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This article presents a high-frequency application-specific integrated circuit (ASIC) transceiver for an ultrasound imaging system designed with a focus on low complexity. To simplify the design, it employs a conventional Class-D power amplifier structure for the transmitter (TX) and a resistive feedback transimpedance amplifier (TIA), which consists of a common-source amplifier followed by a source follower for the receiver (RX). Through careful optimization, the RX achieves a measured transimpedance gain of 90 dBΩ and an input-referred noise of 5.6 pA/√Hz at 30 MHz while maintaining a wide bandwidth of up to 30 MHz for both the TX and RX. The power consumption of the TX and RX is measured to be 7.767 mW and 2.5 mW, respectively. Further acoustic performance, assessed using an annular capacitive micromachined ultrasonic transducer (CMUT), showed a 1.78 kPa peak pressure from a 20 V pulser and confirmed the full bandwidth compatibility of the CMUT's bandwidth. The ASIC transceiver has been fabricated using a 0.18 μm HV bipolar-CMOS-DMOS (BCD) process. [ABSTRACT FROM AUTHOR]

Introduction: Recent studies have investigated the autonomic modulation method using closed-loop vibration stimulation (CLVS) as a novel strategy for enhancing sleep quality. This study aimed to explore the effects of CLVS on sleep quality, autonomic regulation, and brain activity in individuals with poor sleep quality. Methods: Twenty-seven participants with poor sleep quality (Pittsburgh sleep quality index >5) underwent two experimental sessions using polysomnography and a questionnaire, one with CLVS (STIM) and the other without (SHAM). Results: Sleep macrostructure analysis first showed that CLVS significantly reduced the total time, proportion, and average duration of waking after sleep onset. These beneficial effects were paralleled by significantly increased self-reported sleep quality. Moreover, there was a significant increase in the normalized high-frequency (nHF) and electroencephalography relative powers of delta activity during N3 sleep under STIM. Additionally, coherence analysis between nHF and delta activity revealed strengthened coupling between cortical and cardiac oscillations. Discussion: This study demonstrated that CLVS significantly improves sleep quality in individuals with poor sleep quality by enhancing both subjective and objective measures. These findings suggest that CLVS has the potential to be a practical, noninvasive tool for enhancing sleep quality in individuals with sleep disturbances, offering an effective alternative to pharmacological treatments. [ABSTRACT FROM AUTHOR]

Wireless modules that provide telecommunications and power-harvesting capabilities enabled by radio-frequency (RF) electronics are vital components of skin-interfaced stretchable electronics1–7. However, recent studies on stretchable RF components have demonstrated that substantial changes in electrical properties, such as a shift in the antenna resonance frequency, occur even under relatively low elastic strains8–15. Such changes lead directly to greatly reduced wireless signal strength or power-transfer efficiency in stretchable systems, particularly in physically dynamic environments such as the surface of the skin. Here we present strain-invariant stretchable RF electronics capable of completely maintaining the original RF properties under various elastic strains using a ‘dielectro-elastic’ material as the substrate. Dielectro-elastic materials have physically tunable dielectric properties that effectively avert frequency shifts arising in interfacing RF electronics. Compared with conventional stretchable substrate materials, our material has superior electrical, mechanical and thermal properties that are suitable for high-performance stretchable RF electronics. In this paper, we describe the materials, fabrication and design strategies that serve as the foundation for enabling the strain-invariant behaviour of key RF components based on experimental and computational studies. Finally, we present a set of skin-interfaced wireless healthcare monitors based on strain-invariant stretchable RF electronics with a wireless operational distance of up to 30 m under strain.Stretchable radio-frequency electronics based on a dielectro-elastic elastomer is demonstrated to be capable of completely maintaining operating frequencies unaffected by strain and shows superior electrical, mechanical and thermal properties compared with conventional stretchable substrate materials. [ABSTRACT FROM AUTHOR]

High-fat diet-induced obesity is a pandemic caused by an inactive lifestyle and increased consumption of Western diets and is a major risk factor for diabetes and cardiovascular diseases. In contrast, exercise can positively influence gut microbial diversity and is linked to a decreased inflammatory state. To understand the gut microbial variations associated with exercise and high-fat diet over time, we conducted a longitudinal study to examine the effect of covariates on gut microbial diversity and composition. Young mice were divided into four groups: Chow-diet (CHD), high-fat diet (HFD), high-fat diet + exercise (HFX), and exercise only (EXE) and underwent experimental intervention for 12 weeks. Fecal samples at week 0 and 12 were collected for DNA extraction, followed by 16S library preparation and sequencing. Data were analyzed using QIIME 2, R and MicrobiomeAnalyst. The Bacteroidetes-to-Firmicutes ratio decreased fivefold in the HFD and HFX groups compared to that in the CHD and EXE groups and increased in the EXE group over time. Alpha diversity was significantly increased in the EXE group longitudinally (p < 0.02), whereas diversity (Shannon, Faith's PD, and Fisher) and richness (ACE) was significantly reduced in the HFD (p < 0.005) and HFX (p < 0.03) groups over time. Beta diversity, based on the Jaccard, Bray–Curtis, and unweighted UniFrac distance metrics, was significant among the groups. Prevotella, Paraprevotella, Candidatus arthromitus, Lactobacillus salivarius, L. reuteri, Roseburia, Bacteroides uniformis, Sutterella, and Corynebacterium were differentially abundant in the chow-diet groups (CHD and EXE). Exercise significantly reduced the proportion of taxa characteristic of a high-fat diet, including Butyricimonas, Ruminococcus gnavus, and Mucispirillum schaedleri. Diet, age, and exercise significantly contributed to explaining the bacterial community structure and diversity in the gut microbiota. Modulating the gut microbiota and maintaining its stability can lead to targeted microbiome therapies to manage chronic and recurrent diseases and infections. [ABSTRACT FROM AUTHOR]

