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21.
Interoperability of Design Intent in Integrated Product and Process Design   总被引:1,自引:0,他引:1  
Concurrent engineering is currently an overwhelming t rend in product development since it takes the down-stream product development issues and product life-cycle issues into consideration in up-front design pro cess. At this stage, evaluation, verification and validation of design concepts and design schemes is critical to the right-to-market product development. I dentification and extraction of design intent from the part digital mock-ups in different data formats and created in different CAD syste...  相似文献   
22.
M Maden  D E Ong  D Summerbell  F Chytil 《Nature》1988,335(6192):733-735
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A facile and green preparation of high surface area activated carbons with mixed microporosity and mesoporosity from durian shell waste is reported in this work. The pore structure and surface chemistry of the parent carbon were modified by the combination of ultrasonication and microwave irradiation techniques. The effects of temperature and time in the ultrasonication treatment and power output and time in the microwave irradiation were studied. The electrochemical performance of carbon electrodes for supercapacitors was tested by cyclic voltammeter (CV) and galvanostatic charge–discharge. The results show that the capacitive energy storage of electrodes is critically dependent on the microporosity and surface chemistry of activated carbons. The highest electrode capacitance in this work was 103.6 F/g that prepared from activated carbon modified at an ultrasonication temperature of 323.15 K for 10 min and microwave power output of 900 W for 10 min.  相似文献   
25.
Summary The isolation of several fractions from rat atrial homogenates, by the use of differential and sucrose gradient centrifugation, indicates that the diuretic and natriuretic activity is restricted to the fractions rich in specific granules. Our preliminary results suggest that the active substance is a small peptide which is probably different from the natriuretic substance(s) already known.Supported by a group grant given by the Medical Research Council of Canada to the Multidisciplinary Research Group on Hypertension of the Clinical Research Institute of Montreal.Acknowledgments. The authors thank Suzanne Diebold for technical assistance.  相似文献   
26.
V Giguère  E S Ong  R M Evans  C J Tabin 《Nature》1989,337(6207):566-569
Retinoic acid is known to have dramatic effects on vertebrate limb pattern in development and regeneration, supporting a model in which a gradient of retinoic acid serves as a morphogen to differentially supply positional information to a developing limb. The discovery of a retinoic acid receptor (RAR) and its homology to the steroid and thyroid hormone receptors provided a potential molecular mechanism for limb morphogenesis. One prediction of this model is that the receptor must be expressed in the developing and regenerating limb anlage. We investigated the expression of the RAR in the adult newt, Notophthalmus viridescens, whose amputated limbs are capable of regenerating and upon which retinoic acid can act to alter pattern. We report the cloning of cDNAs encoding a functional newt RAR and the localization of high and uniform levels of RAR mRNA specifically in the regenerating cells that control limb pattern. These results indicate that the morphogenic field is established through differential activation of pre-existing retinoic acid receptors rather than differential expression of the RAR gene.  相似文献   
27.
Identification of a receptor for the morphogen retinoic acid   总被引:37,自引:0,他引:37  
V Giguere  E S Ong  P Segui  R M Evans 《Nature》1987,330(6149):624-629
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28.
Gastric cancer is a major cause of global cancer mortality. We surveyed the spectrum of somatic alterations in gastric cancer by sequencing the exomes of 15 gastric adenocarcinomas and their matched normal DNAs. Frequently mutated genes in the adenocarcinomas included TP53 (11/15 tumors), PIK3CA (3/15) and ARID1A (3/15). Cell adhesion was the most enriched biological pathway among the frequently mutated genes. A prevalence screening confirmed mutations in FAT4, a cadherin family gene, in 5% of gastric cancers (6/110) and FAT4 genomic deletions in 4% (3/83) of gastric tumors. Frequent mutations in chromatin remodeling genes (ARID1A, MLL3 and MLL) also occurred in 47% of the gastric cancers. We detected ARID1A mutations in 8% of tumors (9/110), which were associated with concurrent PIK3CA mutations and microsatellite instability. In functional assays, we observed both FAT4 and ARID1A to exert tumor-suppressor activity. Somatic inactivation of FAT4 and ARID1A may thus be key tumorigenic events in a subset of gastric cancers.  相似文献   
29.
We conducted a three-stage genetic study to identify susceptibility loci for type 2 diabetes (T2D) in east Asian populations. We followed our stage 1 meta-analysis of eight T2D genome-wide association studies (6,952 cases with T2D and 11,865 controls) with a stage 2 in silico replication analysis (5,843 cases and 4,574 controls) and a stage 3 de novo replication analysis (12,284 cases and 13,172 controls). The combined analysis identified eight new T2D loci reaching genome-wide significance, which mapped in or near GLIS3, PEPD, FITM2-R3HDML-HNF4A, KCNK16, MAEA, GCC1-PAX4, PSMD6 and ZFAND3. GLIS3, which is involved in pancreatic beta cell development and insulin gene expression, is known for its association with fasting glucose levels. The evidence of an association with T2D for PEPD and HNF4A has been shown in previous studies. KCNK16 may regulate glucose-dependent insulin secretion in the pancreas. These findings, derived from an east Asian population, provide new perspectives on the etiology of T2D.  相似文献   
30.
以地方文化为载体的多元互动,往往表达在贸易活动,通过文化资源与文化产品支持人与人交往,达到知识、科技与观念等领域的实质文明交流.因此,文明对话,秉持尊重与诚意,开放和欣赏,有助各地相互学习、消化、吸收其他文化体系的内在元素,持续丰富本身主体文化的内涵,生生不息.这是殖民主义入侵前,亚洲民众作为文明多样的互惠共同体,曾经共享的经验.当今各个国家、各种文明互相发现你中有我,相互认识对方欣赏和善用彼此祖辈的文明成果,也会更容易相互真诚与尊重,由此形成良性交往的循环,有助逐步打破文化壁垒和经济保护主义.  相似文献   
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