Chaotic Properties of Dilute Two and Three Dimensional Random Lorentz Gases II: Open Systems

We calculate the spectrum of Lyapunov exponents for a point particle moving in a random array of fixed hard disk or hard sphere scatterers, i.e. the disordered Lorentz gas, in a generic nonequilibrium situation. In a large system which is finite in at least some directions, and with absorbing boundary conditions, the moving particle escapes the system with probability one. However, there is a set of zero Lebesgue measure of initial phase points for the moving particle, such that escape never occurs. Typically, this set of points forms a fractal repeller, and the Lyapunov spectrum is calculated here for trajectories on this repeller. For this calculation, we need the solution of the recently introduced extended Boltzmann equation for the nonequilibrium distribution of the radius of curvature matrix and the solution of the standard Boltzmann equation. The escape-rate formalism then gives an explicit result for the Kolmogorov Sinai entropy on the repeller.Comment: submitted to Phys Rev

Ralgro-implanted bulls: Performance, carcass characteristics, longissimus palatability and carcass electrical stimulation

Twenty of 40 Angus bulls were implanted (I) five times with 36 mg of Ralgro| at average intervals of 106 d, beginning near birth. All bulls and their dams were on bluestem pasture initially and, at an average age of 320 d bulls were fed a concentrate diet until they were slaughtered, weighing either 454 or 499 kg. One side of each carcass was electrically stimulated. Average daily gain and feed efficiency of I bulls improved 6.5 to 10.4% and 7.9 to 8.1%, respectively, depending upon the end point comparison with nonimplanted (NI) bulls. Implanted bulls attained their slaughter weights 42 d sooner than did NI bulls. Implantation decreased (P<.05) penis weight and length, testicle weight, volume and density, but did not affect (P>.05) seminal vesicle and pituitary weights. Carcasses from I bulls had more (P<.05) skeletal ossification and were fatter than carcasses from NI bulls. Marbling scores, quality grades and longissimus cooking losses and juiciness scores were not affected (P>.05) by implantation. Taste panel flavor intensity and detectable connective tissue scores were higher (P<.05) for steaks from I bulls than from NI bulls. Longissimus steak tenderness evaluations were higher (P<.05) for both I slaughter groups than for the NI light-weight group and were higher (P<.05) for the I lightweight group than for the NI heavy-weight group. Longissimus tenderness tended (P = .11) to be higher for steaks from the I heavy-weight group than those from the NI heavy-weight group. Electrical stimulation produced (P<.05) a softer, coarser textured lean, but it did not affect lean color, marbling or quality grade. Steaks from electrically stimulated sides tended to have higher (P = .09) myofibrillar tenderness scores and lower (P = .06) flavor scores than steaks from nonstimulated sides

Dispersion of Ordered Stripe Phases in the Cuprates

A phase separation model is presented for the stripe phase of the cuprates, which allows the doping dependence of the photoemission spectra to be calculated. The idealized limit of a well-ordered array of magnetic and charged stripes is analyzed, including effects of long-range Coulomb repulsion. Remarkably, down to the limit of two-cell wide stripes, the dispersion can be interpreted as essentially a superposition of the two end-phase dispersions, with superposed minigaps associated with the lattice periodicity. The largest minigap falls near the Fermi level; it can be enhanced by proximity to a (bulk) Van Hove singularity. The calculated spectra are dominated by two features -- this charge stripe minigap plus the magnetic stripe Hubbard gap. There is a strong correlation between these two features and the experimental photoemission results of a two-peak dispersion in La$_{2-x}$Sr$_x$CuO$_4$, and the peak-dip-hump spectra in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. The differences are suggestive of the role of increasing stripe fluctuations. The 1/8 anomaly is associated with a quantum critical point, here expressed as a percolation-like crossover. A model is proposed for the limiting minority magnetic phase as an isolated two-leg ladder.Comment: 24 pages, 26 PS figure

The Intentional Use of Service Recovery Strategies to Influence Consumer Emotion, Cognition and Behaviour

Service recovery strategies have been identified as a critical factor in the success of. service organizations. This study develops a conceptual frame work to investigate how specific service recovery strategies influence the emotional, cognitive and negative behavioural responses of . consumers., as well as how emotion and cognition influence negative behavior. Understanding the impact of specific service recovery strategies will allow service providers' to more deliberately and intentionally engage in strategies that result in positive organizational outcomes. This study was conducted using a 2 x 2 between-subjects quasi-experimental design. The results suggest that service recovery has a significant impact on emotion, cognition and negative behavior. Similarly, satisfaction, negative emotion and positive emotion all influence negative behavior but distributive justice has no effect

Coeliac disease-associated risk variants in TNFAIP3 and REL implicate altered NF-kappaB signalling

Objective: Our previous coeliac disease genome-wide association study (GWAS) implicated risk variants in the human leucocyte antigen (HLA) region and eight novel risk regions. To identify more coeliac disease loci, we selected 458 single nucleotide polymorphisms (SNPs) that showed more modest association in the GWAS for genotyping and analysis in four independent cohorts. Design: 458 SNPs were assayed in 1682 cases and 3258 controls from three populations (UK, Irish and Dutch). We combined the results with the original GWAS cohort (767 UK cases and 1422 controls); six SNPs showed association with p Results: We identified two novel coeliac disease risk regions: 6q23.3 (OLIG3-TNFAIP3) and 2p16.1 (REL), both of which reached genome-wide significance in the combined analysis of all 2987 cases and 5273 controls (rs2327832 p= 1.3x10(-08), and rs842647 p= 5.26x10(-07)). We investigated the expression of these genes in the RNA isolated from biopsies and from whole blood RNA. We did not observe any changes in gene expression, nor in the correlation of genotype with gene expression. Conclusions: Both TNFAIP3 (A20, at the protein level) and REL are key mediators in the nuclear factor kappa B (NF-kappa B) inflammatory signalling pathway. For the first time, a role for primary heritable variation in this important biological pathway predisposing to coeliac disease has been identified. Currently, the HLA risk factors and the 10 established non-HLA risk factors explain similar to 40% of the heritability of coeliac disease

