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Effect of Microwave and He-Ne Laser on Enzyme Activity and Biophoton Emission of Isatis indigotica Fort

Journal of Integrative Plant Biology 2005年第7期47卷 849-855页

作者： Yi-PingCHEN Yong-JunLIU xun-lingwang Zhao-YuREN MingYUE CollegeofEnvironmentSciences Xi＇anUniversityofArchitectureandTechnologyXi＇an710048China CollegeofLifeSciences NorthwestUniversityXi＇an710069China InstituteofPhotonicsandPhoto-Technology NorthwestUniversityXi＇an710069China DepartmentofBiotechnology Xi＇anUniversityofEngineeringScienceandTechnologyXi＇an710048China／／InstituteofEarthEnvironmenttheChineseAcademyofSciencesXi＇an710075China

Abstract: The seed embryos of Isatis indigotica Fort were exposed to He-Ne laser (5.23 mW/mm2, radiated for 5 min) and microwave (1.26 mW/mm2, radiated for 8 s) irradiation to determine the effects of microwave and He-Ne laser pretreatment on enzyme activities, and biophoton emission of cotyledon. Then: (i) changes in the activities of enzymes in I. indigotica cotyledon (such as amylase, transaminase, and proteinase) were measured to investigate the effects of He-Ne laser and microwave pretreatment; and (ii) biophoton emission was measured to determine the speed of cell division and metabolism. Results from these experiments indicated that: (i) the activities of amylase, transaminase, and proteinase of the cotyledon pretreated by He-Ne laser and microwave were significantly increased; and (ii) the intensity of biophoton emission was enhanced significantly by He-Ne laser and microwave irradiation. These changes suggest that He-Ne laser and microwave pretreatment can improve the inner energy of seeds, lead to an enhancement of cotyledon enzymes, and speed up the metabolism of the cell, resulting in significantly increased biophoton emission. Moreover, the mechanism of action of the effects of laser and microwave radiation on the microcalorimetric parameters, enzyme activities, and biophoton emission of seeds is discussed on the basis of the results obtained.

关键词： biophoton emission enzymes activities Isatis indigotica laser microcalorimetric effect microwave

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Wafer-Scale Ag₂S-Based Memristive Crossbar Arrays with Ultra-Low Switching-Energies Reaching Biological Synapses

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NANO-MICRO LETTERS 2025年第1期17卷 1-12页

作者： Zhu, Yuan Nyberg, Tomas Nyholm, Leif Primetzhofer, Daniel Shi, xun Zhang, Zhen Uppsala Univ Dept Elect Engn Div Solid State Elect S-75121 Uppsala Sweden Uppsala Univ Dept Chem Uppsala Sweden Uppsala Univ Dept Phys & Astron Uppsala Sweden Chinese Acad Sci Shanghai Inst Ceram State Key Lab High Performance Ceram & Superfine M Shanghai 200050 Peoples R China

Memristive crossbar arrays (MCAs) offer parallel data storage and processing for energy-efficient neuromorphic computing. However, most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor (CMOS) technology still suffer from substantially larger energy consumption than biological synapses, due to the slow kinetics of forming conductive paths inside the memristive units. Here we report wafer-scale Ag2S-based MCAs realized using CMOS-compatible processes at temperatures below 160 degrees C. Ag2S electrolytes supply highly mobile Ag+ ions, and provide the Ag/Ag2S interface with low silver nucleation barrier to form silver filaments at low energy costs. By further enhancing Ag+ migration in Ag2S electrolytes via microstructure modulation, the integrated memristors exhibit a record low threshold of approximately - 0.1 V, and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological synapses. The low-temperature process also enables MCA integration on polyimide substrates for applications in flexible electronics. Moreover, the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training algorithm. An impressive accuracy of 92.6% in image recognition simulations is demonstrated with the MCAs after the compensation. The demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag2S films Reactive sputter Silver nucleation Ag+ migration Energy-efficient neuromorphic computing

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Effect of junction potential on the EMF of bielectrolyte solid-state sensors

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Journal of University of Science and Technology Beijing 2005年第1期12卷 81-84页

作者： FushenLi HuiXia lingwang YanhongZhang LifenLi MaterialsScienceandEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China

The EMF (electromotive force) expressions of bielectrolyte solid-state sensors derived from classical thermodynamics are not rigorous. They are only applicable in some special situations. In order to expand their applicable scope, they should be derived from irreversible thermodynamics theory. There is a junction potential term in the EMF equations of double solid electrolyte sensors derived from irreversible thermodynamics. The junction potential involves the ion transference numbers and the electron transference numbers of two kinds of solid electrolytes. When the transference numbers of reaction ions in the two solid electrolytes equal 1 only, the junction potential term is zero and two types of EMF equations become the same.

