28,055 results match your criteria temporal resolution


Pitch perception is more robust to interference and better resolved when provided by pulse rate than by modulation frequency of cochlear implant stimulation.

Hear Res 2021 Jul 24;409:108319. Epub 2021 Jul 24.

Auditory Research Center, Caruso Department of Otolaryngology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States; Department of Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States.

Cochlear implants are medical devices that have been used to restore hearing to more than half a million people worldwide. Most recipients achieve high levels of speech comprehension through these devices, but speech comprehension in background noise and music appreciation in general are markedly poor compared to normal hearing. A key aspect of hearing that is notably diminished in cochlear implant outcomes is the sense of pitch provided by these devices. Read More

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Advances in vascular anatomy and pathophysiology using high resolution and multiparametric sonography.

J Vasc Access 2021 Aug 2:11297298211020150. Epub 2021 Aug 2.

Radiodiagnostic and Interventional Radiology Department, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.

B-mode and Color Doppler are the first-line imaging modalities in cardiovascular diseases. However, conventional ultrasound (US) provides a lower spatial and temporal resolution (70-100 frames per second) compared to ultrafast technology which acquires several thousand frames per second. Consequently, the multiparametric ultrafast platforms manage new imaging algorithms as high-frequency ultrasound, contrast-enhanced ultrasound, shear wave elastography, vector flow, and local pulse wave imaging. Read More

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Online monitoring of lead-214 (Pb) on atmospheric aerosols by low-resolution gamma-ray spectrometry.

Environ Monit Assess 2021 Aug 2;193(8):545. Epub 2021 Aug 2.

Marine Hydrophysical Institute of RAS, Kapitanskaya Street 2, Sevastopol, Russian Federation, 299011.

This paper provides a new approach that simplifies the monitoring of Pb activity concentration on aerosols in the atmospheric surface layer. The approach allows obtaining data on Pb activity concentration with the discreteness of 2 h. The experimental setup described in the paper made it possible to achieve a minimum detectable activity level of 0. Read More

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Using infrared geostationary remote sensing to determine particulate matter ground-level composition and concentration.

Authors:
M Sowden D Blake

Air Qual Atmos Health 2021 Jul 28:1-10. Epub 2021 Jul 28.

Centre for Ecosystem Management, School of Science, Edith Cowan University, Joondalup, WA Australia.

Speciated ground-level aerosol concentrations are required to understand and mitigate health impacts from dust storms, wildfires, and other aerosol emissions. Globally, surface monitoring is limited due to cost and infrastructure demands. While remote sensing can help estimate respirable (i. Read More

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Technical feasibility and adherence of the Remote Monitoring Application in Psychiatry (ReMAP) for the assessment of affective symptoms.

J Affect Disord 2021 Jul 16;294:652-660. Epub 2021 Jul 16.

Institute for Translational Psychiatry, University of Münster, Germany; Interdisciplinary Centre for Clinical Research (IZKF) Münster, University of Münster, Germany. Electronic address:

Background: Smartphone-based monitoring constitutes a cost-effective instrument to assess and predict affective symptom trajectories. Large-scale transdiagnostic studies utilizing this methodology are yet lacking in psychiatric research. Thus, we introduce the Remote Monitoring Application in Psychiatry (ReMAP) and evaluate its feasibility and adherence in a large transdiagnostic sample. Read More

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Illuminating Plasmodium invasion by lattice-light-sheet microscopy.

Trends Parasitol 2021 Jul 28. Epub 2021 Jul 28.

Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; German Center for Infection Research, DZIF, partner site Heidelberg, Germany. Electronic address:

Plasmodium merozoites invade erythrocytes in a stepwise manner through ligand binding, calcium signaling, and membrane deformation. Using a recently developed light-sheet microscope, Geoghegan et al. investigated invasion with unprecedented temporal resolution. Read More

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Combined medical therapy and neurosurgical revascularization preventing stroke in post-varicella angiopathy: Case report and review of literature.

Brain Dev 2021 Jul 28. Epub 2021 Jul 28.

Neurosurgery Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.

