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https://www.readbyqxmd.com/read/28339118/directional-local-field-potential-recordings-for-symptom-specific-optimization-of-deep-brain-stimulation
#1
Carla Fernández-García, Guglielmo Foffani, Michele Dileone, M J Catalán-Alonso, Mercedes González-Hidalgo, J A Barcía, Fernando Alonso-Frech
No abstract text is available yet for this article.
March 24, 2017: Movement Disorders: Official Journal of the Movement Disorder Society
https://www.readbyqxmd.com/read/28336901/an-optical-sensor-with-polyaniline-gold-hybrid-nanostructures-for-monitoring-ph-in-saliva
#2
Chongdai Luo, Yangyang Wang, Xuemeng Li, Xueqin Jiang, Panpan Gao, Kang Sun, Jianhua Zhou, Zhiguang Zhang, Qing Jiang
Saliva contains important personal physiological information that is related to some diseases, and it is a valuable source of biochemical information that can be collected rapidly, frequently, and without stress. In this article, we reported a new and simple localized surface plasmon resonance (LSPR) substrate composed of polyaniline (PANI)-gold hybrid nanostructures as an optical sensor for monitoring the pH of saliva samples. The overall appearance and topography of the substrates, the composition, and the wettability of the LSPR surfaces were characterized by optical and scanning electron microscope (SEM) images, infrared spectra, and contact angles measurement, respectively...
March 17, 2017: Nanomaterials
https://www.readbyqxmd.com/read/28335018/dissecting-gamma-frequency-activity-during-human-memory-processing
#3
Michal T Kucewicz, Brent M Berry, Vaclav Kremen, Benjamin H Brinkmann, Michael R Sperling, Barbara C Jobst, Robert E Gross, Bradley Lega, Sameer A Sheth, Joel M Stein, Sandthitsu R Das, Richard Gorniak, S Matthew Stead, Daniel S Rizzuto, Michael J Kahana, Gregory A Worrell
Gamma frequency activity (30-150 Hz) is induced in cognitive tasks and is thought to reflect underlying neural processes. Gamma frequency activity can be recorded directly from the human brain using intracranial electrodes implanted in patients undergoing treatment for drug-resistant epilepsy. Previous studies have independently explored narrowband oscillations in the local field potential and broadband power increases. It is not clear, however, which processes contribute to human brain gamma frequency activity, or their dynamics and roles during memory processing...
March 13, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/28334939/association-between-tau-deposition-and-antecedent-amyloid-%C3%AE-accumulation-rates-in-normal-and-early-symptomatic-individuals
#4
Duygu Tosun, Susan Landau, Paul S Aisen, Ronald C Petersen, Mark Mintun, William Jagust, Michael W Weiner
A long-term goal of our field is to determine the sequence of pathological events, which ultimately lead to cognitive decline and dementia. In this study, we first assessed the patterns of brain tau tangle accumulation (measured with the positron emission tomography tracer 18F-AV-1451) associated with well-established Alzheimer's disease factors in a cohort including cognitively healthy elderly individuals and individuals at early symptomatic stages of Alzheimer's disease. We then explored highly associated patterns of greater 18F-AV-1451 binding and increased annualized change in cortical amyloid-β plaques measured as florbetapir positron emission tomography binding antecedent to 18F-AV-1451 positron emission tomography scans, and to what extent these multimodal pattern associations explained the variance in cognitive performance and clinical outcome measures, independently and jointly...
March 17, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/28334424/frequency-and-function-in-the-basal-ganglia-the-origins-of-beta-and-gamma-band-activity
#5
Alexander Blenkinsop, Sean Anderson, Kevin Gurney
Neural oscillations in the basal ganglia are well studied yet remain poorly understood. Behavioural correlates of spectral activity are well described, yet a quantitative hypothesis linking time domain dynamics and spectral properties to basal ganglia function has been lacking. We show, for the first time, that a unified description is possible by interpreting previously ignored structure in data describing GPi responses to cortical stimulation. These data were used to expose a pair of distinctive neuronal responses to the stimulation...
