Formation of Nanotwin Networks during High-Temperature Crystallization of Amorphous Germanium

Germanium is an extremely important material used for numerous functional applications in many fields of nanotechnology. In this paper, we study the crystallization of amorphous Ge using atomistic simulations of critical nano-metric nuclei at high temperatures. We find that crystallization occurs by the recurrent transfer of atoms via a diffusive process from the amorphous phase into suitably-oriented crystalline layers. We accompany our simulations with a comprehensive thermodynamic and kinetic analysis of the growth process, which explains the energy balance and the interfacial growth velocities governing grain growth. For the $\langle111\rangle$ crystallographic orientation, we find a degenerate atomic rearrangement process, with two zero-energy modes corresponding to a perfect crystalline structure and the formation of a $\Sigma3$ twin boundary. Continued growth in this direction results in the development a twin network, in contrast with all other growth orientations, where the crystal grows defect-free. This particular mechanism of crystallization from amorphous phases is also observed during solid-phase epitaxial growth of $\langle111\rangle$ semiconductor crystals, where growth is restrained to one dimension. We calculate the equivalent X-ray diffraction pattern of the obtained nanotwin networks, providing grounds for experimental validation

Total correlations as fully additive entanglement monotones

We generalize the strategy presented in Refs. [1, 2], and propose general conditions for a measure of total correlations to be an entanglement monotone using its pure (and mixed) convex-roof extension. In so doing, we derive crucial theorems and propose a concrete candidate for a total correlations measure which is a fully additive entanglement monotone.Comment: 8 pages, 3 figures. Title changed, new result

Enhanced gauge symmetries on elliptic K3

We show that the geometry of K3 surfaces with singularities of type A-D-E contains enough information to reconstruct a copy of the Lie algebra associated to the given Dynkin diagram. We apply this construction to explain the enhancement of symmetry in F and IIA theories compactified on singular K3's.Comment: 9 pages, Late

Simple Records Matching Method for diagnostic and clinical datasets of patient’s records

Several statistical packages, either commercials or open-source, provide many methods for multi-factorial and discriminant analysis; such a software is poorly used by physicians. Appropriate models and tests have to be used pending on the kind of experiment scheme, adequate distribution assumption are needed for variables and parameters and proper data validation have to be verified for historical records. These are but a few of many critical aspects for a robust and trustable data interpretation needed in the Evidence Based Medicine era. Clinicians always wish to be able to quickly interpreter diagnostic records to discriminate, or alternatively correlate, coherent groups of patient’s records according to either descriptive characters or variable units. Practically, patient’s records are stored in spread-sheet or database which change pending on the clinical trial scope; moreover, data entry and its validation is usually poor, hence physician are used to send raw-data to the statistician without contributing, for instance, with parametric and non-parametric indication on usable distribution. We address this problem by introducing a simple “weighted” model approached with the Unique Factorisation Domain theory: records can be compare by matching each other through a score overlap and clinician can modulate tolerance of closeness stringency criteria. An intuitive paradigm of records matching method (RMM) is presented and discussed with example, computational design and programming prototyping model; freely available material concerning real-world application, are also provided by the authors

Associated Top Quark-Higgs Boson Production at the LHC

We compute the O(alpha_s^3) inclusive cross section for the process pp -> t-tbar-h in the Standard Model, at sqrt(s)=14 TeV. The next-to-leading order corrections drastically reduce the renormalization and factorization scale dependence of the Born cross section and increase the total cross section for renormalization and factorization scales larger than m_t. These corrections have important implications for models of new physics involving the top quark.Comment: 5 pages, 4 figures, RevTeX

2D granular flows with the μ(I)\mu(I) rheology and side walls friction: a well balanced multilayer discretization

We present here numerical modelling of granular flows with the $\mu(I)$ rheology in confined channels. The contribution is twofold: (i) a model to approximate the Navier-Stokes equations with the $\mu(I)$ rheology through an asymptotic analysis. Under the hypothesis of a one-dimensional flow, this model takes into account side walls friction; (ii) a multilayer discretization following Fern\'andez-Nieto et al. (J. Fluid Mech., vol. 798, 2016, pp. 643-681). In this new numerical scheme, we propose an appropriate treatment of the rheological terms through a hydrostatic reconstruction which allows this scheme to be well-balanced and therefore to deal with dry areas. Based on academic tests, we first evaluate the influence of the width of the channel on the normal profiles of the downslope velocity thanks to the multilayer approach that is intrinsically able to describe changes from Bagnold to S-shaped (and vice versa) velocity profiles. We also check the well balance property of the proposed numerical scheme. We show that approximating side walls friction using single-layer models may lead to strong errors. Secondly, we compare the numerical results with experimental data on granular collapses. We show that the proposed scheme allows us to qualitatively reproduce the deposit in the case of a rigid bed (i. e. dry area) and that the error made by replacing the dry area by a small layer of material may be large if this layer is not thin enough. The proposed model is also able to reproduce the time evolution of the free surface and of the flow/no-flow interface. In addition, it reproduces the effect of erosion for granular flows over initially static material lying on the bed. This is possible when using a variable friction coefficient $\mu(I)$ but not with a constant friction coefficient

Replacing iron-folic acid with multiple micronutrient supplements among pregnant women in Bangladesh and Burkina Faso: costs, impacts, and cost-effectiveness.

Consumption of multiple micronutrient supplements (MMS) during pregnancy offers additional benefits compared with iron-folic acid (IFA) supplementation, but the tablets are more expensive. We estimated the effects, costs, and cost-effectiveness of hypothetically replacing IFA supplements with MMS for 1 year in Bangladesh and Burkina Faso. Using baseline demographic characteristics from LiST and effect sizes from a meta-analysis, we estimated the marginal effects of replacing IFA with MMS on mortality, adverse birth outcomes, and disability-adjusted life years (DALYs) averted. We calculated the marginal tablet costs of completely replacing MMS with IFA (assuming 180 tablets per covered pregnancy). Replacing IFA with MMS could avert over 15,000 deaths and 30,000 cases of preterm birth annually in Bangladesh and over 5000 deaths and 5000 cases of preterm birth in Burkina Faso, assuming 100% coverage and adherence. We estimated the cost per death averted to be US$175-185 in Bangladesh and$112-125 in Burkina Faso. Cost per DALY averted ranged from $3 to$15, depending on the country and consideration of subgroup effects. Our estimates suggest that this policy change would cost-effectively save lives and reduce life-long disabilities. Improvements in program delivery and supplement adherence would be expected to improve the cost-effectiveness of replacing IFA with MMS