781 research outputs found
Corrections to Gravity due to a Sol Manifold Extra Dimensional Space
The corrections to the gravitational potential due to a Sol extra dimensional
compact manifold, denoted as , are studied. The total spacetime is of
the form . The range of the Sol corrections is investigated
and compared to the range of the corrections.Comment: 13 pages, 10 figures, published versio
Seasonal variation and impact of waste-water lagoons as larval habitat on the population dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at two dairy farms in northern California.
The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012- to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the "overwintering" of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and dispersal of Culicoides midges is essential for the creation of models to predict BTV infection of livestock and to develop sound abatement strategies
On multiplicities in length spectra of arithmetic hyperbolic three-orbifolds
Asymptotic laws for mean multiplicities of lengths of closed geodesics in
arithmetic hyperbolic three-orbifolds are derived. The sharpest results are
obtained for non-compact orbifolds associated with the Bianchi groups SL(2,o)
and some congruence subgroups. Similar results hold for cocompact arithmetic
quaternion groups, if a conjecture on the number of gaps in their length
spectra is true. The results related to the groups above give asymptotic lower
bounds for the mean multiplicities in length spectra of arbitrary arithmetic
hyperbolic three-orbifolds. The investigation of these multiplicities is
motivated by their sensitive effect on the eigenvalue spectrum of the
Laplace-Beltrami operator on a hyperbolic orbifold, which may be interpreted as
the Hamiltonian of a three-dimensional quantum system being strongly chaotic in
the classical limit.Comment: 29 pages, uuencoded ps. Revised version, to appear in NONLINEARIT
Salen-Based Amphiphiles:Directing Self-Assembly in Water by Metal Complexation
Tuning morphologies of selfâassembled structures in water is a major challenge. Herein we present a salenâbased amphiphile which, using complexation with distinct transition metal ions, allows to control effectively the selfâassembly morphology in water, as observed by CryoâTEM and confirmed by DLS measurements. Applying this strategy with various metal ions gives a broad spectrum of selfâassembled structures starting from the same amphiphilic ligand (from cubic structures to vesicles and micelles). Thermogravimetric analysis and electric conductivity measurements reveal a key role for water coordination apparently being responsible for the distinct assembly behavior.Supramolecular & Biomaterials Chemistr
Complete Genome Sequences of Virus Strains Isolated from Bottle A of the South African Live Attenuated Bluetongue Virus Vaccine
This is a report of the complete genome sequences of plaque-selected isolates of five virus strains included in bottle A of the South African Onderstepoort Biological Products commercial live attenuated bluetongue virus vaccine
On commensurable hyperbolic Coxeter groups
For Coxeter groups acting non-cocompactly but with finite covolume on real hyperbolic space Hn, new methods are presented to distinguish them up to (wide) commensurability. We exploit these ideas and determine the commensurability classes of all hyperbolic Coxeter groups whose fundamental polyhedra are pyramids over a product of two simplices of positive dimensions
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LER-LHC injector workshop summary, and super-Ferric fast cycling injector in the SPS tunnel
A Workshop on a Low Energy Ring (LER) in the LHC tunnel as a main injector was convened at CERN on October 11-12, 2006. We present the outline of the LER based on the presentations, and respond to the raised questions and discussions including the post-workshop studies. We also outline the possibility of using the LER accelerator technologies for the fast cycling injector accelerator in the SPS tunnel (SF-SPS)
A New Frequency-Luminosity Relation for Long GRBs?
We have studied power density spectra (PDS) of 206 long Gamma-Ray Bursts
(GRBs). We fitted the PDS with a simple power-law and extracted the exponent of
the power-law (alpha) and the noise-crossing threshold frequency (f_th). We
find that the distribution of the extracted alpha peaks around -1.4 and that of
f_th around 1 Hz. In addition, based on a sub-set of 58 bursts with known
redshifts, we show that the redshift-corrected threshold frequency is
positively correlated with the isotropic peak luminosity. The correlation
coefficient is 0.57 +/- 0.03.Comment: 9 pages, 17 figures, 1 table; Accepted for publication in MNRA
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