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The aim of the article is to study the issues of analysis, modeling with the purpose of forecasting the payment of value added tax (VAT) on goods, works and services imported as imports into the customs territory of Ukraine. The reliability and validity of the planned VAT rate depend on the assessment of the status, forecast, seasonality and trends of economic and social development. The purpose of the work is to analyze and systematize the methodology for modeling VAT revenues from imports, justify the use of the econometric method and develop an adequate ARIMA model. It application is possible in the long term as well as smaller periods of time, which is relevant for monitoring and control of tax revenues. The study revealed the main factors influencing the application of the ARIMA model when modeling VAT revenues from imports. The resulting regression model in STATISTICA linked the variables with an accurate approximation. [ABSTRACT FROM AUTHOR]

We investigate the variability properties of blazars in the GeV band using data from the Fermi/Large Area Telescope (LAT) telescope. We find that blazars exhibit variability down to the minimum timescale resolvable by Fermi; this variability is a function of the peak photon count rate in the LAT. This implies that the real minimum variability timescales for the majority of blazars are typically shorter than those resolvable by the LAT. We find that for several blazars these minimum variability timescales reach those associated with the blazar central engine, the supermassive black hole. At the same time, none of the blazars exhibits variability on a timescale shorter than the black hole horizon light-crossing time and/or the period of rotation around the last stable circular orbit. Based on this fact, we argue that the timing properties of the γ -ray signal could be determined by the processes in the direct vicinity of the supermassive black hole. [ABSTRACT FROM AUTHOR]

A hypothesis about one of possible mechanisms of occurrence of wheezes (tonal sound signals) in a human bronchial tree at its pathologies is put forward. It is supposed that viscous sputum allocated in affected airways, can form aerodynamic structures of the nozzle-jet-obstacle type. A stenosis forming a high-speed jet plays the role of a nozzle in the act of breathing. The other stenosis, bifurcation of the airways or the sputum formations can play the role of an obstacle. An experimental installation was used to check the mentioned hypothesis. It included a physical model of an airway along with the equipment for recording and processing of the sound .signals and for estimation of the airflow velocity. As a result of experiments it was shown that presence of the specified aerodynamic structures can provide an efficient transformation of energy of the stream in airways into energy of the sound vibrations, which spectra are very similar to those of wheezes. A number of laws, being characteristic for the considered structures, is established. The threshold values of flow velocities when the tonal sound vibrations start to arise are estimated. It is shown that the relative distance between a stenosis forming a jet and an obstacle being increased, the threshold Reynolds numbers and the threshold frequencies of the tonal signals tend to a decrease, and the threshold Strouhal numbers - to an increase. [ABSTRACT FROM AUTHOR]

A problem of sound radiation by a bimorphic piezoceramic disk submerged in fluid and being excited by a harmonic in time electric voltage is solved within the scope of the theory of thin bimorphic piezoplates and using the method of partial domains. The cases are considered when the bimorphic disk is placed inside an infinite baffle (acoustically soft or hard). The disk's contour is implied to be free or simply supported. A numerical analysis of radiated power and directivity pattern for acoustical system under consideration is conducted. As a result, it is shown that, contrary to a widespread opinion, the free disk in the soft baffle is an efficient sound source. [ABSTRACT FROM AUTHOR]

Some physiological features of human respiratory tract important for establishing the adequate knowledge about the sources of the respiratory sounds are discussed. The understanding of peculiarities of such sound generation is necessary for creation of efficient computer systems for breath noise recording and processing intended for improvement of the respiratory diseases diagnostics. An essential multi parametric dependence of the respiratory sounds predetermines the necessity to document all these parameters in the process of measurements. One of the common parameters usually recorded in the process of measurement is the airflow rate measured with a pneumotachograph. On the basis of measuring the spread for the true glottis dimensions and estimation of the corresponding level of the respiration noise power spectrum we have shown that maintenance of predetermined airflow rate in different patients does not guarantee the same power levels of the respiratory sounds generated by airflow in the trachea. [ABSTRACT FROM AUTHOR]

