A maximum stress at a distance criterion for the prediction of crack propagation in adhesively-bonded joints

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Toll-like receptor 3 blockade in rhinovirus-induced experimental asthma exacerbations:A Randomized Controlled Study

BACKGROUND: Human rhinoviruses (HRVs) commonly precipitate asthma exacerbations. Toll-like receptor 3, an innate pattern recognition receptor, is triggered by HRV, driving inflammation that can worsen asthma. OBJECTIVE: We sought to evaluate an inhibitory mAb to Toll-like receptor 3, CNTO3157, on experimental HRV-16 inoculation in healthy subjects and asthmatic patients. METHODS: In this double-blind, multicenter, randomized, parallel-group study in North America and Europe, healthy subjects and patients with mild-to-moderate stable asthma received single or multiple doses of CNTO3157 or placebo, respectively, and were then inoculated with HRV-16 within 72 hours. All subjects were monitored for respiratory symptoms, lung function, and nasal viral load. The primary end point was maximal decrease in FEV1 during 10 days after inoculation. RESULTS: In asthmatic patients (n = 63) CNTO3157 provided no protection against FEV1 decrease (least squares mean: CNTO3157 [n = 30] = -7.08% [SE, 8.15%]; placebo [n = 25] = -5.98% [SE, 8.56%]) or symptoms after inoculation. In healthy subjects (n = 12) CNTO3157 versus placebo significantly attenuated upper (P = .03) and lower (P = .02) airway symptom scores, with area-under-the-curve increases of 9.1 (15.1) versus 34.9 (17.6) and 13.0 (18.4) versus 50.4 (25.9) for the CNTO3157 (n = 8) and placebo (n = 4) groups, respectively, after inoculation. All of the severe and 4 of the nonserious asthma exacerbations occurred while receiving CNTO3157. CONCLUSION: In summary, CNTO3157 was ineffective in attenuating the effect of HRV-16 challenge on lung function, asthma control, and symptoms in asthmatic patients but suppressed cold symptoms in healthy subjects. Other approaches, including blockade of multiple pathways or antiviral agents, need to be sought for this high unmet medical need

CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics

This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at $z\sim1.5-8$, and to study Type Ia SNe beyond $z>1.5$. Five premier multi-wavelength sky regions are selected, each with extensive multiwavelength observations. The primary CANDELS data consist of imaging obtained in the Wide Field Camera 3 / infrared channel (WFC3/IR) and UVIS channel, along with the Advanced Camera for Surveys (ACS). The CANDELS/Deep survey covers \sim125 square arcminutes within GOODS-N and GOODS-S, while the remainder consists of the CANDELS/Wide survey, achieving a total of \sim800 square arcminutes across GOODS and three additional fields (EGS, COSMOS, and UDS). We summarize the observational aspects of the survey as motivated by the scientific goals and present a detailed description of the data reduction procedures and products from the survey. Our data reduction methods utilize the most up to date calibration files and image combination procedures. We have paid special attention to correcting a range of instrumental effects, including CTE degradation for ACS, removal of electronic bias-striping present in ACS data after SM4, and persistence effects and other artifacts in WFC3/IR. For each field, we release mosaics for individual epochs and eventual mosaics containing data from all epochs combined, to facilitate photometric variability studies and the deepest possible photometry. A more detailed overview of the science goals and observational design of the survey are presented in a companion paper.Comment: 39 pages, 25 figure

Micromechanical modeling of dual-phase elasto-plastic materials : influence of the morphological anisotropy, continuity and transformation of the phases/

The goal of this thesis is to determine the relationship between the macroscopic stress and the macroscopic strain for a variety of complex multiphase materials exhibiting rate-independent non-linear response at the micro-scale, based on experimental data obtained both at the local and macroscopic scales. A micro-macro secant mean field model (SMF model) based on the result of Eshelby and the approach of Mori and Tanaka is developed to model the behaviour of three particular systems which we have worked out by ourselves: 1) a ferrite-martensite steel produced by rolling in which we quantify the plastic anisotropy due to the morphological texture in terms of the Lankford's coefficient and pseudo yield surface; 2) a composite made of two continuous and interpenetrating phases: an aluminium matrix reinforced by a preform of sintered Inconel601 fibres. We quantify the coupled effects of temperature and phases co-continuity on the phases and overall stresses; 3) a TRIP-aided multiphase steel, in which the dispersed metastable austenite phase transforms to martensite. We derive the relationship between the overall uniaxial elastoplastic response and the progress of phase transformation, itself influenced by the thermodynamical, microstructural and mechanical properties. The stress-state dependence of the martensitic transformation is enlightened and explained. We demonstrate the existence of thermomechanical treatments leading to optima of ductility and strength-ductility balance. Finally, we show that the formability of TRIP-aided multiphase steels depends on the stability criterion.(FSA 3)--UCL, 200

Micro-macro modeling of spheroidal cast iron: parameters identification by inverse analysis

In a previous study, a generic micro-macro mechanical model based on the coupling of an incremental mean-field model [1, 4, 5] with the Gurson-Tvergaard (GT) porous plastic law [2, 6] has been developed for the prediction of the mechanical properties of multiphase materials with a large volume fraction of voids. This model has been used in the framework of the FP6 PROHIPP European project to investigate the link between the microstructure and the mechanical properties of spheroidal cast iron. In this contribution, experimental results are presented and an inverse analysis procedure is proposed to adjust the parameters of the model

A XFEM-based probabilistic damage tolerant approach with Morfeo/Crack for Abaqus

A computational chain is developed to compute probabilities of failure using the XFEM and Level Set methods implemented in Morfeo/Crack for Abaqus. Monte-Carlo First Order Reliability Method (FORM) approaches with Knowledge Based Metamodels or Radial Basis Functions Networks built from direct XFE simulations are constructed. The computed probabilities of failure are compared, the computational efficiency of the different methods is assessed