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Inclusive Healthcare Waiting Rooms: A Comparison Study for Improving the User Experience Within Built Environment
No full textThe role of the built environment in the context of healthcare service highly impacts how human interactions take place. However, when an environment has already been built not respecting accessibility features, future actions are going to be more expensive and often ineffective. Accessibility legislation in Mexico was published after many healthcare buildings were built. Moreover, there is some evidence that government standards fail short to ensure Inclusive Design. This study aims to compare Mexican building regulations with internationally approved standards and, to analyze if they are applied to the design of an existing waiting room of a neurology outpatient unit. A comparison between international and national standards, and a physical audit of the waiting room were performed. Results suggest that even if the waiting room was built according to updated official regulations, there would be still more room for further improvement in order to satisfy stakeholders needs fully
Photo-rechargeable Zinc-Ion Capacitors using V<inf>2</inf>O<inf>5</inf>-Activated Carbon Electrodes
No full textElectrochemical energy storage devices that can harvest energy from the environment and store it are increasingly important to address energy poverty in developing parts of the world as well as powering off-grid autonomous devices. Currently, batteries or supercapacitors connected to solar cells are used for these applications, but these frequently suffer from voltage mismatches and inefficiencies in the device packaging. This paper presents an optically and electrochemically active electrode for photo-rechargeable zinc-ion capacitors using vanadium oxide nanofibers. These rely on photoexcited charge carrier separation to charge the capacitors without any external photovoltaic or electrical devices. We found that silver nanowires are better than carbon-based conductive additives as they support photoexcited hole transport and provide light scattering centers that enhance visible light absorption. The proposed capacitors show a ∼63% capacity increase under illumination, photorecharge in 30 min, and ∼99% capacity retention over 4000 cycles
Fabrication and Characterization of Partially Conjugated Poly (Vinyl Alcohol) Based Resistive Humidity Sensor
No full textHumidity sensors have been developed based on a wide variety of materials such as ceramic, semiconductors and polymers. However, slow recovery rates is one of the major ongoing concerns of flexible poly(vinyl alcohol) (PVA) based humidity sensors. In this study, a simple, cost effective, fast responding, fast recovering and high sensitive, resistive poly(vinyl alcohol) (PVA) based humidity sensor was developed through the development of controlled conjugation system in PVA polymer matrix by hydroiodic acid (HI) treatment. Changes in structural and morphological parameters on sensor performance were investigated. Resistance of the sensor increased from 10.2 kΩ to 4.5 MΩ when relative humidity (RH) decreased from 92% to 7% RH, while capacitance varied slightly from 70 nF to 100 nF. The response and recovery times of the sensor were measured to be 224.6 s and 56.3 s respectively at room temperature when switching between 50% and 90% RH, demonstrating excellent performance towards fluctuating humidity levels. The results indicate the sensor is capable of measuring humidity levels above 30% with full scale recovery by only consuming 25% of the sensing time. Cost-effective, flexible, fast recovery and resistive sensing can be recognized as the most effective potential applications for this sensor
A Silicon Photonic Switching Platform for Flexible Converged Centralized-Radio Access Networking
No full textUnprecedented levels of device connectivity and the emergence of futuristic digital services are driving fundamental changes to underlying fixed and wireless data transport networks. Projected bandwidth requirements, coupled with increased network centralization and virtualization, will lead to the convergence of data-center, fixed and wireless systems, and a greater onus being placed on the optical routing/transport portion of these networks. Such converged networks will require the development of optical technologies capable of servicing a multitude of network user types. In this work, we propose the use of a Silicon Photonic (SiP) space-and-wavelength selective switch fabric as a flexible wavelength provisioning platform for converged optical networks. The envisaged converged network is presented and an experimental test-bed which demonstrates flexible Cloud Radio Access Networking (C-RAN), using a 4 × 4 micro-ring resonator based switch, is described. Successful provisioning and transmission of Wavelength Division Multiplexed (WDM) based analog Radio-over-Fiber (RoF) services, over 10 km of fiber, in the converged test-bed is demonstrated and evaluated in terms of the received Bit Error Rate (BER) and Error Vector Magnitude (EVM). Furthermore, the wavelength multi-casting capabilities of the SiP switch is shown to enable dynamic resource allocation in the optical domain, and this is highlighted through the experimental implementation and evaluation of two C-RAN use cases - representing high and low mobile traffic demand scenarios
