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We determine the zero and finite temperature phase diagram of the fully frustrated quantum Ising model on the bathroom tile (4-8) lattice. The phase diagram exhibits a wealth of 2+1d physics, including 1. classical Coulomb dimer liquids of both square and triangular lattice types; 2. quantum order-by-disorder induced phases breaking $\mathbb{Z}_4$, $\mathbb{Z}_6$, and $\mathbb{Z}_8$ symmetries; 3. finite temperature Kosterlitz-Thouless (KT) phases floating over the $\mathbb{Z}_6$ and $\mathbb{Z}_8$ orders; and, 4. staircases of (in)-commensurate symmetry breaking phases at intermediate coupling. We establish this elaborate phase diagram using a combination of dimer model mapping, perturbation theory, Landau analysis and Stochastic Series Expansion Quantum Monte Carlo (QMC-SSE). Our results provide a baseline for studying frustrated magnetism with D-Wave architecture annealers, where the 4-8 lattice can be embedded naturally without `cloning', reducing the number of competing energy scales. Simulations with the D-Wave 2000Q demonstrate qualitative agreement with the high temperature portion of the phase diagram, but are unable to access the low temperature phases., Comment: 14 pages, 20 figures

In the School of Health Sciences we have adopted a blended learning approach for the delivery of the current nursing curriculum. It is intended to enhance and extend the learning opportunities for students.\ud \ud This approach makes full use of available learning technologies whilst recognising the value of face to face interaction and facilitation. It fosters supportive and collaborative learning networks amongst students and encourages deep learning by engaging students in incremental learning tasks and, student directed learning. It also enables students to self- pace their learning.\ud \ud As our nursing programme is being implemented we have engaged both academics and students in a systematic and iterative evaluation of the blended aspects of the programme.\ud \ud Our aims were to:\ud a) Investigate how students experience the current balance between their classroom and online activities\ud b) Evaluate the effectiveness of the range of activities, both online and face to face\ud c) Identify points of good practice based on project evaluation and available literature.\ud \ud In this paper we share the results of our evaluation and highlight key messages for further development and improvement of designing the ‘blend’. Our recommendations may be beneficial for design teams who may need to engage in similar projects in the future.

Multidimensional data distributions can have complex topologies and variable local dimensions. To approximate complex data, we propose a new type of low-dimensional ``principal object'': a principal cubic complex. This complex is a generalization of linear and non-linear principal manifolds and includes them as a particular case. To construct such an object, we combine a method of topological grammars with the minimization of an elastic energy defined for its embedment into multidimensional data space. The whole complex is presented as a system of nodes and springs and as a product of one-dimensional continua (represented by graphs), and the grammars describe how these continua transform during the process of optimal complex construction. The simplest case of a topological grammar (``add a node'', ``bisect an edge'') is equivalent to the construction of ``principal trees'', an object useful in many practical applications. We demonstrate how it can be applied to the analysis of bacterial genomes and for visualization of cDNA microarray data using the ``metro map'' representation. The preprint is supplemented by animation: ``How the topological grammar constructs branching principal components (AnimatedBranchingPCA.gif)''., Comment: 19 pages, 8 figures

An attempt is made to combine the best features of two materials by forming a heterojunction consisting of a thin film of polycrystalline n-type TiO/sub 2/ deposited on n-type polycrystalline Fe/sub 2/O/sub 3/. Evidence is presented that, under illumination, holes generated in the Fe/sub 2/O/sub 3/ participate in the water decomposition reaction. That is, incident light (2.2

Expressions are given relating municipal bond coupon rates to underwrite profit margins and the market yield. These expressions are applied to the examination of net interest rates, net present value and the cost of capital of serial bond issues. The conditions which must be satisfied so that a decrease in net interest rate corresponds to an increase in net present value (hence a decrease in the cost of capital to the issuer) are presented.

Previous investigation implicated surface charge and surface energy as factors which affect blood clotting. The present paper attempts to explore the theoretical basis for these affects. Expressions are also derived relating change and interfacial tension to the binding constants of the protein. Finally, the possibility of phase transition of the adsorbed protein is discussed and techniques for detecting such changes from adsorption measurements are presented.

A detailed deterministic model for the kinetics of protein synthesis is developed on the assumption that the kinetics of the system depends linearly on the messenger RNA concentration. While the concentration of such components as adaptor RNA and ribosomes are regarded as constant, the messenger RNA input is taken to be time dependent and the analysis is given for both step and ramp inputs. It is shown that the theory predicts a nonlinear build-up in protein concentration followed by a linear phase in agreement with some experimental results. The slope of the linear portion corresponds to the rate of messenger RNA production.

A design theory is developed for a compact artificial kidney utilizing microcapsules containing urease, ion exchange resin, and adsorbents for uric acid and creatinine. It is shown that the critical factor is the permeability property of the microcapsule wall and that an artificial kidney 10 cm in length and 2 cm in diameter is feasible.

The condition for the inverse piezoelectric effect in polymers is discussed and a thermodynamic criteria is derived. The resulting expression is related to the electrical configuration of the polymer and several promising structures are proposed. A dynamical model of the piezoelectric effect is given, and expressions are derived for the compliance and electromechanical losses.

