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• Investigated the evolution process of microwave-induced cracks based on the experimental tests and numerical tests. • Studied the effect of the specimen size on microwave-induced fracturing behaviours. • Elucidated the mechanisms responsible for size-dependent microwave-induced fracturing behaviours. The effect of specimen size on microwave-induced fracturing of rocks has not been well understood. In this study, the experimental tests using open-ended microwave and numerical simulations coupling COMSOL Multiphysics and four-dimensional lattice spring model (4D-LSM) were carried out to investigate the evolution process of microwave-induced cracks, and to elucidate the mechanisms responsible for size-dependent microwave-induced fracturing. The experiments show that with the increase of the specimen dimension, the number of microwave-induced cracks is almost constant, and the total crack length first increases and then decreases, while the maximum crack width and maximum crack depth decrease gradually. A comparison of the experimental and numerical temperature characteristics as well as cracking characteristics indicates that the models established in this study are reasonable in the simulation of the rock fracturing behaviours. The numerical results show that the crack initiation time increases logarithmically with the increase of the specimen dimension. For the small-sized specimens, the microwave-induced cracks started from the outer boundary of the specimen and propagated toward to specimen center and into the depth. For the medium-sized and large-sized specimens, the microwave-induced cracks initiated near the outer boundary of the antenna aperture, and then propagated toward to the center of the specimen and the outer boundary of the specimen. The main reason for the size-dependent of fracturing behavior is that the local fracture energy will dramatically decrease when the crack is approaching the specimen boundary. [ABSTRACT FROM AUTHOR]

Microwave fracturing of rocks prior to mechanical breakage has the potential to significantly enhance rock breakage efficiency while reducing the wear of cutters/bits of mechanical excavators. However, rocks in nature require a vastly different microwave power intensity to be fractured, and they tend to fail in varying patterns under different power intensities. At present, there is no established suggest method for selecting the most suitable microwave antenna to fracture a specific rock in the field. In this study, we compared the technical characteristics of the four open-ended waveguide-based antennas: namely, the horn antenna, the standard waveguide antenna, the converging waveguide antenna, and the dielectric-loaded converging waveguide antenna. Using a 6 kW microwave source and these antennas, we treated four types of hard rocks. We investigated the impact of antenna type on rock fracturing and found that depending on the rock type and antenna used, rocks were typically fractured or weakened in the pattern of cracking, spalling, melting, or a combination thereof. Based on our observations, we have, for the first time, proposed a method for selecting the optimal antenna to fracture rocks with varying microwave fracturability indexes. This paves the way for the commercialization of microwave-assisted mechanical rock breakage. • Compared the technical merits of four types of open-ended waveguide-based microwave antennas. • Evaluated the antenna performance by treating four types of rocks with different microwave fracturability indexes (MFIs). • Proposed a method for selecting the optimal antenna for different types of rocks based on their MFIs. [ABSTRACT FROM AUTHOR]

• A Ni and N-doped porous interconnected carbon (NiNPIC) was prepared by a rapid and facile ultrasonic assisted method. • A high current density of 10.2 mA cm−2, an FE of 95.1%, a TOF of 1886 h-1 for CO 2 -to-CO at a low over-potential of -0.54 V. • The interconnected structure, high surface area and rich Ni-N-C moisture leads to better electron transfer and lower interface resistance. • The hierarchical porous structure greatly enhanced the mass transport in the electrode. Zn-Ni bi-metal MOFs were employed as precursors to prepare Ni-N-doped porous interconnected carbon (NiNPIC) catalysts for enhanced electrocatalytic activity and selectivity of the CO 2 RR. It was found that the Ni load amounts could be precisely controlled by altering the Ni dosage in the bi-metal MOF precursors, and the gradually increased Ni-N species leads to the enhanced CO 2 RR performances. The high surface area as well as interconnected porous structures of the catalysts provide highly accessible Ni-N sites and convenient channel for mass diffusion, which gives rise to better electron transfer, lower interface resistance and high electrolyte/gases transport in the CO 2 RR. Thanks to these structural advantages, the optimized catalyst demonstrated efficient convert CO 2 into CO with a current density of 10.2 mA cm−2 (113 mA mg−1), a FE CO of 95.1%, a production rate of 542 μmol m−2 s−1 (36.1 μmol mg−1 min−1), and outstanding electrochemical stability at a moderate over-potential of 0.54 V (vs. the RHE). [ABSTRACT FROM AUTHOR]

