7,221 research outputs found
Modular AC coupled hybrid power systems for the emerging GHG mitigation products market
Bioenergy systems particularly waste to energy (WTE) systems are increasingly gaining prominence. Market for modular hybrid energy systems (HES) combining renewable energy sources including WTEs is potentially large. Novel configuration of AC coupling for HES is discussed. Emerging opportunities for market development of hybrid energy systems under green house gas mitigation initiatives particularly Kyoto flexibility mechanisms is analysed
Pioneers, Submariners, or Thicket-builders: Which Firms Use Continuations in Patenting?
The continuations procedure within the U.S. patent system has been criticized for enabling firms to manipulate the patent review process for strategic purposes. Changes during the 1990s in patent procedures affected the incentives of applicants to exploit the continuations process, and additional reforms in continuations currently are being considered. Nonetheless, little is known about applicants' use of the three major types of continuations -- the Continuation Application (CAP), the Continuations-In-Part (CIP), and Divisions -- to alter the term and scope of patents. This paper analyzes patents issued from the three types of continuations to U.S. firms during 1981 - 2004 (with priority years 1981 - 2000), and links their frequency to the characteristics of patents, assignees and industries. We find that CIPs are disproportionately filed by R&D-intensive, small firms that patent heavily, and are more common in chemical and biological technologies. Patents resulting from CIP filings contain more claims and backward citations per patent on average, and cover relatively "valuable" inventions. In contrast, CAPs cover less valuable patents from large, capital-intensive firms that patent intensively, particularly in computer and semiconductor patents. We also analyze the effects of the 1995 change in patent term on continuation applications and find that the Act reduced the use of continuations overall, while shifting the output of CAPs toward "less important" patents.
Stabilizing the electroweak vacuum by higher dimensional operators in a Higgs-Yukawa model
The Higgs boson discovery at the LHC with a mass of approximately 126 GeV
suggests, that the electroweak vacuum of the standard model may be metastable
at very high energies. However, any new physics beyond the standard model can
change this picture. We want to address this important question within a
lattice Higgs-Yukawa model as the limit of the standard model (SM). In this
framework we will probe the effect of a higher dimensional operator for which
we take a -term. Such a term could easily originate as
a remnant of physics beyond the SM at very large scales.
As a first step we investigate the phase diagram of the model including such
a operator. Exploratory results suggest the existence
of regions in parameter space where first order transitions turn to second
order ones, indicating the existence of a tri-critical line. We will explore
the phase structure and the consequences for the stability of the SM, both
analytically by investigating the constraint effective potential in lattice
perturbation theory, and by studying the system non-perturbatively using
lattice simulations.Comment: 7 pages, 6 figures; Proceedings of the 31st International Symposium
on Lattice Field Theory - LATTICE 201
Hydrothermal Ethanol Flames in Co-Flow Jets
Results on the autoignition and stabilization of ethanol hydrothermal flames in a Supercritical Water Oxidation (SCWO) reactor operating at constant pressure are reported. The flames are observed as luminous reaction zones occurring in supercritical water; i.e., water at conditions above its critical point (approximately 22 MPa and 374 C). A co-flow injector is used to inject fuel (inner flow), comprising an aqueous solution ranging from 20%-v to 50%-v ethanol, and air (annular flow) into a reactor filled with supercritical water at approximately 24.3 MPa and 425 C. Results show hydrothermal flames are autoignited and form diffusion flames which exhibit laminar and/or turbulent features depending upon flow conditions. Two orthogonal camera views are used; one providing a backlit shadowgraphic image of the co-flow jet and the other providing color images of the flame. In addition, spectroscopic measurements of flame emissions in the UV and visible spectrum are discussed
Endogenous human cytomegalovirus gB is efficiently presented by MHC class II molecules to CD4+ CTL
Human cytomegalovirus (HCMV) infects endothelial, epithelial, and glial cells in vivo. These cells can express MHC class II proteins, but are unlikely to play important roles in priming host immunity. Instead, it seems that class II presentation of endogenous HCMV antigens in these cells allows recognition of virus infection. We characterized class II presentation of HCMV glycoprotein B (gB), a membrane protein that accumulates extensively in endosomes during virus assembly. Human CD4+ T cells specific for gB were both highly abundant in blood and cytolytic in vivo. gB-specific CD4+ T cell clones recognized gB that was expressed in glial, endothelial, and epithelial cells, but not exogenous gB that was fed to these cells. Glial cells efficiently presented extremely low levels of endogenous gB--expressed by adenovirus vectors or after HCMV infection--and stimulated CD4+ T cells better than DCs that were incubated with exogenous gB. Presentation of endogenous gB required sorting of gB to endosomal compartments and processing by acidic proteases. Although presentation of cellular proteins that traffic into endosomes is well known, our observations demonstrate for the first time that a viral protein sorted to endosomes is presented exceptionally well, and can promote CD4+ T cell recognition and killing of biologically important host cells
Aerosol Characteristics at a high-altitude station Nainital during the ISRO-GBP Land Campaign-II
During the second land campaign (LC-II) organised by ISRO-GBP, extensive
ground-based measurements of aerosol characteristics were carried out over
Manora Peak (29.4oN; 79.5oE; 1951 metres above mean sea level), Nainital (a
high altitude station located in the Shivalik ranges of Central Himalayas)
during the dry, winter season (December) of 2004. These measurements included
the spectral aerosol optical depths (AOD), columnar water vapour content (W),
Total Columnar Ozone (TCO), total number concentration (NT) of near surface
aerosols, mass concentration of black carbon (MB), aerosol mass loading (MT),
and Global Solar Radiation. Based on these measured parameters, we present the
results on the near-surface and columnar properties of atmospheric aerosols at
Nainital.Comment: Published in the Proceedings of the ISRO-GBP Land-Campaign-II
meeting, Physical Research Laboratory, Ahmadabad (Inida), March 200
Night sky at the Indian Astronomical Observatory during 2000-2008
We present an analysis of the optical night sky brightness and extinction
coefficient measurements in UBVRI at the Indian Astronomical Observatory (IAO),
Hanle, during the period 2003-2008. They are obtained from an analysis of CCD
images acquired at the 2 m Himalayan Chandra Telescope at IAO. Night sky
brightness was estimated using 210 HFOSC images obtained on 47 nights and
covering the declining phase of solar activity cycle-23. The zenith corrected
values of the moonless night sky brightness in mag/square arcsecs are 22.14(U),
22.42(B), 21.28(V), 20.54(R) and 18.86(I) band. This shows that IAO is a dark
site for optical observations. No clear dependency of sky brightness with solar
activity is found. Extinction values at IAO are derived from an analysis of
1325 images over 58 nights. They are found to be 0.36 in U-band, 0.21 in
B-band, 0.12 in V-band, 0.09 in R-band and 0.05 in I-band. On average,
extinction during the summer months is slightly larger than that during the
winter months. No clear evidence for a correlation between extinction in all
bands and the average night time wind speed is found. Also presented here is
the low resolution moonless optical night sky spectrum for IAO covering the
wavelength range 3000-9300 \AA. Hanle region thus has the required
characteristics of a good astronomical site in terms of night sky brightness
and extinction, and could be a natural candidate site for any future large
aperture Indian optical-infrared telescope(s).Comment: 18 pages, 7 figures, uses basi.cls, accepted for publication in
Bulletin of the Astronomical Society of Indi
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