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Experimental respiratory exposure to putative Gulf War toxins promotes persistent alveolar macrophage recruitment and pulmonary inflammation.

Life Sci 2021 Jul 19:119839. Epub 2021 Jul 19.

Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA. Electronic address:

Aims: Respiratory disorders are a prominent component of Gulf War Illness. Although much of the underlying mechanisms of Gulf War Illness remain undefined, chronic immune dysfunction is a consistent feature of this multi-symptomatic, multi-organ disorder. Alveolar macrophages represent the predominant mononuclear phagocytes of the pulmonary mucosa, orchestrating the host response to pathogens and environmental stimuli. Read More

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Parotid saliva H-NMR analysis for colon cancer metabolomics: A case report.

Spec Care Dentist 2021 Jul 22. Epub 2021 Jul 22.

Dental Physical Sciences Unit, Centre for Oral Bioengineering, Institute of Dentistry, Queen Mary University of London, London, UK.

Background: A key priority in colon cancer research is the identification of molecular biomarkers to improve early diagnosis, guide prognosis, and the design of new therapeutic approaches. Saliva is a powerful diagnostic biofluid that can be used to detect systemic alterations. This study aimed to investigate the parotid saliva (PS) metabolic Proton Nuclear Magnetic Resonance ( H-NMR) profile of a patient diagnosed with colon cancer, and the subsequent changes 1 year after the end of chemotherapy. Read More

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Radiative analysis of luminescence in photoreactive systems: Application to photosensitizers for solar fuel production.

PLoS One 2021 22;16(7):e0255002. Epub 2021 Jul 22.

Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, F-63000 Clermont-Ferrand, France.

Most chemical reactions promoted by light and using a photosensitizer (a dye) are subject to the phenomenon of luminescence. Redistribution of light in all directions (isotropic luminescence emission) and in a new spectral range (luminescence emission spectrum) makes experimental and theoretical studies much more complex compared to a situation with a purely absorbing reaction volume. This has a significant impact on the engineering of photoreactors for industrial applications. Read More

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DIA-Based Proteome Profiling of Nasopharyngeal Swabs from COVID-19 Patients.

J Proteome Res 2021 Jul 22. Epub 2021 Jul 22.

Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street Southwest, Rochester, Minnesota 55905, United States.

Since the recent outbreak of COVID-19, there have been intense efforts to understand viral pathogenesis and host immune response to combat SARS-CoV-2. It has become evident that different host alterations can be identified in SARS-CoV-2 infection based on whether infected cells, animal models or clinical samples are studied. Although nasopharyngeal swabs are routinely collected for SARS-CoV-2 detection by RT-PCR testing, host alterations in the nasopharynx at the proteomic level have not been systematically investigated. Read More

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Characterization of Fe-S Clusters in Proteins by Mӧssbauer Spectroscopy.

Methods Mol Biol 2021 ;2353:281-305

Department of Biochemistry, Brandeis University, Waltham, MA, USA.

Fe Mӧssbauer spectroscopy is unparalleled in the study of Fe-S cluster-containing proteins because of its unique ability to detect all forms of iron. Enrichment of biological samples with the Fe isotope and manipulation of experimental parameters such as temperature and magnetic field allow for elucidation of the number of Fe-S clusters present in a given protein, their nuclearity, oxidation state, geometry, and ligation environment, as well as any transient states relevant to enzyme chemistry. This chapter is arranged in five sections to help navigate an experimentalist to utilize Fe Mӧssbauer spectroscopy for delineating the role and structure of biological Fe-S clusters. Read More

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January 2021

Spectral and cross-spectral analysis-A tutorial for psychologists and social scientists.

Psychol Methods 2021 Jul 22. Epub 2021 Jul 22.

Department of Family Sciences.

Social scientists have become increasingly interested in using intensive longitudinal methods to study social phenomena that change over time. Many of these phenomena are expected to exhibit cycling fluctuations (e.g. Read More

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Phononic Thermal Transport along Graphene Grain Boundaries: A Hidden Vulnerability.

Adv Sci (Weinh) 2021 Jul 21:e2101624. Epub 2021 Jul 21.

Shenzhen JL Computational Science and Applied Research Institute, Shenzhen, 518131, China.

While graphene grain boundaries (GBs) are well characterized experimentally, their influence on transport properties is less understood. As revealed here, phononic thermal transport is vulnerable to GBs even when they are ultra-narrow and aligned along the temperature gradient direction. Non-equilibrium molecular dynamics simulations uncover large reductions in the phononic thermal conductivity (κ ) along linear GBs comprising periodically repeating pentagon-heptagon dislocations. Read More

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Enhancing and quantifying spatial homogeneity in monolayer WS.