Abstract The Dadushan Tunnel, which is located in the southwestern karst region of China in Guizhou Province, is one of the key elements of the Hukun High-Speed Railway. Cavities occur unpredictably in the tunnel, and well-developed karst conduits are frequently encountered. These features result in safety problems, such as water gushing and rapid flooding. In this paper, on the theoretical basis of the surface Magnetic Resonance Sounding (MRS) method, we propose Tunnel Magnetic Resonance Sounding (TMRS) in the tunnel space model and derive the expression of the MRS response signal with a vertical antenna. A direction angle formula is then created to calculate the perpendicular component of the transmitting field at arbitrary geomagnetic field and antenna directions. In addition, we present a comprehensive study on the TMRS based on forward modeling and numerical experiments. The relationship between the magnetic resonance signal response and the position and water content of water-bearing structures is obtained by forward modeling. In the numerical examples, the inversion results agree with the numerical model. The application of the method to a case study involving the Dadushan Tunnel indicates that the prediction results agree well with the excavation results. This paper establishes a theoretical basis for the development of a magnetic resonance sounding instrument for use in tunnels for the advanced detection of water-rich geological structures that can produce tunnel disasters. [ABSTRACT FROM AUTHOR]

Three new indolocabazole analogues ( 1-3 ), one eudesmane-type derivative ( 4 ), one bisphenol A propyl ether analogue ( 5 ), were purified from the fermentation of the marine- derived Streptomyces sp. A68 and its Rifampicin-resistant mutant strain R-M1. The structures were established through the interpretation of spectroscopic data combined with literature data review. The absolute stereochemistry of 1 was further confirmed by X-ray crystallography analysis. Bioactivity test showed that compounds 1-3 had evident cytotoxic activity towards PC-3 cell lines. Furthermore, 1-3 and 5 also exhibited potent kinase inhibitory activity against PKCα, ROCK II and BTK with IC 50 of values ranging from 0.17 to 3.24 μM. [ABSTRACT FROM AUTHOR]

• A resilience assessment framework for the GLSN across two dimensions, including static resilience and dynamic resilience. • Identification of overlapping community structure and key nodes with the clique percolation method. • A network disintegration method to consider the impact of traffic flow on system resilience assessment. • An innovative, knock-on effect simulation model with tailored, local weighted flow redistribution rules for dynamic resilience assessment. As a critical infrastructure system of modern society, the global liner shipping network (GLSN) has become increasingly complex and thus vulnerable to disruptions. This study proposes a resilience assessment framework for the GLSN across two dimensions, including static resilience and dynamic resilience. First, by leveraging high-frequency vessel movement data, the GLSN is constructed. Then, with the clique percolation method (CPM), overlapping community structures and key nodes can be identified. The static resilience assessment is initially conducted using simulation techniques, with nodes attacked through pre-designed scenarios. Then, a network disintegration method is employed to consider the impact of traffic flow on system resilience assessment, which separates the weighted GLSN into different layers for evaluation. The results show that both overlapping community structure and traffic flow significantly impact the resilience evaluation of the GLSN. Finally, to assess the dynamic resilience of the GLSN, we propose an innovative, knock-on effect simulation model with tailored, locally weighted flow redistribution rules. It provides a method for predicting the impacts of potential global disruptions (e.g., the COVID-19 pandemic) and critical maritime infrastructure failures (e.g., the Suez Canal obstruction) on the shipping network, which are of great concern not only to academia but also to industry. [ABSTRACT FROM AUTHOR]

