processes. While many studies have addressed the contribution of each of these modules individually, little is known about their interactions and how they function as an integrated system. Here we show, by combining multiple site local field potential (LFP and unit recordings in freely behaving mice in a fear conditioning paradigm, that theta oscillations may provide a means for temporally and functionally connecting these modules. Theta oscillations occurred with high specificity in the CA1-LA-mPFC network. Theta coupling increased between all areas during retrieval of conditioned fear, and declined during extinction learning. During extinction recall, theta coupling partly rebounded in LA-mPFC and CA1-mPFC, and remained at a low level in CA1-LA. Interfering with theta coupling through local electrical microstimulation in CA1-LA affected conditioned fear and extinction recall depending on theta phase. These results support the hypothesis that theta coupling provides a means for inter-areal coordination in conditioned behavioral responsiveness. More specifically, theta oscillations seem to contribute to a population code indicating conditioned stimuli during recall of fear memory before and after extinction.

  13. Frontal and rostral anterior cingulate (rACC) theta EEG in depression: implications for treatment outcome?

    NARCIS (Netherlands)

    Arns, M.W.; Etkin, A.; Hegerl, U.; Williams, L.M.; DeBattista, C.; Palmer, D.M.; Fitzgerald, P.B.; Harris, A.; deBeuss, R.; Gordon, E.

    2015-01-01

    In major depressive disorder (MDD), elevated theta current density in the rostral anterior cingulate (rACC), as estimated by source localization of scalp-recorded electroencenphalogram (EEG), has been associated with response to antidepressant treatments, whereas elevated frontal theta has been link

  14. Theta Function Identities Associated with Ramanujan's Modular Equations of Degree 15

    Indian Academy of Sciences (India)

    Rupam Barman; Nayandeep Deka Baruah

    2010-06-01

    We present alternative proofs of some of Ramanujan’s theta function identities associated with the modular equations of composite degree 15. Along the way we also find some new theta-function identities. We also give simple proofs of his modular equations of degree 15.

  15. Theta dynamics in rat: speed and acceleration across the Septotemporal axis.

    Directory of Open Access Journals (Sweden)

    Lauren L Long

    Full Text Available Theta (6-12 Hz rhythmicity in the local field potential (LFP reflects a clocking mechanism that brings physically isolated neurons together in time, allowing for the integration and segregation of distributed cell assemblies. Variation in the theta signal has been linked to locomotor speed, sensorimotor integration as well as cognitive processing. Previously, we have characterized the relationship between locomotor speed and theta power and how that relationship varies across the septotemporal (long axis of the hippocampus (HPC. The current study investigated the relationship between whole body acceleration, deceleration and theta indices at CA1 and dentate gyrus (DG sites along the septotemporal axis of the HPC in rats. Results indicate that whole body acceleration and deceleration predicts a significant amount of variability in the theta signal beyond variation in locomotor speed. Furthermore, deceleration was more predictive of variation in theta amplitude as compared to acceleration as rats traversed a linear track. Such findings highlight key variables that systematically predict the variability in the theta signal across the long axis of the HPC. A better understanding of the relative contribution of these quantifiable variables and their variation as a function of experience and environmental conditions should facilitate our understanding of the relationship between theta and sensorimotor/cognitive functions.

  16. Theta dynamics in rat: speed and acceleration across the Septotemporal axis.

    Science.gov (United States)

    Long, Lauren L; Hinman, James R; Chen, Chi-Ming; Escabi, Monty A; Chrobak, James J

    2014-01-01

    Theta (6-12 Hz) rhythmicity in the local field potential (LFP) reflects a clocking mechanism that brings physically isolated neurons together in time, allowing for the integration and segregation of distributed cell assemblies. Variation in the theta signal has been linked to locomotor speed, sensorimotor integration as well as cognitive processing. Previously, we have characterized the relationship between locomotor speed and theta power and how that relationship varies across the septotemporal (long) axis of the hippocampus (HPC). The current study investigated the relationship between whole body acceleration, deceleration and theta indices at CA1 and dentate gyrus (DG) sites along the septotemporal axis of the HPC in rats. Results indicate that whole body acceleration and deceleration predicts a significant amount of variability in the theta signal beyond variation in locomotor speed. Furthermore, deceleration was more predictive of variation in theta amplitude as compared to acceleration as rats traversed a linear track. Such findings highlight key variables that systematically predict the variability in the theta signal across the long axis of the HPC. A better understanding of the relative contribution of these quantifiable variables and their variation as a function of experience and environmental conditions should facilitate our understanding of the relationship between theta and sensorimotor/cognitive functions.

  17. Resting-state EEG theta activity and risk learning: sensitivity to reward or punishment?

    NARCIS (Netherlands)

    Massar, S.A.A.; Kenemans, J.L.; Schutter, D.J.L.G.

    2014-01-01

    Increased theta (4-7 Hz)-beta.(13-30 Hz) power ratio in resting state electroencephalography (EEG) has been associated with risky disadvantageous decision making and with impaired reinforcement learning. However, the specific contributions of theta and beta power in risky decision making remain uncl

  18. Determination of absorbed dose in water at the reference point d(r0, theta0) for an 192Ir HDR brachytherapy source using a Fricke system.

    Science.gov (United States)

    Austerlitz, C; Mota, H C; Sempau, J; Benhabib, S M; Campos, D; Allison, R; DeAlmeida, C E; Zhu, D; Sibata, C H

    2008-12-01

    A ring-shaped Fricke device was developed to measure the absolute dose on the transverse bisector of a 192Ir high dose rate (HDR) source at 1 cm from its center in water, D(r0, theta0). It consists of a polymethylmethacrylate (PMMA) rod (axial axis) with a cylindrical cavity at its center to insert the 192Ir radioactive source. A ring cavity around the source with 1.5 mm thickness and 5 mm height is centered at 1 cm from the central axis of the source. This ring cavity is etched in a disk shaped base with 2.65 cm diameter and 0.90 cm thickness. The cavity has a wall around it 0.25 cm thick. This ring is filled with Fricke solution, sealed, and the whole assembly is immersed in water during irradiations. The device takes advantage of the cylindrical geometry to measure D(r0, theta0). Irradiations were performed with a Nucletron microselectron HDR unit loaded with an 192Ir Alpha Omega radioactive source. A Spectronic 1001 spectrophotometer was used to measure the optical absorbance using a 1 mL quartz cuvette with 1.00 cm light pathlength. The PENELOPE Monte Carlo code (MC) was utilized to simulate the Fricke device and the 192Ir Alpha Omega source in detail to calculate the perturbation introduced by the PMMA material. A NIST traceable calibrated well type ionization chamber was used to determine the air-kerma strength, and a published dose-rate constant was used to determine the dose rate at the reference point. The time to deliver 30.00 Gy to the reference point was calculated. This absorbed dose was then compared to the absorbed dose measured by the Fricke solution. Based on MC simulation, the PMMA of the Fricke device increases the D(r0, theta0) by 2.0%. Applying the corresponding correction factor, the D(r0, theta0) value assessed with the Fricke device agrees within 2.0% with the expected value with a total combined uncertainty of 3.43% (k=1). The Fricke device provides a promising method towards calibration of brachytherapy radiation sources in terms of D(r0

  19. Laser--plasma interaction in a theta-pinch geometry

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, W.T.

    1978-06-01

    Prompt stimulated Brillouin scatter (SBS) is studied in an experiment wherein a high power, pulsed CO/sub 2/ laser irradiates an independently produced, theta-pinch plasma. SBS does not significantly affect laser heating of the plasma. Measurements of density profiles and temperature histories permitted examination of laser refraction, local heating and net absorption. Refractive containment of the CO/sub 2/ laser beam by an on-axis density minimum was observed at early times during the laser pulse. However, refractive containment was lost at late times due to the diffusive loss of the density minimum. Classical modeling of the expected heating required ''bleached'' absorption to account for the observed heating. A plasma absorptivity of approximately 46% was inferred from calorimetry measurements at 250 mtorr fill pressure. These results confirm that classical heating and refraction dominated the laser-plasma interaction.

  20. Determination of $sin^{2}\\theta_W$ using $\

    CERN Document Server

    Haider, H; Athar, M Sajjad

    2013-01-01

    We have studied nonisoscalarity and medium effects in the extraction of weak mixing angle using Paschos and Wolfenstein relation in the iron nucleus. Paschos and Wolfenstein(PW) relation is valid for an isoscalar target. We have modified the PW relation for nonisoscalar target as well as incorporated the medium effects like Pauli blocking, Fermi motion, nuclear binding energy and pion rho cloud contributions. In our calculations we have used the relativistic nuclear spectral function which includes nucleon correlations. Finally local density approximation is applied to translate the numerical results to the finite nuclei. We have studied the dependence of $sin^{2}\\theta_W$ on Bjorken variables $x$ and $y$, four momentum transfer square ($Q^2$), energy of the neutrino and antineutrino, and effect of excess neutrons over protons in the nuclear target.

  1. Small Neutrino Masses from Gravitational $\\theta$-Term

    CERN Document Server

    Dvali, Gia

    2016-01-01

    We present how a neutrino condensate and small neutrino masses emerge from a topological formulation of gravitational anomaly. We first recapitulate how a gravitational $\\theta$-term leads to the emergence of a new bound neutrino state analogous to the $\\eta'$ meson of QCD. Then we show the consequent formation of a neutrino vacuum condensate which effectively generates small neutrino masses. Afterwards we outline numerous phenomenological consequences of our model. The cosmological neutrino mass bound vanishes since we predict the neutrinos to be massless until the very late universe, $T\\sim {\\rm meV}$. Coherent radiation of new light particles in the neutrino sector could be detected in future precision experiments. The current cosmological neutrino background consists only of the lightest neutrinos which are either bound up, form a superfluid, or completely annihilate into massless bosons. The deviations from an equal flavor rate due to enhanced neutrino decays in extraterrestrial neutrino fluxes can be ob...

  2. Energy transfer efficiency of a spherical theta-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Teske, Christian; Fedjuschenko, Andreas; Jacoby, Joachim; Schweizer, Waldemar [Institut fuer Angewandte Physik, Frankfurt am Main (Germany)

    2010-07-01

    A spherical theta-pinch device for VUV generation and plasma stripper applications with an operating frequency of 12 kHz has been developed. The setup consists of a series resonance circuit with a load capacitance of 27 {mu}F and a large diameter induction coil surrounding a spherical discharge vessel with a discharge volume of 4000 ml. First measurements have been made to evaluate the transfer efficiency of the pulsed inductive discharge in Argon with 2.8% Hydrogen at gas pressures from 0.6 Pa up to 100 Pa at load voltages from 4 kV to 8 kV. Pulsed coil currents reached a maximum value of 18 kA with current rise times of 2 kA/mys while achieving a maximum energy transfer efficiency of 85% between the driving circuit and the plasma. Pulsed power peak values inside the plasma reached more than 2 MW.

  3. Quark splitting in non-trivial \\theta-vacuum

    CERN Document Server

    Xing, Hongxi; Yuan, Feng

    2010-01-01

    Quark splitting in non-trivial $\\theta$-vacuum with a given helicity is investigated in pQCD with a modified quark propagator. We found that the quark splitting functions were modified by the presence of a topologically non-trivial QCD background field, though there is no explicit helicity flip associated with the radiative processes. The interaction with the topological non-trivial field leads to the degeneracy of the quark splitting functions for left- and right-handed quarks. Such degeneracy can lead to imbalance of left- and right-handed quarks in quark jet showers. We also discuss phenomenological consequences of such imbalance if there exists non-trivial topological gluon field configuration in heavy-ion collisions.

  4. Higher Spin Fields in Siegel Space, Currents and Theta Functions

    CERN Document Server

    Gelfond, O A

    2009-01-01

    Dynamics of four-dimensional massless fields of all spins is formulated in the Siegel space of complex $4\\times 4$ symmetric matrices. It is shown that the unfolded equations of free massless fields, that have a form of multidimensional Schrodinger equations, naturally distinguish between positive- and negative-frequency solutions of relativistic field equations, i.e. particles and antiparticles. Multidimensional Riemann theta functions are shown to solve massless field equations in the Siegel space. We establish the correspondence between conserved higher-spin currents in four-dimensional Minkowski space and those in the ten-dimensional matrix space. It is shown that global symmetry parameters of the current in the matrix space should be singular to reproduce a nonzero current in Minkowski space. The $\\D$-function integral evolution formulae for 4d massless fields in the Fock-Siegel space are obtained. The generalization of the proposed scheme to higher dimensions and systems of higher ranks is considered.

  5. Fermion Wavefunctions in Magnetized branes Theta identities and Yukawa couplings

    CERN Document Server

    Antoniadis, Ignatios; Panda, Binata

    2009-01-01

    Computation of Yukawa couplings, determining superpotentials as well as the Kähler metric, with oblique (non-commuting) fluxes in magnetized brane constructions is an interesting unresolved issue, in view of the importance of such fluxes for obtaining phenomenologically viable models. In order to perform this task, fermion (scalar) wavefunctions on toroidally compactified spaces are presented for general fluxes, parameterized by Hermitian matrices with eigenvalues of arbitrary signatures. We also give explicit mappings among fermion wavefunctions, of different internal chiralities on the tori, which interchange the role of the flux components with the complex structure of the torus. By evaluating the overlap integral of the wavefunctions, we give the expressions for Yukawa couplings among chiral multiplets arising from an arbitrary set of branes (or their orientifold images). The method is based on constructing certain mathematical identities for general Riemann theta functions with matrix valued modular par...

  6. Modelling repeatedly flaring delta-sunspots

    CERN Document Server

    Chatterjee, Piyali; Carlsson, Mats

    2016-01-01

    Active regions (AR) appearing on the surface of the Sun are classified into $\\alpha$, $\\beta$, $\\gamma$, and $\\delta$ by the rules of the Mount Wilson Observatory, California on the basis of their topological complexity. Amongst these, the $\\delta$-sunspots are known to be super-active and produce the most X-ray flares. Here, we present results from a simulation of the Sun by mimicking the upper layers and the corona, but starting at a more primitive stage than any earlier treatment. We find that this initial state consisting of only a thin sub-photospheric magnetic sheet breaks into multiple flux-tubes which evolve into a colliding-merging system of spots of opposite polarity upon surface emergence, similar to those often seen on the Sun. The simulation goes on to produce many exotic $\\delta$-sunspot associated phenomena: repeated flaring in the range of typical solar flare energy release and ejective helical flux ropes with embedded cool-dense plasma filaments resembling solar coronal mass ejections.

  7. Metastability and Delta-Phase Retention in Plutonium Alloys Final Report of LDRD Project 01-ERD-029

    Energy Technology Data Exchange (ETDEWEB)

    Wong, J; Schwartz, A J; Blobaum, K M; Krenn, C R; Wall, M A; Wolfer, W G; Haslam, J J; Moore, K T

    2004-02-11

    The {delta} to {alpha}' phase transformation in Pu-Ga alloys is intriguing for both scientific and technological reasons. On cooling, the ductile fcc {delta}-phase transforms martensitically to the brittle monoclinic {alpha}'-phase at approximately -120 C (depending on composition). This exothermic transformation involves a 20% volume contraction and a significant increase in resistivity. The reversion of {alpha}' to {delta} involves a large temperature hysteresis beginning just above room temperature. In an attempt to better understand the underlying thermodynamics and kinetics responsible for these unusual features, we have investigated the {delta} {leftrightarrow} {alpha}' phase transformations in a Pu-0.6 wt% Ga alloy using a combination of experimental and modeling techniques.

  8. Environmental novelty elicits a later theta phase of firing in CA1 but not subiculum.

    Science.gov (United States)

    Lever, Colin; Burton, Stephen; Jeewajee, Ali; Wills, Thomas J; Cacucci, Francesca; Burgess, Neil; O'Keefe, John

    2010-02-01

    The mechanism supporting the role of the hippocampal formation in novelty detection remains controversial. A comparator function has been variously ascribed to CA1 or subiculum, whereas the theta rhythm has been suggested to separate neural firing into encoding and retrieval phases. We investigated theta phase of firing in principal cells in subiculum and CA1 as rats foraged in familiar and novel environments. We found that the preferred theta phase of firing in CA1, but not subiculum, was shifted to a later phase of the theta cycle during environmental novelty. Furthermore, the amount of phase shift elicited by environmental change correlated with the extent of place cell remapping in CA1. Our results support a relationship between theta phase and novelty-induced plasticity in CA1.

  9. Search for $\\Theta^{++}$ Pentaquarks in the Exclusive Reaction $\\gamma p\\to K^+K^-p$

    CERN Document Server

    Kubarovski, V; De Vita, R; Goett, J; Guo, L; Mutchler, G S; Stoler, P; Weygand, D P; Ambrozewicz, P; Anghinolfi, M; Asryan, G; Avakian, H; Bagdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Batourine, V; Bedlinskiy, I; Bellis, M; Benmouna, N; Berman, B L; Biselli, A S; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Burkert, V D; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Chen, S; Clinton, E; Cole, P L; Collins, P; Coltharp, P; Crabb, D; Crannell, H; Credé, V; Cummings, J P; De Masi, R; Dale, D; De Sanctis, E; Degtyarenko, P V; Deur, A; Dharmawardane, K V; Djalali, C; Dodge, G E; Donnelly, J; Doughty, D; Dugger, M; Dzyubak, O P; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Eugenio, P; Fedotov, G; Funsten, H; Gabrielyan, M Y; Gan, L; Garçon, M; Gasparian, A; Gavalian, G; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Glamazdin, O; Goetz, J T; Golovach, E; Gonenc, A; Gordon, C I O; Gothe, R W; Griffioen, K A; Guidal, M; Guler, N; Gyurjyan, V; Hadjidakis, C; Hafidi, K; Hakobyan, R S; Hardie, J; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Ito, M M; Jenkins, D; Jo, H S; Joo, K; Jüngst, H G; Kellie, J D; Khandaker, M; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Kossov, M; Kramer, L H; Kühn, J; Kuhn, S E; Kuleshov, S V; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Lee, T; Li, J; Livingston, K; Lü, H; MacCormick, M; Markov, N; McKinnon, B; Mecking, B A; Melone, J J; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Minehart, R C; Mirazita, M; Miskimen, R; Mochalov, V; Mokeev, V; Morand, L; Morrow, S A; Moteabbed, M; Nadel-Turonski, P; Nakagawa, I; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niroula, M R; Niyazov, R A; Nozar, M; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E; Paterson, C; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O I; Pozdniakov, S; Price, J W; Prok, Y; Protopopescu, D; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Ronchetti, F; Rosner, G; Rossi, P; Sabatie, F; Salgado, C; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Sharabyan, Yu G; Shvedunov, N V; Smith, E S; Smith, L C; Sober, D I; Stavinsky, A V; Stepanyan, S; Stokes, B E; Strakovsky, I I; Strauch, S; Taiuti, M; Tedeschi, D J; Teymurazyan, A; Thoma, U; Tkabladze, A; Tkachenko, S I; Todor, L; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Weinstein, L B; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Zana, L; Zhang, J; Zhao, B

    2006-01-01

    The reaction $\\gamma p \\to pK^+K^-$ was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a $\\Theta^{++}$ pentaquark, a narrow doubly charged baryon state having strangeness S=+1 and isospin I=1, in the $pK^+$ invariant mass spectrum. No statistically significant evidence of a $\\Theta^{++}$ was found. Upper limits on the total and differential production cross section for the reaction $\\gamma p \\to K^-\\Theta^{++}$ were obtained in the mass range from 1.5 to 2.0 GeV/c$^2$, with an upper limit of about 0.15 nb, 95% C.L. for a narrow resonance with a mass $M_{\\Theta^{++}}=1.54$ GeV/c$^2$. This result places a very stringent upper limit on the $\\Theta^{++}$ width.

  10. Theta frontoparietal connectivity associated with proactive and reactive cognitive control processes.

    Science.gov (United States)

    Cooper, Patrick S; Wong, Aaron S W; Fulham, W Ross; Thienel, Renate; Mansfield, Elise; Michie, Patricia T; Karayanidis, Frini

    2015-03-01

    Cognitive control involves both proactive and reactive processes. Paradigms that rely on reactive control have shown that frontoparietal oscillatory synchronization in the theta frequency band is associated with interference control. This study examines whether proactive control is also associated with connectivity in the same frontoparietal theta network or involves a distinct neural signature. A task-switching paradigm was used to differentiate between proactive and reactive control processes, involved in preparing to switch or repeat a task and resolving post-target interference, respectively. We confirm that reactive control is associated with frontoparietal theta connectivity. Importantly, we show that proactive control is also associated with theta band oscillatory synchronization but in a different frontoparietal network. These findings support the existence of distinct proactive and reactive cognitive control processes that activate different theta frontoparietal oscillatory networks.

  11. Observation of the positive-strangeness pentaquark $\\Theta^+$ in photoproduction with the SAPHIR detector at ELSA

    CERN Document Server

    Barth, J; Ernst, J; Glander, K H; Hannappel, J; Jöpen, N; Kalinowsky, H; Klein, F; Klempt, E; Lawall, R; Link, J; Menze, D W; Neuerburg, W; Ostrick, M; Paul, E; Van Pee, H; Schulday, I; Schwille, W J; Wiegers, B; Wieland, F W; Wisskirchen, J; Wu, C

    2003-01-01

    The positive--strangeness baryon resonance $\\Theta^+$ is observed in photoproduction of the $\\rm nK^+K^0_s$ final state with the SAPHIR detector at the Bonn ELectron Stretcher Accelerator ELSA. It is seen as a peak in the $\\rm nK^+$ invariant mass distribution with a $4.8\\sigma$ confidence level. We find a mass $\\rm M_{\\Theta^+} = 1540\\pm 4\\pm 2$ MeV and an upper limit of the width $\\rm \\Gamma_{\\Theta^+} < 25$ MeV at 90% c.l. The photoproduction cross section for $\\rm\\bar K^0\\Theta^+$ is in the order of 300 nb. From the absence of a signal in the $\\rm pK^+$ invariant mass distribution in $\\rm\\gamma p\\to pK^+K^-$ at the expected strength we conclude that the $\\Theta^+$ must be isoscalar.

  12. DELTAS: A new Global Delta Sustainability Initiative (Invited)

    Science.gov (United States)

    Foufoula-Georgiou, E.

