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Effects of Branching Strategy on the Gene Transfection of Highly Branched Poly(β-amino ester)s

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Chinese Journal of Polymer Science 2020年第8期38卷 830-839,I0006页

作者： Yao wang Chen-Fei wang Ming Li De-Zhong Zhou Wei Huang wen-xin wang School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai200240China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049China Department of Dermatology Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin 4Ireland School of Mechanical and Materials Engineering University College DublinDublin 4Ireland

Highly branched poiy(β-amino ester)s(HPAEs)have emerged as one type of the most viable non-viral gene delivery vectors,both in vitro and in ***,the effects of different branching strategies on the gene transfection performance have not yet been ***,using triacrylate(B3)and diamine(B4)as the branching monomers,a series of HPAEs were synthesized via the"A2+B3+C2"and"A2+B4+C2"strategies,*** show that the branching strategy plays a pivotal role in dictating the physiological properties of the HPAE/DNA polyplexes and thus leads to obviously different cell viability and transfection ***,HPAEs synthesized via the"A2+B3+C2"branching strategy are more favorable for DNA transfection than that synthesized via the"A2+B4+C2"*** study may provide new insights into the development of HPAEs based non-viral DNA delivery system.

关键词： Gene therapy Non-viral gene vector Highly branched polymer Branching strategy

Controlled Polymerization of Methyl Methacrylate and Styrene via Cu(0)-Mediated RDRP by Selecting the Optimal Reaction Conditions

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Chinese Journal of Polymer Science 2019年第6期37卷 591-597页

作者： Yong-Peng Miao Jing Lyu Hai-Yang Yong Sigen A Yong-Sheng Gao wen-xin wang School of Materials Science and Engineering Tianjin University Charles Institute of Dermatology School of Medicine University College Dublin School of Mechanical and Materials Engineering University College Dublin

Cu(0)-mediated reversible deactivation radical polymerization(Cu(0)-mediated RDRP) has been demonstrated as an excellent technique to control the polymerization of multiple vinyl monomers(e.g., acrylates, methacrylates, and styrene). However, the complexity of the reaction mechanism and multi-component system nature make it challenging to choose the appropriate conditions and consider the factors of achieving controllable polymerization when switching from one monomer to others with different reactivities. Herein, by polymerizing two examplary monomers: methyl methacrylate(MMA) and styrene via Cu(0)-mediated RDRP under different conditions,we have found that the reaction parameters(e.g., initiator, ligand, solvent, and deactivator) play a crucial role in regulating two equilibriums:(i) mutual conversion of different copper species which determines the relative concentration of Cu(Ⅰ) and Cu(Ⅱ), and(ii)polymerization equilibrium which is the combination of activation/deactivation, propagation and termination processes. We have demonstrated that by taking both the mutual conversion of different copper species and the polymerization equilibrium into account, the optimal reaction conditions could be selected, and the well-controlled Cu(0)-mediated RDRPs of methyl methacrylate and styrene were achieved with narrow molecular weight distributions and predicted molecular weight.

关键词： Cu(0)-mediated RDRP Reaction parameters Polymerization equilibrium Mutual conversion of copper species

Surface Modification With Zinc and Zn-Ni Alloy Compositionally Modulated Multilayer Coatings

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Journal of Iron and Steel Research International 2006年第4期13卷 61-67页

作者： FEI Jing-yin LIANG Guo-zheng xin wen-li wang Wei-kang Department of Applied Chemistry Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

