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In this paper, a fully differential amplifier is proposed in a 1.8 V-0.18 μm CMOS (Complementary Metal-Oxide-Semiconductor) technology, which can accommodate both voltage (V-mode) and current (C-mode) inputs. Post-layout simulation results show a fixed gain amplifier exhibiting a 26 dB (V-mode)/89 dBΩ (C-mode) gain and a programmable gain amplifier featuring a 6–26 dB gain, overall yielding a 26.8–46.4 dB dB (V-mode)/89.6–109.2 dBΩ (C-mode) programmable gain range, with a 100 MHz bandwidth and a power and area consumption of 360.5 µW and 0.0177 mm2, respectively. This amplifier has been designed considering the constraints and specifications (including low voltage, low power, reduced noise and high common mode rejection ratio) for its use in an analogue Lock-in-based Frequency Response Analyser-Impedance Spectroscopy (FRA-IS) device. The proposed design introduces a novel fully differential open-loop structure based on a transconductance–transimpedance (TC-TI) topology for high performance applications with a broad programmable bandwidth. To compare this work, different figures of merit (FoMs) are introduced as well as a comparison table with other simulated and experimental results, reporting an overall better performance in terms of gain, frequency and power-area consumption. [ABSTRACT FROM AUTHOR]

The growing development of communication technologies has given rise to the Internet of Things, which has led to the emergence of new cities, smart grids, and smart buildings, and the development of energy generation using renewable sources, as well as the emergence of new electrical loads such as the electric car. These advances give rise to the need for new media devices with remote communication, and require a greater control and monitoring of the state of the electrical grid in order to verify its correct state, as well as the detection of faults or alterations that are occurring in it due to these new generation systems or new loads. These remote, unsupervised measurement devices require galvanic isolation to protect the measurement and communication system, so that even if there is a break in the isolation, the integrity of the measurement and communication system is maintained. In addition, as it is a device prepared for multipoint measurement, the cost of the probe must be contained. This article details the design, implementation, and validation of a low-cost remote isolated differential voltage probe. This probe is intended for monitoring at network supply points, as well as for the verification of the European standard EN 50160 as a means of detecting disturbances in network behaviour. Its characteristics as a differential and isolated probe provide it with the possibility of floating voltage averaging, guaranteeing the integrity of the electronics of the low-voltage probe, i.e., the digitalisation and communication system. The measurements collected are sent via an MQTT protocol, which makes the remote probe a device compatible with the Internet of Energy. For the validation of the probe, a full functional test is performed, including FFT spectral analysis to verify the compliance of the mains voltage with the aforementioned European standard EN 50160. [ABSTRACT FROM AUTHOR]

Experiences of regret associated with caring for patients with multiple sclerosis (MS) can affect medical decisions. A non-interventional study was conducted to assess the dimensionality and item characteristics of a battery including the Regret Intensity Scale (RIS-10) and 15 items evaluating common situations experienced by nurses in MS care. A total of 97 nurses were included. The RIS-10 showed good internal reliability and a unidimensional structure according to Mokken analysis. All-item homogeneity coefficients exceeded 0.30, whereas scalability for the overall RIS-10 was 0.66, indicating a strong scale. This battery showed adequate psychometric properties to evaluate regret among MS nurses. [ABSTRACT FROM AUTHOR]

