Detecting bilateral motor associated areas with resting state functional magnetic resonance: the effect of different seed points selection on the results

International Nuclear Information System (INIS)

Yi Huiming; Yang Mingming; Meng Liangliang; Zhang Jing

2011-01-01

Objective: To investigate the effect of different seed points selection on localizing bilateral hand motor associated areas in resting state functional magnetic resonance. Methods: Thirty -one subjects were recruited (male 15, female 16), all of them underwent both block-designed fMRI scan during performing bilateral hand motor task and resting-state fMRI scan. DPARSA V2.0 and SPM8 were used to process the data. The peak voxels in the activity map of the task scan were selected as seeds to compute functional connectivity map of the resting-state scan. Spatial correlation analysis was performed to compare the activity map of the task scan and the connectivity map of the resting- state scan. Results: Fifteen isolated clusters were picked to generate the peak voxels, which were selected as seeds to compute functional connectivity maps. Among all the functional connectivity maps, those generated by motor area (SMA) presented the most consistent spatial distribution with task associated activity map, and the functional connectivity maps generated by primary motor cortex (M1) and dorsal premotor cortex (PMd) consisted of bilateral Ml and SMA. the functional connectivity maps generated by putamen (Pu), thalamus (Th), cerebellum anterior lobe (CbAL) and cerebellum posterior lobe (CbPL) consisted of the areas around the seeds and the mirror areas in the contralateral cortex. Conclusion: Using SMA as seed to compute resting-state functional connectivity map may produce the best spatial coherence with the activity map generated by bilateral hand motor task, and selecting M1 and PMd as seeds may present the best primary motor cortex in the connectivity map. (authors)

Energy dissipation unveils atomic displacement in the noncontact atomic force microscopy imaging of Si(111 )-(7 ×7 )

Science.gov (United States)

Arai, Toyoko; Inamura, Ryo; Kura, Daiki; Tomitori, Masahiko

2018-03-01

The kinetic energy of the oscillating cantilever of noncontact atomic force microscopy (nc-AFM) at room temperature was considerably dissipated over regions between a Si adatom and its neighboring rest atom for Si(111 )-(7 ×7 ) in close proximity to a Si tip on the cantilever. However, nc-AFM topographic images showed no atomic features over those regions, which were the hollow sites of the (7 ×7 ). This energy dissipation likely originated from displacement of Si adatoms with respect to the tip over the hollow sites, leading to a lateral shift of the adatoms toward the rest atom. This interaction led to hysteresis over each cantilever oscillation cycle; when the tip was retracted, the Si adatom likely returned to its original position. To confirm the atomic processes involved in the force interactions through Si dangling bonds, the Si(111 )-(7 ×7 ) surface was partly terminated with atomic hydrogen (H) and examined by nc-AFM. When the Si adatoms and/or the rest atoms were terminated with H, the hollow sites were not bright (less dissipation) in images of the energy dissipation channels by nc-AFM. The hollow sites acted as metastable sites for Si adatoms in surface diffusion and atom manipulation; thus, the dissipation energy which is saturated on the tip likely corresponds to the difference in the potential energy between the hollow site and the Si adatom site. In this study, we demonstrated the ability of dissipation channels of nc-AFM to enable visualization of the dynamics of atoms and molecules on surfaces, which cannot be revealed by nc-AFM topographic images alone.

The acoustic climate at the rest and service areas – parking lots by the Silesian section of A4 motorway

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Robert WIESZAŁA

2012-01-01

Full Text Available The aim of this article is to describe the state of the acoustic climate at the rest and service areas (MOPs situated by A4 motorway in Silesia The analysis includes the research results conducted at these parking lots from May till August 2010. The research was conducted with the digital noise meter, which was connected with the computer during measurement. The research results indicate the essential differences in the noise intensity between the particular rest and service area reaching up to 12 dB(A, in spite of the similar value of the traffic noise in all of the places where the research was conducted. It was assumed that the level of noise on each of the parking lots should be similar to standing norms for the recreation areas i.e. below 55 dB(A. The research conducted at 4 MOPs indicated that only at two of them, MOP Halemba and Wirek, these norms are fulfilled. The lack of the proper anti-noise protection in the form of the sound absorbing screens at the parking lots situated by the motorway causes the situation in which the level of noise at the places devoted to rest highly decreases the possibility to relax before the next stage of a journey.

Wide-area mapping of resting state hemodynamic correlations at microvascular resolution with multi-contrast optical imaging (Conference Presentation)

Science.gov (United States)

Senarathna, Janaka; Hadjiabadi, Darian; Gil, Stacy; Thakor, Nitish V.; Pathak, Arvind P.

2017-02-01

Different brain regions exhibit complex information processing even at rest. Therefore, assessing temporal correlations between regions permits task-free visualization of their `resting state connectivity'. Although functional MRI (fMRI) is widely used for mapping resting state connectivity in the human brain, it is not well suited for `microvascular scale' imaging in rodents because of its limited spatial resolution. Moreover, co-registered cerebral blood flow (CBF) and total hemoglobin (HbT) data are often unavailable in conventional fMRI experiments. Therefore, we built a customized system that combines laser speckle contrast imaging (LSCI), intrinsic optical signal (IOS) imaging and fluorescence imaging (FI) to generate multi-contrast functional connectivity maps at a spatial resolution of 10 μm. This system comprised of three illumination sources: a 632 nm HeNe laser (for LSCI), a 570 nm ± 5 nm filtered white light source (for IOS), and a 473 nm blue laser (for FI), as well as a sensitive CCD camera operating at 10 frames per second for image acquisition. The acquired data enabled visualization of changes in resting state neurophysiology at microvascular spatial scales. Moreover, concurrent mapping of CBF and HbT-based temporal correlations enabled in vivo mapping of how resting brain regions were linked in terms of their hemodynamics. Additionally, we complemented this approach by exploiting the transit times of a fluorescent tracer (Dextran-FITC) to distinguish arterial from venous perfusion. Overall, we demonstrated the feasibility of wide area mapping of resting state connectivity at microvascular resolution and created a new toolbox for interrogating neurovascular function.

Resting eggs in a key player Calanoid copepod in coastal areas. The case of Acartia tonsa (Dana)

DEFF Research Database (Denmark)

Drillet, Guillaume; Hansen, Benni Winding

  Acartia tonsa is an invasive copepod of the European coastal waters, first described in France in 1926, it was found later in most of the European coastal areas. These invasions are believed to come from transport of resting eggs in ships ballast water. In this presentation, I will show the main...

Area-selective atomic layer deposition of platinum using photosensitive polyimide

NARCIS (Netherlands)

Vervuurt, R.H.J.; Sharma, A.; Jiao, Y.; Kessels, W.M.M.; Bol, A.A.

2016-01-01

Area-selective atomic layer deposition (AS-ALD) of platinum (Pt) was studied using photosensitive polyimide as a masking layer. The polyimide films were prepared by spin-coating and patterned using photolithography. AS-ALD of Pt using poly(methyl-methacrylate) (PMMA) masking layers was used as a

Beta Peak Frequencies at Rest Correlate with Endogenous GABA+/Cr Concentrations in Sensorimotor Cortex Areas.

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Thomas J Baumgarten

Full Text Available Neuronal oscillatory activity in the beta band (15-30 Hz is a prominent signal within the human sensorimotor cortex. Computational modeling and pharmacological modulation studies suggest an influence of GABAergic interneurons on the generation of beta band oscillations. Accordingly, studies in humans have demonstrated a correlation between GABA concentrations and power of beta band oscillations. It remains unclear, however, if GABA concentrations also influence beta peak frequencies and whether this influence is present in the sensorimotor cortex at rest and without pharmacological modulation. In the present study, we investigated the relation between endogenous GABA concentration (measured by magnetic resonance spectroscopy and beta oscillations (measured by magnetoencephalography at rest in humans. GABA concentrations and beta band oscillations were measured for left and right sensorimotor and occipital cortex areas. A significant positive linear correlation between GABA concentration and beta peak frequency was found for the left sensorimotor cortex, whereas no significant correlations were found for the right sensorimotor and the occipital cortex. The results show a novel connection between endogenous GABA concentration and beta peak frequency at rest. This finding supports previous results that demonstrated a connection between oscillatory beta activity and pharmacologically modulated GABA concentration in the sensorimotor cortex. Furthermore, the results demonstrate that for a predominantly right-handed sample, the correlation between beta band oscillations and endogenous GABA concentrations is evident only in the left sensorimotor cortex.

Beta Peak Frequencies at Rest Correlate with Endogenous GABA+/Cr Concentrations in Sensorimotor Cortex Areas

Science.gov (United States)

Baumgarten, Thomas J.; Oeltzschner, Georg; Hoogenboom, Nienke; Wittsack, Hans-Jörg; Schnitzler, Alfons; Lange, Joachim

2016-01-01

Neuronal oscillatory activity in the beta band (15–30 Hz) is a prominent signal within the human sensorimotor cortex. Computational modeling and pharmacological modulation studies suggest an influence of GABAergic interneurons on the generation of beta band oscillations. Accordingly, studies in humans have demonstrated a correlation between GABA concentrations and power of beta band oscillations. It remains unclear, however, if GABA concentrations also influence beta peak frequencies and whether this influence is present in the sensorimotor cortex at rest and without pharmacological modulation. In the present study, we investigated the relation between endogenous GABA concentration (measured by magnetic resonance spectroscopy) and beta oscillations (measured by magnetoencephalography) at rest in humans. GABA concentrations and beta band oscillations were measured for left and right sensorimotor and occipital cortex areas. A significant positive linear correlation between GABA concentration and beta peak frequency was found for the left sensorimotor cortex, whereas no significant correlations were found for the right sensorimotor and the occipital cortex. The results show a novel connection between endogenous GABA concentration and beta peak frequency at rest. This finding supports previous results that demonstrated a connection between oscillatory beta activity and pharmacologically modulated GABA concentration in the sensorimotor cortex. Furthermore, the results demonstrate that for a predominantly right-handed sample, the correlation between beta band oscillations and endogenous GABA concentrations is evident only in the left sensorimotor cortex. PMID:27258089

Temporal reliability and lateralization of the resting-state language network.

Science.gov (United States)

Zhu, Linlin; Fan, Yang; Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

2014-01-01

The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

Temporal reliability and lateralization of the resting-state language network.

Directory of Open Access Journals (Sweden)

Linlin Zhu

Full Text Available The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

Temporal Reliability and Lateralization of the Resting-State Language Network

Science.gov (United States)

Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

2014-01-01

The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability. PMID:24475058

Atomic physics using relativistic H- beams

International Nuclear Information System (INIS)

Bryant, H.C.

2005-01-01

Full text: An 8 GeV hydrogen atom can traverse a focused laser beam of width of 1 micron in a time of 353 attoseconds in its rest frame. A design is currently underway at Fermilab for a superconducting linear accelerator that will accelerate H - ions to 8 GeV. This 'Proton Driver' beam is intended to be injected, after stripping down to protons, into the 120 GeV Main Injector for the mass production of neutrinos aimed at a neutrino detector (MINOS) in a mine shaft in Soudan, Minnesota (USA) for the study of neutrino oscillations. It has not passed unnoticed that with some advance planning a few nanoamps from the up-to-250 mA beam could be diverted for atomic physics experiments. Relativistic kinematics enable the creation of extreme conditions for a beam atom. For example, the Doppler shift allows a very large tuning range in the atom's rest frame of a laser beam that is fixed- frequency in the lab. At 8 GeV the rest frame Doppler shift ranges from a factor of 19 in the forward direction to 0.05 backward. The laser intensity is enhanced by the square of the Doppler shift, so that the world's most intense laser beam would be amplified by a factor of 360 in the atom's rest frame. Furthermore, although there are extreme changes in the frequency and intensity in the atom's frame as one changes the intersection angle, the ponderomotive potential remains constant, as it is a relativistic invariant. One of the interesting problems that arises in the planning for this accelerator is the stripping of electrons from the negative ions by photodetachment from Doppler shifted thermal photons. We estimate that, if the transfer lines are kept at 300 K (room temperature), the mean free path at 8 GeV for stripping from collisions with cavity radiation is about 1300 km. The physics of the interactions of such a beam with very thin material foils, again in the attosecond regime, has been treated theoretically, but has not been studied experimentally at such high energies. We will

Correlated Disruption of Resting-State fMRI, LFP, and Spike Connectivity between Area 3b and S2 following Spinal Cord Injury in Monkeys.

Science.gov (United States)

Wu, Ruiqi; Yang, Pai-Feng; Chen, Li Min

2017-11-15

This study aims to understand how functional connectivity (FC) between areas 3b and S2 alters following input deprivation and the neuronal basis of disrupted FC of resting-state fMRI signals. We combined submillimeter fMRI with microelectrode recordings to localize the deafferented digit regions in areas 3b and S2 by mapping tactile stimulus-evoked fMRI activations before and after cervical dorsal column lesion in each male monkey. An average afferent disruption of 97% significantly reduced fMRI, local field potential (LFP), and spike responses to stimuli in both areas. Analysis of resting-state fMRI signal correlation, LFP coherence, and spike cross-correlation revealed significantly reduced functional connectivity between deafferented areas 3b and S2. The degrees of reductions in stimulus responsiveness and FC after deafferentation differed across fMRI, LFP, and spiking signals. The reduction of FC was much weaker than that of stimulus-evoked responses. Whereas the largest stimulus-evoked signal drop (∼80%) was observed in LFP signals, the greatest FC reduction was detected in the spiking activity (∼30%). fMRI signals showed mild reductions in stimulus responsiveness (∼25%) and FC (∼20%). The overall deafferentation-induced changes were quite similar in areas 3b and S2 across signals. Here we demonstrated that FC strength between areas 3b and S2 was much weakened by dorsal column lesion, and stimulus response reduction and FC disruption in fMRI covary with those of LFP and spiking signals in deafferented areas 3b and S2. These findings have important implications for fMRI studies aiming to probe FC alterations in pathological conditions involving deafferentation in humans. SIGNIFICANCE STATEMENT By directly comparing fMRI, local field potential, and spike signals in both tactile stimulation and resting states before and after severe disruption of dorsal column afferent, we demonstrated that reduction in fMRI responses to stimuli is accompanied by weakened

Alterations in task-induced activity and resting-state fluctuations in visual and DMN areas revealed in long-term meditators.

Science.gov (United States)

Berkovich-Ohana, Aviva; Harel, Michal; Hahamy, Avital; Arieli, Amos; Malach, Rafael

2016-07-15

Recently we proposed that the information contained in spontaneously emerging (resting-state) fluctuations may reflect individually unique neuro-cognitive traits. One prediction of this conjecture, termed the "spontaneous trait reactivation" (STR) hypothesis, is that resting-state activity patterns could be diagnostic of unique personalities, talents and life-styles of individuals. Long-term meditators could provide a unique experimental group to test this hypothesis. Using fMRI we found that, during resting-state, the amplitude of spontaneous fluctuations in long-term mindfulness meditation (MM) practitioners was enhanced in the visual cortex and significantly reduced in the DMN compared to naïve controls. Importantly, during a visual recognition memory task, the MM group showed heightened visual cortex responsivity, concomitant with weaker negative responses in Default Mode Network (DMN) areas. This effect was also reflected in the behavioral performance, where MM practitioners performed significantly faster than the control group. Thus, our results uncover opposite changes in the visual and default mode systems in long-term meditators which are revealed during both rest and task. The results support the STR hypothesis and extend it to the domain of local changes in the magnitude of the spontaneous fluctuations. Copyright © 2016 Elsevier Inc. All rights reserved.

PreSurgMapp: a MATLAB Toolbox for Presurgical Mapping of Eloquent Functional Areas Based on Task-Related and Resting-State Functional MRI.

Science.gov (United States)

Huang, Huiyuan; Ding, Zhongxiang; Mao, Dewang; Yuan, Jianhua; Zhu, Fangmei; Chen, Shuda; Xu, Yan; Lou, Lin; Feng, Xiaoyan; Qi, Le; Qiu, Wusi; Zhang, Han; Zang, Yu-Feng

2016-10-01

The main goal of brain tumor surgery is to maximize tumor resection while minimizing the risk of irreversible postoperative functional sequelae. Eloquent functional areas should be delineated preoperatively, particularly for patients with tumors near eloquent areas. Functional magnetic resonance imaging (fMRI) is a noninvasive technique that demonstrates great promise for presurgical planning. However, specialized data processing toolkits for presurgical planning remain lacking. Based on several functions in open-source software such as Statistical Parametric Mapping (SPM), Resting-State fMRI Data Analysis Toolkit (REST), Data Processing Assistant for Resting-State fMRI (DPARSF) and Multiple Independent Component Analysis (MICA), here, we introduce an open-source MATLAB toolbox named PreSurgMapp. This toolbox can reveal eloquent areas using comprehensive methods and various complementary fMRI modalities. For example, PreSurgMapp supports both model-based (general linear model, GLM, and seed correlation) and data-driven (independent component analysis, ICA) methods and processes both task-based and resting-state fMRI data. PreSurgMapp is designed for highly automatic and individualized functional mapping with a user-friendly graphical user interface (GUI) for time-saving pipeline processing. For example, sensorimotor and language-related components can be automatically identified without human input interference using an effective, accurate component identification algorithm using discriminability index. All the results generated can be further evaluated and compared by neuro-radiologists or neurosurgeons. This software has substantial value for clinical neuro-radiology and neuro-oncology, including application to patients with low- and high-grade brain tumors and those with epilepsy foci in the dominant language hemisphere who are planning to undergo a temporal lobectomy.

Clinical applications of resting state functional connectivity

Directory of Open Access Journals (Sweden)

Michael D Fox

2010-06-01

Full Text Available During resting conditions the brain remains functionally and metabolically active. One manifestation of this activity that has become an important research tool is spontaneous fluctuations in the blood oxygen level dependent (BOLD signal of fMRI. The identification of correlation patterns in these spontaneous fluctuations has been termed resting state functional connectivity (fcMRI and has the potential to greatly increase the translation of fMRI into clinical care. In this article we review the advantages of the resting state signal for clinical applications including detailed discussion of signal to noise considerations. We include guidelines for performing resting state research on clinical populations, outline the different areas for clinical application, and identify important barriers to be addressed to facilitate the translation of resting state fcMRI into the clinical realm.

On the spontaneous radiative decay of a moving atom

International Nuclear Information System (INIS)

Voitkiv, A B; Najjari, B; Ullrich, J

2007-01-01

We consider the relationship between the spontaneous radiative decay of an atom at rest and of an atom moving with a constant velocity. Based on the relativistic form, A μ j μ , of the field-current interaction we analyse two situations. In the first of them the radiative decay of a single atom is considered by using two different reference frames. In the second, a single reference frame is used to describe the radiative decay of two identical atoms, one of which is at rest in this frame and the other one moves with a constant velocity. Although in special relativity only the relative velocity between a source and an observer matters, there are subtle differences in the analysis of these situations: within the framework of the first situation one deals only with the Lorentz transformation, which is insensitive to whether exact or approximate atomic wave functions are used in the analysis, whereas the analysis of the second situation involves a gauge transformation which in general is not compatible with using approximate atomic wave functions. We have also shown that this gauge transformation can be used as a test for the accuracy of approximate atomic states obtained in atomic structure calculations

Changes in neural resting state activity in primary and higher-order motor areas induced by a short sensorimotor intervention based on the Feldenkrais method

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Julius eVerrel

2015-04-01

Full Text Available We use functional magnetic resonance imaging to investigate short-term neural effects of a brief sensorimotor intervention adapted from the Feldenkrais method, a movement-based learning method. Twenty-one participants (10 men, 19-30 years took part in the study. Participants were in a supine position in the scanner with extended legs while an experienced Feldenkrais practitioner used a planar board to touch and apply minimal force to different parts of the sole and toes of their left foot under two experimental conditions. In the local condition, the practitioner explored movement within foot and ankle. In the global condition, the practitioner focused on the connection and support from the foot to the rest of the body. Before (baseline and after each intervention (post-local, post-global, we measured brain activity during intermittent pushing/releasing with the left leg and during resting state. Independent localizer tasks were used to identify regions of interest (ROI.Brain activity during left-foot pushing did not significantly differ between conditions in sensorimotor areas. Resting state activity (regional homogeneity, ReHo increased from baseline to post-local in medial right motor cortex, and from baseline to post-global in the left supplementary/cingulate motor area. Contrasting post-global to post-local showed higher ReHo in right lateral motor cortex. ROI analyses showed significant increases in ReHo in pushing-related areas from baseline to both post-local and post-global, and this increase tended to be more pronounced post-local. The results of this exploratory study show that a short, non-intrusive sensorimotor intervention can have short-term effects on spontaneous cortical activity in functionally related brain regions. Increased resting state activity in higher-order motor areas supports the hypothesis that the global intervention engages action-related neural processes.

Effect of space availability at feed bunk and rest area on metabolic conditions and productive responses in dairy cows

Directory of Open Access Journals (Sweden)

L. Stefanini

2011-03-01

Full Text Available It has been estimated that dairy cows spend 3 to 5 h/d eating, consuming 9 to 14 meals per day. In addition, they ruminate 7 to 10 h/d, spend approximately 30 min/d drinking, 2 to 3 h/d being milked, and require approximately 10 h/d for lying time (Grant and Albright, 2000. Management decisions on dairy must not interfere with the cow’s ability to perform these activities which comprises her daily routines. It is well known that feed bunk space modifies eating behaviour, while the amount and characteristics of rest area modify resting activity of the cows. The traditional recommendation of 0.6 linear meter of bunk space per cow is the minimal amount of space needed for all cows to eat at one time (Grant and Albright, 2001.......

Efficiency at rest: magnetoencephalographic resting-state connectivity and individual differences in verbal working memory.

Science.gov (United States)

del Río, David; Cuesta, Pablo; Bajo, Ricardo; García-Pacios, Javier; López-Higes, Ramón; del-Pozo, Francisco; Maestú, Fernando

2012-11-01

Inter-individual differences in cognitive performance are based on an efficient use of task-related brain resources. However, little is known yet on how these differences might be reflected on resting-state brain networks. Here we used Magnetoencephalography resting-state recordings to assess the relationship between a behavioral measurement of verbal working memory and functional connectivity as measured through Mutual Information. We studied theta (4-8 Hz), low alpha (8-10 Hz), high alpha (10-13 Hz), low beta (13-18 Hz) and high beta (18-30 Hz) frequency bands. A higher verbal working memory capacity was associated with a lower mutual information in the low alpha band, prominently among right-anterior and left-lateral sensors. The results suggest that an efficient brain organization in the domain of verbal working memory might be related to a lower resting-state functional connectivity across large-scale brain networks possibly involving right prefrontal and left perisylvian areas. Copyright © 2012 Elsevier B.V. All rights reserved.

A protected area at the Ezeiza Atomic Centre?

International Nuclear Information System (INIS)

Kundt, Miriam S.; Furnari, Juan C.

2008-01-01

There is a growing concern among the populations regarding environmental pollution that can affects our quality of life, the biodiversity and the entire planet. This concern has led to the signing of international legal conventions in the framework of the United Nations Conference on Environment and Development. This paper considers the relevance of establishing a space for the protection of nature and for academic studies related to the environment at the Ezeiza Atomic Center. The Center is located in the outskirt s of the urban most populous region of the country and it is one of the few green spaces in the area that contributes to the quality of urban environment. It is also a refuge of natural wildlife to the Pampean eco region. (author) [es

An atomic empire a technical history of the rise and fall of the British atomic energy programme

CERN Document Server

Hill, C N

2013-01-01

Britain was the first country to exploit atomic energy on a large scale, and at its peak in the mid-1960s, it had generated more electricity from nuclear power than the rest of the world combined.The civil atomic energy programme grew out of the military programme which produced plutonium for atomic weapons. In 1956, Calder Hall power station was opened by the Queen. The very next year, one of the early Windscale reactors caught fire and the world's first major nuclear accident occurred.The civil programme ran into further difficulty in the mid-1960s and as a consequence of procrastination in

Patterns of resting state connectivity in human primary visual cortical areas: a 7T fMRI study

NARCIS (Netherlands)

Raemaekers, Mathijs; Schellekens, Wouter; van Wezel, Richard Jack Anton; Petridou, Natalia; Kristo, Gert; Ramsey, Nick F.

2014-01-01

The nature and origin of fMRI resting state fluctuations and connectivity are still not fully known. More detailed knowledge on the relationship between resting state patterns and brain function may help to elucidate this matter. We therefore performed an in depth study of how resting state

Electron affinities of atoms, molecules, and radicals

International Nuclear Information System (INIS)

Christodoulides, A.A.; McCorkle, D.L.; Christophorou, L.G.

1982-01-01

We review briefly but comprehensively the theoretical, semiempirical and experimental methods employed to determine electron affinities (EAs) of atoms, molecules and radicals, and summarize the EA data obtained by these methods. The detailed processes underlying the principles of the experimental methods are discussed very briefly. It is, nonetheless, instructive to recapitulate the definition of EA and those of the related quantities, namely, the vertical detachment energy, VDE, and the vertical attachment energy, VAE. The EA of an atom is defined as the difference in total energy between the ground state of the neutral atom (plus the electron at rest at infinity) and its negative ion. The EA of a molecule is defined as the difference in energy between the neutral molecule plus an electron at rest at infinity and the molecular negative ion when both, the neutral molecules and the negative ion, are in their ground electronic, vibrational and rotational states. The VDE is defined as the minimum energy required to eject the electron from the negative ion (in its ground electronic and nuclear state) without changing the internuclear separation; since the vertical transition may leave the neutral molecule in an excited vibrational/rotational state, the VDE, although the same as the EA for atoms is, in general, different (larger than), from the EA for molecules. Similarly, the VAE is defined as the difference in energy between the neutral molecule in its ground electronic, vibrational and rotational states plus an electron at rest at infinity and the molecular negative ion formed by addition of an electron to the neutral molecule without allowing a change in the intermolecular separation of the constituent nuclei; it is a quantity appropriate to those cases where the lowest negative ion state lies above the ground states of the neutral species and is less or equal to EA

Predictive Modeling of Spinner Dolphin (Stenella longirostris) Resting Habitat in the Main Hawaiian Islands

Science.gov (United States)

Thorne, Lesley H.; Johnston, David W.; Urban, Dean L.; Tyne, Julian; Bejder, Lars; Baird, Robin W.; Yin, Suzanne; Rickards, Susan H.; Deakos, Mark H.; Mobley, Joseph R.; Pack, Adam A.; Chapla Hill, Marie

2012-01-01

Predictive habitat models can provide critical information that is necessary in many conservation applications. Using Maximum Entropy modeling, we characterized habitat relationships and generated spatial predictions of spinner dolphin (Stenella longirostris) resting habitat in the main Hawaiian Islands. Spinner dolphins in Hawai'i exhibit predictable daily movements, using inshore bays as resting habitat during daylight hours and foraging in offshore waters at night. There are growing concerns regarding the effects of human activities on spinner dolphins resting in coastal areas. However, the environmental factors that define suitable resting habitat remain unclear and must be assessed and quantified in order to properly address interactions between humans and spinner dolphins. We used a series of dolphin sightings from recent surveys in the main Hawaiian Islands and a suite of environmental variables hypothesized as being important to resting habitat to model spinner dolphin resting habitat. The model performed well in predicting resting habitat and indicated that proximity to deep water foraging areas, depth, the proportion of bays with shallow depths, and rugosity were important predictors of spinner dolphin habitat. Predicted locations of suitable spinner dolphin resting habitat provided in this study indicate areas where future survey efforts should be focused and highlight potential areas of conflict with human activities. This study provides an example of a presence-only habitat model used to inform the management of a species for which patterns of habitat availability are poorly understood. PMID:22937022

Deeply bound pionic atom

International Nuclear Information System (INIS)

Toki, Hiroshi; Yamazaki, Toshimitsu

1989-01-01

The standard method of pionic atom formation does not produce deeply bound pionic atoms. A study is made on the properties of deeply bound pionic atom states by using the standard pion-nucleus optical potential. Another study is made to estimate the cross sections of the formation of ls pionic atom states by various methods. The pion-nucleus optical potential is determined by weakly bound pionic atom states and pion nucleus scattering. Although this potential may not be valid for deeply bound pionic atoms, it should provide some hint on binding energies and level widths of deeply bound states. The width of the ls state comes out to be 0.3 MeV and is well separated from the rest. The charge dependence of the ls state is investigated. The binding energies and the widths increase linearly with Z azbove a Z of 30. The report then discusses various methods to populate deeply bound pionic atoms. In particular, 'pion exchange' reactions are proposed. (n, pπ) reaction is discussed first. The cross section is calculated by assuming the in- and out-going nucleons on-shell and the produced pion in (n1) pionic atom states. Then, (n, dπ - ) cross sections are estimated. (p, 2 Heπ - ) reaction would have cross sections similar to the cross section of (n, dπ - ) reaction. In conclusion, it seems best to do (n, p) experiment on heavy nuclei for deeply bound pionic atom. (Nogami, K.)

Resting state fMRI: A review on methods in resting state connectivity analysis and resting state networks.

Science.gov (United States)

Smitha, K A; Akhil Raja, K; Arun, K M; Rajesh, P G; Thomas, Bejoy; Kapilamoorthy, T R; Kesavadas, Chandrasekharan

2017-08-01

The inquisitiveness about what happens in the brain has been there since the beginning of humankind. Functional magnetic resonance imaging is a prominent tool which helps in the non-invasive examination, localisation as well as lateralisation of brain functions such as language, memory, etc. In recent years, there is an apparent shift in the focus of neuroscience research to studies dealing with a brain at 'resting state'. Here the spotlight is on the intrinsic activity within the brain, in the absence of any sensory or cognitive stimulus. The analyses of functional brain connectivity in the state of rest have revealed different resting state networks, which depict specific functions and varied spatial topology. However, different statistical methods have been introduced to study resting state functional magnetic resonance imaging connectivity, yet producing consistent results. In this article, we introduce the concept of resting state functional magnetic resonance imaging in detail, then discuss three most widely used methods for analysis, describe a few of the resting state networks featuring the brain regions, associated cognitive functions and clinical applications of resting state functional magnetic resonance imaging. This review aims to highlight the utility and importance of studying resting state functional magnetic resonance imaging connectivity, underlining its complementary nature to the task-based functional magnetic resonance imaging.

RESTful NET

CERN Document Server

Flanders, Jon

2008-01-01

RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

Long range stress correlations in the inherent structures of liquids at rest

Energy Technology Data Exchange (ETDEWEB)

Chowdhury, Sadrul; Abraham, Sneha; Hudson, Toby; Harrowell, Peter [School of Chemistry, University of Sydney, Sydney, NSW 2006 (Australia)

2016-03-28

Simulation studies of the atomic shear stress in the local potential energy minima (inherent structures) are reported for binary liquid mixtures in 2D and 3D. These inherent structure stresses are fundamental to slow stress relaxation and high viscosity in supercooled liquids. We find that the atomic shear stress in the inherent structures (IS’s) of both liquids at rest exhibits slowly decaying anisotropic correlations. We show that the stress correlations contribute significantly to the variance of the total shear stress of the IS configurations and consider the origins of the anisotropy and spatial extent of the stress correlations.

Geneva University: On our way to anti-hydrogen at rest

CERN Multimedia

Geneva University

2010-01-01

Ecole de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 GENEVA 4 Tel: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 28 April 2010 PARTICLE PHYSICS SEMINAR at 17.00 hrs – Stückelberg Auditorium On our way to anti-hydrogen at rest Prof. Walter Oelert, Research Center Jülich, Germany Trapped cold atoms of anti-hydrogen are optimal for testing possible CPT violations in comparison of spectral lines and gravitational effects on matter and anti-matter. For this reason it is mandatory to optimize the properties of the clouds of anti-protons and positrons used to produce the anti-hydrogen atoms. The ATRAP-collaboration at CERNs AD did perform such experiments by studying the temperature of these clouds and their stability at different conditions. Though detailed tests have been performed to verify the trapping of anti-hydrogen atoms in a magnetic gradient field no statistically significant signal was detected yet. Re...

Resting-state brain activity in adult males who stutter.

Directory of Open Access Journals (Sweden)

Yun Xuan

Full Text Available Although developmental stuttering has been extensively studied with structural and task-based functional magnetic resonance imaging (fMRI, few studies have focused on resting-state brain activity in this disorder. We investigated resting-state brain activity of stuttering subjects by analyzing the amplitude of low-frequency fluctuation (ALFF, region of interest (ROI-based functional connectivity (FC and independent component analysis (ICA-based FC. Forty-four adult males with developmental stuttering and 46 age-matched fluent male controls were scanned using resting-state fMRI. ALFF, ROI-based FCs and ICA-based FCs were compared between male stuttering subjects and fluent controls in a voxel-wise manner. Compared with fluent controls, stuttering subjects showed increased ALFF in left brain areas related to speech motor and auditory functions and bilateral prefrontal cortices related to cognitive control. However, stuttering subjects showed decreased ALFF in the left posterior language reception area and bilateral non-speech motor areas. ROI-based FC analysis revealed decreased FC between the posterior language area involved in the perception and decoding of sensory information and anterior brain area involved in the initiation of speech motor function, as well as increased FC within anterior or posterior speech- and language-associated areas and between the prefrontal areas and default-mode network (DMN in stuttering subjects. ICA showed that stuttering subjects had decreased FC in the DMN and increased FC in the sensorimotor network. Our findings support the concept that stuttering subjects have deficits in multiple functional systems (motor, language, auditory and DMN and in the connections between them.

Resting-State Brain Activity in Adult Males Who Stutter

Science.gov (United States)

Zhu, Chaozhe; Wang, Liang; Yan, Qian; Lin, Chunlan; Yu, Chunshui

2012-01-01

Although developmental stuttering has been extensively studied with structural and task-based functional magnetic resonance imaging (fMRI), few studies have focused on resting-state brain activity in this disorder. We investigated resting-state brain activity of stuttering subjects by analyzing the amplitude of low-frequency fluctuation (ALFF), region of interest (ROI)-based functional connectivity (FC) and independent component analysis (ICA)-based FC. Forty-four adult males with developmental stuttering and 46 age-matched fluent male controls were scanned using resting-state fMRI. ALFF, ROI-based FCs and ICA-based FCs were compared between male stuttering subjects and fluent controls in a voxel-wise manner. Compared with fluent controls, stuttering subjects showed increased ALFF in left brain areas related to speech motor and auditory functions and bilateral prefrontal cortices related to cognitive control. However, stuttering subjects showed decreased ALFF in the left posterior language reception area and bilateral non-speech motor areas. ROI-based FC analysis revealed decreased FC between the posterior language area involved in the perception and decoding of sensory information and anterior brain area involved in the initiation of speech motor function, as well as increased FC within anterior or posterior speech- and language-associated areas and between the prefrontal areas and default-mode network (DMN) in stuttering subjects. ICA showed that stuttering subjects had decreased FC in the DMN and increased FC in the sensorimotor network. Our findings support the concept that stuttering subjects have deficits in multiple functional systems (motor, language, auditory and DMN) and in the connections between them. PMID:22276215

The generation of resting membrane potentials in an inner ear hair cell system.

Science.gov (United States)

Bracho, H; Budelli, R

1978-01-01

1. The macula sacculi in the mudpuppy is an inner ear sensory area accessible for intracellular recordings in vitro and in vivo. 2. The resting potentials recorded in vitro can be explained by the electrodiffusion theory assuming a uniform ionic selective in the membranes of the neuroepithelial cells. 3. The resting potentials recorded in vivo are significantly larger than predicted by the electrodiffusion theory, probably because of an electrogenic metabolic process present in the neuroepithelial cells. 4. An equivalent circuit is proposed to explain the resting electrogenesis in the neuroepithelial cells present in the sensory area. Images Plate 1 PMID:702400

Interaction of relativistic elementary atoms with matter. I. General formulas

International Nuclear Information System (INIS)

Mrowczyn'ski, S.

1987-01-01

The problem of the interaction of relativistic elementary atoms (Coulomb bound states of elementary particles such as positronium, pionium, etc.) with matter is studied in the reference frame where the atom is initially at rest. An atom of matter is treated as a spinless structureless fast particle. The amplitudes of elementary-atom interaction are derived in the Born approximation under the assumption that a momentum transfer to the atom does not significantly exceed an inverse Bohr radius of the atom. The elementary-atom excitation and ionization processes are considered. The transitions where the spin projection of the atom component is reversed are also studied. In particular the matrix elements for para-ortho and ortho-para transitions are given. The spin structure of the amplitudes is discussed in detail. The sum rules, which allow the calculation of the cross sections summed over atom final states are found. Finally the formulas of the atom interaction cross sections are presented

Increased neuronal firing in resting and sleep in areas of the macaque medial prefrontal cortex.

Science.gov (United States)

Gabbott, Paul L; Rolls, Edmund T

2013-06-01

The medial prefrontal cortex (mPFC) of humans and macaques is an integral part of the default mode network and is a brain region that shows increased activation in the resting state. A previous paper from our laboratory reported significantly increased firing rates of neurons in the macaque subgenual cingulate cortex, Brodmann area (BA) 25, during disengagement from a task and also during slow wave sleep [E.T. Rolls et al. (2003) J. Neurophysiology, 90, 134-142]. Here we report the finding that there are neurons in other areas of mPFC that also increase their firing rates during disengagement from a task, drowsiness and eye-closure. During the neurophysiological recording of single mPFC cells (n = 249) in BAs 9, 10, 13 m, 14c, 24b and especially pregenual area 32, populations of neurons were identified whose firing rates altered significantly with eye-closure compared with eye-opening. Three types of neuron were identified: Type 1 cells (28.1% of the total population) significantly increased (mean + 329%; P ≪ 0.01) their average firing rate with eye-closure, from 3.1 spikes/s when awake to 10.2 spikes/s when asleep; Type 2 cells (6.0%) significantly decreased (mean -68%; P areas of mPFC, implicated in the anterior default mode network, there is a substantial population of neurons that significantly increase their firing rates during periods of eye-closure. Such neurons may be part of an interconnected network of distributed brain regions that are more active during periods of relaxed wakefulness than during attention-demanding tasks. © 2013 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

102(ℎ/2π)k Large Area Atom Interferometers

International Nuclear Information System (INIS)

Chiow, Sheng-wey; Kovachy, Tim; Chien, Hui-Chun; Kasevich, Mark A.

2011-01-01

We demonstrate atom interferometers utilizing a novel beam splitter based on sequential multiphoton Bragg diffractions. With this sequential Bragg large momentum transfer (SB-LMT) beam splitter, we achieve high contrast atom interferometers with momentum splittings of up to 102 photon recoil momenta (102(ℎ/2π)k). To our knowledge, this is the highest momentum splitting achieved in any atom interferometer, advancing the state-of-the-art by an order of magnitude. We also demonstrate strong noise correlation between two simultaneous SB-LMT interferometers, which alleviates the need for ultralow noise lasers and ultrastable inertial environments in some future applications. Our method is intrinsically scalable and can be used to dramatically increase the sensitivity of atom interferometers in a wide range of applications, including inertial sensing, measuring the fine structure constant, and detecting gravitational waves.

Atomic polarizabilities

International Nuclear Information System (INIS)

Safronova, M. S.; Mitroy, J.; Clark, Charles W.; Kozlov, M. G.

2015-01-01

The atomic dipole polarizability governs the first-order response of an atom to an applied electric field. Atomic polarization phenomena impinge upon a number of areas and processes in physics and have been the subject of considerable interest and heightened importance in recent years. In this paper, we will summarize some of the recent applications of atomic polarizability studies. A summary of results for polarizabilities of noble gases, monovalent, and divalent atoms is given. The development of the CI+all-order method that combines configuration interaction and linearized coupled-cluster approaches is discussed

Atomic polarizabilities

Energy Technology Data Exchange (ETDEWEB)

Safronova, M. S. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Mitroy, J. [School of Engineering, Charles Darwin University, Darwin NT 0909 (Australia); Clark, Charles W. [Joint Quantum Institute, National Institute of Standards and Technology and the University of Maryland, Gaithersburg, Maryland 20899-8410 (United States); Kozlov, M. G. [Petersburg Nuclear Physics Institute, Gatchina 188300 (Russian Federation)

2015-01-22

The atomic dipole polarizability governs the first-order response of an atom to an applied electric field. Atomic polarization phenomena impinge upon a number of areas and processes in physics and have been the subject of considerable interest and heightened importance in recent years. In this paper, we will summarize some of the recent applications of atomic polarizability studies. A summary of results for polarizabilities of noble gases, monovalent, and divalent atoms is given. The development of the CI+all-order method that combines configuration interaction and linearized coupled-cluster approaches is discussed.

REST: a toolkit for resting-state functional magnetic resonance imaging data processing.

Directory of Open Access Journals (Sweden)

Xiao-Wei Song

Full Text Available Resting-state fMRI (RS-fMRI has been drawing more and more attention in recent years. However, a publicly available, systematically integrated and easy-to-use tool for RS-fMRI data processing is still lacking. We developed a toolkit for the analysis of RS-fMRI data, namely the RESting-state fMRI data analysis Toolkit (REST. REST was developed in MATLAB with graphical user interface (GUI. After data preprocessing with SPM or AFNI, a few analytic methods can be performed in REST, including functional connectivity analysis based on linear correlation, regional homogeneity, amplitude of low frequency fluctuation (ALFF, and fractional ALFF. A few additional functions were implemented in REST, including a DICOM sorter, linear trend removal, bandpass filtering, time course extraction, regression of covariates, image calculator, statistical analysis, and slice viewer (for result visualization, multiple comparison correction, etc.. REST is an open-source package and is freely available at http://www.restfmri.net.

Increased interhemispheric resting-state functional connectivity after sleep deprivation: a resting-state fMRI study.

Science.gov (United States)

Zhu, Yuanqiang; Feng, Zhiyan; Xu, Junling; Fu, Chang; Sun, Jinbo; Yang, Xuejuan; Shi, Dapeng; Qin, Wei

2016-09-01

Several functional imaging studies have investigated the regional effects of sleep deprivation (SD) on impaired brain function; however, potential changes in the functional interactions between the cerebral hemispheres after SD are not well understood. In this study, we used a recently validated approach, voxel-mirrored homotopic connectivity (VMHC), to directly examine the changes in interhemispheric homotopic resting-state functional connectivity (RSFC) after SD. Resting-state functional MRI (fMRI) was performed in 28 participants both after rest wakefulness (RW) and a total night of SD. An interhemispheric RSFC map was obtained by calculating the Pearson correlation (Fisher Z transformed) between each pair of homotopic voxel time series for each subject in each condition. The between-condition differences in interhemispheric RSFC were then examined at global and voxelwise levels separately. Significantly increased global VMHC was found after sleep deprivation; specifically, a significant increase in VMHC was found in specific brain regions, including the thalamus, paracentral lobule, supplementary motor area, postcentral gyrus and lingual gyrus. No regions showed significantly reduced VMHC after sleep deprivation. Further analysis indicates that these findings did not depend on the various sizes of smoothing kernels that were adopted in the preprocessing steps and that the differences in these regions were still significant with or without global signal regression. Our data suggest that the increased VMHC might reflect the compensatory involvement of bilateral brain areas, especially the bilateral thalamus, to prevent cognitive performance deterioration when sleep pressure is elevated after sleep deprivation. Our findings provide preliminary evidence of interhemispheric correlation changes after SD and contribute to a better understanding of the neural mechanisms of SD.

The Amsterdam Resting-State Questionnaire reveals multiple phenotypes of resting-state cognition

Science.gov (United States)

Diaz, B. Alexander; Van Der Sluis, Sophie; Moens, Sarah; Benjamins, Jeroen S.; Migliorati, Filippo; Stoffers, Diederick; Den Braber, Anouk; Poil, Simon-Shlomo; Hardstone, Richard; Van't Ent, Dennis; Boomsma, Dorret I.; De Geus, Eco; Mansvelder, Huibert D.; Van Someren, Eus J. W.; Linkenkaer-Hansen, Klaus

2013-01-01

Resting-state neuroimaging is a dominant paradigm for studying brain function in health and disease. It is attractive for clinical research because of its simplicity for patients, straightforward standardization, and sensitivity to brain disorders. Importantly, non-sensory experiences like mind wandering may arise from ongoing brain activity. However, little is known about the link between ongoing brain activity and cognition, as phenotypes of resting-state cognition—and tools to quantify them—have been lacking. To facilitate rapid and structured measurements of resting-state cognition we developed a 50-item self-report survey, the Amsterdam Resting-State Questionnaire (ARSQ). Based on ARSQ data from 813 participants assessed after 5 min eyes-closed rest in their home, we identified seven dimensions of resting-state cognition using factor analysis: Discontinuity of Mind, Theory of Mind, Self, Planning, Sleepiness, Comfort, and Somatic Awareness. Further, we showed that the structure of cognition was similar during resting-state fMRI and EEG, and that the test-retest correlations were remarkably high for all dimensions. To explore whether inter-individual variation of resting-state cognition is related to health status, we correlated ARSQ-derived factor scores with psychometric scales measuring depression, anxiety, and sleep quality. Mental health correlated positively with Comfort and negatively with Discontinuity of Mind. Finally, we show that sleepiness may partially explain a resting-state EEG profile previously associated with Alzheimer's disease. These findings indicate that the ARSQ readily provides information about cognitive phenotypes and that it is a promising tool for research on the neural correlates of resting-state cognition in health and disease. PMID:23964225

Atomic imaging of an InSe single-crystal surface with atomic force microscope

OpenAIRE

Uosaki, Kohei; Koinuma, Michio

1993-01-01

The atomic force microscope was employed to observed in air the surface atomic structure of InSe, one of III-VI compound semiconductors with layered structures. Atomic arrangements were observed in both n-type and p-type materials. The observed structures are in good agreement with those expected from bulk crystal structures. The atomic images became less clear by repeating the imaging process. Wide area imaging after the imaging of small area clearly showed that a mound was created at the sp...

Decreased functional connectivity between ventral tegmental area and nucleus accumbens in Internet gaming disorder: evidence from resting state functional magnetic resonance imaging.

Science.gov (United States)

Zhang, Jin-Tao; Ma, Shan-Shan; Yip, Sarah W; Wang, Ling-Jiao; Chen, Chao; Yan, Chao-Gan; Liu, Lu; Liu, Ben; Deng, Lin-Yuan; Liu, Qin-Xue; Fang, Xiao-Yi

2015-11-18

Internet gaming disorder (IGD) has become an increasing mental health problem worldwide. Decreased resting-state functional connectivity (rsFC) between the ventral tegmental area (VTA) and the nucleus accumbens (NAcc) has been found in substance use and is thought to play an important role in the development of substance addiction. However, rsFC between the VTA and NAcc in a non-substance addiction, such as IGD, has not been assessed previously. The current study aimed to investigate: (1) if individuals with IGD exhibit alterations in VTA-NAcc functional connectivity; and (2) whether VTA-NAcc functional connectivity is associated with subjective Internet craving. Thirty-five male participants with IGD and 24 healthy control (HC) individuals participated in resting-state functional magnetic resonance imaging. Regions of interest (left NAcc, right NAcc and VTA) were selected based on the literature and were defined by placing spheres centered on Talairach Daemon coordinates. In comparison with HCs, individuals with IGD had significantly decreased rsFC between the VTA and right NAcc. Resting-state functional connectivity strength between the VTA and right NAcc was negatively correlated with self-reported subjective craving for the Internet. These results suggest possible neural functional similarities between individuals with IGD and individuals with substance addictions.

REST based mobile applications

Science.gov (United States)

Rambow, Mark; Preuss, Thomas; Berdux, Jörg; Conrad, Marc

2008-02-01

Simplicity is the major advantage of REST based webservices. Whereas SOAP is widespread in complex, security sensitive business-to-business aplications, REST is widely used for mashups and end-user centric applicatons. In that context we give an overview of REST and compare it to SOAP. Furthermore we apply the GeoDrawing application as an example for REST based mobile applications and emphasize on pros and cons for the use of REST in mobile application scenarios.

Wavepacket dynamics of a Rydberg atom monitored by a pair of time-delayed laser pulses

Science.gov (United States)

Xin, PeiPei; Cheng, Hong; Zhang, ShanShan; Wang, HanMu; Liu, HongPing

2018-02-01

We have investigated the Rydberg state population of an argon atom by an intense laser pulse and its wavepacket dynamics monitored by another successive laser pulse in the tunneling regime. A wavepacket comprising a superposition of close high-lying Rydberg states is irradiated by a multicycle laser pulse, where the sub-wave components in the wavepacket have fixed relative phases. A time-delayed second laser pulse is employed to apply on the excited Rydberg atom. If the time is properly chosen, one of the sub-wave components will be guided towards the ionization area while the rest remains intact. By means of this pump-probe technique, we could control and monitor the Rydberg wavepacket dynamics and reveal some interesting phenomenon such as the survival rate of individual Rydberg states related to the classical orbital period of electron.

Young Investigator Proposal, Research Area 7.4 Reactive Chemical Systems: Multifunctional, Bimetallic Nanomaterials Prepared by Atomic Layer Electroless Deposition

Science.gov (United States)

2017-09-30

Report: Young Investigator Proposal, Research Area 7.4 Reactive Chemical Systems: Multifunctional, Bimetallic Nanomaterials Prepared by Atomic Layer ...Chemical Systems: Multifunctional, Bimetallic Nanomaterials Prepared by Atomic Layer Electroless Deposition Report Term: 0-Other Email: pcappillino... Layer Electroless Deposition (ALED, Figure 1) is the ability to tune growth mechanism, hence growth morphology, by altering conditions. In this

Advances in atomic spectroscopy

CERN Document Server

Sneddon, J

2000-01-01

This fifth volume of the successful series Advances in Atomic Spectroscopy continues to discuss and investigate the area of atomic spectroscopy.It begins with a description of the use of various atomic spectroscopic methods and applications of speciation studies in atomic spectroscopy. The emphasis is on combining atomic spectroscopy with gas and liquid chromatography. In chapter two the authors describe new developments in tunable lasers and the impact they will have on atomic spectroscopy. The traditional methods of detection, such as photography and the photomultiplier, and how they are being replaced by new detectors is discussed in chapter three. The very active area of glow discharge atomic spectrometry is presented in chapter four where, after a brief introduction and historical review, the use of glow discharge lamps for atomic spectroscopy and mass spectrometry are discussed. Included in this discussion is geometry and radiofrequency power. The future of this source in atomic spectroscopy is also dis...

The Amsterdam Resting-State Questionnaire reveals multiple phenotypes of resting-state cognition

Directory of Open Access Journals (Sweden)

B. Alexander eDiaz

2013-08-01

Full Text Available Resting-state neuroimaging is a dominant paradigm for studying brain function in health and disease. It is attractive for clinical research because of its simplicity for patients, straightforward standardization, and sensitivity to brain disorders. Importantly, non-sensory experiences like mind wandering may arise from ongoing brain activity. However, little is known about the link between ongoing brain activity and cognition, as phenotypes of resting-state cognition—and tools to quantify them—have been lacking. To facilitate rapid and structured measurements of resting-state cognition we developed a 50-item self-report survey, the Amsterdam Resting-State Questionnaire (ARSQ. Based on ARSQ data from 813 participants assessed after five minutes eyes-closed rest in their home, we identified seven dimensions of resting-state cognition using factor analysis: Discontinuity of Mind, Theory of Mind, Self, Planning, Sleepiness, Comfort, and Somatic Awareness. Further, we showed that the structure of cognition was similar during resting-state fMRI and EEG, and that the test-retest correlations were remarkably high for all dimensions. To explore whether inter-individual variation of resting-state cognition is related to health status, we correlated ARSQ-derived factor scores with psychometric scales measuring depression, anxiety, and sleep quality. Mental health correlated positively with Comfort and negatively with Discontinuity of Mind. Finally, we show that sleepiness may partially explain a resting-state EEG profile previously associated with Alzheimer’s disease. These findings indicate that the ARSQ readily provides information about cognitive phenotypes and that it is a promising tool for research on the neural correlates of resting-state cognition in health and disease.

Towards relativistic atomic physics. Part 1. The rest-frame instant form of dynamics and a canonical transformation for a system of charged particles plus the electromagnetic field

International Nuclear Information System (INIS)

Alba, D.; Crater, H.W.; Lusanna, L.

2010-01-01

A complete exposition of the rest-frame instant form of dynamics for arbitrary isolated systems (particles, fields, strings, fluids) admitting a Lagrangian description is given. The starting point is the parametrized Minkowski theory describing the system in arbitrary admissible noninertial frames in Minkowski space-time, which allows one to define the energy-momentum tensor of the system and to show the independence of the description from the clock synchronization convention and from the choice of the 3-coordinates. The restriction to the inertial rest frame, centered on the inertial observer having the Fokker-Pryce center-of-inertia world-line, and the study of relativistic collective variables replacing the nonrelativistic center of mass lead to the description of the isolated system as a decoupled globally defined noncovariant canonical external center of mass carrying a pole-dipole structure (the invariant mass M and the rest spin S¯ of the system) and an external realization of the Poincare group. Mc and S¯ are the energy and angular momentum of a unfaithful internal realization of the Poincare group built with the energy-momentum tensor of the system and acting inside the instantaneous Wigner 3-spaces where all the 3-vectors are Wigner covariant. The vanishing of the internal 3-momentum and of the internal Lorentz boosts eliminate the internal 3-center of mass inside the Wigner 3-spaces, so that at the end the isolated system is described only by Wigner-covariant canonical internal relative variables. Then an isolated system of positive-energy charged scalar articles with mutual Coulomb interaction plus a transverse electromagnetic field in the radiation gauge is investigated as a classical background for defining relativistic atomic physics. The electric charges of the particles are Grassmann-valued to regularize the self-energies. The external and internal realizations of the Poincare algebra in the rest-frame instant form of dynamics are found. This

Evolution of the Contact Area with Normal Load for Rough Surfaces: from Atomic to Macroscopic Scales.

Science.gov (United States)

Huang, Shiping

2017-11-13

The evolution of the contact area with normal load for rough surfaces has great fundamental and practical importance, ranging from earthquake dynamics to machine wear. This work bridges the gap between the atomic scale and the macroscopic scale for normal contact behavior. The real contact area, which is formed by a large ensemble of discrete contacts (clusters), is proven to be much smaller than the apparent surface area. The distribution of the discrete contact clusters and the interaction between them are key to revealing the mechanism of the contacting solids. To this end, Green's function molecular dynamics (GFMD) is used to study both how the contact cluster evolves from the atomic scale to the macroscopic scale and the interaction between clusters. It is found that the interaction between clusters has a strong effect on their formation. The formation and distribution of the contact clusters is far more complicated than that predicted by the asperity model. Ignorance of the interaction between them leads to overestimating the contacting force. In real contact, contacting clusters are smaller and more discrete due to the interaction between the asperities. Understanding the exact nature of the contact area with the normal load is essential to the following research on friction.

Dispositional Mindfulness and Depressive Symptomatology: Correlations with Limbic and Self-Referential Neural Activity during Rest

Science.gov (United States)

Way, Baldwin M.; Creswell, J. David; Eisenberger, Naomi I.; Lieberman, Matthew D.

2010-01-01

To better understand the relationship between mindfulness and depression, we studied normal young adults (n=27) who completed measures of dispositional mindfulness and depressive symptomatology, which were then correlated with: a) Rest: resting neural activity during passive viewing of a fixation cross, relative to a simple goal-directed task (shape-matching); and b) Reactivity: neural reactivity during viewing of negative emotional faces, relative to the same shape-matching task. Dispositional mindfulness was negatively correlated with resting activity in self-referential processing areas, while depressive symptomatology was positively correlated with resting activity in similar areas. In addition, dispositional mindfulness was negatively correlated with resting activity in the amygdala, bilaterally, while depressive symptomatology was positively correlated with activity in the right amygdala. Similarly, when viewing emotional faces, amygdala reactivity was positively correlated with depressive symptomatology and negatively correlated with dispositional mindfulness, an effect that was largely attributable to differences in resting activity. These findings indicate that mindfulness is associated with intrinsic neural activity and that changes in resting amygdala activity could be a potential mechanism by which mindfulness-based depression treatments elicit therapeutic improvement. PMID:20141298

Advances in atomic spectroscopy

CERN Document Server

Sneddon, J

1997-01-01

This series describes selected advances in the area of atomic spectroscopy. It is primarily intended for the reader who has a background in atmoic spectroscopy; suitable to the novice and expert. Although a widely used and accepted method for metal and non-metal analysis in a variety of complex samples, Advances in Atomic Spectroscopy covers a wide range of materials. Each Chapter will completely cover an area of atomic spectroscopy where rapid development has occurred.

Resting state FMRI research in child psychiatric disorders

NARCIS (Netherlands)

Oldehinkel, Marianne; Francx, Winke; Beckmann, Christian; Buitelaar, Jan K.; Mennes, Maarten

2013-01-01

Concurring with the shift from linking functions to specific brain areas towards studying network integration, resting state FMRI (R-FMRI) has become an important tool for delineating the functional network architecture of the brain. Fueled by straightforward data collection, R-FMRI analysis methods

Stomach-brain synchrony reveals a novel, delayed-connectivity resting-state network in humans.

Science.gov (United States)

Rebollo, Ignacio; Devauchelle, Anne-Dominique; Béranger, Benoît; Tallon-Baudry, Catherine

2018-03-21

Resting-state networks offer a unique window into the brain's functional architecture, but their characterization remains limited to instantaneous connectivity thus far. Here, we describe a novel resting-state network based on the delayed connectivity between the brain and the slow electrical rhythm (0.05 Hz) generated in the stomach. The gastric network cuts across classical resting-state networks with partial overlap with autonomic regulation areas. This network is composed of regions with convergent functional properties involved in mapping bodily space through touch, action or vision, as well as mapping external space in bodily coordinates. The network is characterized by a precise temporal sequence of activations within a gastric cycle, beginning with somato-motor cortices and ending with the extrastriate body area and dorsal precuneus. Our results demonstrate that canonical resting-state networks based on instantaneous connectivity represent only one of the possible partitions of the brain into coherent networks based on temporal dynamics. © 2018, Rebollo et al.

Resting states are resting traits--an FMRI study of sex differences and menstrual cycle effects in resting state cognitive control networks.

Science.gov (United States)

Hjelmervik, Helene; Hausmann, Markus; Osnes, Berge; Westerhausen, René; Specht, Karsten

2014-01-01

To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the current study is particularly interested in fronto-parietal resting state networks. Resting state fMRI was measured in sixteen women during three different cycle phases (menstrual, follicular, and luteal). Fifteen men underwent three sessions in corresponding time intervals. We used independent component analysis to identify four fronto-parietal networks. The results showed sex differences in two of these networks with women exhibiting higher functional connectivity in general, including the prefrontal cortex. Menstrual cycle effects on resting states were non-existent. It is concluded that sex differences in resting state fMRI might reflect sexual dimorphisms in the brain rather than transitory activating effects of sex hormones on the functional connectivity in the resting brain.

Alternative REST Splicing Underappreciated

OpenAIRE

Chen, Guo-Lin; Miller, Gregory

2017-01-01

As a major orchestrator of the cellular epigenome, the repressor element-1 silencing transcription factor (REST) can either repress or activate thousands of genes depending on cellular context, suggesting a highly context-dependent REST function tuned by environmental cues. While REST shows cell-type non-selective active transcription, an N-terminal REST4 isoform caused by alternative splicing - inclusion of an extra exon (N3c) which introduces a pre-mature stop codon - has been implicated in...

