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SUMMARY The distributions of monolignol glucosides (MLGs) in compression and opposite woods of Pinus thunbergii were assessed using cryo‐time‐of‐flight secondary ion mass spectrometry to investigate their involvement in lignification. p‐Glucocoumaryl alcohol (PG) was identified in the region of the differentiating xylem adjacent to the cambial zone only in compression wood, whereas coniferin (CF) was similarly localized in both compression and opposite woods. Their distribution from the phloem to the xylem was evaluated by high‐performance liquid chromatography (HPLC) using serial tangential sections. Variations in storage amounts of CF and PG in the stem of P. thunbergii agreed with lignification stages of the tracheid, supporting the idea that MLGs act as a storage and transportation form of lignin precursors. The imaging of monolignol (ML)‐dependent active lignification sites using fluorescence‐tagged MLs supported distinct distribution patterns of MLGs for lignification in compression and opposite woods. Methylation–thioacidolysis was applied to compression and opposite wood samples to examine the structural difference between the guaiacyl (G) and p‐hydroxyphenyl (H) units in lignin. Most of the H units in compression wood were detected as lignin end groups via thioacidolysis. PG was detected in opposite wood by HPLC; however, the H unit was not detected by thioacidolysis. The differences in ML and MLG distributions, enzyme activity, and resultant lignin structures between the G and H units suggest the possibility of individual mechanisms regulating the heterogeneous structures of G and H unit in lignin. [ABSTRACT FROM AUTHOR]

Abeliophyllum distichum (Oleaceae), endemic to the Korean Peninsula and the sole member of its genus and species, possesses high scarcity value, escalating its importance under the Nagoya Protocol. Despite its significance, their metabolites and activities of A. distichum flowers remain unexplored. This study employs an integrated metabolomic approach utilizing NMR, LC/MS, GC/MS, and FTIR techniques to comprehensively analyze the metabolite profile of A. distichum flowers. By combining these methods, we identified 35 metabolites, 43 secondary metabolites, and 108 hydrophobic primary metabolites. Notably, distinct concentration patterns of these compounds were observed across five variants, classified based on morphological characteristics. Correlation analyses of primary and secondary metabolites unveiled varietal metabolic flux, providing insights into A. distichum flower metabolism. Additionally, the reconstruction of metabolic pathways based on dissimilarities in morphological traits elucidates variant‐specific metabolic signatures. These findings not only enhance our understanding of chemical differences between varieties but also underscore the importance of considering varietal differences in future research and conservation efforts. [ABSTRACT FROM AUTHOR]

Abstract Abeliophyllum distichum (Oleaceae), endemic to the Korean Peninsula and the sole member of its genus and species, possesses high scarcity value, escalating its importance under the Nagoya Protocol. Despite its significance, their metabolites and activities of A. distichum flowers remain unexplored. This study employs an integrated metabolomic approach utilizing NMR, LC/MS, GC/MS, and FTIR techniques to comprehensively analyze the metabolite profile of A. distichum flowers. By combining these methods, we identified 35 metabolites, 43 secondary metabolites, and 108 hydrophobic primary metabolites. Notably, distinct concentration patterns of these compounds were observed across five variants, classified based on morphological characteristics. Correlation analyses of primary and secondary metabolites unveiled varietal metabolic flux, providing insights into A. distichum flower metabolism. Additionally, the reconstruction of metabolic pathways based on dissimilarities in morphological traits elucidates variant‐specific metabolic signatures. These findings not only enhance our understanding of chemical differences between varieties but also underscore the importance of considering varietal differences in future research and conservation efforts.

Abstract This study presents the first-ever synthesis of samarium-doped indium vanadate nanosheets (IVONSs:Sm) via microemulsion-mediated solvothermal method. The nanosheets were subsequently utilized as a nano-matrix in laser desorption/ionization mass spectrometry (LDI-MS). It was discovered that the as-synthesized IVONSs:Sm possessed the following advantages: improved mass spectrometry signal, minimal matrix-related background, and exceptional stability in negative-ion mode. These qualities overcame the limitations of conventional matrices and enabled the sensitive detection of small biomolecules such as fatty acids. The negative-ion LDI mechanism of IVONSs:Sm was examined through the implementation of density functional theory simulation. Using IVONSs:Sm-assisted LDI-MS, fingerprint recognitions based on morphology and chemical profiles of endogenous/exogenous compounds were also achieved. Notably, crucial characteristics such as the age of an individual’s fingerprints and their physical state could be assessed through the longitudinal monitoring of particular biomolecules (e.g., ascorbic acid, fatty acid) or the specific biomarker bilirubin glucuronide. Critical information pertinent to the identification of an individual would thus be facilitated by the analysis of the compounds underlying the fingerprint patterns. Graphical Abstract

The stable isotopic compositions of carbon and oxygen (δ13Ccarb and δ18Ocarb) measured from carbonates are widely used in geology, notably to reconstruct paleotemperatures and the secular evolution of the biogeochemical carbon cycle, to characterize limestone sediment diagenesis, and to provide chemostratigraphy records. The standard technique used since the mid-20th century to measure C and O isotopic ratios is based on a wet chemical acid digestion protocol in order to evolve CO2 from carbonates—the latter being analyzed by mass spectrometry and, more recently, infrared spectroscopy. A newly developed laser-based method aims to circumvent this chemical preparation step by producing CO2 via an instant and spatially resolved calcination reaction. We describe an evolution of the laser calcination benchtop system previously described and used as a proof of concept toward a portable system, and we present the efficiency of this tool for performing carbon and oxygen isotope measurements from carbonate matrixes following standard evaluation metrology protocol. This metrological study explores the following: i) the use of internal standards; ii) inter-calibration with the traditional acid chemical preparation method; iii) analysis of the uncertainties of using GUM and ANOVA. Using 15 different types of carbonate minerals encompassing a range of isotopic VPDB compositions between −18.6‰ and +16.06‰ and between −14.80‰ and −1.72‰ for δ13Ccarb and δ18Ocarb, we show that isotopic cross-calibration is verified for both carbon and oxygen, respectively, and we demonstrate that the uncertainties (1σ) of the δ13Ccarb and δ18Ocarb measurements of laser–laser isotopic analysis are within 0.41‰ and 0.68‰, respectively. The advantages of this method in saving time and spatially resolved and automated analysis in situ are demonstrated by high-resolution chemostratigraphic analysis of a laminated lacustrine travertine sample.

