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• Automatic selection of embedding dimension in Singular spectrum analysis is achieved. • Singular spectrum analysis yields the most stable and accurate sea level heights among the methods. • Singular spectrum analysis provides a better concentration of spectral power in the periodogram. In order to obtain reliable GNSS-R derived sea level heights (SLHs), it is crucial to extract accurate reflected signals from signal-to-noise ratio (SNR) data. In this study, Quadratic Fitting, Empirical Mode Decomposition (EMD), Ensemble Empirical Mode Decomposition (EEMD), and Singular Spectrum Analysis (SSA) are adopted for extracting the reflected signals from SNR data, which are then analyzed with Lomb Scargle Periodogram (LSP) assisted with tidal harmonic analysis for GNSS-R SLHs. Three continuous GNSS stations including Onsala in Sweden, Friday Harbor in the United States, and Brest in France with tidal ranges of approximately 1 m, 3 m, and 7 m, respectively, were used in the study. The derived SLHs were evaluated against the nearby or co-located tide gauge records. The results reveal that the three proposed algorithms effectively cope with the multi-peaks spectrum problems when using the conventional Quadratic Fitting without a priori reflected height constraint, and SSA can provide the solutions with fewer outliers among the proposed methods with the RMSEs of 6.7 cm, 13.4 cm and 39.6 cm at Onsala, Friday Harbor, and Brest stations, respectively. Without implementing tidal harmonic analysis, SSA is the method capable of acquiring reliable SLHs among the stations, as evidenced by comparing with co-located gauge records, particularly at the Brest station. In summary, SSA not only distinguishes signals across different frequencies, but also orders the signal components according to their eigenvalues, demonstrating the potential to extract the reflected signals from SNR and enhance the stability and accuracy of GNSS-R applications. [ABSTRACT FROM AUTHOR]

• Analysis of geomagnetic field's H time series during quiet geomagnetic condition. • The H time series from high latitude region shows anti-persistent behaviour. • H time series of quiet geomagnetic condition shows multifractal characteristics. • Change in multifractal characteristics with latitude is observed. • The cause of multifractality is identified as long-range correlations. The generation of geomagnetic time series frequently involves intricate spatio-temporal dynamics, wherein nonlinearity and scaling emerge as pivotal mechanisms. The present work investigates the fractal properties of geomagnetic field, and its sources during quiet geomagnetic conditions, by analyzing the horizontal component data of 1 min resolution (H time series) from different latitude regions. Analysis using Auto Correlation Function (ACF), Power spectrum analysis (PSA), Rescaled range analysis (R/S) and Detrended Fluctuation Analysis (DFA) gave indications of the presence of long-range correlations, fractal properties and scaling behaviour of quiet period H time series data. The strong q dependence of generalized Hurst exponent h(q) and scaling exponent Ʈ(q), obtained from the Multifractal Detrended Fluctuation Analysis (MFDFA) method, confirmed the multifractal behaviour of quiet period H time series. The multifractal source analysis of the quiet period H time series with its shuffled and surrogate time series data revealed that, the multifractal characteristics are caused almost entirely by the long-range correlations between small and large fluctuations. The analysis of the latitudinal variations in the multifractal characteristics is also performed as a part of the work, by considering H time series belonging to various latitudes under almost same longitude. The observed decrease in the generalized Hurst exponent values with increase in latitude indicates the change in the multifractal characteristics of the time series with latitude. Also the work revealed that, the H time series from high latitude region shows anti-persistent behaviour, even when the H time series from observatories located at the low and mid latitude regions exhibiting persistent behaviour. The change in the persistence, anti-persistence behaviour can be related to the strength of Earth's magnetic field. [ABSTRACT FROM AUTHOR]

This study successfully synthesized novel phosphors Ca 2 GaTaO 6 : x Dy3+ (CGTO: x Dy3+) and Ca 2 GaTaO 6 :0.06Dy3+, y Sm3+ (CGTO:0.06Dy3+, y Sm3+) using the high temperature solid-phase reaction preparation. The microstructure, optical properties, and energy transfer mechanism of the phosphors were studied through X-ray diffraction (XRD), scanning electron microscope (SEM), photoluminescence (PL) spectra and fluorescence lifetimes. XRD and corresponding refinement results indicate that Dy3+ and Sm3+ ions were effectively doped into the Ca 2 GaTaO 6 (CGTO) lattice. The SEM graphs show that the elements in CGTO:0.06Dy3+, 0.5Sm3+ phosphors are uniformly distributed. PL spectra analysis show the CGTO: x Dy3+ phosphors display two strong emission peaks located at 482 nm for blue emission and 575 nm for yellow emission when excited with 350 nm light. Under uniform conditions, when excited with 365 nm of light, the CGTO:0.06Dy3+, y Sm3+ phosphors emit light that can be tuned with adjustable color coordinates and correlated color temperature (CCT) by incorporating varying proportions of Sm3+ ions. This tunability is achieved through the effective energy migration from Dy3+ to Sm3+ ions within the phosphor material. Furthermore, the emission spectra and weaken lifetimes of the CGTO:0.06Dy3+, y Sm3+ confirm the energy transport between Dy3+ and Sm3+, and the energy transfer efficiency reached to 76 %. At 423 K, the luminescence intensity of CGTO:0.06Dy3+, 0.05Sm3+ phosphor retains 87 % of the intensity observed at 298 K, signifying its excellent thermal durability. Finally, the electroluminescent performance of the CGTO:0.06Dy3+ and CGTO:0.06Dy3+, 0.05Sm3+ phosphors packaged on 365 nm light-emitting diode (LED) chips respectively were studied to investigate the capability applications of the phosphors in white light-emitting diodes (WLEDs) field. The CCT of the packaged LEDs decline from 3396 to 2825 K, indicating CGTO:0.06Dy3+, 0.05Sm3+ phosphor shifts to warmer white light. At a voltage input of 3.4 V and a current of 600 mA, the thermal sensing shows that the WLEDs maintain aptitude for 90 min, showing that the packaged WLEDs can function consistently under elevated temperatures. These studies indicated the phosphors have potential applications in indoor lighting. [ABSTRACT FROM AUTHOR]

Southeastern Turkey perished by the M w 7.8, Kahramanmaras earthquake on February 6, 2023, at 01:17 UT (04:17 LT). The Kahramanmaras-centered event, hit by the break of the East Anatolian Fault Line, is felt in Syria, Egypt, Lebanon, Iraq, and Cyprus on the border of Turkey. Together with Syria, it causes loss of lives and severe damage in 10 cities. This work is dedicated to the people of the region. The study discusses the causality of anomalies by conducting ionospheric anomaly research via the interpolated TEC map obtained from the CODE according to the coordinates of the epicenter of the earthquake (latitude, longitude). The TEC amplitudes are observed by evolving the time-domain TEC map into the frequency-domain with the Fourier transform. The peaks of the amplitudes allow preliminary information for the anomaly days. For the anomaly, the TEC (TECU) boundaries are drawn by the statistical specification. The TEC map outside these boundaries is marked as an anomaly. The causality of abnormalities is tried to be read through the triad of the geomagnetic storm(s) , solar activity , and the earthquake effect. One can find seven anomaly days in the paper. January 30, February 2, 3, 11, 15, 16, and 21 are the anomaly days. The essay probably detects the anomaly before 3 days related to the Southeastern earthquake. • Reads the causality of the earthquake in southeast Turkey (Mw 7.8), through the ionosphere-earth crust relationship. • Notices potential anomalies by presenting the time-domain TEC atlas in the frequency domain with Fourier spectral analysis. • Considering all possible TEC anomaly essentials detect the precursors of the earthquake 3 days before the event day. [ABSTRACT FROM AUTHOR]

