2,497 research outputs found
Electronic transport through a quantum dot network
The conductance through a finite quantum dot network is studied as a function
of inter-dot coupling. As the coupling is reduced, the system undergoes a
transition from the antidot regime to the tight binding limit, where Coulomb
resonances with on average increasing charging energies are observed.
Percolation models are used to describe the conduction in the open and closed
regime and contributions from different blockaded regions can be identified. A
strong negative average magnetoresistance in the Coulomb blockade regime is in
good quantitative agreement with theoretical predictions for magnetotunneling
between individual quantum dots.Comment: 5 pages, 5 figure
Apparatus for growing crystals
An improved apparatus and method for growing crystals from a melt employing a heat pipe, consisting of one or more sections, each section serving to control temperature and thermal gradients in the crystal as it forms inside the pipe
Unproceedings of the Fourth .Astronomy Conference (.Astronomy 4), Heidelberg, Germany, July 9-11 2012
The goal of the .Astronomy conference series is to bring together
astronomers, educators, developers and others interested in using the Internet
as a medium for astronomy. Attendance at the event is limited to approximately
50 participants, and days are split into mornings of scheduled talks, followed
by 'unconference' afternoons, where sessions are defined by participants during
the course of the event. Participants in unconference sessions are discouraged
from formal presentations, with discussion, workshop-style formats or informal
practical tutorials encouraged. The conference also designates one day as a
'hack day', in which attendees collaborate in groups on day-long projects for
presentation the following morning. These hacks are often a way of
concentrating effort, learning new skills, and exploring ideas in a practical
fashion. The emphasis on informal, focused interaction makes recording
proceedings more difficult than for a normal meeting. While the first
.Astronomy conference is preserved formally in a book, more recent iterations
are not documented. We therefore, in the spirit of .Astronomy, report
'unproceedings' from .Astronomy 4, which was held in Heidelberg in July 2012.Comment: 11 pages, 1 figure, .Astronomy 4, #dotastr
Effects of naturopathic medicines on Multiplate and ROTEM: a prospective experimental pilot study in healthy volunteers
Of patients undergoing surgery, 22 to 57 % have been reported to be using naturopathic medicines. Several of these medicines have been reported to increase bleeding or enhance the effect of other drugs that increase bleeding. The Swedish Medical Products Agency recommends cessation of the use of the naturopathic medicines echinacea, fish oil, ginkgo biloba, ginseng, St. John's wort, valeriana and garlic 2 weeks before surgery. The aim of this pilot study was to examine the effects of these 7 naturopathic medicines in healthy humans by utilising multiple electrode aggregometer (Multiplate) and viscoelastic rotational thromboelastometer (ROTEM) to obtain data for sample size calculation before a larger trial
Study of some factors affecting efficiency of reproduction in dairy cattle serviced by artificial insemination
This bulletin is a report on Department of Dairy Husbandry research project number 89 entitled 'Increasing the effectiveness of artificial insemination as a means of improving dairy cattle'--P. [2].Includes bibliographical references (pages 40-42)
West Nile premembrane-envelope genetic vaccine encoded as a chimera containing the transmembrane and cytoplasmic domains of a lysosome-associated membrane protein: increased cellular concentration of the transgene product, targeting to the MHC II compartment, and enhanced neutralizing antibody response
AbstractA genetic vaccine for West Nile virus (WN) has been synthesized with the WN premembrane-envelope (WN preM-E) gene sequences encoded as a chimera with the transmembrane and carboxyl terminal domains of the lysosome-associated membrane protein (LAMP). The LAMP sequences are used to direct the antigen protein to the major histocompatibility class II (MHC II) vesicular compartment of transfected professional antigen-presenting cells (APCs). Vaccine constructs encoding the native WN preM-E and WN preM-E/LAMP chimera were synthesized in pVAX1 and pITR plasmid backbones. Extracts of human fibroblast 293 and monkey kidney COS-7 cells transfected with the WN preM-E/LAMP chimera constructs contained much greater amounts of E than did the cells transfected with constructs encoding the native WN preM-E. This difference in the concentration of native E and the E/LAMP chimera in transfected cells is attributed to the secretion of native E. The amount of preM protein in cell extracts, in contrast to the E protein, and the levels of DNA and RNA transcripts, did not differ between WN preM-E- and WN preM-E/LAMP-transfected cells. Additionally, confocal and immunoelectron microscopic analyses of transfected B cells showed localization of the WN preM-E/LAMP chimera in vesicular compartments containing endogenous LAMP, MHC II, and H2-M, whereas native viral preM-E lacking the LAMP sequences was distributed within the cellular vesicular network with little LAMP or MHC II association. Mice immunized with a DNA construct expressing the WN preM-E/LAMP antigen induced significant antibody and long-term neutralization titers in contrast to the minimal and short-lived neutralization titer of mice vaccinated with a plasmid expressing the untargeted antigen. These results underscore the utility of LAMP targeting of the WN envelope to the MHC II compartments in the design of a genetic WN vaccine
Sympatric woodland Myotis bats form tight-knit social groups with exclusive roost home ranges (dataset)
The article relating to this dataset is available in ORE: http://hdl.handle.net/10871/15799Dataset associated with the PLOS journal article with the same title. The two sets of data in the Excel file were used to create the networks in the Tiff file.Natural Environment Research Council (NERC
Identifying Primordial Substructure in NGC 2264
We present new Spitzer Space Telescope observations of the young cluster
NGC2264. Observations at 24 micron with the Multiband Imaging Photometer has
enabled us to identify the most highly embedded and youngest objects in
NGC2264. This letter reports on one particular region of NGC2264 where bright
24 micron sources are spatially configured in curious linear structures with
quasi-uniform separations. The majority of these sources (~60% are found to be
protostellar in nature with Class I spectral energy distributions. Comparison
of their spatial distribution with sub-millimeter data from Wolf-Chase (2003)
and millimeter data from Peretto et al. (2005) shows a close correlation
between the dust filaments and the linear spatial configurations of the
protostars, indicating that star formation is occurring primarily within dense
dusty filaments. Finally, the quasi-uniform separations of the protostars are
found to be comparable in magnitude to the expected Jeans length suggesting
thermal fragmentation of the dense filamentary material.Comment: Accepted for publication in ApJL, 5 pages, 4 figures. Color version
available from the following webpages: http://cfa-www.harvard.edu/~pteixeir/
and http://cfa-www.harvard.edu/~clada
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