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1.
Architecture, engineering, and construction (AEC) global project teamwork is communication intensive and relies heavily on synchronous and asynchronous information and collaboration technologies (ICT). We explore in this paper how an asynchronous ICT, called ThinkTank, reshaped the work practice of design-construction global teams, and how the interaction with this ICT reshaped the purpose and benefits of its use. ThinkTank is a web-based asynchronous collaboration and discussion forum. We introduce the influence diffusion model (IDM) that formalizes the process of identifying the influence of people, messages, and terms mathematically. Discovering who the influence leaders in project teams are can be beneficial and critical from a corporate management perspective, since they can guide or motivate the team towards successful actions and outcomes. We present the ThinkTank-IDM integrated system and its validation with a testbed of 53 AEC global team project archived in ThinkTank over 8 years. 相似文献
2.
Free fatty acids regulate insulin secretion from pancreatic beta cells through GPR40 总被引:32,自引:0,他引:32
Itoh Y Kawamata Y Harada M Kobayashi M Fujii R Fukusumi S Ogi K Hosoya M Tanaka Y Uejima H Tanaka H Maruyama M Satoh R Okubo S Kizawa H Komatsu H Matsumura F Noguchi Y Shinohara T Hinuma S Fujisawa Y Fujino M 《Nature》2003,422(6928):173-176
Diabetes, a disease in which carbohydrate and lipid metabolism are regulated improperly by insulin, is a serious worldwide health issue. Insulin is secreted from pancreatic beta cells in response to elevated plasma glucose, with various factors modifying its secretion. Free fatty acids (FFAs) provide an important energy source as nutrients, and they also act as signalling molecules in various cellular processes, including insulin secretion. Although FFAs are thought to promote insulin secretion in an acute phase, this mechanism is not clearly understood. Here we show that a G-protein-coupled receptor, GPR40, which is abundantly expressed in the pancreas, functions as a receptor for long-chain FFAs. Furthermore, we show that long-chain FFAs amplify glucose-stimulated insulin secretion from pancreatic beta cells by activating GPR40. Our results indicate that GPR40 agonists and/or antagonists show potential for the development of new anti-diabetic drugs. 相似文献
3.
Shinichi GODA Yukio OHSAWA School of Engineering The University of Tokyo - Japan 《系统科学与系统工程学报(英文版)》2007,(4)
Chain reaction bankruptcy is regarded as common phenomenon and its effect is to be taken into account when credit risk portfolio is analyzed.But consideration and modeling of its effect leave much room for improvement.That is mainly because method for grasping relations among companies with limited data is underdeveloped.In this article,chance discovery method is applied to estimate industrial relations that are to include companies' relations that transmit chain reaction of bankruptcy. Time order method and directed KeyGraph are newly introduced to distinguish and express the time order among defaults that is essential information for the analysis of chain reaction bankruptcy.The steps for the data analysis are introduced and result of example analysis with default data in Kyushu, Japan,2005 is presented.The structure estimated by the new method is compared with the structure of actual account receivable holders of bankrupted companies for evaluation. 相似文献
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用改良的Kepes磷酸饥饿法诱导大肠杆菌K—12AM1264同步化生长,细胞经8轮同步化步骤后可在磷酸不限制培养基中自由生长保持2~3次同步化细胞周期。K—12AM1264大肠杆菌的细胞增倍和分化周期分别为55和15min,同步化细胞周期可分达3个时相。细胞分裂期(P),细胞分裂和染色体复制起始间期(Q)以及染色体复制起始和细胞分裂间期(R)。R期又可分R1和R2两个亚期。在R1亚期胸腺呼啶掺入DNA的速度增加,在R2亚期掺入速度保持恒定。R1和R2期分别为15和10min。 相似文献
6.
Glutamate receptors: RNA editing and death of motor neurons 总被引:1,自引:0,他引:1
The aetiology of sporadic amyotrophic lateral sclerosis (ALS), a fatal paralytic disease, is largely unknown. Here we show that there is a defect in the editing of the messenger RNA encoding the GluR2 subunit of glutamate AMPA receptors in the spinal motor neurons of individuals affected by ALS. This failure to swap an arginine for a glutamine residue at a crucial site in the subunit, which occurs normally in the affected brain areas of patients with other neurodegenerative diseases, will interfere with the correct functioning of the glutamate receptors and may be a contributory cause of neuronal death in ALS patients. 相似文献
7.
