23,485 research outputs found
Optical Spectroscopic Survey of High-latitude WISE-selected Sources
We report on the results of an optical spectroscopic survey at high Galactic latitude (|b| ≥ 30°) of a sample of WISE-selected targets, grouped by WISE W1 (λ_eff = 3.4 μm) flux, which we use to characterize the sources WISE detected. We observed 762 targets in 10 disjoint fields centered on ultraluminous infrared galaxy candidates using DEIMOS on Keck II. We find 0.30 ± 0.02 galaxies arcmin–2 with a median redshift of z = 0.33 ± 0.01 for the sample with W1 ≥ 120 μJy. The foreground stellar densities in our survey range from 0.23 ± 0.07 arcmin–2 to 1.1 ± 0.1 arcmin–2 for the same sample. We obtained spectra that produced science grade redshifts for ≥90% of our targets for sources with W1 flux ≥120 μJy that also had an i-band flux gsim 18 μJy. We used this for targeting very preliminary data reductions available to the team in 2010 August. Our results therefore present a conservative estimate of what is possible to achieve using WISE's Preliminary Data Release for the study of field galaxies
Cross subclade immunity after one-year booster immunization with MF59®-adjuvanted A/H5N1 influenza vaccine in 6 month to 17 year-old children
Background: Since 2006 when the zoster vaccine was first icensed, one of the most commonly asked questions by patients nd clinicians has been "Should a patient with a history of herpes oster (HZ) receive the vaccine to prevent another episode?". The enefit of vaccinating immunocompetent patients who have had hingles has not been examined. The study assessed the association etween vaccination and the incidence of herpes zoster recurrence mong personswith a recent episode of clinically diagnosed herpes oster. Methods: This is a matched cohort study in Kaiser Permanente outhern California. Study populations were immunocompetent lderly≥ 60 years oldwith a recent episode of herpes zoster. Potenial recurrent HZ cases were identified electronically by ICD-9 code f 053.xx from outpatient, emergency, and inpatient files. Medcal records of electronically identified cases were retrieved and eviewed masked to vaccination status by an infectious disease pecialist using pre-specified review criteria. Incidence of recurent herpes zoster was compared between the vaccinated and the nvaccinated matched cohorts. The hazard ratio associated with accination was adjusted for a propensity score that accounted for otential confounders. Results: There were total 1,036 vaccinated and 5,180 unvacciated members included. Based on the clinically confirmed cases, he incidence of recurrent HZ among age <70 cohort was 0.99 (95% I, 0.02-5.54) and 2.20 (95% CI, 1.10-3.93) per 1,000 person-year
Life table analysis of Diaphorina citri (Hemiptera: Psyllidae) infesting sweet orange (Citrus sinensis) in São Paulo
An ecological life table for eggs and nymphs of Diaphorina citri Kuwayama (Hemiptera:
Psyllidae) was constructed with data obtained from orange orchards (Citrus sinensis Osbeck) in 2 regions of the State of São Paulo, over 4 generations in the period from XI-2006
to V-2007, comprising spring, summer, and fall seasons. Young growing shoots with D. citri
eggs present were identifed, and live individuals were counted until adult emergence. No
predatory arthropods were observed in association with D. citri eggs and nymphs during
the study. The mean parasitism of fourth- and ffth-instar nymphs by Tamarixia radiata
Waterston (Hymenoptera: Eulophidae) was 2.3%. The durations of the egg–adult period
were similar among the 4 generations, ranging from 18.0 to 24.7 d (at mean temperatures
ranging from 21.6 to 26.0 °C) and followed the temperature requirement models obtained
in the laboratory for D. citri. However, survival from the egg to the adult stage for the same
period varied considerably from 1.7 to 21.4%; the highest mortalities were observed in the
egg and small nymphal (frst- to thirdinstar) stages, which were considered to be key phases
for population growth of the pest.Uma tabela de vida ecológica foi construÃda para ovos e ninfas de Diaphorina citri Kuwayama (Hemiptera: Psyllidae) com dados obtidos em pomares de laranja (Citrus sinensis Osbeck) em 2 regiões do estado de São Paulo, com 4 gerações, no perÃodo de novembro de 2006
a maio de 2007, compreendendo as estações de primavera, verão e outono. Ramos jovens
em crescimento com a presença de ovos de D. citri foram identificados e os indivÃduos vivos
foram contados até a emergência dos adultos. Nenhum predador foi observado associado a
ovos e ninfas de D. citri durante o estudo. A taxa média de parasitismo de ninfas de quarto
e quinto Ãnstares por Tamarixia radiata Waterson (Hymenoptera: Eulophidae) foi de 2.3%.
