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4Pi荧光超分辨显微术综述 Review

郝翔, 李依明, 傅爽, 李旸晖, 许迎科, 匡翠方, 刘旭

《工程(英文)》 2022年 第11卷 第4期   页码 146-153 doi: 10.1016/j.eng.2020.07.028

摘要: 回顾这些历程,一个重要的里程碑是基于两个对置物镜的4Pi 显微架构及其超分辨版本的出现。鉴于此,本文综述了4Pi 超分辨显微术的近期进展。总体上,4Pi 超分辨显微镜为透明样品观测提供了一
种能够突破衍射极限、非侵入、各向同性的三维分辨率的技术手段。具体而言,本文针对目标开关和随机开关两个主要4Pi 超分辨显微术版本,讨论了它们的架构、原理、应用和未来发展趋势。

关键词: 荧光超分辨显微术     超分辨成像     4Pi超分辨显微术     isoSTED     4Pi-SMLM    

基于半导体纳米晶体的神经突触器件 Review

步明轩1,2,王越1,2,尹蕾1,2,童周禹1,2,张懿强3,杨德仁1,2,4,5,皮孝东1,2,4,5

《信息与电子工程前沿(英文)》 2022年 第23卷 第11期   页码 1579-1601 doi: 10.1631/FITEE.2100551

摘要:

近年来,人们对信息处理的需求日益增长,脑启发式神经形态器件得到了广泛的关注。突触器件作为一类重要的神经形态器件,在短短几年内迅速升温。在用于制备突触器件的各种材料中,半导体纳米晶体(NCs)因其优异的电学和光学性能而成为首选材料之一。本综述论文首先介绍了基于半导体纳米晶体的突触器件的研究背景及半导体纳米晶体的基本性质。然后,根据器件有源层所用纳米晶体种类的不同,分类介绍了基于纳米晶体的突触器件的最新研究进展。最后,讨论了基于半导体纳米晶体的突触器件目前仍面临的问题和挑战。

关键词: 半导体纳米晶体;突触器件;神经形态计算    

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

《医学前沿(英文)》 2023年 第17卷 第1期   页码 143-155 doi: 10.1007/s11684-022-0929-y

摘要: Gliomas are the most common central nervous system tumours; they are highly aggressive and have a poor prognosis. RGS16 belongs to the regulator of G-protein signalling (RGS) protein family, which plays an important role in promoting various cancers, such as breast cancer, pancreatic cancer, and colorectal cancer. Moreover, previous studies confirmed that let-7c-5p, a well-known microRNA, can act as a tumour suppressor to regulate the progression of various tumours by inhibiting the expression of its target genes. However, whether RGS16 can promote the progression of glioma and whether it is regulated by miR let-7c-5p are still unknown. Here, we confirmed that RGS16 is upregulated in glioma tissues and that high expression of RGS16 is associated with poor survival. Ectopic deletion of RGS16 significantly suppressed glioma cell proliferation and migration both in vitro and in vivo. Moreover, RGS16 was validated as a direct target gene of miR let-7c-5p. The overexpression of miR let-7c-5p obviously downregulated the expression of RGS16, and knocking down miR let-7c-5p had the opposite effect. Thus, we suggest that the suppression of RGS16 by miR let-7c-5p can promote glioma progression and may serve as a potential prognostic biomarker and therapeutic target in glioma.

关键词: RGS16     let-7c-5p     glioma     proliferation     migration    

Xiao Ke Qing improves glycometabolism and ameliorates insulin resistance by regulating the PI3K/Akt pathway

Xiaoqing Li, Xinxin Li, Genbei Wang, Yan Xu, Yuanyuan Wang, Ruijia Hao, Xiaohui Ma

《医学前沿(英文)》 2018年 第12卷 第6期   页码 688-696 doi: 10.1007/s11684-018-0662-8

摘要:

Xiao Ke Qing (XKQ) granule has been clinically used to treat type 2 diabetes mellitus (T2DM) for 10 years in Chinese traditional medication. However, its mechanisms against hyperglycemia remain poorly understood. This study aims to investigate XKQ mechanisms on diabetes and diabetic liver disease by using the KKAy mice model. Our results indicate that XKQ can significantly reduce food and water intake. XKQ treatment also remarkably decreases both the fasting blood glucose and blood glucose in the oral glucose tolerance test. Additionally, XKQ can significantly decrease the serum alanine aminotransferase level and liver index and can alleviate the fat degeneration in liver tissues. Moreover, XKQ can ameliorate insulin resistance and upregulate the expression of IRS-1, PI3K (p85), p-Akt, and GLUT4 in the skeletal muscle of KKAy mice. XKQ is an effective drug for T2DM by ameliorating insulin resistance and regulating the PI3K/Akt signaling pathway in the skeletal muscle.

