389 research outputs found
Gyrotropic impact upon negatively refracting surfaces
Surface wave propagation at the interface between different types of gyrotropic materials and an isotropic negatively refracting medium, in which the relative permittivity and relative permeability are, simultaneously, negative is investigated. A general approach is taken that embraces both gyroelectric and gyromagnetic materials, permitting the possibility of operating in either the low GHz, THz or the optical frequency regimes. The classical transverse Voigt configuration is adopted and a complete analysis of non-reciprocal surface wave dispersion is presented. The impact of the surface polariton modes upon the reflection of both plane waves and beams is discussed in terms of resonances and an example of the influence upon the Goos–Hänchen shift is given
Higgs-Boson Decay to Four Fermions Including a Single Top Quark Below Threshold
The rare decay modes Higgs four light fermions, and Higgs
single top-quark + three light fermions for , are
presented, and phenomenologically interpreted. The angular correlation between
fermion planes is presented as a test of the spin and intrinsic parity of the
Higgs particle. In Higgs decay to single top, two tree-level graphs contribute
in the standard model (SM); one couples the Higgs to , and
one to t\bar t(\sim g_{top\;yukawa}=m_t/246\GeV). The large Yukawa coupling
for m_t>100\GeV makes the second amplitude competitive or dominant for most
values. Thus the Higgs decay rate to single top directly probes the
SM universal mechanism generating both gauge boson and fermion masses, and
offers a means to infer the Higgs- Yukawa coupling when is kinematically disallowed. We find that the modes at the SSC, and at future high energy,
high luminosity colliders, may be measureable if is not too far above
. We classify non-standard Higgses as gaugeo-phobic, fermio-phobic or
fermio-philic, and discuss the Higgs single top rates for these
classes.Comment: 30 pages, 6 figures (figures available upon request); VAND-TH-93/
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Some Aspects of the Prospective Experimental Use of the Stanford Two-Mile Accelerator
Eleven papers dealing with photon beams from the accelerator, use of hydrogen bubble chambers and spark chambers, a storage ring for 10-Bev muons, muon beams and -p scattering experiments, mass analysis of highenergy accelerator beams, the search for intermediate bosons and heavy leptons, particle yields arising from decay of short-lived intermediate particles, and conjectures on the effects of Regge poles on Drell processes are included. Separate abstracts were prepared for the eleven papers. (D.C.W.
The assessment of information technology maturity in emergency response organizations
[EN] In emergency response organizations, information technologies are not
adequately explored. Sometimes, the mere adoption of new information technologies
is not productive, as their efficient use depends on other interrelated technologies and
the environment where they are installed. This work describes a model to help organizations
understand their capability in respect to the adoption of these technologies.
The model also helps the performing of the evaluation from different perspectives,
making it suitable to collaborative evaluation. Using the proposed model, an organization
can measure its maturity level in different aspects of the evaluation and guide
the investment on its capabilities. Part of the model has been developed for emergency
response organizations and the information technology dimension of the model has
been applied to two fire department installations.Marcos R. S. Borges was partially supported by grants No. 560223/2010-2 and 480461/2009-0 from CNPq (Brazil). Work of José H. Canós is partially funded by the Spanish Ministerio. de Educación y Ciencia (MEC) under grant TIPEX (TIN2010–19859-C03-03). The cooperation between
