Ray theory for high-Péclet-number convection-diffusion

Asymptotic methods based on those of geometrical optics are applied to some steady convection-diffusion streamed flows at a high Péclet number. Even with the assumption of inviscid, irrotational flow past a body with uniform ambient conditions, the rays from which the solution is constructed can only be found after local analyses have been carried out near the stagnation points. In simple cases, the temperature away from the body is the sum of contributions from each stagnation point

On the theory of complex rays

The article surveys the application of complex-ray theory to the scalar Helmholtz equation in two dimensions. The first objective is to motivate a framework within which complex rays may be used to make predictions about wavefields in a wide variety of geometrical configurations. A crucial ingredient in this framework is the role played by Sp{} in determining the regions of existence of complex rays. The identification of the Stokes surfaces emerges as a key step in the approximation procedure, and this leads to the consideration of the many characterizations of Stokes surfaces, including the adaptation and application of recent developments in exponential asymptotics to the complex Wentzel--Kramers--Brilbuin expansion of these wavefields

Cross-Education Balance Effects After Unilateral Rehabilitation in Individuals With Chronic Ankle Instability: A Systematic Review

Objective: To conduct a systematic review of existing literature on cross-education balance effects after unilateral training in the population with chronic ankle instability (CAI). Data Sources: PubMed, SPORTDiscus, CINAHL Plus. Study Selection: To be included in the systematic review, studies were required to have been published in English, included participants with CAI, had participants undergo a unilateral therapeutic exercise for the lower extremity, and measured balance performance of the untrained lower extremity before and after the intervention. Data Extraction: The certainty of evidence in each included study was assessed via the Downs and Black checklist. A score of 24 to 28 indicated excellent or very low risk of bias; 19 to 23, good or low risk of bias; 14 to 18, fair or moderate risk of bias; and poor or high risk of bias. We extracted information from each study regarding design, participant characteristics, inclusion criteria, independent and dependent variables, intervention, and results. Baseline and postintervention balance performance data for participants\u27 untrained limbs were used to calculate the Hedges g effect sizes and 95% CIs. Data Synthesis: Our search returned 6 studies that met the inclusion criteria. The articles\u27 risk of bias ranged from high to low (11–19). In 4 of 5 studies that examined unilateral balance training, the authors reported a cross-education effect. In the lone study that examined resistance training at the ankle joint, a cross-education effect was also present. Several cross-education effects were associated with large effect sizes. This systematic review was limited by a small number of studies that varied in methods and quality. Conclusions: Our results suggest that unilateral therapeutic exercise can improve balance performance of the untrained limb of individuals with CAI. More work is needed to determine which training protocols are most effective for generating a cross-education effect

Mobile radio propagation prediction using ray tracing methods

The basic problem is to solve the two-dimensional scalar Helmholtz equation for a point source (the antenna) situated in the vicinity of an array of scatterers (such as the houses and any other relevant objects in 1 square km of urban environment). The wavelength is a few centimeters and the houses a few metres across, so there are three disparate length scales in the problem. The question posed by BT concerned ray counting on the assumptions that: (i) rays were subject to a reflection coefficient of about 0.5 when bouncing off a house wall and (ii) that diffraction at corners reduced their energy by 90%. The quantity of particular interest was the number of rays that need to be accounted for at any particular point in order for those neglected to only contribute 10% of the field at that point; a secondary question concerned the use of rays to predict regions where the field was less than 1% of that in the region directly illuminated by the antenna. The progress made in answering these two questions is described in the next two sections and possibly useful representations of the solution of the Helmholtz equations in terms other than rays are given in the final section

Phenylpyrrole fungicides act on triosephosphate isomerase to induce methylglyoxal stress and alter hybrid histidine kinase activity.

Fludioxonil, a natural product of pyrrolnitrin, is a potent fungicide used on crops worldwide. Drug action requires the presence of a group III hybrid histidine kinase (HHK) and the high osmolarity glycerol (HOG) pathway. We have reported that the drug does not act directly on HHK, but triggers the conversion of the kinase to a phosphatase, which dephosphorylates Ypd1 to constitutively activate HOG signaling. Still, the direct drug target remains unknown and mode of action ill defined. Here, we heterologously expressed a group III HHK, dimorphism-regulating kinase 1 (Drk1) in Saccharomyces cerevisae to delineate fludioxonil's target and action. We show that the drug interferes with triosephosphate isomerase (TPI) causing release of methylglyoxal (MG). MG activates the group III HHK and thus the HOG pathway. Drug action involved Drk1 cysteine 392, as a C392S substitution increased drug resistance in vivo. Drug sensitivity was reversed by dimedone treatment, indicating Drk1 responds in vivo to an aldehydic stress. Fludioxonil treatment triggered elevated cytosolic methylglyoxal. Likewise, methylglyoxal treatment of Drk1-expressing yeast phenocopied treatment with fludioxonil. Fludioxonil directly inhibited TPI and also caused it to release methylglyoxal in vitro. Thus, TPI is a drug target of the phenylpyrrole class of fungicides, inducing elevated MG which alters HHK activity, likely converting the kinase to a phosphatase that acts on Ypd1 to trigger HOG pathway activation and fungal cell death

Complete fuzzy scheduling and fuzzy earned value management in construction projects

Complete fuzzy scheduling and fuzzy earned value management in construction projects Por: Luis Ponz-Tienda, Jose; Pellicer, Eugenio; Yepes, Victor JOURNAL OF ZHEJIANG UNIVERSITY-SCIENCE A Volumen: 13 Número: 1 Páginas: 56-68 Fecha de publicación: JAN 2012 Search For Full Text Cerrar abstractCerrar abstract This paper aims to present a comprehensive proposal for project scheduling and control by applying fuzzy earned value. It goes a step further than the existing literature: in the formulation of the fuzzy earned value we consider not only its duration, but also cost and production, and alternatives in the scheduling between the earliest and latest times. The mathematical model is implemented in a prototypical construction project with all the estimated values taken as fuzzy numbers. Our findings suggest that different possible schedules and the fuzzy arithmetic provide more objective results in uncertain environments than the traditional methodology. The proposed model allows for controlling the vagueness of the environment through the adjustment of the alpha-cut, adapting it to the specific circumstances of the project. © Zhejiang University and Springer-Verlag Berlin Heidelberg 2012.The authors want to thank Ms. Doria GIL-SENABRE, Universitat Politecnica de Valencia, Spain, for the support provided.Ponz Tienda, JL.; Pellicer Armiñana, E.; Yepes Piqueras, V. (2012). Complete fuzzy scheduling and fuzzy earned value management in construction projects. Journal of Zhejiang University Science A. 13(1):56-68. https://doi.org/10.1631/jzus.A1100160S566813