This study presents the first-ever synthesis of samarium-doped indium vanadate nanosheets (IVONSs:Sm) via microemulsion-mediated solvothermal method. The nanosheets were subsequently utilized as a nano-matrix in laser desorption/ionization mass spectrometry (LDI-MS). It was discovered that the as-synthesized IVONSs:Sm possessed the following advantages: improved mass spectrometry signal, minimal matrix-related background, and exceptional stability in negative-ion mode. These qualities overcame the limitations of conventional matrices and enabled the sensitive detection of small biomolecules such as fatty acids. The negative-ion LDI mechanism of IVONSs:Sm was examined through the implementation of density functional theory simulation. Using IVONSs:Sm-assisted LDI-MS, fingerprint recognitions based on morphology and chemical profiles of endogenous/exogenous compounds were also achieved. Notably, crucial characteristics such as the age of an individual's fingerprints and their physical state could be assessed through the longitudinal monitoring of particular biomolecules (e.g., ascorbic acid, fatty acid) or the specific biomarker bilirubin glucuronide. Critical information pertinent to the identification of an individual would thus be facilitated by the analysis of the compounds underlying the fingerprint patterns. [ABSTRACT FROM AUTHOR]

Influenza A virus (IAV) is a respiratory virus that causes epidemics and pandemics. Knowledge of IAV RNA secondary structure in vivo is crucial for a better understanding of virus biology. Moreover, it is a fundament for the development of new RNA-targeting antivirals. Chemical RNA mapping using selective 2’-hydroxyl acylation analyzed by primer extension (SHAPE) coupled with Mutational Profiling (MaP) allows for the thorough examination of secondary structures in low-abundance RNAs in their biological context. So far, the method has been used for analyzing the RNA secondary structures of several viruses including SARS-CoV-2 in virio and in cellulo. Here, we used SHAPE-MaP and dimethyl sulfate mutational profiling with sequencing (DMS-MaPseq) for genome-wide secondary structure analysis of viral RNA (vRNA) of the pandemic influenza A/California/04/2009 (H1N1) strain in both in virio and in cellulo environments. Experimental data allowed the prediction of the secondary structures of all eight vRNA segments in virio and, for the first time, the structures of vRNA5, 7, and 8 in cellulo. We conducted a comprehensive structural analysis of the proposed vRNA structures to reveal the motifs predicted with the highest accuracy. We also performed a base-pairs conservation analysis of the predicted vRNA structures and revealed many highly conserved vRNA motifs among the IAVs. The structural motifs presented herein are potential candidates for new IAV antiviral strategies. [ABSTRACT FROM AUTHOR]

Tire and road wear particles (TRWP) consist of tread rubber elastomers with pavement encrustations generated from tire-road friction. Our previous work utilized density separation and chemical mapping to characterize chemical and physical properties of individual TRWP. The current research extends the use of chemical mapping methods to urban river samples including sediment from the Seine River (France). TRWP were identified using a weight of evidence framework including density separation, optical imaging, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDX) mapping, and Fourier-transform infrared (FTIR) spectroscopy. River sediment collected immediately downstream of the Rouen urban area (with an average TRWP concentration of 930 mg TRWP/kg sediment; n = 3) subsequently density separated demonstrated an average TRWP size of 133 µm by number and 171 µm by volume. Sediment from a second location (190 mg TRWP/kg sediment; n = 1) was density separated and showed an overlap in features of tire tread and bitumen/asphalt in the FTIR signatures (operationally defined as weathered bitumen/TRWP). Average particle size for weathered bitumen/TRWP were 250 µm and 981 µm by number and volume, respectively. Pulverization pre-treatment of the second location sediment sample reduced larger particle agglomerates to an average weathered bitumen/TRWP particle size of 97 µm and 116 µm by number and volume, respectively. A quantitative TRWP or bitumen/TRWP size distribution in filtered suspended river solids (3300 mg TRWP/kg suspended solid) could not be determined due to lack of TRWP enrichment in pre- or post-density separation steps; however, average particle size for all collected river particles were 27 µm and 160 µm by number and volume, respectively. Additionally, TRWP were not identified in a river biota sample (bivalves) with or without chemical digestion and future research was discussed. Taken together, our single particle analysis methodologies were useful for the determination of particle size distribution (including bitumen and TRWP) in urban river sediment samples. These results are expected to help advance the methods for identification and characterization of TRWP and potentially other microplastics in various environmental matrices.

• Microorganisms could cause erosion and degrade waterlogged archeological wood which leads to irreversible damage. Due to the correlation between fungi and "mineral content" within the timber still unclear, and research on the structure of cell will much help to understand the germination and formation of microorganisms on the wooden relics. • The advance soft X-ray microscopy imaging -based on synchrotron radiation, can tomographic reconstruction of whole cell with high-resolution three-dimensional structure of biological specimen, and can be combined with the chemical mapping technique to obtain the three-dimensional elements distribute in interior cell of samples, and reconstructed the cellular and subcellular structures of sample with in situ analysis. • Results showing much of new information from cell architecture and remodeling the inorganic component distribute with organelles and surface of cell, which provide more knowledge and understanding about the microbial interactions with wooden cultural relics. Microorganisms will induce biodeterioration and destruction to ancient wooden cultural heritages. The "Nanhai No. 1" shipwreck sank off at the Southern Song dynasty (1127∼1279 CE) and was salvaged to land in December 2007. After the wreck was salvaged from the seawater and stored in the museum, it was found that fungal hyphae appeared on the hull in certain places. Further examination revealed that the fungal infection tended to appear in areas enriched with sulfur and iron compounds. Therefore, analyzing the formation and germination of fungi in waterlogged archeological wood and whether it is related to inorganic compounds is a question that needs to be addressed in the conservation of marine shipwrecks. Here, based on synchrotron radiation technology, integrating X-ray absorption fine structures with full-field transmission X-ray microscope to analyze the iron component and demonstrate its distribution within a single spore, which probably traces the interaction between inorganic elements with cell and subcellular constituents. In conclusion, the results demonstrate soft X-ray tomographic generating 3-D reconstructions associated with chemical mapping of whole spore and illustrate the power and potential ability of synchrotron radiation-based techniques to study cultural heritage and its conservation application. [Display omitted] [ABSTRACT FROM AUTHOR]

