Nutrient digestibility and endogenous protein losses in the foregut and small intestine of weaned dairy calves fed calf starters with conventional or enzyme-treated soybean meal

The aims of this experiment were (1) to compare the effects of a soybean meal with an enzymatic treatment (ESBM) to reduce the concentration of antinutritional factors versus a standard soybean meal (SBM) on foregut and small intestine digestion in weaned dairy calves and (2) to estimate the endogenous losses of crude protein (CP) in the small intestine. Our hypothesis was that a diet containing ESBM instead of SBM would improve ruminal and small intestine digestion and absorption of nutrients. A T-cannula was placed in the duodenum, and a second T-cannula was installed in the distal ileum of 12 Holstein calves at approximately 3 wk of age. Calves were weaned on d 42, and on d 50 they were assigned randomly to a quadruplicated 3 × 3 Latin square with 10-d periods. Digesta samples were collected on d 7 and 8 from the ileum and d 9 and 10 from the duodenum. The diets were fed for ad libitum intake and consisted of a calf starter (CS) of 20% CP with SBM as the main source of protein (CTRL), and an isonitrogenous CS with an ESBM instead of SBM (ENZT). A third diet with a low content of CP (10%) and no soy protein was fed to estimate endogenous N losses and digestibilities of test ingredients. Flows and digestibilities of nutrients were compared between CTRL and ENZT and their test ingredients (SBM vs. ESBM, respectively). Duodenal net flows of CP and total AA as well as ruminal microbial protein synthesis per kilogram of digested CP were greater, and flow of nonprotein N and CP true (corrected by endogenous and microbial flows) foregut digestibility were lower with ENZT than CTRL. The apparent small intestine digestibilities of CP and total AA were greater for ESBM than SBM, but there were no differences between the CTRL and ENZT diets. We observed no differences in digestibilities at the duodenum or ileum of starch or NDF, but true small intestine digestibilities of CP and all AA were greater with ENZT than CTRL. Total endogenous protein losses in the small intestine estimated from calves fed the low-CP with no soy protein diet were 37 ± 1.5 g of CP and 29 ± 1.4 g of AA/kg of DMI. These values may be considered the basal endogenous losses as they are similar to values obtained with the regression method, which estimates N losses when dietary N is null. Our results indicated that the inclusion of an ESBM improved the efficiency of ruminal microbial protein synthesis per digested kilogram of organic matter and CP, and increased CP and AA absorption in the small intestine despite a greater proportion of undigested dietary protein entering the duodenum.     

On the time-domain scattering by a passive classical frequency dependent wedge-shaped region in a lossy dispersive medium

The time-scattering of an electromagnetic wave by a wedge-shaped region in a lossy medium, both with frequency dependent electric characteristics, is analyzed for plane wave and line source illuminations. New exact analytical expressions, satisfying explicitely the causality and allowing useful physical decompositions of the field, are obtained in these cases, using the particularities of the harmonic response in Sommerfeld-Maliuzhinets integral, especially original properties of the spectral function attached to it.     

Real-time control of video surveillance systems with program supervision techniques

In this article, we describe a knowledge-based controlled platform using program supervision techniques. This platform eases the creation and the configuration of video surveillance systems. Several issues need to be addressed to provide a correct system configuration: (1) to choose, among a library of programs, those which are best satisfying a given user request, (2) to assign a correct value for each program parameter, (3) to evaluate performances and to guarantee a performance rate which is satisfactory regarding end-user requirements. This platform is composed of three main components: the library of programs, the knowledge base and the control component. The knowledge is either given by experts or learnt by the system. The control is generic in the sense that it is independent of any application. To validate this platform, we have built and evaluated six video surveillance systems which are featured with three properties: adaptability, reliability and real-time processing.     

Multiphysics modeling and optimization of mechatronic multibody systems

Modeling mechatronic multibody systems requires the same type of methodology as for designing and prototyping mechatronic devices: a unified and integrated engineering approach. Various formulations are currently proposed to deal with multiphysics modeling, e.g., graph theories, equational approaches, co-simulation techniques. Recent works have pointed out their relative advantages and drawbacks, depending on the application to deal with: model size, model complexity, degree of coupling, frequency range, etc. This paper is the result of a close collaboration between three laboratories, and aims at showing that for “non-academic” mechatronic applications (i.e., issuing from real industrial issues), multibody dynamics formulations can be generalized to mechatronic systems, for the model generation as well as for the numerical analysis phases. Model portability being also an important aspect of the work, they must be easily interfaced with control design and optimization programs. A global “demonstrator”, based on an industrial case, is discussed: multiphysics modeling and mathematical optimization are carried out to illustrate the consistency and the efficiency of the proposed approaches.     

Coriolis effects in the dynamics of a rotating elastic structure

Summary Small oscillations of a rotating elasticum with a mass at the free end are investigated with Poincaré-Lindstedt series. It is shown that the mass moves on a figure-eight shaped curve in a direction determined by the sign of the angular velocity and hence that the Coriolis force influences the motion.     