Sci Rep 2021 Jul 21;11(1):14831. Epub 2021 Jul 21.

National Physical Laboratory, Hampton Road, Teddington, TW11, 0LW, UK.

Controlling the radiative properties of monolayer transition metal dichalcogenides is key to the development of atomically thin optoelectronic devices applicable to a wide range of industries. A common problem for exfoliated materials is the inherent disorder causing spatially varying nonradiative losses and therefore inhomogeneity. Here we demonstrate a five-fold reduction in the spatial inhomogeneity in monolayer WS, resulting in enhanced overall photoluminescence emission and quality of WS flakes, by using an ambient-compatible laser illumination process. Read More

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Automated detection of muscle fatigue conditions from cyclostationary based geometric features of surface electromyography signals.

Comput Methods Biomech Biomed Engin 2021 Jul 22:1-13. Epub 2021 Jul 22.

Non-Invasive Imaging and Diagnostics Laboratory, Biomedical Engineering Group, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai, India.

In this study, an attempt has been made to develop an automated muscle fatigue detection system using cyclostationary based geometric features of surface electromyography (sEMG) signals. For this purpose, signals are acquired from fifty-eight healthy volunteers under dynamic muscle fatiguing contractions. The sEMG signals are preprocessed and the epochs of signals under nonfatigue and fatigue conditions are considered for the analysis. Read More

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Biochemical Characterization, Phytotoxic Effect and Antimicrobial Activity against Some Phytopathogens of New Gemifloxacin Schiff Base Metal Complexes.

Chem Biodivers 2021 Jul 20. Epub 2021 Jul 20.

School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano 10, 85100, Potenza, Italy.

String of Fe(III), Cu(II), Zn(II) and Zr(IV) complexes were synthesized with tetradentateamino Schiff base ligand derived by condensation of ethylene diamine with gemifloxacin. The novel Schiff base (4E,4'E)-4,4'-(ethane-1,2-diyldiazanylylidene)bis{7-[(4Z)-3-(aminomethyl)-4-(methoxyimino)pyrrolidin-1-yl]-1-cyclopropyl-6-fluoro-1,4-dihydro-1,8-naphthyridine-3-carboxylic acid} (GMFX-en) and its metal complexes were identified and confirmed by elemental analyses, FT-IR, UV/VIS, H-NMR spectra, magnetic susceptibility, conductometric measurements and thermal analyses. The FT-IR spectral data showed the chelation behavior of GMFX-en toward the metal ions through oxygen of carboxylate group and nitrogen of azomethine group. Read More

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Determination of the optimal range for virtual monoenergetic images in dual-energy CT based on physical quality parameters.

Med Phys 2021 Jul 21. Epub 2021 Jul 21.

Radiation Oncology Dept, Hospital del Mar. Parc de Salut Mar, Barcelona, Spain.

Purpose: Virtual monoenergetic images (VMI) obtained from Dual-Energy Computed Tomography (DECT) with iodinated contrast are used in radiotherapy of the Head and Neck to improve the delineation of target volumes and organs at-risk (OAR). The energies used vary from 40 keV to 70 keV, but noise at low keV and the use of Single Energy CT (SECT) at low kV settings may shrink this interval. There is no guide about how to find out the optimal range where VMI have a significant improvement related to SECT images. Read More

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Impact of Face Masks on Speech Acoustics and Vocal Effort in Healthcare Professionals.

Laryngoscope 2021 Jul 21. Epub 2021 Jul 21.

Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, Cincinnati, Ohio, U.S.A.

Objectives/hypothesis: We investigated speech acoustics and self-reported vocal symptoms in mask-wearing healthcare professionals. We hypothesized that there would be an attenuation of spectral energies and increase in vocal effort during masked speech compared to unmasked speech.

Study Design: Within and between subject quasi-experimental design. Read More

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The Usefulness of Spectral Mammography in Surgical Planning of Breast Cancer Treatment-Analysis of 999 Patients with Primary Operable Breast Cancer.

Curr Oncol 2021 Jul 12;28(4):2548-2559. Epub 2021 Jul 12.

Department of Oncology and Radiotherapy, Prof. Kornel Gibiński Independent Public Central Clinical Hospital, Medical University of Silesia, 40-514 Katowice, Poland.