A problem on sound propagation in traditional medical stethoscope is solved on the basis of analytical method of partial domains accounting for air viscosity. An expression for stethoscope's transmission function is obtained. The influence of geometric dimensions of stethoscope elements on its transmission function is investigated in details. Comparative analysis of theoretical and experimental data is carried out initial data for rational design of stethoscopes are obtained. [ABSTRACT FROM AUTHOR]

The analysis of peculiarities of trachea wall structure is conducted. Possible mechanisms of its excitation are discussed. The acoustical and mathematical models of trachea with elastic walls are developed. These models foresee the possibilities of kinematic excitation of the upper end of trachea and propagation of an elastic wave along the trachea wall. In the wide frequency range a quantitative analysis of modulus and phase of the oscillatory velocity of the trachea elastic wall is performed. These data are compared with those obtained for the acoustical mode! of trachea with locally responding walls. It is shown that the elastic wall behaves as a delay line, and an elastic wave can propagate along this line in the range of low frequencies (f < 500 Hz), having the speed about 10 &div; 20 m/sec. At higher frequencies the elastic wall behaves like a locally responding surface. It is shown that even relatively low levels of kinematics excitation of the upper end of trachea cause significant changes in the character of frequency dependence of the trachea wall oscillatory velocity. The analysis of the frequency dependencies of oscillatory velocities of the first seven annular cartilages of the trachea wall is performed. It is found that their levels diminish with the increase of the distance of cartilage from the upper end of trachea. The relatively simple technique allowing to estimate real values of the transmission function of the oscillatory velocity from vocal chords to the upper end of trachea is proposed. [ABSTRACT FROM AUTHOR]

Background and Purpose: The ligands of the imidazoline and α-adrenergic receptors are mainly imidazoline and guanidine derivatives, known as centrally-acting antihypertensives and compounds with potential use in various neurological disorders. The extent of their ionisation has a major influence on their behaviour in the different analytical systems. The main objective of this work was to compare the mechanism of chromatographic retention and electrophoretic mobility under acidic, neutral and basic conditions., Experimental Approach: Multiple Linear Regression and Partial Least Squares Regression were applied for the QSRR (quantitative structure-retention relationship) and QSMR (quantitative structure-mobility relationship) modelling and to select the most important molecular parameters describing the chromatographic and electrophoretic behaviour of the investigated compounds., Key Results: The most important molecular descriptors, such as the chemical composition of the compounds, lipophilicity, polarizability and molecular branching, in the selected QSRR models showed that an important insight into the retention behaviour can be derived from the 0D-, 1D- and 2D-descriptors. The electrophoretic mobility could be explained by 2D- and 3D-descriptors, which provide information on the molecular mass, size and complexity, as well as on the influence of charge transfer and electronic properties on the migration behaviour., Conclusion: All created QSRR/QSMR models met the stringent validation criteria and showed high potential in describing the chromatographic and electrophoretic behaviour of investigated compounds., Competing Interests: Conflict of interest: The authors declare no conflict of interest., (Copyright © 2024 by the authors.)

Bee pollen, known as a 'life-giving dust', is a product of honeybees using flower pollen grains and combining them with their saliva secretions. Thus, flower pollen could be an indicator of the bee pollen botanical source. Identification of bee pollen sources is a highly crucial process for the evaluation of its health benefits, as chemical composition is directly related to its pharmacological activity. In this study, the chemical profiles, contents of phenolic marker compounds and pharmacological activities of Hedera helix L. (ivy) bee pollen samples from Türkiye and Slovenia, as well as ivy flower pollen grains, were compared. High-performance thin-layer chromatography (HPTLC) analyses revealed that pollen samples, regardless of where they were collected, have similar chemical profiles due to the fact that they have the same botanical origins. Marker compounds afzelin, platanoside and quercetin-3- O -β-glucopyranosyl-(1→2)-β-galactopyranoside, common to both bee pollen and flower pollen, were isolated from bee pollen, and their structures were elucidated by nuclear magnetic resonance (NMR) and mass spectrometry (MS). These three compounds, as well as chlorogenic acid and 3,5-dicaffeoylquinic acid (found in flower pollen), were quantified using high-performance liquid chromatography (HPLC) analyses. In vitro tests and effect-directed analyses were used to evaluate the xanthine oxidase inhibition and antioxidant activity of the marker compounds and extracts from flower pollen and bee pollen. This is the first report comparing chemical profiles and related bioactivities of the flower pollen and bee pollen of the same botanical origin, as well as the first report of the chemical profile and related bioactivities of ivy flower pollen.

