The Experts below are selected from a list of 284016 Experts worldwide ranked by ideXlab platform
X G Zheng - One of the best experts on this subject based on the ideXlab platform.
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artificial skin to sense Mechanical Stress by visible light emission
Applied Physics Letters, 1999Co-Authors: T Watanabe, Morito Akiyama, X G ZhengAbstract:The idea and successful practice of a Stress sensor to sense Mechanical Stress by an artificial skin, i.e., self-diagnosis thin film, has been realized, through the fabrication of a high-luminescence thin piezoelectric film which can reproducibly emit strong visible light upon Stressing. The strongest luminescent film consists of nanosized crystallites of ZnS doped with 1.5 at. % Mn, in which Mn acts as the emitting center. The intensity of the emitted luminescence responds to Stress applied directly onto the film or to the underlying material reversibly and reproducibly, so it can be used as an artificial skin to sense Mechanical Stress.
Bertram Schmidt - One of the best experts on this subject based on the ideXlab platform.
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Toolbox for detection of Mechanical and thermo-Mechanical Stress in electronic components
Proceedings of the 2011 34th International Spring Seminar on Electronics Technology (ISSE), 2011Co-Authors: Sebastian Holl, Sören Majcherek, Sören Hirsch, Markus Detert, Bertram SchmidtAbstract:This paper reports the development process of a measurement system for Mechanical Stress detection. A piezoresistive silicon sensor chip is used to convert the inducted Mechanical Stress into a resistance change, measured by a developed resistance analyzer. Aim of our work was to simplify the sensor chip for high flexibility in design and adaption. The sensor chip can easily adapt to a device under test and can be conditioned to perform long-term, in-situ measurements of Mechanical Stress in electronic components and packages. Therefore all sensor intelligence packed in the resistance meter unit. This is controlled by a specialized software program. To increase the measuring accuracy all resistors measured by the Four-Point-Method with modified routing layout. Given that, up to 96 resistive signals can be measured. Though the modular design, the whole system gains high flexibility in respect of the application field.
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An Approach for Characterizing Residual Mechanical Stress Caused by Packaging Processes
MRS Proceedings, 2011Co-Authors: Soeren Hirsch, Bertram SchmidtAbstract:Abstractthis paper reports on a method for estimation and minimization of Mechanical Stress on MEMS sensor and actuator structures due to packaging processes based on flip chip technology. For studying Mechanical Stress a test chip with silicon membranes was fabricated. Finite element method simulation was calculate the Stress profile and to determine the optimum positions for placing the resistor network.
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Development of a Mechanical Stress-analysing-tool to characterize packaging processes
3rd Electronics System Integration Technology Conference ESTC, 2010Co-Authors: Sebastian Holl, Sören Majcherek, Sören Hirsch, Bertram SchmidtAbstract:This paper reports on the development of a measurement system to detect Mechanical Stress caused by packaging processes. A piezoresistiv silicon test chip is used to convert the inducted Mechanical Stress into a resistance change, measured by a developed resistance analyser. The sensor interface is capable to measure a high number of resistors with a high measurement rate. Thus, also rapid proceeding packaging processes can be characterized. Furthermore, the developed software calculates the Stress distribution along the whole die, which includes a compensation of the systematic errors e.g. the temperature dependence of the piezoresistive coefficients.
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Test Chip for Characterization of Mechanical Stress Caused by Packaging Processes
2006 1st Electronic Systemintegration Technology Conference, 2006Co-Authors: Soeren Hirsch, Marc-peter Schmidt, Bertram SchmidtAbstract:This paper reports on a method for estimation and minimization of Mechanical Stress on MEMS sensor and actuator structures due to packaging processes based on flip chip technology. For studying Mechanical Stress a test chip with silicon diaphragms was fabricated. A network of piezo-resistive solid state resistors created by diffusion was used to measure the surface tension pattern between adjacent diaphragms. Finite element method simulation was used to calculate the Stress profile and to determine the optimum positions for placing the resistive network.