Characterization of the epidermal growth factor receptor in pig oviduct and endometrium

Two different plaque variants of Japanese encephalitis virus were selected from a wild-type Taiwanese isolate using Vero cells. One variant was found to exhibit small plaque morphology with retarded virus replication kinetics in Vero cells, and was demonstrated to be resistant to monoclonal antibody (mAb) E3.3 neutralization. The other variant showed large plaque morphology, was sensitive to mAb E3.3 neutralization, and manifested reduced virulence in mice on both intracranial and intraperitoneal inoculations. These two variants propagated in Vero cells retained high levels of infectivity but had relatively low HA titers as compared with the parent strain. The envelope sequences of these two variants showed four amino acid differences at residues E-85 (Glu/Arg), E-306 (Glu/Gly), E-331 (Ser/Arg), and E-387 (Met/Arg). Our results indicated the neutralizing epitope of Japanese encephalitis virus did not overlap with virus virulence determinant.     

Different immunological mechanisms contribute to cartilage destruction in antigen-induced arthritis

Antigen-induced arthritis in guinea pigs was used as a model to investigate the pathogenic mechanisms responsible for cartilage destruction in chronic joint inflammation. The activation of macrophages, their effects on cartilage metabolism, and the development of autoimmunity to cartilage constituents were studied during the progression of arthritis. The results show that in arthritic animals the macrophages are systemically activated, with a peak in the early phase of inflammation. Interleukin 1, produced by the activated cells, suppresses the proteoglycan synthesis in cartilage explants and cultured chondrocytes and increases the proliferation of the cells in vitro. During the progression of arthritis humoral and cell-mediated immune responses to collagen type II and cartilage proteoglycans occur correlating with the severity of arthritis. It is concluded that different immunological mechanisms may be involved in cartilage destruction during antigen-induced arthritis. Mediator-induced metabolic reactions dominate in the early phase, whereas autoimmunity to cartilage might play an essential role in later phases of arthritis.     

DynMo-TE: Dynamic simulation model of space reactor power system with thermoelectric converters

A space reactor power system (SRPS) has been developed for avoidance of single point failures in reactor cooling and energy conversion. The sectored compact reactor (SCoRe) in this system is lithium-cooled and the reactor core is divided into six equal sectors with liquid metal heat pipes dividers. These reactor sectors are neutronically, but not thermal-hydraulically, coupled. Each sector has its own primary and secondary circulating lithium loops, which are thermally coupled both in a SiGe thermoelectric (TE) power conversion assembly (PCA) and a thermoelectric conversion assembly (TAC) that powers the electromagnetic pumps in the primary and secondary loops. Each secondary loop also has a separate, segmented radiator panel that is optimized for low specific mass and low liquid lithium inventory. The primary loops transport the thermal power generated in the reactor to six PCAs that nominally supply a total of 111.5 kW_e to the load at 450 V DC. Each of the 12 primary and secondary loops has its own bellows-type accumulator that is designed to regulate the lithium pressures in the loops. A dynamic simulation model of this thermoelectric SRPS (DynMo-TE) has been developed and used to investigate the transient operation of the system during a startup from a fully-thawed condition at 600 K, to nominal steady-state operation at which the lithium coolant exits the reactor at only 1179 K. Also investigated is the load-following characteristic of the SCoRe-TE SRPS, following a change in the electrical load demand.     

Kinetics of catalyzed and non-catalyzed oxidation of soot from a diesel engine

To comply with the new regulations on particulate matter, car manufacturers more and more commonly use diesel particulate filters (DPF). The working of these systems needs to periodically burn soot that has been accumulated during the loading of the DPF. This paper describes the kinetics of the non-catalytic and catalytic oxidation of real diesel soot with oxygen. From these experiments, mechanisms for catalyzed and non-catalyzed soot oxidation have been proposed.     

Possibilities and extension of XRD material response analysis in failure research for the advanced evaluation of the damage level of Hertzian loaded components

Due to clearly distinguishable damage symptoms, it is differentiated between the surface and sub‐surface failure mode of rolling bearings. Material states red out by X‐ray diffraction (XRD) residual stress measurements point to a variety of loading conditions especially at raceway surfaces that are associated with several competing failure mechanisms. The corresponding lifetime reduction can range from the lower fatigue strength region to material ratcheting in extreme cases. Relevant position of the microstructural changes and nature of the failure mechanisms are characterized. The time alteration of the XRD material parameters measured at or near the surface and at the depth of the maximum equivalent stress correlates, in a different manner, with the statistical parameter of the 10 % bearing life. Both failure modes are illustrated by concrete examples. Contaminated lubricant and boundary lubrication, which represent practically important surface‐induced failures, are discussed in more detail. Gray staining, i.e. shallow pitting, often occurs without distinct indication of global material aging by means of XRD characteristics. Here, scanning electron microscopy observations and electron microprobe analyses point to corrosion fatigue as acting surface failure mechanism. The interaction between material and lubricant under complex loading regimes particularly of mixed friction and corrosion opens further failure research areas in the field of tribology.