首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
《Endeavour》2020,44(1-2):100717
Mario Bunge, the centenarian Argentine/Canadian physicist/philosopher passed away in the loving company of his wife Marta and children Eric and Silvia on February 24, 2020 in Montréal, Ontario. This memoriam reviews his life and work, particularly his contributions to physics and philosophy of science.  相似文献   

4.
A review is presented of the present status of the theory, the developed technology and the current applications of dielectrophoresis (DEP). Over the past 10 years around 2000 publications have addressed these three aspects, and current trends suggest that the theory and technology have matured sufficiently for most effort to now be directed towards applying DEP to unmet needs in such areas as biosensors, cell therapeutics, drug discovery, medical diagnostics, microfluidics, nanoassembly, and particle filtration. The dipole approximation to describe the DEP force acting on a particle subjected to a nonuniform electric field has evolved to include multipole contributions, the perturbing effects arising from interactions with other cells and boundary surfaces, and the influence of electrical double-layer polarizations that must be considered for nanoparticles. Theoretical modelling of the electric field gradients generated by different electrode designs has also reached an advanced state. Advances in the technology include the development of sophisticated electrode designs, along with the introduction of new materials (e.g., silicone polymers, dry film resist) and methods for fabricating the electrodes and microfluidics of DEP devices (photo and electron beam lithography, laser ablation, thin film techniques, CMOS technology). Around three-quarters of the 300 or so scientific publications now being published each year on DEP are directed towards practical applications, and this is matched with an increasing number of patent applications. A summary of the US patents granted since January 2005 is given, along with an outline of the small number of perceived industrial applications (e.g., mineral separation, micropolishing, manipulation and dispensing of fluid droplets, manipulation and assembly of micro components). The technology has also advanced sufficiently for DEP to be used as a tool to manipulate nanoparticles (e.g., carbon nanotubes, nano wires, gold and metal oxide nanoparticles) for the fabrication of devices and sensors. Most efforts are now being directed towards biomedical applications, such as the spatial manipulation and selective separation∕enrichment of target cells or bacteria, high-throughput molecular screening, biosensors, immunoassays, and the artificial engineering of three-dimensional cell constructs. DEP is able to manipulate and sort cells without the need for biochemical labels or other bioengineered tags, and without contact to any surfaces. This opens up potentially important applications of DEP as a tool to address an unmet need in stem cell research and therapy.  相似文献   

5.
6.
7.
《Endeavour》1999,23(3):118-120
During the late nineteenth century, many countries in tropical Latin America organized research institutions for the study of natural history. The political and economic élites who sponsored these institutions hoped to find new natural resources that could be sold to Europe and North America's expanding markets. The coffee, sugar and banana industries in tropical Latin America were growing rapidly, and the northern markets were hungry for tropical products. The scientists who worked at the museums hoped to meet these national goals while at the same time participating in the international scientific community. Costa Rica, one of the smallest countries in the region, was also one of the most successful at organizing a productive and vibrant natural history research community.  相似文献   

8.
9.
This paper examines how the relationship between firm value and patent-based indicators of inventive activity has changed over time. We use data from more than 33,000 mergers and acquisitions deals between 1985 and 2007, and distinguish between American (USPTO) and European (EPO) patents. Our results indicate that over time EPO patents have become the dominant indicator of innovative activity, while USPTO patents have no effect on firm value near the end of the sample period. The results are robust to controlling for citations and are especially strong for small firms, for firms operating in the drug and chemical industries, and when target and acquiring firms operate in different industries or countries.  相似文献   

10.
11.
12.
In this essay, I argue that popular entertainment can be understood in terms of Husserl’s concepts of epochē, reduction and constitution, and, conversely, that epochē, reduction and constitution can be explicated in terms of popular entertainment. To this end I use Husserl’s concepts to explicate and reflect upon the psychological and ethical effects of an exemplary instance of entertainment, the renowned Star Trek episode entitled “The Measure of a Man.” The importance of such an exercise is twofold: (1) to demonstrate, once again, the fecundity of the methodological procedures Husserl bequeathed to us; more than any other philosopher, he tapped into the fundamental manners in which we lose, make and remake the meanings of our lives; and (2) to demonstrate how popular entertainment, similarly, plays a central role in the making and remaking of the meanings of our lives. If my zig-zag procedure between Husserl’s philosophy and popular entertainment is productive and cogent, in addition to elucidating Husserl’s philosophy, it will demonstrate the reality-generating potency and the constitutive power of entertainment in the contemporary world. Entertainment, via ourselves, has become the primary producer of the meanings via which consciousness constitutes the world.  相似文献   

13.
14.
The Academy of Opto-Electronics (AOE) is an institution under the direct jurisdiction of the CAS headquarters. Organizationally, it has six components: the head office, the Changchun Institute of Optics, Fine Mechanics & Physics (CIOMP), the Shanghai Institute of Technical Physics (SITP), the Xi’an Institute of Optics & Precision Mechanics (XIOM), the Shanghai Institute of Optics & Fine Me- chanics (SIOM) and the Institute of Optics & Electron- ics (IOE) in Chengdu. The p…  相似文献   

15.
16.
17.
18.

Economics-related ICT research has moved from the fringes of the discipline to penetrate all of its branches. It is, therefore, not a separate economics subdiscipline. It is also unlikely to become part of an “ICT or Internet research” proto-discipline. Instead, it should be seen as only one part of a bigger agenda toward a proper “information and knowledge economics” and possibly a future proto-discipline of a “unified theory of information and knowledge” or a meta-discipline of information sciences.  相似文献   

19.
The work reported in Ref. (1), carried out on n-heptane from 273·16K to the critical point (under moderate pressures), is extended to five n-alkanes, benzene, mercury and water under saturation pressures and extended to much lower temperatures.Forty calculations of various thermodynamic quantities pertaining to the liquids here studied (648 points) are presented in Tables II-IV. All parameters and physical constants involved are presented in Table V. The Standard Percentage Errors (SPE) for all the calculations and the temperature ranges are given in Table VI. The grand average SPE for the 648 points is about one-third of 1%. Only one calculation (the temperature of water from 393·16 to 563·16 K) had an error greater than 1% (18 points).  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号