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A new device for characterization of Mechanical Stress caused by packaging processes
Smart Structures and Materials 2006: Smart Electronics MEMS BioMEMS and Nanotechnology, 2006Co-Authors: Soeren Hirsch, Bertram SchmidtAbstract:This paper reports on a new method for estimation and minimization of Mechanical Stress on MEMS sensor and actuator structures due to packaging processes based on flip chip technology. For studying Mechanical Stress a test chip with silicon diaphragms was fabricated. A network of piezo-resistive solid state resistors created by diffusion was used to measure the surface tension pattern between adjacent diaphragms. Finite element method simulation was used to calculate the Stress profile and to determine the optimum positions for placing the resistive network.
Shintaro Nomura - One of the best experts on this subject based on the ideXlab platform.
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molecular events caused by Mechanical Stress in bone
Matrix Biology, 2000Co-Authors: Shintaro Nomura, Teruko TakanoyamamotoAbstract:The shape of bone changes as a result of bone remodeling corresponding to physical circumstances such as Mechanical Stress. The tissue which receives the loaded Mechanical Stress most efficiently is bone matrix. Recent studies revealed the function of osteocytes as mechanosensors in the early stage of bone remodeling. Loaded Mechanical Stress is converted to a series of biochemical reactions, and finally activates osteoclasts and osteoblasts to cause bone resorption and formation. Biochemical and molecular biological studies have recently resulted in the identification of the gene of which expression level is changed by Mechanical Stress. Nitric oxide (NO) and cAMP is secreted in response to Mechanical Stress in the immediate early stage. Genes encoding enzymes such as glutamate/aspartate transporter (GLAST), nitric oxide synthetase (NOS) and prostaglandin G/H synthetase (PGHS-2) are identified as Mechanical Stress-responsive. The expression level of IGF-I is enhanced under the control of PTH/PTHrP. The expression of c-fos is increased by loading of Mechanical Stress. AP1, a heterodimer of c-FOS/c-JUN, functions as a transcription factor of downstream gene(s). Elements including AP1 sites, cyclic AMP response elements (CRE) and shear Stress response elements (SSRE) are found in the promoter region of Mechanical Stress-response genes. The enhanced expression of osteopontin (OPN) in the osteocytes of bone resorption sites was demonstrated by in situ hybridization and immunohistochemistry and transdifferentiation of chondrocytes with the abundant expression of BMP-2 and -4 in the process of distraction osteogenesis was observed.
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role of osteopontin in bone remodeling caused by Mechanical Stress
Journal of Bone and Mineral Research, 1999Co-Authors: Kunihiro Terai, Teruko Takanoyamamoto, Yasuo Ohba, Kenji Hiura, Mizuo Sugimoto, Motohiko Sato, Hirohisa Kawahata, Naohiro Inaguma, Yukihiko Kitamura, Shintaro NomuraAbstract:Changes in the number and proportion of osteopontin mRNA (Opn) expressing osteocytes and osteoclasts caused by the Mechanical Stress applied during experimental tooth movement were examined in the present study. Opn expression was detected in the osteocytes on the pressure side at the early stage, and gradually spread to those on the tension side and also to the osteoblasts and bone-lining cells in the alveolar bone. Only 3.3% of the osteocytes located on the pressure side expressed Opn in the interradicular septum of control rats; in contrast, the value was increased to 87.5% at 48 h after the initiation of tooth movement. These results indicate that these cells responded to Mechanical Stress loaded on the bone with expression of the osteopontin gene. Following the increased expression of Opn in these cells, a 17-fold greater number of osteoclasts compared with the control and numerous resorption pits were observed on the pressure side of the alveolar bone. Injection of arginine-glycine-aspartic acid-serine peptide but not that of arginine-glycine-glutamic acid-serine peptide strongly inhibited the increase in the number of osteoclasts. Furthermore, an in vitro migration assay demonstrated the chemotactic activity of osteopontin (OPN) on the precursor of osteoclasts. Our study strongly suggests that OPN is an important factor triggering bone remodeling caused by Mechanical Stress.