March 23, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28334317/functional-brain-parcellations-of-the-infant-brain-and-the-associated-developmental-trends
#6
Feng Shi, Andrew P Salzwedel, Weili Lin, John H Gilmore, Wei Gao
Resting-state functional connectivity studies have dramatically improved our understanding of the early human brain functional development during the past decade. However, one emerging problem that could potentially impede future progresses in the field is the definition of regions of interest (ROI), since it is well known that functional connectivity estimation can be seriously contaminated by within-ROI signal heterogeneity. In this study, based on a large-scale rsfMRI data set in human infants (230 neonates, 143 1-year olds, and 107 2-year olds), we aimed to derive a set of anatomically constrained, infant-specific functional brain parcellations using functional connectivity-based clustering...
March 14, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28333627/ultrasound-image-despeckling-using-stochastic-distance-based-bm3d
#7
Cid Santos, Diego Martins, Nelson Mascarenhas
Ultrasound image despeckling is an important research field since it can improve the interpretability of one of the main categories of medical imaging. Many techniques have been tried over the years for ultrasound despeckling, and more recently, a great deal of attention has been focused on patch-based methods, such as non-local means (NLM) and block-matching collaborative filtering (BM3D). A common idea in these recent methods is the measure of distance between patches, originally proposed as the Euclidean distance, for filtering additive white Gaussian noise...
March 21, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28332484/multivariate-regression-methods-for-estimating-velocity-of-ictal-discharges-from-human-microelectrode-recordings
#8
Jyun-You Liou, Elliot Smith, Lisa Bateman, Guy McKhann, Robert Goodman, Bradley Greger, Tyler Davis, Spencer Kellis, Paul House, Catherine Schevon
OBJECTIVE: Epileptiform discharges, an electrophysiological hallmark of seizures, can propagate across cortical tissue in a manner similar to traveling waves. Recent work has focused attention on the origination and propagation patterns of these discharges, yielding important clues to their source location and mechanism of travel. However, systematic studies of methods for measuring propagation are lacking. APPROACH: We analyzed epileptiform discharges in microelectrode array recordings of human seizures...
March 23, 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/28332116/sweating-rate-and-sweat-sodium-concentration-in-athletes-a-review-of-methodology-and-intra-interindividual-variability
#9
REVIEW
Lindsay B Baker
Athletes lose water and electrolytes as a consequence of thermoregulatory sweating during exercise and it is well known that the rate and composition of sweat loss can vary considerably within and among individuals. Many scientists and practitioners conduct sweat tests to determine sweat water and electrolyte losses of athletes during practice and competition. The information gleaned from sweat testing is often used to guide personalized fluid and electrolyte replacement recommendations for athletes; however, unstandardized methodological practices and challenging field conditions can produce inconsistent/inaccurate results...
March 22, 2017: Sports Medicine
https://www.readbyqxmd.com/read/28331888/new-concept-on-an-integrated-interior-magnetic-resonance-imaging-and-medical-linear-accelerator-system-for-radiation-therapy
#10
Xun Jia, Zhen Tian, Yan Xi, Steve B Jiang, Ge Wang
Image guidance plays a critical role in radiotherapy. Currently, cone-beam computed tomography (CBCT) is routinely used in clinics for this purpose. While this modality can provide an attenuation image for therapeutic planning, low soft-tissue contrast affects the delineation of anatomical and pathological features. Efforts have recently been devoted to several MRI linear accelerator (LINAC) projects that lead to the successful combination of a full diagnostic MRI scanner with a radiotherapy machine. We present a new concept for the development of the MRI-LINAC system...