Zinc and Zn-Ni alloy compositionally modulated multilayer （CMM） coatings were electrodeposited on to a steel substrate by the successive deposition of zinc and Zn-Ni alloy sublayers from dual baths. The coated samples were evaluated in terms of the surface appearance, surface and cross-sectional morphologies, as well as corrosion resistance. The microstructural characteristics that were examined using the field emission gun scanning electron microscopy （FEGSEM） confirmed the layered structure, grain refinement of the zinc and Zn-Ni alloy CMM coatings, and revealed the existence of microcracks caused by the internal stress in the thick Zn-Ni alloy sublayers. The corrosion resistance that was evaluated by means of the salt spray test shows that the zinc and Zn-Ni alloy CMM coatings were more corrosion-resistant than the monolithic coatings of zinc or Zn-Ni alloy of the same thickness. The possible reasons for the better protective performance of Zn-Ni/Zn CMM coatings were given on the basis of the analysis on the micrographic features of zinc and Zn-Ni alloy CMM eoatings after the corrosion test. A probable corrosion mechanism of zinc and Zn-Ni alloy CMM coatings was also proposed.

关键词： electrodeposition compositionally modulated multilayer coating Zn-Ni alloy corrosion resistance

Electrical stimulation of the vagus nerve protects against cerebral ischemic injury through an anti-inflammatory mechanism

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Neural Regeneration Research 2015年第4期10卷 576-582页

作者： Yao-xian Xiang wen-xin wang Zhe Xue Lei Zhu Sheng-bao wang Zheng-hui Sun Department of Neurosurgery Chinese PLA General Hospital Department of Radiology Beijing Electric Power Hospit

Vagus nerve stimulation exerts protective effects against ischemic brain injury; however, the underlying mechanisms remain unclear. In this study, a rat model of focal cerebral ischemia was established using the occlusion method, and the right vagus nerve was given electrical stimula-tion （constant current of 0.5 mA; pulse width, 0.5 ms; frequency, 20 Hz; duration, 30 seconds; every 5 minutes for a total of 60 minutes） 30 minutes, 12 hours, and 1, 2, 3, 7 and 14 days after surgery. Electrical stimulation of the vagus nerve substantially reduced infarct volume, improved neurological function, and decreased the expression levels of tumor necrosis factor-α and in-terleukin-6 in rats with focal cerebral ischemia. The experimental findings indicate that the neuroprotective effect of vagus nerve stimulation following cerebral ischemia may be associated with the inhibition of tumor necrosis factor-α and interleukin-6 expression.

关键词： nerve regeneration vagus nerve stimulation cerebral ischemia inflammatory cytokines infarct volume neurological function NSFC grants neural regeneration

Growth Control of High-Performance In As/Ga Sb Type-Ⅱ Superlattices via Optimizing the In/Ga Beam-Equivalent Pressure Ratio

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Chinese Physics Letters 2020年第3期37卷 60-63页

作者： Da-Hong Su Yun Xu wen-xin wang Guo-Feng Song Institute of Semiconductors Chinese Academy of SciencesBeijing 100083 College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049 Beijing Key Laboratory of Inorganic Stretchable and Flexible Information Technology Beijing 100083 Institute of Physics Chinese Academy of SciencesBeijing 100190

The performance of type-Ⅱ superlattice(T2 SL) long-wavelength infrared devices is limited by crystalline quality of T2 SLs. We optimize the process of growing molecular beam epitaxy deposition T2 SL epi-layers on Ga Sb(100)to improve the material properties. Samples with identical structure but diverse In/Ga beam-equivalent pressure(BEP) ratio are studied by various methods, including high-resolution x-ray diffraction, atomic force microscopy and high-resolution transmission electron microscopy. We find that appropriately increasing the In/Ga BEP ratio contributes to improving the quality of T2 SLs, but too large In BEP will much more easily cause a local strain,which can lead to more In Sb islands in the In Sb interfaces. The In Sb islands melt in the In Sb interfaces caused by the change of chemical potential of In atoms may result in the "nail" defects covering the whole T2 SLs, especially the interfaces of Ga Sb-on-In As. When the In/Ga BEP ratio is about 1, the T2 SL material possesses a lower full width at half maximum of +1 first-order satellite peak, much smoother surface and excellently larger area uniformity.

