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Special opportunities for conserving cultural and biological diversity: The co-occurrence of Indigenous languages and UNESCO Natural World Heritage Sites
Recent research indicates that speakers of Indigenous languages often live in or near United Nations Educational, Scientific, and Cultural Organization (UNESCO) Natural World Heritage Sites (WHSs). Because language is a key index of cultural diversity, examining global patterns of co-occurrence between languages and these sites provides a means of identifying opportunities to conserve both culture and nature, especially where languages, WHSs, or both are recognized as endangered. This paper summarizes instances when Indigenous languages share at least part of their geographic extent with Natural WHSs. We consider how this co-occurrence introduces the potential to coordinate conservation of nature and sociocultural systems at these localities, particularly with respect to the recently issued UNESCO policy on engaging Indigenous people and the forthcoming International Year of Indigenous Languages. The paper concludes by discussing how the presence of Indigenous people at UNESCO Natural WHSs introduces important opportunities for co-management that enable resident Indigenous people to help conserve their language and culture along with the natural settings where they occur. We discuss briefly the example of Australia as a nation exploring opportunities for employing and strengthening such coordinated conservation efforts
On an explicit finite difference method for fractional diffusion equations
A numerical method to solve the fractional diffusion equation, which could
also be easily extended to many other fractional dynamics equations, is
considered. These fractional equations have been proposed in order to describe
anomalous transport characterized by non-Markovian kinetics and the breakdown
of Fick's law. In this paper we combine the forward time centered space (FTCS)
method, well known for the numerical integration of ordinary diffusion
equations, with the Grunwald-Letnikov definition of the fractional derivative
operator to obtain an explicit fractional FTCS scheme for solving the
fractional diffusion equation. The resulting method is amenable to a stability
analysis a la von Neumann. We show that the analytical stability bounds are in
excellent agreement with numerical tests. Comparison between exact analytical
solutions and numerical predictions are made.Comment: 22 pages, 6 figure
Integral equations of a cohesive zone model for history-dependent materials and their numerical solution
A nonlinear history-dependent cohesive zone (CZ) model of quasi-static crack propagation in
linear elastic and viscoelastic materials is presented. The viscoelasticity is described by a linear
Volterra integral operator in time. The normal stress on the CZ satisfies the history-dependent yield
condition, given by a nonlinear Abel-type integral operator. The crack starts propagating, breaking
the CZ, when the crack tip opening reaches a prescribed critical value. A numerical algorithm for
computing the evolution of the crack and CZ in time is discussed along with some numerical
results
Memory-induced anomalous dynamics: emergence of diffusion, subdiffusion, and superdiffusion from a single random walk model
We present a random walk model that exhibits asymptotic subdiffusive,
diffusive, and superdiffusive behavior in different parameter regimes. This
appears to be the first instance of a single random walk model leading to all
three forms of behavior by simply changing parameter values. Furthermore, the
model offers the great advantage of analytic tractability. Our model is
non-Markovian in that the next jump of the walker is (probabilistically)
determined by the history of past jumps. It also has elements of intermittency
in that one possibility at each step is that the walker does not move at all.
This rich encompassing scenario arising from a single model provides useful
insights into the source of different types of asymptotic behavior
L\'evy-Schr\"odinger wave packets
We analyze the time--dependent solutions of the pseudo--differential
L\'evy--Schr\"odinger wave equation in the free case, and we compare them with
the associated L\'evy processes. We list the principal laws used to describe
the time evolutions of both the L\'evy process densities, and the
L\'evy--Schr\"odinger wave packets. To have self--adjoint generators and
unitary evolutions we will consider only absolutely continuous, infinitely
divisible L\'evy noises with laws symmetric under change of sign of the
independent variable. We then show several examples of the characteristic
behavior of the L\'evy--Schr\"odinger wave packets, and in particular of the
bi-modality arising in their evolutions: a feature at variance with the typical
diffusive uni--modality of both the L\'evy process densities, and the usual
Schr\"odinger wave functions.Comment: 41 pages, 13 figures; paper substantially shortened, while keeping
intact examples and results; changed format from "report" to "article";
eliminated Appendices B, C, F (old names); shifted Chapters 4 and 5 (old
numbers) from text to Appendices C, D (new names); introduced connection
between Relativistic q.m. laws and Generalized Hyperbolic law
Polymer translocation through a nanopore - a showcase of anomalous diffusion
The translocation dynamics of a polymer chain through a nanopore in the
absence of an external driving force is analyzed by means of scaling arguments,
fractional calculus, and computer simulations. The problem at hand is mapped on
a one dimensional {\em anomalous} diffusion process in terms of reaction
coordinate (i.e. the translocated number of segments at time ) and shown
to be governed by an universal exponent whose
value is nearly the same in two- and three-dimensions. The process is described
by a {\em fractional} diffusion equation which is solved exactly in the
interval with appropriate boundary and initial conditions. The
solution gives the probability distribution of translocation times as well as
the variation with time of the statistical moments: , and which provide full description of the diffusion process. The
comparison of the analytic results with data derived from extensive Monte Carlo
(MC) simulations reveals very good agreement and proves that the diffusion
dynamics of unbiased translocation through a nanopore is anomalous in its
nature.Comment: 5 pages, 3 figures, accepted for publication in Phys. Rev.
