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The energy content of finishing diets offered to feedlot cattle may vary across countries. We assumed that the lower is the energy content of the finishing diet, the shorter can be the adaptation period to high-concentrate diets without negatively impacting rumen health while still improving feedlot performance. This study was designed to determine the effects of adaptation periods of 6, 9, 14 and 21 days on feedlot performance, feeding behaviour, blood gas profile, carcass characteristics and rumen morphometrics of Nellore cattle. The experiment was designed as a completely randomised block, replicated 6 times, in which 96 20-month-old yearling Nellore bulls (391.1 ± 30.9 kg) were fed in 24 pens (4 animals/pen) according to the adaptation period adopted: 6, 9, 14 or 21 days. The adaptation diets contained 70%, 75% and 80.5% concentrate, and the finishing diet contained 86% concentrate. After adaptation, one animal per pen was slaughtered (n = 24) for rumen morphometric evaluations and the remaining 72 animals were harvested after 88 days on feed. Orthogonal contrasts were used to assess linear, quadratic and cubic relationships between days of adaptation and the dependent variable. Overall, as days of adaptation increased, final BW (P = 0.06), average daily gain (ADG) (P = 0.07), hot carcass weight (P = 0.04) and gain to feed ratio (G : F) (P = 0.07) were affected quadratically, in which yearling bulls adapted by 14 days presented greater final BW, ADG, hot carcass weight and improved G : F. No significant (P > 0.10) days of adaptation effect was observed for any of feeding behaviour variables. As days of adaptation increased, the absorptive surface area of the rumen was affected cubically, where yearling bulls adapted by 14 days presented greater absorptive surface area (P = 0.03). Thus, Nellore yearling bulls should be adapted by 14 days because it led to improved feedlot performance and greater development of rumen epithelium without increasing rumenitis scores. [ABSTRACT FROM AUTHOR]

• Microconcrete is subjected to SHPB dynamic quasi-oedometric compression tests. • Damage process is visualized with MHz X-ray phase-contrast imaging. • Time-resolved measurements of sample axial strain and radial expansion are produced. • Non-linear analysis of mechanical response of polymeric confining cell is considered. • Microcracking develops from the equatorial zone of large spherical pores. In the present study, microconcrete (MC) samples were exposed to dynamic quasi-oedometric compression (QOC) tests and visualised in-situ by the means of MHz synchrotron X-ray phase-contrast imaging in the ESRF synchrotron in order to analyse the damage mechanisms governing the mechanical behaviour of concrete under high-strain-rate confined compression. To do so, small cylindrical samples were placed in polymeric confinement cell and dynamically compressed along their axial direction using SHPB (Split-Hopkinson Pressure Bar) set-up available in ID19 beamline in the European Synchrotron Radiation Facility (ESRF). The damage process was visualized with MHz X-ray phase-contrast imaging along with an ultra-high-speed camera operating at a recording frequency approximately 1 Mfps (million frames per second i.e., 880 ns interframe time). The axial stress and strain temporal profiles were obtained from standard Kolsky's (SHPB) data processing. In addition, data of radial stress and strain within the sample were deduced from non-linear analysis of the mechanical behaviour of the polycarbonate confining cell instrumented with a strain gauge. Finally, the onset and growth of microcracking observed from the equatorial zone of large spherical pores is correlated with deviatoric and pressure measurements showing how the pore collapse process develops during the applied mechanical loading. [ABSTRACT FROM AUTHOR]

The increasing use of digital twins for design in aerospace industry requires the development of validation tests at an intermediate scale prior to full-scale testing. In this paper, a new experimental set-up called Soft Projectile Impact Three-Point Bending (SPITPB) has been investigated by numerical and experimental methods. SPITPB corresponds to an intermediate-scale test representative of a bird strike test, dedicated to the study of the strength of adhesively bonded assemblies. The experimental set-up is detailed in terms of projectile, specimen and boundaries conditions. Three impact velocities leading to three different levels of damage of the adhesive joint are investigated, from intact to highly damaged specimens. A numerical simulation of the SPITPB is achieved with the commercial code LS-DYNA®. A Smooth Particle Hydrodynamics model is used to describe the projectile, while the specimen is modelled with a finite element approach. The focus is on the structural response of the specimen and the damage of the adhesive joint. Numerical simulation results demonstrate a good correlation with the experimental data in terms of structural displacement, local strain and post-mortem crack length observations. The dynamic behaviour of the adhesive and the failure model are finally validated as a result of this correlation. • Mechanical strength of adhesively-bonded joints under soft impact. • A three-point bending impact test on bonded assemblies was proposed. • A numerical modelling of the adhesive joint was introduced for dynamic loading. • A good correlation between numerical and experimental bird strike test was observed. • Several levels of damage to the adhesive joint have been investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • UHMWPE Tensylon is successfully thermaly spraying coated by 200 µm thick Alumina by using an intermediate Zn layer. • LASAT method has been successfully experienced to assess the coating adhesion at high strain rates. • The obtained hybridized structure reduces the rear face velocity under shock by more than half, very effective for impact resilience. Composite materials are increasingly inescapable in engineered systems in various industrial fields, given their high strength to weight ratio for increasing autonomy, reducing energy consumption and enhancing mechanical strength of high added value products. However, their out-of-plane resistance could be improved by multimaterial assembly for structural hybridization. The purpose of this study is to explore the possibility of upgrading the shock resistance of UHMWPE Tensylon® by alumina coating. Thermal spraying was used for alumina deposition on UHMWPE and bond strength assessment of the obtained assembly was performed by Laser Adhesion Test (LASAT). During experiments, free surface velocities of specimens were recorded by the use of Photonic Doppler Velocimetry (PDV) allowing relevant observations complementary to optical observations. From the PDV analysis and cross section observations by microscopy, a diagnostic of the decohesion of the interface is proposed. The study shows the possibility of assembling alumina on UHMWPE to strengthen its shock resistance and makes now possible the improvement of the study of deposition process parameters thanks to LASAT evaluations. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The aim of this open/retrospective study was to evaluate the outcomes of intensive care unit patients treated for fulminant hepatic failure (FHF) for predictive indices. Methods: All patients were recovered in the intensive care units with a diagnosis of FHF. We considered three groups of patients: (1) survivors, deceased, and transplanted. Subjects: All patients were fully screened, including liver function indices such as AST, ALT, total and bound bilirubin, albumin and pre-albumin, factors 5 and 7, alpha fetal protein (α-PP), other coagulation tests (PT, aPTT, INR, ATIII), and renal function (BUN and creatinine) parameters. For each patient Apache II score was calculated upon admission to the intensive care unit. Results: Apache II score showed efficacy. α-PP increased in both surviving and deceased, but not in the transplanted group. After intensive care unit admission, AST and ALT peaks were higher in the deceased DP than in the transplanted group. The INR value at the third day after ICU admission improved in the survivors compared with the other two cohorts. Factor 5 levels were lower among patients undergoing transplantation, but increased in the other two groups. The prognosis was strictly dependent upon the development of renal failure. Conclusion: The Apache II score was a sensitive predictive index for outcome. α-PP and factor 5 were not related to outcome, but useful for decision making when determining potential liver transplantation. INR can be used as a prognostic index. Intensive treatment beforehand is of primary importance to prevent multiple organ failure. [Copyright &y& Elsevier]