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

This narrative review summarizes epidemiological studies on breast cancer and prostate cancer with an overview of their global incidence distribution to investigate the relationship between these diseases and diet. The biological properties, mechanisms of action, and available data supporting the potential role of isoflavones in the prevention of breast cancer and prostate cancer are discussed. Studies evaluating the effects of isoflavones in tissue cultures of normal and malignant breast and prostate cells, as well as the current body of research regarding the effects of isoflavones attained through multiple modifications of cellular molecular signaling pathways and control of oxidative stress, are summarized. Furthermore, this review compiles literature sources reporting on the following: (1) levels of estrogen in breast and prostate tissue; (2) levels of isoflavones in the normal and malignant tissue of these organs in European and Asian populations; (3) average concentrations of isoflavones in the secretion of these organs (milk and semen). Finally, particular emphasis is placed on studies investigating the effect of isoflavones on tissues via estrogen receptors (ER).

The food supplement market is growing as many consumers wish to complement their nutrient intake. Despite all the regulations in place to ensure food supplements safety, there are still many cases of irregularities reported especially connected to internet sales. Twenty resveratrol food supplement products sold on the Slovenian market were evaluated on their compliance of declared vs. determined resveratrol content, as well as the compliance of labels with the European Union (EU) and Slovenian regulatory requirements. Both the ingredient contents and food information are important parts of food safety. Analyses of 20 food supplements performed using high-performance thin-layer chromatography (HPTLC) coupled with densitometry showed that 95% of products had contents different from what was declared and 55% of products contained higher contents than declared. In 25% of the products the determined content per unit exceeded the maximum level (150 mg/day) specified in EU novel food conditions for food supplement with trans -resveratrol. Evaluation of the 20 food supplement labels included mandatory and voluntary food information, food supplement information, novel food information, health claims and nutrition claims. Most labels contained the necessary information, but multiple errors were observed ranging from typos to misleading practices. From a food safety perspective there is still a lot of improvement needed in the field of food supplements.

Pomegranate fruit is an ancient fruit that is used not only because of its deep-red color and tasty arils but also due to the health benefits of its extracts. Pomegranate is a valuable source of bioactive compounds, including colorful anthocyanins and other polyphenols. The main objective of the present study was to gain comprehensive knowledge of the phenolic composition and antioxidative activity of a new pomegranate cultivar, grown in Northwest Istria, a part of the North Adriatic coastal area. Various parts of the pomegranate fruit parts were extracted in 70% ethanol or water. Total phenolic content and antioxidative capacity were respectively determined with Folin-Ciocalteu reagent and ABTS radical. Phenolics were examined and analyzed with TLC, LC-MS, and HPLC. Pomegranate juice was prepared from red arils and after thermal treatment, the stability of anthocyanins was monitored for several months to understand the effect of storage. The highest total phenolics were determined in ethanol pomegranate peel extracts (30.5 ± 0.6 mg GAE/g DM), and water peel extracts exhibited the highest antioxidative activity (128 ± 2 µg TE/g DM). After five months of storage of thermally treated pomegranate juice, 50-60 percentage points increase in anthocyanin degradation was observed. Pomegranate peel was further tested as a sustainable inedible food source for papermaking. Due to the low content of cellulose and the high percentage of extractives, as well as a distinguished texture and appearance, the paper made from pomegranate peel is best suited for the production of specialty papers, making it particularly interesting for bioactives recovery, followed by material restructuring.

