928 results match your criteria deconvolution peak

Untargeted metabolomics analysis by gas chromatography/time-of-flight mass spectrometry of human serum from methamphetamine abusers.

Addict Biol 2021 Jun 10:e13062. Epub 2021 Jun 10.

School of Food Science, State Key Laboratory of Food Science and Technology, National Engineering Research Center for Functional Foods, School of Food Science Synergetic Innovation Center of Food Safety and Nutrition, Joint International Research Laboratory on Food Safety, Jiangnan University, Wuxi, China.

Methamphetamine (METH) abuse has become a global public health problem. However, the potential mechanisms involving METH-induced metabolic disorders have thus far remained poorly understood. Metabolomics can provide a clue for the cause of apparent changes and consequently be used to investigate the METH-induced dysregulation of metabolite expression and the mechanism of metabolic disorder mechanism. Read More

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Systematic Review on Local Ancestor Inference From a Mathematical and Algorithmic Perspective.

Front Genet 2021 24;12:639877. Epub 2021 May 24.

State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China.

Genotypic data provide deep insights into the population history and medical genetics. The local ancestry inference (LAI) (also termed local ancestry deconvolution) method uses the hidden Markov model (HMM) to solve the mathematical problem of ancestry reconstruction based on genomic data. HMM is combined with other statistical models and machine learning techniques for particular genetic tasks in a series of computer tools. Read More

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White light emission and thermoluminescence studies of Dy activated Hardystonite (Ca ZnSi O ) phosphor.

Luminescence 2021 May 28. Epub 2021 May 28.

Department of Physics, Govt. V.Y.T.PG. Auto. College Durg, C.G., India.

Herein, we have reported the photoluminescent and thermoluminescent properties of Dy activated Ca ZnSi O phosphors synthesized via the solid-state method. The synthesized phosphors showed hardystonite type structure, and had micron sized particles. Fourier transform infrared spectroscopy (FTIR) showed the existence of the functional groups and confirmed the formation of phosphor and photoluminescent techniques. Read More

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Tracking white-matter brain modifications in chronic non-bothersome acoustic trauma tinnitus.

Neuroimage Clin 2021 May 8;31:102696. Epub 2021 May 8.

Univ. Grenoble Alpes, Inserm U1216, Grenoble Institut Neurosciences, 38000 Grenoble, France. Electronic address:

Subjective tinnitus is a symptom characterized by the perception of sound with no external acoustic source, most often accompanied by co-morbidities. To date, the specific role of white matter abnormalities related to tinnitus reaches no consensus in the literature. The goal of this study was to explore the structural connectivity related to tinnitus percept per se, thus focusing on a specific population presenting chronic non-bothersome tinnitus of similar etiology (noise induced) without co-morbidities. Read More

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Novel acquisition strategies for metabolomics using drift tube ion mobility-quadrupole resolved all ions time-of-flight mass spectrometry (IM-QRAI-TOFMS).

Anal Chim Acta 2021 Jun 12;1163:338508. Epub 2021 Apr 12.

Institute of Analytical Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria. Electronic address:

The focus of this work was the implementation of ion mobility (IM) and a prototype quadrupole driver within data independent acquisition (DIA) using a drift tube IM-QTOFMS aiming to improve the level of confidence in identity confirmation workflows for non-targeted metabolomics. In addition to conventional all ions (IM-AI) acquisition, quadrupole resolved all ions (IM-QRAI) acquisition allows a drift time-directed precursor ion isolation in DIA using sequential isolation of precursor ions using mass windows of up to 100 Da which can be rapidly ramped across single ion mobility transients (i.e. Read More

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Studies of thermoluminescence kinetic parameters of polymer pencil lead graphite under photon exposures.

Appl Radiat Isot 2021 Aug 5;174:109757. Epub 2021 May 5.

Department of Radiology and Medical Imaging, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, P.O. Box 422, Alkharj, 11942, Saudi Arabia.

This study analysed thermoluminescence (TL) glow curves of the polymer pencil lead graphite (PPLG) due to its potential applications in radiation dosimetry. The TL glow curves provide information on the physical parameters of the defects participating in luminescence process. The glow curves for different diameters PPLG samples were obtained with varying temperature from 50 to 300 °C, at a fixed heating rate of 10 °Cs. Read More

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Data Processing Optimization in Untargeted Metabolomics of Urine Using Voigt Lineshape Model Non-Linear Regression Analysis.