Background: Post varicella angiopathy (PVA) is an underdiagnosed but potentially severe disease in both pediatric and adult settings. No guidelines are available for the medical and neurosurgical management of this condition. We report the first pediatric case with headache and PVA who was treated with surgical revascularization before the onset of ischemic events. Read More

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Inhibitory synapse loss and accumulation of amyloid beta in inhibitory presynaptic terminals in Alzheimer's disease.

Eur J Neurol 2021 Jul 31. Epub 2021 Jul 31.

The University of Edinburgh, Centre for Discovery Brain Sciences, UK Dementia Research Institute, Edinburgh.

Background: Synapse degeneration in Alzheimer's disease (AD) correlates strongly with cognitive decline. There is well-established excitatory synapse loss in Alzheimer's disease with known contributions of pathological amyloid beta (Aβ) to excitatory synapse dysfunction and loss. Despite clear changes in circuit excitability in AD and model systems, relatively little is known about pathology in inhibitory synapses. Read More

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An in silico validation framework for quantitative DCE-MRI techniques based on a dynamic digital phantom.

Med Image Anal 2021 Jul 20;73:102186. Epub 2021 Jul 20.

Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, 201 E 24th St, Austin, TX 78712, United States; Livestrong Cancer Institutes, United States; Departments of Biomedical Engineering, United States; Departments of Diagnostic Medicine, United States; Departments of Oncology, The University of Texas at Austin, Austin, TX 78712, United States; Department of Imaging Physics, MD Anderson Cancer Center, Houston, TX 77030, United States.

Quantitative evaluation of an image processing method to perform as designed is central to both its utility and its ability to guide the data acquisition process. Unfortunately, these tasks can be quite challenging due to the difficulty of experimentally obtaining the "ground truth" data to which the output of a given processing method must be compared. One way to address this issue is via "digital phantoms", which are numerical models that provide known biophysical properties of a particular object of interest. Read More

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Estimation of surface-level NO and O concentrations using TROPOMI data and machine learning over East Asia.

Environ Pollut 2021 Jul 16;288:117711. Epub 2021 Jul 16.

Environmental Satellite Centre, Climate and Air Quality Research Department, Incheon, South Korea.

In East Asia, air quality has been recognized as an important public health problem. In particular, the surface concentrations of air pollutants are closely related to human life. This study aims to develop models for estimating high spatial resolution surface concentrations of NO and O from TROPOspheric Monitoring Instrument (TROPOMI) data in East Asia. Read More

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Stationary monitoring and source apportionment of VOCs in a chemical industrial park by combining rapid direct-inlet MSs with a GC-FID/MS.

Sci Total Environ 2021 Jun 24;795:148639. Epub 2021 Jun 24.

Shanghai Environmental Monitoring Center, State Ecologic Environmental Scientific Observation and Research Station at Dianshan Lake, Shanghai 200235, China.

Fast and comprehensive monitoring of VOCs, required for air quality management in large-scale chemical industrial parks in China, cannot be accomplished by stationary measurements using conventional GC-FID or GC-MS alone due to their low temporal resolutions and limited detectable ranges. Novel direct-inlet mass spectrometry (DI-MS) has been widely applied for real-time monitoring of VOCs. To verify its applicability in industrial settings, high mass-resolution proton-transfer-reaction time-of-flight MS (HMR-PTR-TOFMS), single-photon ionization time-of-flight MS (SPI-TOFMS), together with online GC-FID/MS were simultaneously deployed at the boundary of one of the largest chemical industrial parks in eastern China. Read More

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Temporal vision: measures, mechanisms and meaning.

Authors:
Kristian Donner

J Exp Biol 2021 Jul 30;224(15). Epub 2021 Jul 30.

Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland.

Time is largely a hidden variable in vision. It is the condition for seeing interesting things such as spatial forms and patterns, colours and movements in the external world, and yet is not meant to be noticed in itself. Temporal aspects of visual processing have received comparatively little attention in research. Read More

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High spatio-temporal resolution measurement of A R and A R interactions combined with Iem-spFRET and E-FRET methods.

