12,579 research outputs found
Horospherical surfaces of curves in hyperbolic space
We consider the contact between curves and horospheres in Hyperbolic 3-space as an application of singularity theory of functions. We define the osculating horosphere of the curve. We also define the horospherical surface of the curve whose singular points correspond to the locus of polar vectors of osculating horospheres of the curve. One of the main results is to give a generic classification of singularities of horospherical surface of curves
The cosmological origin of Higgs particles
A proposal of the cosmological origin of Higgs particles is given. We show,
that the Higgs field could be created from the vacuum quantum conformal
fluctuation of Anti-de Sitter space-time, the spontaneous breaking of vacuum
symmetry, and the mass of Higgs particle are related to the cosmological
constant of our universe,especially the theoretical estimated mass m of
Higgs particles is m =.Comment: 7 pages,no figure
The hyperbolic Gauss-Bonnet type theorem
We show that the Gauss-Bonnet type theorem holds for the hyperbolic Gauss-Kronecker curvature of a closed orientable even dimensional hypersurface in hyperbolic space. We also give detailed studies for surfaces
4-manifolds and topological modular forms
We build a connection between topology of smooth 4-manifolds and the theory of topological modular forms by considering topologically twisted compactification of 6d (1,0) theories on 4-manifolds with flavor symmetry backgrounds. The effective 2d theory has (0,1) supersymmetry and, possibly, a residual flavor symmetry. The equivariant topological Witten genus of this 2d theory then produces a new invariant of the 4-manifold equipped with a principle bundle, valued in the ring of equivariant weakly holomorphic (topological) modular forms. We describe basic properties of this map and present a few simple examples. As a byproduct, we obtain some new results on 't Hooft anomalies of 6d (1,0) theories and a better understanding of the relation between 2d (0,1) theories and TMF spectra
A unified approach to combinatorial key predistribution schemes for sensor networks
There have been numerous recent proposals for key predistribution schemes for wireless sensor networks based on various types of combinatorial structures such as designs and codes. Many of these schemes have very similar properties and are analysed in a similar manner. We seek to provide a unified framework to study these kinds of schemes. To do so, we define a new, general class of designs, termed “partially balanced t-designs”, that is sufficiently general that it encompasses almost all of the designs that have been proposed for combinatorial key predistribution schemes. However, this new class of designs still has sufficient structure that we are able to derive general formulas for the metrics of the resulting key predistribution schemes. These metrics can be evaluated for a particular scheme simply by substituting appropriate parameters of the underlying combinatorial structure into our general formulas. We also compare various classes of schemes based on different designs, and point out that some existing proposed schemes are in fact identical, even though their descriptions may seem different. We believe that our general framework should facilitate the analysis of proposals for combinatorial key predistribution schemes and their comparison with existing schemes, and also allow researchers to easily evaluate which scheme or schemes present the best combination of performance metrics for a given application scenario
The Expression and Roles of Nde1 and Ndel1 in the Adult Mammalian Central Nervous System
Open Access funded by Wellcome Trust Under a Creative Commons license Acknowledgments We thank Prof Angelo Sementilli, Department of Pathology, Universidade Metropolitana de Santos, SP, Brazil, for the human sample collection. This study is funded by Scottish Universities Life Sciences Alliance (HR07019 to S. Shen and C.D. McCaig), Medical Research Scotland (384 FRG to B. Lang, United Kingdom), Tenovus Scotland (G12/25 to B. Lang), Sino-UK Higher Education Research Partnership for PhD Studies (C.D. McCaig and Y.Q. Ding) and Wellcome Trust (WT081633MA-NCE to P.J.A. McCaffery, United Kingdom).Peer reviewedPublisher PD
Neutrino masses in the economical 3-3-1 model
We show that, in frameworks of the economical 3-3-1 model, the suitable
pattern of neutrino masses arises from the three quite different sources - the
lepton-number conserving, the spontaneous lepton-number breaking and the
explicit lepton-number violating, widely ranging over the mass scales including
the GUT one: , , \om\sim
O(1) \mathrm{TeV} and . At
the tree-level, the model contains three Dirac neutrinos: one massless, two
large with degenerate masses in the order of the electron mass. At the one-loop