Inhalation of ambient particulate matter (PM) can disrupt the gut microbiome, while exercise independently influences the gut microbiome by promoting beneficial bacteria. In this study, we analyzed changes in gut microbial diversity and composition in response to combined interventions of PM exposure and aerobic exercise, extending up to 12 weeks. This investigation was conducted using mice, categorized into five groups: control group (Con), exercise group (EXE), exercise group followed by 3-day exposure to PM (EXE + 3-day PM), particulate matter exposure (PM), and PM exposure with concurrent treadmill exercise (PME). Notably, the PM group exhibited markedly lower alpha diversity and richness compared to the Con group and our analysis of beta diversity revealed significant variations among the intervention groups. Members of the Lachnospiraceae family showed significant enhancement in the exercise intervention groups (EXE and PME) compared to the Con and PM groups. The biomarker Lactobacillus, Coriobacteraceae, and Anaerofustis were enriched in the EXE group, while Desulfovibrionaceae, Mucispirillum schaedleri, Lactococcus and Anaeroplasma were highly enriched in the PM group. Differential abundance analysis revealed that Paraprevotella, Bacteroides, and Blautia were less abundant in the 12-week PM exposure group than in the 3-day PM exposure group. Moreover, both the 3-day and 12-week PM exposure groups exhibited a reduced relative abundance of Bacteroides uniformis, SMB53, and Staphylococcus compared to non-PM exposure groups. These findings will help delineate the possible roles and associations of altered microbiota resulting from the studied interventions, paving the way for future mechanistic research. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) has deleterious consequences not only on the respiratory system but also on essential human organs, such as the heart, blood vessels, kidneys, and liver. However, the effects of PM inhalation on skeletal muscles have yet to be sufficiently elucidated. Female C57BL/6 or mt-Keima transgenic mice were randomly assigned to one of the following four groups: control (CON), PM exposure alone (PM), treadmill exercise (EX), or PM exposure and exercise (PME). Mice in the three-treatment group were subjected to treadmill running (20 m/min, 90 min/day for 1 week) and/or exposure to PM (100 μg/m3). The PM was found to exacerbate oxidative stress and inflammation, both at rest and during exercise, as assessed by the levels of proinflammatory cytokines, manganese-superoxide dismutase activity, and the glutathione/oxidized glutathione ratio. Furthermore, we detected significant increases in the levels of in vivo mitophagy, particularly in the PM group. Compared with the EX group, a significant reduction in the level of mitochondrial DNA was recorded in the PME group. Moreover, PM resulted in a reduction in cytochrome c oxidase activity and an increase in hydrogen peroxide generation. However, exposure to PM had no significant effect on mitochondrial respiration. Collectively, our findings in this study indicate that PM has adverse effects concerning both oxidative stress and inflammatory responses in skeletal muscle and mitochondria, both at rest and during exercise. [ABSTRACT FROM AUTHOR]

With the rapid increase in the number of cyber-attacks, detecting and preventing malicious behavior has become more important than ever before. In this study, we propose a method for detecting and classifying malicious behavior in host process data using machine learning algorithms. One of the challenges in this study is dealing with high-dimensional and imbalanced data. To address this, we first preprocessed the data using Principal Component Analysis (PCA) and Uniform Manifold Approximation and Projection (UMAP) to reduce the dimensions of the data and visualize the distribution. We then used the Adaptive Synthetic (ADASYN) and Synthetic Minority Over-sampling Technique (SMOTE) to handle the imbalanced data. We trained and evaluated the performance of the models using various machine learning algorithms, such as K-Nearest Neighbor, Naive Bayes, Random Forest, Autoencoder, and Memory-Augmented Deep Autoencoder (MemAE). Our results show that the preprocessed datasets using both ADASYN and SMOTE significantly improved the performance of all models, achieving higher precision, recall, and F1-Score values. Notably, the best performance was obtained when using the preprocessed dataset (SMOTE) with the MemAE model, yielding an F1-Score of 1.00. The evaluation was also conducted by measuring the Area Under the Receiver Operating Characteristic Curve (AUROC), which showed that all models performed well with an AUROC of over 90%. Our proposed method provides a promising approach for detecting and classifying malicious behavior in host process data using machine learning algorithms, which can be used in various fields such as anomaly detection and medical diagnosis. [ABSTRACT FROM AUTHOR]

When it is necessary to detect various physiological signals of the human body, clothing embroidered with near-field effect patterns can be used as a long-term power supply medium to supply power to long-distance transmitters and receivers to form a wireless power supply system. The proposed system uses an optimized parallel circuit to achieve a power transfer efficiency of more than five times higher than that of the existing series circuit. The power transfer efficiency of simultaneously supplying energy to multiple sensors is increased higher than five times and even more when only one sensor is coupled. When powering eight sensors at the same time, the power transmission efficiency can reach 25.1%. Even when eight sensors powered by the coupled textile coils are reduced to one, the power transfer efficiency of the whole system can reach 13.21%. Additionally, the proposed system is also applicable when the number of sensors ranges from 2 to 12. [ABSTRACT FROM AUTHOR]

Wireless power and bidirectional wireless data transfer system using a conventional 2-coil inductive link is presented for Internet-of-Things (IoT) and mobile applications without any additional coil or antenna. The proposed system utilizes the dual-band frequency shift-keying and the load shift-keying for the downlink and uplink telemetries, respectively, while ∼140 mW power is delivered to the receiver in the 2-coil inductive link. The data rates for downlink and uplink telemetries are 800 kb/s and 14 kb/s with 3.12 × 10−5 and <10−6 bit error rate at 10 mm distance, respectively. [ABSTRACT FROM AUTHOR]

