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We fabricate and demonstrate a thermal-radiation far-infared light source with enhanced thermal radiation efficiency, particularly within the crucial 8--14 μm wavelength range, which is vital for various applications. The device utilizes a metallic nanotube array (MeNTA) meticulously fabricated on a silicon wafer using stainless-steel material through sputter deposition. The simulation with Finite-Difference Time-Domain (FDTD) approach reveals significant alterations to the blackbodyradiated far-infrared spectrum. Experimental validation via Fourier Transform Infrared (FTIR) measurements confirms a pronounced wavelength filtering effect, primarily centered at 10.2 μm. The device incorporating stainless steel MeNTA exhibits 1.4 times improvement in luminous efficiency, reaching 7.45 × 10−3, accompanied by a radiated power of 11.034 mW and 0.681 mW/mm2 radiated power per area. These outcomes suggest the potential for expanding the fabrication process with alternative geometries and periods to tailor specific infrared emissions, which enables suitable thermal emitters for biomedical applications.

In recent decades, the research of nano-structure devices (e.g., carbon nanotube and graphene) has experienced rapid growth. These materials have supreme electronic, thermal, optical and mechanical properties and have received widespread concern in different fields. It is worth noting that gate hysteresis behavior of field effect transistors can always be found in ambient conditions, which may influence the transmission appearance. Many researchers have put forward various views on this question. Here, we summarize and discuss the mechanisms behind hysteresis, different influencing factors and improvement methods which help decrease or eliminate unevenness and asymmetry.

Background Cardiovascular disease is the leading cause of morbidity and mortality in patients with end‐stage renal disease. Heart rhythm complexity analysis has been shown to be useful in predicting outcomes in various diseases; however, data on patients with end‐stage renal disease are limited. In this study, we analyzed the association between heart rhythm complexity and long‐term cardiovascular outcomes in patients with end‐stage renal disease receiving peritoneal dialysis. Methods and Results We prospectively enrolled 133 patients receiving peritoneal dialysis and analyzed linear heart rate variability and heart rhythm complexity variables including detrended fluctuation analysis (DFA) and multiscale entropy. The primary outcome was cardiovascular mortality, and the secondary outcome was the occurrence of major adverse cardiovascular events. After a median of 6.37 years of follow‐up, 21 patients (22%) died from cardiovascular causes. These patients had a significantly lower low‐frequency band of heart rate variability, low/high‐frequency band ratio, total power band of heart rate variability, heart rate turbulence slope, deceleration capacity, short‐term DFA (DFAα1); and multiscale entropy slopes 1 to 5, scale 5, area 1 to 5, and area 6 to 20 compared with the patients who did not die from cardiovascular causes. Time‐dependent receiver operating characteristic curve analysis showed that DFAα1 had the greatest discriminatory power for cardiovascular mortality (area under the curve: 0.763) and major adverse cardiovascular events (area under the curve: 0.730). The best cutoff value for DFAα1 was 0.98 to predict both cardiovascular mortality and major adverse cardiovascular events. Multivariate Cox regression analysis showed that DFAα1 (hazard ratio: 0.076; 95% CI, 0.016–0.366; P=0.001) and area 1 to 5 (hazard ratio: 0.645; 95% CI, 0.447–0.930; P=0.019) were significantly associated with cardiovascular mortality. Conclusions Heart rhythm complexity appears to be a promising noninvasive tool to predict long‐term cardiovascular outcomes in patients receiving peritoneal dialysis.

This article presents a new sensitivity-improved electrochemical measurement architecture for cardiovascular disease (CVD) diagnosis by detecting CVD biomarkers, S100 beta protein and C-reactive protein (CRP). The new architecture includes a design for a new electrochemical measurement set-up, which improves the reaction conditions of chemical and biological molecules and incorporates a newly biochip design. With the new architecture, electrochemical measurement experiments were undertaken. The results obtained are related to the research article entitled “Improving sensitivity of a miniaturized label-free electrochemical biosensor using zigzag electrodes” [1].

This article reviews optical biosensors and their integration with microfluidic channels. The integrated biosensors have the advantages of higher accuracy and sensitivity because they can simultaneously monitor two or more parameters. They can further incorporate many functionalities such as electrical control and signal readout monolithically in a single semiconductor chip, making them ideal candidates for point-of-care testing. In this article, we discuss the applications by specifically looking into point-of-care testing (POCT) using integrated optical sensors. The requirement and future perspective of integrated optical biosensors for POC is addressed.

The purpose of this study was to determine the antioxidant activity of the seed shells and kernels of Jatropha curcas L. The extracts obtained from five solutions (0%–95% ethanol) were tested and compared. Overall, the antioxidant capacity of seed shell extracts was higher than that of seed kernel extracts. The seed shell extract obtained using 95% ethanol exhibited the best antioxidant activity among the five solutions. The half-maximal inhibitory concentration (IC50) of 1,1-diphenyl-2-picrylhydrazyl and free radical scavenging ability of 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) were 13.63 ± 0.15 and 6.75 ± 0.51 μg/mL, respectively. The reduction ability and total phenol content were 95.14 ± 27.04 μg ascorbic acid equivalents/mg of extract and 536.33 ± 8.62 μg gallic acid equivalents/mg of extract, respectively. In in vitro cytotoxicity assays, solutions with less than 250 μg/mL of seed shell extract had no major cytotoxicity. The seed shell of Jatropha curcas L. can be used as an antioxidant material and has potential for biomedical applications.