The present work introduces a high-performance thin-layer chromatography (HPTLC)-direct bioautography method using the Gram-positive plant pathogenic bacterium, Rhodococcus fascians. The screening and isolation procedure comprised of a non-targeted high-performance thin-layer chromatography-effect-directed analysis (HPTLC-EDA) against Bacillus subtilis, B. subtilis subsp. spizizenii, R. fascians, and Aliivibrio fischeri, a targeted HPTLC-mass spectrometry (MS), and bioassay-guided column chromatographic (preparative flash and semi-preparative HPLC) fractionation and purification. The developed new separation methods enabled the discovery of four bioactive cis-clerodane diterpenes, solidagoic acid H (1), solidagoic acid E (2), solidagoic acid I (3), and solidagoic acid F (4), in the n-hexane extract of giant goldenrod (Solidago gigantea Ait.) leaf for the first time. These compounds were identified by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. The initially used HPTLC method (chloroform - ethyl acetate - methanol 15:3:2, V/V/V) was changed (to n-hexane - isopropyl acetate - methanol - acetic acid 29:20:1:1, V/V/V/V) to achieve the separation of the closely related isomer pairs (1-2 and 3-4). Compounds 1 and 3 exhibited moderate antibacterial activity against the Gram-positive B. subtilis subsp. spizizenii and R. fascians bacterial strains in microdilution assays with half-maximal inhibitory concentration (IC 50 ) values in the range of 32.3-64.4 µg/mL. The mass spectrometric fragmentation of the isolated compounds was interpreted and their previously published NMR assignments lacking certain resonances were completed., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2022. Published by Elsevier B.V.)

This study presents a detailed characterization of 27 honey samples from the Tara Mountain region in Serbia using different comprehensive techniques and methods. The types of the honey samples were defined as monofloral (4 samples), honeydew (5 samples) and polyfloral (18 samples) honey based on determined polyphenol content, antioxidant activity, electrical conductivity and melissopalynological analyses. Physicochemical parameters such as pH (4.13-4.94), diastase activity (24.20-41.70 DN), acidity (14.60-29.70 meq/kg), content of 5-(hydroxymethyl)furfural (in range below 5, up to 16.90 mg/kg), sucrose (0.20-3.90 g/100 g), and moisture content (15.01-19.23%) confirmed the required quality of the honey samples. Sensory analysis revealed honey characteristics favorable to consumers. Analyses of 19 phenolic compounds using ultra-high-performance liquid chromatography with a diode-array detection and triple quadrupole mass spectrometry (UHPLC-DAD-MS/MS) revealed six phenolic acids and 13 other compounds from the group of flavonoids and their glycosides. In all the samples the highest content was determined for p -coumaric acid, followed by caffeic acid and pinocembrin. Besides total phenolic content and radical scavenging activity, antimicrobial activity was also examined. Most honey samples showed bactericidal activity against Staphylococcus aureus and bacteriostatic activity against Escherichia coli , while none of the honey samples inhibited the growth of Candida albicans . Chemometric analyses were applied for an in-depth study of the results to further evaluate the characteristics of the honey samples studied. Principal component analysis (PCA) was used for assessing the differences in physicochemical parameters, polyphenols content and antioxidant capacity between honey samples. The unrooted cluster tree was used to group the samples based on the melissopalynological analyses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Nedić, Nešović, Radišić, Gašić, Baošić, Joksimović, Pezo, Tešić and Vovk.)