Lag consensus is a phenomenon where followers track the trajectory of the leader with a time delay. By using lag consensus, a protocol is designed for agents to behind the leader at different times, so as to avoid congestion. In this paper, aiming to the lag consensus of second-order nonlinear multi-agent systems, a control protocol for each follower based on local information of neighboring agents is proposed, and an adaptive feedback control protocol is also given. Moreover, the multi-agent systems with noisy environment are considered. The results suggest that our protocol is robust to the noise. Finally, simulation examples are given to illustrate our theoretical analysis. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Dragon?s blood has been used as a famous traditional medicine since ancient times by many cultures. It is a deep red resin, obtained from more than 20 different species of four distinct genera. Red resin of Dracaena cochinchinensis S.C. Chen, known as Chinese Dragon?s Blood or Yunnan Dragon?s Blood, has been shown to promote blood circulation, alleviate inflammation, and to treat stomach ulcers, diarrhea, diabetes, and bleeding. This study investigated an effective approach to identify natural therapeutic agents for neurodegeneration from herbal medicine. The dichloride extract and isolated effective constituents of Chinese Dragon?s Blood showed quinone oxidoreductase 1 (NQO1) inducing activity and anti-inflammatory effect significantly, which are therapy targets of various neurodegenerative diseases. Materials and methods: Multiple chromatography and spectra analysis were utilized to afford effective constituents. Then Hepa 1c1c7 and BV-2 cells were employed to assay their NQO1 inducing and anti-inflammatory activities, respectively. Results: Bioactivities guided isolation afforded 21 effective constituents, including two new polymers cochinchinenene E (1), cochinchinenene F (2) and a new steroid dracaenol C (16). The main constituent 3 (weight percent 0.2%), 5 (weight percent 0.017%), 4 (weight percent 0.009%), 9 (weight percent 0.094%), 10 (weight percent 0.017%) and 8 (weight percent 0.006%) are responsible for the anti-inflammatory activities of Chinese Dragon?s Blood. While, new compounds 1, 2 and known compounds 5, 11 showed good NQO1 inducing activities. The brief feature of the activities and structures was discussed accordingly. Conclusion: Overviewing the bioactivities and phytochemical study result, 4'-hydroxy-2,4-dimethoxydihydrochalcone (3) and pterostilbene (5) as effective constituents of Chinese Dragon?s Blood, were found to be potential candidate therapeutic agents for neurodegenerative diseases. [Copyright &y& Elsevier]

The thermal damage induced by microwave treatment in rocks has not been well explored, especially when using the dielectric-loaded converging waveguide antennas (DLCWAs). In this paper, the effects of microwave power level, heating time and working distance on the temperature increase, ultrasonic wave velocity reduction, and more importantly, the fracturing characteristics and the damage zone, are comprehensively investigated using a 6 kW microwave source and a customized DLCWA. A novel method is also proposed to adjust the P-wave velocity (V p) reduction across the thickness of the specimens and to determine the equivalent damage zone. The results show that the temperature and high temperature area, crack number, length and density, and the V p reduction rate as well as the damage zone all increase as either the power level or the heating time increases and decrease as the working distance increases. The damage zone can be divided into the crushed zone, fracture zone and discrete fragment zone based on the crack characteristics and the crack generation mechanisms. The method proposed is demonstrated to be reliable in predicting the damage zone induced by microwave heating. • Used a dielectric loaded converging waveguide antenna to fracture a biotite diorite. • Investigated the effects of microwave power level, heating time and working distance on thermal fracturing. • Proposed a novel method to estimate the P-wave velocity distribution across the total thickness. • Determined the equivalent thermal damage zone based on the spatial P-wave velocity reduction. [ABSTRACT FROM AUTHOR]

Abstract: The dynamical behavior of a stage structure population model with birth pulses and impulsive pest management strategy is discussed analytically and numerically. It is assumed that birth pulse and impulsive pest management strategy act with the same period, but not simultaneously. The existence and stability of the positive 2T-period solution are investigated. By using center manifold theorem and bifurcation theorem, the conditions of existence for flip bifurcation are derived. Moreover, some detailed numerical results for phase portraits, periodic solutions, bifurcation diagram, and chaotic attractors, which are illustrated with two examples, are in good agreement with the theoretical analysis. [Copyright &y& Elsevier]

Abstract: From the twigs of Eurycorymbus cavaleriei, seven new benzeneacetic acid derivatives cavaol A–G (1–7) were isolated. The structures were elucidated on the basis of the results of spectroscopic (NMR, IR, UV and MS) analysis. In the present study, the quinone reductase (QR) induction activities of compounds 1–7 were assayed. Compounds 3 and 4 showed moderate QR induction with concentrations to double the enzyme activity (CD) of 9.9±0.3 and 7.9±0.5μg/mL, respectively. LC-MS-MS analysis revealed that the quinone reductase induction activity of compounds 3 and 4 was not due to alkylating the sulfhydryl groups of Keap1. There must be some other pathways for compounds 3 and 4 to induce quinone reductase. [Copyright &y& Elsevier]