Studying the mechanisms of bagasse conversion into syngas is essential to sustain the growing use of biomass in energy economy production. In this work, the precise kinetics of bagasse gasification with various gasification agents was firstly investigated employing in-situ infrared spectra with Coats-Redfern integration, combining qualitative infrared spectroscopy allowed for kinetic analysis, so as to explore how the intermediate species vary in each basic reaction. The results demonstrate that the CO 2 agent reduces the activation energy of nitryl after amino oxidation, making the lignin involved in gasification more easily as well as causing higher gasification efficiency. On the one hand, steam serving as a gasification agent enhances the concentration of hydroxyl groups and produces H 2 -rich syngas. On the other hand, the strong oxidizing hydroxyl group reduces the energy barrier of carbonyl and carboxyl groups in cellulose, which facilitates the gasification process. Furthermore, this study compared the effects of gasification agent (H 2 O or CO 2) on syngas composition, reactor temperature distribution, carbon conversion rate, gasification efficiency, as well as low calorific value, providing essential information for understanding the micro-reaction pathways and pathway regulation during bagasse gasification. • Reducing the activation energy of functional groups are regulated by gasifiers. • The synergistic of gasification agents regulate chemical bond-breaking pathways. • The prospects of producing H 2 from biomass gasification are elucidated. [ABSTRACT FROM AUTHOR]

As a representative local medicinal herb produced in China, Vladimiriae Radix (VR) has been proven to exert hepatoprotective and choleretic effects, with particular therapeutic efficacy in cholestatic liver injury (CLI), as demonstrated by the VR extract (VRE). However, the quality markers (Q-markers) of VRE for the treatment of CLI remain unclear. A new strategy based on the core element of "efficacy" was proposed, using a combination of spectrum-effect relationship, pharmacokinetics, and molecular docking methods to select and confirm Q-markers of VRE. First, the HPLC fingerprinting of 10 batches of VRE was studied, and the in vivo pharmacological index of anti-CLI in rats was determined. The spectrum-effect relationship was utilized as a screening method to identify the Q-markers of VRE. Secondly, Q-markers were used as VRE pharmacokinetic markers to measure their concentrations in normal and CLI rat plasma, and to analyze their disposition. Finally, molecular docking was utilized to predict the potential interaction between the identified Q-markers and crucial targets of CLI. The fingerprints of 10 batches of VRE was established. The in vivo pharmacological evaluation of rats showed that VRE had a significant therapeutic effect on CLI. The spectrum-effect correlation analysis showed that costunolide (COS) and dehydrocostus lactone (DEH) were the Q-markers of VRE anti-CLI. The pharmacokinetic results showed that AUC (0-t) , C max , CL Z/F , and V Z/F of COS and DEH in CLI rats had significant differences (P < 0.01). They were effectively absorbed into the blood plasma of CLI rats, ensuring ideal bioavailability, and confirming their role as Q-markers. Molecular docking results showed that COS, DEH had good affinity with key targets (FXR, CAR, PXR, MAPK, TGR5, NRF2) for CLI treatment (Binding energy < −4.52 kcal mol−1), further verifying the correctness of Q-marker selection. In this study, through the combination of experimental and theoretical approaches from the aspects of pharmacodynamic expression, in vivo process rules, and interaction force prediction, the therapeutic effect of VRE and Q-markers (COS、DEH) were elucidated. Furthermore, a new idea based on the principle of "efficacy" was successfully proposed for screening and evaluating Q-markers. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new fluorine-substituted benzyl triphenylphosphine tetrabromocobaltate(II) was synthesized and characterized. • The FT-IR and Raman spectra analysis were employed to identify the functional groups present in the molecule. • The HOMO-LUMO energy gap explains the interaction of charge transfer in molecules. • Non-linear optical properties were predicted by DFT calculations on the as-prepared crystal. A new organic-inorganic hybrid [4FBzTPP] 2 [CoBr 4 ](1) (4FBzTPP = 4-fluorobenzyltriphenylphosphonium) was synthesized and characterized by X-ray diffraction, DTA-TG measurement, FT-IR and Raman spectroscopies, Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) and UV–vis diffuse reflectance spectrum. [4FBzTPP] 2 [CoBr 4 ] crystallized in monoclinic system with P 2 1 / c space group, consisting of two [4FBzTPP]+ cations and one distorted tetrahedral [CoBr 4 ]2− anion. Powder X-ray diffraction analysis confirmed the bulk phase purity and homogeneity of the material. The UV–vis-DRS result indicated that the energy gap value of the electron transition was 1.60 eV, which was quite distant from the calculated value of 1.64 eV. The material showed fluorescent emission at 389 nm, 414 nm, 448 nm, and 495 nm under the excitation of UV light at 380 nm. Theoretical calculations were performed using the density functional theory method to derive the dipole moment and first hyperpolarizability of the as-synthesized molecule. The first hyperpolarizability value (β tot) was more than 11,600 times higher than those of standard KDP crystals, indicating that [4FBzTPP] 2 [CoBr 4 ] was an excellent material for applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• Flume experiments were conducted to assess the impact of submerged flexible vegetation on regular wave attenuation and beach morphology. • The presence of vegetation prevented further erosion of the beach, resulting in a reduction of 7% to 63% in experiments. • The attenuation caused by vegetation results in the wave breaking point being closer to the shoreline on vegetated sand, leading to shoreline retreat. • A dimensionless equation was developed to characterize the behaviour of the cross-shore beach profile under the protection of flexible vegetation. Coastal protection methods are evolving from hard engineering techniques to natural enhancement approaches. Aquatic vegetation provides an environmentally friendly solution by effectively dissipating waves and resisting erosion. Laboratory flume experiments were conducted to investigate the effect of submerged flexible vegetation on the regular wave attenuation and cross-shore profiles on the artificial plane beach under varying hydraulic conditions. Variations in the waveform, wave spectrum, and wave height were analysed in the vegetation zone. Results show vegetation distorts the waveform and accelerates the attenuation process of the wave energy, and wave height evolution behaves differently from the theoretically obtained attenuation by Mendez and Losada (2004) due to the underestimating vegetation-induced attenuation and neglecting sediment-induced attenuation. Additionally, the formation process of the winter and summer profiles of the vegetated beach was analysed by the screenshots. Regenerated wave breaking becomes more apparent with increasing wave periods. The critical surf similarity parameter of the vegetated beaches was found to be lower than that of a smooth, impermeable slope because of the energy dissipation. Vegetation did not alter the type of the beach profiles, as compared to the final profiles and their characteristic parameters of the unvegetated beaches. Instead, it reduced the erosion depth and brought the eroded area closer to the shoreline. Dimensionless parameters were formulated to characterize the response of the cross-shore beach profile under the shelter of flexible vegetation, and an empirical equation about maximum erosion depth was developed within the scope of the experiment. [ABSTRACT FROM AUTHOR]

Phytochemical investigations of the twig and leaf extracts of Uvaria dac Pierre ex Finet & Gagnep. resulted in the isolation and identification of five new highly oxygenated cyclohexenes, uvaridacols M − Q (1 – 3 , 5 , and 6), and six known compounds (4 and 7 – 11). All new structures were elucidated by spectroscopic methods and HRESITOFMS data. The absolute configuration of 1 , 5 , and 6 was confirmed by single X-ray diffraction analysis with Cu Kα radiation. In contrast, other compounds were established by comparing their specific rotation and ECD spectra with those of known compounds. Some of the isolated compounds with sufficient quantity were evaluated for their α-glucosidase inhibitory activity. Of these, (−)-1,6-desoxypipoxide (10) showed α-glucosidase inhibitory activity with an IC 50 value of 28.6 μM. The in silico molecular docking of active compounds was also studied. Phytochemical investigations of the twig and leaf extracts of Uvaria dac Pierre ex Finet & Gagnep. resulted in the isolation and identification of five new highly oxygenated cyclohexenes and six known compounds. Some of the isolated compounds with sufficient quantity were evaluated for their α-glucosidase inhibitory activity. Of these, (−)-1,6-desoxypipoxide (10) showed α-glucosidase inhibitory activities with an IC 50 value of 28.6 μM. [Display omitted] • Five new oxygenated cyclohexenes were isolated from Uvaria dac. • The absolute configuration of uvaridacol M, P, Q were confirmed by single X-ray diffraction analysis with Cu Kα radiation. • Oxygenated cyclohexenes containing a cinnamoyl moiety, such as uvaridacols N and P first reported here. • 1,6-Desoxypipoxide showed α -glucosidase inhibitory activity. • 1,6-Desoxypipoxide was docked into α -glucosidase (PDB ID: 2QMJ) in silico molecular docking. [ABSTRACT FROM AUTHOR]

