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https://www.readbyqxmd.com/read/27922019/nanomechanical-motion-transduction-with-a-scalable-localized-gap-plasmon-architecture
#1
Brian J Roxworthy, Vladimir A Aksyuk
Plasmonic structures couple oscillating electromagnetic fields to conduction electrons in noble metals and thereby can confine optical-frequency excitations at nanometre scales. This confinement both facilitates miniaturization of nanophotonic devices and makes their response highly sensitive to mechanical motion. Mechanically coupled plasmonic devices thus hold great promise as building blocks for next-generation reconfigurable optics and metasurfaces. However, a flexible approach for accurately batch-fabricating high-performance plasmomechanical devices is currently lacking...
December 6, 2016: Nature Communications
https://www.readbyqxmd.com/read/27918692/the-validity-and-reliability-of-an-iphone-app-for-measuring-running-mechanics
#2
Carlos Balsalobre-Fernández, Hovannes Agopyan, Jean-Benoit Morin
The purpose of this investigation was to analyze the validity of an iPhone application (Runmatic) for measuring running mechanics. To do this, 96 steps from 12 different runs at speeds ranging from 2.77-5.55 m·s-1 were recorded simultaneously with Runmatic as well as with an opto-electronic device installed on a motorized treadmill to measure the contact and aerial time of each step. Additionally, several running mechanics variables were calculated using the contact and aerial times measured and previously validated equations...
December 5, 2016: Journal of Applied Biomechanics
https://www.readbyqxmd.com/read/27915117/from-intentions-to-actions-neural-oscillations-encode-motor-processes-through-phase-amplitude-and-phase-amplitude-coupling
#3
Etienne Combrisson, Marcela Perrone-Bertolotti, Juan Lp Soto, Golnoush Alamian, Philippe Kahane, Jean-Philippe Lachaux, Aymeric Guillot, Karim Jerbi
Goal-directed motor behavior is associated with changes in patterns of rhythmic neuronal activity across widely distributed brain areas. In particular, movement initiation and execution are mediated by patterns of synchronization and desynchronization that occur concurrently across distinct frequency bands and across multiple motor cortical areas. To date, motor-related local oscillatory modulations have been predominantly examined by quantifying increases or suppressions in spectral power. However, beyond signal power, spectral properties such as phase and phase-amplitude coupling (PAC) have also been shown to carry information with regards to the oscillatory dynamics underlying motor processes...
November 30, 2016: NeuroImage
https://www.readbyqxmd.com/read/27914432/simulation-of-nonlinear-propagation-of-biomedical-ultrasound-using-pzflex-and-the-khokhlov-zabolotskaya-kuznetsov-texas-code
#4
Shan Qiao, Edward Jackson, Constantin C Coussios, Robin O Cleveland
Nonlinear acoustics plays an important role in both diagnostic and therapeutic applications of biomedical ultrasound and a number of research and commercial software packages are available. In this manuscript, predictions of two solvers available in a commercial software package, pzflex, one using the finite-element-method (FEM) and the other a pseudo-spectral method, spectralflex, are compared with measurements and the Khokhlov-Zabolotskaya-Kuznetsov (KZK) Texas code (a finite-difference time-domain algorithm)...
September 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27913322/automatic-detection-and-classification-of-high-frequency-oscillations-in-depth-eeg-signals
#5
Nisrine Jrad, Amar Kachenoura, Isabelle Merlet, Fabrice Bartolomei, Anca Nica, Arnaud Biraben, Fabrice Wendling
GOAL: Interictal High Frequency Oscillations (HFOs [30-600 Hz]) have proven to be relevant biomarkers in epilepsy. In this paper, four categories of HFOs are considered: Gamma ([30- 80 Hz]), High-Gamma ([80-120 Hz]), Ripples ([120-250 Hz]) and Fast-Ripples ([250-600 Hz]). A universal detector of the four types of HFOs is proposed. It has the advantages of i) classifying HFOs, and thus being robust to inter- and intra-subject variability; ii) rejecting artefacts, thus being specific. METHODS: Gabor atoms are tuned to cover the physiological bands...
