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The direct conversion of methane to methanol has attracted increasing interest due to abundant and low-cost natural gas resources. Herein, by anchoring Cr-oxo/-oxyhydroxides on UiO-66 metal–organic frameworks, we demonstrate that reactive anionic oxyl radicals can be formed by controlling the coordination environment based on the results of density functional theory calculations. The anionic oxyl radicals produced at the completely oxidized CrVI site acted as the active species for facile methane activation. The thermodynamically stable CrVI-oxo/-oxyhydroxides with the anionic oxyl radicals catalyze the activation of the methane C–H bond through a homolytic mechanism. An analysis of the results showed that the catalytic performance of the active oxyl species correlates with the reaction energy of methane activation and H adsorption energies. Following methanol formation, N2O can regenerate the active sites on the most stable CrVI oxyhydroxides, i.e., the Cr(O)4Hf species. The present study demonstrated that the anionic oxyl radicals formed on the anchored CrVI oxyhydroxides by tuning the coordination environment enabled facile methane activation and facilitated methanol production. [ABSTRACT FROM AUTHOR]

Heteroatom (such as Ti, Sn, Zr, and Hf) zeolites that contain Lewis acid site (LAS) centers with tetrahedral coordination confined in micropores with various topologies are able to catalyze reactions distinct from those catalyzed by Brønsted acid sites (BASs). In particular, these LAS centers are able to coordinate with two oxygen atoms of one or two oxygenated molecules on a single LAS simultaneously, which are suitable for the conversion of biomass-derived oxygenates via unique reaction pathways, and have been widely explored in the conversion of biomass-derived oxygenates to value-added products. In this review, methods of conventional hydrothermal synthesis, improved direct synthesis (such as interzeolite transformation and dry gel conversion) and post-synthesis (such as solid-state ion change, structural reconstruction and grafting) are compared. Next, approaches for the qualification and quantification of the location (framework or extra-framework), fine structure (closed or open), and acidity of heteroatom centers are summarized. Thereafter, we present the applications of Lewis acid zeolites in the conversion of platform oxygenates of hexoses, furan derivatives and acid derivatives via reactions of isomerization, Meerwein–Ponndorf–Verley reduction, oxidation, and ketonization. Notably, the integration of multiple steps into a one-pot cascade reaction for the conversion of oxygenates (for example, glucose to 5-hydroxymethylfurfural and furfural to γ-valerolactone) mediated by the synergy of LASs and BASs or metal sites is also discussed. Finally, the opportunities and challenges in the low-cost synthesis and large-scale application of Lewis acid zeolites for the green and sustainable synthesis of chemicals are proposed. [ABSTRACT FROM AUTHOR]

Understanding structural transformation and phase transition accompanying reactions in a solid as a catalyst or oxygen carrier is important to the design and optimization of many catalytic or chemical looping reaction processes. Herein, we combined density functional theory calculation with the stochastic surface walking global optimization approach to track the structural transformation accompanying the reduction of CuO upon releasing oxygen. We then used machine learning (ML) methods to correlate the structural properties of CuOx with varying x. By decomposing a reduction step into oxygen detachment and structural reconstruction, we identified two types of pathways: (1) uniform reduction with minimal structural changes; (2) segregated reduction with significant reconstruction. The results of ML analysis showed that the most important feature is the radial distribution functions of Cu–O at a percentage of oxygen vacancy [C(OV)] < 50% and Cu–Cu at C(OV) > 50% for CuOx formation. These features reflect the underlying physicochemical origin, i.e., Cu–O breaking and Cu–Cu formation in the respective stage of reduction. Phase diagram analysis indicates that CuO will be reduced to Cu2O under a typical oxygen uncoupling condition. This work demonstrates the complexity of solid structural transformation and the potential of ML methods in studying solid state materials involved in many chemical processes. [ABSTRACT FROM AUTHOR]

