This work addresses the problem of determining the number of components from sequential spectroscopic data analyzed by non-negative matrix factorization without separability assumption (SepFree NMF). These data are stored in a matrix M of dimension &...
Fourier-transform infrared spectroscopy (FT-IR), multispectral imaging (MSI), and an electronic nose (E-nose) were implemented individually and in combination in an attempt to investigate and, hence, identify the complexity of the phenomenon of spoil...
The ability to rapidly conduct in-situ chemical analysis of multiple samples of soil and other geological materials in the field offers many advantages over a traditional approach that involves collecting samples for subsequent examination in the lab...
Spectral preprocessing data and chemometric tools are analytical methods widely applied in several scientific contexts i.e., in archaeometric applications. A systematic classification of natural powdered pigments of organic and inorganic nature throu...
The roles of dissolved organic matter (DOM) in microbial processes and nutrient cycles depend on its composition, which requires detailed measurements and analyses. We introduce a package for R, called staRdom (“spectroscopic analysis of DOM in...
The rapid assessment of the microbiological quality of highly perishable food commodities is of great importance. Spectroscopic data coupled with machine learning methods have been investigated intensively in recent years, because of their rapid, non...
The Gaia DR3 GSP-spec/TESS (GST) catalog combines asteroseismic data from NASA’s TESS mission with spectroscopic data from ESA’s Gaia mission, and contains about 116,000 Red Clump and Red Giant Branch stars, surpassing previous datasets i...
The application described has been designed to create bibliographic entries in large databases with diverse sources automatically, which reduces both the frequency of mistakes and the workload for the administrators. This new system uniquely identifi...
Spectroscopic data allows for the obtaining of relevant information about the composition of samples and has been used for research in scientific disciplines such as chemistry, geology, archaeology, Mars research, pharmacy, and medicine, as well as i...
The correlation coefficient (CC) was substantiated as a simple, yet robust statistical tool in the quality assessment of hyperspectral imaging (HSI) data. The sensitivity of the metric was also characterized with respect to artificially-induced error...
Mid-infrared spectroscopy (MIR), near-infrared spectroscopy (NIR), and Raman spectroscopy are all well-established analytical techniques in biomedical applications. Since they provide complementary chemical information, we aimed to determine whether...
The most realistic information about a transparent sample such as a live cell can be obtained using bright-field light microscopy. Under high-intensity pulsing LED illumination, we captured a primary 12-bit-per-channel (bpc) response from an observed...
The methanol extract of an assemblage of Halimeda stuposa and a Dictyota sp., yielded three natural products characteristic of Dictyota sp., and one of Halimeda sp. These included the xenicane diterpene 4-hydroxydictyolactone (1), and the diterpenes...
The objective of this study was to evaluate differences between the red onion cultivar and breeding line using models based on selected fluorescence spectroscopic data built using machine-learning algorithms from different groups of Trees, Functions,...
The analysis of spectral reflectance data is an important tool for obtaining relevant information about the mineral composition of objects and has been used for research in chemistry, geology, biology, archaeology, pharmacy, medicine, anthropology, a...
Rangelands represent about 25% of the Earth’s land surface but are under severe pressure. Rangeland degradation is a gradually increasing global environmental problem, resulting in temporary or permanent loss of ecosystem functions. Ecological...
A data-fitting method based on the whale optimization algorithm (WOA) is proposed to determine the thickness and refractive index of films measured by spectroscopic ellipsometry (SE). To demonstrate this method, tin oxide (SnO2) films with transparen...
Prior to 2021, 4-bromo-1H-pyrazole (published in 1999) was the only structurally characterized 4-halogenated-1H-pyrazole in the Cambridge Crystallographic Data Center (CCDC). The structures of 4-chloro-1H-pyrazole and 4-fluoro-1H-pyrazole were publis...
Artificial-intelligence-based analysis methods can provide objective and accurate results. This study aimed to evaluate the performance of machine learning algorithms to classify yeast-inoculated and uninoculated tomato samples using fluorescent spec...
Spectral small-angle X-ray scattering (sSAXS) is a powerful technique for material characterization from thicker samples by capturing elastic X-ray scattering data in angle- and energy-dispersive modes at small angles. This approach is enabled by the...
2,3-Dichloroquinoxaline and some of its derivatives have been reacted with malononitrile and ethyl cyanoacetate to yield a variety of 3-chloro-2-(cyanomethylene)- 1,2-dihydroquinoxaline derivatives. The reaction of 3-chloro-2-(dicyanomethylene)-1,2-...
In the field of cultural heritage (CH), non-invasive analyses, such as photogrammetry and multiband imaging (MBI), play a pivotal role as effective solutions for examining the morphology, materials, and state of preservation of an artifact. Gathering...
The acid catalyzed esterification of 2,6-dimethoxybenzoic acid (1) in the presence of absolute ethanol afforded ethyl 2, 6-dimethoxybenzoate (2). The structure of the resulting compound was supported by spectroscopic data and unambiguously confirmed...
Vaping electronic cigarettes (e-cigarettes) has become a popular alternative to smoking tobacco. When an e-cigarette is activated, a liquid is vaporized by heating, producing an aerosol that users inhale. While e-cigarettes are marketed as less harmf...
In this study, a method of mid-level data fusion with the fingerprint region was proposed, which was combined with the characteristic wavelengths that contain fingerprint information in NIR and FT-MIR spectra to detect the DON level in FHB wheat duri...