A 70% ethanol (aq) extract of the rhizome bark of the invasive alien plant species Japanese knotweed (JKRB) with potent (in the range of vitamin C) and stable antioxidant activity was incorporated in 1% w/v into a chitosan biofoil, which was then characterized on a lab-scale. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay confirmed the antioxidant activity of the JKRB biofoil upon contact with the food simulants A, B, C, and D1 (measured half-maximal inhibitory concentrations-IC 50 ) and supported the Folin-Ciocalteu assay result. The migration of the antioxidant marker, (-)-epicatechin, into all food simulants (A, B, C, D1, D2, and E) was quantified using liquid chromatography hyphenated to mass spectrometry (LC-MS). Calculations showed that 1 cm 2 of JKRB biofoil provided antioxidant activity to ~0.5 L of liquid food upon 1 h of contact. The JKRB biofoil demonstrated antimicrobial activity against Gram-positive bacteria. The incorporation of JKRB into the chitosan biofoil resulted in improved tensile strength from 0.75 MPa to 1.81 MPa, while elongation decreased to 28%. JKRB biofoil's lower moisture content compared to chitosan biofoil was attributed to the formation of hydrogen bonds between chitosan biofoil and JKRB compounds, further confirmed with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The JKRB biofoil completely degraded in compost in 11 days. The future upscaled production of JKRB biofoil from biowastes for active packaging may support the fights against plastic waste, food waste, and the invasiveness of Japanese knotweed, while greatly contributing to the so-called 'zero-waste' strategy and the reduction in greenhouse gas emissions.

Flavan-3-ols and proanthocyanidins of invasive alien plants Japanese knotweed ( Fallopia japonica Houtt.), giant knotweed ( Fallopia sachalinensis F. Schmidt) and Bohemian knotweed ( Fal lo pia × bohemica (Chrtek & Chrtkova) J.P. Bailey) were investigated using high performance thin-layer chromatography (HPTLC) coupled to densitometry, image analysis and mass spectrometry (HPTLC-MS/MS). (+)-Catechin, (-)-epicatechin, (-)-epicatechin gallate and procyanidin B2 were found in rhizomes of these three species, and for the first time in Bohemian knotweed. (-)-Epicatechin gallate, procyanidin B1, procyanidin B2 and procyanidin C1 were found in giant knotweed rhizomes for the first time. Rhizomes of Bohemian and giant knotweed have the same chemical profiles of proanthocyanidins with respect to the degree of polymerization and with respect to gallates. Japanese and Bohemian knotweed have equal chromatographic fingerprint profiles with the additional peak not present in giant knotweed. Within the individual species giant knotweed rhizomes and leaves have the most similar fingerprints, while the fingerprints of Japanese and Bohemian knotweed rhizomes have additional peaks not found in leaves. Rhizomes of all three species proved to be a rich source of proanthocyanidins, with the highest content in Japanese and the lowest in Bohemian knotweed (based on the total peak areas). The contents of monomers in Japanese, Bohemian and giant knotweed rhizomes were 2.99 kg/t of dry mass (DM), 1.52 kg/t DM, 2.36 kg/t DM, respectively, while the contents of dimers were 2.81 kg/t DM, 1.09 kg/t DM, 2.17 kg/t DM, respectively. All B-type proanthocyanidins from monomers to decamers (monomers-flavan-3-ols, dimers, trimers, tetramers, pentamers, hexamers, heptamers, octamers, nonamers and decamers) and some of their gallates (monomer gallates, dimer gallates, dimer digallates, trimer gallates, tetramer gallates, pentamer gallates and hexamer gallates) were identified in rhizomes of Bohemian knotweed and giant knotweed. Pentamer gallates, hexamers, hexamer gallates, nonamers and decamers were identified for the first time in this study in Bohemian and giant knotweed rhizomes.