关键词: XKQ     type 2 diabetes mellitus     KKAy mice     PI3K/Akt pathway     diabetic liver disease    

Ultraviolet-B induced expression of hypoxia-inducible factor 1α, transferrin receptor through EGFR/PI3K

LI Yanhua, BI Zhigang

《医学前沿(英文)》 2007年 第1卷 第1期   页码 79-86 doi: 10.1007/s11684-007-0016-4

摘要: The aim of this research was to explore the effects and signaling pathway of ultraviolet-B (UVB) irradiation on the expression of hypoxia-inducible factor 1α (HIF-1α) and transferrin receptor (TfR). HIF-1α protein was measured by Western blot method. Expressions of epidermal growth factor receptor (EGFR), phosphor-EGF-R and TfR after UVB irradiation were determined with flow cytometry. After UVB irradiation, mRNA levels of HIF-1α and TfR were detected by real time-PCR. Results showed that compared with control groups, UVB was able to induce HIF1α and TfR protein expression in a dose- and time-dependent manner in HaCat cells (<0.05). TfR mRNA was expressed in a dose-dependent manner and reached a peak at the 8th hour in HaCat cells (<0.05) whereas HIF-1α mRNA expression was not affected by UVB treatment (>0.05). The EGFR/PI3K/AKT signaling pathway was required for the induction of HIF-1α and TfR expression induced by UVB. UVB induced activation of EGFR in HaCat cells and EGFR regulated expression of TfR and HIF-1α. EGFR (-/-) MEF did not increase the HIF1 expression following UVB irradiation (>0.05). In contrast, EGFR (+/+) MEF strongly enhanced HIF1α expression after UVB irradiation (<0.05). PD153035, a selective inhibitor of EGFR tyrosine kinase, inhibited the TfR protein expression in UVB-treated cells in a dose-dependent manner (P<0.05). PI3K inhibitors, LY294002 and wortmannin, inhibited HIF-1? and TfR expressions induced by UVB (P<0.05). The DEC1 (-/-) Ha-Cat cells did not increase their TfR and HIF-1α expressions following UVB irradiation (>0.05). In contrast, DEC1 (+/+) HaCat cells strongly enhanced TfR and HIF-1? protein expression after UVB irradiation (P<0.05). We conclude that UVB induces TfR and HIF-1αexpressions via EGFR/PI3K/AKT/DEC1 signaling pathway.

纳卫星微型百叶窗热控技术研究及仿真

杨娟,李运泽,王浚

《中国工程科学》 2008年 第10卷 第7期   页码 169-172

摘要: 在球状纳卫星动态特性模型的基础上,提出了一种模 糊PI 混合控制方法。分别在舱内仪器散热增加和减少的工况下进行控制仿真。

关键词: 纳卫星     微型百叶窗     模糊PI 控制器     仿真    

Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

《能源前沿(英文)》 doi: 10.1007/s11708-023-0910-8

摘要: Polyimide (PI) has emerged as a promising organic photocatalyst owing to its distinct advantages of high visible-light response, facile synthesis, molecularly tunable donor-acceptor structure, and excellent physicochemical stability. However, the synthesis of high-quality PI photoelectrode remains a challenge, and photoelectrochemical (PEC) water splitting for PI has been less studied. Herein, the synthesis of uniform PI photoelectrode films via a simple spin-coating method was reported, and their PEC properties were investigated using melamine as donor and various anhydrides as acceptors. The influence of the conjugate size of aromatic unit (phenyl, biphenyl, naphthalene, perylene) of electron acceptor on PEC performance were studied, where naphthalene-based PI photoelectrode exhibited the highest photocurrent response. This is resulted from the unification of wide-range light absorption, efficient charge separation and transport, and strong photooxidation capacity. This paper expands the material library of polymer films for PEC applications and contributes to the rational design of efficient polymer photoelectrodes.