Metabolites 2021 Apr 29;11(5). Epub 2021 Apr 29.

Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, German Research Center for Environmental Health, D-85764 Neuherberg, Germany.

Nuclear magnetic resonance (NMR) spectroscopy is well-established to address questions in large-scale untargeted metabolomics. Although several approaches in data processing and analysis are available, significant issues remain. NMR spectroscopy of urine generates information-rich but complex spectra in which signals often overlap. Read More

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An Elementary Approximation of Dwell Time Algorithm for Ultra-Precision Computer-Controlled Optical Surfacing.

Micromachines (Basel) 2021 Apr 21;12(5). Epub 2021 Apr 21.

Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China.

The dwell time algorithm is one of the key technologies that determines the accuracy of a workpiece in the field of ultra-precision computer-controlled optical surfacing. Existing algorithms mainly consider meticulous mathematics theory and high convergence rates, making the computation process more uneven, and the flatness cannot be further improved. In this paper, a reasonable elementary approximation algorithm of dwell time is proposed on the basis of the theoretical requirement of a removal function in the subaperture polishing and single-peak rotational symmetry character of its practical distribution. Read More

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Time-dependent surface modification of uranium oxides exposed to water plasma.

Dalton Trans 2021 Apr 19;50(14):4796-4804. Epub 2021 Mar 19.

School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Department of Chemistry, Applied Physical Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.

Thin UO films exposed to water plasma under UHV conditions have been shown to be interesting models for radiation induced oxidative dissolution of spent nuclear fuel. This is partly attributed to the fact that several of the reactive oxidizing and reducing species in a water plasma are also identified as products of radiolysis of water. Exposure of UO films to water plasma has previously been shown to lead to oxidation from U(iv) to U(v) and (vi). Read More

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Spotting isomer mixtures in forensic illicit drug casework with GC-VUV using automated coelution detection and spectral deconvolution.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Mar 29;1173:122675. Epub 2021 Mar 29.

Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, PO Box 94157, Amsterdam 1090 GD, the Netherlands; Co van Ledden Hulsebosch Center (CLHC), Amsterdam Center for Forensic Science and Medicine, PO Box 94157, Amsterdam 1090 GD, the Netherlands.

Analysis of isomeric mixtures is a significant analytical challenge. In the forensic field, for example, over 1000 new psychoactive substances (NPSs), comprising of many closely related and often isomeric varieties, entered the drugs-of-abuse market within the last decade. Unambiguous identification of the isomeric form requires advanced spectroscopic techniques, such as GC-Vacuum Ultraviolet Spectroscopy (GC-VUV). Read More

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Separation of Chromatographic Co-Eluted Compounds by Clustering and by Functional Data Analysis.

Metabolites 2021 Mar 31;11(4). Epub 2021 Mar 31.

Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479 Poznań, Poland.

Peak overlapping is a common problem in chromatography, mainly in the case of complex biological mixtures, i.e., metabolites. Read More

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Study on the Overall Reaction Pathways and Structural Transformations during Decomposition of Coal Fly Ash in the Process of Alkali-Calcination.

Materials (Basel) 2021 Mar 2;14(5). Epub 2021 Mar 2.

Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle, Southwest University of Science and Technology, Mianyang 621010, China.

In this research, phase transformation and the role of NaOH on the structure of coal fly ash (CFA) during an alkali-calcination process were identified by a combination of X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and deconvolution analysis. The variation in the different functional groups and structural parameters of the raw and post-alkali calcinated CFA were analysed by deconvolution of the FTIR results, conducted with a Gaussian approach. The results, firstly, provide a deep insight into the functional groups in CFA. Read More

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Masked Multiplexed Separations to Enhance Duty Cycle for Structures for Lossless Ion Manipulations.

Anal Chem 2021 04 2;93(14):5727-5734. Epub 2021 Apr 2.

MOBILion Systems Inc., Chadds Ford, Pennsylvania 19317, United States.

