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We used light to irradiate skin-derived stem cells and tried to find any cellular protein alterations 24 h after illumination. A 266-nm laser with four intensities was used, and of the nine cell markers that were surveyed in our trials, only CD90 was downregulated at an intensity of 20 μJ for 10 s. Repeated illuminations from the 266-nm laser at seven intensities revealed that CD90 expression was downregulated 14.6–28.8%, depending on light intensity. The maximal effect was noted at an intensity of 30 μJ for 2 s. This innovative finding reveals that a 266-nm laser can regulate protein expression in skin-derivative stem cells.

We present a study on the quantification of energy dissipation of Micro-Electro-Mechanical System (MEMS) resonators. Toroidal Ring Gyroscope (TRG) was used as a platform to conduct the study. The main energy dissipation mechanisms in TRG include viscous air damping, Thermo-Elastic Damping (TED), anchor loss, and surface loss. During our experimental study, these energy dissipation mechanisms were minimized and controlled by venting the encapsulation and actively pumping down to high vacuum, cooling the temperature down to around 123 K, adjusting modal balance by electrostatic tuning, and pre-baking the device at high temperature (425 °C), respectively. At room temperature, the quality factor related to viscous air damping was measured to be 625,000, TED to be 170,000, and anchor loss to be 1,350,000. Finite Element Analysis (FEA) was conducted to support these findings. Relation between the anchor loss and electrostatic tuning was also explored. The effects of moisture-related surface loss have also been demonstrated by monitoring characteristics over a 2-year period of time. High temperature bake-out was proven to be effective in removing the moisture and reducing the surface loss. This paper combines topics that are scattered in literature on identification of energy dissipation mechanisms in kilohertz-range silicon MEMS resonators and presents the topic as a single methodology illustrating how the contribution of each energy dissipation mechanism can be quantified independently. To the best of our knowledge, this study is the first to experimentally quantify all major energy dissipation mechanisms in a kilohertz-range silicon MEMS resonator. [2020-0294]

Domain-switching kinetics of 5 mol% Y-doped HfO2 metal-insulator-metal (MIM) capacitor was characterized. The changes in polarization indicate the polarization reversal in HfO2. In this research, we show the polarization reversal of an 20-nm-thick Y-doped HfO2 deposited by atomic layer deposition (ALD) by switching the applied voltage (2.6 to 4.6V) and the pulse duration (1μs to 500μs). We use the measurements of Kolmogorov-Avrami-Ishibashi (KAI) model to extract the minimum switching time of the domains. Introduction Ferroelectric HfO2 layer has attracted attraction in CMOS and memory applications owing to its scaling ability and process compatibility. It has been demonstrated that doping of foreign elements, including Zr, Si, Al, Y, atoms under post-deposition annealing (PDA) or post-metallization annealing (PMA) induces the ferroelectricity in HfO2 [1]. The switching dynamics of ferroelectric Al- and Zr-doped HfO2 metal-insulator-metal (MIM) capacitors has been well-modeled by nucleation limited switching (NLS) model, where multigrain polarization takes place assuming a distribution in the switching time [2, 3]. In this study, we apply the KAI model to fit the switching dynamics of Y-doped HfO2 MIM capacitor using the following equation, , △P=Ps*(1-exp{-(t/τ)β }) where △P, P s, τ and β are the partial, saturation polarization, switching time constant and a fitting parameter, respectively [4]. Experiments An MIM capacitor with a 20-nm-thick 5 mol% Y-doped HfO2 film was fabricated by atomic layer deposition (ALD). The top and bottom electrode were both W deposited by sputtering. PMA was then carried out at 500 oC for 1 minute. Typical polarization-voltage (P-V) hysteresis is shown in fig. 1, where a remanent polarization (P r) of 12 mC/cm2 was obtained. A voltage waveform shown in fig. 2 was applied to the electrode to measure the polarization reversal of the devices after certain polling process. Polarization reversal was extracted by applying pulses with various height ranging from 2.6 to 4.6 V and width from 1 ms to 500 ms followed by half P-V measurement. Results and discussions Fig 3 shows measured partial polarization with different pulse width and voltage. As the pulse width increases, △P increases, indicating that a certain time is required to fully switch the domains. Data fit using the KAI model has well reproduced the measured data, indicating the presence of multigrain switching. However, a β of 0.6 to 0.8, which is smaller than those of Zr-doped HfO2 (typically b=2.1), needs to be used to fit the data. This may imply the difference in the domain size among dopants incorporated in the HfO2 layer. Conclusion Switching dynamics of ferroelectric Y-doped HfO2 MIM capacitors has been measured. The device has shown to follow the multidomain switching based on KAI model as is explained for Zr-doped HfO2 ones, except for the difference in the fitting parameter. References [1] J. Müller, et al., J. Appl. Phys., 110, 114113 (2011). [2] S. Zhukov, et al., Phys. Rev. B., 82, 014109 (2010). [3] C. Alessandri, et al., IEEE Electron Dev. Lett., 39, 1780 (2018). [4] N. Gong, et al., J. Appl. Phys., 112, 262903 (2018). Figure 1