To enhance the performance of OLED Micro‐display, we developed the ultra‐high resolution RGB direct patterning of OLED Micro‐display. 3,000ppi FMM by UV Laser process was used and this FMM is manufactured by our unique Laser Patterning process. To improve the luminous efficiency of the OLED Micro‐display device, the RGB dual stack structure was implemented and RGB color filter was applied to improve the color purity. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NALFD), characterized by an abnormal accumulation of triglycerides in hepatocytes, is closely linked to insulin resistance, metabolic syndrome, and changes in lipogenesis in the liver. The accumulation of hepatic lipids can lead to a range of pathologies from mild steatosis to severe cirrhosis. Endurance exercise is known to ameliorate the adverse health effects of NAFLD. Therefore, we aimed to investigate the effect of voluntary wheel running (VWR) on the metabolic changes in the livers of high-fat diet (HFD)-induced NAFLD mice and used LC-MS/MS (Liquid chromatography–mass spectrometry) to determine whether the tested intervention affected the protein expression profiles of the mouse livers. Male C57BL/6 mice were randomly divided into three groups: control (CON), high-fat diet sedentary group (HFD), high-fat diet VWR group (HFX). HFX group performed voluntary wheel running into individually cages, given a high-fat diet for 12 weeks. Food consumption, body weight, and running distance were measured every week. Using 2D (2-dimensional)-gel electrophoresis, we detected and quantitatively analyzed the protein expression with >2.0-fold change in the livers of HFD-fed mice, HFD-fed exercise (HFX) mice, and chow-fed mice. Body weight was significantly increased in HFD compared to CON (P < 0.05). The 2D-gel electrophoresis analysis indicated that there was a difference between CON and HFD groups, showing 31 increased and 27 decreased spots in the total 302 paired spots in the HFD group compared to CON. The analysis showed 43 increased and 17 decreased spots in the total 258 spots in the HFX group compared to CON. Moreover, 12 weeks of VWR showed an increase of 35 and a decrease of 8 spots in a total of 264 paired spots between HFD and HFX. LC-MS/MS of HFD group revealed that proteins involved in ketogenesis, lipid metabolism, and the metabolism of drugs and xenobiotics were upregulated, whereas detoxifying proteins, mitochondrial precursors, transport proteins, proteasomes, and proteins involved in amino acid metabolism were downregulated. On the other hand, VWR counteracted the protein expression profile of HFD-fed mice by upregulating molecular chaperones, gluconeogenesis-, detoxification-, proteasome-, and energy metabolism-related proteins. This study provided a molecular understanding of the HFD- and exercise-induced protein marker expression and presented the beneficial effects of exercise during pathophysiological conditions. [ABSTRACT FROM AUTHOR]

Full-duplex (FD) enabled wireless power transfer (WPT) system via textile for miniaturized IMD is presented. By utilizing the battery-free near-field communication (NFC) method, the system realizes wireless power and data transmission without a bulky battery or energy harvester which can diminish the physical size of implantable medical device (IMD). Moreover, using textile as a medium of power transmission, the system overcomes the drawback and extends the limited effective range of the NFC method. In addition, as realizing simultaneous bidirectional data transmission over a single data channel, IMD has been further miniaturized. The proposed system including an external transmitter and the minimized IMD receiver supports 200 kbps and 50 kbps data rates for FSK downlink and LSK uplink telemetries at the same time with bit error rate (BER) of < 8 × 10 - 5 and < 4 × 10 - 5 , respectively. The measured power transfer efficiency (PTE) and DC-to-DC power delivered to load (PDL) are 5.77% and 64 mW at 0.5/60 cm of vertical/horizontal distance. [ABSTRACT FROM AUTHOR]

A low-cost 80×60 microbolometer CMOS (complementary metal-oxide-semiconductor) thermal imager is presented. The imager system integrated with a proposed 12-b biasing digital-to-analog converter (DAC) has 100 ms start-up time, which is 300× faster than commercial products, while ensuring comparable 100 mK noise-equivalent temperature difference. The low-noise biasing DAC adopts a current-mode divider-stacking structure and a bit-inversion technique, leading to mismatch-insensitive operation. The 12-b biasing DAC in a 0.18 μm CMOS imager IC has a low noise of 1.89 μVrms and INL (integral non-linearity)/DNL (differential non-linearity) of 0.14/0.09 LSB, respectively. [ABSTRACT FROM AUTHOR]

Obesity is a common metabolic disorder caused by a sedentary lifestyle, and a high-fat and a high-glucose diet in the form of fast foods. High-fat diet-induced obesity is a major cause of diabetes and cardiovascular diseases, whereas exercise and physical activity can ameliorate these disorders. Moreover, exercise and the gut microbiota are known to be interconnected, since exercise can increase the gut microbial diversity and contribute to the beneficial health effects. In this context, we analyzed the effect of diet and exercise on the gut microbiota of mice, by next-generation sequencing of the bacterial V4 region of 16S rRNA. Briefly, mice were divided into four groups: chow-diet (CD), high-fat diet (HFD), high-fat diet + exercise (HFX), and exercise-only (EX). The mice underwent treadmill exercise and diet intervention for 8 weeks, followed by the collection of their feces and DNA extraction for sequencing. The data were analyzed using the QIIME 2 bioinformatics platform and R software to assess their gut microbial composition, richness, and diversity. The Bacteroidetes to Firmicutes ratio was found to be decreased manifold in the HFD and HFX groups compared to the CD and EX groups. The gut microbial richness was comparatively lower in the HFD and HFX groups and higher in the CD and EX groups (ACE, Chao1, and observed OTUs). However, the Shannon alpha diversity index was higher in the HFD and HFX groups than in the CD and EX groups. The beta diversity based on Jaccard, Bray–Curtis, and weighted UniFrac distance metrics was significant among the groups, as measured by PERMANOVA. Paraprevotella, Desulfovibrio, and Lactococcus were the differentially abundant/present genera based on the intervention groups and in addition to these three bacteria, Butyricimonas and Desulfovibrio C21c20 were differentially abundant/present based on diet. Hence, diet significantly contributed to the majority of the changes in the gut microbiota. [ABSTRACT FROM AUTHOR]

Regular exercise provides several health benefits that can improve the cardiovascular and musculoskeletal systems, but clear evidence on the effect of exercise-induced hyperventilation in particulate matter (PM) exposure is still lacking. This study aimed to investigate the effects of exercise in PM exposure on reactive oxygen species (ROS) generation, inflammatory response, and mitochondrial integrity in human lung epithelial cells (A549), as well as in mouse lung tissue. In in vitro experiments, PM treatment was shown to significantly increased ROS production, and reduced cell viability and mitochondrial function in A549 cells. The mice were divided into four groups for an in vivo exercise experiment: control (CON), PM inhalation (PI), PM inhalation during exercise (PIE), and exercise (EX) groups. The PI and PIE groups were exposed to 100 μg/m3 of PM for 1 h per day for a week. The PIE and EX groups performed treadmill exercises every day for 1 h at 20 m/min for a week. The levels of pro-inflammatory markers (IL-6 and TNF-α) were significantly higher in the PI group than in the CON group (P < 0.001 and P < 0.01, respectively). The carbonyl protein level was decreased in EX vs. PI (P < 0.001). Mitochondrial fission (Drp1) content was significantly decreased in the EX vs. CON group (P < 0.01), but anti-mitochondrial fission (P-Drp1 Ser637) was increased in the EX vs. PI group (P < 0.05). Mitochondrial autophagy (mitophagy), which is an assessment of mitochondrial integrity, was markedly increased in PI vs. CON (P < 0.001), but the level was reversed in PIE (P < 0.05). Lung fibrosis was increased in PI vs. CON group (P < 0.001), however, the cells were rescued in the PIE (P < 0.001). The number of apoptotic cells was remarkably increased in the PI vs. CON group (P < 0.001), whereas the level was decreased in the PIE (P < 0.001). Taken together, these results showed that short-term exposure to PM triggers oxidative stress, pro-inflammatory responses, and apoptosis in the lungs, but the PM-induced adverse effects on the lung tissue are not exacerbated by exercise-induced PM hyperventilation but rather has a protective effect. [ABSTRACT FROM AUTHOR]