Kim Baumann - One of the best experts on this subject based on the ideXlab platform.
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ATR senses Mechanical Stress
Nature Reviews Molecular Cell Biology, 2014Co-Authors: Kim BaumannAbstract:Mechanical Stress activates an ATR pathway at the nuclear envelope that is important for chromatin condensation and nuclear envelope breakdown.
Teruko Takanoyamamoto - One of the best experts on this subject based on the ideXlab platform.
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molecular events caused by Mechanical Stress in bone
Matrix Biology, 2000Co-Authors: Shintaro Nomura, Teruko TakanoyamamotoAbstract:The shape of bone changes as a result of bone remodeling corresponding to physical circumstances such as Mechanical Stress. The tissue which receives the loaded Mechanical Stress most efficiently is bone matrix. Recent studies revealed the function of osteocytes as mechanosensors in the early stage of bone remodeling. Loaded Mechanical Stress is converted to a series of biochemical reactions, and finally activates osteoclasts and osteoblasts to cause bone resorption and formation. Biochemical and molecular biological studies have recently resulted in the identification of the gene of which expression level is changed by Mechanical Stress. Nitric oxide (NO) and cAMP is secreted in response to Mechanical Stress in the immediate early stage. Genes encoding enzymes such as glutamate/aspartate transporter (GLAST), nitric oxide synthetase (NOS) and prostaglandin G/H synthetase (PGHS-2) are identified as Mechanical Stress-responsive. The expression level of IGF-I is enhanced under the control of PTH/PTHrP. The expression of c-fos is increased by loading of Mechanical Stress. AP1, a heterodimer of c-FOS/c-JUN, functions as a transcription factor of downstream gene(s). Elements including AP1 sites, cyclic AMP response elements (CRE) and shear Stress response elements (SSRE) are found in the promoter region of Mechanical Stress-response genes. The enhanced expression of osteopontin (OPN) in the osteocytes of bone resorption sites was demonstrated by in situ hybridization and immunohistochemistry and transdifferentiation of chondrocytes with the abundant expression of BMP-2 and -4 in the process of distraction osteogenesis was observed.
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role of osteopontin in bone remodeling caused by Mechanical Stress
Journal of Bone and Mineral Research, 1999Co-Authors: Kunihiro Terai, Teruko Takanoyamamoto, Yasuo Ohba, Kenji Hiura, Mizuo Sugimoto, Motohiko Sato, Hirohisa Kawahata, Naohiro Inaguma, Yukihiko Kitamura, Shintaro NomuraAbstract:Changes in the number and proportion of osteopontin mRNA (Opn) expressing osteocytes and osteoclasts caused by the Mechanical Stress applied during experimental tooth movement were examined in the present study. Opn expression was detected in the osteocytes on the pressure side at the early stage, and gradually spread to those on the tension side and also to the osteoblasts and bone-lining cells in the alveolar bone. Only 3.3% of the osteocytes located on the pressure side expressed Opn in the interradicular septum of control rats; in contrast, the value was increased to 87.5% at 48 h after the initiation of tooth movement. These results indicate that these cells responded to Mechanical Stress loaded on the bone with expression of the osteopontin gene. Following the increased expression of Opn in these cells, a 17-fold greater number of osteoclasts compared with the control and numerous resorption pits were observed on the pressure side of the alveolar bone. Injection of arginine-glycine-aspartic acid-serine peptide but not that of arginine-glycine-glutamic acid-serine peptide strongly inhibited the increase in the number of osteoclasts. Furthermore, an in vitro migration assay demonstrated the chemotactic activity of osteopontin (OPN) on the precursor of osteoclasts. Our study strongly suggests that OPN is an important factor triggering bone remodeling caused by Mechanical Stress.