J Biophotonics 2021 Jul 30:e202100172. Epub 2021 Jul 30.

MOE Key Laboratory of OptoElectronic Science and Technology for Medicine and Fujian Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou, Fujian, China.

A R-A R heterodimers regulate striatal glutamatergic neurotransmission. However, few researches about kinetics have been reported. Here, we combined Iem-spFRET and E-FRET to investigate the kinetics of A R and A R interaction. Read More

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From whole organism to ultrastructure: progress in axonal imaging for decoding circuit development.

Development 2021 Sep 30;148(18). Epub 2021 Jul 30.

Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.

Since the pioneering work of Ramón y Cajal, scientists have sought to unravel the complexities of axon development underlying neural circuit formation. Micrometer-scale axonal growth cones navigate to targets that are often centimeters away. To reach their targets, growth cones react to dynamic environmental cues that change in the order of seconds to days. Read More

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September 2021

Ultra-High Field 7-Tesla Magnetic Resonance Imaging and Electroencephalography Findings in Epilepsy.

Can Assoc Radiol J 2021 Jul 30:8465371211031802. Epub 2021 Jul 30.

Department of Medical Imaging, Schulich School of Medicine and Dentistry, 6221Western University, London, Ontario, Canada.

Purpose: Assessment of patients for temporal lobe epilepsy (TLE) surgery requires multimodality input, including EEG recordings to ensure optimal surgical planning. Often EEG demonstrates abnormal foci not detected on 1.5T MRI. Read More

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The effect of water stress on net primary productivity in northwest China.

Environ Sci Pollut Res Int 2021 Jul 29. Epub 2021 Jul 29.

School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China.

Net primary productivity (NPP) has been widely used as the indicator of vegetation function and exhibits large spatial and temporal variations caused by numerous factors. Northwest China (NWC) is one of the driest regions in China, and water supply is the key determinant of NPP here. However, studies on the effects of water stress on NPP in NWC at the regional scale are still relatively lacking. Read More

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Hierarchical geodesic modeling on the diffusion orientation distribution function for longitudinal DW-MRI analysis.

Med Image Comput Comput Assist Interv 2020 Oct 29;12267:311-321. Epub 2020 Sep 29.

Department of Computer Science and Engineering, New York University, NY, USA.

The analysis of anatomy that undergoes rapid changes, such as neuroimaging of the early developing brain, greatly benefits from spatio-temporal statistical analysis methods to represent population variations but also subject-wise characteristics over time. Methods for spatio-temporal modeling and for analysis of longitudinal shape and image data have been presented before, but, to our knowledge, not for diffusion weighted MR images (DW-MRI) fitted with higher-order diffusion models. To bridge the gap between rapidly evolving DW-MRI methods in longitudinal studies and the existing frameworks, which are often limited to the analysis of derived measures like fractional anisotropy (FA), we propose a new framework to estimate a population trajectory of longitudinal diffusion orientation distribution functions (dODFs) along with subject-specific changes by using hierarchical geodesic modeling. Read More

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October 2020

Mind the gap: State-of-the-art technologies and applications for EEG-based brain-computer interfaces.

APL Bioeng 2021 Sep 20;5(3):031507. Epub 2021 Jul 20.

Department of Bioengineering, Imperial College London, Royal School of Mines, London SW7 2AZ, United Kingdom.

Brain-computer interfaces (BCIs) provide bidirectional communication between the brain and output devices that translate user intent into function. Among the different brain imaging techniques used to operate BCIs, electroencephalography (EEG) constitutes the preferred method of choice, owing to its relative low cost, ease of use, high temporal resolution, and noninvasiveness. In recent years, significant progress in wearable technologies and computational intelligence has greatly enhanced the performance and capabilities of EEG-based BCIs (eBCIs) and propelled their migration out of the laboratory and into real-world environments. Read More

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September 2021

Noninvasive time-sorting in radio frequency-compressed ultrafast electron diffraction.

Struct Dyn 2021 Jul 23;8(4):044303. Epub 2021 Jul 23.

