146,656 research outputs found
Local Electrical Stress-Induced Doping and Formation of 2D Monolayer Graphene P-N Junction
We demonstrated doping in 2D monolayer graphene via local electrical
stressing. The doping, confirmed by the resistance-voltage transfer
characteristics of the graphene system, is observed to continuously tunable
from N-type to P-type as the electrical stressing level (voltage) increases.
Two major physical mechanisms are proposed to interpret the observed phenomena:
modifications of surface chemistry for N-type doping (at low-level stressing)
and thermally-activated charge transfer from graphene to SiO2 substrate for
P-type doping (at high-level stressing). The formation of P-N junction on 2D
graphene monolayer is demonstrated with complementary doping based on locally
applied electrical stressing.Comment: 12 pages, 4 figure
ETEC colonisation factors disrupt the antigen presenting capacity of porcine intestinal dendritic cells
Enterotoxigenic E. coli (ETEC) are not only a major cause of diarrhoea in travellers to and children in developing countries, but also cause neonatal and postweaning diarrhoea in piglets, leading to a reduced feed conversion and a higher mortality rate. As a consequence ETEC infections result in severe economic losses in the swine production industry. This intestinal pathogen displays colonisation factors or fimbriae on its surface enabling the microorganism to adhere to the intestinal epithelium (Fig. 1). In pig, F4 and F18 fimbriae are the most frequently associated with ETEC-induced diarrhoea1. As opposed to F4 fimbriae, oral immunisation with F18 fimbriae doesn’t protect piglets from a subsequent challenge infection2. F18 fimbriae bind glycosphingolipids in the apical membrane of enterocytes, but no transcytosis occurs, resulting in lower sunepithelial antigen concentrations as compared to F4 fimbriae, which bind the transcytotic receptor aminopeptidase N3,4. However, M-cell mediated transport of F18 fimbriae should still occur. Hence, besides a lower antigen concentration, these fimbriae could affect the function of intestinal antigen presenting cells. Here, we investigated the influence of purified F18 fimbriae on the antigen presentation capacity of small intestinal lamina propria dendritic cells (LPDCs)
How Design Plays Strategic Roles in Internet Service Innovation: Lessons from Korean Companies
In order to survive in the highly competitive internet business, companies have to provide differentiated services that can satisfy the rapidly changing users’ tastes and needs. Designers have been increasingly committed to achieving user satisfaction by generating and visualizing innovative solutions in new internet service development. The roles of internet service design have expanded from a narrow focus on aesthetics into a more strategic aspect. This paper investigates the methods of managing design in order to enhance companies’ competitiveness in internet business. The main research processes are to: (1) explore the current state of internet service design in Korea through in-depth interviews with professional designers and survey questionnaires to 30 digital design agencies and 60 clients; (2) compare how design is managed between in-house design groups and digital design agencies though the case studies of five Korean companies; and (3) develop a taxonomy characterizing four roles of designers in conjunction with the levels of their strategic contributions to internet service innovation: visualist, solution provider, concept generator, and service initiator. In addition, we demonstrate the growing contributions of the strategic use of design for innovating internet services, building robust brand equity, and increasing business performance.
Keywords:
Design Management; Internet Business; Internet Service Design; Digital Design; Digital Design Agency; In-House Design Group, Case Study</p
Charge-mass ratio bound and optimization in the Parikh-Wilczek tunneling model of Hawking radiation
In this letter, we study the mutual information hidden in the Parikh-Wilczek
tunneling model of Hawking radiation for Reissner-Norstrom black holes. We
argue that the condition of nonnegativity of mutual information suggests
bound(s) for charge-mass ratio of emitted particles. We further view the
radiation as an optimization process and discuss its effect on time evolution
of a charged black hole.Comment: 4 pages, 5 figures, submitted version to PL
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