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21.
Marta?BianciardiEmail author Nicola?Toschi Cornelius?Eichner Jonathan?R.?Polimeni Kawin?Setsompop Emery?N.?Brown Matti?S.?H?m?l?inen Bruce?R.?Rosen Lawrence?L.?Wald 《Magma (New York, N.Y.)》2016,29(3):451-462
Objective
Our aim was to map the in vivo human functional connectivity of several brainstem nuclei with the rest of the brain by using seed-based correlation of ultra-high magnetic field functional magnetic resonance imaging (fMRI) data.Materials and methods
We used the recently developed template of 11 brainstem nuclei derived from multi-contrast structural MRI at 7 Tesla as seed regions to determine their connectivity to the rest of the brain. To achieve this, we used the increased contrast-to-noise ratio of 7-Tesla fMRI compared with 3 Tesla and time-efficient simultaneous multi-slice imaging to cover the brain with high spatial resolution (1.1-mm isotropic nominal resolution) while maintaining a short repetition time (2.5 s).Results
The delineated Pearson’s correlation-based functional connectivity diagrams (connectomes) of 11 brainstem nuclei of the ascending arousal, motor, and autonomic systems from 12 controls are presented and discussed in the context of existing histology and animal work.Conclusion
Considering that the investigated brainstem nuclei play a crucial role in several vital functions, the delineated preliminary connectomes might prove useful for future in vivo research and clinical studies of human brainstem function and pathology, including disorders of consciousness, sleep disorders, autonomic disorders, Parkinson’s disease, and other motor disorders.22.
Mahoney Annette; Pargament Kenneth I.; Jewell Tracey; Swank Aaron B.; Scott Eric; Emery Erin; Rye Mark 《Canadian Metallurgical Quarterly》1999,13(3):321
Ninety-seven couples completed questionnaires about their involvement in joint religious activities and their perceptions regarding the sanctification of marriage, including perceived sacred qualities of marriage and beliefs about the manifestation of God in marriage. In contrast to individual religiousness and religious homogamy (distal religious constructs), these proximal religious variables directly reflect an integration of religion and marriage, and they were associated with greater global marital adjustment, more perceived benefits from marriage, less marital conflict, more verbal collaboration, and less use of verbal aggression and stalemate to discuss disagreements for both wives and husbands. The proximal measures also added substantial unique variance (adjusted R2 change ranged from .06 to .48) to specific aspects of marital functioning after controlling demographic factors and distal religious variables in hierarchical regression analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
We review a series of experiments that have established that super-oxygenated La2−x
Sr
x
CuO4+y
phase-separates at low temperature into large magnetic and superconducting regions, driven by the physics of the doped holes
themselves. Magnetization studies of trapped flux indicate that the large phase-separated magnetic and superconducting regions
develop from nanoscale regions of charge inhomogeneity present in Sr-doped La2CuO4 and other more commonly studied cuprates. Neutron studies of the elastic magnetic diffraction show that the peak intensity
grows with applied field as in La2−x
Sr
x
CuO4. However, the magnitude of the increase varies widely and is not well accounted for by current theory. 相似文献
24.
Mediation is a growing alternative to the adversarial settlement of divorce disputes that is part of a broader movement toward the private ordering of divorce. Problems with the indeterminant "best interests" standard and evidence from psychological research make mediation particularly appealing for settling child-custody disputes. Although some encouraging evidence is available on diversion of disputes from courts and consumer satisfaction with mediation, there is a considerable need for further research. Moreover, a number of practical, legal, and ethical questions about mediation remain unanswered. Psychologists can play a vital role in systematically evaluating divorce mediation and in shaping policy in regard to its practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
26.
Samuel B. Emery Keith B. Rider C. Michael Lindsay 《Propellants, Explosives, Pyrotechnics》2014,39(2):161-165
The production of stable, pre‐reactive, nanocomposite mixtures of magnesium and a perfluoropolyether (PFPE) has been achieved through the application of helium droplet cluster assembly. The nanocomposite films presented in this work demonstrated clear thermal desorption features that indicate the formation of an MgF2 passivation layer between unreacted magnesium cores and PFPE shells upon heating. Additional heating resulted in the later rupture of the MgF2 layer and release of trapped magnesium. The passivation behavior occurred only after deposition with the input of thermal energy, demonstrating the ability of helium droplets to assemble and deposit clusters in a pre‐reactive state. 相似文献
27.
Barbieri R Frank LM Nguyen DP Quirk MC Solo V Wilson MA Brown EN 《Neural computation》2004,16(2):277-307
Neural spike train decoding algorithms and techniques to compute Shannon mutual information are important methods for analyzing how neural systems represent biological signals. Decoding algorithms are also one of several strategies being used to design controls for brain-machine interfaces. Developing optimal strategies to design decoding algorithms and compute mutual information are therefore important problems in computational neuroscience. We present a general recursive filter decoding algorithm based on a point process model of individual neuron spiking activity and a linear stochastic state-space model of the biological signal. We derive from the algorithm new instantaneous estimates of the entropy, entropy rate, and the mutual information between the signal and the ensemble spiking activity. We assess the accuracy of the algorithm by computing, along with the decoding error, the true coverage probability of the approximate 0.95 confidence regions for the individual signal estimates. We illustrate the new algorithm by reanalyzing the position and ensemble neural spiking activity of CA1 hippocampal neurons from two rats foraging in an open circular environment. We compare the performance of this algorithm with a linear filter constructed by the widely used reverse correlation method. The median decoding error for Animal 1 (2) during 10 minutes of open foraging was 5.9 (5.5) cm, the median entropy was 6.9 (7.0) bits, the median information was 9.4 (9.4) bits, and the true coverage probability for 0.95 confidence regions was 0.67 (0.75) using 34 (32) neurons. These findings improve significantly on our previous results and suggest an integrated approach to dynamically reading neural codes, measuring their properties, and quantifying the accuracy with which encoded information is extracted. 相似文献
28.
V. J. Emery 《Journal of Low Temperature Physics》1970,3(5):499-507
The osmotic pressure of dilute mixtures of3He in liquid4He is calculated and compared with experiment. One parameter, which is a measure of the difference between the mean potential energy of3He atoms and4He atoms in the mixture is determined from the experiments, and good agreement is obtained with the measured values of as a function of concentration and temperature. It is shown that the osmotic pressure does not provide any accurate information about the effective interaction between3He atoms. A comparison with earlier calculations of the osmotic pressure and of the3He chemical potential is made.Work performed under the auspices of U.S. Atomic Energy Commission. 相似文献
29.
B. M. Liaw A. S. Kobayashi A. F. Emery 《International journal for numerical methods in engineering》1984,20(5):967-977
A simple dynamic finite element algorithm for analysing a propagating mixed mode crack tip is presented. A double noding technique, which can be easily incorporated into existing dynamic finite element codes, is used together with a corrected ? integral to extract modes I and II dynamic stress intensity factors of a propagating crack. The utility of the procedure is demonstrated by analysing test problems involving a mode I central crack propagating in a plate subjected to uniaxial tension, a stationary slanted central crack in a plate subjected to uniaxial inpact loading and an extending slanted-edge crack in plate subjected to uniaxial tension. 相似文献
30.
We report the case of a 26-year-old man with diffuse esophageal leiomyomatosis involving the trachea. The tumor was resected by total esophagectomy and partial resection of the trachea and the left main bronchus. The tracheobronchial defect was repaired with a free forearm skin graft with satisfactory outcome. This approach offers good long-term prospects. 相似文献