    2013-12-01

    Deltas are economic and environmental hotspots, food baskets for many nations, home to a large part of the world population, and hosts of exceptional biodiversity and rich ecosystems. Deltas, being at the land-water interface, are international, regional, and local transport hubs, thus providing the basis for intense economic activities. Yet, deltas are deteriorating at an alarming rate as 'victims' of human actions (e.g. water and sediment reduction due to upstream basin development), climatic impacts (e.g. sea level rise and flooding from rivers and intense tropical storms), and local exploration (e.g. sand or aggregates, groundwater and hydrocarbon extraction). Although many efforts exist on individual deltas around the world, a comprehensive global delta sustainability initiative that promotes awareness, science integration, data and knowledge sharing, and development of decision support tools for an effective dialogue between scientists, managers and policy makers is lacking. Recently, the international scientific community proposed to establish the International Year of Deltas (IYD) to serve as the beginning of such a Global Delta Sustainability Initiative. The IYD was proposed as a year to: (1) increase awareness and attention to the value and vulnerability of deltas worldwide; (2) promote and enhance international and regional cooperation at the scientific, policy, and stakeholder level; and (3) serve as a launching pad for a 10-year committed effort to understand deltas as complex socio-ecological systems and ensure preparedness in protecting and restoring them in a rapidly changing environment. In this talk, the vision for such an international coordinated effort on delta sustainability will be presented as developed by a large number of international experts and recently funded through the Belmont Forum International Opportunities Fund. Participating countries include: U.S., France, Germany, U.K., India, Japan, Netherlands, Norway, Brazil, Bangladesh

  13. A computational predictor of human episodic memory based on a theta phase precession network.

    Directory of Open Access Journals (Sweden)

    Naoyuki Sato

    Full Text Available In the rodent hippocampus, a phase precession phenomena of place cell firing with the local field potential (LFP theta is called "theta phase precession" and is considered to contribute to memory formation with spike time dependent plasticity (STDP. On the other hand, in the primate hippocampus, the existence of theta phase precession is unclear. Our computational studies have demonstrated that theta phase precession dynamics could contribute to primate-hippocampal dependent memory formation, such as object-place association memory. In this paper, we evaluate human theta phase precession by using a theory-experiment combined analysis. Human memory recall of object-place associations was analyzed by an individual hippocampal network simulated by theta phase precession dynamics of human eye movement and EEG data during memory encoding. It was found that the computational recall of the resultant network is significantly correlated with human memory recall performance, while other computational predictors without theta phase precession are not significantly correlated with subsequent memory recall. Moreover the correlation is larger than the correlation between human recall and traditional experimental predictors. These results indicate that theta phase precession dynamics are necessary for the better prediction of human recall performance with eye movement and EEG data. In this analysis, theta phase precession dynamics appear useful for the extraction of memory-dependent components from the spatio-temporal pattern of eye movement and EEG data as an associative network. Theta phase precession may be a common neural dynamic between rodents and humans for the formation of environmental memories.

  14. Movement-related theta rhythm in humans: coordinating self-directed hippocampal learning.

    Science.gov (United States)

    Kaplan, Raphael; Doeller, Christian F; Barnes, Gareth R; Litvak, Vladimir; Düzel, Emrah; Bandettini, Peter A; Burgess, Neil

    2012-01-01

    The hippocampus is crucial for episodic or declarative memory and the theta rhythm has been implicated in mnemonic processing, but the functional contribution of theta to memory remains the subject of intense speculation. Recent evidence suggests that the hippocampus might function as a network hub for volitional learning. In contrast to human experiments, electrophysiological recordings in the hippocampus of behaving rodents are dominated by theta oscillations reflecting volitional movement, which has been linked to spatial exploration and encoding. This literature makes the surprising cross-species prediction that the human hippocampal theta rhythm supports memory by coordinating exploratory movements in the service of self-directed learning. We examined the links between theta, spatial exploration, and memory encoding by designing an interactive human spatial navigation paradigm combined with multimodal neuroimaging. We used both non-invasive whole-head Magnetoencephalography (MEG) to look at theta oscillations and Functional Magnetic Resonance Imaging (fMRI) to look at brain regions associated with volitional movement and learning. We found that theta power increases during the self-initiation of virtual movement, additionally correlating with subsequent memory performance and environmental familiarity. Performance-related hippocampal theta increases were observed during a static pre-navigation retrieval phase, where planning for subsequent navigation occurred. Furthermore, periods of the task showing movement-related theta increases showed decreased fMRI activity in the parahippocampus and increased activity in the hippocampus and other brain regions that strikingly overlap with the previously observed volitional learning network (the reverse pattern was seen for stationary periods). These fMRI changes also correlated with participant's performance. Our findings suggest that the human hippocampal theta rhythm supports memory by coordinating exploratory

  15. Brain oscillatory activity during motor preparation: Effect of directional uncertainty on beta, but not alpha, frequency band

    Directory of Open Access Journals (Sweden)

    Charidimos eTzagarakis

    2015-07-01

    Full Text Available In time-constraint activities, such as sports, it is advantageous to be prepared to act even before knowing precisely what action will be needed. Here, we studied the relation between neural oscillations during motor preparation and amount of uncertainty about the direction of the upcoming target. Ten right-handed volunteers participated in a cued center-out task. A brief visual cue identified the region of space in which the target would appear. Three cue sizes were used to vary the amount of information about the direction of the upcoming target. The target appeared at a random location within the region indicated by the cue, and the participants moved a joystick-controlled cursor towards it. Time-frequency analyses showed phasic increases of power in low (delta/theta: 30 Hz frequency-bands in relation to the onset of visual stimuli and of the motor response. More importantly in regard to motor preparation, there was a tonic reduction of power in the alpha (8-12 Hz and beta (14-30 Hz bands during the period between cue presentation and target onset. During motor preparation, the main source of change of power of the alpha band was localized over the contralateral sensorimotor region and both parietal cortices, whereas for the beta-band the main source was the contralateral sensorimotor region. During cue presentation, the reduction of power of the alpha-band in the occipital lobe showed a brief differentiation of condition: the wider the visual cue, the more the power of the alpha-band decreased. However during motor preparation, only the power of the beta-band was dependent on directional uncertainty: the less the directional uncertainty, the more the power of the beta-band decreased. In conclusion, the results indicate that the power in the alpha-band is associated briefly with cue size, but is otherwise an undifferentiated indication of neural activation, whereas the power of the beta-band reflects the level of motor preparation.

  16. Age-related changes of frontal-midline theta is predictive of efficient memory maintenance.

    Science.gov (United States)

    Kardos, Z; Tóth, B; Boha, R; File, B; Molnár, M

    2014-07-25

    Frontal areas are thought to be the coordinators of working memory processes by controlling other brain areas reflected by oscillatory activities like frontal-midline theta (4-7 Hz). With aging substantial changes can be observed in the frontal brain areas, presumably leading to age-associated changes in cortical correlates of cognitive functioning. The present study aimed to test whether altered frontal-midline theta dynamics during working memory maintenance may underlie the capacity deficits observed in older adults. 33-channel EEG was recorded in young (18-26 years, N=20) and old (60-71 years, N=16) adults during the retention period of a visual delayed match-to-sample task, in which they had to maintain arrays of 3 or 5 colored squares. An additional visual odd-ball task was used to be able to measure the electrophysiological indices of sustained attentional processes. Old participants showed reduced frontal theta activity during both tasks compared to the young group. In the young memory maintenance-related frontal-midline theta activity was shown to be sensitive both to the increased memory demands and to efficient subsequent memory performance, whereas the old adults showed no such task-related difference in the frontal theta activity. The decrease of frontal-midline theta activity in the old group indicates that cerebral aging may alter the cortical circuitries of theta dynamics, thereby leading to age-associated decline of working memory maintenance function.

  17. Frontal Theta Dynamics during Response Conflict in Long-Term Mindfulness Meditators

    Science.gov (United States)

    Jo, Han-Gue; Malinowski, Peter; Schmidt, Stefan

    2017-01-01

    Mindfulness meditators often show greater efficiency in resolving response conflicts than non-meditators. However, the neural mechanisms underlying the improved behavioral efficiency are unclear. Here, we investigated frontal theta dynamics—a neural mechanism involved in cognitive control processes—in long-term mindfulness meditators. The dynamics of EEG theta oscillations (4–8 Hz) recorded over the medial frontal cortex (MFC) were examined in terms of their power (MFC theta power) and their functional connectivity with other brain areas (the MFC-centered theta network). Using a flanker-type paradigm, EEG data were obtained from 22 long-term mindfulness meditators and compared to those from 23 matched controls without meditation experience. Meditators showed more efficient cognitive control after conflicts, evidenced by fewer error responses irrespective of response timing. Furthermore, meditators exhibited enhanced conflict modulations of the MFC-centered theta network shortly before the response, in particular for the functional connection between the MFC and the motor cortex. In contrast, MFC theta power was comparable between groups. These results suggest that the higher behavioral efficiency after conflicts in mindfulness meditators could be a function of increased engagement to control the motor system in association with the MFC-centered theta network. PMID:28638334

  18. Frontal Theta Dynamics during Response Conflict in Long-Term Mindfulness Meditators.

    Science.gov (United States)

    Jo, Han-Gue; Malinowski, Peter; Schmidt, Stefan

    2017-01-01

    Mindfulness meditators often show greater efficiency in resolving response conflicts than non-meditators. However, the neural mechanisms underlying the improved behavioral efficiency are unclear. Here, we investigated frontal theta dynamics-a neural mechanism involved in cognitive control processes-in long-term mindfulness meditators. The dynamics of EEG theta oscillations (4-8 Hz) recorded over the medial frontal cortex (MFC) were examined in terms of their power (MFC theta power) and their functional connectivity with other brain areas (the MFC-centered theta network). Using a flanker-type paradigm, EEG data were obtained from 22 long-term mindfulness meditators and compared to those from 23 matched controls without meditation experience. Meditators showed more efficient cognitive control after conflicts, evidenced by fewer error responses irrespective of response timing. Furthermore, meditators exhibited enhanced conflict modulations of the MFC-centered theta network shortly before the response, in particular for the functional connection between the MFC and the motor cortex. In contrast, MFC theta power was comparable between groups. These results suggest that the higher behavioral efficiency after conflicts in mindfulness meditators could be a function of increased engagement to control the motor system in association with the MFC-centered theta network.

  19. Resting-state EEG theta activity and risk learning: sensitivity to reward or punishment?

    Science.gov (United States)

    Massar, Stijn A A; Kenemans, J Leon; Schutter, Dennis J L G

    2014-03-01

    Increased theta (4-7 Hz)-beta (13-30 Hz) power ratio in resting state electroencephalography (EEG) has been associated with risky disadvantageous decision making and with impaired reinforcement learning. However, the specific contributions of theta and beta power in risky decision making remain unclear. The first aim of the present study was to replicate the earlier found relationship and examine the specific contributions of theta and beta power in risky decision making using the Iowa Gambling Task. The second aim of the study was to examine whether the relation were associated with differences in reward or punishment sensitivity. We replicated the earlier found relationship by showing a positive association between theta/beta ratio and risky decision making. This correlation was mainly driven by theta oscillations. Furthermore, theta power correlated with reward motivated learning, but not with punishment learning. The present results replicate and extend earlier findings by providing novel insights into the relation between thetabeta ratios and risky decision making. Specifically, findings show that resting-state theta activity is correlated with reinforcement learning, and that this association may be explained by differences in reward sensitivity.

  20. Investigating the parity of the exotic Theta^+ baryon from the kaon photoproduction

    CERN Document Server

    Yu, B G; Ji, C R; Yu, Byung Geel; Choi, Tae Keun; Ji, Chueng-Ryong

    2003-01-01

    Based on the hadronic model with an improved version of gauge prescription including form factors, we investigate the possibility of determining the parity state of $\\Theta^+$ baryon using photon induced processes, $\\gamma n\\to K^- \\Theta^+$, $\\gamma p\\to \\bar{K}^0 \\Theta^+$. The total and differential cross sections are simulated in two versions of pseudovector(PV) and pseudoscalar(PS) coupling schemes for $KN\\Theta$ interaction and the results are reported both on the positive and negative parity states of $\\Theta^+$ baryon. It is found that in both schemes the total cross sections from the neutron are larger than those from the proton. In particular, not only the cross sections of the positive parity $\\Theta^+$ production but also those of the negative parity $\\Theta^+$ production are found to be comparable to the cross section observed in the SAPHIR experiment. Our analysis suggests that the observation of angular distribution rather than just the total cross section in the photoproduction processes may b...

  1. Fast entrainment of human electroencephalogram to a theta-band photic flicker during successful memory encoding

    Directory of Open Access Journals (Sweden)

    Naoyuki eSato

    2013-05-01

    Full Text Available Theta band power (4-8Hz in the scalp electroencephalogram (EEG is thought to be stronger during memory encoding for subsequently remembered items than for forgotten items. According to simultaneous EEG-functional magnetic resonance imaging (fMRI measurements, the memory-dependent EEG theta is associated with multiple regions of the brain. This suggests that the multiple regions cooperate with EEG theta synchronization during successful memory encoding. However, a question still remains: What kind of neural dynamic organizes such a memory-dependent global network? In this study, the modulation of the EEG theta entrainment property during successful encoding was hypothesized to lead to EEG theta synchronization among a distributed network. Then, a transient response of EEG theta to a theta-band photic flicker with a short duration was evaluated during memory encoding. In the results, flicker-induced EEG power increased and decreased with a time constant of several hundred milliseconds following the onset and the offset of the flicker, respectively. Importantly, the offset response of EEG power was found to be significantly decreased during successful encoding. Moreover, the offset response of the phase locking index was also found to associate with memory performance. According to computational simulations, the results are interpreted as a smaller time constant (i.e., faster response of a driven harmonic oscillator rather than a change in the spontaneous oscillatory input. This suggests that the fast response of EEG theta forms a global EEG theta network among memory-related regions during successful encoding, and it contributes to a flexible formation of the network along the time course.

  2. Novel space alters theta and gamma synchrony across the longitudinal axis of the hippocampus

    Directory of Open Access Journals (Sweden)

    stephanie c penley

    2013-06-01

    Full Text Available Hippocampal theta (6-10 Hz and gamma (25-50 Hz and 65-100 Hz local field potentials reflect the dynamic synchronization of inputs impinging upon hippocampal neurons. Novel experience is known to engage hippocampal physiology and promote successful encoding. Does novelty synchronize or desynchronize theta and/or gamma frequency inputs across the septotemporal (long axis of the hippocampus? The present study tested the hypothesis that a novel spatial environment would alter theta power and coherence across the long axis. We compared theta and gamma local field potential signals at individual (power and millimeter distant electrode pairs (coherence within the dentate gyrus (DG and CA1 region while rats navigated a runway 1 in a familiar environment, 2 with a modified path in the same environment and 3 in a novel space. Locomotion in novel space was related to increases in theta and gamma power at most CA1 and DG sites. The increase in theta and gamma power was concurrent with an increase in theta and gamma coherence across the long axis of CA1; however, there was a significant decrease in theta coherence across the long axis of the DG. These findings illustrate significant shifts in the synchrony of entorhinal, CA3 and/or neuromodulatory afferents conveying novel spatial information to the dendritic fields of CA1 and DG targets across the long axis of the hippocampus. This shift suggests that the entire theta/gamma-related input to the CA1 network, and likely output, receives and conveys a more coherent message in response to novel sensory experience. Such may contribute to the successful encoding of novel sensory experience.

  3. Hippocampal Non-Theta-Contingent Eyeblink Classical Conditioning: A Model System for Neurobiological Dysfunction.

    Science.gov (United States)

    Cicchese, Joseph J; Berry, Stephen D

    2016-01-01

    Typical information processing is thought to depend on the integrity of neurobiological oscillations that may underlie coordination and timing of cells and assemblies within and between structures. The 3-7 Hz bandwidth of hippocampal theta rhythm is associated with cognitive processes essential to learning and depends on the integrity of cholinergic, GABAergic, and glutamatergic forebrain systems. Since several significant psychiatric disorders appear to result from dysfunction of medial temporal lobe (MTL) neurochemical systems, preclinical studies on animal models may be an important step in defining and treating such syndromes. Many studies have shown that the amount of hippocampal theta in the rabbit strongly predicts the acquisition rate of classical eyeblink conditioning and that impairment of this system substantially slows the rate of learning and attainment of asymptotic performance. Our lab has developed a brain-computer interface that makes eyeblink training trials contingent upon the explicit presence or absence of hippocampal theta. The behavioral benefit of theta-contingent training has been demonstrated in both delay and trace forms of the paradigm with a two- to fourfold increase in learning speed over non-theta states. The non-theta behavioral impairment is accompanied by disruption of the amplitude and synchrony of hippocampal local field potentials, multiple-unit excitation, and single-unit response patterns dependent on theta state. Our findings indicate a significant electrophysiological and behavioral impact of the pretrial state of the hippocampus that suggests an important role for this MTL system in associative learning and a significant deleterious impact in the absence of theta. Here, we focus on the impairments in the non-theta state, integrate them into current models of psychiatric disorders, and suggest how improvement in our understanding of neurobiological oscillations is critical for theories and treatment of psychiatric

  4. [Theta/beta ratio (NEBA) in the diagnosis of attention deficit hyperactivity disorder].

    Science.gov (United States)

    Delgado-Mejía, Iván D; Palencia-Avendaño, M Luisa; Mogollón-Rincón, Carolina; Etchepareborda, Máximo C

    2014-02-24

    Introduccion. En julio del año 2013, la Food and Drug Administration estadounidense aprobo el NEBA como el primer dispositivo para la evaluacion complementaria del trastorno por deficit de atencion/hiperactividad (TDAH), basado en el electroencefalograma cuantificado (EEGq) e incluyendo la relacion theta/beta estandarizada, cuyos resultados fueron consistentes con la evaluacion clinica, tanto medica como psicologica, y es una herramienta util para determinar si el TDAH es primario, secundario o comorbido a otro trastorno. Sin embargo, ninguna de las publicaciones, hasta la fecha, especifica si se trata de un cociente theta/beta total, o theta/beta-1 y theta/beta-2, como tampoco se aportan datos para discriminar entre subtipos diagnosticos del TDAH. Objetivo. Cuantificar los cocientes theta/beta, a traves del EEGq, en una muestra de pacientes rioplatenses con diagnostico principal confirmado de TDAH, para comparar el patron neurofisiologico segun el subtipo diagnostico. Pacientes y metodos. Muestra aleatoria estratificada de 62 sujetos de ambos sexos, de 8 a 17 años, distribuidos en dos grupos segun subtipo diagnostico, TDAH subtipo deficit de atencion (n = 31) y TDAH subtipo combinado (n = 31). Resultados. Se confirman cocientes altos theta/beta-1 y theta/beta-2 en la region Cz, mayores a los cocientes en las areas C3 y C4. Se encontraron diferencias moderadas y estadisticamente significativas entre los dos subtipos solo en la banda beta-1 en las regiones occipitales. El analisis de la coherencia interhemisferica sugiere una asociacion del pico de potencia cruzada con el subtipo diagnostico, que para el subtipo combinado es el pico mas rapido (10 Hz). No se encuentran diferencias importantes al analizar los espectros de fase, ni los cocientes theta/alfa. Conclusiones. Si bien la bibliografia cientifica, especificamente el sistema NEBA, plantea la importancia del cociente theta/beta en el diagnostico diferencial del TDAH de muestras controles y otros trastornos

  5. Role of CA3 theta-modulated interneurons during the transition to spontaneous seizures.

    Science.gov (United States)

    Karunakaran, Suganya; Grasse, Dane W; Moxon, Karen A

    2016-09-01

    Multiple studies have observed heterogeneous neuronal firing patterns as a local network transitions to spontaneous seizures. We demonstrated that separately examining interneurons and pyramidal cells during this transition in a rat model of temporal lobe epilepsy elucidates some of this heterogeneity. Recently, it was demonstrated that classifying cells into specific theta-related subtypes further clarified the heterogeneity. Moreover, changes in neuronal synchrony with the local field potential were identified and determined to be specific to interneurons during the transition to seizures. To extend our understanding of the chronic changes in epileptic networks, we examined field potentials and single neuron activity in the CA3 hippocampus of pilocarpine-treated rats during interictal periods and compared these to neuronal activity in healthy controls and during preictal periods. Neurons were classified into theta-subtypes based on changes in firing patterns during theta periods. As previously reported, we find a high probability of theta oscillations before seizure onset and a selective increase in theta-on interneuron firing rate immediately preceding seizure onset. However, we also find overall slower theta rhythm and a general decrease in subtype-specific firing during interictal periods compared to that in control animals. The decrease in subtype specific interneuron activity is accompanied by increases in synchrony. Exceptionally, theta-on interneurons, that selectively increase their firing rate at seizure onset, maintain similar firing rates and synchrony as controls during interictal period. These data suggest that increased synchrony during interictal periods may compensate for low firing rates creating instability during theta that is prone to seizure initiation via a transition to hyper-synchronous activation of theta-on interneurons.

  6. Timelike gamma* N -> Delta form factors and Delta Dalitz decay

    CERN Document Server

    Ramalho, G

    2012-01-01

    We extend a covariant model, tested before in the spacelike region for the physical and lattice QCD regimes, to a calculation of the gamma* N -> Delta reaction in the timelike region, where the square of the transfered momentum, q^2, is positive (q^2>0). We estimate the Dalitz decay Delta -> Ne+e- and the Delta distribution mass distribution function. The results presented here can be used to simulate the NN -> NNe+e- reactions at moderate beam kinetic energies.

  7. [Extraction and properties of microcapsulated alpha-chymotrypsin].

    Science.gov (United States)

    Aĭsina, R B; Kazanskaia, N F; Lukasheva, E V; Berezin, I V

    1976-09-01

    A method of microencapsulating of the proteolytic enzyme alpha-chymotrypsin into semi-permeable nylon membranes is worked out. The membrane is a polimer of 1,6-hexamethylenediamine and sebacoyl chloride. alpha-Chymotrypsin is enclosed into the capsule together with polyethyleneimine, capable of joining the walls of microcapsules and making the membrane more stable. The optimal concentrations of polyenthyleneimine and alpha-chymotrypsin are 5% and 1% correspondingly. The highest yield of microencapsulated enzyme was obtained for completely acetylated delta-chymotrypsin. The kinetic properties of microencapsulated alpha-chymotrypsin change very slightly as compared to those of the native one.

