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Improving the Screening Analysis of Pesticide Metabolites in Human Biomonitoring by Combining High-Throughput Incubation and Automated LC-HRMS Data Processing.

Anal Chem 2021 Jun 23. Epub 2021 Jun 23.

Department of Effect-Directed Analysis, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany.

There is a current need to monitor human exposure to a large number of pesticides and other chemicals of emerging concern (CECs). This requires screening analysis with high confidence for these compounds and their metabolites in complex matrices, which is hampered by the fact that no reference standards are available for most metabolites. We address this challenge by a high-throughput workflow based on incubation of pesticides (or other CECs) with human liver S9, followed by solid-phase extraction, liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis, and automated data processing to generate a database (retention time, precursor /, and MS spectral library) for the annotation in human samples. Read More

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Design, Synthesis, and Herbicidal Activity of Novel Phenoxypyridine Derivatives Containing Natural Product Coumarin.

Pest Manag Sci 2021 Jun 23. Epub 2021 Jun 23.

Department of Chemistry, College of Arts and Sciences, Northeast Agricultural University, Harbin, 150030, China.

Background: In recent years, protoporphyrinogen oxidase (PPO, EC 1.3.3. Read More

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Effect of transient obstructive cholestasis on liver histology: a cross-sectional study.

Sao Paulo Med J 2021 Jun 11. Epub 2021 Jun 11.

MD, PhD. Adjunct Professor, Department of Surgery, Faculdade de Ciências Médicas da Universidade de Campinas (FCM-UNICAMP), Campinas (SP), Brazil.

Background: The role of transient obstructive cholestasis on liver histology remains undetermined.

Objective: To investigate whether transient cholestasis impairs liver histology.

Design And Setting: Cross-sectional study at a public university hospital (UNICAMP), Brazil. Read More

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ID-MAM: A Validated Identity and Multi-Attribute Monitoring Method for Commercial Release and Stability Testing of a Bispecific Antibody.

Anal Chem 2021 Jun 23. Epub 2021 Jun 23.

BioTherapeutics Development & Supply-Analytical Development, Janssen Research and Development, LLC, Malvern, Pennsylvania 19355, United States.

Post-translational modifications (PTMs) that impact the safety or efficacy of protein therapeutics are critical quality attributes (CQAs) that need to be controlled to ensure product quality. Peptide mapping with online mass spectrometry (MS) is a powerful tool that has been used for many years to monitor PTM CQAs during product development. However, operating peptide mapping methods with high-resolution mass spectrometers in GMP compliant, commercial quality control (QC) labs can be difficult. Read More

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Development and Validation of a LC-MS/MS Method for the Profiling of Impurities Formed during Stress Study of Antifungal Agent-Efinaconazole.

J Chromatogr Sci 2021 Jun 23. Epub 2021 Jun 23.

Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, Tamil Nadu, India.

Liquid chromatography interfaced with mass spectroscopy (LC-MS) is a sensitive and effective analytical method that combines high-resolution separation as well as specific mass detection of impurities in formulated products and as well as in active pharmaceutical ingredient (API). In this study, LC-MS/MS was used to determine impurities formed during the stability period of Efinaconazole (EFZ, a triazole antifungal agent). The method was validated for its assay parameters such as specificity, linearity, accuracy, precision and also for solution stability. Read More

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Phototransformation of an emerging cyanotoxin (Aerucyclamide A) in simulated natural waters.

Water Res 2021 Jun 7;201:117339. Epub 2021 Jun 7.

Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China. Electronic address:

Aerucyclamide A (ACA) is an emerging cyanopeptide toxin produced by cyanobacteria, and its transformation pathway has rarely been reported. In the present study, ACA was purified from cyanobacterial extracts, and photodegradation processes were investigated in dissolved organic matter (DOM) solutions. Under simulated solar irradiation, the photodegradation of ACA was dominated by OH oxidation, accounting for ~72% of the indirect photodegradation. Read More

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Antifungal peptides from a strain suppress basal stem rot disease of oil palm.

Phytopathology 2021 Jun 22. Epub 2021 Jun 22.

Bogor Agricultural University Faculty of Mathematics and Natural Science, 314301, Department of Biology, Bogor, Jawa Barat, Indonesia.

Basal stem rot (BSR) is the most common disease of oil palm ( Jacq.) in Southeast Asia. BSR is caused by a white-rot fungus . Read More

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Compilation of selenium metabolites data in selenized yeasts.