Catalytic direct deoxygenation (DDO) of phenolic compounds to aromatics is an appealing approach for utilization of biomass‐lignin with minimal amount of H2 consumption. Metal/reducible metal oxide catalysts provide two functionalities, i. e., C−H bond formation (hydrogenation) and C−O bond breakage (deoxygenation), required for this reaction that takes place at the interfacial perimeter sites. Strong metal‐support interactions (SMSI) can profoundly alter the density and property of such sites. This short review summarized recent advances in tuning SMSI for enhancing DDO of phenolics. The approaches of varying reduction temperature, modulation of crystal facets and crystal phases of metal oxide, and reduction of mixed metal oxide were discussed for the origin for formation of SMSI, the degree of SMSI, and its consequence on the DDO performance. The analysis revealed that intermediate degree of SMSI with maximal density of metal/oxide interfacial perimeter site enhances DDO while minimizing unfavorable side reactions. This short review highlights the concept of tuning the interfacial perimeter sites via SMSI for reactions which require multiple functionalities and take place at the metal/oxide interface. [ABSTRACT FROM AUTHOR]

Simple Summary: Cholangiocarcinoma (CCA) accounts for approximately 15% of primary liver cancers. CCA has a poor prognosis and, thus, more effective systemic treatments are needed. We tested opaganib and upamostat, drugs that target sphingosine kinase 2 and multiple serine proteases, primarily trypsins, which are highly expressed in CCA tumors. This study demonstrates the results of inhibiting these novel targets with these drugs individually and in combination in a patient-derived CCA xenograft mouse model. Upamostat is an orally available small-molecule serine protease inhibitor that is a highly potent inhibitor of trypsin 1, trypsin 2, trypsin 3 (PRSS1/2/3), and the urokinase-type plasminogen activator (uPA). These enzymes are expressed in many cancers, especially during tissue remodeling and subsequent tumor cell invasion. Opaganib (ABC294640), a novel, orally available small molecule is a selective inhibitor of the phosphorylation of sphingosine to sphingosine-1-phosphate (S-1-P) by sphingosine kinase 2 (SPHK2). Both sphingosine kinase 1 (SPHK1) and SPHK2 are known to regulate the proliferation-inducing compound S-1-P. However, SPHK2 is more critical in cancer pathogenesis. The goal of this project was to investigate the potential antitumor effects of upamostat and opaganib, individually and in combination, on cholangiocarcinoma (CCA) xenografts in nude mice. PAX165, a patient-derived xenograft (PDX) from a surgically resected CCA, expresses substantial levels of SPHK2, PRSS1, PRSS2, and PRSS3. Four groups of 18 mice each were treated with upamostat, opaganib, both, or vehicle. Mouse weights and PAX165 tumor volumes were measured. Tumor volumes in the upamostat, opaganib, and upamostat plus opaganib groups were significantly decreased compared to the control group. [ABSTRACT FROM AUTHOR]

The selective photocatalytic reduction of CO2 to CH4 remains a challenge because there is a need for not only strong adsorption sites for the intermediates, but also optimal proton-feeding sites on the photocatalyst surface. Herein, a synergistic dual-site function between in situ-generated Ni0 and Ni2P on carbon nitride nanosheets (CN) for photocatalytic reduction of CO2 to CH4 is presented. The highest CH4 production rate of 69.03 μmol g−1 h−1 is achieved on Ni2P/CN-0.5 in an aqueous suspension. Detailed analyses show that the promotion of CH4 is closely correlated with the formation of Ni0 sites due to light irradiation, which is confirmed by tracking the compositions of Ni2P/CN-0.5 through XPS and HRTEM characterization. Density functional theory calculations have been combined with CO-TPD and in situ FTIR spectra to reveal the synergy between in situ-generated Ni0 sites and Ni2P. It shows that the Ni0 sites can stabilize the key intermediate *CO, while the Ni0–Ni2P interface can promote *H transfer from Ni2P to Ni0. Therefore, the CO intermediates are rapidly protonated to form CHO* instead of being desorbed from the surface to produce CO, and subsequently CHO* will be converted into CH4. This work demonstrates a new strategy of designing highly efficient photocatalysts with synergistic catalytic sites for CO2 conversion to hydrocarbons. [ABSTRACT FROM AUTHOR]

