Identification of taste solutions and their binary mixtures using SH-SAW resonator-based taste sensor

A novel two-port resonator-based shear-horizontal surface acoustic wave (SH-SAW) sensor has been designed for liquid analysis. The device operates at a wireless ISM frequency of 434 MHz and is built on a 36deg YX LiTaO3 piezoelectric substrate. It relies on a purely physical detection mechanism and it has been designed to function without the need for analyte-specific coatings. The sensor proved successful in identification of all six tastes: alongside the four classical tastes - saltiness, sweetness, sourness, and bitterness - test samples included solutions simulating the umami and metallic tastes. The taste sensor was also able to separate between samples of the same taste class (e.g. caffeine and quinine hydrochloride of the bitter class) as well as to detect and classify samples of the same substance with different concentrations. Furthermore, the potential to identify binary mixtures and separate them from original component solutions was tested and confirmed experimentally

On a generalization of the Laplace approximation

Laplace approximation is one commonly used approach to the calculation of difficult integrals arising in Bayesian inference and the analysis of random effects models. Here we outline a procedure which is an extension of the Laplace approximation and which attempts to find changes of variable for which the integrand becomes approximately a product of one-dimensional functions. When the integrand is a product of one-dimensional functions, an approximation to the integral can be obtained using one-dimensional quadrature. The approximation is exact for a broader class of functions than the ordinary Laplace approximation and can be applied when the integrand is not smooth at the mode. As an illustration of this last point we consider calculation of marginal likelihoods for smoothing parameter selection in the lasso.

Taste sensors utilizing high-frequency SH-SAW devices

Recent interest in the development of taste sensors has been motivated by their potential application in the food and beverage industries as well as environmental monitoring. This paper describes the development of novel high-frequency dual delay line and two-port resonator shear-horizontal surface acoustic wave (SH-SAW) microsensors for liquid analysis. The acoustic devices have been designed to function without the need for analyte-specific coatings and to operate at the wireless ISM frequency of 433 MHz; the sensors are small, robust and are built on a piezoelectric substrate (36 degrees YX LiTaO3). Liquid samples are introduced to the active sensing area via a microfluidic cell that has been fabricated using microstereolithography (MSL) and then attached to the SH-SAW sensor substrate. A low cost flow system has been developed and integrated with the sensor housing to create a fully automated measurement system. Tests have been performed on aqueous solutions with different tastants representing not only the four basic tastes of saltiness, sweetness, sourness, and bitterness but also of umami and metallic. Results show that good discrimination between the different taste samples is possible using both delay-line and resonator type piezoelectric devices. (c) 2006 Elsevier B.V. All rights reserved

Antibody and Nanobody Radiolabeling with Copper-64: Solid vs. Liquid Target Approach

Antibody and nanobody-based copper-64 radiopharmaceuticals are increasingly being proposed as theranostic tools in multiple human diseases. While the production of copper-64 using solid targets has been established for many years, its use is limited due to the complexity of solid target systems, which are available in only a few cyclotrons worldwide. In contrast, liquid targets, available in virtually in all cyclotrons, constitute a practical and reliable alternative. In this study, we discuss the production, purification, and radiolabeling of antibodies and nanobodies using copper-64 obtained from both solid and liquid targets. Copper-64 production from solid targets was performed on a TR-19 cyclotron with an energy of 11.7 MeV, while liquid target production was obtained by bombarding a nickel-64 solution using an IBA Cyclone Kiube cyclotron with 16.9 MeV on target. Copper-64 was purified from both solid and liquid targets and used to radiolabel NODAGA-Nb, NOTA-Nb, and DOTA-Trastuzumab conjugates. Stability studies were conducted on all radioimmunoconjugates in mouse serum, PBS, and DTPA. Irradiation of the solid target yielded 13.5 ± 0.5 GBq with a beam current of 25 ± 1.2 μA and an irradiation time of 6 h. On the other hand, irradiation of the liquid target resulted in 2.8 ± 1.3 GBq at the end of bombardment (EOB) with a beam current of 54.5 ± 7.8 μA and an irradiation time of 4.1 ± 1.3 h. Successful radiolabeling of NODAGA-Nb, NOTA-Nb, and DOTA-Trastuzumab with copper-64 from both solid and liquid targets was achieved. Specific activities (SA) obtained with the solid target were 0.11, 0.19, and 0.33 MBq/μg for NODAGA-Nb, NOTA-Nb, and DOTA-trastuzumab, respectively. For the liquid target, the corresponding SA values were 0.15, 0.12, and 0.30 MBq/μg. Furthermore, all three radiopharmaceuticals demonstrated stability under the testing conditions. While solid targets have the potential to produce significantly higher activity in a single run, the liquid process offers advantages such as speed, ease of automation, and the feasibility of back-to-back production using a medical cyclotron. In this study, successful radiolabeling of antibodies and nanobodies was achieved using both solid and liquid targets approaches. The radiolabeled compounds exhibited high radiochemical purity and specific activity, rendering them suitable for subsequent in vivo pre-clinical imaging studies

Methods for quantitative susceptibility and R2*mapping in whole post-mortem brains at 7T applied to amyotrophic lateral sclerosis

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