The application of Laser-Induced Breakdown Spectroscopy (LIBS) is presented for the direct elemental analysis of hydrocarbon-rich solids. In recent years, LIBS has become a powerful tool for obtaining elemental information and mapping analysis of different petroleum-rich samples with minimal to no sample preparation and without the need to separate the organic matter from the inorganic matter. By selecting the most intense and representative lines, the element distribution in a 2D map can be accessed in less than ten hours. For this reason, two types of hydrocarbon-rich solids were chosen for examination, i.e., core and shale. Nineteen elements were identified in the samples, and 2D mapping for Ca, Mg, Fe, Ti, Ni, C, H, K, O, and S is presented here. A detailed distribution of the elements, and the main components of the hydrocarbons present in these samples, were determined using LIBS. The H/C molar ratio was determined by building H and C calibration curves using data obtained from classical elemental analysis via combustion. These calibration curves contained a high degree of linearity (R2 > 0.98) with the limits of detection for C (193 nm), C (247 nm), and H (656 nm) of 848 mg kg−1, 353 mg kg−1, and 3.5 mg kg−1, respectively. By combining all of this information, LIBS allowed us to determine how these elements were spatially distributed, which elements were dominant in a given sample, and how much hydrocarbon was present, as well as providing a quantitative determination of the H/C molar ratio, and its correlation with the source of origin.

This paper implements machine learning (ML) classification algorithms on microstructural chemical maps to predict the constituent phases. Intensities of chemical species (Ca, Al, Si, etc.), and in some cases the nanomechanical properties measured at the corresponding points, form the input to the ML model, which predicts the phase label (LD or HD C-S-H, clinker etc.) belonging to that location. Artificial neural networks (ANN) and forest ensemble methods are used for classification. Confusion matrices and receiver-operator characteristic (ROC) curves are used to analyze the classification efficiency. It is shown that, for complex microstructures such as those of ultra-high performance (UHP) pastes, the classifier performs well when nanomechanical information augments the chemical intensity data. For simpler systems such as well-hydrated plain cement pastes, the classifier accurately predicts the phase label from the intensities of Ca, Al, and Si alone. The work enables fast-and-efficient phase identification and property forecasting from microstructural chemical maps.

Spectroscopic instruments were a part of payloads on orbiter and lander missions and delivered vast data sets to explore minerals, elements and molecules on air-less rocky planets, asteroids and comets on global and local scales. To answer current space science questions, the chemical composition of planetary rocks and soils at grain scale is required, as well as measurements of element (isotope) concentrations down to the part per million or lower. Only mass spectrometric methods equipped with laser sampling ion sources can deliver the necessary information. Laser sampling techniques can reduce the dimensions of the investigated sample material down to micrometre scale, allowing for the composition analysis of grain-sized objects or thin mineral layers with sufficiently high spatial resolution, such that important geological processes can be recognised and studied as they progressed in time. We describe the performance characteristics, when applied to meteorite and geological samples, of a miniaturised laser ablation/ionisation mass spectrometer (named LMS) system that has been developed in our group. The main advantages of the LMS instrument over competing techniques are illustrated by examples of high spatial (lateral and vertical) resolution studies in different meteorites, terrestrial minerals and fossil-like structures in ancient rocks for most elements of geochemical interest. Top-level parameters, such as dimension, weight, and power consumption of a possible flight design of the LMS system are presented as well. [ABSTRACT FROM AUTHOR]

Sedimentary geochemistry is very often associated with the measurement of isotopic composition of carbon and oxygen from carbonates. The usual technique combining acid digestion and mass spectrometry analysis is slow, costly and non-ideal for spatially resolved analyses. When carbonates are processed using laser calcination and the gas produced during calcination is analyzed by infrared spectrometry, the time required for isotopic analysis is reduced to around 15 min to analyze 30 mg of carbonate in situ. Although the time saved is significant, it is hardly reasonable to carry out a high-resolution isotopic mapping of large samples. A fully resolved isotopic mapping, for example, of a sample with 25 cm2 surface area at resolution of a tenth of a millimeter, would require a continuous measurement carried out for a month. The aim of this study is, therefore, to explore possible strategies for constructing an isotopic map with a minimum number of analyses. Two approaches are pro-posed: (i) a mathematical approach that seeks to establish a correlation between the position of the sample and the carbon or oxy-gen isotopes, and (ii) an approach that looks for a correlation between the color (spectral characteristics) of the sample surface subdomains and their isotopic compositions. The choice of the second approach stems from the assumption that color contains a priori information about geological or geochemical processes. Several algorithms were developed and tested, notably using artificial intelligence tools. To testify the isotopic maps produced by these algorithms, posteriori isotopic measurements are taken and compared with the predictions from computed isotopic maps. [ABSTRACT FROM AUTHOR]

The semiconductor industry has seen tremendous progress over the last few decades with continuous reduction in transistor size to improve device performance. Miniaturization of devices has led to changes in the dopants and dielectric layers incorporated. As the gradual shift from two-dimensional metal-oxide semiconductor field-effect transistor to three-dimensional (3D) field-effect transistors (finFETs) occurred, it has become imperative to understand compositional variability with nanoscale spatial resolution. Compositional changes can affect device performance primarily through fluctuations in threshold voltage and channel current density. Traditional techniques such as scanning electron microscope and focused ion beam no longer provide the required resolution to probe the physical structure and chemical composition of individual fins. Hence advanced multimodal characterization approaches are required to better understand electronic devices. Herein, we report the study of 14 nm commercial finFETs using atom probe tomography (APT) and scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy (STEM-EDS). Complimentary compositional maps were obtained using both techniques with analysis of the gate dielectrics and silicon fin. APT additionally provided 3D information and allowed analysis of the distribution of low atomic number dopant elements (e.g., boron), which are elusive when using STEM-EDS.

