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Society has increasingly come to appreciate the relationship between people and pets, and therefore, the demand for research into this subject has also been growing. In Brazil, tools designed to assess the human-animal relationship are still scarce, and so far, there is no tool, adapted for the Brazilian context, designed to evaluate the bond between people and their animals. The Lexington Attachment to Pets Scale (LAPS) is a scale that aims to measure the degree of attachment that an owner has for their pet. It is one of the most used tools to assess the emotional bond between people and their animals. The aim of this study, therefore, was to translate, cross-culturally adapt, and evaluate the psychometric properties of the LAPS for the Brazilian population (LAPS-B). For this purpose, confirmatory factor analysis and reliability tests were conducted on a sample of 2526 dog and cat owners from all over the country, of whom 81.87% were female and who had a mean age of 33.85 years old (standard deviation = 12.81). The comparison between the models showed that the 3-factor correlated model and the hierarchical model had better metrics than the others, and that the hierarchical model was the most suitable. In conclusion, the Brazilian version of the LAPS is a reliable measure of the attachment to dogs or cats, and can be used to assist research and studies that address the human-animal relationship. Future research should investigate the psychometric properties of the scale on other animal species. [ABSTRACT FROM AUTHOR]

LAPS are field-effect-based potentiometric sensors which are able to monitor analyte concentrations in a spatially resolved manner. Hence, a LAPS sensor system is a powerful device to record chemical imaging of the concentration of chemical species in an aqueous solution, chemical reactions, or the growth of cell colonies on the sensor surface, to record chemical images. In this work, multi-chamber 3D-printed structures made out of polymer (PP-ABS) were combined with LAPS chips to analyse differentially and simultaneously the metabolic activity of Escherichia coli K12 and Chinese hamster ovary (CHO) cells, and the responds of those cells to the addition of glucose solution. [ABSTRACT FROM AUTHOR]

For higher photo signal of chemical image sensor, a new device structure of P-I-N amorphous silicon (a-Si) on ITO/glass is first applied in light-addressable potentiometric sensor (LAPS). Niobium oxide (NbO x ) is used as pH sensing membrane. All processes of device are lower than 300 o C, which are suitable for glass substrate. Based on photovoltage versus gate bias characteristics, calculated pH sensitivity and linearity between pH 2 to 10 is 40 mV/pH and 99.4%, respectively. Compare to conventional intrinsic amorphous silicon structure, improvement on photocurrent, and spatial resolution are 50% and 15%, respectively. In the meantime, higher frequency of ac signal of laser up to 20 kHz could be used for high speed scanning by means of red laser and analog micromirror scanning system. [ABSTRACT FROM AUTHOR]

LAPS are field-effect-based potentiometric sensors which are able to monitor analyte concentrations in a spatially resolved manner. Hence, a LAPS sensor system is a powerful device to record chemical imaging of the concentration of chemical species in an aqueous solution, chemical reactions, or the growth of cell colonies on the sensor surface, to record chemical images. In this work, multi-chamber 3D-printed structures made out of polymer (PP-ABS) were combined with LAPS chips to analyse differentially and simultaneously the metabolic activity of Escherichia coli K12 and Chinese hamster ovary (CHO) cells, and the responds of those cells to the addition of glucose solution. [ABSTRACT FROM AUTHOR]

For higher photo signal of chemical image sensor, a new device structure of P-I-N amorphous silicon (a-Si) on ITO/glass is first applied in light-addressable potentiometric sensor (LAPS). Niobium oxide (NbO x ) is used as pH sensing membrane. All processes of device are lower than 300 o C, which are suitable for glass substrate. Based on photovoltage versus gate bias characteristics, calculated pH sensitivity and linearity between pH 2 to 10 is 40 mV/pH and 99.4%, respectively. Compare to conventional intrinsic amorphous silicon structure, improvement on photocurrent, and spatial resolution are 50% and 15%, respectively. In the meantime, higher frequency of ac signal of laser up to 20 kHz could be used for high speed scanning by means of red laser and analog micromirror scanning system. [ABSTRACT FROM AUTHOR]

Light-addressable potentiometric sensors (LAPS) consisting of a p-Si-SiO2 and p-Si-SiO2-Au structure, respectively, have been tested for a label-free electrical detection of DNA (deoxyribonucleic acid) hybridization. Three different strategies for immobilizing single-stranded probe DNA (ssDNA) molecules on a LAPS surface have been studied and compared: (a) immobilization of thiol-modified ssDNA on the patterned Au surface via gold-thiol bond, (b) covalent immobilization of amino-modified ssDNA onto the SiO2 surface functionalized with 3-aminopropyltriethoxysilane and (c) layer-by-layer adsorption of negatively charged ssDNA on a positively charged weak polyelectrolyte layer of poly(allylamine hydrochloride). [ABSTRACT FROM AUTHOR]