Five undescribed meroterpenoids, baosglucidnes A − E (1 – 5), were isolated from the fruiting bodies of Ganoderma lucidum. Among them, baosglucidne B (2) as a racemic mixture was obtained. Chiral HPLC was employed to separate a pair of enantiomers (+)- 2 and (−)- 2. The structures and stereochemical features of these substances were characterized by utilizing spectroscopic data and ECD calculations. Finally, the results of anti-renal fibrosis activity evaluation showed that baosglucidne E (5) could inhibit the expression of collagen I in TGF- β 1-induced rat kidney proximal tubular cells at 20 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four new meroterpenoids, namely nivalones C F (1 – 4), along with a known meroterpenoid, cannabiorcicyclolic acid (5), were isolated from the branches and leaves of Rhododendron nivale. The chemical structures of compounds 1 – 4 were elucidated through comprehensive spectroscopic analyses, including NMR, UV–Vis, IR, ECD spectroscopy, as well as HR-ESI-MS. The isolated compounds were evaluated for their anti-inflammatory and neuroprotective properties. The inhibitory activity of compound 5 against lipopolysaccharide (LPS)-induced nitric oxide (NO) production was initially demonstrated, showcasing an IC 50 value of 21.1 μM. Additionally, both compounds 2 and 5 displayed a notable effect on the viability of H 2 O 2 -damaged SH-SY5Y cells, indicating their significant neuroprotection effects. Four new meroterpenoids 1 – 4 (nivalones C F) and a known meroterpenoid 5 with good anti-inflammatory and neuroprotective effects were isolated from Rhododendron nivale. [Display omitted] [ABSTRACT FROM AUTHOR]

An extensive phytochemical investigation on the rare medicinal plant Semiliquidambar cathayensis (family: Hamamelidaceae) led to the isolation of four new (1 – 4 , named semiliquidacids A–D, respectively) and 25 related known pentacyclic triterpenoids. The new structures with absolute configurations were elucidated by spectroscopic methods, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analysis. Compound 1 represents the first naturally occurring ursane-type triterpenoid featuring an uncommon C-25 formyl group. Compound 4 and oleanolic acid (13) exhibited remarkable inhibitory effects against the ATP-citrate lyase (ACL, an emerging drug target for hyperlipidemia and related metabolic disorders) with IC 50 values of 6.5 and 11.9 μM, respectively. The molecular interaction and binding mode between the bioactive triterpenoids and ACL were elaborated by conducting a molecular docking study. Meanwhile, the chemotaxonomic significance of the isolated triterpenoids has been briefly discussed. [Display omitted] • The rare medicinal plant Semiliquidambar cathayensis was phytochemically investigated. • Four new and twenty-five related known pentacyclic triterpenoids were reported. • Semiliquidacid A is a rare ursane-type triterpenoid featuring a C-25 formyl group. • Semiliquidacid D and oleanolic acid significantly inhibited the ATP-citrate lyase. • A molecular docking study was performed to provide an insight into the binding site. [ABSTRACT FROM AUTHOR]

Diterpenoids occupy an important slot of the natural products diversity space with wide ranges of bioactivities and complex structures, providing potential applications for the development of therapeutics. In this study, we reported four new abietane-type diterpenoids viroxocin B-E (1–4), a new totarane-type diterpenoid viroxocin F (5), and a new sempervirane-type diterpenoid viroxocin G (6) along with four known compounds (7 – 10), isolated and identified from a widely used Traditional Chinese Medicine, Isodon serra (I. serra). Their structures were established by spectroscopic data analysis, experimental and calculated electronic circular dichroism (ECD) data, as well as X-ray diffraction analysis. Compounds 2 , 5 , 7 , 8 and 10 exhibited promising anti-inflammatory activities in lipopolysaccharide (LPS)-induced RAW 267.4 cells, and their inhibition rates on NO production were more than 60% at 10 μM. Compound 7 showed cytotoxicity against human renal cell carcinoma 769P at 20 μM, the inhibition rate was 52.66%. [Display omitted] [ABSTRACT FROM AUTHOR]

Three Stemona alkaloids named stemotuberines A–C (1 – 3) with unique C 17 N frameworks, presumably formed by elimination of the C-11–C-15 lactone ring of the stichoneurine skeleton, were isolated from the roots of Stemona tuberosa. Their structures were elucidated by spectroscopic analysis, X-ray diffraction, and computational methods. Compounds 2 and 3 showed inhibition (IC 50 values of 37.1 and 23.2 μM, respectively) against LPS-induced nitric oxide production in RAW 264.7 cells. In addition, concern was expressed about the reported plant origin (S. sessilifolia) of the recently described alkaloids tuberostemonols O–R (4–7), which should be S. tuberosa. NMR calculations indicated structural misassignment of these compounds except for 6. Isolation of tuberostemonol P (5) from our material of S. tuberosa allowed for a close examination of the spectroscopic data leading to the revised structure 5a. Tuberostemonol R (7) was found to have identical 1H and 13C NMR data to the well-known alkaloid croomine, and therefore its structure including relative stereochemistry must be revised as 7a. [Display omitted] • Three previously undescribed Stemona alkaloids were isolated from Stemona tuberosa. • Compounds 1 – 3 possess unprecedented C 17 N skeletons. • Nitric oxide inhibitory activities of isolated compounds were evaluated. • Putative structures of tuberostemonols P and R were revised. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the EtOAc soluble fraction from leaves of Trichilia dregeana Sond. (Meliaceae) afforded naturally rare four new pentacyclic triterpenoids (1 – 4), together with five known pentacyclic analogs (5 – 8 , and 11) and two steroids (9 and 10). Their structures were elucidated by extensive spectroscopic techniques such as 1D and 2D NMR and HRESIMS data analyses. The absolute configuration of 1 was determined by using the single-crystal X-ray diffraction analysis. The nitric oxide (NO) production inhibitory assay indicated that the EtOAc fraction as well as 4 and 7 inhibited the NO production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with the IC 50 values of 83.53 μg/mL and 81.31 and 85.71 μM, respectively. Compounds 1 – 4 are rare 19(10 → 9) abeo -euphane-type triterpenoids bearing a 3,10-ether bridge. To the best of our knowledge, this study is the first isolation of triterpenoids with the 3,10-ether bridge in their skeleton from the genus Trichilia , providing new insights into the chemodiversity of the terpenoids in T. dregeana. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper proposes an experimental approach to measure contact forces in a two-dimensional system composed of cylindrical particles using the Virtual Fields Method (VFM). This identification method relies on the knowledge of the strain distribution in the particles forming the discrete medium. Synthetic strain data provided by a finite element model (with added noise) were first used as input data for the identification procedure. It is shown that if the mechanical response of the constitutive material is known, the contact forces applied to a particle can be identified, since they are proportional to a weighted average of the strain components, the weights being the virtual strain components. Various strategies were tested to propose kinematically admissible fields for the virtual displacement. Identification technique robustness was studied with respect to various sources of error, such as noise in the strain field, missing data along the boundaries, and a possible spurious shift between real and virtual fields. An experimental application was then performed on a three-particle system subjected to confined compression by processing strain maps obtained using Localized Spectrum Analysis (LSA) for each particle. In addition to the VFM equations, particle equilibrium and Newton's third law of motion were taken into account to propose a relevant strategy for processing the experimental data. The results open up prospects for applications to granular materials composed of numerous particles. • The Virtual Fields Method is used to identify contact forces in a 2D discrete medium. • Four strategies are compared to select the most relevant virtual displacements. • Identification is robust with respect to noise and missing data along particle boundary. • Experimental strain maps are obtained by Localized Spectrum Analysis on a three-particle system. • Particle equilibrium and Newton's third law of motion are also taken into account for processing the experimental data. [ABSTRACT FROM AUTHOR]

