There is no MacWilliams identity for convolutional codes

An example is provided of two convolutional codes that have the same transmission gain but whose dual codes do not. This shows that no analog of the MacWilliams identity for block codes can exist relating the transmission gains of a convolutional code and its dual

Lower bounds for small diagonal ramsey numbers

AbstractLet p = 4r + 1 be a prime. Let G be the graph on the p points 0, 1,…, p−1 formed by connecting two points with an edge iff their difference is a quadratic residue mod p. Let k be the size of the largest clique contained in G. Then it is well known that the diagonal Ramsey number R2(k + 1) > p. We show R2(k + 2) > 2p + 2. We also compute k for all p < 3000

Canker disease in Corymbia calophylla (Marri) in the south west of Western Australia

Cankering of marri in the southern forests of Western Australia is causing concern as it is increasing considerably in severity and geographic range. The contribution of canker fungi to stem, branch and tree death has not been studied in detail, and the causal agent(s) is yet to be determined (1). This project examined disease incidence and associated pathogens

Stabilized lanthanum sulphur compounds

Lanthanum sulfide is maintained in the stable cubic phase form over a temperature range of from 500 C to 1500 C by adding to it small amounts of calcium, barium, or strontium. This compound is an excellent thermoelectric material

A comparison of the in vitro and in planta responses of Phytophthora cinnamomi isolates to phosphite

Research in plant pathology often relies on testing interactions between a fungicide and a pathogen in vitro and extrapolating from these results what may happen in planta. Likewise, results from glasshouse experiments are used to estimate what will happen if the fungicide is applied in the field. However, it is difficult to obtain conditions in vitro and in the glasshouse which reflect the conditions where the fungicide may eventually be used, in the field. The aim of this paper is to compare results of the effect of phosphite on P. cinnamomi isolates in vitro and in planta

Critical Practice Study of Nursing Evaluated by Teachers

Purpose:&nbsp;Competent nursing care is essential to positive patient outcomes and quality patient care. Graduate nurses begin practice as novices in knowledge and experience often entering an environment where patients have several disease processes complicating their care. A strong foundation of educational competencies prior to entering practice is vital for the development and growth of graduate nurses into the role of RN. The purpose of this study was to examine the use of the Nurse Competence Scale among nursing faculty.Method:&nbsp;Nursing faculty were surveyed to determine which competencies were a priority in nursing practice. The Nurse Competence Scale was used to identify and categorize nurse competences. Brenner’s novice to expert theoretical framework was used to apply findings to curricular programs. IRB approval was granted from each educational institution. SPSS statistical analysis was used to analyze survey results.Results:&nbsp;Among the categories of the Nurse Competence Scale, nursing faculty identified Acting appropriately in life-threatening situations in the Managing Situations section as most important to practice. In the category of Helping, Planning patient care according to individual needs was identified as most important. Additionally the nursing faculty surveyed rated Contributing to further development of multidisciplinary clinical paths in the Therapeutic Interventions category as the lowest.Conclusion:&nbsp;This study contributes to the discussion on nursing competence. Priorities for nursing faculty aligned with register nurses in practice. This study helps pair nursing education with practice in several ways including aligning current practice with education. Nurse Educators may use these findings to help join curricular outcomes with practice. Evaluating each item on the Nurse Competence Scale using the critical to practice scale provides insight to the necessary skills and knowledge needed to be competent in nursing. In addition the results may be compared to current practice guidelines to ensure best practice. Further research linking education and practice using nursing competence is needed

Shear-driven size segregation of granular materials: modeling and experiment

Granular materials segregate by size under shear, and the ability to quantitatively predict the time required to achieve complete segregation is a key test of our understanding of the segregation process. In this paper, we apply the Gray-Thornton model of segregation (developed for linear shear profiles) to a granular flow with an exponential profile, and evaluate its ability to describe the observed segregation dynamics. Our experiment is conducted in an annular Couette cell with a moving lower boundary. The granular material is initially prepared in an unstable configuration with a layer of small particles above a layer of large particles. Under shear, the sample mixes and then re-segregates so that the large particles are located in the top half of the system in the final state. During this segregation process, we measure the velocity profile and use the resulting exponential fit as input parameters to the model. To make a direct comparison between the continuum model and the observed segregation dynamics, we locally map the measured height of the experimental sample (which indicates the degree of segregation) to the local packing density. We observe that the model successfully captures the presence of a fast mixing process and relatively slower re-segregation process, but the model predicts a finite re-segregation time, while in the experiment re-segregation occurs only exponentially in time

Segregation by thermal diffusion in granular shear flows

Segregation by thermal diffusion of an intruder immersed in a sheared granular gas is analyzed from the (inelastic) Boltzmann equation. Segregation is induced by the presence of a temperature gradient orthogonal to the shear flow plane and parallel to gravity. We show that, like in analogous systems without shear, the segregation criterion yields a transition between upwards segregation and downwards segregation. The form of the phase diagrams is illustrated in detail showing that they depend sensitively on the value of gravity relative to the thermal gradient. Two specific situations are considered: i) absence of gravity, and ii) homogeneous temperature. We find that both mechanisms (upwards and downwards segregation) are stronger and more clearly separated when compared with segregation criteria in systems without shear.Comment: 8 figures. To appear in J. Stat. Mec