Metallomics 2021 Jun 22. Epub 2021 Jun 22.

National Research Council Canada, 1200 Montreal Road, Ottawa, Ontario, Canada.

Selenium-enriched yeast has long been recognized as an important nutritional source of selenium and studies have suggested that supplementation with this material provides chemo-preventative benefits beyond those observed for selenomethionine supplementation, despite the fact that selenomethionine accounts for 60-84% of the total selenium in selenized yeasts. There is much ongoing research into the characterization of the species comprising the remaining 16-40% of the selenium, with nearly 100 unique selenium-containing metabolites identified in aqueous extracts of selenized yeasts (Saccharomyces cerevisiae). Herein, we discuss the analytical approaches involved in the identification and quantification of these metabolites, and present a recently created online database (DOI: 10. Read More

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Deep residual-convolutional neural networks for event positioning in a monolithic annular PET scanner.

Phys Med Biol 2021 Jun 21. Epub 2021 Jun 21.

Department of Radiology/PET, Robert Byrd Health Sciences Center, One Medical Center Dr., Box 9236, Morgantown, West Virginia, 26506, UNITED STATES.

PET scanners based on monolithic pieces of scintillator can potentially produce superior performance characteristics (high spatial resolution and detection sensitivity, for example) compared to conventional PET scanners. Consequently, we initiated development of a preclinical PET system based on a single 72mm-long annulus of LYSO, called AnnPET. While this system could facilitate creation of high-quality images, its unique geometry results in optics that can present a challenge to the estimation of event positioning in the detector. Read More

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HPLC-UV-HRMS analysis of cannabigerovarin and cannabigerobutol, the two impurities of cannabigerol extracted from hemp.

J Pharm Biomed Anal 2021 Jun 16;203:114215. Epub 2021 Jun 16.

Institute of Nanotechnology - CNR NANOTEC, Campus Ecotekne, Via Monteroni, 73100, Lecce, Italy; Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125, Modena, Italy. Electronic address:

A sensitive and straightforward HPLC-UV method was developed for the simultaneous quantification of the two main impurities in "pure" commercial cannabigerol (CBG) samples. The identification of such impurities, namely cannabigerovarin (CBGV) and cannabigerobutol (CBGB), the propyl and butyl homologs of CBG, respectively, was accomplished employing the high-resolution mass spectrometry (HRMS) technique, and subsequently confirmed by comparison with the same compounds obtained by chemical synthesis. Complete spectroscopic characterization (NMR, FT-IR, UV, and HRMS) of both impurities is reported in the present work. Read More

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Exploring personal chemical exposures in China with wearable air pollutant monitors: A repeated-measure study in healthy older adults in Jinan, China.

Environ Int 2021 Jun 19;156:106709. Epub 2021 Jun 19.

Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT 06520, USA. Electronic address:

The health impact of airborne contaminants has been challenging to assess due to current limitations in measurement technologies. The emergence of wearable passive samplers coupled with high resolution mass spectrometry (HR-MS) chemical analysis has enabled comprehensive characterization of personal exposures. We conducted a repeated-measure study among 84 older adults in Jinan, China, as part of the Biomarkers for Air Pollutants Exposure (China BAPE) study. Read More

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On-surface autosampling for liquid chromatography-mass spectrometry.

J Chromatogr A 2021 Jun 8;1651:462334. Epub 2021 Jun 8.

Chair of Food Science, Institute of Nutritional Science, and Interdisciplinary Research Center (iFZ), Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany. Electronic address:

An on-surface multi-purpose autosampler was built for liquid chromatography-mass spectrometry (LC-MS) based on the autoTLC-MS interface, taking advantage of open-source hard- and software developments as well as 3D printing. Termed autoTLC-LC-MS system, it is introduced for orthogonal hyphenation of normal phase high-performance thin-layer chromatography with reversed phase high-performance LC (HPLC) and high-resolution MS (HRMS). For verification of its functionality, a multi-class antibiotic mixture was applied as a calibration band pattern on an adsorbent layer and detected by the Bacillus subtilis bioassay. Read More

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Xenopus laevis Egg Extract Preparation and Live Imaging Methods for Visualizing Dynamic Cytoplasmic Organization.

J Vis Exp 2021 Jun 6(172). Epub 2021 Jun 6.

Department of Chemical and Systems Biology, Stanford University School of Medicine; Department of Biochemistry, Stanford University School of Medicine.