  8. Theta-rhythmic drive between medial septum and hippocampus in slow-wave sleep and microarousal: a Granger causality analysis

    Science.gov (United States)

    Kang, D.; Ding, M.; Topchiy, I.; Shifflett, L.

    2015-01-01

    Medial septum (MS) plays a critical role in controlling the electrical activity of the hippocampus (HIPP). In particular, theta-rhythmic burst firing of MS neurons is thought to drive lasting HIPP theta oscillations in rats during waking motor activity and REM sleep. Less is known about MS-HIPP interactions in nontheta states such as non-REM sleep, in which HIPP theta oscillations are absent but theta-rhythmic burst firing in subsets of MS neurons is preserved. The present study used Granger causality (GC) to examine the interaction patterns between MS and HIPP in slow-wave sleep (SWS, a nontheta state) and during its short interruptions called microarousals (a transient theta state). We found that during SWS, while GC revealed a unidirectional MS→HIPP influence over a wide frequency band (2–12 Hz, maximum: ∼8 Hz), there was no theta peak in the hippocampal power spectra, indicating a lack of theta activity in HIPP. In contrast, during microarousals, theta peaks were seen in both MS and HIPP power spectra and were accompanied by bidirectional GC with MS→HIPP and HIPP→MS theta drives being of equal magnitude. Thus GC in a nontheta state (SWS) vs. a theta state (microarousal) primarily differed in the level of HIPP→MS. The present findings suggest a modification of our understanding of the role of MS as the theta generator in two regards. First, a MS→HIPP theta drive does not necessarily induce theta field oscillations in the hippocampus, as found in SWS. Second, HIPP theta oscillations entail bidirectional theta-rhythmic interactions between MS and HIPP. PMID:26354315

  9. Fluctuating Inhibitory Inputs Promote Reliable Spiking at Theta Frequencies in Hippocampal Interneurons

    OpenAIRE

    Sritharan, Duluxan; Frances K Skinner

    2012-01-01

    Theta-frequency (4–12 Hz) rhythms in the hippocampus play important roles in learning and memory. CA1 interneurons located at the stratum lacunosum-moleculare and radiatum junction (LM/RAD) are thought to contribute to hippocampal theta population activities by rhythmically pacing pyramidal cells with inhibitory postsynaptic potentials. This implies that LM/RAD cells need to fire reliably at theta frequencies in vivo. To determine whether this could occur, we use biophysically based LM/RAD mo...

  10. Generation of non-zero $\\theta_{13}$ in broken $A_4$ neutrino mass model

    CERN Document Server

    Borah, Manikanta; Das, Mrinal Kumar

    2014-01-01

    Stability of neutrino masses and mixings with non-zero $\\theta_{13}$ is an important issue in recent neutrino physics. In context of this, a detail analysis on two-fold degenerate $(m_1=m_2, m_3)$ neutrino mass model is done with Renormaization Group Equation (RGE) in Minimal Supersymmetric Standard Model (MSSM). Considering the input values of neutrino masses and mixing angles at high scale predictions are studied at low energy scale using RGE. We have also found that two-fold degenerate model with $\\theta_{13}=0$ can produce consistent results at low energy with non-zero $\\theta_{13}$ from the breaking of a generic $A_4$ model.

  11. Octant of $\\theta_{23}$ in danger with a light sterile neutrino

    CERN Document Server

    Agarwalla, Sanjib Kumar; Palazzo, Antonio

    2016-01-01

    Present global fits of world neutrino data hint towards non-maximal $\\theta_{23}$ with two nearly degenerate solutions, one in the lower octant ($\\theta_{23} \\pi/4$). This octant ambiguity of $\\theta_{23}$ is one of the fundamental issues in the neutrino sector, and its resolution is a crucial goal of next-generation long-baseline (LBL) experiments. In this letter, we address for the first time, the impact of a light eV-scale sterile neutrino towards such a measurement, taking the Deep Underground Neutrino Experiment (DUNE) as a case study. In the so-called 3+1 scheme involving three active and one sterile neutrino, the $\

  12. Double Chooz: optimizing the sensitivity to {theta}{sub 13} with a multi-detector setup

    Energy Technology Data Exchange (ETDEWEB)

    Novella, P. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain)

    2012-08-15

    The best upper limit to the neutrino mixing angle {theta}{sub 13} is set by the CHOOZ experiment. The eventual measurement of {theta}{sub 13} in reactor neutrino experiments relies on a reduction of the CHOOZ systematics of about 1 order of magnitude, along with a major increase of the luminosity. Provided that enough statistics are achieved, fighting the systematics becomes the key towards {theta}{sub 13}. The Double Chooz experiment engages this fight with a multi-detector set up.

  13. Some theorems on the explicit evaluation of Ramanujan's theta-functions

    Directory of Open Access Journals (Sweden)

    Nayandeep Deka Baruah

    2004-01-01

    Full Text Available Bruce C. Berndt et al. and Soon-Yi Kang have proved many of Ramanujan's formulas for the explicit evaluation of the Rogers-Ramanujan continued fraction and theta-functions in terms of Weber-Ramanujan class invariants. In this note, we give alternative proofs of some of these identities of theta-functions recorded by Ramanujan in his notebooks and deduce some formulas for the explicit evaluation of his theta-functions in terms of Weber-Ramanujan class invariants.

  14. Developmental differences in beta and theta power during sentence processing

    Directory of Open Access Journals (Sweden)

    Julie M. Schneider

    2016-06-01

    Full Text Available Although very young children process ongoing language quickly and effortlessly, research indicates that they continue to improve and mature in their language skills through adolescence. This prolonged development may be related to differing engagement of semantic and syntactic processes. This study used event related potentials and time frequency analysis of EEG to identify developmental differences in neural engagement as children (ages 10–12 and adults performed an auditory verb agreement grammaticality judgment task. Adults and children revealed very few differences in comprehending grammatically correct sentences. When identifying grammatical errors, however, adults displayed widely distributed beta and theta power decreases that were significantly less pronounced in children. Adults also demonstrated a significant P600 effect, while children exhibited an apparent N400 effect. Thus, when identifying subtle grammatical errors in real time, adults display greater neural activation that is traditionally associated with syntactic processing whereas children exhibit greater activity more commonly associated with semantic processing. These findings support previous claims that the cognitive and neural underpinnings of syntactic processing are still developing in adolescence, and add to them by more clearly identifying developmental changes in the neural oscillations underlying grammatical processing.

  15. Dissipation and {theta} {sub 13} in neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, R.L.N.; Guzzo, M.M. [Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin, Campinas, Sao Paulo (Brazil)

    2013-05-15

    We obtain a complete survival and transition probability involving three neutrino flavors when dissipation effects in vacuum are taken into consideration. In an approach that presents decoherence and relaxation effects, we study the behavior of the probabilities obtained from complete positivity constraints. Making the von Neumann entropy increase in time, many cases can be obtained and studied with the Lindblad master equation with addition of only one or two parameters related to dissipation. New possibilities are obtained when we take into account two decoherence parameters with different magnitudes which are given by reactor and accelerator neutrino oscillation experiments. We also present a model with only one parameter that has an important symmetry property, which can be used when the effective matter potential is important. Furthermore, the dissipation effects can contribute to the appearance of neutrinos that can hide or imitate the {theta} {sub 13} effects and we study these possibilities showing that dissipative effects have an important role in three-neutrino oscillations. (orig.)

  16. GEOMETRIC CALIBRATION OF FULL SPHERICAL PANORAMIC RICOH-THETA CAMERA

    Directory of Open Access Journals (Sweden)

    S. Aghayari

    2017-05-01

    Full Text Available A novel calibration process of RICOH-THETA, full-view fisheye camera, is proposed which has numerous applications as a low cost sensor in different disciplines such as photogrammetry, robotic and machine vision and so on. Ricoh Company developed this camera in 2014 that consists of two lenses and is able to capture the whole surrounding environment in one shot. In this research, each lens is calibrated separately and interior/relative orientation parameters (IOPs and ROPs of the camera are determined on the basis of designed calibration network on the central and side images captured by the aforementioned lenses. Accordingly, designed calibration network is considered as a free distortion grid and applied to the measured control points in the image space as correction terms by means of bilinear interpolation. By performing corresponding corrections, image coordinates are transformed to the unit sphere as an intermediate space between object space and image space in the form of spherical coordinates. Afterwards, IOPs and EOPs of each lens are determined separately through statistical bundle adjustment procedure based on collinearity condition equations. Subsequently, ROPs of two lenses is computed from both EOPs. Our experiments show that by applying 3*3 free distortion grid, image measurements residuals diminish from 1.5 to 0.25 degrees on aforementioned unit sphere.

  17. Continuous theta-burst stimulation modulates tactile synchronization

    Science.gov (United States)

    2013-01-01

    Background Temporal order judgement (TOJ) is the ability to detect the order of occurrence of two sequentially delivered stimuli. Previous research has shown that TOJ in the presence of synchronized periodic conditioning stimuli impairs TOJ performance, and this phenomenon is suggested to be mediated by GABAergic interneurons that cause perceptual binding across the two skin sites. Application of continuous theta-burst repetitive TMS (cTBS) over primary somatosensory cortex (SI) alters temporal and spatial tactile perception. The purpose of this study was to examine TOJ perception in the presence and absence of synchronized periodic conditioning stimuli before and after cTBS applied over left-hemisphere SI. A TOJ task was administered on the right index and middle finger (D2 and D3) in two separate sessions in the presence and absence of conditioning stimuli (a background low amplitude sinusoidal vibration). Results CTBS reduced the impact of the conditioning stimuli on TOJ performance for up to 18 minutes following stimulation while sham cTBS did not affect TOJ performance. In contrast, the TOJ task performed in the absence of synchronized conditioning stimulation was unaltered following cTBS. Conclusion We conclude that cTBS suppresses inhibitory networks in SI that mediate perceptual binding during TOJ synchronization. CTBS offers one method to suppress cortical excitability in the cortex and potentially benefit clinical populations with altered inhibitory cortical circuits. Additionally, TOJ measures with conditioning stimuli may provide an avenue to assess sensory processing in neurologically impaired patient populations. PMID:23968301

  18. Hardy-Petrovitch-Hutchinson's problem and partial theta function

    CERN Document Server

    Kostov, Vladimir Petrov

    2011-01-01

    In 1907 M.Petrovitch initiated the study of a class of entire functions all whose finite sections are real-rooted polynomials. An explicit description of this class in terms of the coefficients of a series is impossible since it is determined by an infinite number of discriminantal inequalities one for each degree. However, interesting necessary or sufficient conditions can be formulated. In particular, J.I.Hutchinson has shown that an entire function p(x)=a_0+a_1x+...+a_nx^n+... with strictly positive coefficients has the property that any its finite segment a_ix^i+...+a_jx^j has all real roots if and only if for all i=1,2,... one has a_i^2/a_{i-1}a_{i+1} is greater than or equal to 4. In the present paper we give sharp lower bounds on the ratios a_i^2/a_{i-1}a_{i+1} for the class considered by M.Petrovitch. In particular, we show that the limit of these minima when i tends to infinity equals the inverse of the maximal positive value of the parameter for which the classical partial theta function belongs to ...

  19. Non-Standard Models, Solar Neutrinos, and Large \\theta_{13}

    CERN Document Server

    Bonventre, R; Klein, J R; Gann, G D Orebi; Seibert, S; Wasalski, O

    2013-01-01

    Solar neutrino experiments have yet to see directly the transition region between matter-enhanced and vacuum oscillations. The transition region is particularly sensitive to models of non-standard neutrino interactions and propagation. We examine several such non-standard models, which predict a lower-energy transition region and a flatter survival probability for the ^{8}B solar neutrinos than the standard large-mixing angle (LMA) model. We find that while some of the non-standard models provide a better fit to the solar neutrino data set, the large measured value of \\theta_{13} and the size of the experimental uncertainties lead to a low statistical significance for these fits. We have also examined whether simple changes to the solar density profile can lead to a flatter ^{8}B survival probability than the LMA prediction, but find that this is not the case for reasonable changes. We conclude that the data in this critical region is still too poor to determine whether any of these models, or LMA, is the bes...

  20. Geometric Calibration of Full Spherical Panoramic Ricoh-Theta Camera

    Science.gov (United States)

    Aghayari, S.; Saadatseresht, M.; Omidalizarandi, M.; Neumann, I.

    2017-05-01

    A novel calibration process of RICOH-THETA, full-view fisheye camera, is proposed which has numerous applications as a low cost sensor in different disciplines such as photogrammetry, robotic and machine vision and so on. Ricoh Company developed this camera in 2014 that consists of two lenses and is able to capture the whole surrounding environment in one shot. In this research, each lens is calibrated separately and interior/relative orientation parameters (IOPs and ROPs) of the camera are determined on the basis of designed calibration network on the central and side images captured by the aforementioned lenses. Accordingly, designed calibration network is considered as a free distortion grid and applied to the measured control points in the image space as correction terms by means of bilinear interpolation. By performing corresponding corrections, image coordinates are transformed to the unit sphere as an intermediate space between object space and image space in the form of spherical coordinates. Afterwards, IOPs and EOPs of each lens are determined separately through statistical bundle adjustment procedure based on collinearity condition equations. Subsequently, ROPs of two lenses is computed from both EOPs. Our experiments show that by applying 3*3 free distortion grid, image measurements residuals diminish from 1.5 to 0.25 degrees on aforementioned unit sphere.

  1. High-resolution X-ray spectroscopy of Theta Car

    CERN Document Server

    Naze, Yael

    2008-01-01

    Context : The peculiar hot star Theta Car in the open cluster IC2602 is a blue straggler as well as a single-line binary of short period (2.2d). Aims : Its high-energy properties are not well known, though X-rays can provide useful constraints on the energetic processes at work in binaries as well as in peculiar, single objects. Methods : We present the analysis of a 50ks exposure taken with the XMM-Newton observatory. It provides medium as well as high-resolution spectroscopy. Results : Our high-resolution spectroscopy analysis reveals a very soft spectrum with multiple temperature components (1--6MK) and an X-ray flux slightly below the `canonical' value (log[L_X(0.1-10.)/L_{BOL}] ~ -7). The X-ray lines appear surprisingly narrow and unshifted, reminiscent of those of beta Cru and tau Sco. Their relative intensities confirm the anomalous abundances detected in the optical domain (C strongly depleted, N strongly enriched, O slightly depleted). In addition, the X-ray data favor a slight depletion in neon and ...

  2. Revisiting Discrete Dark Matter Model:\\theta_{13}\

    CERN Document Server

    Hamada, Yuta; Ogasahara, Atsushi; Omura, Yuji; Takayama, Fumihiro; Yasuhara, Daiki

    2014-01-01

    We revisit the discrete dark matter model with $A_4$ flavor symmetry originally introduced by M.Hirsch {\\it et.al}. We show that radiative corrections can lead to non-zero $\\theta_{13}$ and non-zero mass for the lightest neutrino. We find an interesting relation among neutrino mixing parameters and it indicates the sizable deviation of $s_{23}$ from the maximal angle $s_{23}^2=1/2$ and the degenerate mass spectrum for neutrinos. Also we study the possibilities that the right-handed neutrino is a dark matter candidate. Assuming the thermal freeze-out explains observed dark matter abundance, TeV-scale right-handed neutrino and flavored scalar bosons are required. In such a case, flavor symmetry plays an important role for the suppression of lepton flavor violating processes as well as for the stability of dark matter. We show that this scenario can be viable against currently existing constraints from collider, low energy experiments and cosmological observations.

  3. Discrete Flavour Groups, \\theta_13 and Lepton Flavour Violation

    CERN Document Server

    Altarelli, Guido; Merlo, Luca; Stamou, Emmanuel

    2012-01-01

    Discrete flavour groups have been studied in connection with special patterns of neutrino mixing suggested by the data, such as Tri-Bimaximal mixing (groups A4, S4...) or Bi-Maximal mixing (group S4...) etc. We review the predictions for sin(\\theta_13) in a number of these models and confront them with the experimental measurements. We compare the performances of the different classes of models in this respect. We then consider, in a supersymmetric framework, the important implications of these flavour symmetries on lepton flavour violating processes, like \\mu -> e gamma and similar processes. We discuss how the existing limits constrain these models, once their parameters are adjusted so as to optimize the agreement with the measured values of the mixing angles. In the simplified CMSSM context, adopted here just for indicative purposes, the small tan(beta) range and heavy SUSY mass scales are favoured by lepton flavour violating processes, which makes it even more difficult to reproduce the reported muon g-2...

  4. Bilateral theta-burst TMS to influence global gestalt perception.

    Science.gov (United States)

    Ritzinger, Bernd; Huberle, Elisabeth; Karnath, Hans-Otto

    2012-01-01

    While early and higher visual areas along the ventral visual pathway in the inferotemporal cortex are critical for the recognition of individual objects, the neural representation of human perception of complex global visual scenes remains under debate. Stroke patients with a selective deficit in the perception of a complex global Gestalt with intact recognition of individual objects - a deficit termed simultanagnosia - greatly helped to study this question. Interestingly, simultanagnosia typically results from bilateral lesions of the temporo-parietal junction (TPJ). The present study aimed to verify the relevance of this area for human global Gestalt perception. We applied continuous theta-burst TMS either unilaterally (left or right) or bilateral simultaneously over TPJ. Healthy subjects were presented with hierarchically organized visual stimuli that allowed parametrical degrading of the object at the global level. Identification of the global Gestalt was significantly modulated only for the bilateral TPJ stimulation condition. Our results strengthen the view that global Gestalt perception in the human brain involves TPJ and is co-dependent on both hemispheres.

  5. Bilateral theta-burst TMS to influence global gestalt perception.

    Directory of Open Access Journals (Sweden)

    Bernd Ritzinger

    Full Text Available While early and higher visual areas along the ventral visual pathway in the inferotemporal cortex are critical for the recognition of individual objects, the neural representation of human perception of complex global visual scenes remains under debate. Stroke patients with a selective deficit in the perception of a complex global Gestalt with intact recognition of individual objects - a deficit termed simultanagnosia - greatly helped to study this question. Interestingly, simultanagnosia typically results from bilateral lesions of the temporo-parietal junction (TPJ. The present study aimed to verify the relevance of this area for human global Gestalt perception. We applied continuous theta-burst TMS either unilaterally (left or right or bilateral simultaneously over TPJ. Healthy subjects were presented with hierarchically organized visual stimuli that allowed parametrical degrading of the object at the global level. Identification of the global Gestalt was significantly modulated only for the bilateral TPJ stimulation condition. Our results strengthen the view that global Gestalt perception in the human brain involves TPJ and is co-dependent on both hemispheres.

  6. Modulation of EEG Theta Band Signal Complexity by Music Therapy

    Science.gov (United States)

    Bhattacharya, Joydeep; Lee, Eun-Jeong

    The primary goal of this study was to investigate the impact of monochord (MC) sounds, a type of archaic sounds used in music therapy, on the neural complexity of EEG signals obtained from patients undergoing chemotherapy. The secondary goal was to compare the EEG signal complexity values for monochords with those for progressive muscle relaxation (PMR), an alternative therapy for relaxation. Forty cancer patients were randomly allocated to one of the two relaxation groups, MC and PMR, over a period of six months; continuous EEG signals were recorded during the first and last sessions. EEG signals were analyzed by applying signal mode complexity, a measure of complexity of neuronal oscillations. Across sessions, both groups showed a modulation of complexity of beta-2 band (20-29Hz) at midfrontal regions, but only MC group showed a modulation of complexity of theta band (3.5-7.5Hz) at posterior regions. Therefore, the neuronal complexity patterns showed different changes in EEG frequency band specific complexity resulting in two different types of interventions. Moreover, the different neural responses to listening to monochords and PMR were observed after regular relaxation interventions over a short time span.

  7. Production and Width of the Pentaquark Theta+(1540) in Strangeness Production in the Proton-Proton System

    CERN Document Server

    Dillig, M

    2006-01-01

    We analyze recent experimental information on the excitation of the Theta+(1540) pentaquark in the hadronic reaction pp -> p Sigma+ K0. Upon describing the conventional production process - which serves as a normalization - in a meson exchange model, we estimate the resonant Theta+ induced cross section and the width of the pentaquark via K - exchange in a meson-baryon and a quark-gluon model. From a comparison with experiment we extract information on the width of the Theta+, the p Theta+ K0 coupling constant in the meson exchange and the relative s or p wave function for a nucleon-kaon cluster in the Theta+.

  8. Measurement of the product branching fraction $B(c \\to \\Theta_{c}X) \\cdot B(\\Theta_{c} \\to \\LambdaX)$

    CERN Document Server

    Ammar, R; Bean, A; Besson, D; Brabant, P; Bull, H; Davis, R; Holliday, J; Kotov, S A; Kravchenko, I V; Kwak, N; Robertson, I; Stutz, R P; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Mahmood, A H; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Kagan, H; Kass, R; Lorenc, J; Schwarthoff, H; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A; Bishai, M; Chen, S; Fast, J; Hinson, J W; Lee, J; Menon, N; Miller, D H; Shibata, E I; Shipsey, I P J; Kwon, Y; Lyon, A L; Thorndike, E H; Jessop, C P; Lingel, K; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Korolkov, I Ya; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Dambasuren, E; Kopp, S E; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Titov, A; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Csorna, S E; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Pomianowski, P A; Schrenk, S; Bonvicini, G; Cinabro, D; Greene, R; Perera, L P; Zhou, G J; Chan, S; Eigen, G; Lipeles, E; Schmidtler, M; Shapiro, A; Sun, W M; Urheim, J; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Gronberg, J B; Hill, T S; Lange, D J; Morrison, R J; Nelson, T K; Richman, J D; Briere, R A; Behrens, B H; Ford, W T; Gritsan, A; Krieg, H; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lee, T; Liu, Y; Meyer, T O; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Valant-Spaight, B L; Warburton, A; Avery, P; Lohner, M; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J; Brandenburg, G; Ershov, A; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J

    2000-01-01

    Based on an a high statistics e+e- -> ccbar data sample, we report on the inclusive rate for charmed baryons to decay into / particles using charm-event tagging. We select e+e- -> ccbar events which have a clear anti-charm tag and measure the / content in the hemisphere opposite the tag (charge conjugate modes are implicit). This allows us to determine the product branching fraction: B(/)=B(c->Theta_c)*B(Theta_c->/\\X), where Theta_c represents a sum over all charmed baryons produced in e+e- fragmentation at sqrt(s)=10.5 GeV, given our specific tags. We obtain B(/)=(1.87+/-0.03+/-0.33)%

  9. Relationship between regional hemodynamic activity and simultaneously recorded EEG-theta associated with mental arithmetic-induced workload.