A methodology based on off-line multidimensional thin-layer chromatography was developed for isolation of several secondary metabolites from bark of Japanese knotweed (Fallopia japonica Houtt.) rhizomes. Successive fractionation steps using PLC silica gel and HPTLC silica gel or HPTLC cellulose plates in combination with various developing solvents enabled isolation of (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, procyanidin B1, procyanidin B2, procyanidin B3, proanthocyanidin B dimer gallate, emodin, emodin-8-O-glucoside and emodin-8-O-malonyl-glucoside. Their identity was confirmed by HPTLC, HPTLC-MS n and for most of them also by 1 H NMR and 2D NMR analyses. To the best of our knowledge emodin-8-O-malonyl-glucoside, procyanidins B1 and B2 were for the first time isolated from this plant material. HPTLC and HPTLC-MS n analyses were also performed as support of fractionation/isolation process, leading to first detection of some compounds in bark of Japanese knotweed rhizomes and Japanese knotweed rhizomes in general: procyanidins B1 and B2, methyl derivatives of emodin bianthrone and emodin bianthrone-hexose, resveratrol-malonyl-hexoside and taxifolin derivatives. Characterization of flavan-3-ols and proanthocyanidins was facilitated by post-chromatographic derivatization of the corresponding chromatographic zones with 4-dimethylaminocinnamaldehyde (DMACA) detection reagent., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The antioxidant activities of Japanese knotweed rhizome bark extracts, prepared with eight different solvents or solvent mixtures (water, methanol, 80% methanol (aq) , acetone, 70% acetone (aq) , ethanol, 70% ethanol (aq) , and 90% ethyl acetate (aq) ), were determined using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging assay. Low half maximal inhibitory concentration (IC 50 ) values (2.632-3.720 µg mL -1 ) for all the extracts were in the range of the IC 50 value of the known antioxidant ascorbic acid at t 0 (3.115 µg mL -1 ). Due to the highest extraction yield (~44%), 70% ethanol (aq) was selected for the preparation of the extract for further investigations. The IC 50 value calculated for its antioxidant activity remained stable for at least 14 days, while the IC 50 of ascorbic acid increased over time. The stability study showed that the container material was of great importance for the light-protected storage of the ascorbic acid (aq) solution in a refrigerator. Size exclusion-high-performance liquid chromatography (SEC-HPLC)-UV and reversed phase (RP)-HPLC-UV coupled with multistage mass spectrometry (MS n ) were developed for fractionation of the 70% ethanol (aq) extract and for further compound identification, respectively. In the most potent antioxidant SEC fraction, determined using an on-line post-column SEC-HPLC-DPPH assay, epicatechin, resveratrol malonyl hexoside, and its in-source fragments (resveratrol and resveratrol acetyl hexoside) were tentatively identified by RP-HPLC-MS n . Moreover, epicatechin was additionally confirmed by two orthogonal methods, SEC-HPLC-UV and high-performance thin-layer chromatography (HPTLC) coupled with densitometry. Finally, the latter technique enabled the identification of (-)-epicatechin. (-)-Epicatechin demonstrated potent and stable time-dependent antioxidant activity (IC 50 value ~1.5 µg mL -1 ) for at least 14 days.

Anthraquinones (yellow dyes) were extracted from Japanese knotweed rhizomes with twelve extraction solvents (water; ethanol (aq) (20%, 40%, 60%, 70% and 80%), ethanol, 70% methanol (aq) , methanol, 70% acetone (aq) , acetone and dichloromethane). The obtained sample test solutions (STSs) were analyzed using high-performance thin-layer chromatography (HPTLC) coupled to densitometry and mass spectrometry (HPTLC-MS/MS) on HPTLC silica gel plates. Identical qualitative densitometric profiles (with anthraquinone aglycones and glycosylated anthraquinones) were obtained for STSs in all the solvents except for the STS in dichloromethane, which enabled the most selective extractions of anthraquinone aglycones emodin and physcion. The highest extraction efficiency, evaluated by comparison of the total peak areas in the densitograms of all STSs scanned at 442 nm, was achieved for 70% acetone (aq) . In STS prepared with 70% acetone (aq) , the separation of non-glycosylated and glycosylated anthraquinones was achieved with developing solvents toluene-acetone-formic acid (6:6:1, 3:6:1 and 3:3:1 v / v ) and dichloromethane-acetone-formic acid (1:1:0.1, v / v ). Non-glycosylated anthraquinones were separated only with toluene-acetone-formic acid, among which the best resolution between emodin and physcion gave the ratio 6:6:1 ( v / v ). This solvent and dichloromethane-acetone-formic acid (1:1:0.1, v / v ) enabled the best separation of glycosylated anthraquinones. Four HPTLC-MS/MS methods enabled the identification of emodin and tentative identification of its three glycosylated analogs (emodin-8- O -hexoside, emodin- O -acetyl-hexoside and emodin- O -malonyl-hexoside), while only the HPTLC-MS/MS method with toluene-acetone-formic acid (6:6:1, v / v ) enabled the identification of physcion. Changes of the shapes and the absorption maxima (bathochromic shifts) in the absorption spectra after post-chromatographic derivatization provided additional proof for the detection of physcion and rejection of the presence of chrysophanol in STS.