In this innovative experiment, MDA-MB-231 cells were irradiated with a 266-nm laser for 5s, and then injected into NOD/SCID mice. The survival rate of the experimental mice was significantly reduced compared to that of the control mice (p=0.029), which also indicated the vitality of the experimental cells in vivo. The enhancement effect of a 266-nm laser on cells in xenotransplantation after 5 s of exposure was studied for the first time in this study. The findings of this study provide potential for future live cell therapies.

In this paper, we propose a hybrid altimeter for foot-mounted Inertial Navigation Systems (INS) aided by a barometer and a downward-facing ultrasonic sensor. The goal of developing the hybrid altimeter was to minimize the usage of barometric altimeter in height estimation as measurements of barometers are affected by changes in ambient temperature and air pressure. In this paper, we show that a shoe-mounted downward-facing ultrasonic sensor alone could be used as an altimeter on a variety of terrains, from flat surfaces to uneven stairs, by simultaneously estimating shoe height and floor elevation. We will refer to this type of altimeter as the ultrasonic altimeter. To account for other common indoor terrains, such as ramps and elevators, the developed hybrid altimeter uses a Multi-Model Kalman Filter to fuse measurements of a barometer and the ultrasonic altimeter. In the fusion process, the hybrid altimeter adaptively selects weights for the barometric and ultrasonic measurements based on the terrains under operation. We utilized a foot-mounted Inertial Measurement Unit (IMU) to realize the detection of elevators and ramps. We conducted three series of experiments to test the performance of the proposed hybrid altimeter. The first experiment showed that the proposed altimeter is less sensitive to temperature and air pressure changes in the surrounding environment than a barometer. The second series of experiments investigated the performance of the hybrid altimeter in the case of walking slowly on a flat plane, and the corresponding experimental results indicated that the Zero velocity UPdaTe (ZUPT)-based INS aided by the hybrid altimeter improved the Root Mean Square Error (RMSE) along the vertical direction by 96%, as compared to the standalone ZUPT-based INS, and by 97%, when compared to the ZUPT-based INS aided by the barometer. In the third series of experiments, we studied the navigation accuracy of the hybrid altimeter for common indoor terrains, such as flat surfaces, stairs, ramps, and elevators. The results of this series of experiments showed that the RMSE of the ZUPT-based INS aided by the hybrid altimeter outperformed the RMSE of the standalone ZUPT-based INS by 91%. When compared to the RMSE of the ZUPT-based INS aided by the barometer vs. the hybrid altimeter, in the latter case the accuracy was increased by 41% (0.15 ????). The primary residual error sources, in our opinion, contributing to the vertical errors of the ZUPT-based INS aided by the hybrid altimeter are the underestimate of stair height and the false alarm of stair detection of the ultrasonic altimeter.

The impact of annealing temperature and the duration on the dielectric properties of atomic-layer-deposited (ALD) 5 mol% Y-doped HfO 2 capacitors have been examined. Besides the ferroelectric behavior of the capacitor over an annealing temperature of $500^{\circ}\mathrm{C}$ for short period, the appearance of ferroelectricity has been obtained at $400^{\circ}\mathrm{C}$ when annealed over 5 min. A fairly nice ferroelectric property with a remanent polarization P r of 12 $\mu$/cm2 after wake-up process has been obtained.

We present a method to identify and compensate systematic errors in the ZUPT-aided pedestrian inertial navigation. We considered two main categories of systematic errors resulting in an underestimate of the length of the trajectory and a drift in the heading of the trajectory. In this study, we identified the dominant factors resulting in the trajectory length and heading errors to be residual velocity during the stance phase and g-sensitivity error of the gyroscopes, respectively. Magnetic motion tracking system was used to record the velocity of the foot during the stance phase. Rate table, tilt table, and shaker were used to calibrate the IMU g-sensitivity. After compensation, a more than $6\times$ systematic error reduction was demonstrated from 3.24m to 0.50m during a 100m straight line trajectory. To the best of our knowledge, this study is the first attempt to reduce the systematic errors in the ZUPT-aided pedestrian inertial navigation algorithmically, without adding extra sensing modalities.