the Brazilian and the Spanish research groups was partially sponsored by the CAPES/MECD Cooperation Program, Project #169/ PHB2007-0064-PC.Santos, RS.; Borges, MRS.; Canos Cerda, JH.; Gomes, JO. (2011). The assessment of information technology maturity in emergency response organizations. Group Decision and Negotiation. 20(5):593-613. doi:10.1007/s10726-011-9232-zS593613205Bigley G, Roberts KH (2001) The incident command system: high reliability organizing for complex and volatile task environments. Acad Manag J 44(6): 1281–1299Chinowsky P, Molenaar K, Realph A (2007) Learning organizations in construction. J Manag Eng 23(1): 27–34Diniz VB, Borges MRS, Gomes JO, Canós JH (2008) Decision making support in emergency response. In: Encyclopedia of decision making, Information Science Reference (an imprint of IGI Global), New York, pp 184–191Dörner R, Grimm P, Seiler C (2001) ETOILE—an environment for team, organizational and individual learning. CG Top 13(3): 5–6Dykstra E (2003) Concept paper: toward an international system model in emergency management. In: Proceedings of toward an international system model in emergency management, Public Entity Risk InstituteFederal Emergency Management Agency (FEMA) (1998) Emergency management guide for business and industry: a step-by-step approach to emergency planning, response and recovery for companies of all sizesGu Q, Mendonça D (2005) Patterns of group information seeking in a simulated emergency response environment. In: Proceedings of the 2nd international ISCRAM conference, Brussels, BelgiumHale J (1997) A layered communication architecture for the support of crisis response. J Manag Inf Syst 14(1): 235–255King W, Teo T (1997) Integration between business planning and information systems planning: validating a stage hypothesis. Decis Sci 28(2): 279–307Lachner J, Hellwagner H (2008) Information and communication systems for mobile emergency response. Lecture notes in business information processing, vol 5. pp 213–224Lavoie D, Culbert A (1978) Stages in organization and development. Human Relat 31(5): 417–438Lindel MK, Prater C, Perry RW (2007) Emergency management. Wiley, New YorkLlavador M, Letelier P, Penadés MC, Borges MRS, Solís C (2006) Precise yet flexible specification of emergency resolution procedures. In: Proceedings of the information systems for crisis response and management (ISCRAM), pp 110–120Meissner A, Wang Z, Putz W, Grimmer J (2006) MIKoBOS: a mobile information and communication system for emergency response. In: Proceedings of the 3rd international ISCRAM conference, Newark, New JerseyNonaka I, Takeuchi H (1995) The knowledge creating company: how Japanese companies create the dynamics of innovation. Oxford University Press, OxfordOchoa S, Neyem A, Pino JA, Borges MRS (2007) Supporting group decision making and coordination in urban disasters relief efforts. J Decis Syst 16(2): 143–172Paton D, Flin R (1999) Disaster stress: an emergency management perspective. Disaster Prev Manag 8(4): 261–267Paulk MC, Weber C, Curtis B, Chrissis M (1995) The capability maturity model: guidelines for improving the software process. Addison-Wesley, ReadingQuarantelli EL (1997) Problematical aspects of the information/communication revolution for disaster planning and research: ten non-technical issues and questions. Disaster Prev Manag 6(2): 94–106Santos RS, Borges MRS, Gomes JO, Canós JH (2008) Maturity levels of information technologies in emergency response organizations. In: Proceedings of the international workshop on groupware, Omaha, Nebraska, USA. Groupware: design, implementation and use. Lecture notes in computer science, vol 5411. Springer, Berlin, pp 135–150Schoenharl T, Szabo G, Madey G, Barabasi AL (2006) WIPER: a multi-agent system for emergency response. In: Proceedings of the 3rd international ISCRAM conference, Newark, New JerseyTuroff M (2002) Past and future emergency response information systems. Commun ACM 45(4): 29–33Turoff M, Chumer M, Hiltz R, Clasher R, Alles M, Vasarhelyi M, Kogan A (2004a) Assuring homeland security: continuous monitoring, control and assurance of emergency preparedness. J Inf Technol Theor Appl (JITTA) 6(3): 1–24Turoff M, Chumer M, Vande Walle B, Yao X (2004b) The design of a dynamic emergency response management information system (DERMIS). J Inf Technol Theor Appl (JITTA) 5(4): 1–35Van der Lee MDE, Van Vugt M (2004) IMI—An information system for effective multidisciplinary incident management. In: Proceedings of the 1st international ISCRAM conference, Brussels, BelgiumYuan Y, Deltor B (2005) Intelligent mobile crisis response systems. Commun ACM 28(2): 95–98Zimmerman R, Restrepo CE (2006) Information technology (IT) and critical infrastructure interdependencies for emergency response. In: Proceedings of the 3rd international ISCRAM conference, Newark, New Jerse
The pp -> K^+Sigma^+n cross section from missing mass spectra
We utilize existing inclusive data on K^+ meson momentum spectra of the
reaction pp -> K^+X at T_p = 2.3 - 2.85 GeV to deduce total cross sections for
pp -> K^+\Sigma^+n. The method used to extract those cross sections is
explained and discussed in detail. Our result for T_p = 2.85 GeV is consistent
