Generalized north-south dynamics on the space of geodesic currents

We prove uniform north-south dynamics type results for the action of $\varphi\in Out(F_{N})$ on the space of projectivized geodesic currents $\mathbb{P}Curr(S)=\mathbb{P}Curr(F_{N})$, where $\varphi$ is induced by a pseudo-Anosov homeomorphism on a compact surface S with boundary such that $\pi_{1}(S)=F_{N}$. As an application, we show that for a subgroup $H\le Out(F_N)$, containing an iwip, either $H$ contains a hyperbolic iwip or $H$ is contained in the image in $Out(F_N)$ of the mapping class group of a surface with a single boundary component.Comment: 20 pages, 2 figures, v3: Minor correction

An intersection functional on the space of subset currents on a free group

Kapovich and Nagnibeda introduced the space $\mathcal{S} {\rm Curr}(F_N)$ of subset currents on a free group $F_N$ of rank $N\geq 2$, which can be thought of as a measure-theoretic completion of the set of all conjugacy classes of finitely generated subgroups of $F_N$. We define a product $\mathcal{N} (H,K)$ of two finitely generated subgroups $H$ and $K$ of $F_N$ by the sum of the reduced rank $\overline{\rm rk}(H\cap gKg^{-1})$ over all double cosets $HgK\ (g\in F_N)$, and extend the product$\mathcal{N}$to a continuous symmetric$\mathbb{R}_{\geq 0}$-bilinear functional$\mathcal{N} \colon \mathcal{S} {\rm Curr} (F_N)\times \mathcal{S} {\rm Curr} (F_N)\to \mathbb {R}_{\geq 0}$. We also give an answer to a question presented by Kapovich and Nagnibeda. The definition of$\mathcal{N}$originates in the Strengthened Hanna Neumann Conjecture, which has been proven by Mineyev and can be stated as follows:$\mathcal{N} (H,K)\leq \overline{{\rm rk}} (H) \overline{\rm rk} (K)$holds for any finitely generated subgroups$H$and$K$of$F_N$. As a corollary to our theorem, this inequality is generalized to the inequality for subset currents.Comment: 27 pages (updated version). arXiv admin note: text overlap with arXiv:1105.5742 by other author

Colloidal particle motion as a diagnostic of DNA conformational transitions

Tethered particle motion is an experimental technique to monitor conformational changes in single molecules of DNA in real time, by observing the position fluctuations of a micrometer-size particle attached to the DNA. This article reviews some recent work on theoretical problems inherent in the interpretation of TPM experiments, both in equilibrium and dynamical aspects.Comment: 19pp. Accepted for publication in Curr Op Colloid Interf Scienc

Evidence for Bound and Free Water Species in the Hydration Shell of an Aqueous Micelle

Our atomistic molecular dynamics simulations reveal the existence of bound and free water molecules in the hydration layer of an aqueous micelle. The bound water molecules can be either singly or doubly hydrogen bonded to the polar head group on the surface of the micelle. The ratio of bound to free water is found to be approximately equal to 9:1 at 300 K.Comment: 7 pages and 3 figures. Submitted to Curr. Sci.(Ind. Acad. Sci.

Curr Environ Health Rep

Purpose of ReviewWe offer an in-depth discussion of the time-varying confounding and selection bias mechanisms that give rise to the healthy worker survivor effect (HWSE).Recent FindingsIn this update of an earlier review, we distinguish between the mechanisms collectively known as the HWSE and the statistical bias that can result. This discussion highlights the importance of identifying both the target parameter and the target population for any research question in occupational epidemiology. Target parameters can correspond to hypothetical workplace interventions; we explore whether these target parameters\u2019 true values reflect the etiologic effect of an exposure on an outcome or the potential impact of enforcing an exposure limit in a more realistic setting. If a cohort includes workers hired before the start of follow-up, HWSE mechanisms can limit the transportability of the estimates to other target populations.SummaryWe summarize recent publications that applied g-methods to control for the HWSE, focusing on their target parameters, target populations, and hypothetical interventions.R56 AG026291/AG/NIA NIH HHS/United StatesT42 OH008429/OH/NIOSH CDC HHS/United States2018-09-01T00:00:00Z28712046PMC5693751vault:2740

Advances in Lasers for the Treatment of Stones-a Systematic Review

PURPOSE OF REVIEW: Laser lithotripsy is increasingly used worldwide and is a continuously evolving field with new and extensive research being published every year. RECENT FINDINGS: Variable pulse length Ho:YAG lithotripters allow new lithotripsy parameters to be manipulated, and there is an effort to integrate new technologies into lithotripters. Pulsed thulium lasers seem to be a viable alternative to holmium lasers. The performance of similar laser fibers varies from manufacturer to manufacturer. Special laser fibers and "cleaving only" fiber tip preparation can be beneficial for the lithotripsy procedure. Different laser settings and the surgical technique employed can have significant impact on the success of laser lithotripsy. When safely done, complications of laser lithotripsy are rare and concern the endoscopic nature of procedure, not the technology itself, making laser lithotripsy one of the safest tools in urology. Laser lithotripsy has had several new developments and more insight has been gained in recent years with many more advances expected in the future.info:eu-repo/semantics/publishedVersio

Theoretical models of ferromagnetic III-V semiconductors

Recent materials research has advanced the maximum ferromagnetic transition temperature in semiconductors containing magnetic elements toward room temperature. Reaching this goal would make information technology applications of these materials likely. In this article we briefly review the status of work over the past five years which has attempted to achieve a theoretical understanding of these complex magnetic systems. The basic microscopic origins of ferromagnetism in the (III,Mn)V compounds that have the highest transition temperatures appear to be well understood, and efficient computation methods have been developed which are able to model their magnetic, transport, and optical properties. However many questions remain.Comment: 4 pages, 4 figures, review, to be published in Curr. Appl. Phy