Cross coherence independent component analysis in resting and action states EEG discrimination

International Nuclear Information System (INIS)

Almurshedi, A; Ismail, A K

2014-01-01

Cross Coherence time frequency transform and independent component analysis (ICA) method were used to analyse the electroencephalogram (EEG) signals in resting and action states during open and close eyes conditions. From the topographical scalp distributions of delta, theta, alpha, and beta power spectrum can clearly discriminate between the signal when the eyes were open or closed, but it was difficult to distinguish between resting and action states when the eyes were closed. In open eyes condition, the frontal area (Fp1, Fp2) was activated (higher power) in delta and theta bands whilst occipital (O1, O2) and partial (P3, P4, Pz) area of brain was activated alpha band in closed eyes condition. The cross coherence method of time frequency analysis is capable of discrimination between rest and action brain signals in closed eyes condition

Cognitive and default-mode resting state networks: do male and female brains "rest" differently?

Science.gov (United States)

Weissman-Fogel, Irit; Moayedi, Massieh; Taylor, Keri S; Pope, Geoff; Davis, Karen D

2010-11-01

Variability in human behavior related to sex is supported by neuroimaging studies showing differences in brain activation patterns during cognitive task performance. An emerging field is examining the human connectome, including networks of brain regions that are not only temporally-correlated during different task conditions, but also networks that show highly correlated spontaneous activity during a task-free state. Both task-related and task-free network activity has been associated with individual task performance and behavior under certain conditions. Therefore, our aim was to determine whether sex differences exist during a task-free resting state for two networks associated with cognitive task performance (executive control network (ECN), salience network (SN)) and the default mode network (DMN). Forty-nine healthy subjects (26 females, 23 males) underwent a 5-min task-free fMRI scan in a 3T MRI. An independent components analysis (ICA) was performed to identify the best-fit IC for each network based on specific spatial nodes defined in previous studies. To determine the consistency of these networks across subjects we performed self-organizing group-level ICA analyses. There were no significant differences between sexes in the functional connectivity of the brain areas within the ECN, SN, or the DMN. These important findings highlight the robustness of intrinsic connectivity of these resting state networks and their similarity between sexes. Furthermore, our findings suggest that resting state fMRI studies do not need to be controlled for sex. © 2010 Wiley-Liss, Inc.

Comparison of Ocular Outcomes in Two 14-Day Bed Rest Studies

Science.gov (United States)

Cromwell, R. L.; Zanello, S. B.; Yarbough, P. O.; Taibbi, G.; Vizzeri, G.

2011-01-01

Reports of astronauts visual changes raised concern about ocular health during long-duration spaceflight. Some of these findings included hyperopic shifts, choroidal folds, optic disc edema, retinal nerve fiber layer (RNFL) thickening, and cotton wool spots. While the etiology remains unknown, hypotheses speculate that hypertension in the brain caused by cephalad fluid shifts during spaceflight is a possible mechanism for these ocular changes. Head-down tilt (HDT) bed rest is a spaceflight analog that induces cephalad fluid shifts. In addition, previous studies of the HDT position demonstrated body fluid shifts associated with changes in intraocular pressure (IOP). For these reasons, vision monitoring of HDT bed rest subjects was implemented for NASA bed rest studies. Subjects selected for these studies were healthy adults (14 males and 5 females). Average age was 37.5 plus or minus 9.1 years, weight was 77.4 plus or minus 11.3 Kg, and height was 173.4 plus or minus 7.2 14 cm. Controlled conditions followed for all NASA bed rest studies were implemented. These conditions included factors such as eating a standardized diet, maintaining a strict sleep wake cycle, and remaining in bed for 24 hours each day. In one study, subjects maintained a horizontal (0 degree) position while in bed and were exercised six days per week with an integrated resistance and aerobic training (iRAT) program. In the other study, subjects were placed at 6 degrees HDT while in bed and did not engage in exercise. All subjects underwent pre- and post bed rest vision testing. While the battery of vision tests for each study was not identical, measures common to both studies will be presented. These measures included IOP and measures that provided an indication of optic disc swelling as derived from optical coherence tomography (OCT) testing: average retinal nerve fiber layer (RNFL) thickness (millimeters), disc area (square millimeters), rim area (square millimters), and average cup to disc (C

EMF-REST: Generation of RESTful APIs from Models

OpenAIRE

Hamza , Ed-Douibi; Cánovas Izquierdo , Javier Luis; Gómez , Abel; Tisi , Massimo; Cabot , Jordi

2016-01-01

In the last years, RESTful Web services have become more and more popular as a lightweight solution to connect remote systems in distributed and Cloud-based architectures. However, being an architectural style rather than a specification or standard, the proper design of RESTful Web services is not trivial since developers have to deal with a plethora of recommendations and best practices. Model-Driven Engineering (MDE) emphasizes the use of models and model transformations to raise the level...

Stress/Rest Tc-99m-MIBI SPECT in Comparison with Rest/Stress Rubidium - 82 PET

International Nuclear Information System (INIS)

Lee, D. S.; Kamg, K. W.; Lee, K. H.; Jeong, J. M.; Kwark, C. E.; Chung, J. K.; Lee, M.C.; Seo, J. D.; Koh, C. S.

1995-01-01

We compared stress/rest myocardial Tc-99m-MIBI tomographic image findings with rest/stress rubidium-82 tomographic images. In 23 patients with coronary artery disease (12 of them received bypass grafts before) and 6 normal subjects, rest rubidium PET study was performed, rubidium-82 and Tc-99m-MIBI were injected simultaneously to each patient after dipyridamole stress for rubidium PET and MIBI SPECT; and rest MIBI SPECT was performed 4 hours thereafter. We scored segmental decrease of rubidium, or MIBI uptakes into 5 grades for 29 segments from 3 short-axis, vertical and horizontal slices. Scores were summed for each major arterial territory. When more score than two grade-2's or one grade-3 was considered as the cue for significant stenosis for major arterial territories, 67% of 46 stenosed arteries were found with MIBI studies and 78% of them by rubidium studies. Fourteen among 28 grafted arterial territories of 12 post-CABG patients were found normal with both rubidium and MIBI. Segmental scores were concordant between rubidium and MIBI in 72% of 709-stress segments and in 80% of 825 rest segments. Stress rubidium segmental scores were less than stress MIBI scores in 9%, so were rest rubidium scores. Stress rubidium scores were more than stress MIBI scores in 20% of segments, and rest rubidium segmental scores were more than rest MIBI scores in 11%. Rank correlations (Spearman's rho's more than 0.7(stress) and 0.5(rest), slopes (MIBI/rubidium) around 0.7(stress) and 0.9(rest) suggested deeper and wider defects in stress with rubidium. Slope over 1 (MIBI/rubidium) with LAD segmental scores at rest and 7 territories which had much larger score with MIBI revealed exaggeration of rest defects with rest MIBI in same-day stress/rest study. Difference scores (stress-rest for each territory) suggesting ischemia were larger with rubidium (slope of MIBI/rubidium around 0.45). As has been implied by animal or separate-day- human studies, these segmental analyses with

Partial Correlation-Based Retinotopically Organized Resting-State Functional Connectivity Within and Between Areas of the Visual Cortex Reflects More Than Cortical Distance.

Science.gov (United States)

Dawson, Debra Ann; Lam, Jack; Lewis, Lindsay B; Carbonell, Felix; Mendola, Janine D; Shmuel, Amir

2016-02-01

Numerous studies have demonstrated functional magnetic resonance imaging (fMRI)-based resting-state functional connectivity (RSFC) between cortical areas. Recent evidence suggests that synchronous fluctuations in blood oxygenation level-dependent fMRI reflect functional organization at a scale finer than that of visual areas. In this study, we investigated whether RSFCs within and between lower visual areas are retinotopically organized and whether retinotopically organized RSFC merely reflects cortical distance. Subjects underwent retinotopic mapping and separately resting-state fMRI. Visual areas V1, V2, and V3, were subdivided into regions of interest (ROIs) according to quadrants and visual field eccentricity. Functional connectivity (FC) was computed based on Pearson's linear correlation (correlation), and Pearson's linear partial correlation (correlation between two time courses after the time courses from all other regions in the network are regressed out). Within a quadrant, within visual areas, all correlation and nearly all partial correlation FC measures showed statistical significance. Consistently in V1, V2, and to a lesser extent in V3, correlation decreased with increasing eccentricity separation. Consistent with previously reported monkey anatomical connectivity, correlation/partial correlation values between regions from adjacent areas (V1-V2 and V2-V3) were higher than those between nonadjacent areas (V1-V3). Within a quadrant, partial correlation showed consistent significance between regions from two different areas with the same or adjacent eccentricities. Pairs of ROIs with similar eccentricity showed higher correlation/partial correlation than pairs distant in eccentricity. Between dorsal and ventral quadrants, partial correlation between common and adjacent eccentricity regions within a visual area showed statistical significance; this extended to more distant eccentricity regions in V1. Within and between quadrants, correlation decreased

Lidar mapping of atmospheric atomic mercury in the Wanshan area, China.

Science.gov (United States)

Lian, Ming; Shang, Lihai; Duan, Zheng; Li, Yiyun; Zhao, Guangyu; Zhu, Shiming; Qiu, Guangle; Meng, Bo; Sommar, Jonas; Feng, Xinbin; Svanberg, Sune

2018-05-08

A novel mobile laser radar system was used for mapping gaseous atomic mercury (Hg 0 ) atmospheric pollution in the Wanshan district, south of Tongren City, Guizhou Province, China. This area is heavily impacted by legacy mercury from now abandoned mining activities. Differential absorption lidar measurements were supplemented by localized point monitoring using a Lumex RA-915M Zeeman modulation mercury analyzer. Range-resolved concentration measurements in different directions were performed. Concentrations in the lower atmospheric layers often exceeded levels of 100 ng/m 3 for March conditions with temperature ranging from 5 °C to 20 °C. A flux measurement of Hg 0 over a vertical cross section of 0.12 km 2 resulted in about 29 g/h. Vertical lidar sounding at night revealed quickly falling Hg 0 concentrations with height. This is the first lidar mapping demonstration in a heavily mercury-polluted area in China, illustrating the lidar potential in complementing point monitors. Copyright © 2018 Elsevier Ltd. All rights reserved.

Arbuscular mycorrhizal fungi associated with vegetation and soil parameters under rest grazing management in a desert steppe ecosystem.

Science.gov (United States)

Bai, Gegenbaoleer; Bao, Yuying; Du, Guoxin; Qi, Yunlong

2013-05-01

The impact of rest grazing on arbuscular mycorrhizal fungi (AMF) and the interactions of AMF with vegetation and soil parameters under rest grazing condition were investigated between spring and late summer in a desert steppe ecosystem with different grazing managements (rest grazing with different lengths of resting period, banned or continuous grazing) in Inner Mongolia, China. AMF diversity and colonization, vegetation biomass, soil properties and soil phosphatase activity were examined. In rest grazing areas of 60 days, AMF spore number and diversity index at a 0-10 cm soil depth as well as vesicular and hyphal colonization rates were higher compared with other grazing treatments. In addition, soil organic matter and total N contents were highest and soil alkaline phosphatase was most active under 60-day rest grazing. In August and September, these areas also had the highest amount of aboveground vegetation. The results indicated that resting grazing for an appropriate period of time in spring has a positive effect on AMF sporulation, colonization and diversity, and that under rest grazing conditions, AMF parameters are positively correlated with some soil characteristics.

Resting-State Connectivity Predicts Levodopa-Induced Dyskinesias in Parkinson's Disease

DEFF Research Database (Denmark)

Herz, Damian M.; Haagensen, Brian N.; Nielsen, Silas H.

2016-01-01

Background: Levodopa-induced dyskinesias are a common side effect of dopaminergic therapy in PD, but their neural correlates remain poorly understood. Objectives: This study examines whether dyskinesias are associated with abnormal dopaminergic modulation of resting-state cortico-striatal connect......Background: Levodopa-induced dyskinesias are a common side effect of dopaminergic therapy in PD, but their neural correlates remain poorly understood. Objectives: This study examines whether dyskinesias are associated with abnormal dopaminergic modulation of resting-state cortico......-striatal connectivity. Methods: Twelve PD patients with peak-of-dose dyskinesias and 12 patients without dyskinesias were withdrawn from dopaminergic medication. All patients received a single dose of fast-acting soluble levodopa and then underwent resting-state functional magnetic resonance imaging before any...... dyskinesias emerged. Levodopa-induced modulation of cortico-striatal resting-state connectivity was assessed between the putamen and the following 3 cortical regions of interest: supplementary motor area, primary sensorimotor cortex, and right inferior frontal gyrus. These functional connectivity measures...

Progress in atomic spectroscopy

International Nuclear Information System (INIS)

Beyer, H.J.; Kleinpoppen, H.

1984-01-01

This book presents reviews by leading experts in the field covering areas of research at the forefront of atomic spectroscopy. Topics considered include the k ordering of atomic structure, multiconfiguration Hartree-Fock calculations for complex atoms, new methods in high-resolution laser spectroscopy, resonance ionization spectroscopy (inert atom detection), trapped ion spectroscopy, high-magnetic-field atomic physics, the effects of magnetic and electric fields on highly excited atoms, x rays from superheavy collision systems, recoil ion spectroscopy with heavy ions, investigations of superheavy quasi-atoms via spectroscopy of electron rays and positrons, impact ionization by fast projectiles, and amplitudes and state parameters from ion- and atom-atom excitation processes

Resting-State Network Topology Differentiates Task Signals across the Adult Life Span.

Science.gov (United States)

Chan, Micaela Y; Alhazmi, Fahd H; Park, Denise C; Savalia, Neil K; Wig, Gagan S

2017-03-08

Brain network connectivity differs across individuals. For example, older adults exhibit less segregated resting-state subnetworks relative to younger adults (Chan et al., 2014). It has been hypothesized that individual differences in network connectivity impact the recruitment of brain areas during task execution. While recent studies have described the spatial overlap between resting-state functional correlation (RSFC) subnetworks and task-evoked activity, it is unclear whether individual variations in the connectivity pattern of a brain area (topology) relates to its activity during task execution. We report data from 238 cognitively normal participants (humans), sampled across the adult life span (20-89 years), to reveal that RSFC-based network organization systematically relates to the recruitment of brain areas across two functionally distinct tasks (visual and semantic). The functional activity of brain areas (network nodes) were characterized according to their patterns of RSFC: nodes with relatively greater connections to nodes in their own functional system ("non-connector" nodes) exhibited greater activity than nodes with relatively greater connections to nodes in other systems ("connector" nodes). This "activation selectivity" was specific to those brain systems that were central to each of the tasks. Increasing age was accompanied by less differentiated network topology and a corresponding reduction in activation selectivity (or differentiation) across relevant network nodes. The results provide evidence that connectional topology of brain areas quantified at rest relates to the functional activity of those areas during task. Based on these findings, we propose a novel network-based theory for previous reports of the "dedifferentiation" in brain activity observed in aging. SIGNIFICANCE STATEMENT Similar to other real-world networks, the organization of brain networks impacts their function. As brain network connectivity patterns differ across

Neural correlates of verbal creativity: Differences in resting-state functional connectivity associated with expertise in creative writing

Directory of Open Access Journals (Sweden)

Martin eLotze

2014-07-01

Full Text Available Neural characteristics of verbal creativity as assessed by word generation tasks have been recently identified, but differences in resting-state functional connectivity (rFC between experts and non-experts in creative writing have not been reported yet. Previous electroencephalography (EEG coherence measures during rest demonstrated a decreased cooperation between brain areas in association with creative thinking ability. Here, we used resting-state functional magnetic resonance imaging to compare 20 experts in creative writing and 23 age-matched non-experts with respect to rFC strengths within a brain network previously found to be associated with creative writing. Decreased rFC for experts was found between areas 44 of both hemispheres. Increased rFC for experts was observed between right hemispheric caudate and intraparietal sulcus. Correlation analysis of verbal creativity indices with rFC values in the expert group revealed predominantly negative associations, particularly of rFC between left area 44 and left temporal pole. Overall, our data support previous findings on reduced connectivity between interhemispheric areas and increased right-hemispheric connectivity during rest in highly verbally creative individuals.

Task vs. rest-different network configurations between the coactivation and the resting-state brain networks.

Science.gov (United States)

Di, Xin; Gohel, Suril; Kim, Eun H; Biswal, Bharat B

2013-01-01

There is a growing interest in studies of human brain networks using resting-state functional magnetic resonance imaging (fMRI). However, it is unclear whether and how brain networks measured during the resting-state exhibit comparable properties to brain networks during task performance. In the present study, we investigated meta-analytic coactivation patterns among brain regions based upon published neuroimaging studies, and compared the coactivation network configurations with those in the resting-state network. The strength of resting-state functional connectivity between two regions were strongly correlated with the coactivation strength. However, the coactivation network showed greater global efficiency, smaller mean clustering coefficient, and lower modularity compared with the resting-state network, which suggest a more efficient global information transmission and between system integrations during task performing. Hub shifts were also observed within the thalamus and the left inferior temporal cortex. The thalamus and the left inferior temporal cortex exhibited higher and lower degrees, respectively in the coactivation network compared with the resting-state network. These results shed light regarding the reconfiguration of the brain networks between task and resting-state conditions, and highlight the role of the thalamus in change of network configurations in task vs. rest.

Does an atom interferometer test the gravitational redshift at the Compton frequency?

International Nuclear Information System (INIS)

Wolf, Peter; Borde, Christian J; Blanchet, Luc; Reynaud, Serge; Salomon, Christophe; Cohen-Tannoudji, Claude

2011-01-01

Atom interferometers allow the measurement of the acceleration of freely falling atoms with respect to an experimental platform at rest on Earth's surface. Such experiments have been used to test the universality of free fall by comparing the acceleration of the atoms to that of a classical freely falling object. In a recent paper, Mueller et al (2010 Nature 463 926-9) argued that atom interferometers also provide a very accurate test of the gravitational redshift (or universality of clock rates). Considering the atom as a clock operating at the Compton frequency associated with the rest mass, they claimed that the interferometer measures the gravitational redshift between the atom-clocks in the two paths of the interferometer at different values of gravitational potentials. In this paper, we analyze this claim in the frame of general relativity and of different alternative theories. We show that the difference of 'Compton phases' between the two paths of the interferometer is actually zero in a large class of theories, including general relativity, all metric theories of gravity, most non-metric theories and most theoretical frameworks used to interpret the violations of the equivalence principle. Therefore, in most plausible theoretical frameworks, there is no redshift effect and atom interferometers only test the universality of free fall. We also show that frameworks in which atom interferometers would test the redshift pose serious problems, such as (i) violation of the Schiff conjecture, (ii) violation of the Feynman path integral formulation of quantum mechanics and of the principle of least action for matter waves, (iii) violation of energy conservation, and more generally (iv) violation of the particle-wave duality in quantum mechanics. Standard quantum mechanics is no longer valid in such frameworks, so that a consistent interpretation of the experiment would require an alternative formulation of quantum mechanics. As such an alternative has not been

Effects of Flotation-REST on Muscle Tension Pain

Directory of Open Access Journals (Sweden)

Anette Kjellgren

2001-01-01

Full Text Available The purpose of the present study was to investigate whether the floating form of the restricted environmental stimulation technique (REST may be applied within the field of pain relief. Flotation-REST consists of a procedure whereby an individual is immersed in a tank filled with water of an extremely high salt concentration. Thirty-seven patients (14 men and 23 women suffering from chronic pain consisting of aching muscles in the neck and back area participated in the study. They were randomly assigned to either a control group (17 participants or an experimental group (20 participants. The experimental group received nine opportunities to use the flotation-REST technique in the water tank over a three-week period. The results indicated that the most severe perceived pain intensity was significantly reduced, whereas low perceived pain intensity was not influenced by the floating technique. Further, the results indicated that circulating levels of the noradrenaline metabolite 3-methoxy-4-hydroxyphenylethyleneglycol were reduced significantly in the experimental group but not in the control group following treatment, whereas endorphin levels were not affected by flotation. Flotation-REST treatment also elevated the participants' optimism and reduced the degree of anxiety or depression; at nighttime, patients who underwent flotation fell asleep more easily. The present findings describe possible changes, for the better, in patients presenting with chronic pain complaints.

Effects of flotation-REST on muscle tension pain.

Science.gov (United States)

Kjellgren, A; Sundequist, U; Norlander, T; Archer, T

2001-01-01

The purpose of the present study was to investigate whether the floating form of the restricted environmental stimulation technique (REST) may be applied within the field of pain relief. Flotation-REST consists of a procedure whereby an individual is immersed in a tank filled with water of an extremely high salt concentration. Thirty-seven patients (14 men and 23 women) suffering from chronic pain consisting of aching muscles in the neck and back area participated in the study. They were randomly assigned to either a control group (17 participants) or an experimental group (20 participants). The experimental group received nine opportunities to use the flotation-REST technique in the water tank over a three-week period. The results indicated that the most severe perceived pain intensity was significantly reduced, whereas low perceived pain intensity was not influenced by the floating technique. Further, the results indicated that circulating levels of the noradrenaline metabolite 3-methoxy-4-hydroxyphenylethyleneglycol were reduced significantly in the experimental group but not in the control group following treatment, whereas endorphin levels were not affected by flotation. Flotation-REST treatment also elevated the participants' optimism and reduced the degree of anxiety or depression; at nighttime, patients who underwent flotation fell asleep more easily. The present findings describe possible changes, for the better, in patients presenting with chronic pain complaints.

Effect of ventilation rate on air cleanliness and energy consumption in operation rooms at rest.

Science.gov (United States)

Lee, Shih-Tseng; Liang, Ching-Chieh; Chien, Tsung-Yi; Wu, Feng-Jen; Fan, Kuang-Chung; Wan, Gwo-Hwa

2018-02-27

The interrelationships between ventilation rate, indoor air quality, and energy consumption in operation rooms at rest are yet to be understood. We investigate the effect of ventilation rate on indoor air quality indices and energy consumption in ORs at rest. The study investigates the air temperature, relative humidity, concentrations of carbon dioxide, particulate matter (PM), and airborne bacteria at different ventilation rates in operation rooms at rest of a medical center. The energy consumption and cost analysis of the heating, ventilating, and air conditioning (HVAC) system in the operation rooms at rest were also evaluated for all ventilation rates. No air-conditioned operation rooms had very highest PM and airborne bacterial concentrations in the operation areas. The bacterial concentration in the operation areas with 6-30 air changes per hour (ACH) was below the suggested level set by the United Kingdom (UK) for an empty operation room. A 70% of reduction in annual energy cost by reducing the ventilation rate from 30 to 6 ACH was found in the operation rooms at rest. Maintenance of operation rooms at ventilation rate of 6 ACH could save considerable amounts of energy and achieve the goal of air cleanliness.

Atomic Spectroscopy and Collisions Using Slow Antiprotons \\\\ ASACUSA Collaboration

CERN Multimedia

Matsuda, Y; Lodi-rizzini, E; Kuroda, N; Schettino, G; Hori, M; Pirkl, W; Mascagna, V; Leali, M; Malbrunot, C L S; Yamazaki, Y; Eades, J; Simon, M; Massiczek, O; Sauerzopf, C; Nagata, Y; Knudsen, H; Uggerhoj, U I; Mc cullough, R W; Toekesi, K M; Venturelli, L; Widmann, E; Zmeskal, J; Kanai, Y; Kristiansen, H; Todoroki, K; Bartel, M A; Moller, S P; Charlton, M; Diermaier, M; Kolbinger, B

2002-01-01

ASACUSA (\\underline{A}tomic \\underline{S}pectroscopy \\underline{A}nd \\underline{C}ollisions \\underline{U}sing \\underline{S}low \\underline{A}ntiprotons) is a collaboration between a number of Japanese and European research institutions, with the goal of studying bound and continuum states of antiprotons with simple atoms.\\\\ Three phases of experimentation are planned for ASACUSA. In the first phase, we use the direct $\\overline{p}$ beam from AD at 5.3 MeV and concentrate on the laser and microwave spectroscopy of the metastable antiprotonic helium atom, $\\overline{p}$He$^+$, consisting of an electron and antiproton bound by the Coulomb force to the helium nucleus. Samples of these are readily created by bringing AD antiproton beam bunches to rest in helium gas. With the help of techniques developed at LEAR for resonating high precision laser beams with antiproton transitions in these atoms, ASACUSA achieved several of these first-phase objectives during a few short months of AD operation in 2000. Six atomic tr...

Resting-state brain activity in the motor cortex reflects task-induced activity: A multi-voxel pattern analysis.

Science.gov (United States)

Kusano, Toshiki; Kurashige, Hiroki; Nambu, Isao; Moriguchi, Yoshiya; Hanakawa, Takashi; Wada, Yasuhiro; Osu, Rieko

2015-08-01

It has been suggested that resting-state brain activity reflects task-induced brain activity patterns. In this study, we examined whether neural representations of specific movements can be observed in the resting-state brain activity patterns of motor areas. First, we defined two regions of interest (ROIs) to examine brain activity associated with two different behavioral tasks. Using multi-voxel pattern analysis with regularized logistic regression, we designed a decoder to detect voxel-level neural representations corresponding to the tasks in each ROI. Next, we applied the decoder to resting-state brain activity. We found that the decoder discriminated resting-state neural activity with accuracy comparable to that associated with task-induced neural activity. The distribution of learned weighted parameters for each ROI was similar for resting-state and task-induced activities. Large weighted parameters were mainly located on conjunctive areas. Moreover, the accuracy of detection was higher than that for a decoder whose weights were randomly shuffled, indicating that the resting-state brain activity includes multi-voxel patterns similar to the neural representation for the tasks. Therefore, these results suggest that the neural representation of resting-state brain activity is more finely organized and more complex than conventionally considered.

Expression of REST4 in human gliomas in vivo and influence of pioglitazone on REST in vitro

Energy Technology Data Exchange (ETDEWEB)

Ren, Huan [Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008 (China); Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078 (China); Gao, Zhangfeng [Department of Neurosurgery, Second Xiangya Hospital of Central South University, Changsha 410008 (China); Wu, Nayiyuan; Zeng, Liu; Tang, Xinyue; Chen, Xiaoping; Liu, Zhaoqian; Zhang, Wei; Wang, Liansheng [Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008 (China); Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078 (China); Li, Zhi, E-mail: lizhi489@163.com [Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008 (China); Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078 (China)

2015-08-07

The repressor element-1 (RE1) silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) has an irreplaceable role during the differentiation of neurons. REST has multiple splice variants which link to various types of cancer. Previous work had highlighted the role of REST in glioma, where the expression of REST is enhanced. But whether alternative splicing of REST is expressed in glioma has not been described. Here, we show that a specific isoform REST4 is expressed in glioma specimens, and will influence the mRNA level of REST in vivo. Peroxisome proliferator-activated receptor-γ (PPARγ) agonists have a role of antineoplastic in various tumor cells, which including glioma cells. Moreover, study indicated that PPARγ agonist pioglitazone can promote alternative splicing of REST pre-mRNA. In this study, we selected pioglitazone as a tool drug to explore whether the role of pioglitazone in anti-glioma is mediated by regulating REST expression or promoting alternative splicing of REST in glioma cells. Results show that pioglitazone can inhibit proliferation and induce apoptosis of glioma cell in vitro, which may be mediated by down-regulating REST mRNA level but not by inducing alternative splicing of REST pre-mRNA. Our study firstly reports the expression of REST4 in glioma tissue samples. And we recommend that pioglitazone, which can reduce the expression level of REST, represents a promising drug for therapy of glioma. - Highlights: • A specific isoform REST4 is expressed in glioma specimens in vivo. • REST4 will influence the mRNA level of REST in vivo. • Pioglitazone can inhibit proliferation and induce apoptosis of glioma cells. • The role of pioglitazone in anti-glioma may be mediated by down-regulating REST.

Expression of REST4 in human gliomas in vivo and influence of pioglitazone on REST in vitro

International Nuclear Information System (INIS)

Ren, Huan; Gao, Zhangfeng; Wu, Nayiyuan; Zeng, Liu; Tang, Xinyue; Chen, Xiaoping; Liu, Zhaoqian; Zhang, Wei; Wang, Liansheng; Li, Zhi

2015-01-01

The repressor element-1 (RE1) silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) has an irreplaceable role during the differentiation of neurons. REST has multiple splice variants which link to various types of cancer. Previous work had highlighted the role of REST in glioma, where the expression of REST is enhanced. But whether alternative splicing of REST is expressed in glioma has not been described. Here, we show that a specific isoform REST4 is expressed in glioma specimens, and will influence the mRNA level of REST in vivo. Peroxisome proliferator-activated receptor-γ (PPARγ) agonists have a role of antineoplastic in various tumor cells, which including glioma cells. Moreover, study indicated that PPARγ agonist pioglitazone can promote alternative splicing of REST pre-mRNA. In this study, we selected pioglitazone as a tool drug to explore whether the role of pioglitazone in anti-glioma is mediated by regulating REST expression or promoting alternative splicing of REST in glioma cells. Results show that pioglitazone can inhibit proliferation and induce apoptosis of glioma cell in vitro, which may be mediated by down-regulating REST mRNA level but not by inducing alternative splicing of REST pre-mRNA. Our study firstly reports the expression of REST4 in glioma tissue samples. And we recommend that pioglitazone, which can reduce the expression level of REST, represents a promising drug for therapy of glioma. - Highlights: • A specific isoform REST4 is expressed in glioma specimens in vivo. • REST4 will influence the mRNA level of REST in vivo. • Pioglitazone can inhibit proliferation and induce apoptosis of glioma cells. • The role of pioglitazone in anti-glioma may be mediated by down-regulating REST

On the Debye-Waller factor in atom-surface scattering

International Nuclear Information System (INIS)

Garcia, N.; Maradudin, A.A.; Celli, V.

1982-01-01

A theory for the Debye-Waller factor in atom-surface scattering is presented, to lowest order in the phonon contributions. Multiple-scattering effects as well as the cross-correlated surface atom displacements are included. The theory accounts for experimental data without the necessity of introducing the Armand effect, which is due to the finite size of the incident atom. The work presented here implies that the Kirchhoff approximation fails when the energy of the incident particle is in the energy range of the phonon spectrum. The results of the calculation are presented in the high-temperature limit, and it is observed that the Rayleigh surface phonons contribute three-quarters of the Debye-Waller factor, while the bulk phonons account for the rest. This result is interesting because the calculation of the former contribution is simpler than that of the latter. (author)

RESTful Web Services Cookbook

CERN Document Server

Allamaraju, Subbu

2010-01-01

While the REST design philosophy has captured the imagination of web and enterprise developers alike, using this approach to develop real web services is no picnic. This cookbook includes more than 100 recipes to help you take advantage of REST, HTTP, and the infrastructure of the Web. You'll learn ways to design RESTful web services for client and server applications that meet performance, scalability, reliability, and security goals, no matter what programming language and development framework you use. Each recipe includes one or two problem statements, with easy-to-follow, step-by-step i

Resting state functional connectivity changes in adults with developmental stuttering: an initial sLORETA study.

Directory of Open Access Journals (Sweden)

Kathleen eJoos

2014-10-01

Full Text Available Introduction: Stuttering is defined as speech characterized by verbal dysfluencies, but should not be seen as an isolated speech disorder, but as a generalized sensorimotor timing deficit due to impaired communication between speech related brain areas. Therefore we focused on resting state brain activity and functional connectivity.Method: We included 11 patients with developmental stuttering and 11 age matched controls. To objectify stuttering severity and the impact on the quality of life (QoL, we used the Dutch validated Test for Stuttering Severity-Readers (TSS-R and the Overall Assessment of the Speaker’s Experience of Stuttering (OASES, respectively. Furthermore, we used standardized low resolution brain electromagnetic tomography (sLORETA analyses to look at resting state activity and functional connectivity differences and their correlations with the TSS-R and OASES.Results: No resting state activity differences were identified in comparison to fluently speaking controls or in correlation with stuttering severity or QoL measures. Significant alterations in resting state functional connectivity were found, predominantly interhemispheric, i.e. a decreased functional connectivity for high frequency oscillations (beta and gamma between motor speech areas (BA44 and 45 and the contralateral premotor (BA 6 and motor (BA 4 areas. A positive correlation was found between functional connectivity at low frequency oscillations (theta and alpha and stuttering severity, while a mixed increased and decreased functional connectivity at low and high frequency oscillations correlated with QoL.Discussion: PWS are characterized by decreased high frequency interhemispheric functional connectivity between motor speech, premotor and motor areas in the resting state, while higher functional connectivity in the low frequency bands indicates more severe speech disturbances, suggesting that increased interhemispheric and right sided functional connectivity is

Changes in resting-state fMRI in vestibular neuritis.

Science.gov (United States)

Helmchen, Christoph; Ye, Zheng; Sprenger, Andreas; Münte, Thomas F

2014-11-01

responsiveness, postural sway). VN leads to a change in resting-state activity of the contralateral IPS adjacent to the SMG, which reverses during vestibular compensation over 3 months. The ventral intraparietal area in the IPS contains multimodal regions with directionally selective responses to vestibular stimuli making them suitable for participating in spatial orientation and multisensory integration. The clinical importance is indicated by the fact that the increase in resting-state activity tended to be larger in those patients with only little disability at the follow-up examination. This may indicate powerful restitution-related or compensatory cortical changes in resting-state activity.

Current Trends in Atomic Spectroscopy.

Science.gov (United States)

Wynne, James J.

1983-01-01

Atomic spectroscopy is the study of atoms/ions through their interaction with electromagnetic radiation, in particular, interactions in which radiation is absorbed or emitted with an internal rearrangement of the atom's electrons. Discusses nature of this field, its status and future, and how it is applied to other areas of physics. (JN)

Comparison of stress-rest and rest-stress one day myocardial perfusion scintigraphies in detecting coronary artery diseases

International Nuclear Information System (INIS)

Bom, Hee Seung; Min, Jung Jun; Song, Ho Cheon; Kim, Ji Yeul

1997-01-01

It has been shown that both rest and stress myocardial perfusion imaging with technetium agents can be performed on the same day using two different doses injected within few hours. The purpose of this study was to compare the two protocols (stress-rest and rest-stress) in detecting coronary artery diseases. One hundred and sixty patients (101 males, 59 females, mean age 57±9 years) and 120 patients (79 males, 41 females, mean age 59±10 years) underwent stress-rest myocardial perfusion SPECT and rest-stress myocardial perfusion SPECT, respectively. All of them underwent both myocardial perfusion SPECT and coronary angiography within 1 month. A coronary stenosis was considered significant when it compromised the luminal diameter by ≥50%. The chi square test was used to compare differences in sensitivity, specificity and accuracy between the two groups. The overall sensitivity, specificity and accuracy of stress-rest protocol were 99%, 35% and 68%, respectively. Those of rest-stress protocol were 96%, 47% and 78%, respectively. There was no difference between the two protocols in identifying individual diseased coronary artery branches. Therefore, one day stress-rest and rest-stress myocardial SPECT using 99m Tc agents were comparable and were very sensitive tests in detecting coronary artery diseases

Modern atomic physics

CERN Document Server

Natarajan, Vasant

2015-01-01

Much of our understanding of physics in the last 30-plus years has come from research on atoms, photons, and their interactions. Collecting information previously scattered throughout the literature, Modern Atomic Physics provides students with one unified guide to contemporary developments in the field. After reviewing metrology and preliminary material, the text explains core areas of atomic physics. Important topics discussed include the spontaneous emission of radiation, stimulated transitions and the properties of gas, the physics and applications of resonance fluorescence, coherence, cooling and trapping of charged and neutral particles, and atomic beam magnetic resonance experiments. Covering standards, a different way of looking at a photon, stimulated radiation, and frequency combs, the appendices avoid jargon and use historical notes and personal anecdotes to make the topics accessible to non-atomic physics students. Written by a leader in atomic and optical physics, this text gives a state-of-the...

Atomic size effect on critical cooling rate and glass formation

International Nuclear Information System (INIS)

Jalali, Payman; Li Mo

2005-01-01

Atomic size effect on critical cooling rate and glass formability in a model binary system is investigated using molecular dynamics simulation. To isolate atomic size effect from the rest of the factors that critically influence the glass formation, a hard sphere model is employed in conjunction with a newly developed densification method. The glass formability is defined as a set of optimal conditions that result in the slowest cooling rate of the glass-forming liquid. Critical cooling rates are identified from extensive molecular dynamics simulations. A kinetic glass-forming diagram is mapped out that marks the boundary between the glass-forming regions and competing crystalline phases in terms of the parameters of the atomic size ratio and alloy concentration. It is found that the potency of the atomic size difference on glass formation is influenced greatly by the competing metastable and equilibrium crystalline phases in the system, and the kinetic processes leading to the formation of these phases. The mechanisms of the atomic size effect on topological instability of crystal packing and glass formation are discussed

Atomic and molecular manipulation

CERN Document Server

Mayne, Andrew J

2011-01-01

Work with individual atoms and molecules aims to demonstrate that miniaturized electronic, optical, magnetic, and mechanical devices can operate ultimately even at the level of a single atom or molecule. As such, atomic and molecular manipulation has played an emblematic role in the development of the field of nanoscience. New methods based on the use of the scanning tunnelling microscope (STM) have been developed to characterize and manipulate all the degrees of freedom of individual atoms and molecules with an unprecedented precision. In the meantime, new concepts have emerged to design molecules and substrates having specific optical, mechanical and electronic functions, thus opening the way to the fabrication of real nano-machines. Manipulation of individual atoms and molecules has also opened up completely new areas of research and knowledge, raising fundamental questions of "Optics at the atomic scale", "Mechanics at the atomic scale", Electronics at the atomic scale", "Quantum physics at the atomic sca...

Age-related differences in the response of leg muscle cross-sectional area and water diffusivity measures to a period of supine rest.

Science.gov (United States)

Lorbergs, Amanda L; Noseworthy, Michael D; MacIntyre, Norma J

2015-06-01

The object was to assess whether cross-sectional area (CSA) and water diffusion properties of leg muscles in young and older women change with increased time spent in supine rest. Healthy young (n = 9, aged 20-30 years) and older (n = 9, aged 65-75 years) women underwent MRI scanning of the right leg at baseline, 30 and 60 min of supine rest. Muscle CSA was derived from proton density images. Water diffusion properties [apparent diffusion coefficient (ADC) and fractional anisotropy (FA)] of the tibialis anterior and posterior, soleus, and medial and lateral heads of the gastrocnemius were derived from diffusion tensor imaging (DTI). Repeated measures ANOVAs and Bonferroni post hoc tests determined the effects of time and group on each muscle outcome. In both groups, muscle CSA and FA did not significantly change over time, whereas ADC significantly decreased. A greater decline at 30 min for young women was only observed for ADC in the medial gastrocnemius. Regardless of age, ADC values decreased with fluid shift associated with time spent supine, whereas CSA and FA were not affected. For leg muscle assessment in young and older women, DTI scanning protocols should consider the amount of time spent in a recumbent position.

Brain activation and inhibition after acupuncture at Taichong and Taixi: resting-state functional magnetic resonance imaging.

Science.gov (United States)

Zhang, Shao-Qun; Wang, Yan-Jie; Zhang, Ji-Ping; Chen, Jun-Qi; Wu, Chun-Xiao; Li, Zhi-Peng; Chen, Jia-Rong; Ouyang, Huai-Liang; Huang, Yong; Tang, Chun-Zhi

2015-02-01

Acupuncture can induce changes in the brain. However, the majority of studies to date have focused on a single acupoint at a time. In the present study, we observed activity changes in the brains of healthy volunteers before and after acupuncture at Taichong (LR3) and Taixi (KI3) using resting-state functional magnetic resonance imaging. Fifteen healthy volunteers underwent resting-state functional magnetic resonance imaging of the brain 15 minutes before acupuncture, then received acupuncture at Taichong and Taixi using the nail-pressing needle insertion method, after which the needle was retained in place for 30 minutes. Fifteen minutes after withdrawal of the needle, the volunteers underwent a further session of resting-state functional magnetic resonance imaging, which revealed that the amplitude of low-frequency fluctuation, a measure of spontaneous neuronal activity, increased mainly in the cerebral occipital lobe and middle occipital gyrus (Brodmann area 18/19), inferior occipital gyrus (Brodmann area 18) and cuneus (Brodmann area 18), but decreased mainly in the gyrus rectus of the frontal lobe (Brodmann area 11), inferior frontal gyrus (Brodmann area 44) and the center of the posterior lobe of the cerebellum. The present findings indicate that acupuncture at Taichong and Taixi specifically promote blood flow and activation in the brain areas related to vision, emotion and cognition, and inhibit brain areas related to emotion, attention, phonological and semantic processing, and memory.

Assessment of productivity and water use efficiency in three maize (zea mays L.) varieties in Kwabenya-Atomic area

International Nuclear Information System (INIS)

Frimpong, J. O.

2010-06-01

The production of rain-fed maize in the Kwabenya-Atomic area of the coastal savannah environment of Ghana is limited by low and erratic rainfall. Enhancing maize production in the area will require the use of maize varieties efficient in the use of soil moisture. The study was, therefore, conducted to evaluate three recently released maize varieties (Obatanpa, Mamaba, and Golden Crystal) for their efficiency in the use of soil moisture for total dry matter and grain production and consequently identify the maize varieties suitable for rain-fed production in the Kwabenya-Atomic area. Field experiments were conducted m 2008 during the major and minor cropping seasons at Kwabenya-Atomic area in Ghana using three maize varieties grown at a planting distance of 0.4 m within rows and 0.8 m between rows. The experimental design used was the randomised complete block design in four replicates. Plants were sampled every two weeks throughout the maize growing seasons. Access tubes installed in each sub-plot facilitated simultaneous moisture monitoring with the aid of a neutron probe (CPN (R) 503 Hydroprobe) in a 120 cm soil profile. The moisture content values were used for the estimation of actual evapotranspiration of the maize crop using the water balance approach. Grain yield (GY) and its associated water use efficiency (WUE GY ) were significantly different (P ≤ 0.05) among the maize varieties during the major cropping season with Mamaba producing the highest grain yield of 7250.0 kg ha -1 and WUE GY of 13.2 kg ha -1 mm -1 . For the minor cropping season, no significant difference was observed in grain yield, which ranged between 5800.0 and 7200.0 kg ha -1 , with Obatanpa producing the highest grain yield. No significant difference was observed in WUE GY during the minor cropping season which ranged between 14.6 and 19.1 kg ha -1 mm -1 with Obatanpa having the highest WUE GY . The maize genotype produced similar total dry matter (TDM) during each of the cropping

AgNOR Count in Resting Cells (Resting NOR Is a New Prognostic Marker in Invasive Bladder Tumor

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Mitsuro Tomobe

2001-01-01

Full Text Available Purpose: We have previously demonstrated that the AgNOR count in proliferating cells is a predictor of tumor recurrence in superficial bladder tumor (J. Urol. 162 (1999, 63–68. In the present study, we evaluate the type of AgNOR associated with cell cycles as a prognostic factor in invasive bladder tumor using a double staining technique employing both AgNOR and MIB-1 labelling. Materials and methods: Forty-four paraffin sections of invasive bladder tumors were stained simultaneously with AgNOR and MIB-1. The number of AgNORs in proliferating (MIB-1 positive or resting (MIB-1 negative cells were counted from a total of 100 nuclei. Correlations between MIB-1 associated AgNOR count and clinicopathological parameters were statistically analyzed. Results: The AgNOR count in proliferating cells (proliferating NOR was significantly higher than that in resting cells (resting NOR (p < 0.01. The resting NOR in tumors with distant metastases was significantly higher than that in tumors without metastases (p < 0.05. Patients with a low resting NOR tumor had a better prognosis than those with a high resting NOR tumor, whereas the proliferating NOR was not associated with survival. Survival analysis revealed that the resting NOR was the most powerful prognostic marker in patients with invasive bladder tumor (p < 0.05. Conclusions: Resting NOR had a predictive value in the prognosis of patients with invasive bladder tumor. Keywords: Transitional cell carcinoma, invasive, resting cell, AgNORs, MIB-1

Theoretical atomic physics for fusion: 1988 annual report

International Nuclear Information System (INIS)

Pindzola, M.S.

1988-01-01

This paper discusses progress in atomic physics in the following areas: Electron-impact ionization of atomic ions; electron-impact excitation of atomic ions; Dielectronic recombination of atomic ions; and relativistic effects on electron-ion scattering

CVD synthesis of large-area, highly crystalline MoSe2 atomic layers on diverse substrates and application to photodetectors.

Science.gov (United States)

Xia, Jing; Huang, Xing; Liu, Ling-Zhi; Wang, Meng; Wang, Lei; Huang, Ben; Zhu, Dan-Dan; Li, Jun-Jie; Gu, Chang-Zhi; Meng, Xiang-Min

2014-08-07

Synthesis of large-area, atomically thin transition metal dichalcogenides (TMDs) on diverse substrates is of central importance for the large-scale fabrication of flexible devices and heterojunction-based devices. In this work, we successfully synthesized a large area of highly-crystalline MoSe2 atomic layers on SiO2/Si, mica and Si substrates using a simple chemical vapour deposition (CVD) method at atmospheric pressure. Atomic force microscopy (AFM) and Raman spectroscopy reveal that the as-grown ultrathin MoSe2 layers change from a single layer to a few layers. Photoluminescence (PL) spectroscopy demonstrates that while the multi-layer MoSe2 shows weak emission peaks, the monolayer has a much stronger emission peak at ∼ 1.56 eV, indicating the transition from an indirect to a direct bandgap. Transmission electron microscopy (TEM) analysis confirms the single-crystallinity of MoSe2 layers with a hexagonal structure. In addition, the photoresponse performance of photodetectors based on MoSe2 monolayer was studied for the first time. The devices exhibit a rapid response of ∼ 60 ms and a good photoresponsivity of ∼ 13 mA/W (using a 532 nm laser at an intensity of 1 mW mm(-2) and a bias of 10 V), suggesting that MoSe2 monolayer is a promising material for photodetection applications.

The Effects of Long Duration Bed Rest on Functional Mobility and Balance: Relationship to Resting State Motor Cortex Connectivity

Science.gov (United States)

Erdeniz, B.; Koppelmans, V.; Bloomberg, J. J.; Kofman, I. S.; DeDios, Y. E.; Riascos-Castaneda, R. F.; Wood, S. J.; Mulavara, A. P.; Seidler, R. D.

2014-01-01

NASA offers researchers from a variety of backgrounds the opportunity to study bed rest as an experimental analog for space flight. Extended exposure to a head-down tilt position during long duration bed rest can resemble many of the effects of a low-gravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The aim of our study is to a) identify changes in brain function that occur with prolonged bed rest and characterize their recovery time course; b) assess whether and how these changes impact behavioral and neurocognitive performance. Thus far, we completed data collection from six participants that include task based and resting state fMRI. The data have been acquired through the bed rest facility located at the University of Texas Medical Branch (Galveston, TX). Subjects remained in bed with their heads tilted down 6 degrees below their feet for 70 consecutive days. Behavioral measures and neuroimaging assessments were obtained at seven time points: a) 7 and 12 days before bed rest; b) 7, 30, and 65 days during bed rest; and c) 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (FcMRI) analysis was performed to assess the connectivity of motor cortex in and out of bed rest. We found a decrease in motor cortex connectivity with vestibular cortex and the cerebellum from pre bed rest to in bed rest. We also used a battery of behavioral measures including the functional mobility test and computerized dynamic posturography collected before and after bed rest. We will report the preliminary results of analyses relating brain and behavior changes. Furthermore, we will also report the preliminary results of a spatial working memory task and vestibular stimulation during in and out of bed rest.

Microdissecting the Genetic Events in Nephrogenic Rests and Wilms’ Tumor Development

Science.gov (United States)

Charles, Adrian K.; Brown, Keith W.; Berry, P. Jeremy

1998-01-01

Nephrogenic rests are precursor lesions associated with about 40% of Wilms’ tumors. This study identifies genetic steps occurring in the development of Wilms’ tumor. Thirty-four Wilms’ tumors with nephrogenic rests and/or areas of anaplasia were microdissected from paraffin sections to determine whether and at what stage loss of heterozygosity (LOH) occurred, using polymerase chain reaction-based polymorphic markers at 11p13, 11p15, and 16q. LOH at these loci have been identified in Wilms’ tumors and are associated with identified or putative tumor suppressor genes. Three cystic nephromas/cystic partially differentiated nephroblastomas were also examined. LOH was detected in six cases at 11p13 and in six cases at 11p15, and two of these cases had LOH at both loci. All intralobar rests showing LOH also showed LOH in the tumor. A case with a small perilobar rest showed LOH of 11p13 only in the tumor. Five cases showing LOH at 16q were identified (this was identified only in the tumor, and not in the associated rest), and three of these had recurrence of the tumor. Two cases had a WT1 mutation (one germline and the other somatic), as well as LOH in both the intralobar rest and the tumor. A cystic partially differentiated nephroblastoma showed loss at 11p13 and 11p15, as well as at 16q. This study suggests that LOH at 11p13 and 11p15 and WT1 mutations are early events but that LOH at 16q occurs late in the pathogenesis of Wilms’ tumor. Intralobar and perilobar nephrogenic rests are known to have different biological behaviors, and this study suggests that they are genetically different. A multistep model of Wilms’ tumor pathogenesis is supported by these findings. PMID:9736048

Systemic inflammation and resting state connectivity of the default mode network.

Science.gov (United States)

Marsland, Anna L; Kuan, Dora C-H; Sheu, Lei K; Krajina, Katarina; Kraynak, Thomas E; Manuck, Stephen B; Gianaros, Peter J

2017-05-01

The default mode network (DMN) encompasses brain systems that exhibit coherent neural activity at rest. DMN brain systems have been implicated in diverse social, cognitive, and affective processes, as well as risk for forms of dementia and psychiatric disorders that associate with systemic inflammation. Areas of the anterior cingulate cortex (ACC) and surrounding medial prefrontal cortex (mPFC) within the DMN have been implicated specifically in regulating autonomic and neuroendocrine processes that relate to systemic inflammation via bidirectional signaling mechanisms. However, it is still unclear whether indicators of inflammation relate directly to coherent resting state activity of the ACC, mPFC, or other areas within the DMN. Accordingly, we tested whether plasma interleukin (IL)-6, an indicator of systemic inflammation, covaried with resting-state functional connectivity of the DMN among 98 adults aged 30-54 (39% male; 81% Caucasian). Independent component analyses were applied to resting state fMRI data to generate DMN connectivity maps. Voxel-wise regression analyses were then used to test for associations between IL-6 and DMN connectivity across individuals, controlling for age, sex, body mass index, and fMRI signal motion. Within the DMN, IL-6 covaried positively with connectivity of the sub-genual ACC and negatively with a region of the dorsal medial PFC at corrected statistical thresholds. These novel findings offer evidence for a unique association between a marker of systemic inflammation (IL-6) and ACC and mPFC functional connectivity within the DMN, a network that may be important for linking aspects of immune function to psychological and behavioral states in health and disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Abnormal resting state corticolimbic blood flow in depressed unmedicated patients with major depression: a (15)O-H(2)O PET study.

Science.gov (United States)

Monkul, E Serap; Silva, Leandro A P; Narayana, Shalini; Peluso, Marco A M; Zamarripa, Frank; Nery, Fabiano G; Najt, Pablo; Li, John; Lancaster, Jack L; Fox, Peter T; Lafer, Beny; Soares, Jair C

2012-02-01

We investigated the differences in the resting state corticolimbic blood flow between 20 unmedicated depressed patients and 21 healthy comparisons. Resting state cerebral blood flow (CBF) was measured with H(2)(15)O PET. Anatomical MRI scans were performed on an Elscint 1.9 T Prestige system for PET-MRI coregistration. Significant changes in cerebral blood flow indicating neural activity were detected using an ROI-free image subtraction strategy. In addition, the resting blood flow in patients was correlated with the severity of depression as measured by HAM-D scores. Depressed patients showed decreases in blood flow in right anterior cingulate (Brodmann areas 24 and 32) and increased blood flow in left and right posterior cingulate (Brodmann areas 23, 29, 30), left parahippocampal gyrus (Brodmann area 36), and right caudate compared with healthy volunteers. The severity of depression was inversely correlated with the left middle and inferior frontal gyri (Brodmann areas 9 and 47) and right medial frontal gyrus (Brodmann area 10) and right anterior cingulate (Brodmann areas 24, 32) blood flow, and directly correlated with the right thalamus blood flow. These findings support previous reports of abnormalities in the resting state blood flow in the limbic-frontal structures in depressed patients compared to healthy volunteers. Copyright © 2011 Wiley Periodicals, Inc.

Dirac Matrices and Feynman’s Rest of the Universe

Directory of Open Access Journals (Sweden)

Young S. Kim

2012-10-01

Full Text Available There are two sets of four-by-four matrices introduced by Dirac. The first set consists of fifteen Majorana matrices derivable from his four γ matrices. These fifteen matrices can also serve as the generators of the group SL(4, r. The second set consists of ten generators of the Sp(4 group which Dirac derived from two coupled harmonic oscillators. It is shown possible to extend the symmetry of Sp(4 to that of SL(4, r if the area of the phase space of one of the oscillators is allowed to become smaller without a lower limit. While there are no restrictions on the size of phase space in classical mechanics, Feynman’s rest of the universe makes this Sp(4-to-SL(4, r transition possible. The ten generators are for the world where quantum mechanics is valid. The remaining five generators belong to the rest of the universe. It is noted that the groups SL(4, r and Sp(4 are locally isomorphic to the Lorentz groups O(3, 3 and O(3, 2 respectively. This allows us to interpret Feynman’s rest of the universe in terms of space-time symmetry.

Flame emission, atomic absorption and fluorescence spectrometry

International Nuclear Information System (INIS)

Horlick, G.

1980-01-01

Six hundred and thirty references are cited in this review. The information in the review is divided into 12 major areas: books, reviews, and bibliographies; fundamental studies in flames; developments in instrumentation; measurement techniques and procedure; flame emission spectrometry; flame atomic absorption spectrometry; flame molecular absorption spectrometry; electrothermal atomization atomic absorption spectroscopy; hydride generation techniques; graphite furnace atomic emission spectrometry; atomic fluorescence spectrometry; and analytical comparisons

Brain activation and inhibition after acupuncture at Taichong and Taixi: resting-state functional magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Shao-qun Zhang

2015-01-01

Full Text Available Acupuncture can induce changes in the brain. However, the majority of studies to date have focused on a single acupoint at a time. In the present study, we observed activity changes in the brains of healthy volunteers before and after acupuncture at Taichong (LR3 and Taixi (KI3 using resting-state functional magnetic resonance imaging. Fifteen healthy volunteers underwent resting-state functional magnetic resonance imaging of the brain 15 minutes before acupuncture, then received acupuncture at Taichong and Taixi using the nail-pressing needle insertion method, after which the needle was retained in place for 30 minutes. Fifteen minutes after withdrawal of the needle, the volunteers underwent a further session of resting-state functional magnetic resonance imaging, which revealed that the amplitude of low-frequency fluctuation, a measure of spontaneous neuronal activity, increased mainly in the cerebral occipital lobe and middle occipital gyrus (Brodmann area 18/19, inferior occipital gyrus (Brodmann area 18 and cuneus (Brodmann area 18, but decreased mainly in the gyrus rectus of the frontal lobe (Brodmann area 11, inferior frontal gyrus (Brodmann area 44 and the center of the posterior lobe of the cerebellum. The present findings indicate that acupuncture at Taichong and Taixi specifically promote blood flow and activation in the brain areas related to vision, emotion and cognition, and inhibit brain areas related to emotion, attention, phonological and semantic processing, and memory.

Collapse and revival of the Doppler-Rabi oscillations of a moving atom in a cavity

International Nuclear Information System (INIS)

Kozlovskii, A. V.

2008-01-01

Collapse and revival of the Doppler-Rabi oscillations of a two-level atom moving in a cavity electromagnetic field are analyzed. The coupled atom-field dynamics are predicted accurately by numerical calculation and approximately by using the stationary phase approximation combined with the Poisson summation formula. The collapse and revival patterns are shown to be qualitatively different in the cases of moving atom and atom at rest. In particular, quantum revivals of Doppler-Rabi oscillations occur with a period determined by the Doppler shift of the atomic transition frequency. This regime of Doppler-Rabi oscillations requires that the Rabi frequency and the Doppler shift satisfy the condition Ω R D . Under the inverse relation, the collapse- revival phenomenon generally does not occur. It is shown that even a small amount of atom-cavity detuning eliminates collapse-revival behavior. The analysis is performed for both coherent and thermal cavity fields

The Effects of Long Duration Bed Rest on Brain Functional Connectivity and Sensorimotor Functioning

Science.gov (United States)

Cassady, K.; Koppelmans, V.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; Castenada, R. Riascos; Kofman, I.;

Improved limit on the electron anti neutrino rest mass from tritium β decay

International Nuclear Information System (INIS)

Weinheimer, C.; Przyrembel, M.; Backe, H.; Barth, H.; Bonn, J.; Degen, B.; Edling, T.; Fischer, H.; Fleischmann, L.; Grooss, J.U.; Haid, R.; Hermanni, A.; Kube, G.; Loeken, T.; Molz, A.; Osipowicz, A.; Otten, E.W.; Picard, A.; Schrader, M.; Steininger, M.

1993-01-01

This paper presents the results of a re-measurement of the endpoint region of the beta-spectrum of tritium by an electrostatic spectrometer with magnetic guiding field. It enables the search for a rest mass of the electron anti neutrino with improved precision. The result is: m ν 2 =(-39±34 stat ±15 syst ) (eV/c 2 ) 2 , from which an upper limit of: m ν 2 may be derived. The experiment yields the atomic mass difference: m(T)-m( 3 He)=(18591±3) eV/c 2 . (TEC). 31 refs., 4 figs., 3 tabs

Past, present, and possible future limits on the photon rest mass

International Nuclear Information System (INIS)

Nieto, M.M.

1992-01-01

In an historical context, present limits on the photon rest mass are reviewed. More stringent, yet speculative, limits which have been proposed are mentioned. Finally, new theoretical ideas and possible experimental improvements on the present limits are discussed, along with possible relationships between these two areas

Clinical physiology of bed rest

Science.gov (United States)

Greenleaf, John E.

1993-01-01

Maintenance of optimal health in humans requires the proper balance between exercise, rest, and sleep as well as time in the upright position. About one-third of a lifetime is spent sleeping; and it is no coincidence that sleeping is performed in the horizontal position, the position in which gravitational influence on the body is minimal. Although enforced bed rest is necessary for the treatment of some ailments, in some cases it has probably been used unwisely. In addition to the lower hydrostatic pressure with the normally dependent regions of the cardiovascular system, body fuid compartments during bed rest in the horizontal body position, and virtual elimination of compression on the long bones of the skeletal system during bed rest (hypogravia), there is often reduction in energy metabolism due to the relative confinement (hypodynamia) and alteration of ambulatory circadian variations in metabolism, body temperature, and many hormonal systems. If patients are also moved to unfamiliar surroundings, they probably experience some feelings of anxiety and some sociopsychological problems. Adaptive physiological responses during bed rest are normal for that environment. They are attempts by the body to reduce unnecessary energy expenditure, to optimize its function, and to enhance its survival potential. Many of the deconditioning responses begin within the first day or two of bed rest; these early responses have prompted physicians to insist upon early resumption of the upright posture and ambulation of bedridden patients.

Clustering of resting state networks.

