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Mitophagy is the cellular process to selectively eliminate dysfunctional mitochondria, governing the number and quality of mitochondria. Dysregulation of mitophagy may lead to the accumulation of damaged mitochondria, which plays an important role in the initiation and development of tumors. Mitophagy includes ubiquitin-dependent pathways mediated by PINK1/Parkin and non-ubiquitin dependent pathways mediated by mitochondrial autophagic receptors including NIX, BNIP3, and FUNDC1. Cellular mitophagy widely participates in multiple cellular process including metabolic reprogramming, anti-tumor immunity, ferroptosis, as well as the interaction between tumor cells and tumor-microenvironment. And cellular mitophagy also regulates tumor proliferation and metastasis, stemness, chemoresistance, resistance to targeted therapy and radiotherapy. In this review, we summarized the underlying molecular mechanisms of mitophagy and discussed the complex role of mitophagy in diverse contexts of tumors, indicating it as a promising target in the mitophagy-related anti-tumor therapy. [ABSTRACT FROM AUTHOR]

A multifunctional α-MnO2/ZnO--C (MZ) Z-scheme photocatalyst was synthesized by the suit-growth of α-MnO2 on the surface of MOF-5 and pyrolysis of the organic components under certain conditions. The obtained photocatalysts were characterized and the photocatalytic activity was investigated by degrading tetracycline (TC). Especially, the composite with a 15% mass ratio of α-MnO2 (15-MZ) exhibited the best photocatalytic activity for tetracycline under visible light irradiation and the degradation efficiency for TC reached 96.69% within 60 min. The doping of the C element in the ZnO crystal structure formed an intermediate energy level to narrow the band gap of ZnO, which was beneficial for visible light absorption. Also, the construction of a binary synergistic system between ZnO and α-MnO2 resulted in the extension of the light response range and accelerated the transfer of photogenerated carriers. The tests showed that h+, ¹O2, •O2-, and •OH were the main active species and played leading roles in the degradation process. Additionally, the residual C species as an electron-transfer medium were conducive to constructing the Z-scheme heterojunction between ZnO--C and α-MnO2, which provides an interesting approach for designing visible light responsive photocatalysts. [ABSTRACT FROM AUTHOR]

100 nm thick RuMoC films and 5nm thick RuMoC films with Cu capping have been deposited on Si(111) by magnetron co-sputtering with Ru and MoC confocal targets. The samples were subsequently annealed at temperatures ranging from 450 to 650 °C in vacuum at a pressure of 3 x 10-4 Pa to study the annealing effects on the microstructures and properties of RuMoC films for advanced seedless Cu metallization applications. The sheet resistances, residual oxygen contents, and microstructures of the RuMoC films have close correlation with the doping contents of Mo and C, which can be easily controlled by the deposition power ratio of MoC versus Ru targets (DPR). When DPR was 0.5, amorphous RuMoC film (marked as RuMoC II) with low sheet resistances and residual oxygen contents was obtained. The fundamental relationship between the annealing temperatures with the microstructures and properties of the RuMoC films was investigated, and a critical temperature point was revealed at about 550 °C where the components and microstructures of the RuMoC II films changed obviously. Results indicated that below 550 °C, the RuMoC II films remained amorphous due to the well-preserved C-Ru and C-Mo bonds. However, above 550 °C. the microstructures of RuMoC II films transformed from amorphous to nano-composite structure due to the breakage of Ru-C bonds, while the supersaturated solid solution MoC segregated out along the grain boundaries of Ru, thus hindering the diffusion of Cu and O atoms. This is the main mechanism of the excellent thermal stability of the RuMoC films after annealing at high temperatures. The results indicated great prospects of amorphous RuMoC films in advanced seedless Cu metallization applications. [ABSTRACT FROM AUTHOR]

We numerically demonstrate a scheme of optofluidic sorting of nanoparticles on a silicon-based lab-on-a-chip system, with reconfigurable and multilevel sorting size thresholds. Size-dependent sorting of nanoparticles originates from the size-dependent distribution of trapping potential wells, which determines whether a nanoparticle can jump back and forth between parallel waveguides in weakly coupling condition. In numerical modeling, we find that it is easier for larger ones to transfer and the size threshold is power ratio dependent. By setting a thermal tuning ring-assisted Mach–Zehnder interferometer ahead, we can adjust effectively the input power ratio of the parallel waveguides as well as the potential well distribution across them, working as a thermal tuning reconfigurable sorting unit. Consequently, a tree cascaded unit with different thresholds is also presented to be a reconfigurable multilevel sorting unit. The proposed design offers a simple and ultracompact scheme for the reconfigurable and multilevel optofluidic sorting of nanoparticles on thermooptofluidics chip for the first time. [ABSTRACT FROM AUTHOR]