Contrast-enhanced spectral mammography (CESM) is a promising, digital breast imaging method for planning surgeries. The study aimed at comparing digital mammography (MG) with CESM as predictive factors in visualizing multifocal-multicentric cancers (MFMCC) before determining the surgery extent. We analyzed 999 patients after breast cancer surgery to compare MG and CESM in terms of detecting MFMCC. Read More

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Determination of organic chlorine in water AlCl derivatization and detection by high-resolution continuum source graphite furnace molecular absorption spectrometry.

Anal Methods 2021 Jul 21. Epub 2021 Jul 21.

Leibniz-Institut für Analytische Wissenschaften - ISAS - e. V., Department Berlin, Schwarzschildstr. 8, 12489 Berlin, Germany.

High-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GF-MAS) was employed for determining adsorbable organic chlorine (AOCl) in water. Organic chlorine was indirectly quantified by monitoring the molecular absorption of the transient aluminum monochloride molecule (AlCl) around a wavelength of 261.42 nm in a graphite furnace. Read More

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Feature-based molecular networking for identification of organic micropollutants including metabolites by non-target analysis applied to riverbank filtration.

Anal Bioanal Chem 2021 Jul 20. Epub 2021 Jul 20.

Institute of Geology and Palaeontology - Applied Geology, University of Münster, Corrensstraße 24, 48149, Münster, Germany.

Due to growing concern about organic micropollutants and their transformation products (TP) in surface and drinking water, reliable identification of unknowns is required. Here, we demonstrate how non-target liquid chromatography (LC)-high-resolution tandem mass spectrometry (MS/MS) and the feature-based molecular networking (FBMN) workflow provide insight into water samples from four riverbank filtration sites with different redox conditions. First, FBMN prioritized and connected drinking water relevant and seasonally dependent compounds based on a modification-aware MS/MS cosine similarity. Read More

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Risk factors for onset or progression of epiretinal membrane after cataract surgery.

Sci Rep 2021 Jul 20;11(1):14808. Epub 2021 Jul 20.

Keye Eye Center, 326 Teheran-ro, Gangnam-gu, Seoul, Republic of Korea.

While the precise diagnosis of early stage epiretinal membrane (ERM) at the time of cataract surgery and evaluation of risk factors for development or progression of ERM after cataract surgery is increasingly important, there is only limited information. In the present study, we evaluated the risk factors for onset or progression of ERM on spectral domain optical coherence tomography (SD-OCT) after cataract surgery. The univariate analysis showed that eyes with partial posterior vitreous detachment (PVD; p < 0. Read More

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Quantification of Liver Fat Content with Ultrasound: A WFUMB Position Paper.

Ultrasound Med Biol 2021 Jul 17. Epub 2021 Jul 17.

Department Allgemeine Innere Medizin (DAIM), Kliniken Hirslanden Beau Site, Salem und Permancence, Bern, Switzerland. Electronic address:

New ultrasound methods that can be used to quantitatively assess liver fat content have recently been developed. These quantitative ultrasound (QUS) methods are based on the analysis of radiofrequency echoes detected by the transducer, allowing calculation of parameters for quantifying the fat in the liver. In this position paper, after a section dedicated to the importance of quantifying liver steatosis in patients with non-alcoholic fatty liver disease and another section dedicated to the assessment of liver fat with magnetic resonance, the current clinical studies performed using QUS are summarized. Read More

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Advances in micro-CT imaging of small animals.

Authors:
D P Clark C T Badea

Phys Med 2021 Jul 17;88:175-192. Epub 2021 Jul 17.

Quantitative Imaging and Analysis Lab, Department of Radiology, Duke University Medical Center, Durham, NC 27710, United States. Electronic address: https://sites.duke.edu/qial.

Purpose: Micron-scale computed tomography (micro-CT) imaging is a ubiquitous, cost-effective, and non-invasive three-dimensional imaging modality. We review recent developments and applications of micro-CT for preclinical research.

Methods: Based on a comprehensive review of recent micro-CT literature, we summarize features of state-of-the-art hardware and ongoing challenges and promising research directions in the field. Read More

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Resting-state EEG alpha/theta power ratio discriminates early-onset Alzheimer's disease from healthy controls.

Clin Neurophysiol 2021 Jun 6;132(9):2019-2031. Epub 2021 Jun 6.

Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey; Izmir University of Economics, Faculty of Medicine, Izmir, Turkey. Electronic address:

Objectives: The present study aims to compare early-onset Alzheimer's disease (EOAD) patients with healthy controls (HC), and late-onset Alzheimer's disease (LOAD) patients using resting-state delta, theta, alpha, and beta oscillations and provide a cut-off score of alpha/theta ratio to discriminate individuals with EOAD and young HC.