This article explores the influence and applications of Artificial Intelligence (AI) in analytical chemistry, highlighting its potential to revolutionize the analysis of complex data sets and the development of innovative analytical methods. Additionally, it discusses the role of AI in interpreting large-scale data and optimizing experimental processes. AI has been fundamental in managing heterogeneous data and in advanced analysis of complex spectra in areas such as spectroscopy and chromatography. The article also examines the historical development of AI in chemistry, its current challenges, including the interpretation of AI models and the integration of large volumes of data. Finally, it forecasts future trends and the potential impact of AI on analytical chemistry, emphasizing the need for ethical and secure approaches in the use of AI. [Display omitted] • AI revolutionizes data analysis in analytical chemistry. • Advanced AI aids complex spectroscopy and chromatography interpretation. • AI in chromatography enhances compound identification and quantification. • Machine learning predicts properties, enhancing drug and material discovery. • Explainable AI models improve interpretability in analytical chemistry. [ABSTRACT FROM AUTHOR]

• Oxidation and Maillard-like reaction together cause krill oil color changes. • UV–vis spectroscopy is more suitable for quantifying color changes of krill oil. • α-Dicarbonyl compounds were formed during storage of krill oil. • Hydrophilic pyrroles associated with PEs was detected in krill oil. Antarctic krill oil (AKO) is reddish-orange in color but undergoes changes during storage. To investigate the color deterioration and potential mechanisms involved, the changes in color, endogenous components (astaxanthin, fatty acids, and phospholipids), and reaction products (aldehydes, α-dicarbonyl compounds, and pyrroles) of AKO upon storage were determined. Although the visual color of AKO tended to darken upon storage, the colorimetric analysis and ultraviolet–visible spectrum analysis both indicated a fading in red and yellow due to the oxidative degradation of astaxanthin. During storage of AKO, lipid oxidation led to the formation of carbonyl compounds such as aldehydes and α-dicarbonyls. In addition, phosphatidylethanolamines (PEs) exhibited a faster loss rate than phosphatidylcholines. Moreover, hydrophobic pyrroles, the Maillard-like reaction products associated with primary amine groups in PEs accumulated. Therefore, it is suggested that the Maillard-like reaction between PEs and carbonyl compounds formed by lipid oxidation contributed to color darkening of AKO during storage. [ABSTRACT FROM AUTHOR]

Stalagmites offer nearly continuous records of past climate in continental settings at high temporal resolution. The climatic records preserved in stalagmites are commonly investigated by examining compositional characteristics such as mineralogy, organic content, and lamination patterns. These proxies provide valuable insights into the environmental conditions during stalagmite formation. However, the methods used to obtain information about these proxies are relatively destructive. This study uses hyperspectral imaging, a non-contact technique, to identify mineral composition, organic matter content, and laminations in stalagmites. It is the first wide spectrum imaging analysis in speleothem research, using both visible–near infrared and shortwave infrared wavelengths. Results obtained from hyperspectral imaging were compared by point spectral analysis using an ASD spectroradiometer and a grayscale profile along the growth axis of a stalagmite. Petrographic observation of thin sections and X-ray diffraction (XRD) analyses on selected stalagmite layers were performed to cross-validate the hyperspectral data. A travertine sample was also used to replicate the method on calcite. To automate mineral identification, a machine learning algorithm was developed to map spatial distribution and quantify relative proportions of minerals across the sample. Our findings are in good agreement with traditionally used methods for mineral identification, i.e. XRD and petrography, aiding in the interpretation of paleoclimate proxies, and offer a spatial guide for U–Th dating analyses. It also provides insight for future investigations of stalagmites using hyperspectral data and classification through machine learning algorithms. [ABSTRACT FROM AUTHOR]

Yataprasen is a topical Thai herbal remedy for the treatment of musculoskeletal pain and is included in Kumpe Thart Phra Narai, the first Thai textbook of traditional medicine. The herbal preparation is made from a hydroethanolic extract of a mixture of 13 medicinal plants, of which Putranjiva roxburghii Wall. leaves are the major ingredient. In this study, we investigated the underlying mechanism of action for the anti-inflammatory effects of the Yataprasen remedy, its main ingredients, and the phytochemicals isolated from P. roxburghii leaves. The anti-inflammatory effects of the Yataprasen remedy, along with its main ingredients, including the leaves of Baliospermum solanifolium (Burm.) Suresh, Melia azedarach L., P. roxburghii , Senna siamea (Lam.) Irwin & Barneby, and Tamarindus indica L. were determined by measuring prostaglandin E 2 (PGE 2) secretion, nitric oxide (NO) production, and the synthesis of inflammatory biomarkers in lipopolysaccharide (LPS)-treated RAW264.7 macrophage cells. The active ingredients of the P. roxburghii leaves were separated by chromatography and spectroscopic measurements were used to identify their chemical structures. Ethanol extracts of the Yataprasen remedy and some of its ingredients significantly suppressed LPS-induced PGE 2 secretion and NO production in a dose-dependent manner. Treatment of RAW264.7 cells with ethanolic extracts of the Yataprasen remedy (50 μg/mL) significantly inhibited LPS-induced mRNA expression of TNF-α, COX-2, iNOS, and NF-κB. Among the plant ingredient extracts, P. roxburghii leaf extract exhibited the highest inhibitory effects on LPS-induced TNF-α and iNOS expression. Moreover, T. indica leaf extract showed the highest activity on the inhibition of LPS-induced COX-2 and NF-κB expression. Putraflavone, podocarpusflavone A, and amentoflavone were isolated biflavonoids from P. roxburghii leaf extract and showed the inhibitory effects on LPS-induced PGE 2 secretion and NO synthesis in RAW264.7 cells. Of the isolated biflavonoids, amentoflavone exhibited the strongest anti-inflammatory activity by inhibiting the expression of TNF-α, COX-2, and iNOS. The results support reported the anti-inflammatory effects of the Yataprasen remedy, which are associated with the downregulation of proinflammatory mediators. P. roxburghii , along with its biflavonoids, are the impact components that contribute to the anti-inflammatory effects of the herbal remedy. [Display omitted] • Yataprasen suppressed COX-2 expression, resulting in a reduction of PGE 2 secretion. • Yataprasen suppressed iNOS expression, resulting in a reduction of NO production. • Yataprasen inhibited TNF-α synthesis in RAW264.7 macrophages. • Among ingredients, P. roxburghii extract showed the highest anti-inflammatory effect. • Among bioflavonoids, amentoflavone showed the strongest anti-inflammatory effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel super broadband NIR phosphor is achieved by doping Yb3+ in Li 2 MgZrO 4 : Cr3+. • The maximum FWHM of the Cr3+/Yb3+ co-doped LMZ phosphor is 270 nm. • The thermal stability of the phosphors was improved with Yb3+ co-doping. • The potential applications in the field of NIR vascular visualization. The discovery of high thermal stability, broad-band near-infrared (NIR) fluorescent phosphors holds significant potential in applications such as non-destructive testing, promoting plant growth, and night vision devices. In this study, a novel broad-band NIR phosphors Li 2 MgZrO 4 (LMZ): 1.0 %Cr3+, y%Yb3+ were synthesized via a high-temperature solid-state reaction method, with the optimal doping concentration found to be y = 1.5. These phosphors exhibited broad NIR emission in the range of 700–1050 nm by effective energy transfer from Cr3+ to Yb3+. The maximum full width at half maximum (FWHM) of the Cr3+/Yb3+ co-doped LMZ phosphor is 270 nm. The thermal stability of the phosphors was improved with Yb3+ co-doping. Additionally, energy transfer from Cr3+ to Yb3+ was confirmed through luminescence spectra and lifetime analysis. Finally, NIR pc-LED devices composed of a 460 nm ultraviolet chip and LMZ: 1.0 %Cr3+, 1.5 %Yb3+ phosphors were fabricated, offering a highly promising source of invisible light. These results demonstrate the wide-ranging potential applications of this novel, high thermal stability, and ultra-broad NIR emitting fluorescent phosphor. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism of colour superposition simulation was utlized to quantitatively demonstrate the colour change of 'chameleon' amber. • GC-MS and HPLC-FL were utilized to examine the organic components of 'chameleon' ambers to confirm the existence of fluorescent substances. • Benzo[a]anthracene with yellowish-green fluorescence is responsible for the bluish green fluoresernce of 'chameleon' amber. One special variety of Burmese amber is "chameleon" amber, named for the bluish-green colour that appears to float on its surface. This material is found in the famous Tengchong market in Yunnan Province, China's largest Burmese amber market. Its bodycolour ranges from golden brown to brownish-red or even red. When exposed to sunlight or strong white light against a black background, its surface shows a uniform green colour. This research presents the gemological properties, spectral characteristics and organic components of Burmese 'chameleon' amber. Three-dimensional (3D) fluorescence spectra showed that Burmese 'chameleon' amber had fluorescence centres near 433, 465 and 470 nm, and the excitation wavelengths of the fluorescence centres of Burmese 'chameleon' amber were shifted from the ultraviolet region (380 ± 10 nm) to the visible region (410 ± 10 nm), with the emission wavelengths concentrated at the bluish-green region. Through the colour simulation and superimposition, the phenomenon of floating bluish-green fluorescence colour of Burmese 'chameleon' amber is not only derived from bluish-green fluorescence centres, but also enhanced by the mixture of surface fluorescence and its bodycolour. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC–MS) analysis demonstrated the variety of aromatic compounds in Burmese 'chameleon' amber was related to geological process and the presence of fluorescence components. The high-performance liquid chromatography-fluorescence detector obtained some fluorescent aromatics, particularly benzo[a]anthracene with yellowish-green fluorescence, which is responsible for the fluorescence characteristics of Burmese 'chameleon' amber. [ABSTRACT FROM AUTHOR]