We demonstrate a noninvasive time-sorting method for ultrafast electron diffraction (UED) experiments with radio frequency (rf)-compressed electron beams. We show that electron beam energy and arrival time at the sample after the rf compression are strongly correlated, such that the arrival time jitter may be corrected through the measurement of the beam energy. The method requires minimal change to the infrastructure of most of the UED machines and is applicable to both keV and MeV UED. Read More

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Meningeal Hemangiopericytoma Presenting as Pure Gerstmann Syndrome: A Double Rarity.

Cureus 2021 Jun 23;13(6):e15863. Epub 2021 Jun 23.

Neuro-Oncology, University of Mississippi Medical Center, Jackson, USA.

Gerstmann syndrome is a neurobehavioral syndrome characterized by four cardinal symptoms: acalculia, agraphia, finger-toe agnosia, and dysgraphia. The syndrome is caused primarily by lesions at the confluence of parietal, temporal, and occipital lobes, but also can involve the middle frontal lobe of the dominant hemisphere. Documented inciting lesions include stroke, tumor, hemorrhage, arteriovenous malformations, and seizures. Read More

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Recording Strategies for High Channel Count, Densely Spaced Microelectrode Arrays.

Front Neurosci 2021 13;15:681085. Epub 2021 Jul 13.

Institute of Microelectronics of Seville (IMSE-Centro Nacional de Microelectrónica), Spanish National Research Council, Seville, Spain.

Neuroscience research into how complex brain functions are implemented at an extra-cellular level requires neural recording interfaces, including microelectrodes and read-out circuitry, with increased observability and spatial resolution. The trend in neural recording interfaces toward employing high-channel-count probes or 2D microelectrodes arrays with densely spaced recording sites for recording large neuronal populations makes it harder to save on resources. The low-noise, low-power requirement specifications of the analog front-end usually requires large silicon occupation, making the problem even more challenging. Read More

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Extracellular Recording of Entire Neural Networks Using a Dual-Mode Microelectrode Array With 19584 Electrodes and High SNR.

IEEE J Solid-State Circuits 2021 Aug 24;56(8):2466-2475. Epub 2021 Mar 24.

Urs Frey was with the Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland. He is now with MaxWell Biosystems AG, 8047 Zurich, Switzerland.

Electrophysiological research on neural networks and their activity focuses on the recording and analysis of large data sets that include information of thousands of neurons. CMOS microelectrode arrays (MEAs) feature thousands of electrodes at a spatial resolution on the scale of single cells and are, therefore, ideal tools to support neural-network research. Moreover, they offer high spatio-temporal resolution and signal to-noise ratio (SNR) to capture all features and subcellular resolution details of neuronal signaling. Read More

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Psychiatric outcome of temporal lobe epilepsy surgery: A prospective, 2-year follow-up study.

Epilepsy Behav 2021 Jul 26;122:108216. Epub 2021 Jul 26.

National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Shizuoka, Japan.

Objective: We performed a prospective, longitudinal, 2-year follow-up study to clarify psychiatric courses and outcomes after temporal lobe epilepsy surgery.

Methods: We assessed 141 patients (68 men, 73 women) aged 16 or older with structured interviews and psychiatric rating scales before surgery and 3 months, 1 year, and 2 years afterward.

Results: Fifty-two patients (36. Read More

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Improvement of sensitivity and specificity for laminar BOLD fMRI with double spin-echo EPI in humans at 7 T.

Neuroimage 2021 Jul 27;241:118435. Epub 2021 Jul 27.

Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, Republic of Korea; Department of Biomedical Engineering, Sungkyunkwan University, Suwon, Republic of Korea; Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea. Electronic address:

Mapping mesoscopic cortical functional units such as columns or laminae is increasingly pursued by ultra-high field (UHF) functional magnetic resonance imaging (fMRI). The most popular approach for high-resolution fMRI is currently gradient-echo (GE) blood oxygenation level-dependent (BOLD) fMRI. However, its spatial accuracy is reduced due to its sensitivity to draining vessels, including pial veins, whereas spin-echo (SE) BOLD signal is expected to have higher spatial accuracy, albeit with lower sensitivity than the GE-BOLD signal. Read More

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Recent Advances in Radio-Frequency Coil Technologies: Flexible, Wireless, and Integrated Coil Arrays.