Directory of Open Access Journals (Sweden)

Megan H Lee

Full Text Available The goal of the study was to demonstrate a hierarchical structure of resting state activity in the healthy brain using a data-driven clustering algorithm.The fuzzy-c-means clustering algorithm was applied to resting state fMRI data in cortical and subcortical gray matter from two groups acquired separately, one of 17 healthy individuals and the second of 21 healthy individuals. Different numbers of clusters and different starting conditions were used. A cluster dispersion measure determined the optimal numbers of clusters. An inner product metric provided a measure of similarity between different clusters. The two cluster result found the task-negative and task-positive systems. The cluster dispersion measure was minimized with seven and eleven clusters. Each of the clusters in the seven and eleven cluster result was associated with either the task-negative or task-positive system. Applying the algorithm to find seven clusters recovered previously described resting state networks, including the default mode network, frontoparietal control network, ventral and dorsal attention networks, somatomotor, visual, and language networks. The language and ventral attention networks had significant subcortical involvement. This parcellation was consistently found in a large majority of algorithm runs under different conditions and was robust to different methods of initialization.The clustering of resting state activity using different optimal numbers of clusters identified resting state networks comparable to previously obtained results. This work reinforces the observation that resting state networks are hierarchically organized.

Pro REST API development with nodejs

CERN Document Server

Doglio, Fernando

2015-01-01

Pro REST API Development with Node.js is your guide to managing and understanding the full capabilities of successful REST development. API design is a hot topic in the programming world, but not many resources exist for developers to really understand how you can leverage the advantages. This book will provide a brief background on REST and the tools it provides (well known and not so well known). Understand how there is more to REST than just JSON and URLs. You will then cover and compare the maintained modules currently available in the npm community, including Express, Restify, Vatican,

Quantum mechanical fragment methods based on partitioning atoms or partitioning coordinates.

Science.gov (United States)

Wang, Bo; Yang, Ke R; Xu, Xuefei; Isegawa, Miho; Leverentz, Hannah R; Truhlar, Donald G

2014-09-16

Conspectus The development of more efficient and more accurate ways to represent reactive potential energy surfaces is a requirement for extending the simulation of large systems to more complex systems, longer-time dynamical processes, and more complete statistical mechanical sampling. One way to treat large systems is by direct dynamics fragment methods. Another way is by fitting system-specific analytic potential energy functions with methods adapted to large systems. Here we consider both approaches. First we consider three fragment methods that allow a given monomer to appear in more than one fragment. The first two approaches are the electrostatically embedded many-body (EE-MB) expansion and the electrostatically embedded many-body expansion of the correlation energy (EE-MB-CE), which we have shown to yield quite accurate results even when one restricts the calculations to include only electrostatically embedded dimers. The third fragment method is the electrostatically embedded molecular tailoring approach (EE-MTA), which is more flexible than EE-MB and EE-MB-CE. We show that electrostatic embedding greatly improves the accuracy of these approaches compared with the original unembedded approaches. Quantum mechanical fragment methods share with combined quantum mechanical/molecular mechanical (QM/MM) methods the need to treat a quantum mechanical fragment in the presence of the rest of the system, which is especially challenging for those parts of the rest of the system that are close to the boundary of the quantum mechanical fragment. This is a delicate matter even for fragments that are not covalently bonded to the rest of the system, but it becomes even more difficult when the boundary of the quantum mechanical fragment cuts a bond. We have developed a suite of methods for more realistically treating interactions across such boundaries. These methods include redistributing and balancing the external partial atomic charges and the use of tuned fluorine

Resting state EEG correlates of memory consolidation.

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Brokaw, Kate; Tishler, Ward; Manceor, Stephanie; Hamilton, Kelly; Gaulden, Andrew; Parr, Elaine; Wamsley, Erin J

2016-04-01

Numerous studies demonstrate that post-training sleep benefits human memory. At the same time, emerging data suggest that other resting states may similarly facilitate consolidation. In order to identify the conditions under which non-sleep resting states benefit memory, we conducted an EEG (electroencephalographic) study of verbal memory retention across 15min of eyes-closed rest. Participants (n=26) listened to a short story and then either rested with their eyes closed, or else completed a distractor task for 15min. A delayed recall test was administered immediately following the rest period. We found, first, that quiet rest enhanced memory for the short story. Improved memory was associated with a particular EEG signature of increased slow oscillatory activity (rest can facilitate memory, and that this may occur via an active process of consolidation supported by slow oscillatory EEG activity and characterized by decreased attention to the external environment. Slow oscillatory EEG rhythms are proposed to facilitate memory consolidation during sleep by promoting hippocampal-cortical communication. Our findings suggest that EEG slow oscillations could play a significant role in memory consolidation during other resting states as well. Copyright © 2016 Elsevier Inc. All rights reserved.

General relativistic fields of an isolated spin-half charged particle near the spin axis with application to the rest-mass of the electron and positron

International Nuclear Information System (INIS)

Lynch, J.T.

1999-01-01

Using a lowest-order approximation, the field equations of a general relativistic spinor-connection theory are solved semi-analytically for the fields of a stable, spin-half changed particle near the spin axis. With the exception of the atomic fine-structure constant, all parameters arising in the solution, including the rest mass of the source particle, are found by imposing the standard junction conditions of general relativity and electromagnetism. Using the empirical value for the fine-structure constant, the value derived for the rest mass gives some reason to identify the source particle with the electron. Moreover, since the rest mass is independent of the sign of the electron charge carried by the source, the solution is equally applicable to the positron

The atomic coilgun and single-photon cooling

Energy Technology Data Exchange (ETDEWEB)

Libson, Adam, E-mail: alibson@physics.utexas.edu; Bannerman, Stephen Travis; Clark, Robert J.; Mazur, Thomas R.; Raizen, Mark G. [University of Texas at Austin, Center for Nonlinear Dynamics and Department of Physics (United States)

2012-12-15

As the simplest atom, hydrogen has a unique role as a testing ground of fundamental physics. Precision measurements of the hydrogen atomic structure provide stringent tests of current theory, while tritium is an excellent candidate for studies of {beta}-decay and possible measurement of the neutrino rest mass. Furthermore, precision measurement of antihydrogen would allow for tests of fundamental symmetries. Methods demonstrated in our lab provide an avenue by which hydrogen isotopes can be trapped and cooled to near the recoil limit. The atomic coilgun, which we have demonstrated with metastable neon and molecular oxygen, provides a general method of stopping a supersonic beam of any paramagnetic species. This tool provides a method by which hydrogen and its isotopes can be magnetically trapped at around 100 mK using a room temperature apparatus. Another tool developed in our laboratory, single-photon cooling, allows further cooling of a trapped sample to near the recoil limit. This cooling method has already been demonstrated on a trapped sample of rubidium. We report on the progress of implementing these methods to trap and cool hydrogen isotopes, and on the prospects for using cold trapped hydrogen for precision measurements.

A resting state functional magnetic resonance imaging study of concussion in collegiate athletes.

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Czerniak, Suzanne M; Sikoglu, Elif M; Liso Navarro, Ana A; McCafferty, Joseph; Eisenstock, Jordan; Stevenson, J Herbert; King, Jean A; Moore, Constance M

2015-06-01

Sports-related concussions are currently diagnosed through multi-domain assessment by a medical professional and may utilize neurocognitive testing as an aid. However, these tests have only been able to detect differences in the days to week post-concussion. Here, we investigate a measure of brain function, namely resting state functional connectivity, which may detect residual brain differences in the weeks to months after concussion. Twenty-one student athletes (9 concussed within 6 months of enrollment; 12 non-concussed; between ages 18 and 22 years) were recruited for this study. All participants completed the Wisconsin Card Sorting Task and the Color-Word Interference Test. Neuroimaging data, specifically resting state functional Magnetic Resonance Imaging data, were acquired to examine resting state functional connectivity. Two sample t-tests were used to compare the neurocognitive scores and resting state functional connectivity patterns among concussed and non-concussed participants. Correlations between neurocognitive scores and resting state functional connectivity measures were also determined across all subjects. There were no significant differences in neurocognitive performance between concussed and non-concussed groups. Concussed subjects had significantly increased connections between areas of the brain that underlie executive function. Across all subjects, better neurocognitive performance corresponded to stronger brain connectivity. Even at rest, brains of concussed athletes may have to 'work harder' than their healthy peers to achieve similar neurocognitive results. Resting state brain connectivity may be able to detect prolonged brain differences in concussed athletes in a more quantitative manner than neurocognitive test scores.

A computational study of whole-brain connectivity in resting state and task fMRI

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Goparaju, Balaji; Rana, Kunjan D.; Calabro, Finnegan J.; Vaina, Lucia Maria

2014-01-01

Background We compared the functional brain connectivity produced during resting-state in which subjects were not actively engaged in a task with that produced while they actively performed a visual motion task (task-state). Material/Methods In this paper we employed graph-theoretical measures and network statistics in novel ways to compare, in the same group of human subjects, functional brain connectivity during resting-state fMRI with brain connectivity during performance of a high level visual task. We performed a whole-brain connectivity analysis to compare network statistics in resting and task states among anatomically defined Brodmann areas to investigate how brain networks spanning the cortex changed when subjects were engaged in task performance. Results In the resting state, we found strong connectivity among the posterior cingulate cortex (PCC), precuneus, medial prefrontal cortex (MPFC), lateral parietal cortex, and hippocampal formation, consistent with previous reports of the default mode network (DMN). The connections among these areas were strengthened while subjects actively performed an event-related visual motion task, indicating a continued and strong engagement of the DMN during task processing. Regional measures such as degree (number of connections) and betweenness centrality (number of shortest paths), showed that task performance induces stronger inter-regional connections, leading to a denser processing network, but that this does not imply a more efficient system as shown by the integration measures such as path length and global efficiency, and from global measures such as small-worldness. Conclusions In spite of the maintenance of connectivity and the “hub-like” behavior of areas, our results suggest that the network paths may be rerouted when performing the task condition. PMID:24947491

Qualitative Resting Coronary Pressure Wave Form Analysis to Predict Fractional Flow Reserve.

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Matsumura, Mitsuaki; Maehara, Akiko; Johnson, Nils P; Fearon, William F; De Bruyne, Bernard; Oldroyd, Keith G; Pijls, Nico H J; Jenkins, Paul; Ali, Ziad A; Mintz, Gary S; Stone, Gregg W; Jeremias, Allen

2018-03-27

To evaluate the predictability of resting distal coronary pressure wave forms for fractional flow reserve (FFR). Resting coronary wave forms were qualitatively evaluated for the presence of (i) dicrotic notch; (ii) diastolic dipping; and (iii) ventricularization. In a development cohort (n=88) a scoring system was developed that was then applied to a validation cohort (n=428) using a multivariable linear regression model to predict FFR and receiver operating characteristics (ROC) to predict FFR ≤0.8. In the development cohort, all 3 qualitative parameters were independent predictors of FFR. However, in a multivariable linear regression model in the validation cohort, qualitative wave form analysis did not further improve the ability of resting distal coronary to aortic pressure ratio (Pd/Pa) (p=0.80) or instantaneous wave-free ratio (iFR) (p=0.26) to predict FFR. Using ROC, the area under the curve of resting Pd/Pa (0.86 versus 0.86, P=0.08) and iFR (0.86 versus 0.86, P=0.26) did not improve by adding qualitative analysis. Qualitative coronary wave form analysis showed moderate classification agreement in predicting FFR but did not add substantially to the resting pressure gradients Pd/Pa and iFR; however, when discrepancies between quantitative and qualitative analyses are observed, artifact or pressure drift should be considered.

Recent experiments involving highly excited atoms

International Nuclear Information System (INIS)

Latimer, C.J.

1979-01-01

Very large and fragile atoms may be produced by exciting normal atoms with light or by collisions with other atomic particles. Atoms as large as 10 -6 m are now routinely produced in the laboratory and their properties studied. In this review some of the simpler experimental methods available for the production and detection of such atoms are described including tunable dye laser-excitation and field ionization. A few recent experiments which illustrate the collision properties and the effects of electric and and magnetic fields are also described. The relevance of highly excited atoms in other areas of research including radioastronomy and isotope separation are discussed. (author)

RESTful M2M Gateway for Remote Wireless Monitoring for District Central Heating Networks

Directory of Open Access Journals (Sweden)

Bo Cheng

2014-11-01

Full Text Available In recent years, the increased interest in energy conservation and environmental protection, combined with the development of modern communication and computer technology, has resulted in the replacement of distributed heating by central heating in urban areas. This paper proposes a Representational State Transfer (REST Machine-to-Machine (M2M gateway for wireless remote monitoring for a district central heating network. In particular, we focus on the resource-oriented RESTful M2M gateway architecture, and present an uniform devices abstraction approach based on Open Service Gateway Initiative (OSGi technology, and implement the resource mapping mechanism between resource address mapping mechanism between RESTful resources and the physical sensor devices, and present the buffer queue combined with polling method to implement the data scheduling and Quality of Service (QoS guarantee, and also give the RESTful M2M gateway open service Application Programming Interface (API set. The performance has been measured and analyzed. Finally, the conclusions and future work are presented.

Gold volatile species atomization and preconcentration in quartz devices for atomic absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Arslan, Yasin [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Mehmet Akif Ersoy University, Faculty of Arts & Sciences, Chemistry Department, 15030 Burdur (Turkey); Musil, Stanislav; Matoušek, Tomáš; Kratzer, Jan [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Dědina, Jiří, E-mail: dedina@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic)

2015-01-01

The on-line atomization of gold volatile species was studied and the results were compared with thermodynamic calculations in several quartz atomizers, namely: diffusion flame, flame-in-gas-shield, flame-in-plain-tube, externally heated T-tube and externally heated flame-in-T-tube. Atomization mechanism in the explored devices is proposed, where volatile species are converted to thermodynamically stable AuH at elevated temperature over 500 °C and then atomized by an interaction with a cloud of hydrogen radicals. Because of its inherent simplicity and robustness, diffusion flame was employed as a reference atomizer. It yielded atomization efficiency of 70 to 100% and a very good long time reproducibility of peak area sensitivity: 1.6 to 1.8 s μg{sup −1}. Six and eleven times higher sensitivity, respectively, was provided by atomizers with longer light paths in the observation volume, i.e. externally heated T-tube and externally heated flame-in-T-tube. The latter one, offering limit of detection below 0.01 μg ml{sup −1}, appeared as the most prospective for on-line atomization. Insight into the mechanism of atomization of gold volatile species, into the fate of free atoms and into subsequent analyte transfer allowed to assess possibilities of in-atomizer preconcentration of gold volatile species: it is unfeasible with quartz atomizers but a sapphire tube atomizer could be useful in this respect. - Highlights: • On-line atomization of gold volatile species for AAS in quartz devices was studied. • Atomization mechanism was proposed and atomization efficiency was estimated. • Possibilities of in-atomizer preconcentration of gold volatile species were assessed.

Brain dynamics of post-task resting state are influenced by expertise: Insights from baseball players.

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Muraskin, Jordan; Dodhia, Sonam; Lieberman, Gregory; Garcia, Javier O; Verstynen, Timothy; Vettel, Jean M; Sherwin, Jason; Sajda, Paul

2016-12-01

Post-task resting state dynamics can be viewed as a task-driven state where behavioral performance is improved through endogenous, non-explicit learning. Tasks that have intrinsic value for individuals are hypothesized to produce post-task resting state dynamics that promote learning. We measured simultaneous fMRI/EEG and DTI in Division-1 collegiate baseball players and compared to a group of controls, examining differences in both functional and structural connectivity. Participants performed a surrogate baseball pitch Go/No-Go task before a resting state scan, and we compared post-task resting state connectivity using a seed-based analysis from the supplementary motor area (SMA), an area whose activity discriminated players and controls in our previous results using this task. Although both groups were equally trained on the task, the experts showed differential activity in their post-task resting state consistent with motor learning. Specifically, we found (1) differences in bilateral SMA-L Insula functional connectivity between experts and controls that may reflect group differences in motor learning, (2) differences in BOLD-alpha oscillation correlations between groups suggests variability in modulatory attention in the post-task state, and (3) group differences between BOLD-beta oscillations that may indicate cognitive processing of motor inhibition. Structural connectivity analysis identified group differences in portions of the functionally derived network, suggesting that functional differences may also partially arise from variability in the underlying white matter pathways. Generally, we find that brain dynamics in the post-task resting state differ as a function of subject expertise and potentially result from differences in both functional and structural connectivity. Hum Brain Mapp 37:4454-4471, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals

Resting-State Functional MR Imaging for Determining Language Laterality in Intractable Epilepsy.

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DeSalvo, Matthew N; Tanaka, Naoaki; Douw, Linda; Leveroni, Catherine L; Buchbinder, Bradley R; Greve, Douglas N; Stufflebeam, Steven M

2016-10-01

Purpose To measure the accuracy of resting-state functional magnetic resonance (MR) imaging in determining hemispheric language dominance in patients with medically intractable focal epilepsies against the results of an intracarotid amobarbital procedure (IAP). Materials and Methods This study was approved by the institutional review board, and all subjects gave signed informed consent. Data in 23 patients with medically intractable focal epilepsy were retrospectively analyzed. All 23 patients were candidates for epilepsy surgery and underwent both IAP and resting-state functional MR imaging as part of presurgical evaluation. Language dominance was determined from functional MR imaging data by calculating a laterality index (LI) after using independent component analysis. The accuracy of this method was assessed against that of IAP by using a variety of thresholds. Sensitivity and specificity were calculated by using leave-one-out cross validation. Spatial maps of language components were qualitatively compared among each hemispheric language dominance group. Results Measurement of hemispheric language dominance with resting-state functional MR imaging was highly concordant with IAP results, with up to 96% (22 of 23) accuracy, 96% (22 of 23) sensitivity, and 96% (22 of 23) specificity. Composite language component maps in patients with typical language laterality consistently included classic language areas such as the inferior frontal gyrus, the posterior superior temporal gyrus, and the inferior parietal lobule, while those of patients with atypical language laterality also included non-classical language areas such as the superior and middle frontal gyri, the insula, and the occipital cortex. Conclusion Resting-state functional MR imaging can be used to measure language laterality in patients with medically intractable focal epilepsy. (©) RSNA, 2016 Online supplemental material is available for this article.

Visual food stimulus changes resting oscillatory brain activities related to appetitive motive.

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Yoshikawa, Takahiro; Tanaka, Masaaki; Ishii, Akira; Yamano, Yoko; Watanabe, Yasuyoshi

2016-09-26

Changes of resting brain activities after visual food stimulation might affect the feeling of pleasure in eating food in daily life and spontaneous appetitive motives. We used magnetoencephalography (MEG) to identify brain areas related to the activity changes. Fifteen healthy, right-handed males [age, 25.4 ± 5.5 years; body mass index, 22.5 ± 2.7 kg/m 2 (mean ± SD)] were enrolled. They were asked to watch food or mosaic pictures for 5 min and to close their eyes for 3 min before and after the picture presentation without thinking of anything. Resting brain activities were recorded during two eye-closed sessions. The feeling of pleasure in eating food in daily life and appetitive motives in the study setting were assessed by visual analogue scale (VAS) scores. The γ-band power of resting oscillatory brain activities was decreased after the food picture presentation in the right insula [Brodmann's area (BA) 13], the left orbitofrontal cortex (OFC) (BA11), and the left frontal pole (BA10). Significant reductions of the α-band power were observed in the dorsolateral prefrontal cortex (DLPFC) (BA46). Particularly, the feeling of pleasure in eating food was positively correlated with the power decrease in the insula and negatively with that in the DLPFC. The changes in appetitive motives were associated with the power decrease in the frontal pole. These findings suggest automatic brain mechanics whereby changes of the resting brain activity might be associated with positive feeling in dietary life and have an impact on the irresistible appetitive motives through emotional and cognitive brain functions.

Restful API Architecture Based on Laravel Framework

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Chen, Xianjun; Ji, Zhoupeng; Fan, Yu; Zhan, Yongsong

2017-10-01

Web service has been an industry standard tech for message communication and integration between heterogeneous systems. RESTFUL API has become mainstream web service development paradigm after SOAP, how to effectively construct RESTFUL API remains a research hotspots. This paper presents a development model of RESTFUL API construction based on PHP language and LARAVEL framework. The key technical problems that need to be solved during the construction of RESTFUL API are discussed, and implementation details based on LARAVEL are given.

Effects of irritant chemicals on Aedes aegypti resting behavior: is there a simple shift to untreated "safe sites"?

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Hortance Manda

2011-07-01

Full Text Available BACKGROUND: Previous studies have identified the behavioral responses of Aedes aegypti to irritant and repellent chemicals that can be exploited to reduce man-vector contact. Maximum efficacy of interventions based on irritant chemical actions will, however, require full knowledge of variables that influence vector resting behavior and how untreated "safe sites" contribute to overall impact. METHODS: Using a laboratory box assay, resting patterns of two population strains of female Ae. aegypti (THAI and PERU were evaluated against two material types (cotton and polyester at various dark:light surface area coverage (SAC ratio and contrast configuration (horizontal and vertical under chemical-free and treated conditions. Chemicals evaluated were alphacypermethrin and DDT at varying concentrations. RESULTS: Under chemical-free conditions, dark material had significantly higher resting counts compared to light material at all SAC, and significantly increased when material was in horizontal configuration. Cotton elicited stronger response than polyester. Within the treatment assays, significantly higher resting counts were observed on chemical-treated dark material compared to untreated light fabric. However, compared to matched controls, significantly less resting observations were made on chemical-treated dark material overall. Most importantly, resting observations on untreated light material (or "safe sites" in the treatment assay did not significantly increase for many of the tests, even at 25% SAC. Knockdown rates were ≤5% for all assays. Significantly more observations of flying mosquitoes were made in test assays under chemical-treatment conditions as compared to controls. CONCLUSIONS/SIGNIFICANCE: When preferred Ae. aegypti resting sites are treated with chemicals, even at reduced treatment coverage area, mosquitoes do not simply move to safe sites (untreated areas following contact with the treated material. Instead, they become agitated

Circulating androgens correlate with resting-state MRI in transgender men.

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Mueller, Sven C; Wierckx, Katrien; Jackson, Kathryn; T'Sjoen, Guy

2016-11-01

Despite mounting evidence regarding the underlying neurobiology in transgender persons, information regarding resting-state activity, particularly after hormonal treatment, is lacking. The present study examined differences between transgender persons on long-term cross-sex hormone therapy and comparisons on two measures of local functional connectivity, intensity of spontaneous resting-state activity (low frequency fluctuations, LFF) and local synchronization of specific brain areas (regional homogeneity, ReHo). Nineteen transgender women (TW, male-to-female), 19 transgender men (TM, female-to-male), 21 non-transgender men (NTM) and 20 non-transgender women (NTW) underwent a resting-state MRI scan. The results showed differences between transgender persons and non-transgender comparisons on both LFF and ReHo measures in the frontal cortex, medial temporal lobe, and cerebellum. More interestingly, circulating androgens correlated for TM in the cerebellum and regions of the frontal cortex, an effect that was associated with treatment duration in the cerebellum. By comparison, no associations were found for TW with estrogens. These data provide first evidence for a potential masculinization of local functional connectivity in hormonally-treated transgender men. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantum dynamics of hydrogen atoms on graphene. I. System-bath modeling.

Science.gov (United States)

Bonfanti, Matteo; Jackson, Bret; Hughes, Keith H; Burghardt, Irene; Martinazzo, Rocco

2015-09-28

An accurate system-bath model to investigate the quantum dynamics of hydrogen atoms chemisorbed on graphene is presented. The system comprises a hydrogen atom and the carbon atom from graphene that forms the covalent bond, and it is described by a previously developed 4D potential energy surface based on density functional theory ab initio data. The bath describes the rest of the carbon lattice and is obtained from an empirical force field through inversion of a classical equilibrium correlation function describing the hydrogen motion. By construction, model building easily accommodates improvements coming from the use of higher level electronic structure theory for the system. Further, it is well suited to a determination of the system-environment coupling by means of ab initio molecular dynamics. This paper details the system-bath modeling and shows its application to the quantum dynamics of vibrational relaxation of a chemisorbed hydrogen atom, which is here investigated at T = 0 K with the help of the multi-configuration time-dependent Hartree method. Paper II deals with the sticking dynamics.

Quantum dynamics of hydrogen atoms on graphene. I. System-bath modeling

Energy Technology Data Exchange (ETDEWEB)

Bonfanti, Matteo, E-mail: matteo.bonfanti@unimi.it [Dipartimento di Chimica, Università degli Studi di Milano, v. Golgi 19, 20133 Milano (Italy); Jackson, Bret [Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Hughes, Keith H. [School of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW (United Kingdom); Burghardt, Irene [Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/Main (Germany); Martinazzo, Rocco, E-mail: rocco.martinazzo@unimi.it [Dipartimento di Chimica, Università degli Studi di Milano, v. Golgi 19, 20133 Milano (Italy); Istituto di Scienze e Tecnologie Molecolari, Consiglio Nazionale delle Richerche, v. Golgi 19, 20133 Milano (Italy)

2015-09-28

An accurate system-bath model to investigate the quantum dynamics of hydrogen atoms chemisorbed on graphene is presented. The system comprises a hydrogen atom and the carbon atom from graphene that forms the covalent bond, and it is described by a previously developed 4D potential energy surface based on density functional theory ab initio data. The bath describes the rest of the carbon lattice and is obtained from an empirical force field through inversion of a classical equilibrium correlation function describing the hydrogen motion. By construction, model building easily accommodates improvements coming from the use of higher level electronic structure theory for the system. Further, it is well suited to a determination of the system-environment coupling by means of ab initio molecular dynamics. This paper details the system-bath modeling and shows its application to the quantum dynamics of vibrational relaxation of a chemisorbed hydrogen atom, which is here investigated at T = 0 K with the help of the multi-configuration time-dependent Hartree method. Paper II deals with the sticking dynamics.

Entanglement Dynamics of Linear and Nonlinear Interaction of Two Two-Level Atoms with a Quantized Phase-Damped Field in the Dispersive Regime

Science.gov (United States)

Tavassoly, M. K.; Daneshmand, R.; Rustaee, N.

2018-06-01

In this paper we study the linear and nonlinear (intensity-dependent) interactions of two two-level atoms with a single-mode quantized field far from resonance, while the phase-damping effect is also taken into account. To find the analytical solution of the atom-field state vector corresponding to the considered model, after deducing the effective Hamiltonian we evaluate the time-dependent elements of the density operator using the master equation approach and superoperator method. Consequently, we are able to study the influences of the special nonlinearity function f (n) = √ {n}, the intensity of the initial coherent state field and the phase-damping parameter on the degree of entanglement of the whole system as well as the field and atom. It is shown that in the presence of damping, by passing time, the amount of entanglement of each subsystem with the rest of system, asymptotically reaches to its stationary and maximum value. Also, the nonlinear interaction does not have any effect on the entanglement of one of the atoms with the rest of system, but it changes the amplitude and time period of entanglement oscillations of the field and the other atom. Moreover, this may cause that, the degree of entanglement which may be low (high) at some moments of time becomes high (low) by entering the intensity-dependent function in the atom-field coupling.

What goes on in the resting-state? A qualitative glimpse into resting-state experience in the scanner

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Hurlburt, Russell T.; Alderson-Day, Ben; Fernyhough, Charles; Kühn, Simone

2015-01-01

The brain’s resting-state has attracted considerable interest in recent years, but currently little is known either about typical experience during the resting-state or about whether there are inter-individual differences in resting-state phenomenology. We used descriptive experience sampling (DES) in an attempt to apprehend high fidelity glimpses of the inner experience of five participants in an extended fMRI study. Results showed that the inner experiences and the neural activation patterns (as quantified by amplitude of low frequency fluctuations analysis) of the five participants were largely consistent across time, suggesting that our extended-duration scanner sessions were broadly similar to typical resting-state sessions. However, there were very large individual differences in inner phenomena, suggesting that the resting-state itself may differ substantially from one participant to the next. We describe these individual differences in experiential characteristics and display some typical moments of resting-state experience. We also show that retrospective characterizations of phenomena can often be very different from moment-by-moment reports. We discuss implications for the assessment of inner experience in neuroimaging studies more generally, concluding that it may be possible to use fMRI to investigate neural correlates of phenomena apprehended in high fidelity. PMID:26500590

Separating bedtime rest from activity using waist or wrist-worn accelerometers in youth.

Directory of Open Access Journals (Sweden)

Dustin J Tracy

Full Text Available Recent interest in sedentary behavior and technological advances expanded use of watch-size accelerometers for continuous monitoring of physical activity (PA over extended periods (e.g., 24 h/day for 1 week in studies conducted in natural living environment. This approach necessitates the development of new methods separating bedtime rest and activity periods from the accelerometer recordings. The goal of this study was to develop a decision tree with acceptable accuracy for separating bedtime rest from activity in youth using accelerometer placed on waist or wrist. Minute-by-minute accelerometry data were collected from 81 youth (10-18 years old, 47 females during a monitored 24-h stay in a whole-room indirect calorimeter equipped with a force platform covering the floor to detect movement. Receiver Operating Characteristic (ROC curve analysis was used to determine the accelerometer cut points for rest and activity. To examine the classification differences, the accelerometer bedtime rest and activity classified by the algorithm in the development group (n = 41 were compared with actual bedtime rest and activity classification obtained from the room calorimeter-measured metabolic rate and movement data. The selected optimal bedtime rest cut points were 20 and 250 counts/min for the waist- and the wrist-worn accelerometer, respectively. The selected optimal activity cut points were 500 and 3,000 counts/min for waist and wrist-worn accelerometers, respectively. Bedtime rest and activity were correctly classified by the algorithm in the validation group (n = 40 by both waist- (sensitivity: 0.983, specificity: 0.946, area under ROC curve: 0. 872 and wrist-worn (0.999, 0.980 and 0.943 accelerometers. The decision tree classified bedtime rest correctly with higher accuracy than commonly used automated algorithm for both waist- and wrist-warn accelerometer (all p<0.001. We concluded that cut points developed and validated for waist- and wrist

Regional homogeneity and resting state functional connectivity: associations with exposure to early life stress.

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Philip, Noah S; Kuras, Yuliya I; Valentine, Thomas R; Sweet, Lawrence H; Tyrka, Audrey R; Price, Lawrence H; Carpenter, Linda L

2013-12-30

Early life stress (ELS) confers risk for psychiatric illness. Previous literature suggests ELS is associated with decreased resting-state functional connectivity (rs-FC) in adulthood, but there are no studies of resting-state neuronal activity in this population. This study investigated whether ELS-exposed individuals demonstrate resting-state activity patterns similar to those found in PTSD. Twenty-seven adults (14 with at least moderate ELS), who were medication-free and without psychiatric or medical illness, underwent MRI scans during two 4-minute rest periods. Resting-state activity was examined using regional homogeneity (ReHo), which estimates regional activation patterns through indices of localized concordance. ReHo values were compared between groups, followed by rs-FC analyses utilizing ReHo-localized areas as seeds to identify other involved regions. Relative to controls, ELS subjects demonstrated diminished ReHo in the inferior parietal lobule (IPL) and superior temporal gyrus (STG). ReHo values were inversely correlated with ELS severity. Secondary analyses revealed decreased rs-FC between the IPL and right precuneus/posterior cingulate, left fusiform gyrus, cerebellum and caudate in ELS subjects. These findings indicate that ELS is associated with altered resting-state activity and connectivity in brain regions involved in trauma-related psychiatric disorders. Future studies are needed to evaluate whether these associations represent potential imaging biomarkers of stress exposure. Published by Elsevier Ireland Ltd.

Theoretical atomic physics for fusion. 1995 annual report

International Nuclear Information System (INIS)

Pindzola, M.S.

1995-01-01

The understanding of electron-ion collision processes in plasmas remains a key factor in the ultimate development of nuclear fusion as a viable energy source for the nation. The 1993--1995 research proposal delineated several areas of research in electron-ion scattering theory. In this report the author summarizes his efforts in 1995. The main areas of research are: (1) electron-impact excitation of atomic ions; (2) electron-impact ionization of atomic ions; and (3) electron-impact recombination of atomic ions

The influence of mosquito resting behaviour and associated microclimate for malaria risk

Directory of Open Access Journals (Sweden)

Thomas Matthew B

2011-07-01

Full Text Available Abstract Background The majority of the mosquito and parasite life-history traits that combine to determine malaria transmission intensity are temperature sensitive. In most cases, the process-based models used to estimate malaria risk and inform control and prevention strategies utilize measures of mean outdoor temperature. Evidence suggests, however, that certain malaria vectors can spend large parts of their adult life resting indoors. Presentation of hypothesis If significant proportions of mosquitoes are resting indoors and indoor conditions differ markedly from ambient conditions, simple use of outdoor temperatures will not provide reliable estimates of malaria transmission intensity. To date, few studies have quantified the differential effects of indoor vs outdoor temperatures explicitly, reflecting a lack of proper understanding of mosquito resting behaviour and associated microclimate. Testing the hypothesis Published records from 8 village sites in East Africa revealed temperatures to be warmer indoors than outdoors and to generally show less daily variation. Exploring the effects of these temperatures on malaria parasite development rate suggested indoor-resting mosquitoes could transmit malaria between 0.3 and 22.5 days earlier than outdoor-resting mosquitoes. These differences translate to increases in transmission risk ranging from 5 to approaching 3,000%, relative to predictions based on outdoor temperatures. The pattern appears robust for low- and highland areas, with differences increasing with altitude. Implications of the hypothesis Differences in indoor vs outdoor environments lead to large differences in the limits and the intensity of malaria transmission. This finding highlights a need to better understand mosquito resting behaviour and the associated microclimate, and to broaden assessments of transmission ecology and risk to consider the potentially important role of endophily.

Rest tremor in idiopathic adult-onset dystonia.

Science.gov (United States)

Gigante, A F; Berardelli, A; Defazio, G

2016-05-01

Tremor in dystonia has been described as a postural or kinetic abnormality. In recent series, however, patients with idiopathic adult-onset dystonia also displayed rest tremor. The frequency and distribution of rest tremor were studied in a cohort of 173 consecutive Italian patients affected by various forms of idiopathic adult-onset dystonia attending our movement disorder clinic over 8 months. Examination revealed tremor in 59/173 patients (34%): 12 patients had head tremor, 34 patients had arm tremor, whilst 13 patients presented tremor in both sites. Head tremor was postural in all patients, whereas arm tremor was postural/kinetic in 28 patients, only at rest in one and both postural/kinetic and at rest in 18 patients. Patients with tremor were more likely to have segmental/multifocal dystonia. Patients who had rest tremor (either alone or associated with action tremor) had a higher age at dystonia onset and a greater frequency of dystonic arm involvement than patients with action tremor alone or without tremor. Both action and rest tremor are part of the tremor spectrum of adult-onset dystonia and are more frequently encountered in segmental/multifocal dystonia. The higher age at dystonia onset and the greater frequency of arm dystonia in patients with rest tremor may have pathophysiological implications and may account, at least in part, for the previous lack of identification of rest tremor as one possible type of tremor present in dystonia. © 2016 EAN.

Atoms, molecules and optical physics 1. Atoms and spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hertel, Ingolf V.; Schulz, Claus-Peter

2015-09-01

This is the first volume of textbooks on atomic, molecular and optical physics, aiming at a comprehensive presentation of this highly productive branch of modern physics as an indispensable basis for many areas in physics and chemistry as well as in state of the art bio- and material-sciences. It primarily addresses advanced students (including PhD students), but in a number of selected subject areas the reader is lead up to the frontiers of present research. Thus even the active scientist is addressed. This volume 1 provides the canonical knowledge in atomic physics together with basics of modern spectroscopy. Starting from the fundamentals of quantum physics, the reader is familiarized in well structured chapters step by step with the most important phenomena, models and measuring techniques. The emphasis is always on the experiment and its interpretation, while the necessary theory is introduced from this perspective in a compact and occasionally somewhat heuristic manner, easy to follow even for beginners.

Resting-State Seed-Based Analysis: An Alternative to Task-Based Language fMRI and Its Laterality Index.

Science.gov (United States)

Smitha, K A; Arun, K M; Rajesh, P G; Thomas, B; Kesavadas, C

2017-06-01

Language is a cardinal function that makes human unique. Preservation of language function poses a great challenge for surgeons during resection. The aim of the study was to assess the efficacy of resting-state fMRI in the lateralization of language function in healthy subjects to permit its further testing in patients who are unable to perform task-based fMRI. Eighteen healthy right-handed volunteers were prospectively evaluated with resting-state fMRI and task-based fMRI to assess language networks. The laterality indices of Broca and Wernicke areas were calculated by using task-based fMRI via a voxel-value approach. We adopted seed-based resting-state fMRI connectivity analysis together with parameters such as amplitude of low-frequency fluctuation and fractional amplitude of low-frequency fluctuation (fALFF). Resting-state fMRI connectivity maps for language networks were obtained from Broca and Wernicke areas in both hemispheres. We performed correlation analysis between the laterality index and the z scores of functional connectivity, amplitude of low-frequency fluctuation, and fALFF. Pearson correlation analysis between signals obtained from the z score of fALFF and the laterality index yielded a correlation coefficient of 0.849 ( P laterality index yielded an R 2 value of 0.721, indicating that 72.1% of the variance in the laterality index of task-based fMRI could be predicted from the fALFF of resting-state fMRI. The present study demonstrates that fALFF can be used as an alternative to task-based fMRI for assessing language laterality. There was a strong positive correlation between the fALFF of the Broca area of resting-state fMRI with the laterality index of task-based fMRI. Furthermore, we demonstrated the efficacy of fALFF for predicting the laterality of task-based fMRI. © 2017 by American Journal of Neuroradiology.

Physiology Of Prolonged Bed Rest

Science.gov (United States)

Greenleaf, John E.

1991-01-01

Report describes physiological effects of prolonged bed rest. Rest for periods of 24 hours or longer deconditions body to some extent; healing proceeds simultaneously with deconditioning. Report provides details on shifts in fluid electrolytes and loss of lean body mass, which comprises everything in body besides fat - that is, water, muscle, and bone. Based on published research.

Quantum Electronics for Atomic Physics

CERN Document Server

Nagourney, Warren

2010-01-01

Quantum Electronics for Atomic Physics provides a course in quantum electronics for researchers in atomic physics. The book covers the usual topics, such as Gaussian beams, cavities, lasers, nonlinear optics and modulation techniques, but also includes a number of areas not usually found in a textbook on quantum electronics. It includes such practical matters as the enhancement of nonlinear processes in a build-up cavity, impedance matching into a cavity, laser frequencystabilization (including servomechanism theory), astigmatism in ring cavities, and atomic/molecular spectroscopic techniques

Dose and effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats

Science.gov (United States)

Dose and effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats Authors: Gary E. Hatch, John McKee, James Brown, Bill McDonnell, Elston Seal, Joleen Soukup, Ralph Slade, Kay Crissman and Robert Devlin, National Health and Environmental...

Electromagnetic trapping of neutral atoms

International Nuclear Information System (INIS)

Metcalf, H.J.

1986-01-01

Cooling and trapping of neutral atoms is a new branch of applied physics that has potential for application in many areas. The authors present an introduction to laser cooling and magnetic trapping. Some basic ideas and fundamental limitations are discussed, and the first successful experiments are reviewed. Trapping a neutral object depends on the interaction between an inhomogeneous electromagnetic field and a multiple moment that results in the exchange of kinetic for potential energy. In neutral atom traps, the potential energy must be stored as internal atomic energy, resulting in two immediate and extremely important consequences. First, the atomic energy levels will necessarily shift as the atoms move in the trap, and, second, practical traps for ground state neutral atoms atr necessarily very shallow compared to thermal energy. This small depth also dictates stringent vacuum requirements because a trapped atom cannot survive a single collision with a thermal energy background gas molecule. Neutral trapping, therefore, depends on substantial cooling of a thermal atomic sample and is inextricably connected with the cooling process

Advances in atomic spectroscopy

CERN Document Server

Sneddon, J

1998-01-01

This volume continues the series'' cutting-edge reviews on developments in this field. Since its invention in the 1920s, electrostatic precipitation has been extensively used in industrial hygiene to remove dust and particulate matter from gases before entering the atmosphere. This combination of electrostatic precipitation is reported upon in the first chapter. Following this, chapter two reviews recent advances in the area of chemical modification in electrothermal atomization. Chapter three consists of a review which deal with advances and uses of electrothermal atomization atomic absorption spectrometry. Flow injection atomic spectroscopy has developed rapidly in recent years and after a general introduction, various aspects of this technique are looked at in chapter four. Finally, in chapter five the use of various spectrometric techniques for the determination of mercury are described.

The Physiology of Bed Rest. Chapter 39

Science.gov (United States)

Fortney, Suzanne M.; Schneider, Victor S.; Greenleaf, John E.

1996-01-01

Prolonged rest in bed has been utilized by physicians and other health-care workers to immobilize and confine patients for rehabilitation and restoration of health since time immemorial. The sitting or horizontal position is sought by the body to relieve the strain of the upright or vertical postures, for example during syncopal situations, bone fractures, muscle injuries, fatigue, and probably also to reduce energy expenditure. Most health-care personnel are aware that adaptive responses occurring during bed rest proceed concomitantly with the healing process; signs and symptoms associated with the former should be differentiated from those of the latter. Not all illnesses and infirmities benefit from prolonged bed rest. Considerations in prescribing bed rest for patients-including duration, body position, mode and duration of exercise, light-dark cycles, temperature, and humidity-have not been investigated adequately. More recently, adaptive physiological responses have been measured in normal, healthy subjects in the horizontal or slightly head-down postures during prolonged bed rest as analogs for the adaptive responses of astronauts exposed to the microgravity environment of outer and bed-rest research.

Recognizing mild cognitive impairment based on network connectivity analysis of resting EEG with zero reference

International Nuclear Information System (INIS)

Xu, Peng; Xiong, Xiu Chun; Tian, Yin; Zhang, Rui; Li, Pei Yang; Yao, De Zhong; Xue, Qing; Wang, Yu Ping; Peng, Yueheng

2014-01-01

The diagnosis of mild cognitive impairment (MCI) is very helpful for early therapeutic interventions of Alzheimer's disease (AD). MCI has been proven to be correlated with disorders in multiple brain areas. In this paper, we used information from resting brain networks at different EEG frequency bands to reliably recognize MCI. Because EEG network analysis is influenced by the reference that is used, we also evaluate the effect of the reference choices on the resting scalp EEG network-based MCI differentiation. The conducted study reveals two aspects: (1) the network-based MCI differentiation is superior to the previously reported classification that uses coherence in the EEG; and (2) the used EEG reference influences the differentiation performance, and the zero approximation technique (reference electrode standardization technique, REST) can construct a more accurate scalp EEG network, which results in a higher differentiation accuracy for MCI. This study indicates that the resting scalp EEG-based network analysis could be valuable for MCI recognition in the future. (paper)

Visual learning alters the spontaneous activity of the resting human brain: an fNIRS study.

Science.gov (United States)

Niu, Haijing; Li, Hao; Sun, Li; Su, Yongming; Huang, Jing; Song, Yan

2014-01-01

Resting-state functional connectivity (RSFC) has been widely used to investigate spontaneous brain activity that exhibits correlated fluctuations. RSFC has been found to be changed along the developmental course and after learning. Here, we investigated whether and how visual learning modified the resting oxygenated hemoglobin (HbO) functional brain connectivity by using functional near-infrared spectroscopy (fNIRS). We demonstrate that after five days of training on an orientation discrimination task constrained to the right visual field, resting HbO functional connectivity and directed mutual interaction between high-level visual cortex and frontal/central areas involved in the top-down control were significantly modified. Moreover, these changes, which correlated with the degree of perceptual learning, were not limited to the trained left visual cortex. We conclude that the resting oxygenated hemoglobin functional connectivity could be used as a predictor of visual learning, supporting the involvement of high-level visual cortex and the involvement of frontal/central cortex during visual perceptual learning.

The Gyllingnaes investigation - a survey of altitudes in the Gylling postal area towards atomic power

International Nuclear Information System (INIS)

Boldsen, N.; Buelow, W.

1977-01-01

An investigation of the altitudes of the local population towards the possible construction of an atomic power station at Gyllingnaes in Denmark. It is primarily based on questionnaries, secondarily on interviews. To put the results in better perspective, similar investigations from 1974-1976 are also dealt with. It is concluded that the majority of the population are against atomic power; not only do they oppose the erection of an atomic power station at Gyllingnaes but they oppose the building of atomic power stations in general. An attempt is made to characterize the ''typical'' opponent and the ''typical'' supporter of atomic power. (B.P.)

Auditory Hallucinations and the Brain’s Resting-State Networks: Findings and Methodological Observations

Science.gov (United States)

Alderson-Day, Ben; Diederen, Kelly; Fernyhough, Charles; Ford, Judith M.; Horga, Guillermo; Margulies, Daniel S.; McCarthy-Jones, Simon; Northoff, Georg; Shine, James M.; Turner, Jessica; van de Ven, Vincent; van Lutterveld, Remko; Waters, Flavie; Jardri, Renaud

2016-01-01

In recent years, there has been increasing interest in the potential for alterations to the brain’s resting-state networks (RSNs) to explain various kinds of psychopathology. RSNs provide an intriguing new explanatory framework for hallucinations, which can occur in different modalities and population groups, but which remain poorly understood. This collaboration from the International Consortium on Hallucination Research (ICHR) reports on the evidence linking resting-state alterations to auditory hallucinations (AH) and provides a critical appraisal of the methodological approaches used in this area. In the report, we describe findings from resting connectivity fMRI in AH (in schizophrenia and nonclinical individuals) and compare them with findings from neurophysiological research, structural MRI, and research on visual hallucinations (VH). In AH, various studies show resting connectivity differences in left-hemisphere auditory and language regions, as well as atypical interaction of the default mode network and RSNs linked to cognitive control and salience. As the latter are also evident in studies of VH, this points to a domain-general mechanism for hallucinations alongside modality-specific changes to RSNs in different sensory regions. However, we also observed high methodological heterogeneity in the current literature, affecting the ability to make clear comparisons between studies. To address this, we provide some methodological recommendations and options for future research on the resting state and hallucinations. PMID:27280452

High spatial correspondence at a columnar level between activation and resting state fMRI signals and local field potentials.

Science.gov (United States)

Shi, Zhaoyue; Wu, Ruiqi; Yang, Pai-Feng; Wang, Feng; Wu, Tung-Lin; Mishra, Arabinda; Chen, Li Min; Gore, John C

2017-05-16

Although blood oxygenation level-dependent (BOLD) fMRI has been widely used to map brain responses to external stimuli and to delineate functional circuits at rest, the extent to which BOLD signals correlate spatially with underlying neuronal activity, the spatial relationships between stimulus-evoked BOLD activations and local correlations of BOLD signals in a resting state, and whether these spatial relationships vary across functionally distinct cortical areas are not known. To address these critical questions, we directly compared the spatial extents of stimulated activations and the local profiles of intervoxel resting state correlations for both high-resolution BOLD at 9.4 T and local field potentials (LFPs), using 98-channel microelectrode arrays, in functionally distinct primary somatosensory areas 3b and 1 in nonhuman primates. Anatomic images of LFP and BOLD were coregistered within 0.10 mm accuracy. We found that the point spread functions (PSFs) of BOLD and LFP responses were comparable in the stimulus condition, and both estimates of activations were slightly more spatially constrained than local correlations at rest. The magnitudes of stimulus responses in area 3b were stronger than those in area 1 and extended in a medial to lateral direction. In addition, the reproducibility and stability of stimulus-evoked activation locations within and across both modalities were robust. Our work suggests that the intrinsic resolution of BOLD is not a limiting feature in practice and approaches the intrinsic precision achievable by multielectrode electrophysiology.

The Effects of Long Duration Bed Rest as a Spaceflight Analogue on Resting State Sensorimotor Network Functional Connectivity and Neurocognitive Performance

Science.gov (United States)

Cassady, K.; Koppelmans, V.; Yuan, P.; Cooke, K.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.;

Stress hormones at rest and following exercise testing predict coronary artery disease severity and outcome.

Science.gov (United States)

Popovic, Dejana; Damjanovic, Svetozar; Djordjevic, Tea; Martic, Dejana; Ignjatovic, Svetlana; Milinkovic, Neda; Banovic, Marko; Lasica, Ratko; Petrovic, Milan; Guazzi, Marco; Arena, Ross

2017-09-01

Despite considerable knowledge regarding the importance of stress in coronary artery disease (CAD) pathogenesis, its underestimation persists in routine clinical practice, in part attributable to lack of a standardized, objective assessment. The current study examined the ability of stress hormones to predict CAD severity and prognosis at basal conditions as well as during and following an exertional stimulus. Forty Caucasian subjects with significant coronary artery lesions (≥50%) were included. Within 2 months of coronary angiography, cardiopulmonary exercise testing (CPET) on a recumbent ergometer was performed in conjunction with stress echocardiography (SE). At rest, peak and after 3 min of recovery following CPET, plasma levels of cortisol, adrenocorticotropic hormone (ACTH) and NT-pro-brain natriuretic peptide (NT-pro-BNP) were measured by immunoassay sandwich technique, radioimmunoassay, and radioimmunometric technique, respectively. Subjects were subsequently followed a mean of 32 ± 10 months. Mean ejection fraction was 56.7 ± 9.6%. Subjects with 1-2 stenotic coronary arteries (SCA) demonstrated a significantly lower plasma cortisol levels during CPET compared to those with 3-SCA (p  .05). Among CPET, SE, and hormonal parameters, cortisol at rest and during CPET recovery demonstrated the best predictive value in distinguishing between 1-, 2-, and 3-SCA [area under ROC curve 0.75 and 0.77 (SE = 0.11, 0.10; p = .043, .04) for rest and recovery, respectively]. ΔCortisol peak/rest predicted cumulative cardiac events (area under ROC curve 0.75, SE = 0.10, p = .049). Cortisol at rest and following an exercise test holds predictive value for CAD severity and prognosis, further demonstrating a link between stress and unwanted cardiac events.

Atomic cluster collisions

Science.gov (United States)

Korol, Andrey V.; Solov'yov, Andrey

2013-01-01

Atomic cluster collisions are a field of rapidly emerging research interest by both experimentalists and theorists. The international symposium on atomic cluster collisions (ISSAC) is the premier forum to present cutting-edge research in this field. It was established in 2003 and the most recent conference was held in Berlin, Germany in July of 2011. This Topical Issue presents original research results from some of the participants, who attended this conference. This issues specifically focuses on two research areas, namely Clusters and Fullerenes in External Fields and Nanoscale Insights in Radiation Biodamage.

A study of public acceptance of construction of atomic power plant

International Nuclear Information System (INIS)

Harada, Kazunori; Matsuhashi, Ryuji; Yoshida, Yoshikuni

2011-01-01

In June 2010, Basic Energy Plan was approved in a Cabinet meeting. It says that Japan aims to construct more than 14 atomic power plants by 2030. Today, there are 12 plans of construction of atomic power plant, but it is hard to say that their plans easily come off. That's because public acceptance of atomic power plant is low in Japan, for example local residents wage opposition campaigns. This study conducts a survey in the form of a questionnaire and analyzes it by Analytical Hierarchical Process (AHP). Analytic Hierarchy Process is a structured technique for dealing with complex decisions. A questionnaire using AHP is very easy to answer and analyze. This survey was conducted in 2 areas. First area is Hohoku-cho, Yamaguchi Pref. that had a plan of construction of atomic power plant and the plan was demolished by opposition campaigns. Second area is Kaminoseki-cho, Yamaguchi Pref. that has a plan of construction of atomic power plant now and the plan is working order. Public acceptance can be calculated from survey data of 2 areas, and it helps to understand why first area disapproved a plan of atomic power plant and second area approves it. We consider a model to analyze public acceptance. (author)

Physiological responses of women to simulated weightlessness: A review of the first female bed-rest study

Science.gov (United States)

Sandler, H.; Winter, D. L.

1978-01-01

Subjects were exposed to centrifugation, to lower body negative pressure (LBNP), and to exericse stress both before and after bed rest. Areas studied were centrifugation tolerance, fluid electrolyte changes and hematology, tolerance to LBNP, physical working capacity, biochemistries, blood fibrinolytic activity, female metabolic and hormonal responses, circadian alterations, and gynecology. Results were compared with the responses observed in similarly bed-rested male subjects. The bed-rested females showed deconditioning responses similar to those of the males, although with some differences. Results indicate that women are capable of coping with exposure to weightlessness and, moreover, that they may be more sensitive subjects for evaluating countermeasures to weightlessness and developing criteria for assessing applicants for shuttle voyages.

Atom-by-atom assembly

International Nuclear Information System (INIS)

Hla, Saw Wai

2014-01-01

Atomic manipulation using a scanning tunneling microscope (STM) tip enables the construction of quantum structures on an atom-by-atom basis, as well as the investigation of the electronic and dynamical properties of individual atoms on a one-atom-at-a-time basis. An STM is not only an instrument that is used to ‘see’ individual atoms by means of imaging, but is also a tool that is used to ‘touch’ and ‘take’ the atoms, or to ‘hear’ their movements. Therefore, the STM can be considered as the ‘eyes’, ‘hands’ and ‘ears’ of the scientists, connecting our macroscopic world to the exciting atomic world. In this article, various STM atom manipulation schemes and their example applications are described. The future directions of atomic level assembly on surfaces using scanning probe tips are also discussed. (review article)

Rydberg atoms in weak magnetic fields

International Nuclear Information System (INIS)

Kazantsev, A.P.; Pokrovsky, V.L.; Bergou, J.

1983-01-01

The quadratic Zeeman effect of Rydberg atoms in the framework of perturbation theory is dealt with and a special quasiclassical approximation scheme is applied. The Bohr-Sommerfeld quantization condition is given in terms of complete elliptic integrals. It is shown that part of the spectrum is doubly degenerate, the corresponding states are asymmetric with respect to the Coulomb centre and have a non-zero dipole moment; the rest of the spectrum is nondegenerate, the states are symmetric and their dipole-moment vanishes. The transition from the symmetric to the asymmetric region is similar to a phase transition and it gives an experimental possibility to distinguish between the two types of states. (author)

An aerial radiological survey of the Enrico Fermi Atomic Power Plant and surrounding area, Newport, Michigan

International Nuclear Information System (INIS)

1986-05-01

An aerial radiological survey was performed over the area surrounding the Enrico Fermi Atomic Power Plant during the period 27 to 30 May 1986. The survey covered a 64-square-kilometer (25-square-mile) area around the plant. The deteted radiation was due to the presence of varying concentrations of naturally-occurring radioactive materials. Radionuclides of the uranium and thorium decay chains and radioactive potassium were found. For the majority of the survey area, the inferred radiation exposure rate levels varied between 10 and 12 microroentgens per hour (μR/h). The reported exposure rate values included an estimated cosmic ray contribution of 3.7 μR/h. Ground-based measurements, conducted concurrently with the aerial survey, were compared to the inferred aerial results. Pressurized ionization chamber readings and a group of soil samples were acquired at five locations within the survey area. The exposure rate values obtained from these ground-based measurements were in good agreement with the corresponding inferred aerial values. No evidence was found of any radioactive contamination which might have occurred as a result of plant operations. This conclusion was supported by the results of the soil samples analyses and the comparison of the current survey data with those obtained in September 1970. 7 refs., 5 figs., 1 tab

Atoms in Flight: The Remarkable Connections between Atomic and Hadronic Physics

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Stanley J.; /SLAC

2012-02-16

Atomic physics and hadron physics are both based on Yang Mills gauge theory; in fact, quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics provide important insight into the theory of hadrons in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of light-front relativistic equations of motion which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The renormalization scale for the running coupling, which is unambiguously set in QED, leads to a method for setting the renormalization scale in QCD. The production of atoms in flight provides a method for computing the formation of hadrons at the amplitude level. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, and light-front quantization have equal utility for atomic physics, especially in the relativistic domain. I also present a new perspective for understanding the contributions to the cosmological constant from QED and QCD.

Mechanisms and energetics of surface atomic processes

International Nuclear Information System (INIS)

Tsong, T.T.

1991-01-01

The energies involved in various surface atomic processes such as surface diffusion, the binding of small atomic clusters on the surface, the interaction between two adsorbed atoms, the dissociation of an atom from a small cluster or from a surface layer, the binding of kink size atoms or atoms at different adsorption sites to the surface etc., can be derived from an analysis of atomically resolved field ion microscope images and a kinetic energy measurement of low temperature field desorbed ions using the time-of-flight atom-probe field ion microscope. These energies can be used to compare with theories and to understand the transport of atoms on the surface in atomic reconstructions, epitaxial growth of surface layers and crystal growth, adsorption layer superstructure formation, and also why an atomic ordering or atomic reconstruction at the surface is energetically favored. Mechanisms of some of the surface atomic processes are also clarified from these quantitative, atomic resolution studies. In this paper work in this area is bris briefly reviewed

Abnormal Resting-State Functional Connectivity in Progressive Supranuclear Palsy and Corticobasal Syndrome

Directory of Open Access Journals (Sweden)

Komal Bharti

2017-06-01

Full Text Available BackgroundPathological and MRI-based evidence suggests that multiple brain structures are likely to be involved in functional disconnection between brain areas. Few studies have investigated resting-state functional connectivity (rsFC in progressive supranuclear palsy (PSP and corticobasal syndrome (CBS. In this study, we investigated within- and between-network rsFC abnormalities in these two conditions.MethodsTwenty patients with PSP, 11 patients with CBS, and 16 healthy subjects (HS underwent a resting-state fMRI study. Resting-state networks (RSNs were extracted to evaluate within- and between-network rsFC using the Melodic and FSLNets software packages.ResultsIncreased within-network rsFC was observed in both PSP and CBS patients, with a larger number of RSNs being involved in CBS. Within-network cerebellar rsFC positively correlated with mini-mental state examination scores in patients with PSP. Compared to healthy volunteers, PSP and CBS patients exhibit reduced functional connectivity between the lateral visual and auditory RSNs, with PSP patients additionally showing lower functional connectivity between the cerebellar and insular RSNs. Moreover, rsFC between the salience and executive-control RSNs was increased in patients with CBS compared to HS.ConclusionThis study provides evidence of functional brain reorganization in both PSP and CBS. Increased within-network rsFC could represent a higher degree of synchronization in damaged brain areas, while between-network rsFC abnormalities may mainly reflect degeneration of long-range white matter fibers.

Functional connectivity of the dorsal and median raphe nuclei at rest

DEFF Research Database (Denmark)

Beliveau, Vincent; Svarer, Claus; Frokjaer, Vibe G

2015-01-01

Serotonin (5-HT) is a neurotransmitter critically involved in a broad range of brain functions and implicated in the pathophysiology of neuropsychiatric illnesses including major depression, anxiety and sleep disorders. Despite being widely distributed throughout the brain, there is limited...... knowledge on the contribution of 5-HT to intrinsic brain activity. The dorsal raphe (DR) and median raphe (MR) nuclei are the source of most serotonergic neurons projecting throughout the brain and thus provide a compelling target for a seed-based probe of resting-state activity related to 5-HT. Here we...... implemented a novel multimodal neuroimaging approach for investigating resting-state functional connectivity (FC) between DR and MR and cortical, subcortical and cerebellar target areas. Using [(11)C]DASB positron emission tomography (PET) images of the brain serotonin transporter (5-HTT) combined...