关键词： solid electrolyte sensor electromotive force junction potential transference number

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May Chronic Childhood Constipation Cause Oxidative Stress and Potential Free Radical Damage to Children?

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Biomedical and Environmental Sciences 2004年第3期17卷 266-272页

作者： JI-YUEWANG YE-lingwang SHENG-LIZHOU JUN-FUZHOU SecondAffiliatedHospitalCollegeofMedicine ZhejiangUniversity88JiefangRoadHangzhou310009ZhejiangChina AffiliatedChildren＇sHospital CollegeofMedicineZhejiangUniversity57ZhuganLaneHangzhou310003ZhejiangChina

Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation.

关键词： Chronic childhood constipation Oxidative stress Free radicals Free radical damage Antioxidant Antioxidase

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Purification, Biochemical and Immunological Characterization of Acid Invertases from Apple Fruit

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Journal of Integrative Plant Biology 2005年第1期47卷 50-59页

作者： Qiu-HongPAN Ke-QinZOU Chang-CaoPENG Xiu-lingwang Da-PengZHANG StateKeyLaboratoryofPlantPhysiologyandBiochemistry ChinaAgriculturalUniversityBeijing100094China

: The soluble acid invertase (SAI) and cell wall-bound invertase (CWI) were purified from apple fruit to apparent electrophoretic homogeneity. Based on sequencing, substrate specificity, and immunoblotting assay, the purified enzymes were identified to be two isoforms of acid invertase (β-fructosidase; EC 3.2.1. 26). The SAI and CWI have the same apparent molecular mass with a holoenzyme of molecular mass of 220 kDa composed of 50 kDa subunits. The SAI has a lower Km value for sucrose and higher Km for raffinose compared with CWI. These acid invertases differ from those in other plants in some of their biochemical properties, such as the extremely high Km value for raffinose, no hydrolytic activity for stachyose, and a mixed form of inhibition by fructose to their activity. The antibodies directed against the SAI and CWI recognized, from the crude extract, three polypeptides with a molecular mass of 50, 68, and 30 kDa, respectively. These results provide a substantial basis for the further studies of the acid invertases in apple fruit.

关键词： antiserum cell wall-bound acid invertase fruit Malus domestica purification soluble acid invertase

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Modified Multispectral Space for Color Representation

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Geo-Spatial Information Science 2005年第4期8卷 306-310页

作者： PEI Xiandeng KONG lingwang ZHU Yuanhong HUANG Hao School of Computer Science and Technology Huazhong University of Science and Technology Guanshan Wuhan 430074 China 不详

Conventional multispectral space for color representation is modified by algorithm of cluster analysis and principal component analysis. Results show that the newer modified multispectral space not only keeping the structure of the original space but eliminating zero crosses as well its accuracy of color representation is higher than the conventional.

关键词： multispectral space color representation cluster analysis principal component analysis

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Effect of apoptosis on gastric adenocarcinoma cell line SGC-7901 induced by cis-9,trans-11-conjugated linoleic acid

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World Journal of Gastroenterology 2002年第6期8卷 999-1004页

作者： Jia-RenLiu Bing-QingChen Yan-MeiYang Xuan-lingwang Ying-BenXue FoodScienceandToxicology DepartmentofFoodScienceComellUniversityIthacaNY14853-7201USA PublicHealthColleng HarbinMedicalUniversityHarbin150001HeilongjiangProvinceChina