关键词： properties. beam identical

Two new triterpenoid saponins from notoginseng medicinal fungal substance

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Chinese Chemical Letters 2015年第10期26卷 1298-1302页

作者： Wei Xu Cai-Feng Ding xin-wen wang Xiao-Li Liu Zhi-Dong Qiu College of Pharmacy Changchun University of Chinese Medicine

Two new triterpenoid saponins, named ginsenoside Rh10（1） and notoginsenoside ST-6（2）, were isolated from notoginseng medicinal fungal substance. Their structures were elucidated by a combination of 1D and 2D NMR, ... 详细信息

关键词： Notoginseng Triterpenoid ginsenoside Ginsenoside Rh_(10) Notoginsenoside ST-6

Enhanced absorption process in the thin active region of GaAs based p-i-n structure

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Chinese Physics B 2021年第9期30卷 542-546页

作者： Chen Yue Xian-Sheng Tang Yang-Feng Li wen-Qi wang xin-xin Li Jun-Yang Zhang Zhen Deng Chun-Hua Du Hai-Qiang Jia wen-xin wang Wei Lu Yang Jiang Hong Chen Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China University of Academy of Sciences Beijing 100049China Center of Material and Optoelectronics Engineering University of Academy of SciencesBeijing 100049China Songshan Lake Material Laboratory Dongguan 523808China State Key Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

The optical absorption is the most important macroscopic process to characterize the microscopic optical transition in the semiconductor materials. Recently, great enhancement has been observed in the absorption of the active region within a p–n junction. In this paper, Ga As based p–i–n samples with the active region varied from 100 nm to 3 μm were fabricated and it was observed that the external quantum efficiencies are higher than the typical results, indicating a new mechanism beyond the established theories. We proposed a theoretical model about the abnormal optical absorption process in the active region within a strong electric field, which might provide new theories for the design of the solar cells,photodetectors, and other photoelectric devices.

关键词： photoelectric p-n junction absorption coefficient

One-pot and One-step Cu(0)-mediated Reversible-Deactivation Radical Polymerization of N-Isopropylacrylamide(NIPAM) in Water

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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： Zi-Shan Li Jing Lyu Bei Qiu Ying-Hao Li Ruth Foley Ri-Jian Song Melissa Johnson Qiang Geng wen-xin wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP) of the water-soluble monomer Nisopropylacrylamide(NIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(MWs) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP. The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RDRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For NIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher MW poly(Nisopropylacrylamide)(PNIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PNIPAMs with well-defined structure, narrow molecular weight distributions(MWDs) and varied MWs were successfully achieved.

关键词： Cu(0)-mediated RDRP N-isopropylacrylamide Propagation Deactivation Reaction parameters

Numerical and Experimental Study on the Device Geometry Dependence of Performance of Heterjunction Phototransistors

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Chinese Physics Letters 2019年第10期36卷 94-97页

作者： Jin-Lei Lu Chen Yue Xuan-Zhang Li wen-xin wang Hai-Qiang Jia Hong Chen Lu wang Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190 Center of Materials and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049 Songshan Lake Materials Laboratory Dongguan 523808

Heterojunction phototransistors(HPTs)with scaling emitters have a higher optical gain compared to HPTs with normal ***,to quantitatively describe the relationship between the emitter-absorber area ratio(Ae/Aa)and the performance of HPTs,and to find the optimum value of Ae/Aa for the geometric structure design,we develop an analytical model for the optical gain of ***,five devices with different Ae/Aa are fabricated to verify the numerical analysis *** is expected,the measurement result is in good agreement with the analysis model,both of them confirmed that devices with a smaller Ae/Aa exhibit higher optical *** device with area ratio of 0.0625 has the highest optical gain,which is two orders of magnitude larger than that of the device with area ratio of 1 at 3 ***,the dark current of the device with the area ratio of 0.0625 is forty times higher than that of the device with the area ratio of *** calculating the signal-to-noise ratios(SNRs)of the devices,the optimal value of Ae/Aa can be obtained to be *** device with the area ratio of 0.16 has the maximum *** result can be used for future design principles for high performance HPTs.

关键词： emitter transistors value