The Optimal Selection of Mother Wavelet Function and Decomposition Level for Denoising of DCG Signal.

The aim of this paper is to find the optimal mother wavelet function and wavelet decomposition level when denoising the Doppler cardiogram (DCG), the heart signal obtained by the Doppler radar sensor system. To select the best suited mother wavelet function and wavelet decomposition level, this paper presents the quantitative analysis results. Both the optimal mother wavelet and decomposition level are selected by evaluating signal-to-noise-ratio (SNR) efficiency of the denoised signals obtained by using the wavelet thresholding method. A total of 115 potential functions from six wavelet families were examined for the selection of the optimal mother wavelet function and 10 levels (1 to 10) were evaluated for the choice of the best decomposition level. According to the experimental results, the most efficient selections of the mother wavelet function are "db9" and "sym9" from Daubechies and Symlets families, and the most suitable decomposition level for the used signal is seven. As the evaluation criterion in this study rates the efficiency of the denoising process, it was found that a mother wavelet function longer than 22 is excessive. The experiment also revealed that the decomposition level can be predictable based on the frequency features of the DCG signal. The proposed selection of the mother wavelet function and the decomposition level could reduce noise effectively so as to improve the quality of the DCG signal in information field.

Virtual Point Removal for Large-Scale 3D Point Clouds with Multiple Glass Planes.

Large-scale 3D point clouds (LS3DPCs) captured by terrestrial LiDAR scanners often include virtual points which are generated by glass reflection. The virtual points may degrade the performance of various computer vision techniques when applied to LS3DPCs. In this paper, we propose a virtual point removal algorithm for LS3DPCs with multiple glass planes. We first estimate multiple glass regions by modeling the reliability with respect to each glass plane, respectively, such that the regions are assigned high reliability when they have multiple echo pulses for each emitted laser pulse. Then we detect each point whether it is a virtual point or not. For a given point, we recursively traverse all the possible trajectories of reflection, and select the optimal trajectory which provides a point with a similar geometric feature to a given point at the symmetric location. We evaluate the performance of the proposed algorithm on various LS3DPC models with diverse numbers of glass planes. Experimental results show that the proposed algorithm estimates multiple glass regions faithfully and detects the virtual points successfully. Moreover, we also show that the proposed algorithm yields a much better performance of reflection artifact removal compared with the existing method qualitatively and quantitatively.

Vital-Signs Detector Based on Frequency-Shift Keying Radar.

A frequency-shift keying (FSK) radar in the 2.45-GHz band is proposed for highly accurate vital-signs detection. The measurement accuracy of the proposed detector for the heartbeat is increased by using the cross-correlation between the phase differences of signals at two frequencies used by the FSK radar, which alternately transmits and receives the signals with different frequencies. Two frequencies-2.45 and 2.5 GHz-are effectively discriminated by using the envelope detection with the frequency control signal of the signal generator in the output waveform of the FSK radar. The phase difference between transmitted and received signals at each frequency is determined after calibrating the I / Q imbalance and direct-current offset using a data-based imbalance compensation algorithm, the Gram-Schmidt procedure, and the Pratt method. The absolute-distance measurement results for a human being show that the vital signs obtained at each frequency using the proposed FSK radar have a cross-correlation. The heartbeat detection results for the proposed FSK radar at a distance of < 2.4 m indicate a reduction in the error rate and an increase in the signal-to-noise ratio compared with those obtained using a single operating frequency.

Is preeclampsia itself a risk factor for the development of metabolic syndrome after delivery?

OBJECTIVE: This study aimed to determine the association between preeclampsia and the postpartum development of metabolic syndrome based on the pre-pregnancy status. METHODS: Korean women who delivered their first child between January 1, 2011, and December 31, 2012, were enrolled. All subjects underwent a national health screening examination conducted by the National Health Insurance Corporation 1 or 2 years prior to their first delivery and within 2 years after their first delivery. RESULTS: Among the 49,065 participants, preeclampsia developed in 3,391 participants (6.9%). The prevalence of metabolic syndrome was higher postpartum in women with preeclampsia than in those without preeclampsia (4.9% vs. 2.7%, respectively, P<0.001). Through the pre-pregnancy to postpartum period, women with preeclampsia had a greater increase in gestational weight retention, body mass index, waist circumference, systolic blood pressure, and triglyceride levels and a greater decrease in high-density lipoprotein cholesterol levels than women without preeclampsia. Preeclampsia was associated with an increased risk of the postpartum development of metabolic syndrome in women without pre-pregnancy metabolic syndrome (odds ratio, 1.28; 95% confidence interval, 1.05-1.56). However, preeclampsia was not associated with postpartum metabolic syndrome in women with pre-pregnancy metabolic syndrome or 2 components of metabolic syndrome. CONCLUSION: In this study, preeclampsia was associated with the postpartum development of metabolic syndrome in women without pre-pregnancy metabolic syndrome. However, the effects were attenuated by predisposing risk factors in the pre-pregnancy period.