Defects and glassy dynamics in solid He-4: Perspectives and current status

We review the anomalous behavior of solid He-4 at low temperatures with particular attention to the role of structural defects present in solid. The discussion centers around the possible role of two level systems and structural glassy components for inducing the observed anomalies. We propose that the origin of glassy behavior is due to the dynamics of defects like dislocations formed in He-4. Within the developed framework of glassy components in a solid, we give a summary of the results and predictions for the effects that cover the mechanical, thermodynamic, viscoelastic, and electro-elastic contributions of the glassy response of solid He-4. Our proposed glass model for solid He-4 has several implications: (1) The anomalous properties of He-4 can be accounted for by allowing defects to freeze out at lowest temperatures. The dynamics of solid He-4 is governed by glasslike (glassy) relaxation processes and the distribution of relaxation times varies significantly between different torsional oscillator, shear modulus, and dielectric function experiments. (2) Any defect freeze-out will be accompanied by thermodynamic signatures consistent with entropy contributions from defects. It follows that such entropy contribution is much smaller than the required superfluid fraction, yet it is sufficient to account for excess entropy at lowest temperatures. (3) We predict a Cole-Cole type relation between the real and imaginary part of the response functions for rotational and planar shear that is occurring due to the dynamics of defects. Similar results apply for other response functions. (4) Using the framework of glassy dynamics, we predict low-frequency yet to be measured electro-elastic features in defect rich He-4 crystals. These predictions allow one to directly test the ideas and very presence of glassy contributions in He-4.Comment: 33 pages, 13 figure

Can natural flavorings enhance the flavor of low-fat ground beef?

Natural flavorings were evaluated for use in low-fat ground beef, which frequently lacks flavor intensity. Three lean sources, A-maturity (young), E-maturity (mature cow), and imported (cow) beef round muscles, were used to formulate 7% and 25% fat ground beef. A-maturity fat was added to adjust fat levels. Controls (no added flavors) were prepared for each lean source. No additives were used in 25% fat controls, but 7% fat controls contained water (10%), carrageenan (.5%), and encapsulated salt (.38%). Four natural flavorings; Dried Cream Extract (DCE, Cumberland Packing Co., Inc.); Natural Prime Beef Base WONF #224545 and #224546 (224545, 224546, Tastemaker); and Hydrolyzed Vegetable Protein (HVP, A.C. Legg, Inc.) were added to 7% fat ground beef at recommended levels. A- and E-maturity domestic 25% fat controls were scored higher (P\u3c.05) for ground beef flavor intensity and lower (P\u3c.05) for off-flavors than 25% fat patties from imported beef. The 7% fat patties from imported lean had greater (P\u3c.05) beef flavor intensity and reduced off-flavors (P\u3c.05) when flavorings 224545, 224546, and HVP were added. These flavorings also enhanced the beef flavor intensity of low-fat patties from A-maturity lean to a level similar to that of the 25% fat control. Beef flavor intensity after a 60-min holding period was not enhanced by the natural flavorings, except when 224546 was added to E-maturity domestic lean. Therefore, the natural flavorings were most beneficial with imported lean

Customer emotions in service failure and recovery encounters

Emotions play a significant role in the workplace, and considerable attention has been given to the study of employee emotions. Customers also play a central function in organizations, but much less is known about customer emotions. This chapter reviews the growing literature on customer emotions in employee–customer interfaces with a focus on service failure and recovery encounters, where emotions are heightened. It highlights emerging themes and key findings, addresses the measurement, modeling, and management of customer emotions, and identifies future research streams. Attention is given to emotional contagion, relationships between affective and cognitive processes, customer anger, customer rage, and individual differences

The uses and abuses of power: teaching school leadership through children's literature

There are relatively few studies of how representations of teachers, schools and educational administrators in popular films and television might be, and are, used in leadership preparation. This paper seeks to add to this small body of work; it reports on an exploratory study of the representation of headteachers in contemporary children's fiction. Thirty-one texts are analysed to ascertain key themes and the major characterisations. The paper draws on children's literature scholars to argue that both the historical school story and its contemporary counterpart focus heavily on the power of the head to control the micro-world of the school. Because these fictional accounts deal with issues of power and justice more openly than many mainstream educational administration texts, this makes them particularly useful in the preparation of potential school leaders

History of clinical transplantation

How transplantation came to be a clinical discipline can be pieced together by perusing two volumes of reminiscences collected by Paul I. Terasaki in 1991-1992 from many of the persons who were directly involved. One volume was devoted to the discovery of the major histocompatibility complex (MHC), with particular reference to the human leukocyte antigens (HLAs) that are widely used today for tissue matching.1 The other focused on milestones in the development of clinical transplantation.2 All the contributions described in both volumes can be traced back in one way or other to the demonstration in the mid-1940s by Peter Brian Medawar that the rejection of allografts is an immunological phenomenon.3,4 © 2008 Springer New York