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Based on Voronoi analysis, the properties related to the near-wall motion of particles in a turbulent boundary layer were experimentally investigated via different release modes, with a friction Reynolds number $Re_\tau =3530$. For high-inertia sand particles with Stokes number $St^+ \sim O(10^2\unicode{x2013}10^3)$ and a volume fraction $\varPhi _v \sim O(10^{-4})$ , particle image tracking velocimetry was used to determine the particle position and near-wall distribution properties. We established three particle release modes, including top-released, bottom overall-released and bottom partially released sand particles, under the same flow field conditions and calculated the differences in particle near-wall clustering and void properties. It was confirmed that wall effects (including collision and strike-splash) have a great influence on particle clustering and void behaviour near the wall. In the top-released sand particle and locally laid sand particle cases, particles bounced off the smooth walls and re-entered the carrier flow, causing significant clustering and sparsing of particles near the walls. In contrast, in the overall sand-laying case where the bottom wall was completely covered with sand particles, there is no apparent cluster or void phenomenon near the wall $(z/\delta and the particles are randomly distributed, due to the combined effect of particle impact and splashing. In addition, the clustering and voids of particles become more pronounced with increasing wall-normal distance in the three release modes, and the particle distribution shows some self-similarity at each flow layer. The probability density function of the concentration of cluster particles decreases following a ' $-5/3$ ' power law. However, due to the particle–wall interaction, the probability density function gradually deviates from the ' $-5/3$ ' power law. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Nutritional risk screening (NRS-2002) and routine clinical laboratory measurements (RCLMs) had been shown to have a predictive value in adverse outcomes in some studies, respectively. This study analyzed the association between NRS-2002 and RCLMs and estimated their prospective value in predicting adverse outcomes. SUBJECTS/METHODS: A total of 916 hospitalized patients were screened on admission with NRS-2002 and Subjective Global Assessment; RCLMs, which include blood test, kidney and liver function and electrolytes, were recorded. Diagnosis, nutritional support, surgery, radiotherapy, chemotherapy, complications, mortality and hospital stay during hospitalization were collected. The [X.sup.2]-test, odds ratios with 95% confidence intervals, kappa (k) statistic and regression analyses were conducted. RESULTS: An overall 48.1% of the 916 patients were at nutritional risk on admission. Comparing 'at risk' with 'no risk', a significantly higher incidence of abnormality was found not only in nutritional markers but also in other parameters of RCLMs (OR ranged from 1.5 to 3.5). Regression analyses showed that 'at risk' determined at admission was not a significant predictor of adverse outcomes after adjusting for other confounding factors, although it was a strong predictor in univariate analysis, whereas hypoalbuminemia, low total lymphocyte count, abnormality of hepatic and renal function were predictors after adjusting for confounders. CONCLUSIONS: The findings suggest that NRS-2002 might be a global index of 'sickness' rather than be only a nutritional screening tool. It being rated once at admission is insufficient and should be repeated for using it as a predictor, whereas RCLMs routinely measured at admission may be able to be used to predict adverse outcomes. European Journal of Clinical Nutrition (2015) 69, 552-557; doi:10.1038/ejcn.2014.239; published online 5 November 2014, INTRODUCTION Although the prefix mal refers to both over and under, because of poor appetite and absorption caused by illness, malnutrition was often mentioned virtually synonymously with undernutrition in hospitals, [...]

This paper presents a magnetoelectric (ME) heterostructure of a magnetostrictive Terfenol-D/epoxy 0-3 composite (MSCP) plate combined with a piezoelectric PZT/epoxy 0-3 composite (PECP) plate along the longitudinal direction. By keeping the dimensions of the MSCP at 6.8 mm x 6.2 mm x 0.7 mm, heterostructures with various PECP lengths of 8-15 mm are prepared and characterized to reveal their frequency dependence of the ME effect. The results exhibit several resonance peaks in the heterostructures due to the magnetomechanical resonances (MMR) of the MSCP and the electromechanical resonances (EMR) of the PECP. The superposition of the MMR and EMR enhances significantly the ME output of the heterostructures. The highest ME voltage coefficient ([[alpha].sub.E]) of 13.1 V/cm. Oe is observed at the resonance frequency of 106.8 kHz when the length ratio of the MSCP and PECP is set to 6.8/10.2, together with an optimal magnetic bias field of 0.7 kOe. Index Terms--Heterostructures, magnetoelectric (ME) composites, magnetostrictive composites, piezoelectric composites.

In this paper, we analyze the melting behavior of zirconium nanowire using the results of a series of molecular dynamics simulations. Our calculation employs a well-fitted, tight-binding many-body potential for zirconium atoms. The melting point of the nanowire is predicted by the root-mean-square displacements for inner and outer shells. Our simulations predict two melting behaviors: one is the inner melting and the other is the outer melting. Our results reveal that the melting of nanowire starts from the inner shell atoms. The melting point of zirconium nanowire is lower than the bulk value (2125 K). Moreover, the melting point of the inner shell is lower than that of the outer shell. A coexistence of crystal and liquid units is observed in the melting process of nanowire. An investigation of local clusters is carried out to further analyze the melting mechanism of the nanowire. The presence of the local clusters 1331, 1321, 1211, etc. is an indication of disordered structures. The pair and angular correlation functions are also presented for the analysis of the melting behavior. It is not only the diffusion of single atom but the diffusion of clusters result in the occurrence of the melting. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigations of the structures of gold nanowires are performed by using genetic algorithm simulation based on the molecular dynamics with a glue potential. Results are reported for some local clusters and defect polyhedra in nanowires. The pair correlation functions and pair analysis technique are used to study the cluster in nanowires. Not only are Frank–Kasper polyhedra and Bernal hole polyhedra detected, but also a variety of defects in nanowires with big diameter. Nanowires with small diameter have a splitting of second peak in PCF and characteristic amorphous features are observed in nanowires with small diameter. The angular correlation functions of gold nanowire have also been studied. Both the favorable energy and the small distortion result in bond pairs having the appropriate population. A suitable proportion of the number of bond pairs is an important factor for the nanowire forming ability. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A magnetoelectric (ME) hybrid structure is constructed by an efficient coupling between magnetostrictive Terfenol-D/Epoxy composite combined with 0-3 Pb(Zr0.52Ti0.48)O3/epoxy composite [piezoelectric component (PECP)]. It is revealed that the ME effect can be enhanced by applying an optimized magnetic bias.