Bio-aviation fuel to satisfy ASTM (American Society for Testing and Materials) specification was prepared through the stable operation of bio-aviation fuel manufacturing facility scale-expanded up to the production of bio-aviation fuel for turbine engine test. First, powder-typed 1.0 wt% Pt/Al2O3 and 0.5 wt% Pt/zeolite catalysts, respectively applicable to the hydrotreating and upgrading processes, were prepared and then their performance was evaluated in laboratory scale reactor. Thereafter, pellet-shaped 1.0 wt% Pt/Al2O3 and 0.5 wt% Pt/zeolite catalysts were prepared and applied to a bench-scale hydrotreating process and an upgrading process reactor, applied in the catalytic processes to prepare bio-aviation fuel. At this time, reaction characteristics under various operating conditions were investigated along with their catalytic performance evaluation. Stable long-term operation based on optimal reaction conditions, obtained in bench-scale reactor was performed using the hydrotreating process and the upgrading process reactors in a pilot-scale bio-aviation fuel manufacturing facility to continuously operate during a long time under optimal reaction conditions controlled, and then synthetic bio-crude oil including bio-aviation fuel composition was prepared. Through the separation and purification process that can selectively obtain bio-aviation fuel components, bio-aviation fuel conforming to ASTM specification standards was produced from the synthetic bio-crude oil obtained through combined hydrotreating-upgrading process. [ABSTRACT FROM AUTHOR]

A robust multioutput self-regulated rectifier without any switching circuitry is proposed in this letter for wirelessly powered biomedical devices, especially for neural stimulators. The proposed system utilizes the series and parallel resonant configuration for low- and high-side outputs, respectively, by using only one resonant capacitor. The proposed system provides dual high voltages of ±14 V for neuro stimulator and low voltage of 2.1 V for operating systems such as read-out and digital circuits. [ABSTRACT FROM AUTHOR]

In our previous study, we verified that a two-step process was superior to the one-pot process for the manufacture of THTCPD, assuming the pilot-scale production aspect of a comparative economic analysis by using an engineering estimation method to predict the unit manufacturing cost. Among the processes of the two-step process, our study was intended to focus on the isomerization to produce the final THTCPD products with outstanding physical properties including a specific gravity, a heat of combustion, a viscosity and a freezing point. Although HY(30) was used as an isomerization catalyst in the previous study, the catalytic activity of HY(30) did not surpass that of AlCl3 in terms of isomerization conversion, possibly due to lower exo-THTCPD selectivity by Brönsted acid sites of HY(30) than that by Lewis acid sites of AlCl3. However, AlCl3 has some drawbacks of the impossibility for the catalyst regeneration during the manufacturing process due to the difficulty of the catalyst separation and recovery after isomerization, which causes environmental problems and biological toxicity issues due to its corrosivity. Therefore, our study concentrated on catalyst regeneration assuming the real production process in a pilot scale using AlCl3 in comparison with HY(30). Then, we investigated whether the isomerization catalyst AlCl3 or HY(30) was more commercially favorable through a comparative unit production cost prediction applying an engineering estimation in this study. In conclusion, the unit production cost for AlCl3 was lower than that for HY(30) with the fresh catalyst. Reversely, unit production costs for HY(30) with increase in catalysts regeneration number (N) were lower than those for AlCl3 due to the drastic decrease in the unit material cost of HY(30) unlikely with that of AlCl3 due to its non-reusability. [ABSTRACT FROM AUTHOR]

To provide power to the latest mobile applications that use functions with heavy loads, in this letter, we present a capacitorless low-dropout regulator (LDO) that supplies a large load current up to 600 mA. The proposed buffer and the feedforward paths are used to provide a stable operation and fast response along with a large load current. Owing to these schemes, the proposed LDO has a high unity gain frequency of 2.85 MHz at 100 mA with a total compensation capacitance of 5.1 pF. In addition, the LDO operates under a wide input voltage range of 1.5–5.0 V owing to the low-VDD structure. Also, a power supply rejection ratio was –52 dB at 100 kHz. The chip was implemented with a small size of 0.082 mm2 using the I/O devices of a 0.18 μm CMOS process with a minimum length of 0.5 μm. [ABSTRACT FROM AUTHOR]

Corporate Social Responsibility (CSR) has already become an important issue in Japan & Korea as well as in China. However, a relatively clear difference of CSR practice of China has existed due to it being government-led CSR practice. The Chinese government actively promotes its CSR standards, the CASS CSR 3.0 while emphasizing Chinese characteristics. This study traces the difference of CSR practice for Chinese firms by looking into twenty-four automakers' CSR websites and reports in Japan, Korea and China. Firstly, this study analyzes CSR reports and website accessibility from a local language barrier perspective, and does Paired t-Test for comparing two national populations means of accessibility between two groups; Japanese-Korean automakers vs. Chinese automakers by using survey results. Secondly, the coverage rates of each automaker's CSR report for GRI G4 are examined, and Two-Sample t-Tests are made to compare the two nationalities means of coverage rate between Japanese-Korean automakers and Chinese ones. As a result, the CSR practices of Chinese automakers differ greatly from CSR practices of Japanese- Korean ones. But it needs to be considered that if the major stakeholders of Chinese firms are local people or partners, the core of CSR activities would be oriented for local stakeholders. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) has recently emerged as a prominent technology to liberate various applications with small devices from limited mobility and design constraints. Among various techniques, magnetic field focusing (MFF) with multiple transmit (Tx) coils have been known as a powerful solution to enhance the efficiency of power transfer to multiple receivers (Rxs) in midrange WPT. However, in such MFF techniques, even unintended Rx may suffer from unwanted power due to leakage, which may disrupt the operations of the devices. Motivated by this issue, in this article, we consider selective magnetic resonance coupling (MRC)-based WPT, which enables WPT systems to better shape power distribution only focusing on the intended Rxs while leakages to the unintended Rx are suppressed. To this end, we first formulate the selectivity requirement of WPT as an optimization problem. Then, we propose a method to obtain the optimal Tx voltage vector for simultaneous MFF and null-steering optimization. Simulation and experimental results validate the theoretical analysis and the proposed method in practical scenarios. [ABSTRACT FROM AUTHOR]