The experimental paradigm of one ion packet release per spectrum severely hinders throughput in broadband ion mobility spectrometry (IMS) systems (e.g., drift tube and traveling wave systems). Read More

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Revealing consensus gene pathways associated with respiratory functions and disrupted by PM2.5 nitrate exposure at bulk tissue and single cell resolution.

Environ Pollut 2021 Jul 19;280:116951. Epub 2021 Mar 19.

Department of Respiratory Medicine, Shanghai Tenth People's Hospital, Tongji University, Shanghai, China; College of Environmental Science and Engineering, Tongji University, Shanghai, China; Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Electronic address:

Background: Nitrate is a major pollutant component in ambient PM. It is known that chronic exposure to PM NO damages respiratory functions. We aim to explore the underlying toxicological mechanism at single cell resolution. Read More

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Dating the historical old city walls of Songkhla Thailand using thermoluminescence technique.

Heliyon 2021 Feb 23;7(2):e06166. Epub 2021 Feb 23.

Division of Physics, School of Science, Walailak University, Nakhon Si Thammarat, 80160, Thailand.

The Old Historical Wall, located in Bo Yang, Songkhla Province, Thailand, is an archaeological icon believed to have been constructed during the reign of Rama III, as indicated in the royal archives, around 1837-1840 CE. However, the recorded age is the result of unofficial documentation. The establishment was based on speculation from circumstantial evidence and local stories. Read More

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February 2021

Proof-of-concept analytical instrument for label-free optical deconvolution of protein species in a mixture.

J Chromatogr A 2021 Mar 3;1641:461968. Epub 2021 Feb 3.

Department of Biochemical Engineering, University College London, Bernard Katz Building, Gower Street, London, WC1E 6BT, UK. Electronic address:

The adoption of process analytical technologies by the biopharmaceutical industry can reduce the cost of therapeutic drugs and facilitate investigation of new bioprocesses. Control of critical process parameters to retain critical product quality attributes within strict bounds is important for ensuring a consistently high product quality, but developing the sophisticated analytical technologies required has proven to be a major challenge. Here, we demonstrate a new optical technique for continuous monitoring of protein species as they are eluted from a chromatographic column, even when they fully co-elute with other protein species, without making any assumption about or peak-fitting to the elution profile. Read More

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The theory and practice of ultrafast liquid chromatography: A tutorial.

Anal Chim Acta 2021 Mar 28;1151:238170. Epub 2020 Dec 28.

Department of Chemistry & Biochemistry, University of Texas at Arlington, TX, USA. Electronic address:

Modern high-throughput experimentation and challenging analytical problems of academic/industrial research have put the responsibility on separation scientists to develop new fast separation approaches. With the availability of high-pressure pumps, small particles with hydrolytically stable surface chemistries, reduced extra-column band broadening, and low volume detectors with fast signal processing, it is now feasible to do sub-minute to sub-second chromatography. Herein, the fundamental theoretical principles of ultrafast chromatography, along with practical solutions, are reviewed. Read More

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Thermally and optically stimulated luminescence properties of BeO dosimeter with double TL peak in the main dosimetric region.

Appl Radiat Isot 2021 Apr 9;170:109635. Epub 2021 Feb 9.

Institute of Nuclear Sciences, Ankara University, 06100, Beşevler, Ankara, Turkey.

Beryllium oxide (BeO), which has a widely known single main TL peak over the main dosimetric region, is an important luminescent material widely used in personal, medical, and environmental dosimetry fields. The thermal and optically stimulated luminescence properties (TL and OSL) of the BeO dosimeter, supplied by a private company in Turkey (BeO) that yields a double peak in the main dosimetric region (100-300 °C; heating rate = 2 °C/s) were studied. The corresponding properties were compared to the commercially prevalent Thermalox 995 BeO (BeO). Read More

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Analysis of SEC-SAXS data via EFA deconvolution and Scatter.

J Vis Exp 2021 01 28(167). Epub 2021 Jan 28.