This paper presents a miniature 50 mm3 inertial measurement unit (IMU) implemented using a folded microelectromechanical systems (MEMS) process. The approach is based on wafer-level fabrication of high aspect-ratio single-axis sensors interconnected by flexible hinges and folded into a 3-D configuration, like a silicon Origami [1] . Two different materials for flexible hinges have been explored, including photo-definable polyimide and parylene-C. We report, for the first time, an IMU prototype with seven operational sensors: three accelerometers, three gyroscopes, and a prototype of a reference clock. This paper concludes with the results of experimental characterization of inertial sensors demonstrating the feasibility of the proposed approach for a compact IMU. [2016-0267]

BackgroundUnplanned readmission of a hospitalized patient is an extremely undesirable outcome as the patient may have been exposed to additional risks. The rates of unplanned readmission are, therefore, regarded as an important performance indicator for the medical quality of a hospital and healthcare system. Identifying high-risk patients likely to suffer from readmission before release benefits both the patients and the medical providers. The emergence of machine learning to detect hidden patterns in complex, multi-dimensional datasets provides unparalleled opportunities to develop efficient discharge decision-making support system for physicians.Methods and FindingsWe used supervised machine learning approaches for ICU readmission prediction. We used machine learning methods on comprehensive, longitudinal clinical data from the MIMIC-III to predict the ICU readmission of patients within 30 days of their discharge. We have utilized recent machine learning techniques such as Recurrent Neural Networks (RNN) with Long Short-Term Memory (LSTM), by this we have been able incorporate the multivariate features of EHRs and capture sudden fluctuations in chart event features (e.g. glucose and heart rate) that are significant in time series with temporal dependencies, which cannot be properly captured by traditional static models, but can be captured by our proposed deep neural network based model. We incorporate multiple types of features including chart events, demographic, and ICD9 embeddings. Our machine learning models identifies ICU readmissions at a higher sensitivity rate (0.742) and an improved Area Under the Curve (0.791) compared with traditional methods. We also illustrate the importance of each portion of the features and different combinations of the models to verify the effectiveness of the proposed model.ConclusionOur manuscript highlights the ability of machine learning models to improve our ICU decision making accuracy, and is a real-world example of precision medicine in hospitals. These data-driven results enable clinicians to make assisted decisions within their patient cohorts. This knowledge could have immediate implications for hospitals by improving the detection of possible readmission. We anticipate that machine learning models will improve patient counseling, hospital administration, allocation of healthcare resources and ultimately individualized clinical care.

Capacitance extraction of ferroelectric HfO2 capacitors was characterized at a frequency of 1 GHz. By applying a bias voltage in the non-switching region of the ferroelectric HfO2 films, a varactor operation was confirmed. Introduction The ferroelectric HfO2 layer has attracted attraction in CMOS and memory applications due to its scaling ability and process compatibility. Generally, ferroelctric capacitors show increase in the capacitance near the coercive field. By setting a proper bias to the ferroelectric capacitors, they can work as varactors under non-switching mode. As there is an increasing demand on-chip varactors for monolithic microwave ICs (MMICs) [1,2]. In this research, we measured the capacitance of the ferroelectric HfO2 capacitors at high frequency and confirmed the capacitance control. Measruements were done under on-wafer probing system in the frequency range of 10 MHz to 1 GHz [3]. Experiments Figure 1 shows the schematic cross-section of ferroelectric HfO2 capacitors. A 1 mm plasma SiO2 layer was first deposited on a high-resistive Si wafer f. A 12-nm-thick 5 mol% Y-doped HfO2 film were deposteid by atomic layer deposition (ALD). The top and bottom electrode were both W deposited by sputtering and patterned by reactive ion etching (RIE). Annealing to transform the HfO2 layer into ferroelectric pahse was conducted at 500 oC. Metal contacts of Au/Ni/Ti were deposited by thermal evaporation. Results and discussions Capacitance-voltage measurement taken from LCR meter at 10 kHz is shown in fig. 2. After polling process, the capacitance can be tuned by 32 % by controlling the bais voltage in the non-switching region. The capacitance values under different bias voltage, extracted from the S-parameters of capacitors with proper calibration patterns, are shown in fig. 3. Although the capacitance tuning was narrow compared to those obtained by the LCR meter, the varactor operation was confirmd with ferroelectric HfO2 capacitors. Conclusion A varactor operation in ferroelectric HfO2 capacitor at 1 GHz was confirmed. References [1] N. Setter, et al., J. Appl. Phys. 100, 051606 (2006) [2] A. Vorobiev, et al., Appl. Phys. Lett. 83, 3144 (2003) [3] K. Lee, et al., IEEE Trans. Microw. Theory Tech., vol. 54, no. 12, pp. 4141-4148 (2006) Figure 1