We numerically demonstrate a scheme of optofluidic sorting of nanoparticles on a silicon-based lab-on-a-chip system, with reconfigurable and multilevel sorting size thresholds. Size-dependent sorting of nanoparticles originates from the size-dependent distribution of trapping potential wells, which determines whether a nanoparticle can jump back and forth between parallel waveguides in weakly coupling condition. In numerical modeling, we find that it is easier for larger ones to transfer and the size threshold is power ratio dependent. By setting a thermal tuning ring-assisted Mach'Zehnder interferometer ahead, we can adjust effectively the input power ratio of the parallel waveguides as well as the potential well distribution across them, working as a thermal tuning reconfigurable sorting unit. Consequently, a tree cascaded unit with different thresholds is also presented to be a reconfigurable multilevel sorting unit. The proposed design offers a simple and ultracompact scheme for the reconfigurable and multilevel optofluidic sorting of nanoparticles on thermooptofluidics chip for the first time. [ABSTRACT FROM AUTHOR]

A novel mesoporous MoO2 composite supported on graphene oxide (m-MoO2/GO) has been designed and applied as an efficient epoxidation catalyst. The m-MoO2/GO composite was characterised by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, Brunauer-Emmet-Teller surface area analysis, field emission scanning electron microscopy, and transmission electron microscopy. Compared with pure mesoporous MoO2 (m-MoO2) and amorphous MoO2-graphene oxide (a-MoO2/GO), m-MoO2/GO exhibits the best catalytic activity. The conversion and selectivity for cyclooctene are both over 99% in 6 h. Remarkably, the mesoporous structure in m-MoO2/GO which derives from SiO2 nanospheres endows the catalyst better catalytic performance for long chain olefins: the conversion of methyl oleate can be as high as 82 %. Such a robust catalyst can be easily recycled and reused five times without significant loss of catalytic activity. This novel catalyst is promising in the synthesis of epoxides with a long carbon chain or large ring size. [ABSTRACT FROM AUTHOR]

Atwo-dimensional thin-layer chromatographic fingerprint has been developed on a polyamide plate for the quality control of Helleborus thibetanus Franch. The investigated sample was separated by chloroform-ethyl acetate-methanol (3.0:8.0:4.4, v/v) in the first dimension and isooctane-n-propyl alcohol-water (10:2.5:1.0, v/v) adding 0.28 mol L-1 sodium dodecyl sulfate, a reversed micelle, in the second dimension. The plate was dried in the air at room temperature and examined in ultraviolet (UV) light at λ = 365 nm after development. The two developments were carried out over a distance of 70 mm. The two-dimensional thin-layer chromatographic method was validated in terms of repeatability, stability, and robustness. For fingerprint analysis, nine spots were identified as common spots. Statistical method (canonical correlation analysis) was first used to calculate the degree of similarity between the two-dimensional chromatograms. The proposed method was novel and accurate for the identification and quality evaluation of H. thibetanus Franch. [ABSTRACT FROM AUTHOR]

The novel mesoporous materials containing titanium and manganese, Ti-HMS (50) and Mn-HMS (50) (the number 50 denoting the Si/metal of molar ratio), were synthesized using laurylamine as template at room temperature. They were characterized by a series of techniques including powder XRD, FT-IR, UV–Vis spectroscopy, TEM, TG and Nitrogen physisorption. The results indicated that titanium and manganese had been incorporated into the HMS and both them had a wormhole mesopore structure. It also suggested that Mn2+ and Mn3+ coexisted in the Mn-HMS, Ti4+ in Ti-HMS. Besides, epoxidation of soybean oil over these synthesized catalysts was performed using tert-butyl hydroperoxide (TBHP) as oxidant. An increase in the activity was observed when surface area, pore diameter and hydrophobic nature were increased, which meant more active center reacting with soybean oil (SBO), also could reduce the energy barrier and avoid the oxirane ring opening. Furthermore, the result indicated that Mn-HMS showed a higher selectivity (up to 82.9% for Mn and 51.1% for Ti), but Ti-HMS exhibited a better conversion. The novel mesoporous materials containing titanium and manganese, Ti-HMS (50) and Mn-HMS (50), were synthesized. All catalysts was characterized by XRD, which suggested a single low-angle (100) peak at 2.3° < 2θ < 2.8°, characteristic of HMS materials. It also suggested a decrease in uniformity and crystallinity of the porous structure because of the metal incorporation. Besides, for the epoxidation of soybean oil over these catalysts, Mn-HMS showed a higher selectivity (up to 82.9% for Mn and 51.1% for Ti), but Ti-HMS exhibited a better conversion.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A series of new organometallic catalysts for epoxidized vegetable oils using H2O2 in a biphasic system were investigated. The effect of reaction parameters such as the amount of hydrogen peroxide, reaction time and temperature in the epoxidation of soybean oil are discussed in detail. A selectivity of 83.8% was obtained in 4 h at 60 °C, when [(C18H37)2N(CH3)2]3{PO4[WO(O2)2]4} was used as the catalyst. When methyltrioxorhenium (MTO), imidazole and CH3CN were used as the catalyst, adduct, and solvent respectively, a selectivity of 99.90% was achieved in 4 h at 20 °C. The catalytic system was used for the epoxidation of other oils, whose results showed it was active in the epoxidation of long-chain unsaturated compounds. Furthermore, the reaction of H2O2 with methyltrioxorhenium was studied by UV–Vis spectroscopy, which revealed the active peroxorhenium complexes formed during the reaction. Epoxidation of these oils with organometallic compounds occurred through the interactions between the oils unsaturated sites HOMO π(C–C) and the unoccupied peroxo σ*(O–O) orbital. [ABSTRACT FROM AUTHOR]