    Science.gov (United States)

    Sammer, Gebhard; Blecker, Carlo; Gebhardt, Helge; Bischoff, Matthias; Stark, Rudolf; Morgen, Katrin; Vaitl, Dieter

    2007-08-01

    Theta increases with workload and is associated with numerous processes including working memory, problem solving, encoding, or self monitoring. These processes, in turn, involve numerous structures of the brain. However, the relationship between regional brain activity and the occurrence of theta remains unclear. In the present study, simultaneous EEG-fMRI recordings were used to investigate the functional topography of theta. EEG-theta was enhanced by mental arithmetic-induced workload. For the EEG-constrained fMRI analysis, theta-reference time-series were extracted from the EEG, reflecting the strength of theta occurrence during the time course of the experiment. Theta occurrence was mainly associated with activation of the insular cortex, hippocampus, superior temporal areas, cingulate cortex, superior parietal, and frontal areas. Though observation of temporal and insular activation is in accord with the theory that theta specifically reflects encoding processes, the involvement of several other brain regions implies that surface-recorded theta represents comprehensive functional brain states rather than specific processes in the brain. The results provide further evidence for the concept that emergent theta band oscillations represent dynamic functional binding of widely distributed cortical assemblies, essential for cognitive processing. This binding process may form the source of surface-recorded EEG theta. 2006 Wiley-Liss, Inc.

  10. Delta II commercial space transportation

    Science.gov (United States)

    Meyers, J. F.

    1988-07-01

    Delta II is an upgraded variant of the Delta family of launch vehicles that has been in use by NASA since 1960. Among the design improvements incorporated by Delta II is a cryogenic-propellant second stage, a 2.89-m diameter satellite-protecting nose fairing, graphite/epoxy solid rocket motor cases, and 12:1 main engine expansion nozzle. The manufacturer/operator offers Delta II customers a dedicated, single satellite launch capability fully tailored to the given spacecraft's unique mission requirements.

  11. Effects of nicotine stimulation on spikes, theta frequency oscillations, and spike-theta oscillation relationship in rat medial septum diagonal band Broca slices

    Institute of Scientific and Technical Information of China (English)

    Dong WEN; Ce PENG; Gao-xiang OU-YANG; Zainab HENDERSON; Xiao-li LI; Cheng-biao LU

    2013-01-01

    Aim:Spiking activities and neuronal network oscillations in the theta frequency range have been found in many cortical areas during information processing.The aim of this study is to determine whether nicotinic acetylcholine receptors (nAChRs) mediate neuronal network activity in rat medial septum diagonal band Broca (MSDB) slices.Methods:Extracellular field potentials were recorded in the slices using an Axoprobe 1A amplifier.Data analysis was performed offline.Spike sorting and local field potential (LFP) analyses were performed using Spike2 software.The role of spiking activity in the generation of LFP oscillations in the slices was determined by analyzing the phase-time relationship between the spikes and LFP oscillations.Circular statistic analysis based on the Rayleigh test was used to determine the significance of phase relationships between the spikes and LFP oscillations.The timing relationship was examined by quantifying the spike-field coherence (SFC).Results:Application of nicotine (250 nmol/L) induced prominent LFP oscillations in the theta frequency band and both small-and large-amplitude population spiking activity in the slices.These spikes were phase-locked to theta oscillations at specific phases.The Rayleigh test showed a statistically significant relationship in phase-locking between the spikes and theta oscillations.Larger changes in the SFC were observed for large-amplitude spikes,indicating an accurate timing relationship between this type of spike and LFP oscillations.The nicotine-induced spiking activity (large-amplitude population spikes) was suppressed by the nAChR antagonist dihydro-β-erythroidine (0.3 μmol/L).Conclusion:The results demonstrate that large-amplitude spikes are phase-locked to theta oscillations and have a high spike-timing accuracy,which are likely a main contributor to the theta oscillations generated in MSDB during nicotine receptor activation.

  12. TAO/TRITON, RAMA, and PIRATA Buoys, 5-Day, Sigma-Theta

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has 5-day Sigma-Theta (Potential Density Anomaly) data from the TAO/TRITON (Pacific Ocean, http://www.pmel.noaa.gov/tao/), RAMA (Indian Ocean,...

  13. How to implant a causal $\\Theta$ function into the tachyon field operator

    CERN Document Server

    Perepelitsa, Vassili

    2015-01-01

    A Lorentz-covariant introduction of a causal $\\Theta$ function into the tachyon quantum field operator is suggested. Some features of a Lorentz-violating (but Lorentz-covariant) tachyon Lagrangian are considered.

  14. Study of theta-Vacua in the 2-d O(3) Model

    CERN Document Server

    Bögli, Michael; Pepe, Michele; Wiese, Uwe-Jens

    2012-01-01

    We investigate the continuum limit of the step scaling function in the 2-d O(3) model with different theta-vacua. Since we find a different continuum value of the step scaling function for each value of theta, we can conclude that theta indeed is a relevant parameter of the theory and does not get renormalized non-perturbatively. Furthermore, we confirm the result of the conjectured exact S-matrix theory, which predicts the continuum value at theta = pi. To obtain high precision data, we use a modified Hasenbusch improved estimator and an action with an optimized constraint, which has very small cut-off effects. The optimized constraint action combines the standard action of the 2-d O(3) model with a topological action. The topological action constrains the angle between neighboring spins and is therefore invariant against small deformations of the field.

  15. $r$-Tuple Error Functions and Indefinite Theta Series of Higher-Depth

    CERN Document Server

    Nazaroglu, Caner

    2016-01-01

    Theta functions for definite signature lattices constitute a rich source of modular forms. A natural question is then their generalization to indefinite signature lattices. One way to ensure a convergent theta series while keeping the holomorphicity property of definite signature theta series is to restrict the sum over lattice points to a proper subset. Although such series do not have the modular properties that a definite signature theta function has, as shown by Zwegers for signature $(1,n-1)$ lattices, they can be completed to a function that has these modular properties by compromising on the holomorphicity property in a certain way. This construction has recently been generalized to signature $(2,n-2)$ lattices by Alexandrov, Banerjee, Manschot, and Pioline. A crucial ingredient in this work is the notion of double error functions which naturally lends itself to generalizations to higher dimensions. In this work we study the properties of such higher dimensional error functions which we will call $r$-t...

  16. Optical design of f-theta lens for dual wavelength selective laser melting

    Science.gov (United States)

    Feng, Lianhua; Cao, Hongzhong; Zhang, Ning; Xu, Xiping; Duan, Xuanming

    2016-10-01

    F-theta lens is an important unit for selective laser melting (SLM) manufacture. The dual wavelength f-theta lens has not been used in SLM manufacture. Here, we present the design of the f-theta lens which satisfies SLM manufacture with coaxial 532 nm and 1030 nm 1080 nm laser beams. It is composed of three pieces of spherical lenses. The focal spots for 532 nm laser and 1030 nm 1080 nm laser are smaller than 35 μm and 70 μm, respectively. The results meet the demands of high precision SLM. The chromatic aberration could cause separation between two laser focal spots in the scanning plane, so chromatic aberration correction is very important to our design. The lateral color of the designed f-theta lens is less than 11 μm within the scan area of 150 mm x 150 mm, which meet the application requirements of dual wavelength selective laser melting.

  17. The consequences of large \\theta_13 for the turbulence signatures in supernova neutrinos

    CERN Document Server

    Kneller, James P

    2013-01-01

    The set of transition probabilities for a single neutrino emitted from a point source after passage through a turbulent supernova density profile have been found to be random variates drawn from parent distributions whose properties depend upon the stage of the explosion, the neutrino energy and mixing parameters, the observed channel, and the properties of the turbulence such as the amplitude C*. In this paper we examine the consequences of the recently measured mixing angle \\theta_13 upon the neutrino flavor transformation in supernova when passing through turbulence. We find the measurements of a relatively large value of \\theta_13 means the neutrinos are relatively immune to small, C* 10% the turbulence effects in the high (H) density resonance mixing channels are independent of \\theta_13 but non-resonant mixing channels are more sensitive to turbulence when \\theta_13 is large.

  18. Status of the iota (1440) and theta (1640) as gluonium candidates

    Energy Technology Data Exchange (ETDEWEB)

    Lockman, W.S.

    1983-04-01

    A review of the experimental evidence for the iota (1440) and theta (1640) states is presented. The measured properties of these states are compared with various theoretical predictions. A likely interpretation is that these states contain a large gluonic admixture.

  19. Independent Measurement of Theta13 via Neutron Capture on Hydrogen at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Butorov, I; Cao, G F; Cao, J; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chasman, C; Chen, H; Chen, Q Y; Chen, S M; Chen, X; Chen, Y X; Chen, Y; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, Y Y; Diwan, M V; Draeger, E; Du, X F; Dwyer, D A; Edwards, W R; Ely, S R; Fu, J Y; Ge, L Q; Gill, R; Gonchar, M; Gong, G H; Gong, H; Gornushkin, Y A; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Han, G H; Hans, S; He, M; Heeger, K M; Heng, Y K; Hinrichs, P; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E; Huang, H; Huang, X T; Huber, P; Hussain, G; Isvan, Z; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiang, H J; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, W C; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, A; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Liu, Y B; Lu, C; Lu, H Q; Luk, K -B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Nemchenok, I; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Y,; Tam, H; Tang, X; Themann, H; Tsang, K V; Tsang, R H M; Tull, C E; Tung, Y C; Viren, B; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webber, D M; Wei, H Y; Wei, Y D; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C C; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, G Y; Yu, J Y; Yu, Z Y; Zang, S L; Zeng, B; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, Q; Zhang, S H; Zhang, Y C; Zhang, Y M; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2014-01-01

    A new measurement of the $\\theta_{13}$ mixing angle has been obtained at the Daya Bay Reactor Neutrino Experiment via the detection of inverse beta decays tagged by neutron capture on hydrogen. The antineutrino events for hydrogen capture are distinct from those for gadolinium capture with largely different systematic uncertainties, allowing a determination independent of the gadolinium-capture result and an improvement on the precision of $\\theta_{13}$ measurement. With a 217-day antineutrino data set obtained with six antineutrino detectors and from six 2.9 GW$_{th}$ reactors, the rate deficit observed at the far hall is interpreted as $\\sin^22\\theta_{13}=0.083\\pm0.018$ in the three-flavor oscillation model. When combined with the gadolinium-capture result from Daya Bay, we obtain $\\sin^22\\theta_{13}=0.089\\pm0.008$ as the final result for the six-antineutrino-detector configuration of the Daya Bay experiment.

  20. TAO/TRITON, RAMA, and PIRATA Buoys, Daily, Sigma-Theta

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has daily Sigma-Theta (Potential Density Anomaly) data from the TAO/TRITON (Pacific Ocean, http://www.pmel.noaa.gov/tao/), RAMA (Indian Ocean,...

  1. TAO/TRITON, RAMA, and PIRATA Buoys, Quarterly, Sigma-Theta

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has quarterly Sigma-Theta (Potential Density Anomaly) data from the TAO/TRITON (Pacific Ocean, http://www.pmel.noaa.gov/tao/), RAMA (Indian Ocean,...

  2. TAO/TRITON, RAMA, and PIRATA Buoys, Monthly, Sigma-Theta

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has monthly Sigma-Theta (Potential Density Anomaly) data from the TAO/TRITON (Pacific Ocean, http://www.pmel.noaa.gov/tao/), RAMA (Indian Ocean,...

  3. Validation Study of CODES Dragonfly Network Model with Theta Cray XC System

    Energy Technology Data Exchange (ETDEWEB)

    Mubarak, Misbah [Argonne National Lab. (ANL), Argonne, IL (United States); Ross, Robert B. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-05-31

    This technical report describes the experiments performed to validate the MPI performance measurements reported by the CODES dragonfly network simulation with the Theta Cray XC system at the Argonne Leadership Computing Facility (ALCF).

  4. Phenotypic expressions of CCR5-Delta 32/Delta 32 homozygosity

    NARCIS (Netherlands)

    Nguyen, GT; Carrington, M; Beeler, JA; Dean, M; Aledort, LM; Blatt, PM; Cohen, AR; DiMichele, D; Eyster, ME; Kessler, CM; Konkle, B; Leissinger, C; Luban, N; O'Brien, SJ; Goedert, JJ; O'Brien, TR

    1999-01-01

    Objective: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-Delta 32/Delta 32 homozygous genotype has phenotypic expressions other than those related to HIV-1. Design: Study subjects were white homosexual men or men with hemophilia

  5. Phenotypic expressions of CCR5-Delta 32/Delta 32 homozygosity

    NARCIS (Netherlands)

    Nguyen, GT; Carrington, M; Beeler, JA; Dean, M; Aledort, LM; Blatt, PM; Cohen, AR; DiMichele, D; Eyster, ME; Kessler, CM; Konkle, B; Leissinger, C; Luban, N; O'Brien, SJ; Goedert, JJ; O'Brien, TR

    1999-01-01

    Objective: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-Delta 32/Delta 32 homozygous genotype has phenotypic expressions other than those related to HIV-1. Design: Study subjects were white homosexual men or men with hemophilia wh

  6. Peat compaction in deltas : implications for Holocene delta evolution

    NARCIS (Netherlands)

    van Asselen, S.|info:eu-repo/dai/nl/304838101

    2010-01-01

    Many deltas contain substantial amounts of peat, which is the most compressible soil type. Therefore, peat compaction potentially leads to high amounts of subsidence in deltas. The main objective of this research was to quantify subsidence due to peat compaction in Holocene fluvial-deltaic settings

  7. Phenotypic expressions of CCR5-Delta 32/Delta 32 homozygosity

    NARCIS (Netherlands)

    Nguyen, GT; Carrington, M; Beeler, JA; Dean, M; Aledort, LM; Blatt, PM; Cohen, AR; DiMichele, D; Eyster, ME; Kessler, CM; Konkle, B; Leissinger, C; Luban, N; O'Brien, SJ; Goedert, JJ; O'Brien, TR

    1999-01-01

    Objective: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-Delta 32/Delta 32 homozygous genotype has phenotypic expressions other than those related to HIV-1. Design: Study subjects were white homosexual men or men with hemophilia wh

  8. Determination of the M-matrix in d-. cap alpha. elastic scattering from a complete set of experiments

    Energy Technology Data Exchange (ETDEWEB)

    Elsener, K.; Grueebler, W.; Sperisen, F.; Ghazi-Wakili, K.; Koenig, V.; Schmelzbach, P.A.; Vuaridel, B.; Bittcher, M.; Singy, D.; Ulbricht, J.

    1988-05-02

    Six polarization transfer coefficients of the d-..cap alpha.. elastic scattering have been measured at an incident deuteron energy of 11.9 MeV and a scattering angle theta/sub lab/ = 37.3/sup 0/. Together with earlier data on cross section and analyzing powers, a complete set of measurements allows to deduce the d-..cap alpha.. M-matrix directly from experiment.

  9. A KCNJ6 gene polymorphism modulates theta oscillations during reward processing.

    Science.gov (United States)

    Kamarajan, Chella; Pandey, Ashwini K; Chorlian, David B; Manz, Niklas; Stimus, Arthur T; Edenberg, Howard J; Wetherill, Leah; Schuckit, Marc; Wang, Jen-Chyong; Kuperman, Samuel; Kramer, John; Tischfield, Jay A; Porjesz, Bernice

    2016-12-16

    Event related oscillations (EROs) are heritable measures of neurocognitive function that have served as useful phenotype in genetic research. A recent family genome-wide association study (GWAS) by the Collaborative Study on the Genetics of Alcoholism (COGA) found that theta EROs during visual target detection were associated at genome-wide levels with several single nucleotide polymorphisms (SNPs), including a synonymous SNP, rs702859, in the KCNJ6 gene that encodes GIRK2, a G-protein inward rectifying potassium channel that regulates excitability of neuronal networks. The present study examined the effect of the KCNJ6 SNP (rs702859), previously associated with theta ERO to targets in a visual oddball task, on theta EROs during reward processing in a monetary gambling task. The participants were 1601 adolescent and young adult offspring within the age-range of 17-25years (800 males and 801 females) from high-dense alcoholism families as well as control families of the COGA prospective study. Theta ERO power (3.5-7.5Hz, 200-500ms post-stimulus) was compared across genotype groups. ERO theta power at central and parietal regions increased as a function of the minor allele (A) dose in the genotype (AA>AG>GG) in both loss and gain conditions. These findings indicate that variations in the KCNJ6 SNP influence magnitude of theta oscillations at posterior loci during the evaluation of loss and gain, reflecting a genetic influence on neuronal circuits involved in reward-processing. Increased theta power as a function of minor allele dose suggests more efficient cognitive processing in those carrying the minor allele of the KCNJ6 SNPs. Future studies are needed to determine the implications of these genetic effects on posterior theta EROs as possible "protective" factors, or as indices of delays in brain maturation (i.e., lack of frontalization).

  10. The electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, S. [RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton (United States)]|[Tsukuba Univ. (Japan). Graduate School of Pure and Applied Sciences; Horsley, R.; Zanotti, J. [Edinburgh Univ. (United Kingdom). School of Physics; Izubuchi, T. [RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton (United States)]|[Kanazawa Univ. (Japan). Inst. for Theoretical Physics; Nakamura, Y.; Pleiter, D.; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division. Dept. of Mathematical Sciences

    2008-07-15

    We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N{sub f}=2 flavors of dynamical quarks at imaginary vacuum angle {theta}. The calculation proceeds via the CP odd form factor F{sub 3}. A novel feature of our calculation is that we use partially twisted boundary conditions to extract F{sub 3} at zero momentum transfer. As a byproduct, we test the QCD vacuum at nonvanishing {theta}. (orig.)

  11. Differentiating neutrino models on the basis of $\\theta_{13}$ and lepton flavor violation

    Energy Technology Data Exchange (ETDEWEB)

    Albright, Carl H.; /Northern Illinois U. /Fermilab

    2008-03-01

    The authors show how models of neutrino masses and mixings can be differentiated on the basis of their predictions for {theta}{sub 13} and lepton flavor violation in radiative charged lepton decays and {mu} - e conversion. They illustrate the lepton flavor violation results for five predictive SO(10) SUSY GUT models and point out the relative importance of their heavy right-handed neutrino mass spectra and {theta}{sub 13} predictions.

  12. Pentaquarks in a relativistic quark model and nature of Theta-states

    CERN Document Server

    Gerasyuta, S M

    2003-01-01

    The relativistic five-quark equations are found in the framework of the dispersion relation technique. The solutions of these equations using the method based on the extraction of the leading singularities of the amplitudes are obtained. The five-quark amplitudes for the low-lying pentaquarks including the u, d, s- quarks are calculated. The poles of these amplitudes determine the masses of Theta-pentaquarks. The mass spectra of the isotensor Theta-pentaquarks are calculated.

  13. QCD $\\theta$-vacua from the chiral limit to the quenched limit

    CERN Document Server

    Mameda, Kazuya

    2014-01-01

    We investigate the dependence of the QCD vacuum structure on $\\theta$-angle and quark mass, using the Veneziano$-$Di-Vecchia model. Although the Veneziano$-$Di-Vecchia model is a chiral effective model, it contains the topological property of the pure Yang$-$Mills theory. It is shown that within this model, the ground state energies for all $\\theta$ are continuous functions of quark mass from the chiral limit to the quenched limit, including the first order phase transition at $\\theta = \\pi$ for arbitrary finite mass. Besides, based on this effective model, we discuss (i) how the ground state depends on quark mass, and (ii) why the phase transition at $\\theta = \\pi$ is caused both in the chiral and quenched limit. In order to analyze the relation between quark mass and $\\theta$-vacua, we calculate chiral condensate as a function of quark mass. We also give a unified understanding of the phase transitions at $\\theta = \\pi$ in the chiral and quenched limit, making reference to the metastable states included inn...

  14. Frontal theta links prediction errors to behavioral adaptation in reinforcement learning.

    Science.gov (United States)

    Cavanagh, James F; Frank, Michael J; Klein, Theresa J; Allen, John J B

    2010-02-15

    Investigations into action monitoring have consistently detailed a frontocentral voltage deflection in the event-related potential (ERP) following the presentation of negatively valenced feedback, sometimes termed the feedback-related negativity (FRN). The FRN has been proposed to reflect a neural response to prediction errors during reinforcement learning, yet the single-trial relationship between neural activity and the quanta of expectation violation remains untested. Although ERP methods are not well suited to single-trial analyses, the FRN has been associated with theta band oscillatory perturbations in the medial prefrontal cortex. Mediofrontal theta oscillations have been previously associated with expectation violation and behavioral adaptation and are well suited to single-trial analysis. Here, we recorded EEG activity during a probabilistic reinforcement learning task and fit the performance data to an abstract computational model (Q-learning) for calculation of single-trial reward prediction errors. Single-trial theta oscillatory activities following feedback were investigated within the context of expectation (prediction error) and adaptation (subsequent reaction time change). Results indicate that interactive medial and lateral frontal theta activities reflect the degree of negative and positive reward prediction error in the service of behavioral adaptation. These different brain areas use prediction error calculations for different behavioral adaptations, with medial frontal theta reflecting the utilization of prediction errors for reaction time slowing (specifically following errors), but lateral frontal theta reflecting prediction errors leading to working memory-related reaction time speeding for the correct choice.

  15. Principal and Boolean congruences on \\theta-valued Lukasiewicz-Moisil algebras

    CERN Document Server

    Figallo, A V

    2012-01-01

    The first system of many-valued logic was introduced by J. Lukasiewicz, his motivation was of philosophical nature as he was looking for an interpretation of the concepts of possibility and necessity. Since then, plenty of research has been developed in this area. In 1968, when Gr.C. Moisil came across Zadeh's fuzzy set theory he found the motivation he had been looking for in order to legitimate the introduction and study of infinitely-valued Lukasiewicz algebras, so he defined \\theta-valued Lukasiewicz algebras (or LM\\theta-algebras, for short) (without negation), where \\theta is the order type of a chain. In this article, our main interest is to investigate the principal and Boolean congruences and \\theta-congruences on LM\\theta-algebras. In order to do this we take into account a topological duality for these algebras obtained in (A.V. Figallo, I. Pascual, A. Ziliani, A Duality for \\theta-Valued Lukasiewicz-Moisil Algebras and Aplicattions. J. LMult- Valued Logic & Soft Computing. Vol. 16, pp 303-322....

