A Digitally Programmable Active-RC Filter for On-Chip Portable Sensor Applications

An enhanced digital tuning approach for RC-active circuits is presented. Simulations of a 12-bit CMOS second-order filter provide a 11.46-bit effective resolution to linearly control the frequency over three decades with THD<-70 dB. Its low power, 0.5 mW, and low active area, 0.087 mm2, prove its suitability for on-chip sensing systems

Circuito de acondicionado CMOS para la monitorización de cultivos celulares

Este trabajo presenta la etapa de lectura de un front-end analógico para la monitorización del crecimiento de un cultivo celular mediante la medida de su impedancia. Basado en tecnología CMOS, su consumo es de 4.8 μW, proporcionando errores en recuperación del 1.7 % en magnitud y 3.7 % en fase

Analyzing the role of resilience and life satisfaction as mediators of the impact of COVID-19 worries on mental health

The aim of this study was to test whether resilience and life satisfaction (two traditional protective factors) mediate between COVID‐19 related worries and the development of symptoms of depression, anxiety, and stress in adolescents and young adults. Participants involved 392 adolescents and young adults (70.20% female) aged between 12 and 25 years (M = 17.05 years, SD = 3.08). Participants completed the COVID‐19 related worries scale, the CD‐RISC to analyse resilience, the Satisfaction with Life Scale, and the Depression, Anxiety, and Stress Scales‐21 to study emotional symptoms. Descriptive analyses and Pearson correlations were conducted, together with a structural equation modeling testing a mediational model and multigroup invariance. Results show that resilience and life satisfaction play a mediating role in the relation between the COVID‐19 related worries and emotional symptoms (depression, anxiety, and stress). This study highlights the role of protective factors on adolescents' and young adults' emotional symptoms during the COVID‐19 pandemic

Circumventing Traditional Conditioning Protocols in Polymer Membrane-Based Ion-Selective Electrodes

Preparation of ion-selective electrodes (ISEs) often requires long and complicated conditioning protocols limiting their application as tools for in-field measurements. Herein, we eliminated the need for electrode conditioning by loading the membrane cocktail directly with primary ion solution. This proof of concept experiment was performed with iodide, silver, and sodium selective electrodes. The proposed methodology significantly shortened the preparation time of ISEs, yielding functional electrodes with submicromolar detection limits. Moreover, it is anticipated that this approach may form the basis for the development of miniaturized all-solid-state ion-selective electrodes for in situ measurements

Simplified Cost-Effective Preparation of High-Performance Ag-Pt Nanowire Motors

A simplified cost-effective template approach for preparing efficient gold-free bimetal Ag–Pt nanowire motors, where the silver segment is obtained by a partial removal of the silver sacrificial layer is described (see figure). The unusual behavior, reflecting the ‘active’ role of the Ag segment and the asymmetry of the catalytic surface provides the ultrafast motion of these nanomotors

Simplified Cost-Effective Preparation of High-Performance Ag-Pt Nanowire Motors

A simplified cost-effective template approach for preparing efficient gold-free bimetal Ag–Pt nanowire motors, where the silver segment is obtained by a partial removal of the silver sacrificial layer is described (see figure). The unusual behavior, reflecting the ‘active’ role of the Ag segment and the asymmetry of the catalytic surface provides the ultrafast motion of these nanomotors

A CMOS Quadrature Signal Generator for Impedance Spectroscopy Measurement Systems

A CMOS fully integrated quadrature signal generator for on-chip impedance spectroscopy (IS) applications is presented. Frequency can be digitally tuned from 5 to 350 kHz with 12-bit resolution. Power consumption is 0.77 mW and active area is 0.129 mm2. Its suitability for the target application is validated with a Randles test impedance cell modelling a protein.Se presenta un generador de señales en cuadratura CMOS completamente integrado para aplicaciones de espectroscopía de impedancia en chip. La frecuencia puede controlarse digitalmente entre 5 y 350 kHz con una resolución de 12 bits. El consumo de potencia es de 0.77 mW y el área activa es 0.129 mm2. Su idoneidad para la aplicación objetivo se valida con una impedancia de test (celda de Randles) que modela una proteina