Background: Nurse practitioners (NPs) play a critical role in the multidisciplinary management of patients with multiple sclerosis (MS). Neurologists´ behavioral characteristics have been associated with suboptimal clinical decisions. However, limited information is available on their impact among NPs involved in MS care. The aim of this study was to assess nurses´ therapeutic choices to understand behavioral factors influencing their decision making process. Methods: A non-interventional, cross-sectional, web-based study was conducted. NPs actively involved in the care of patients with MS were invited to participate in the study by the Spanish Society of Neurology Nursing. Participants answered questions regarding their standard practice and therapeutic management of seven simulated relapsing-remitting MS (RRMS) case scenarios. A behavioral battery was used to measure participants´ life satisfaction, mood, positive social behaviors, feeling of helpfulness, attitudes toward adoption of evidence-based innovations, occupational burnout, and healthcare-related regret. The outcome of interest was therapeutic inertia (TI), defined as the lack of treatment escalation when there is clinical and radiological evidence of disease activity. A score to quantify TI was created based on the number of simulated scenarios where treatment intensification was warranted. Results: Overall, 331 NPs were invited to participate, 130 initiated the study, and 96 (29%) completed the study. The mean age (SD) was 44.6 (9.8) years and 91.7% were female. Seventy-three participants (76.0%) felt their opinions had a significant influence on neurologists´ therapeutic decisions. Sixteen NPs (16.5%) showed severe emotional exhaustion related to work and 13 (13.5%) had depressive symptoms. The mean (SD) TI score was 0.97 (1.1). Fifty-six of NPs showed TI in at least one case scenario. Higher years of nursing experience (p = 0.014), feeling of helpfulness (p = 0.014), positive attitudes toward innovations (p = 0.046), and a higher intensity of care-related regret (p = 0.021) were associated with a lower risk of TI (adjusted R2 = 0.28). Burnout was associated with higher risk of TI (p = 0.001). Conclusions: Although NPs cannot prescribe MS treatments in Spain, their behavioral characteristics may influence the management of patients with RRMS. Continuing education and specific strategies for reducing occupational burnout may lead to better management skills and improve MS care. [ABSTRACT FROM AUTHOR]

This paper presents a low-cost high-efficiency solar energy harvesting system to power outdoor wireless sensor nodes. It is based on a Voltage Open Circuit (VOC) algorithm that estimates the open-circuit voltage by means of a multilayer perceptron neural network model trained using local experimental characterization data, which are acquired through a novel low cost characterization system incorporated into the deployed node. Both units--characterization and modelling--are controlled by the same low-cost microcontroller, providing a complete solution which can be understood as a virtual pilot cell, with identical characteristics to those of the specific small solar cell installed on the sensor node, that besides allows an easy adaptation to changes in the actual environmental conditions, panel aging, etc. Experimental comparison to a classical pilot panel based VOC algorithm show better efficiency under the same tested conditions. [ABSTRACT FROM AUTHOR]

This paper presents the implementation of a wearable wireless sensor network aimed at monitoring harmful gases in industrial environments. The proposed solution is based on a customized wearable sensor node using a low-power low-rate wireless personal area network (LR-WPAN) communications protocol, which as a first approach measures CO2 concentration, and employs different low power strategies for appropriate energy handling which is essential to achieving long battery life. These wearables nodes are connected to a deployed static network and a web-based application allows data storage, remote control and monitoring of the complete network. Therefore, a complete and versatile remote web application with a locally implemented decision-making system is accomplished, which allows early detection of hazardous situations for exposed workers. [ABSTRACT FROM AUTHOR]

The use of wireless sensor networks (WSN) for monitoring physical and chemical variables in large areas allows density and frequency measurements which have been unavailable to date in classical measurement systems. To fully take advantage of this technology in a particular application, besides an accurate design and selection of all the components involved in its operation, it is essential to dispose of reliable lifetime estimation prior to deployment. This paper presents an experimental approach to determine the actual lifetime of such battery-operated systems, making use of a custom WSN architecture, and for different batteries technologies. To render a reliable evaluation, the energy consumption of the sensor nodes under their different operation modes, in correlation with the battery characteristics and the voltage regulation system, is jointly considered. The result is a complete and practical lifetime model, whose appropriate performance has been validated in a real deployment scenario. [ABSTRACT FROM AUTHOR]