level, the left-handed and right-handed neutrinos obtain Majorana masses
in orders of and degenerate in
, while the Dirac masses get a large reduction down to
scale through a finite mass renormalization. In this model, the contributions
of new physics are strongly signified, the degenerations in the masses and the
last hierarchy between the Majorana and Dirac masses can be completely removed
by heavy particles. All the neutrinos get mass and can fit the data.Comment: 15 pages, 8 figure
Proton Heating in Solar Wind Compressible Turbulence with Collisions between Counter-propagating Waves
Magnetohydronamic turbulence is believed to play a crucial role in heating
the laboratorial, space, and astrophysical plasmas. However, the precise
connection between the turbulent fluctuations and the particle kinetics has not
yet been established. Here we present clear evidence of plasma turbulence
heating based on diagnosed wave features and proton velocity distributions from
solar wind measurements by the Wind spacecraft. For the first time, we can
report the simultaneous observation of counter-propagating magnetohydrodynamic
waves in the solar wind turbulence. Different from the traditional paradigm
with counter-propagating Alfv\'en waves, anti-sunward Alfv\'en waves (AWs) are
encountered by sunward slow magnetosonic waves (SMWs) in this new type of solar
wind compressible turbulence. The counter-propagating AWs and SWs correspond
respectively to the dominant and sub-dominant populations of the imbalanced
Els\"asser variables. Nonlinear interactions between the AWs and SMWs are
inferred from the non-orthogonality between the possible oscillation direction
of one wave and the possible propagation direction of the other. The associated
protons are revealed to exhibit bi-directional asymmetric beams in their
velocity distributions: sunward beams appearing in short and narrow patterns
and anti-sunward broad extended tails. It is suggested that multiple types of
wave-particle interactions, i.e., cyclotron and Landau resonances with AWs and
SMWs at kinetic scales, are taking place to jointly heat the protons
perpendicularly and parallel
Theories for influencer identification in complex networks
In social and biological systems, the structural heterogeneity of interaction
networks gives rise to the emergence of a small set of influential nodes, or
influencers, in a series of dynamical processes. Although much smaller than the
entire network, these influencers were observed to be able to shape the
collective dynamics of large populations in different contexts. As such, the
successful identification of influencers should have profound implications in
various real-world spreading dynamics such as viral marketing, epidemic
outbreaks and cascading failure. In this chapter, we first summarize the
centrality-based approach in finding single influencers in complex networks,
and then discuss the more complicated problem of locating multiple influencers
from a collective point of view. Progress rooted in collective influence
theory, belief-propagation and computer science will be presented. Finally, we
present some applications of influencer identification in diverse real-world
systems, including online social platforms, scientific publication, brain
networks and socioeconomic systems.Comment: 24 pages, 6 figure
A field investigation of the thermal environment and adaptive thermal behavior in bedrooms in different climate regions in China
Sleep thermal environments substantially impact sleep quality. To study the sleep thermal environment and thermal comfort in China, this study carried out on‐site monitoring of thermal environmental parameters in peoples’ homes, including 166 households in five climate zones, for one year. A questionnaire survey on sleep thermal comfort and adaptive behavior was also conducted. The results showed that the indoor temperature for sleep in northern China was more than 4°C higher than that in southern China in winter, while the indoor temperatures for sleep were similar in summer. Furthermore, 70% of people were satisfied with their sleep thermal environment. Due to the use of air conditioning and window opening in various areas in summer, people were satisfied with their sleep thermal environments. Due to the lack of central heating in the southern region in winter, people feel cold and their sleep thermal environment needs further improvement. The bedding insulation in summer and winter in northern China was 1.83clo and 2.67clo, respectively, and in southern China was 2.21clo and 3.17clo, respectively. Both northern China and southern China used air conditioning only in summer. People in southern China opened their windows all year, while those in northern China opened their windows during the summer and transitional periods
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