AIM: To determine the effect of apoptosis on gastric cancer cells (SGC-7901) induced by cis-9, trans-11-conjugated linoleic acid (c9, t11-CLA) and its possible mechanism in the inhibition of cancer cells ***: Using cell culture, flow cytometery and immunocytochemical techniques, we examined the cell growth, frequency of apoptosis and distribution of cell cycle,expression of ki67, bcl-2, Fas, and c-myc of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25,50,100 and 200 μmol@L-1) of c9, t11-CLA for 24h and 48 h,with a negative control (0.1% ethanol).RESULTS: The growth of SGC-7901 cells was inhibited by c9,t11-CLA. Eight days after treatment with various concentrations of c9,t11-CLA, as mentioned above, the inhibition rates were 5.9 %, 20.2 %,75.6 % and 82.4 %, respectively. The frequency of apoptosis on SGC-7901 cells induced by different concentrations of c9, t11-CLA (except for 25 μmol@L-1, 24 h) was significantly greater than that in the negative control (P＜0.01). To further investigate the influence of the cell cycle progression, we found that apoptosis induced by c9, t11-CLA may be involved in blocking the cell cycle of SGC-7901 cells. Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations for various time periods significantly decreased the expressions of ki67 (the expression rates were 18.70-3.20 %, at 24 h and 8.10-0.20 % at 48 h, respectively), bd-2 (4.30-0.15 % at 24 h and 8.05 %-0 at 48 h),and c-myc(4.85-2.20 % at 24 h and 4.75-0.30 % at 48 h) as compared with those in the controls (the expressions of ki67, bcl-2, and c-mycwere 15.1% at 24 h and 13.5 % at 48 h, 6.80 % at 24 h and 8.00 % at 48 h,5.50 % at 24 h and 5.30 % at 48 h, respectively) (P＜0.01),whereas the expressions of Fas were increased (0.60-2.75 %,24 h and 0.45-5.95 %, 48 h).CONCLUSION: The growth and proliferation of SGC-7901 cells are inhibited by cg, t11-CLA via blocking

关键词：胃腺癌细胞系 SGC-7901 亚麻酸衍生物 cis-9 trans-11 诱发凋亡

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RESEARCH ON TURBULENT FLOW WITHIN THE VORTEX PUMP

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Journal of Hydrodynamics 2004年第6期16卷 701-707页

作者： CHENHong-xun ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China

Based on the standard k-ε turbulence model and the RANS equations, thefinite volume method and the SIMPLE algorithm were adopted to carry out the three-dimensionalviscous numerical simulation of the internal flow within a vortex pump in double reference *** to the results of numerical simulation, the internal flow in the vortex pump was analyzed,and the calculated results of blade surface pressure of the impeller were compared withexperimental results. The maximum relative error is 6.6% between calculated value and experimentalvalue of the pump head under operation conditions.

关键词： vortex pump internal flow turbulence

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Application of Self-inhaling Internal Cooling Wheel in Vertical Surface Grinding

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 86-91页

作者： LI xun School of Mechanical Engineering and Automation Beihang University

There is less research on vertical sculptured grinding technology. Especially in high vertical surface grinding process with the cup abrasive wheel, the thermal damage is prone to happen and undermine the grinding surface integrity. This problem limits to improve the grinding efficiency and the grinding ratio greatly. Through the analysis of vertical surface grinding process and features in depth, this paper revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel. Based on the previous research achievements, the grinding experiments on TC4 （Ti-6A1-4V） and GH4169 are carried out utilizing the self-inhaling internal cooling wheel. The experimental results show that the self-inhaling internal cooling wheel can efficiently reduce the grinding surface temperature. Moreover, the inherent mechanism of reducing the grinding temperature using the internal cooling method is revealed. Meanwhile, under the same grinding conditions, the grinding ratio during the experiments on GH4169 using self-inhaling internal cooling method is about 3 times as high as using conventional external cooling method. And the grinding forces can be reduced by about 20%. This research revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel, which provides theoretical basis for the design and application of self-inhaling internal cooling wheel. At the same time, an efficient and non-invasive surface grinding method of TC4 and GH4169 is presented.

关键词： vertical grinding intemal cooling grinding temperature grinding ratio

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Biotechnology smart control over stem cell fate commitment at nanoscale

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Science China Materials 2018年第3期61卷 435-436页

作者： xun Wang Department of Chemistry Tsinghua University

In the landscape of desirable stem-cell-based regeneration,the fate of cell is directed by orchestrated dialog between nanoscale subcellular receptors and biointerfacial niches^([1]).This bottom-up development manner has inspired a great many nanogeometric^([2])and nanotopographic^([3])material-based biointerfaces promising for regenerative *** previous studies shed

关键词： Biotechnology smart control over stem cell fate commitment at nanoscale

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