November 29, 2016: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/27912172/brain-heart-communication-evidence-for-central-pacemaker-oscillations-with-a-dominant-frequency-at-0-1hz-in-the-cingulum
#6
Gert Pfurtscheller, Andreas R Schwerdtfeger, Annemarie Seither-Preisler, Clemens Brunner, Christoph Stefan Aigner, Joana Brito, Marciano P Carmo, Alexandre Andrade
OBJECTIVES: In the brain and heart, oscillations at about 0.1Hz are conspicuous. It is therefore worthwhile to study the interaction between intrinsic BOLD oscillations (0.1Hz) and slow oscillations in heart rate interval (RRI) signals and differentiate between their neural and vascular origin. METHODS: We studied the phase-coupling with a 3T scanner with high scanning rate between BOLD signals in 22 regions and simultaneously recorded RRI oscillations in 23 individuals in two resting states...
November 10, 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/27912169/non-harmonicity-in-high-frequency-components-of-the-intra-operative-corticogram-to-delineate-epileptogenic-tissue-during-surgery
#7
Evelien E Geertsema, Maryse A van 't Klooster, Nicole E C van Klink, Frans S S Leijten, Peter C van Rijen, Gerhard H Visser, Stiliyan N Kalitzin, Maeike Zijlmans
OBJECTIVE: We aimed to test the potential of auto-regressive model residual modulation (ARRm), an artefact-insensitive method based on non-harmonicity of the high-frequency signal, to identify epileptogenic tissue during surgery. METHODS: Intra-operative electrocorticography (ECoG) of 54 patients with refractory focal epilepsy were recorded pre- and post-resection at 2048Hz. The ARRm was calculated in one-minute epochs in which high-frequency oscillations (HFOs; fast ripples, 250-500Hz; ripples, 80-250Hz) and spikes were marked...
November 17, 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/27910953/three-millennia-of-heavy-rainfalls-in-western-mediterranean-frequency-seasonality-and-atmospheric-drivers
#8
J P Corella, B L Valero-Garcés, S M Vicente-Serrano, A Brauer, G Benito
Documenting subdecadal-scale heavy rainfall (HR) variability over several millennia can rarely be accomplished due to the paucity of high resolution, homogeneous and continuous proxy records. Here, using a unique, seasonally resolved lake record from southern Europe, we quantify temporal changes in extreme HR events for the last 2,800 years in this region and their correlation with negative phases of the Mediterranean Oscillation (MO). Notably, scarce HR dominated by a persistent positive MO mode characterizes the so-called Migration period (CE 370-670)...
December 2, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27908000/on-synchronization-in-power-grids-modelled-as-networks-of-second-order-kuramoto-oscillators
#9
J M V Grzybowski, E E N Macau, T Yoneyama
This work concerns analytical results on the role of coupling strength in the phenomenon of onset of complete frequency locking in power-grids modelled as a network of second-order Kuramoto oscillators. Those results allow estimation of the coupling strength for the onset of complete frequency locking and to assess the features of network and oscillators that favor synchronization. The analytical results are evaluated using an order parameter defined as the normalized sum of absolute values of phase deviations of the oscillators over time...
November 2016: Chaos
https://www.readbyqxmd.com/read/27903720/oscillatory-dynamics-underlying-perceptual-narrowing-of-native-phoneme-mapping-from-6-to-12-months-of-age
#10
Silvia Ortiz-Mantilla, Jarmo A Hämäläinen, Teresa Realpe-Bonilla, April A Benasich
: During the first months of life, human infants process phonemic elements from all languages similarly. However, by 12 months of age, as language-specific phonemic maps are established, infants respond preferentially to their native language. This process, known as perceptual narrowing, supports neural representation and thus efficient processing of the distinctive phonemes within the sound environment. Although oscillatory mechanisms underlying processing of native and non-native phonemic contrasts were recently delineated in 6-month-old infants, the maturational trajectory of these mechanisms remained unclear...
November 30, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/27901052/pacific-ocean-decadal-forcing-of-long-term-changes-in-the-western-pacific-subtropical-high
#11
Shinji Matsumura, Takeshi Horinouchi
The western Pacific subtropical high (WPSH) has a significant effect on droughts, heat waves, and tropical cyclone tracks over East Asia and the northwest Pacific. The WPSH has intensified during the past three decades, but its causes are not yet well understood. Here we show that the Pacific Decadal Oscillation (PDO) is responsible for the long-term changes in the WPSH through the meridional shift of the subtropical jet, based on comprehensive data analysis and model results. El Niño-Southern Oscillation (ENSO) is the leading forcing of WPSH variability over interannual timescales, whereas the PDO accounts for its low-frequency variability, resulting in it being independent of ENSO with regard to WPSH variability...