Framework for ReSTful Web Services in OSGi

Science.gov (United States)

Shams, Khawaja S.; Norris, Jeffrey S.; Powell, Mark W.; Crockett, Thomas M.; Mittman, David S.; Fox, Jason M.; Joswig, Joseph C.; Wallick, Michael N.; Torres, Recaredo J.; Rabe, Kenneth

2009-01-01

Ensemble ReST is a software system that eases the development, deployment, and maintenance of server-side application programs to perform functions that would otherwise be performed by client software. Ensemble ReST takes advantage of the proven disciplines of ReST (Representational State Transfer. ReST leverages the standardized HTTP protocol to enable developers to offer services to a diverse variety of clients: from shell scripts to sophisticated Java application suites

Exercise countermeasures for bed-rest deconditioning

Science.gov (United States)

Greenleaf, John (Editor)

1993-01-01

The purpose for this 30-day bed rest study was to investigate the effects of short-term, high intensity isotonic and isokinetic exercise training on maintenance of working capacity (peak oxygen uptake), muscular strength and endurance, and on orthostatic tolerance, posture and gait. Other data were collected on muscle atrophy, bone mineralization and density, endocrine analyses concerning vasoactivity and fluid-electrolyte balance, muscle intermediary metabolism, and on performance and mood of the subjects. It was concluded that: The subjects maintained a relatively stable mood, high morale, and high esprit de corps throughout the study. Performance improved in nearly all tests in almost all the subjects. Isotonic training, as opposed to isokinetic exercise training, was associated more with decreasing levels of psychological tension, concentration, and motivation; and improvement in the quality of sleep. Working capacity (peak oxygen uptake) was maintained during bed rest with isotonic exercise training; it was not maintained with isokinetic or no exercise training. In general, there was no significant decrease in strength or endurance of arm or leg muscles during bed rest, in spite of some reduction in muscle size (atrophy) of some leg muscles. There was no effect of isotonic exercise training on orthostasis, since tilt-table tolerance was reduced similarly in all three groups following bed rest. Bed rest resulted in significant decreases of postural stability and self-selected step length, stride length, and walking velocity, which were not influenced by either exercise training regimen. Most pre-bed rest responses were restored by the fourth day of recovery.

Stopping atoms with diode lasers

International Nuclear Information System (INIS)

Watts, R.N.; Wieman, C.E.

1986-01-01

The use of light pressure to cool and stop neutral atoms has been an area of considerable interest recently. Cooled neutral atoms are needed for a variety of interesting experiments involving neutral atom traps and ultrahigh-resolution spectroscopy. Laser cooling of sodium has previously been demonstrated using elegant but quite elaborate apparatus. These techniques employed stabilized dye lasers and a variety of additional sophisticated hardware. The authors have demonstrated that a frequency chirp technique can be implemented using inexpensive diode lasers and simple electronics. In this technique the atoms in an atomic beam scatter resonant photons from a counterpropagating laser beam. The momentum transfer from the photons slows the atoms. The primary difficulty is that as the atoms slow their Doppler shift changes, and so they are no longer in resonance with the incident photons. In the frequency chirp technique this is solved by rapidly changing the laser frequency so that the atoms remain in resonance. To achieve the necessary frequency sweep with a dye laser one must use an extremely sophisticated high-speed electrooptic modulator. With a diode laser, however, the frequency can be smoothly and rapidly varied over many gigahertz simply by changing the injection current

Resting-state FMRI confounds and cleanup

Science.gov (United States)

Murphy, Kevin; Birn, Rasmus M.; Bandettini, Peter A.

2013-01-01

The goal of resting-state functional magnetic resonance imaging (FMRI) is to investigate the brain’s functional connections by using the temporal similarity between blood oxygenation level dependent (BOLD) signals in different regions of the brain “at rest” as an indicator of synchronous neural activity. Since this measure relies on the temporal correlation of FMRI signal changes between different parts of the brain, any non-neural activity-related process that affects the signals will influence the measure of functional connectivity, yielding spurious results. To understand the sources of these resting-state FMRI confounds, this article describes the origins of the BOLD signal in terms of MR physics and cerebral physiology. Potential confounds arising from motion, cardiac and respiratory cycles, arterial CO2 concentration, blood pressure/cerebral autoregulation, and vasomotion are discussed. Two classes of techniques to remove confounds from resting-state BOLD time series are reviewed: 1) those utilising external recordings of physiology and 2) data-based cleanup methods that only use the resting-state FMRI data itself. Further methods that remove noise from functional connectivity measures at a group level are also discussed. For successful interpretation of resting-state FMRI comparisons and results, noise cleanup is an often over-looked but essential step in the analysis pipeline. PMID:23571418

Changes in Resting-State Connectivity following Melody-Based Therapy in a Patient with Aphasia

Directory of Open Access Journals (Sweden)

Tali Bitan

2018-01-01

Full Text Available Melody-based treatments for patients with aphasia rely on the notion of preserved musical abilities in the RH, following left hemisphere damage. However, despite evidence for their effectiveness, the role of the RH is still an open question. We measured changes in resting-state functional connectivity following melody-based intervention, to identify lateralization of treatment-related changes. A patient with aphasia due to left frontal and temporal hemorrhages following traumatic brain injuries (TBI more than three years earlier received 48 sessions of melody-based intervention. Behavioral measures improved and were maintained at the 8-week posttreatment follow-up. Resting-state fMRI data collected before and after treatment showed an increase in connectivity between motor speech control areas (bilateral supplementary motor areas and insulae and RH language areas (inferior frontal gyrus pars triangularis and pars opercularis. This change, which was specific for the RH, was greater than changes in a baseline interval measured before treatment. No changes in RH connectivity were found in a matched control TBI patient scanned at the same intervals. These results are compatible with a compensatory role for RH language areas following melody-based intervention. They further suggest that this therapy intervenes at the level of the interface between language areas and speech motor control areas necessary for language production.

Same day injections of Tc-99m methoxy isobutyl isonitrile (hexamibi) for myocardial tomographic imaging: Comparison between rest-stress and stress-rest injection sequences

International Nuclear Information System (INIS)

Taillefer, R.; Gagnon, A.; Laflamme, L.; Leveille, J.; Phaneuf, D.C.

1989-01-01

It has been shown that both rest and stress 99m Tc-hexamibi myocardial perfusion imaging can be performed on the same day using two different doses injected within few h (the first one at rest followed by a second at stress). In order to evaluate and compare 2 sequences (rest-stress and stress-rest) of 99m Tc-hexamibi injections performed the same day, 18 patients with either abnormal 201 Tl myocardial scan or abnormal coronary angiography were studied with 2 99m Tc-hexamibi injections protocols. The rest-stress study was performed as follows: 7 mCi 99m Tc-hexamibi was injected at rest. Single photon emission computed tomography (SPECT) was performed 60 min later. Immediately after the rest study, patients were injected at peak stress with 25 mCi 99m Tc-hexamibi. Tomographic imaging was repeated 1 h later. Patients were submitted to the stress-rest protocol within 3 days. Tomographic imaging was done 1 h after a 7 mCi injection at stress. This study was followed by an injection of 25 mCi 99m Tc-hexamibi at rest, a tomographic study was performed 60 min later. Myocardial sections were reconstructed in horizontal long, vertical long, and short axes. Data analysis also included polar map representation. A total of 324 segments were interpreted blind by 3 observers, there was an agreement in 283/324 (87.3%) segments between the 2 protocols. However, 24 segments (7.4%) judged ischemic on rest-stress were called scars on stress-rest. In three patients, myocardial segments were judged normal on the rest image of the rest-stress protocol while they were found abnormal (false positive images) on the stress-rest sequence. Stress images from both protocols were judged similar in 17 patients. In conclusion, when using a short time interval (less than 2 h) between two 99m Tc-hexamibi injections, it is preferable to do a rest-stress sequence since the rest image performed initially represents a true rest study, which is not necessarily the case with the stress-rest sequence

Resting technetium-99m methoxyisobutylisonitrile cardiac imaging in chronic coronary artery disease: comparison with rest-redistribution thallium-201 scintigraphy

International Nuclear Information System (INIS)

Cuocolo, A.; Maurea, S.; Pace, L.; Nicolai, E.; Nappi, A.; Imbriaco, M.; Trimarco, B.; Salvatore, M.

1993-01-01

We studied 19 patients with angiographically proven coronary artery disease and left ventricular dysfunction (ejection fraction 33%±8%) by resting technetium-99m methoxyisobutylisonitrile ( 99m Tc-MIBI) and rest-redistribution thallium-201 cardiac imaging. Thallium and 99m Tc-MIBI studies were visually analysed. Of 285 segments, 203 (71%) had normal thallium uptake, 48 (17%) showed reversible thallium defects and 34 (12%) showed irreversible thallium defects. Of these 34 irreversible thallium defects, 19 (56%) were moderate and 15 (44%) were severe. Of the corresponding 285 segments, 200 (70%) had normal 99m Tc-MIBI uptake, while 37 (13%) showed moderate and 48 (17%) showed severe reduction of MIBI uptake. Myocardial segmental agreement for regional uptake score between initial thallium and resting 99m Tc-MIBI images was 90% (κ=0.78). Segmental agreement between delayed thallium and resting 99m Tc-MIBI images was 77% (κ=0.44). In particular, in 26 (9%) segments 99m Tc-MIBI uptake was severely reduced while delayed thallium uptake was normal or only moderately reduced. These data suggest that although rest-redistribution thallium and resting 99m Tc-MIBI cardiac imaging provide concordant results in the majority of myocardial segments, some segments with severely reduced resting 99m Tc-MIBI uptake may contain viable but hypoperfused myocardium. Thus, conclusions on myocardial viability based on 99m Tc-MIBI uptake should be made with caution in chronic coronary artery disease. (orig.)

Female thermal sensitivity to hot and cold during rest and exercise.

Science.gov (United States)

Gerrett, Nicola; Ouzzahra, Yacine; Redortier, Bernard; Voelcker, Thomas; Havenith, George

2015-12-01

Regional differences in thermal sensation to a hot or cold stimulus are often limited to male participants, in a rested state and cover minimal locations. Therefore, magnitude sensation to both a hot and cold stimulus were investigated during rest and exercise in 8 females (age: 20.4 ± 1.4 years, mass: 61.7 ± 4.0 kg, height: 166.9 ± 5.4 cm, VO2max: 36.8 ± 4.5 ml·kg(-1)·min(-1)). Using a repeated measures cross over design, participants rested in a stable environment (22.3 ± 0.9°C, 37.7 ± 5.5% RH) whilst a thermal probe (25 cm(2)), set at either 40°C or 20°C, was applied in a balanced order to 29 locations across the body. Participants reported their thermal sensation after 10s of application. Following this, participants cycled at 50% VO2max for 20 min and then 30% VO2max whilst the sensitivity test was repeated. Females experienced significantly stronger magnitude sensations to the cold than the hot stimulus (5.5 ± 1.7 and 4.3 ± 1.3, pcold stimulation (psensation was greatest at the head then the torso and declined towards the extremities. No significant effect of location was found in response to the hot stimulation and the pattern across the body was more homogenous. In comparison to rest, exercise caused a significant overall reduction in thermal sensation (5.2 ± 1.5 and 4.6 ± 1.7, respectively, p<0.05). Body maps were produced for both stimuli during rest and exercise, which highlight sensitive areas across the body. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

The relation between resting state connectivity and creativity in adolescents before and after training

NARCIS (Netherlands)

Cousijn, Janna; Zanolie, Kiki; Munsters, Robbert J M; Kleibeuker, Sietske W; Crone, Eveline A

2014-01-01

An important component of creativity is divergent thinking, which involves the ability to generate novel and useful problem solutions. In this study, we tested the relation between resting-state functional connectivity of brain areas activated during a divergent thinking task (i.e., supramarginal

Effect of scanner acoustic background noise on strict resting-state fMRI

Directory of Open Access Journals (Sweden)

C. Rondinoni

2013-04-01

Full Text Available Functional MRI (fMRI resting-state experiments are aimed at identifying brain networks that support basal brain function. Although most investigators consider a ‘resting-state' fMRI experiment with no specific external stimulation, subjects are unavoidably under heavy acoustic noise produced by the equipment. In the present study, we evaluated the influence of auditory input on the resting-state networks (RSNs. Twenty-two healthy subjects were scanned using two similar echo-planar imaging sequences in the same 3T MRI scanner: a default pulse sequence and a reduced “silent” pulse sequence. Experimental sessions consisted of two consecutive 7-min runs with noise conditions (default or silent counterbalanced across subjects. A self-organizing group independent component analysis was applied to fMRI data in order to recognize the RSNs. The insula, left middle frontal gyrus and right precentral and left inferior parietal lobules showed significant differences in the voxel-wise comparison between RSNs depending on noise condition. In the presence of low-level noise, these areas Granger-cause oscillations in RSNs with cognitive implications (dorsal attention and entorhinal, while during high noise acquisition, these connectivities are reduced or inverted. Applying low noise MR acquisitions in research may allow the detection of subtle differences of the RSNs, with implications in experimental planning for resting-state studies, data analysis, and ergonomic factors.

Effect of scanner acoustic background noise on strict resting-state fMRI.

Science.gov (United States)

Rondinoni, C; Amaro, E; Cendes, F; dos Santos, A C; Salmon, C E G

2013-04-01

Functional MRI (fMRI) resting-state experiments are aimed at identifying brain networks that support basal brain function. Although most investigators consider a 'resting-state' fMRI experiment with no specific external stimulation, subjects are unavoidably under heavy acoustic noise produced by the equipment. In the present study, we evaluated the influence of auditory input on the resting-state networks (RSNs). Twenty-two healthy subjects were scanned using two similar echo-planar imaging sequences in the same 3T MRI scanner: a default pulse sequence and a reduced "silent" pulse sequence. Experimental sessions consisted of two consecutive 7-min runs with noise conditions (default or silent) counterbalanced across subjects. A self-organizing group independent component analysis was applied to fMRI data in order to recognize the RSNs. The insula, left middle frontal gyrus and right precentral and left inferior parietal lobules showed significant differences in the voxel-wise comparison between RSNs depending on noise condition. In the presence of low-level noise, these areas Granger-cause oscillations in RSNs with cognitive implications (dorsal attention and entorhinal), while during high noise acquisition, these connectivities are reduced or inverted. Applying low noise MR acquisitions in research may allow the detection of subtle differences of the RSNs, with implications in experimental planning for resting-state studies, data analysis, and ergonomic factors.

Resting state glutamate predicts elevated pre-stimulus alpha during self-relatedness: A combined EEG-MRS study on "rest-self overlap".

Science.gov (United States)

Bai, Yu; Nakao, Takashi; Xu, Jiameng; Qin, Pengmin; Chaves, Pedro; Heinzel, Alexander; Duncan, Niall; Lane, Timothy; Yen, Nai-Shing; Tsai, Shang-Yueh; Northoff, Georg

2016-01-01

Recent studies have demonstrated neural overlap between resting state activity and self-referential processing. This "rest-self" overlap occurs especially in anterior cortical midline structures like the perigenual anterior cingulate cortex (PACC). However, the exact neurotemporal and biochemical mechanisms remain to be identified. Therefore, we conducted a combined electroencephalography (EEG)-magnetic resonance spectroscopy (MRS) study. EEG focused on pre-stimulus (e.g., prior to stimulus presentation or perception) power changes to assess the degree to which those changes can predict subjects' perception (and judgment) of subsequent stimuli as high or low self-related. MRS measured resting state concentration of glutamate, focusing on PACC. High pre-stimulus (e.g., prior to stimulus presentation or perception) alpha power significantly correlated with both perception of stimuli judged to be highly self-related and with resting state glutamate concentrations in the PACC. In sum, our results show (i) pre-stimulus (e.g., prior to stimulus presentation or perception) alpha power and resting state glutamate concentration to mediate rest-self overlap that (ii) dispose or incline subjects to assign high degrees of self-relatedness to perceptual stimuli.

Resting States Are Resting Traits – An fMRI Study of Sex Differences and Menstrual Cycle Effects in Resting State Cognitive Control Networks

OpenAIRE

Hjelmervik, Helene; Hausmann, Markus; Osnes, Berge; Westerhausen, René; Specht, Karsten

2014-01-01

To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the c...

Interferometry with particles of non-zero rest mass: topological experiments

International Nuclear Information System (INIS)

Opat, G.I.

1994-01-01

Interferometry as a space-time process is described, together with its topology. Starting from this viewpoint, a convenient unified formalism for the phase shifts which arise in particle interferometry is developed. This formalism is based on a covariant form of Hamilton's action principle and Lagrange's equations of motion. It will be shown that this Lorentz invariant formalism yields a simple perturbation theoretic expression for the general phase shift that arises in matter-wave interferometry. The Lagrangian formalism is compared with the more usual formalism based on the wave propagation vector and frequency. The resulting formalism will be used to analyse the Sagnac effect, gravitational field measurements, and several Aharonov-Bohm-like topological phase shifts. Several topological interferometric experiments using particles of non-zero rest mass are discussed. These experiments involve the use of electrons, neutrons and neutral atoms. Neutron experiments will be emphasised. 45 refs., 15 figs

Area-selective atomic layer deposition of platinum using photosensitive polyimide.

Science.gov (United States)

Vervuurt, René H J; Sharma, Akhil; Jiao, Yuqing; Kessels, Wilhelmus Erwin M M; Bol, Ageeth A

2016-10-07

Area-selective atomic layer deposition (AS-ALD) of platinum (Pt) was studied using photosensitive polyimide as a masking layer. The polyimide films were prepared by spin-coating and patterned using photolithography. AS-ALD of Pt using poly(methyl-methacrylate) (PMMA) masking layers was used as a reference. The results show that polyimide has excellent selectivity towards the Pt deposition, after 1000 ALD cycles less than a monolayer of Pt is deposited on the polyimide surface. The polyimide film could easily be removed after ALD using a hydrogen plasma, due to a combination of weakening of the polyimide resist during Pt ALD and the catalytic activity of Pt traces on the polyimide surface. Compared to PMMA for AS-ALD of Pt, polyimide has better temperature stability. This resulted in an improved uniformity of the Pt deposits and superior definition of the Pt patterns. In addition, due to the absence of reflow contamination using polyimide the nucleation phase during Pt ALD is drastically shortened. Pt patterns down to 3.5 μm were created with polyimide, a factor of ten smaller than what is possible using PMMA, at the typical Pt ALD processing temperature of 300 °C. Initial experiments indicate that after further optimization of the polyimide process Pt features down to 100 nm should be possible, which makes AS-ALD of Pt using photosensitive polyimide a promising candidate for patterning at the nanoscale.

Advances in atomic, molecular, and optical physics

CERN Document Server

Berman, Paul R; Arimondo, Ennio

2006-01-01

Volume 54 of the Advances Series contains ten contributions, covering a diversity of subject areas in atomic, molecular and optical physics. The article by Regal and Jin reviews the properties of a Fermi degenerate gas of cold potassium atoms in the crossover regime between the Bose-Einstein condensation of molecules and the condensation of fermionic atom pairs. The transition between the two regions can be probed by varying an external magnetic field. Sherson, Julsgaard and Polzik explore the manner in which light and atoms can be entangled, with applications to quantum information processing

Design considerations regarding an atomizer for multi-element electrothermal atomic absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Katskov, Dmitri A., E-mail: katskovda@tut.ac.za [Department of Chemistry, Tshwane University of Technology, Private Bag X680, Pretoria 0001 (South Africa); Sadagov, Yuri M. [All-Russian Scientific Research Institute of Optical and Physical Measurements (VNIIOFI), Ozernaya St. 46, Moscow 119361 (Russian Federation)

2011-06-15

The methodology of simultaneous multi-element electrothermal atomic absorption spectrometry (ETAAS-Electrothermal Atomic Absorption Spectrometry) stipulates rigid requirements to the design and operation of the atomizer. It must provide high degree of atomization for the group of analytes, invariant respective to the vaporization kinetics and heating ramp residence time of atoms in the absorption volume and absence of memory effects from major sample components. For the low resolution spectrometer with a continuum radiation source the reduced compared to traditional ETAAS (Electrothermal Atomic Absorption Spectrometry) sensitivity should be, at least partially, compensated by creating high density of atomic vapor in the absorption pulse. The sought-for characteristics were obtained for the 18 mm in length and 2.5 mm in internal diameter longitudinally heated graphite tube atomizer furnished with 2-4.5 mg of ring shaped carbon fiber yarn collector. The collector located next to the sampling port provides large substrate area that helps to keep the sample and its residue in the central part of the tube after drying. The collector also provides a 'platform' effect that delays the vaporization and stipulates vapor release into absorption volume having already stabilized gas temperature. Due to the shape of external surface of the tube, presence of collector and rapid (about 10 {sup o}C/ms) heating, an inverse temperature distribution along the tube is attained at the beginnings of the atomization and cleaning steps. The effect is employed for cleaning of the atomizer using the set of short maximum power heating pulses. Preparation, optimal maintenance of the atomizer and its compliance to the multi-element determination requirements are evaluated and discussed. The experimental setup provides direct simultaneous determination of large group of element within 3-4 order concentration range. Limits of detection are close to those for sequential single element

Resting site use of giant pandas in Wanglang Nature Reserve.

Science.gov (United States)

Kang, Dongwei; Wang, Xiaorong; Li, Junqing

2017-10-23

Little is known about the resting sites used by the giant panda (Ailuropoda melanoleuca), which restricts our understanding of their resting habits and limits conservation efforts. To enhance our understanding of resting site requirements and factors affecting the resting time of giant pandas, we investigated the characteristics of resting sites in the Wanglang Nature Reserve, Sichuan Province, China. The results indicated that the resting sites of giant pandas were characterised by a mean slope of 21°, mean nearest tree size of 53.75 cm, mean nearest shrub size of 2.82 cm, and mean nearest bamboo number of 56. We found that the resting sites were closer to bamboo than to trees and shrubs, suggesting that the resting site use of giant pandas is closely related to the presence of bamboo. Considering that giant pandas typically rest near a large-sized tree, protection of large trees in the forests is of considerable importance for the conservation of this species. Furthermore, slope was found to be an important factor affecting the resting time of giant pandas, as they tended to rest for a relatively longer time in sites with a smaller degree of slope.

Atomic and Molecular Interactions

International Nuclear Information System (INIS)

2002-01-01

The Gordon Research Conference (GRC) on Atomic and Molecular Interactions was held at Roger Williams University, Bristol, RI. Emphasis was placed on current unpublished research and discussion of the future target areas in this field

A resting box for outdoor sampling of adult Anopheles arabiensis in rice irrigation schemes of lower Moshi, northern Tanzania

Directory of Open Access Journals (Sweden)

Msangi Shandala

2009-04-01

Full Text Available Abstract Background Malaria vector sampling is the best method for understanding the vector dynamics and infectivity; thus, disease transmission seasonality can be established. There is a need to protecting humans involved in the sampling of disease vectors during surveillance or in control programmes. In this study, human landing catch, two cow odour baited resting boxes and an unbaited resting box were evaluated as vector sampling tools in an area with a high proportion of Anopheles arabiensis, as the major malaria vector. Methods Three resting boxes were evaluated against human landing catch. Two were baited with cow odour, while the third was unbaited. The inner parts of the boxes were covered with black cloth materials. Experiments were arranged in latin-square design. Boxes were set in the evening and left undisturbed; mosquitoes were collected at 06:00 am the next morning, while human landing catch was done overnight. Results A total of 9,558 An. arabiensis mosquitoes were collected. 17.5% (N = 1668 were collected in resting box baited with cow body odour, 42.5% (N = 4060 in resting box baited with cow urine, 15.1% (N = 1444 in unbaited resting box and 24.9% (N = 2386 were collected by human landing catch technique. In analysis, the house positions had no effect on the density of mosquitoes caught (DF = 3, F = 0.753, P = 0.387; the sampling technique had significant impact on the caught mosquitoes densities (DF = 3, F 37. 944, P Conclusion Odour-baited resting boxes have shown the possibility of replacing the existing traditional method (human landing catch for sampling malaria vectors in areas with a high proportion of An. arabiensis as malaria vectors. Further evaluations of fermented urine and longevity of the urine odour still need to be investigated.

Focal Gray Matter Plasticity as a Function of Long Duration Head-down Tilt Bed Rest

Science.gov (United States)

Koppelmans, V.; DeDios, Y. E.; Wood, S. J.; Reuter-Lorenz, P. A.; Kofman, I.; Bloomberg, J. J.; Mulavara, A. P.; Koppelmans, V.

2014-01-01

Long duration spaceflight (i.e., > or = 22 days) has been associated with changes in sensorimotor systems, resulting in difficulties that astronauts experience with posture control, locomotion, and manual control. The microgravity environment is an important causal factor for spaceflight induced sensorimotor changes. Whether these sensorimotor changes may be related to structural and functional brain changes is yet unknown. However, experimental studies revealed changes in the gray matter (GM) of the brain after simulated microgravity. Thus, it is possible that spaceflight may affect brain structure and thereby cognitive functioning and motor behavior. Long duration head-down tilt bed rest has been suggested as an exclusionary analog to study microgravity effects on the sensorimotor system. Bed rest mimics microgravity in body unloading and bodily fluid shifts. In consideration of the health and performance of crewmembers both in- and post-flight, we are conducting a prospective longitudinal 70-day bed rest study as an analog to investigate the effects of microgravity on the brain. VBM analysis revealed a progressive decrease from pre- to in- bed rest in GM volume in bilateral areas including the frontal medial cortex, the insular cortex and the caudate. Over the same time period, there was a progressive increase in GM volume in the cerebellum, occipital-, and parietal cortex, including the precuneus. The majority of these changes did not fully recover during the post-bed rest period. Analysis of lobular GM volumes obtained with BRAINS showed significantly increased volume from pre-bed rest to in-bed rest in GM of the parietal lobe and the third ventricle. Temporal GM volume at 70 days in bed rest was smaller than that at the first pre-bed rest measurement. Trend analysis showed significant positive linear and negative quadratic relationships between parietal GM and time, a positive linear relationship between third ventricle volume and time, and a negative linear

Vibration atomic layer deposition for conformal nanoparticle coating

Energy Technology Data Exchange (ETDEWEB)

Park, Suk Won; Woo Kim, Jun; Jong Choi, Hyung; Hyung Shim, Joon, E-mail: shimm@korea.ac.kr [School of Mechanical Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

2014-01-15

A vibration atomic layer deposition reactor was developed for fabricating a conformal thin-film coating on nanosize particles. In this study, atomic layer deposition of 10–15-nm-thick Al{sub 2}O{sub 3} films was conducted on a high-surface-area acetylene black powder with particle diameters of 200–250 nm. Intense vibration during the deposition resulted in the effective separation of particles, overcoming the interparticle agglomeration force and enabling effective diffusion of the precursor into the powder chunk; this phenomenon led to the formation of a conformal film coating on the nanopowder particles. It was also confirmed that the atomic layer deposition Al{sub 2}O{sub 3} films initially grew on the high-surface-area acetylene black powder particles as discrete islands, presumably because chemisorption of the precursor and water occurred only on a few sites on the high-surface-area acetylene black powder surface. Relatively sluggish growth of the films during the initial atomic layer deposition cycles was identified from composition analysis.

The NASA Bed Rest Project

Science.gov (United States)

Rhodes, Bradley; Meck, Janice

2005-01-01

NASA s National Vision for Space Exploration includes human travel beyond low earth orbit and the ultimate safe return of the crews. Crucial to fulfilling the vision is the successful and timely development of countermeasures for the adverse physiological effects on human systems caused by long term exposure to the microgravity environment. Limited access to in-flight resources for the foreseeable future increases NASA s reliance on ground-based analogs to simulate these effects of microgravity. The primary analog for human based research will be head-down bed rest. By this approach NASA will be able to evaluate countermeasures in large sample sizes, perform preliminary evaluations of proposed in-flight protocols and assess the utility of individual or combined strategies before flight resources are requested. In response to this critical need, NASA has created the Bed Rest Project at the Johnson Space Center. The Project establishes the infrastructure and processes to provide a long term capability for standardized domestic bed rest studies and countermeasure development. The Bed Rest Project design takes a comprehensive, interdisciplinary, integrated approach that reduces the resource overhead of one investigator for one campaign. In addition to integrating studies operationally relevant for exploration, the Project addresses other new Vision objectives, namely: 1) interagency cooperation with the NIH allows for Clinical Research Center (CRC) facility sharing to the benefit of both agencies, 2) collaboration with our International Partners expands countermeasure development opportunities for foreign and domestic investigators as well as promotes consistency in approach and results, 3) to the greatest degree possible, the Project also advances research by clinicians and academia alike to encourage return to earth benefits. This paper will describe the Project s top level goals, organization and relationship to other Exploration Vision Projects, implementation

RestKit for iOS standard guide

CERN Document Server

Kalapun, Taras

2013-01-01

A step-by-step, example-based guide to learning how you can link your apps and web services using RestKit.This book is for iOS developers of all levels who are interested in boosting their productivity by utilizing third party libraries and who have a willingness to learn how to build RESTful apps using the RestKit framework. A basic knowledge of Objective-C is required as well as a simple understanding of how to use CoreData.

Cognitive Rest: An Integrated Literature Review

Science.gov (United States)

Schneider, Kathleen H.

2016-01-01

Cognitive rest has been suggested as a treatment for school athletes who have sustained a concussion, but the concept has rarely been defined. The purpose of this article is to provide a comprehensive definition of cognitive rest, based on an integrative literature review. The method of synthesis was guided by Avant and Walker's concept analysis…

Morphological brain plasticity induced by musical expertise is accompanied by modulation of functional connectivity at rest.

Science.gov (United States)

Fauvel, Baptiste; Groussard, Mathilde; Chételat, Gaël; Fouquet, Marine; Landeau, Brigitte; Eustache, Francis; Desgranges, Béatrice; Platel, Hervé

2014-04-15

The aim of this study was to explore whether musical practice-related gray matter increases in brain regions are accompanied by modifications in their resting-state functional connectivity. 16 young musically experienced adults and 17 matched nonmusicians underwent an anatomical magnetic resonance imaging (MRI) and a resting-state functional MRI (rsfMRI). A whole-brain two-sample t test run on the T1-weighted structural images revealed four clusters exhibiting significant increases in gray matter (GM) volume in the musician group, located within the right posterior and middle cingulate gyrus, left superior temporal gyrus and right inferior orbitofrontal gyrus. Each cluster was used as a seed region to generate and compare whole-brain resting-state functional connectivity maps. The two clusters within the cingulate gyrus exhibited greater connectivity for musicians with the right prefrontal cortex and left temporal pole, which play a role in autobiographical and semantic memory, respectively. The cluster in the left superior temporal gyrus displayed enhanced connectivity with several language-related areas (e.g., left premotor cortex, bilateral supramarginal gyri). Finally, the cluster in the right inferior frontal gyrus displayed more synchronous activity at rest with claustrum, areas thought to play a role in binding sensory and motor information. We interpreted these findings as the consequence of repeated collaborative use in general networks supporting some of the memory, perceptual-motor and emotional features of musical practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Identification of Resting State Networks Involved in Executive Function.

Science.gov (United States)

Connolly, Joanna; McNulty, Jonathan P; Boran, Lorraine; Roche, Richard A P; Delany, David; Bokde, Arun L W

2016-06-01

The structural networks in the human brain are consistent across subjects, and this is reflected also in that functional networks across subjects are relatively consistent. These findings are not only present during performance of a goal oriented task but there are also consistent functional networks during resting state. It suggests that goal oriented activation patterns may be a function of component networks identified using resting state. The current study examines the relationship between resting state networks measured and patterns of neural activation elicited during a Stroop task. The association between the Stroop-activated networks and the resting state networks was quantified using spatial linear regression. In addition, we investigated if the degree of spatial association of resting state networks with the Stroop task may predict performance on the Stroop task. The results of this investigation demonstrated that the Stroop activated network can be decomposed into a number of resting state networks, which were primarily associated with attention, executive function, visual perception, and the default mode network. The close spatial correspondence between the functional organization of the resting brain and task-evoked patterns supports the relevance of resting state networks in cognitive function.

Virtual Resting Pd/Pa From Coronary Angiography and Blood Flow Modelling: Diagnostic Performance Against Fractional Flow Reserve.

Science.gov (United States)

Papafaklis, Michail I; Muramatsu, Takashi; Ishibashi, Yuki; Bourantas, Christos V; Fotiadis, Dimitrios I; Brilakis, Emmanouil S; Garcia-Garcia, Héctor M; Escaned, Javier; Serruys, Patrick W; Michalis, Lampros K

2018-03-01

Fractional flow reserve (FFR) has been established as a useful diagnostic tool. The distal coronary pressure to aortic pressure (Pd/Pa) ratio at rest is a simpler physiologic index but also requires the use of the pressure wire, whereas recently proposed virtual functional indices derived from coronary imaging require complex blood flow modelling and/or are time-consuming. Our aim was to test the diagnostic performance of virtual resting Pd/Pa using routine angiographic images and a simple flow model. Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by FFR. The resting Pd/Pa for each lesion was assessed by computational fluid dynamics. The discriminatory power of virtual resting Pd/Pa against FFR (reference: ≤0.80) was high (area under the receiver operator characteristic curve [AUC]: 90.5% [95% CI: 85.4-95.6%]). Diagnostic accuracy, sensitivity and specificity for the optimal virtual resting Pd/Pa cut-off (≤0.94) were 84.9%, 90.4% and 81.6%, respectively. Virtual resting Pd/Pa demonstrated superior performance (pvirtual resting Pd/Pa and FFR (r=0.69, pVirtual resting Pd/Pa using routine angiographic data and a simple flow model provides fast functional assessment of coronary lesions without requiring the pressure-wire and hyperaemia induction. The high diagnostic performance of virtual resting Pd/Pa for predicting FFR shows promise for using this simple/fast virtual index in clinical practice. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Long-Haul Truck Sleeper Heating Load Reduction Package for Rest Period Idling

Energy Technology Data Exchange (ETDEWEB)

Lustbader, Jason Aaron; Kekelia, Bidzina; Tomerlin, Jeff; Kreutzer, Cory J.; Yeakel, Skip; Adelman, Steven; Luo, Zhiming; Zehme, John

2016-04-05

Annual fuel use for sleeper cab truck rest period idling is estimated at 667 million gallons in the United States, or 6.8% of long-haul truck fuel use. Truck idling during a rest period represents zero freight efficiency and is largely done to supply accessory power for climate conditioning of the cab. The National Renewable Energy Laboratory's CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck thermal management systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In addition, if the fuel savings provide a one- to three-year payback period, fleet owners will be economically motivated to incorporate them. For candidate idle reduction technologies to be implemented by original equipment manufacturers and fleets, their effectiveness must be quantified. To address this need, several promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads. Load reduction strategies were grouped into the focus areas of solar envelope, occupant environment, conductive pathways, and efficient equipment. Technologies in each of these focus areas were investigated in collaboration with industry partners. The most promising of these technologies were then combined with the goal of exceeding a 30% reduction in HVAC loads. These technologies included 'ultra-white' paint, advanced insulation, and advanced curtain design. Previous testing showed more than a 35.7% reduction in air conditioning loads. This paper describes the overall heat transfer coefficient testing of this advanced load reduction technology package that showed more than a 43% reduction in heating load. Adding an additional layer of advanced insulation

RESTful Java web services security

CERN Document Server

Enríquez, René

2014-01-01

A sequential and easy-to-follow guide which allows you to understand the concepts related to securing web apps/services quickly and efficiently, since each topic is explained and described with the help of an example and in a step-by-step manner, helping you to easily implement the examples in your own projects. This book is intended for web application developers who use RESTful web services to power their websites. Prior knowledge of RESTful is not mandatory, but would be advisable.

Ultratrace determination of lead in whole blood using electrothermal atomization laser-excited atomic fluorescence spectrometry.

Science.gov (United States)

Wagner, E P; Smith, B W; Winefordner, J D

1996-09-15

Laser-excited atomic fluorescence has been used to detect lead that was electrothermally atomized from whole blood in a graphite furnace. A 9 kHz repetition rate copper vapor laser pumped dye laser was used to excite the lead at 283.3 nm, and the resulting atomic fluorescence was detected at 405.8 nm. No matrix modification was used other than a 1:21 dilution of the whole blood with high-purity water. Using the atomic fluorescence peak area as the analytical measure and a background correction technique based upon a simultaneous measurement of the transmitted laser intensity, excellent agreement for NIST and CDC certified whole blood reference samples was obtained with aqueous standards. A limit of detection in blood of 10 fg/mL (100 ag absolute) was achieved.

The significance of resting thallium-201 delayed SPECT for assessing viability of infarcted regions

International Nuclear Information System (INIS)

Mori, Takao; Yamabe, Hiroshi; Yoshida, Hiroyuki; Maeda, Kazumi; Fukuzaki, Hisashi

1991-01-01

Thirty-eight patients with old myocardial infarction (OMI) and 35 patients with effort angina pectoris (EAP) underwent resting thallium-201 (Tl) SPECT one week after exercise (Ex) Tl SPECT. On the basis of both resting and Ex Tl SPECT scans, OMI patients were divided into 3 groups: those who had Tl redistribution (RD) on Ex images and the same perfusion defect (PD) on both resting and Ex delayed images (n=12, Group 1); those who had a lower PD on resting delayed images than Ex delayed images (n=15, Group 2); and those who had no Tl RD on Ex images in spite of the same PD on both resting and EX delayed images (n=11, Group 3). EAP patients were divided into Group 1 (n=18) in whom no PD was seen on Ex delayed image and Group 2 (n=17) in whom PD was not seen on Ex delayed images either, but seen on resting delayed images. EX images showed higher pulmonary artery wedge pressure in Group 2 than Group 1 of both OMI and EAP patients (27±7 mmHg vs 15±6 mmHg for OMI patients; 22±6 mmHg vs 12±7 mmHg for EAP patients). For PD, Tl uptake rate on Ex initial images was higher in Group 1 than Gorup 2 of both OMI and EAP patients (63±7% vs 55±9% for OMI patients; 72±7% vs 65±9% for EAP patients). Resting delayed images for OMI patients showed the highest Tl uptake rate in Group 1 (78±7%), followed by Group 2 (74±8%) and then Group 3 (41±10%). In the group of OMI patients, the incidence of akinetic or dyskinetic wall motion on left ventriculography was the highest in Group 3 (85.7%), followed by Group 2 (52.2%) and Group 1 (24.3%). OMI patients, as well as EAP patients, had lower PD on resting delayed images than EX delayed images. Thus, severer ischemia may be associated with stress and infarcted areas may not involve viable muscle when Tl PD is decreased on resting delayed images. (N.K.)

Spatiotemporal psychopathology I: No rest for the brain's resting state activity in depression? Spatiotemporal psychopathology of depressive symptoms.

Science.gov (United States)

Northoff, Georg

2016-01-15

Despite intense neurobiological investigation in psychiatric disorders like major depressive disorder (MDD), the basic disturbance that underlies the psychopathological symptoms of MDD remains, nevertheless, unclear. Neuroimaging has focused mainly on the brain's extrinsic activity, specifically task-evoked or stimulus-induced activity, as related to the various sensorimotor, affective, cognitive, and social functions. Recently, the focus has shifted to the brain's intrinsic activity, otherwise known as its resting state activity. While various abnormalities have been observed during this activity, their meaning and significance for depression, along with its various psychopathological symptoms, are yet to be defined. Based on findings in healthy brain resting state activity and its particular spatial and temporal structure - defined in a functional and physiological sense rather than anatomical and structural - I claim that the various depressive symptoms are spatiotemporal disturbances of the resting state activity and its spatiotemporal structure. This is supported by recent findings that link ruminations and increased self-focus in depression to abnormal spatial organization of resting state activity. Analogously, affective and cognitive symptoms like anhedonia, suicidal ideation, and thought disorder can be traced to an increased focus on the past, increased past-focus as basic temporal disturbance o the resting state. Based on these findings, I conclude that the various depressive symptoms must be conceived as spatiotemporal disturbances of the brain's resting state's activity and its spatiotemporal structure. Importantly, this entails a new form of psychopathology, "Spatiotemporal Psychopathology" that directly links the brain and psyche, therefore having major diagnostic and therapeutic implications for clinical practice. Copyright © 2015 Elsevier B.V. All rights reserved.

Resting eggs in free living marine and estuarine copepods

DEFF Research Database (Denmark)

Holm, Mark Wejlemann; Kiørboe, Thomas; Brun, Philipp Georg

2018-01-01

Marine free living copepods can survive harsh periods and cope with seasonal fluctuations in environmental conditions using resting eggs (embryonic dormancy). Laboratory experiments show that temperature is the common driver for resting egg production. Hence, we hypothesize (i) that seasonal...... temperature variation, rather than variation in food abundance is the main driver for the occurrence of the resting eggs strategy in marine and estuarine copepod species; and (ii) that the thermal boundaries of the distribution determine where resting eggs are produced and whether they are produced to cope...... with warm or cold periods. We compile literature information on the occurrence of resting egg production and relate this to spatio-temporal patterns in sea surface temperature and chlorophyll a concentration obtained from satellite observations. We find that the production of resting eggs has been reported...

Cerebral Blood Flow during Rest Associates with General Intelligence and Creativity

Science.gov (United States)

Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Nagase, Tomomi; Nouchi, Rui; Kawashima, Ryuta

2011-01-01

Recently, much scientific attention has been focused on resting brain activity and its investigation through such methods as the analysis of functional connectivity during rest (the temporal correlation of brain activities in different regions). However, investigation of the magnitude of brain activity during rest has focused on the relative decrease of brain activity during a task, rather than on the absolute resting brain activity. It is thus necessary to investigate the association between cognitive factors and measures of absolute resting brain activity, such as cerebral blood flow (CBF), during rest (rest-CBF). In this study, we examined this association using multiple regression analyses. Rest-CBF was the dependent variable and the independent variables included two essential components of cognitive functions, psychometric general intelligence and creativity. CBF was measured using arterial spin labeling and there were three analyses for rest-CBF; namely mean gray matter rest-CBF, mean white matter rest-CBF, and regional rest-CBF. The results showed that mean gray and white matter rest-CBF were significantly and positively correlated with individual psychometric intelligence. Furthermore, mean white matter rest-CBF was significantly and positively correlated with creativity. After correcting the effect of mean gray matter rest-CBF the significant and positive correlation between regional rest-CBF in the perisylvian anatomical cluster that includes the left superior temporal gyrus and insula and individual psychometric intelligence was found. Also, regional rest-CBF in the precuneus was significantly and negatively correlated with individual creativity. Significance of these results of regional rest-CBF did not change when the effect of regional gray matter density was corrected. The findings showed mean and regional rest-CBF in healthy young subjects to be correlated with cognitive functions. The findings also suggest that, even in young cognitively intact

US-Japan Workshop on atomic-collision data for fusion

International Nuclear Information System (INIS)

Crandall, D.H.; Hafford, P.M.; Itikawa, Y.

1981-04-01

This report, containing abstracts of each of the presentations and discussions, includes: brief talks on the applications of atomic data in tokamaks and in inertial confinement; reviews of the specific atomic collisions projects for fusion in Japan and the United States; discussions of how the data centers operate and manner of exchanging data; brief reviews of the status of electron-ion scattering and ion-atom scattering; discussions of criteria to be used in evaluating and selecting both experimental and theoretical data in these two areas; comparisons of data selected for each of six specific collision reactions which were evaluated by both groups prior to the workshop; brief reviews of activities in the related areas of atomic structure and plasma wall interactions; and a decision to pursue a joint or collaborative compilation of recommended cross sections for oxygen ions for electron impact excitation and electron capture from atomic hydrogen

Brief wakeful resting can eliminate directed forgetting.

Science.gov (United States)

Schlichting, Andreas; Bäuml, Karl-Heinz T

2017-02-01

When cued to intentionally forget previously encoded memories, participants typically show reduced recall of the memories on a later recall test. We examined how such directed forgetting is affected by a brief period of wakeful resting between encoding and test. Encoding was followed by a "passive" wakeful resting period in which subjects heard emotionally neutral music or perceived neutral pictures, or it was followed by an "active" distraction period in which subjects were engaged in counting or calculation tasks. Whereas typical directed forgetting was present after active distraction, the forgetting was absent after wakeful resting. The findings indicate that the degree to which people can intentionally forget memories is influenced by the cognitive activity that people engage in shortly after learning takes place. The results provide first evidence on the interplay between wakeful resting and intentional forgetting.

Changes of resting cerebral activities in subacute ischemic stroke patients

Directory of Open Access Journals (Sweden)

Ping Wu

2015-01-01

Full Text Available This study aimed to detect the difference in resting cerebral activities between ischemic stroke patients and healthy participants, define the abnormal site, and provide new evidence for pathological mechanisms, clinical diagnosis, prognosis prediction and efficacy evaluation of ischemic stroke. At present, the majority of functional magnetic resonance imaging studies focus on the motor dysfunction and the acute stage of ischemic stroke. This study recruited 15 right-handed ischemic stroke patients at subacute stage (15 days to 11.5 weeks and 15 age-matched healthy participants. A resting-state functional magnetic resonance imaging scan was performed on each subject to detect cerebral activity. Regional homogeneity analysis was used to investigate the difference in cerebral activities between ischemic stroke patients and healthy participants. The results showed that the ischemic stroke patients had lower regional homogeneity in anterior cingulate and left cerebrum and higher regional homogeneity in cerebellum, left precuneus and left frontal lobe, compared with healthy participants. The experimental findings demonstrate that the areas in which regional homogeneity was different between ischemic stroke patients and healthy participants are in the cerebellum, left precuneus, left triangle inferior frontal gyrus, left inferior temporal gyrus and anterior cingulate. These locations, related to the motor, sensory and emotion areas, are likely potential targets for the neural regeneration of subacute ischemic stroke patients.

Restful Implementation of Catalogue Service for Geospatial Data Provenance

Science.gov (United States)

Jiang, L. C.; Yue, P.; Lu, X. C.

2013-10-01

Provenance, also known as lineage, is important in understanding the derivation history of data products. Geospatial data provenance helps data consumers to evaluate the quality and reliability of geospatial data. In a service-oriented environment, where data are often consumed or produced by distributed services, provenance could be managed by following the same service-oriented paradigm. The Open Geospatial Consortium (OGC) Catalogue Service for the Web (CSW) is used for the registration and query of geospatial data provenance by extending ebXML Registry Information Model (ebRIM). Recent advance of the REpresentational State Transfer (REST) paradigm has shown great promise for the easy integration of distributed resources. RESTful Web Service aims to provide a standard way for Web clients to communicate with servers based on REST principles. The existing approach for provenance catalogue service could be improved by adopting the RESTful design. This paper presents the design and implementation of a catalogue service for geospatial data provenance following RESTful architecture style. A middleware named REST Converter is added on the top of the legacy catalogue service to support a RESTful style interface. The REST Converter is composed of a resource request dispatcher and six resource handlers. A prototype service is developed to demonstrate the applicability of the approach.

The Ensembl REST API: Ensembl Data for Any Language.

Science.gov (United States)

Yates, Andrew; Beal, Kathryn; Keenan, Stephen; McLaren, William; Pignatelli, Miguel; Ritchie, Graham R S; Ruffier, Magali; Taylor, Kieron; Vullo, Alessandro; Flicek, Paul

2015-01-01

We present a Web service to access Ensembl data using Representational State Transfer (REST). The Ensembl REST server enables the easy retrieval of a wide range of Ensembl data by most programming languages, using standard formats such as JSON and FASTA while minimizing client work. We also introduce bindings to the popular Ensembl Variant Effect Predictor tool permitting large-scale programmatic variant analysis independent of any specific programming language. The Ensembl REST API can be accessed at http://rest.ensembl.org and source code is freely available under an Apache 2.0 license from http://github.com/Ensembl/ensembl-rest. © The Author 2014. Published by Oxford University Press.

Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry

Science.gov (United States)

Reddy, M.M.; Benefiel, M.A.; Claassen, H.C.

1987-01-01

Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

Volunteer Work, Religious Commitment, and Resting Pulse Rates.

Science.gov (United States)

Krause, Neal; Ironson, Gail; Hill, Peter C

2017-04-01

Research indicates that greater involvement in volunteer activities is associated with better health. We aim to contribute to this literature in two ways. First, rather than rely on self-reports of health, measured resting pulse rates serve as the dependent variable. Second, an effort is made to see if religious commitment moderates the relationship between volunteering and resting pulse rates. Data that come from a recent nationwide survey (N = 2265) suggest that volunteer work is associated with lower resting pulse rates. The results also reveal that the relationship between engaging in volunteer work and resting pulse rates improves among study participants who are more deeply committed to religion.

Atom-surface potentials and atom interferometry

International Nuclear Information System (INIS)

Babb, J.F.

1998-01-01

Long-range atom-surface potentials characterize the physics of many actual systems and are now measurable spectroscopically in deflection of atomic beams in cavities or in reflection of atoms in atomic fountains. For a ground state, spherically symmetric atom the potential varies as -1/R 3 near the wall, where R is the atom-surface distance. For asymptotically large distances the potential is weaker and goes as -1/R 4 due to retardation arising from the finite speed of light. This diminished interaction can also be interpreted as a Casimir effect. The possibility of measuring atom-surface potentials using atomic interferometry is explored. The particular cases studied are the interactions of a ground-state alkali-metal atom and a dielectric or a conducting wall. Accurate descriptions of atom-surface potentials in theories of evanescent-wave atomic mirrors and evanescent wave-guided atoms are also discussed. (author)

REST-mediated recruitment of polycomb repressor complexes in mammalian cells

DEFF Research Database (Denmark)

Dietrich, Nikolaj; Lerdrup, Mads; Landt, Eskild

2012-01-01

Polycomb Repressive Complex (PRC) 1 and PRC2 regulate genes involved in differentiation and development. However, the mechanism for how PRC1 and PRC2 are recruited to genes in mammalian cells is unclear. Here we present evidence for an interaction between the transcription factor REST, PRC1......, and increased gene expression. Genome-wide analysis of Polycomb binding in Rest¿/¿ and Eed¿/¿ mouse embryonic stem (mES) cells showed that Rest was required for PRC1 recruitment to a subset of Polycomb regulated neuronal genes. Furthermore, we found that PRC1 can be recruited to Rest binding sites independently...... of CpG islands and the H3K27Me3 mark. Surprisingly, PRC2 was frequently increased around Rest binding sites located in CpG-rich regions in the Rest¿/¿ mES cells, indicating a more complex interplay where Rest also can limit PRC2 recruitment. Therefore, we propose that Rest has context...

Bremsstrahlung in atom-atom collisions

International Nuclear Information System (INIS)

Amus'ya, M.Y.; Kuchiev, M.Y.; Solov'ev, A.V.

1985-01-01

It is shown that in the collision of a fast atom with a target atom when the frequencies are on the order of the potentials or higher, there arises bremsstrahlung comparable in intensity with the bremsstrahlung emitted by an electron with the same velocity in the field of the target atom. The mechanism by which bremsstrahlung is produced in atom-atom collisions is elucidated. Results of specific calculations of the bremsstrahlung spectra are given for α particles and helium atoms colliding with xenon

Exploring connectivity with large-scale Granger causality on resting-state functional MRI.

Science.gov (United States)

DSouza, Adora M; Abidin, Anas Z; Leistritz, Lutz; Wismüller, Axel

2017-08-01

Large-scale Granger causality (lsGC) is a recently developed, resting-state functional MRI (fMRI) connectivity analysis approach that estimates multivariate voxel-resolution connectivity. Unlike most commonly used multivariate approaches, which establish coarse-resolution connectivity by aggregating voxel time-series avoiding an underdetermined problem, lsGC estimates voxel-resolution, fine-grained connectivity by incorporating an embedded dimension reduction. We investigate application of lsGC on realistic fMRI simulations, modeling smoothing of neuronal activity by the hemodynamic response function and repetition time (TR), and empirical resting-state fMRI data. Subsequently, functional subnetworks are extracted from lsGC connectivity measures for both datasets and validated quantitatively. We also provide guidelines to select lsGC free parameters. Results indicate that lsGC reliably recovers underlying network structure with area under receiver operator characteristic curve (AUC) of 0.93 at TR=1.5s for a 10-min session of fMRI simulations. Furthermore, subnetworks of closely interacting modules are recovered from the aforementioned lsGC networks. Results on empirical resting-state fMRI data demonstrate recovery of visual and motor cortex in close agreement with spatial maps obtained from (i) visuo-motor fMRI stimulation task-sequence (Accuracy=0.76) and (ii) independent component analysis (ICA) of resting-state fMRI (Accuracy=0.86). Compared with conventional Granger causality approach (AUC=0.75), lsGC produces better network recovery on fMRI simulations. Furthermore, it cannot recover functional subnetworks from empirical fMRI data, since quantifying voxel-resolution connectivity is not possible as consequence of encountering an underdetermined problem. Functional network recovery from fMRI data suggests that lsGC gives useful insight into connectivity patterns from resting-state fMRI at a multivariate voxel-resolution. Copyright © 2017 Elsevier B.V. All

Atomic physics research with synchrotron radiation

International Nuclear Information System (INIS)

Crasemann, B.; Wuilleumier, F.

1985-01-01

This chapter discusses applications of synchrotron light in atomic and molecular physics. Use of the radiation from storage rings has expanded and lent access to new areas of absorption and photoemission spectroscopy and scattering experiments. Techniques applied in connection with synchrotron radiation are discussed including absorption spectroscopy, photoelectron spectroscopy, fluorescence spectroscopy and X-ray scattering. Problem areas that are being studied by the techniques mentioned above are discussed. Synchrotron radiation has provided the means for measuring the threshold-excitation and interference effects that signal the breakdown of the two-step model of atomic excitation/deexcitation. Synchrotron radiation provides more means of excited-state photoionization measurements

A resting-state fMRI study of obese females between pre- and postprandial states before and after bariatric surgery.

Science.gov (United States)

Wiemerslage, Lyle; Zhou, Wei; Olivo, Gaia; Stark, Julia; Hogenkamp, Pleunie S; Larsson, Elna-Marie; Sundbom, Magnus; Schiöth, Helgi B

2017-02-01

Past studies utilizing resting-state functional MRI (rsfMRI), have shown that obese humans exhibit altered activity in brain areas related to reward compared to normal-weight controls. However, to what extent bariatric surgery-induced weight loss alters resting-state brain activity in obese humans is less well-studied. Thus, we measured the fractional amplitude of low-frequency fluctuations from eyes-closed, rsfMRI in obese females (n = 11, mean age = 42 years, mean BMI = 41 kg/m 2 ) in both a pre- and postprandial state at two time points: four weeks before, and four weeks after bariatric surgery. Several brain areas showed altered resting-state activity following bariatric surgery, including the putamen, insula, cingulate, thalamus and frontal regions. Activity augmented by surgery was also dependent on prandial state. For example, in the fasted state, activity in the middle frontal and pre- and postcentral gyri was found to be decreased after surgery. In the sated state, activity within the insula was increased before, but not after surgery. Collectively, our results suggest that resting-state neural functions are rapidly affected following bariatric surgery and the associated weight loss and change in diet. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Do resting brain dynamics predict oddball evoked-potential?

Directory of Open Access Journals (Sweden)

Lee Tien-Wen

2011-11-01

Full Text Available Abstract Background The oddball paradigm is widely applied to the investigation of cognitive function in neuroscience and in neuropsychiatry. Whether cortical oscillation in the resting state can predict the elicited oddball event-related potential (ERP is still not clear. This study explored the relationship between resting electroencephalography (EEG and oddball ERPs. The regional powers of 18 electrodes across delta, theta, alpha and beta frequencies were correlated with the amplitude and latency of N1, P2, N2 and P3 components of oddball ERPs. A multivariate analysis based on partial least squares (PLS was applied to further examine the spatial pattern revealed by multiple correlations. Results Higher synchronization in the resting state, especially at the alpha spectrum, is associated with higher neural responsiveness and faster neural propagation, as indicated by the higher amplitude change of N1/N2 and shorter latency of P2. None of the resting quantitative EEG indices predict P3 latency and amplitude. The PLS analysis confirms that the resting cortical dynamics which explains N1/N2 amplitude and P2 latency does not show regional specificity, indicating a global property of the brain. Conclusions This study differs from previous approaches by relating dynamics in the resting state to neural responsiveness in the activation state. Our analyses suggest that the neural characteristics carried by resting brain dynamics modulate the earlier/automatic stage of target detection.

Correlation between the resistivity and the atomic clusters in liquid Cu-Sn alloys

Science.gov (United States)

Jia, Peng; Zhang, Jinyang; Hu, Xun; Li, Cancan; Zhao, Degang; Teng, XinYing; Yang, Cheng

2018-05-01

The liquid structure of CuxSn100-x (x = 0, 10, 20, 33, 40, 50, 60, 75, 80 and 100) alloys with atom percentage were investigated with resistivity and viscosity methods. It can be found from the resistivity data that the liquid Cu75Sn25 and Cu80Sn20 alloys had a negative temperature coefficient of resistivity (TCR), and liquid Cu75Sn25 alloy had a minimum value of -9.24 μΩ cm K-1. While the rest of liquid Cu-Sn alloys had a positive TCR. The results indicated that the Cu75Sn25 atomic clusters existed in Cu-Sn alloys. In addition, the method of calculating the percentage of Cu75Sn25 atomic clusters was established on the basis of resistivity theory and the law of conservation of mass. The Cu75Sn25 alloy had a maximum volume of the atomic clusters and a highest activation energy. The results further proved the existence of Cu75Sn25 atomic clusters. Furthermore, the correlation between the liquid structure and the resistivity was established. These results provide a useful reference for the investigation of liquid structure via the sensitive physical properties to the liquid structure.

A Transportable Gravity Gradiometer Based on Atom Interferometry

Science.gov (United States)

Yu, Nan; Thompson, Robert J.; Kellogg, James R.; Aveline, David C.; Maleki, Lute; Kohel, James M.

2010-01-01

rest frame for the trapped atoms. While still in this moving-frame molasses, the laser frequencies are further detuned from the atomic resonance (while maintaining this relative frequency shift) to cool the atom cloud's temperature to 2 K or below, corresponding to an rms velocity of less than 2 cm/s. After launch, the cold atoms undergo further state and velocity selection to prepare for atom interferometry. The atom interferometers are then realized using laser-induced stimulated Raman transitions to perform the necessary manipulations of each atom, and the resulting interferometer phase is measured using laser-induced fluorescence for state-normalized detection. More than 20 laser beams with independent controls of frequency, phase, and intensity are required for this measurement sequence. This instrument can facilitate the study of Earth's gravitational field from surface and air vehicles, as well as from space by allowing gravity mapping from a low-cost, single spacecraft mission. In addition, the operation of atom interferometer-based instruments in space offers greater sensitivity than is possible in terrestrial instruments due to the much longer interrogation times available in the microgravity environment. A space-based quantum gravity gradiometer has the potential to achieve sensitivities similar to the GRACE mission at long spatial wavelengths, and will also have resolution similar to GOCE for measurement at shorter length scales.

Developing RESTful web services with Jersey 2.0

CERN Document Server

Gulabani, Sunil

2013-01-01

The book will follow a standard tutorial approach and will teach readers how to use the Jersey API for creating RESTful web services.This book is intended for Java EE developers who are building applications on the REST architecture. This is a quick, hands-on guide for learning JAX-RS 2.0. Developers should have some knowledge about RESTful web services but it's not essential to know JAX-RS 1.0.

Biomarkers of Dose and Effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats

Science.gov (United States)

Background: Human controlled exposure studies have generally focused on subjects exposed to ozone (O3) while exercising while exposures in rats have been done at rest. We exposed resting subjects to labeled O3 (18O3, 0.4 ppm, for 2 hr) and compared O3 dose and effects with our...

