105 research outputs found
Spacetime and vacuum as seen from Moscow
An extended text of the talk given at the conference ``2001: A Spacetime
Odyssey'', to be published in the Proceedings of the Inaugural Conference of
the Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor,
21-25 May 2001, M.J. Duff and J.T. Liu eds., World Scientific, Singapore, 2002;
and of Historical Lecture ``Vacuum as seen from Moscow'' at the CERN Summer
School, 10 August, 2001. Contents: Introduction; Pomeranchuk on vacuum; Landau
on parity, P, and combined parity, CP; Search and discovery of ; "Mirror world"; Zeldovich and cosmological term; QCD vacuum
condensates; Sakharov and baryonic asymmetry of the universe, BAU; Kirzhnits
and phase transitions; Vacuum domain walls; Monopoles, strings, instantons, and
sphalerons; False vacuum; Inflation; Brane and Bulk; Acknowledgments;
References.Comment: 17 pages, 2 figure
A Search for leptophilic Z_(l) boson at future linear colliders
We study the possible dynamics associated with leptonic charge in future
linear colliders. Leptophilic massive vector boson, Z_(l), have been
investigated through the process e^(+)e^(-) -> mu^(+)mu^(-). We have shown that
ILC and CLIC will give opportunity to observe Z_(l) with masses up to the
center of mass energy if the corresponding coupling constant g_(l) exceeds
10^(-3).Comment: 12 pages, 10 figure
Pure-glue hidden valleys through the Higgs portal
We consider the possibility that the Higgs boson can act as a link to a
hidden sector in the context of pure-glue hidden valley models. In these models
the standard model is weakly coupled, through loops of heavy messengers fields,
to a hidden sector whose low energy dynamics is described by a pure-Yang-Mills
theory. Such a hidden sector contains several metastable hidden glueballs. In
this work we shall extend earlier results on hidden valleys to include
couplings of the messengers to the standard model Higgs sector. The effective
interactions at one-loop couple the hidden gluons to the standard model
particles through the Higgs sector. These couplings in turn induce hidden
glueball decays to fermion pairs, or cascade decays with multiple Higgs
emission. The presence of effective operators of different mass dimensions,
often competing with each other, together with a great diversity of states,
leads to a great variability in the lifetimes and decay modes of the hidden
glueballs. We find that most of the operators considered in this paper are not
heavily constrained by precision electroweak physics, therefore leaving plenty
of room in the parameter space to be explored by the future experiments at the
LHC.Comment: 44 pages, 16 figures. Major revision for JHEP, corrected an error in
Eq. 5.1, comments adde
Expression of Toll-Like Receptors in the Developing Brain
Toll-like receptors (TLR) are key players of the innate and adaptive immune response in vertebrates. The original protein Toll in Drosophila melanogaster regulates both host defense and morphogenesis during development. Making use of real-time PCR, in situ hybridization, and immunohistochemistry we systematically examined the expression of TLR1–9 and the intracellular adaptor molecules MyD88 and TRIF during development of the mouse brain. Expression of TLR7 and TLR9 in the brain was strongly regulated during different embryonic, postnatal, and adult stages. In contrast, expression of TLR1–6, TLR8, MyD88, and TRIF mRNA displayed no significant changes in the different phases of brain development. Neurons of various brain regions including the neocortex and the hippocampus were identified as the main cell type expressing both TLR7 and TLR9 in the developing brain. Taken together, our data reveal specific expression patterns of distinct TLRs in the developing mouse brain and lay the foundation for further investigation of the pathophysiological significance of these receptors for developmental processes in the central nervous system of vertebrates
Optimal error estimation for H(curl)-conforming p-interpolation in two dimensions
In this paper we prove an optimal error estimate for the H(curl)-conforming
projection based p-interpolation operator introduced in [L. Demkowicz and I.
Babuska, p interpolation error estimates for edge finite elements of variable
order in two dimensions, SIAM J. Numer. Anal., 41 (2003), pp. 1195-1208]. This
result is proved on the reference element (either triangle or square) K for
regular vector fields in H^r(curl,K) with arbitrary r>0. The formulation of the
result in the H(div)-conforming setting, which is relevant for the analysis of
high-order boundary element approximations for Maxwell's equations, is provided
as well
Introduction—Food Security and Food Waste Reduction: A Social Innovation Approach to Current Social, Environmental, and Political Concerns
This chapter presents the research rationale underpinning the book. It addresses the intertwining challenges of food security and surplus food management, discussing recent data and literature. It also presents how social innovation is conceptualized in the book as the theoretical framework to analyse partnerships between business and non-profit organisations in managing food surplus. The methodology of the research is also detailed, along with the book structure
Pathogenic huntingtin inhibits fast axonal transport by activating JNK3 and phosphorylating kinesin
Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Nature America for personal use, not for redistribution. The definitive version was published in Nature Neuroscience 12 (2009): 864-871, doi:10.1038/nn.2346.Selected vulnerability of neurons in Huntington’s disease (HD) suggests alterations in a cellular
process particularly critical for neuronal function. Supporting this idea, pathogenic Htt (polyQ-Htt)
inhibits fast axonal transport (FAT) in various cellular and animal HD models (mouse and squid),
but the molecular basis of this effect remains unknown. Here we show that polyQ-Htt inhibits FAT
through a mechanism involving activation of axonal JNK. Accordingly, increased activation of JNK
was observed in vivo in cellular and animal HD models. Additional experiments indicate that
polyQ-Htt effects on FAT are mediated by the neuron-specific JNK3, and not ubiquitously
expressed JNK1, providing a molecular basis for neuron-specific pathology in HD. Mass
spectrometry identified a residue in the kinesin-1 motor domain phosphorylated by JNK3, and this
modification reduces kinesin-1 binding to microtubules. These data identify JNK3 as a critical
mediator of polyQ-Htt toxicity and provides a molecular basis for polyQ-Htt-induced inhibition of
FAT.This work was supported by 2007/2008 MBL summer fellowship to GM; an HDSA
grant to GM; NIH grants MH066179 to GB; and ALSA, Muscular Dystrophy Association, and NIH
(NS23868, NS23320, NS41170) grants to STB
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