November 30, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27900823/high-frequency-mechanostimulation-of-cell-adhesion
#12
Laith F Kadem, K Grace Suana, Michelle Holz, Wei Wang, Hannes Westerhaus, Rainer Herges, Christine Selhuber-Unkel
Cell adhesion is regulated by molecularly defined protein interactions and by mechanical forces, which can activate a dynamic restructuring of adhesion sites. Previous attempts to explore the response of cell adhesion to forces have been limited to applying mechanical stimuli that involve the cytoskeleton. In contrast, we here apply a new, oscillatory type of stimulus through push-pull azobenzenes. Push-pull azobenzenes perform a high-frequency, molecular oscillation upon irradiation with visible light that has frequently been applied in polymer surface relief grating...
November 30, 2016: Angewandte Chemie
https://www.readbyqxmd.com/read/27899890/causal-role-of-thalamic-interneurons-in-brain-state-transitions-a-study-using-a-neural-mass-model-implementing-synaptic-kinetics
#13
Basabdatta Sen Bhattacharya, Thomas P Bond, Louise O'Hare, Daniel Turner, Simon J Durrant
Experimental studies on the Lateral Geniculate Nucleus (LGN) of mammals and rodents show that the inhibitory interneurons (IN) receive around 47.1% of their afferents from the retinal spiking neurons, and constitute around 20-25% of the LGN cell population. However, there is a definite gap in knowledge about the role and impact of IN on thalamocortical dynamics in both experimental and model-based research. We use a neural mass computational model of the LGN with three neural populations viz. IN, thalamocortical relay (TCR), thalamic reticular nucleus (TRN), to study the causality of IN on LGN oscillations and state-transitions...
2016: Frontiers in Computational Neuroscience
https://www.readbyqxmd.com/read/27896067/relationship-between-high-frequency-oscillations-and-spikes-in-a-case-of-temporal-lobe-epilepsy
#14
Vishwanath Sagi, M Steven Evans
OBJECTIVE: The aim of this case report was to study the relationship between high-frequency oscillations (HFOs), spikes, and seizures in a patient with temporal lobe epilepsy. INTRODUCTION: During intracranial electroencephalography (EEG), HFOs are thought to be a marker for the seizure onset zone (SOZ). High-frequency oscillations are classified into ripples with frequencies of 70-200 Hz and fast ripples with frequencies of 200-500 Hz. Although HFOs are thought to be a marker for the SOZ, their relationship to spikes has not been studied in detail, especially within the SOZ...
2016: Epilepsy & Behavior Case Reports
https://www.readbyqxmd.com/read/27889627/subthalamic-oscillations-and-phase-amplitude-coupling-are-greater-in-the-more-affected-hemisphere-in-parkinson-s-disease
#15
Lauren A Shreve, Anca Velisar, Mahsa Malekmohammadi, Mandy Miller Koop, Megan Trager, Emma J Quinn, Bruce C Hill, Zack Blumenfeld, Camilla Kilbane, Alessandra Mantovani, Jaimie M Henderson, Helen Brontë-Stewart
OBJECTIVE: Determine the incidence of resting state oscillations in alpha/beta, high frequency (HFO) bands, and their phase amplitude coupling (PAC) in a large cohort in Parkinson's disease (PD). METHODS: Intra-operative local field potentials (LFPs) from subthalamic nucleus (STN) were recorded from 100 PD subjects, data from 74 subjects were included in the analysis. RESULTS: Alpha/beta oscillations were evident in >99%, HFO in 87% and PAC in 98% of cases...