J Magn Reson Imaging 2021 Jul 29. Epub 2021 Jul 29.

Brain Imaging and Analysis Center, Duke University, Durham, North Carolina, USA.

Radio-frequency (RF) coils are to magnetic resonance imaging (MRI) scanners what eyes are to the human body. Because of their critical importance, there have been constant innovations driving the rapid development of RF coil technologies. Over the past four decades, the breadth and depth of the RF coil technology evolution have far exceeded the space allowed for this review article. Read More

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Predictive statistical model of early cranial development.

IEEE Trans Biomed Eng 2021 Jul 29;PP. Epub 2021 Jul 29.

Objective: We present a data-driven method to build a spatiotemporal statistical shape model predictive of normal cranial growth from birth to the age of 2 years.

Methods: The model was constructed using a normative cross-sectional computed tomography image dataset of 278 subjects. First, we propose a new standard representation of the calvaria using spherical maps to establish anatomical correspondences between subjects at the cranial sutures the main areas of cranial bone expansion. Read More

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Neurotransmitter Release of Reprogrammed Cells Using Electrochemical Detection Methods.

Authors:
Andreas Heuer

Methods Mol Biol 2021 ;2352:201-226

Behavioural Neuroscience Laboratory, Department of Experimental Medical Sciences, Lund University, Lund, Sweden.

The detection of neurotransmitter release from reprogrammed human cell is an important demonstration of their functionality. Electrochemistry has the distinct advantages over alternative methods that it allows for the measuring of the analyte of interest at a high temporal resolution. This is necessary for fast events, such as neurotransmitter release and reuptake, which happen in the order of milliseconds to seconds. Read More

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January 2021

Respiratory anomalies associated with gadoxetate disodium and gadoterate meglumine: compressed sensing MRI revealing physiologic phenomena during the entire injection cycle.

Eur Radiol 2021 Jul 29. Epub 2021 Jul 29.

Department of Radiology, University Hospital Basel, Basel, Switzerland.

Objectives: The goal of this study was to investigate the precise timeline of respiratory events occurring after the administration of two gadolinium-based contrast agents, gadoxetate disodium and gadoterate meglumine.

Materials And Methods: This retrospective study examined 497 patients subject to hepatobiliary imaging using the GRASP MRI technique (TR/TE = 4/2 ms; ST = 2.5 mm; 384 × 384 mm). Read More

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Current and future perspectives for wastewater-based epidemiology as a monitoring tool for pharmaceutical use.

Sci Total Environ 2021 May 26;789:148047. Epub 2021 May 26.

Toxicological Centre, University of Antwerp, Belgium, Universiteitsplein 1, 2610 Antwerp, Belgium. Electronic address:

The medical and societal consequences of the misuse of pharmaceuticals clearly justify the need for comprehensive drug utilization research (DUR). Wastewater-based epidemiology (WBE) employs the analysis of human metabolic excretion products in wastewater to monitor consumption patterns of xenobiotics at the population level. Recently, WBE has demonstrated its potential to evaluate lifestyle factors such as illicit drug, alcohol and tobacco consumption at the population level, in near real-time and with high spatial and temporal resolution. Read More

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Reducing SAR in 7T brain fMRI by circumventing fat suppression while removing the lipid signal through a parallel acquisition approach.

Sci Rep 2021 Jul 28;11(1):15371. Epub 2021 Jul 28.

Neurobiology Department, Weizmann Institute of Science, Rehovot, Israel.

Ultra-high-field functional magnetic resonance imaging (fMRI) offers a way to new insights while increasing the spatial and temporal resolution. However, a crucial concern in 7T human MRI is the increase in power deposition, supervised through the specific absorption rate (SAR). The SAR limitation can restrict the brain coverage or the minimal repetition time of fMRI experiments. Read More

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