This paper proposes a multiphase resonance-based rectifier (MPRR), capable of delivering power to multiple loads with large difference in their output voltages. This behavior is particularly useful for wireless sensors and actuators, in which the micromachined transducer/actuator needs a high voltage to operate but the interface circuitry requires only a fraction of that voltage. This is achieved by shorting the receiver (Rx) L3C3-tank to increase its loaded quality factor, QRx, over several cycles to accumulate wirelessly transferred energy in the inductor during this period, and then first break the loop in-phase, by connecting the L3C3-tank to the in-phase load (RL,I), to transfer energy at low voltage in a half cycle (in-phase charging), and then transfer energy to the quadrature load (RL,Q) through a diode in a quarter cycle at high voltage (quadrature charging). By optimizing the number of cycles for in-phase charging, NI, and quadrature charging, NQ, through an iterative design procedure, the MPRR can achieve the highest power delivered to the load under a given set of design constraints. Governing equations in the MPRR operation are derived to identify the key specifications for the design procedure. Using an exemplar set of specifications, the optimized MPRR was able to generate 21.5 and 1.84 V across 100 kΩ and 200 Ω loads, respectively, from a class-D power amplifier operating at 15 V, 6.78 MHz sinusoid input in the industrial-scientific-medical band (ISM-band) at a Tx/Rx coil separation of 1.3 cm with NI = 3 cycles, NQ = 6 cycles, and IQRatio = 5. [ABSTRACT FROM AUTHOR]

To eliminate tethering effects on the small animals’ behavior during electrophysiology experiments, such as neural interfacing, a robust and wideband wireless data link is needed for communicating with the implanted sensing elements without blind spots. We present a software-defined radio (SDR) based scalable data acquisition system, which can be programmed to provide coverage over standard-sized or customized experimental arenas. The incoming RF signal with the highest power among SDRs is selected in real-time to prevent data loss in the presence of spatial and angular misalignments between the transmitter (Tx) and receiver (Rx) antennas. A 32-channel wireless neural recording system-on-a-chip (SoC), known as WINeRS-8, is embedded in a headstage and transmits digitalized raw neural signals, which are sampled at 25 kHz/ch, at 9 Mbps via on-off keying (OOK) of a 434 MHz RF carrier. Measurement results show that the dual-SDR Rx system reduces the packet loss down to 0.12%, on average, by eliminating the blind spots caused by the moving Tx directionality. The system operation is verified in vivo on a freely behaving rat and compared with a commercial hardwired system. [ABSTRACT FROM AUTHOR]

This paper presents a mm-sized, free-floating, wirelessly powered, implantable optical stimulation (FF-WIOS) device for untethered optogenetic neuromodulation. A resonator-based three-coil inductive link creates a homogeneous magnetic field that continuously delivers sufficient power (>2.7 mW) at an optimal carrier frequency of 60 MHz to the FF-WIOS in the near field without surpassing the specific absorption rate limit, regardless of the position of the FF-WIOS in a large brain area. Forward data telemetry carries stimulation parameters by on-off-keying the power carrier at a data rate of 50 kb/s to selectively activate a 4 × 4 μLED array. Load-shift-keying back telemetry controls the wireless power transmission by reporting the FF-WIOS received power level in a closed-loop power control mechanism. LEDs typically require high instantaneous power to emit sufficient light for optical stimulation. Thus, a switched-capacitor-based stimulation architecture is used as an energy storage buffer with one off-chip capacitor to receive charge directly from the inductive link and deliver it to the selected μLED at the onset of stimulation. The FF-WIOS system-on-a-chip prototype, fabricated in a 0.35-μm standard CMOS process, charges a 10-μF capacitor up to 5 V with 37% efficiency and passes instantaneous current spikes up to 10 mA in the selected μLED, creating a bright exponentially decaying flash with minimal wasted power. An in vivo experiment was conducted to verify the efficacy of the FF-WIOS by observing light-evoked local field potentials and immunostained tissue response from the primary visual cortex (V1) of two anesthetized rats. [ABSTRACT FROM AUTHOR]

This paper presents the development and control methodology of a military rescue robot for a casualty extraction task. The new rescue robot (HURCULES) equipped with electric actuators for the casualty extraction task on the battle field is introduced. In this paper, mechanical designs of the HURCULES are described in detail. One of the noticeable features in the mechanical design is to use the worm gear in the joint to maintain the safety of the casualty even with power‐off and to reduce the energy through a selected operating mode. Moreover, unlike the upper body of a conventional humanoid robot, the chest plate is installed and used to properly distribute the casualty's weight to the dual‐arm manipulator and the chest plate when carrying the wounded person. The HURCULES is valuable because the rescue robots for use on the battle field are very rare. And, the HURCULES is the first rescue robot for use on the battle field in South Korea. Primarily, a semiautonomous control strategy is applied to the HURCULES. The maneuvering stability of the HURCULES is needed when approaching and escaping a casualty while maneuvering on uneven terrain, and it maintains autonomously by the HURCULES. A variety of maneuvering experiments on various terrains were conducted, and satisfactory results for the casualty extraction task were obtained. In particular, the field experiments in this paper were performed at an accredited test site. Besides, additional experiments were conducted to enhance the field applicability. [ABSTRACT FROM AUTHOR]