Vortex beams carrying orbital angular momentum (OAM) modes offer a compelling avenue for increasing optical communication capacity. Despite significant efforts in OAM mode (de)multiplexing, challenges persist in signal demodulation and noise monitoring of multiplexed channels. This challenge largely stems from the absence of efficient feature extraction methods capable of analyzing the OAM spectrum, which delineates mode components and intensity weights. Herein, we introduce a novel strategy for OAM mode spectrum analysis using a residual neural network incorporating interference techniques. By introducing interference between target vortex beams and a spherical wave, resulting in the mapping of OAM distributions onto the stripe features observed in the interferogram. To effectively extract spectrum details from these interferograms, we construct a residual neural network exhibiting high feature processing capabilities, which enables precise analysis of intricate OAM mode spectrum. We demonstrate the effectiveness of this OAM spectrum analysis by obtaining the intensity weights for 15 superimposed modes ranging from −10 to +10, achieving a mean-square-error of 2.3 × 10−4. To validate its practicality, we showcase an 80-channel three-dimensional multiplexing communication system including five OAM modes, two polarizations, and eight wavelengths. The 4 Tbit/s quadrature-phase-shift-keying signals are successfully demodulated with a bit-error rate below 3.34 × 10−6. Additionally, the measured optical signal-to-noise ratio reaches 11.5 dB, indicating the potential applications of this OAM spectrum analysis strategy in signal demodulation and noise monitoring. • A novel strategy for OAM mode spectrum analysis was investigated for signal demodulation and noise monitoring. • The MSE for spectral analysis of 15 superimposed modes in the mode range −10∼+10 was 2.3 × 10−4. • The QPSK signals were demodulated with a BER below 3.34 × 10−6, and the measured OSNR reached 11.5 dB. [ABSTRACT FROM AUTHOR]

[Display omitted] • An azo-Schiff base (ASB) chemosensor was synthesized from salicylaldehyde and N, N-dimethyl-4,4′-azodianiline. • ASB exhibits turn-on fluorescence toward Al3+ due to the Al3+-promoted hydrolysis of imine bonds. • ASB can be used for qualitative and quantitative Al3+ sensing in three antacid tablets. • ASB can be applied to cell imaging of Al3+ in breast cancer cell MCF-7. The azo-Schiff base (ASB) chemosensor was designed and synthesized by the reaction of salicylaldehyde and N, N-dimethyl-4,4′-azodianiline. The ASB sensor can be used to detect Al3+ in antacid tablets and cell imaging applications. After adding Al3+ ions, the ASB sensor exhibits turn-on fluorescence performance because of the Al3+-promoted hydrolysis of the imine bond. The Al3+-promoted hydrolysis of the imine bond has been evidenced by FTIR, 1H NMR, and 13C NMR spectra analysis. The ASB sensor displayed a selective and sensitive recognition of Al3+ by turn-on fluorescence with the detection limit of 1.53 × 10−7 M, and a binding constant of 2.36 × 104 M−1 in an aqueous HEPES buffer/DMSO solution (2/8 v/v). The ASB sensor can be applied to the qualitative and quantitative detection of Al3+ in three antacid tablets (Gelusil, Macgel, Swellin). Besides, the ASB sensor shows low cell toxicity and good cell permeability. The cell-imaging test indicates that the ASB probe can detect Al3+ ions in breast cancer cell MCF-7 under optical fluorescence microscopy. [ABSTRACT FROM AUTHOR]

The hadal Mariana Trench remains poorly understood. In December 2016, an array of high-resolution temperature loggers, attached to the ocean bottom seismometers (OBSs), was deployed from 1665 to 7520 m for two weeks across the Challenger Deep of the Southern Mariana Trench. The temperature variance spectrum reveals that the bottom water is mildly turbulent and it is mainly modulated by the semidiurnal internal tides. At the second deepest observation station (depth of 7015 m), the viscous subrange is resolved in the high-frequency spectrum. Applying the proposed method with Taylor's frozen field hypothesis and Kraichnan theoretical spectrum analysis, it is revealed that turbulent dissipation rate ɛ is 7. 8 × 1 0 − 10 m 2 / s 3 and flow speed U is 8.9 mm/s. Dissipation rates ɛ of all stations vary between 5. 9 × 1 0 − 11 and 1. 4 × 1 0 − 9 m 2 / s 3 , with the northern region of Challenger Deep experiencing stronger energy dissipation than the southern one. The vertical distribution of dissipation rate ɛ shows that it decreases with increasing depth from 1000 to 6000 m, but then increases to around 8000 m, which is consistent with previous observations and numerical simulations. The available turbulent mixing data indicates that the energy dissipation is vertically distributed in a distinct multilayer structure in the deep ocean of Challenger Deep, which is proposed to link to the intrusion of water mass in the deep Mariana trench. • The precise bottom temperature variance across the Challenger Deep was measured. • The bottom water is mildly turbulent with the theoretical spectra analysis. • The deep mixing is behaved in a multilayer structure, likely driven by intrusion. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the extract of endophytic fungus Tolypocladium sp. SHJJ1 resulted in the identification of a pair of previously undescribed pyridoxatin atropisomers [ 1 ( M / P )] and three new indole diterpenoids (3 – 5), together with a pair of known pyridoxatin atropisomers [ 2 ( M / P )] and ten known indole diterpenoids (6 –1 5). Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and X - ray diffraction. Among the undescribed natural products, [ 1 ( M / P )] that two rapidly interconverting atropisomers are the third example to report in the pyridoxatin atropisomers. Except for compounds 1 ( M / P ) and 2 ( M / P ), all other compounds were tested for their cytotoxicity using HepG2, A549, and MCF-7 human cell lines. Compound 9 displayed moderate cytotoxicity against the HepG2, A549, and MCF-7 cell lines with IC 50 values of 32.39 ± 1.48 μM, 26.06 ± 1.14 μM, and 31.44 ± 1.94 μM, respectively, which was similar to the positive drug cisplatin (with IC 50 values of 32.55 ± 1.76 μM, 18.40 ± 1.43 μM, and 27.31 ± 1.22 μM, respectively). [Display omitted] [ABSTRACT FROM AUTHOR]

