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Enzymatic Synthesis of a CCk-8 Tripeptide Fragment

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Chinese Journal of Chemistry 2004年第10期22卷 1138-1141页

作者：向华 ECkSTEIN heiner China Pharmaceutical University Nanjing Jiangsu 210009 China Institute of Organic Chemistry University of Tuebingen 72076 Tuebingen Germany

A process for the synthesis of CCk-8 tripeptide H-Gly-Trp-Met-OH catalyzed by immobilized enzyme was re-ported. Enzymes were used for the formation of peptide bonds and the removal of protecting group. Starting with phenylacetyl (PhAc) glycin, N-protected dipeptide PhAc-Gly-Trp-OMe was obtained by coupling PhAc-protected glycine carboxamidomethyl ester (OCam) with Trp-OMe catalyzed by immobilized papain in buffered ethyl acetate. Then the condensation between PhAc-Gly-Trp-OMe and Met-OEtHCl was carried out by immobilized -chy-motrypsin catalysis in solvent free system. Basic hydrolysis was followed getting PhAc-Gly-Trp-Met-OH. The PhAc-group was removed with penicillin G amidase and H-Gly-Trp-Met-OH was obtained in an overall yield of 43.9%. The reaction conversion of tripeptide in solvent free system was strongly affected by the system of basic salts added. The influence of the support materials used to deposit enzymes and structures of acyl donor and nu-cleophile on the reaction was also investigated.

关键词： enzymatic peptide synthesis immobilized enzyme solvent free system tripeptide fragment

Blastoids:a new model for human blastocyst development

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Signal Transduction and Targeted Therapy 2021年第7期6卷 1946-1947页

作者： heiner Niemann Bob Seamark Medizinische Hochschule Hannover(MHH) HannoverGermany Flinders University College of Medicine and Public HealthAdelaideSAAustralia

Recently,two research groups report in Nature1,'2 the ex-vivo production of blastocyst-like structures,called blastoids,that exhibit many of the landmarks in human early development found in viable blastocysts(Fig.1).The formation of a blastocyst is a critical step in early embryo development denoting a key change from the early cleavage stages to ***,the blastocyst,differentiated from the early cleavage stages,is a fluid filled vesicular structure comprised of cells of now,three distinct cell lineages,namely those of the trophoblast,the outer enclosing cell layer,and those of the inner cell mass(ICM)with the hypoblast and epiblast,found in the central fluid filled cavity(the blastocoel).

关键词： filled cavity outer

Sex differences in injury rates in team-sport athletes:A systematic review and meta-regression analysis

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Journal of Sport and Health Science 2022年第1期11卷 104-114页

作者： Astrid Zech karsten Hollander Astrid Junge Simon Steib Andreas Groll Jonas heiner Florian Nowak Daniel P.feiffer Anna Lina Rahlf Department of Human Movement Science and Exercise Physiology Friedrich Schiller University JenaJena 07749Germany MSH Medical School Hamburg Hamburg 20457Germany Swiss Concussion Center Schulthess KlinikZürich 8008Switzerland Department of Human Movement Training and Active AgingHeidelberg UniversityHeidelberg 69117Germany Department of Statistics Technical University of DortmundDortmund 44227Germany Department of Sports and Exercise Medicine Institute of Human Movement ScienceUniversity of HamburgHamburg 20146Germany

Background:Team-sport players have a particularly high injury *** female sex is considered a risk factor,it is still unknown whether female and male team-sport players,in fact,differ in their injury *** aimed to compare injury rates between female and male players by systematically reviewing and meta-analyzing injury surveillance studies of both sexes in order to evaluate sex-specific differences in team-sport ***:Studies that prospectively collected injury data for high-level female and male players(age≥16 years)in basketball,field hockey,football(soccer),handball,rugby(union and sevens),and volleyball were *** reviewers(AZ and ALR)independently assessed study quality and extracted data for overall,match,training,and severe injuries(>28 days’time loss)as well as data regarding injury locations and *** rate ratios(IRRs)were pooled in a meta-analysis,and meta-regression analysis was performed when 10 or more studies were ***:Of 20 studies,9 studies reported injury data from football,3 studies from rugby,3 studies from handball,1 study from basketball,1 study from field hockey,2 studies from volleyball,and 1 study from basketball and field *** overall injuries,the pooled IRR=0.86(95%confidence interval(95%CI):0.76-0.98)indicated significantly more injuries in male than in female *** injury location,the pooled IRR showed higher injury rates in male athletes than in female athletes for upper extremity,hip/groin,thigh,ande foot *** players had a significantly higher rate of anterior cruciate ligament injuries(IRR=2.15,95%CI:1.27-3.62)than male *** significant sex-specific differences in IRR were found for match,training,severe injuries,concussions,or ankle ***:Our meta-analysis provides evidence for sex-specific differences in the injury rates in team *** epidemiological studies including both sexes in sports other than football are needed in order t