This paper presents a study on dynamics of a dual-mass MEMS vibratory gyroscope in presence of fabrication imperfections and reports a method for precision electrostatic frequency tuning of the operational modes. A number of multi-mass MEMS gyroscopes have emerged in recent years pursuing different goals, such as dynamically balanced structure, increased bandwidth, and dynamic amplification. Along with many perceived advantages of multi-mass devices, several challenges associated with mode-matching in a system with increased number of degrees-of-freedom (DOF) have to be considered. This work shows that it is possible to apply the DC tuning techniques, similar to tuning a conventional single-mass gyroscope, to achieve the precision tuning in a dual-mass sensor, without losing advantages of increased DOF of the system. The presented frequency trimming technique is based on assessing the modes mismatch and cross-coupling between modes by means of fitting the experimental frequency response curves to the analytical solutions of the dual-mass system in presence of imperfections. The tuning algorithm involves two steps. First, the stiffness mismatch along the two axes and the anisoelasticity angles α and β are identified, then the tuning DC voltages for modification of diagonal, off-diagonal, and coupling terms in the stiffness matrix are chosen. The method of electrostatic tuning was validated through the experimental characterization of a dual-mass dynamically amplified gyroscope, where the coupling between the two operational modes was minimized and frequency split was reduced from 26 Hz down to 50 mHz, resulting in 17.5× increase in the gyroscope scale factor and significantly improved noise characteristics. The presented electrostatic compensation method is suitable for both off-line and on-line calibration.

This paper reports an approach for co-fabrication of silicon-on-insulator (SOI) sensors with low-resistance vertical electrical interconnects in thick (up to $600~\mu \text{m}$ ) wafers. The thru-wafer interconnects double-sided (TWIDS) process is based on bottom-up seedless copper electroplating, and allows for voids-free features and high aspect ratio (wafer thickness to copper diameter ratio of 10:1). This work describes the design trade-offs, process flow, and characterization of interconnects. TWIDS technology is compatible with a standard SOI micro-electro-mechanical systems (MEMS) fabrication process and is applicable for micro sensors, such as accelerometers, gyroscopes, resonators, and RF MEMS devices, as well as for the 3-D MEMS assemblies. As a demonstration of potential applications, miniature toroidal ring gyroscopes were fabricated using the TWIDS process. The experimental characterization showed that the low-resistance interconnects with low parasitic losses are suitable for integration with capacitive-detection sensors. In addition, the mechanical stability of the interconnects is discussed in this paper, and a method to enhance structural rigidity by means of filling the insulating gaps with Parylene C is demonstrated. [2017-0179]

BACKGROUND. Cytotoxic T lymphocyte–mediated (CTL-mediated) severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), are rare but life-threatening adverse reactions commonly induced by drugs. Although high levels of CTL-associated cytokines, chemokines, or cytotoxic proteins, including TNF-α and granulysin, were observed in SJS-TEN patients in recent studies, the optimal treatment for these diseases remains controversial. We aimed to evaluate the efficacy, safety, and therapeutic mechanism of a TNF-α antagonist in CTL-mediated SCARs. METHODS. We enrolled 96 patients with SJS-TEN in a randomized trial to compare the effects of the TNF-α antagonist etanercept versus traditional corticosteroids. RESULTS. Etanercept improved clinical outcomes in patients with SJS-TEN. Etanercept decreased the SCORTEN-based predicted mortality rate (predicted and observed rates, 17.7% and 8.3%, respectively). Compared with corticosteroids, etanercept further reduced the skin-healing time in moderate-to-severe SJS-TEN patients (median time for skin healing was 14 and 19 days for etanercept and corticosteroids, respectively; P = 0.010), with a lower incidence of gastrointestinal hemorrhage in all SJS-TEN patients (2.6% for etanercept and 18.2% for corticosteroids; P = 0.03). In the therapeutic mechanism study, etanercept decreased the TNF-α and granulysin secretions in blister fluids and plasma (45.7%–62.5% decrease after treatment; all P < 0.05) and increased the Treg population (2-fold percentage increase after treatment; P = 0.002), which was related to mortality in severe SJS-TEN. CONCLUSIONS. The anti–TNF-α biologic agent etanercept serves as an effective alternative for the treatment of CTL-mediated SCARs. TRIAL REGISTRATION. ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01276314","term_id":"NCT01276314"}}NCT01276314. FUNDING. Ministry of Science and Technology of Taiwan.

