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Abstract: The objective of this study was to determine the effect of deoxynivalenol (DON) on in vitro rumen fermentation by assessing pH, ammonia-N, total gas, volatile fatty acid (VFA) production, and DON degradation under the context of two different carbon sources (corn starch or cellulose). Fifty millilitre of ruminal fluid:buffer (1:1) was incubated for up to 6h with four possible treatments: corn starch 1.5g, corn starch 1.5g+DON at 40mg/kg dry matter (DM), cellulose 1.5g, and cellulose 1.5g+DON at 40mg/kg DM. Our results indicate that carbon source appears to markedly influence all rumen fermentative parameters (P<0.05), whereas DON negatively impacted certain aspects of rumen fermentative capacity, such as ammonia-N and total gas production, especially acetate and propionate production having been reduced (P<0.01). Therefore, it may be possible for carbon source to influence and limit the degree upon which DON''s effects are exerted. DON degradation rate was especially influenced by carbon source context (P=0.0105) with cellulose leading to a higher rate of DON degradation than that of corn starch. This would indicate that concentrate/forage ratio, in the diet, may have an effect on DON degradation. [Copyright &y& Elsevier]

Inversion layer technique can increase the centre frequency (f0) and the −6 dB bandwidth of the ultrasound transducer without reducing thickness of active material. However, it suffers from the reduced −6 dB bandwidth when the centre frequency is increased more than 1.5f0. A modified inversion technique is proposed and applied it to high‐frequency intravascular ultrasound (IVUS) transducer. The performance was computationally verified by using finite element method (FEM) simulation. The proposed IVUS transducer consists of two sub‐elements with each aperture size of 0.6 × 0.6 mm, and each sub‐element has different types of inversion layer using PMN‐PT and PZT‐5H. The initial thickness of overall active material was designed for 40 MHz centre frequency and the FEM simulation showed that the centre frequency was increased by about 1.8f0 maintaining the −6 dB fractional bandwidth compared with the conventional transducer. [ABSTRACT FROM AUTHOR]

In order to understand repetitive convective transport and its flow physics over the flat tip of a turbine blade, high-spatial resolution measurements of thermal load and aerodynamic loss are performed in a large-scale cascade. The thermal load distributions measured with the naphthalene sublimation technique show that for two tip gaps of h/s = 1.0% and 2.0%, there is a repetitive change of thermal load upstream of the mid-chord, and wider tip gap makes thermal load change more severe but less repetitive. The mean distance between the neighboring peaks of thermal load in the direction normal to local flow for h/s = 2.0% is twice the one for h/s = 1.0%. Present total pressure measurements show that in the area of repetitive thermal load change for h/s = 2.0%, there exists a distinct repetitive loss change only near the tip surface. A qualitative flow model in the area of repetitive change is proposed for h/s = 2.0%. According to the flow model, the separation bubble undergoes a wave-like repetitive change in its thickness and length. Just behind the ridge of the wave-like separation bubble, low thermal load coexists with high loss, whereas just behind its valley, high thermal load coexists with low loss. [ABSTRACT FROM AUTHOR]

The quality of focusing in high‐frequency ultrasound imaging is significantly affected by the length of the depth of field (DOF). A dual‐concentric transducer combined with a phase‐apodisation scheme is presented to achieve the extended DOF maintaining signal‐to‐noise ratio. As a preliminary study, computational simulation by using a Field‐II program is conducted to demonstrate the feasibility. A dual‐concentric transducer is composed of a disc‐ and a ring‐type element with confocal apertures. When two input signals with 0° and 180° phases are simultaneously applied to the inner and outer elements, a bifocal‐zone is generated in the axial direction. The overall − 6 dB DOF is 40% longer compared with a single element transducer. Thus, the proposed scheme can be a potential approach to increase the DOF for high‐frequency ultrasound imaging. [ABSTRACT FROM AUTHOR]

Real‐time ultrasound imaging during high‐intensity focused ultrasound (HIFU) surgery allows for tracking tissue movement and monitoring feedback from a treated target. However, the reflected HIFU interference signals deteriorate the quality of imaging signals received by an imaging transducer during simultaneous therapy and imaging. The purpose of this Letter is to demonstrate that those HIFU interference signals can be significantly reduced in the brightness‐mode image by using a coded excitation scheme with adaptive notch filtering. A prototype integrated HIFU/imaging transducer was used to experimentally demonstrate the performance of the proposed method. [ABSTRACT FROM AUTHOR]