3,579 research outputs found

    K -> pi pi and a light scalar meson

    Full text link
    We explore the Delta-I= 1/2 rule and epsilon'/epsilon in K -> pi pi transitions using a Dyson-Schwinger equation model. Exploiting the feature that QCD penguin operators direct K^0_S transitions through 0^{++} intermediate states, we find an explanation of the enhancement of I=0 K -> pi pi transitions in the contribution of a light sigma-meson. This mechanism also affects epsilon'/epsilon.Comment: 7 pages, REVTE

    Pruning Algorithms for Pretropisms of Newton Polytopes

    Full text link
    Pretropisms are candidates for the leading exponents of Puiseux series that represent solutions of polynomial systems. To find pretropisms, we propose an exact gift wrapping algorithm to prune the tree of edges of a tuple of Newton polytopes. We prefer exact arithmetic not only because of the exact input and the degrees of the output, but because of the often unpredictable growth of the coordinates in the face normals, even for polytopes in generic position. We provide experimental results with our preliminary implementation in Sage that compare favorably with the pruning method that relies only on cone intersections.Comment: exact, gift wrapping, Newton polytope, pretropism, tree pruning, accepted for presentation at Computer Algebra in Scientific Computing, CASC 201

    Categorization of indoor places by combining local binary pattern histograms of range and reflectance data from laser range finders

    Get PDF
    This paper presents an approach to categorize typical places in indoor environments using 3D scans provided by a laser range finder. Examples of such places are offices, laboratories, or kitchens. In our method, we combine the range and reflectance data from the laser scan for the final categorization of places. Range and reflectance images are transformed into histograms of local binary patterns and combined into a single feature vector. This vector is later classified using support vector machines. The results of the presented experiments demonstrate the capability of our technique to categorize indoor places with high accuracy. We also show that the combination of range and reflectance information improves the final categorization results in comparison with a single modality

    Two dimensionality in quasi one-dimensional cobalt oxides

    Full text link
    By means of muon spin rotation and relaxation (μ+\mu^+SR) techniques, we have investigated the magnetism of quasi one-dimensional (1D) cobalt oxides AEn+2AE_{n+2}Con+1_{n+1}O3n+3_{3n+3} (AEAE=Ca, Sr and Ba, nn=1, 2, 3, 5 and \infty), in which the 1D CoO3_3 chain is surrounded by six equally spaced chains forming a triangular lattice in the abab-plane, using polycrystalline samples, from room temperature down to 1.8 K. For the compounds with nn=1 - 5, transverse field μ+\mu^+SR experiments showed the existence of a magnetic transition below \sim100 K. The onset temperature of the transition (TconT_{\rm c}^{\rm on}) was found to decrease with nn; from 100 K for nn=1 to 60 K for nn=5. A damped muon spin oscillation was observed only in the sample with nn=1 (Ca3_3Co2_2O6_6), whereas only a fast relaxation obtained even at 1.8 K in the other three samples. In combination with the results of susceptibility measurements, this indicates that a two-dimensional short-range antiferromagnetic (AF) order appears below TconT_{\rm c}^{\rm on} for all compounds with nn=1 - 5; but quasi-static long-range AF order formed only in Ca3_3Co2_2O6_6, below 25 K. For BaCoO3_3 (nn=\infty), as TT decreased from 300 K, 1D ferromagnetic (F) order appeared below 53 K, and a sharp 2D AF transition occurred at 15 K.Comment: 12 pages, 14 figures, and 2 table

    Vibrational energy relaxation in proteins

    Full text link
    An overview of theories related to vibrational energy relaxation (VER) in proteins is presented. VER of a selected mode in cytochrome c is studied using two theoretical approaches. One is the equilibrium simulation approach with quantum correction factors, and the other is the reduced model approach which describes the protein as an ensemble of normal modes interacting through nonlinear coupling elements. Both methods result in estimates of the VER time (sub ps) for a CD stretching mode in the protein at room temperature. The theoretical predictions are in accord with the experimental data of Romesberg's group. A perspective on future directions for the detailed study of time scales and mechanisms for VER in proteins is presented.Comment: 12 pages, 4 figures, accepted for publication in PNA

    Urban Diabetic Women\u27s Perception of Healthy Eating Lifestyles From West Java

    Full text link
    This study aimed to explore perceptions about a healthy-eating lifestyle and reasons to practice a healthy-eating lifestyle of women with type 2 diabetes in a city of West Java by using a case study design. Six female patients, with type 2 diabetes, ages 47–63 from a hospital were interviewed guided by the health promotion model. Their healthy-eating lifestyle included currently practicing or not practicing a healthy-eating lifestyle. Reasons to practice were: beliefs for health and for physical energy to work for family, definition of multidimensional health and self-efficacy increased by: support from God, support from family, support from health professionals and improved or deteriorated health status by prior experience. Reasons not to practice were: difficulty in arranging diet, rejecting eating, controlling appetite, and accessing health care services. Related difficulties were interpersonal relations with family and social situation such as social events, expensive medical fee, and distance to the hospital. These findings suggest that women with type 2 diabetes in Indonesia need to be supported with the reasons to practice a healthy-eating lifestyle
    corecore