The application of Laser-Induced Breakdown Spectroscopy (LIBS) is presented for the direct elemental analysis of hydrocarbon-rich solids. In recent years, LIBS has become a powerful tool for obtaining elemental information and mapping analysis of different petroleum-rich samples with minimal to no sample preparation and without the need to separate the organic matter from the inorganic matter. By selecting the most intense and representative lines, the element distribution in a 2D map can be accessed in less than ten hours. For this reason, two types of hydrocarbon-rich solids were chosen for examination, i.e., core and shale. Nineteen elements were identified in the samples, and 2D mapping for Ca, Mg, Fe, Ti, Ni, C, H, K, O, and S is presented here. A detailed distribution of the elements, and the main components of the hydrocarbons present in these samples, were determined using LIBS. The H/C molar ratio was determined by building H and C calibration curves using data obtained from classical elemental analysis via combustion. These calibration curves contained a high degree of linearity (R2 > 0.98) with the limits of detection for C (193 nm), C (247 nm), and H (656 nm) of 848 mg kg−1, 353 mg kg−1, and 3.5 mg kg−1, respectively. By combining all of this information, LIBS allowed us to determine how these elements were spatially distributed, which elements were dominant in a given sample, and how much hydrocarbon was present, as well as providing a quantitative determination of the H/C molar ratio, and its correlation with the source of origin. [ABSTRACT FROM AUTHOR]

In the present work we summarize the first achievements of the RockStar Group of the Department of Physics and Geology (at the University of Perugia, Italy), which is made of a strict collaboration between Physicists and Geologists on astrophysical and planetological studies. The RockStar Group acts on two research lines: (i) astrophysical modeling and (ii) mineralogical and geochemical studies of meteorites. In the first part of the article we review the recent results concerning the development of theoretical modeling of nucleosynthesis and mixing process in asymptotic giant branch. In the second part we report (1) the catalog of the Meteorite collection of University of Perugia and (2) major and trace elements mapping, performed through EPMA and LA-ICP-MS, of the Mineo pallasite, a unique sample hosted by the collection. The new data constrain the Mineo meteorite among the Main Group Pallasites and support the hypothesis of the "early giant impact" formation. [ABSTRACT FROM AUTHOR]

Various phenomena in living physiological systems are conducted on the hydrated conditions, and in many cases, they do not work in a dry state. Imaging mass spectrometry is one of the direct detection methods scanning the sample surface with some focused and pulsed energy and analysing the sputtered components. However, under the high vacuum conditions required for usual imaging mass spectrometry, the sample surface is rapidly dried. It is difficult for the target cell to survive, and the original situation are lost soon. Here, the combination of a freeze-fixation and a cryo sample stage is a promising method to do mass spectrometry while maintaining the original situation. By rapidly freezing the cells, the momentary situation as a living cell is fixed. The situation in a living cell can be captured as still images by cryo imaging mass spectrometry. This mini-review introduces the outline of imaging mass spectrometry especially for low molecular weight components and recent results for frozen-hydrated samples by cryo secondary ion mass spectrometry. [ABSTRACT FROM AUTHOR]

This paper implements machine learning (ML) classification algorithms on microstructural chemical maps to predict the constituent phases. Intensities of chemical species (Ca, Al, Si, etc.), and in some cases the nanomechanical properties measured at the corresponding points, form the input to the ML model, which predicts the phase label (LD or HD C-S-H, clinker etc.) belonging to that location. Artificial neural networks (ANN) and forest ensemble methods are used for classification. Confusion matrices and receiver-operator characteristic (ROC) curves are used to analyze the classification efficiency. It is shown that, for complex microstructures such as those of ultra-high performance (UHP) pastes, the classifier performs well when nanomechanical information augments the chemical intensity data. For simpler systems such as well-hydrated plain cement pastes, the classifier accurately predicts the phase label from the intensities of Ca, Al, and Si alone. The work enables fast-and-efficient phase identification and property forecasting from microstructural chemical maps. [ABSTRACT FROM AUTHOR]

Standard techniques for geochemical and mineralogical characterisation are time‐consuming, they can involve significant sample preparation and they are prone to error. The aim of this work is to show how the emerging fast laser‐induced breakdown spectroscopy (LIBS) technique can be valuable for mineral exploration. For this purpose, the well‐established micro‐X‐ray fluorescence (µ‐XRF) technique was used to validate the LIBS data. Two ore samples from the platinum‐group elements (PGE) Lac des Îles mine (Ontario, Canada) were analysed both by LIBS and µ‐XRF. The fast mineralogical and elemental mapping provided by LIBS allowed the identification of four major silicate phases (chlorite, bytownite, actinolite, hornblende) and four minor sulfide phases (Pd‐bearing pentlandite, chalcopyrite, pyrrhotite, pyrite). Multi‐element chemical mapping and mineral characterisation using µ‐XRF corroborated the LIBS analyses for the composition, distribution and abundance of minerals in PGE ore samples. These findings demonstrate the ability of the LIBS technique to perform direct fast high‐resolution mapping of the chemical and mineralogical composition of PGE ore samples. This work highlights the advantages of LIBS for this application of being much faster and more sensitive to trace elements (e.g., Pd), as well as to low atomic number elements. [ABSTRACT FROM AUTHOR]

Spectroscopic instruments were a part of payloads on orbiter and lander missions and delivered vast data sets to explore minerals, elements and molecules on air-less rocky planets, asteroids and comets on global and local scales. To answer current space science questions, the chemical composition of planetary rocks and soils at grain scale is required, as well as measurements of element (isotope) concentrations down to the part per million or lower. Only mass spectrometric methods equipped with laser sampling ion sources can deliver the necessary information. Laser sampling techniques can reduce the dimensions of the investigated sample material down to micrometre scale, allowing for the composition analysis of grain-sized objects or thin mineral layers with sufficiently high spatial resolution, such that important geological processes can be recognised and studied as they progressed in time. We describe the performance characteristics, when applied to meteorite and geological samples, of a miniaturised laser ablation/ionisation mass spectrometer (named LMS) system that has been developed in our group. The main advantages of the LMS instrument over competing techniques are illustrated by examples of high spatial (lateral and vertical) resolution studies in different meteorites, terrestrial minerals and fossil-like structures in ancient rocks for most elements of geochemical interest. Top-level parameters, such as dimension, weight, and power consumption of a possible flight design of the LMS system are presented as well.