Sato T Mushiake S Kato Y Sato K Sato M Takeda N Ozono K Miki K Kubo Y Tsuji A Harada R Harada A 《Nature》2007,448(7151):366-369
A number of proteins are known to be involved in apical/basolateral transport of proteins in polarized epithelial cells. The small GTP-binding protein Rab8 was thought to regulate basolateral transport in polarized kidney epithelial cells through the AP1B-complex-mediated pathway. However, the role of Rab8 (Rab8A) in cell polarity in vivo remains unknown. Here we show that Rab8 is responsible for the localization of apical proteins in intestinal epithelial cells. We found that apical peptidases and transporters localized to lysosomes in the small intestine of Rab8-deficient mice. Their mislocalization and degradation in lysosomes led to a marked reduction in the absorption rate of nutrients in the small intestine, and ultimately to death. Ultrastructurally, a shortening of apical microvilli, an increased number of enlarged lysosomes, and microvillus inclusions in the enterocytes were also observed. One microvillus inclusion disease patient who shows an identical phenotype to Rab8-deficient mice expresses a reduced amount of RAB8 (RAB8A; NM_005370). Our results demonstrate that Rab8 is necessary for the proper localization of apical proteins and the absorption and digestion of various nutrients in the small intestine. 相似文献
8.
Evidence from fluid inclusions for microbial methanogenesis in the early Archaean era 总被引:5,自引:0,他引:5
Methanogenic microbes may be one of the most primitive organisms, although it is uncertain when methanogens first appeared on Earth. During the Archaean era (before 2.5 Gyr ago), methanogens may have been important in regulating climate, because they could have provided sufficient amounts of the greenhouse gas methane to mitigate a severely frozen condition that could have resulted from lower solar luminosity during these times. Nevertheless, no direct geological evidence has hitherto been available in support of the existence of methanogens in the Archaean period, although circumstantial evidence is available in the form of approximately 2.8-Gyr-old carbon-isotope-depleted kerogen. Here we report crushing extraction and carbon isotope analysis of methane-bearing fluid inclusions in approximately 3.5-Gyr-old hydrothermal precipitates from Pilbara craton, Australia. Our results indicate that the extracted fluids contain microbial methane with carbon isotopic compositions of less than -56 per thousand included within original precipitates. This provides the oldest evidence of methanogen (> 3.46 Gyr ago), pre-dating previous geochemical evidence by about 700 million years. 相似文献
9.
Nodal antagonists regulate formation of the anteroposterior axis of the mouse embryo 总被引:1,自引:0,他引:1
Yamamoto M Saijoh Y Perea-Gomez A Shawlot W Behringer RR Ang SL Hamada H Meno C 《Nature》2004,428(6981):387-392
Patterning of the mouse embryo along the anteroposterior axis during body plan development requires migration of the distal visceral endoderm (DVE) towards the future anterior side by a mechanism that has remained unknown. Here we show that Nodal signalling and the regionalization of its antagonists are required for normal migration of the DVE. Whereas Nodal signalling provides the driving force for DVE migration by stimulating the proliferation of visceral endoderm cells, the antagonists Lefty1 and Cerl determine the direction of migration by asymmetrically inhibiting Nodal activity on the future anterior side. 相似文献
10.
An empty spot refers to an empty hard-to-fill space which can be found in the records of the social interaction, and is the clue to the persons in the underlying social network who do not appear in the records. This contribution addresses a problem to predict relevant empty spots in social interaction. Homogeneous and inhomogeneous networks are studied as a model underlying the social interaction. A heuristic predictor function method is presented as a new method to address the problem. Simulation experiment is demonstrated over a homogeneous network. A test data set in the form of market baskets is generated from the simulated communication. Precision to predict the empty spots is calculated to demonstrate the performance of the presented method. 相似文献