关键词： Athletes Female Injuries Male Team sports

Rhodium Catalyzed [2π + 2π + 2π]-Cycloaddition of Alkynyl-Ynamides and Carbon Disulfide to Indolo-Thiopyrane Thiones

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International Journal of Organic Chemistry 2023年第1期13卷 16-39页

作者： Benjamin Dassonneville Felix Hinkel heiner Detert Department of Chemistry Johannes Gutenberg University Mainz Mainz Germany

The synthesis of new indoloannulated thiopyranethiones is reported. The key-step is a rhodium-catalyzed [2 + 2 + 2]-cycloaddition of alkynyl-ynamides with carbon disulfide to close the pyrrole and the thiopyranethione rings simultaneously. A violet idolothiopyrane thione or a mixture of the violet and a red isomer result from [RhCl(C8H14)2]2/3BINAP catalyzed cycloadditions, the regiochemistry is controlled by the substitution pattern on the alkynyl-ynamide.

关键词： Cycloaddition Heterocycles Rhodium Sulfur Alkyne

Research on Face Anti-Spoofing Algorithm Based on Image Fusion

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Computers, Materials & Continua 2021年第9期68卷 3861-3876页

作者： Pingping Yu Jiayu Wang Ning Cao heiner Dintera School of Information Science and Engineering Hebei University of Science and TechnologyShijiazhuang050000China School of Internet of Things and Software Technology Wuxi Vocational College of Science and TechnologyWuxi214028China German-Russian Institute of Advanced Technologies Karan420126Russia

Along with the rapid development of biometric authentication technology,face recognition has been commercially used in many industries in recent ***,it cannot be ignored that face recognition-based authentication techniques can be easily spoofed using various types of attacks such photographs,videos or forged 3D *** order to solve this problem,this work proposed a face anti-fraud algorithm based on the fusion of thermal infrared images and visible light *** normal temperature distribution of the human face is stable and characteristic,and the important physiological information of the human body can be observed by the infrared thermal ***,based on the thermal infrared image,the pixel value of the pulse sensitive area of the human face is collected,and the human heart rate signal is detected to distinguish between real faces and spoofing *** order to better obtain the texture features of the face,an image fusion algorithm based on DTCWT and the improved Roberts algorithm is ***,DTCWT is used to decompose the thermal infrared image and visible light image of the face to obtain high-and low-frequency ***,the method based on region energy and the improved Roberts algorithm are then used to fuse the coefficients of the high-and low-frequency ***,the DTCWT inverse transform is used to obtain the fused image containing the facial texture *** recognition is carried out on the fused image to realize identity *** results show that this algorithm can effectively resist attacks from photos,videos or *** with the use of visible light images alone for face recognition,this algorithm has higher recognition accuracy and better robustness.

关键词： Anti-spoofing infrared thermal images image fusion heart rate detection

Flash X-ray cinematography analysis of dwell and penetration of smallcaliber projectiles with three types of SiC ceramics

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Defence Technology（防务技术） 2016年第3期12卷 277-283页

作者： Elmar STRASSBURGER Steffen BAUER Steffen WEBER heiner GEDON Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institute(EMI)Am Christianswuhr 279400 KandernGermany DLR–German Aerospace Center Institute of Structures and DesignPfaffenwaldring 38-4070569 StuttgartGermany WIWeB–Bundeswehr Research Institute for Materials Fuels and LubricantsInstitutsweg 185435 ErdingGermany

In order to improve the performance of ceramic composite armor it is essential to know the mechanisms during each phase of the projectile–target interaction and their influence on the penetration *** the view on the crater zone and the tip of a projectile penetrating a ceramic is rapidly getting obscured by damaged material,a flash X-ray technique has to be applied in order to visualize projectile *** this purpose,usually several flash X-ray tubes are arranged around the target and the radiographs are recorded on *** EMI a flash X-ray imaging method has been developed,which provides up to eight flash radiographs in one experiment.A multi-anode 450 k V flash X-ray tube is utilized with this *** radiation transmitted through the target is then detected on a fluorescent *** fluorescent screen converts the radiograph into an image in the visible wavelength range,which is photographed by means of a high-speed *** technique has been applied to visualize and analyze the penetration of 7.62 mm AP projectiles into three different types of Si C *** commercial Si C grades and MICASIC(Metal Infiltrated Carbon derived Si C),a C-Si Si C ceramic developed by DLR,have been *** influences,not only of the ceramic but also the backing material,on dwell time and projectile erosion have been *** curves have been determined and their relevance to the ballistic resistance is discussed.