Ficus altissima , also known as lofty fig, is a monoecious plant from the Moraceae family commonly found in southern China. In this study, we isolated and identified one new isoflavone (1), three new hydroxycoumaronochromones (2a , 2b and 3a) and 12 known compounds from the fruits of F. altissima. Their chemical structures were determined using spectroscopic analysis methods. We also tested all the isolated compounds for their anti-proliferative activities against eight human tumour cell lines (A-549, AGS, K562, K562/ADR, HepG2, HeLa, SPC-A-1 and CNE2) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Our experiments showed that compound 6 exhibited obvious anti-proliferative activity against the K562 cell line with an IC 50 value of 1.55 μM. Additionally, compounds 8 and 9 showed significant anti-proliferative activities against the AGS and K562 cell lines, respectively. Moreover, compound 6 induced apoptosis in K562 cells through the caspase family signalling pathway. [Display omitted] • Four new isoflavones were isolated from the fruits of Ficus altissima. • Compound 6 showed obvious anti-proliferative effect against K562 cell line. • Compounds 8 and 9 showed anti-proliferative effects against AGS and K562 cells. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the buds of edible medicinal plant, Eugenia carvophyllata , led to the discovery of seven new compounds, caryophones A–G (1 – 7), along with two biogenetically-related known ones, 2-methoxy-7-methyl-1,4-naphthalenedione (8) and eugenol (9). Compounds 1 – 3 represent the first examples of C-5–C-1′ connected naphthoquinone-monoterpene adducts with a new carbon skeleton. Compounds 4 – 7 are a class of novel neolignans with unusual linkage patterns, in which the C-9 position of one phenylpropene unit coupled with the aromatic core of another phenylpropene unit. The chemical structures of the new compounds were determined based on extensive spectroscopic analysis, X-ray diffraction crystallography, and quantum-chemical calculation. Among the isolates, compounds (−)- 2 , 3 , 6 , and 9 showed significant in vitro inhibitory activities against respiratory syncytial virus (RSV)-induced nitric oxide (NO) production in RAW264.7 cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Eleven new highly oxygenated eremophilane-type sesquiterpenoids were isolated from the whole plant of Synotis solidaginea , including two pairs of C-8 S / R epimers. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configurations of 1 and 9 were confirmed by single-crystal X-ray crystallography using Cu K α radiation. All the isolates were tested for the inhibition of LPS-stimulated NO production in macrophage-like mouse monocytic leukemia RAW264.7 cells. Compound 1 exhibited weak inhibitory effects with an IC 50 of 71.2 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four new monomeric sorbicillinoids, trichillinoids A − D (1 – 4), along with two known dimeric sorbicillinoids (5 and 6), and five known monomeric sorbicillinoids (7 – 11), were obtained from the marine-fish-derived fungus Trichoderma sp. G13. They were structurally characterized on the basis of comprehensive spectroscopic investigations (NMR, HRESIMS, and ECD). Compounds 1 – 4 displayed moderate anti-inflammatory activities, according to inhibiting the production of NO in RAW264.7 cells activated with IC 50 values ranging from 14 to 20 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Five undescribed eremophilane-type sesquiterpenes, remophilanetriols E -I (1 – 5), along with seven known compounds (6 – 12) were isolated from the fresh roots of Rehmannia glutinosa. Their structures were characterized by extensive spectroscopic data analysis and their absolute configurations were determined by comparing their calculated electronic circular dichroism (ECD) spectra and experimental ECD spectra. The anti-pulmonary fibrosis activities of all compounds were evaluated in vitro by MTT methods, and compounds 2 , 8 , 10 , and 12 exhibited excellent anti-pulmonary fibrosis activities. In addition, compound 2 can reduce the levels of ROS and apoptosis in TGF-β1-induced BEAS-2B cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Six previously undescribed diterpenoid glucosides, along with four known compounds, were isolated from the aerial parts of Sigesbeckia glabrescens. The structures and absolute configurations of undescribed compounds were elucidated using extensive spectroscopic techniques, ECD calculations and chemical methods. Compounds 1 and 8 exhibited anti-inflammatory activity against LPS-induced NO production in RAW 264.7 macrophages, with compound 8 demonstrating significant inhibitory activity compared to positive control minocycline, boasting an IC 50 value at 14.20 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new xanthone derivatives irpexols A-C (1 – 3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1 – 3) share a de-aromatic and highly‑oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1 – 8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC 50 values ranging from 24.83 to 45.46 μM, while the IC 50 values of the positive control adriamycin was ranging from 1.11 to 1.44 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four previously undescribed isoprenoid flavonoids (2 – 5) were isolated from Sophora davidii , along with five known analogues. The structures of the compounds were established through comprehensive analysis of spectroscopic data, including HRESIMS, 1D and 2D NMR, and absolute configurations determined by theoretical calculations, including ECD and NMR calculation. The cytotoxic effects of the isolated compounds on human HT29 colon cancer cells were evaluated using the MTT assay, compound 1 exhibited cytotoxicity against human HT29 colon cancer cells with an IC 50 value of 8.39 ± 0.09 μM. Studies conducted with compound 1 in HT29 cells demonstrated that it may induce apoptosis and autophagy in HT29 by promoting the phosphorylation of P38 MAPK and inhibiting the phosphorylation of Erk MAPK. Four previously undescribed isoprenoid flavonoids were isolated from Sophora davidii. Compound 1 showed significant inhibitory activity against human HT29 colon cancer cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Four undescribed compounds including three harzianic acids (1 , 3 and 4) and one oxazolidinone (2), along with three known ones (5 – 7) were isolated from the solid fermented product of endophytic fungus Ilyonectria sp., their structures were elucidated as 1-amino-harzianic acid (1), ilyonectria-oxazolidinone (2),10′-nor- isoharzianic acid (3), isohomoharzianic acid (4), harzianic acid (5), isoharzianic acid (6), homoharzianic acid (7) by means of detailed chemical evidences and spectroscopic data analysis. All the compounds were evaluated for cytotoxicity against SMMC-7721 human cancer cell lines by MTS assay. Among the seven tested compounds, 1-amino-harzianic acid (1) demonstrated well cytotoxic activity against SMMC-7721 with IC 50 value of 26.84 μM. The results of molecular docking indicated that compound exhibited moderate anti-tumor activity may through binding to apoptosis related proteins. [Display omitted] [ABSTRACT FROM AUTHOR]