Traditionally used for bulk biochemical assays, Xenopus laevis egg extracts have emerged as a powerful imaging-based tool for studying cytoplasmic phenomena, such as cytokinesis, mitotic spindle formation and assembly of the nucleus. Building upon early methods that imaged fixed extracts sampled at sparse time points, recent approaches image live extracts using time-lapse microscopy, revealing more dynamical features with enhanced temporal resolution. These methods usually require sophisticated surface treatments of the imaging vessel. Read More

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PBP4-mediated β-lactam resistance among clinical strains of Staphylococcus aureus.

J Antimicrob Chemother 2021 Jun 21. Epub 2021 Jun 21.

Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, USA.

Background: PBP4, a low-molecular-weight PBP in Staphylococcus aureus, is not considered to be a classical mediator of β-lactam resistance. Previous studies carried out by our group with laboratory strains of S. aureus demonstrated the ability of PBP4 to produce β-lactam resistance through mutations associated with the pbp4 promoter and/or gene. Read More

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Resolution of fibrosis by siRNA HSP47 in vitamin A coupled liposomes induces regeneration of chronically injured livers.

J Gastroenterol Hepatol 2021 Jun 20. Epub 2021 Jun 20.

Department of Molecular Target Exploration, Sapporo Medical University School of Medicine, Sapporo, Japan.

Background And Aim: In chronic hepatic diseases where treatment strategies are not available, deposited fibrotic tissues deteriorate the intrinsic regeneration capacity of the liver by creating special restrictions. Thus, if the anti-fibrosis modality is efficiently applied, the regeneration capacity of the liver should be reactivated even in such refractory hepatic diseases.

Methods: Rat liver fibrosis was induced by dimethyl-nitrosamine (DMN). Read More

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Optical Control of CD8 T Cell Metabolism and Effector Functions.

Front Immunol 2021 3;12:666231. Epub 2021 Jun 3.

Department of Microbiology and Immunology, David H. Smith Center for Vaccine Biology and Immunology, University of Rochester Medical Center, Rochester, NY, United States.

Although cancer immunotherapy is effective against hematological malignancies, it is less effective against solid tumors due in part to significant metabolic challenges present in the tumor microenvironment (TME), where infiltrated CD8 T cells face fierce competition with cancer cells for limited nutrients. Strong metabolic suppression in the TME is often associated with impaired T cell recruitment to the tumor site and hyporesponsive effector function T cell exhaustion. Increasing evidence suggests that mitochondria play a key role in CD8 T cell activation, effector function, and persistence in tumors. Read More

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Genomic and Chemical Investigation of Bioactive Secondary Metabolites From a Marine-Derived Fungus P2648.

Front Microbiol 2021 4;12:600991. Epub 2021 Jun 4.

Institute of Oceanography, Minjiang University, Fuzhou, China.

Marine fungi of the genus are rich resources of secondary metabolites, showing a variety of biological activities. Our anti-bacterial screening revealed that the crude extract from a coral-derived fungus P2648 showed strong activity against some pathogenic bacteria. Genome sequencing and mining uncovered that there are 28 secondary metabolite gene clusters in P2648, potentially involved in the biosynthesis of antibacterial compounds. Read More

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Unraveling the Ergot Alkaloid and Indole Diterpenoid Metabolome in the Species Complex Using LC-HRMS/MS Diagnostic Fragmentation Filtering.

J Agric Food Chem 2021 Jun 20. Epub 2021 Jun 20.

London Research and Development Center, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada.

The plant parasitic fungus sensu lato produces sclerotia containing toxic ergot alkaloids and uncharacterized indole diterpenoids in grasses including cereals. The aim of this study was to detect as many peptide ergot alkaloids and indole diterpenoids in ergot sclerotia as possible by using a liquid chromatography-high-resolution mass spectrometry (LC-HRMS/MS) approach and applying filtering of diagnostic fragment ions for data extraction. The sample set consisted of 66 sclerotia from four different geographic locations in southeastern Norway as well as Saskatchewan, Canada. Read More

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Developing Unique Nontarget High-Resolution Mass Spectrometry Signatures to Track Contaminant Sources in Urban Waters.

Environ Sci Technol Lett 2020 ;7(12)

Southern California Coastal Water Research Project Authority, Costa Mesa, California 92626, United States.