Abstract: A new high throughput screening method to characterise alloys used as gate metal of Metal/solid Electrolyte/Insulator/Semiconductor (MEIS) gas-sensors was developed. Samples with continuous gradients in alloy concentration for the system Pd1-x-yNiyCoy were analysed regarding H2 sensitivity. First results showed reduced poisoning effects of H2S for Ni concentrations between 4-11 at-% in Pd. [Copyright &y& Elsevier]

Abstract: This work describes the novel combination of the light-addressable electrode (LAE) and the light-addressable potentiometric sensor (LAPS) into a microsystem set-up. Both the LAE as well as the LAPS shares the principle of addressing the active spot by means of a light beam. This enables both systems to manipulate resp. to detect an analyte with a high spatial resolution. Hence, combining both principles into a single set-up enables the active stimulation e.g., by means of electrolysis and a simultaneous observation e.g., the response of an entrapped biological cell by detection of extracellular pH changes. The work will describe the principles of both technologies and the necessary steps to integrate them into a single set-up. Furthermore, examples of application and operation of such systems will be presented. [Copyright &y& Elsevier]

Abstract: The integration of sensors in microfluidic systems is of special interest to build up lab-on-chip devices or micro-total-analysis-systems (μTAS). Those systems allow quick and cost-effective analysis with a minimum need of sample volumes. One drawback of present systems is the rigid sensor layout which has to be defined early during the design and the manufacturing of a new lab-on-chip system. This work will present the utilization of a light-addressable potentiometric sensor (LAPS) in combination with a microfluidic set-up, for the flexible adjustment of the size, the shape and the location of sensor spots at operation time. [Copyright &y& Elsevier]

Abstract: An analytical system for multicomponent analysis of liquids based on a light addressable potentiometric sensor (LAPS) with an array of ion-sensitive polymer membranes is presented. A developed LAPS device is based on a BESOI wafer which permits easy fabrication of a sensor with thin silicon membrane and enhanced spatial resolution. To generate the photocurrent the backside silicon was illuminated using a new technical approach based on a DLP (Digital Light Processing) chip used in video projectors. When a DLP chip is coordinated with a digital graphic signal, a light source, and a projection lens, its mirrors can reflect a digital image onto the LAPS surface. The developed system is shown to be able to produce light spots down to 50 μm in diameter and perform measurements at different points with programmable coordinates. To prove the functionality of the proposed method a LAPS sensor array with 60 ion-sensitive membranes of three different types was tested. [ABSTRACT FROM AUTHOR]

Abstract: Chemical imaging systems allow the visualisation of the distribution of chemical species on the sensor surface. This work represents a new flexible approach of read out in a light-addressable potentiometric sensor (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device which allows fast and flexible generation of light patterns. With the help of these light patterns the sensor surface of the LAPS device can be read out sequentially in a raster like scheme (scanning LAPS). The DLP approach has several advantages compared to conventional scanning LAPS set-ups, e.g., the spot size, the shape and the intensity of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of measurement. [ABSTRACT FROM AUTHOR]

Abstract: The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the two-dimensional distribution of specific ions or molecules in the solution. In this study, we developed a miniaturized chemical imaging sensor system with an OLED display panel as a light source that scans the sensor plate. In the proposed configuration, the display panel is placed directly below the sensor plate and illuminates the back surface. The measured area defined by illumination can be arbitrarily customized to fit the size and the shape of the sample to be measured. The waveform of the generated photocurrent, the currentvoltage characteristics and the pH sensitivity were investigated and pH imaging with this miniaturized system was demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: We herein propose and demonstrate the constant-phase-mode operation of the light-addressable potentiometric sensor (LAPS). The bias voltage applied to the LAPS sensor plate is servo-controlled to maintain the phase of the photocurrent with respect to the light modulation at a constant value. In this new operation mode, the temporal change and the spatial distribution of the potential at the sensing surface can be recorded and converted into the analyte concentration. This LAPS with a constant-phasemode is advantageous due to its wider measurement range and reduction of artifacts. [Copyright &y& Elsevier]

Abstract: A new LAPS (light-addressable potentiometric sensor) set-up will be introduced, in which the light sources are miniaturised by the utilisation of a VCSEL (vertical-cavity surface-emitting laser) array to increase the measurement spot density. An FPGA (field-programmable gate array) is used to generate modulation signals for an individual illumination of each measurement spot of the LAPS. The new set-up can operate a large number of measurement spots simultaneously by reading out the sum-photocurrent and separate the signals of the individual measurement spots by FFT analysis. The frequency, amplitude and offset of the modulation signal can be configured for each measurement spot programmatically. [Copyright &y& Elsevier]