Congenital tricuspid atresia is a complex congenital malformation manifested in a variety of forms. As Edwards and Burchell (8) point out, certain features are common to all cases: (1) atresia of the tricuspid valve, (2) atrial septal defect, (3) a large mitral orifice, and (4) hypoplasia of the right ventricle. Thus the venous return from the systemic circulation flows from the right auricle via the atrial septal defect to the left auricle, where it mixes with arterialized blood entering the left atrium through the pulmonary veins. It then enters the left ventricle, which functions as a single ventricle. Since the left ventricle expels blood into both the pulmonary artery and the aorta, cases of tricuspid atresia may be further subdivided according to the manner in which the blood is distributed through them to the two circulations. The traditional criteria for this subdivision have been the absence or presence of transposition of the great vessels and/or pulmonic stenosis. Thus, in Group I-a of Edwards ...

The properties of the three main classes of orthopedic alloys (316L steel, Co-Cr alloys and titanium) are discussed, while all show good general corrosion resistance, the 316L steel have a tendency toward crevice corrosion. Fatigue fracture due to poor design and fabrication defects is discussed. A summary of some problems associated with the evaluation of tissue response is presented. Finally, a review of several new trends toward achieving tissue adhesion is presented.

A systems analysis is presented directed toward the relating of manpower needs at various educational levels to the overall growth of the educational plant. The resulting formulation encorporates features which are relevant to the situation in the underdeveloped areas. Employment criteria for evaluating the effectiveness of various policies are derived. The resulting algorithm is adaptable to computer programming.

A theory for the behavior of anodes as stimulus electrodes, particularly as pacemaker electrodes, is presented. Expressions are obtained for the minimum duration and energy of the stimulus. These expressions are applied to that for the dissolution of the anode and transport of the resulting ions in the tissue in order to obtain an estimate of the extent of penetration. Comparison with experimental data indicates good agreement.

RELAXIN was first discovered in the blood serum of pregnant rabbits by Hisaw (1926). Subsequent work showed that the relaxative hormone was also present in the blood serum of several species of mammals during pregnancy (Hisaw, 1929; Pommerenke, 1934; Abramson, Hurwitt and Lesnick, 1937). However, the greatest concentration of the hormone was found in the blood of pregnant rabbits (Hisaw, 1929). In this animal relaxin could be detected first on the 7th or 8th day of pregnancy. With the advance of pregnancy increasing amounts of the hormone could be found until a maximal concentration was reached in the latter part of gestation. Qualitative tests of the blood immediately after parturition showed a rapid decline in the hormonal content and about 24 hours after parturition, tests for the hormone were negative. The purpose of the present study was to investigate in a more precise and quantitative way the relationship between the stage of gestation and the concentration of relaxin in the serum and urine of preg...

Etude du vieillissement d'anodes en TiO 2 relativement fortement dopees dans l'obscurite exposees a une solution a 0,1 N de NaOH pendant des durees superieures a 100 heures

Enzyme amplifier systems have been implicated in such diverse physiological phenomena as vision and blood coagulation. Such systems are considered from a general point of view and the concept of steady state gain of the enzyme amplifier is introduced. Expressions for the latter are obtained, and several of the main factors influencing gain are discussed. The effect of the duration of the activation on the characteristics of the response is discussed, and the influence of small changes in the rate constants on the steady state gain is considered.

The present paper describes a simple mathematical model for neighborhoods under-going a racial transition. It is shown that such neighborhoods can be described by 2 parameters which take into account a wide diversity of situations.

The present study provides several simple mathematical expressions which interrelate many of the more important factors associated with the planning of growth of educational facilities. The factors considered include rate of economic development, attrition in graduates available to the labor market due to dropouts, continuation of education, and those'entering the teaching profession. The rate of growth is discussed in terms of the use of teaching devices, on the job training, and the availability of supporting facilities. A linear and exponential phase of growth is recognized.

At the present time, pulmonic stenosis is the most important single criterion in the evaluation of patients with cyanotic congenital malformations of the heart for the selection of those who may benefit from surgical measures. Furthermore, the accurate delineation of the infundibular portion of the right ventricle by angiocardiographic study may be of value in determining whether an aorticopulmonary anastomosis (1, 2) or an infundibular resection be undertaken (3). Dotter and Steinberg (4) have recently estimated that pulmonic stenosis is directly visualized in only one-half the cases of the tetralogy of Fallot. Cooley and his coworkers (5) have also reported that in many of these cases angiocardiography has provided only indirect evidence of pulmonic stenosis. With the development of biplane serial angiocardiography, which allows simultaneous right-angle exposures, greater precision and flexibility have been introduced into this procedure (6). While the number of cases examined by this technic has been s...

The present report provides a detailed systems analysis of the kidney and the associated electrolyte regulatory mechanism, which will be referred to, for purposes of brevity, as the renal chemostat. The model explicitly incorporates the effect of water and salt intake, pulmonary CO2 tension, as well as the main features of renal physiology as it is presently understood. Thus the regulatory function of both aldosterone and antidiuretic hormone are included as well as the effect of such parameters as pH, salt concentration, plasma volume and osmotic factors. The present work thus provides a basis for the development of an electronic analog of the renal-electrolyte system.