Laboratoire de Physiologie Cellulaire and Végétale, Université Grenoble Alpes/CNRS/CEA/INRA/BIG;

BioSAXS is a popular technique used in molecular and structural biology to determine the solution structure, particle size and shape, surface-to-volume ratio and conformational changes of macromolecules and macromolecular complexes. A high quality SAXS dataset for structural modeling must be from monodisperse, homogeneous samples and this is often only reached by a combination of inline chromatography and immediate SAXS measurement. Most commonly, size-exclusion chromatography is used to separate samples and exclude contaminants and aggregations from the particle of interest allowing SAXS measurements to be made from a well-resolved chromatographic peak of a single protein species. Read More

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January 2021

Observation of Core Phonon in Electron-Phonon Coupling in Au Nanoclusters.

J Phys Chem Lett 2021 Feb 9;12(6):1690-1695. Epub 2021 Feb 9.

Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.

Temperature-dependent optical properties are of paramount importance for fundamentally understanding the electron-phonon interactions and phonon modes in atomically precise nanocluster materials. In this work, low-temperature optical absorption spectra of the icosahedral [Au(SR)] nanocluster are measured from room temperature down to liquid helium temperature by adopting a thin-film-based technique. The thin-film measurement is further compared with results from the previous solution-based method. Read More

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February 2021

NMF-Based Spectral Deconvolution with a Web Platform GC Mixture Touch.

Yasuyuki Zushi

ACS Omega 2021 Feb 19;6(4):2742-2748. Epub 2021 Jan 19.

Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaragi 305-8506, Japan.

Complete separation of chemicals in a complex mixture is far from being achieved even with the current high-performance separation technology, such as gas chromatography-mass spectrometry (GC-MS). Several deconvolution techniques based on multivariate curve resolution (MCR), or model peak methods, which are represented by AMDIS, have been developed to address the above-mentioned issue. The model peak methods have been developed to provide easy-to-use tools, including AMDIS, but are limited for MCR with approximation methods. Read More

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February 2021

Ceramic based electronic component as retrospective radiation dosimeter.

Appl Radiat Isot 2021 Apr 28;170:109618. Epub 2021 Jan 28.

Safety Quality and Resource Management Group, India; Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam, 603102, India.

Surface mount electronic devices (like resistors, capacitors, and inductors) extracted from the portable electronic devices (mobile phones, USB drives, etc.) have been studied for dose reconstruction using luminescence techniques for radiological or nuclear emergencies. In this work, carbon coated ceramic resistors removed from the electronic instruments are analyzed using thermo luminescence (TL) technique for the retrospective dose reconstruction. Read More

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Estimation of laminar BOLD activation profiles using deconvolution with a physiological point spread function.

J Neurosci Methods 2021 Apr 5;353:109095. Epub 2021 Feb 5.

Donders Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, the Netherlands; Erwin L. Hahn Institute for Magnetic Resonance Imaging, 45141, Essen, Germany. Electronic address:

Background: The specificity of gradient echo (GE)-BOLD laminar fMRI activation profiles is degraded by intracortical veins that drain blood from lower to upper cortical layers, propagating activation signal in the same direction. This work describes an approach to obtain layer specific profiles by deconvolving the measured profiles with a physiological Point Spread Function (PSF).

New Method: It is shown that the PSF can be characterised by a TE-dependent peak to tail (p2t) value that is independent of cortical depth and can be estimated by simulation. Read More

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X-ray Photoelectron Spectroscopy Analysis of Chitosan-Graphene Oxide-Based Composite Thin Films for Potential Optical Sensing Applications.

Polymers (Basel) 2021 Feb 2;13(3). Epub 2021 Feb 2.

Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.

In this study, X-ray photoelectron spectroscopy (XPS) was used to study chitosan-graphene oxide (chitosan-GO) incorporated with 4-(2-pyridylazo)resorcinol (PAR) and cadmium sulfide quantum dot (CdS QD) composite thin films for the potential optical sensing of cobalt ions (Co). From the XPS results, it was confirmed that carbon, oxygen, and nitrogen elements existed on the PAR-chitosan-GO thin film, while for CdS QD-chitosan-GO, the existence of carbon, oxygen, cadmium, nitrogen, and sulfur were confirmed. Further deconvolution of each element using the Gaussian-Lorentzian curve fitting program revealed the sub-peak component of each element and hence the corresponding functional group was identified. Read More

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February 2021

PCA denoising and Wiener deconvolution of P 3D CSI data to enhance effective SNR and improve point spread function.