Regional homogeneity, resting-state functional connectivity and amplitude of low frequency fluctuation associated with creativity measured by divergent thinking in a sex-specific manner.

Science.gov (United States)

Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Yokoyama, Ryoichi; Kotozaki, Yuka; Nakagawa, Seishu; Sekiguchi, Atsushi; Iizuka, Kunio; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Makoto Miyauchi, Carlos; Shinada, Takamitsu; Sakaki, Kohei; Nozawa, Takayuki; Ikeda, Shigeyuki; Yokota, Susumu; Daniele, Magistro; Sassa, Yuko; Kawashima, Ryuta

2017-05-15

Brain connectivity is traditionally thought to be important for creativity. Here we investigated the associations of creativity measured by divergent thinking (CMDT) with resting-state functional magnetic imaging (fMRI) measures and their sex differences. We examined these relationships in the brains of 1277 healthy young adults. Whole-brain analyses revealed a significant interaction between verbal CMDT and sex on (a) regional homogeneity within an area from the left anterior temporal lobe (b) on the resting state functional connectivity (RSFC) between the mPFC and the left inferior frontal gyrus and (c) on fractional amplitude of low frequency fluctuations (fALFF) in several distinct areas, including the precuneus and middle cingulate gyrus, left middle temporal gyrus, right middle frontal gyrus, and cerebellum. These interactions were mediated by positive correlations in females and negative correlations in males. These findings suggest that greater CMDT in females is reflected by (a) regional coherence (regional homogeneity) of brain areas responsible for representing and combining concepts as well as (b) the efficient functional connection (RSFC) between the key areas for the default state of cognitive activity and speech production, and (c) greater spontaneous neural activity (fALFF) during the resting of brain areas involved in frontal lobe functions, default cognitive activities, and language functions. Furthermore, these findings suggest that the associations between creativity and resting state brain connectivity patterns are different between males and females. Copyright © 2017 Elsevier Inc. All rights reserved.

Rest but busy: Aberrant resting-state functional connectivity of triple network model in insomnia.

Science.gov (United States)

Dong, Xiaojuan; Qin, Haixia; Wu, Taoyu; Hu, Hua; Liao, Keren; Cheng, Fei; Gao, Dong; Lei, Xu

2018-02-01

One classical hypothesis among many models to explain the etiology and maintenance of insomnia disorder (ID) is hyperarousal. Aberrant functional connectivity among resting-state large-scale brain networks may be the underlying neurological mechanisms of this hypothesis. The aim of current study was to investigate the functional network connectivity (FNC) among large-scale brain networks in patients with insomnia disorder (ID) during resting state. In the present study, the resting-state fMRI was used to evaluate whether patients with ID showed aberrant FNC among dorsal attention network (DAN), frontoparietal control network (FPC), anterior default mode network (aDMN), and posterior default mode network (pDMN) compared with healthy good sleepers (HGSs). The Pearson's correlation analysis was employed to explore whether the abnormal FNC observed in patients with ID was associated with sleep parameters, cognitive and emotional scores, and behavioral performance assessed by questionnaires and tasks. Patients with ID had worse subjective thought control ability measured by Thought Control Ability Questionnaire (TCAQ) and more negative affect than HGSs. Intriguingly, relative to HGSs, patients with ID showed a significant increase in FNC between DAN and FPC, but a significant decrease in FNC between aDMN and pDMN. Exploratory analysis in patients with ID revealed a significantly positive correlation between the DAN-FPC FNC and reaction time (RT) of psychomotor vigilance task (PVT). The current study demonstrated that even during the resting state, the task-activated and task-deactivated large-scale brain networks in insomniacs may still maintain a hyperarousal state, looking quite similar to the pattern in a task condition with external stimuli. Those results support the hyperarousal model of insomnia.

Discovering EEG resting state alterations of semantic dementia.

Science.gov (United States)

Grieder, Matthias; Koenig, Thomas; Kinoshita, Toshihiko; Utsunomiya, Keita; Wahlund, Lars-Olof; Dierks, Thomas; Nishida, Keiichiro

2016-05-01

Diagnosis of semantic dementia relies on cost-intensive MRI or PET, although resting EEG markers of other dementias have been reported. Yet the view still holds that resting EEG in patients with semantic dementia is normal. However, studies using increasingly sophisticated EEG analysis methods have demonstrated that slightest alterations of functional brain states can be detected. We analyzed the common four resting EEG microstates (A, B, C, and D) of 8 patients with semantic dementia in comparison with 8 healthy controls and 8 patients with Alzheimer's disease. Topographical differences between the groups were found in microstate classes B and C, while microstate classes A and D were comparable. The data showed that the semantic dementia group had a peculiar microstate E, but the commonly found microstate C was lacking. Furthermore, the presence of microstate E was significantly correlated with lower MMSE and language scores. Alterations in resting EEG can be found in semantic dementia. Topographical shifts in microstate C might be related to semantic memory deficits. This is the first study that discovered resting state EEG abnormality in semantic dementia. The notion that resting EEG in this dementia subtype is normal has to be revised. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Atomic molecular and optical physics

International Nuclear Information System (INIS)

Anon.

1986-01-01

Laser-assisted manufacturing and fiber-optics communications are but two of the products of atomic, molecular, and optical physics, (AMO) research. AMO physics provides theoretical and experimental methods and essential data to neighboring areas of science such as chemistry, astrophysics, condensed-matter physics, plasma physics, surface science, biology, and medicine. This book addresses advances in atomic, molecular, and optical fields and provides recommendations for further research. It also looks at scientific applications in national security, manufacturing, medicine, and other fields

A comparison of resting images from two myocardial perfusion tracers

International Nuclear Information System (INIS)

Anagnostopoulos, C.; Laney, R.; Pennell, D.; Proukakis, H.; Underwood, R.

1995-01-01

We have compared stress-redistribution and delayed rest thallium-201 with rest technetium-99m methoxyisobutylisonitrile (MIBI) tomograms in order to compare the tracers for the assessment of myocardial viability and to validate a rapid protocol combining the two tracers. We studied 30 consecutive patients with known or suspected coronary artery disease [group 1: 16 with normal left ventricular function, mean left ventricular ejection fraction (LVEF) 55%, SD 6%; group 2: 14 with abnormal function, mean LVEF 28%, SD 8%]. 201 Tl was injected during infusion of adenosine followed by acquisition of conventional stress and redistribution tomograms. On a separate day, 201 Tl was injected at rest with imaging 4 h later. 99m Tc-MIBI was then given at rest and imaging was performed. Three images were compared: redistribution 201 Tl, rest 201 Tl, and rest 99m Tc-MIBI. Tracer activity was classified visually and quantitatively in nine segments and segments with>50% activity were defined as containing clinically significant viable myocardium. Mean global tracer uptake as a percentage of maximum was similar in group 1 (rest 201 Tl 69%±12%, redistribution 201 Tl 69%±15%, rest 99m Tc-MIBI 70%±13%), but in group 2 mean tracer uptake was significantly greater in the rest 201 Tl images (59%±16%) than in redistribution 201 Tl images (53%±17%) or rest 99m Tc-MIBI images (53%±19%). Overall agreement for regional uptake score was excellent (κ from 0.79 to 0.84), although there were a significant number of segments with less uptake shown by redistribution 201 Tl and by rest 99m Tc-MIBI than by rest 201 Tl in group 2. The number of segments with significant viable myocardium in group 1 was very similar between the three images but in group 2 rest 201 Tl identified significantly more segments as viable than the other images. (orig./MG) (orig.). With 1 fig., 7 tabs

Feasibility Study of a Lunar Analog Bed Rest Model

Science.gov (United States)

Cromwell, Ronita L.; Platts, Steven H.; Yarbough, Patrice; Buccello-Stout, Regina

2010-01-01

The purpose of this study was to determine the feasibility of using a 9.5deg head-up tilt bed rest model to simulate the effects of the 1/6 g load to the human body that exists on the lunar surface. The lunar analog bed rest model utilized a modified hospital bed. The modifications included mounting the mattress on a sled that rolled on bearings to provide freedom of movement. The weight of the sled was off-loaded using a counterweight system to insure that 1/6 body weight was applied along the long axis (z-axis) of the body. Force was verified through use of a force plate mounted at the foot of the bed. A seating assembly was added to the bed to permit periods of sitting. Subjects alternated between standing and sitting positions throughout the day. A total of 35% of the day was spent in the standing position and 65% was spent sitting. In an effort to achieve physiologic fluid shifts expected for a 1/6 G environment, subjects wore compression stockings and performed unloaded foot and ankle exercises. Eight subjects (3 females and 5 males) participated in this study. Subjects spent 13 days in the pre-bed rest phase, 6 days in bed rest and 3 days post bed rest. Subjects consumed a standardized diet throughout the study. To determine feasibility, measures of subject comfort, force and plasma volume were collected. Subject comfort was assessed using a Likert scale. Subjects were asked to assess level of comfort (0-100) for 11 body regions and provide an overall rating. Results indicated minimal to no discomfort as most subjects reported scores of zero. Force measures were performed for each standing position and were validated against subject s calculated 1/6 body weight (r(sup 2) = 0.993). The carbon monoxide rebreathing technique was used to assess plasma volume during pre-bed rest and on the last day of bed rest. Plasma volume results indicated a significant decrease (p = 0.001) from pre to post bed rest values. Subjects lost on average 8.3% (sd = 6.1%) during the

WEB-SERVICE. RESTFUL ARCHITECTURE

Directory of Open Access Journals (Sweden)

M. Melnichuk

2018-04-01

Full Text Available Network technology for interaction between two applications via the HTTP protocol was considered in article.When client works with REST API - it means it works with "resources", and in SOAP work is performed with operations. To build REST web services, you must follow certain principles: explicit use of HTTP methods, access to resources by URI, stateless, HATEAOS, caching, transfer of objects in JSON or XML representation. But sometimes some principles are ignored to ensure a higher speed of work and to reduce development time.The pros and cons of using JSON and XML representations were considered, and it can be said that using the JSON format reduces the amount of data transfer, and with the use of XML, the readability of data increases.Also, two main ways of data transfer in REST web services were considered: converting the file to Base64 and transferring it as an object field or transferring the file using the usual HTTP multipart. The Base64 standard approach gives a higher speed for multiple files in a single request, because only one HTTP connection is created, but these files are stored in RAM during request processing, which increases chance of the application crashing.In the conclusion, the advantages of using web services and their wide use in other architectural approaches were considered, which increases the popularity of web services.

Single-scan rest/stress imaging: validation in a porcine model with {sup 18}F-Flurpiridaz

Energy Technology Data Exchange (ETDEWEB)

Guehl, Nicolas J.; Normandin, Marc D.; Wooten, Dustin W.; Sitek, Arkadiusk; Shoup, Timothy M.; El Fakhri, Georges; Alpert, Nathaniel M. [Harvard Medical School, Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Rozen, Guy; Ruskin, Jeremy [Harvard Medical School, Cardiac Arrhythmia Service, Department of Medicine, Massachusetts General Hospital, Boston, MA (United States); Ptaszek, Leon M. [Harvard Medical School, Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, Cardiac Arrhythmia Service, Department of Medicine, Massachusetts General Hospital, Boston, MA (United States)

2017-08-15

{sup 18}F-labeled myocardial flow agents are becoming available for clinical application but the ∝2 hour half-life of {sup 18}F complicates their clinical application for rest-stress measurements. The goal of this work is to evaluate in a pig model a single-scan method which provides quantitative rest-stress blood flow in less than 15 minutes. Single-scan rest-stress measurements were made using {sup 18}F-Flurpiridaz. Nine scans were performed in healthy pigs and seven scans were performed in injured pigs. A two-injection, single-scan protocol was used in which an adenosine infusion was started 4 minutes after the first injection of {sup 18}F-Flurpiridaz and followed either 3 or 6 minutes later by a second radiotracer injection. In two pigs, microsphere flow measurements were made at rest and during stress. Dynamic images were reoriented into the short axis view, and regions of interest (ROIs) for the 17 myocardial segments were defined in bull's eye fashion. PET data were fitted with MGH2, a kinetic model with time varying kinetic parameters, in which blood flow changes abruptly with the introduction of adenosine. Rest and stress myocardial blood flow (MBF) were estimated simultaneously. The first 12-14 minutes of rest-stress PET data were fitted in detail by the MGH2 model, yielding MBF measurement with a mean precision of 0.035 ml/min/cc. Mean myocardial blood flow across pigs was 0.61 ± 0.11 mL/min/cc at rest and 1.06 ± 0.19 mL/min/cc at stress in healthy pigs and 0.36 ± 0.20 mL/min/cc at rest and 0.62 ± 0.24 mL/min/cc at stress in the ischemic area. Good agreement was obtained with microsphere flow measurement (slope = 1.061 ± 0.017, intercept = 0.051 ± 0.017, mean difference 0.096 ± 0.18 ml/min/cc). Accurate rest and stress blood flow estimation can be obtained in less than 15 min of PET acquisition. The method is practical and easy to implement suggesting the possibility of clinical translation. (orig.)

Single-scan rest/stress imaging: validation in a porcine model with 18F-Flurpiridaz.

Science.gov (United States)

Guehl, Nicolas J; Normandin, Marc D; Wooten, Dustin W; Rozen, Guy; Sitek, Arkadiusk; Ruskin, Jeremy; Shoup, Timothy M; Ptaszek, Leon M; El Fakhri, Georges; Alpert, Nathaniel M

2017-08-01

18 F-labeled myocardial flow agents are becoming available for clinical application but the ∼2 hour half-life of 18 F complicates their clinical application for rest-stress measurements. The goal of this work is to evaluate in a pig model a single-scan method which provides quantitative rest-stress blood flow in less than 15 minutes. Single-scan rest-stress measurements were made using 18 F-Flurpiridaz. Nine scans were performed in healthy pigs and seven scans were performed in injured pigs. A two-injection, single-scan protocol was used in which an adenosine infusion was started 4 minutes after the first injection of 18 F-Flurpiridaz and followed either 3 or 6 minutes later by a second radiotracer injection. In two pigs, microsphere flow measurements were made at rest and during stress. Dynamic images were reoriented into the short axis view, and regions of interest (ROIs) for the 17 myocardial segments were defined in bull's eye fashion. PET data were fitted with MGH2, a kinetic model with time varying kinetic parameters, in which blood flow changes abruptly with the introduction of adenosine. Rest and stress myocardial blood flow (MBF) were estimated simultaneously. The first 12-14 minutes of rest-stress PET data were fitted in detail by the MGH2 model, yielding MBF measurement with a mean precision of 0.035 ml/min/cc. Mean myocardial blood flow across pigs was 0.61 ± 0.11 mL/min/cc at rest and 1.06 ± 0.19 mL/min/cc at stress in healthy pigs and 0.36 ± 0.20 mL/min/cc at rest and 0.62 ± 0.24 mL/min/cc at stress in the ischemic area. Good agreement was obtained with microsphere flow measurement (slope = 1.061 ± 0.017, intercept = 0.051 ± 0.017, mean difference 0.096 ± 0.18 ml/min/cc). Accurate rest and stress blood flow estimation can be obtained in less than 15 min of PET acquisition. The method is practical and easy to implement suggesting the possibility of clinical translation.

Correspondent Functional Topography of the Human Left Inferior Parietal Lobule at Rest and Under Task Revealed Using Resting-State fMRI and Coactivation Based Parcellation.

Science.gov (United States)

Wang, Jiaojian; Xie, Sangma; Guo, Xin; Becker, Benjamin; Fox, Peter T; Eickhoff, Simon B; Jiang, Tianzi

2017-03-01

The human left inferior parietal lobule (LIPL) plays a pivotal role in many cognitive functions and is an important node in the default mode network (DMN). Although many previous studies have proposed different parcellation schemes for the LIPL, the detailed functional organization of the LIPL and the exact correspondence between the DMN and LIPL subregions remain unclear. Mounting evidence indicates that spontaneous fluctuations in the brain are strongly associated with cognitive performance at the behavioral level. However, whether a consistent functional topographic organization of the LIPL during rest and under task can be revealed remains unknown. Here, they used resting-state functional connectivity (RSFC) and task-related coactivation patterns separately to parcellate the LIPL and identified seven subregions. Four subregions were located in the supramarginal gyrus (SMG) and three subregions were located in the angular gyrus (AG). The subregion-specific networks and functional characterization revealed that the four anterior subregions were found to be primarily involved in sensorimotor processing, movement imagination and inhibitory control, audition perception and speech processing, and social cognition, whereas the three posterior subregions were mainly involved in episodic memory, semantic processing, and spatial cognition. The results revealed a detailed functional organization of the LIPL and suggested that the LIPL is a functionally heterogeneous area. In addition, the present study demonstrated that the functional architecture of the LIPL during rest corresponds with that found in task processing. Hum Brain Mapp 38:1659-1675, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Interaction Effects of BDNF and COMT Genes on Resting-State Brain Activity and Working Memory

Science.gov (United States)

Chen, Wen; Chen, Chunhui; Xia, Mingrui; Wu, Karen; Chen, Chuansheng; He, Qinghua; Xue, Gui; Wang, Wenjing; He, Yong; Dong, Qi

2016-01-01

Catechol-O-methyltransferase (COMT) and brain-derived neurotrophic factor (BDNF) genes have been found to interactively influence working memory (WM) as well as brain activation during WM tasks. However, whether the two genes have interactive effects on resting-state activities of the brain and whether these spontaneous activations correlate with WM are still unknown. This study included behavioral data from WM tasks and genetic data (COMT rs4680 and BDNF Val66Met) from 417 healthy Chinese adults and resting-state fMRI data from 298 of them. Significant interactive effects of BDNF and COMT were found for WM performance as well as for resting-state regional homogeneity (ReHo) in WM-related brain areas, including the left medial frontal gyrus (lMeFG), left superior frontal gyrus (lSFG), right superior and medial frontal gyrus (rSMFG), right medial orbitofrontal gyrus (rMOFG), right middle frontal gyrus (rMFG), precuneus, bilateral superior temporal gyrus, left superior occipital gyrus, right middle occipital gyrus, and right inferior parietal lobule. Simple effects analyses showed that compared to other genotypes, subjects with COMT-VV/BDNF-VV had higher WM and lower ReHo in all five frontal brain areas. The results supported the hypothesis that COMT and BDNF polymorphisms influence WM performance and spontaneous brain activity (i.e., ReHo). PMID:27853425

Long-Haul Truck Sleeper Heating Load Reduction Package for Rest Period Idling: Preprint

Energy Technology Data Exchange (ETDEWEB)

Lustbader, Jason; Kekelia, Bidzina; Tomerlin, Jeff; Kreutzer, Cory; Adelman, Steve; Yeakel, Skip; Luo, Zhiming; Zehme, John

2016-03-24

Annual fuel use for sleeper cab truck rest period idling is estimated at 667 million gallons in the United States, or 6.8% of long-haul truck fuel use. Truck idling during a rest period represents zero freight efficiency and is largely done to supply accessory power for climate conditioning of the cab. The National Renewable Energy Laboratory's CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck thermal management systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In addition, if the fuel savings provide a one- to three-year payback period, fleet owners will be economically motivated to incorporate them. For candidate idle reduction technologies to be implemented by original equipment manufacturers and fleets, their effectiveness must be quantified. To address this need, several promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads. Load reduction strategies were grouped into the focus areas of solar envelope, occupant environment, conductive pathways, and efficient equipment. Technologies in each of these focus areas were investigated in collaboration with industry partners. The most promising of these technologies were then combined with the goal of exceeding a 30% reduction in HVAC loads. These technologies included 'ultra-white' paint, advanced insulation, and advanced curtain design. Previous testing showed more than a 35.7% reduction in air conditioning loads. This paper describes the overall heat transfer coefficient testing of this advanced load reduction technology package that showed more than a 43% reduction in heating load. Adding an additional layer of advanced insulation

REST represses a subset of the pancreatic endocrine differentiation program

DEFF Research Database (Denmark)

Martin, David; Kim, Yung-Hae; Sever, Dror

2015-01-01

in neurons and in endocrine cells, which is necessary for their normal function. During development, REST represses a subset of genes in the neuronal differentiation program and Rest is down-regulated as neurons differentiate. Here, we investigate the role of REST in the differentiation of pancreatic...... endocrine cells, which are molecularly close to neurons. We show that Rest is widely expressed in pancreas progenitors and that it is down-regulated in differentiated endocrine cells. Sustained expression of REST in Pdx1(+) progenitors impairs the differentiation of endocrine-committed Neurog3...

Building RESTful web services with Go learn how to build powerful RESTful APIs with Golang that scale gracefully

CERN Document Server

Yellavula, Naren

2017-01-01

REST is an architectural style that tackles the challenges of building scalable web services and in today's connected world, APIs have taken a central role on the web. APIs provide the fabric through which systems interact, and REST has become synonymous with APIs. The depth, breadth, and ease of use of Go, makes it a breeze for developers to ...

Effects of Early and Late Bilingualism on Resting-State Functional Connectivity.

Science.gov (United States)

Berken, Jonathan A; Chai, Xiaoqian; Chen, Jen-Kai; Gracco, Vincent L; Klein, Denise

2016-01-27

Of current interest is how variations in early language experience shape patterns of functional connectivity in the human brain. In the present study, we compared simultaneous (two languages from birth) and sequential (second language learned after age 5 years) bilinguals using a seed-based resting-state MRI approach. We focused on the inferior frontal gyrus (IFG) as our ROI, as recent studies have demonstrated both neurofunctional and neurostructural changes related to age of second language acquisition in bilinguals in this cortical area. Stronger functional connectivity was observed for simultaneous bilinguals between the left and right IFG, as well as between the inferior frontal gyrus and brain areas involved in language control, including the dorsolateral prefrontal cortex, inferior parietal lobule, and cerebellum. Functional connectivity between the left IFG and the right IFG and right inferior parietal lobule was also significantly correlated with age of acquisition for sequential bilinguals; the earlier the second language was acquired, the stronger was the functional connectivity. In addition, greater functional connectivity between homologous regions of the inferior frontal gyrus was associated with reduced neural activation in the left IFG during speech production. The increased connectivity at rest and reduced neural activation during task performance suggests enhanced neural efficiency in this important brain area involved in both speech production and domain-general cognitive processing. Together, our findings highlight how the brain's intrinsic functional patterns are influenced by the developmental timeline in which second language acquisition occurs. Of current interest is how early life experience leaves its footprint on brain structure and function. In this regard, bilingualism provides an optimal way to determine the effects of the timing of language learning because a second language can be learned from birth or later in life. We used resting

REST-MapReduce: An Integrated Interface but Differentiated Service

Directory of Open Access Journals (Sweden)

Jong-Hyuk Park

2014-01-01

Full Text Available With the fast deployment of cloud computing, MapReduce architectures are becoming the major technologies for mobile cloud computing. The concept of MapReduce was first introduced as a novel programming model and implementation for a large set of computing devices. In this research, we propose a novel concept of REST-MapReduce, enabling users to use only the REST interface without using the MapReduce architecture. This approach provides a higher level of abstraction by integration of the two types of access interface, REST API and MapReduce. The motivation of this research stems from the slower response time for accessing simple RDBMS on Hadoop than direct access to RDMBS. This is because there is overhead to job scheduling, initiating, starting, tracking, and management during MapReduce-based parallel execution. Therefore, we provide a good performance for REST Open API service and for MapReduce, respectively. This is very useful for constructing REST Open API services on Hadoop hosting services, for example, Amazon AWS (Macdonald, 2005 or IBM Smart Cloud. For evaluating performance of our REST-MapReduce framework, we conducted experiments with Jersey REST web server and Hadoop. Experimental result shows that our approach outperforms conventional approaches.

Non-Hermitian optics in atomic systems

Science.gov (United States)

Zhang, Zhaoyang; Ma, Danmeng; Sheng, Jiteng; Zhang, Yiqi; Zhang, Yanpeng; Xiao, Min

2018-04-01

A wide class of non-Hermitian Hamiltonians can possess entirely real eigenvalues when they have parity-time (PT) symmetric potentials. Recently, this family of non-Hermitian systems has attracted considerable attention in diverse areas of physics due to their extraordinary properties, especially in optical systems based on solid-state materials, such as coupled gain-loss waveguides and microcavities. Considering the desired refractive index can be effectively manipulated through atomic coherence, it is important to realize such non-Hermitian optical potentials and further investigate their distinct properties in atomic systems. In this paper, we review the recent theoretical and experimental progress of non-Hermitian optics with coherently prepared multi-level atomic configurations. The realizations of (anti-) PT symmetry with different schemes have extensively demonstrated the special optical properties of non-Hermitian optical systems with atomic coherence.

Laser-assisted atom-atom collisions

International Nuclear Information System (INIS)

Roussel, F.

1984-01-01

The basic layer-assisted atom-atom collision processes are reviewed in order to get a simpler picture of the main physical facts. The processes can be separated into two groups: optical collisions where only one atom is changing state during the collision, the other acting as a spectator atom, and radiative collisions where the states of the two atoms are changing during the collision. All the processes can be interpreted in terms of photoexcitation of the quasimolecule formed during the collisional process. (author)

Physics through the 1990s: Atomic, molecular, and optical physics

International Nuclear Information System (INIS)

1986-01-01

This report was prepared by the Panel on Atomic, Molecular, and Optical Physics of the Physics Survey Committee in response to its charge to describe the field, to characterize the recent advances, and to identify the current frontiers of research. Some of the areas discussed are: atomic structure, atomic dynamics, accelerator-based atomic physics, molecular photoionization and electron-molecule scattering, astrophysics, laser spectroscopy, atmospheric physics, plasma physics, and applications

The effect of 8 days of strict bed rest on the incretin effect in healthy volunteers.

Science.gov (United States)

Nielsen, Signe Tellerup; Harder-Lauridsen, Nina Majlund; Benatti, Fabiana Braga; Wedell-Neergaard, Anne-Sophie; Lyngbæk, Mark Preben; Møller, Kirsten; Pedersen, Bente Klarlund; Krogh-Madsen, Rikke

2016-03-15

Bed rest and physical inactivity are the consequences of hospital admission for many patients. Physical inactivity induces changes in glucose metabolism, but its effect on the incretin effect, which is reduced in, e.g., Type 2 diabetes, is unknown. To investigate how 8 days of strict bed rest affects the incretin effect, 10 healthy nonobese male volunteers underwent 8 days of strict bed rest. Before and after the intervention, all volunteers underwent an oral glucose tolerance test (OGTT) followed by an intravenous glucose infusion (IVGI) on the following day to mimic the blood glucose profile from the OGTT. Blood glucose, serum insulin, serum C-peptide, plasma incretin hormones [glucagon-like peptide (GLP-1) and glucose-dependent insulinotropic peptide (GIP)], and serum glucagon were measured serially during both the OGTT and the IVGI. The incretin effect is calculated as the relative difference between the area under the curve for the insulin response during the OGTT and that of the corresponding IVGI, respectively. Concentrations of glucose, insulin, C-peptide, and GIP measured during the OGTT were higher after the bed rest intervention (all P effect (P = 0.6). In conclusion, 8 days of bed rest induces insulin resistance, but we did not see evidence of an associated change in the incretin effect. Copyright © 2016 the American Physiological Society.

"Therapeutic" bed rest in pregnancy: unethical and unsupported by data.

Science.gov (United States)

McCall, Christina A; Grimes, David A; Lyerly, Anne Drapkin

2013-06-01

"Therapeutic" bed rest continues to be used widely, despite evidence of no benefit and known harms. In this commentary, we summarize the Cochrane reviews of bed rest and propose an ethical argument for discontinuing this practice. Cochrane systematic reviews do not support "therapeutic" bed rest for threatened abortion, hypertension, preeclampsia, preterm birth, multiple gestations, or impaired fetal growth. This assessment has been echoed in other comprehensive reviews. Prescribing bed rest is inconsistent with the ethical principles of autonomy, beneficence, and justice. Hence, if bed rest is to be used, it should be only within a formal clinical trial.

A REST-ful interpretation for embedded modular systems based on open architecture

Science.gov (United States)

Lyke, James

2016-05-01

The much-anticipated revolution of the "Internet of things" (IoT) is expected to generate one trillion internet devices within the next 15 years, mostly in the form of simple wireless sensor devices. While this revolution promises to transform silicon markets and drive a number of disruptive changes in society, it is also the case that the protocols, complexity, and security issues of extremely large dynamic, co-mingled networks is still poorly understood. Furthermore, embedded system developers, to include military and aerospace users, have largely ignored the potential (good and bound) of the cloudlike, possibly intermingling networks having variable structure to how future systems might be engineered. In this paper, we consider a new interpretation of IoT inspired modular architecture strategies involving the representational state transfer (REST) model, in which dynamic networks with variable structure employ stateless application programming interface (API) concepts. The power of the method, which extends concepts originally developed for space plug-and-play avionics, is that it allows for the fluid co-mingling of hardware and software in networks whose structure can overlap and evolve. Paradoxically, these systems may have the most stringent determinism and fault-tolerant needs. In this paper we review how RESTful APIs can potentially be used to design, create, test, and deploy systems rapidly while addressing security and referential integrity even when the nodes of many systems might physically co-mingle. We will also explore ways to take advantage of the RESTful paradigm for fault tolerance and what extensions might be necessary to deal with high-performance and determinism.

Resting right ventricular function is associated with exercise performance in PAH, but not in CTEPH.

Science.gov (United States)

Rehman, Michaela Beatrice; Howard, Luke S; Christiaens, Luc P; Gill, Dipender; Gibbs, J Simon R; Nihoyannopoulos, Petros

2018-02-01

To assess whether resting right ventricular (RV) function assessed by Global RV longitudinal strain (RVLS) and RV fractional area change (FAC) is associated with exercise performance in pulmonary arterial hypertension (PAH) and in chronic thromboembolic pulmonary hypertension (CTEPH). We prospectively recruited 46 consecutive patients with PAH and 42 patients with CTEPH who were referred for cardio-pulmonary exercise testing (CPET) and transthoracic echocardiography. Resting RV systolic function was assessed with RVLS and FAC. CPET parameters analyzed were percentage of predicted maximal oxygen consumption (VO2max) and the slope of ventilation against carbon dioxide production (VE/VCO2). Spearman correlation was performed between echocardiographic measurements and CPET measurements. In PAH, spearman correlation found an association between RVLS and VE/VCO2 (coefficient = 0.556, P PAH, resting RV function as assessed by FAC or RVLS is associated with exercise performance and could therefore make a significant contribution to non-invasive assessment in PAH patients. This association is not found in CTEPH, suggesting a disconnection between resting RV function and exercise performance, with implications for the use of exercise measurements as a prognostic marker and clinical/research endpoint in CTEPH. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Atom Skimmers and Atom Lasers Utilizing Them

Science.gov (United States)

Hulet, Randall; Tollett, Jeff; Franke, Kurt; Moss, Steve; Sackett, Charles; Gerton, Jordan; Ghaffari, Bita; McAlexander, W.; Strecker, K.; Homan, D.

2005-01-01

Atom skimmers are devices that act as low-pass velocity filters for atoms in thermal atomic beams. An atom skimmer operating in conjunction with a suitable thermal atomic-beam source (e.g., an oven in which cesium is heated) can serve as a source of slow atoms for a magneto-optical trap or other apparatus in an atomic-physics experiment. Phenomena that are studied in such apparatuses include Bose-Einstein condensation of atomic gases, spectra of trapped atoms, and collisions of slowly moving atoms. An atom skimmer includes a curved, low-thermal-conduction tube that leads from the outlet of a thermal atomic-beam source to the inlet of a magneto-optical trap or other device in which the selected low-velocity atoms are to be used. Permanent rare-earth magnets are placed around the tube in a yoke of high-magnetic-permeability material to establish a quadrupole or octupole magnetic field leading from the source to the trap. The atoms are attracted to the locus of minimum magnetic-field intensity in the middle of the tube, and the gradient of the magnetic field provides centripetal force that guides the atoms around the curve along the axis of the tube. The threshold velocity for guiding is dictated by the gradient of the magnetic field and the radius of curvature of the tube. Atoms moving at lesser velocities are successfully guided; faster atoms strike the tube wall and are lost from the beam.

[Creep of amalgam fillings under clasp rests].

Science.gov (United States)

Borchers, L; Jung, T; West, M

1989-10-01

A clinically realistic experiment was set up to obtain information on the amount of vertical settling of clasp rests in amalgam restorations under functional loading. Mesioocclusal cavities were prepared in 16 lower molar specimens cast in brass. The cavities were filled with amalgam and provided with a mesial rest seat. A constant load of 100 N was applied via a simplified (experimental) saddle to a cobalt-chromium E-clasp cast to the saddle. The duration of the load corresponded to 160 days of clinical function. The chronological course of vertical displacement was analyzed mathematically. According to this result the process can be divided into three components: settling immediately upon load initiation (mean value 96 microns, transition creep (mean value 25 microns) and creep ata constant rate (mean value 15 microns). The mean overall vertical displacement of the rests was 136 microns, the maximum value 287 microns. These findings suggest that vertical settling of a clasp rest into its seat in an amalgam restoration may eventually result in significant changes in occlusion and may almost completely exhaust gingival resilience.

Recovery from an acute relapse is associated with changes in motor resting-state connectivity in multiple sclerosis

DEFF Research Database (Denmark)

Dogonowski, Anne-Marie; Blinkenberg, Morten; Paulson, Olaf B.

2016-01-01

Resting-state functional MRI (rs-fMRI) of the brain has been successfully used to identify altered functional connectivity in the motor network in multiple sclerosis (MS).1 In clinically stable patients with MS, we recently demonstrated increased coupling between the basal ganglia and the motor...... network.1 Accordingly, rs-fMRI in MS is particularly suited to investigate functional reorganisation of the motor network in the remission phase after a relapse because the resting-state connectivity pattern is not influenced by interindividual differences in motor ability and task performance....... In this prospective rs-fMRI study, we mapped acute changes in resting-state motor connectivity in 12 patients with relapsing forms of MS presenting with an acute relapse involving an upper limb paresis. Previous functional MRI (fMRI) studies have shown that the activation of sensorimotor areas was stronger and more...

Increased power spectral density in resting-state pain-related brain networks in fibromyalgia.

Science.gov (United States)

Kim, Ji-Young; Kim, Seong-Ho; Seo, Jeehye; Kim, Sang-Hyon; Han, Seung Woo; Nam, Eon Jeong; Kim, Seong-Kyu; Lee, Hui Joong; Lee, Seung-Jae; Kim, Yang-Tae; Chang, Yongmin

2013-09-01

Fibromyalgia (FM), characterized by chronic widespread pain, is known to be associated with heightened responses to painful stimuli and atypical resting-state functional connectivity among pain-related regions of the brain. Previous studies of FM using resting-state functional magnetic resonance imaging (rs-fMRI) have focused on intrinsic functional connectivity, which maps the spatial distribution of temporal correlations among spontaneous low-frequency fluctuation in functional MRI (fMRI) resting-state data. In the current study, using rs-fMRI data in the frequency domain, we investigated the possible alteration of power spectral density (PSD) of low-frequency fluctuation in brain regions associated with central pain processing in patients with FM. rsfMRI data were obtained from 19 patients with FM and 20 age-matched healthy female control subjects. For each subject, the PSDs for each brain region identified from functional connectivity maps were computed for the frequency band of 0.01 to 0.25 Hz. For each group, the average PSD was determined for each brain region and a 2-sample t test was performed to determine the difference in power between the 2 groups. According to the results, patients with FM exhibited significantly increased frequency power in the primary somatosensory cortex (S1), supplementary motor area (SMA), dorsolateral prefrontal cortex, and amygdala. In patients with FM, the increase in PSD did not show an association with depression or anxiety. Therefore, our findings of atypical increased frequency power during the resting state in pain-related brain regions may implicate the enhanced resting-state baseline neural activity in several brain regions associated with pain processing in FM. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Resting-state functional connectivity abnormalities in limbic and salience networks in social anxiety disorder without comorbidity

NARCIS (Netherlands)

Pannekoek, J. Nienke; Veer, Ilya M.; van Tol, Marie-Jose; van der Werff, Steven J. A.; Demenescu, Liliana R.; Aleman, Andre; Veltman, Dick J.; Zitman, Frans G.; Rombouts, Serge A. R. B.; van der Wee, Nic J. A.

The neurobiology of social anxiety disorder (SAD) is not yet fully understood. Structural and functional neuroimaging studies in SAD have identified abnormalities in various brain areas, particularly the amygdala and elements of the salience network. This study is the first to examine resting-state

Resting-state functional connectivity abnormalities in limbic and salience networks in social anxiety disorder without comorbidity

NARCIS (Netherlands)

Pannekoek, J.N.; Veer, I.M.; van Tol, M.J.; van der Werff, S.J.A.; Demenescu, L.R.; Aleman, A.; Veltman, D.J.; Zitman, F. G.; Rombouts, S.A.R.B.; van der Wee, N.J.A.

2013-01-01

The neurobiology of social anxiety disorder (SAD) is not yet fully understood. Structural and functional neuroimaging studies in SAD have identified abnormalities in various brain areas, particularly the amygdala and elements of the salience network. This study is the first to examine resting-state

Automatic selection of resting-state networks with functional magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Silvia Francesca eStorti

2013-05-01

Full Text Available Functional magnetic resonance imaging (fMRI during a resting-state condition can reveal the co-activation of specific brain regions in distributed networks, called resting-state networks, which are selected by independent component analysis (ICA of the fMRI data. One of the major difficulties with component analysis is the automatic selection of the ICA features related to brain activity. In this study we describe a method designed to automatically select networks of potential functional relevance, specifically, those regions known to be involved in motor function, visual processing, executive functioning, auditory processing, memory, and the default-mode network. To do this, image analysis was based on probabilistic ICA as implemented in FSL software. After decomposition, the optimal number of components was selected by applying a novel algorithm which takes into account, for each component, Pearson's median coefficient of skewness of the spatial maps generated by FSL, followed by clustering, segmentation, and spectral analysis. To evaluate the performance of the approach, we investigated the resting-state networks in 25 subjects. For each subject, three resting-state scans were obtained with a Siemens Allegra 3 T scanner (NYU data set. Comparison of the visually and the automatically identified neuronal networks showed that the algorithm had high accuracy (first scan: 95%, second scan: 95%, third scan: 93% and precision (90%, 90%, 84%. The reproducibility of the networks for visual and automatic selection was very close: it was highly consistent in each subject for the default-mode network (≥ 92% and the occipital network, which includes the medial visual cortical areas (≥ 94%, and consistent for the attention network (≥ 80%, the right and/or left lateralized frontoparietal attention networks, and the temporal-motor network (≥ 80%. The automatic selection method may be used to detect neural networks and reduce subjectivity in ICA

Cardiac atrophy after bed rest and spaceflight

Science.gov (United States)

Perhonen, M. A.; Franco, F.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.; Zerwekh, J. E.; Peshock, R. M.; Weatherall, P. T.; Levine, B. D.

2001-01-01

Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically (via hypertension or valvular heart disease). If hypertension is treated, LV hypertrophy regresses, suggesting a sensitivity to LV work. However, whether physical inactivity in nonathletic populations causes adaptive changes in LV mass or even frank atrophy is not clear. We exposed previously sedentary men to 6 (n = 5) and 12 (n = 3) wk of horizontal bed rest. LV and right ventricular (RV) mass and end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, and 12 wk of bed rest; five healthy men were also studied before and after at least 6 wk of routine daily activities as controls. In addition, four astronauts were exposed to the complete elimination of hydrostatic gradients during a spaceflight of 10 days. During bed rest, LV mass decreased by 8.0 +/- 2.2% (P = 0.005) after 6 wk with an additional atrophy of 7.6 +/- 2.3% in the subjects who remained in bed for 12 wk; there was no change in LV mass for the control subjects (153.0 +/- 12.2 vs. 153.4 +/- 12.1 g, P = 0.81). Mean wall thickness decreased (4 +/- 2.5%, P = 0.01) after 6 wk of bed rest associated with the decrease in LV mass, suggesting a physiological remodeling with respect to altered load. LV end-diastolic volume decreased by 14 +/- 1.7% (P = 0.002) after 2 wk of bed rest and changed minimally thereafter. After 6 wk of bed rest, RV free wall mass decreased by 10 +/- 2.7% (P = 0.06) and RV end-diastolic volume by 16 +/- 7.9% (P = 0.06). After spaceflight, LV mass decreased by 12 +/- 6.9% (P = 0.07). In conclusion, cardiac atrophy occurs during prolonged (6 wk) horizontal bed rest and may also occur after short-term spaceflight. We suggest that cardiac atrophy is due to a physiological adaptation to reduced myocardial load and work in real or simulated microgravity and demonstrates the plasticity

Effect of mode–mode competition on atom–atom entanglement

International Nuclear Information System (INIS)

Qin, Wu; Mao-Fa, Fang; Jian-Wu, Cai

2010-01-01

A system consisting of two atoms interacting with a two-mode vacuum is considered, where each atom is resonant with the two cavity modes through two different competing transitions. The effect of mode–mode competition on the atom–atom entanglement is investigated. We find that the entanglement between the two atoms can be induced by the mode–mode competition. For the initial atomic state |Ψ(0)}, whether the atoms are initially separated or entangled, a large or even maximal entanglement between them can be obtained periodically by introducing the mode–mode competition. For the initial atomic state |Φ(0)}, the strong mode–mode competition can prevent the two atoms entangled initially from suffering entanglement sudden death; besides, it makes them in a more stable and longer-lived entanglement than in the non-competition case. (classical areas of phenomenology)

Elementary particle physics with atoms

International Nuclear Information System (INIS)

Wieman, C.E.

1993-01-01

One of the unique aspects of atomic physics is the capacity to make measurements with extraordinarily high precision. In suitably chosen systems, precision measurements can reveal information about fundamental interactions in nature that is not available from other sources. Although elementary particle physics is often perceived as synonymous with open-quotes high energyclose quotes and open-quotes high cost,close quotes atomic physics has played, and can continue to play, a significant role in this area. A few illustrative examples of this include (1) the measurement of the Lamb shift in hydrogen and its, influence on the modern development of quantum field theory, (2) the severe limits placed on possible time reversal violating interactions by atomic (and neutron) searches for electric dipole moments, and (3) the measurement (and closely related atomic theory) of parity, nonconservation in atoms. This latter work has provides a precise confirmation of the Standard Model of the weak, electromagnetic, and strong interactions, and is a uniquely sensitive test for the validity of a variety of alternative models that have been put forth. I will also discuss some of the joys and frustrations of doggedly pursuing the open-quotes ultimateclose quotes measurement of ridiculously tiny effects

Resting state brain networks in the prairie vole.

Science.gov (United States)

Ortiz, Juan J; Portillo, Wendy; Paredes, Raul G; Young, Larry J; Alcauter, Sarael

2018-01-19

Resting state functional magnetic resonance imaging (rsfMRI) has shown the hierarchical organization of the human brain into large-scale complex networks, referred as resting state networks. This technique has turned into a promising translational research tool after the finding of similar resting state networks in non-human primates, rodents and other animal models of great value for neuroscience. Here, we demonstrate and characterize the presence of resting states networks in Microtus ochrogaster, the prairie vole, an extraordinary animal model to study complex human-like social behavior, with potential implications for the research of normal social development, addiction and neuropsychiatric disorders. Independent component analysis of rsfMRI data from isoflurane-anestethized prairie voles resulted in cortical and subcortical networks, including primary motor and sensory networks, but also included putative salience and default mode networks. We further discuss how future research could help to close the gap between the properties of the large scale functional organization and the underlying neurobiology of several aspects of social cognition. These results contribute to the evidence of preserved resting state brain networks across species and provide the foundations to explore the use of rsfMRI in the prairie vole for basic and translational research.

From "rest" to language task: Task activation selects and prunes from broader resting-state network.

Science.gov (United States)

Doucet, Gaelle E; He, Xiaosong; Sperling, Michael R; Sharan, Ashwini; Tracy, Joseph I

2017-05-01

Resting-state networks (RSNs) show spatial patterns generally consistent with networks revealed during cognitive tasks. However, the exact degree of overlap between these networks has not been clearly quantified. Such an investigation shows promise for decoding altered functional connectivity (FC) related to abnormal language functioning in clinical populations such as temporal lobe epilepsy (TLE). In this context, we investigated the network configurations during a language task and during resting state using FC. Twenty-four healthy controls, 24 right and 24 left TLE patients completed a verb generation (VG) task and a resting-state fMRI scan. We compared the language network revealed by the VG task with three FC-based networks (seeding the left inferior frontal cortex (IFC)/Broca): two from the task (ON, OFF blocks) and one from the resting state. We found that, for both left TLE patients and controls, the RSN recruited regions bilaterally, whereas both VG-on and VG-off conditions produced more left-lateralized FC networks, matching more closely with the activated language network. TLE brings with it variability in both task-dependent and task-independent networks, reflective of atypical language organization. Overall, our findings suggest that our RSN captured bilateral activity, reflecting a set of prepotent language regions. We propose that this relationship can be best understood by the notion of pruning or winnowing down of the larger language-ready RSN to carry out specific task demands. Our data suggest that multiple types of network analyses may be needed to decode the association between language deficits and the underlying functional mechanisms altered by disease. Hum Brain Mapp 38:2540-2552, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Genetic radiation effects of Hiroshima and Nagasaki atomic bombs

International Nuclear Information System (INIS)

Srsen, S.

1984-01-01

A group of researchers examined persons who had survived the Hiroshima and Nagasaki bombs and were irradiated and their progeny with the aim of getting an idea of the genetic effects of these explosions. Teratogenic effects are not discussed. In the lymphocytes of the peripheral blood of persons who had been exposed to high dose irradiation the researchers found a significant increase in chromosomal aberrations by conventional and more recent methods of chromosomal analysis. In parents who had survived the atomic holocaust there were no significant deviations as against the rest of the population in still births, neonatal defects, infant mortality, and mortality of first generation progeny, in neonate weight, the sex ratio, increased occurence of leukosis and chromosomal aberrations in their children. These negative findings in the first generation do not signify that there is no danger from atomic bomb blasts for human kind. They only indicate that the effects of radiation were to small to be found by routine methods or that the methods used were not suitable

Genetic radiation effects of Hiroshima and Nagasaki atomic bombs

Energy Technology Data Exchange (ETDEWEB)

Srsen, S. (Komenskeho Univ., Bratislava (Czechoslovakia). Lekarska Fakulta)

1984-05-01

A group of researchers examined persons who had survived the Hiroshima and Nagasaki bombs and were irradiated and their progeny with the aim of getting an idea of the genetic effects of these explosions. Teratogenic effects are not discussed. In the lymphocytes of the peripheral blood of persons who had been exposed to high dose irradiation the researchers found a significant increase in chromosomal aberrations by conventional and more recent methods of chromosomal analysis. In parents who had survived the atomic holocaust there were no significant deviations as against the rest of the population in still births, neonatal defects, infant mortality, and mortality of first generation progeny, in neonate weight, the sex ratio, increased occurence of leukosis and chromosomal aberrations in their children. These negative findings in the first generation do not signify that there is no danger from atomic bomb blasts for human kind. They only indicate that the effects of radiation were too small to be found by routine methods or that the methods used were not suitable.

The evolution of the rest-frame J- and H-band luminosity function of galaxies to z=3.5

OpenAIRE

Stefanon, Mauro; Marchesini, Danilo

2011-01-01

We present the rest-frame J- and H-band luminosity function (LF) of field galaxies, based on a deep multi-wavelength composite sample from the MUSYC, FIRES and FIREWORKS survey public catalogues, covering a total area of 450 arcmin^2. The availability of flux measurements in the Spitzer IRAC 3.6, 4.5, 5.8, and 8 um channels allows us to compute absolute magnitudes in the rest-frame J and H bands up to z=3.5 minimizing the dependence on the stellar evolution models. We compute the LF in the fo...

Habenula functional resting-state connectivity in pediatric CRPS.

Science.gov (United States)

Erpelding, Nathalie; Sava, Simona; Simons, Laura E; Lebel, Alyssa; Serrano, Paul; Becerra, Lino; Borsook, David

2014-01-01

The habenula (Hb) is a small brain structure located in the posterior end of the medial dorsal thalamus and through medial (MHb) and lateral (LHb) Hb connections, it acts as a conduit of information between forebrain and brainstem structures. The role of the Hb in pain processing is well documented in animals and recently also in acute experimental pain in humans. However, its function remains unknown in chronic pain disorders. Here, we investigated Hb resting-state functional connectivity (rsFC) in patients with complex regional pain syndrome (CRPS) compared with healthy controls. Twelve pediatric patients with unilateral lower-extremity CRPS (9 females; 10-17 yr) and 12 age- and sex-matched healthy controls provided informed consent to participate in the study. In healthy controls, Hb functional connections largely overlapped with previously described anatomical connections in cortical, subcortical, and brainstem structures. Compared with controls, patients exhibited an overall Hb rsFC reduction with the rest of the brain and, specifically, with the anterior midcingulate cortex, dorsolateral prefrontal cortex, supplementary motor cortex, primary motor cortex, and premotor cortex. Our results suggest that Hb rsFC parallels anatomical Hb connections in the healthy state and that overall Hb rsFC is reduced in patients, particularly connections with forebrain areas. Patients' decreased Hb rsFC to brain regions implicated in motor, affective, cognitive, and pain inhibitory/modulatory processes may contribute to their symptomatology.

Observational Evidence for Atoms.

Science.gov (United States)

Jones, Edwin R., Jr.; Childers, Richard L.

1984-01-01

Discusses the development of the concept of atomicity and some of the many which can be used to establish its validity. Chemical evidence, evidence from crystals, Faraday's law of electrolysis, and Avogadro's number are among the areas which show how the concept originally developed from a purely philosophical idea. (JN)

Atoms

International Nuclear Information System (INIS)

Fuchs, Alain; Villani, Cedric; Guthleben, Denis; Leduc, Michele; Brenner, Anastasios; Pouthas, Joel; Perrin, Jean

2014-01-01

Completed by recent contributions on various topics (atoms and the Brownian motion, the career of Jean Perrin, the evolution of atomic physics since Jean Perrin, relationship between scientific atomism and philosophical atomism), this book is a reprint of a book published at the beginning of the twentieth century in which the author addressed the relationship between atomic theory and chemistry (molecules, atoms, the Avogadro hypothesis, molecule structures, solutes, upper limits of molecular quantities), molecular agitation (molecule velocity, molecule rotation or vibration, molecular free range), the Brownian motion and emulsions (history and general features, statistical equilibrium of emulsions), the laws of the Brownian motion (Einstein's theory, experimental control), fluctuations (the theory of Smoluchowski), light and quanta (black body, extension of quantum theory), the electricity atom, the atom genesis and destruction (transmutations, atom counting)

Doses to early entrants to the A-bombed areas and to residents of the fallout areas and 137Cs in soil of the 'black rain' area in Hiroshima

International Nuclear Information System (INIS)

Takeshita, Kenji

1976-01-01

An external exposure dose from residual activity (induced radioactivity in the fallout areas and radioactive fallout in the ''black rain'' area) caused by an atomic bomb in Hiroshima was estimated. The integrated doses to the infinite time averaged 101 rads in the atomic bombed area of Hiroshima and 32 rads in that area of Nagasaki. According to the measurement by investigators, the integrated doses of the external exposure dose due to radioactive fallout averaged 13 rads. The amount of 137 Cs in soils was determined in the southest slanting surface

RESTful web API design with Node.js

CERN Document Server

Bojinov, Valentin

2015-01-01

If you are a web developer wanting to enrich your development skills to create scalable, server-side, RESTful applications based on the Node.js platform, this book is for you. You also need to be aware of HTTP communication concepts and should have a working knowledge of JavaScript. Knowledge of REST would be an added advantage but is definitely not a necessity.

Correlation of an abnormal rest /sup 201/Tl myocardial image: Pathological findings in cardiac transplant recipients

Energy Technology Data Exchange (ETDEWEB)

McKillop, J.H.; McDougall, I.R.; Billingham, M.; Schroeder, J.S.

1982-06-01

Rest myocardial /sup 201/Tl scintigraphy was undertaken in 15 males mean age 39 years (22-54) who had been accepted for cardiac transplantation. Complete pathological correlation was obtained in 14 after transplantation and in 1 who died before a suitable donor heart became available. The average time from scintigraphy to pathological evaluation was 42 days (9-103). All the /sup 201/Tl images were grossly abnormal and on the basis of these studies it was not possible to differentiate ischemic from idiopathic cardiomyopathy. Each of the three views of the /sup 201/Tl study was divided into three segments, therefore 135 areas were available for comparison (3 x 3 x 15). Eighty-eight of these were abnormal on scan and 78 of these were abnormal pathologically. The right ventricle was seen on all rest images but the degree of uptake bore no relationship to the measured thickness of the right ventricular wall. Structures such as the atrial wall and the enlarged papillary muscle were visualized in some patients. In two patients there was an improvement of the rest /sup 201/Tl image in delayed views and histologically these areas showed a mixture of muscle and fibrous tissue. The sensitivity of /sup 201/Tl imaging in this study was 89% and there was close correlation of the images with gross and microscopic pathological findings.

Superficial shell insulation in resting and exercising men in cold water.

Science.gov (United States)

Veicsteinas, A; Ferretti, G; Rennie, D W

1982-06-01

From measurements of subcutaneous fat temperature (Tsf) at known depths below the surface, skin surface temperature (Tsk), and direct skin heat flux (H), the superficial shell isulation (Iss) of the thigh (fat + skin) was calculated as Iss (degrees C.m2.w-1) = (Tsf - Tsk)/H in nine male subjects immersed head out in a well-stirred water bath. Also, at critical water temperature (CWT = 28-33 degrees C), eight of the subjects rested for 3 h, enabling overall maximal tissue insulation (It,max) to be calculated as It,max (degrees C.m2.W-1) = (Tre - Tw)/(0.92 M +/- delta S), where Tre is rectal temperature, Tw is water temperature, M is metabolic rate, and s is loss or gain of body heat. Five subjects performed up to 2 h of mild leg cycling, preceded and followed by 60 min of rest, and both thigh Iss and overall It were measured during exercise. Iss increased from minimal values in Tw greater than 33 degrees C to maximal values (Iss,max) at CWT or below. Iss,max was linearly related to tissue thickness (d) in millimeters of fat plus skin, Iss,max (degrees C.m2.W-1) = 0.0048d-0.0052; r = 0.95, n = 37, and was not influenced by leg exercise up to a metabolic rate of 150 W.m-2 in CWT despite large increases in Tsf and H and large decreases in overall It. The slope of Iss,max vs. depth, 0.0048 degrees C.m2.W-1.mm-1, is almost identical to thermal resistivity of fat in vitro, suggesting that the superficial shell is unperfused in CWT at rest or during mild exercise. When maximal superficial shell insulation (It,ss,max) for the whole body was calculated with allowance for differing fat thicknesses and surface areas of body regions, it could account for only 10-15% of overall It,max at rest and 35-40% of overall It in mild exercise. We suggest that the poorly perfused muscle shell plays a more important role as a defense against cooling at CWT than does the superficial shell (fat + skin), particularly at rest.

Association between uncoupling protein 2, adiponectin and resting energy expenditure in obese women with normal and low resting energy expenditure.

Science.gov (United States)

Taghadomi Masoumi, Zahra; Eshraghian, Mohammad Reza; Hedayati, Mahdi; Pishva, Hamideh

2018-02-01

Obesity is recognized as the most prevalent metabolic disease worldwide. Decreases in energy expenditure may increase risk of obesity. One of the key regulators of energy balance is uncoupling protein2 (UCP2), a transporter protein presents in mitochondrial inner membrane. Moreover, adiponectin is the most abundant adipocytokine, it may play a role in energy metabolism and gene expression of UCP2. The aim of this study was to investigate potential associations between the level of uncoupling protein 2 and adiponectin and their relationship with REE (Resting Energy Expenditure) in obese women with normal and low resting energy expenditure. A total of 49 subjects (women, 25-50 years old), were included in current study, 16 subjects with BMI > 30 and low resting energy expenditure, 17 subjects with BMI > 30 and normal resting energy expenditure and 16 non-obese subjects as a control group. Anthropometric, body composition parameters and resting energy expenditure were measured. Plasma adiponectin, UCP2 protein and total protein in PBMC were determined. Measured resting energy expenditure in obese subjects with low REE was significantly lower than other groups. Plasma adiponectin in the obese subjects with low REE was significantly lower compared to normal weight group. There was a significant relationship between 'UCP2 protein/Total protein' ratio and plasma adiponectin in obese group with low REE and in three groups when we pooled. There was a significant association between REE and plasma adiponectin in three groups when we pooled. There was a significant association between plasma adiponectin and REE. Moreover, there was a significant relationship between UCP2 and REE.

Brain entropy and human intelligence: A resting-state fMRI study

Science.gov (United States)

Calderone, Daniel; Morales, Leah J.

2018-01-01

Human intelligence comprises comprehension of and reasoning about an infinitely variable external environment. A brain capable of large variability in neural configurations, or states, will more easily understand and predict variable external events. Entropy measures the variety of configurations possible within a system, and recently the concept of brain entropy has been defined as the number of neural states a given brain can access. This study investigates the relationship between human intelligence and brain entropy, to determine whether neural variability as reflected in neuroimaging signals carries information about intellectual ability. We hypothesize that intelligence will be positively associated with entropy in a sample of 892 healthy adults, using resting-state fMRI. Intelligence is measured with the Shipley Vocabulary and WASI Matrix Reasoning tests. Brain entropy was positively associated with intelligence. This relation was most strongly observed in the prefrontal cortex, inferior temporal lobes, and cerebellum. This relationship between high brain entropy and high intelligence indicates an essential role for entropy in brain functioning. It demonstrates that access to variable neural states predicts complex behavioral performance, and specifically shows that entropy derived from neuroimaging signals at rest carries information about intellectual capacity. Future work in this area may elucidate the links between brain entropy in both resting and active states and various forms of intelligence. This insight has the potential to provide predictive information about adaptive behavior and to delineate the subdivisions and nature of intelligence based on entropic patterns. PMID:29432427

Brain entropy and human intelligence: A resting-state fMRI study.

Science.gov (United States)

Saxe, Glenn N; Calderone, Daniel; Morales, Leah J

2018-01-01

Human intelligence comprises comprehension of and reasoning about an infinitely variable external environment. A brain capable of large variability in neural configurations, or states, will more easily understand and predict variable external events. Entropy measures the variety of configurations possible within a system, and recently the concept of brain entropy has been defined as the number of neural states a given brain can access. This study investigates the relationship between human intelligence and brain entropy, to determine whether neural variability as reflected in neuroimaging signals carries information about intellectual ability. We hypothesize that intelligence will be positively associated with entropy in a sample of 892 healthy adults, using resting-state fMRI. Intelligence is measured with the Shipley Vocabulary and WASI Matrix Reasoning tests. Brain entropy was positively associated with intelligence. This relation was most strongly observed in the prefrontal cortex, inferior temporal lobes, and cerebellum. This relationship between high brain entropy and high intelligence indicates an essential role for entropy in brain functioning. It demonstrates that access to variable neural states predicts complex behavioral performance, and specifically shows that entropy derived from neuroimaging signals at rest carries information about intellectual capacity. Future work in this area may elucidate the links between brain entropy in both resting and active states and various forms of intelligence. This insight has the potential to provide predictive information about adaptive behavior and to delineate the subdivisions and nature of intelligence based on entropic patterns.