关键词: polyimide (PI) film     photoelectrochemistry     band structure engineering     aromatic unit    

Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W.

《农业科学与工程前沿(英文)》 2017年 第4卷 第2期   页码 146-154 doi: 10.15302/J-FASE-2017136

摘要: The effect of mulching with straw, white plastic film and black plastic film for improving soil water storage and on the soil properties was examined in a wheat-maize rotation system on Loess soil in northwestern China. All the mulches improved the water storage to some extent and led to warmer soils. However, the organic C and total N contents of the soils declined significantly under the mulches, particularly the plastic film mulches, and this could have long-term detrimental effects on soil quality and the sustainability of the some mulching practices.

关键词: biomass     carbon     mulch     nitrogen     plastic films     soil     straw     water storage    

A 3D porous WP2 nanosheets@carbon cloth flexible electrode for efficient electrocatalytic hydrogen evolution

Mingyu Pi, Xiaodeng Wang, Dingke Zhang, Shuxia Wang, Shijian Chen

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 425-432 doi: 10.1007/s11705-018-1726-7

摘要:

Self-standing porous WP2 nanosheet arrays on carbon fiber cloth (WP2 NSs/CC) were synthesized and used as a 3D flexible hydrogen evolution electrode. Because of its 3D porous nanoarray structure, the WP2 NSs/CC exhibits a remarkable catalytic activity and a high stability. By using the experimental measurements and first-principle calculations, the underlying reasons for the excellent catalytic activity were further explored. Our work makes the present WP2 NSs as a promising electrocatalyst for hydrogen evolution and provides a way to design and fabricate efficient hydrogen evolution electrodes through 3D porous nano-arrays architecture.

关键词: WP2     nanosheet arrays     hydrogen evolution electrocatalyst     flexible electrode    

Performance of PI controller for control of active and reactive power in DFIG operating in a grid-connected

Azzouz TAMAARAT,Abdelhamid BENAKCHA

《能源前沿(英文)》 2014年 第8卷 第3期   页码 371-378 doi: 10.1007/s11708-014-0318-6

摘要: Due to several factors, wind energy becomes an essential type of electricity generation. The share of this type of energy in the network is becoming increasingly important. The objective of this work is to present the modeling and control strategy of a grid connected wind power generation scheme using a doubly fed induction generator (DFIG) driven by the rotor. This paper is to present the complete modeling and simulation of a wind turbine driven DFIG in the second mode of operating (the wind turbine pitch control is deactivated). It will introduce the vector control, which makes it possible to control independently the active and reactive power exchanged between the stator of the generator and the grid, based on vector control concept (with stator flux or voltage orientation) with classical PI controllers. Various simulation tests are conducted to observe the system behavior and evaluate the performance of the control for some optimization criteria (energy efficiency and the robustness of the control). It is also interesting to play on the quality of electric power by controlling the reactive power exchanged with the grid, which will facilitate making a local correction of power factor.

关键词: wind power     doubly fed induction generator (DFIG)     vector control     active power     reactive power     maximum power point tracking (MPPT)    

Precision control system of two-DOF stage with linear ultrasonic motor

ZHANG Hanlei, SHI Yunlai, ZHAO Chunsheng

《机械工程前沿(英文)》 2008年 第3卷 第4期   页码 421-425 doi: 10.1007/s11465-008-0063-9

摘要: Using an appropriate control method, linear ultrasonic motors can be used in applications requiring high position accuracy. In this paper, a closed loop PI control system is designed to achieve high position accuracy during the control of a two-DOF stage driven by linear ultrasonic motors. Two ultrasonic motors are mounted on the stage to generate motion in two orthogonal directions. The PI control algorithm is used to increase the stability and accuracy of position control. The -axis mover covers 30 mm forward and backward in less than 0.3 s settling time and the -axis mover in less than 0.4 s. Experimental results denote that the control strategy proposed in this paper appears to have high efficiency, quick response, and high accuracy.