The present study applied LA–ICP-MS on gem-quality emeralds from the most important sources (Afghanistan, Brazil, Colombia, Ethiopia, Madagascar, Russia, Zambia and Zimbabwe). It revealed that emeralds from Afghanistan, Brazil, Colombia and Madagasca...
Effects of processing and extraction solvents on antioxidant properties and other characteristics were evaluated for ten medicinal plant species originating from two different localities and two production years. A combination of spectroscopic and li...
A novel series of pyrido[2,3-d]pyrimidines; pyrido[3,2-e][1,3,4]triazolo; and tetrazolo[1,5-c]pyrimidines were synthesized via different chemical transformations starting from pyrazolo[3,4-b]pyridin-6-yl)-N,N-dimethylcarbamimidic chloride 3b (prepare...
Powders and films composed of tin dioxide (SnO2) are promising candidates for a variety of high-impact applications, and despite the material’s prevalence in such studies, it remains of high importance that commercially available materials meet...
The color change of the pink and colorless LiAlSi2O6 spodumene crystal due to irradiation and heating is explained. The hypothesis about the change of Mn3+ to Mn4+ after irradiation was rejected. For the studied crystals, it was shown that both Mn2+...
Dye-sensitized solar cell (DSC) technology has been broadly investigated over the past few decades. The sandwich-type structure of the DSC makes the manufacturing undemanding under laboratory conditions but results in the need for reproducible measur...
Medicinal plants extracts are a rich natural source of bioactive phytochemicals (mainly polyphenols). This study aims at determining the total polyphenols content (TPC) of nine medicinal plants extracted using the UV-visible (UV-Vis) spectroscopic me...
In order to improve the detection accuracy for the quality of wheat, a recognition method for wheat quality using the terahertz (THz) spectrum and multi-source information fusion technology is proposed. Through a combination of the absorption and the...
Gunshot residue (GSR) is an important type of forensic trace evidence produced when a firearm is discharged. Currently, inorganic GSR particles are used for establishing the fact of shooting. The organic gunshot residue (OGSR) has been recently shown...
Fourier transform infrared spectroscopy (FT-IR) and multispectral imaging (MSI) were evaluated for the prediction of the microbiological quality of poultry meat via regression and classification models. Chicken thigh fillets (n = 402) were subjected...
Fruit juices are one of the most adulterated beverages, usually because of the addition of water, sugars, or less expensive fruit juices. This study presents a method based on Fourier transform infrared spectroscopy (FT-IR), in combination with machi...
The present work highlights a new general method devoted to computations of the clamped linear electro-optical coefficients from the measured fundamental vibrational frequencies and the nonlinear dielectric susceptibility constants. The calculations...
Gorgostane steroids are isolated from marine organisms and consist of 30 carbon atoms with a characteristic cyclopropane moiety. From the pioneering results to the end of 2021, isolation, biosynthesis, and structural elucidation using 13C-NMR will be...
The cold-pressed oil from Japanese quince seeds (JQSO) is notable for its favorable fatty acid profile, low oxidation rate, and bioactive compounds like antioxidants, sterols, and carotenoids. This study offers a detailed molecular-level physical cha...
The lowest-energy isomer of C
Bucchero is a well-known class of Etruscan ceramics, characterized by being entirely black both on the surface and in the body. In the present investigation, a representative set of bucchero sherds from the excavations of the Etruscan town of Tarquin...
Near-infrared spectroscopy (NIRS) is widely used as a non-invasive method to monitor the hemodynamics of biological tissue. A common approach of NIRS relies on continuous wave (CW) methodology, i.e. utilizing intensity-only measurements, and, in gene...
One-hundred and fourteen samples of saffron harvested in four different Italian areas (three in Central Italy and one in the South) were investigated by IR and UV-Vis spectroscopies. Two different multi-block strategies, Sequential and Orthogonalized...
Oral potentially malignant disorders (OPMDs) are precursors to over 80% of oral cancers. Hematoxylin and eosin (H&E) staining, followed by pathologist interpretation of tissue and cellular morphology, is the current gold standard for diagnosis. H...
Pharmacological and nutraceutical effects of isoflavones, which include genistein (GE), are attributed to their antioxidant activity protecting cells against carcinogenesis. The knowledge of the oxidation mechanisms of an active substance is crucial...
Chemical image fusion refers to the combination of chemical images from different modalities for improved characterisation of a sample. Challenges associated with existing approaches include: difficulties with imaging the same sample area or having i...
The presence of minerals formed under the occurrence of liquid water during the first billion years on Mars was a key discovery, but there is still a large number of open issues that make the study of these mineral deposits a main focus of remote sen...
Polyhydroquinoline (PHQ) are the unsymmetrical Hantzsch derivatives of 1,4-dihydropyridines with several biological applications. In this work, twenty-five (3–27) new Schiff’s base derivatives of polyhydroquinoline hydrazide were synthesi...
Degradation of rebaudioside M, a minor sweet component of Stevia rebaudiana Bertoni, under conditions that simulated extreme pH and temperature conditions has been studied. Thus, rebaudioside M was treated with 0.1 M phosphoric acid solution (pH 2.0)...
Eight new chromones, engyodontiumones A–H (1–8), and three new phenol derivatives (9–11) together with eight known polyketides (12–19) were isolated from the deep-sea-derived fungus Engyodontium album DFFSCS021. Their structures were identified by ex...
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