Abstract: Four compounds, including one new lignan cavaol H (1), one new coumarinolignoid 5′-hydroxycleomiscosin B (4) and two known lignans (2–3) were isolated from the 95% ethanol extract of the twigs of Eurycorymbus cavaleriei. Their structures were established on the basis of various spectroscopic analyses including 1D-(1H, 13C, and DEPT) and 2D-NMR (COSY, HMQC, and HMBC). The absolute stereochemistry of the two known lignans was firstly reported in this article by 1H NMR studies on Mosher''s ester derivatives. In the present study, quinone reductase induction activities of compounds 1–4 were assayed, compound 4 showed moderate quinone reductase induction with concentration to double the enzyme activity (CD) of 10.5±0.8 μg/mL. Then we established LC-MS-MS analysis of glutathione (GSH) incubation with compound 4 to explain whether compound 4 induced quinone reductase through alkylating of the sulfhydryl groups of Keap1. Reconstructed selected ion chromatogram (SIC) of m/z 706 after compound 4 incubation with GSH was different from that with Tris–HCl buffer solution, which meant the quinone reductase induction activity of compound 4 attributed to alkylating the sulfhydryl groups of Keap1. [Copyright &y& Elsevier]

Abstract: The dichloromethane fraction of the crude ethanol extract of Echinops grijissi Hance roots exhibited different cytotoxicity against a panel of four human tumor cell lines, HepG2, K562, HL60 and MCF-7. By a bioassay-guided fractionation, eight thiophenes were isolated from the dichloromethane fraction, one of them was isolated from the plant for the first time. And they were assayed for their toxicity against the cell lines in order to compare their relative anti-tumor activity and find candidates of potential anti-tumor drugs. The dichloromethane fraction and isolated thiophenes showed different activity against the cell lines, and the anti-tumor activity of the dichloromethane fraction was also studied in vivo in S180 implanted ICR mice, however, it exhibited no anti-tumor activity at dosage of 20 or 40mg/kg/d. There were also deaths recorded and the animals showed signs of toxicity when the dosage is 200mg/kg/d. [Copyright &y& Elsevier]

Abstract: Two new diterpenes, including one with an unprecedented 6/6/8 carbon ring skeleton (curcuminol D, 1) and another with 19 carbons (curcuminol E, 2), were isolated from the radix of Curcuma wenyujin. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis, mainly NMR and MS. Compounds 1 and 2 were tested in vitro for their cytotoxic activity against the human cancer cell lines HL-60 and K562. Compound 1 exhibited medium cytotoxicity with IC50 values of 11.2 and 3.2μg/mL, respectively, and compound 2 showed better activity against the above cancer cell lines with IC50 values of 4.2 and 2.7μg/mL, respectively. [Copyright &y& Elsevier]

The improved electron acceptability of phthalocyanine/ketjenblack compounds can enhance the adsorption strength of the *COOH and inhibit the rival HER in ECR, thus showing extremely high synergistic catalytic activity for converting CO 2 to CO. • NiPc/KB was synthesized by a rapid and facile one-step in-situ π-π stacking method. • TOF for converting CO 2 to CO is enhanced by greater than 251 times. • Faradaic efficiency for CO reaches to 98.2%. • DFT calculations reveal the synergistic catalytic processes of NiPc/KB in ECR. Designing a facile and high-yield strategy to prepare highly active and selective electrocatalysts for CO 2 reduction is beneficial to the industrial application. However, there are still many challenges in catalyst preparation. Besides, further mechanism studies on catalytic process for enhancing CO 2 reduction are not clear. Herein, We have found that nickel phthalocyanine facilely incorporated into defect-rich ketjenblack by π-π stacking method can greatly improve its ECR performance. Nickel phthalocyanine/ketjenblack compounds show high selectivity and activity, 251 times turnover frequency for converting CO 2 to CO compared to pristine nickel phthalocyanine, and keep above FE CO of 90% under large potentials regions from −0.65 to −1.05 V vs RHE. Fundamentally density functional theory (DFT) calculations reveal that nickel phthalocyanine molecules anchored onto ketjenblack enhance the electron acceptability, decrease the formation energy of the *COOH and inhibit the rival hydrogen evolution reaction (HER), thus showing extremely high synergistic catalytic properties in ECR. [ABSTRACT FROM AUTHOR]