Diffuse pollution in urban receiving waters often adversely impacts both humans and ecosystems. Identifying such pollution sources is challenging and limits the effectiveness of management actions intended to reduce risk. Here, we evaluated the use of nontarget analysis via high-resolution mass spectrometry (HRMS) to develop chemical fingerprints/signatures for source tracking. Read More

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January 2020

A merged method for targeted analysis of amino acids and derivatives using parallel reaction monitoring combined with untargeted profiling by HILIC-Q-Orbitrap HRMS.

J Pharm Biomed Anal 2021 Jun 15;203:114208. Epub 2021 Jun 15.

Frontiers Science Center for Disease-related Molecular Network, Institutes for Systems Genetics, West China Hospital, Sichuan University, Chengdu, 610041, China. Electronic address:

With continuously increased scan rate and sensitivity, high resolution mass spectrometry (HRMS) allows for both reliable targeted analysis (e.g., parallel reaction monitoring, PRM) and a global overview for discovery-based untargeted profiling (e. Read More

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Affinity ultrafiltration and UPLC-HR-Orbitrap-MS based screening of thrombin-targeted small molecules with anticoagulation activity from Poecilobdella manillensis.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Jun 8;1178:122822. Epub 2021 Jun 8.

School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China. Electronic address:

This study aims to screen potential anticoagulant components from leeches, a representative animal-sourced traditional Chinese medicine using thrombin (THR)-targeted ultrafiltration combined with ultrahigh performance liquid chromatography and high-resolution Orbitrap mass spectrometry (UPLC-HR-Orbitrap-MS). As a result, five small molecules in leech extract were discovered to interact with THR for the first time. Among them, two new compounds were isolated and their structures were identified by IR, HR-MS and NMR data. Read More

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The impact of nasal adhesions on airflow and mucosal cooling - a computational fluid dynamics analysis.

Respir Physiol Neurobiol 2021 Jun 17:103719. Epub 2021 Jun 17.

Mechanical & Automotive Engineering, School of Engineering, RMIT University, Bundoora, Victoria 3083, Australia. Electronic address:

Nasal adhesions are a known postoperative complication following surgical procedures for nasal airway obstruction (NAO); and are a common cause of surgical failure, with patients often reporting significant NAO, despite relatively minor adhesion size. Division of such nasal adhesions often provides much greater relief than anticipated, based on the minimal reduction in cross-sectional area associated with the adhesion. The available literature regarding nasal adhesions provides little evidence examining their quantitative and qualitative effects on nasal airflow using objective measures. Read More

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Mass drug administration for the acceleration of malaria elimination in a region of Myanmar with artemisinin-resistant falciparum malaria: a cluster-randomised trial.

Lancet Infect Dis 2021 Jun 17. Epub 2021 Jun 17.

Medical Action Myanmar, Yangon, Myanmar; Myanmar Oxford Clinical Research Unit, Yangon, Myanmar; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK. Electronic address:

Background: To contain multidrug-resistant Plasmodium falciparum, malaria elimination in the Greater Mekong subregion needs to be accelerated while current antimalarials remain effective. We evaluated the safety, effectiveness, and potential resistance selection of dihydroartemisinin-piperaquine mass drug administration (MDA) in a region with artemisinin resistance in Myanmar.

Methods: We did a cluster-randomised controlled trial in rural community clusters in Kayin (Karen) state in southeast Myanmar. Read More

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Chlorine isotope analysis of polychlorinated organic pollutants using gas chromatography-high resolution mass spectrometry and evaluation of isotope ratio calculation schemes by experiment and numerical simulation.

J Chromatogr A 2021 Jun 4;1651:462311. Epub 2021 Jun 4.

State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. Electronic address:

Compound-specific isotope analysis of chlorine (CSIA-Cl) is a practicable and high-performance approach for revelation of transformation processes and source identification of chlorinated organic pollutants. This study conducted CSIA-Cl for typical polychlorinated organic pollutants using gas chromatography-high resolution mass spectrometry (GCHRMS) with an alternate injection mode using perchloroethylene (PCE) and trichloroethylene (TCE) as model analytes. PCE and TCE standards from two manufacturers were employed for method development, and chlorine isotope ratio calculation schemes were evaluated by experiment and numerical simulation. Read More

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Post-tonsillectomy hemorrhage control with nebulized tranexamic acid: A retrospective cohort study.

Int J Pediatr Otorhinolaryngol 2021 Jun 12;147:110802. Epub 2021 Jun 12.