  16. $\\Delta$-N Electromagnetic Transition

    CERN Document Server

    Loan, M

    1999-01-01

    The EM ratio for a free Delta electromagnetic transition is discussed within the frame work of nonrelativistic approach. Such an approach gives a good account of data for a free Delta but is less important for an intrinsically relativistic nuclear many body problem.

  17. Mida pakub Delta? / Teele Kurm

    Index Scriptorium Estoniae

    Kurm, Teele

    2011-01-01

    Politsei- ja Piirivalveamet võtab kasutusele ühise Siseministeeriumi infotehnoloogia- ja arenduskeskuse ning Webmedia AS koostööna loodud dokumendihaldussüsteemi Delta. Kust sai Delta oma nime? Projekti "Dokumendihaldussüsteemi juurutamine Siseministeeriumi haldusalas" eesmärgid

  18. Delta Electroproduction in 12-C

    Energy Technology Data Exchange (ETDEWEB)

    Steven McLauchlan

    2003-01-31

    The Delta-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the delta mass indicating that this potential is dependent on the momentum of the delta. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the delta resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4(pie) acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the delta mass was only observed in the exclusive measurements indicating that the delta-nucleus potential is affected by the momentum of the delta.

  19. Mida pakub Delta? / Teele Kurm

    Index Scriptorium Estoniae

    Kurm, Teele

    2011-01-01

    Politsei- ja Piirivalveamet võtab kasutusele ühise Siseministeeriumi infotehnoloogia- ja arenduskeskuse ning Webmedia AS koostööna loodud dokumendihaldussüsteemi Delta. Kust sai Delta oma nime? Projekti "Dokumendihaldussüsteemi juurutamine Siseministeeriumi haldusalas" eesmärgid

  20. Mackenzie River Delta, Canada

    Science.gov (United States)

    2007-01-01

    The Mackenzie River in the Northwest Territories, Canada, with its headstreams the Peace and Finley, is the longest river in North America at 4241 km, and drains an area of 1,805,000 square km. The large marshy delta provides habitat for migrating Snow Geese, Tundra Swans, Brant, and other waterfowl. The estuary is a calving area for Beluga whales. The Mackenzie (previously the Disappointment River) was named after Alexander Mackenzie who travelled the river while trying to reach the Pacific in 1789. The image was acquired on August 4, 2005, covers an area of 55.8 x 55.8 km, and is located at 68.6 degrees north latitude, 134.7 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  1. DELTA 3D PRINTER

    Directory of Open Access Journals (Sweden)

    ȘOVĂILĂ Florin

    2016-07-01

    Full Text Available 3D printing is a very used process in industry, the generic name being “rapid prototyping”. The essential advantage of a 3D printer is that it allows the designers to produce a prototype in a very short time, which is tested and quickly remodeled, considerably reducing the required time to get from the prototype phase to the final product. At the same time, through this technique we can achieve components with very precise forms, complex pieces that, through classical methods, could have been accomplished only in a large amount of time. In this paper, there are presented the stages of a 3D model execution, also the physical achievement after of a Delta 3D printer after the model.

  2. Assembly, intracellular processing, and expression at the cell surface of the human alpha beta T cell receptor/CD3 complex. Function of the CD3-zeta chain

    DEFF Research Database (Denmark)

    Geisler, C; Kuhlmann, J; Rubin, B

    1989-01-01

    The TCR/CD3 complex is a multimeric protein complex composed of a minimum of seven transmembrane chains (TCR alpha beta-CD3 gamma delta epsilon zeta 2). Whereas earlier studies have demonstrated that both the TCR-alpha and -beta chains are required for the cell surface expression of the TCR/CD3 c...... to form the heptameric complex (TCR alpha beta-CD3 gamma delta epsilon----TCR alpha beta-CD3 gamma delta epsilon 2); and 5) CD3-zeta is required for the export of the TCR/CD3 complex from the endoplasmic reticulum to the Golgi apparatus for subsequent processing....

  3. Upsilon NU: Our chapter in Sigma Theta Tau Internacional Upsilon NU: nuestro capítulo en Sigma Theta Tau International

    Directory of Open Access Journals (Sweden)

    GARZÓN ALARCÓN NELLY

    2008-07-01

    Full Text Available ALa Sociedad de Honor de Enfermería, Sigma Theta Tau Internacional, es una organización que nace y vive para desarrollar el conocimiento y la ciencia de enfermería como fundamentos del liderazgo y la búsqueda de la excelencia en el cuidado de la persona, la familia y la comunidad.

  4. Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure.

    Science.gov (United States)

    Kubota, Y; Sato, W; Toichi, M; Murai, T; Okada, T; Hayashi, A; Sengoku, A

    2001-04-01

    Frontal midline theta rhythm (Fm theta), recognized as distinct theta activity on EEG in the frontal midline area, reflects mental concentration as well as meditative state or relief from anxiety. Attentional network in anterior frontal lobes including anterior cingulate cortex is suspected to be the generator of this activity, and the regulative function of the frontal neural network over autonomic nervous system (ANS) during cognitive process is suggested. However no studies have examined peripheral autonomic activities during Fm theta induction, and interaction of central and peripheral mechanism associated with Fm theta remains unclear. In the present study, a standard procedure of Zen meditation requiring sustained attention and breath control was employed as the task to provoke Fm theta, and simultaneous EEG and ECG recordings were performed. For the subjects in which Fm theta activities were provoked (six men, six women, 48% of the total subjects), peripheral autonomic activities were evaluated during the appearance of Fm theta as well as during control periods. Successive inter-beat intervals were measured from the ECG, and a recently developed method of analysis by Toichi et al. (J. Auton. Nerv. Syst. 62 (1997) 79-84) based on heart rate variability was used to assess cardiac sympathetic and parasympathetic functions separately. Both sympathetic and parasympathetic indices were increased during the appearance of Fm theta compared with control periods. Theta band activities in the frontal area were correlated negatively with sympathetic activation. The results suggest a close relationship between cardiac autonomic function and activity of medial frontal neural circuitry.

  5. Heavy quark analogues of the {theta} and their excitations

    Energy Technology Data Exchange (ETDEWEB)

    Maltman, Kim [Department of Mathematics and Statistics, York University, 4700 Keele St., Toronto, ON, M3J 1P3 (Canada) and CSSM, University of Adelaide, Adelaide, SA 5005 (Australia)]. E-mail: kmaltman@yorku.ca

    2004-12-23

    Predictions for the low-lying excitation spectrum of positive parity pentaquark systems containing one c-bar or b-bar antiquark and four light u, d quarks are obtained in the quark model picture for models with spin-dependent interactions given either by effective color-magnetic (CM) exchange or effective Goldstone boson (GB) exchange. For the GB model, 4 excited states are predicted to lie within approx. = m{sub {delta}}-m{sub N} of the J{sup P}=1/2{sup +} ground state while, for the CM model, 10 states are expected in the same range. Both the lowest excitation energy and the relative splittings are much smaller in the CM case. These predictions are on the same footing as those for the analogous splittings in the non-exotic baryon sector and, as such, provide a means of not only testing the models, but potentially ruling out either one, or both.

  6. Different types of theta rhythmicity are induced by social and fearful stimuli in a network associated with social memory.

    Science.gov (United States)

    Tendler, Alex; Wagner, Shlomo

    2015-02-16

    Rhythmic activity in the theta range is thought to promote neuronal communication between brain regions. In this study, we performed chronic telemetric recordings in socially behaving rats to monitor electrophysiological activity in limbic brain regions linked to social behavior. Social encounters were associated with increased rhythmicity in the high theta range (7-10 Hz) that was proportional to the stimulus degree of novelty. This modulation of theta rhythmicity, which was specific for social stimuli, appeared to reflect a brain-state of social arousal. In contrast, the same network responded to a fearful stimulus by enhancement of rhythmicity in the low theta range (3-7 Hz). Moreover, theta rhythmicity showed different pattern of coherence between the distinct brain regions in response to social and fearful stimuli. We suggest that the two types of stimuli induce distinct arousal states that elicit different patterns of theta rhythmicity, which cause the same brain areas to communicate in different modes.

  7. WORLD DELTAS AND THEIR EVOLUTION

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In August 1998, an international symposium on the world deltas was held in New Orleans, Louisiana, USA. This symposium attracted discussion about more than 25 deltas from around the world with emphasis placed on those that are most densely populated and impacted by humans. Keynote papers printed details about the physical, biological, engineering and socioeconomic aspects of six deltas including the Mississippi, Nile, Ganges-Brahmaputra, Rhine-Meuse, Changjiang and Po. The main purpose of this symposium was to inform scientists, engineers and decision-makers about information that is currently available and to provide them a basis for working in such environments.

  8. Dynamical Casimir effect with $\\delta-\\delta^{\\prime}$ mirrors

    CERN Document Server

    Silva, Jeferson Danilo L; Alves, Danilo T

    2016-01-01

    We calculate the spectrum and the total rate of created particles for a real massless scalar field in $1+1$ dimensions, in the presence of a partially transparent moving mirror simulated by a Dirac $\\delta-\\delta^{\\prime}$ point interaction. We show that, strikingly, a partially reflecting mirror can produce a larger number of particles in comparison with a perfectly reflecting one. In the limit of a perfect mirror, our formulas recover those found in the literature for the Robin boundary condition.

  9. Mast cells express novel functional IL-15 receptor alpha isoforms.

    Science.gov (United States)

    Bulanova, Elena; Budagian, Vadim; Orinska, Zane; Krause, Hans; Paus, Ralf; Bulfone-Paus, Silvia

    2003-05-15

    Mast cells previously have been reported to be regulated by IL-15 and to express a distinct IL-15R, termed IL-15RX. To further examine IL-15 binding and signaling in mast cells, we have studied the nature of the IL-15R and some of its biological activities in these cells. In this study, we report the existence of three novel isoforms of the IL-15R alpha chain in murine bone marrow-derived mast cells as a result of an alternative exon-splicing mechanism within the IL-15R alpha gene. These correspond to new mRNA transcripts lacking exon 4; exons 3 and 4; or exons 3, 4, and 5 (IL-15R alpha Delta 4, IL-15R alpha Delta 3,4, IL-15R alpha Delta 3,4,5). After transient transfection in COS-7 cells, all IL-15R alpha isoforms associate with the Golgi apparatus, the endoplasmic reticulum, the perinuclear space, and the cell membrane. Analysis of glycosylation pattern demonstrates the usage of a single N-glycosylation site, while no O-glycosylation is observed. Importantly, IL-15 binds with high affinity to, and promotes the survival of, murine BA/F3 cells stably transfected with the IL-15R alpha isoforms. Furthermore, we report that signaling mediated by IL-15 binding to the newly identified IL-15R alpha isoforms involves the phosphorylation of STAT3, STAT5, STAT6, Janus kinase 2, and Syk kinase. Taken together, our data indicate that murine mast cells express novel, fully functional IL-15R alpha isoforms, which can explain the selective regulatory effects of IL-15 on these cells.

  10. Refinement of the composition and structure of YBaCo{sub 4-x}Al{sub x}O{sub 7+{delta}} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Podberezskaya, N. V., E-mail: podberez@niic.nsc.ru; Kozeeva, L. P.; Kameneva, M. Yu.; Smolentsev, A. I.; Alekseev, A. V.; Lavrov, A. N. [Russian Academy of Sciences, Nikolaev Institute of Inorganic Chemistry, Siberian Branch (Russian Federation)

    2011-05-15

    YBa(Co{sub 4-x}Al{sub x})O{sub 7+{delta}} (114Y) crystals have been grown in the Y-Ba-Co-O system by spontaneous crystallization from a slowly cooled nonstoichiometric melt. To change the oxygen content, the crystals were isothermally annealed in air in the range of 280-490 Degree-Sign C. The crystals grown were characterized by scanning electron microscopy and powder X-ray diffraction. According to the data of an X-ray spectroscopic quantitative microprobe analysis, the average compositions of 'as-grown' and oxygen-saturated crystals were Y{sub 1.04}Ba{sub 1}Co{sub 3.54}Al{sub 0.50}O{sub 7.8} and Y{sub 1.02}Ba{sub 1}Co{sub 3.55}Al{sub 0.51}O{sub 8.4}, respectively. The refinement of the crystal structure after saturation on an automatic Bruker X8APEX diffractometer with a CCD detector (MoK{alpha} radiation, graphite monochromator, {theta}{sub max} = 32.54 Degree-Sign , sp. gr. P6{sub 3}mc, a = 6.2746(9), c = 10.257(3) Angstrom-Sign , V = 349.71(13) Angstrom-Sign {sup 3}, Z = 2, d{sub calcd} = 5.220 g/cm{sup 3}) reveals the location of Al in two independent positions of Co atoms and yields the general formula of the compound as YBaCo{sub 3.26}Al{sub 0.74}O{sub 7}. Problems related to the difference in the compositions obtained by different methods are discussed.

  11. Revised fits to $\\Delta\\alpha/\\alpha$ in consistency with the accelerating universe

    CERN Document Server

    Fujii, Yasunori

    2008-01-01

    An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all in consistency with the accelerating universe.

  12. Revised fits to {delta}{alpha}/{alpha} in consistency with the accelerating universe

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Yasunori [Advanced Research Institute for Science and Engineering, Waseda University, 169-8555 Tokyo (Japan)], E-mail: fujii@e07.itscom.net

    2009-01-19

    An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all in consistency with the accelerating universe.

  13. A statistical analysis of the data of Delta \\alpha/ alpha from quasar absorption systems

    CERN Document Server

    Landau, Susana J

    2008-01-01

    We analyze different data of the variation of the fine structure constant obtained with different methods to check their consistency.We test consistency using the modified Student test and confidence intervals. We split the data sets in smaller intervals. A criterion for this selection is proposed. Results show consistency for reduced intervals for each pair of data sets considered. Results are at variance with the ones obtained considering mean values over the whole interval.

  14. Median raphe stimulation-induced motor inhibition concurrent with suppression of type 1 and type 2 hippocampal theta.

    Science.gov (United States)

    Bland, Brian H; Bland, Cheryl E; MacIver, M Bruce

    2016-03-01

    This study investigated behavioral, anatomical and electrophysiological effects produced by electrical stimulation of posterior hypothalamic (PH) or median raphe (MR) nuclei, independently and during combined stimulation of both PH and MR. These three stimulation conditions were applied during spontaneous behavior in an open field and during PH stimulation-induced wheel running, while simultaneously recording hippocampal (HPC) field activity. An additional objective was to determine the effects of MR stimulation on Type 1 movement related theta and Type 2 sensory processing related theta. To achieve the latter, when behavioral studies were completed we studied the same rats under urethane anesthesia and then during urethane anesthesia with the addition of atropine sulfate (ATSO4). Here we demonstrated that electrical stimulation of a localized region of the MR nucleus resulted in a profound inhibition of both spontaneously occurring theta related motor behaviors and the theta related motor behaviors induced by electrical stimulation of the PH nucleus. Furthermore, this motor inhibition occurred concurrently with strong suppression of hippocampal theta field oscillations in the freely moving rat, a condition where the theta recorded is Type 2 sensory processing theta occurring coincidently with Type 1 movement related theta (Bland, 1986). Our results indicate that motor inhibition resulted from stimulation of neurons located in the mid central region of the MR, while stimulation in adjacent regions produced variable responses, including movements and theta activity. The present study provided evidence that the pharmacological basis of the suppression of Type 2 sensory processing HPC theta was cholinergic. However, MR inhibition of PH-induced wheel running was not affected by cholinergic blockade, which blocks Type 2 theta, indicating that MR stimulation-induced motor inhibition also requires the suppression of Type 1 theta.

  15. The driving system for hippocampal theta in the brainstem: an examination by single neuron recording in urethane-anesthetized rats.

    Science.gov (United States)

    Takano, Yuji; Hanada, Yasuhiro

    2009-05-08

    The brainstem has been shown to be involved in generating hippocampal theta; however, which brainstem region plays the most important role in generating the rhythm has remained unclear. To reveal which brainstem region triggers the theta, the hippocampal local field potential was recorded simultaneously with single unit activity in the brainstem of urethane-anesthetized rat. The firing latencies before theta onset and offset were compared among recording sites (deep mesencephalic nucleus, DpMe; pedunculopontine tegmental nucleus, PPT; nucleus pontis oralis, PnO). We examined the activities of 59 cells; PPT showed the highest proportion of neurons changing their firing rates at theta onset (14/16, 87.5%). The proportion in the PnO was 14/22 (63.6%), but the neurons in the PnO showed the earliest changes in latencies (0.57s before theta onset). The change in the PPT was 0.96s after theta onset. Regarding the theta offset, the PPT showed the highest proportion of neurons changing their firing rates at theta offset (9/16, 56.3%; the proportion in the PnO was 5/22, 22.7%), but the difference in latent time was not significant among recorded regions. The neurons in the DpMe did not show any remarkable firing tendency at theta onset and offset. From these results, we propose a driving system of hippocampal theta, in which neurons in the PnO first trigger the theta onset and then those in the PPT maintain the theta by activating broadly the brainstem areas for the wave.

  16. Solving the Puzzle of the Massive Star System Theta 2 Orionis A

    CERN Document Server

    Petit, V; Cohen, D H; Townsend, R H D; Leutenegger, M A; Savoy, M R; Fehon, G; Cartagena, C A

    2012-01-01

    The young O9.5 V spectroscopic binary Theta 2 Ori A shows moderately hard X-ray emission and relatively narrow X-ray lines, suggesting that it may be a Magnetically Confined Wind Shock (MCWS) source, similar to its more massive analogue Theta 1 Ori C. X-ray flares occurring near periastron led to the suggestion that the flares are produced via magnetic reconnection as magnetospheres on both components of the Theta 2 Ori A binary interact at closest approach. We use a series of high-resolution spectropolarimetric observations of Theta 2 Ori A to place an upper limit on the magnetic field strength of 135 G (95% credible region). Such a weak dipole field would not produce magnetic confinement, or a large magnetosphere. A sub-pixel analysis of the Chandra ACIS images of Theta 2 Ori A obtained during quiescence and flaring show that the hard, flaring X-rays are offset from the soft, quiescent emission by 0.4 arcsec. If the soft emission is associated with the A1/A2 spectroscopic binary, the offset and position ang...

  17. Mathematically gifted adolescents mobilize enhanced workspace configuration of theta cortical network during deductive reasoning.

    Science.gov (United States)

    Zhang, L; Gan, J Q; Wang, H

    2015-03-19

    Previous studies have established the importance of the fronto-parietal brain network in the information processing of reasoning. At the level of cortical source analysis, this eletroencepalogram (EEG) study investigates the functional reorganization of the theta-band (4-8Hz) neurocognitive network of mathematically gifted adolescents during deductive reasoning. Depending on the dense increase of long-range phase synchronizations in the reasoning process, math-gifted adolescents show more significant adaptive reorganization and enhanced "workspace" configuration in the theta network as compared with average-ability control subjects. The salient areas are mainly located in the anterior cortical vertices of the fronto-parietal network. Further correlation analyses have shown that the enhanced workspace configuration with respect to the global topological metrics of the theta network in math-gifted subjects is correlated with the intensive frontal midline theta (fm theta) response that is related to strong neural effort for cognitive events. These results suggest that by investing more cognitive resources math-gifted adolescents temporally mobilize an enhanced task-related global neuronal workspace, which is manifested as a highly integrated fronto-parietal information processing network during the reasoning process.

  18. Patterns of Theta Activity in Limbic Anxiety Circuit Preceding Exploratory Behavior in Approach-Avoidance Conflict

    Science.gov (United States)

    Jacinto, Luis R.; Cerqueira, João J.; Sousa, Nuno

    2016-01-01

    Theta oscillations within the hippocampus-amygdala-medial prefrontal cortex (HPC-AMY-mPFC) circuit have been consistently implicated in the regulation of anxiety behaviors, including risk-assessment. To study if theta activity during risk-assessment was correlated with exploratory behavior in an approach/avoidance paradigm we recorded simultaneous local field potentials from this circuit in rats exploring the elevated-plus maze (EPM). Opposing patterns of power variations in the ventral hippocampus (vHPC), basolateral amygdala (BLA), and prelimbic (PrL) mPFC, but not in the dorsal hippocampus (dHPC), during exploratory risk-assessment of the open arms preceded further exploration of the open arms or retreat back to the safer closed arms. The same patterns of theta power variations in the HPC-BLA-mPFC(PrL) circuit were also displayed by animals submitted to chronic unpredictable stress protocol known to induce an anxious state. Diverging patterns of vHPC-mPFC(PrL) theta coherence were also significantly correlated with forthcoming approach or avoidance behavior in the conflict situation in both controls and stressed animals; interestingly, vHPC-BLA, and BLA-mPFC(PrL) theta coherence correlated with future behavior only in stressed animals, underlying the pivotal role of the amygdala on the stress response. PMID:27713693

  19. Patterns of Theta Activity in Limbic Anxiety Circuit Preceding Exploratory Behavior in Approach-Avoidance Conflict

    Directory of Open Access Journals (Sweden)

    Luis R Jacinto

    2016-09-01

    Full Text Available Theta oscillations within the hippocampus-amygdala-medial prefrontal cortex (HPC-AMY-mPFC(PrL circuit have been consistently implicated in the regulation of anxiety behaviors, including risk-assessment. To study if theta activity during risk-assessment was correlated with exploratory behavior in an approach/avoidance paradigm we recorded simultaneous local field potentials from this circuit in rats exploring the elevated-plus maze (EPM. Opposing patterns of power variations in the ventral hippocampus (vHPC, basolateral amygdala (BLA and prelimbic (PrL mPFC, but not in the dorsal hippocampus (dHPC, during exploratory risk-assessment of the open arms preceded further exploration of the open arms or retreat back to the safer closed arms. The same patterns of theta power variations in the HPC-BLA-mPFC(PrL circuit were also displayed by animals submitted to chronic unpredictable stress protocol known to induce an anxious state. Diverging patterns of vHPC-mPFC(PrL theta coherence were also significantly correlated with forthcoming approach or avoidance behavior in the conflict situation in both controls and stressed animals; interestingly, vHPC-BLA and BLA-mPFC(PrL theta coherence correlated with future behavior only in stressed animals, underlying the pivotal role of the amygdala on the stress response.