Glass Reflection Removal Using Co-Saliency-Based Image Alignment and Low-Rank Matrix Completion in Gradient Domain.

The images taken through glass often capture a target transmitted scene as well as undesired reflected scenes. In this paper, we propose a novel reflection removal algorithm using multiple glass images taken from slightly different camera positions. We first find co-saliency maps for input multiple glass images based on the center prior assumption, and then align multiple images reliably with respect to the transmitted scene by selecting feature points with high co-saliency values. The gradients of the transmission images are consistent while the gradients of the reflection images are varying across the aligned multiple glass images. Based on this observation, we compute gradient reliability such that the pixels belonging to consistent salient edges of the transmission image are assigned high reliability values. We restore the gradients of the transmission images and suppress the gradients of the reflection images by formulating a low-rank matrix completion problem in gradient domain. Finally, we reconstruct desired transmission images from the restored transmission gradients. Experimental results show that the proposed algorithm removes the reflection artifacts from glass images faithfully and outperforms the existing methods on challenging glass images with diverse characteristics.

The novel, potent and highly selective 5-HT4 receptor agonist YH12852 significantly improves both upper and lower gastrointestinal motility.

BACKGROUND AND PURPOSE: 5-HT4 receptor agonists have been shown to be effective at treating various gastrointestinal tract disorders. However, a lack of selectivity against off-targets has been a limiting factor for their clinical use. EXPERIMENTAL APPROACH: The binding affinity and selectivity of YH12852 for human 5-HT4(a) receptor in CHO-K1 cells were evaluated using radioligand binding assays, and agonistic activity was assessed using a ß-lactamase reporter system. Contractile activity and propulsive motility were measured in the guinea pig isolated distal colon. Its prokinetic effect on the gastrointestinal tract was evaluated in guinea pigs, dogs and monkeys. Its tissue distribution was evaluated in rats. KEY RESULTS: YH12852 exhibited high affinity and potency for human recombinant 5-HT4(a) receptor with high selectivity over other 5-HT and non-5-HT receptors, ion channels, enzymes and transporters. YH12852 induced contractions and increased propulsive motility in guinea pig isolated colon. These effects were abolished by the 5-HT4 receptor antagonist GR113808. YH12852 increased defecation more effectively than prucalopride in guinea pigs and dogs and improved gastric emptying more effectively than mosapride in guinea pigs, dogs and monkeys. YH12852 was highly distributed to the gastrointestinal tract as the target organ. CONCLUSION AND IMPLICATIONS: The high in vitro potency and selectivity of YH12852 for 5-HT4 receptor translated into potent in vivo efficacy with good tolerability. YH12852 significantly improved both upper and lower bowel motility in the animal models tested and has the potential to address considerable unmet needs in patients with functional constipation, gastroparesis or both.

Polymeric Inverse Glasses for Development of Noniridescent Structural Colors in Full Visible Range.

Amorphous colloidal array with short-range order displays noniridescent structural colors due to the isotropic nature of the colloidal arrangement. The low angle dependence renders the colloidal glasses, which is promising for various coloration applications. Nevertheless, the colloidal glasses are difficult to develop red structural color due to strong cavity-like resonance from individual particles in the blue region. To suppress the cavity mode and develop the colors in the full visible range, we prepare inverse glasses composed of amorphous array of air cavities with short-range order. To produce the structures in a simple and reproducible manner, monodisperse silica particles are dispersed in a photocurable resin of poly(ethylene glycol) dimethacrylate (PEGDMA) at a volume fraction of 0.3. The particles spontaneously form the amorphous array with short-range order, which is rapidly captured in polymeric films by photopolymerization of the resin. Selective removal of silica particles from the polymerized resin leaves behind amorphous array of air cavities. The inverse glasses display structural colors with negligible backscattering in blue due to short optical path and low index in each cavity. Therefore, the colors can be tuned in full visible range by simply controlling the cavity size. The photocurable suspensions of silica particles can be patterned by photolithography, which enables the production of freestanding films containing patterned inverse glasses with noniridescent structural colors.

Microfluidic Design of Magnetoresponsive Photonic Microcylinders with Multicompartments.