Department of Otolaryngology & Head and Neck Surgery, Long School of Medicine, The Univesity of Texas Health Science Center, San Antonio, TX, USA; Department of Pediatrics, Long School of Medicine, The Univesity of Texas Health Science Center, San Antonio, TX, USA. Electronic address:

Objective: Evaluate nebulized tranexamic acid (TXA) as a treatment to reduce the need for an operation to control a post-tonsillectomy hemorrhage (PTH).

Methods: Based on a successful case report of a child treated with nebulized TXA for PTH in 2018, our institution began to treat PTH patients with three doses of nebulized TXA. To evaluate the outcomes of this non-invasive management, we conducted a three-year retrospective cohort study of children presenting with PTH from 2016 to 2019. Read More

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Pterocarpus santalinus L. extract mitigates gamma radiation-inflicted derangements in BALB/c mice by Nrf2 upregulation.

Biomed Pharmacother 2021 Jun 16;141:111801. Epub 2021 Jun 16.

Sree Vidyanikethan Engineering College, Tirupati 517102, Andhra Pradesh, India.

Plant-based natural extracts contain several nutrients and bioactive compounds, such as phenolics and flavonoids, that possess various health-promoting activities. This study investigated the effects of polyphenols from Pterocarpus santalinus hydroalcoholic extract (PSHE) against gamma radiation-induced derangements via the upregulation of Nrf2. Ultra High Performance Liquid Chromatography Coupled to High Resolution Mass Spectrometry (UHPLC-HRMS/MS) analysis was performed to identify the possible radioprotectors. Read More

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Measurement of lipogenic flux by deuterium resolved mass spectrometry.

Nat Commun 2021 06 18;12(1):3756. Epub 2021 Jun 18.

Center for Human Nutrition, The University of Texas Southwestern Medical Center, Dallas, TX, USA.

De novo lipogenesis (DNL) is disrupted in a wide range of human disease. Thus, quantification of DNL may provide insight into mechanisms and guide interventions if it can be performed rapidly and noninvasively. DNL flux is commonly measured by H incorporation into fatty acids following deuterated water (HO) administration. Read More

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Visceral Obesity Promotes Lung Cancer Progression-Toward Resolution of the Obesity Paradox in Lung Cancer.

J Thorac Oncol 2021 May 25. Epub 2021 May 25.

Department of Thoracic Surgery, Roswell Park Comprehensive Cancer Center, Buffalo, New York. Electronic address:

Introduction: Although obesity is associated with adverse cancer outcomes in general, most retrospective clinical studies suggest a beneficial effect of obesity in NSCLC.

Methods: Hypothesizing that this "obesity paradox" arises partly from the limitations of using body mass index (BMI) to measure obesity, we quantified adiposity using preoperative computed tomography images. This allowed the specific determination of central obesity as abdominal visceral fat area normalized to total fat area (visceral fat index [VFI]). Read More

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Novel Steroidal Saponins in Oat Identified by Molecular Networking Analysis and Their Levels in Commercial Oat Products.

J Agric Food Chem 2021 Jun 18. Epub 2021 Jun 18.

Laboratory for Functional Foods and Human Health, Center for Excellence in Post-Harvest Technologies, North Carolina Agricultural and Technical State University, North Carolina Research Campus, 500 Laureate Way, Kannapolis, North Carolina 28081, United States.

Through the use of the Global Natural Product Social (GNPS) feature-based networking system, a series of newly identified steroidal saponins were discovered in oat. The structures of the three new major steroidal saponins, sativacosides A-C (-), were characterized by analyzing their high-resolution MS, 1D and 2D NMR spectra, and an additional eight new steroidal saponins were also tentatively identified (-) based on their tandem mass spectra and typical fragments. Using ultrahigh-performance liquid chromatography with tandem mass spectrometry techniques, a complete profile of the new sativacoside series was established, and the contents of sativacosides A-C were quantified in 18 different commercial oat products. Read More

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Deciphering the Chemistry of Cultural Heritage: Targeting Material Properties by Coupling Spectral Imaging with Image Analysis.

Acc Chem Res 2021 Jun 18. Epub 2021 Jun 18.

Université Paris-Saclay, CNRS, ministère de la culture, UVSQ, MNHN, IPANEMA, F-91192 Saint-Aubin, France.

ConspectusThe chemical study of materials from natural history and cultural heritage, which provide information for art history, archeology, or paleontology, presents a series of specific challenges. The complexity of these ancient and historical materials, which are chemically heterogeneous, the product of alteration processes, and inherently not reproducible, is a major obstacle to a thorough understanding of their making and long-term behavior (e.g. Read More

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