Magn Reson Med 2021 06 1;85(6):2992-3009. Epub 2021 Feb 1.

Department of Radiology, Imaging Division, University Medical Center Utrecht, Utrecht, The Netherlands.

Purpose: This study evaluates the performance of 2 processing methods, that is, principal component analysis-based denoising and Wiener deconvolution, to enhance the quality of phosphorus 3D chemical shift imaging data.

Methods: Principal component analysis-based denoising increases the SNR while maintaining spectral information. Wiener deconvolution reduces the FWHM of the voxel point spread function, which is increased by Hamming filtering or Hamming-weighted acquisition. Read More

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Chemical interaction of 4-META with enamel in resin-enamel bonds.

Dent Mater J 2021 May 30;40(3):683-688. Epub 2021 Jan 30.

Division of Biomaterials and Bioengineering, School of Dentistry, Health Sciences University of Hokkaido.

X-ray photoelectron spectroscopy (XPS) is used to analyze 4-META resin and enamel that are debonded at an adhesive interface. The XPS spectra showed two chemical states for Ca: one resulted from Ca of hydroxyapatite and the other, an unknown chemical state, suggested that Ca was chemically bonded with 4-META. We postulate that for a chemical reaction of 4-META and hydroxyapatite, the chemical structure of carboxyl groups will resemble that of calcium phthalate. Read More

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Reinjection flow field-flow fractionation method for nanoparticle quantitative analysis in unknown and complex samples.

J Chromatogr A 2021 Feb 13;1638:461897. Epub 2021 Jan 13.

Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, 430078, China. Electronic address:

An analytical challenge that arises in environmental and food analysis is to quantify heterogeneous nanoparticles especially in polydisperse and complex samples. The method stated herein based on the reinjection asymmetrical flow field-flow fractionation (AF4 × AF4) coupled with inductively coupled plasma-mass spectrometer (ICP-MS) and statistical deconvolution allowed for identifying the molecular weight (Mw) and selenium abundance of the low Mw protein fractions (ca. < 132 kDa) in an unknown and complex sample (e. Read More

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February 2021

Wavelength Calibration Uncertainty in Protein Circular Dichroism Data Bank Spectra.

Appl Spectrosc 2021 Jan 28:3702821990748. Epub 2021 Jan 28.

Algorithms to objectively compare the circular dichroism spectra of biopharmaceuticals, as a measure of consistent higher order structure, are sensitive to errors in spectropolarimeter wavelength calibration. A public database, the Protein Circular Dichroism Data Bank contains 108 unique calibration spectra of -camphor-10-sulphonic acid, mainly collected on synchrotron-based instruments. Deconvolution of these spectra and statistical evaluation of the peaks located near 290 and 190 nm shows significant mean peak wavelength differences between instruments, with data ranges of 1. Read More

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January 2021

An improved time reversal mirror based on standard linear frequency modulation waveform.

Sci Rep 2021 Jan 8;11(1):194. Epub 2021 Jan 8.

State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.

Time reversal mirror (TRM) technology is the adaptive focusing method evolved from the phase conjugate method in optics. Conventional incentive method in TRM technology is a narrow pulse signal with a high bandwidth. In this paper, the autocorrelation property of the TRM was proved from the time-reversal symmetry of the wave equation. Read More

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January 2021

Characterization of chitosan with different degree of deacetylation and equal viscosity in dissolved and solid state - Insights by various complimentary methods.

Int J Biol Macromol 2021 Feb 6;171:242-261. Epub 2021 Jan 6.

Leibniz-Institut für Polymerforschung Dresden, Physikalische Chemie und Physik der Polymere, Hohe Straße 6, D-01069 Dresden, Germany. Electronic address:

In recent years, chitosan has attracted considerable interest in many fields due to its sufficient charge density under biological, non-hazardous conditions. Since chitosan originates from natural resources and has two different monomer units, its characterization must be carried out in a goal-oriented and precise manner. This work focuses on the characterization of chitosans most important parameters - solubility, crystallinity, degree of deacetylation (DD) and molecular weight - in a simple and convenient way. Read More

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February 2021