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Thermodynamic analysis of carbon migration in W1-1.0C steel in plasma surface chromizing

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Journal of University of Science and Technology Beijing 2006年第2期13卷 131-134页

作者： Chengzhong Chi zhiyong he Yuan Gao Zhong Xu College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 China

W 1-1.0C steel was chromized at 1173 K with double glow plasma surface alloying process, and the distribution of Fe, Cr, and C contents in the chromized layer was measured using glow discharge spectrum analysis （GDA）. The behavior and mechanism of carbon migration during the formation of chromized layer were studied through thermodynamic analysis and calculation. The gradient of carbon chemical potential was regarded as the driving force of carbon migration. An equation was derived to describe the carbon content varying with the chromium content within the carbon-rich region. The calculated results from the equation approximated closely to the experimental ones.

关键词： carbon steel chromizing thermodynamic analysis surface alloying carbon migration

An Encoder with Speed over 40Gbps for RC LDPC Codes with Rates Up to 0.96

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Chinese Journal of Electronics 2016年第5期25卷 921-927页

作者： he zhiyong ZHAO Qiang XU Hushan CUI Wenjuan LUO Yuxi Institute of Modern Physics Chinese Academy of Sciences

We propose a class of Rate-compatible(RC) Low-density parity-check(LDPC) codes with a very wide range of code rates. To widen the range of rates, we have developed an optimal transmission scheme to push the upper bound of code rates to 0.96. Characterized by a parity check matrix in a dual-diagonal form, the proposed RC LDPC code can be encoded in linear time. Constructed from shifted identity sub-matrices, the proposed codes are particularly well-suited for the high-speed implementation of parallel encoders. Furthermore, the encoder can be implemented efficiently with several left circular shifters and XOR gates. To maximize the encoding speed, we have proposed a q-parallel encoder architecture, where q is the size of each sub-matrix. The implementation results into Field programmable gate array(FPGA) devices indicate that a72-parallel encoder for the proposed RC LDPC code with a code rate from 0.5 to 0.96 is capable of reaching a speed of 42 Gigabits per second(Gbps) using a clock frequency of 300 MHz.

关键词： Low-density parity-check codes(LDPC) High-speed encoder Field programmable gate array(FPGA) implementation

Enantioselective Diels-Alder reactions with left-handed G-quadruplex DNA-based catalysts

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Chinese Chemical Letters 2021年第5期32卷 1701-1704页

作者： Kun Chen zhiyong he Wei Xiong Chun-Jiang Wang Xiang Zhou College of Chemistry and Molecular Sciences Key Laboratory of Biomedical Polymers of Ministry of EducationWuhan UniversityWuhan 430072China

Since the discovery of left-handed G-quadruplex(L-G4)structure formed by natural DNA,there has been a growing interest in its potential *** study utilised it to catalyse enantioselective Diels-Alder reactions,considering its different optical rotation compared to an ordinary *** was determined that when L-G4 was used with a combination of copper(Ⅱ)ions,there was a good enantioselectivity(-52%ee)without further addition of *** further consideration was given by adding G4 ligands,G4 was further stabilised,even obtaining a better enantioselectivity(up to-80%ee).Moreover,when using ligands that have regulatory effects on G4,the ee value can be *** this work,a minimal left-handed G4 was reported.A follow-up study was also con ducted,which recovers that the minimal left-handed G4 remains its catalytic effect and enantioselectivity,but is not so effective as the former *** indicates that a complete G4 structure is relatively conducive to chiral catalysis.

关键词： Diels-Alder reaction Left-handed G-quadruplex Asymmetric catalysis Enantioselectiv ity G-quadruplex ligand

pH-controlled DNAzymes： Rational design and their applications in DNA-machinery devices

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Nano Research 2016年第10期9卷 3084-3092页

作者： Yuqi Chen Yanyan Song zhiyong he Zijing Wang Wenting Liu FuanWang Xiaolian Zhang Xiang Zhou College of Chemistry and Molecular Sciences The Institute for Advanced Studies Wuhan University Wuhan 430072 China School of Medicine Wuhan University Wuhan 430071 China