In this paper nanosized Co3O4/CeO2 was successfully synthesized by a simple hydrothermal method and was applied as catalyst in catalytic ozonation of phenol in solution. The observed results show that nanoparticles have a pleasant special surface. Ozonation experiments indicate that the nanoparticles present a certain catalytic effect on the degradation of phenol and a remarkable acceleration on the chemical oxygen demand removal. Further investigations reveal that a mechanism of solid–liquid interface reactions exists in this system. [ABSTRACT FROM AUTHOR]

In this work, magnesia from natural brucite mineral has been used firstly for catalytic degradation of nitrobenzene and aniline in presence of ozone. Compared with single ozonation, the catalytic ozonation accelerated markedly the degradation of nitrobenzene and aniline. The influences of hydroxyl radical scavengers, pH values, and reaction temperatures on degradation were investigated. It was found that the essential of catalysis was the homogeneous catalysis of hydroxyl ions in water, which accelerated the generation of hydroxyl radicals. As a catalyst, magnesia from natural brucite has supplied an economical and feasible choice for catalytic ozonation of nitrobenzene and aniline in industrial wastewater. [ABSTRACT FROM AUTHOR]

A method of nonaqueous capillary electrophoresis was established for the separation and determination of alanine, phenylalanine, isoleucine and valine after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazol in nonaqueous media. The derivatization and separation conditions were optimized. The optimum derivatization conditions were 70 min for the reaction time, 55 °C for the reaction temperature and 20 mM ammonium acetate in methanol for the derivatization buffer. The most suitable running buffer was composed of 60 mM ammonium acetate, 10% acetonitrile in methanol with a fused-silica capillary column (47 cm × 75 µm i.d.), 20 kV applied voltage and 20 °C capillary temperature. The correlation coefficients were better than 0.995 in the investigated concentration ranges. The relative standard deviation (R.S.D.) (n = 5) of the migration times and peak areas were 2.0–4.3% and 1.9–4.5%, respectively. The method was applied to the determination of four compounds in two compound amino acid injections, with the exception of phenylalanine, the recoveries for the other three compounds ranging between 88–116%. [ABSTRACT FROM AUTHOR]

A novel poly(acryl-p-toluenesulfonamideamidine-p-toluenesulfonylamide) chelating fiber containing S, N and O elements was synthesized from polyacrylonitrile fiber andp-toluenesulfonamide and used for the preconcentration and separation for traces of Ru(III), Rh(III), Au(III) and Pd(IV) ions from waste water and ore sample solution. The synthesis of this fiber was simple and rapid. The results indicate that 100?ng?mL-1 of these ions can be quantitatively enriched by the chelating fiber at a flow rate of 6?mL?min-1 and a pH of 4 and desorbed quantitatively with 20?mL of 6?mol?L-1 HCl and 5% CS(NH2)2 solution at 50?°C (with recovery>?95%). A 50 to 1000-fold excess of Ca2+, Mg2+, Mn2+, Co2+, Fe3+, Cu2+, Zn2+, and Al3+ ions caused little interference in the concentration and determination of the analyzed ions. When the fiber had been reused twenty times, the recoveries of the ions enriched by the fiber were still over 96%. The saturated adsorption capacities of the fiber were in the range of 22-96?mg?g-1. The relative standard deviation (RSD) of the method was between 0.70% and 0.84%. Recoveries of a standard added to actual samples were in range of 95-101%. The results obtained for these ions in real solution samples were basically in agreement with the given values, the average errors being below 5.0%. FT-IR spectra show that the existence of -SO2-Ar, HN=C-NH-, O=C-NH- and -NH-SO2 functional groups are verified in the chelating fiber. The experiments show that the method is rapid, precise, simple and convenient. [ABSTRACT FROM AUTHOR]

Using ammonia and Co(CH3COO)2·4H2O as starting materials, a facile and surfactant-free route to controlled synthesis of Co3O4 nanoparticles was proposed. Co3O4 nanoparticles with average sizes of 3.5, 6, 11, 19 and 70 nm were obtained through adjusting the ethanol amount in the solvent (the ratio of ethanol to water) or the concentration of raw materials. In this process, the presence of enough O2 was crucial for the formation of pure Co3O4 phase. The environmental catalytic properties of as-obtained Co3O4 nanoparticles were investigated. The results indicated their remarkable catalysis for ozonation degradation of phenol, which denoted a promising application as catalyst in waste-water treatment. [ABSTRACT FROM AUTHOR]