Longer rest periods for intensive rotational grazing limit diet quality ...

African Journals Online (AJOL)

Longer rest periods for intensive rotational grazing limit diet quality of sheep without enhancing environmental benefits. ... This experiment was established to compare three intensive rotational grazing strategies (fast rotation [FR], average 57-day rest; slow rotation [SR], average 114-day rest; and flexible grazing [FX], based ...

Activity flow over resting-state networks shapes cognitive task activations.

Science.gov (United States)

Cole, Michael W; Ito, Takuya; Bassett, Danielle S; Schultz, Douglas H

2016-12-01

Resting-state functional connectivity (FC) has helped reveal the intrinsic network organization of the human brain, yet its relevance to cognitive task activations has been unclear. Uncertainty remains despite evidence that resting-state FC patterns are highly similar to cognitive task activation patterns. Identifying the distributed processes that shape localized cognitive task activations may help reveal why resting-state FC is so strongly related to cognitive task activations. We found that estimating task-evoked activity flow (the spread of activation amplitudes) over resting-state FC networks allowed prediction of cognitive task activations in a large-scale neural network model. Applying this insight to empirical functional MRI data, we found that cognitive task activations can be predicted in held-out brain regions (and held-out individuals) via estimated activity flow over resting-state FC networks. This suggests that task-evoked activity flow over intrinsic networks is a large-scale mechanism explaining the relevance of resting-state FC to cognitive task activations.

Atomic-scale epitaxial aluminum film on GaAs substrate

Directory of Open Access Journals (Sweden)

Yen-Ting Fan

2017-07-01

Full Text Available Atomic-scale metal films exhibit intriguing size-dependent film stability, electrical conductivity, superconductivity, and chemical reactivity. With advancing methods for preparing ultra-thin and atomically smooth metal films, clear evidences of the quantum size effect have been experimentally collected in the past two decades. However, with the problems of small-area fabrication, film oxidation in air, and highly-sensitive interfaces between the metal, substrate, and capping layer, the uses of the quantized metallic films for further ex-situ investigations and applications have been seriously limited. To this end, we develop a large-area fabrication method for continuous atomic-scale aluminum film. The self-limited oxidation of aluminum protects and quantizes the metallic film and enables ex-situ characterizations and device processing in air. Structure analysis and electrical measurements on the prepared films imply the quantum size effect in the atomic-scale aluminum film. Our work opens the way for further physics studies and device applications using the quantized electronic states in metals.

MATLAB Toolboxes for Reference Electrode Standardization Technique (REST) of Scalp EEG.

Science.gov (United States)

Dong, Li; Li, Fali; Liu, Qiang; Wen, Xin; Lai, Yongxiu; Xu, Peng; Yao, Dezhong

2017-01-01

Reference electrode standardization technique (REST) has been increasingly acknowledged and applied as a re-reference technique to transform an actual multi-channels recordings to approximately zero reference ones in electroencephalography/event-related potentials (EEG/ERPs) community around the world in recent years. However, a more easy-to-use toolbox for re-referencing scalp EEG data to zero reference is still lacking. Here, we have therefore developed two open-source MATLAB toolboxes for REST of scalp EEG. One version of REST is closely integrated into EEGLAB, which is a popular MATLAB toolbox for processing the EEG data; and another is a batch version to make it more convenient and efficient for experienced users. Both of them are designed to provide an easy-to-use for novice researchers and flexibility for experienced researchers. All versions of the REST toolboxes can be freely downloaded at http://www.neuro.uestc.edu.cn/rest/Down.html, and the detailed information including publications, comments and documents on REST can also be found from this website. An example of usage is given with comparative results of REST and average reference. We hope these user-friendly REST toolboxes could make the relatively novel technique of REST easier to study, especially for applications in various EEG studies.

Theory and applications of atomic and ionic polarizabilities

International Nuclear Information System (INIS)

Mitroy, J; Safronova, M S; Clark, Charles W

2010-01-01

Atomic polarization phenomena impinge upon a number of areas and processes in physics. The dielectric constant and refractive index of any gas are examples of macroscopic properties that are largely determined by the dipole polarizability. When it comes to microscopic phenomena, the existence of alkaline-earth anions and the recently discovered ability of positrons to bind to many atoms are predominantly due to the polarization interaction. An imperfect knowledge of atomic polarizabilities is presently looming as the largest source of uncertainty in the new generation of optical frequency standards. Accurate polarizabilities for the group I and II atoms and ions of the periodic table have recently become available by a variety of techniques. These include refined many-body perturbation theory and coupled-cluster calculations sometimes combined with precise experimental data for selected transitions, microwave spectroscopy of Rydberg atoms and ions, refractive index measurements in microwave cavities, ab initio calculations of atomic structures using explicitly correlated wavefunctions, interferometry with atom beams and velocity changes of laser cooled atoms induced by an electric field. This review examines existing theoretical methods of determining atomic and ionic polarizabilities, and discusses their relevance to various applications with particular emphasis on cold-atom physics and the metrology of atomic frequency standards. (topical review)

Theory and applications of atomic and ionic polarizabilities

Energy Technology Data Exchange (ETDEWEB)

Mitroy, J [School of Engineering, Charles Darwin University, Darwin NT 0909 (Australia); Safronova, M S [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Clark, Charles W, E-mail: jxm107@rsphysse.anu.edu.a, E-mail: msafrono@udel.ed, E-mail: charles.clark@nist.go [Joint Quantum Institute, National Institute of Standards and Technology and the University of Maryland, Gaithersburg, MD 20899-8410 (United States)

2010-10-28

Atomic polarization phenomena impinge upon a number of areas and processes in physics. The dielectric constant and refractive index of any gas are examples of macroscopic properties that are largely determined by the dipole polarizability. When it comes to microscopic phenomena, the existence of alkaline-earth anions and the recently discovered ability of positrons to bind to many atoms are predominantly due to the polarization interaction. An imperfect knowledge of atomic polarizabilities is presently looming as the largest source of uncertainty in the new generation of optical frequency standards. Accurate polarizabilities for the group I and II atoms and ions of the periodic table have recently become available by a variety of techniques. These include refined many-body perturbation theory and coupled-cluster calculations sometimes combined with precise experimental data for selected transitions, microwave spectroscopy of Rydberg atoms and ions, refractive index measurements in microwave cavities, ab initio calculations of atomic structures using explicitly correlated wavefunctions, interferometry with atom beams and velocity changes of laser cooled atoms induced by an electric field. This review examines existing theoretical methods of determining atomic and ionic polarizabilities, and discusses their relevance to various applications with particular emphasis on cold-atom physics and the metrology of atomic frequency standards. (topical review)

New trends in atomic and molecular physics advanced technological applications

CERN Document Server

2013-01-01

The field of Atomic and Molecular Physics (AMP) has reached significant advances in high–precision experimental measurement techniques. The area covers a wide spectrum ranging from conventional to new emerging multi-disciplinary areas like physics of highly charged ions (HCI), molecular physics, optical science, ultrafast laser technology etc. This book includes the important topics of atomic structure, physics of atomic collision, photoexcitation, photoionization processes, Laser cooling and trapping, Bose Einstein condensation and advanced technology applications of AMP in the fields of astronomy , astrophysics , fusion, biology and nanotechnology. This book is useful for researchers, professors, graduate, post graduate and PhD students dealing with atomic and molecular physics. The book has a wide scope with applications in neighbouring fields like plasma physics, astrophysics, cold collisions, nanotechnology and future fusion energy sources like ITER (international Thermonuclear Experimental Reactor) To...

REST based service composition

DEFF Research Database (Denmark)

Grönvall, Erik; Ingstrup, Mads; Pløger, Morten

2011-01-01

This paper presents an ongoing work developing and testing a Service Composition framework based upon the REST architecture named SECREST. A minimalistic approach have been favored instead of a creating a complete infrastructure. One focus has been on the system's interaction model. Indeed, an aim...

Resting-state functional connectivity of the default mode network associated with happiness.

Science.gov (United States)

Luo, Yangmei; Kong, Feng; Qi, Senqing; You, Xuqun; Huang, Xiting

2016-03-01

Happiness refers to people's cognitive and affective evaluation of their life. Why are some people happier than others? One reason might be that unhappy people are prone to ruminate more than happy people. The default mode network (DMN) is normally active during rest and is implicated in rumination. We hypothesized that unhappiness may be associated with increased default-mode functional connectivity during rest, including the medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC) and inferior parietal lobule (IPL). The hyperconnectivity of these areas may be associated with higher levels of rumination. One hundred forty-eight healthy participants underwent a resting-state fMRI scan. A group-independent component analysis identified the DMNs. Results indicated increased functional connectivity in the DMN was associated with lower levels of happiness. Specifically, relative to happy people, unhappy people exhibited greater functional connectivity in the anterior medial cortex (bilateral MPFC), posterior medial cortex regions (bilateral PCC) and posterior parietal cortex (left IPL). Moreover, the increased functional connectivity of the MPFC, PCC and IPL, correlated positively with the inclination to ruminate. These results highlight the important role of the DMN in the neural correlates of happiness, and suggest that rumination may play an important role in people's perceived happiness. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Innovation projects of atomic energy institute of national nuclear center RK in the area of peaceful use of atomic energy

International Nuclear Information System (INIS)

Kenzhin, E.; Tazhibayeva, I.; Vasiliyev, Y.; Kolodeshnikov, A.; Vurim, A.

2010-01-01

Institute of Atomic Energy of National Nuclear Center RK (IAE NNC RK) is located in Kurchatov. The city is situated at the border of former Semipalatinsk test site. The institute includes two reactor complexes - IGR and Baikal-1, which are rather distant from Kurchatov. Main activities of IAE NNC RK are: 1. Experimental researches of the nuclear power reactors safety; 2. Experimental researches of behavior of the structural materials for fusion and fission facilities under reactor irradiation; 3. Management of radioactive wastes; 4. Participation in the projects on decommissioning of the fast neutron reactor BN-350; 5. innovation projects: creation of first Kazakhstan's fusion reactor - tokamak KTM for materials; research and testing; development of new technologies (irradiated Be-recycling); development of new reactor technologies - project on creation of high temperature gas-cooled reactor KHTR. IAE NNC RK jointly with Japanese Atomic Energy Agency and with participation of Japanese Atomic Power Company is performing the activities on experimental substantiation of design of active core of prospective fast neutron reactor. Main goal of out-of-pile experiments at the EAGLE facility is obtaining of the information on fuel movement processes under conditions simulating the accident with melting of fast reactor core containing tube-design fuel assembly. Batch mixture is loaded into graphite crucible; then it is melded into electric melting furnace and poured into melt top trap. The outlet pipe is melted by the melt, which is poured into bottom melt trap through the pipe with sodium

Bed rest and increased diuretic treatment in chronic congestive heart failure

DEFF Research Database (Denmark)

Abildgaard, U; Aldershvile, J; Ring-Larsen, H

1985-01-01

To elucidate the effect of bed rest used as an adjunct to increased diuretic treatment, twelve patients with chronic congestive heart failure (CHF) had a 50% increase in loop diuretic dosage and were allocated to either continuous bed rest or bed rest during nights only. The 24-hour bed rest group...... is a reasonable adjunct to diuretic treatment in patients with CHF....

Resting cardiointegram: correlation with stress thallium perfusion studies

International Nuclear Information System (INIS)

Gould, L.A.; Betzu, R.; Judge, D.; Lee, J.; Taddeo, M.; Yang, D.

1988-01-01

The cardiointegram is a noninvasive technique for the analysis of the electrical signals of the heart obtained by a transformation of the voltage versus time format by a series of integrations. The stress thallium perfusion study is a widely used test for the detection of coronary artery disease. In order to evaluate the correlation between the resting cardiointegram and the stress thallium 201 perfusion study, 20 patients with normal resting electrocardiograms underwent stress thallium tests and resting cardiointegrams. The cardiointegram was determined on two resting complexes of leads I, II, V4, V5, and V6 and called abnormal if five of ten complexes deviated outside a normalized template. There was concordance of the cardiointegram and the thallium study in 16 of 20 patients (80%). The sensitivity for the detection of coronary artery disease was 71%, and the specificity was 80%. The overall accuracy was 74%. Thus in patients with normal electrocardiograms, the cardiointegram is a useful noninvasive test for the detection of coronary artery disease

Infraslow Electroencephalographic and Dynamic Resting State Network Activity.

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Grooms, Joshua K; Thompson, Garth J; Pan, Wen-Ju; Billings, Jacob; Schumacher, Eric H; Epstein, Charles M; Keilholz, Shella D

2017-06-01

A number of studies have linked the blood oxygenation level dependent (BOLD) signal to electroencephalographic (EEG) signals in traditional frequency bands (δ, θ, α, β, and γ), but the relationship between BOLD and its direct frequency correlates in the infraslow band (resting state magnetic resonance imaging data were acquired simultaneously. The DC EEG signals were correlated with the BOLD signal in patterns that resembled resting state networks. Subsequent dynamic analysis showed that the correlation between DC EEG and the BOLD signal varied substantially over time, even within individual subjects. The variation in DC EEG appears to reflect the time-varying contribution of different resting state networks. Furthermore, some of the patterns of DC EEG and BOLD correlation are consistent with previous work demonstrating quasiperiodic spatiotemporal patterns of large-scale network activity in resting state. These findings demonstrate that infraslow electrical activity is linked to BOLD fluctuations in humans and that it may provide a basis for large-scale organization comparable to that observed in animal studies.

Single-atom lasing induced atomic self-trapping

International Nuclear Information System (INIS)

Salzburger, T.; Ritsch, H.

2004-01-01

We study atomic center of mass motion and field dynamics of a single-atom laser consisting of a single incoherently pumped free atom moving in an optical high-Q resonator. For sufficient pumping, the system starts lasing whenever the atom is close to a field antinode. If the field mode eigenfrequency is larger than the atomic transition frequency, the generated laser light attracts the atom to the field antinode and cools its motion. Using quantum Monte Carlo wave function simulations, we investigate this coupled atom-field dynamics including photon recoil and cavity decay. In the regime of strong coupling, the generated field shows strong nonclassical features like photon antibunching, and the atom is spatially confined and cooled to sub-Doppler temperatures. (author)

Local activity determines functional connectivity in the resting human brain: a simultaneous FDG-PET/fMRI study.

Science.gov (United States)

Riedl, Valentin; Bienkowska, Katarzyna; Strobel, Carola; Tahmasian, Masoud; Grimmer, Timo; Förster, Stefan; Friston, Karl J; Sorg, Christian; Drzezga, Alexander

2014-04-30

Over the last decade, synchronized resting-state fluctuations of blood oxygenation level-dependent (BOLD) signals between remote brain areas [so-called BOLD resting-state functional connectivity (rs-FC)] have gained enormous relevance in systems and clinical neuroscience. However, the neural underpinnings of rs-FC are still incompletely understood. Using simultaneous positron emission tomography/magnetic resonance imaging we here directly investigated the relationship between rs-FC and local neuronal activity in humans. Computational models suggest a mechanistic link between the dynamics of local neuronal activity and the functional coupling among distributed brain regions. Therefore, we hypothesized that the local activity (LA) of a region at rest determines its rs-FC. To test this hypothesis, we simultaneously measured both LA (glucose metabolism) and rs-FC (via synchronized BOLD fluctuations) during conditions of eyes closed or eyes open. During eyes open, LA increased in the visual system, and the salience network (i.e., cingulate and insular cortices) and the pattern of elevated LA coincided almost exactly with the spatial pattern of increased rs-FC. Specifically, the voxelwise regional profile of LA in these areas strongly correlated with the regional pattern of rs-FC among the same regions (e.g., LA in primary visual cortex accounts for ∼ 50%, and LA in anterior cingulate accounts for ∼ 20% of rs-FC with the visual system). These data provide the first direct evidence in humans that local neuronal activity determines BOLD FC at rest. Beyond its relevance for the neuronal basis of coherent BOLD signal fluctuations, our procedure may translate into clinical research particularly to investigate potentially aberrant links between local dynamics and remote functional coupling in patients with neuropsychiatric disorders.

Ultracold atoms on atom chips

DEFF Research Database (Denmark)

Krüger, Peter; Hofferberth, S.; Haller, E.

2005-01-01

Miniaturized potentials near the surface of atom chips can be used as flexible and versatile tools for the manipulation of ultracold atoms on a microscale. The full scope of possibilities is only accessible if atom-surface distances can be reduced to microns. We discuss experiments in this regime...

Progress of highly charged atomic physics at IMP

International Nuclear Information System (INIS)

Ma, X; Zhu, X L; Liu, H P; Li, B; Wei, B R; Sha, S; Cao, S P; Chen, L F; Zhang, S F; Feng, W T; Zhang, D C; Qian, D B

2007-01-01

The progress of atomic physics researches at the Institute of Modern Physics (IMP) is reviewed, covering the studies on ion-atom/molecule collisions, ion-cluster interaction, negative ion formation, state-selective electron capture studied by COLTRIMS, as well as the progress of a new experimental area dedicated for atomic researches at moderate energies, and the advances of the cooler storage rings at the Heavy Ion Research Facility in Lanzhou (HIRFL). New opportunities to study collision dynamics from femto-second to atto-second regime are opened based on the present facilities and the on-going projects

Rest and the associated benefits in restorative sleep: a concept analysis.

Science.gov (United States)

Helvig, Ashley; Wade, Sonya; Hunter-Eades, Lee

2016-01-01

To report an analysis of the concept of rest. Consistency in the literature to describe the concept and use of rest is limited. Concept analysis may be advantageous in rendering an operational definition in the health care setting. This analysis is important to examine the concept of rest for structure and function to promote an understanding of the phenomenon. Rest is a vital component of restorative sleep which has implications for physical, mental and spiritual well-being. Concept analysis. A literature search was conducted in the following databases: PubMed, CINAHL, Medline, ProQuest and an online Internet search with the majority of articles published between 1995-2015. This concept analysis was implemented using the eight step approach developed by Walker and Avant. In health care, rest incorporates the cessation of activity used to promote physical and mental health. Defining attributes of rest include a pathway to calm, inner tranquillity and mental health; base of support; and stillness. Antecedents for rest are time, suitable environment and willingness. Resulting consequences include renewed physical energy, mental clarity and improved health. Rest is a concept that is used frequently in the discipline of nursing but also in various other disciplines. Rest is a basic necessity for restorative sleep to enhance well-being through the restoration of the body, mind and spirit. Defining the concept of rest in the practice of patient care is necessary for consistent use of the term in the development of holistic, patient-centred therapies. © 2015 John Wiley & Sons Ltd.

New trends in atomic and molecular physics. Advanced technological applications

International Nuclear Information System (INIS)

Mohan, Man

2013-01-01

Represents an up-to-date scientific status report on new trends in atomic and molecular physics. Multi-disciplinary approach. Also of interest to researchers in astrophysics and fusion plasma physics. Contains material important for nano- and laser technology. The field of Atomic and Molecular Physics (AMP) has reached significant advances in high-precision experimental measurement techniques. The area covers a wide spectrum ranging from conventional to new emerging multi-disciplinary areas like physics of highly charged ions (HCI), molecular physics, optical science, ultrafast laser technology etc. This book includes the important topics of atomic structure, physics of atomic collision, photoexcitation, photoionization processes, Laser cooling and trapping, Bose Einstein condensation and advanced technology applications of AMP in the fields of astronomy, astrophysics, fusion, biology and nanotechnology. This book is useful for researchers, professors, graduate, post graduate and PhD students dealing with atomic and molecular physics. The book has a wide scope with applications in neighbouring fields like plasma physics, astrophysics, cold collisions, nanotechnology and future fusion energy sources like ITER (international Thermonuclear Experimental Reactor) Tokomak plasma machine which need accurate AMP data.

Report on atomic structure research 1961-1990

International Nuclear Information System (INIS)

Fawcett, B.C.

1990-07-01

This report documents the atomic-structure research carried out during the period 1961-90. The contributions are in two main areas. The first comprises original line classifications of spectra of highly ionized atoms including identifications of a major proportion of newly observed lines in the solar far ultraviolet and soft X-ray spectrum. The second consists of theoretical calculations of atomic data such as oscillator strengths, wavelengths, energy levels and their composition. These were calculated with advanced atomic-structure codes and cover most solar abundant ions. A new method was applied to collision calculations. Research in this field, presently conducted at Rutherford Appleton Laboratory (RAL), was initiated in the United Kingdom Atomic Energy Authority (UKAEA) at Harwell in 1960. It continued under the UKAEA at Culham Laboratory in 1962 and until 1986 when staff were taken over by Science and Engineering Research Council (SERC) and later transferred to RAL in 1981. (author)

Externalities of energy and atomic power

International Nuclear Information System (INIS)

2006-09-01

Energy technology ensures not only energy supply but also has great impacts on society and environments. Economical value and effect evaluation alone doesn't mean appropriate so the evaluation of 'externalities' should be appreciated. In order to assess atomic power in this context, the Atomic Energy Society of Japan set up a research committee on 'externalities of energy and atomic power' from April 2002 to March 2006, whose activities were described in this report. In addition to environmental effects and environmental externalities, four areas were newly studied as follows: (1) biological effects of low dose rate exposure and externalities, (2) externalities as social/economical effects including stable supply and security, (3) energy technologies evaluation and (4) social choice and decision-making. (T. Tanaka)

Functional network centrality in obesity: A resting-state and task fMRI study.

Science.gov (United States)

García-García, Isabel; Jurado, María Ángeles; Garolera, Maite; Marqués-Iturria, Idoia; Horstmann, Annette; Segura, Bàrbara; Pueyo, Roser; Sender-Palacios, María José; Vernet-Vernet, Maria; Villringer, Arno; Junqué, Carme; Margulies, Daniel S; Neumann, Jane

2015-09-30

Obesity is associated with structural and functional alterations in brain areas that are often functionally distinct and anatomically distant. This suggests that obesity is associated with differences in functional connectivity of regions distributed across the brain. However, studies addressing whole brain functional connectivity in obesity remain scarce. Here, we compared voxel-wise degree centrality and eigenvector centrality between participants with obesity (n=20) and normal-weight controls (n=21). We analyzed resting state and task-related fMRI data acquired from the same individuals. Relative to normal-weight controls, participants with obesity exhibited reduced degree centrality in the right middle frontal gyrus in the resting-state condition. During the task fMRI condition, obese participants exhibited less degree centrality in the left middle frontal gyrus and the lateral occipital cortex along with reduced eigenvector centrality in the lateral occipital cortex and occipital pole. Our results highlight the central role of the middle frontal gyrus in the pathophysiology of obesity, a structure involved in several brain circuits signaling attention, executive functions and motor functions. Additionally, our analysis suggests the existence of task-dependent reduced centrality in occipital areas; regions with a role in perceptual processes and that are profoundly modulated by attention. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Time Course of Task-Specific Memory Consolidation Effects in Resting State Networks

Science.gov (United States)

Sami, Saber; Robertson, Edwin M.

2014-01-01

Previous studies have reported functionally localized changes in resting-state brain activity following a short period of motor learning, but their relationship with memory consolidation and their dependence on the form of learning is unclear. We investigate these questions with implicit or explicit variants of the serial reaction time task (SRTT). fMRI resting-state functional connectivity was measured in human subjects before the tasks, and 0.1, 0.5, and 6 h after learning. There was significant improvement in procedural skill in both groups, with the group learning under explicit conditions showing stronger initial acquisition, and greater improvement at the 6 h retest. Immediately following acquisition, this group showed enhanced functional connectivity in networks including frontal and cerebellar areas and in the visual cortex. Thirty minutes later, enhanced connectivity was observed between cerebellar nuclei, thalamus, and basal ganglia, whereas at 6 h there was enhanced connectivity in a sensory-motor cortical network. In contrast, immediately after acquisition under implicit conditions, there was increased connectivity in a network including precentral and sensory-motor areas, whereas after 30 min a similar cerebello-thalamo-basal ganglionic network was seen as in explicit learning. Finally, 6 h after implicit learning, we found increased connectivity in medial temporal cortex, but reduction in precentral and sensory-motor areas. Our findings are consistent with predictions that two variants of the SRTT task engage dissociable functional networks, although there are also networks in common. We also show a converging and diverging pattern of flux between prefrontal, sensory-motor, and parietal areas, and subcortical circuits across a 6 h consolidation period. PMID:24623776

The effects of a mid-task break on the brain connectome in healthy participants: A resting-state functional MRI study.

Science.gov (United States)

Sun, Yu; Lim, Julian; Dai, Zhongxiang; Wong, KianFoong; Taya, Fumihiko; Chen, Yu; Li, Junhua; Thakor, Nitish; Bezerianos, Anastasios

2017-05-15

Although rest breaks are commonly administered as a countermeasure to reduce mental fatigue and boost cognitive performance, the effects of taking a break on behavior are not consistent. Moreover, our understanding of the underlying neural mechanisms of rest breaks and how they modulate mental fatigue is still rudimentary. In this study, we investigated the effects of receiving a rest break on the topological properties of brain connectivity networks via a two-session experimental paradigm, in which one session comprised four successive blocks of a mentally demanding visual selective attention task (No-rest session), whereas the other contained a rest break between the second and third task blocks (Rest session). Functional brain networks were constructed using resting-state functional MRI data recorded from 20 healthy adults before and after the performance of the task blocks. Behaviorally, subjects displayed robust time-on-task (TOT) declines, as reflected by increasingly slower reaction time as the test progressed and lower post-task self-reported ratings of engagement. However, we did not find a significant effect on task performance due to administering a mid-task break. Compared to pre-task measurements, post-task functional brain networks demonstrated an overall decrease of optimal small-world properties together with lower global efficiency. Specifically, we found TOT-related reduced nodal efficiency in brain regions that mainly resided in the subcortical areas. More interestingly, a significant block-by-session interaction was revealed in local efficiency, attributing to a significant post-task decline in No-rest session and a preserved local efficiency when a mid-task break opportunity was introduced in the Rest session. Taken together, these findings augment our understanding of how the resting brain reorganizes following the accumulation of prolonged task, suggest dissociable processes between the neural mechanisms of fatigue and recovery, and provide

Characterizing Resting-State Brain Function Using Arterial Spin Labeling

Science.gov (United States)

Jann, Kay; Wang, Danny J.J.

2015-01-01

Abstract Arterial spin labeling (ASL) is an increasingly established magnetic resonance imaging (MRI) technique that is finding broader applications in studying the healthy and diseased brain. This review addresses the use of ASL to assess brain function in the resting state. Following a brief technical description, we discuss the use of ASL in the following main categories: (1) resting-state functional connectivity (FC) measurement: the use of ASL-based cerebral blood flow (CBF) measurements as an alternative to the blood oxygen level-dependent (BOLD) technique to assess resting-state FC; (2) the link between network CBF and FC measurements: the use of network CBF as a surrogate of the metabolic activity within corresponding networks; and (3) the study of resting-state dynamic CBF-BOLD coupling and cerebral metabolism: the use of dynamic CBF information obtained using ASL to assess dynamic CBF-BOLD coupling and oxidative metabolism in the resting state. In addition, we summarize some future challenges and interesting research directions for ASL, including slice-accelerated (multiband) imaging as well as the effects of motion and other physiological confounds on perfusion-based FC measurement. In summary, this work reviews the state-of-the-art of ASL and establishes it as an increasingly viable MRI technique with high translational value in studying resting-state brain function. PMID:26106930

Focal Gray Matter Plasticity as a Function of Long Duration Head Down Tilted Bed Rest: Preliminary Results

Science.gov (United States)

Koppelmans, V.; Erdeniz, B.; DeDios, Y. E.; Wood, S. J.; Reuter-Lorenz, P. A.; Kofman, I.; Bloomberg, J. J.; Mulavara, A. P.; Seidler, R. D.

2014-01-01

. Longitudinal processing in VBM8 includes linear registration of each scan to the mean of the subject and subsequently transforming all scans in to MNI space by applying the warp from the mean subject to MNI to the individual gray matter segmentations. Modulation was applied so that all images represented the volume of the original structure in native space. Voxel wise analysis was carried out on the gray matter images after smoothing, using a flexible factorial design with family wise error correction. Focal changes in white matter microstructural integrity were assessed using tract based spatial statistics (TBSS) as part of FMRIB software library (FSL). TBSS registers all DTI scans to standard space. It subsequently creates a study specific white matter skeleton of the major white matter tracts. For each subject, for each DTI metric (i.e. fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD)), the maximum value in a line perpendicular to the skeleton tract is projected to the skeleton. Non-parametric permutation based t-tests and ANOVA's were used for voxel-wise comparison of the skeletons. For both VBM and TBSS, comparison of pre bed rest measurements did not show significant differences. VBM analysis revealed decreased gray matter density in bilateral areas including the frontal medial cortex, the insular cortex and the caudate (see Figure) from 'pre to in bed rest'. Over the same time period, there was an increase in gray matter density in the cerebellum, occipital-, and parietal cortex, including the precuneus (see Figure). The majority of these changes did not recover from 'during to post bed rest'. TBSS analysis did not reveal significant changes in white matter microstructural integrity after correction for multiple comparisons. Uncorrected analyses (p<.015) revealed an increase in RD in the cerebellum and brainstem from pre bed rest to the first week in bed rest that did not recover post bed rest. Extended bed rest

Rare earth analysis in human biological samples by atomic absorption using electrothermal atomization

International Nuclear Information System (INIS)

Citron, I.M.; Holtzman, R.B.; Leiman, J.

1982-01-01

The determination of Sc and seven rare earth elements, Nd, Sm, Dy, Ho, Eu, Tm, and Yb, in biological samplesby atomic absorption spectrophotometric analysis (AAS) using electrothermal atomization in a pyrolytic graphite tube is shown to be rapid, precise and accurate. The technique utilizes the method of standard additions and linear regression analysis to determine results from peak area data. Inter-elemental interferences are negligible. The elements found sensitive enough for this type of analysis are, in order of decreasing sensitivity, Yb, Eu, Tm, Dy, Sc, Ho, Sm and Nd. The determination in these types of materials of Gd and elements less sensitive to AAS detection than Gd does not appear to be feasible. Results are presented on the concentrations of these elements in 41 samples from human subjects, cows and vegetables with normal environmental exposure to the rare earth elements. The composite percent mean deviation in peak-area readings for all samples and all elements examined was 4%. The mean standard error in the results among samples was about 6.5%

Inter-atomic interaction between electrons, 2

International Nuclear Information System (INIS)

Haga, Eijiro; Kato, Tomohiko; Aisaka, Tsuyoshi.

1978-01-01

Intra- and inter-atomic interactions in the exchange process are defined with respect to the Wannier function rather than the atomic function. In relation to the neutron scattering data for nickel, the behavior for the effective exchange parameter I(q) in the q-dependent susceptibility is, in RPA, investigated by taking into account the main types of the nearest neighbor interactions and by extending our previous treatment. The different types of interactions lead to different behavior for the q-dependence of I(q). The contribution to I(q) from inter-atomic interactions other than the exchange type decreases as the surface area of the Fermi surface becomes large. For the exchange type, the l-th neighbor interaction with l<=4 is taken into account, and, from the comparison with the empirical result for I(q), it is found that the inter-atomic contribution to I(0) is about thirty percent with a reasonable decrease against l. (author)

Resting state networks' corticotopy: the dual intertwined rings architecture.

Directory of Open Access Journals (Sweden)

Salma Mesmoudi

Full Text Available How does the brain integrate multiple sources of information to support normal sensorimotor and cognitive functions? To investigate this question we present an overall brain architecture (called "the dual intertwined rings architecture" that relates the functional specialization of cortical networks to their spatial distribution over the cerebral cortex (or "corticotopy". Recent results suggest that the resting state networks (RSNs are organized into two large families: 1 a sensorimotor family that includes visual, somatic, and auditory areas and 2 a large association family that comprises parietal, temporal, and frontal regions and also includes the default mode network. We used two large databases of resting state fMRI data, from which we extracted 32 robust RSNs. We estimated: (1 the RSN functional roles by using a projection of the results on task based networks (TBNs as referenced in large databases of fMRI activation studies; and (2 relationship of the RSNs with the Brodmann Areas. In both classifications, the 32 RSNs are organized into a remarkable architecture of two intertwined rings per hemisphere and so four rings linked by homotopic connections. The first ring forms a continuous ensemble and includes visual, somatic, and auditory cortices, with interspersed bimodal cortices (auditory-visual, visual-somatic and auditory-somatic, abbreviated as VSA ring. The second ring integrates distant parietal, temporal and frontal regions (PTF ring through a network of association fiber tracts which closes the ring anatomically and ensures a functional continuity within the ring. The PTF ring relates association cortices specialized in attention, language and working memory, to the networks involved in motivation and biological regulation and rhythms. This "dual intertwined architecture" suggests a dual integrative process: the VSA ring performs fast real-time multimodal integration of sensorimotor information whereas the PTF ring performs multi

Resting State Networks' Corticotopy: The Dual Intertwined Rings Architecture

Science.gov (United States)

Mesmoudi, Salma; Perlbarg, Vincent; Rudrauf, David; Messe, Arnaud; Pinsard, Basile; Hasboun, Dominique; Cioli, Claudia; Marrelec, Guillaume; Toro, Roberto; Benali, Habib; Burnod, Yves

2013-01-01

How does the brain integrate multiple sources of information to support normal sensorimotor and cognitive functions? To investigate this question we present an overall brain architecture (called “the dual intertwined rings architecture”) that relates the functional specialization of cortical networks to their spatial distribution over the cerebral cortex (or “corticotopy”). Recent results suggest that the resting state networks (RSNs) are organized into two large families: 1) a sensorimotor family that includes visual, somatic, and auditory areas and 2) a large association family that comprises parietal, temporal, and frontal regions and also includes the default mode network. We used two large databases of resting state fMRI data, from which we extracted 32 robust RSNs. We estimated: (1) the RSN functional roles by using a projection of the results on task based networks (TBNs) as referenced in large databases of fMRI activation studies; and (2) relationship of the RSNs with the Brodmann Areas. In both classifications, the 32 RSNs are organized into a remarkable architecture of two intertwined rings per hemisphere and so four rings linked by homotopic connections. The first ring forms a continuous ensemble and includes visual, somatic, and auditory cortices, with interspersed bimodal cortices (auditory-visual, visual-somatic and auditory-somatic, abbreviated as VSA ring). The second ring integrates distant parietal, temporal and frontal regions (PTF ring) through a network of association fiber tracts which closes the ring anatomically and ensures a functional continuity within the ring. The PTF ring relates association cortices specialized in attention, language and working memory, to the networks involved in motivation and biological regulation and rhythms. This “dual intertwined architecture” suggests a dual integrative process: the VSA ring performs fast real-time multimodal integration of sensorimotor information whereas the PTF ring performs multi

A human brain atlas derived via n-cut parcellation of resting-state and task-based fMRI data.

Science.gov (United States)

James, George Andrew; Hazaroglu, Onder; Bush, Keith A

2016-02-01

task (r=0.75-0.80) than the Random atlases (r=0.64-0.72), further validating their utility. We expected regions governing higher-order cognition (such as frontal and anterior temporal lobes) to show greatest difference between Task and Rest atlases; contrary to expectations, these areas had greatest similarity between atlases. Our findings indicate that atlases derived from parcellation of task-based and resting-state fMRI data are highly comparable, and existing resting-state atlases are suitable for task-based analyses. We introduce an anatomically labeled fMRI-derived whole-brain human atlas for future Cognitive Connectome analyses. Copyright © 2015 Elsevier Inc. All rights reserved.

Compliance and quality of life in patients on prescribed voice rest.

Science.gov (United States)

Rousseau, Bernard; Cohen, Seth M; Zeller, Amy S; Scearce, Leda; Tritter, Andrew G; Garrett, C Gaelyn

2011-01-01

To determine patient compliance with voice rest and the impact of voice rest on quality of life (QOL). Prospective. University hospital. Demographics, self-reported compliance, QOL impact on a 100-mm visual analog scale (VAS), and communication methods were collected from 84 participants from 2 academic voice centers. Of 84 participants, 36.9% were men, 63.1% were women, and 64.3% were singers. The mean age of participants was 47.2 years. The mean duration of voice rest was 8.8 days (range, 3-28), and the median was 7 days. Overall compliance was 34.5%. Postoperative voice rest patients were more compliant than non-postoperative patients (42.4% vs 16.0%, P = .04, χ(2)). Voice rest had an impact on QOL (mean ± SD, 68.5 ± 27.7). Voice rest also had a greater impact on singers than nonsingers (mean VAS 77.2 vs 63.6, P = .03, t test) and on those age <60 years than those age ≥ 60 years (mean VAS 74.4 vs 46.7, P < .001, t test). More talkative patients and those with longer periods of voice rest had worse QOL scores (Spearman correlation = 0.35, P = .001 and Spearman correlation = 0.24, P = .03, respectively). Restrictions in personal and social life were noted in 36.9% of patients, 46.4% were unable to work, 44.0% felt frustrated, and 38.1% reported feeling handicapped while on voice rest. Given poor patient compliance and the significant impact of voice rest on QOL, further studies are warranted to examine the efficacy of voice rest and factors that may contribute to patient noncompliance with treatment.

Functional connectivity of the ventral tegmental area and avolition in subjects with schizophrenia: a resting state functional MRI study.

Science.gov (United States)

Giordano, Giulia Maria; Stanziano, Mario; Papa, Michele; Mucci, Armida; Prinster, Anna; Soricelli, Andrea; Galderisi, Silvana

2018-04-10

Avolition, a deficit in goal-directed behavior, is a key aspect of negative symptoms. It is highly prevalent in schizophrenia and is associated to poor functional outcome and to measures of real life motivation, indicating that central to the concept is the lack of interest and motivation. In this study we tested the hypothesis that avolition is related to altered connectivity within dopaminergic cortico-striatal circuits involved in motivation processes. Since dopamine input to these circuits derives mostly from the ventro-tegmental area (VTA), we investigated the relationships between the resting-state functional connectivity (RS-FC) of the VTA and avolition in twenty-six subjects with schizophrenia (SCZ), treated with second-generation antipsychotics only, compared to twenty-two healthy controls (HC). SCZ, in comparison to HC, showed significantly reduced RS-FC of the VTA with bilateral ventro-lateral prefrontal cortex (VLPFC), bilateral insular cortex (IC) and right (R) lateral occipital complex (LOC) and increased RS-FC of the VTA with bilateral dorso-lateral prefrontal cortex (DLPFC). Significant negative correlations were found between avolition and RS-FC of the VTA with the bilateral IC, R VLPFC and R LOC. According to our findings, avolition is linked to a disconnectivity of the VTA from several key cortical regions involved in the integration of value information with action selection. These findings are in line with translational animal models of "auto-activation apathy". Copyright © 2018 Elsevier B.V. and ECNP. All rights reserved.

Quantitative comparisons on hand motor functional areas determined by resting state and task BOLD fMRI and anatomical MRI for pre-surgical planning of patients with brain tumors

Directory of Open Access Journals (Sweden)

Bob L. Hou

2016-01-01

Full Text Available For pre-surgical planning we present quantitative comparison of the location of the hand motor functional area determined by right hand finger tapping BOLD fMRI, resting state BOLD fMRI, and anatomically using high resolution T1 weighted images. Data were obtained on 10 healthy subjects and 25 patients with left sided brain tumors. Our results show that there are important differences in the locations (i.e., >20 mm of the determined hand motor voxels by these three MR imaging methods. This can have significant effect on the pre-surgical planning of these patients depending on the modality used. In 13 of the 25 cases (i.e., 52% the distances between the task-determined and the rs-fMRI determined hand areas were more than 20 mm; in 13 of 25 cases (i.e., 52% the distances between the task-determined and anatomically determined hand areas were >20 mm; and in 16 of 25 cases (i.e., 64% the distances between the rs-fMRI determined and anatomically determined hand areas were more than 20 mm. In just three cases, the distances determined by all three modalities were within 20 mm of each other. The differences in the location or fingerprint of the hand motor areas, as determined by these three MR methods result from the different underlying mechanisms of these three modalities and possibly the effects of tumors on these modalities.

Atoms, molecules and optical physics

CERN Document Server

Hertel, Ingolf V

2015-01-01

This is the first volume of textbooks on atomic, molecular and optical physics, aiming at a comprehensive presentation of this highly productive branch of modern physics as an indispensable basis for many areas in physics and chemistry as well as in state of the art bio- and material-sciences. It primarily addresses advanced students (including PhD students), but in a number of selected subject areas the reader is lead up to the frontiers of present research. Thus even the active scientist is addressed. This volume 1 provides the canonical knowledge in atomic physics together with basics of modern spectroscopy. Starting from the fundamentals of quantum physics, the reader is familiarized in well structured chapters step by step with the most important phenomena, models and measuring techniques. The emphasis is always on the experiment and its interpretation, while the necessary theory is introduced from this perspective in a compact and occasionally somewhat heuristic manner, easy to follow even for beginner...

Evidence for a Resting State Network Abnormality in Adults Who Stutter

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Amir H. Ghaderi

2018-04-01

Full Text Available Neural network-based investigations of stuttering have begun to provide a possible integrative account for the large number of brain-based anomalies associated with stuttering. Here we used resting-state EEG to investigate functional brain networks in adults who stutter (AWS. Participants were 19 AWS and 52 age-, and gender-matched normally fluent speakers. EEGs were recorded and connectivity matrices were generated by LORETA in the theta (4–8 Hz, alpha (8–12 Hz, beta1 (12–20 Hz, and beta2 (20–30 Hz bands. Small-world propensity (SWP, shortest path, and clustering coefficients were computed for weighted graphs. Minimum spanning tree analysis was also performed and measures were compared by non-parametric permutation test. The results show that small-world topology was evident in the functional networks of all participants. Three graph indices (diameter, clustering coefficient, and shortest path exhibited significant differences between groups in the theta band and one [maximum betweenness centrality (BC] measure was significantly different between groups in the beta2 band. AWS show higher BC than control in right temporal and inferior frontal areas and lower BC in the right primary motor cortex. Abnormal functional networks during rest state suggest an anomaly of DMN activity in AWS. Furthermore, functional segregation/integration deficits in the theta network are evident in AWS. These deficits reinforce the hypothesis that there is a neural basis for abnormal executive function in AWS. Increased beta2 BC in the right speech–motor related areas confirms previous evidence that right audio–speech areas are over-activated in AWS. Decreased beta2 BC in the right primary motor cortex is discussed in relation to abnormal neural mechanisms associated with time perception in AWS.

Resting state functional connectivity of the anterior cingulate cortex in veterans with and without post-traumatic stress disorder

NARCIS (Netherlands)

Kennis, Mitzy; Rademaker, Arthur R.; van Rooij, Sanne J H; Kahn, René S.; Geuze, Elbert

2015-01-01

Post-traumatic stress disorder (PTSD) is an anxiety disorder that is associated with structural and functional alterations in several brain areas, including the anterior cingulate cortex (ACC). Here, we examine resting state functional connectivity of ACC subdivisions in PTSD, using a seed-based

Resting-state functional connectivity differences in premature children

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Eswar Damaraju

2010-06-01

Full Text Available We examine the coherence in the spontaneous brain activity of sleeping children as measured by the blood oxygenation level dependent (BOLD functional magnetic resonance imaging (fMRI signals. The results are described in terms of resting-state networks (RSN and their properties. More specifically, in this study we examine the effect of severe prematurity on the spatial location of the visual, temporal, motor, basal ganglia, and the default mode networks, the temporal response properties of each of these networks, and the functional connectivity between them. Our results suggest that the anatomical locations of the RSNs are well developed by 18 months of age and their spatial locations are not distinguishable between premature and term born infants at 18 months or at 36 months, with the exception of small spatial differences noted in the basal ganglia area and the visual cortex. The two major differences between term and preterm children were present at 36 but not 18 months and include: 1 increased spectral energy in the low frequency range (0.01 – 0.06 Hz for pre-term children in the basal ganglia component, and 2 stronger connectivity between RSNs in term children. We speculate that children born very prematurely are vulnerable to injury resulting in weaker connectivity between resting state networks by 36 months of age. Further work is required to determine whether this could be a clinically useful tool to identify children at risk of developmental delay related to premature birth.

Determination numbers of ionized atoms from emission and absorption lines

International Nuclear Information System (INIS)

Alizadeh Azimi, A.; Shokouhi, N.

2002-01-01

Saha, M., (1920) estimated that salter chromosphere is not only due to radiation from neutral atoms, but from ionized atoms. The failure to observe these stellar lines in the laboratory was attributed to internal temperature and pressure about 10* E + 6 K 10* E-7 atm. In this research we found that emission lines of ionized atoms (like Cs) could be measured in laboratory condition, (about 10* E-3 atm and 2000 K) by using Graphite France Atomic Absorption with injection 124 u g C sel. We calculated the numbers of ionized atoms from Bottzman law. We also measured these numbers from area under the energy-time curve

Atomization of volatile compounds for atomic absorption and atomic fluorescence spectrometry: On the way towards the ideal atomizer

International Nuclear Information System (INIS)

Dedina, Jiri

2007-01-01

This review summarizes and discusses the individual atomizers of volatile compounds. A set of criteria important for analytical praxis is used to rank all the currently existing approaches to the atomization based on on-line atomization for atomic absorption (AAS) and atomic fluorescence spectrometry (AFS) as well as on in-atomizer trapping for AAS. Regarding on-line atomization for AAS, conventional quartz tubes are currently the most commonly used devices. They provide high sensitivity and low baseline noise. Running and investment costs are low. The most serious disadvantage is the poor resistance against atomization interferences and often unsatisfactory linearity of calibration graphs. Miniature diffusion flame (MDF) is extremely resistant to interferences, simple, cheap and user-friendly. Its essential disadvantage is low sensitivity. A novel device, known as a multiatomizer, was designed to overcome disadvantages of previous atomizers. It matches performance of conventional quartz tubes in terms of sensitivity and baseline noise as well as in running and investment costs. The multiatomizer, however, provides much better (i) resistance against atomization interferences and (ii) linearity of calibration graphs. In-atomizer trapping enhances the sensitivity of the determination and eliminates the effect of the generation kinetics and of surges in gas flow on the signal shape. This is beneficial for the accuracy of the determination. It could also be an effective tool for reducing some interferences in the liquid phase. In-situ trapping in graphite furnaces (GF) is presently by far the most popular approach to the in-atomizer trapping. Its resistance against interferences is reasonably good and it can be easily automated. In-situ trapping in GF is a mature method well established in various application fields. These are the reasons to rank in-situ trapping in GF as currently the most convenient approach to hydride atomization for AAS. The recently suggested

Holographic atom imaging from experimental photoelectron angular distribution patterns

International Nuclear Information System (INIS)

Terminello, L.J.; Lapiano-Smith, D.A.; Barton, J.J.; Shirley, D.A.

1993-11-01

One of the most challenging areas of materials research is the imaging of technologically relevant materials with microscopic and atomic-scale resolution. As part of the development of these methods, near-surface atoms in single crystals were imaged using core-level photoelectron holograms. The angle-dependent electron diffraction patterns that constitute an electron hologram were two-dimensionally transformed to create a three dimensional, real-space image of the neighboring scattering atoms. They have made use of a multiple-wavenumber, phased-summing method to improve the atom imaging capabilities of experimental photoelectron holography using the Cu(001) and Pt(111) prototype systems. These studies are performed to evaluate the potential of holographic atom imaging methods as structural probes of unknown materials

Network based statistical analysis detects changes induced by continuous theta burst stimulation on brain activity at rest.

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Chiara eMastropasqua

2014-08-01

Full Text Available We combined continuous theta burst stimulation (cTBS and resting state (RS -fMRI approaches to investigate changes in functional connectivity (FC induced by right dorso-lateral prefrontal cortex (DLPFC cTBS at rest in a group of healthy subjects. Seed based fMRI analysis revealed a specific pattern of correlation between the right prefrontal cortex and several brain regions: based on these results, we defined a 29-node network to assess changes in each network connection before and after, respectively, DLPFC-cTBS and sham sessions. A decrease of correlation between the right prefrontal cortex and right parietal cortex (Brodmann areas 46 and 40 respectively was detected after cTBS, while no significant result was found when analyzing sham-session data. To our knowledge, this is the first study that demonstrates within-subject changes in FC induced by cTBS applied on prefrontal area. The possibility to induce selective changes in a specific region without interfering with functionally correlated area could have several implications for the study of functional properties of the brain, and for the emerging therapeutic strategies based on transcranial stimulation.

Sleeper Cab Climate Control Load Reduction for Long-Haul Truck Rest Period Idling

Energy Technology Data Exchange (ETDEWEB)

Lustbader, J. A.; Kreutzer, C.; Adelman, S.; Yeakel, S.; Zehme, J.

2015-04-29

Annual fuel use for long-haul truck rest period idling is estimated at 667 million gallons in the United States. The U.S. Department of Energy’s National Renewable Energy Laboratory’s CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck climate control systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In order for candidate idle reduction technologies to be implemented at the original equipment manufacturer and fleet level, their effectiveness must be quantified. To address this need, a number of promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads. For this study, load reduction strategies were grouped into the focus areas of solar envelope, occupant environment, and conductive pathways. The technologies selected for a complete-cab package of technologies were “ultra-white” paint, advanced insulation, and advanced curtains. To measure the impact of these technologies, a nationally-averaged solar-weighted reflectivity long-haul truck paint color was determined and applied to the baseline test vehicle. Using the complete-cab package of technologies, electrical energy consumption for long-haul truck daytime rest period air conditioning was reduced by at least 35% for summer weather conditions in Colorado. The National Renewable Energy Laboratory's CoolCalc model was then used to extrapolate the performance of the thermal load reduction technologies nationally for 161 major U.S. cities using typical weather conditions for each location over an entire year.

The Rest-Activity Rhythm and Physical Activity in Early-Onset Dementia

NARCIS (Netherlands)

Hooghiemstra, A.M.; Eggermont, L.H.P.; Scheltens, P.; van der Flier, W.M.; Scherder, E.J.A.

2015-01-01

Background: A substantial part of elderly persons with dementia show rest-activity rhythm disturbances. The rest-activity rhythm is important to study in people with early-onset dementia (EOD) for rest-activity rhythm disturbances are predictive of institutionalization, and caregivers of young

Advances in atomic, molecular, and optical physics

CERN Document Server

Walther, Herbert; Walther, Herbert

2005-01-01

This series, established in 1965, is concerned with recent developments in the general area of atomic, molecular and optical physics. The field is in a state of rapid growth, as new experimental and theoretical techniques are used on many old and new problems. Topics covered include related applied areas, such as atmospheric science, astrophysics, surface physics and laser physics. Articles are written by distinguished experts who are active in their research fields. The articles contain both relevant review material and detailed descriptions of important recent developments. · Reviews timely fields of atomic physics · Articles written by world leaders in those fields · In depth review of the subject with relevant literature · Suitable for researchers in other fields · Only book series of this kind.

Atomic collisions related to atomic laser isotope separation

International Nuclear Information System (INIS)

Shibata, Takemasa

1995-01-01

Atomic collisions are important in various places in atomic vapor laser isotope separation (AVLIS). At a vaporization zone, many atomic collisions due to high density have influence on the atomic beam characteristics such as velocity distribution and metastable states' populations at a separation zone. In the separation zone, a symmetric charge transfer between the produced ions and the neutral atoms may degrade selectivity. We have measured atomic excitation temperatures of atomic beams and symmetric charge transfer cross sections for gadolinium and neodymium. Gadolinium and neodymium are both lanthanides. Nevertheless, results for gadolinium and neodymium are very different. The gadolinium atom has one 5d electron and neodymium atom has no 5d electron. It is considered that the differences are due to existence of 5d electron. (author)

Nuclear energy and the responsibilities of the Atomic Energy Board

International Nuclear Information System (INIS)

De Villiers, J.W.L.

1980-01-01

The paper discusses nuclear energy and the responsibilities of the previous Atomic Energy Board, (now the Atomic Energy Corporation) of South Africa in this respect. The paper starts by giving a brief introduction to the Atomic Energy Board, its organization and its functions. Research is undertaken in various fields such as the exploitation of nuclear fuels, radiobiology, radioisotopes, etc. Certain activities of the Board was also more directly related to Koeberg. The paper covers four of these areas, namely the early studies of the feasibility of introducing nuclear power in South Africa; the services involving the Board's special expertise in certain areas which Escom makes use of; the regulatory function and the preparation for handling and disposal of radioactive waste

Superradiators created atom by atom

Science.gov (United States)

Meschede, Dieter

2018-02-01

High radiation rates are usually associated with macroscopic lasers. Laser radiation is “coherent”—its amplitude and phase are well-defined—but its generation requires energy inputs to overcome loss. Excited atoms spontaneously emit in a random and incoherent fashion, and for N such atoms, the emission rate simply increases as N. However, if these atoms are in close proximity and coherently coupled by a radiation field, this microscopic ensemble acts as a single emitter whose emission rate increases as N2 and becomes “superradiant,” to use Dicke's terminology (1). On page 662 of this issue, Kim et al. (2) show the buildup of coherent light fields through collective emission from atomic radiators injected one by one into a resonator field. There is only one atom ever in the cavity, but the emission is still collective and superradiant. These results suggest another route toward thresholdless lasing.

Effect of rest interval on strength recovery in young and old women.

Science.gov (United States)

Theou, Olga; Gareth, Jones R; Brown, Lee E

2008-11-01

This study compares the effects of rest intervals on isokinetic muscle torque recovery between sets of a knee extensor and flexor exercise protocol in physically active younger and older women. Twenty young (22.4 +/- 1.7 years) and 16 older (70.7 +/- 4.3 years) women performed three sets of eight maximum repetitions of knee extension/flexion at 60 degrees x s(-1). The rest interval between sets was 15, 30, and 60 seconds and was randomly assigned across three testing days. No significant interaction of rest by set by age group was observed. There was a significant decline in mean knee extensor torque when 15- and 30-second rest intervals were used between sets, but not when a 60-second rest interval was applied for both the young and the old women. No significant decline for mean knee flexor torque was observed in the older women when a 30-second rest interval was used, whereas a longer 60-second rest interval was required in younger women. Active younger and older women require similar rest intervals between sets of a knee extensor exercise (60 seconds) for complete recovery. However, older women recovered faster (30 seconds) than younger women (60 seconds) between sets of a knee flexor exercise. The exercise-to-rest ratio for knee extensors was similar for young and old women (1:2). Old women required only a 1:1 exercise-to-rest ratio for knee flexor recovery, whereas younger women required a longer 1:2 exercise-to-rest ratio. The results of the present study are specific to isokinetic testing and training and are more applicable in rehabilitation and research settings. Practitioners should consider age and gender when prescribing rest intervals between sets.

Comparison of Nitrate-augmented resting gated 99mTc-Sestamibi imaging with Low Dose Dobutamine SPECT for the detection of Myocardial Viability

International Nuclear Information System (INIS)

Parameswaran, R.V.; Dash, P.K.; Barooah, B.; Guruprasad, H.P.; Purantharan, N.

2002-01-01

Background: Dobutamine Echocardiography and Radionuclide imaging with Tl-201 and Technetium agents are two of the most established techniques available for the detection of viable myocardium. The purpose of this study was to evaluate the utility of Low dose Dobutamine gated Myocardial SPECT in identifying additional areas of dysfunctional, but viable myocardium when compared to nitrate-augmented rest gated SPECT with SestaMIBI. Materials and Methods: 20 patients (19 males and 1 female, with an age range of 40- 65 yrs and a mean of 52.75yrs) all with history of MI or severe LV dysfunction were included in this study. Patients with LBBB, recent revascularisation, arrhythmias etc were excluded from the study. A routine stress-rest study was initially performed on them with 99mTc-SestaMIBI and both the stress as well as resting studies was gated and the resting study was augmented with 10mg of sublingual nitrate. After the resting study was over, the patient was infused with Low dose Dobutamine(5μg/kg/min), at which time the gated acquisition was started and the infusion was continued till the acquisition got completed. In the perfusion study with SestaMIBI, all infarct segments which have uptake less than 50% as compared to the maximally perfused area was deemed non-viable Results: A 17-segment Myocardial model was used for both perfusion as well as quantification of wall motion and wall thickening. 110 akinetic/dyskinetic segments were taken up for analysis. 93 of these segments were non-viable and improvement in wall motion was seen in 17 segments (15.4%) in the nitrate-augmented SPECT. Dobutamine study showed improvement in totally in 27 segments (24.5%), 10 of which were additional segments which were non-viable in Nitrate SPECT study, apart from the 17 segments which showed improvement in the Nitrate study. In Dobutamine study, there was also improvement in wall thickening in 10 (10.7%) out of 93 segments which had showed less than 50% of MIBI uptake. Conclusion

[Intervention to reduce the impact of light and noise on sleep in an emergency department observation area].

Science.gov (United States)

Villamor Ordozgoiti, Alberto; Priu Parra, Inmaculada; España Salvador, María Carmen; Torres Valdés, Constancia; Bas Ciutad, María Pilar; Ponce Quílez, María Rosa

2017-02-01

To study quality of patient rest before and after an intervention to reduce nighttime light and noise in the emergency department observation area of an urban hospital. Quasi-experimental study in 2 groups before and after the intervention in the observation area of the Hospital Clínic de Barcelona. We administered a questionnaire about the quality of nighttime rest to assess the effect of light and noise on sleep. Light and noise were reduced by means of structural changes to the environment and through the introduction of protocols to modify how care plans were carried out at night. Fifty nurses participated in the pre-intervention study and 371 in the post-intervention study. Seventy-two percent and 91.37% of the patients reported resting well before and after the intervention, respectively (P< .001). Factors like pain, nursing care, or daytime naps do not affect sleep quality. Nighttime rest in emergency department observation areas is affected by ambient light and noise more than by other variables. Reducing light and noise at night can measurably improve patients' rest.

Resting-State Functional Magnetic Resonance Imaging for Language Preoperative Planning

Science.gov (United States)

Branco, Paulo; Seixas, Daniela; Deprez, Sabine; Kovacs, Silvia; Peeters, Ronald; Castro, São L.; Sunaert, Stefan

2016-01-01

Functional magnetic resonance imaging (fMRI) is a well-known non-invasive technique for the study of brain function. One of its most common clinical applications is preoperative language mapping, essential for the preservation of function in neurosurgical patients. Typically, fMRI is used to track task-related activity, but poor task performance and movement artifacts can be critical limitations in clinical settings. Recent advances in resting-state protocols open new possibilities for pre-surgical mapping of language potentially overcoming these limitations. To test the feasibility of using resting-state fMRI instead of conventional active task-based protocols, we compared results from fifteen patients with brain lesions while performing a verb-to-noun generation task and while at rest. Task-activity was measured using a general linear model analysis and independent component analysis (ICA). Resting-state networks were extracted using ICA and further classified in two ways: manually by an expert and by using an automated template matching procedure. The results revealed that the automated classification procedure correctly identified language networks as compared to the expert manual classification. We found a good overlay between task-related activity and resting-state language maps, particularly within the language regions of interest. Furthermore, resting-state language maps were as sensitive as task-related maps, and had higher specificity. Our findings suggest that resting-state protocols may be suitable to map language networks in a quick and clinically efficient way. PMID:26869899

A resting bottom sodium cooled fast reactor

International Nuclear Information System (INIS)

Costes, D.