Colloidal photonic structures have been designed to have granular format to use them for paint pigments, encoded carriers, and display pixels. However, conventional approaches only provide spherical or discoid shapes, restricting their applications. Cylindrical granules with fan-shaped compartments in the cross section are appealing for microcarriers with abundant optical codes and active display pigments for color switching. In this work, a stratified laminar flow of concentrated silica particles is employed, formed in a cylindrical microchannel, to produce cylindrical photonic microparticles with multiple compartments. To accomplish this, a microfluidic device is designed to have one cylindrical main channel connected with four branch channels. Four different photocurable suspensions are independently injected through the branches to form quarter-cylindrically compartmentalized streams in the main channel. Local ultraviolet irradiation on the main channel polymerizes the suspension, thereby forming cylindrical microparticles with four compartments. In each compartment, silica particles form ordered array which develops particle size-dependent structural color. Therefore, different colors can be incorporated into single microcylinder by employing different sizes of silica particles. Moreover, one of the compartments can be rendered to be magnetoresponsive by embedding aligned magnetic particles, which enables the remote control of microcylinder orientation and therefore the switching of structural colors.

Video deraining and desnowing using temporal correlation and low-rank matrix completion.

A novel algorithm to remove rain or snow streaks from a video sequence using temporal correlation and low-rank matrix completion is proposed in this paper. Based on the observation that rain streaks are too small and move too fast to affect the optical flow estimation between consecutive frames, we obtain an initial rain map by subtracting temporally warped frames from a current frame. Then, we decompose the initial rain map into basis vectors based on the sparse representation, and classify those basis vectors into rain streak ones and outliers with a support vector machine. We then refine the rain map by excluding the outliers. Finally, we remove the detected rain streaks by employing a low-rank matrix completion technique. Furthermore, we extend the proposed algorithm to stereo video deraining. Experimental results demonstrate that the proposed algorithm detects and removes rain or snow streaks efficiently, outperforming conventional algorithms.

Bit allocation algorithm with novel view synthesis distortion model for multiview video plus depth coding.

An efficient bit allocation algorithm based on a novel view synthesis distortion model is proposed for the rate-distortion optimized coding of multiview video plus depth sequences in this paper. We decompose an input frame into nonedge blocks and edge blocks. For each nonedge block, we linearly approximate its texture and disparity values, and derive a view synthesis distortion model, which quantifies the impacts of the texture and depth distortions on the qualities of synthesized virtual views. On the other hand, for each edge block, we use its texture and disparity gradients for the distortion model. In addition, we formulate a bit-rate allocation problem in terms of the quantization parameters for texture and depth data. By solving the problem, we can optimally divide a limited bit budget between the texture and depth data, in order to maximize the qualities of synthesized virtual views, as well as those of encoded real views. Experimental results demonstrate that the proposed algorithm yields the average PSNR gains of 1.98 and 2.04 dB in two-view and three-view scenarios, respectively, as compared with a benchmark conventional algorithm.

Microfluidic molding of photonic microparticles with engraved elastomeric membranes.

A microfluidic approach to prepare photonic microparticles by repeated molding of photocurable colloidal suspension is reported. An elastomeric membrane with negative relieves which vertically separates two microfluidic channels is integrated; bottom channel is used for suspension flow, whereas water-filled top channel is used for pneumatic actuation of the membrane. Upon pressurization of the top channel, membrane is deformed to confine the suspension into its negative relieves, which is then polymerized by UV irradiation, making microparticles with mold shape. The microparticles are released from the mold by relieving the pneumatic pressure and flows through the bottom channel. This one cycle of molding, polymerization, and release can be repeatedly performed in microfluidic device of which pneumatic valves are actuated in a programmed manner. The microparticles exhibit structural colors when the suspension contains high concentration of silica nanoparticles; the nanoparticles form regular arrays and the microparticles reflect specific wavelength of light as a photonic crystals. The silica nanoparticles can be selectively removed to make pronounced structural colors. In addition, the microparticles can be further functionalized by embedding magnetic particles in the matrix of the microparticles, enabling the remote control of rotational motion of microparticles.

Magnetoresponsive discoidal photonic crystals toward active color pigments.

Photonic microdisks with a multilayered structure are designed from photocurable suspensions by step-by-step photolithography. In each step of photolithography, either a colloidal photonic crystal or a magnetic-particle-laden layer is stacked over the windows of a photomask. Sequential photolithography enables the creation of multilayered photonic microdisks that have brilliant structural colors that can be switched by an external magnetic field.

Ordered packing of emulsion droplets toward the preparation of adjustable photomasks.