关键词： Ballistic resistance Dwell Flash X-ray cinematography SiC ceramics

Synthesis of CCk-8 Tetrapeptide Fragment by Enzymatic Method

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2003年第3期23卷 234-235,241页

作者：项光亚 heiner Eckstein Pharmacy School Institute of Organic Chemistry

The enzymatic synthesis of a tetrapeptide Phac-Met-Gly-Trp-Met-OEt, a fragment of the cholecystokinin C-terminal octapeptide CCk-8, was reported This fragment was synthesized by coupling Phac-Met-OEt with Gly-OMe, Trp-OMe and Met-OEt successively These three steps were catalyzed by α-chymotrpsin, Papain and α-chymotrpsin respectively The results of FAB-MS showed that all the products had the correct molecular mass

关键词： CCk-8 enzymatic method α-chymotrpsin papain

Numerical Green’s function method:Application to quantifying ground motion variations of M7 earthquakes

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Earthquake Science 2010年第3期23卷 205-214页

作者： Haijiang Wang heiner Igel Frantisek Gallovic School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Earth and Environmental Studies Section Geophysics Ludwig-Maximilians-University Miinchen 80333 Germany Mengcheng National Geophysical Observatory School of Earth and Space Sciences University of Science and Technology of China Mengcheng 233527 China

The concept of ＂numerical Green’s functions＂（NGF or Green’s function database） is developed. The basic idea is： a large seismic fault is divided into subfaults of appropriate size, for which synthetic Green’s functions at the surface （NGF） are calculated and stored. Consequently, ground motions from arbitrary kinematic sources can be simulated, rapidly, for the whole fault or parts of it by superposition. The target fault is a simplified, vertical model of the Newport-Inglewood fault in the Los Angeles basin. This approach and its functionality are illustrated by investigating the variations of ground motions （e.g. peak ground velocity and synthetic seismograms） due to the source complexity. The source complexities are considered with two respects： hypocenter location and slip history. The results show a complex behavior, with dependence of absolute peak ground velocity and their variation on source process directionality, hypocenter location, local structure, and static slip asperity location. We concluded that combining effect due to 3-D structure and finite-source is necessary to quan- tify ground motion characteristics and their variations. Our results will facilitate the earthquake hazard assessment projects.

关键词： numerical Green's function ground motion variation hypocenter location static displacement distribution

Speed Control of Motor Based on Improved Glowworm Swarm Optimization

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Computers, Materials & Continua 2021年第10期69卷 503-519页

作者： Zhenzhou Wang Yan Zhang Pingping Yu Ning Cao heiner Dintera School of Information Science and Engineering Hebei University of Science and TechnologyShijiazhuang050018China School of Internet of Things and Software Technology Wuxi Vocational College of Science and TechnologyWuxi214028China German-Russian Institute of Advanced Technologies Karan420126Russia

To better regulate the speed of brushless DC motors,an improved algorithm based on the original Glowworm Swarm Optimization is *** proposed algorithm solves the problems of poor robustness,slow convergence,and low accuracy exhibited by traditional PID *** selecting the glowworm neighborhood set,an optimization scheme based on the growth and competition behavior of weeds is applied to a single glowworm to prevent falling into a local optimal *** the glowworm’s position is updated,the league selection operator is introduced to search for the global optimal *** the local search ability of the invasive weed optimization with the global search ability of the league selection operator enhances the robustness of the algorithm and also accelerates the convergence speed of the *** mathematical model of the brushless DC motor is established,the PID parameters are tuned and optimized using improved Glowworm Swarm Optimization algorithm,and the speed of the brushless DC motor is *** a Simulink environment,a double closed-loop speed control model was established to simulate the speed control of a brushless DC motor,and this simulation was compared with a traditional PID *** simulation results show that the model based on the improved Glowworm Swarm Optimization algorithm has good robustness and a steady-state response speed for motor speed control.

关键词： PID speed control improved Glowworm Swarm Optimization brushless DC motor