M2 macrophage-derived exosomes promote the c-KIT phenotype of vascular smooth muscle cells during vascular tissue repair after intravascular stent implantation
No full textRationale: For intravascular stent implantation to be successful, the processes of vascular tissue repair and therapy are considered to be critical. However, the mechanisms underlying the eventual fate of vascular smooth muscle cells (VSMCs) during vascular tissue repair remains elusive. In this study, we hypothesized that M2 macrophage-derived exosomes to mediate cell-to-cell crosstalk and induce dedifferentiation phenotypes in VSMCs. Methods: In vivo, 316L bare metal stents (BMS) were implanted from the left iliac artery into the abdominal aorta of 12-week-old male Sprague-Dawley (SD) rats for 7 and 28 days. Hematoxylin and eosin (HE) were used to stain the neointimal lesions. En-face immunofluorescence staining of smooth muscle 22 alpha (SM22α) and CD68 showed the rat aorta smooth muscle cells (RASMCs) and macrophages. Immunohistochemical staining of total galactose-specific lectin 3 (MAC-2) and total chitinase 3-like 3 (YM-1) showed the total macrophages and M2 macrophages. In vitro, exosomes derived from IL-413-treated macrophages (M2Es) were isolated by ultracentrifugation and characterized based on their specific morphology. Ki-67 staining was conducted to assess the effects of the M2Es on the proliferation of RASMCs. An atomic force microscope (AFM) was used to detect the stiffness of the VSMCs. GW4869 was used to inhibit exosome release. RNA-seq was performed to determine the mRNA profiles of the RASMCs and M2Es-treated RASMCs. Quantitative real-time PCR (qRT-PCR) analysis was conducted to detect the expression levels of the mRNAs. Western blotting was used to detect the candidate protein expression levels. T-5224 was used to inhibit the DNA binding activity of AP-1 in RASMCs. Results: M2Es promote c-KIT expression and softening of nearby VSMCs, hence accelerating the vascular tissue repair process. VSMCs co-cultured in vitro with M2 macrophages presented an increased capacity for de-differentiation and softening, which was exosome dependent. In addition, the isolated M2Es helped to promote VSMC dedifferentiation and softening. Furthermore, the M2Es enhanced vascular tissue repair potency by upregulation of VSMCs c-KIT expression via activation of the c-Jun/activator protein 1 (AP-1) signaling pathway. Conclusions: The findings of this study emphasize the prominent role of M2Es during VSMC dedifferentiation and vascular tissue repair via activation of the c-Jun/AP-1 signaling pathway, which has a profound impact on the therapeutic strategies of coronary stenting techniques
Passive dielectrophoretic focusing of particles and cells in ratchet microchannels
No full textFocusing particles into a tight stream is critical for many microfluidic particle-handling devices such as flow cytometers and particle sorters. This work presents a fundamental study of the passive focusing of polystyrene particles in ratchet microchannels via direct current dielectrophoresis (DC DEP). We demonstrate using both experiments and simulation that particles achieve better focusing in a symmetric ratchet microchannel than in an asymmetric one, regardless of the particle movement direction in the latter. The particle focusing ratio, which is defined as the microchannel width over the particle stream width, is found to increase with an increase in particle size or electric field in the symmetric ratchet microchannel. Moreover, it exhibits an almost linear correlation with the number of ratchets, which can be explained by a theoretical formula that is obtained from a scaling analysis. In addition, we have demonstrated a DC dielectrophoretic focusing of yeast cells in the symmetric ratchet microchannel with minimal impact on the cell viability
Characterizing Maturity Levels for Organization-Wide Roadmapping Implementation
No full textImplementing roadmapping guides improved strategy development for organizations not only to produce new products or services but also to navigate the entire process of organizational capability development to accelerate innovation. However, keeping roadmapping alive in organizations is challenging due to the complex integration process with a broad range of stakeholder involvement. While previous studies have contributed to staged development for managing roadmapping implementation, relatively little attention has been given to practical steps required in each stage for organizations to review the past, understand the current position in terms of where they are up to, and plan for the future to navigate the complex integration process efficiently and effectively. This article introduces a maturity model to guide the process of organization-wide roadmapping implementation. This is achieved by examining industrial cases to characterize practical steps, from the perspective of maturation, by which organizations implement and eventually integrate roadmapping into the organizational system and business cycles for technology and strategic planning. The Gerdsri three-stage model was utilized for discussion and analysis, aligning with the maturity model development. Six maturity levels have been characterized as follows: 1) Initial; 2) Defined; 3) Rolled Out; 4) Developed; 5) Standardized; and 6) Sustained