Abstract: Two new carabrane sesquiterpenes, 4,8-dioxo-6β-methoxy-7β,11-epoxy carabrane (1), and its isomer, 4,8-dioxo-6β-methoxy-7α,11-epoxy carabrane (2) were isolated from the roots of Vladimiria souliei. Their structures were elucidated by spectroscopic methods (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR). [Copyright &y& Elsevier]

This article reports a clinical case of an 8-year-old boy who sustained avulsion of the maxillary right central incisor and the maxillary left lateral incisor. The avulsed teeth were kept in adverse extraoral dry conditions for 1 h from the moment of trauma until their replantation. The prognosis of tooth replantation is dependent on multiple factors such as methods of teeth storage in vitro, endodontic intervention, extra-oral time, and type of retention employed. The main reasons for root resorption in this case may be the extra-oral time, the initial replantation, or the delayed endodontic treatment. [ABSTRACT FROM AUTHOR]

Water and KCl solutions were exposed to four different magnetic fields for 20 min respectively. Influences of magnetic field on microscopic structures and macroscopic properties of water and KCl solutions were studied by FTIR and the continuous spectrum techniques of linearly polarized light in ultraviolet, visible and near-infrared areas. Simultaneously, these quantities were determined for unmagnetized samples, as references. It was found that in the UV–vis area, the transmittance of all samples presented different phenomena when the incident light with different polarized, it resulted from the orientation of water molecules affected by the static magnetic field and the spiral motion of ions in the magnetic field. The IR spectrum showed that KCl had a significant structure-breaking effect when the intensity of the magnetic field increased and the absorption in the spectrum of KCl was a reflection of the perturbations that water bore in the presence of K + and Cl − ions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two compounds conjugating with GSH well were identified from the DEPP by UPLC–ESI-MS. [•] Three new withanolides were isolated and their structures were characterized. [•] Compounds 1 and 2 had potent QR-induce activity. [Copyright &y& Elsevier]

Abstract: Aromatase, a cytochrome P450 (CYP19) enzyme that catalyses the conversion of androgens to oestrogens, is an important target for breast cancer therapy. Flavonoid has been proved to be potential therapeutic agent for breast cancer by inhibiting the activity of aromatase and is one of the main active constituents of mulberry leaves. In this study, twelve flavonoids, 3,5,7,3′,4′-pentahydroxyflavone-3-glucosyl-glucoside/3,5,7,3′,4′-pentahydroxyflavone-3,7-diglucoside, mulberroside F, 3,5,7,3′,4′-pentahydroxyflavone-3-(6″-malonyl)-glucoside, 3,5,7,4′-tetrahydroxyflavone-3-(6″-malonyl)-glucoside, 3,5,7,4′-tetrahydroxyflavone-3-O-(6″-acetyl)-glucoside, 3,5,7,3′,4′-pentahydroxyflavone-3-rutinoside, 3,5,7,3′,4′-pentahydroxyflavone-3-glucoside/3,5,7,2′,4′-pentahydroxyflavone-3-glucoside, kuwanon G, 5,7,3′,4′-tetrahydroxyflavone-7-rutinoside/3,5,7,4′-tetrahydroxyflavone-3-rutinoside, 3,5,7,4′-tetrahydroxyflavone-3-glucoside, 3,5,7,3′,4′-pentahydroxyflavone-3-O-(6″-acetyl)-glucoside and chalcomoracin/mongolicin F, and three fatty acids, 9,12,15-octadecatrienoic acid, compounds 12 and 13, were tentatively identified by HPLC-DAD-ESI-MS/MS method. Seven of the compounds, 3,5,7,3′,4′-pentahydroxyflavone-3-rutinoside, 3,5,7,3′,4′-pentahydroxyflavone-3-glucoside/3,5,7,2′,4′-pentahydroxyflavone-3-glucoside, 3,5,7,4′-tetrahydroxyflavone-3-glucoside, chalcomoracin/mongolicin F and 9,12,15-octadecatrienoic acid, were revealed unequal binding capability for aromatase by HPLC-DAD-ESI-MS/MS. [ABSTRACT FROM AUTHOR]