We developed a simple and robust liquid chromatographic/mass spectrometric method (LC-MS) for the quantitative analysis of 10 sterols from the late part of cholesterol synthesis (zymosterol, dehydrolathosterol, 7-dehydrodesmosterol, desmosterol, zymostenol, lathosterol, FFMAS, TMAS, lanosterol, and dihydrolanosterol) from cultured human hepatocytes in a single chromatographic run using a pentafluorophenyl (PFP) stationary phase. The method also avails on a minimized sample preparation procedure in order to obtain a relatively high sample throughput. The method was validated on 10 sterol standards that were detected in a single chromatographic LC-MS run without derivatization. Our developed method can be used in research or clinical applications for disease-related detection of accumulated cholesterol intermediates. Disorders in the late part of cholesterol synthesis lead to severe malformation in human patients. The developed method enables a simple, sensitive, and fast quantification of sterols, without the need of extended knowledge of the LC-MS technique, and represents a new analytical tool in the rising field of cholesterolomics.

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

The purpose of the study was to investigate the migration of oleamide, a polymer lubricant, and a bioactive compound, from various plastic, marketed containers for food/beverages and medicines into polymer contact liquid. Methanol, food/medicine simulants or real samples were used to extract polymer leachables and extractables. Migrated oleamide into polymer contact liquids was determined by ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS). The concentration of oleamide in the extracts of medicinal and insulin syringes was 7351 ng mL -1 and 21,984 ng mL -1 , respectively. The leachates of intravenous ( i.v. ) infusion bottle, medicinal and insulin syringes contained 17 ng mL -1 , 12 ng mL -1 and 152 ng mL -1 , respectively. Oleamide in the extracts of dummies ranged from 30 to 39 ng mL -1 , while in the leachates of baby bottles, from 12 to 23 ng mL -1 . Leachates of soft drink bottles contained from 6 to 15 ng mL -1 oleamide, milk bottles from 3 to 9 ng mL -1 , liquid yogurt bottles 17 ng mL -1 and water bottles from 11 to 18 ng mL -1 . Bottled real matrices of oil and milk contained oleamide in the range from 217 to 293 ng mL -1 . Moreover, the source of migrated oleamide (e.g., containers, caps, other parts) was identified. Oleamide is listed in the current EU regulations without a specific migration limit. Accordingly, these values are considered of no concern, unless future toxicological studies prove the opposite.

The profile of flavan-3-ols and proanthocyanidins in five different Rosa species (R. canina, R. glutinosa, R. rubiginosa, R. multiflora, and R. spinosissima) was estimated on high performance thin layer chromatography cellulose plates. Differences in flavanol and proanthocyanidin profiles of the extracts were evident, among which Rosa spinosissima stood out with catechin as the only detected flavanol and red zones as indication of anthocyanins. Furthermore, the elution solvent for thin layer chromatography with mass spectrometry analyses of glycosylated flavan-3-ols and proanthocyanidins was optimized, enabling identification of catechin, (epi)catechin hexoside, proanthocyanidin dimer, and proanthocyanidin dimers and trimers hexosides. A total of 15 flavanols and their derivatives were identified using ultra-high-performance liquid chromatography with linear trap quadrupole-Orbitrap mass analyzer and epicatechin, gallocatechin, and proanthocyanidin trimer were identified only using this technique. However, proanthocyanidin trimer trihexoside was identified only by thin-layer chromatography with mass spectrometry. To establish the relationships between the flavanols and proanthocyanidins composition of rose hip and their origin, principal component analysis was performed on the entire set of liquid chromatography/mass spectrometry data. Both principal components' scores plots showed that Rosa spinosissima could be considered as an outlier. Our study demonstrated that flavanol and proanthocyanidin profiles of different rose hips depend on the geographical origin rather than on the cultivar and genotype., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)