This paper presents a study on the structural rigidity of an Inertial Measurement Unit (IMU) implemented using the Folded MEMS approach. For such folded structures, environmental survivability and stability is a natural concern. We investigated IMUs of 35 mm3 (small) and 130 mm3 (medium) in volume, in the shape of a cube and a pyramid, and considered the reinforcement methods, including epoxy, eutectic solder, and silicon welding. Experimental characterization of a medium cube with eutectic reinforcement showed the maximum tilt of 0.2 mrad on the cube's sidewalls under temperature variation 25°C–90°C and the tilt of 0.2mrad under 10Hz to 20kHz vibration. An IMU error model was implemented, with the target sensors performance of tactical-grade, using in-run bias stability and scale factor (SF) stability for gyroscope (1°/hr, 100ppm) and for accelerometer (100µg, 100ppm), and a pre-defined trajectory with 122s flight time. The 0.2 mrad misalignment for the medium eutectic-soldered cube corresponded to a Circular Error Probable (CEP) rate of 1.25 nmi/hr, and a typical tactical grade IMU corresponded to CEP rate ≤1nmi/hr. We also concluded that the 35mm3 eutectic-bonding reinforced cubes will survive the mechanical shock under 10,000g, while silicon welding reinforced cubes of 35 mm3 would survive the shocks of 20,000g.

This paper reports a miniature Inertial Measurement Unit (IMU) implemented using a folded MEMS approach which allows for integration of high performance sensors, while providing a low cross-talk between the components. Foldable Si structures are manufactured on a wafer-level using MEMS techniques, co-fabricated or integrated with single-axis inertial sensors and then folded into a 3D configuration, forming the complete IMU. Electrical signals from the sensors on sidewalls of the IMU Cube are transferred through the dense network of metal traces on parylene, thus enabling the integration with signal processing electronics. For the first time, we characterized cross-talk between sensors on a folded 3D IMU. The experimental results provided an evidence that the folded IMU process is advantageous to a single-die approach, showing a lower Angle Random Walk (ARW) of the gyroscopes when operated simultaneously on different sidewalls of the IMU Cube.

In recent years, micro lens arrays have played a crucial role in optical illumination systems. The function of micro lens arrays (MLAs) is to create a uniform light intensity or shape the light profile. Polymers that are commonly used as MLAs have several advantages, such as cost effectiveness, light weight, and easy formation. In general, the ultra-precision diamond-turning technique and plastic injection molding technique have been combined to fabricate MLAs with polymer materials. However, residual stress and non-balance injection pressure are produced on MLAs during injecting processing. Therefore, this paper presents the fabrication of MLAs using a direct molding method (DMM). The STAVAX with electroless nickel coating and PMMA were used as the mold and polymer preform, respectively. First, a mold of MLA with 100% filling factor was fabricated using the ultra-precision diamond-turning technique. A high filling factor can decrease the non-effective area of the MLA in an optical system. Subsequently, an MLA was formed on the PMMA surface using DMM processing. This paper shows the DMM process parameters, including molding temperature, molding force, and cooling rate. Moreover, the profile of the MLA was measured using a laser confocal microscope. Finally, a high filling factor MLA with a diameter of 11.5 mm, and lenses with a height of 8.5 μm and a radius of 470 μm were formed on PMMA.

This study developed a precise hybrid optical lens (PHOL) that included polymer and glass materials. Although glass offers superior anti-thermal, anti-environmental, anti-scraped corrosion resistance and optical properties than polymer materials, it is difficult to fabricate glass materials. Therefore, it is difficult to obtain a high-accuracy aspheric glass lens. This paper presents the fabrication of a PHOL that combined aspheric polymer and glass bases using a glass-molding technique. The PHOL can be used to reduce aberration errors in optical systems using two materials. The PHOL maintains the advantages of glass materials, and the cost of aspheric polymer is lower than that of the aspheric glass layer. Thermosetting polymer was used as the aspheric part in this study. Compared to UV-curable polymer, thermosetting polymer has higher thermal stability, and the molds are not limited by glass materials, which must be transmissible by UV light. First, a glass sphere lens was used as a base of the PHOL. Subsequently, the ultra-precise diamond turning technique was used to fabricate the mold with an aspheric profile. During the molding process, the thermosetting polymer was formed into an aspheric layer and covered on the glass base. The PHOL of 11.2 mm in diameter was obtained using controlled cooling. Finally, the surface accuracy (PV) of the PHOL was less than 0.5μm, has been successfully fabricated in this study.