The availability and reliability of strategies for molecular biosensing over a finely adjustable dynamic range is essential to enhance the understanding and control of vital biological process. To expand the versatility and utility of nucleic acid- related enzymes, we demonstrated a rational approach to acquiring tunable, pH-dependent deoxyribozymes （DNAzymes） with catalytic activities and response sensitivities that can be tuned through a simple change in solution pH. To do this, we capitalized upon the pH dependence of Hoogsteen interactions and designed i-motif- and triplex-based DNAzymes that can be finely regulated with high precision over a physiologically relevant pH interval. The modified DNAzymes are dependent upon pH for efficient cleavage of substrates, and their catalytic performance can be tuned by regulating the sequence of inserted i-motif/triplex structures. The principle of tunable, pH-dependent DNAzymes provides the opportunity to engineer pH-controlled DNA-machinery devices with unprecedented sensitivity to pH changes. For example, we constructed a DNA-walker device, the stepping rate of which could be adjusted by simply modulating solution pH within an interval of 5.6 to 7.4, as well as a DNA tetrahedron that can be opened at pH 6.4 and kept closed at pH 7.4. The potential of this approach is not limited to serve as pH-dependent devices, but rather may be combined with other elements to expand their practical usefulness.

关键词： pH iMNAzyme TNAzyme DNA walker DNA tetrahedron

Systematic investigation of bioorthogonal cellular DNA metabolic labeling in a photo-controlled manner

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Chinese Chemical Letters 2020年第5期31卷 1104-1108页

作者： Shaokang Jia Shixi Yang Huimin Ji Shuang Peng Kun Chen zhiyong he Xiang Zhou College of Chemistry and Molecular Sciences Key Laboratory of Biomedical Polymers of Ministry of EducationWuhan UniversityWuhan 430072China

Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological *** bond-cleavage type and position of biomolecular remain a great challenge,which determines the metabolic pathway of the targets in living *** we designed two linkages of methylene and carbonyl group attached the N-3 position of the 5-ethynyl-2’-deoxyuridine(EdU)base or the oxygen atom at deoxyribose 3’position to a photocaging group,which would be cleaved by irradiation with 365 nm ultraviolet *** derivatives linked by methylene at the N-3 position had better photodecage efficiency and stability in the absence of *** paper provides a strategy for studying the nucleoside metabolic pathways in cells,which can easily and conveniently evaluate the effect of the position and type of the *** developed strategy affords a reference for controlling spatial and temporal metabolism of small-molecule drugs,allowing direct manipulation of intact cells under physiological conditions.

关键词： DNA metabolic labeling Bioorthogonal chemistry Photocage group Modified nucleoside Cell imaging

Effects of fatty acid chain length and degree of unsaturation on the surface activities of monoacyl trehaloses

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Frontiers of Chemical Science and Engineering 2009年第4期3卷 407-412页

作者： Yue-E SUN Wenshui XIA Xueyan TANG zhiyong he Jie CheN State Key Laboratory of Food Science and Technology Jiangnan University1800 Lihu RoadWuxi 214122China

The surface properties of monoacyl trehaloses with different acyl chains were investigated at 30℃,40℃,50℃,and 60℃.Monoacyl trehaloses were enzymatically synthesized and purified with silica gel column chromatography and semi-preparative high-performance liquid chromatography(HPLC),and the purity of products was identified by mass spectrometry(MS)and nuclear magnetic resonance(NMR).The surface tension of monoacyl trehalose in pure water was measured using Doüy ring method at different *** critical micelle concentrations(CMC),surface tension at the CMC,γCMC,and residual area per molecule,a,were estimated from the *** CMC value of unsaturated monoacyl trehalose was affected by both the degree of unsaturation and the acyl chain length,and the effect of chain length on the CMC value was much stronger than that of the unsaturation ***,there was no significant dependency of theγCMC value and a values on the chain length or the unsaturated degree.

关键词： monoacyl trehalose surface properties degree of unsaturation critical micelle concentration

Processing stage-guided effects of spices on the formation and accumulation of heterocyclic amines in smoked and cooked sausages

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Food Bioscience 2022年第3期47卷 1378-1384页

作者： Diaodiao Yang zhiyong he Zhaojun Wang Qin Fang Fatih Oz Jie Chen Maomao Zeng State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi214122China International Joint Laboratory on Food Safety Jiangnan UniversityWuxi214122China Department of Food Engineering Faculty of AgricultureAtaturk University25240ErzurumTurkey

heterocyclic amines (HAs) could be generated though sausage *** results showed that garlic,black pepper,chili inhibited the formation of HAs (584.29 ng/g,613.11 ng/g,677.23 ng/g) whereas ginger and Sichuan pepper intensified (965.66 ng/g,916.59 ng/g) compare with control sausage 863.86 ng/***,the study showed that garlic,black pepper,chilli all inhibited the formation of total HAs at stage of raw,drying,baking and steaming and had different inhibitory effect at every *** pepper had the best inhibitory effect across four stages and inhibition rate reached 65%,69%,66%,84% after each *** was the only one had inhibitory effect on both free and protein-bound HAs at every stage and inhibition rate about free and protein-bound HAs reached 38% and 76% in finished *** certain spices properly during processing would be helpful to obtain fewer HAs in sausage.