2012-01-01

This follows ICAPP 2011 paper 11059 'Fast Reactor with a Cold Bottom Vessel', on sodium cooled reactor vessels in thermal gradient, resting on soil. Sodium is frozen on vessel bottom plate, temperature increasing to the top. The vault cover rests on the safety vessel, the core diagrid welded to a toric collector forms a slab, supported by skirts resting on the bottom plate. Intermediate exchangers and pumps, fixed on the cover, plunge on the collector. At the vessel top, a skirt hanging from the cover plunges into sodium, leaving a thin circular slit partially filled by sodium covered by argon, providing leak-tightness and allowing vessel dilatation, as well as a radial relative holding due to sodium inertia. No 'air conditioning' at 400 deg. C is needed as for hanging vessels, and this allows a large economy. The sodium volume below the slab contains isolating refractory elements, stopping a hypothetical corium flow. The small gas volume around the vessel limits any LOCA. The liner cooling system of the concrete safety vessel may contribute to reactor cooling. The cold resting bottom vessel, proposed by the author for many years, could avoid the complete visual inspection required for hanging vessels. However, a double vessel, containing support skirts, would allow introduction of inspecting devices. Stress limiting thermal gradient is obtained by filling secondary sodium in the intermediate space. (authors)

New sources of cold atoms for atomic clocks

International Nuclear Information System (INIS)

Aucouturier, E.

1997-01-01

The purpose of this doctoral work is the realisation of new sources of cold cesium atoms that could be useful for the conception of a compact and high-performance atomic clock. It is based on experiences of atomic physics using light induced atomic manipulation. We present here the experiences of radiative cooling of atoms that have been realised at the Laboratoire de l'Horloge Atomique from 1993 to 1996. Firstly, we applied the techniques of radiative cooling and trapping of atoms in order to create a three-dimensional magneto-optical trap. For this first experience, we developed high quality laser sources, that were used for other experiments. We imagined a new configuration of trapping (two-dimensional magneto-optical trap) that was the basis for a cold atom source. This design gives the atoms a possibility to escape towards one particular direction. Then, we have extracted the atoms from this anisotropic trap in order to create a continuous beam of cold atoms. We have applied three methods of extraction. Firstly, the launching of atoms was performed by reducing the intensity of one of the cooling laser beams in the desired launching direction. Secondly, a frequency detuning between the two laser laser beams produced the launching of atoms by a so-called 'moving molasses'. The third method consisted in applying a static magnetic field that induced the launching of atoms in the direction of this magnetic field. At the same time, another research on cold atoms was initiated at the I.H.A. It consisted in cooling a large volume of atoms from a cell, using an isotropic light. This offers an interesting alternative to the traditional optical molasses. (author)

REST controls self-renewal and tumorigenic competence of human glioblastoma cells.

Directory of Open Access Journals (Sweden)

Luciano Conti

Full Text Available The Repressor Element 1 Silencing Transcription factor (REST/NRSF is a master repressor of neuronal programs in non-neuronal lineages shown to function as a central regulator of developmental programs and stem cell physiology. Aberrant REST function has been associated with a number of pathological conditions. In cancer biology, REST has been shown to play a tumor suppressor activity in epithelial cancers but an oncogenic role in brain childhood malignancies such as neuroblastoma and medulloblastoma. Here we examined REST expression in human glioblastoma multiforme (GBM specimens and its role in GBM cells carrying self-renewal and tumorigenic competence. We found REST to be expressed in GBM specimens, its presence being particularly enriched in tumor cells in the perivascular compartment. Significantly, REST is highly expressed in self-renewing tumorigenic-competent GBM cells and its knock down strongly reduces their self-renewal in vitro and tumor-initiating capacity in vivo and affects levels of miR-124 and its downstream targets. These results indicate that REST contributes to GBM maintenance by affecting its self-renewing and tumorigenic cellular component and that, hence, a better understanding of these circuitries in these cells might lead to new exploitable therapeutic targets.

Atomic physics precise measurements and ultracold matter

CERN Document Server

Inguscio, Massimo

2013-01-01

Atomic Physics provides an expert guide to two spectacular new landscapes in physics: precision measurements, which have been revolutionized by the advent of the optical frequency comb, and atomic physics, which has been revolutionized by laser cooling. These advances are not incremental but transformative: they have generated a consilience between atomic and many-body physics, precipitated an explosion of scientific and technological applications, opened new areas of research, and attracted a brilliant generation of younger scientists. The research is advancing so rapidly, the barrage of applications is so dazzling, that students can be bewildered. For both students and experienced scientists, this book provides an invaluable description of basic principles, experimental methods, and scientific applications.

Thallium-201 myocardial scintigraphy and left ventricular function at rest in patients with rest angina pectoris

International Nuclear Information System (INIS)

Hakki, A.H.; Iskandrian, A.S.; Kane, S.A.; Amenta, A.

1984-01-01

The purpose of this study was to examine the rest thallium-201 perfusion pattern during angina-free periods in 40 patients with rest angina pectoris secondary to coronary artery disease (greater than or equal to 70% diameter narrowing). Seventeen patients had previous Q wave myocardial infarction. The perfusion defects were considered fixed or reversible, depending on the absence or presence of redistribution in the 4-hour delayed images. There were 40 perfusion defects (26 fixed and 14 reversible) in 27 patients whereas 13 patients had normal scans. Reversible perfusion defects were present in 10 patients (25%). Of the 26 fixed perfusion defects, 17 did not have corresponding Q waves. Occluded vessels (63%) had more perfusion defects than vessels with subtotal occlusion (30%) (p less than 0.01). The perfusion defect size was larger in patients with lower ejection fraction than in patients with higher ejection fraction. We conclude: (1) perfusion defects are common in patients with rest angina and are reversible in 25% of patients indicating reduced regional coronary blood flow; (2) the degree of stenosis affects the presence of perfusion defect; (3) fixed defects may be present without corresponding Q waves; and (4) global left ventricular function is related to the size of perfusion defects

Mapping Hydrophobicity on the Protein Molecular Surface at Atom-Level Resolution

Science.gov (United States)

Nicolau Jr., Dan V.; Paszek, Ewa; Fulga, Florin; Nicolau, Dan V.

2014-01-01

A precise representation of the spatial distribution of hydrophobicity, hydrophilicity and charges on the molecular surface of proteins is critical for the understanding of the interaction with small molecules and larger systems. The representation of hydrophobicity is rarely done at atom-level, as this property is generally assigned to residues. A new methodology for the derivation of atomic hydrophobicity from any amino acid-based hydrophobicity scale was used to derive 8 sets of atomic hydrophobicities, one of which was used to generate the molecular surfaces for 35 proteins with convex structures, 5 of which, i.e., lysozyme, ribonuclease, hemoglobin, albumin and IgG, have been analyzed in more detail. Sets of the molecular surfaces of the model proteins have been constructed using spherical probes with increasingly large radii, from 1.4 to 20 Å, followed by the quantification of (i) the surface hydrophobicity; (ii) their respective molecular surface areas, i.e., total, hydrophilic and hydrophobic area; and (iii) their relative densities, i.e., divided by the total molecular area; or specific densities, i.e., divided by property-specific area. Compared with the amino acid-based formalism, the atom-level description reveals molecular surfaces which (i) present an approximately two times more hydrophilic areas; with (ii) less extended, but between 2 to 5 times more intense hydrophilic patches; and (iii) 3 to 20 times more extended hydrophobic areas. The hydrophobic areas are also approximately 2 times more hydrophobicity-intense. This, more pronounced “leopard skin”-like, design of the protein molecular surface has been confirmed by comparing the results for a restricted set of homologous proteins, i.e., hemoglobins diverging by only one residue (Trp37). These results suggest that the representation of hydrophobicity on the protein molecular surfaces at atom-level resolution, coupled with the probing of the molecular surface at different geometric resolutions

Atomic physics research with synchrotron radiation

International Nuclear Information System (INIS)

Crasemann, B.

1981-01-01

Applications of synchrotron radiation to research in high-energy atomic physics are summarized. These lie in the areas of photoelectron spectrometry, photon scattering, x-ray absorption spectroscopy, time-resolved measurements, resonance spectroscopy and threshold excitation, and future, yet undefined studies

Complex network analysis of resting-state fMRI of the brain.

Science.gov (United States)

Anwar, Abdul Rauf; Hashmy, Muhammad Yousaf; Imran, Bilal; Riaz, Muhammad Hussnain; Mehdi, Sabtain Muhammad Muntazir; Muthalib, Makii; Perrey, Stephane; Deuschl, Gunther; Groppa, Sergiu; Muthuraman, Muthuraman

2016-08-01

Due to the fact that the brain activity hardly ever diminishes in healthy individuals, analysis of resting state functionality of the brain seems pertinent. Various resting state networks are active inside the idle brain at any time. Based on various neuro-imaging studies, it is understood that various structurally distant regions of the brain could be functionally connected. Regions of the brain, that are functionally connected, during rest constitutes to the resting state network. In the present study, we employed the complex network measures to estimate the presence of community structures within a network. Such estimate is named as modularity. Instead of using a traditional correlation matrix, we used a coherence matrix taken from the causality measure between different nodes. Our results show that in prolonged resting state the modularity starts to decrease. This decrease was observed in all the resting state networks and on both sides of the brain. Our study highlights the usage of coherence matrix instead of correlation matrix for complex network analysis.

The combination of short rest and energy drink consumption as fatigue countermeasures during a prolonged drive of professional truck drivers.

Science.gov (United States)

Ronen, Adi; Oron-Gilad, Tal; Gershon, Pnina

2014-06-01

One of the major concerns for professional drivers is fatigue. Many studies evaluated specific fatigue countermeasures, in many cases comparing the efficiency of each method separately. The present study evaluated the effectiveness of rest areas combined with consumption of energy drinks on professional truck drivers during a prolonged simulated drive. Fifteen professional truck drivers participated in three experimental sessions: control-drivers were asked to drink 500 ml of a placebo drink prior to the beginning of the drive. Energy drink-drivers were asked to drink 500 ml of an energy drink containing 160 mg of caffeine prior to the beginning of the drive, and an Energy drink+Rest session--where the drivers were asked to drink 500 ml of an energy drink prior to driving, and rest for 10 min at a designated rest area zone 100 min into the drive. For all sessions, driving duration was approximately 150 min and consisted of driving on a monotonous, two-way rural road. In addition to driving performance measures, subjective measures, and heart rate variability were obtained. Results indicated that consumption of an energy drink (in both sessions) facilitated lower lane position deviations and reduced steering wheel deviations during the first 80-100 min of the drive relative to the control sessions. Resting after 100 min of driving, in addition to the energy drink that was consumed before the drive, enabled the drivers to maintain these abilities throughout the remainder of the driving session. Practical applications: Practical applications arising from the results of this research may give indication on the possible added value of combining fatigue counter measures methods during a prolonged drive and the importance of the timing of the use for each method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Atomic absorption spectrometry

International Nuclear Information System (INIS)

Haswell, S.J.

1991-01-01

Atomic absorption spectroscopy is now well established and widely used technique for the determination of trace and major elements in a wide range analyte types. There have been many advances in the atomic spectroscopy over the last decade and for this reason and to meet the demand, it was felt that there was a need for an updated book. Whilst interest in instrumental design has tended to dominate the minds of the spectrocopist, the analyst concerned with obtaining reliable and representative data, in diverse areas of application, has been diligently modifying and developing sample treatment and instrumental introduction techniques. Such methodology is de fundamental part of analysis and form the basis of the fourteen application chapters of this book. The text focuses in the main on AAS; however, the sample handling techniques described are in many cases equally applicable to ICP-OES and ICP-MS analysis. (author). refs.; figs.; tabs

Exclusive channels in bar pp annihilation at rest

International Nuclear Information System (INIS)

Bluem, P.

1992-01-01

Exclusive channels in bar pp annihilation at rest provide a powerful tool for studying the meson spectrum below the bar pp threshold. The mesons can be classified in SU(3) multiplets according to their quantum numbers. The states which do not fit into this classification are candidates for new forms of hadronic matter like glueballs, hybrids, and multi-quark states. Recent results on the search for exotic states in exclusive channels of bar pp annihilation at rest are discussed. No less important is the study of the annihilation mechanism. In particular, high-statistic measurements of bar pp annihilation at rest into two-meson final states are an excellent tool for studying quark dynamics. Examples of two-body reactions are presented. 24 refs., 9 figs., 3 tabs

Memory reactivation during rest supports upcoming learning of related content

Science.gov (United States)

Schlichting, Margaret L.; Preston, Alison R.

2014-01-01

Although a number of studies have highlighted the importance of offline processes for memory, how these mechanisms influence future learning remains unknown. Participants with established memories for a set of initial face–object associations were scanned during passive rest and during encoding of new related and unrelated pairs of objects. Spontaneous reactivation of established memories and enhanced hippocampal–neocortical functional connectivity during rest was related to better subsequent learning, specifically of related content. Moreover, the degree of functional coupling during rest was predictive of neural engagement during the new learning experience itself. These results suggest that through rest-phase reactivation and hippocampal–neocortical interactions, existing memories may come to facilitate encoding during subsequent related episodes. PMID:25331890

Memory reactivation during rest supports upcoming learning of related content.

Science.gov (United States)

Schlichting, Margaret L; Preston, Alison R

2014-11-04

Although a number of studies have highlighted the importance of offline processes for memory, how these mechanisms influence future learning remains unknown. Participants with established memories for a set of initial face-object associations were scanned during passive rest and during encoding of new related and unrelated pairs of objects. Spontaneous reactivation of established memories and enhanced hippocampal-neocortical functional connectivity during rest was related to better subsequent learning, specifically of related content. Moreover, the degree of functional coupling during rest was predictive of neural engagement during the new learning experience itself. These results suggest that through rest-phase reactivation and hippocampal-neocortical interactions, existing memories may come to facilitate encoding during subsequent related episodes.

Atom interferometry with trapped Bose-Einstein condensates: impact of atom-atom interactions

International Nuclear Information System (INIS)

Grond, Julian; Hohenester, Ulrich; Mazets, Igor; Schmiedmayer, Joerg

2010-01-01

Interferometry with ultracold atoms promises the possibility of ultraprecise and ultrasensitive measurements in many fields of physics, and is the basis of our most precise atomic clocks. Key to a high sensitivity is the possibility to achieve long measurement times and precise readout. Ultracold atoms can be precisely manipulated at the quantum level and can be held for very long times in traps; they would therefore be an ideal setting for interferometry. In this paper, we discuss how the nonlinearities from atom-atom interactions, on the one hand, allow us to efficiently produce squeezed states for enhanced readout and, on the other hand, result in phase diffusion that limits the phase accumulation time. We find that low-dimensional geometries are favorable, with two-dimensional (2D) settings giving the smallest contribution of phase diffusion caused by atom-atom interactions. Even for time sequences generated by optimal control, the achievable minimal detectable interaction energy ΔE min is of the order of 10 -4 μ, where μ is the chemical potential of the Bose-Einstein condensate (BEC) in the trap. From these we have to conclude that for more precise measurements with atom interferometers, more sophisticated strategies, or turning off the interaction-induced dephasing during the phase accumulation stage, will be necessary.

Annihilation of antiproton on deuteron at rest

International Nuclear Information System (INIS)

Grach, I.; Shmatikov, M.

1982-01-01

The system of Faddeev equations for amplitudes of anti pD iteraction at rest accounting for higher partial anti NN waves is derived. From its solution the total and elastic anti pD cross sections are calculated. Predictions for the missing-mass spectrum in the anti pD annihilation are made. The P-wave anti NN states give small contribution to the anti pD cross section at rest, the theoretical value of the latter being less than the experimental cross section extrapolated to the threshold. Let us emphasize that the total anti pD cross section depending weakly on the radii of anti NN interactions is sensitive to the values of the anti NN scattering lengths. Experimental data for anti pD cross sections at rest can be obtained only by extrapolation procedure. Henceforth it is very important to investigate the anti pD interactions at low but non-zero momenta where the direct comparison to the experiment is possible [ru

Atom-atom collision cascades localization

International Nuclear Information System (INIS)

Kirsanov, V.V.

1980-01-01

The presence of an impurity and thermal vibration influence on the atom-atom collision cascade development is analysed by the computer simulation method (the modificated dynamic model). It is discovered that the relatively low energetic cascades are localized with the temperature increase of an irradiated crystal. On the basis of the given effect the mechanism of splitting of the high energetic cascades into subcascades is proposed. It accounts for two factors: the primary knocked atom energy and the irradiated crystal temperature. Introduction of an impurity also localizes the cascades independently from the impurity atom mass. The cascades localization leads to intensification of the process of annealing in the cascades and reduction of the post-cascade vacancy cluster sizes. (author)

Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI

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Yu-Chen Chen

2018-03-01

Full Text Available Purpose: Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI approach.Methods: Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF and regional homogeneity (ReHo of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis.Results: Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG, parahippocampal gyrus (PHG, precuneus and inferior parietal lobule (IPL as well as increased neural activity in the middle frontal gyrus (MFG, cuneus and postcentral gyrus (PoCG. A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B scores, indicative of impaired cognitive function involving the frontal lobe.Conclusions: Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI.

Science.gov (United States)

Chen, Yu-Chen; Chen, Huiyou; Jiang, Liang; Bo, Fan; Xu, Jin-Jing; Mao, Cun-Nan; Salvi, Richard; Yin, Xindao; Lu, Guangming; Gu, Jian-Ping

2018-01-01

Purpose : Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI) approach. Methods : Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis. Results : Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG), parahippocampal gyrus (PHG), precuneus and inferior parietal lobule (IPL) as well as increased neural activity in the middle frontal gyrus (MFG), cuneus and postcentral gyrus (PoCG). A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B) scores, indicative of impaired cognitive function involving the frontal lobe. Conclusions : Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

Code ATOM for calculation of atomic characteristics

International Nuclear Information System (INIS)

Vainshtein, L.A.

1990-01-01

In applying atomic physics to problems of plasma diagnostics, it is necessary to determine some atomic characteristics, including energies and transition probabilities, for very many atoms and ions. Development of general codes for calculation of many types of atomic characteristics has been based on general but comparatively simple approximate methods. The program ATOM represents an attempt at effective use of such a general code. This report gives a brief description of the methods used, and the possibilities of and limitations to the code are discussed. Characteristics of the following processes can be calculated by ATOM: radiative transitions between discrete levels, radiative ionization and recombination, collisional excitation and ionization by electron impact, collisional excitation and ionization by point heavy particle (Born approximation only), dielectronic recombination, and autoionization. ATOM explores Born (for z=1) or Coulomb-Born (for z>1) approximations. In both cases exchange and normalization can be included. (N.K.)

Rest requirements and rest management of personnel in shift work

Energy Technology Data Exchange (ETDEWEB)

Hammell, B.D. [PDG Environmental, Melbourne, FL (United States); Scheuerle, A. [Univ. of Texas, Houston, TX (United States)

1995-12-31

A difficulty-weighted shift assignment scheme is proposed for use in prolonged and strenuous field operations such as emergency response, site testing, and short term hazardous waste remediation projects. The purpose of the work rotation plan is to increase productivity, safety, and moral of workers. Job weighting is accomplished by assigning adjustments to the mental and physical intensity of the task, the protective equipment worn, and the climatic conditions. The plan is based on medical studies of sleep deprivation, the effects of rest adjustments, and programs to reduce sleep deprivation and normalize shift schedules.

Different Resting-State Functional Connectivity Alterations in Smokers and Nonsmokers with Internet Gaming Addiction

Directory of Open Access Journals (Sweden)

Xue Chen

2014-01-01

Full Text Available This study investigated changes in resting-state functional connectivity (rsFC of posterior cingulate cortex (PCC in smokers and nonsmokers with Internet gaming addiction (IGA. Twenty-nine smokers with IGA, 22 nonsmokers with IGA, and 30 healthy controls (HC group underwent a resting-state fMRI scan. PCC connectivity was determined in all subjects by investigating synchronized low-frequency fMRI signal fluctuations using a temporal correlation method. Compared with the nonsmokers with IGA, the smokers with IGA exhibited decreased rsFC with PCC in the right rectus gyrus. Left middle frontal gyrus exhibited increased rsFC. The PCC connectivity with the right rectus gyrus was found to be negatively correlated with the CIAS scores in the smokers with IGA before correction. Our results suggested that smokers with IGA had functional changes in brain areas related to motivation and executive function compared with the nonsmokers with IGA.

Mechanisms for decreased exercise capacity after bed rest in normal middle-aged men

International Nuclear Information System (INIS)

Hung, J.; Goldwater, D.; Convertino, V.A.; McKillop, J.H.; Goris, M.L.; DeBusk, R.F.

1983-01-01

The mechanisms responsible for the decrease in exercise capacity after bed rest were assessed in 12 apparently healthy men aged 50 +/- 4 years who underwent equilibrium gated blood pool scintigraphy during supine and upright multistage bicycle ergometry before and after 10 days of bed rest. After bed rest, echocardiographically measured supine resting left ventricular end-diastolic volume decreased by 16% (p less than 0.05). Peak oxygen uptake during supine effort after bed rest was diminished by 6% (p . not significant [NS]), whereas peak oxygen uptake during upright effort declined by 15% (p less than 0.05). After bed rest, increases in heart rate were also greater during exercise in the upright than in the supine position (p less than 0.05). Values of left ventricular ejection fraction increased normally during both supine and upright effort after bed rest and were higher than corresponding values before bed rest (p less than 0.05). After bed rest, increased left ventricular ejection fraction and heart rate largely compensated for the reduced cardiac volume during supine effort, but these mechanisms were insufficient to maintain oxygen transport capacity at levels during upright effort before bed rest. These results indicate that orthostatically induced cardiac underfilling, not physical deconditioning or left ventricular dysfunction, is the major cause of reduced effort tolerance after 10 days of bed rest in normal middle-aged men

Modifications of resting state networks in spinocerebellar ataxia type 2.

Science.gov (United States)

Cocozza, Sirio; Saccà, Francesco; Cervo, Amedeo; Marsili, Angela; Russo, Cinzia Valeria; Giorgio, Sara Maria Delle Acque; De Michele, Giuseppe; Filla, Alessandro; Brunetti, Arturo; Quarantelli, Mario

2015-09-01

We aimed to investigate the integrity of the Resting State Networks in spinocerebellar ataxia type 2 (SCA2) and the correlations between the modification of these networks and clinical variables. Resting-state functional magnetic resonance imaging (RS-fMRI) data from 19 SCA2 patients and 29 healthy controls were analyzed using an independent component analysis and dual regression, controlling at voxel level for the effect of atrophy by co-varying for gray matter volume. Correlations between the resting state networks alterations and disease duration, age at onset, number of triplets, and clinical score were assessed by Spearman's coefficient, for each cluster which was significantly different in SCA2 patients compared with healthy controls. In SCA2 patients, disruption of the cerebellar components of all major resting state networks was present, with supratentorial involvement only for the default mode network. When controlling at voxel level for gray matter volume, the reduction in functional connectivity in supratentorial regions of the default mode network, and in cerebellar regions within the default mode, executive and right fronto-parietal networks, was still significant. No correlations with clinical variables were found for any of the investigated resting state networks. The SCA2 patients show significant alterations of the resting state networks, only partly explained by the atrophy. The default mode network is the only resting state network that shows also supratentorial changes, which appear unrelated to the cortical gray matter volume. Further studies are needed to assess the clinical significance of these changes. © 2015 International Parkinson and Movement Disorder Society.

Atomic, molecular and optical physics

International Nuclear Information System (INIS)

1990-01-01

This is related to the actual situation and perspectives of atomic, molecular and optical physics in Brazil. It gives a general overview of the most important research groups in the above mentioned areas. It discusses as well, the future trends of Brazilian universities and the financing of these groups. (A.C.A.S.)

The way that Ibaraki Prefecture has tackled atomic energy

International Nuclear Information System (INIS)

Nakata, Hirokatsu; Hirai, Yasuo; Tsuji, Tadashi.

1996-01-01

First, the development of the district centering around Tokai Village is mentioned, where at present Japan Atomic Energy Research Institute, Power Reactor and Nuclear Fuel Development Corporation, Japan Atomic Power Co. and others are located. Ibaraki Prefecture investigated the effects that atomic energy facilities exerted economically and socially to the district. As to the social environment investigation related to atomic energy facilities, its purpose, the objects of investigation, the contents and the method of investigation are reported. As to the progress of the development and utilization of atomic energy in Ibaraki Prefecture, 23 establishments are located in the district. Also there are 16 power reactors and research reactors, one fuel reprocessing plant, 4 nuclear fuel fabrication facilities, 86 nuclear fuel using facilities and 28 radioisotope using facilities. Their situations are reported. As to the atomic energy administration of Ibaraki Prefecture, the safety administration and the countermeasures for surrounding areas are explained. The effects exerted to the society and the economy of the district are reported. The results of the investigation of the conscience concerning atomic energy of residents are shown about energy and atomic energy, atomic energy administration, and the relation of atomic energy facilities with the district. (K.I.)

HORMONAL RESPONSE TO DIFFERENT REST INTERVALS DURING RESISTANCE TRAINING WITH LIGHT LOADS

Directory of Open Access Journals (Sweden)

Payam Mohamad-Panahi

2014-02-01

Full Text Available Purpose: The purpose of the present study was to determine the appropriate rest time between sets during weight training with light load. Material: Seventeen cadet wrestlers (age =16.7В±0.6 yrs.; height =169.2В±8.2 cm; and weight =51.4В±7.9 kg were recruited from wrestling clubs in the Iranian province of Kurdistan and served as subjects in this study. This study was conducted over seven sessions with 48 hours recovery between sessions. In the first session, the characteristic features of subjects were recorded and the one repetition maximum in the bench press test was determined for each subject. On 6 separate occasions, subjects performed a 4 set of bench press at 60% 1RM with a 90 and 240 seconds rest interval until volitional fatigue. The numbers of repetition performed by the subjects, and also, cortisol and testosterone levels and 1RM were recorded. The results showed that there was a significant difference in the sustainability of repetitions during 4 sets bench press with 60 % load between 90 and 240 seconds rest intervals (rest interval effect (p<0.05 as well as with 90% load. Results: Additionally, there was a significant difference in the sustainability of repetitions during 4 sets bench press in 90 and 240 seconds rest intervals, both, between light and heavy loads (load effect. Plasma cortisol concentrations significantly increased after all bench press trials. Also, the rest interval effect was statistically significant in both 60 % and 90% load trials. But, the load effect was only statistically significant in 90 seconds rest interval trial (p<0.05. In contrast, plasma testosterone concentrations significantly increased after 4 sets bench press only in 90 seconds rest interval with heavy load and 240 seconds rest interval with light load (p<0.05. Accordingly, testosterone to cortisol (T:C ratio were significantly decreased after 4 sets bench press in 90 seconds rest interval with light load and 240 seconds rest interval with

HORMONAL RESPONSE TO DIFFERENT REST INTERVALS DURING RESISTANCE TRAINING WITH LIGHT LOADS

Directory of Open Access Journals (Sweden)

Payam Mohamad-Panahi

2014-02-01

Full Text Available Purpose: The purpose of the present study was to determine the appropriate rest time between sets during weight training with light load. Material: Seventeen cadet wrestlers (age =16.7±0.6 yrs.; height =169.2±8.2 cm; and weight =51.4±7.9 kg were recruited from wrestling clubs in the Iranian province of Kurdistan and served as subjects in this study. This study was conducted over seven sessions with 48 hours recovery between sessions. In the first session, the characteristic features of subjects were recorded and the one repetition maximum in the bench press test was determined for each subject. On 6 separate occasions, subjects performed a 4 set of bench press at 60% 1RM with a 90 and 240 seconds rest interval until volitional fatigue. The numbers of repetition performed by the subjects, and also, cortisol and testosterone levels and 1RM were recorded. The results showed that there was a significant difference in the sustainability of repetitions during 4 sets bench press with 60 % load between 90 and 240 seconds rest intervals (rest interval effect (p<0.05 as well as with 90% load. Results: Additionally, there was a significant difference in the sustainability of repetitions during 4 sets bench press in 90 and 240 seconds rest intervals, both, between light and heavy loads (load effect. Plasma cortisol concentrations significantly increased after all bench press trials. Also, the rest interval effect was statistically significant in both 60 % and 90% load trials. But, the load effect was only statistically significant in 90 seconds rest interval trial (p<0.05. In contrast, plasma testosterone concentrations significantly increased after 4 sets bench press only in 90 seconds rest interval with heavy load and 240 seconds rest interval with light load (p<0.05. Accordingly, testosterone to cortisol (T:C ratio were significantly decreased after 4 sets bench press in 90 seconds rest interval with light load and 240 seconds rest interval with heavy

Resting state connectivity of the medial prefrontal cortex covaries with individual differences in high-frequency heart rate variability.

Science.gov (United States)

Jennings, J Richard; Sheu, Lei K; Kuan, Dora C-H; Manuck, Stephen B; Gianaros, Peter J

2016-04-01

Resting high-frequency heart rate variability (HF-HRV) relates to cardiac vagal control and predicts individual differences in health and longevity, but its functional neural correlates are not well defined. The medial prefrontal cortex (mPFC) encompasses visceral control regions that are components of intrinsic networks of the brain, particularly the default mode network (DMN) and the salience network (SN). Might individual differences in resting HF-HRV covary with resting state neural activity in the DMN and SN, particularly within the mPFC? This question was addressed using fMRI data from an eyes-open, 5-min rest period during which echoplanar brain imaging yielded BOLD time series. Independent component analysis yielded functional connectivity estimates defining the DMN and SN. HF-HRV was measured in a rest period outside of the scanner. Midlife (52% female) adults were assessed in two studies (Study 1, N = 107; Study 2, N = 112). Neither overall DMN nor SN connectivity strength was related to HF-HRV. However, HF-HRV related to connectivity of one region within mPFC shared by the DMN and SN, namely, the perigenual anterior cingulate cortex, an area with connectivity to other regions involved in autonomic control. In sum, HF-HRV does not seem directly related to global resting state activity of intrinsic brain networks, but rather to more localized connectivity. A mPFC region was of particular interest as connectivity related to HF-HRV was shared by the DMN and SN. These findings may indicate a functional basis for the coordination of autonomic cardiac control with engagement and disengagement from the environment. © 2015 Society for Psychophysiological Research.

Advances in atomic, molecular, and optical physics

CERN Document Server

Walther, Herbert; Walther, Herbert

1999-01-01

This series, established in 1965, is concerned with recent developments in the general area of atomic, molecular, and optical physics. The field is in a state of rapid growth, as new experimental and theoretical techniques are used on many old and new problems. Topics covered also include related applied areas, such as atmospheric science, astrophysics, surface physics, and laser physics.

Hours of work and rest in the rail industry.

Science.gov (United States)

Anderson, C; Grunstein, R R; Rajaratnam, S M W

2013-06-01

Currently, the National Transport Commission is considering four options to form the regulatory framework for rail safety within Australia with respect to fatigue. While the National Transport Commission currently recommends no limitations around hours of work or rest, we provide evidence which suggests regulatory frameworks should incorporate a traditional hours of service regulation over more flexible policies. Our review highlights: Shift durations >12 h are associated with a doubling of risk for accident and injury. Fatigue builds cumulatively with each successive shift where rest in between is inadequate (hours of work and rest, including maximum shift duration and successive number of shifts. Appropriately, validated biomathematical models and technologies may be used as a part of a fatigue management system, to augment the protection afforded by limits on hours of work and rest. A comprehensive sleep disorder screening and management programme should form an essential component of any regulatory framework. © 2013 The Authors; Internal Medicine Journal © 2013 Royal Australasian College of Physicians.

Mapping the brain correlates of borderline personality disorder: A functional neuroimaging meta-analysis of resting state studies.

Science.gov (United States)

Visintin, Eleonora; De Panfilis, Chiara; Amore, Mario; Balestrieri, Matteo; Wolf, Robert Christian; Sambataro, Fabio

2016-11-01

Altered intrinsic function of the brain has been implicated in Borderline Personality Disorder (BPD). Nonetheless, imaging studies have yielded inconsistent alterations of brain function. To investigate the neural activity at rest in BPD, we conducted a set of meta-analyses of brain imaging studies performed at rest. A total of seven functional imaging studies (152 patients with BPD and 147 control subjects) were combined using whole-brain Signed Differential Mapping meta-analyses. Furthermore, two conjunction meta-analyses of neural activity at rest were also performed: with neural activity changes during emotional processing, and with structural differences, respectively. We found altered neural activity in the regions of the default mode network (DMN) in BPD. Within the regions of the midline core DMN, patients with BPD showed greater activity in the anterior as well as in the posterior midline hubs relative to controls. Conversely, in the regions of the dorsal DMN they showed reduced activity compared to controls in the right lateral temporal complex and bilaterally in the orbitofrontal cortex. Increased activity in the precuneus was observed both at rest and during emotional processing. Reduced neural activity at rest in lateral temporal complex was associated with smaller volume of this area. Heterogeneity across imaging studies. Altered activity in the regions of the midline core as well as of the dorsal subsystem of the DMN may reflect difficulties with interpersonal and affective regulation in BPD. These findings suggest that changes in spontaneous neural activity could underlie core symptoms in BPD. Copyright © 2016 Elsevier B.V. All rights reserved.

Branched-chain amino acid supplementation during bed rest: effect on recovery

Science.gov (United States)

Stein, T. P.; Donaldson, M. R.; Leskiw, M. J.; Schluter, M. D.; Baggett, D. W.; Boden, G.

2003-01-01

Bed rest is associated with a loss of protein from the weight-bearing muscle. The objectives of this study are to determine whether increasing dietary branched-chain amino acids (BCAAs) during bed rest improves the anabolic response after bed rest. The study consisted of a 1-day ambulatory period, 14 days of bed rest, and a 4-day recovery period. During bed rest, dietary intake was supplemented with either 30 mmol/day each of glycine, serine, and alanine (group 1) or with 30 mmol/day each of the three BCAAs (group 2). Whole body protein synthesis was determined with U-(15)N-labeled amino acids, muscle, and selected plasma protein synthesis with l-[(2)H(5)]phenylalanine. Total glucose production and gluconeogenesis from alanine were determined with l-[U-(13)C(3)]alanine and [6,6-(2)H(2)]glucose. During bed rest, nitrogen (N) retention was greater with BCAA feeding (56 +/- 6 vs. 26 +/- 12 mg N. kg(-1). day(-1), P < 0.05). There was no effect of BCAA supplementation on either whole body, muscle, or plasma protein synthesis or the rate of 3-MeH excretion. Muscle tissue free amino acid concentrations were increased during bed rest with BCAA (0.214 +/- 0.066 vs. 0.088 +/- 0.12 nmol/mg protein, P < 0.05). Total glucose production and gluconeogenesis from alanine were unchanged with bed rest but were significantly reduced (P < 0.05) with the BCAA group in the recovery phase. In conclusion, the improved N retention during bed rest is due, at least in part, to accretion of amino acids in the tissue free amino acid pools. The amount accreted is not enough to impact protein kinetics in the recovery phase but does improve N retention by providing additional essential amino acids in the early recovery phase.

Atomic physics

International Nuclear Information System (INIS)

Armbruster, P.; Beyer, H.; Bosch, F.; Dohmann, H.D.; Kozhuharov, C.; Liesen, D.; Mann, R.; Mokler, P.H.

1984-01-01

The heavy ion accelerator UNILAC is well suited to experiments in the field of atomic physics because, with the aid of high-energy heavy ions atoms can be produced in exotic states - that is, heavy atoms with only a few electrons. Also, in close collisions of heavy ions (atomic number Z 1 ) and heavy target atoms (Z 2 ) short-lived quasi-atomic 'superheavy' systems will be formed - huge 'atoms', where the inner electrons are bound in the field of the combined charge Z 1 + Z 2 , which exceeds by far the charge of the known elements (Z <= 109). Those exotic or transient superheavy atoms delivered from the heavy ion accelerator make it possible to study for the first time in a terrestrial laboratory exotic, but fundamental, processes, which occur only inside stars. Some of the basic research carried out with the UNILAC is discussed. This includes investigation of highly charged heavy atoms with the beam-foil method, the spectroscopy of highly charged slow-recoil ions, atomic collision studies with highly ionised, decelerated ions and investigations of super-heavy quasi-atoms. (U.K.)

Atomic defects and diffusion in metals

International Nuclear Information System (INIS)

Siegel, R.W.

1981-11-01

The tracer self-diffusion data for fcc and refractory bcc metals are briefly reviewed with respect to (i) the available monovacancy formation and migration properties and (ii) the high-temperature diffusion enhancement above that expected for mass transport via atomic exchange with monovacancies. While the atomic-defect mechanism for low-temperature self-diffusion can be reliably attributed to monovacancies, the mechanisms responsible for high-temperature mass transport are not so easily defined at this time; both divacancies and interstitials must be seriously considered. Possibilities for improving our understanding in this area are discussed. 68 references, 7 figures

Atomic layer deposition of nanostructured materials

CERN Document Server

Pinna, Nicola

2012-01-01

Atomic layer deposition, formerly called atomic layer epitaxy, was developed in the 1970s to meet the needs of producing high-quality, large-area fl at displays with perfect structure and process controllability. Nowadays, creating nanomaterials and producing nanostructures with structural perfection is an important goal for many applications in nanotechnology. As ALD is one of the important techniques which offers good control over the surface structures created, it is more and more in the focus of scientists. The book is structured in such a way to fi t both the need of the expert reader (du

Electron induced atomic inner-shell ionization

International Nuclear Information System (INIS)

Quarles, C.A.

1974-01-01

The current status of cross section measurements for atomic inner-shell ionization by electron bombardment is reviewed. Inner shell ionization studies using electrons as projectiles compliment the similar studies being done with heavy particles, and in addition can provide tests of the theory in those cases when relativistic effects and exchange effects are expected to be important. Both total cross sections and recently measured differential cross sections will be discussed and compared with existing theories where possible. Prospects for further experimental and theoretical work in this area of atomic physics using small electron accelerators will also be discussed

Scaling HEP to Web size with RESTful protocols: The frontier example

International Nuclear Information System (INIS)

Dykstra, Dave

2011-01-01

The World-Wide-Web has scaled to an enormous size. The largest single contributor to its scalability is the HTTP protocol, particularly when used in conformity to REST (REpresentational State Transfer) principles. High Energy Physics (HEP) computing also has to scale to an enormous size, so it makes sense to base much of it on RESTful protocols. Frontier, which reads databases with an HTTP-based RESTful protocol, has successfully scaled to deliver production detector conditions data from both the CMS and ATLAS LHC detectors to hundreds of thousands of computer cores worldwide. Frontier is also able to re-use a large amount of standard software that runs the Web: on the clients, caches, and servers. I discuss the specific ways in which HTTP and REST enable high scalability for Frontier. I also briefly discuss another protocol used in HEP computing that is HTTP-based and RESTful, and another protocol that could benefit from it. My goal is to encourage HEP protocol designers to consider HTTP and REST whenever the same information is needed in many places.

Profiling of REST-dependent microRNAs reveals dynamic modes of expression

Directory of Open Access Journals (Sweden)

Zhengliang eGao

2012-05-01

Full Text Available Multipotent neural stem cells (NSCs possess the ability to self-renew and differentiate into both neurons and glia. However, the detailed mechanisms underlying NSC fate decisions are not well understood. Recent work suggest that the interaction between cell-type specific transcription factors and microRNAs (miRNAs is important as resident neural stem/progenitor cells give rise to functionally mature neurons. Recently, we demonstrated that the transcriptional repressor REST (RE1-silencing transcription factor is essential to prevent precocious neuronal differentiation and maintain NSC self-renewal in the adult hippocampus. Here we show that REST is required for orchestrating the expression of distinct subsets of miRNAs in primary mouse NSC cultures, a physiologically relevant cell type. Using miRNA array profiling, we identified known REST-regulated miRNA genes, as well as previously uncharacterized REST-dependent miRNAs. Interestingly, REST-regulated miRNAs undergo dynamic expression changes under differentiation conditions over time, but not under proliferation conditions. These results suggest that REST functions in a context-dependent manner through its target miRNAs for mediating neuronal production.

Quantum state preparation using multi-level-atom optics

International Nuclear Information System (INIS)

Busch, Th; Deasy, K; Chormaic, S Nic

2007-01-01

One of the most important characteristics for controlling processes on the quantum scale is the fidelity or robustness of the techniques being used. In the case of single atoms localized in micro-traps, it was recently shown that the use of time-dependent tunnelling interactions in a multi-trap setup can be viewed as analogous to the area of multi-level optics. The atom's centre-of-mass can then be controlled with a high fidelity, using a STIRAP-type process. Here, we review previous work that led to the development of multi-level atom optics and present two examples of our most recent work on quantum state preparation

Strength and hypertrophy responses to constant and decreasing rest intervals in trained men using creatine supplementation.

Science.gov (United States)

Souza-Junior, Tácito P; Willardson, Jeffrey M; Bloomer, Richard; Leite, Richard D; Fleck, Steven J; Oliveira, Paulo R; Simão, Roberto

2011-10-27

The purpose of the current study was to compare strength and hypertrophy responses to resistance training programs that instituted constant rest intervals (CI) and decreasing rest intervals (DI) between sets over the course of eight weeks by trained men who supplemented with creatine monohydrate (CR). Twenty-two recreationally trained men were randomly assigned to a CI group (n = 11; 22.3 ± 1 years; 77.7 ± 5.4 kg; 180 ± 2.2 cm) or a DI group (n = 11; 22 ± 2.5 years; 75.8 ± 4.9 kg; 178.8 ± 3.4 cm). Subjects in both groups supplemented with CR; the only difference between groups was the rest interval instituted between sets; the CI group used 2 minutes rest intervals between sets and exercises for the entire 8-weeks of training, while the DI group started with a 2 minute rest interval the first two weeks; after which the rest interval between sets was decreased 15 seconds per week (i.e. 2 minutes decreasing to 30 seconds between sets). Pre- and post-intervention maximal strength for the free weight back squat and bench press exercises and isokinetic peak torque were assessed for the knee extensors and flexors. Additionally, muscle cross-sectional area (CSA) of the right thigh and upper arm was measured using magnetic resonance imaging. Both groups demonstrated significant increases in back squat and bench press maximal strength, knee extensor and flexor isokinetic peak torque, and upper arm and right thigh CSA from pre- to post-training (p ≤ 0.0001); however, there were no significant differences between groups for any of these variables. The total volume for the bench press and back squat were significantly greater for CI group versus the DI group. We report that the combination of CR supplementation and resistance training can increase muscular strength, isokinetic peak torque, and muscle CSA, irrespective of the rest interval length between sets. Because the volume of training was greater for the CI group versus the DI group, yet strength gains were

Strength and hypertrophy responses to constant and decreasing rest intervals in trained men using creatine supplementation

Directory of Open Access Journals (Sweden)

Fleck Steven J

2011-10-01

Full Text Available Abstract Background The purpose of the current study was to compare strength and hypertrophy responses to resistance training programs that instituted constant rest intervals (CI and decreasing rest intervals (DI between sets over the course of eight weeks by trained men who supplemented with creatine monohydrate (CR. Methods Twenty-two recreationally trained men were randomly assigned to a CI group (n = 11; 22.3 ± 1 years; 77.7 ± 5.4 kg; 180 ± 2.2 cm or a DI group (n = 11; 22 ± 2.5 years; 75.8 ± 4.9 kg; 178.8 ± 3.4 cm. Subjects in both groups supplemented with CR; the only difference between groups was the rest interval instituted between sets; the CI group used 2 minutes rest intervals between sets and exercises for the entire 8-weeks of training, while the DI group started with a 2 minute rest interval the first two weeks; after which the rest interval between sets was decreased 15 seconds per week (i.e. 2 minutes decreasing to 30 seconds between sets. Pre- and post-intervention maximal strength for the free weight back squat and bench press exercises and isokinetic peak torque were assessed for the knee extensors and flexors. Additionally, muscle cross-sectional area (CSA of the right thigh and upper arm was measured using magnetic resonance imaging. Results Both groups demonstrated significant increases in back squat and bench press maximal strength, knee extensor and flexor isokinetic peak torque, and upper arm and right thigh CSA from pre- to post-training (p ≤ 0.0001; however, there were no significant differences between groups for any of these variables. The total volume for the bench press and back squat were significantly greater for CI group versus the DI group. Conclusions We report that the combination of CR supplementation and resistance training can increase muscular strength, isokinetic peak torque, and muscle CSA, irrespective of the rest interval length between sets. Because the volume of training was greater for the

Tremor pattern differentiates drug-induced resting tremor from Parkinson disease.

Science.gov (United States)

Nisticò, R; Fratto, A; Vescio, B; Arabia, G; Sciacca, G; Morelli, M; Labate, A; Salsone, M; Novellino, F; Nicoletti, A; Petralia, A; Gambardella, A; Zappia, M; Quattrone, A

2016-04-01

DAT-SPECT, is a well-established procedure for distinguishing drug-induced parkinsonism from Parkinson's disease (PD). We investigated the usefulness of blink reflex recovery cycle (BRrc) and of electromyographic parameters of resting tremor for the differentiation of patients with drug-induced parkinsonism with resting tremor (rDIP) from those with resting tremor due to PD. This was a cross-sectional study. In 16 patients with rDIP and 18 patients with PD we analysed electrophysiological parameters (amplitude, duration, burst and pattern) of resting tremor. BRrc at interstimulus intervals (ISI) of 100, 150, 200, 300, 400, 500 and 750 msec was also analysed in patients with rDIP, patients with PD and healthy controls. All patients and controls underwent DAT-SPECT. Rest tremor amplitude was higher in PD patients than in rDIP patients (p tremor showed a synchronous pattern in all patients with rDIP, whereas it had an alternating pattern in all PD patients (p tremor can be considered a useful investigation for differentiating rDIP from PD. Copyright © 2016. Published by Elsevier Ltd.

REST in practice Hypermedia and systems architecture

CERN Document Server

Webber, Jim; Robinson, Ian

2010-01-01

Why don't typical enterprise projects go as smoothly as projects you develop for the Web? Does the REST architectural style really present a viable alternative for building distributed systems and enterprise-class applications? In this insightful book, three SOA experts provide a down-to-earth explanation of REST and demonstrate how you can develop simple and elegant distributed hypermedia systems by applying the Web's guiding principles to common enterprise computing problems. You'll learn techniques for implementing specific Web technologies and patterns to solve the needs of a typical com

High power atomic iodine photodissociation lasers

International Nuclear Information System (INIS)

Palmer, R.E.; Padrick, T.D.; Jones, E.D.

1976-01-01

The atomic iodine photodissociation laser has developed into a system capable of producing nanosecond or shorter pulses of near infrared radiation with energies well in excess of a hundred J. Discussed are the operating characteristics, advantages, and potential problem areas associated with this laser

Experimental evaluation of the influence of various rests on task performance

International Nuclear Information System (INIS)

Nagasaka, Akihiko; Hirose, Ayako

2000-01-01

This report deals with the result of the experiment that 8 subjects had executed adding task and search task. They executed each task in 80 minutes under 5 conditions: (1) with no rest, and with 4 kinds of 20 minutes rests, in which they (2) opened eyes, (3) closed eyes, (4) closed eyes with listening classic music and (5) closed eyes with feet massage, in the middle of the task. The results of analysis of variance with the task performance in the latter half, there were significant differences between each condition with every subject in adding task, and with 6 subjects in search task. However, the orders of the task performance with each condition were not the same by each subject. It was suggested that transition of the arousal levels under the rest was related to the effects of the rest rather than the subjects' taste in rests. In the rest, the percentage of α wave of electroencephalogram and the coefficient of variation of R-R interval (time interval of heart beats) were increased than in executing task. The mean Kendall's rank correlation of coefficient with the order of increase rate of α/β wave and the task performance in the latter half was slightly negative in adding task, but was about 0.4 in search task. From these results, about six requirements for 'an effective rest' were able to be mentioned, for example, 'the devices that raises the arousal levels is carried out just before a rest end'. (author)

Experimental evaluation of the influence of various rests on task performance

Energy Technology Data Exchange (ETDEWEB)

Nagasaka, Akihiko; Hirose, Ayako [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

2000-01-01

This report deals with the result of the experiment that 8 subjects had executed adding task and search task. They executed each task in 80 minutes under 5 conditions: (1) with no rest, and with 4 kinds of 20 minutes rests, in which they (2) opened eyes, (3) closed eyes, (4) closed eyes with listening classic music and (5) closed eyes with feet massage, in the middle of the task. The results of analysis of variance with the task performance in the latter half, there were significant differences between each condition with every subject in adding task, and with 6 subjects in search task. However, the orders of the task performance with each condition were not the same by each subject. It was suggested that transition of the arousal levels under the rest was related to the effects of the rest rather than the subjects' taste in rests. In the rest, the percentage of {alpha} wave of electroencephalogram and the coefficient of variation of R-R interval (time interval of heart beats) were increased than in executing task. The mean Kendall's rank correlation of coefficient with the order of increase rate of {alpha}/{beta} wave and the task performance in the latter half was slightly negative in adding task, but was about 0.4 in search task. From these results, about six requirements for 'an effective rest' were able to be mentioned, for example, 'the devices that raises the arousal levels is carried out just before a rest end'. (author)

Petechiae: reproducible pattern of distribution and increased appearance after bed rest.

Science.gov (United States)

Ganse, Bergita; Limper, Ulrich; Bühlmeier, Judith; Rittweger, Jörn

2013-08-01

Exposure to acceleration can cause petechial hemorrhages, called G measles. Petechiae usually start to develop between 5 and 9 G with a high interindividual variance. Centrifuge training delays the onset to higher G levels. One might expect onset at lower G levels after bed rest; however, there is no evidence in the literature. A case of petechiae formation after bed rest is presented here. Orthostatic tolerance was tested using a tilt table and lower body negative pressure before and after bed rest in both campaigns of a 2 x 21-d bed rest study with 6 degrees head-down tilt. A 42-yr-old male Caucasian without any history of thrombosis, venous disease, hemorrhage, or petechiae, and with a negative thrombophilia screening, took part in the bed rest study as 1 out of 10 subjects. He was the only one to develop petechiae during the orthostatic tests after, but not before, bed rest in both campaigns. Petechiae were distributed throughout the lower legs and most pronounced at the shin in a stocking-like fashion, surprisingly reoccurring in an identical pattern of distribution. Petechiae appeared slowly over minutes during hyperemia. This case indicates that prolonged bed rest decreases the threshold for petechiae formation. A reproducible distribution pattern suggests that factors predisposing to petechiae formation keep their local distribution over time (possibly due to local vessel structures). Mechanisms of adaptation and interindividual variance are unclear. Findings are of clinical relevance as such cases might occur after prolonged bed rest in patients without need of expensive testing.

Atomic nanoscale technology in the nuclear industry

CERN Document Server

Woo, Taeho

2011-01-01

Developments at the nanoscale are leading to new possibilities and challenges for nuclear applications in areas ranging from medicine to international commerce to atomic power production/waste treatment. Progress in nanotech is helping the nuclear industry slash the cost of energy production. It also continues to improve application reliability and safety measures, which remain a critical concern, especially since the reactor disasters in Japan. Exploring the new wide-ranging landscape of nuclear function, Atomic Nanoscale Technology in the Nuclear Industry details the breakthroughs in nanosca

Reduced resting state functional connectivity of the somatosensory cortex predicts psychopathological symptoms in women with bulimia nervosa

Directory of Open Access Journals (Sweden)

Luca eLavagnino

2014-08-01

Full Text Available BackgroundAlterations in the resting state functional connectivity (rs-FC of several brain networks have been demonstrated in eating disorders. However, very few studies are currently available on brain network dysfunctions in bulimia nervosa (BN. The somatosensory network is central in processing body-related stimuli and it may be altered in BN. The present study therefore aimed to investigate rs-FC in the somatosensory network in bulimic women. MethodsSixteen medication-free women with BN (age=23±5 years and 18 matched controls (age=23±3 years underwent a functional magnetic resonance resting state scan and assessment of eating disorder symptoms. Within-network and seed-based functional connectivity analyses were conducted to assess rs-FC within the somatosensory network and to other areas of the brain. ResultsBN patients showed a decreased resting state functional connectivity both within the somatosensory network (t=9.0, df=1, P=0.005 and with posterior cingulate cortex (PCC and two visual areas (the right middle occipital gyrus and the right cuneus(P=0.05 corrected for multiple comparison. The region in the right middle occipital gyrus is implicated in body processing and is known as extrastriate body area, or EBA. The rs-FC of the left paracentral lobule with the EBA correlated with psychopathology measures like bulimia (r=-0.4; P=0.02 and interoceptive awareness (r=-0.4; P=0.01. Analyses were conducted using age, BMI (body mass index and depressive symptoms as covariates. ConclusionsOur findings show a specific alteration of the rs-FC of the somatosensory cortex in BN patients, which correlates with eating disorder symptoms. The connectivity between the somatosensory cortex and the EBA might be related to dysfunctions in body image processing. The results should be considered preliminary due to the small sample size.

A compact and realistic cerebral cortical layout derived from prewhitened resting-state fMRI time series: Cherniak's adjacency rule, size law, and metamodule grouping upheld.

Science.gov (United States)

Lewis, Scott M; Christova, Peka; Jerde, Trenton A; Georgopoulos, Apostolos P

2012-01-01

We used hierarchical tree clustering to derive a functional organizational chart of 52 human cortical areas (26 per hemisphere) from zero-lag correlations calculated between single-voxel, prewhitened, resting-state BOLD fMRI time series in 18 subjects. No special "resting-state networks" were identified. There were four major features in the resulting tree (dendrogram). First, there was a strong clustering of homotopic, left-right hemispheric areas. Second, cortical areas were concatenated in multiple, partially overlapping clusters. Third, the arrangement of the areas revealed a layout that closely resembled the actual layout of the cerebral cortex, namely an orderly progression from anterior to posterior. And fourth, the layout of the cortical areas in the tree conformed to principles of efficient, compact layout of components proposed by Cherniak. Since the tree was derived on the basis of the strength of neural correlations, these results document an orderly relation between functional interactions and layout, i.e., between structure and function.

A compact and realistic cerebral cortical layout derived from prewhitened resting-state fMRI time series: Cherniak's adjacency rule, size law, and metamodule grouping upheld

Science.gov (United States)

Lewis, Scott M.; Christova, Peka; Jerde, Trenton A.; Georgopoulos, Apostolos P.

2012-01-01

We used hierarchical tree clustering to derive a functional organizational chart of 52 human cortical areas (26 per hemisphere) from zero-lag correlations calculated between single-voxel, prewhitened, resting-state BOLD fMRI time series in 18 subjects. No special “resting-state networks” were identified. There were four major features in the resulting tree (dendrogram). First, there was a strong clustering of homotopic, left-right hemispheric areas. Second, cortical areas were concatenated in multiple, partially overlapping clusters. Third, the arrangement of the areas revealed a layout that closely resembled the actual layout of the cerebral cortex, namely an orderly progression from anterior to posterior. And fourth, the layout of the cortical areas in the tree conformed to principles of efficient, compact layout of components proposed by Cherniak. Since the tree was derived on the basis of the strength of neural correlations, these results document an orderly relation between functional interactions and layout, i.e., between structure and function. PMID:22973198

Atomic scale characterization of white etching area and its adjacent matrix in a martensitic 100Cr6 bearing steel

Energy Technology Data Exchange (ETDEWEB)

Li, Y.J., E-mail: y.li@mpie.de [Max-Planck Institut für Eisenforschung, Max-Planck-Str. 1, Düsseldorf D-40237 (Germany); Center for Interface-Dominated High Performance Materials, Ruhr-Universität Bochum, Bochum 44780 (Germany); Herbig, M.; Goto, S. [Max-Planck Institut für Eisenforschung, Max-Planck-Str. 1, Düsseldorf D-40237 (Germany); Raabe, D., E-mail: d.raabe@mpie.de [Max-Planck Institut für Eisenforschung, Max-Planck-Str. 1, Düsseldorf D-40237 (Germany)

2017-01-15

Atom probe tomography was employed to characterize the microstructure and C distribution in the white etching area (WEA) of a martensitic 100Cr6 bearing steel subjected to rolling contact fatigue. Different from its surrounding matrix where a plate-like martensitic structure prevails, the WEA exhibits equiaxed grains with a uniform grain size of about 10 nm. Significant C grain boundary enrichment (>7.5at.%) and an overall higher C concentration than the nominal value are observed in the WEA. These results suggest that the formation of WEA results from severe local plastic deformation that causes dissolution of carbides and the redistribution of C. - Highlights: •APT has been applied to characterize the microstructure of white etching area (WEA). •Quantitative analyses of C distribution indicate that carbides are dissolved on the WEA. •WEA contains equiaxed grains with a uniform grain size of 10 nm. •C segregation at grain boundaries stabilizes the nanosized grain structure. •Formation of WEA is explained by severe local plastic deformation introduced by cyclic contact loading.

Feeding during the resting phase causes profound changes in physiology and desynchronization between liver and muscle rhythms of rats

NARCIS (Netherlands)

Opperhuizen, Anne-Loes; Wang, Dawei; Foppen, E.; Jansen, Remi; Boudzovitch-Surovtseva, Olga; de Vries, Janneke; Fliers, Eric; Kalsbeek, A.

2016-01-01

Shiftworkers run an increased risk of developing metabolic disorders, presumably as a result of disturbed circadian physiology. Eating at a time-of-day that is normally dedicated to resting and fasting, may contribute to this association. The hypothalamus is the key brain area that integrates

Towards a Process Calculus for Rest: Current State of the Art

Directory of Open Access Journals (Sweden)

Dwornikowski Dariusz

2015-12-01

Full Text Available SOA is a popular paradigm for building distributed systems that has gained a great recognition over past years. There are two main approaches to implementing SOA: SOAP-based and RESTful Web services. In order to address problems of modeling and verification of Web services, several process calculi have been proposed for SOAP-based Web services but none for the RESTful Web services based systems. This article is a comparative survey on existing process calculi for SOA systems, also the existing attempts to formalize REST systems are discussed. The aim of the article is to see how process calculi for SOAP-based systems deal with different aspects of their modeling domain, and whether their approaches can be used to model RESTful and ROA systems. Finally, basing on the survey, requirements for a new process calculus specific for REST are defined.

Influence of Anodal Transcranial Direct Current Stimulation (tDCS) over the Right Angular Gyrus on Brain Activity during Rest

Science.gov (United States)

Clemens, Benjamin; Jung, Stefanie; Mingoia, Gianluca; Weyer, David; Domahs, Frank; Willmes, Klaus

2014-01-01

Although numerous studies examined resting-state networks (RSN) in the human brain, so far little is known about how activity within RSN might be modulated by non-invasive brain stimulation applied over parietal cortex. Investigating changes in RSN in response to parietal cortex stimulation might tell us more about how non-invasive techniques such as transcranial direct current stimulation (tDCS) modulate intrinsic brain activity, and further elaborate our understanding of how the resting brain responds to external stimulation. Here we examined how activity within the canonical RSN changed in response to anodal tDCS applied over the right angular gyrus (AG). We hypothesized that changes in resting-state activity can be induced by a single tDCS session and detected with functional magnetic resonance imaging (fMRI). Significant differences between two fMRI sessions (pre-tDCS and post-tDCS) were found in several RSN, including the cerebellar, medial visual, sensorimotor, right frontoparietal, and executive control RSN as well as the default mode and the task positive network. The present results revealed decreased and increased RSN activity following tDCS. Decreased RSN activity following tDCS was found in bilateral primary and secondary visual areas, and in the right putamen. Increased RSN activity following tDCS was widely distributed across the brain, covering thalamic, frontal, parietal and occipital regions. From these exploratory results we conclude that a single session of anodal tDCS over the right AG is sufficient to induce large-scale changes in resting-state activity. These changes were localized in sensory and cognitive areas, covering regions close to and distant from the stimulation site. PMID:24760013

Influence of anodal transcranial direct current stimulation (tDCS) over the right angular gyrus on brain activity during rest.