In this paper, we discuss the primary sources of frequency splits in degenerate mode Toroidal Ring Gyroscope (TRG) with isotropic concentric rings suspension. We show that operation in the n=3 “wineglass mode” might be preferable for prioritized device symmetry. We demonstrate that by means of structural design it is possible to achieve a desired order of wineglass modes, critical for vibration immunity, and potentially for improved performance of miniature devices. Mode-ordering is accomplished by a proper choice of a number of rings in the suspension and an angle between the spokes connecting the rings. The method of mode-ordering is confirmed through experimental characterization of 2.8 mm diameter TRG prototypes fabricated in and single crystal silicon.

This paper reports a new approach for fabrication of high-aspect ratio low resistance vertical interconnects, providing an electrical interface between the front-side and the backside of the Silicon-on-Insulator (SOI) wafer. The method of Thru-Wafer Interconnects for Double-Sided (TWIDS) fabrication of MEMS is based on seedless copper electroplating, and allows for voids free features and high aspect ratio (copper diameter to wafer thickness ratio is 10∶1). We introduced the fabrication sequence, implemented and characterized prototypes of a MEMS toroidal ring gyroscope with thru-wafer interconnects, thus illustrating the process feasibility. Furthermore, the critical issue of mechanical stability in air-gap interconnect structures under 15,000 g shock was investigated using 3D Finite Element Analysis (FEA) models. Our simulations revealed that a partial filling the gaps with Parylene C allows for 1.55x improvement in mechanical stability without a significant increase in via parasitic capacitance values.

Panax notoginseng was used as the medium for lactic acid bacteria fermentation to manufacture product with antihepatocarcinoma activity. The fermentation broth prepared in a 250 mL Erlenmeyer flask was found to possess antiproliferation activity against hepatoma Hep3B cells. At the dosage of 500 microg/mL, the viability of hepatoma Hep3B cells was approximately 2.2%. When the fermentation was scaled up to a 6.6 L fermenter, it was found that the fermentation broth produced at 37 degrees C for 2 days showed the highest antihepatoma activity. Animal study revealed that when Hep3B implanted SCID mice were treated with 1000 mg/kg BW/day of the fermentation broth, tumor volume and tumor weight were reduced approximately 60% as compared to the negative control group. HPLC analyses showed that saponins in P. notoginseng including notoginsenoside R(1) and ginsenosides Rg(1), Rb(1), Rd, and Rh(4) decreased, but ginsenosides Rh(1) and Rg(3) increased during fermentation. LC-MS/MS revealed that the minor saponins ginsenoside F(1), protopanaxatriol, and notoginseng R(2) also exist in the fermentation product. It appears that ginsenoside Rg(3), ginsenoside Rh(1), and protopanaxatriol are possibly responsible for the enhanced antihepatocarcinoma activity of the P. notoginseng fermentation broth.

Vibrating polysilicon micromechanical ring resonators, using a unique extensional wine-glass-mode shape to achieve lower impedance than previous UHF resonators, have been demonstrated at frequencies as high as 1.2 GHz with a Q of 3,700, and 1.52 GHz with a Q of 2,800. The 1.2-GHz resonator exhibits a measured motional resistance of 1 MOmega with a dc-bias voltage of 20 V, which is 2.2 times lower than the resistance measured on radial contourmode disk counterparts at the same frequency. The use of larger rings offers a path toward even lower impedance, provided the spurious modes that become more troublesome as ring size increases can be properly suppressed using methods described herein. With spurious modes suppressed, the high-Q and low-impedance advantages, together with the multiple frequency on-chip integration advantages afforded by capacitively transduced micromechanical resonators, make this device an attractive candidate for use in the front-end RF filtering and frequency generation functions needed by wireless communication devices.