The use of falsified and unregistered drugs is a worldwide public health problem. Because these global market products usually do not follow the Good Manufacturing Practices required by health legislation, its composition may be completely different from the original or may contain relevant concentrations of impurities and toxic contaminants. Since anabolic steroids are among the main irregular therapeutic classes seized in Brazil, here we propose a new methodology for analyzing these products, in tablets form, using Attenuated Total Reflection Fourier Transform Infrared Microspectroscopy (µATR‐FTIR) mapping. Spectra were acquired from solid tablets by attenuated total reflection, through point mapping methodology. In data processing, a characteristic absorption band for each Active Pharmaceutical Ingredient (API) was integrated and plotted to create its distribution map. This technique was applied in an unprecedented way for the forensic analysis of anabolic steroids and proved to be effective in distinguishing falsified products based on the detection of their APIs. It was possible to detect APIs in 26 out of 30 samples, five of which were classified as falsified only through µATR‐FTIR analysis. We were able to create distribution maps of the detected substances associating the microspectroscopic results with characteristic band integration method, which can be used to detect substances and to study samples' homogeneity. We concluded that this methodology is promising for the analysis of anabolic steroid tablets, and can be used in a complementary way with techniques already consolidated in forensic laboratory routine for a better classification of questioned samples between authentic and falsified ones. [ABSTRACT FROM AUTHOR]

Featured Application: We present analysis strategies for soft X-ray transmission imaging data focused on the study of chemical and morphological properties of cathode material for lithium batteries. Energy-dependent full field transmission soft X-ray microscopy (TXM) is able to give a full picture at the nanometer scale of the chemical state and spatial distribution of oxygen and other elements relevant for battery materials, providing pixel-by-pixel absorption spectrum. We show different methods to localize chemical inhomogeneities in Li1.2Mn0.56Ni0.16Co0.08O2 particles with and without VOx coating extracted from electrodes at different states of charge. Considering the 3d(Mn,Ni)-2p(O) hybridization, it has been possible to discriminate the chemical state of Mn and Ni in addition to the one of O. Different oxidation states correspond to specific features in the O-K spectra. To localize sample regions with specific compositions we apply two different methods. In the first, the pixel-by-pixel ratios of images collected at different key energies clearly highlight local inhomogeneities. In the second, introduced here for the first time, we directly correlate corresponding pixels of the two images on a xy scatter plot that we call phase map, where we can visualize the distributions as function of thickness as well as absorption artifacts. We can select groups of pixels, and then map regions with similar spectral features. Core-shell distributions of composition are clearly shown in these samples. The coating appears in part to frustrate some of the usual chemical evolution. In addition, we could directly observe several further aspects, such as: distribution of conducting carbon; inhomogeneous state of charge within the electrode; molecular oxygen profiles within a particle. The latter suggests a surface loss with respect to the bulk but an accumulation layer at intermediate depth that could be assigned to retained O2. [ABSTRACT FROM AUTHOR]

This study developed a reliable laser‐induced breakdown spectroscopy (LIBS) screening approach capable of detecting GSR in just a few minutes with minimal damage to the sample, high specificity, and sensitivity. Moreover, a novel micro‐sampling method was developed to gather three‐dimensional data of the simultaneous occurrence of IGSR markers from a discrete space. The method is capable of micro‐spatial chemical analysis from just two laser shots fired at an area of 100‐μm diameter. The performance of the micro‐spot method is compared with our previously published bulk‐line method. Superior accuracy, spatial information of IGSR distribution in the sample, and a less invasive sampling are some of the advantages of the newly proposed method. A benefit afforded by this approach is the use of the universal hand's collection method currently used by practitioners, while leaving over 99% of the stub left unaltered for further analysis. Machine learning algorithms were used for the classification of samples derived from shooters' hands versus nonshooters hands, based on their LIBS spectrochemical data. Four different approaches—critical threshold, logistic regression, naïve Bayes, and neural networks—were applied to examine the performance and accuracy of two different ablation patterns (micro‐spot and bulk‐line mode). A validation set of 326 samples originated from 51 nonshooters and 56 known shooters resulted in an overall accuracy between 87% and 100%, depending on the ablation pattern and the type of prediction model applied. The incorporation of this rapid screening and statistical decision‐making approach could offer more efficient case management in firearm‐related investigations. A LIBS method capable of documenting the distribution of IGSR markers on substrates dabbed from an individual's hands was developed. The 3D data include simultaneous information about the analyte characteristic wavelengths, their respective intensity, and x‐y location coordinates within the sample. Logistic regression, naïve Bayes, and neural network machine learning models provided effective predictive methods, with classification accuracy better than 93.7% for a validation set of 326 authentic samples collected from shooters and background populations. [ABSTRACT FROM AUTHOR]

Sequence census methods reduce molecular measurements such as transcript abundance and protein-nucleic acid interactions to counting problems via DNA sequencing. We focus on a novel assay utilizing this approach, called selective 2'-hydroxyl acylation analyzed by primer extension sequencing (SHAPE-Seq), that can be used to characterize RNA secondary and tertiary structure. We describe a fully automated data analysis pipeline for SHAPE-Seq analysis that includes read processing, mapping, and structural inference based on a model of the experiment. Our methods rely on the solution of a series of convex optimization problems for which we develop efficient and effective numerical algorithms. Our results can be easily extended to other chemical probes of RNA structure, and also generalized to modeling polymerase drop-off in other sequence census-based experiments.

In the present work we summarize the first achievements of the RockStar Group of the Department of Physics and Geology (at the University of Perugia, Italy), which is made of a strict collaboration between Physicists and Geologists on astrophysical and planetological studies. The RockStar Group acts on two research lines: (i) astrophysical modeling and (ii) mineralogical and geochemical studies of meteorites. In the first part of the article we review the recent results concerning the development of theoretical modeling of nucleosynthesis and mixing process in asymptotic giant branch. In the second part we report (1) the catalog of the Meteorite collection of University of Perugia and (2) major and trace elements mapping, performed through EPMA and LA-ICP-MS, of the Mineo pallasite, a unique sample hosted by the collection. The new data constrain the Mineo meteorite among the Main Group Pallasites and support the hypothesis of the “early giant impact” formation.