  20. Reevaluation of the role of DNA polymerase theta in somatic hypermutation of immunoglobulin genes.

    Science.gov (United States)

    Martomo, Stella A; Saribasak, Huseyin; Yokoi, Masayuki; Hanaoka, Fumio; Gearhart, Patricia J

    2008-09-01

    DNA polymerase theta has been implicated in the process of somatic hypermutation in immunoglobulin variable genes based on several reports of alterations in the frequency and spectra of mutations from Polq(-/-) mice. However, these studies have contrasting results on mutation frequencies and the types of nucleotide substitutions, which question the role of polymerase theta in hypermutation. DNA polymerase eta has a dominant effect on mutation and may substitute in the absence of polymerase theta to affect the pattern. Therefore, we have examined mutation in mice deficient for both polymerases theta and eta. The mutation frequencies in rearranged variable genes from Peyer's patches were similar in wild type, Polq(-/-), Polh(-/-), and Polq(-/-)Polh(-/-) mice. The types of substitutions were also similar between wild type and Polq(-/-) clones, and between Polh(-/-) and Polq(-/-)Polh(-/-) clones. Furthermore, there was no difference in heavy chain class switching in splenic B cells from the four groups of mice. These results indicate that polymerase theta does not play a significant role in the generation of somatic mutation in immunoglobulin genes.

  1. Lepton mixing angle {theta}{sub 13} = 0 with a horizontal symmetry D{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Grimus, W. E-mail: walter.grimus@univie.ac.at; Joshipura, A.S.; Kaneko, S.; Lavoura, L.; Tanimoto, M

    2004-07-01

    We discuss a model for the lepton sector based on the seesaw mechanism and on a D{sub 4} family symmetry. The model predicts the mixing angle {theta}{sub 13} to vanish. The solar mixing angle {theta}{sub 12} is free-it will in general be large if one does not invoke fine tuning. The model has an enlarged scalar sector with three Higgs doublets, together with two real scalar gauge singlets {chi}{sub i} (i = 1,2) which have vacuum expectation values {chi}{sub i0} at the seesaw scale. The atmospheric mixing angle {theta}{sub 23} is given by tan {theta}{sub 23} = X{sub 20}/{chi}{sub 10}, and it is maximal if the Lagrangian is D{sub 4}-invariant; but D{sub 4} may be broken softly, by a term of dimension two in the scalar potential, and then {chi}{sub 20} becomes different from {chi}{sub 10}. Thus, the strength of the soft D{sub 4} breaking controls the deviation of {theta}{sub 23} from {pi}/4. The model predicts a normal neutrino mass spectrum (m{sub 3} > m{sub 2} > m{sub 1}) and allows successful leptogenesis if m{sub 1} {approx} 4 x 10{sup -3}eV; these properties of the model are independent of the presence and strength of the soft D{sub 4} breaking. (author)

  2. Search for $\\Theta^{++}$ Pentaquarks in the Exclusive Reaction $\\gamma p\\to K^+K^-p$

    Energy Technology Data Exchange (ETDEWEB)

    V. Kubarovsky; Marco Battaglieri; Raffaella De Vita; John Goett; Lei Guo; Gordon Mutchler; Paul Stoler; Dennis Weygand; Pawel Ambrozewicz; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; V. Batourine; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Eric Clinton; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; Volker Crede; John Cummings; Rita De Masi; Daniel Dale; Enzo De Sanctis; Pavel Degtiarenko; Alexandre Deur; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Herbert Funsten; Marianna Gabrielyan; Liping Gan; Michel Garcon; Ashot Gasparian; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; Oleksandr Glamazdin; John Goetz; Evgueni Golovatch; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Rafael Hakobyan; John Hardie; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Franz Klein; Friedrich Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ji Li; Kenneth Livingston; Hai-jiang Lu; Marion MacCormick; Nikolai Markov; Bryan McKinnon; Bernhard Mecking; Joseph Melone; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Vasiliy Mochalov; Viktor Mokeev; Ludyvine Morand; Steven Morrow; Maryam Moteabbed; Pawel Nadel-Turonski; Itaru Nakagawa; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Igor Strakovski; Steffen Strauch; Mauro Taiuti; David Tedeschi; Aram Teymurazyan; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Lawrence Weinstein; Michael Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao

    2006-04-28

    The reaction {gamma}p {yields} K{sup +}K{sup -}p was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a {Theta}{sup ++} pentaquark, a narrow doubly charged baryon state having strangeness S = +1 and isospin I = 1, in the pK{sup +} invariant mass spectrum. No statistically significant evidence of a {Theta}{sup ++} was found. Upper limits on the total and differential production cross section for the reaction {gamma}p {yields} K{sup -}{Theta}{sup ++} were obtained in the mass range from 1.5 to 2.0 GeV/c{sup 2}, with an upper limit of about 0.15 nb, 95% C.L. for a narrow resonance with a mass M{sub {Theta}{sup ++}} = 1.54 GeV/c{sup 2}. This result places a very stringent upper limit on the {Theta}{sup ++} width.

  3. PARAMETRIC DESIGN OF DELTA ROBOT

    Directory of Open Access Journals (Sweden)

    Mert Gürgen

    2016-09-01

    Full Text Available This article describes a sophisticated determination and presentation of a workspace volume for a delta robot, with consideration of its kinematic behavior. With the help of theoretical equations, optimization is performed with the aid of the stiffness and dexterity analysis. Theoretical substructure is coded in Matlab and three-dimensional (3D data for delta robot are developed in computer-aided design (CAD environment. In later stages of the project, both 3D and theoretical data are linked together and thus, with the changing design parameter of the robot itself, the Solidworks CAD output adapts and regenerates output with a new set of parameters. To achieve an optimum workspace volume with predefined parameters, a different set of robot parameters are iterated through design optimization in Matlab, and the delta robot design is finalized and illustrated in the 3D CAD environment, Solidworks. This study provides a technical solution to accomplish a generic delta robot with optimized workspace volume.

  4. The W303 genetic background affects the isw2 delta mutant phenotype in Saccharomyces cerevisiae.

    Science.gov (United States)

    Trachtulcová, P; Frýdlová, I; Janatová, I; Dorosh, A; Hasek, J

    2003-01-01

    We performed detailed phenotypic analysis of the isw2 delta strains of the W303 genetic background and compared its results with those obtained previously in BY-derived genetic background. Shmoolike morphology was observed in the isw2 delta strain of alpha-mating type of the BY strains, but not in its W303-derived counterpart. On the other hand, derepression of a-specific genes in the isw2 delta (MAT alpha) strain was observed in both genetic backgrounds, although to a different extent. Unlike in BY-derived strain hyperactivation of the Ras2/cAMP pathway reduced invasiveness of the isw2 delta strain (MAT alpha) of the W303 background. Sensitivity to Calcofluor White indicating a cell wall-integrity defect was significantly increased in the isw2 delta strains of the W303 background in contrast to BY-derived strains. Our data indicate that the effects of the isw2 deletion strongly depend on the background in which the deletion, is made.

  5. A method of evaluating quantitative magnetospheric field models by an angular parameter alpha

    Science.gov (United States)

    Sugiura, M.; Poros, D. J.

    1979-01-01

    The paper introduces an angular parameter, termed alpha, which represents the angular difference between the observed, or model, field and the internal model field. The study discusses why this parameter is chosen and demonstrates its usefulness by applying it to both observations and models. In certain areas alpha is more sensitive than delta-B (the difference between the magnitude of the observed magnetic field and that of the earth's internal field calculated from a spherical harmonic expansion) in expressing magnetospheric field distortions. It is recommended to use both alpha and delta-B in comparing models with observations.

  6. First Measurement of \\theta_13 from Delayed Neutron Capture on Hydrogen in the Double Chooz Experiment

    CERN Document Server

    Abe, Y; Anjos, J C dos; Barriere, J C; Bergevin, M; Bernstein, A; Bezerra, T J C; Bezrukhov, L; Blucher, E; Bowden, N S; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chimenti, P; Classen, T; Collin, A P; Conover, E; Conrad, J M; Crespo-Anadón, J I; Crum, K; Cucoanes, A; Damon, E; Dawson, J V; Dazeley, S; Dietrich, D; Djurcic, Z; Dracos, M; Durand, V; Ebert, J; Efremenko, Y; Elnimr, M; Erickson, A; Etenko, A; Fallot, M; Fechner, M; von Feilitzsch, F; Felde, J; Fernandes, S M; Fischer, V; Franco, D; Franke, A J; Franke, M; Furuta, H; Gama, R; Gil-Botella, I; Giot, L; Göger-Neff, M; Gonzalez, L F G; Goodenough, L; Goodman, M C; Goon, J TM; Greiner, D; Haag, N; Habib, S; Hagner, C; Hara, T; Hartmann, F X; Haser, J; Hatzikoutelis, A; Hayakawa, T; Hofmann, M; Horton-Smith, G A; Hourlier, A; Ishitsuka, M; Jochum, J; Jollet, C; Jones, C L; Kaether, F; Kalousis, L N; Kamyshkov, Y; Kaplan, D M; Kawasaki, T; Keefer, G; Kemp, E; de Kerret, H; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Langbrandtner, C; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; López-Castaño, J M; LoSecco, J M; Lubsandorzhiev, B K; Lucht, S; McKee, D; Maeda, J; Maesano, C N; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Meyer, M; Miletic, T; Milincic, R; Miyata, H; Mueller, Th A; Nagasaka, Y; Nakajima, K; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Ostrovskiy, I; Palomares, C; Pepe, I M; Perasso, S; Perrin, P; Pfahler, P; Porta, A; Potzel, W; Pronost, G; Reichenbacher, J; Reinhold, B; Remoto, A; Röhling, M; Roncin, R; Roth, S; Rybolt, B; Sakamoto, Y; Santorelli, R; Sato, F; Schönert, S; Schoppmann, S; Schwetz, T; Shaevitz, M H; Shimojima, S; Shrestha, D; Sida, J-L; Sinev, V; Skorokhvatov, M; Smith, E; Spitz, J; Stahl, A; Stancu, I; Stokes, L F F; Strait, M; Stüken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Svoboda, R; Terao, K; Tonazzo, A; Toups, M; Thi, H H Trinh; Valdiviesso, G; Veyssiere, C; Wagner, S; Watanabe, H; White, B; Wiebusch, C; Winslow, L; Worcester, M; Wurm, M; Yermia, F; Zimmer, V

    2013-01-01

    The Double Chooz experiment has determined the value of the neutrino oscillation parameter $\\theta_{13}$ from an analysis of inverse beta decay interactions with neutron capture on hydrogen. This analysis uses a three times larger fiducial volume than the standard Double Chooz assessment, which is restricted to a region doped with gadolinium (Gd), yielding an exposure of 113.1 GW-ton-years. The data sample used in this analysis is distinct from that of the Gd analysis, and the systematic uncertainties are also largely independent, with some exceptions, such as the reactor neutrino flux prediction. A combined rate- and energy-dependent fit finds $\\sin^2 2\\theta_{13}=0.097\\pm 0.034(stat.) \\pm 0.034 (syst.)$, excluding the no-oscillation hypothesis at 2.0 \\sigma. This result is consistent with previous measurements of $\\sin^2 2\\theta_{13}$.

  7. Phase structure with nonzero $\\Theta_{\\rm QCD}$ and twisted mass fermions

    CERN Document Server

    Horkel, Derek P

    2015-01-01

    We determine the phase diagram and chiral condensate for lattice QCD with two flavors of twisted-mass fermions in the presence of nondegenerate up and down quarks, discretization errors and a nonzero value of $\\Theta_{\\rm QCD}$. Although such a theory has a complex action and cannot, at present, be simulated, the results are needed to understand how to tune to maximal twist in the presence of electromagnetism, a topic discussed in a companion paper. We find that, in general, the only phase structure is a first-order transition of finite length. Pion masses are nonvanishing throughout the phase plane except at the endpoints of the first-order line. Only for extremal values of the twist angle and $\\Theta_{\\rm QCD}$ ($\\omega=0$ or $\\pi/2$ and $\\Theta_{\\rm QCD}=0$ or $\\pi$) are there second-order transitions.

  8. Three-particle integrable systems with elliptic dependence on momenta and theta function identities

    Energy Technology Data Exchange (ETDEWEB)

    Aminov, G., E-mail: aminov@itep.ru [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation); Mironov, A., E-mail: mironov@itep.ru [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Theory Department, Lebedev Physics Institute, Moscow (Russian Federation); Morozov, A., E-mail: morozov@itep.ru [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Zotov, A., E-mail: zotov@itep.ru [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation); Steklov Mathematical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2013-11-04

    We claim that some non-trivial theta-function identities at higher genus can stand behind the Poisson commutativity of the Hamiltonians of elliptic integrable systems, which were introduced in [1,2] and are made from the theta-functions on Jacobians of the Seiberg–Witten curves. For the case of three-particle systems the genus-2 identities are found and presented in the Letter. The connection with the Macdonald identities is established. The genus-2 theta-function identities provide the direct way to construct the Poisson structure in terms of the coordinates on the Jacobian of the spectral curve and the elements of its period matrix. The Lax representations for the two-particle systems are also obtained.

  9. Three-particle Integrable Systems with Elliptic Dependence on Momenta and Theta Function Identities

    CERN Document Server

    Aminov, G; Morozov, A; Zotov, A

    2013-01-01

    We claim that some non-trivial theta-function identities at higher genus can stand behind the Poisson commutativity of the Hamiltonians of elliptic integrable systems, which are made from the theta-functions on Jacobians of the Seiberg-Witten curves. For the case of three-particle systems the genus-2 identities are found and presented in the paper. The connection with the Macdonald identities is established. The genus-2 theta-function identities provide the direct way to construct the Poisson structure in terms of the coordinates on the Jacobian of the spectral curve and the elements of its period matrix. The Lax representations for the two-particle systems are also obtained.

  10. The CP-odd sector and $\\theta$ dynamics in holographic QCD

    CERN Document Server

    Arean, Daniel; Jarvinen, Matti; Kiritsis, Elias

    2016-01-01

    The holographic model of V-QCD is used to analyze the physics of QCD in the Veneziano large-N limit. An unprecedented analysis of the CP-odd physics is performed going beyond the level of effective field theories. The structure of holographic saddle-points at finite $\\theta$ is determined, as well as its interplay with chiral symmetry breaking. Many observables (vacuum energy and higher-order susceptibilities, singlet and non-singlet masses and mixings) are computed as functions of $\\theta$ and the quark mass $m$. Wherever applicable the results are compared to those of chiral Lagrangians, finding agreement. In particular, we recover the Witten-Veneziano formula in the small $x\\to 0$ limit, we compute the $\\theta$-dependence of the pion mass and we derive the hyperscaling relation for the topological susceptibility in the conformal window in terms of the quark mass.

  11. Episodic sequence memory is supported by a theta-gamma phase code.

    Science.gov (United States)

    Heusser, Andrew C; Poeppel, David; Ezzyat, Youssef; Davachi, Lila

    2016-10-01

    The meaning we derive from our experiences is not a simple static extraction of the elements but is largely based on the order in which those elements occur. Models propose that sequence encoding is supported by interactions between high- and low-frequency oscillations, such that elements within an experience are represented by neural cell assemblies firing at higher frequencies (gamma) and sequential order is encoded by the specific timing of firing with respect to a lower frequency oscillation (theta). During episodic sequence memory formation in humans, we provide evidence that items in different sequence positions exhibit greater gamma power along distinct phases of a theta oscillation. Furthermore, this segregation is related to successful temporal order memory. Our results provide compelling evidence that memory for order, a core component of an episodic memory, capitalizes on the ubiquitous physiological mechanism of theta-gamma phase-amplitude coupling.

  12. Topological insulators and the QCD vacuum: the theta parameter as a Berry phase

    CERN Document Server

    Thacker, H B

    2013-01-01

    There is considerable evidence, based on large $N_c$ chiral dynamics, holographic QCD, and Monte Carlo studies, that the QCD vacuum is permeated by discrete quasivacua separated by domain walls across which the local value of the topological $\\theta$ parameter jumps by $\\pm2\\pi$. In the 2-dimensional $CP^{N-1}$ sigma model, a pointlike charge is a domain wall, and $\\theta$ describes the background electric flux and the polarization of charged pairs in the vacuum. We show that the screening process, and the role of $\\theta$ as an order parameter describing electric polarization, are naturally formulated in terms of Bloch wave eigenstates of the Dirac Hamiltonian in the background gauge field. This formulation is similar to the Berry phase description of electric polarization and quantized charge transport in topological insulators. The Bloch waves are quasiperiodic superpositions of localized Dirac zero modes. They define a Berry connection around the Brillouin zone of the zero mode band which describes the lo...

  13. Self-regulation of frontal-midline theta facilitates memory updating and mental set shifting

    Directory of Open Access Journals (Sweden)

    Stefanie eEnriquez-Geppert

    2014-12-01

    Full Text Available Frontal-midline (fm theta oscillations as measured via the electroencephalogram (EEG have been suggested as neural working language of executive functioning. Their power has been shown to increase when cognitive processing or task performance is enhanced. Thus, the question arises whether learning to increase fm-theta amplitudes would functionally impact the behavioral performance in tasks probing executive functions (EFs. Here, the effects of neurofeedback, a learning method to self-up-regulate fm-theta over frontal-midline electrodes, on the four most representative EFs, memory updating, set shifting, conflict monitoring, and motor inhibition are presented. Before beginning and after completing an individualized, eight-session gap-spaced neurofeedback intervention, the three-back, letter/number task-switching, Stroop, and stop-signal tasks were tested while measuring the EEG. Self-determined up-regulation of fm-theta and its putative role for executive functioning were compared to an active control group, the so-called pseudo-neurofeedback group. Task-related fm-theta activity after training differed significantly between groups. More importantly, though, after neurofeedback significantly enhanced behavioral performance was observed. The training group showed higher accuracy scores in the three-back task and reduced mixing and shifting costs in letter/number task-switching. However, this specific protocol type did not affect performance in tasks probing conflict monitoring and motor inhibition. Thus, our results suggest a modulation of proactive but not reactive mechanisms of cognitive control. In sum, the modulation of fm-theta via neurofeedback may serve as potent treatment approach for executive dysfunctions.

  14. Asymmetric function of theta and gamma activity in syllable processing: an intra-cortical study

    Directory of Open Access Journals (Sweden)

    Benjamin eMorillon

    2012-07-01

    Full Text Available Low-gamma (25-45 Hz and theta (4-8 Hz oscillations are proposed to underpin the integration of phonemic and syllabic information, respectively. How these two scales of analysis split functions across hemispheres is unclear. We analyzed cortical responses from an epileptic patient with a rare bilateral electrode implantation (stereotactic EEG in primary (A1/BA41 and A2/BA42 and association auditory cortices (BA22. Using time-frequency analyses, we confirmed the dominance of a 5-6 Hz theta activity in right and of a low-gamma (25-45 Hz activity in left primary auditory cortices (A1/A2, during both resting state and syllable processing. We further detected high-theta (7-8 Hz resting activity in left primary, but also associative auditory regions. In left BA22, its phase correlated with high-gamma induced power. Such a hierarchical relationship across theta and gamma frequency bands (theta/gamma phase-amplitude coupling could index the process by which the neural code shifts from stimulus feature- to phonological- encoding, and is associated with the transition from evoked to induced power responses. These data suggest that theta and gamma activity in right and left auditory cortices bear different functions. They support a scheme where slow parsing of the acoustic information dominates in right-hemisphere at a syllabic (5-6 Hz rate, and left auditory cortex exhibits a more complex cascade of oscillations, reflecting the possible extraction of transient acoustic cues at a fast (~25-45 Hz rate, subsequently integrated at a slower, e.g. syllabic one. Slow oscillations could functionally participate to speech processing by structuring gamma activity in left BA22, where abstract percepts emerge.

  15. Frontoparietal theta activity supports behavioral decisions in movement-target selection

    Directory of Open Access Journals (Sweden)

    Christian eRawle

    2012-05-01

    Full Text Available There is recent EEG evidence describing task-related changes of theta power in spatial attention and reaching/pointing tasks. Here, we aim to better characterize this theta activity and determine whether it is associated with visuospatial memory or with visuospatial selection functions of the frontoparietal cortex. We recorded EEG from 20 participants during a movement precuing task with centre-out joystick movements. Precues displayed 1, 2, or 4 potential targets and were followed (SOA 1.2 s by a central response cue indicating the movement target. Remembering the precued target location(s was mandatory in one and optional in a second version of the task. Analyses evaluated two slow brain potentials (CNV, contingent negative variation and CDA, contralateral delay activity and task-related power changes. Results showed a differential modulation of frontal CNV and parietal CDA, consistent with earlier described set-size effects on motor preparation and visual short-term memory. Short-lived phases of theta synchronization (ERS were found 150-500 ms after precue and response cue presentation, exhibiting parietal and frontal maxima. The increase of frontoparietal theta power following response cue presentation was strongly modulated by target load, i.e. absent for 1-target (when the movement target could be selected in advance, contrasting with a robust 20-50% ERS response in 2- and 4-target conditions. The scalp distribution, the timing, and the modulation by set-size suggest a role of theta activity in movement target selection. The results support a recently proposed view of theta as emerging around behavioral decision points, linked to the evaluation of choice-relevant information.

  16. Baryon resonances in the mean field approach and a simple explanation of the Theta+ pentaquark

    CERN Document Server

    Diakonov, Dmitri

    2008-01-01

    We suggest to classify baryon resonances as single-quark states in a mean field, and/or as its collective excitations. Identifying the Roper resonance N(1440), the nucleon resonance N(1535), and the singlet hyperon Lambda(1405) as single-quark excitations, we find that there must be an exotic S=+1 baryon resonance Theta+ (the "pentaquark") with a mass about 1440+1535-1405=1570 MeV and spin-parity one-half-plus. We argue that Theta+ is an analog of the Gamov--Teller excitation long known in nuclear physics.