This paper proposes a battery-compatible electronic interface based on a general purpose lock-in amplifier (LIA) capable of recovering input signals up to the MHz range. The core is a novel ASIC fabricated in 1.8 V 0.18 μm CMOS technology, which contains a dual-phase analog lock-in amplifier consisting of carefully designed building blocks to allow configurability over a wide frequency range while maintaining low power consumption. It operates using square input signals. Hence, for battery-operated microcontrolled systems, where square reference and exciting signals can be generated by the embedded microcontroller, the system benefits from intrinsic advantages such as simplicity, versatility and reduction in power and size. Experimental results confirm the signal recovery capability with signal-to-noise power ratios down to -39 dB with relative errors below 0.07% up to 1 MHz. Furthermore, the system has been successfully tested measuring the response of a microcantilever-based resonant sensor, achieving similar results with better power-bandwidth trade-off compared to other LIAs based on commercial off-the-shelf (COTS) components and commercial LIA equipment. [ABSTRACT FROM AUTHOR]

This work presents two current-mode integrated circuits designed for sensor signal preprocessing in embedded systems. The proposed circuits have been designed to provide good signal transfer and fulfill their function, while minimizing the load effects due to building complex conditioning architectures. The processing architecture based on the proposed building blocks can be reconfigured through digital programmability. Thus, sensor useful range can be expanded, changes in the sensor operation can be compensated for and furthermore, undesirable effects such as device mismatching and undesired physical magnitudes sensor sensibilities are reduced. The circuits were integrated using a 0.35 μm standard CMOS process. Experimental measurements, load effects and a study of two different tuning strategies are presented. From these results, system performance is tested in an application which entails extending the linear range of a magneto-resistive sensor. Circuit area, average power consumption and programmability features allow these circuits to be included in embedded sensing systems as a part of the analogue conditioning components. [ABSTRACT FROM AUTHOR]

This paper presents the design and postlayout simulation results of a capacitor-less low dropout (LDO) regulator fully integrated in a low-cost standard 180 nm Complementary Metal-Oxide-Semiconductor (CMOS) technology which regulates the output voltage at 1.2 V from a 3.3 to 1.3 V battery over a −40 to 120 °C temperature range. To meet with the constraints of system-on-chip (SoC) battery-operated devices, ultralow power (Iq = 8.6 µA) and minimum area consumption (0.109 mm2) are maintained, including a reference voltage Vref = 0.4 V. It uses a high-gain dynamically biased folded-based error amplifier topology optimized for low-voltage operation that achieves an enhanced regulation-fast transient performance trade-off. [ABSTRACT FROM AUTHOR]

This paper presents a new approach based on the use of a Current Steering (CS) technique for the design of fully integrated Gm–C Low Pass Filters (LPF) with sub-Hz to kHz tunable cut-off frequencies and an enhanced power-area-dynamic range trade-off. The proposed approach has been experimentally validated by two different first-order single-ended LPFs designed in a 0.18 µm CMOS technology powered by a 1.0 V single supply: a folded-OTA based LPF and a mirrored-OTA based LPF. The first one exhibits a constant power consumption of 180 nW at 100 nA bias current with an active area of 0.00135 mm2 and a tunable cutoff frequency that spans over 4 orders of magnitude (~100 mHz–152 Hz @ CL = 50 pF) preserving dynamic figures greater than 78 dB. The second one exhibits a power consumption of 1.75 µW at 500 nA with an active area of 0.0137 mm2 and a tunable cutoff frequency that spans over 5 orders of magnitude (~80 mHz–~1.2 kHz @ CL = 50 pF) preserving a dynamic range greater than 73 dB. Compared with previously reported filters, this proposal is a competitive solution while satisfying the low-voltage low-power on-chip constraints, becoming a preferable choice for general-purpose reconfigurable front-end sensor interfaces. [ABSTRACT FROM AUTHOR]

This paper presents a fully integrated Gm–C low pass filter (LPF) based on a current steering Gm reduction-tuning technique, specifically designed to operate as the output stage of a SoC lock-in amplifier. To validate this proposal, a first-order and a second-order single-ended topology were integrated into a 1.8 V to 0.18 µm CMOS (Complementary Metal-Oxide-Semiconductor) process, showing experimentally a tuneable cutoff frequency that spanned five orders of magnitude, from tens of mHz to kHz, with a constant current consumption (below 3 µA/pole), compact size (<0.0140 mm2/pole), and a dynamic range better than 70 dB. Compared to state-of-the-art solutions, the proposed approach exhibited very competitive performances while simultaneously fully satisfying the demanding requirements of on-chip portable measurement systems in terms of highly efficient area and power. This is of special relevance, taking into account the current trend towards multichannel instruments to process sensor arrays, as the total area and power consumption will be proportional to the number of channels. [ABSTRACT FROM AUTHOR]