Abstract: Litchi (Litchi chinensis Sonn.) is widely accepted as a delicious fruit in China and its seeds have been commonly used in traditional Chinese medicine to relieve neuralgic pain. In the present study, chemical investigation of the 95% ethanol extract of Litchi chinensis seeds led to the isolation of four new compounds, 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β-8-catechin) (5), 2β,3β-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4α-8-epicatechin) (7), litchiol A (9) and litchiol B (12), together with 11 known ones, 2,5-dihydroxy-hexanoic acid (1), soscopoletin (2), coumaric acid (3), protocatechuic acid (4), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β−8)-epicatechin (6), pterodontriol d-6-O-β-d-glucopyranoside (8), Narirutin (10), naringin (11), dihydrocharcone-4′-O-β-d-glucopyranoside (13), pinocembrin-7-rutinoside (14), pinocembrin-7-neohesperidoside (15). Their structures were mainly elucidated on the basis of NMR, MS, IR, CD and UV spectral evidences. Antioxidant activities of 14 compounds were determined by DPPH radical-scavenging assay and Trolox equivalent antioxidant capacity assay, and the results showed that four compounds, protocatechuic acid (4), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β-8-catechin (5), 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β−8)-epicatechin (6), 2β,3β-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4α-8)-epicatechin (7), exhibited moderate antioxidant activities. [ABSTRACT FROM AUTHOR]

Abstract: Keap1–Nrf2 pathway has emerged as a regulator for the endogenous antioxidant response, which is critical in defending cells against carcinogenesis. Herein, we demonstrated that depleting the cellular level of glutathione (GSH) by a novel electrophilic agent 2-(pro-1-ynyl)-5-(5,6-dihydroxypenta-1,3-diynyl) thiophene (PYDDT) could activate Keap1–Nrf2 pathway. In above process, it was found that Keap1 was modified by S-glutathionylation, an important post-translational modification of protein cysteines with critical roles in oxidative stress and signal transduction. We concluded from our findings that conjugation with intracellular GSH by PYDDT might lead to Keap1 S-glutathionylation and was a key event involved in its Nrf2 inducing activity. [ABSTRACT FROM AUTHOR]

Abstract Alokicenones A-H (1–8), eight new tetrahydroanthracenes and one known okicenone (9) were identified from the secondary metabolites of mangrove-derived Streptomyces sp. HN-A101. Their structures were elucidated by HRESIMS and NMR spectroscopic data. The absolute configurations of them were determined by the calculated and experimental ECD curves. Compounds 1–2 and 9 showed moderate cytotoxicity against HCT116 and SW620 cancer cell lines with IC 50 values from 0.63 to 7.73 μ M. In addition, compounds 1 – 3 and 7 – 9 also exhibited inhibitory activities against ROCK2 or BRD4. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Thioquinomycins A-D (1–4), four novel naphthothiophenediones were isolated from the rice-based medium of the marine-derived Streptomyces sp. SS17F. Their structures were elucidated by spectroscopic methods and HRESIMS data. The absolute configurations of all the compounds were elucidated by X-ray diffraction analysis, ECD and Mosher's method combined with 19F-NMR. Compounds 1–4 showed moderate cytotoxicity against NCI-H1975 with IC 50 values from 17.5 to 50 μ M. In addition, compounds 1–4 also exhibited inhibitory activities against PKCα and ROCK2 protein kinase. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Ten new and 13 known prenylated 2,5-diketopiperazines (2,5-DKPs) were identified from co-culture of Penicillium sp. DT-F29 with Bacillus sp. B31. The constitutions and relative configurations of new compounds were established by 1D and 2D NMR spectroscopic data analysis. The isolated 2,5-DKPs in bioactivity test showed bromodomain-containing protein 4 (BRD4) inhibitory activities, and compound 14 , with IC 50 values of 6.54 μ M, was potential for BRD4 inhibitor discovery. [ABSTRACT FROM AUTHOR]