Aim: Postpartum depression is prevalent worldwide and seriously endangers maternal and child health. Previous studies have demonstrated the effectiveness of psychological and psychosocial intervention programmes in preventing postpartum depression. However, the literature offers limited practice guidance. Therefore, this study aimed to deeply analyse prior findings to gather rich evidence‐based information on this topic. Methods: Using the distillation and matching model, we conducted a systematic review of psychological and psychosocial interventions used to effectively prevent postpartum depression. Four researchers trained in coding system independently read eligible studies and identified reliable (Cohen's kappa >0.40) and frequently occurring (frequency ≥3 winning study groups) practice elements. Results: Our review included 36 studies containing 37 winning study groups. Fourteen practice elements were identified and subsequently divided into six categories: postpartum practical problems‐related, social support‐related, interpersonal psychotherapy‐related, cognitive behavioural therapy‐related, labour trauma‐related and non‐specific techniques. The most common practice elements were baby care skills and mother–infant bonding/interaction enhancement. Inter‐rater reliability averaged 0.86, ranging from 0.48 to 1. Conclusion: The practice elements identified in this study provide rich evidence‐based information that can guide clinical practitioners in selecting or developing effective, realistically available intervention programmes. [ABSTRACT FROM AUTHOR]

The inverse synthetic aperture radar (ISAR) image is a kind of target feature data acquired by radar for moving targets, which can reflect the shape, structure, and motion information of the target, and has attracted a great deal of attention from the radar automatic target recognition (RATR) community. The identification of ISAR image components in radar satellite identification missions has not been carried out in related research, and the relevant segmentation methods of optical images applied to the research of semantic segmentation of ISAR images do not achieve ideal segmentation results. To address this problem, this paper proposes an ISAR image part recognition method based on semantic segmentation and mask matching. Furthermore, a reliable automatic ISAR image component labeling method is designed, and the satellite target component labeling ISAR image samples are obtained accurately and efficiently, and the satellite target component labeling ISAR image data set is obtained. On this basis, an ISAR image component recognition method based on semantic segmentation and mask matching is proposed in this paper. U-Net and Siamese Network are designed to complete the ISAR image binary semantic segmentation and binary mask matching, respectively. The component label of the ISAR image is predicted by the mask matching results. Experiments based on satellite component labeling ISAR image datasets confirm that the proposed method is feasible and effective, and it has greater comparative advantages compared to other classical semantic segmentation networks. [ABSTRACT FROM AUTHOR]

Water is typically treated as an implicit solvent in modeling electrochemical reactions in an aqueous environment. Such treatment may not be adequate, as a series of concerted or sequential proton-electron transfer steps that explicitly involve water molecules are likely to play important roles in a reaction, such as the electrochemical hydrogenation of CO2. Herein, we use the electrochemical hydrogenation of CO2 on the Sn(112) surface as a model, and employ the density functional theory (DFT) method to examine the effect of up to 12 explicit water molecules on the stability of the hydrogenation intermediates. Our results show that six water molecules are needed to account for the local interaction between an intermediate and the water solvent. Furthermore, the hydrogen bonding interaction between the explicit water molecules and intermediates causes a significant stabilization to the O-containing intermediates, such as the HCOO* and CHO* + OH* species. The inclusion of explicit water molecules also altered the prediction of the potential-limiting step from the formation of H* atoms without the explicit water molecules to the formation of H2COO* in the presence of water molecules and increased selectivity towards methane. This work provides useful insights into the electrocatalytic hydrogenation of CO2, emphasizing the importance of including explicit water molecules to account for the hydrogen bonding interaction between solvent water molecules and the reaction intermediates. [ABSTRACT FROM AUTHOR]