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To explore the clinical effect of allogeneic sclera transplantation combined with tarso-conjunctival flap in total excision of divided eyelid nevus. Eleven patients (three male and eight female patients) who experienced divided nevus of the eyelids between January 2014 and April 2020 were recruited to this retrospective study. All lesions were thick, darkly pigmented, presented with a wart-like appearance, and invaded the eyelid margin and tarsal conjunctiva. The surgical method involved a full-thickness lesion excision; then, the posterior defect was reconstructed by sliding the residual tarso-conjunctival flap forward and allogeneic sclera transplantation, and the anterior defect was reconstructed with sliding flaps, rotating flaps, and free skin grafts. Neither malignant transformations nor recurrences were observed after a follow-up of more than one year. The eyelid shape was normal, the rim of the eyelid was smooth, there was no dissolution or rejection of the allogeneic sclera, and the eyelid had good mobility. All the flaps used were viable, soft, and thin. The most frequent complication was the loss of eyelashes in the reconstructed area. For divided nevus of the eyelids invaded the eyelid margin and tarsal conjunctiva, total excision is a better decision, regardless of tumor recurrence or aesthetic considerations. The posterior defect reconstruction through sliding residual tarso-conjunctival flaps combined with allogeneic sclera transplantation is simple and effective. [ABSTRACT FROM AUTHOR]

• The first report about furanocoumarin rhamnosides from Angelica dahurica roots. • Four new furanocoumarin glycosides and eight known compounds from this plant. • Acid hydrolysis and enzymatic hydrolysis were used to elucidate the absolute configurations of new compounds. • The mushroom tyrosinase inhibitory activities of isolated compounds were tested. Angelica dahurica is an important medicinal plant, which has been widely used in medicines and skin-whitening products. In the investigation of phytochemicals present in A. dahurica roots, three unusual furanocoumarin rhamnosides, angelicosides I–III (1 – 3), one undescribed furanocoumarin glucoside, angelicoside IV (4), together with eight known compounds (5 – 12) were isolated. Their structures were characterized by a combination of UV, IR, NMR, HRESIMS, along with acid hydrolysis and enzymatic hydrolysis. All the isolated compounds were tested for their mushroom tyrosinase inhibitory activities, and compounds 1 , 2 , and 11 showed moderate activities. [ABSTRACT FROM AUTHOR]

In this paper, the trans-media hydrodynamics of a multi-rotor hybrid aerial underwater vehicle (HAUV) is studied base on experiments and machine learning. First, experiments are conducted to obtain the hydrodynamic forces during water exit/entry. Then, based on the experimental data and phenomena, it is evident that the multi-rotor HAUV's total resistance, particularly the impact of the arms, should not be ignored. The overall resistance is primarily affected by the depth and velocity at constant velocity. The total resistance increases as the velocity increases. The maximum total resistance in water exit/entry can be 46%/64% of gravity. Finally, a two-layer feed-forward network with six sigmoid hidden neurons and linear output neurons is used for machine learning training. The training results show that using experimental data and a machine learning method, the trans-media resistance of HAUV can be accurately predicted within a certain range. • Hydrodynamic experiments are conducted to determine the resistance of multi-rotor HAUVs during water exit/entry. • The trans-media resistance of multi-rotor HAUVs, particularly the impact of the arms, is detailly analyzed. • Experimental method combined with machine learning can predict the trans-media resistance of HAUV accurately. [ABSTRACT FROM AUTHOR]

Abstract: One-dimensional (1D) materials can increase mechanical properties along the long axis of the reinforcement for the composites because of the transfer of stress across the reinforcement-matrix interfaces parallel with the load. In this study, 1D hexagonal-prism-like ZrB2 particles were synthesized by a sol–gel route using zirconium n-propoxide, boric acid, acetic acid, and fructose. Fructose acted as both a modifier and a carbon source for carbothermal reduction reaction. For comparison purposes, both nascent state gel and aged gel were used to clarify the aging-time-dependent mechanism for ZrB2 synthesis. As a result, a single phase ZrB2 could only be obtained from the aged gel with the optimal ratios (by mol.) of 1.2 and 5 for both fructose and acetic acid to zirconium n-propoxide, respectively, reduced at an optimal temperature of 1550°C for 2h. Additionally, it revealed a perfect hexagonal-prism-like morphology for the ZrB2 particles with a uniform size and shape distribution, and average particle size of ca. 0.8μm in diameter of excircle of the hexagonal cross-section. [Copyright &y& Elsevier]

Abstract: We consider a modified collision branching process incorporating with both independent immigration and instantaneous resurrection. The existence criterion of the process is firstly considered, and also we use the resolvent decomposition theorem to prove that there is a unique CBP-IIR. [Copyright &y& Elsevier]

Abstract: Firstly, an amorphous precursor of hydrous nano-ZrO2–WO3 powder was precipitated by a co-precipitation method in alcohol-water mixed solvent using ammonia as a precipitator. Then, a mixture of tungsten doped ZrB2 and W2B5 powder was successfully synthesized via a solid-state reaction by borothermal and carbothermal reduction using nanocarbon, amorphous boron powders and as-synthesized amorphous nano-ZrO2–WO3. Furthermore, thermodynamic calculations clarify the above-mentioned reactions may occur. The mass and heat flow of the samples were monitored by thermal analysis. The crystallographic structure was identified by X-ray diffractometry. The size and morphology of the particles were characterized by TEM microscopy. The combined effects of uniformly distributed tungsten and the complex physicochemical changes effectively improved the solid state reactions. [Copyright &y& Elsevier]

Abstract: A facile pathway has been developed to prepare silica-based micro/mesoporous bimodal hybrids with super hydrophobicity. It is the special feature of this pathway that though there are no surfactants introduced during the hydrolysis and polycondensation process, the obtained materials exhibit high specific surface areas, high porosity and bimodal structure. Actually, polymethylhydrosiloxane (PMHS), one of the silica sources, assembles itself into a special conformation and plays the role of a structure-directing agent that leads to the formation of the micro/mesophases. Thus, it is thought this novel protocol might be a profitable complement to those methods previously reported for the preparation of porous materials. [Copyright &y& Elsevier]

Abstract: Mesostructured AlSBA-15-SO3H materials with various Si/Al ratios were prepared by a one-pot method and characterized by XRD, N2 adsorption, NH3-TPD and Si, Al MAS-NMR techniques. With the incorporation of Al into SBA-15-SO3H, the total acid sites substantially increased. Such materials showed high activity in the esterification of dimethyl carbonate (DMC) with salicylic acid (SA), and the selectivity of methyl salicylate was correlated with the Bronsted acidity of the catalysts. [Copyright &y& Elsevier]

Novel sandwich-like structured zinc sulfide (ZnS)/octylamine (OA) hybrid nanosheets with exclusively sheet-like morphology were synthesized for the first time via a mild hydrothermal route using OA as structure-directing agent. The as-synthesized products were characterized by the X-ray diffraction, transmission electron microscopy, scan electron microscopy, energy dispersive analyses of X-rays, thermogravimetric analysis, and ultraviolet and visible absorption spectroscopy. The results showed that OA molecules were intercalated between wurtzite ZnS layers. As revealed from optical absorption measurements, the hybrid nanosheets exhibits strong quantum confinement effect with a great blue shift in the band gap. [Copyright &y& Elsevier]