Direct nano-scale microanalysis is important for photovoltaic functional thin films to characterize their homogeneity and purity. This demands combining spatial resolution in the micro/nano-scale and sensitivity in the trace-level range, which is at the moment beyond state-of-the-art. As dictated by counting statistics, the reduction of the spot size degrades the detection limit. The utilization of a tabletop XUV laser at λ = 46.9 nm has shown to dramatically improve the ablation efficiency with respect to that of visible lasers, such that ablation spot of 1 μm limits. Li-doped Cu2ZnSn(S,Se)4 (so-called kesterite) thin films were irradiated across 3D ablation arrays for hyperspectral mapping by means of time-of-flight mass spectrometry. The nominal 3D data node lattices were the initialisation perceptron, filled with measured values, and for a detailed supervised learning postprocessing, the node-to-node links were analysed by means of a 2D-kernel covariance algorithm. The latter permitted to obtain robust 3D elemental distribution functions well below the measurement spacing, giving insights into the inhomogeneity and impurities. [ABSTRACT FROM AUTHOR]

We demonstrate that unstained DNA nanostructures can be chemically mapped by using aberration-corrected scanning transmission electron microscopy (STEM) with energy-dispersive spectroscopy (EDS). Key to this measurement is the use of graphene supports whose reduced background scattering compared to thicker carbon supports allows EDS to image phosphorus and other elements in the DNA (or in attachments to the DNA) as well as to see the divalent cations used to stabilize the nanostructure. In addition, unlike in other EDS analyses, the chemical maps we obtain can be made quantitative in an absolute sense because each individual DNA nanostructure is in effect a very large macromolecule (∼4.7 MDa) with a known chemical composition. In this way, not only can STEM/EDS serve DNA nanotechnology as a characterization tool but also the DNA structures can function as molecular standards for improving mesoscale EDS techniques. [ABSTRACT FROM AUTHOR]

Exposure to arsenic (As) through drinking water results in accumulation of As and its methylated metabolites in several organs, promoting adverse health effects, particularly potential development of cancer. Arsenic toxicity is a serious global health concern since over 200 million people are chronically exposed worldwide. Abundant biochemical and epidemiological evidence indicates that the kidney is an important site of uptake and accumulation of As, and mitochondrial damage plays a crucial role in arsenic toxicity. However, non-destructive analyses and in situ images revealing As fate in renal cells and tissue are scarce or almost non-existent. In this work, kidney tissue from exposed rats was analyzed by EDXRF (Energy dispersive X-ray fluorescence), micro-SRXRF (micro X-ray Fluorescence using Synchrotron Radiation), SRTXRF (SRXRF in total reflection condition), SEM-EDX (Scanning Electron Microscope in combination with EDXRF) and SRXRF-XANES (SRXRF in combination with X-ray Absorption Near Edge Spectroscopy). Our results provide evidence of renal cortex distribution of As with periglomerular localization, co-localization of S, Cu and As in subcellular compartment of proximal tubule cells, mono-methylarsonous acid accumulation in renal cortex mitochondria, and altered subcellular concentration and distribution of other elements. • The distribution of As in renal tissue was analyzed without pre-treatment. • SRXRF and SEM-EDX allowed corroborate co-location of Cu and As in proximal convoluted tubules. • For the first time, the compartmentation of arsenic in the renal tubules is shown in images. • The most toxic species of As MMAIII, accumulates in mitochondria. • X-ray Fluorescence Spectroscopy provides an accurate and high-resolution picture of As bioaccumulation. [ABSTRACT FROM AUTHOR]

Neutral water splitting is attractive for its use of non-corrosive and environmentally friendly electrolytes. However, catalyst development for hydrogen and oxygen evolution remains a challenge under neutral conditions. Here we report a simple electrodeposition and reductive annealing procedure to produce a highly active Ni-Co-Cr metal/metal oxide heterostructured catalyst directly on Ni foam. The resulting electrocatalyst for hydrogen evolution reaction (HER) requires only 198 mV of overpotential to reach 100 mA/cm2 in 1 M potassium phosphate (pH = 7.4) and can operate for at least two days without significant performance decay. Scanning transmission electron microscopy coupled with electron energy loss spectroscopy (STEM-EELS) imaging reveals a Ni-Co alloy core decorated with blended oxides layers of NiO, CoO and Cr2O3. The metal/metal oxide interfaces are suggested to be responsible for the high HER activity. [ABSTRACT FROM AUTHOR]

Highlights • It is convenient to obtain infrared spectral chemical images of DAI lesions. • Chemical images reveal the distribution of molecular groups in a color-insensitive manner. • The molecular distribution characteristics reflected by DAI chemical images were verified. Abstract The diagnosis of diffuse axonal injury (DAI) is an important task in forensic pathology and clinical medicine. This study aimed to explore the use of Fourier transform infrared spectroscopy (FTIR) to detect DAI. The DAI area of the rat model was detected point by point by the FTIR-mapping system. Infrared spectral data of DAI were obtained by selecting the amide A band, CH 3 symmetric stretching, collagen triple-helix structure and asymmetric stretching vibrational frequency of nucleic acid and phospholipid PO 2 as the target peak positions. The system can automatically draw infrared spectral color pathological images. In the DAI group, the amide A protein secondary amine N–H stretching vibration and the collagen triple-helix structure of the high-absorption area were consistent with the DAI area confirmed by the silver and β-APP staining. The CH 3 symmetric stretching, nucleic acid and phospholipid PO 2 symmetric stretching vibration absorption spectra showed no significant differences between the experimental and verification groups. The FTIR-mapping technique can visually express the molecular characteristics of DAI, which is expected to be applied to the pathological diagnosis of DAI. [ABSTRACT FROM AUTHOR]

Raman spectroscopy and micro-Raman mapping have been used to study the distribution of different chemical components at the surface of coated papers. The paper coatings contain organic nanoparticles with a structure of poly(styrene-co-maleimide) and encapsulated vegetable oils. Raman spectroscopy is able to differentiate between various types of oil, i.e., polyunsaturated, monounsaturated, or saturated, and indicates that the degree of imidization and reactivity of the oil (amount of free oil) complement each other. The surface mapping over large areas (5 × 5 mm2) illustrates good homogeneity of the coating layer and even surface coverage. The imide and oil are homogeneously distributed within the coating itself without a tendency for agglomeration. The covered areas of imide and oil mostly overlap for polyunsaturated oils, while larger amounts of oil occur outside the imide zones for monounsaturated and saturated oils. The latter indicates that the oil is partly "free" within the coating and acts as a continuous binder phase. The surface mapping over smaller areas (1 × 1 mm2) shows the coating and cellulose covered areas are complementary. The surface maps confirm that interaction between the coating and paper substrate happens through hydrogen bonding. Heterogeneities in the coating are due to the presence of remaining ammonolyzed maleic anhydride precursors forming amic acid moieties. The organic phase, oil phase, and cellulose substrate can also be differentiated by principal component analysis of the surface maps. [ABSTRACT FROM AUTHOR]