Methods: Forty-seven individuals with EOAD, 51 individuals with LOAD, and demographically-matched 49 young and 51 older controls were included in the study. Spectral-power analysis using Fast-Fourier Transformation (FFT) is performed on resting-state electroencephalography (EEG) data. Read More

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Project Vienna: A Novel Precell Mass Filter for Collision/Reaction Cell MC-ICPMS/MS.

Anal Chem 2021 Jul 20. Epub 2021 Jul 20.

Thermo Fisher Scientific (Bremen) GmbH, Hanna-Kunath Str. 11, 28199 Bremen, Germany.

The last decade has seen widespread adoption of triple quadrupole-based inductively coupled plasma-tandem mass spectrometry (ICPMS/MS) technique using a collision/reaction cell in combination with a precell bandpass mass analyzer to measure isotopes otherwise masked by spectral interferences. High-precision isotope ratio analysis containing such isotopes would benefit from a similar capability on a multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) platform, but using a quadrupole-based precell mass analyzer for MC-ICPMS/MS has several limitations. To overcome these limitations, we developed a novel precell mass analyzer for MC-ICPMS/MS using sector field technology. Read More

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Tracking the Differentiation Status of Human Neural Stem Cells through Label-Free Raman Spectroscopy and Machine Learning-Based Analysis.

Anal Chem 2021 Jul 20. Epub 2021 Jul 20.

Department of Biological Engineering, Utah State University, 4105 Old Main Hill, ENGR 402, Logan, Utah 84322, United States.

The ability to noninvasively monitor stem cells' differentiation is important to stem cell studies. Raman spectroscopy is a non-harmful imaging approach that acquires the cellular biochemical signatures. Herein, we report the first use of label-free Raman spectroscopy to characterize the gradual change during the differentiation process of live human neural stem cells (NSCs) in the in vitro cultures. Read More

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Resonant Subwavelength and Nano-Scale Grating Structures for Biosensing Application: A Comparative Study.

Sensors (Basel) 2021 Jul 1;21(13). Epub 2021 Jul 1.

Department of Electrooptics and Photonics Engineering and the Ilse Katz Institute for Nanoscale Science and Technology, School of Electrical and Computer Engineering, Ben Gurion University, Beer Sheva 84105, Israel.

Resonant-based sensors are attractive optical structures due to the easy detection of shifts in the resonance location in response to variations in the analyte refractive index (RI) in comparison to non-resonant-based sensors. In particular, due to the rapid progress of nanostructures fabrication methods, the manufacturing of subwavelength and nano-scale gratings in a large area and at a low cost has become possible. A comparative study is presented involving analysis and experimental work on several subwavelength and nanograting structures, highlighting their nano-scale features' high potential in biosensing applications, namely: (i) Thin dielectric grating on top of thin metal film (TDGTMF), which can support the excitation of extended surface plasmons (ESPs), guided mode resonance, or leaky mode; (ii) reflecting grating for conventional ESP resonance (ESPR) and cavity modes (CMs) excitation; (iii) thick dielectric resonant subwavelength grating exhibiting guided mode resonance (GMR) without a waveguide layer. Read More

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ChronoRoot: High-throughput phenotyping by deep segmentation networks reveals novel temporal parameters of plant root system architecture.

Gigascience 2021 Jul;10(7)

Research Institute for Signals, Systems and Computational Intelligence (sinc(i)), CONICET, FICH, Universidad Nacional del Litoral, Ciudad Universitaria UNL, Santa Fe, Argentina.

Background: Deep learning methods have outperformed previous techniques in most computer vision tasks, including image-based plant phenotyping. However, massive data collection of root traits and the development of associated artificial intelligence approaches have been hampered by the inaccessibility of the rhizosphere. Here we present ChronoRoot, a system that combines 3D-printed open-hardware with deep segmentation networks for high temporal resolution phenotyping of plant roots in agarized medium. Read More

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Temporal correlates to monaural edge pitch in the distribution of inter-spike interval statistics in the auditory nerve.

eNeuro 2021 Jul 19. Epub 2021 Jul 19.

Laboratory of Auditory Neurophysiology, Medical School, Campus Gasthuisberg, K. U. Leuven, B-3000 Leuven, Belgium

Pitch is a perceptual attribute enabling perception of melody. There is no consensus regarding the fundamental nature of pitch and its underlying neural code. A stimulus which has received much interest in psychophysical and computational studies is noise with a sharp spectral edge. Read More

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Cation and Anion Channelrhodopsins: Sequence Motifs and Taxonomic Distribution.

mBio 2021 Jul 20:e0165621. Epub 2021 Jul 20.