In this paper, we present a novel 128/64 point fast Fourier transform (FFT)/ inverse FFT (IFFT) processor for the applications in a multiple-input multiple-output orthogonal frequency-division multiplexing based IEEE 802.11n wireless local area network baseband processor. The unfolding mixed-radix multipath delay feedback FFT architecture is proposed to efficiently deal with multiple data sequences. The proposed processor not only supports the operation of FFT/IFFT in 128 points and 64 points but can also provide different throughput rates for 1-4 simultaneous data sequences to meet IEEE 802.11n requirements. Furthermore, less hardware complexity is needed in our design compared with traditional four-parallel approach. The proposed FFT/IFFT processor is designed in a 0.13-mum single-poly and eight-metal CMOS process. The core area is 660times2142 mum2 , including an FFT/IFFT processor and a test module. At the operation clock rate of 40 MHz, our proposed processor can calculate 128-point FFT with four independent data sequences within 3.2 mus meeting IEEE 802.11n standard requirements

Fragmented QRS (fQRS) is an important and noninvasive marker for evaluating myocardial scar in patients with coronary artery disease, which is defined as additional spikes within the QRS wave. It is not easy to detect the fQRS accurately because of a variety of fQRS morphologies. This study is to analyze the high-frequency (HF) potentials of fQRS complexes using a continuous wavelet transform-based method in patients with myocardial infarction (MI). The HF parameter is defined as the root-mean-square (RMS) value of wavelet coefficients at the central frequencies of 100Hz, 150Hz, 200Hz, or 250Hz further normalized by the RMS value of the entire QRS complex, which is defined as the HF ratio. There were 76 MI patients and 43 Normal subjects recruited in this study. All of the ECG recordings were obtained from the PTB Diagnostic ECG Database including the conventional 12-lead and Frank XYZ lead ECGs. A signal averaging technology was adopted to reduce the background noise. The fQRS complexes were defined by the presence of an additional R wave, or notching in the nadir of the S wave, notching of the R wave, or the presence of more than one R prime. All of the mean HF ratios of the fQRS complexes are significantly larger than those of the non-fQRS complexes (p

In this paper, we present a novel 128-point FFT/IFFT processor for ultrawideband (UWB) systems. The proposed pipelined FFT architecture, called mixed-radix multipath delay feedback (MRMDF), can provide a higher throughput rate by using the multidata-path scheme. Furthermore, the hardware costs of memory and complex multipliers in MRMDF are only 38.9% and 44.8% of those in the known FFT processor by means of the delay feedback and the data scheduling approaches. The high-radix FFT algorithm is also realized in our processor to reduce the number of complex multiplications. A test chip for the UWB system has been designed and fabricated using 0.18-/spl mu/m single-poly and six-metal CMOS process with a core area of 1.76/spl times/1.76 mm/sup 2/, including an FFT/IFFT processor and a test module. The throughput rate of this fabricated FFT processor is up to 1 Gsample/s while it consumes 175 mW. Power dissipation is 77.6 mW when its throughput rate meets UWB standard in which the FFT throughput rate is 409.6 Msample/s.

This paper presents an 8192-point FFT processor for DVB-T systems, in which a three-step radix-8 FFT algorithm, a new dynamic scaling approach, and a novel matrix prefetch buffer are exploited. About 64 K bit memory space can be saved in the 8 K point FFT by the proposed dynamic scaling approach. Moreover, with data scheduling and pre-fetched buffering, single-port memory can be adopted without degrading throughput rate. A test chip for 8 K mode DVB-T system has been designed and fabricated using 0.18-/spl mu/m single-poly six-metal CMOS process with core area of 4.84 mm/sup 2/. Power dissipation is about 25.2 mW at 20 MHz.

A simple processing technology for oxide confined vertical-cavity surface-emitting lasers (VCSELs) fabrication is reported in this article. Results of the burn-in test up to the present-day show that the high temperature lifetime of the fabricated devices exceeded 70:00 h. The eye diagrams show that the devices can be modulated up to 10 Gbps.

In order to achieve noise figure smaller than 1dB, the GNSS receivers require external LNA, which adds area, cost and current consumption. A 28nm CMOS sub-1dB NF 9mW GNSS receiver is presented, requiring no external components. This work takes advantage of symmetry in performance between NMOS and PMOS at 28nm node and demonstrates that low NF is possible on advanced CMOS at low power levels, with proper design of on-chip matching components.

MEMS-based capacitively-transduced microme- chanical disk resonators have been demonstrated that dispense with conventional high voltage source direct dc-biasing and in- stead use stored charge on their resonant structures to achieve equivalent performance. In particular, a 103-MHz microme- chanical contour-mode disk resonator has been demonstrated with the same Q (~25,000) and series motional resistance when charge-biased as when biased via a dc voltage source directly connected to its resonant structure. For a stand-alone charge-biased resonator, leaky discharging of the resonant structure in vacuum attenuates the output signal by 3dB after 900s. If a 0.18μF capacitor is charged and attached to the floating resonant structure, the resonator can operate for more than 8.5 days before its signal is attenuated by 3dB, which clearly illus- trates the long-term efficacy of this charge-biasing approach. Frequency shifts caused by discharge-induced bias shifts are less than 2.5 ppm per hour with charged 0.18μF capacitor, making plausible a "charge-and-refresh" operating mode with one-hour (or longer) refresh intervals.