关键词: settling     position accuracy     PI control     control algorithm     orthogonal    

ZnFe2O4/BiVO4 Z-scheme heterojunction for efficient visible-light photocatalytic

《化学科学与工程前沿(英文)》 2023年 第17卷 第11期   页码 1728-1740 doi: 10.1007/s11705-023-2322-z

摘要: A novel Z-scheme ZnFe2O4/BiVO4 heterojunction photocatalyst was successfully synthesized using a convenient solvothermal method and applied in the visible light photocatalytic degradation of ciprofloxacin, which is a typical antibiotic contaminant in wastewater. The heterostructure of as-synthesized catalysts was confirmed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy characterizations. Compared with the single-phase counterparts, ZnFe2O4/BiVO4 demonstrated considerably enhanced photogenerated charge separation efficiencies because of the Z-scheme transfer mechanism of electrons between the composite photocatalysts. Consequently, the 30% ZnFe2O4/BiVO4 catalyst afforded a degradation rate of up to 97% of 20 mg/L ciprofloxacin under 30 min of visible light irradiation with a total organic carbon removal rate of 50%, which is an excellent activity compared with ever reported BiVO4-based catalysts. In addition, the liquid chromatography-mass spectrometry and quantitative structure-activity relationships model analyses demonstrated that the toxicity of the intermediates was lower than that of the parent ciprofloxacin. Moreover, the as-synthesized ZnFe2O4/BiVO4 heterojunctions were quite stable and could be reused at least four times. This study thus provides a promising Z-scheme heterojunction photocatalyst for the efficient removal and detoxication of antibiotic pollutants from wastewater.

关键词: ZnFe2O4/BiVO4     Z-scheme heterojunction     photocatalytic degradation     ciprofloxacin    

Li4SiO4-coated LiNi0.5Mn1.5O4 as the high performance

Shifeng YANG, Wenfeng REN, Jian CHEN

《能源前沿(英文)》 2017年 第11卷 第3期   页码 374-382 doi: 10.1007/s11708-017-0494-2

摘要: The preparation of Li SiO -coated LiNi Mn O materials by sintering the SiO -coated nickel-manganese oxides with lithium salts using abundant and low-cost sodium silicate as the silicon source was reported. The samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was found that a uniform and complete SiO coating layer could be obtained at a suitable pH value of 10, which transformed to a good Li SiO coating layer afterwards. When used as the cathode materials for lithium-ion batteries, the Li SiO -coated LiNi Mn O samples deliver a better electrochemical performance in terms of the discharge capacity, rate capability, and cycling stability than that of the pristine material. It can still deliver 111.1 mAh/g at 20 C after 300 cycles, with a retention ratio of 93.1% of the stable capacity, which is far beyond that of the pristine material (101.3 mAh/g, 85.6%).

关键词: lithium-ion batteries     cathode material     LiNi0.5Mn1.5O4     lithium-ion conductor     coating    

Enhanced debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) by zero-valent zinc with ascorbic

Chaojin Jiang, Xiaoqian Jiang, Lixun Zhang, Yuntao Guan

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-020-1224-2

摘要: Highly efficient debromination of BDE-47 was achieved in the ZVZ/AA system. BDE-47 debromination by the ZVZ/AA can be applied to a wide range of pH. AA inhibits the formation of (hydr)oxide and accelerates the corrosion of ZVZ. Reduction mechanism of BDE-47 debromination by the ZVZ/AA system was proposed. A new technique of zero-valent zinc coupled with ascorbic acid (ZVZ/AA) was developed and applied to debrominate the 2,2′,4,4′-Tetrabromodiphenyl ether (BDE-47), which achieved high conversion and rapid debromination of BDE-47 to less- or non-toxic forms. The reaction conditions were optimized by the addition of 100 mg/L ZVZ particles and 3 mmol/L AA at original solution pH= 4.00 using the solvent of methanol/H2O (v:v= 4:6), which could convert approximately 94% of 5 mg/L BDE-47 into lower-brominated diphenyl ethers within a 90 min at the ZVZ/AA system. The high debromination of BDE-47 was mainly attributed to the effect of AA that inhibits the formation of Zn(II)(hydr)oxide passivation layers and promotes the corrosion of ZVZ, which leads to increase the reactivity of ZVZ. Additionally, ion chromatography and gas chromatography mass spectrometry analyses revealed that bromine ion and lower-debromination diphenyl ethers formed during the reduction of BDE-47. Furthermore, based on the generation of the intermediates products, and its concentration changes over time, it was proposed that the dominant pathway for conversion of BDE-47 was sequential debromination and the final products were diphenyl ethers. These results suggested that the ZVZ/AA system has the potential for highly efficient debromination of BDE-47 from wastewater.