Five new B- seco -limonoids, namely toonanoronoids A-E (1 – 5), in conjunction with three previously reported compounds, were isolated from the EtOAc extract of the twigs and leaves of Toona ciliata var. yunnanensis. Their structures were elucidated through comprehensive spectroscopic and X-ray crystallographic analysis. The cytotoxic activities of new compounds against five human tumor cell lines (HL-60, SMMC-7721, A549, MCF-7, and SW480) were screened, Compounds 4 and 5 exerted inhibition toward two tumor cell lines (HL-60, SW-480) with IC 50 values between 1.7 and 5.9 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four undescribed ginkgolides, including two rare sesquiterpene ginkgolides (compounds 1 and 2) and two diterpenoid ginkgolides (compounds 3 and 4) , were isolated from Ginkgo biloba L. The structures of these four ginkgolides were identified based on extensive spectroscopic analysis, DP4+ probability analysis and X-ray diffraction. Compounds 1 and 2 exhibited excellent antiplatelet aggregation activities with IC 50 values of 1.20 ± 0.25 and 4.11 ± 0.34 μM, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new indole alkaloid derivatives, fissindoalkas A-C (1 – 3) together with one known biogenetically related polysubstituted indole alkaloid (4) were isolated from the roots of Fissistigma oldhamii (Hemsl.) Merr. The structures of compounds 1 – 4 were elucidated using comprehensive spectroscopic methods. The inhibitory activities of compounds 1 – 4 against nitric oxide (NO) production induced by lipopolysaccharide (LPS) were evaluated in vitro using mouse macrophage RAW264.7 cells. Compounds 2 and 3 showed potent inhibitory activities on NO production with IC 50 values of 2.52 ± 0.18 and 2.33 ± 0.16 μM. These results indicate that the discovery of indole alkaloid derivatives, from the roots of F. oldhamii , which show significant anti-inflammatory properties, could be of great importance to the research and for the development of novel natural anti-inflammatory agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Three undescribed sesquiterpenes, designed as pichinenoid A-C (1 – 3), along with nine known ones (4 – 12) were isolated from the stems and leaves of Picrasma chinensis. The new isolates including their absolute configurations were elucidated based on extensive spectroscopic methods, single crystal X-ray diffraction, and electronic circular dichroism (ECD) experiments, as well as comparison with literature data. Structurally, compounds 1 and 2 are descending sesquiterpenes, while pichinenoid C (3) is a rare sesquiterpene bearing a 2-methylenebut-3-enoic acid moiety at the C-6 side chain. All the isolated compounds were tested for their neuroprotective effects against the H 2 O 2 -induced damage on human neuroblastoma SH-SY5Y cells, and most of them showed moderate neuroprotective activity. Especially, compounds 1 , 3 – 5 , and 7 showed a potent neuroprotective effect at 25 or 50 μM. Moreover, the neuroprotective effects of compounds 1 and 4 were tested on a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mouse model. Results of western blot and immunofluorescence indicated that compound 4 significantly counteract the toxicity of MPTP, and reversed the expression of tyrosine hydroxylase (TH) in substantia nigra (SN) and striatum (ST) of the mouse brain. Interestingly, western blot data suggested compound 4 also enhanced B-cell lymphoma-2 (Bcl-2) and heme oxygenase 1 (HO-1) expressions in the brain tissues from MPTP damaged mouse. [Display omitted] [ABSTRACT FROM AUTHOR]

Five new compounds were identified from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, involving UV, IR, NMR spectrum and HRESIMS analyses. The absolute configuration of compound 2 was proved by comparing their experimental and calculated ECD spectrum. The vitro bioactive assay of all compounds suggested that compound 1 , 3 , 4 , 5 and 6 may have potential anti-asthmatic activities. five undescribed compounds were isolated from the stems of E. equisetina and assessed for its antiasthma activities. [Display omitted] • Five compounds were isolated from the stems of E. equisetina. • Their structures were elucidated by NMR and mass spectrometry. • The absolute configurations were deduced by interpretation of ECD. • The antiasthma activities of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

Nine metabolites, including three undescribed alkaloids pyripyropenes V W (1 – 2), penicioxa A (4), two previously reported pyripyropene A (3), oxaline (5), three grisephenone-type xanthone derivatives (6 – 8), and a diphenyl ether derivative 4-chloro-7,4′-dihydroxy-5,2′-dimethoxy-2-methylformate-6′-methybenzophone (9), were isolated from cultures of the mangrove-derived fungus Penicillium robsamsonii HNNU0006. Their structures were determined by spectroscopic analysis, ECD calculations, together with DP4+ probability analysis. Furthermore, all the isolated compounds were tested for cytotoxicity and anti-phytopathogenic fungal activities. Compounds 6 – 8 showed moderate cytotoxicity against tumor cell lines A549, with IC 50 values ranging from 5.68 ± 0.21 to 9.71 ± 0.34 μg/mL, respectively. [Display omitted] • Three undescribed alkaloids including a 7/6/6/6-fused pyripyropene-type structure were isolated from P. robsamsonii HNNU0006. • ECD calculations and DP4+ probability analysis were employed to define the absolute configuration of new alkaloids. • The in vitro cytotoxicity and anti-phytopathogenic fungal activities of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

Michelia champaca L. (Magnoliaceae) was cultivated in large scale for flowers as cosmetic raw materials, whereas the value of its leaves remains to be discovered. Our chemical study on the leaves yielded four new flavonol diglycosides, champaflavosides A–D (1 – 4), together with twenty-three known flavonoid glycosides (5 – 27). Their structures were determined by spectroscopic and chemical methods. Compounds 5 – 21 and 23 – 27 were not previously reported from the genus Michelia , and kaempferol 3- O -rutinoside (22) was obtained from this species for the first time. All the compounds were evaluated for antioxidant activity by four in vitro assays. Compounds 3 – 12 and 20 showed more potent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than l -ascorbic acid (l -AA). Compounds 2 – 23 , 25 , and 27 exhibited 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activity superior to l -AA. The ferric reducing antioxidant powers (FRAP) of compounds 2 – 13 , 17 , and 19 were higher than l -AA. Further, eighteen compounds demonstrated cellular reactive oxygen species (ROS) scavenging activity, of which champaflavoside D (4), rhamnetin 3- O -neohesperidoside (8), quercetin 3- O -(6- O - E - p -coumaroyl)-neohesperidoside (9), and liquiritin (27) were more potent than curcumin. The results revealed that the renewable leaves of M. champaca are a rich source of flavonoids and antioxidants. [Display omitted] • Michelia champaca has been widely cultivated for flowers as cosmetic raw materials. • The chemical constituents other than volatile oil in the leaves remain unknown. • Four new and 23 known flavonoid glycosides were isolated from the leaves. • Our research results revealed that the leaves are a rich source of antioxidants. [ABSTRACT FROM AUTHOR]

Seven new triterpenoids, named Adeterpenoids A-G (1 – 7) and eight known compounds (8 – 15), were isolated from 70% ethanol extract of the roots of Adenophora tetraphylla (Thub.) Fisch. The compounds from it were separated by column chromatography techniques such as silica gel, ODS, and preparative liquid chromatography. Their structures were clarified based on extensive spectral analysis (1D, 2D-NMR, HR-ESI-MS, IR, UV, and CD) and comparison with the literature. At the same time, all compounds were evaluated for their cytotoxic activity against the LN229 (human glioma cell line). The results showed that compounds 2 , 5 , 6 , 13, and 14 had a significant inhibitory effect on LN229 cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Falonolide A (1) and B (2), two novel polyyne hybrid phthalides resulting from unprecedented carbon skeleton polymerized by Z -ligustilide and falcarindiol, along with six new related phthalides (3 – 8), were isolated from Ligusticum chuanxiong Hort. Their structures were elucidated by spectroscopic analysis, computer-assisted structure elucidation (CASE) analysis, DP4+ probability analysis and electronic circular dichroism (ECD) calculations. A plausible biosynthetic pathway for 1 – 8 was proposed, and the production mechanism of 2 was revealed by density functional theory (DFT) method. Compounds 4 and 6 exhibited significant vasodilatory activity with EC 50 of 8.00 ± 0.86 and 6.92 ± 1.02 μM, respectively. Compound 4 also displayed significant inhibitory effect of NO production with EC 50 value of 8.82 ± 0.30 μM. Based on the established compounds library, structure-activity relationship analysis of phthalides was explored to provide insights into the drug development of vasodilators and anti-flammatory [Display omitted] • Unprecedented polyyne hybrid skeletons formed by Alder-Rickert reaction discovered in Ligusticum chuanxiong Hort. • Compounds 4 and 6 exhibited significant vasodilatory and anti-inflammatory activities. • Structural-activity analysis of phthalides informed vasodilator and anti-inflammatory drug design. [ABSTRACT FROM AUTHOR]