Notching and low-velocity coupling design strategies are described and demonstrated that yield the first UHF vibrating micromechanical hollow-disk ring mixer-filters with IF bandwidths down to 0.05%, while still retaining reasonable passband shapes. Specifically, a 423-MHz mixer-filter, comprised of two mechanically coupled resonators exhibiting Q's in excess of 10,000, has been successfully demonstrated with a flat passband bandwidth of only 202 kHz. Like a previous 34-MHz mixer-filter based on clamped-clamped beam resonators, the much higher frequency device of this work is capable of performing both mixing (via capacitive transducer nonlinearity) from an RF frequency down to its IF passband centered at 423 MHz, then very small percent bandwidth filtering, e.g., to remove unwanted interferers in the receive path of a communication handset. The percent bandwidths demonstrated here are small enough to make possible channel-selection much earlier in a receive path chain, which could then greatly enhance the robustness and battery lifetime of future wireless transceivers.

A DVB-T/H baseband receiver with multi-stage power control, 2D linear channel equalizer, synchronizer, 2/4/8k-point FFT, and Viterbi/RS decoder is implemented in 0.18mum CMOS. At the highest data rate of 31.67Mb/s, it overcomes 70Hz Doppler frequency and consumes 250mW with a die size of 6.9 times 5.8mm2

Location-dependent, bidirectional laser trimming of the resonance frequencies of vibrating micromechanical resonators is demonstrated in steps as small as 21 ppm over it range of 20,200 ppm, and with targeting measures that suppress unwanted variations in Q and series motional resistance. Specifically, geometrically symmetrical laser targeting is shown to be instrumental in preserving high Q on the micro-scale, much more so than on the macro-scale. A semi-empirical model is used to model the trimming process and to identify the laser trim locations that most efficiently attain a desired shift in frequency with minimal Q reduction. Different micromechanical resonator types are trimmed to demonstrate the versatility of the technique, including a clamped-clamped beam and a wine glass disk.

A vibrating polysilicon micromechanical "hollow-disk" ring resonator obtained by removing quadrants of material from a solid disk resonator, but purposely leaving intact beams of material to non-intrusively support the structure, has been demonstrated in several vibration modes spanning frequencies from HF (24.4 MHz), to VHF (72.1MHz), to UHF (1.169 GHz), with Q's as high as 67,519, 48,048, and 5,846, respectively. Furthermore, the use of notched support attachments closer to actual extensional ring nodal points raises the Q to 14,603 at 1.2 GHz, which is the highest yet achieved past 1 GHz, and which clearly illustrates the utility of notching for substantially higher Q. At 1.2 GHz, a combination of high Q and larger capacitive transducers allows the notched version to achieve an R/sub x/ of only 282 k/spl Omega/, which is 12X smaller than achieved by previous pure polysilicon surface-micromachined solid disk resonators in the GHz range.

A simple processing technology for oxide confined vertical-cavity surface-emitting lasers fabrication is reported in this article. Results of the burn-in test up to the present-day show that the high temperature lifetime of the fabricated devices exceeded 3300 hours. The eye diagrams show that the devices can be modulated up to 10 Gbps.

In this paper, combined finite element simulations and experimental measurements are used to study the dynamic response of fluid-loaded piezoelectric element for phased array design. An efficient and robust numerical methodology for 3D coupled structural acoustic model is developed. A confocal Fabry-Perot laser interferometer is used to measure the surface response. Comparisons are made between numerical results and experimental results. Important features in the transducer design such as radiation patterns in the fluid domain, as well as the electromechanical behavior of the transducer, are evaluated.

High-speed vertical-cavity surface-emitting lasers that could be modulated up to 10 Giga-bit-per-second (Gbps) were accomplished by using additional proton implantation to reduce the parasitic capacitance. The eye diagram of the implanted device shows a noticeable improvement when compared with those devices without implantation. In contrast to previous reports, moreover, the output power-current-voltage (L-I-V) characteristics of the fabricated devices in this study show excellent consistency between before and after implantation. The high-temperature lifetime of devices fabricated with a similar process has already exceeded 8100 h up to the present day.