This paper presents a fully integrated 0.18 μm CMOS Low-Dropout (LDO) Voltage Regulator specifically designed to meet the stringent requirements of a battery-operated impedance spectrometry multichannel CMOS micro-instrument. The proposed LDO provides a regulated 1.8 V voltage from a 3.6 V to 1.94 V battery voltage over a −40 °C to 100 °C temperature range, with a compact topology (<0.10 mm2 area) and a constant quiescent current of only 7.45 μA with 99.985% current efficiency, achieving remarkable state-of-art Figures of Merit (FoMs) for the regulating–transient performance. Experimental measurements validate its suitability for the target application, paving the way towards the future achievement of a truly portable System on Chip (SoC) platform for impedance sensors. [ABSTRACT FROM AUTHOR]

This paper presents a low-power fully integrated quadrature signal generator for system-on-chip (SoC) impedance spectroscopy applications. It has been designed in a 0.18 μm-1.8 V CMOS technology as a self-contained oscillator, without the need for an external reference clock. The frequency can be digitally tuned from 10 to 345 kHz with 12-bit accuracy and a relative mean error below 1.7%, thus supporting a wide range of impedance sensing applications. The proposal is experimentally validated in two impedance spectrometry examples, achieving good magnitude and phase recovery results compared to the results obtained using a commercial LCR-meter. Besides the wide frequency tuning range, the proposed programmable oscillator features a total power consumption lower than 0.77 mW and an active area of 0.129 mm2, thus constituting a highly suitable choice as stimulation module for instrument-on-a-chip devices. [ABSTRACT FROM AUTHOR]

Disability accrual is mainly driven by progression independent of relapse activity, which is present even in early stages of relapsing-remitting multiple sclerosis (RRMS) and sometimes overlooked. This multicenter, non-interventional study evaluated whether patient-reported outcomes measures (PROMs) could capture disability in 189 early-stage RRMS patients (mean age: 36.1 ± 9.4 years, 71.4% female, mean disease duration: 1.4 ± 0.8 years, median EDSS: 1.0). The 9-Hole Peg Test (9-HPT), NeuroQoL Upper Extremity (NeuroQoL-UE), Timed 25-Foot Walk (T25-FW), Multiple Sclerosis Walking Scale (MSWS-12), Symbol Digit Modalities Test (SDMT), and Perceived Deficits Questionnaire (PDQ-5) were used to assess hand function, gait, and cognition, respectively. These functions were at least mildly affected in this early-stage population, finding significant correlations between PROMs and clinical assessments. PROMs could enable early-stage RRMS patients to communicate their perceived disability in different domains, assisting clinicians in disease monitoring and decision making., Competing Interests: The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: JM, NM, and RGB are employees of Roche Pharma Spain. SSM received payment for lecturing or travel expenses from Merck-Serono, Biogen, Sanofi-Genzyme, Roche, and Novartis. JMM has served on scientific advisory boards and/or has received speaking honoraria, research funding, and support to attend scientific meetings from Biogen, Merck, Novartis, Roche and Teva. JS has received speaking honoraria, compensation for consulting services and support to attend scientific meetings from Almirall, Bayer, Biogen, Merck, Novartis, Sanofi, Roche, and Teva. AA has received compensation for consulting services from Biogen, BMS, Sanofi, Roche, Janssen, and Novartis; and speaking honoraria from Biogen, BMS, Sanofi, Roche, Janssen, Merck, Almirall, and Novartis. ABC has received courses and honoraria for her participation as speaker/meeting moderator/symposia organizer from Alter, Almirall, Bayer, Bial, Biogen, Bristol-Myers-Squibb, Lilly, Merck-Serono, Mylan, Novartis, Roche, Sanofi-Genzyme, Teva, and UCB; and support to attend scientific meetings from Biogen, Bial, Merck-Serono, Novartis, Roche, Sanofi-Genzyme, and Teva. JLSM has received support to attend scientific meetings from Novartis, Merck, and Biogen; speaking honoraria from Biogen, Novartis, Sanofi, Merck, Almirall, Bayer, and Teva; and has participated in clinical trials from Biogen, Merck, and Roche. FJBH has received compensation for consulting services and speaking honoraria from Almirall, Biogen, Genzyme, Merck-Serono, Novartis, Roche, Sanofi, and Teva. CC has received compensation for consulting services, speaking honoraria and support to attend scientific meetings and courses from Merck, Teva, Sanofi-Genzyme, Novartis, Biogen, Roche, and Bristol-Myers-Squibb. LB has received compensation for consulting services, speaking honoraria and support to attend scientific meetings from Bayer, Celgene, Biogen, Genzyme, Merck, Novartis, Roche, Almirall, and Teva. JDGS has received compensation for consulting services and speaking honoraria from Biogen, Novartis, Merck, UCB, Sanofi-Genzyme, Roche, Almirall, and Teva. MCA has received compensation for consulting services from Genzyme, Roche, Novartis, Sanofi, and Biogen. LNC has received compensations from Sanofi-Genzyme, Merk, Biogen, and Roche. EA has received speaking honoraria from Roche, Novartis, Merck, Sanofi, and Biogen. MGR has received speaking honoraria from Biogen, Sanofi, Almirall, and Novartis. OC has participated in studies and has received speaking honoraria from Roche, Merck, Biogen, and Novartis. LGT has received speaking honoraria from Biogen, Novartis, Merck, Bayer, Sanofi-Genzyme, Almirall, Roche, and Teva. MH has participated in observational studies and has received compensation for consulting services and speaking honoraria from Roche, Merck, Sanofi, Biogen, Novartis, and Bayer. The rest of the authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2023.)