This paper presents an area and power efficient interpolation scheme using variable current control (VCC) for 10-bit data drivers in mobile active-matrix LCDs. The VCC interpolation can be embedded in buffer amplifiers as sub-digital-to-analog converters (DACs), reducing the DAC area without requiring additional power and conversion time. Moreover, interpolation errors due to transistor nonlinearity can be compensated through delicate current ratio control, optimizing both accuracy and area efficiency of the high-resolution data driver. The prototype 10-bit data driver with a 6-bit resistor DAC and a 4-bit interpolation sub-DAC occupies the chip area of 460 ${\mu }{\text{m}}\,\,{\times }$ 14 ${\mu }{\text{m}}$ per channel, which is 10.7% smaller than the conventional 8-bit data driver. The data driver consumes static current of 1 ${\mu }\text{A}$ /channel without dissipating additional power for interpolation. The measured integral nonlinearity and differential nonlinearity are 0.4 LSB and 0.7 LSB, respectively. The proposed scheme has competitive performance in terms of driving accuracy, chip size shrinkage, and static power consumption for high-resolution data drivers. [ABSTRACT FROM AUTHOR]

An inductively-powered wireless integrated neural recording and stimulation (WINeRS-8) system-on-a-chip (SoC) that is compatible with the EnerCage-HC2 for wireless/battery-less operation has been presented for neuroscience experiments on freely behaving animals. WINeRS-8 includes a 32-ch recording analog front end, a 4-ch current-controlled stimulator, and a 434 MHz on–off keying data link to an external software- defined radio wideband receiver (Rx). The headstage also has a bluetooth low energy link for controlling the SoC. WINeRS-8/EnerCage-HC2 systems form a bidirectional wireless and battery-less neural interface within a standard homecage, which can support longitudinal experiments in an enriched environment. Both systems were verified in vivo on rat animal model, and the recorded signals were compared with hardwired and battery-powered recording results. Realtime stimulation and recording verified the system's potential for bidirectional neural interfacing within the homecage, while continuously delivering 35 mW to the hybrid WINeRS-8 headstage over an unlimited period. [ABSTRACT FROM AUTHOR]

A two-stage stochastic programming algorithm based on particle swarm optimization is proposed for an optimal and robust design in the aircraft sequencing and scheduling problem. The first and second stage decision problems are defined as aircraft sequencing and scheduling, respectively, and the uncertainties that arise from the aircraft flight time between two successive fixes are considered. Particle swarm optimization is utilized for a randomized search to make the first stage decision under incomplete information about uncertain parameters. In addition, the random key representation is adopted to apply particle swarm optimization to a discrete aircraft sequencing problem. Then, the second stage decision is made using mixed integer linear programming after the realization of the uncertain parameters. The performance of the proposed algorithm is verified by numerical simulations. [ABSTRACT FROM AUTHOR]

In modern implantable medical devices (IMDs), wireless data transmission between inside and outside of the body is essential to control IMD parameters and report the acquired data to the external part of the system. Unlike conventional far-field data communication, which is more suitable for free space, near-field data transfer techniques have been widely adopted for transcutaneous data links in IMDs. These data links should be designed for robustness against misalignments and interference, while maintaining high power efficiency, sufficient bandwidth, and communication range in either uplink (IMD to outside) and/or downlink (wearable external part to IMD). In this article, we review fundamental principles and practical considerations for designing short-range transcutaneous data telemetry, along with novel techniques presented in the literature, which are categorized in uplink/downlink, passive/active, single/multi-carrier, and carrier-less pulse-based data telemetry methods. [ABSTRACT FROM AUTHOR]

This article presents a design and control framework for a prototype of lower extremity exoskeleton to enhance the human strength during locomotion. The hybrid control strategy is practically applied according to the two gait phases, that is, stance and swing. The weight shift method based on human's weight shift information was proposed and implemented to acquire the detection of gait phase. In the stance phase, a stiff virtual wall method is applied to support the entire weight of the exoskeleton while carrying a heavy payload. Direct feedback and feed-forward torque control are used to reduce mechanical impedance in the swing phase. In experiments, to verify the performance of the proposed control strategy, a human subject wearing the prototype of power-augmenting lower extremity exoskeleton was able to walk with a 50-kg (110-lb) payload at a maximum speed of 1.67 m/s (6 km/h). Satisfactory results were obtained with regard to walking experiments with the heavy payload. [ABSTRACT FROM AUTHOR]

This paper proposes a new sequencing and scheduling algorithm for the point merge system based on mixed integer linear programming considering the uncertain flight time of aircraft. In the first stage of the proposed algorithm, for a static environment, deterministic robust solutions are determined. To consider the uncertainty, an extra buffer is introduced in the sequencing and scheduling algorithm, and the buffer size is analytically derived by generating a deterministic robust counterpart problem. In the second stage, to compensate for unforeseen situations under a dynamic environment, the static solution determined in the first stage is adjusted by using the proposed heuristic algorithm, with a sliding time window to reduce the computational load. The performances of the proposed algorithm are verified via numerical simulations based on historical data analysis. [ABSTRACT FROM AUTHOR]

This paper proposes practical hardware design strategies and control methods for a rescue robot to save patients in disastrous environments. None of the existing humanoid robots have not shown the capability to efficiently execute rescue tasks for transferring a human to a safe place in a highly unstructured world. To resolve this problem a new form of powerful dual arm mechanism and hybrid tracked-legged mobile platform is developed and the motion is synthesized with dynamics based optimization and a modified hierarchical control scheme. These new design and control policies enable us to simultaneously enhance the manipulation performance and driving stability which have been verified through both in extensive numerical simulations and physical experiments where the rescue robot and whole-body control are indeed required. [ABSTRACT FROM AUTHOR]

An adaptive averaging low noise analog front-end (AFE) is presented for central and peripheral nerve recording applications. The proposed topology allows users to trade off, on the fly, between input referred noise and the number of channels via averaging. The new low noise amplifier (LNA) utilizes a complementary doubled input transconductance ( ${g}_{m}$ ) topology to effectively increase the noise efficiency factor without chopping or use of a costly BiCMOS process. It addresses a disadvantage of the doubled- $ {g}_{m}$ technique by a high input impedance DC-coupled LNA and saves on-chip space for higher density by eliminating AC-coupling capacitors. The proposed technique is particularly suitable for ultra-low noise multichannel recording from the peripheral nervous system with a channel selection analog multiplexer, where the input signal is in tens of ${\mu }\text{V}$. A 32-ch proof-of-concept-prototype AFE was fabricated in a 5M2P 130-nm standard CMOS process, occupying $2.4\,\,{ \times } \,\, 2.5$ mm $^{2}$ together with its control block. The prototype LNA consumes 11 ${\mu }\text{W}$ from a 1-V supply, providing 3.0- ${\mu }\text{V}_{\text {rms}}$ input referred noise with 61- $\text{M}{\Omega }$ input impedance, which are desirable for high SNR, to be further improved by the adaptive averaging technique. [ABSTRACT FROM AUTHOR]