January 2017: Journal of Medical Imaging
https://www.readbyqxmd.com/read/28331816/inhibition-of-fat-cell-differentiation-in-3t3-l1-pre-adipocytes-by-all-trans-retinoic-acid-integrative-analysis-of-transcriptomic-and-phenotypic-data
#11
Katharina Stoecker, Steffen Sass, Fabian J Theis, Hans Hauner, Michael W Pfaffl
The process of adipogenesis is controlled in a highly orchestrated manner, including transcriptional and post-transcriptional events. In developing 3T3-L1 pre-adipocytes, this program can be interrupted by all-trans retinoic acid (ATRA). To examine this inhibiting impact by ATRA, we generated large-scale transcriptomic data on the microRNA and mRNA level. Non-coding RNAs such as microRNAs represent a field in RNA turnover, which is very important for understanding the regulation of mRNA gene expression. High throughput mRNA and microRNA expression profiling was performed using mRNA hybridisation microarray technology and multiplexed expression assay for microRNA quantification...
March 2017: Biomolecular Detection and Quantification
https://www.readbyqxmd.com/read/28327449/integrated-local-binary-pattern-texture-features-for-classification-of-breast-tissue-imaged-by-optical-coherence-microscopy
#12
Sunhua Wan, Hsiang-Chieh Lee, Xiaolei Huang, Ting Xu, Tao Xu, Xianxu Zeng, Zhan Zhang, Yuri Sheikine, James L Connolly, James G Fujimoto, Chao Zhou
This paper proposes a texture analysis technique that can effectively classify different types of human breast tissue imaged by Optical Coherence Microscopy (OCM). OCM is an emerging imaging modality for rapid tissue screening and has the potential to provide high resolution microscopic images that approach those of histology. OCM images, acquired without tissue staining, however, pose unique challenges to image analysis and pattern classification. We examined multiple types of texture features and found Local Binary Pattern (LBP) features to perform better in classifying tissues imaged by OCM...
March 8, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28325490/development-and-application-of-a-new-in-line-coupling-of-a-miniaturized-boronate-affinity-monolithic-column-with-capillary-zone-electrophoresis-for-the-selective-enrichment-and-analysis-of-cis-diol-containing-compounds
#13
Maria Betzabeth Espina-Benitez, Jérôme Randon, Claire Demesmay, Vincent Dugas
An integrated, miniaturized and fully automated system was developed for the analysis (preconcentration/purification, separation and detection) of cis-diol containing molecules in complex matrices. This innovative in-line coupling system was achieved via the in-situ and localized synthesis of a short segment of silica-based monolith at the inlet of a 75-μm inner diameter fused silica capillary. The monolithic segment was locally functionalized with an acrylamide derivative of phenylboronic acid by free radical photopolymerization within 10min of irradiation time...
March 9, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28324983/the-precuneus-may-encode-irrationality-in-human-gambling
#14
P Sacre, M S D Kerr, S Subramanian, K Kahn, J Gonzalez-Martinez, M A Johnson, S V Sarma, J T Gale
Humans often make irrational decisions, especially psychiatric patients who have dysfunctional cognitive and emotional circuitry. Understanding the neural basis of decision-making is therefore essential towards patient management, yet current studies suffer from several limitations. Functional magnetic resonance imaging (fMRI) studies in humans have dominated decision-making neuroscience, but have poor temporal resolution and the blood oxygenation level-dependent signal is only a proxy for neural activity. On the other hand, lesion studies in humans used to infer functionality in decision-making lack characterization of neural activity altogether...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324965/high-dielectric-material-in-mri-numerical-assessment-of-the-reduction-of-the-induced-local-power-on-implanted-cardiac-leads
#15
Eugenio Mattei, Elena Lucano, Federica Censi, Leonardo M Angelone, Giovanni Calcagnini