Breast cancer metastasis is a major challenge in clinical therapy because of the absence of effective treatments. Rho-associated coiled-coil kinase (ROCK), which is essential for cell invasion and migration, has recently been suggested as a potential target for the treatment of cancer metastasis. Herein, we report the structure−activity relationships (SAR) of indolocarbazoles against ROCK2 and reveal the crucial role of the C-3 hydroxyl for ROCK2 inhibition. The most potent unglycosylated aglycone THK01 was demonstrated to bind to and stabilize ROCK2 with potent anti-metastatic effects in breast cancer in vitro and in vivo with no obvious toxicities. Further mechanistic studies revealed that the anti-metastatic effect of THK01 was closely related to the suppression of STAT3Y705 activation. Moreover, THK01 exhibited excellent selectivity over the isoform protein ROCK1 (>100-fold). Taken together, with low toxicity, the ROCK2 inhibitor THK01 potently inhibited breast cancer metastasis through the ROCK2-STAT3 signaling pathway, which offers a new opportunity for the treatment of metastatic breast cancer. [Display omitted] • An extensive SAR study of indolocarbazoles against ROCK2 was established. • The binding modes were verified by molecular docking and the single-point mutated ROCK2. • THK01 significantly suppresses breast cancer metastasis in vitro and in vivo. • THK01 inhibits the activation and nuclear translocation of STAT3. • THK01 is a highly isoform-selective ROCK2 inhibitor. [ABSTRACT FROM AUTHOR]

• The multiple functions of axial oxygen ligand in improving ORR activity were exploited. • The axial oxygen ligand may participate in the catalysis. • The homolateral adsorbate evolution mechanism is preferential for oxygen reduction. • The dynamically wobbly oxygen will modulate the orbital orientation of metal atom. The catalytic activity of single metal atom were effectively enhanced by different coordination environments, and the underlying improvement mechanisms are generally ascribed to the electronic structure modification by in-plane ligands. Herein, taking the recently synthesized MoNO composites modified carbon as representative, we clarified the multiple functions of axial oxygen ligand in improving the oxygen reduction activity. The active Mo atom is protruded from graphene plane due to the interaction with axial oxygen ligand, and during adsorption of oxygenates, the hanging oxygen ligand would wag to leave space and meanwhile tune the orbital orientation of Mo atom, giving rise to an optimal adsorption strength on the side in presence of oxygen ligand. The dynamic oxygen ligand may participate in the catalysis through hydrogenation reaction at the coadsorption stage with oxygen intermediate. The obtained overpotential of 0.35 V on MoN 2 O 1 -pen-gra along homolateral adsorbate evolution mechanism is comparable to recent experiments, approving the reliability of models and mechanism proposed in current study. The present results could provide some new insights into the functions of axial ligands and further guide the rational design of axial coordination to improve the catalytic performance. Graphical Abstract: [Display omitted] [ABSTRACT FROM AUTHOR]

To estimate global crude oil trade flows, current research either considers only crude oil tankers, or simply applies external information to distinguish between crude and refined product oil cargoes transported by coated product tankers; these limitations often reduce an estimation's accuracy or compromise replicability. Our methodology directly addresses these issues by applying the random forest (RF) ensemble learning technique to Automatic Identification System (AIS) data in order to predict the cargo types of coated product tankers. By leveraging domain knowledge, we construct a set of unique input variables for the RF model, and use its predictions to quantify the global crude oil trade in a more accurate manner. Our estimation shows that coated product tankers were responsible for approximately 8% of global seaborne crude oil trade from 2017–2020. Further, unanticipated variations in the crude oil volume carried by these tankers are consistent with several major historical oil trade disruptions. Our study further extends current applications of AIS data in the domains of operations management and maritime transportation, and facilitates the exploration of the more minute characteristics of oil transportation. The resulting shipping dataset and associated decomposition strategy also enable relevant stakeholders to quickly identify emerging trade flow risks and adapt more effectively. • Predict the cargo types of coated product tankers by random forest method. • Construct a set of unique input variables leveraging domain knowledge. • Use predictions to quantify the global crude oil trade in a more accurate manner. • Estimation shows that coated product tankers responsible for approximately 8% of global seaborne crude oil trade from 2017–2020. [ABSTRACT FROM AUTHOR]

Highlights: [•] Eleven compounds from PA conjugated well with GSH. [•] Three new withanolides along with four known ones were isolated. [•] QR induction activity was measured for these compounds. [•] Two compounds showed potent QR induction activities. [•] Three compounds showed moderate QR induction activities. [Copyright &y& Elsevier]