  17. Transient loss of plasma from a theta pinch having an initially reversed magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, J. E.

    1981-01-01

    The results of an experimental study of the transient loss of plasma from a 25-cm-long theta pinch initially containing a reversed trapped magnetic field are presented. The plasma, amenable to MHD analyses, was a doubly ionized helium plasma characterized by an ion density N/sub i/ = 2 x 10/sup 16/ cm/sup -3/ and an ion temperature T/sub i/ = 15 eV at midcoil and by N/sub i/ = 0.5 x 10/sup 16/ cm/sup -3/ and T/sub i/ = 6 eV at a position 2.5 cm beyond the end of the theta coil.

  18. Study of the 2-d CP(N-1) models at \\theta=0 and \\pi

    CERN Document Server

    Beard, B B; Riederer, S; Wiese, U J

    2005-01-01

    We present numerical results for 2-d CP(N-1) models at \\theta=0 and \\pi obtained in the D-theory formulation. In this formulation we construct an efficient cluster algorithm and we show numerical evidence for a first order transition for CP(N-1\\geq 2) models at \\theta = \\pi. By a finite size scaling analysis, we also discuss the equivalence in the continuum limit of the D-theory formulation of the 2-d CP(N-1) models and the usual lattice definition.

  19. Sin/sup 2/theta/sub W/ and radiative corrections

    Energy Technology Data Exchange (ETDEWEB)

    Marciano, W.J.

    1986-01-01

    Precision measurements of sin/sup 2/theta/sub W/ and the effects of radiative corrections are surveyed. A world average sin/sup 2/theta/sub W/ = 0.229 +- 0.004 is obtained. Comparison of deep-inelastic ..nu../sub ..mu../N scattering and m/sub W/ or m/sub Z/ is shown to test the standard model at the quantum loop level and constrain new physics. Implications for grand unified theories are briefly discussed.

  20. Present status of the nonstrange and other flavor partners of the exotic Theta+ baryon

    CERN Document Server

    Strakovsky, I I; Azimov, Ya I; Polyakov, M V; Workman, R L; Azimov, Ya. I.

    2005-01-01

    Given the existing empirical information about the exotic Theta+ baryon, we analyze possible properties of its SU(3)F-partners, paying special attention to the nonstrange member of the antidecuplet N*. The modified piN partial-wave analysis presents two candidate masses, 1680 MeV and 1730 MeV. In both cases, the N* should be rather narrow and highly inelastic. Our results suggest several directions for experimental studies that may clarify properties of the antidecuplet baryons, and structure of their mixing with other baryons. Recent experimental evidence from the GRAAL and STAR Collaborations could be interpreted as observations of a candidate for the Theta+ nonstrange partner.

  1. Search for the pentaquark candidate $\\Theta^+$(1540) in the hyperon beam experiment WA89

    CERN Document Server

    Adamovich, M I; Baranov, S P; Barberis, D; Beck, M; Bérat, C; Beusch, W; Boss, M; Brons, S; Brückner, W; Buénerd, M; Busch, C; Büscher, C; Charignon, F; Chauvin, J; Chudakov, E A; Dersch, U; Dropmann, F; Engelfried, J; Faller, F; Fournier, A; Gerassimov, S G; Godbersen, M; Grafström, P; Haller, T; Heidrich, M; Hubbard, E; Hurst, R B; Königsmann, K C; Konorov, I; Keller, N; Martens, K; Martin, P; Masciocchi, S; Michaels, R; Müller, U; Neeb, H; Newbold, D; Newsom, C; Paul, S; Pochodzalla, J; Potashnikova, I; Povh, B; Ransome, R; Ren, Z; Epherre-Rey-Campagnolle, Marcelle; Rosner, G; Rossi, L; Rudolph, H; Scheel, C; Schmitt, L; Siebert,H W; Simon, A; Smith, V J; Thilmann, O; Trombini, A; Vesin, E; Volkemer, B; Vorwalter, K; Walcher, T; Wälder, G; Werding, R; Wittmann, E; Zavertyaev, M V

    2005-01-01

    We report on a high-statistics search for the \\t1540 resonance in $\\Sigma^-$-nucleus collisions at 340 \\gevc1 . No evidence for this resonance was found in our data sample which contains 13 millions $K^0_s \\to \\pi^+\\pi^- $ decays above background. For the decay channel $\\Theta^+ \\to K^0_s p$ and the kinematic range $x_F>$ 0.05 we find the production cross section to be $BR(\\Theta^+ \\to K^0_s p)\\cdot \\sigma_0 <$ 1.8 $\\mu$b per nucleon at 99% CL.

  2. Sight restoration after congenital blindness does not reinstate alpha oscillatory activity in humans.

    Science.gov (United States)

    Bottari, Davide; Troje, Nikolaus F; Ley, Pia; Hense, Marlene; Kekunnaya, Ramesh; Röder, Brigitte

    2016-01-01

    Functional brain development is characterized by sensitive periods during which experience must be available to allow for the full development of neural circuits and associated behavior. Yet, only few neural markers of sensitive period plasticity in humans are known. Here we employed electroencephalographic recordings in a unique sample of twelve humans who had been blind from birth and regained sight through cataract surgery between four months and 16 years of age. Two additional control groups were tested: a group of visually impaired individuals without a history of total congenital blindness and a group of typically sighted individuals. The EEG was recorded while participants performed a visual discrimination task involving intact and scrambled biological motion stimuli. Posterior alpha and theta oscillations were evaluated. The three groups showed indistinguishable behavioral performance and in all groups evoked theta activity varied with biological motion processing. By contrast, alpha oscillatory activity was significantly reduced only in individuals with a history of congenital cataracts. These data document on the one hand brain mechanisms of functional recovery (related to theta oscillations) and on the other hand, for the first time, a sensitive period for the development of alpha oscillatory activity in humans.

  3. Ab initio alpha-alpha scattering

    CERN Document Server

    Elhatisari, Serdar; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-01-01

    Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.

  4. Early expression of GABA(A) receptor delta subunit in the neonatal rat hippocampus.

    Science.gov (United States)

    Didelon, F; Mladinic', M; Cherubini, E; Bradbury, A

    2000-12-01

    The cDNA library screening strategy was used to identify the genes encoding for GABA(A) receptor subunits in the rat hippocampus during development. With this technique, genes encoding eleven GABA(A) receptor subunits were identified. The alpha5 subunit was by far the most highly expressed, followed by the gamma2, alpha2 and alpha4 subunits respectively. The expression of the beta2, alpha1, gamma1, beta1 and beta3 subunits was moderate, although that of the alpha3 and delta subunits was weak. In situ hybridization experiments, using digoxigenin-labeled cRNA probes, confirmed that the delta subunit was expressed in the neonatal as well as in the adult hippocampus, and is likely to form functional receptors in association with other subunits of the GABA(A) receptor. When the more sensitive RT-PCR approach was used, the gamma3 subunit was also detected, suggesting that this subunit is present in the hippocampus during development but at low levels of expression. The insertion of the delta subunit into functional GABA(A) receptors may enhance the efficacy of GABA in the immediate postnatal period when this amino acid is still exerting a depolarizing and excitatory action.

  5. Effects of a cognitive modulator in the theta and alpha asymmetry during a typewriting task: a sensorimotor integration perspective.

    Science.gov (United States)

    Cunha, Marlo; Machado, Sergio; Miana, Luiz Cláudio; Machado, Dionis; Bastos, Victor Hugo; Velasques, Bruna; Cagy, Maurício; Basile, Luis F; Piedade, Roberto; Ribeiro, Pedro

    2009-06-01

    This study aimed to elucidate cortical mechanisms and to identify the areas where occur such mechanisms due to interaction between bromazepam and motor learning. The sample was composed of 45 healthy subjects randomly distributed in 3 groups: placebo (n=15), bromazepam 3 mg (n=15) or bromazepam 6 mg (n=15). To perform the experimental task, subjects sat comfortably at a distance of approximately 20 cm from the typewriter. The typewriter keyboard was covered with a wooden box to avoid visual information about the hands' position. The typewriting task was performed concomitantly with EEG recording. ANOVA two-way results indicated a decreased asymmetry in sensorimotor areas in the experimental groups. Our interpretation is that moderate doses of bromazepam may improve performance on tasks with predictable elements to promote stability of psychomotor functions, but may also impair performance on tasks executed in unpredictable environments.

  6. Directed Communication between Nucleus Accumbens and Neocortex in Humans Is Differentially Supported by Synchronization in the Theta and Alpha Band

    NARCIS (Netherlands)

    Horschig, Jörn M; Smolders, Ruud; Bonnefond, Mathilde; Schoffelen, Jan-Mathijs; van den Munckhof, Pepijn; Schuurman, P Richard; Cools, Roshan; Denys, D.; Jensen, Ole

    2015-01-01

    Here, we report evidence for oscillatory bi-directional interactions between the nucleus accumbens and the neocortex in humans. Six patients performed a demanding covert visual attention task while we simultaneously recorded brain activity from deep-brain electrodes implanted in the nucleus accumben

  7. Determination of absorbed dose in water at the reference point D(r{sub 0},{theta}{sub 0}) for an {sup 192}Ir HDR brachytherapy source using a Fricke system

    Energy Technology Data Exchange (ETDEWEB)

    Austerlitz, C.; Mota, H. C.; Sempau, J.; Benhabib, S. M.; Campos, D.; Allison, R.; Almeida, C. E. de; Zhu, D.; Sibata, C. H. [Department of Radiation Oncology, East Carolina University, Greenville, North Carolina 27834 (United States); Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, 08028 Barcelona (Spain); Department of Radiation Oncology, East Carolina University, Greenville, North Carolina 27834 (United States); Laboratorio de Cie circumflex ncias Radiologicas, Universidade do Estado do Rio de Janeiro, 20550 Rio de Janeiro (Brazil); Department of Radiation Oncology, East Carolina University, Greenville, North Carolina 27834 (United States)

    2008-12-15

    A ring-shaped Fricke device was developed to measure the absolute dose on the transverse bisector of a {sup 192}Ir high dose rate (HDR) source at 1 cm from its center in water, D(r{sub 0},{theta}{sub 0}). It consists of a polymethylmethacrylate (PMMA) rod (axial axis) with a cylindrical cavity at its center to insert the {sup 192}Ir radioactive source. A ring cavity around the source with 1.5 mm thickness and 5 mm height is centered at 1 cm from the central axis of the source. This ring cavity is etched in a disk shaped base with 2.65 cm diameter and 0.90 cm thickness. The cavity has a wall around it 0.25 cm thick. This ring is filled with Fricke solution, sealed, and the whole assembly is immersed in water during irradiations. The device takes advantage of the cylindrical geometry to measure D(r{sub 0},{theta}{sub 0}). Irradiations were performed with a Nucletron microselectron HDR unit loaded with an {sup 192}Ir Alpha Omega radioactive source. A Spectronic 1001 spectrophotometer was used to measure the optical absorbance using a 1 mL quartz cuvette with 1.00 cm light pathlength. The PENELOPE Monte Carlo code (MC) was utilized to simulate the Fricke device and the {sup 192}Ir Alpha Omega source in detail to calculate the perturbation introduced by the PMMA material. A NIST traceable calibrated well type ionization chamber was used to determine the air-kerma strength, and a published dose-rate constant was used to determine the dose rate at the reference point. The time to deliver 30.00 Gy to the reference point was calculated. This absorbed dose was then compared to the absorbed dose measured by the Fricke solution. Based on MC simulation, the PMMA of the Fricke device increases the D(r{sub 0},{theta}{sub 0}) by 2.0%. Applying the corresponding correction factor, the D(r{sub 0},{theta}{sub 0}) value assessed with the Fricke device agrees within 2.0% with the expected value with a total combined uncertainty of 3.43%(k=1). The Fricke device provides a promising

  8. The structure of the blue luminescent delta-phase of tris(8-hydroxyquinoline)aluminium(III) (Alq3).

    Science.gov (United States)

    Cölle, Michael; Dinnebier, Robert E; Brütting, Wolfgang

    2002-12-07

    The existence of the facial isomer in the delta-phase of Alq3 is proven by X-ray structural analysis, revealing that both the different molecular structure and the weaker overlap of the pi-orbitals of hydroxyquinoline ligands belonging to neighboring Alq3 molecules as compared to other phases (alpha, beta) are likely to be the origin of the significantly different optical properties of delta-Alq3.

  9. Student Difficulties with the Dirac Delta Function

    CERN Document Server

    Wilcox, Bethany R

    2014-01-01

    The Dirac delta function is a standard mathematical tool used in multiple topical areas in the undergraduate physics curriculum. While Dirac delta functions are usually introduced in order to simplify a problem mathematically, students often struggle to manipulate and interpret them. To better understand student difficulties with the delta function at the upper-division level, we examined responses to traditional exam questions and conducted think-aloud interviews. Our analysis was guided by an analytical framework that focuses on how students activate, construct, execute, and reflect on the Dirac delta function in physics. Here, we focus on student difficulties using the delta function to express charge distributions in the context of junior-level electrostatics. Challenges included: invoking the delta function spontaneously, constructing two- and three-dimensional delta functions, integrating novel delta function expressions, and recognizing that the delta function can have units.

  10. Study of CP(N-1) \\theta-Vacua by Cluster-Simulation of SU(N) Quantum Spin Ladders

    CERN Document Server

    Beard, B B; Riederer, S; Wiese, U J

    2005-01-01

    D-theory provides an alternative lattice regularization of the (1+1)-d CP(N-1) quantum field theory. In this formulation the continuous classical CP(N-1) fields emerge from the dimensional reduction of discrete SU(N) quantum spins. In analogy to Haldane's conjecture, ladders consisting of an even number of transversely coupled spin chains lead to a CP(N-1) model with vacuum angle \\theta = 0, while an odd number of chains yields \\theta = \\pi. In contrast to Wilson's formulation of lattice field theory, in D-theory no sign problem arises at \\theta = \\pi, and an efficient cluster algorithm is used to investigate the \\theta-vacuum effects. At \\theta = \\pi there is a first order phase transition with spontaneous breaking of charge conjugation symmetry for CP(N-1) models with N>2.

  11. Obtaining nonvanishing $\\theta_{13}$ with constrained neutrino Yukawa matrix and implications for flavor model buildings

    CERN Document Server

    Zhao, Ya

    2016-01-01

    Assuming a diagonal Majorana neutrino mass matrix, we investigate the neutrino Yukawa textures which lead to a non-zero reactor mixing angle $\\theta_{13}$. The neutrino effective coupling matrix $\\kappa^{eff}$ is pre-diagonalized by a constant mixing pattern $V_{\

  12. White paper report on using nuclear reactors to search for a value of theta13

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, K.; Anjos, J.C.; Ayres, D.; Beacom, J.; Bediaga, I.; de Bellefon, A.; Berger, B.E.; Bilenky, S.; Blucher, E.; Bolton, T.; Buck, C.; Bugg, W.; Busenitz, J.; Choubey, S.; Conrad, J.; Cribier, M.; Dadoun, O.; Dalnoki-Veress, F.; Decowski, M.; de Gouvea, Andre; Demutrh, D.; Dessages-Ardellier, F.; Efremenko, Y.; von Feilitzsch, F.; Finley, D.; Formaggio, J.A.; Freedman, S.J.; Fujikawa, B.K.; Garbini, M.; Giusti, P.; Goger-Neff, M.; Goodman, M.; Gray, F.; Grieb, C.; Grudzinski, J.J.; Guarino, V.J.; Hartmann, F.; Hagner, C.; Heeger, K.M.; Hofmann, W.; Horton-Smith, G.; Huber, P.; Inzhechik, L.; Jochum, J.; Jostlein, H.; Kadel, R.; Kamyshkov, Y.; Kaplan, D.; Kasper, P.; de Kerret, H.; Kersten, J.; Klein, J.; Knopfle, K.T.; Kopeikin, V.; Kozlov, Yu.; Kryn, D.; Kuchler, V.; Kuze, M.; Lachenmaier, T.; Lasserre, T.; Laughton, C.; Lendvai, C.; Li, J.; Lindner, M.; Link, J.; Longo, M.; Lu, Y.S.; Luk, K.B.; Ma, Y.Q.; Martemyanov, V.P.; Mauger, C.; Manghetti, H.; McKeown, R.; Mention, G.; Meyer, J.P.; Mikaelyan, L.; Minakata, H.; Naples, D.; Nunokawa, H.; Oberauer, L.; Obolensky, M.; Parke, S.; Petcov, S.T.; Peres, O.L.G.; Potzel, W.; Pilcher, J.; Plunkett, R.; Raffelt, G.; Rapidis, P.; Reyna, D.; Roe, B.; Rolinec, M.; Sakamoto, Y.; Sartorelli, G.; Schonert, S.; Schwertz, T.; Selvi, M.; Shaevitz, M.; Shellard, R.; Shrock, R.; Sidwell, R.; Sims, J.; Sinev, V.; Stanton, N.; Stancu, I.; Stefanski, R.; Seukane, F.; Sugiyama, H.; Sukhotin, S.; Sumiyoshi, T.; Svoboda, R.; Talaga, R.; Tamura, N.; Tanimoto, M.; Thron, J.; von Toerne, E.; Vignaud, D.; Wagner, C.; Wang, Y.F.; Wang, Z.; Winter, W.; Wong, H.; Yakushev, E.; Yang, C.G.; Yasuda, O.

    2004-02-26

    There has been superb progress in understanding the neutrino sector of elementary particle physics in the past few years. It is now widely recognized that the possibility exists for a rich program of measuring CP violation and matter effects in future accelerator {nu} experiments, which has led to intense efforts to consider new programs at neutrino superbeams, off-axis detectors, neutrino factories and beta beams. However, the possibility of measuring CP violation can be fulfilled only if the value of the neutrino mixing parameter {theta}{sub 13} is such that sin{sup 2} (2{theta}{sub 13}) greater than or equal to on the order of 0.01. The authors of this white paper are an International Working Group of physicists who believe that a timely new experiment at a nuclear reactor sensitive to the neutrino mixing parameter {theta}{sub 13} in this range has a great opportunity for an exciting discovery, a non-zero value to {theta}{sub 13}. This would be a compelling next step of this program. We are studying possible new reactor experiments at a variety of sites around the world, and we have collaborated to prepare this document to advocate this idea and describe some of the issues that are involved.

  13. Coherent theta oscillations and reorganization of spike timing in the hippocampal-prefrontal network upon learning

    NARCIS (Netherlands)

    Benchenane, K.; Peyrache, A.; Khamassi, M.; Tierney, P.L.; Gioanni, Y.; Battaglia, F.P.; Wiener, S.I.

    2010-01-01

    To study the interplay between hippocampus and medial prefrontal cortex (Pfc) and its importance for learning and memory consolidation, we measured the coherence in theta oscillations between these two structures in rats learning new rules on a Y maze. Coherence peaked at the choice point, most stro

  14. Effective pathfinding for four-wheeled robot based on combining Theta* and hybrid A* algorithms

    Directory of Open Access Journals (Sweden)

    Віталій Геннадійович Михалько

    2016-07-01

    Full Text Available Effective pathfinding algorithm based on Theta* and Hybrid A* algorithms was developed for four-wheeled robot. Pseudocode for algorithm was showed and explained. Algorithm and simulator for four-wheeled robot were implemented using Java programming language. Algorithm was tested on U-obstacles, complex maps and for parking problem

  15. Aging affects medial but not anterior frontal learning-related theta oscillations.

    Science.gov (United States)

    van de Vijver, Irene; Cohen, Michael X; Ridderinkhof, K Richard

    2014-03-01

    Aging induces a decline in the ties that bind anatomical networks centered on the prefrontal cortex, which are critical for reinforcement learning and decision making. At the neurophysiological level, the prefrontal cortex may engage electrophysiological oscillatory synchronization to coordinate other brain systems during learning. We recorded scalp EEG from 21 older (mean age 69 years) and 20 young (mean age 22 years) healthy human adults while they learned stimulus-response mappings by trial-and-error using feedback. In young adults, theta-band (4-8 Hz) oscillatory power over medial frontal and anterior frontal cortex predicted learning after errors. Older adults demonstrated a decrease in the theta-band learning-predictive signals over medial frontal but not anterior frontal cortex. This age-related decrease in task-relevant medial frontal theta power may be related to the more general decrease in medial frontal theta power that we observed during rest. These results demonstrate a shift in cortical networks that support reinforcement learning in older adults, and shed new light on the changes in neurophysiological (oscillatory) mechanisms with neurocognitive aging. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Chromosomal localization of the gene for the human Theta class glutathione transferase (GSTT1)

    Energy Technology Data Exchange (ETDEWEB)

    Webb, G.; Vaska, V. [Queen Elizabeth Hospital, Adelaide (Australia); Goggan, M.; Board, P. [Australian National Univ., Canberra (Australia)

    1996-04-01

    Two loci encoding Theta class glutathione transferases (GSTs) have been identified in humans. In situ hybridization studies have localized the GSTT1 gene to 22q11.2. This is the same band to which we previously localized the GSTT2 gene. This finding confirms the trend for human GST genes to be found in class-specific clusters. 20 refs., 1 fig.

  17. Seasonal variation of Sigma sub(Theta) with wind speed, direction and stability

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    For an airport site near Visakhapatnam, India, and based on 10 years of data for the months of January, April, August and October, values of Sigma sub(Theta) are given as a function of wind speed, wind direction and Pasquill diffusion category...

  18. Changes in absolute theta power in bipolar patients during a saccadic attention task.

    Science.gov (United States)

    Cartier, Consuelo; Diniz, Claudia; Di Girogio, Luiza; Bittencourt, Juliana; Gongora, Mariana; Ken Tanaka, Guaraci; Teixeira, Silmar; Basile, Luis F; Novis, Fernanda; Angélica Silveira, Luciana; da Silva, Rafael de Assis; Cagy, Mauricio; Cheniaux, Elie; Ribeiro, Pedro; Velasques, Bruna

    2015-08-30

    The present study analyzed absolute theta power (ATP) in brain areas involved with attention in the three phase of BD while the patients performing a saccadic attention task. We hypothesized that patients in depression and mania states show a higher ATP compared to euthymic patients, since a higher ATP is indicative of attention deficit. We analyzed the frontal (F7, F3, Fz, F4 and F8) and central (C3, Cz and C4) areas. Thirty bipolar patients were enrolled in this study. The subjects performed a saccadic attention task while their brain activity pattern was recorded using quantitative electroencephalography (20 channels). Our results showed a main effect for group over C3, C4, Cz, F7, F4, F8 electrodes, and a main effect for moment over Cz, F7, F8 electrodes. These results indicate that both task and groups produce changes in theta activity in distinct cortical areas that participate in the organization of attention. Our results therefore demonstrate that, although it is well established in the literature that theta has a relevant role in the attention process, it is necessary to deepen the investigations to better understand the specifics of theta during visual processing tasks that have a demand for attention.

