Quantitative Scanning Electron Acoustic Microscopy of Silicon

So far results of scanning electron acoustic microscopy (SEAM) have retained a widely qualitative meaning only due to the enormous uncertainty in understanding sound generation and contrast mechanisms in SEAM micrographs. In this work, a detailed treatment of these mechanisms has been undertaken for silicon resulting in precise knowledge of the signal generation processes and a well understood interpretation of the contrast mechanisms involved in imaging thermo-mechanical and electronic features

Tau Polarization in Λb→Xcτνˉ \Lambda_b \to X_c \tau \bar{\nu} and B→XcτνˉB \to X_c \tau \bar{\nu}

We discuss the longitudinal and transverse $\tau$-polarization in inclusive decays of hadrons containing $b$-quarks. The calculation is performed by means of an OPE in HQET. Some mathematical difficulties in calculating transverse polarizations are explained. Numerical results are presented for longitudinal and for transverse polarizations, both in and perpendicular to the decay plane.Comment: LATEX, 20 pages, 5 Postscript figure

Signal generation mechanisms in scanning-electron acoustic microscopy of ionic crystals

MgO crystals have been studied by scanning‐electron acoustic microscopy under different experimental conditions. Contrast mechanisms in imaging are discussed and compared. The experimental results obtained by earthing or nonearthing the specimen‐transducer interface suggest the existence of a signal generation mechanism that is related to the ionic nature of these kind of crystals. Electron‐acoustic microscopy appears then to be a useful tool for the characterization of ionic materials

Measurements of Nanoscale Domain Wall Flexing in a Ferromagnetic Thin Film

We use the high spatial sensitivity of the anomalous Hall effect in the ferromagnetic semiconductor Ga1-xMnxAs, combined with the magneto-optical Kerr effect, to probe the nanoscale elastic flexing behavior of a single magnetic domain wall in a ferromagnetic thin film. Our technique allows position sensitive characterization of the pinning site density, which we estimate to be around 10^14 cm^{-3}. Analysis of single site depinning events and their temperature dependence yields estimates of pinning site forces (10 pN range) as well as the thermal deactivation energy. Finally, our data hints at a much higher intrinsic domain wall mobility for flexing than previously observed in optically-probed micron scale measurements

Imaging of Local Thermal and Electrical Conductivity with Scanning Force Microscopy

The evaluation of thermal and electrical properties has been demonstrated using a scanning force microscope under ambient air condition. For the first time, the investigation of thermal conductivity on a chemical vapor deposited (CVD) grown diamond surface has been performed with a lateral resolution below 200 nm. Depending on the growing parameters, structures consisting of lines of different thicknesses and spacings are visible. The determination of the electrical structure has been carried out with a resolution of 2 nm using the contact current mode (CCM) showing similar structures. The thermal images exhibit a high thermal conductivity mostly on the diamond crystals whereas the electrical conductivity reached its highest values between them

Action minimizing fronts in general FPU-type chains

We study atomic chains with nonlinear nearest neighbour interactions and prove the existence of fronts (heteroclinic travelling waves with constant asymptotic states). Generalizing recent results of Herrmann and Rademacher we allow for non-convex interaction potentials and find fronts with non-monotone profile. These fronts minimize an action integral and can only exists if the asymptotic states fulfil the macroscopic constraints and if the interaction potential satisfies a geometric graph condition. Finally, we illustrate our findings by numerical simulations.Comment: 19 pages, several figure

Evaluation of person-level heterogeneity of treatment effects in published multiperson N-of-1 studies: systematic review and reanalysis.

OBJECTIVE:Individual patients with the same condition may respond differently to similar treatments. Our aim is to summarise the reporting of person-level heterogeneity of treatment effects (HTE) in multiperson N-of-1 studies and to examine the evidence for person-level HTE through reanalysis. STUDY DESIGN:Systematic review and reanalysis of multiperson N-of-1 studies. DATA SOURCES:Medline, Cochrane Controlled Trials, EMBASE, Web of Science and review of references through August 2017 for N-of-1 studies published in English. STUDY SELECTION:N-of-1 studies of pharmacological interventions with at least two subjects. DATA SYNTHESIS:Citation screening and data extractions were performed in duplicate. We performed statistical reanalysis testing for person-level HTE on all studies presenting person-level data. RESULTS:We identified 62 multiperson N-of-1 studies with at least two subjects. Statistical tests examining HTE were described in only 13 (21%), of which only two (3%) tested person-level HTE. Only 25 studies (40%) provided person-level data sufficient to reanalyse person-level HTE. Reanalysis using a fixed effect linear model identified statistically significant person-level HTE in 8 of the 13 studies (62%) reporting person-level treatment effects and in 8 of the 14 studies (57%) reporting person-level outcomes. CONCLUSIONS:Our analysis suggests that person-level HTE is common and often substantial. Reviewed studies had incomplete information on person-level treatment effects and their variation. Improved assessment and reporting of person-level treatment effects in multiperson N-of-1 studies are needed

Scanning electron‐acoustic microscopy of MgO crystals

The capability of scanning electron‐acoustic microscopy in the characterization of MgO crystals has been studied. The conditions for the observation of different surface and subsurface features in as‐grown and deformed crystals are described and the results are discussed on the basis of thermal and nonthermal mechanisms of acoustic signalgeneration

An evaluation of cross-efficiency methods: With an application to warehouse performance

Cross-efficiency measurement is an extension of Data Envelopment Analysis that allows for tie-breaking ranking of the Decision Making Units (DMUs) using all the peer evaluations. In this article we examine the theory of cross-efficiency measurement by comparing a selection of methods popular in the literature. These methods are applied to performance measurement of European warehouses. We develop a cross-efficiency method based on a rank-order DEA model to accommodate the ordinal nature of some key variables characterizing warehouse performance. This is one of the first comparisons of methods on a real-life dataset and the first time that a model allowing for qualitative variables is included in such a comparison. Our results show that the choice of model matters, as one obtains statistically different rankings from each one of them. This holds in particular for the multiplicative and game-theoretic methods whose results diverge from the classic method. From a managerial perspective, focused on the applicability of the methods, we evaluate them through a multidimensional metric which considers their capability to rank DMUs, their ease of implementation, and their robustness to sensitivity analyses. We conclude that standard weight-restriction methods, as initiated by Sexton et al. [48], perform as well as recently introduced, more sophisticated alternativesSpanish Ministry of Science and Innovation (Ministerio de Ciencia e Innovación), the State Research Agency (Agencia Estatal de Investigación) and the European Regional Development Fund (Fondo Europeo de Desarrollo Regional) under grants EIN2020-11226