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Implication of Sialidases in Salmonella Infection: Genome Release of Sialidase Knockout Strains from Salmonella enterica Serovar Typhimurium LT2.
Sialidases, which are widely distributed in nature, cleave the α-ketosidic bond of terminal sialic acid residue. These emerging virulence factors degrade the host glycan. We report here the release of seven sialidase and one sialic acid transporter deletion in Salmonella enterica serovar Typhimurium strain LT2, which are important in cellular invasion during infection
Strongly birefringent cut-wire pair structure as negative index wave plates at THz frequencies
We report a new approach for the design and fabrication of thin wave plates
with high transmission in the terahertz (THz) regime. The wave plates are based
on strongly birefringent cut-wire pair metamaterials that exhibit refractive
indices of opposite signs for two orthogonal polarization components of an
incident wave. As specific examples, we fabricated and investigated a quarter-
and a half-wave plate that revealed a peak intensity transmittance of 74% and
58% at 1.34 THz and 1.3 THz, respectively. Furthermore, the half wave plate
displayed a maximum figure of merit (FOM) of 23 at 1.3 THz where the refractive
index was -1.7. This corresponds to one of the highest FOMs reported at THz
frequencies so far. The presented results evidence that negative index
materials enter an application stage in terms of optical components for the THz
technology.Comment: 4 pages, 3 figures, submitted to Appl. Phys. Let
Finding a Mate With No Social Skills
Sexual reproductive behavior has a necessary social coordination component as
willing and capable partners must both be in the right place at the right time.
While there are many known social behavioral adaptations to support solutions
to this problem, we explore the possibility and likelihood of solutions that
rely only on non-social mechanisms. We find three kinds of social organization
that help solve this social coordination problem (herding, assortative mating,
and natal philopatry) emerge in populations of simulated agents with no social
mechanisms available to support these organizations. We conclude that the
non-social origins of these social organizations around sexual reproduction may
provide the environment for the development of social solutions to the same and
different problems.Comment: 8 pages, 5 figures, GECCO'1
Stochastic integration in UMD Banach spaces
In this paper we construct a theory of stochastic integration of processes
with values in , where is a separable Hilbert space and
is a UMD Banach space (i.e., a space in which martingale differences are
unconditional). The integrator is an -cylindrical Brownian motion. Our
approach is based on a two-sided -decoupling inequality for UMD spaces due
to Garling, which is combined with the theory of stochastic integration of
-valued functions introduced recently by two of the authors.
We obtain various characterizations of the stochastic integral and prove
versions of the It\^{o} isometry, the Burkholder--Davis--Gundy inequalities,
and the representation theorem for Brownian martingales.Comment: Published at http://dx.doi.org/10.1214/009117906000001006 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Draft Genome Sequences of Campylobacter jejuni Strains That Cause Abortion in Livestock.
Campylobacter jejuni is an intestinal bacterium that can cause abortion in livestock. This publication announces the public release of 15 Campylobacter jejuni genome sequences from isolates linked to abortion in livestock. These isolates are part of the 100K Pathogen Genome Project and are from clinical cases at the University of California (UC) Davis
Stochastic evolution equations in UMD Banach spaces
We discuss existence, uniqueness, and space-time H\"older regularity for
solutions of the parabolic stochastic evolution equation dU(t) = (AU(t) +
F(t,U(t))) dt + B(t,U(t)) dW_H(t), t\in [0,\Tend], U(0) = u_0, where
generates an analytic -semigroup on a UMD Banach space and is a
cylindrical Brownian motion with values in a Hilbert space . We prove that
if the mappings and satisfy suitable Lipschitz conditions and is
\F_0-measurable and bounded, then this problem has a unique mild solution,
which has trajectories in C^\l([0,T];\D((-A)^\theta) provided
and satisfy \l+\theta<\frac12. Various extensions of this
result are given and the results are applied to parabolic stochastic partial
differential equations.Comment: Accepted for publication in Journal of Functional Analysi
Spin Coherence and N ESEEM Effects of Nitrogen-Vacancy Centers in Diamond with X-band Pulsed ESR
Pulsed ESR experiments are reported for ensembles of negatively-charged
nitrogen-vacancy centers (NV) in diamonds at X-band magnetic fields
(280-400 mT) and low temperatures (2-70 K). The NV centers in synthetic
type IIb diamonds (nitrogen impurity concentration ~ppm) are prepared with
bulk concentrations of cm to cm
by high-energy electron irradiation and subsequent annealing. We find that a
proper post-radiation anneal (1000C for 60 mins) is critically
important to repair the radiation damage and to recover long electron spin
coherence times for NVs. After the annealing, spin coherence times of T~ms at 5~K are achieved, being only limited by C nuclear spectral
diffusion in natural abundance diamonds. At X-band magnetic fields, strong
electron spin echo envelope modulation (ESEEM) is observed originating from the
central N nucleus. The ESEEM spectral analysis allows for accurate
determination of the N nuclear hypefine and quadrupole tensors. In
addition, the ESEEM effects from two proximal C sites (second-nearest
neighbor and fourth-nearest neighbor) are resolved and the respective C
hyperfine coupling constants are extracted.Comment: 10 pages, 5 figure
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