Abstract In the last decade, Mesoamerican codices have been the subjects of numerous characterization studies. Due to their large sizes, a limited number of areas were effectively analyzed, but considered representative of the manuscripts material constituents. In order to overcome this necessary assumption, a complementary approach is presented here, with the use of macroscopic diffuse reflectance spectral imaging (also known as "hyperspectral" imaging), in the visible to short wave infrared range (400–2500 nm). It allowed to study the entire surface of the Codex Borbonicus , a 16th century Aztec manuscript, used as an example of application for our innovative methodology. Numerous types of information (colorimetric data, visualization of underdrawings, spectral segmentation and chemical mappings) were obtained, and the entire document material composition was examined. These new data enrich the current knowledge on traditional Mesoamerican manuscript manufacturing techniques. More importantly, this demonstrates the great potential of this approach for the non-invasive study of large polychromatic surfaces. For the first time, an entire manuscript is analyzed using this approach providing several types of information on the same document with a single analytical technique. [ABSTRACT FROM AUTHOR]

Energy-dependent full field transmission soft X-ray microscopy (TXM) is able to give a full picture at the nanometer scale of the chemical state and spatial distribution of oxygen and other elements relevant for battery materials, providing pixel-by-pixel absorption spectrum. We show different methods to localize chemical inhomogeneities in Li1.2Mn0.56Ni0.16Co0.08O2 particles with and without VOx coating extracted from electrodes at different states of charge. Considering the 3d(Mn,Ni)-2p(O) hybridization, it has been possible to discriminate the chemical state of Mn and Ni in addition to the one of O. Different oxidation states correspond to specific features in the O-K spectra. To localize sample regions with specific compositions we apply two different methods. In the first, the pixel-by-pixel ratios of images collected at different key energies clearly highlight local inhomogeneities. In the second, introduced here for the first time, we directly correlate corresponding pixels of the two images on a xy scatter plot that we call phase map, where we can visualize the distributions as function of thickness as well as absorption artifacts. We can select groups of pixels, and then map regions with similar spectral features. Core-shell distributions of composition are clearly shown in these samples. The coating appears in part to frustrate some of the usual chemical evolution. In addition, we could directly observe several further aspects, such as: distribution of conducting carbon; inhomogeneous state of charge within the electrode; molecular oxygen profiles within a particle. The latter suggests a surface loss with respect to the bulk but an accumulation layer at intermediate depth that could be assigned to retained O2.

The functionality of RNA is fully dependent on its structure. For the influenza A virus (IAV), there are confirmed structural motifs mediating processes which are important for the viral replication cycle, including genome assembly and viral packaging. Although the RNA of strains originating from distant IAV subtypes might fold differently, some structural motifs are conserved, and thus, are functionally important. Nowadays, NGS-based structure modeling is a source of new in vivo data helping to understand RNA biology. However, for accurate modeling of in vivo RNA structures, these high-throughput methods should be supported with other analyses facilitating data interpretation. In vitro RNA structural models complement such approaches and offer RNA structures based on experimental data obtained in a simplified environment, which are needed for proper optimization and analysis. Herein, we present the secondary structure of the influenza A virus segment 5 vRNA of A/California/04/2009 (H1N1) strain, based on experimental data from DMS chemical mapping and SHAPE using NMIA, supported by base-pairing probability calculations and bioinformatic analyses. A comparison of the available vRNA5 structures among distant IAV strains revealed that a number of motifs present in the A/California/04/2009 (H1N1) vRNA5 model are highly conserved despite sequence differences, located within previously identified packaging signals, and the formation of which in in virio conditions has been confirmed. These results support functional roles of the RNA secondary structure motifs, which may serve as candidates for universal RNA-targeting inhibitory methods.

Synchrotron Radiation Fourier Transform Infrared Microspectroscopy (SR-FTIR microspectroscopy) is a unique technique of 2D structural-chemical analysis that has been used successfully in diverse research fields. However, food scientists still seldom know this advanced analytical technique despite its huge potential in food research. Integration of SR-FTIR microspectroscopy with food science, requires comprehensive understanding of this emerging structural-chemical analytical technique. This article detailed the fundamental theory, working principle, mode of action, relevancy and constraints of application as well as capacity of integrating SR-FTIR microspectroscopy in food industries to assist in process optimization, quality control and safety confirmation. SR-FTIR microspectroscopy combines distinct working principle of spectroscopy and microscopy within IR spectral range, where high intensity light from synchrotron facility is used to achieve some advantages over other analytical approaches. This hyphenated technique has shown its capability to provide 2D structural-chemical information of food cereal grains, oil grains, processed food, foodborne pathogens, and so on, instigating this technique to be used for food processing, preservation, quality monitoring, and safety aspects. Despite the accessibility issue of SR-FTIR microspectroscopy, its application is flourishing and demands more exploration as an emerging food analytical technique. [ABSTRACT FROM AUTHOR]

Conventional sensing methods report on concentrations of analytes in a single point of sampled medium or provide an average value. However, distributions of substances on surfaces of sampled objects often exhibit intricate inhomogeneities. In order to obtain snapshots of the chemical distributions on surfaces, we have developed enzyme-loaded hydrogel arrays (5 × 5 and 10 × 10). The acrylic 10 × 10 array base contains 100 holes, which are filled with agarose hydrogel containing assay enzymes and substrates. Such arrays can be exposed to the analyzed surfaces to collect minute amounts of analytes. Following a brief incubation, they are subsequently visualized in a custom-built array reader device. The reader incorporates a light-emitting diode-based light source, miniature camera, and Raspberry Pi single-board computer. Two Python programs capture and analyze the images of the array to extract pixel saturation values corresponding to individual hydrogel micropatches. The method has been thoroughly optimized for mapping of glucose and lactic acid. The optimized parameters were: contact time, agarose concentration, substrate concentration, enzyme concentration ratio, and enzyme concentration. The array biosensor was further tested by mapping glucose distribution in fruit/vegetable cross-sections (apple, guava, and cucumber) and lactic acid distribution in cheese. We think that this new hydrogel-based chemical mapping method can find applications in studies related to food science, plant physiology, clinical chemistry, and forensics; wherever the distributions of analytes on the tested surfaces need to be assessed. [Display omitted] [ABSTRACT FROM AUTHOR]

