An apertureless near-field microscope for fluorescence imaging

We describe an apertureless near field microscope for imaging fluorescent samples. Optical contrast is generated by exploiting fluorescent quenching near a metallized atomic force microscope tip. This microscope has been used to image fluorescent latex beads with subdiffraction limit resolution. The use of fluorescence allows us to prove that the contrast mechanism is indeed spectroscopic in origin

Challenges in New Physics searches in top-like events at the LHC

The prospects of exploring physics beyond the standard model involving top quarks and top-like signals at the LHC based on Monte Carlo simulations at √s = 14 and 10TeV are reviewed. A special attention is given to results that can be expected for the early LHC running in 2010-2011. Consequently, the first section deals with the implications of having a center-of-mass energy lower than what was simulated, √s = 7TeV, for the first years of the LHC running. This will be done qualitatively by discussing the impact on the cross section of various production processes. Following this discussion, several searches for physics Beyond the standard model that are related to the top quark are described: top-antitop resonances, 4th generation of quarks, top charge, W polarization, anomalous Wtb vertex coupling, top-antitop spin correlation, and flavor changing neutral current. Their order of appearance goes from lower to higher integrated luminosity needed to obtain meaningful results out of each analysis

М. Ф. ФОН ДІТМАР – ЯСКРАВИЙПРЕДСТАВНИК ГІРНИЧОПРОМИСЛОВОЇ БУРЖУАЗІЇ ПІВДНЯ УКРАЇНИ(ОСТАННЯ ЧВЕРТЬ ХІХ– ПОЧАТОК ХХ СТ.)

В статті розглянуто постать відомого підприємця, науковця і суспільного діячаМ. Ф. фон Дітмара, визначено основні напрями його діяльності наПівдні Українив останній чверті ХІХ – на початку ХХ ст.The article considers the person of famous businessman, scientist and social activistM. F. von Ditmar, determines themain directions of his activity in SouthernUkraine in the last quarter ofXIX – the beginning ofXXcenturies

Rigorous numerics in floquet theory: Computing stable and unstable bundles of periodic orbits

In this paper, a rigorous method to compute Floquet normal forms of fundamental matrix solutions of nonautonomous linear differential equations with periodic coefficients is introduced. The Floquet normal form of a fundamental matrix solution F(t) is a canonical decomposition of the form F(t) = Q(t)eRt, where Q(t) is a real periodic matrix and R is a constant matrix. To rigorously compute the Floquet normal form, the idea is to use the regularity of Q(t) and to simultaneously solve for R and Q(t) with the contraction mapping theorem in a Banach space of rapidly decaying coefficients. The explicit knowledge of R and Q can then be used to construct, in a rigorous computer-assisted way, stable and unstable bundles of periodic orbits of vector fields. The new proposed method does not require rigorous numerical integration of the ODE

African-American patients with cancer Talking About Clinical Trials (TACT) with oncologists during consultations: evaluating the efficacy of tailored health messages in a randomised controlled trial—the TACT study protocol

Introduction Low rates of accrual of African-American (AA) patients with cancer to therapeutic clinical trials (CTs) represent a serious and modifiable racial disparity in healthcare that impedes the development of promising cancer therapies. Suboptimal physician–patient consultation communication is a barrier to the accrual of patients with cancer of any race, but communication difficulties are compounded with AA patients. Providing tailored health messages (THM) to AA patients and their physician about CTs has the potential to improve communication, lower barriers to accrual and ameliorate health disparities. Objective (1) Demonstrate the efficacy of THM to increase patient activation as measured by direct observation. (2) Demonstrate the efficacy of THM to improve patient outcomes associated with barriers to AA participation. (3) Explore associations among preconsultation levels of: (A) trust in medical researchers, (B) knowledge and attitudes towards CTs, (C) patient-family member congruence in decision-making, and (D) involvement/information preferences, and group assignment. Methods and analysis First, using established methods, we will develop THM materials. Second, the efficacy of the intervention is determined in a 2 by 2 factorial randomised controlled trial to test the effectiveness of (1) providing 357 AA patients with cancer with THM with 2 different ‘depths’ of tailoring and (2) either providing feedback to oncologists about the patients\u27 trial THM or not. The primary analysis compares patient engaged communication in 4 groups preconsultation and postconsultation. Ethics and dissemination This study was approved by the Virginia Commonwealth University Institutional Review Board. To facilitate use of the THM intervention in diverse settings, we will convene ‘user groups’ at 3 major US cancer centres. To facilitate dissemination, we will post all materials and the implementation guide in publicly available locations

Parameterization of Invariant Manifolds for Periodic Orbits I: Efficient Numerics via the Floquet Normal Form

We present an efficient numerical method for computing Fourier-Taylor expansions of (un)stable manifolds associated with hyperbolic periodic orbits. Three features of the method are that (1) we obtain accurate representation of the invariant manifold as well as the dynamics on the manifold, (2) it admits natural a posteriori error analysis, and (3) it does not require numerically integrating the vector field. Our approach is based on the parameterization method for invariant manifolds, and studies a certain partial differential equation which characterizes a chart map of the manifold. The method requires only that some mild nonresonance conditions hold. The novelty of the present work is that we exploit the Floquet normal form in order to efficiently compute the Fourier-Taylor expansion. A number of example computations are given including manifolds in phase space dimension as high as ten and manifolds which are two and three dimensional. We also discuss computations of cycle-to-cycle connecting orbits which exploit these manifolds

Scanning apertureless fluorescence microscope

We describe a near-field apertureless fluorescence microscope, capable of imaging fluorescent latex beads with subwavelength precision. The instrument is based on a home- built tapping-mode atomic-force microscope, to which an inverted optical microscope was added. The fact that the wavelength of the fluorescence that we observe is different from the wavelength of the illumination allows for a relatively straightforward detection mechanism. Sample images are presented, along with evidence that the observe effect is of optical origin