Science.gov (United States)

Clemens, Benjamin; Jung, Stefanie; Mingoia, Gianluca; Weyer, David; Domahs, Frank; Willmes, Klaus

2014-01-01

Although numerous studies examined resting-state networks (RSN) in the human brain, so far little is known about how activity within RSN might be modulated by non-invasive brain stimulation applied over parietal cortex. Investigating changes in RSN in response to parietal cortex stimulation might tell us more about how non-invasive techniques such as transcranial direct current stimulation (tDCS) modulate intrinsic brain activity, and further elaborate our understanding of how the resting brain responds to external stimulation. Here we examined how activity within the canonical RSN changed in response to anodal tDCS applied over the right angular gyrus (AG). We hypothesized that changes in resting-state activity can be induced by a single tDCS session and detected with functional magnetic resonance imaging (fMRI). Significant differences between two fMRI sessions (pre-tDCS and post-tDCS) were found in several RSN, including the cerebellar, medial visual, sensorimotor, right frontoparietal, and executive control RSN as well as the default mode and the task positive network. The present results revealed decreased and increased RSN activity following tDCS. Decreased RSN activity following tDCS was found in bilateral primary and secondary visual areas, and in the right putamen. Increased RSN activity following tDCS was widely distributed across the brain, covering thalamic, frontal, parietal and occipital regions. From these exploratory results we conclude that a single session of anodal tDCS over the right AG is sufficient to induce large-scale changes in resting-state activity. These changes were localized in sensory and cognitive areas, covering regions close to and distant from the stimulation site.

Atom optics

International Nuclear Information System (INIS)

Balykin, V. I.; Jhe, W.

1999-01-01

Atom optics, in analogy to neutron and electron optics, deals with the realization of as a traditional elements, such as lenes, mirrors, beam splitters and atom interferometers, as well as a new 'dissipative' elements such as a slower and a cooler, which have no analogy in an another types of optics. Atom optics made the development of atom interferometer with high sensitivity for measurement of acceleration and rotational possible. The practical interest in atom optics lies in the opportunities to create atom microprobe with atom-size resolution and minimum damage of investigated objects. (Cho, G. S.)

Resting-state EEG, impulsiveness, and personality in daily and nondaily smokers.

Science.gov (United States)

Rass, Olga; Ahn, Woo-Young; O'Donnell, Brian F

2016-01-01

Resting EEG is sensitive to transient, acute effects of nicotine administration and abstinence, but the chronic effects of smoking on EEG are poorly characterized. This study measures the resting EEG profile of chronic smokers in a non-deprived, non-peak state to test whether differences in smoking behavior and personality traits affect pharmaco-EEG response. Resting EEG, impulsiveness, and personality measures were collected from daily smokers (n=22), nondaily smokers (n=31), and non-smokers (n=30). Daily smokers had reduced resting delta and alpha EEG power and higher impulsiveness (Barratt Impulsiveness Scale) compared to nondaily smokers and non-smokers. Both daily and nondaily smokers discounted delayed rewards more steeply, reported lower conscientiousness (NEO-FFI), and reported greater disinhibition and experience seeking (Sensation Seeking Scale) than non-smokers. Nondaily smokers reported greater sensory hedonia than nonsmokers. Altered resting EEG power in daily smokers demonstrates differences in neural signaling that correlated with greater smoking behavior and dependence. Although nondaily smokers share some characteristics with daily smokers that may predict smoking initiation and maintenance, they differ on measures of impulsiveness and resting EEG power. Resting EEG in non-deprived chronic smokers provides a standard for comparison to peak and trough nicotine states and may serve as a biomarker for nicotine dependence, relapse risk, and recovery. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Resting-state EEG, Impulsiveness, and Personality in Daily and Nondaily Smokers†

Science.gov (United States)

Rass, Olga; Ahn, Woo-Young; O’Donnell, Brian F.

2015-01-01

Objectives Resting EEG is sensitive to transient, acute effects of nicotine administration and abstinence, but the chronic effects smoking on EEG are poorly characterized. This study measures the resting EEG profile of chronic smokers in a non-deprived, non-peak state to test whether differences in smoking behavior and personality traits affect pharmaco-EEG response. Methods Resting EEG, impulsiveness, and personality measures were collected from daily smokers (n=22), nondaily smokers (n=31), and non-smokers (n=30). Results Daily smokers had reduced resting delta and alpha EEG power and higher impulsiveness (Barratt Impulsiveness Scale) compared to nondaily smokers and non-smokers. Both daily and nondaily smokers discounted delayed rewards more steeply, reported lower conscientiousness (NEO-FFI) and reported greater disinhibition and experience seeking (Sensation Seeking Scale) than non-smokers. Nondaily smokers reported greater sensory hedonia than nonsmokers. Conclusions Altered resting EEG power in daily smokers demonstrates differences in neural signaling that correlated with greater smoking behavior and dependence. Although nondaily smokers share some characteristics with daily smokers that may predict smoking initiation and maintenance, they differ on measures of impulsiveness and resting EEG power. Significance Resting EEG in non-deprived chronic smokers provides a standard for comparison to peak and trough nicotine states and may serve as a biomarker for nicotine dependence, relapse risk, and recovery. PMID:26051750

Directed Atom-by-Atom Assembly of Dopants in Silicon.

Science.gov (United States)

Hudak, Bethany M; Song, Jiaming; Sims, Hunter; Troparevsky, M Claudia; Humble, Travis S; Pantelides, Sokrates T; Snijders, Paul C; Lupini, Andrew R

2018-05-17

The ability to controllably position single atoms inside materials is key for the ultimate fabrication of devices with functionalities governed by atomic-scale properties. Single bismuth dopant atoms in silicon provide an ideal case study in view of proposals for single-dopant quantum bits. However, bismuth is the least soluble pnictogen in silicon, meaning that the dopant atoms tend to migrate out of position during sample growth. Here, we demonstrate epitaxial growth of thin silicon films doped with bismuth. We use atomic-resolution aberration-corrected imaging to view the as-grown dopant distribution and then to controllably position single dopants inside the film. Atomic-scale quantum-mechanical calculations corroborate the experimental findings. These results indicate that the scanning transmission electron microscope is of particular interest for assembling functional materials atom-by-atom because it offers both real-time monitoring and atom manipulation. We envision electron-beam manipulation of atoms inside materials as an achievable route to controllable assembly of structures of individual dopants.

Atomic weight versus atomic mass controversy

International Nuclear Information System (INIS)

Holden, N.E.

1985-01-01

A problem for the Atomic Weights Commission for the past decade has been the controversial battle over the names ''atomic weight'' and ''atomic mass''. The Commission has considered the arguments on both sides over the years and it appears that this meeting will see more of the same discussion taking place. In this paper, I review the situation and offer some alternatives

SASP - Symposium on atomic, cluster and surface physics `94

Energy Technology Data Exchange (ETDEWEB)

Maerk, T D; Schrittwieser, R; Smith, D

1994-12-31

This international symposium (Founding Chairman: W. Lindinger, Innsbruck) is one in a continuing biennial series of conferences which seeks to promote the growth of scientific knowledge and its effective exchange among scientists in the field of atomic, molecular, cluster and surface physics and related areas. The symposium deals in particular with interactions between ions, electrons, photons, atoms, molecules, and clusters and their interactions with surfaces. (author).

Charge breeding investigation in EBIS/T and collision study of ions with cold atoms for HITRAP

Energy Technology Data Exchange (ETDEWEB)

Sokolov, Alexey

2010-01-29

Highly charged ions (HCI) at low velocities or at rest are interesting systems for various atomic physics experiments. For investigations on HCI of heavy stable or radioactive nuclides the HITRAP (Highly charged Ion TRAP) decelerator facility has been set up at GSI to deliver cooled beams of HCI at an energy of 5 keV/q. The HCI are produced in a stripper foil at relativistic energies and are decelerated in several steps at ESR storage ring and HITRAP before they are delivered to experimental setups. One of the experiments is the investigation of multi-electron charge exchange in collisions of heavy HCI with cold atoms using novel MOTRIMS technique. Collision experiments on light ions from an ECR ion source colliding with cold atoms in a MOT have been performed and the results are described. An electron beam ion trap (EBIT) has been tested and optimized for commissioning of the HITRAP physics experiments. The process of charge breeding in the EBIT has been successfully studied with gaseous elements and with an alkaline element injected from an external ion source. (orig.)

Charge breeding investigation in EBIS/T and collision study of ions with cold atoms for HITRAP

International Nuclear Information System (INIS)

Sokolov, Alexey

2010-01-01

Highly charged ions (HCI) at low velocities or at rest are interesting systems for various atomic physics experiments. For investigations on HCI of heavy stable or radioactive nuclides the HITRAP (Highly charged Ion TRAP) decelerator facility has been set up at GSI to deliver cooled beams of HCI at an energy of 5 keV/q. The HCI are produced in a stripper foil at relativistic energies and are decelerated in several steps at ESR storage ring and HITRAP before they are delivered to experimental setups. One of the experiments is the investigation of multi-electron charge exchange in collisions of heavy HCI with cold atoms using novel MOTRIMS technique. Collision experiments on light ions from an ECR ion source colliding with cold atoms in a MOT have been performed and the results are described. An electron beam ion trap (EBIT) has been tested and optimized for commissioning of the HITRAP physics experiments. The process of charge breeding in the EBIT has been successfully studied with gaseous elements and with an alkaline element injected from an external ion source. (orig.)

Intensive Exercise Training During Bed Rest Attenuates Deconditioning

Science.gov (United States)

Greenleaf, John E.

1997-01-01

Intensive exercise training during bed rest attenuates deconditioning. Med. Sci. Sports Exerc., Vol. 29, No. 2, pp. 207-215, 1997. A 30-d 6 deg head-down bed rest project was conducted to evaluate variable high-intensity, short-duration, isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent resistive isokinetic exercise (IKE) training regimens designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (adaptive) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Major findings are summarized in this paper. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volumes, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (f) attenuated the decrease in peak VO2 by 50%, (g) attenuated loss of red cell volume by 40% but had no effect on loss of plasma volume, (b) induced positive body water balance, (i) had no adverse effect on quality of sleep or concentration, and 0) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regimens and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.

Outer-shell transitions in collisions between multiply charged ions and atoms

International Nuclear Information System (INIS)

Bloemen, E.W.P.

1980-01-01

The study of collisions between multiply charged ions and atoms (molecules) is of importance in different areas of research. Usually, the most important process is capture of an electron from the target atom into the projectile ion. In most cases the electron goes to an excited state of the projectile ion. These electron capture processes are studied. The author also studied direct excitation of the target atom and of the projectile ion. (Auth.)

The impacts of multiple rest-break periods on commercial truck driver's crash risk.

Science.gov (United States)

Chen, Chen; Xie, Yuanchang

2014-02-01

Driver fatigue has been a major contributing factor to fatal commercial truck crashes, which accounted for about 10% of all fatal motor vehicle crashes that happened between 2009 and 2011. Commercial truck drivers' safety performance can deteriorate easily due to fatigue caused by long driving hours and irregular working schedules. To ensure safety, truck drivers often use off-duty time and short rest breaks during a trip to recover from fatigue. This study thoroughly investigates the impacts of off-duty time prior to a trip and short rest breaks on commercial truck safety by using Cox proportional hazards model and Andersen-Gill model. It is found that increasing total rest-break duration can consistently reduce fatigue-related crash risk. Similarly, taking more rest breaks can help to reduce crash risk. The results suggest that two rest breaks are generally considered enough for a 10-hour trip, as three or more rest breaks may not further reduce crash risk substantially. Also, the length of each rest break does not need to be very long and 30min is usually adequate. In addition, this study investigates the safety impacts of when to take rest breaks. It is found that taking rest breaks too soon after a trip starts will cause the rest breaks to be less effective. The findings of this research can help policy makers and trucking companies better understand the impacts of multiple rest-break periods and develop more effective rules to improve the safety of truck drivers. Copyright © 2014 Elsevier Ltd and National Safety Council. All rights reserved.

Rest delayed images on 99mTc-MIBI myocardial SPECT as a noninvasive screen for the diagnosis of vasospastic angina pectoris

International Nuclear Information System (INIS)

Ono, Soichi; Yamaguchi, Hiroyuki; Takayama, Shin; Kurabe, Atsushi; Heito, Takayuki

2002-01-01

Diagnostic usefulness of 99m Tc-hexakis-2-methoxy isobutyl isonitrile (MIBI) myocardial SPECT at rest was examined in 39 cases of coronary vasospastic angina pectoris who were diagnosed by a positive reaction to ergonovine provocation. SPECT was performed 45 minutes (early image) and 3 hours (delayed image) after the intravenous injection of approximately 600 MBq of MIBI. Decrease in accumulation was ranked by four defect scores (0: normal; 1: slight decrease; 2: moderate decrease; 3: severe decrease) and the total defect score was evaluated semiquantitatively. The washout rate between the normal area and the spasm area was also evaluated quantitatively using bull's eye. As a result, 15 cases (15/39; 38.4%) showed decreased accumulation in the early image and 27 cases (27/39; 69.2%) showed decreased accumulation in the delayed image. All of the cases which showed decreased accumulation in the early image had decreased accumulation in the delayed image as well. In 6 cases (6/34; 17.6%) showed ST wave changes during exercise ECG and 16 cases (16/34: 47%) showed decreased accumulation in the exercise myocardial SPECT. The washout rate of MIBI in the decreased accumulation area was significantly higher than that of the normal area. Of 32 ergonovine induced vasospastic area, 23 areas (72%) exhibited decreased accumulation in the delayed image for the same area. Decreased accumulation in the delayed image in MIBI was due to the enhanced washout, which, in turn, indicated declined retention of MIBI by mitochondrial membrane. In coronary vasospastic angina pectoris, spasm induced ischemia was thought to have an effect on the mitochondria. This study suggested that even with a normal exercise ECG and exercise myocardial SPECT, there's a strong possibility of coronary vasospastic angina pectoris if a decreased accumulation was found in the delayed image in the MIBI myocardial SPECT at rest. Hence, in diagnosing coronary vasospastic angina pectoris, the delayed image in the

Para un canon de marginales, malos y malditos: Jaime Rest en CEAL y Ediciones Librerías Fausto

Directory of Open Access Journals (Sweden)

Maximiliano Crespi

2009-11-01

Full Text Available This paper seeks to account for the link between the last period in Jaime Rest's criticism and his work both on the editorial project of Centro Editor de América Latina and on the design of the 'Novel and Short Story' catalog of Ediciones Librerías Fausto. Rest's critical production between the mid 60s and the late 70s is examined, and a detailed description of his work as editor during the same period is presented. The purpose of such comparison is to establish relationships of contiguity and interference between the two areas of work in the context of a cultural and intellectual field marked by repression and censorship

Quantitative MRI comparison of systemic hemodynamics in Mustard/Senning repaired patients and healthy volunteers at rest

International Nuclear Information System (INIS)

Laffon, Eric; Jimenez, Maria; Choussat, Alain; Latrabe, Valerie; Ducassou, Dominique; Marthan, Roger; Laurent, Francois

2004-01-01

The purpose of the present study was to non-invasively compare ascending aortic blood flow and cross-sectional area (CSA) variations vs time in Mustard or Senning repaired (MSR) patients against those of healthy volunteers at rest. Velocity-encoded MR imaging was performed in 10 male patients (age range 18-24 years, median age 20.5 years) late after a Mustard or Senning correction, and in 10 male healthy volunteers (age range 21-25 years, median age 22.5 years), at the upper part of the ascending aorta. Both aortic cross-sectional area (CSA) and blood-flow variations were recorded over a complete cardiac cycle, with a 30-ms time of resolution. The body-surface area (BSA), the mean CSA over the systolic phase, and the BSA-normalized systemic ventricle power and work were significantly lower in the patient series compared with those of the volunteer series. The BSA-normalized right ventricle (RV) power and work of MSR patients were equal to 87 and 83% on average of those of the left ventricle (LV) of healthy volunteers. We conclude that, at rest, the mechanical performance of the systemic RV in MSR patients is significantly lower than that of the LV in healthy volunteers. Furthermore, the significantly lower aortic CSA found in MSR patients than in healthy volunteers may reveal an increase in the vasomotor tone. (orig.)

Angular momentum coupling in atom-atom collisions

International Nuclear Information System (INIS)

Grosser, J.

1986-01-01

The coupling between the electronic angular momentum and the rotating atom-atom axis in the initial or the final phase of an atom-atom collision is discussed, making use of the concepts of radial and rotational (Coriolis) coupling between different molecular states. The description is based on a limited number of well-understood approximations, and it allows an illustrative geometric representation of the transition from the body fixed to the space fixed motion of the electrons. (orig.)

Branched-chain amino acid supplementation during bed rest: effect on recovery

Science.gov (United States)

Stein, T. P.; Donaldson, M. R.; Leskiw, M. J.; Schluter, M. D.; Baggett, D. W.; Boden, G.

2003-01-01

Bed rest is associated with a loss of protein from the weight-bearing muscle. The objectives of this study are to determine whether increasing dietary branched-chain amino acids (BCAAs) during bed rest improves the anabolic response after bed rest. The study consisted of a 1-day ambulatory period, 14 days of bed rest, and a 4-day recovery period. During bed rest, dietary intake was supplemented with either 30 mmol/day each of glycine, serine, and alanine (group 1) or with 30 mmol/day each of the three BCAAs (group 2). Whole body protein synthesis was determined with U-(15)N-labeled amino acids, muscle, and selected plasma protein synthesis with l-[(2)H(5)]phenylalanine. Total glucose production and gluconeogenesis from alanine were determined with l-[U-(13)C(3)]alanine and [6,6-(2)H(2)]glucose. During bed rest, nitrogen (N) retention was greater with BCAA feeding (56 +/- 6 vs. 26 +/- 12 mg N. kg(-1). day(-1), P BCAA supplementation on either whole body, muscle, or plasma protein synthesis or the rate of 3-MeH excretion. Muscle tissue free amino acid concentrations were increased during bed rest with BCAA (0.214 +/- 0.066 vs. 0.088 +/- 0.12 nmol/mg protein, P BCAA group in the recovery phase. In conclusion, the improved N retention during bed rest is due, at least in part, to accretion of amino acids in the tissue free amino acid pools. The amount accreted is not enough to impact protein kinetics in the recovery phase but does improve N retention by providing additional essential amino acids in the early recovery phase.

The influence of rest period instructions on the default mode network

Directory of Open Access Journals (Sweden)

Christopher eBenjamin

2010-12-01

Full Text Available The default mode network (DMN refers to regional brain activity that is greater during rest periods than during attention-demanding tasks and many studies have reported DMN alterations in patient populations. It has also been shown that the DMN is suppressed by scanner background noise (SBN, which is the noise produced by functional magnetic resonance imaging (fMRI. However, it is unclear whether different approaches to rest in the noisy MR environment can alter the DMN and constitute a confound in studies investigating the DMN in particular patient populations (e.g., individuals with schizophrenia, Alzheimer’s disease. We examined twenty-seven healthy adult volunteers who completed an fMRI experiment with 3 different instructions for rest: (1 relax and be still, (2 attend to SBN, or (3 ignore SBN. Region of interest (ROI analyses were performed to determine the influence of rest period instructions on core regions of the DMN and DMN regions previously reported to be altered in patients with or at risk for Alzheimer’s disease or schizophrenia. The dorsal medial prefrontal cortex (dmPFC exhibited greater activity when specific resting instructions were given (i.e. attend to or ignore SBN compared to when non-specific resting instructions were given. Condition-related differences in connectivity were also observed between regions of the dmPFC and inferior parietal/posterior superior temporal cortex. We conclude that rest period instructions and SBN levels should be carefully considered for fMRI studies on the DMN, especially studies on clinical populations and groups that may have different approaches to rest, such as first-time research participants and children.

Altered default network resting-state functional connectivity in adolescents with Internet gaming addiction.

Directory of Open Access Journals (Sweden)

Wei-na Ding

Full Text Available Excessive use of the Internet has been linked to a variety of negative psychosocial consequences. This study used resting-state functional magnetic resonance imaging (fMRI to investigate whether functional connectivity is altered in adolescents with Internet gaming addiction (IGA.Seventeen adolescents with IGA and 24 normal control adolescents underwent a 7.3 minute resting-state fMRI scan. Posterior cingulate cortex (PCC connectivity was determined in all subjects by investigating synchronized low-frequency fMRI signal fluctuations using a temporal correlation method. To assess the relationship between IGA symptom severity and PCC connectivity, contrast images representing areas correlated with PCC connectivity were correlated with the scores of the 17 subjects with IGA on the Chen Internet Addiction Scale (CIAS and Barratt Impulsiveness Scale-11 (BIS-11 and their hours of Internet use per week.There were no significant differences in the distributions of the age, gender, and years of education between the two groups. The subjects with IGA showed longer Internet use per week (hours (p<0.0001 and higher CIAS (p<0.0001 and BIS-11 (p = 0.01 scores than the controls. Compared with the control group, subjects with IGA exhibited increased functional connectivity in the bilateral cerebellum posterior lobe and middle temporal gyrus. The bilateral inferior parietal lobule and right inferior temporal gyrus exhibited decreased connectivity. Connectivity with the PCC was positively correlated with CIAS scores in the right precuneus, posterior cingulate gyrus, thalamus, caudate, nucleus accumbens, supplementary motor area, and lingual gyrus. It was negatively correlated with the right cerebellum anterior lobe and left superior parietal lobule.Our results suggest that adolescents with IGA exhibit different resting-state patterns of brain activity. As these alterations are partially consistent with those in patients with substance addiction, they support the

Structural connectivity allows for multi-threading during rest: the structure of the cortex leads to efficient alternation between resting state exploratory behavior and default mode processing.

Science.gov (United States)

Senden, Mario; Goebel, Rainer; Deco, Gustavo

2012-05-01

Despite the absence of stimulation or task conditions the cortex exhibits highly structured spatio-temporal activity patterns. These patterns are known as resting state networks (RSNs) and emerge as low-frequency fluctuations (rest. We are interested in the relationship between structural connectivity of the cortex and the fluctuations exhibited during resting conditions. We are especially interested in the effect of degree of connectivity on resting state dynamics as the default mode network (DMN) is highly connected. We find in experimental resting fMRI data that the DMN is the functional network that is most frequently active and for the longest time. In large-scale computational simulations of the cortex based on the corresponding underlying DTI/DSI based neuroanatomical connectivity matrix, we additionally find a strong correlation between the mean degree of functional networks and the proportion of time they are active. By artificially modifying different types of neuroanatomical connectivity matrices in the model, we were able to demonstrate that only models based on structural connectivity containing hubs give rise to this relationship. We conclude that, during rest, the cortex alternates efficiently between explorations of its externally oriented functional repertoire and internally oriented processing as a consequence of the DMN's high degree of connectivity. Copyright © 2012 Elsevier Inc. All rights reserved.

Laser cooling of atoms and ions

International Nuclear Information System (INIS)

Morigi, G.

1999-02-01

introduction, which puts it into the context of the past and present scientific debate, and then the work itself which, in the cases where it has already appeared in a scientific journal, is presented in the form of the publication. More in detail, the introductory chapter deals first briefly with laser cooling of free atoms and then more comprehensively with laser cooling of trapped atoms, giving particular attention to the basic concepts and mechanisms which are recurrent throughout the rest of the thesis. At the end of the first chapter I give a discussion on the laser cooling of many atoms and ions, summarizing the state of the art and the applications currently under discussion, such as degenerate atomic gases and implementations of quantum information processing. The second and third chapters discuss schemes of laser cooling of single trapped atoms or ions to the motional ground state of a trap. These schemes are designed to be efficient in the regime where the amplitude of the particle's motion is comparable with the laser wavelength. In particular the scheme described in chapter II is a modification of sideband cooling and it considerably extends the efficiency of this technique to a wider range of trapping conditions. In chapter III a dark state cooling mechanism is presented, where the dark state is obtained in real space. Both schemes are demonstrated to be effective methods for preparing atoms in the ground state of a trapping potential. Chapter IV and chapter V focus on the problem of cooling more than one trapped ion, taking into account their Coulomb interaction, for trapping conditions which are typical for quantum information experiments. Chapter IV concentrates more on laser cooling to the ground state by means of sideband cooling, whereas in chapter V the theoretical problem of Doppler cooling of interacting trapped ions is discussed. (author)

Variations in resting energy expenditure: impact on gestational weight gain.

Science.gov (United States)

Berggren, E K; O'Tierney-Ginn, P; Lewis, S; Presley, L; De-Mouzon, S Hauguel; Catalano, P M

2017-10-01

There are significant variations in gestational weight gain, with many women gaining in excess of the Institute of Medicine guidelines. Unfortunately, efforts to improve appropriate gestational weight gain have had only limited success. To date, interventions have focused primarily on decreasing energy intake and/or increasing physical activity. Maternal resting energy expenditure, which comprises ∼60% of total energy expenditure compared with the ∼20% that comes from physical activity, may be an important consideration in understanding variations in gestational weight gain. Our objective was to quantify the changes in resting energy expenditure during pregnancy and their relationship to gestational weight gain and body composition changes among healthy women. We hypothesized that greater gestational weight gain, and fat mass accrual in particular, are inversely related to variations in resting energy expenditure. We conducted a secondary analysis of a prospective cohort studied before conception and late pregnancy (34-36 weeks). Body composition (estimated using hydrodensitometry) and resting energy expenditure (estimated using indirect calorimetry) were measured. The relationship between the changes in resting energy expenditure and gestational weight gain and the change in fat mass and fat-free mass were quantified. Resting energy expenditure was expressed as kilocalories per kilogram of fat-free mass per day (kilocalories per kilogram of fat-free mass -1 /day -1 ) and kilocalories per day. Correlations are reported as r. Among 51 women, preconception body mass index was 23.0 (4.7) kg/m 2 ; gestational weight gain was 12.8 (4.7) kg. Preconception and late pregnancy resting energy expenditure (kilocalories per day) correlated positively with the change in fat-free mass (r = 0.37, P = .008; r = 0.51, P = .001). Late-pregnancy resting energy expenditure (kilocalories per kilogram of fat-free mass -1 /day -1 ) was inversely associated with the change in fat

Proceedings of the ninth Symposium of Atomic Energy Research

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-10-01

The present volume contains 57 papers. Most of the papers were presented on the ninth Symposium of Atomic Energy Research, held in Demanovska Dolina, Slovakia, 4-6 October 1999. The rest of the papers (intended to be presented but not presented due to difficulties) is included based on the decision of the organizers. The papers are in their original form, i. e. no corrections or modifications were carried out. The content of this volume is divided into thematic groups: Spectral and Core Calculation Methods, Core Operation and Fuel Management, Core Monitoring, Surveillance and Testing, Safety Issues, Neutron Kinetics and Reactor Dynamics, Reactivity Evaluation, High Subcriticality, Critical Safety and Spent Fuel and Spent Fuel Transmutations - according to the presentation sequence on the Symposium. At the end of the volume an alphabetical author index is given.

Proceedings of the ninth Symposium of Atomic Energy Research

International Nuclear Information System (INIS)

1999-10-01

The present volume contains 57 papers. Most of the papers were presented on the ninth Symposium of Atomic Energy Research, held in Demanovska Dolina, Slovakia, 4-6 October 1999. The rest of the papers (intended to be presented but not presented due to difficulties) is included based on the decision of the organizers. The papers are in their original form, i. e. no corrections or modifications were carried out. The content of this volume is divided into thematic groups: Spectral and Core Calculation Methods, Core Operation and Fuel Management, Core Monitoring, Surveillance and Testing, Safety Issues, Neutron Kinetics and Reactor Dynamics, Reactivity Evaluation, High Subcriticality, Critical Safety and Spent Fuel and Spent Fuel Transmutations - according to the presentation sequence on the Symposium. At the end of the volume an alphabetical author index is given

Physiological and Functional Alterations after Spaceflight and Bed Rest.

Science.gov (United States)

Mulavara, Ajitkumar P; Peters, Brian T; Miller, Chris A; Kofman, Igor S; Reschke, Millard F; Taylor, Laura C; Lawrence, Emily L; Wood, Scott J; Laurie, Steven S; Lee, Stuart M C; Buxton, Roxanne E; May-Phillips, Tiffany R; Stenger, Michael B; Ploutz-Snyder, Lori L; Ryder, Jeffrey W; Feiveson, Alan H; Bloomberg, Jacob J

2018-04-03

Exposure to microgravity causes alterations in multiple physiological systems, potentially impacting the ability of astronauts to perform critical mission tasks. The goal of this study was to determine the effects of spaceflight on functional task performance and to identify the key physiological factors contributing to their deficits. A test battery comprised of 7 functional tests and 15 physiological measures was used to investigate the sensorimotor, cardiovascular and neuromuscular adaptations to spaceflight. Astronauts were tested before and after 6-month spaceflights. Subjects were also tested before and after 70 days of 6° head-down bed rest, a spaceflight analog, to examine the role of axial body unloading on the spaceflight results. These subjects included Control and Exercise groups to examine the effects of exercise during bed rest. Spaceflight subjects showed the greatest decrement in performance during functional tasks that required the greatest demand for dynamic control of postural equilibrium which was paralleled by similar decrements in sensorimotor tests that assessed postural and dynamic gait control. Other changes included reduced lower limb muscle performance and increased heart rate to maintain blood pressure. Exercise performed during bed rest prevented detrimental change in neuromuscular and cardiovascular function, however, both bed rest groups experienced functional and balance deficits similar to spaceflight subjects. Bed rest data indicates that body support unloading experienced during spaceflight contributes to postflight postural control dysfunction. Further, the bed rest results in the Exercise group of subjects confirm that resistance and aerobic exercises performed during spaceflight can play an integral role in maintaining neuromuscular and cardiovascular function, which can help in reducing decrements in functional performance. These results indicate that a countermeasure to mitigate postflight postural control dysfunction is

Abnormal resting-state connectivity of motor and cognitive networks in early manifest Huntington's disease.

Science.gov (United States)

Wolf, R C; Sambataro, F; Vasic, N; Depping, M S; Thomann, P A; Landwehrmeyer, G B; Süssmuth, S D; Orth, M

2014-11-01

Functional magnetic resonance imaging (fMRI) of multiple neural networks during the brain's 'resting state' could facilitate biomarker development in patients with Huntington's disease (HD) and may provide new insights into the relationship between neural dysfunction and clinical symptoms. To date, however, very few studies have examined the functional integrity of multiple resting state networks (RSNs) in manifest HD, and even less is known about whether concomitant brain atrophy affects neural activity in patients. Using MRI, we investigated brain structure and RSN function in patients with early HD (n = 20) and healthy controls (n = 20). For resting-state fMRI data a group-independent component analysis identified spatiotemporally distinct patterns of motor and prefrontal RSNs of interest. We used voxel-based morphometry to assess regional brain atrophy, and 'biological parametric mapping' analyses to investigate the impact of atrophy on neural activity. Compared with controls, patients showed connectivity changes within distinct neural systems including lateral prefrontal, supplementary motor, thalamic, cingulate, temporal and parietal regions. In patients, supplementary motor area and cingulate cortex connectivity indices were associated with measures of motor function, whereas lateral prefrontal connectivity was associated with cognition. This study provides evidence for aberrant connectivity of RSNs associated with motor function and cognition in early manifest HD when controlling for brain atrophy. This suggests clinically relevant changes of RSN activity in the presence of HD-associated cortical and subcortical structural abnormalities.

Resting state brain dynamics and its transients: a combined TMS-EEG study.

Science.gov (United States)

Bonnard, Mireille; Chen, Sophie; Gaychet, Jérôme; Carrere, Marcel; Woodman, Marmaduke; Giusiano, Bernard; Jirsa, Viktor

2016-08-04

The brain at rest exhibits a spatio-temporally rich dynamics which adheres to systematic behaviours that persist in task paradigms but appear altered in disease. Despite this hypothesis, many rest state paradigms do not act directly upon the rest state and therefore cannot confirm hypotheses about its mechanisms. To address this challenge, we combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to study brain's relaxation toward rest following a transient perturbation. Specifically, TMS targeted either the medial prefrontal cortex (MPFC), i.e. part of the Default Mode Network (DMN) or the superior parietal lobule (SPL), involved in the Dorsal Attention Network. TMS was triggered by a given brain state, namely an increase in occipital alpha rhythm power. Following the initial TMS-Evoked Potential, TMS at MPFC enhances the induced occipital alpha rhythm, called Event Related Synchronisation, with a longer transient lifetime than TMS at SPL, and a higher amplitude. Our findings show a strong coupling between MPFC and the occipital alpha power. Although the rest state is organized around a core of resting state networks, the DMN functionally takes a special role among these resting state networks.

The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy.

Science.gov (United States)

Henselmans, Menno; Schoenfeld, Brad J

2014-12-01

Due to a scarcity of longitudinal trials directly measuring changes in muscle girth, previous recommendations for inter-set rest intervals in resistance training programs designed to stimulate muscular hypertrophy were primarily based on the post-exercise endocrinological response and other mechanisms theoretically related to muscle growth. New research regarding the effects of inter-set rest interval manipulation on resistance training-induced muscular hypertrophy is reviewed here to evaluate current practices and provide directions for future research. Of the studies measuring long-term muscle hypertrophy in groups employing different rest intervals, none have found superior muscle growth in the shorter compared with the longer rest interval group and one study has found the opposite. Rest intervals less than 1 minute can result in acute increases in serum growth hormone levels and these rest intervals also decrease the serum testosterone to cortisol ratio. Long-term adaptations may abate the post-exercise endocrinological response and the relationship between the transient change in hormonal production and chronic muscular hypertrophy is highly contentious and appears to be weak. The relationship between the rest interval-mediated effect on immune system response, muscle damage, metabolic stress, or energy production capacity and muscle hypertrophy is still ambiguous and largely theoretical. In conclusion, the literature does not support the hypothesis that training for muscle hypertrophy requires shorter rest intervals than training for strength development or that predetermined rest intervals are preferable to auto-regulated rest periods in this regard.

Sparse dictionary learning of resting state fMRI networks.

Science.gov (United States)

Eavani, Harini; Filipovych, Roman; Davatzikos, Christos; Satterthwaite, Theodore D; Gur, Raquel E; Gur, Ruben C

2012-07-02

Research in resting state fMRI (rsfMRI) has revealed the presence of stable, anti-correlated functional subnetworks in the brain. Task-positive networks are active during a cognitive process and are anti-correlated with task-negative networks, which are active during rest. In this paper, based on the assumption that the structure of the resting state functional brain connectivity is sparse, we utilize sparse dictionary modeling to identify distinct functional sub-networks. We propose two ways of formulating the sparse functional network learning problem that characterize the underlying functional connectivity from different perspectives. Our results show that the whole-brain functional connectivity can be concisely represented with highly modular, overlapping task-positive/negative pairs of sub-networks.

De Haas-van Alphen effect of a two-dimensional ultracold atomic gas

Science.gov (United States)

Farias, B.; Furtado, C.

2016-01-01

In this paper, we show how the ultracold atom analogue of the two-dimensional de Haas-van Alphen effect in electronic condensed matter systems can be induced by optical fields in a neutral atomic system. The interaction between the suitable spatially varying laser fields and tripod-type trapped atoms generates a synthetic magnetic field which leads the particles to organize themselves in Landau levels. Initially, with the atomic gas in a regime of lowest Landau level, we display the oscillatory behaviour of the atomic energy and its derivative with respect to the effective magnetic field (B) as a function of 1/B. Furthermore, we estimate the area of the Fermi circle of the two-dimensional atomic gas.

Rest and action tremor in Parkinson's disease: effects of Deep Brain Stimulation

NARCIS (Netherlands)

Heida, Tjitske; Wentink, E.C.

2010-01-01

One of the cardinal symptoms of Parkinson’s disease is rest tremor. While rest tremor generally disappears during sleep and voluntary movement, action tremor may be triggered by voluntary movement, and may even be more disabling than rest tremor. Deep brain stimulation (DBS) in the subthalamic

Resting heart rate, physiological stress and disadvantage in Aboriginal and Torres Strait Islander Australians: analysis from a cross-sectional study.

Science.gov (United States)

Zhang, Alice; Hughes, Jaquelyne T; Brown, Alex; Lawton, Paul D; Cass, Alan; Hoy, Wendy; O'Dea, Kerin; Maple-Brown, Louise J

2016-02-11

Lower socioeconomic status has been linked to long-term stress, which can manifest in individuals as physiological stress. The aim was to explore the relationship between low socioeconomic status and physiological stress in Aboriginal and Torres Strait Islander Australians. Using data from the eGFR Study (a cross-sectional study of 634 Indigenous Australians in urban and remote areas of northern and central Australia), we examined associations between resting heart rate and demographic, socioeconomic, and biomedical factors. An elevated resting heart rate has been proposed as a measure of sustained stress activation and was used as a marker of physiological stress. Relationships were assessed between heart rate and the above variables using univariate and multiple regression analyses. We reported a mean resting heart rate of 74 beats/min in the cohort (mean age 45 years). On multiple regression analysis, higher heart rate was found to be independently associated with Aboriginal ethnicity, being a current smoker, having only primary level schooling, higher HbA1c and higher diastolic blood pressure (model R(2) 0.25). Elevated resting heart rate was associated with lower socioeconomic status and poorer health profile in Aboriginal and Torres Strait Islander Australians. Higher resting heart rate may be an indicator of stress and disadvantage in this population at high risk of chronic diseases.

New atomization nozzle for spray drying

NARCIS (Netherlands)

Deventer, H.C. van; Houben, R.J.; Koldeweij, R.B.J.

2013-01-01

A new atomization nozzle based on ink jet technology is introduced for spray drying. Application areas are the food and dairy industry, in the first instance, because in these industries the quality demands on the final powders are high with respect to heat load, powder shape, and size distribution.

Compton scattering and electron-atom scattering in an elliptically polarized laser field of relativistic radiation power

International Nuclear Information System (INIS)

Panek, P.; Kaminski, J.Z.; Ehlotzky, F.

2003-01-01

Presently available laser sources can yield powers for which the ponderomotive energy of an electron U p can be equal to or even larger than the rest energy mc 2 of an electron. Therefore it has become of interest to consider fundamental radiation-induced or assisted processes in such powerful laser fields. In the present work we consider laser-induced Compton scattering and laser-assisted electron atom scattering in such fields, assuming that the laser beam has arbitrary elliptic polarization. We investigate in detail the angular and polarisation dependence of the differential cross-sections of the two laser-induced or laser-assisted nonlinear processes as a function of the order N of absorbed or emitted laser photons ω. The present work is a generalization of our previous analysis of Compton scattering and electron-atom scattering in a linearly polarized laser field. (authors)

Compilation and evaluation of atomic and molecular data relevant to controlled thermonuclear research needs: USA programs

International Nuclear Information System (INIS)

Barnett, C.F.

1976-01-01

The U.S. role in the compilation and evaluation of atomic data for controlled thermonuclear research is discussed in the following three areas: (1) atomic structure data, (2) atomic collision data, and (3) surface data

Correlation of BOLD Signal with Linear and Nonlinear Patterns of EEG in Resting State EEG-Informed fMRI

Directory of Open Access Journals (Sweden)

Galina V. Portnova

2018-01-01

Full Text Available Concurrent EEG and fMRI acquisitions in resting state showed a correlation between EEG power in various bands and spontaneous BOLD fluctuations. However, there is a lack of data on how changes in the complexity of brain dynamics derived from EEG reflect variations in the BOLD signal. The purpose of our study was to correlate both spectral patterns, as linear features of EEG rhythms, and nonlinear EEG dynamic complexity with neuronal activity obtained by fMRI. We examined the relationships between EEG patterns and brain activation obtained by simultaneous EEG-fMRI during the resting state condition in 25 healthy right-handed adult volunteers. Using EEG-derived regressors, we demonstrated a substantial correlation of BOLD signal changes with linear and nonlinear features of EEG. We found the most significant positive correlation of fMRI signal with delta spectral power. Beta and alpha spectral features had no reliable effect on BOLD fluctuation. However, dynamic changes of alpha peak frequency exhibited a significant association with BOLD signal increase in right-hemisphere areas. Additionally, EEG dynamic complexity as measured by the HFD of the 2–20 Hz EEG frequency range significantly correlated with the activation of cortical and subcortical limbic system areas. Our results indicate that both spectral features of EEG frequency bands and nonlinear dynamic properties of spontaneous EEG are strongly associated with fluctuations of the BOLD signal during the resting state condition.

The Classic: On Rest and Pain: Lecture XIV.

Science.gov (United States)

Hilton, John

2009-09-01

This Classic article is a reprint of the original work by John Hilton, On Rest and Pain: Lecture XIV. An accompanying biographical sketch on John Hilton, MD, is available at DOI 10.1007/s11999-009-0927-2 . The Classic Article is reprinted with courtesy from Hilton J. On The Influence of Mechanical and Physiological Rest in the Treatment of Accidents and Surgical Diseases, and the Diagnostic Value of Pain. London, England: Bell and Daldy; 1863.

Comparison of continuously acquired resting state and extracted analogues from active tasks.

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Ganger, Sebastian; Hahn, Andreas; Küblböck, Martin; Kranz, Georg S; Spies, Marie; Vanicek, Thomas; Seiger, René; Sladky, Ronald; Windischberger, Christian; Kasper, Siegfried; Lanzenberger, Rupert

2015-10-01

Functional connectivity analysis of brain networks has become an important tool for investigation of human brain function. Although functional connectivity computations are usually based on resting-state data, the application to task-specific fMRI has received growing attention. Three major methods for extraction of resting-state data from task-related signal have been proposed (1) usage of unmanipulated task data for functional connectivity; (2) regression against task effects, subsequently using the residuals; and (3) concatenation of baseline blocks located in-between task blocks. Despite widespread application in current research, consensus on which method best resembles resting-state seems to be missing. We, therefore, evaluated these techniques in a sample of 26 healthy controls measured at 7 Tesla. In addition to continuous resting-state, two different task paradigms were assessed (emotion discrimination and right finger-tapping) and five well-described networks were analyzed (default mode, thalamus, cuneus, sensorimotor, and auditory). Investigating the similarity to continuous resting-state (Dice, Intraclass correlation coefficient (ICC), R(2) ) showed that regression against task effects yields functional connectivity networks most alike to resting-state. However, all methods exhibited significant differences when compared to continuous resting-state and similarity metrics were lower than test-retest of two resting-state scans. Omitting global signal regression did not change these findings. Visually, the networks are highly similar, but through further investigation marked differences can be found. Therefore, our data does not support referring to resting-state when extracting signals from task designs, although functional connectivity computed from task-specific data may indeed yield interesting information. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

RESTful Java patterns and best practices

CERN Document Server

Mehta, Bhakti

2014-01-01

This book is aimed at novice developers who want to gain insights into building RESTful services and improve productivity, as well as for advanced developers who want to delve into more complicated topics.

The impact of livestock on the abundance, resting behaviour and sporozoite rate of malaria vectors in southern Tanzania.

Science.gov (United States)

Mayagaya, Valeriana S; Nkwengulila, Gamba; Lyimo, Issa N; Kihonda, Japheti; Mtambala, Hassan; Ngonyani, Hassan; Russell, Tanya L; Ferguson, Heather M

2015-01-21

Increases in the coverage of long-lasting insecticidal nets (LLINs) have significantly reduced the abundance of Anopheles gambiae sensu stricto in several African settings, leaving its more zoophagic sibling species Anopheles arabiensis as the primary vector. This study investigated the impact of livestock ownership at the household level on the ecology and malaria infection rate of vectors in an area of Tanzania where An. arabiensis accounts for most malaria transmission. Mosquito vectors were collected resting inside houses, animal sheds and in outdoor resting boxes at households with and without livestock over three years in ten villages of the Kilombero Valley, Tanzania. Additionally, the abundance and sporozoite rate of vectors attempting to bite indoors at these households was assessed as an index of malaria exposure. The mean abundance of An. gambiae s.l. biting indoors was similar at houses with and without livestock. In all years but one, the relative proportion of An. arabiensis within the An. gambiae s.l. species complex was higher at households with livestock. Livestock presence had a significant impact on malaria vector feeding and resting behaviour. Anopheles arabiensis were generally found resting in cattle sheds where livestock were present, and inside houses when absent. Correspondingly, the human blood index of An. arabiensis and An. funestus s.l. was significant reduced at households with livestock, whereas that of An. gambiae s.s. was unaffected. Whilst there was some evidence that sporozoite rates within the indoor-biting An. gambiae s.l population was significantly reduced at households with livestock, the significance of this effect varied depending on how background spatial variation was accounted for. These results confirm that the presence of cattle at the household level can significantly alter the local species composition, feeding and resting behaviour of malaria vectors. However, the net impact of this livestock-associated variation in

Dissociative part-dependent resting-state activity in dissociative identity disorder: a controlled FMRI perfusion study.

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Schlumpf, Yolanda R; Reinders, Antje A T S; Nijenhuis, Ellert R S; Luechinger, Roger; van Osch, Matthias J P; Jäncke, Lutz

2014-01-01

In accordance with the Theory of Structural Dissociation of the Personality (TSDP), studies of dissociative identity disorder (DID) have documented that two prototypical dissociative subsystems of the personality, the "Emotional Part" (EP) and the "Apparently Normal Part" (ANP), have different biopsychosocial reactions to supraliminal and subliminal trauma-related cues and that these reactions cannot be mimicked by fantasy prone healthy controls nor by actors. Arterial spin labeling perfusion MRI was used to test the hypotheses that ANP and EP in DID have different perfusion patterns in response to rest instructions, and that perfusion is different in actors who were instructed to simulate ANP and EP. In a follow-up study, regional cerebral blood flow of DID patients was compared with the activation pattern of healthy non-simulating controls. Compared to EP, ANP showed elevated perfusion in bilateral thalamus. Compared to ANP, EP had increased perfusion in the dorsomedial prefrontal cortex, primary somatosensory cortex, and motor-related areas. Perfusion patterns for simulated ANP and EP were different. Fitting their reported role-play strategies, the actors activated brain structures involved in visual mental imagery and empathizing feelings. The follow-up study demonstrated elevated perfusion in the left temporal lobe in DID patients, whereas non-simulating healthy controls had increased activity in areas which mediate the mental construction of past and future episodic events. DID involves dissociative part-dependent resting-state differences. Compared to ANP, EP activated brain structures involved in self-referencing and sensorimotor actions more. Actors had different perfusion patterns compared to genuine ANP and EP. Comparisons of neural activity for individuals with DID and non-DID simulating controls suggest that the resting-state features of ANP and EP in DID are not due to imagination. The findings are consistent with TSDP and inconsistent with the idea

Dissociative part-dependent resting-state activity in dissociative identity disorder: a controlled FMRI perfusion study.

Directory of Open Access Journals (Sweden)

Yolanda R Schlumpf

Full Text Available In accordance with the Theory of Structural Dissociation of the Personality (TSDP, studies of dissociative identity disorder (DID have documented that two prototypical dissociative subsystems of the personality, the "Emotional Part" (EP and the "Apparently Normal Part" (ANP, have different biopsychosocial reactions to supraliminal and subliminal trauma-related cues and that these reactions cannot be mimicked by fantasy prone healthy controls nor by actors.Arterial spin labeling perfusion MRI was used to test the hypotheses that ANP and EP in DID have different perfusion patterns in response to rest instructions, and that perfusion is different in actors who were instructed to simulate ANP and EP. In a follow-up study, regional cerebral blood flow of DID patients was compared with the activation pattern of healthy non-simulating controls.Compared to EP, ANP showed elevated perfusion in bilateral thalamus. Compared to ANP, EP had increased perfusion in the dorsomedial prefrontal cortex, primary somatosensory cortex, and motor-related areas. Perfusion patterns for simulated ANP and EP were different. Fitting their reported role-play strategies, the actors activated brain structures involved in visual mental imagery and empathizing feelings. The follow-up study demonstrated elevated perfusion in the left temporal lobe in DID patients, whereas non-simulating healthy controls had increased activity in areas which mediate the mental construction of past and future episodic events.DID involves dissociative part-dependent resting-state differences. Compared to ANP, EP activated brain structures involved in self-referencing and sensorimotor actions more. Actors had different perfusion patterns compared to genuine ANP and EP. Comparisons of neural activity for individuals with DID and non-DID simulating controls suggest that the resting-state features of ANP and EP in DID are not due to imagination. The findings are consistent with TSDP and inconsistent

Sub-Angstrom Atomic-Resolution Imaging of Heavy Atoms to Light Atoms

Energy Technology Data Exchange (ETDEWEB)

O' Keefe, Michael A.; Shao-Horn, Yang

2003-05-23

Three decades ago John Cowley and his group at ASU achieved high-resolution electron microscope images showing the crystal unit cell contents at better than 4Angstrom resolution. Over the years, this achievement has inspired improvements in resolution that have enabled researchers to pinpoint the positions of heavy atom columns within the cell. More recently, this ability has been extended to light atoms as resolution has improved. Sub-Angstrom resolution has enabled researchers to image the columns of light atoms (carbon, oxygen and nitrogen) that are present in many complex structures. By using sub-Angstrom focal-series reconstruction of the specimen exit surface wave to image columns of cobalt, oxygen, and lithium atoms in a transition metal oxide structure commonly used as positive electrodes in lithium rechargeable batteries, we show that the range of detectable light atoms extends to lithium. HRTEM at sub-Angstrom resolution will provide the essential role of experimental verification for the emergent nanotech revolution. Our results foreshadow those to be expected from next-generation TEMs with Cs-corrected lenses and monochromated electron beams.

Lattice location of diffused Zn atoms in GaAs and InP single crystals

International Nuclear Information System (INIS)

Chan, L.Y.; Yu, K.M.; Ben-Tzur, M.; Haller, E.E.; Jaklevic, J.M.; Walukiewicz, W.; Hanson, C.M.

1991-01-01

We have investigated the saturation phenomenon of the free carrier concentration in p-type GaAs and InP single crystals doped by zinc diffusion. The free hole saturation occurs at 10 20 cm -3 for GaAs, but the maximum concentration for InP appears at mid 10 18 cm -3 . The difference in the saturation hole concentrations for these materials is investigated by studying the incorporation and the lattice location of the impurity zinc, an acceptor when located on a group III atom site. Zinc is diffused into the III-V wafers in a sealed quartz ampoule. Particle-induced x-ray emission with ion-channeling techniques are employed to determine the exact lattice location of the zinc atoms. We have found that over 90% of all zinc atoms occupy Ga sites in the diffused GaAs samples, while for the InP case, the zinc substitutionality is dependent on the cooling rate of the sample after high-temperature diffusion. For the slowly cooled sample, a large fraction (∼90%) of the zinc atoms form random precipitates of Zn 3 P 2 and elemental Zn. However, when rapidly cooled only 60% of the zinc forms such precipitates while the rest occupies specific sites in the InP. We analyze our results in terms of the amphoteric native defect model. We show that the difference in the electrical activity of the Zn atoms in GaAs and InP is a consequence of the different location of the Fermi level stabilization energy in these two materials

Atomic absorption spectrometry using tungsten and molybdenum tubes as metal atomizer

International Nuclear Information System (INIS)

Kaneco, Satoshi; Katsumata, Hideyuki; Ohta, Kiyohisa; Suzuki, Tohru

2007-01-01

We have developed a metal tube atomizer for the electrothermal atomization atomic absorption spectrometry (ETA-AAS). Tungsten, molybdenum, platinum tube atomizers were used as the metal atomizer for ETA-AAS. The atomization characteristics of various metals using these metal tube atomizers were investigated. The effects of heating rate of atomizer, atomization temperature, pyrolysis temperature, argon purge gas flow rate and hydrogen addition on the atomic absorption signal were investigated for the evaluation of atomization characteristics. Moreover, ETA-AAS with metal tube atomizer has been combined with the slurry-sampling techniques. Ultrasonic slurry-sampling ETA-AAS with metal tube atomizer were effective for the determination of trace metal elements in biological materials, calcium drug samples, herbal medicine samples, vegetable samples and fish samples. Furthermore, a preconcentration method of trace metals involving adsorption on a metal wire has been applied to ETA-AAS with metal tube atomizer. (author)

Information Flow Between Resting-State Networks.

Science.gov (United States)

Diez, Ibai; Erramuzpe, Asier; Escudero, Iñaki; Mateos, Beatriz; Cabrera, Alberto; Marinazzo, Daniele; Sanz-Arigita, Ernesto J; Stramaglia, Sebastiano; Cortes Diaz, Jesus M

2015-11-01

The resting brain dynamics self-organize into a finite number of correlated patterns known as resting-state networks (RSNs). It is well known that techniques such as independent component analysis can separate the brain activity at rest to provide such RSNs, but the specific pattern of interaction between RSNs is not yet fully understood. To this aim, we propose here a novel method to compute the information flow (IF) between different RSNs from resting-state magnetic resonance imaging. After hemodynamic response function blind deconvolution of all voxel signals, and under the hypothesis that RSNs define regions of interest, our method first uses principal component analysis to reduce dimensionality in each RSN to next compute IF (estimated here in terms of transfer entropy) between the different RSNs by systematically increasing k (the number of principal components used in the calculation). When k=1, this method is equivalent to computing IF using the average of all voxel activities in each RSN. For k≥1, our method calculates the k multivariate IF between the different RSNs. We find that the average IF among RSNs is dimension dependent, increasing from k=1 (i.e., the average voxel activity) up to a maximum occurring at k=5 and to finally decay to zero for k≥10. This suggests that a small number of components (close to five) is sufficient to describe the IF pattern between RSNs. Our method--addressing differences in IF between RSNs for any generic data--can be used for group comparison in health or disease. To illustrate this, we have calculated the inter-RSN IF in a data set of Alzheimer's disease (AD) to find that the most significant differences between AD and controls occurred for k=2, in addition to AD showing increased IF w.r.t. The spatial localization of the k=2 component, within RSNs, allows the characterization of IF differences between AD and controls.

Regional homogeneity of the resting-state brain activity correlates with individual intelligence.

Science.gov (United States)

Wang, Leiqiong; Song, Ming; Jiang, Tianzi; Zhang, Yunting; Yu, Chunshui

2011-01-25

Resting-state functional magnetic resonance imaging has confirmed that the strengths of the long distance functional connectivity between different brain areas are correlated with individual differences in intelligence. However, the association between the local connectivity within a specific brain region and intelligence during rest remains largely unknown. The aim of this study is to investigate the relationship between local connectivity and intelligence. Fifty-nine right-handed healthy adults participated in the study. The regional homogeneity (ReHo) was used to assess the strength of local connectivity. The associations between ReHo and full-scale intelligence quotient (FSIQ) scores were studied in a voxel-wise manner using partial correlation analysis controlling for age and sex. We found that the FSIQ scores were positively correlated with the ReHo values of the bilateral inferior parietal lobules, middle frontal, parahippocampal and inferior temporal gyri, the right thalamus, superior frontal and fusiform gyri, and the left superior parietal lobule. The main findings are consistent with the parieto-frontal integration theory (P-FIT) of intelligence, supporting the view that general intelligence involves multiple brain regions throughout the brain. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

The situation of Chinese atomic energy and cooperation

International Nuclear Information System (INIS)

Nagasaki, Takao

2003-01-01

China will have 8.7 million kW atomic energy in 2005. Japan will complete with China in a sale war of international atomic energy and domestic power source. The position, development and situation of Chinese atomic energy and the future nuclear fuel cycle are reported. 5.4 million kW of 7 atomic power plants in China and 45.9 million kW of 53 plants in Japan are running. 3.3 million kW of 4 plants in China and 4 million kW of 4 plants in Japan are building. New type reactor, the fast breeder and high temperature gas-cooled reactor are developing. Radiation exposure to food, radiation therapy, Radio-pharmaceuticals, polymerization and treatment of sewage and smoke are carried out. The situation of atomic energy co-operation between China and Japan and other countries are stated. Japan has to change to advance mutual interests type co-operation with China. Construction of the nuclear community in Asia area and development of the international long big project are proposed. (S.Y.)

Relation of visual creative imagery manipulation to resting-state brain oscillations.

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Cai, Yuxuan; Zhang, Delong; Liang, Bishan; Wang, Zengjian; Li, Junchao; Gao, Zhenni; Gao, Mengxia; Chang, Song; Jiao, Bingqing; Huang, Ruiwang; Liu, Ming

2018-02-01

Visual creative imagery (VCI) manipulation is the key component of visual creativity; however, it remains largely unclear how it occurs in the brain. The present study investigated the brain neural response to VCI manipulation and its relation to intrinsic brain activity. We collected functional magnetic resonance imaging (fMRI) datasets related to a VCI task and a control task as well as pre- and post-task resting states in sequential sessions. A general linear model (GLM) was subsequently used to assess the specific activation of the VCI task compared with the control task. The changes in brain oscillation amplitudes across the pre-, on-, and post-task states were measured to investigate the modulation of the VCI task. Furthermore, we applied a Granger causal analysis (GCA) to demonstrate the dynamic neural interactions that underlie the modulation effect. We determined that the VCI task specifically activated the left inferior frontal gyrus pars triangularis (IFGtriang) and the right superior frontal gyrus (SFG), as well as the temporoparietal areas, including the left inferior temporal gyrus, right precuneus, and bilateral superior parietal gyrus. Furthermore, the VCI task modulated the intrinsic brain activity of the right IFGtriang (0.01-0.08 Hz) and the left caudate nucleus (0.2-0.25 Hz). Importantly, an inhibitory effect (negative) may exist from the left SFG to the right IFGtriang in the on-VCI task state, in the frequency of 0.01-0.08 Hz, whereas this effect shifted to an excitatory effect (positive) in the subsequent post-task resting state. Taken together, the present findings provide experimental evidence for the existence of a common mechanism that governs the brain activity of many regions at resting state and whose neural activity may engage during the VCI manipulation task, which may facilitate an understanding of the neural substrate of visual creativity.

Resting-state abnormalities in amnestic mild cognitive impairment: a meta-analysis.

Science.gov (United States)

Lau, W K W; Leung, M-K; Lee, T M C; Law, A C K

2016-04-26

Amnestic mild cognitive impairment (aMCI) is a prodromal stage of Alzheimer's disease (AD). As no effective drug can cure AD, early diagnosis and intervention for aMCI are urgently needed. The standard diagnostic procedure for aMCI primarily relies on subjective neuropsychological examinations that require the judgment of experienced clinicians. The development of other objective and reliable aMCI markers, such as neural markers, is therefore required. Previous neuroimaging findings revealed various abnormalities in resting-state activity in MCI patients, but the findings have been inconsistent. The current study provides an updated activation likelihood estimation meta-analysis of resting-state functional magnetic resonance imaging (fMRI) data on aMCI. The authors searched on the MEDLINE/PubMed databases for whole-brain resting-state fMRI studies on aMCI published until March 2015. We included 21 whole-brain resting-state fMRI studies that reported a total of 156 distinct foci. Significant regional resting-state differences were consistently found in aMCI patients relative to controls, including the posterior cingulate cortex, right angular gyrus, right parahippocampal gyrus, left fusiform gyrus, left supramarginal gyrus and bilateral middle temporal gyri. Our findings support that abnormalities in resting-state activities of these regions may serve as neuroimaging markers for aMCI.