Assessing the acceptability of a text messaging service and smartphone app to support patient adherence to medications prescribed for high blood pressure: A pilot study
No full textAims and objectives: This paper describes a pilot non-randomised controlled study of a highly tailored 56-day text messaging and smartphone app prototype intervention to increase adherence to anti-hypertensive medication in primary care. The aim of this study was to evaluate the acceptability of the intervention and obtain patients' views about the intervention content, the delivery mode, and the mechanisms by which the intervention supported medication adherence. Methods: Patients diagnosed with hypertension were invited and recruited to the study via general practice text messages and attended a face to face meeting with a member of the researcher team. Participants were asked to test the text messaging intervention for 28 consecutive days and switch to the smartphone app for 28 more days. Participants completed baseline and follow-up questionnaires and took part in semi-structured telephone interviews. Digital log files captured patients' engagement with the intervention. Participant transcripts were analysed using thematic analysis. Descriptive statistics were used to summarise data from questionnaires and log files. A mixed methods analysis generated data to respond to the research questions. Results: Seventy-nine patients expressed interest to participate in this study, of whom 23 (64% male, 82% above 60 years old) were registered to take part. With one drop-out, 22 participants tested the text messaging delivery mode (with 20 being interviewed) and four of them (17%) switched to the app (with 3 being interviewed). All participants engaged and interacted with the text messages and app notifications, and all participants found the intervention content and delivery mode acceptable. They also self-reported that the interactive elements of the intervention motivated them to take their medications as prescribed. Conclusion: This study provides evidence that the digital intervention is acceptable by hypertensive patients recruited in primary care. Future research could usefully investigate its feasibility and effectiveness using rigorous research methods. Trial registration: ISRCTN1280565
Quantifying wind-induced impacts on particulate Cu footprint in the Yangtze Estuary.
No full textUnder two wind conditions, a polar coordinated segmented quantification method (PCSQM) taking the easternmost point of Chongming Island (121°59'20″E, 31°29'38″N) as the origin of the coordinate was proposed to quantify wind-induced impacts on the heavy metal footprint emitted from four simulation sites on the main waterway of the Yangtze Estuary. One wind condition was that of a real wind field in 2019 called Case 1; the other one was a combination of monthly maximum wind speed selected from 1989 to 2019 called Case 2. In the comparison of these two conditions, the PCSQM was used to calculate the footprint excursion of four simulation sites mentioned, including three major urban sewage outlets and the upstream pollution source, represented by Xuliujing (XLJ) during the biological sensitive aggregation period of the Yangtze Estuary (BAPYE). The results showed that the Cu footprint was closer to Chongming Island and showed a trend of narrowing its coverage under Case2 compared with Case1. The Southeast section of the XLJ had the broadest width (83.46 km), while the Southwestern section of BLG had the narrowest width (3.52 km). Coincidentally, both the maximum (-29.99%) and the minimum excursion (-0.13%) were derived from XLJ, corresponding to its Southeast section and Southwest section
A Mismatch Calibration Technique for SAR ADCs Based on Deterministic Self-Calibration and Stochastic Quantization
No full textA capacitive DAC is an important building block of a charge-redistribution SAR ADC, for its size has a significant impact on performance. For medium- to high-resolution applications, the size of the DAC is typically determined by random mismatches. As such, an effective mismatch calibration circuit can allow the DAC to be scaled down to a much lower kT/C noise limit, thereby increasing the overall ADC power efficiency. This paper reviews some of the most important reported mismatch calibration techniques and proposes a foreground calibration method based on a deterministic self-calibration and stochastic quantization. This approach is experimentally validated on a prototype 10-bit SAR ADC fabricated in TSMC 28-nm LP CMOS technology, demonstrating an INL and SFDR improvement of respectively 6.4 LSB and 14.9 dB at 85 MS/s