A duração do perÃodo de ovo a adulto foi semelhante entre as quatro gerações, variando de
18.0 a 24.7 dias (com temperaturas médias de 21.6 a 26.0 °C) e seguiram os modelos de
exigencias térmicas obtidas em laboratório para D. citri. Todavia, a sobrevivencia de ovo
até o estágio adulto variou consideravelmente para o mesmo perÃodo, de 1.7 a 21.4%, sendo
que as maiores mortalidades foram observadas nos estágios de ovos e ninfas pequenas (de
primeiro a terceiro Ãnstares), as quais foram consideradas fases chaves para o crescimento
populacional desta praga.info:eu-repo/semantics/publishedVersio
Stable directions for small nonlinear Dirac standing waves
We prove that for a Dirac operator with no resonance at thresholds nor
eigenvalue at thresholds the propagator satisfies propagation and dispersive
estimates. When this linear operator has only two simple eigenvalues close
enough, we study an associated class of nonlinear Dirac equations which have
stationary solutions. As an application of our decay estimates, we show that
these solutions have stable directions which are tangent to the subspaces
associated with the continuous spectrum of the Dirac operator. This result is
the analogue, in the Dirac case, of a theorem by Tsai and Yau about the
Schr\"{o}dinger equation. To our knowledge, the present work is the first
mathematical study of the stability problem for a nonlinear Dirac equation.Comment: 62 page
Non-Ergodic Dynamics of the 2D Random-phase Sine-Gordon Model: Applications to Vortex-Glass Arrays and Disordered-Substrate Surfaces
The dynamics of the random-phase sine-Gordon model, which describes 2D
vortex-glass arrays and crystalline surfaces on disordered substrates, is
investigated using the self-consistent Hartree approximation. The
fluctuation-dissipation theorem is violated below the critical temperature T_c
for large time t>t* where t* diverges in the thermodynamic limit. While above
T_c the averaged autocorrelation function diverges as Tln(t), for T<T_c it
approaches a finite value q* proportional to 1/(T_c-T) as q(t) = q* -
c(t/t*)^{-\nu} (for t --> t*) where \nu is a temperature-dependent exponent. On
larger time scales t > t* the dynamics becomes non-ergodic. The static
correlations behave as Tln{x} for T>T_c and for T<T_c when x < \xi* with \xi*
proportional to exp{A/(T_c-T)}. For scales x > \xi*, they behave as (T/m)ln{x}
where m is approximately T/T_c near T_c, in general agreement with the
variational replica-symmetry breaking approach and with recent simulations of
the disordered-substrate surface. For strong- coupling the transition becomes
first-order.Comment: 12 pages in LaTeX, Figures available upon request, NSF-ITP 94-10
Long time dynamics and coherent states in nonlinear wave equations
We discuss recent progress in finding all coherent states supported by
nonlinear wave equations, their stability and the long time behavior of nearby
solutions.Comment: bases on the authors presentation at 2015 AMMCS-CAIMS Congress, to
appear in Fields Institute Communications: Advances in Applied Mathematics,
Modeling, and Computational Science 201
Near-Equilibrium Dynamics of Crystalline Interfaces with Long-Range Interactions in 1+1 Dimensional Systems
The dynamics of a one-dimensional crystalline interface model with long-range
interactions is investigated. In the absence of randomness, the linear response
mobility decreases to zero when the temperature approaches the roughening
transition from above, in contrast to a finite jump at the critical point in
the Kosterlitz-Thouless (KT) transition. In the presence of substrate disorder,
there exists a phase transition into a low-temperature pinning phase with a
continuously varying dynamic exponent . The expressions for the non-linear
response mobility of a crystalline interface in both cases are also derived.Comment: 14 Pages, Revtex3.0, accepted to be published in Phys. Rev. E Rapid
Communicatio
Spontaneous Crystallization of Skyrmions and Fractional Vortices in the Fast-rotating and Rapidly-quenched Spin-1 Bose-Einstein Condensates
We investigate the spontaneous generation of crystallized topological defects
via the combining effects of fast rotation and rapid thermal quench on the
spin-1 Bose-Einstein condensates. By solving the stochastic projected
Gross-Pitaevskii equation, we show that, when the system reaches equilibrium, a
hexagonal lattice of skyrmions, and a square lattice of half-quantized vortices
can be formed in a ferromagnetic and antiferromagnetic spinor BEC, respetively,
which can be imaged by using the polarization-dependent phase-contrast method
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