Background: Virtual reality (VR) has emerged as a promising treatment approach in rehabilitation for patients with multiple sclerosis (MS) due to its potential to increase patient motivation and rehabilitation adherence. One of the key features for rehabilitation adherence is patient satisfaction with the VR rehabilitation (VRR) program, and information on user satisfaction and not only effectiveness is required to systematically include VRR in routine clinical practice. Given that information on patient satisfaction with VRR is scarce, the primary objective of this study is to assess long-term patient satisfaction with a novel VRR program. This program has been specifically designed for MS patients by a multidisciplinary team of specialists, based on an effective conventional rehabilitation (CR) program. Secondarily, discomfort with VRR will be evaluated, and therapy adherence and changes in a variety of domains typically affected by MS will be compared between patients receiving VRR and patients receiving CR. Methods: In this prospective single-center 6-months follow-up study, 32 and 16 MS patients will receive VRR or CR, respectively. Patients will attend twice weekly rehabilitation sessions on site during 4 weeks, and they will continue with rehabilitation at home for five additional months. Satisfaction, assessed by the User Satisfaction Evaluation Questionnaire (USEQ), at 6 months of the VRR program initiation will be the primary outcome. Secondary outcomes include adherence, disability, spasms and spasticity, balance, fatigue, activities of daily living (ADLs), depression, anxiety, work status, cognition, demographic, and clinical characteristics (in the VRR and CR groups), and discomfort (in the VRR group). Outcome measures will be assessed at baseline, and at 1 and 6 months of rehabilitation initiation. Discussion: The study is intended to provide a better understanding of long-term patient satisfaction with a VRR program specifically designed for MS patients. Additionally, the study will provide information on long-term adherence, changes in motor symptoms, cognitive functions and patient-reported outcomes after the rehabilitation program. The results from this study will help to gather valuable knowledge on the use of rehabilitation with a new VR tool in MS patients., (Copyright © 2020 Meca-Lallana, Prefasi, Alabarcez, Hernández, García-Vaz, Portaña, Gomis, Téllez, García-Bernáldez, Mauriño, Medrano and Vázquez-Doce.)