47 research outputs found

    A Dog in the Cancer Fight: Comparative Oncology in Osteosarcoma

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    Since the great Rudolf Virchow advised, “Between animal and human medicine there is no dividing line, nor should there be,” limited attention has been paid to cancer in animals. This is finally changing thanks to a renewed focus on studying pet dogs with cancer. Unlike the laboratory mice who have been the mainstay of animal models of disease, pet dogs share an environment with their human owners, have an intact immune system, and often develop diseases spontaneously in ways that mimic their human counterparts. Osteosarcoma (OSA) – while uncommon in humans - is a common malignancy in dogs. This comparatively high incidence alone renders pet dogs an ideal “model” to conduct translational and clinical research into OSA. Indeed, there are many similarities between the two species with respect to this disease. However, owing to the shorter life span and accelerated disease progression, treatment effects can be assessed much more rapidly in canines than in humans. Overall, dogs represent a unique model to study OSA; this chapter aims to discuss the ways that comparative oncology between dogs and humans are being used from basic science research, to genetics and mechanisms of disease, to tumor biology and finally to developing novel treatments

    Predictions from Quantum Cosmology

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    The world view suggested by quantum cosmology is that inflating universes with all possible values of the fundamental constants are spontaneously created out of nothing. I explore the consequences of the assumption that we are a `typical' civilization living in this metauniverse. The conclusions include inflation with an extremely flat potential and low thermalization temperature, structure formation by topological defects, and an appreciable cosmological constant.Comment: (revised version), 15 page

    Superficial Soft-Tissue Sarcomas Rarely Require Advanced Soft-Tissue Reconstruction Following Resection

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    Objective: Soft-tissue sarcomas are most frequently located deep within myofascial compartments. Superficial soft-tissue sarcomas (S-STS) are relatively less common and may be managed differently than deep sarcomas because generous resection margins are often possible without sacrificing critical structures. We sought to investigate the frequency and types of soft-tissue reconstructive procedures that are required following excision of S-STS. Methods: We reviewed 457 consecutively treated patients with S-STS with a minimum 2-year follow-up from our prospectively maintained database between 1989 and 2009. Results: Mean follow-up was 10.5 years (range, 2–23). Four hundred twenty-one tumors (91%) were excised with negative margins, 38 (8.3%) had microscopically positive margins, and three (0.7%) had grossly positive margins. One patient required an amputation. In 271 (58%) patients, the wounds were closed primarily. In comparison, 93 patients (20%) required a rotation flap, 70 (15%) required a split-thickness skin graft, and 23 (5%) underwent a free tissue transfer (ie, advanced reconstructive procedure). The overall complication rate was 12%, although 43% of patients undergoing free tissue transfer developed complications (P = 0.04). An unplanned excision before referral to our center was a risk factor for local recurrence (P = 0.03) when residual tumor was recovered in the reexcision specimen pathologically. Conclusions: Although concern about the morbidity associated with a free tissue transfer (ie, advanced reconstructive procedure) may potentially limit the adequacy of resection in some patients with S-STS, the results of this study showed that the majority of patients had complete excisions with negative margins and primary closure. Obtaining a negative margin when excising a known or suspected S-STS rarely requires an advanced reconstructive procedure and almost never results in loss of limb

    Interaction between vortices in models with two order parameters

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    The interaction energy and force between widely separated strings is analyzed in a field theory having applications to superconducting cosmic strings, the SO(5) model of high-temperature superconductivity, and solitons in nonlinear optics. The field theory has two order parameters, one of which is broken in the vacuum (giving rise to strings), the other of which is unbroken in the vacuum but which could nonetheless be broken in the core of the string. If this does occur, there is an effect on the energetics of widely separated strings. This effect is important if the length scale of this second order parameter is longer than that of the other fields in the problem.Comment: 11 pages, 3 figures. Minor changes in the text. Accepted for publication in Phys. Rev.

    Cosmic Strings and the String Dilaton

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    The existence of a dilaton (or moduli) with gravitational-strength coupling to matter imposes stringent constraints on the allowed energy scale of cosmic strings, η\eta. In particular, superheavy gauge strings with η∼1016GeV\eta \sim 10^{16} GeV are ruled out unless the dilaton mass m_{\phi} \gsim 100 TeV, while the currently popular value mϕ∼1TeVm_{\phi} \sim 1 TeV imposes the bound \eta \lsim 3 \times 10^{11} GeV. Similar constraints are obtained for global topological defects. Some non-standard cosmological scenarios which can avoid these constraints are pointed out.Comment: 16 page

    Gravitational wave background from hybrid topological defects

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    We investigate the spectrum of stochastic gravitational wave background generated by hybrid topological defects: domain walls bounded by strings and monopoles connected by strings. Such defects typically decay early in the history of the universe, and their mass scale is not subject to the constraints imposed by microwave background and millisecond pulsar observations. Nonetheless, the intensity of the gravitational wave background from hybrid defects can be quite high at frequencies above 10−8Hz10^{-8} Hz, and in particular in the frequency range of LIGO, VIRGO and LISA detectors.Comment: 11 pages, uses ReVTeX, 2 postscript figures. Detection of a gravitational background by first generation detectors is only marginally possible, BUT detection by second generation detectors is almost certai

    Decay of Metastable Topological Defects

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    We systematically analyze the decay of metastable topological defects that arise from the spontaneous breakdown of gauge or global symmetries. Quantum-mechanical tunneling rates are estimated for a variety of decay processes. The decay rate for a global string, vortex, domain wall, or kink is typically suppressed compared to the decay rate for its gauged counterpart. We also discuss the decay of global texture, and of semilocal and electroweak strings.Comment: 43 pages, harvmac, HUTP-92/A018, CALT-68-178

    Search for Baryon and Lepton Number Violating Decays of the τ\tau Lepton

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    We have searched for five decay modes of the tau lepton that simultaneously violate lepton and baryon number: tau -> anti-proton gamma, tau -> anti-proton pi0, tau -> anti-proton eta, tau -> anti-proton 2pi0, and tau -> anti-proton pi0eta. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR). The integrated luminosity of the data sample is 4.7 fb^{-1}, corresponding to the production of 4.3 x 10^6 tau+tau- events. No evidence is found for any of the decays, resulting in much improved upper limits on the branching fractions for the two-body decays and first upper limits for the three-body decays.Comment: 8 pages, postscript file also available through http://w4.lns.cornell.edu/public/CLN

    Search for heavy lepton partners of neutrinos in proton-proton collisions in the context of the type III seesaw mechanism

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    This is the Pre-print version of the Article. The official publishe version can be accessed from the link below - Copyright @ 2012 ElsevierA search is presented in proton–proton collisions at sqrt(s) = 7TeV for fermionic triplet states expected in type III seesaw models. The search is performed using final states with three isolated charged leptons and an imbalance in transverse momentum. The data, collected with the CMS detector at the LHC, correspond to an integrated luminosity of 4.9 fb−1. No excess of events is observed above the background predicted by the standard model, and the results are interpreted in terms of limits on production cross sections and masses of the heavy partners of the neutrinos in type III seesaw models. Depending on the considered scenarios, lower limits are obtained on the mass of the heavy partner of the neutrino that range from 180 to 210 GeV. These are the first limits on the production of type III seesaw fermionic triplet states reported by an experiment at the LHC.This study is spported by the BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie programme and the European Research Council (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); and the HOMING PLUS programme of Foundation for Polish Science, cofinanced from European Union, Regional Development Fund
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