Candida Transmission and Sexual Behaviors as Risks for a Repeat Episode of Candida Vulvovaginitis
Objective: To assess associations between female and male factors and the risk of recurring Candida vulvovaginitis. Methods: A prospective cohort study of 148 women with Candida vulvovaginitis and 78 of their male sexual partners was conducted at two primary care practices in the Ann Arbor, Michigan, area. Results: Thirty-three of 148 women developed at least one further episode of Candida albicans vulvovaginitis within 1 year of follow-up. Cultures of Candida species from various sites of the woman (tongue, feces, vulva, and vagina) and from her partner (tongue, feces, urine, and semen) did not predict recurrences. Female factors associated with recurrence included recent masturbating with saliva (hazard ratio 2.66 [95% CI 1.17-6.06]) or cunnilingus (hazard ratio 2.94 [95% CI 1.12-7.68]) and ingestion of two or more servings of bread per day (p ≤ 0.05). Male factors associated with recurrences in the woman included history of the male masturbating with saliva in the previous month (hazard ratio 3.68 [95% CI 1.24-10.87]) and lower age at first intercourse (hazard ratio 0.83 [95% CI 0.71-0.96]). Conclusions: Sexual behaviors, rather than the presence of Candida species at various body locations of the male partner, are associated with recurrences of C. albicans vulvovaginitis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63382/1/154099903322643901.pd
Spatially fractional-order viscoelasticity, non-locality and a new kind of anisotropy
Spatial non-locality of space-fractional viscoelastic equations of motion is
studied. Relaxation effects are accounted for by replacing second-order time
derivatives by lower-order fractional derivatives and their generalizations. It
is shown that space-fractional equations of motion of an order strictly less
than 2 allow for a new kind anisotropy, associated with angular dependence of
non-local interactions between stress and strain at different material points.
Constitutive equations of such viscoelastic media are determined. Explicit
fundamental solutions of the Cauchy problem are constructed for some cases
isotropic and anisotropic non-locality
Mesoscopic description of reactions under anomalous diffusion: A case study
Reaction-diffusion equations deliver a versatile tool for the description of
reactions in inhomogeneous systems under the assumption that the characteristic
reaction scales and the scales of the inhomogeneities in the reactant
concentrations separate. In the present work we discuss the possibilities of a
generalization of reaction-diffusion equations to the case of anomalous
diffusion described by continuous-time random walks with decoupled step length
and waiting time probability densities, the first being Gaussian or Levy, the
second one being an exponential or a power-law lacking the first moment. We
consider a special case of an irreversible or reversible A ->B conversion and
show that only in the Markovian case of an exponential waiting time
distribution the diffusion- and the reaction-term can be decoupled. In all
other cases, the properties of the reaction affect the transport operator, so
that the form of the corresponding reaction-anomalous diffusion equations does
not closely follow the form of the usual reaction-diffusion equations
Current and universal scaling in anomalous transport
Anomalous transport in tilted periodic potentials is investigated within the
framework of the fractional Fokker-Planck dynamics and the underlying
continuous time random walk. The analytical solution for the stationary,
anomalous current is obtained in closed form. We derive a universal scaling law
for anomalous diffusion occurring in tilted periodic potentials. This scaling
relation is corroborated with precise numerical studies covering wide parameter
regimes and different shapes for the periodic potential, being either symmetric
or ratchet-like ones
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