关键词： heterocyclic amine Spices Sausage processing UPLC-MS/MS

Rho/Rock signal transduction pathway is required for MSC tenogenic differentiation

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Bone Research 2015年第3期3卷 173-181页

作者： Edward Maharam Miguel Yaport Nathaniel L Villanueva Takintope Akinyibi Damien Laudier zhiyong he Daniel J Leong Hui B Sun Leni and Peter W.May Department of Orthopedics Icahn School of Medicine at Mount Sinai Departments of Orthopedic Surgery Albert Einstein College of Medicine Radiation Oncology Albert Einstein College of Medicine

Mesenchymal stem cell （MSC）-based treatments have shown promise for improving tendon healing and repair. MSCs have the potential to differentiate into multiple lineages in response to select chemical and physical stimuli, including into tenocytes. Cell elongation and cytoskeletal tension have been shown to be instrumental to the process of MSC differentiation. Previous studies have shown that inhibition of stress fiber formation leads MSCs to default toward an adipogenic lineage, which suggests that stress fibers are required for MSCs to sense the environmental factors that can induce differentiation into tenocytes. As the Rho/ROCK signal transduction pathway plays a critical role in both stress fiber formation and in cell sensation, we examined whether the activation of this pathway was required when inducing MSC tendon differentiation using rope-like silk scaffolds. To accomplish this, we employed a loss-of-function approach by knocking out ROCK, actin and myosin （two other components of the pathway） using the specific inhibitors Y-27632, Latrunculin A and blebbistatin, respectively. We demonstrated that independently disrupting the cytoskeleton and the Rho/ ROCK pathway abolished the expression of tendon differentiation markers and led to a loss of spindle morphology. Together, these studies suggest that the tension that is generated by MSC elongation is essential for MSC teno-differentiation and that the Rho/ROCK pathway is a critical mediator of tendon differentiation on rope-like silk scaffolds.

关键词： MSCs Figure Rho/Rock signal transduction pathway is required for MSC tenogenic differentiation

Effect of exogenous free N^(ε)-(carboxymethyl)lysine on diabetes-associated cognitive dysfunction:neuroinflammation,and metabolic disorders

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Food Science and Human Wellness 2024年第5期13卷 2970-2981页

作者： Huang Zhang Lan Mo Xi Chen Mei Li Maiquan Li Yang Xu Maomao Zeng zhiyong he Qingwu Shen Jie Chen Wei Quan College of Food Science and Technology Hunan Agricultural UniversityChangsha 410128China henan University of Animal Husbandry and Economy Zhengzhou 450046China College of Food Science and Engineering Northwest A&F UniversityYangling 712100China State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China

Diabetes-associated cognitive dysfunction has already been attracted considerable *** glycation end products(AGEs)from daily diets are thought to be a vital contributor to the development of this ***,the effect of one of the best-characterized exogenous AGEs N^(ε)-(carboxymethyl)lysine(CML)on cognitive function is not fully *** the present study,diabetical Goto-Kakizaki(GK)rats were treated with free CML for *** was found that oral consumption of exogenous CML significantly aggravated diabetes-associated cognitive dysfunction in behavioral *** details,exogenous CML increased levels of oxidative stress,promoted the activation of glial cells in the brain,up-regulated the release of inflammatory cytokines interleukin-6,inhibited the protein expression of the brain-derived neurotrophic factor and thus led to ***,exogenous CML promoted the amyloidogenesis in the brain of GK rats,and inhibited the expression of ***,several tricarboxylic acid cycle and glutamate-glutamine/γ-aminobutyric acid cycle intermediates including pyruvate,succinic acid,glutamine,glutamate were significantly changed in brain of GK rats treated with exogenous free *** conclusion,exogenous free CML is a potentially noxious compounds led to aggravated diabetes-associated cognitive dysfunction which could be possibly explained by its effects on neuroinflammation,energy and neurotransmitter amino acid homeostasis.

关键词： Diabetes Cognitive dysfunction N^(ε)-(carboxymethyl)lysine Neuroinflammation Metabolomic