We investigated and overcame the limitations associated with the use of unmanned aerial vehicles (UAVs) in the chemical mapping of pollutants coming from point source, as in the case of leaks’ detection. In particular, by simulating the pollutant spatial distribution in the absence and presence of a flying drone, we demonstrated that turbulent flows generated by UAVs can significantly limit the spatial accuracy of the mapping and the pollutant source detection. Finally, as this effect markedly depends on the proximity of the UAV to the pollutant source, we experimentally demonstrated that it is possible to overcome it by employing a sufficiently long probe equipped with an aspiration apparatus transporting the sample from the ground to the detector-equipped UAV.

Our research group previously reported a novel method for the detection of gunshot residue (GSR) via tape lifting combined with Raman microspectroscopic mapping and multivariate analysis. This initial study achieved proof of concept for this approach. Here, we report validation studies which investigate the reproducibility/ruggedness and specificity of the approach. Raman mapping for GSR detection on adhesive tape was performed on an independent Raman microscope, not used to generate the training set. These independent spectra were classified against the original training dataset using support vector machine discriminant analysis (SVM-DA). The resulting classification rates of 100% illustrate the reproducibility of the technique, its independence upon a specific instrument and provide an external validation for the approach. Additionally, the same procedure for GSR collection (tape lifting) was performed to collect samples from environmental sources, which could potentially provide false-positive assignments for current GSR analysis techniques. Thus, particles associated with automotive mechanics were collected. Automotive brake and tire materials are often composed of the heavy metals lead, barium, and antimony, which are the key elements targeted by current GSR detection technique. It was determined that Raman spectroscopic analysis was not susceptible to misclassifications from these samples. Results from these validation experiments illustrate the great potential of Raman microspectroscopic mapping used with tape lifting as a viable complimentary tool to current methodologies for GSR detection. Furthermore, current methodologies are not well-developed for automated organic GSR detection. Illustrated here, Raman microscoptrosocpic mapping has the potential for the automatic identification of organic GSR.ᅟ [ABSTRACT FROM AUTHOR]

This paper describes a detailed chemical characterization of connector pins separated from diverse electronic components removed from waste printed circuit boards (WPCB) of computers. Chemical maps by SEM-EDS (Scanning Electron Microscopy - Energy Dispersive Spectroscopy) indicated that the substrates of all connector pins are made by Cu-Sn, Cu-Zn or Cu-Sn-Zn alloys, which are covered by thin Ni and Au layers. The ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometry) analysis of the different connector pins revealed that these materials are mostly constituted by Cu (62-88% w/w) and very attractive Au contents were found (up to 1273 g/t). For all pins, intermediate contents of Zn, low contents of Ni, Sn and Pb and very low contents of Pd and Fe were determined. A heterogeneous, 100% metallic sample was prepared by mixing all individual connector pins aiming at contribute to the development of feasible technologies for recovering valuable metals. The mixed sample contains about 73% w/w Cu and 168 g/t Au, which are higher than the contents reported in the literature for samples obtained after grinding assembled or disassembled WPCB. The leaching of the mixed sample without grinding and concentration steps will reduce operating costs and maximize metals recovery avoiding mass losses. [ABSTRACT FROM AUTHOR]

Effective properties and structural performance of cementitious mixtures are substantially governed by the quality of the interphase region because it acts as a bridge transferring forces between aggregates and a binding matrix and is generally susceptible to damage. As alternative binding agents like alkali-activated precursors have obtained substantial attention in recent years, there is a growing need for fundamental knowledge to uncover interphase formation mechanisms. In this paper, two different types of binding materials, i.e., fly ash-based geopolymer and ordinary portland cement, were mixed with limestone aggregate to examine and compare the microstructures and nanomechanical properties of interphase region. To this end, microstructural characteristics using scanning microscopies, nanomechanical properties by nanoindentation tests, and spatial mapping of chemical contents based on the energy dispersive spectroscopy were integrated to identify and investigate the interphase region formed by the case-specific interactions between the matrix materials and limestone. The integrated microstructural-nanomechanical-chemical approach was effective to better understand links between material-specific properties of cementing phases. More specifically, the fly ash-based geopolymer paste was usually well bonded to the aggregate surface with a rich formation of N-A-S-H gel, while interfacial debonding was often observed between aggregate surface and paste in ordinary portland cement concrete. However, when a good bonding between aggregate and paste is formed, interphase region in PCC did not show any considerable difference in nanomechanical properties compared to the bulk paste. [ABSTRACT FROM AUTHOR]

Arsenic (As) groundwater contamination is common yet spatially heterogeneous within most environments. It is therefore necessary to measure As concentrations to determine whether a water source is safe to drink. Measurement of As in the field involves using a test strip that changes color in the presence of As. These tests are relatively inexpensive, but results are subjective and provide binned categorical data rather than exact determinations of As concentration. The goal of this work was to determine if photos of field kit test strips taken on mobile phone cameras could be used to extract more precise, continuous As concentrations. As concentrations for 376 wells sampled from Araihazar, Bangladesh were analyzed using ICP-MS, field kit and the new mobile phone photo method. Results from the field and lab indicate that normalized RGB color data extracted from images were able to accurately predict As concentrations as measured by ICP-MS, achieving detection limits of 9.2 μg/L, and 21.9 μg/L for the lab and field respectively. Data analysis is most consistent in the laboratory, but can successfully be carried out offline following image analysis, or on the mobile phone using basic image analysis software. The accuracy of the field method was limited by variability in image saturation, and variation in the illumination spectrum (lighting) and camera response. This work indicates that mobile phone cameras can be used as an analytical tool for quantitative measures of As and could change how water samples are analyzed in the field more widely, and that modest improvements in the consistency of photographic image collection and processing could yield measurements that are both accurate and precise. [ABSTRACT FROM AUTHOR]