Two previously undescribed cholestanol saponins, parpetiosides F − G (1 – 2), and six known analogs (3 – 8) were isolated from the rhizomes of Paris fargesii var. petiolata. Their structures were elucidated by extensive spectroscopic data analysis and chemical methods. Compound 1 was a rare 6/6/6/5/5 fused-rings cholestanol saponin with disaccharide moiety linked at C-26 of aglycone which was hardly seen in genus Paris. All of these compounds were discovered in this plant for the first time. In addition, the cytotoxicities of saponins (1 – 8) against three human cancer cell lines (U87, HepG2 and SGC-7901) were evaluated by CCK-8 method, and saponins 5 – 8 displayed certain cytotoxicities. The strong interactions between saponins 5 – 8 and SCUBE3, an oncogene for glioma cells, were displayed by molecular docking. [Display omitted] • Four cholestanol saponins were characterized from Paris fargesii var. petiolata , including two previously underscribed saponins (1–2). • Compound 1 was a rare 6/6/6/5/5 fused-rings cholestanol saponin with a rare disaccharide moiety linked at C-26 of aglycone. • The cytotoxicities of obtained compounds 1– 8 were evaluated. • The docking interactions between saponins 5 – 8 and SCUBE3 were described. [ABSTRACT FROM AUTHOR]

Five unusual seco-nortriterpenoids, 3 β -hydroxy-20,21-seco-30-nortaraxastan-20,21-dioic acid (1), 3 β -hydroxy-20,21-seco-30-nortaraxastan-20-oic-21-oate (2), 3 β -hydroxy-20-oxo-21,22-seco-30-nortaraxastan-22-oic acid (3), 3 β -hydroxy-19-oxo-20,21-seco-29,30-nortaraxastan-21-oic acid (4) and 3 β -hydroxy-19-oxo-20,21-seco-19-norlupan-21-oic acid (5) were isolated and elucidated from the anti-inflammatory activity fraction of the ethanol extract of Cirsium setosum. The structures of these compounds were established through spectroscopic methods. Preliminary biological assays showed that compounds 1 – 5 had significant inhibitory effect on NO production on lipopolysaccharide-stimulated RAW 264.7 cells, and compound 1 showed the strongest anti-inflammatory activity. This type of ring-opening compound is the first seco-triterpenoid structure discovered from the genus of Cirsium. [Display omitted] [ABSTRACT FROM AUTHOR]

Substituted hydrazides have significant potential as nonlinear optical materials. In this contribution, synthesis and structural (X-ray crystallography, UV, IR, and Raman spectroscopy) characterization of a novel NLO material, E- N '-(4-formylbenzylidene)furan-2-carbohydrazide (4FBC), is presented. The Hirshfeld surface analysis allowed for the investigation of the intermolecular interactions within the crystal structure and the most significant contacts with the neighboring units were examined. The structural characterization is amended by quantum-chemical optimization employing several common functionals, and a comparison between crystallographic and predicted parameters determined the appropriate level of theory. The CAM-B3LYP/6–311++G(d,p) level of theory was used for further calculations, as the lowest differences in bond lengths and angles were obtained for the structure optimized at this level of theory. The vibrational and UV-VIS spectra were assigned, and the effects of different groups were discussed. The experimental electronic transition energy was well reproduced upon optimizing the excited state. The Quantum Theory of Atoms in Molecules (QTAIM) and Natural Bond Orbital (NBO) theory were used to quantify intramolecular stabilization interactions. The NLO properties of 4FBC were proven through the Z-scan experimental determination of the absorption coefficient and nonlinear refractive index. [Display omitted] • E- N '-(4-formylbenzylidene)furan-2-carbohydrazide hydrate crystal has been prepared. • Structure and spectra analyses were done at CAM-B3LYP/6–311++G(d,p) level of theory. • Different intermolecular interactions within crystal structure were examined. • Intramolecular interactions were investigated using NBO and QTAIM analyses. • Z-scan analysis proved the possible use as a non-linear optical material. [ABSTRACT FROM AUTHOR]

The Divertor Tokamak Test (DTT) fusion machine is currently under construction at ENEA site in Frascati (Italy). The location has been identified as being at high seismic risk. Preliminary analyses, using both static equivalent and dynamic methods, of seismic effects from local response spectra have been carried out on the structure, namely the cryostat base, supporting the vacuum vessel, the magnets and the cryostat, and a reference design has been obtained. An update of the geological seismic surveys for the site showed a more severe local seismic response than previously considered. The analyses based on the updated seismic response revealed potential structural criticality for the base. Therefore, two possible seismic isolation solutions were considered to reduce the stress state. Finally, a comparison in terms of displacement and stress fields between the non isolated configuration and the two isolated ones is presented. [ABSTRACT FROM AUTHOR]

Sampling moiré is a spatial fringe pattern analysis method which can be used to retrieve displacement fields on the surface of deformed specimens marked by a periodic pattern. We prove that, under mild assumptions, Sampling Moiré (SM) is equivalent to another full-field method, namely the Localized Spectrum Analysis (LSA). The prospects opened up by this result concern two metrological indicators, namely the measurement bias (the retrieved displacement being affected by a systematic error) and the measurement resolution (limited by the propagation of sensor noise to displacement maps). Previous studies on LSA yield predictive formulas for measurement bias and displacement resolution. These formulas are adapted here to the case of SM. Relevant numerical studies enable us to assess to what extent those predictive formulas are satisfied, interpolation performed in SM and not in LSA affecting the quality of the final result. • A new theoretical proof that sampling moiré and localized spectrum analysis are equivalent. • This equivalence gives predictive formulas of measurement bias and measurement resolution for sampling moiré. • Numerical experiments assess the accuracy of these formulas. [ABSTRACT FROM AUTHOR]

[Display omitted] • The health-enhancing properties of Camellia japonica L. have been neglected. • Triterpenoid saponins (tea saponins) serve as an important class of active substances in C. japonica. • A strategy involved LC-Q-TOF untargeted analysis and spectrum similarity networking was applied. • The enrichment, structural prediction, isolation, and anticancer properties of tea saponins are carried. Camellia japonica L. is rich in bioactive compounds, but its health-enhancing potential is often overshadowed by its ornamental value. Notably, triterpenoid saponins are prominent due to their surfactant properties. MolNetEnhancer revealed 537 compounds in C. japonica leaves water extract, classified into 32 categories, including 38 triterpenoid saponins. To enrich triterpenoid saponins, the process of D101 resin chromatography was employed. Molecular networking analysis based on UPLC-Q-TOF and quantitative analysis based on HPLC revealed saponins concentrated in fractions 3 and 4 (68.3% transfer). MS2LDA and NAP predicted structures for 38 triterpenoid saponins, revealing nearly half of them are potential new compounds. Comprehensive chromatographic and spectroscopic methods were used for purification and structural illustration of triterpenoid saponins, yielding 13, including 7 new compounds. Statistical analysis and in vitro assays revealed the cytotoxic and anti-inflammatory activities of these triterpenoid saponins played a crucial role in the anticancer effects. [ABSTRACT FROM AUTHOR]