  19. The Psychological Reality of Grammar : the Theta Principle in Parsing Performance

    NARCIS (Netherlands)

    Sadeh-Leicht, O.

    2007-01-01

    This dissertation presents evidence for the psychological reality of a grammatical principle, the Theta Principle. It adopts a grammar-derived theory of human natural language processing ? the thematic parser. Parsing phenomena such as garden path effects (The horse raced past the barn fell) and cen

  20. Periods of hyperelliptic integrals expressed in terms of theta-constants by means of Thomae formulae.

    Science.gov (United States)

    Enolski, Victor; Richter, Peter

    2008-03-28

    Expressions for the periods of first- and second-kind integrals on hyperelliptic curves are given in terms of theta-constants. They are derived with the help of Thomae's classical formulae and Picard-Fuchs equations for complete integrals as functions of the parameters of the curves. The example of genus 2 is considered in detail.

  1. Continuous Theta-Burst Stimulation Demonstrates a Causal Role of Premotor Homunculus in Action Understanding

    DEFF Research Database (Denmark)

    Michael, John; Sandberg, Kristian; Skewes, Joshua

    2014-01-01

    Although it is well established that regions of premotor cortex (PMC) are active during action observation, it remains controversial whether they play a causal role in action understanding. In the experiment reported here, we used offline continuous theta-burst stimulation (cTBS) to investigate...

  2. The theta parameter in loop quantum gravity: effects on quantum geometry and black hole entropy

    CERN Document Server

    Rezende, Danilo Jimenez

    2007-01-01

    The precise analog of the theta-quantization ambiguity of Yang-Mills theory exists for the real SU(2) connection formulation of general relativity. As in the former case theta labels representations of large gauge transformations, which are super-selection sectors in loop quantum gravity. We show that unless theta=0, the (kinematical) geometric operators such as area and volume are not well defined on spin network states. More precisely the intersection of their domain with the dense set Cyl in the kinematical Hilbert space H of loop quantum gravity is empty. The absence of a well defined notion of area operator acting on spin network states seems at first in conflict with the expected finite black hole entropy. However, we show that the black hole (isolated) horizon area--which in contrast to kinematical area is a (Dirac) physical observable--is indeed well defined, and quantized so that the black hole entropy is proportional to the area. The effect of theta is negligible in the semiclassical limit where pro...

  3. Lepton mixing angle $\\theta_{13} = 0$ with a horizontal symmetry $D_4$

    CERN Document Server

    Grimus, Walter; Kaneko, S; Lavoura, L; Tanimoto, M

    2004-01-01

    We discuss a model for the lepton sector based on the seesaw mechanism and on a $D_4$ family symmetry. The model predicts the mixing angle $\\theta_{13}$ to vanish. The solar mixing angle $\\theta_{12}$ is free--it will in general be large if one does not invoke finetuning. The model has an enlarged scalar sector with three Higgs doublets, together with two real scalar gauge singlets $\\chi_i$ ($ i = 1, 2$) which have vacuum expectation values _0$ at the seesaw scale. The atmospheric mixing angle $\\theta_{23}$ is given by $\\tan \\theta_{23} = _0$ /_0$, and it is maximal if the Lagrangian is $D_4$-invariant; but $D_4$ may be broken softly, by a term of dimension two in the scalar potential, and then m_2 > m_1$) and allows successful leptogenesis if $m_1 \\sim 4 \\times 10^{-3} \\mathrm{eV}$; these properties of the model are independent of the presence and strength of the soft $D_4$ breaking.

  4. Continuous Theta-Burst Stimulation Demonstrates a Causal Role of Premotor Homunculus in Action Understanding

    DEFF Research Database (Denmark)

    Michael, John; Sandberg, Kristian; Skewes, Joshua

    2014-01-01

    Although it is well established that regions of premotor cortex (PMC) are active during action observation, it remains controversial whether they play a causal role in action understanding. In the experiment reported here, we used offline continuous theta-burst stimulation (cTBS) to investigate t...

  5. The radii and limb darkenings of Alpha Centauri A and B - Interferometric measurements with VLTI/PIONIER

    CERN Document Server

    Kervella, P; Gallenne, A; Thévenin, F

    2016-01-01

    The photospheric radius is one of the fundamental parameters governing the radiative equilibrium of a star. We report new observations of the nearest solar-type stars Alpha Centauri A (G2V) and B (K1V) with the VLTI/PIONIER optical interferometer. The combination of four configurations of the VLTI enable us to measure simultaneously the limb darkened angular diameter thetaLD and the limb darkening parameters of the two solar-type stars in the near-infrared H band (lambda = 1.65 microns). We obtain photospheric angular diameters of thetaLD(A) = 8.502 +/- 0.038 mas (0.43%) and thetaLD(B) = 5.999 +/- 0.025 mas (0.42%), through the adjustment of a power law limb darkening model. We find H band power law exponents of alpha(A) = 0.1404 +/- 0.0050 (3.6%) and alpha(B) = 0.1545 +/- 0.0044 (2.8%), which closely bracket the observed solar value (alpha_sun = 0.15027). Combined with the parallax pi = 747.17 +/- 0.61 mas recently determined, we derive linear radii of RA = 1.2234 +/- 0.0053 Rsun (0.43%) and RB = 0.8632 +/- ...

  6. Exploiting non-constant safe memory in resilient algorithms and data structures

    DEFF Research Database (Denmark)

    De Stefani, Lorenzo; Silvestri, Francesco

    2015-01-01

    We extend the Faulty RAM model by Finocchi and Italiano (2008) by adding a safe memory of arbitrary size $S$, and we then derive tradeoffs between the performance of resilient algorithmic techniques and the size of the safe memory. Let $\\delta$ and $\\alpha$ denote, respectively, the maximum amount...... of faults which can happen during the execution of an algorithm and the actual number of occurred faults, with $\\alpha \\leq \\delta$. We propose a resilient algorithm for sorting $n$ entries which requires $O\\left(n\\log n+\\alpha (\\delta/S + \\log S)\\right)$ time and uses $\\Theta(S)$ safe memory words. Our...... algorithm outperforms previous resilient sorting algorithms which do not exploit the available safe memory and require $O\\left(n\\log n+ \\alpha\\delta\\right)$ time. Finally, we exploit our sorting algorithm for deriving a resilient priority queue. Our implementation uses $\\Theta(S)$ safe memory words...

  7. Learning to learn: theta oscillations predict new learning, which enhances related learning and neurogenesis.

    Directory of Open Access Journals (Sweden)

    Miriam S Nokia

    Full Text Available Animals in the natural world continuously encounter learning experiences of varying degrees of novelty. New neurons in the hippocampus are especially responsive to learning associations between novel events and more cells survive if a novel and challenging task is learned. One might wonder whether new neurons would be rescued from death upon each new learning experience or whether there is an internal control system that limits the number of cells that are retained as a function of learning. In this experiment, it was hypothesized that learning a task that was similar in content to one already learned previously would not increase cell survival. We further hypothesized that in situations in which the cells are rescued hippocampal theta oscillations (3-12 Hz would be involved and perhaps necessary for increasing cell survival. Both hypotheses were disproved. Adult male Sprague-Dawley rats were trained on two similar hippocampus-dependent tasks, trace and very-long delay eyeblink conditioning, while recording hippocampal local-field potentials. Cells that were generated after training on the first task were labeled with bromodeoxyuridine and quantified after training on both tasks had ceased. Spontaneous theta activity predicted performance on the first task and the conditioned stimulus induced a theta-band response early in learning the first task. As expected, performance on the first task correlated with performance on the second task. However, theta activity did not increase during training on the second task, even though more cells were present in animals that had learned. Therefore, as long as learning occurs, relatively small changes in the environment are sufficient to increase the number of surviving neurons in the adult hippocampus and they can do so in the absence of an increase in theta activity. In conclusion, these data argue against an upper limit on the number of neurons that can be rescued from death by learning.

  8. Selective theta-synchronization of choice-relevant information subserves goal-directed behavior

    Directory of Open Access Journals (Sweden)

    Thilo eWomelsdorf

    2010-11-01

    Full Text Available Theta activity reflects a state of rhythmic modulation of excitability at the level of single neuron membranes, within local neuronal groups and between distant nodes of a neuronal network. A wealth of evidence has shown that during theta states distant neuronal groups synchronize, forming networks of spatially confined neuronal clusters at specific time periods during task performance. Here, we show that a functional commonality of networks engaging in theta rhythmic states is that they emerge around decision points, reflecting rhythmic synchronization of choice-relevant information. Decision points characterize a point in time shortly before a subject chooses to select one action over another, i.e. when automatic behavior is terminated and the organism reactivates multiple sources of information to evaluate the evidence for available choices. As such, decision processes require the coordinated retrieval of choice-relevant information including (i the retrieval of stimulus evaluations (stim.-reward associations and reward expectancies about future outcomes, (ii the retrieval of past and prospective memories (e.g. stim.-stim. associations, (iii the reactivation of contextual task rule representations (e.g. stim.-response mappings, along with (iv an ongoing assessment of sensory evidence. An increasing number of studies reveal that retrieval of these multiple types of information proceeds within few theta cycles through synchronized spiking activity across limbic, striatal and cortical processing nodes. The outlined evidence suggests that evolving spatially and temporally specific theta synchronization could serve as the critical correlate underlying the selection of a choice during goal-directed behavior.

  9. Stress affects theta activity in limbic networks and impairs novelty-induced exploration and familiarization

    Directory of Open Access Journals (Sweden)

    Luis eJacinto

    2013-10-01

    Full Text Available Exposure to a novel environment triggers the response of several brain areas that regulate emotional behaviors. Here, we studied theta oscillations within the hippocampus (HPC-amygdala (AMY-medial prefrontal cortex (mPFC network in exploration of a novel environment and subsequent familiarization through repeated exposures to that same environment; in addition, we assessed how concomitant stress exposure could disrupt this activity and impair both behavioral processes. Local field potentials were simultaneously recorded from dorsal and ventral hippocampus (dHPC and vHPC respectively, basolateral amygdala (BLA and mPFC in freely behaving rats while they were exposed to a novel environment, then repeatedly re-exposed over the course of 3 weeks to that same environment and, finally, on re-exposure to a novel unfamiliar environment. A longitudinal analysis of theta activity within this circuit revealed a reduction of vHPC and BLA theta power and vHPC-BLA theta coherence through familiarization which was correlated with a return to normal exploratory behavior in control rats. In contrast, a persistent over-activation of the same brain regions was observed in stressed rats that displayed impairments in novel exploration and familiarization processes. Importantly, we show that stress also affected intra-hippocampal synchrony and heightened the coherence between vHPC and BLA. In summary, we demonstrate that modulatory theta activity in the aforementioned circuit, namely in the vHPC and BLA, is correlated with the expression of anxiety in novelty-induced exploration and familiarization in both normal and pathological conditions.

  10. Simultaneous activation of gamma and theta network oscillations in rat hippocampal slice cultures.

    Science.gov (United States)

    Fischer, Yacov; Wittner, Lucia; Freund, Tamas F; Gähwiler, Beat H

    2002-03-15

    Hippocampal activity in vivo is characterized by concurrent oscillations at theta (4-15 Hz) and gamma (20-80 Hz) frequencies. Here we show that cholinergic receptor activation (methacholine 10-20 nm) in hippocampal slice cultures induces an oscillatory mode of activity, in which the intrinsic network oscillator (located in the CA3 area) expresses simultaneous theta and gamma network oscillations. Pyramidal cells display synaptic theta oscillations, characterized by cycles consisting of population EPSP-IPSP sequences that are dominated by population IPSPs. These rhythmic IPSPs most probably result from theta-modulated spiking activity of several interneurons. At the same time, the majority of interneurons consistently display synaptic gamma oscillations. These oscillatory cycles consist of fast depolarizing rhythmic events that are likely to reflect excitatory input from CA3 pyramidal cells. Interneurons comprising this functional group were identified morphologically. They include four known types of interneurons (basket, O-LM, bistratified and str. lucidum-specific cells) and one new type of CA3 interneuron (multi-subfield cell). The oscillatory activity of these interneurons is only weakly correlated between neighbouring cells, and in about half of these (44 %) is modulated by depolarizing theta rhythmicity. The overall characteristics of acetylcholine-induced oscillations in slice cultures closely resemble the rhythmicity observed in hippocampal field and single cell recordings in vivo. Both rhythmicities depend on intrinsic synaptic interactions, and are expressed by different cell types. The fact that these oscillations persist in a network lacking extra-hippocampal connections emphasizes the importance of intrinsic mechanisms in determining this form of hippocampal activity.

  11. Nicotine induction of theta frequency oscillations in rodent medial septal diagonal band in vitro

    Institute of Scientific and Technical Information of China (English)

    Cheng-biao LU; Cheng-zhang LI; Dong-liang LI; Zaineb HENDERSON

    2013-01-01

    Aim:This study aimed to examine the role of the nicotinic receptor (nAChR) in the generation of theta oscillations (4-12 Hz) in vitro.Methods:Electrophysiological studies were performed on medial septal diagonal band area (MSDB) slices to measure theta oscillation.Immunofluorescence and confocal microscopy studies were carried out to detect α4 nAChR and β2 nAChR subunits in perfused-fixed tissue from VGluT2-GFP and GAD67-GFP transgenic mice.Results:Application of nicotine to MSDB slices produced persistent theta oscillations in which area power increased in a doseresponsive manner.This activity was inhibited by GABAA receptor antagonists and partially by ionotropic glutamate receptor antagonists,indicating the involvement of local GABAergic and glutamatergic neurons in the production of the rhythmic activity.The nicotineinduced theta activity was also inhibited selectively by non-α7*nAChR antagonists,suggesting the presence of these receptor types on GABAergic and glutamatergic neuron populatjons in the MSDB.This was confirmed by immunofluorescence and confocal microscopy studies in transgenic mice in which the GABAergic and glutamatergic neurons express green fluorescent protein (GFP),showing Iocalisation of β2 nAChR and α4 nAChR subunits,the most common constituents of non-α7*nAChRs,in both cell types in the MSDB.Conclusion:Theta activity in the MSDB may be generated by tonic stimulation of non-α7*nAChRs.

  12. Faddeev calculation of 3 alpha and alpha alpha Lambda systems using alpha alpha resonating-group method kernel

    CERN Document Server

    Fujiwara, Y; Kohno, M; Suzuki, Y; Baye, D; Sparenberg, J M

    2004-01-01

    We carry out Faddeev calculations of three-alpha (3 alpha) and two-alpha plus Lambda (alpha alpha Lambda) systems, using two-cluster resonating-group method kernels. The input includes an effective two-nucleon force for the alpha alpha resonating-group method and a new effective Lambda N force for the Lambda alpha interaction. The latter force is a simple two-range Gaussian potential for each spin-singlet and triplet state, generated from the phase-shift behavior of the quark-model hyperon-nucleon interaction, fss2, by using an inversion method based on supersymmetric quantum mechanics. Owing to the exact treatment of the Pauli-forbidden states between the clusters, the present three-cluster Faddeev formalism can describe the mutually related, alpha alpha, 3 alpha and alpha alpha Lambda systems, in terms of a unique set of the baryon-baryon interactions. For the three-range Minnesota force which describes the alpha alpha phase shifts quite accurately, the ground-state and excitation energies of 9Be Lambda are...

  13. {Delta}I = 3/2 and {Delta}S = 2 Hyperon decays in chiral perturbation theory

    Energy Technology Data Exchange (ETDEWEB)

    He, X.G. [University of Melbourne, Parkville, VIC (Australia). School of Physics; Valencia, G. [Iowa State University, Ames, Iowa (United States). Department of Physics and Astronomy

    1997-05-01

    We study the| {Delta}I| = 3/2 and |{Delta}S| = 2 amplitudes for hyperon decays of the form B {yields} B`{pi} at lowest order in chiral perturbation theory. At this order, the {Delta}I = 3/2 amplitudes depend on only one constant. We extract the value of this constant from experiment and find a reasonable description of these processes within experimental errors. The same constant determines the {Delta}S = 2 transitions which, in the standard model, are too small to be observed. We find that new physics with parity odd {Delta}S = 2 interactions can produce observable rates in hyperon decays while evading the bounds from K{sup 0} - K-bar{sup 0} mixing. (authors) 10 refs., 3 tabs.

  14. Alpha Thalassemia (For Parents)

    Science.gov (United States)

    ... Kids to Be Smart About Social Media Alpha Thalassemia KidsHealth > For Parents > Alpha Thalassemia Print A A ... Complications Symptoms Diagnosis Treatment en español Alfa talasemia Thalassemias Thalassemias are a group of blood disorders that ...

  15. Reactive versus anticipative adaptive management of Deltas: The Sacramento-San Joaquin Delta and the Rhine-Meuse Delta compared

    NARCIS (Netherlands)

    Vlieg, T.J.; Zandvoort, M.

    2013-01-01

    In this paper Californian Adaptive Management (AM) and Dutch Adaptive Delta Management (ADM) are compared. The concepts are introduced in a policy context to deal with prevailing types of uncertainty in water management in the Californian Sacramento-San Joaquin Delta and the Dutch Rhine-Meuse Delta

  16. Effects of alpha-tocopherol on lactones in beef headspace during storage.

    Science.gov (United States)

    Watanabe, A; Imanari, M; Higuchi, M; Shiba, N; Yonai, M

    2010-01-01

    We studied the effect of alpha-tocopherol (alpha-Toc) on the production of lactones, a desirable flavor in Wagyu beef (Japanese Black Cattle), in meat headspace. Fresh beef was minced and divided into 4 groups containing different alpha-Toc levels (1.9, 2.7, 6.1, and 10.7 mg/kg) or packed with oxygen absorber. After 10 d of storage at 2 °C, these samples were cooked in distilled water and rendered fat was collected. The headspace of the fat was analyzed with solid-phase microextraction combined with gas chromatography-mass spectrometry. The DB-17MS capillary column led to good separation of aliphatic lactones. Oxygen was important for the development of all lactones during storage. The amounts of gamma-octalactone and gamma-nonalactone decreased linearly with increasing alpha-Toc levels. The effect of alpha-Toc on delta-decalactone, delta-undecalactone, and delta-tetoradecalactone was weaker, and that on delta-hexadecalactone was ambiguous. These observations suggest that oxidation was necessary to develop the flavor of Wagyu beef, and warn that an excessive increase of alpha-Toc could reduce levels of positive flavor components, gamma-octalactone and gamma-nonalactone, in the headspace of Wagyu beef. © 2010 Institute of Food Technologists®

  17. Facts About Delta Pi Epsilon

    Science.gov (United States)

    Delta Pi Epsilon Journal, 1976

    1976-01-01

    The article discusses the purpose and structure of Delta Pi Epsilon and the general qualifications for membership. Service projects and publications, research awards, timely facts, the year of each chapter's origination, national presidents, and executive secretaries for the last 40 years are listed. (BP)

  18. The Alpha Antihydrogen Experiment

    Science.gov (United States)

    Madsen, N.; Andresen, G.; Bertsche, W.; Boston, A.; Bowe, P. D.; Butler, E.; Cesar, C. L.; Chapman, S.; Charlton, M.; Chartier, M.; Fajans, J.; Funakoshi, R.; Gill, D. R.; Hangst, J. S.; Hardy, W. N.; Hayano, R. S.; Hayden, M.; Hydomako, R.; Jenkins, M. J.; Jørgensen, L. V.; Kurchaninov, L.; Nolan, P.; Olchanski, K.; Olin, A.; Page, R. D.; Povilus, A.; Robicheaux, F.; Sarid, E.; Seif El Nasr, S.; Silveira, D. M.; Storey, J. W.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.; Yamazaki, Y.

    2008-03-01

    ALPHA is a new experiment at the CERN Antiproton Decelerator (AD). The short term goal of ALPHA is trapping of cold antihydrogen, with the long term goal of conducting precise spectroscopic comparisons of hydrogen and antihydrogen. Here we present the current status of ALPHA and the physics considerations and results leading to its design as well as recent progress towards trapping.

  19. RBE estimation of proton radiation fields using a DeltaE-E telescope.

    Science.gov (United States)

    Wroe, Andrew; Schulte, Reinhard; Fazzi, Alberto; Pola, Andrea; Agosteo, Stefano; Rosenfeld, Anatoly

    2009-10-01

    A new monolithic silicon DeltaE-E telescope was evaluated in unmodulated and modulated 100 MeV proton beams used for hadron therapy. Compared to a classical microdosimetry detector, which provides one-dimensional information on lineal energy of charged particles, this detector system provides two-dimensional information on lineal energy and particle energy based on energy depositions, collected in coincidence, within the DeltaE and E stages of the detector. The authors investigated the possibility to use the information obtained with the DeltaE-E telescope to determine the relative biological effectiveness (RBE) at defined locations within the proton Bragg peak and spread-out Bragg peak (SOBP). An RBE matrix based on the established in vitro V79 cell survival data was developed to link the output of the device directly to RBE(alpha), the RBE in the low-dose limit, at various depths in a homogeneous polystyrene phantom. In the SOBP of a 100 MeV proton beam, the RBE(alpha) increased from 4.04 proximal to the SOBP to a maximum value of 5.4 at the distal edge. The DeltaE-E telescope, with its high spatial resolution, has potential applications to biologically weighted hadron treatment planning as it provides a compact and portable means for estimating the RBE in rapidly changing hadron radiation fields within phantoms.

  20. Hydrological and Climatic Significance of Martian Deltas

    Science.gov (United States)

    Di Achille, G.; Vaz, D. A.

    2017-10-01

    We a) review the geomorphology, sedimentology, and mineralogy of the martian deltas record and b) present the results of a quantitative study of the hydrology and sedimentology of martian deltas using modified version of terrestrial model Sedflux.