Background: The preemptive multimodal pain protocols used in total knee arthroplasty (TKA) often cause emesis postoperatively. We investigated whether palonosetron prophylaxis reduces postoperative nausea and vomiting (PONV) in high-risk patients after TKA. Methods: We randomized 120 female patients undergoing TKA to receive either palonosetron (0.075 mg, intravenous) or no antiemetic prophylaxis (0.9% saline, control group). All patients were given spinal anesthesia, a continuous femoral nerve block, and fentanyl-based intravenous patient controlled analgesia. Patients undergoing staged bilateral TKA were assigned to one group for the first knee and the other group for the second knee. The overall incidence of PONV, the incidences of both nausea and vomiting, severity of nausea, complete response, requirement for rescue antiemetics, pain level, opioid consumption, and satisfaction scores were evaluated during three periods: 0–2, 2–24, and 24–48 h postoperatively. We also compared PONV and pain between the first and second TKA. Results: The incidence of PONV during the first 48 h was lower in the palonosetron group compared with the controls (22 vs. 41%, p = 0.028), especially 2–24 h after surgery, as was the nausea and vomiting respectively. The severity of nausea was lower in the palonosetron group (p = 0.010). The complete response rate (93 vs. 73%, p = 0.016) and satisfaction score (84 ± 12 vs. 79 ± 15, p = 0.032) were higher in the palonosetron group during 2–24 h after surgery. Patients who underwent a second operation complained of more severe pain, and consumed more opioids than those of the first operation. There was no difference in the incidence of PONV between the first and second operations. Conclusions: Palonosetron prophylaxis reduced the incidence and severity of PONV in high-risk patients managed with multimodal pain protocol for 48 h, notably 2–24 h after TKA. [ABSTRACT FROM AUTHOR]

This paper presents the maneuvering stabilization method for the rescue robot. In general, the stability index such as center of mass (CoM), zero moment point (ZMP), moment height stability (MHS), and force angle (FA) measure during maneuvering can be used for the mobile manipulator. Among these stability indices, the appropriate stability index can be determined according to the target application. In this paper, the new rescue robot is introduced to accomplish various missions including the rescue and maneuver with a wounded person. The CoM as the stability index is determined due to relatively low closed-loop bandwidth of the tracked lower body for the rescue robot. Therefore, the maneuvering stability can be practically obtained by using the CoM tracking control method. Furthermore, the position-based motion control method using the closed-loop inverse kinematics (CLIK) algorithm is used for the HURCULES. To verify the effectiveness of the CoM tracking controller using the CLIK method, the experiments were conducted on a longitudinal slope and uneven terrain. Satisfactory performance of the maneuvering stabilization was obtained from the experimental results. [ABSTRACT FROM AUTHOR]

C-reactive protein and albumin are associated with poor outcomes in critically ill patients. This study aimed to investigate the significance of the C-reactive protein/albumin (CRP/ALB) ratio as a novel prognostic factor for 30-day or 1-year mortality after admission to the postoperative intensive care unit (ICU). This retrospective study was conducted by examining the medical records of postoperative patients aged 19 years or older admitted to the ICU at a tertiary care hospital from January 2007 to July 2016. This study included data on 11,832 postoperative patients in the analysis. The cut-off value of the CRP/ALB ratio was set at 1.75 and 1.58 for 30-day and 1-year mortality after ICU admission, respectively. In postoperative patients with a high CRP/ALB ratio (>1.75 or >1.58), the probability of death within 30 days or 1 year after ICU admission were 30% or 43% higher than that in the group with the least CRP/ALB ratio, respectively (≤1.75 or ≤1.58)(p < 0.05). This study found the CRP/ALB ratio measured immediately after ICU admission to be an independent risk factor for 30-day and 1-year mortality in postoperative patients admitted to the ICU. [ABSTRACT FROM AUTHOR]

This paper presents the design procedure for a new multicycle resonance-based voltage boosting rectifier (MCRR) capable of delivering a desired amount of power to the load (PDL) at a designated high voltage through a loosely coupled inductive link. This is achieved by shorting the receiver (Rx) LC\--\tank for several cycles to harvest and accumulate the wireless energy in the RX inductor before boosting the voltage by breaking the loop and transferring the energy to the load in a quarter cycle. By optimizing the geometries of the transmitter (Tx) and Rx coils and the number of cycles, $N$, for energy harvesting, through an iterative design procedure, the MCRR can achieve the highest PDL under a given set of design constraints. Governing equations in the MCRR operation are derived to identify key specifications and the design guidelines. Using an exemplary set of specs, the optimized MCRR was able to generate 20.9 $V_{{\rm{dc}}} across a 100 kΩ load from \text1.8\,Vp, 6.78-MHz sinusoid input in the industrial-scientific-medical-band at a Tx/Rx coil separation of 1.3 cm, power transfer efficiency of 2.2%, and N=9 cycles. At the same coil distance and loading, coils optimized for a conventional half-wave rectifier were able to reach only 13.6 $V_{{\rm{dc}}}$ from the same source. [ABSTRACT FROM PUBLISHER]

In this study, a proposed three-dimensional (3-D) grid strut-and-tie model approach is verified using the experimental capacity from 78 reinforced concrete pile caps, 19 slab-column joints, and 60 torsional beams obtained by others. The analysis results were compared with those obtained using the BS 8110, EC2, CRSI, fib, AASHTO-LRFD, and ACI 318 design provisions. In addition, the design of a pier cap subjected to multiple load combinations with longitudinal and lateral loads was conducted to illustrate the proposed approach. The design results from the pier cap example were also compared with those obtained using ACI 318-14. The analysis results agreed well with experimental results. [ABSTRACT FROM AUTHOR]