关键词: 2     2′     4     4′-tetrabromodiphenyl ether (BDE-47)     Ascorbic acid     Reductive debromination     Zero-valent zinc    

Knockdown of RFC4 inhibits the cell proliferation of nasopharyngeal carcinoma and

《医学前沿(英文)》 2023年 第17卷 第1期   页码 132-142 doi: 10.1007/s11684-022-0938-x

摘要: Nasopharyngeal carcinoma (NPC) is a malignant tumor that mainly occurs in East and Southeast Asia. Although patients benefit from the main NPC treatments (e.g., radiotherapy and concurrent chemotherapy), persistent and recurrent diseases still occur in some NPC patients. Therefore, investigating the pathogenesis of NPC is of great clinical significance. In the present study, replication factor c subunit 4 (RFC4) is a key potential target involved in NPC progression via bioinformatics analysis. Furthermore, the expression and mechanism of RFC4 in NPC were investigated in vitro and in vivo. Our results revealed that RFC4 was more elevated in NPC tumor tissues than in normal tissues. RFC4 knockdown induced G2/M cell cycle arrest and inhibited NPC cell proliferation in vitro and in vivo. Interestingly, HOXA10 was confirmed as a downstream target of RFC4, and the overexpression of HOXA10 attenuated the silencing of RFC4-induced cell proliferation, colony formation inhibition, and cell cycle arrest. For the first time, this study reveals that RFC4 is required for NPC cell proliferation and may play a pivotal role in NPC tumorigenesis.

关键词: nasopharyngeal carcinoma     WGCNA     RFC4     proliferation    

标题 作者 时间 类型 操作

4Pi荧光超分辨显微术综述

郝翔, 李依明, 傅爽, 李旸晖, 许迎科, 匡翠方, 刘旭

期刊论文

基于半导体纳米晶体的神经突触器件

步明轩1,2,王越1,2,尹蕾1,2,童周禹1,2,张懿强3,杨德仁1,2,4,5,皮孝东1,2,4,5

期刊论文

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

期刊论文

Xiao Ke Qing improves glycometabolism and ameliorates insulin resistance by regulating the PI3K/Akt pathway

Xiaoqing Li, Xinxin Li, Genbei Wang, Yan Xu, Yuanyuan Wang, Ruijia Hao, Xiaohui Ma

期刊论文

Ultraviolet-B induced expression of hypoxia-inducible factor 1α, transferrin receptor through EGFR/PI3K

LI Yanhua, BI Zhigang

期刊论文

纳卫星微型百叶窗热控技术研究及仿真

杨娟,李运泽,王浚

期刊论文

Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

期刊论文

Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W.

期刊论文

A 3D porous WP2 nanosheets@carbon cloth flexible electrode for efficient electrocatalytic hydrogen evolution

Mingyu Pi, Xiaodeng Wang, Dingke Zhang, Shuxia Wang, Shijian Chen

期刊论文

Performance of PI controller for control of active and reactive power in DFIG operating in a grid-connected

Azzouz TAMAARAT,Abdelhamid BENAKCHA

期刊论文

Precision control system of two-DOF stage with linear ultrasonic motor

ZHANG Hanlei, SHI Yunlai, ZHAO Chunsheng

期刊论文

ZnFe2O4/BiVO4 Z-scheme heterojunction for efficient visible-light photocatalytic

期刊论文

Li4SiO4-coated LiNi0.5Mn1.5O4 as the high performance

Shifeng YANG, Wenfeng REN, Jian CHEN

期刊论文

Enhanced debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) by zero-valent zinc with ascorbic

Chaojin Jiang, Xiaoqian Jiang, Lixun Zhang, Yuntao Guan

期刊论文

Knockdown of RFC4 inhibits the cell proliferation of nasopharyngeal carcinoma and

期刊论文