This work demonstrates a printable blending material, i.e., reduced graphene oxide (RGO) mixed with poly(methyl methacrylate) (PMMA), for formaldehyde sensing. Based on experimental results, 2% RGO/10% PMMA is an optimal ratio for formaldehyde detection, which produced a 30.5% resistance variation in response to 1000 ppm formaldehyde and high selectivity compared to different volatile organic compounds (VOCs), humidity, CO, and NO. The demonstrated detection limit is 100 ppm with 1.51% resistance variation. Characterization of the developed formaldehyde sensing material was performed by Fourier-transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), and Raman spectroscopy. Based on Raman spectroscopy, the basic sensing mechanism is the band distortion of RGO due to blending with PMMA and the adsorption of formaldehyde. This work establishes insights into the formaldehyde sensing mechanism and explores a potential printable sensing material for diverse applications.

A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems.

Natural disasters such as typhoons, earthquakes, and especially floods, often cause severe damage in Taiwan. Although bridge engineering technology has matured, the lack of an integrated bridge management system under severe disasters remains a challenge for the government. This research aims to develop a web-based system that displays the real time bridge scour information through combining Global Positioning System and Wireless Sensor Networks technologies for bridges. The system also provides early warnings for bridge safety based on a developed genetic model for estimating scour depth around the bridge piers. The bridge safety monitoring agency utilizes the system as a decision support tool to make the maintenance plan for bridges and block the bridges under severe weather conditions to prevent the damages from bridge collapse.

A fully integrated humidity sensor chip was designed, implemented, and tested. Utilizing the micro-stamping technology, the pseudo-3D sensor system-on-chip (SSoC) architecture can be implemented by stacking sensing materials directly on the top of a CMOS-fabricated chip. The fabricated sensor system-on-chip (2.28 mm × 2.48 mm) integrated a humidity sensor, an interface circuit, a digital controller, and an On-Off Keying (OOK) wireless transceiver. With low power consumption, i.e., 750 μW without RF operation, the sensitivity of developed sensor chip was experimentally verified in the relative humidity (RH) range from 32% to 60%. The response time of the chip was also experimentally verified to be within 5 seconds from RH 36% to RH 64%. As a consequence, the implemented humidity SSoC paves the way toward the an ultra-small sensor system for various applications.

Wireless Sensor Network (WSN) technology is currently being employed in the field of civil engineering, especially in the areas of structural monitoring and construction safety. When used in construction site safety, time-synchronization within the sensor network is required to obtain important correlations between events, such as the prevention of equipment collisions. Here, we develop a highly efficient time synchronization method for an ultra-precise localization system to prevent collision accidents at construction sites. Without interfering with the operation of the entire sensor network, the developed protocol can locally synchronize several nodes within 10 ms. By measuring the time uncertainty information through the time stamping, wireless sensor nodes can be synchronized with only two transmitted packages from the beacon or specific nodes. Based on this proposed approach, 0.8 micro-second synchronization error was experimentally achieved on an IEEE 802.15.4 platform. Employing the developed method, the localization system was implemented and experimentally examined to have accuracy within several centimeters in the range of 2 m. This localization system can be used to identify the location of different construction equipment. This work demonstrates a simple and efficient approach to obtain high accuracy, low communication overhead, and robust synchronization for most WSN platforms to be used in automated monitoring at construction sites.

Automation technologies are extensively adopted in the fields of mechanics and manufacture. Thanks to continuous progress in scientific development, automation has been used increasingly in civil structures and structural monitoring. Through the interview of the director of NCREE, Dr. Kuo-Chun Chang, we hope that readers can examine the future developments and limits of automation technology on application in the field of civil engineering.

Statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, are used to reduce cholesterol biosynthesis in the liver. Accordingly, statins regulate nitric oxide (NO) and glutamate metabolism, inflammation, angiogenesis, immunity and endothelial progenitor cells (EPCs) functions. The function of EPCs are regulated by stromal cell-derived factor 1 (SDF-1), vascular endothelial growth factor (VEGF), and transforming growth factor β (TGF-β), etc. Even though the pharmacologic mechanisms by which statins affect the neovasculogenesis of circulating EPCs, it is still unknown whether statins affect the EPCs function through the regulation of CXCR4, a SDF-1 receptor expression. Therefore, we desired to explore the effects of statins on CXCR4 expression in EPC-mediated neovascularization by in vitro and in vivo analyses. In animal studies, we analyzed the effects of atorvastatin or rosuvastatin treatments in recovery of capillary density and blood flow, the expression of vWF and CXCR4 at ischemia sites in hindlimb ischemia ICR mice. Additionally, we analyzed whether the atorvastatin or rosuvastatin treatments increased the mobilization, homing, and CXCR4 expression of EPCs in hindlimb ischemia ICR mice that underwent bone marrow transplantation. The results indicated that statins treatment led to significantly more CXCR4-positive endothelial progenitor cells incorporated into ischemic sites and in the blood compared with control mice. In vivo, we isolated human EPCs and analyzed the effect of statins treatment on the vasculogenic ability of EPCs and the expression of CXCR4. Compared with the control groups, the neovascularization ability of EPCs was significantly improved in the atorvastatin or rosuvastatin group; this improvement was dependent on CXCR4 up-regulation. The efficacy of statins on improving EPC neovascularization was related to the SDF-1α/CXCR4 axis and might be regulated by the NO. In conclusion, atorvastatin and rosuvastatin improved neovascularization in hindlimb ischemia mice; this effect may have been mediated by increased CXCR4 expression in EPCs.

Coronary artery disease and its related complications pose great threats to human health. In this work, we aim to clinically evaluate a CMOS field-effect biomolecular sensor for cardiac biomarkers, cardiac-specific troponin-I (cTnI), N-terminal prohormone brain natriuretic peptide (NT-proBNP), and interleukin-6 (IL-6). The CMOS biosensor is implemented via a standard commercialized 0.35 μm CMOS process. To validate the sensing characteristics, in buffer conditions, the developed CMOS biosensor has identified the detection limits of IL-6, cTnI, and NT-proBNP as being 45 pM, 32 pM, and 32 pM, respectively. In clinical serum conditions, furthermore, the developed CMOS biosensor performs a good correlation with an enzyme-linked immuno-sorbent assay (ELISA) obtained from a hospital central laboratory. Based on this work, the CMOS field-effect biosensor poses good potential for accomplishing the needs of a point-of-care testing (POCT) system for heart disease diagnosis.

A self-sustained multi-sensor platform for indoor environmental monitoring is proposed in this paper. To reduce the cost and power consumption of the sensing platform, in the developed platform, organic materials of PEDOT:PSS and PEDOT:PSS/EB-PANI are used as the sensing films for humidity and CO2 detection, respectively. Different from traditional gas sensors, these organic sensing films can operate at room temperature without heating processes or infrared transceivers so that the power consumption of the developed humidity and the CO2 sensors can be as low as 10 μW and 5 μW, respectively. To cooperate with these low-power sensors, a Complementary Metal-Oxide-Semiconductor (CMOS) system-on-chip (SoC) is designed to amplify and to read out multiple sensor signals with low power consumption. The developed SoC includes an analog-front-end interface circuit (AFE), an analog-to-digital convertor (ADC), a digital controller and a power management unit (PMU). Scheduled by the digital controller, the sensing circuits are power gated with a small duty-cycle to reduce the average power consumption to 3.2 μW. The designed PMU converts the power scavenged from a dye sensitized solar cell (DSSC) module into required supply voltages for SoC circuits operation under typical indoor illuminance conditions. To our knowledge, this is the first multiple environmental parameters (Temperature/CO2/Humidity) sensing platform that demonstrates a true self-powering functionality for long-term operations.

To improve the field-effect mobility of all-inkjet-printed organic thin film transistors (OTFTs), a composite material consisted of carbon nanoparticles (CNPs) and poly(3-hexylthiophene) (P3HT) was reported by using homemade inkjet-printing system. These all-inkjet-printed composite OTFTs represented superior characteristics compared to the all-inkjet-printed pristine P3HT OTFTs. To investigate the enhancement mechanism of the blended materials, the percolation model was established and experimentally verified to illustrate the enhancement of the electrical properties with different blending concentrations. In addition, experimental results of OTFT contact resistances showed that both contact resistance and channel resistance were halved. At the same time, X-ray diffraction measurements, Fourier transform infrared spectra, ultraviolet-visible light, and photoluminescence spectra were also accomplished to clarify the material blending effects. Therefore, this study demonstrates the potential and guideline of carbon-based nanocomposite materials in all-inkjet-printed organic electronics.

Poly(3-hexylthiophene), P3HT, has been widely used in organic electronics as a semiconductor material. It suffers from the low carrier mobility characteristics. This limits P3HT to be employed in applications. Therefore, the blending semiconductor material, carbon nanoparticle (CNP), and P3HT, are developed and examined by inkjet-printing organic field-effect transistor technology in this work. The effective carrier mobility of fabricated OFETs can be enhanced by 8 folds with adding CNP and using O2 plasma treatment. At the same time, the transconductance of fabricated OFETs is also raised by 5 folds. Based on the observations of SEM, XRD, and FTIR, these improvements are contributed to the local field induced by the formation of CNP/P3HT complexes. This observation presents an insight of the development in organic semiconductor materials. Moreover, this work also offers a low-cost and effective semiconductor material for inkjet-printing technology in the development of organic electronics.