November 10, 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/27886473/lifshitz-transitions-in-the-ferromagnetic-superconductor-ucoge
#16
Gaël Bastien, Adrien Gourgout, Dai Aoki, Alexandre Pourret, Ilya Sheikin, Gabriel Seyfarth, Jacques Flouquet, Georg Knebel
We present high field magnetoresistance, Hall effect and thermopower measurements in the Ising-type ferromagnetic superconductor UCoGe. A magnetic field is applied along the easy magnetization c axis of the orthorhombic crystal. In the different experimental probes, we observed five successive anomalies at H≈4, 9, 12, 16, and 21 T. Magnetic quantum oscillations were detected both in resistivity and thermoelectric power. At most of the anomalies, significant changes of the oscillation frequencies and the effective masses have been observed, indicating successive Fermi surface instabilities induced by the strong magnetic polarization under a magnetic field...
November 11, 2016: Physical Review Letters
https://www.readbyqxmd.com/read/27883965/frequency-independent-characteristics-of-high-frequency-oscillations-in-epileptic-and-non-epileptic-regions
#17
Martin Pail, Pavel Řehulka, Jan Cimbálník, Irena Doležalová, Jan Chrastina, Milan Brázdil
OBJECTIVE: The purpose of the presented study is to determine whether there are frequency-independent high-frequency oscillation (HFO) parameters which may differ in epileptic and non-epileptic regions. METHODS: We studied 31 consecutive patients with medically intractable focal (temporal and extratemporal) epilepsies who were examined by either intracerebral or subdural electrodes. Automated detection was used to detect HFO. The characteristics (rate, amplitude, and duration) of HFO were statistically compared within three groups: the seizure onset zone (SOZ), the irritative zone (IZ), and areas outside the IZ and SOZ (nonSOZ/nonIZ)...
October 29, 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/27882804/a-comparison-of-high-frequency-chest-wall-oscillation-and-intrapulmonary-percussive-ventilation-for-airway-clearance-in-pediatric-patients-with-tracheostomy
#18
Aneela Bidiwala, Linda Volpe, Claudia Halaby, Melissa Fazzari, Christina Valsamis, Melodi Pirzada
OBJECTIVES: The aim of this study was to compare two modes of airway clearance, the intrapulmonary percussive ventilation system (IPV) to high frequency chest wall oscillation system (HFCWO) in medically complex pediatric patients with tracheostomy requiring long term care. METHODS: This was a single center, retrospective study comparing the number of respiratory illnesses, lower respiratory tract infections (LRTI), utilization of bronchodilator and systemic steroids, and respiratory illnesses requiring acute care hospitalizations...
November 24, 2016: Postgraduate Medicine
https://www.readbyqxmd.com/read/27882298/high-frequency-oscillations-and-high-frequency-functional-network-characteristics-in-the-intraoperative-electrocorticogram-in-epilepsy
#19
W J E M Zweiphenning, M A van 't Klooster, E van Diessen, N E C van Klink, G J M Huiskamp, T A Gebbink, F S S Leijten, P H Gosselaar, W M Otte, C J Stam, K P J Braun, G J M Zijlmans
OBJECTIVE: High frequency oscillations (HFOs; > 80 Hz), especially fast ripples (FRs, 250-500 Hz), are novel biomarkers for epileptogenic tissue. The pathophysiology suggests enhanced functional connectivity within FR generating tissue. Our aim was to determine the relation between brain areas showing FRs and 'baseline' functional connectivity within EEG networks, especially in the high frequency bands. METHODS: We marked FRs, ripples (80-250 Hz) and spikes in the electrocorticogram of 14 patients with refractory temporal lobe epilepsy...
2016: NeuroImage: Clinical
https://www.readbyqxmd.com/read/27881950/a-new-approach-of-modified-submerged-patch-clamp-recording-reveals-interneuronal-dynamics-during-epileptiform-oscillations
#20
Gareth Morris, Premysl Jiruska, John G R Jefferys, Andrew D Powell
Highlights Simultaneous epileptiform LFPs and single-cell activity can be recorded in the membrane chamber.Interneuron firing can be linked to epileptiform high frequency activity.Fast ripples, unique to chronic epilepsy, can be modeled in ex vivo tissue from TeNT-treated rats. Traditionally, visually-guided patch clamp in brain slices using submerged recording conditions has been required to characterize the activity of individual neurons. However, due to limited oxygen availability, submerged conditions truncate fast network oscillations including epileptiform activity...
2016: Frontiers in Neuroscience
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