The strut-and-tie model approach has now been incorporated in current U.S. design codes and guidelines for the design of disturbed regions in structural concrete elements. However, more work is needed to extend the approach to design of three-dimensional (3-D) structural concrete. It is also important to consider its verification with experimental evidence. The application to 3-D design situations of this approach brings more uncertainties with its proper application and limitations. To reduce uncertainty and assist designers in the application of the strut-and-tie model to 3-D situations, the authors present in this paper a 3-D grid strut-and-tie model approach consisting of three key steps: 1) grid elements to construct a 3-D strut-and-tie model; 2) triaxial failure model of concrete to determine effective strengths of concrete struts and nodal zones; and 3) iterative technique to evaluate the axial stiffness of struts and ties. In this paper, the authors also incorporate in the strut-and-tie model a new concept of maximum cross-sectional areas of struts and ties to examine the strut-and-tie model's geometrical compatibility. The approach is illustrated with the redesign of a deep pile cap with tension piles available in the literature. In a subsequent paper, the authors will evaluate the approach with test results of 157 specimens tested to failure. The tests include 78 reinforced concrete pile caps, 19 slab-column joints, and 60 beams subjected to torsion. [ABSTRACT FROM AUTHOR]

A new optimization problem to resolve conflicts by allowing aircraft to change both their heading angle and speed is considered. The performance index in the optimization problem is formulated to reduce the variation of the aircraft arrival time that is caused by conflict resolution maneuvers. To achieve both conflict resolution and flow management, metering constraints are introduced together with separation constraints. Even though the performance index and constraints are nonlinear, the optimal solution can be easily obtained by utilizing particle swarm optimization. Numerical simulations are performed to evaluate the performance of the proposed algorithm, and the numerical experimental results showed a significant reduction in the variation of the aircraft arrival time as well as the magnitude of heading angle and speed changes. [ABSTRACT FROM PUBLISHER]

The activities of HY, Hbeta, HZSM-5 and mesoporous Al-MCM-41 catalysts were evaluated during the dimerization of bicyclo[2.2.1]hepta-2,5-diene (norbornadiene, NBD). This study focuses on the effects of the pore structure and acidity of the catalysts on the NBD dimerization reaction. When conducting the NBD dimerization reaction over the HY, Hbeta, HZSM-5 and Al-MCM-41 catalysts, it was confirmed that NBD dimer (NBDD) synthesis could be facilitated at a temperature of 250 °C, whereas NBD scarcely reacts through a thermal reaction without a catalyst. Although the NBD conversion rates of the four catalysts are nearly identical after a 12-h reaction, the HY zeolites showed much higher selectivity to NBDD than those with the Hbeta, HZSM-5 and Al-MCM-41 catalysts. The HY catalyst showed the highest yield, reaching 41.5 wt% after a 12-h reaction. The higher selectivity of the HY catalyst during the dimerization of NBD could be explained in terms of its appropriate pore structure and by the higher concentration of Brønsted acid sites. The present study reveals that the HY zeolite is a potential heterogeneous catalyst for NBDD synthesis through the dimerization of NBD at a high yield. [ABSTRACT FROM AUTHOR]

We herein report substitutional doping effects on the electronic and thermal transport properties of higher manganese silicides (HMS) MnSi. Polycrystalline bulks of MnASi and MnSiB (A = V, Cr, Mo/B = Al, Ge) were fabricated by a solid-state reaction combined with the spark plasma sintering technique, and their thermoelectric properties were evaluated. We found that thermoelectric performance of MnSi was significantly enhanced due to the simultaneous improvement in electronic transport and phonon scattering via partial substitution of foreign atoms at Mn- and/or Si-sites. Through the small amount of Cr doping at the Mn-site and Al and Ge doping at the Si-site, the power factor was improved due to enhancement in density of the state's effective mass. Thermal transport properties could be also manipulated due to the point defect phonon scattering effect, and reduced lattice thermal conductivity was obtained with Ge-doped HMS. As a consequence, the maximum dimensionless figure␣of merit ZT of 0.64 at 773 K (increased 50% compared to undoped MnSi) was obtained in Ge-doped MnSi. [ABSTRACT FROM AUTHOR]

A new framework for conflict resolution in air traffic control is studied using air traffic complexity, which ensures conflict avoidance among aircraft and smooth transition of aircraft into adjacent airspace. The air traffic complexity is modeled as deviations in heading angle or speed of the aircraft inside a sector to resolve any conflict induced by the entering aircraft. For conflict management in multisector planning, a two-level hierarchical architecture is proposed. In the higher level, the maneuver constraints of the aircraft are constructed to minimize complexity for the neighboring sectors. In the lower level, the conflict avoidance problem is formulated as a mixed integer linear programming considering the maneuver constraints, which are defined in the higher level. With the two-level hierarchical architecture, the aircraft can find the optimal solution to resolve conflicts among the aircraft and reduce the air traffic complexity of the neighboring sectors. The performance of the proposed conflict management is demonstrated using numerical simulations. [ABSTRACT FROM PUBLISHER]

This paper presents a new method, called multicycle Q-modulation, which can be used in wireless power transmission (WPT) to modulate the quality factor (Q) of the receiver (Rx) coil and dynamically optimize the load impedance to maximize the power transfer efficiency (PTE) in two-coil links. A key advantage of the proposed method is that it can be easily implemented using off-the-shelf components without requiring fast switching at or above the carrier frequency, which is more suitable for integrated circuit design. Moreover, the proposed technique does not need any sophisticated synchronization between the power carrier and Q-modulation switching pulses. The multicycle Q-modulation is analyzed theoretically by a lumped circuit model, and verified in simulation and measurement using an off-the-shelf prototype. Automatic resonance tuning in the Rx, combined with multicycle Q-modulation helped maximizing PTE of the inductive link dynamically in the presence of environmental and loading variations, which can otherwise significantly degrade the PTE in multicoil settings. In the prototype conventional two-coil link, the proposed method increased the power amplifier plus inductive-link efficiency from 4.8% to 16.5% at ( RL = 1\, kW, d23 = 3\,cm), and from 23% to 28.2% at (RL = 100\,{\Omega}, d23 = 3\,cm) after 11% change in the resonance capacitance, while delivering 168.1 mW to the load (PDL). [ABSTRACT FROM PUBLISHER]