with the data point from a direct measurement at the same beam energy. The
cross section obtained for T_p = 2.3 GeV is with 13.7\pm2.3 \mu b considerably
smaller than the value found in a recent experiment by the COSY-11
Collaboration at a somewhat lower beam energy, indicating that the pp ->
K^+\Sigma^+n reaction cross section could exhibit a rather unusual energy
dependence.Comment: 12 pages, 8 figure
The AMANDA Neutrino Telescope
With an effective telescope area of order m for TeV neutrinos, a
threshold near 50 GeV and a pointing accuracy of 2.5 degrees per muon
track, the AMANDA detector represents the first of a new generation of high
energy neutrino telescopes, reaching a scale envisaged over 25 years ago. We
describe early results on the calibration of natural deep ice as a particle
detector as well as on AMANDA's performance as a neutrino telescope.Comment: 12 pages, Latex2.09, uses espcrc2.sty and epsf.sty, 13 postscript
files included. Talk presented at the 18th International Conference on
Neutrino Physics and Astrophysics (Neutrino 98), Takayama, Japan, June 199
Sensitivity of the IceCube Detector to Astrophysical Sources of High Energy Muon Neutrinos
We present the results of a Monte-Carlo study of the sensitivity of the
planned IceCube detector to predicted fluxes of muon neutrinos at TeV to PeV
energies. A complete simulation of the detector and data analysis is used to
study the detector's capability to search for muon neutrinos from sources such
as active galaxies and gamma-ray bursts. We study the effective area and the
angular resolution of the detector as a function of muon energy and angle of
incidence. We present detailed calculations of the sensitivity of the detector
to both diffuse and pointlike neutrino emissions, including an assessment of
the sensitivity to neutrinos detected in coincidence with gamma-ray burst
observations. After three years of datataking, IceCube will have been able to
detect a point source flux of E^2*dN/dE = 7*10^-9 cm^-2s^-1GeV at a 5-sigma
significance, or, in the absence of a signal, place a 90% c.l. limit at a level
E^2*dN/dE = 2*10^-9 cm^-2s^-1GeV. A diffuse E-2 flux would be detectable at a
minimum strength of E^2*dN/dE = 1*10^-8 cm^-2s^-1sr^-1GeV. A gamma-ray burst
model following the formulation of Waxman and Bahcall would result in a 5-sigma
effect after the observation of 200 bursts in coincidence with satellite
observations of the gamma-rays.Comment: 33 pages, 13 figures, 6 table
AAV-mediated rescue of Eps8 expression in vivo restores hair-cell function in a mouse model of recessive deafness
The transduction of acoustic information by hair cells depends upon mechanosensitive stereociliary bundles that project from their apical surface. Mutations or absence of the stereociliary protein EPS8 cause deafness in humans and mice, respectively. Eps8 knockout mice (Eps8−/−) have hair cells with immature stereocilia and fail to become sensory receptors. Here, we show that exogenous delivery of Eps8 using Anc80L65 in P1–P2 Eps8−/− mice in vivo rescued the hair bundle structure of apical-coil hair cells. Rescued hair bundles correctly localize EPS8, WHIRLIN, MYO15, and BAIAP2L2, and generate normal mechanoelectrical transducer currents. Inner hair cells with normal-looking stereocilia re-expressed adult-like basolateral ion channels (BK and KCNQ4) and have normal exocytosis. The number of hair cells undergoing full recovery was not sufficient to rescue hearing in Eps8−/− mice. Adeno-associated virus (AAV)-transduction of P3 apical-coil and P1–P2 basal-coil hair cells does not rescue hair cells, nor does Anc80L65-Eps8 delivery in adult Eps8−/− mice. We propose that AAV-induced gene-base therapy is an efficient strategy to recover the complex hair-cell defects in Eps8−/− mice. However, this therapeutic approach may need to be performed in utero since, at postnatal ages, Eps8−/− hair cells appear to have matured or accumulated damage beyond the point of repair
Analysis of data on low energy piN-->pipiN reaction. I. Total cross sections
This is the first of a series of papers on a consistent model independent
analysis of the complete experimental information on the reaction at pion momenta up to 500 MeV/c. The paper summarizes
the theoretical approach and details of the computational procedure. The
complete database on total cross sections in 5 channels is given
together with a critical discussion of their model independent analysis.Comment: 45 page
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