Center for Membrane Biology, Department of Biochemistry & Molecular Biology, The University of Texas Health Science Center at Houston McGovern Medical School, Houston, Texas, USA.

Cation and anion channelrhodopsins (CCRs and ACRs, respectively) primarily from two algal species, Chlamydomonas reinhardtii and Guillardia theta, have become widely used as optogenetic tools to control cell membrane potential with light. We mined algal and other protist polynucleotide sequencing projects and metagenomic samples to identify 75 channelrhodopsin homologs from four channelrhodopsin families, including one revealed in dinoflagellates in this study. We carried out electrophysiological analysis of 33 natural channelrhodopsin variants from different phylogenetic lineages and 10 metagenomic homologs in search of sequence determinants of ion selectivity, photocurrent desensitization, and spectral tuning in channelrhodopsins. Read More

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Participant-specific classifier tuning increases the performance of hand movement detection from EEG in patients with Amyotrophic Lateral Sclerosis.

J Neural Eng 2021 Jul 19. Epub 2021 Jul 19.

Information Technology, University of Applied Sciences and Arts Dortmund, Sonnenstrasse 96, Dortmund, 44139, GERMANY.

Objective: Brain-computer interface (BCI) systems can be employed to provide motor and communication assistance to patients suffering from neuromuscular diseases, such as Amyotrophic Lateral sclerosis (ALS). Movement related cortical potentials (MRCPs), which are naturally generated during movement execution, can be used to implement a BCI triggered by motor attempts. Such BCI could assist impaired motor functions of ALS patients during disease progression, and facilitate the training for the generation of reliable MRCPs. Read More

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Validation of breath biomarkers for obstructive sleep apnea.

Sleep Med 2021 Jul 3;85:75-86. Epub 2021 Jul 3.

University Hospital Zurich, Department of Pulmonology, Rämistrasse 100, 8091, Zürich, Switzerland. Electronic address:

Background And Objectives: Obstructive sleep apnea (OSA) is an underdiagnosed respiratory disease with negative metabolic and cardiovascular effects. The current gold standard for diagnosing OSA is in-hospital polysomnography, a time-consuming and costly procedure, often inconvenient for the patient. Recent studies revealed evidence for the potential of breath analysis for the diagnosis of OSA based on a disease-specific metabolic pattern. Read More

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Detection of apple proliferation disease in Malus × domestica by near infrared reflectance analysis of leaves.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Jul 13;263:120178. Epub 2021 Jul 13.

Laimburg Research Centre, Laimburg 6, Pfatten (Vadena), IT-39040 Auer (Ora), South Tyrol, Italy. Electronic address:

In this study near infrared spectroscopical analysis of dried and ground leaves was performed and combined with a multivariate data analysis to distinguish 'Candidatus Phytoplasma mali' infected from non-infected apple trees (Malus × domestica). The bacterium is the causative agent of Apple Proliferation, one of the most threatening diseases in commercial apple growing regions. In a two-year study, leaves were sampled from three apple orchards, at different sampling events throughout the vegetation period. Read More

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Surface-enhanced Raman spectral analysis for comparison of PCR products of hepatitis B and hepatitis C.

Photodiagnosis Photodyn Ther 2021 Jul 16:102440. Epub 2021 Jul 16.

Department of Chemistry, University of Central Punjab, Faisalabad Campus, Faisalabad, Pakistan.

Background: Surface-enhanced Raman spectroscopy is a reliable tool for identification and differentiation of two diseases showing same symptoms, hepatitis B (HBV) and hepatitis C (HCV).

Objectives: To develop a polymerase chain reaction technique (PCR) based SERS technique for differentiation of two human pathological conditions sharing same symptoms and analysis using multivariate data analysis techniques e.g. Read More

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Spontaneous transient brain states in EEG source space in disorders of consciousness.

Neuroimage 2021 Jul 17;240:118407. Epub 2021 Jul 17.

Department of Neurology and Stroke, University of Tübingen, Hoppe-Seyler-Str. 3, Tübingen 72076, Germany; Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany. Electronic address:

Spontaneous transient states were recently identified by functional magnetic resonance imaging and magnetoencephalography in healthy subjects. They organize and coordinate neural activity in brain networks. How spontaneous transient states are altered in abnormal brain conditions is unknown. Read More

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