Monodisperse emulsion droplets with a high volume fraction form crystalline phases that can potentially serve as adjustable photomasks in photolithography. Such photomasks were prepared using a microfluidic device in which a flow-focusing junction, side channels, and a reservoir were connected in series. Transparent oil droplets were generated in a dye-containing continuous water phase at the flow-focusing junction. The droplets were then concentrated through the selective removal of the continuous phase using the side channels. This process led to the formation of a regular array of droplets in the reservoir with a configuration that depended on the relative height of the reservoir to the droplet diameter. The configurations could be selected among a single-layered hexagonal array, a bilayered square array, and a bilayered hexagonal array. The droplet arrays were used as a photomask to create hexagonal or square arrays of microdots. The transmittance profile of the ultraviolet (UV) light from each droplet was parabolic, which enabled the dot size to be tuned by controlling the UV irradiation time. This mask effect is otherwise difficult to achieve using conventional photomasks. The dot size and array periodicity could be adjusted by the in-situ control of the droplet size at the flow-focusing droplet maker. The combination of droplet size adjustments and the UV irradiation time provided independent control over the dot size and array periodicity to enable the preparation of a series of hexagonal microarrays with a wide spectrum of array parameters using a single microfluidic device.

Controlled pixelation of inverse opaline structures towards reflection-mode displays.

Pixelated inverse opals with red, green, and blue colors were prepared by hybridizing convective assembly of colloidal particles and photolithography techniques. The brilliant structural colors, high mechanical stability, and small feature size of the pixels were simultaneously accomplished, thereby providing color reflectors potentially useful for display devices. Moreover, this hybridized method provides a general means to create multi-colored photonic crystals.

3,4,5-Trihydroxycinnamic Acid Inhibits Lipopolysaccharide-Induced Inflammatory Response through the Activation of Nrf2 Pathway in BV2 Microglial Cells.

3,4,5-Trihydroxycinnamic acid (THC) is a derivative of hydroxycinnamic acids, which have been reported to possess a variety of biological properties such as anti-inflammatory, anti-tumor, and neuroprotective activities. However, biological activity of THC has not been extensively examined. Recently, we reported that THC possesses anti-inflammatory activity in LPS-stimulated BV2 microglial cells. However, its precise mechanism by which THC exerts anti-inflammatory action has not been clearly identified. Therefore, the present study was carried out to understand the anti-inflammatory mechanism of THC in BV2 microglial cells. THC effectively suppressed the LPS-induced induction of pro-inflammatory mediators such as NO, TNF-α, and IL-1ß. THC also suppressed expression of MCP-1, which plays a key role in the migration of activated microglia. To understand the underlying mechanism by which THC exerts these anti-inflammatory properties, involvement of Nrf2, which is a cytoprotective transcription factor, was examined. THC resulted in increased phosphorylation of Nrf2 with consequent expression of HO-1 in a concentration-dependent manner. THC-induced phosphorylation of Nrf2 was blocked with SB203580, a p38 MAPK inhibitor, indicating that p38 MAPK is the responsible kinase for the phosphorylation of Nrf2. Taken together, the present study for the first time demonstrates that THC exerts anti-inflammatory properties through the activation of Nrf2 in BV2 microglial cells, suggesting that THC might be a valuable therapeutic adjuvant for the treatment of inflammation-related disorders in the CNS.

Novel pyrimidines as acid pump antagonists (APAs).

A series of pyrimidine derivatives as acid pump antagonists (APAs) was synthesized and the inhibitory activities against H(+)/K(+) ATPase isolated from hog gastric mucosa were determined. After elaborating on substituents at C2 and C4 position of the pyrimidine scaffold, we have observed that the compound 7h is a potent APA with H(+)/K(+) ATPase, IC(50) = 52 nM.

A new isoflavone glycoside from the stem bark of Sophora japonica.

A new isoflavone glycoside, 6-methoxy-7-hydroxy-4'-O-beta-D-glucosyl isoflavone, glycitein-4'-O-beta-D-glucoside (10), along with nine known flavonoids, were isolated from the stem bark of Sophora japonica. The structures of these compounds were determined by analysis of spectroscopic data (1D -, 2D - NMR and HRMS). The inhibitory effects of all the isolated compounds on aldose reductase were evaluated in vitro. Among these compounds, daidzein (1), puerol A (4), and paratensein-7-O-glucoside (9) exhibited potent inhibitory effects, with IC(50) values of 3.2, 6.4, and 1.9 microM, respectively.

Novel 1H-pyrrolo[2,3-c]pyridines as acid pump antagonists (APAs).

A series of 1H-pyrrolo[2,3-c]pyridines as acid pump antagonists (APAs) was synthesized and the inhibitory activities against H(+)/K(+) ATPase isolated from hog gastric mucosa were determined. After elaborating on substituents at N1, C5, and C7 position of 1H-pyrrolo[2,3-c]pyridine scaffold, we have observed that compounds 14f and 14g are potent APAs with H(+)/K(+) ATPase IC(50)=28 and 29 nM, respectively.