High dielectric materials (HDM) have been proposed in magnetic resonance imaging (MRI) to increase the signal-to-noise ratio (SNR) of the images acquired while reducing the radiofrequency (RF) absorption in tissue. The aim of this study is to assess the potential merit of using HDM to reduce power induced at the tip of an endocardial lead in patients undergoing MRI. Numerical simulations were performed using a commercial finite-differences time-domain (FDTD) software to model the RF field generated by a birdcage body coil at 64 MHz on a human body model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324940/use-of-local-field-potentials-of-dissociated-cultures-grown-on-multi-electrode-arrays-for-pharmacological-assays
#16
G D C Mendis, E Morrisroe, C A Reid, S K Halgamuge, S Petrou
In vitro Multi-Electrode Arrays (MEA) are an extracellular recording technology that enables the analysis of networks of neurons in vitro. Neurons in culture exhibit a range of behavioral dynamics, which can be measured in terms of individual action potentials, network-wide synchronized firing and a host of other features that characterize network activity. MEA data analysis was historically focused on high frequency spike data forgoing the low frequency content of the signal. In this study, we use local field potentials, which are low frequency components of MEA signals, to differentiate between two types of antiepileptic drugs (p<;0...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324930/rtms-enhanced-gamma-oscillation-through-strengthened-network-connection
#17
Mengmeng Dou, Xin Tian
Gamma oscillations emerge generally in working memory to aspect of higher cognitive functions, and typically with the interaction of brain network. How is gamma oscillatory activity influenced by the functional connection in the brain'a network? How can gamma oscillations be increased by neural modulation to result in potential benefits for working memory? The present study aims to investigate the intensity of gamma oscillations modulated by low frequency repetitive transcranial magnetic stimulation (rTMS), and the possible brain network mechanism of increased gamma oscillations during working memory task in rats...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28323430/dual-scattering-near-field-microscope-for-correlative-nanoimaging-of-sers-and-electromagnetic-hotspots
#18
Patryk Kusch, Stefan Mastel, Niclas Sven Mueller, Nieves Morquillas, Sebastian Heeg, Roman Gorbachev, Fredrik Schedin, Uwe Huebner, Jose Ignacio Pascual, Stephanie Reich, Rainer Hillenbrand
Surface-enhanced Raman spectroscopy (SERS) enables sensitive chemical studies and materials identification, relying on electromagnetic (EM) and chemical-enhancement mechanisms. Here we introduce a tool for the correlative nanoimaging of EM and SERS hotspots - areas of strongly enhanced EM fields and Raman scattering, respectively. To that end, we implemented a grating spectrometer into a scattering-type scanning near-field optical microscope (s-SNOM) for mapping of both the elastically and inelastically (Raman) scattered light from the near-field probe - a sharp silicon tip...
March 21, 2017: Nano Letters
https://www.readbyqxmd.com/read/28319710/glacial-lake-inventory-and-lake-outburst-potential-in-uzbekistan
#19
Maxim A Petrov, Timur Y Sabitov, Irina G Tomashevskaya, Gleb E Glazirin, Sergey S Chernomorets, Elena A Savernyuk, Olga V Tutubalina, Dmitriy A Petrakov, Leonid S Sokolov, Mikhail D Dokukin, Giorgos Mountrakis, Virginia Ruiz-Villanueva, Markus Stoffel
Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years...
March 16, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28319611/functional-electronic-inversion-layers-at-ferroelectric-domain-walls
#20
J A Mundy, J Schaab, Y Kumagai, A Cano, M Stengel, I P Krug, D M Gottlob, H Dog Anay, M E Holtz, R Held, Z Yan, E Bourret, C M Schneider, D G Schlom, D A Muller, R Ramesh, N A Spaldin, D Meier
Ferroelectric domain walls hold great promise as functional two-dimensional materials because of their unusual electronic properties. Particularly intriguing are the so-called charged walls where a polarity mismatch causes local, diverging electrostatic potentials requiring charge compensation and hence a change in the electronic structure. These walls can exhibit significantly enhanced conductivity and serve as a circuit path. The development of all-domain-wall devices, however, also requires walls with controllable output to emulate electronic nano-components such as diodes and transistors...
March 20, 2017: Nature Materials
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