Effects of Fluorescent Pair on the Kinetics of DNA Strand Displacement Reaction

Fluorescent labels are widely used in the characterizations of DNA-based reaction network operations.We systematically studied the effects of commonly used fluorescent pairs on thermal stabilities of signal-substrate duplex and the strand displacement kinetics.It is demonstrated that the modifications of duplex with fluorescent pairs stabilize DNA duplex by up to 3.5°C,and the kinetics of DNA strand displacement circuit is also evidently slowed down.These results highlight the importance of fluorescent pairs towards the kinetic modulation in designing nucleic acid probes and complex DNA dynamic circuits.

Modification of ZnS∶Mn Phosphors by Sb-Doped SnO2 Coating

The coating of ZnS∶Mn by Sb-doped SnO2 using an co-precipitation process was reported. ZnS∶Mn phosphor particles were prepared by solid reaction with ZnS and MnCl2·4H2O. Surface modification of the ZnS∶Mn powders was carried out by coating transparent conductive films of Sb-doped tin oxides which were formed by co-precipitation and heat treatment process. Tin tetrachloride and antimony trichloride were used as the precursor materials for the co-precipitation. The influences of coating molar ratio, Sb concentration in the coatings, annealing temperature and time on the resistivity of coated ZnS∶Mn phosphors were investigated. The optimum co-precipitation processing parameters and annealing conditions were determined. The phosphors were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence(PL) observation and conductance measurements. An improvement in phosphors conductivity was observed while the respective photoluminescence intensity is analogous to the as-prepared ZnS∶Mn phosphors.

纸张涂层热导率的整体参数模型

随着涂布纸用量的不断增加,尤其在数字印刷中的广泛应用,对纸张涂层各项性能的了解成为必须。对纸张涂层热学性能更为详尽的了解可以提高印刷质量、节省电子成像和胶印的工艺成本。其他有关涂布纸的生产工艺也会因此受益。本文基于所用材料及其结构参数,提出了计算纸张涂层热导率模型,探讨了模型中的参数,并对皂石层和碳酸钙层的模型参数进行了对比。

Plasmonic semiconductors for advanced artificial photosynthesis

Plasmonic semiconductors with high free carrier concentration is a class of attractive materials that exhibit metal-like localized surface plasmon resonance(LSPR)for light extinction with tunable features.Their applications in artificial photosynthesis have witnessed considerable advances in terms of the determinants for solar-to-chemical energy conversion efficiency improvement,including light harvesting,charge dynamics as well as surface photochemistry.In this review,we begin with the fundamental introduction to physical principles and unique characters of LSPR excitation in plasmonic semiconductors.The doping strategies for activating LSPR response and the intrinsic merits in artificial photosynthesis are subsequently summarized in detail.In addition,the remaining challenging and future perspectives are briefly outlooked.We anticipate that this review can provide a tutorial guideline to broaden the horizons for plasmonic semiconductors in the exploration of sustainable plasmon-assisted photochemistry application.

Designing macrophage membrane-engineered ruthenium/selenium nanoparticles to block bone metastasis of breast cancer

Bone metastasis along with osteolysis is a common complication of advanced breast cancer,which directly destroys bone function and becomes one of the major causes of cancer-related mortality.It is crucial to develop a new strategy to achieve effective cancer therapy and inhibition of osteolytic bone metastasis.Metal ruthenium(Ru)complexes exhibit therapeutic potential in cancer chemotherapy.However,the clinical applications of Ru complexes were limited by poor bioavailability,lacking targeting,nonspecific distribution.Therefore,in this study,engineering of cell membrane biomimetic modification was used to construct a highly biocompatible nanoplatform with carrying Ru metal complex of RuPOP and Se nanoparticles(SeNPs).Strikingly,the obtained RPSR nanoparticles can efficiently inhibit the proliferation,invasion and migration of breast cancer cells(MDA-MB-231 cells)in vitro.More importantly,RPSR nanoparticles can induce cycle arrest,apoptosis by generating excessive intracellular(reactive oxygen species,ROS)to disrupt the normal redox balance and induce DNA damage in tumor cells.Furthermore,RPSR nanoparticles can also reshape bone microenvironment by regulating selenoproteins to inhibit osteoclasts and avoid osteolytic bone metastasis induced by tumor development.Taken together,this study not only provides an effective cell membrane biomimetic strategy to enhance the shortcomings of metal complexes,but also demonstrates potential clinical significance for the combined treatment of anti-cancer and bone metastasis inhibition.

San copolymer membranes with ion exchangers for Cu(Ⅱ)removal from synthetic wastewater by electrodialysis

Heterogeneous membranes were obtained by using styrene-acrylonitrile copolymer（SAN）blends with low content of ion-exchanger particles（5 wt.%）. The membranes obtained by phase inversion were used for the removal of copper ions from synthetic wastewater solutions by electrodialytic separation. The electrodialysis was conducted in a three cell unit, without electrolyte recirculation. The process, under potentiostatic or galvanostatic control, was followed by p H and conductivity measurements in the solution. The electrodialytic performance,evaluated in terms of extraction removal degree（rd） of copper ions, was better under potentiostatic control then by the galvanostatic one and the highest（over 70%） was attained at8 V. The membrane efficiency at small ion-exchanger load was explained by the migration of resin particles toward the pores surface during the phase inversion. The prepared membranes were characterized by various techniques i.e. optical microscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and differential thermal analysis and contact angle measurements.

Influence of Doping Ions on the Antibacterial Activity of Biomimetic Coating on CoCrMo Alloy

In this study biomimetic fluoridated phosphate doped hydrophilic coatings with various ions on CoCrMo alloy were pre- pared by electrodeposition. Cu and Zn ions were chosen for doping because of their well known antibacterial activity. The struc^xes of the coatings were identified using Fourier-transform Infrared （FTIR） analysis. X-ray Diffraction （XRD） analysis was performed to evaluate crystallite dimensions of the specimen surface. The contact angle was measured in order to establish the hydrophilic/hydrophobic balance and to compute surface energy. All studied samples have a hydrophilic character which is weaken after doping. The time evolution of ions releasing from the coatings was evaluated with an inductively plasma mass spectrometer after immersion in saline phosphate. The hemolytic experiments indicate that except the fluoridated coatings doped with Zn which is slightly hemolytic, all other samples are non hemolytic. The test for antibacterial activity for Staphy- lococcus aureus and Pseudomonas aeruginosa indicated that the fluoridated biomimetic coating doped with various positive ions increases bacterial growth inhibition level significantly. Fluoridated phosphate coating doped with Cu has best antibacterial activity