Abstract. Anisotropic wet chemical etching of quartz is a bulk micromachining process for the fabrication of Micro-Electro-Mechanical Systems (MEMS), such as resonators and temperature sensors. Despite the success of the Continuous Cellular Automaton (CCA) for the simulation of wet etching of silicon, the simulation of the same process for quartz has received little attention -especially from an atomistic perspective-resulting in a lack of accurate modeling tools. This paper analyzes the crystallographic structure of the main surface orientations of quartz and proposes a novel classification of the surface atoms as well as an Evolutionary Algorithm (EA) to determine suitable values for the corresponding atomistic removal rates. Not only the presented Evolutionary Continuous Cellular Automaton (ECCA) reproduces the correct macroscopic etch rate distribution for quartz hemispheres but it is also capable of performing fast and accurate 3D simulations of MEMS structures. This is shown by several comparisons between simulated and experimental results and, in particular, by a detailed, quantitative comparison for an extensive collection of trench profiles.

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Due to the high intensification of poultry production in recent years, white chicken breast striping is one of the most frequently seen myopathies. The aim of this research was to develop a spectrophotometry-based sensor to detect white striping physiopathy in chicken breast meat in whole chicken carcasses with skin. Experiments were carried out using normal and white striping breasts. In order to understand the mechanism involved in this physiopathy, the different tissues that conform each breast were analyzed. Permittivity in radiofrequency (40 Hz to 1 MHz) was measured using two different sensors; a sensor with two flat plates to analyze the whole breast with skin (NB or WSB), and a two needles with blunt-ended sensor to analyze the different surface tissues of the skinless breast. In the microwave range (500 MHz to 20 GHz), permittivity was measured as just was described for the two needles with blunt-ended sensor. Moreover, fatty acids composition was determined by calorimetry techniques from −40 °C to 50 °C at 5 °C/min after previously freeze-drying the samples, and pH, microstructure by Cryo-SEM and binocular loupe structure were also analyzed. The results showed that the white striping physiopathy consists of the partial breakdown of the pectoral muscle causing an increase in fatty acids, reducing the quality of the meat. It was possible to detect white striping physiopathy in chicken carcasses with skin using spectrophotometry of radiofrequency spectra.

Abstract-Current PET systems with fully digital trigger rely on early digitization of detector signals and the use of digital processors, usually FPGAs, for recognition of valid gamma events on single detectors. Timestamps are assigned and later used for coincidence analysis. In order to maintain a decent timing resolution for events detected on different acquisition boards, it is necessary that local timestamps on different FPGAs be synchronized. Sub-nanosecond accuracy is mandatory if we want this effect to be negligible on overall timing resolution. This is usually achieved by connecting all boards to a common backplane with a precise clock delivery network; however, this approach forces a rigid structure on the whole PET system and may pose scalability problems.As an alternative, we propose a backplane-less PET system architecture in which DAQ boards are connected by single fullduplex high-speed data links. Data encoding with embedded clock is used to correct frequency differences between local oscillators. Timestamp synchronization between FPGAs with clock period resolution is maintained by means of data transfers in a way similar to the IEEE 1588 standard. Finer resolution is achieved by reflection of received clocks and phase difference measurement on the transmitter. It is crucial that data transceivers have very low latency uncertainty in order to achieve the desired timestamp accuracy; we discuss the availability of off-the-shelf hardware for these implementations.