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51.
Biegerichten in Schrägwalzen-Richtmaschinen und besondere Verhältnisse beim Richten in Zwei-Walzen-Maschinen. Spannungen im Stab, Beanspruchung des Werkstoffs. Ausbildung der plastischen Bereiche, Richtkraft und Antriebsmomente bei freier Biegung und bei Biegung mit Querprägen.  相似文献   
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53.

1 Purpose

Dysfunctional proteostasis, with decreased protein degradation and an accumulation of ubiquitin into aggregated protein inclusions, is a feature of neurodegenerative diseases. Identifying new potential biomarkers in cerebrospinal fluid (CSF) reflecting this process could contribute important information on pathophysiology.

2 Experimental design

A developed method combining SPE and PRM‐MS is employed to monitor the concentration of ubiquitin in CSF from subjects with Alzheimer's disease (AD), Parkinson's disease (PD), and progressive supranuclear palsy (PSP). Four independent cross‐sectional studies are conducted, studies 1–4, including controls (n = 86) and participants with AD (n = 60), PD (n = 15), and PSP (n = 11).

3 Results

The method shows a repeatability and intermediate precision not exceeding 6.1 and 7.9%, respectively. The determined LOD is 0.1 nm and the LOQ range between 0.625 and 80 nm . The CSF ubiquitin concentration is 1.2–1.5‐fold higher in AD patients compared with controls in the three independent AD‐control studies (Study 1, p < 0.001; Study 2, p < 0.001; and Study 3, p = 0.003). In the fourth study, there is no difference in PD or PSP, compared to controls.

4 Conclusion and clinical relevance

CSF ubiquitin may reflect dysfunctional proteostasis in AD. The described method can be used for further exploration of ubiquitin as a potential biomarker in neurodegenerative diseases.  相似文献   
54.
The molecular weight of liquid telechelic polyisobutylene-diolefins was extended with the dithiol glycol-dimercaptoacetate in the presence of UV light. The mechanism of this polymerization was studied by model experiments.  相似文献   
55.
Chelidonium majus L. is a latex-bearing plant used in traditional folk medicine to treat human papillomavirus (HPV)-caused warts, papillae, and condylomas. Its latex and extracts are rich in many low-molecular compounds and proteins, but there is little or no information on their potential interaction. We describe the isolation and identification of a novel major latex protein (CmMLP1) composed of 147 amino acids and present a model of its structure containing a conserved hydrophobic cavity with high affinity to berberine, 8-hydroxycheleritrine, and dihydroberberine. CmMLP1 and the accompanying three alkaloids were present in the eluted chromatographic fractions of latex. They decreased in vitro viability of human cervical cancer cells (HPV-negative and HPV-positive). We combined, for the first time, research on macromolecular and low-molecular-weight compounds of latex-bearing plants in contrast to other studies that investigated proteins and alkaloids separately. The observed interaction between latex protein and alkaloids may influence our knowledge on plant defense. The proposed toolbox may help in further understanding of plant disease resistance and in pharmacological research.  相似文献   
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57.
Development of a motion simulator for testing a mobile surveillance robot   总被引:2,自引:0,他引:2  
A 6-axis motion simulator has been developed, in order to regenerate UGV (unmanned ground vehicle) motion and to test the stabilization system of the mobile surveillance robot that is mounted on the UGV. For developing the 6-axis motion simulator, a simulation-based design procedure was introduced. The 3D geometric model of the motion simulator was created by using 3D CAD modeler ProE. The multibody dynamics model of the motion simulator has also been created by using the general purpose dynamic analysis program ADAMS to validate the design of the motion simulator. Dynamics and control co-simulation model for the motion simulator has been also established for control performance analyses. Actual hardware of the motion simulator has been fabricated based on the proposed simulation based design. Hardware test of the motion simulator has been tried to validate the design. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Oskar Wallrapp was awarded a Ph.D. degree in Mechanical Engineering at the Technical University of Berlin, Germany in 1989. Dr. Wallrapp is currently a Professor in the Department of Precision and Micro Engineering, Muenchen University of Applied Science, Munich, Germany. His research interests are mechanism analysis and design, robotics, and bio-mechanics. Sung-Soo Kim received a Ph.D. degree in Mechanical Engineering from the University of Iowa in 1988. Dr. Kim is currently a Professor in the Department of Mechatronics Engineering at Chungnam National University in Daejeon, Korea. His research interests are real-time multibody formulation and its application to the automotive systems and military robot systems.  相似文献   
58.
Skoglund  Oskar  Leander  John  Karoumi  Raid 《钢结构国际杂志》2020,20(4):1294-1301

The use of high strength steel has the potential to reduce the amount of steel used in bridges and thereby, facilitate a more sustainable construction. A survey of existing bridges built using high strength steel is presented in this paper with emphasis on the Swedish bridge stock. The survey aimed at identifying the steel grades that were used and where in the cross-section they have been used. A case study on the influence of fatigue shows that today’s regulations make it more difficult to use high strength steel in comparison to previous regulations.

  相似文献   
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60.
Application of Reconfigurable CORDIC Architectures   总被引:1,自引:0,他引:1  
Reconfiguration enables the adaption of Coordinate Rotation DIgital Computer (CORDIC) units to the specific needs of sets of applications, hence creating application specific CORDIC-style implementations. Reconfiguration can be implemented at a high level, taking the entire CORDIC unit as a basic cell (CORDIC-cells) implemented in VLSI, or at a low level such as Field-Programmable Gate Arrays (FPGAs). We suggest a design methodology and analyze area/time results for coarse (VLSI) and fine-grain (FPGA) reconfigurable CORDIC units. For FPGAs we implement CORDIC units in Verilog HDL and our object-oriented design environment, PAM-Blox. For CORDIC-cells, multiple reconfigurable CORDIC modules are synthesized with state-of-the-art CAD tools. At the algorithm level we present a case study combining multiple CORDICs based on a geometrical interpretation of a normalized ladder algorithm for adaptive filtering to reduce latency and area of a fully pipelined CORDIC implementation. Ultimately, the goal is to create automatic tools to map applications directly to reconfigurable high-level arithmetic units such as CORDICs.  相似文献   
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