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Flow Induced Motions (FIMs) of a single, rigid, circular cylinder with end-springs are investigated for Reynolds number 30,000 ≤ Re ≤ 120,000 with mass ratio, damping, and stiffness as parameters. Selective roughness is applied to enhance FIM and increase the hydrokinetic energy captured by the VIVACE (Vortex Induced Vibration for Aquatic Clean Energy) Converter at higher Reynolds numbers. The second generation of virtual spring-damping system Vck, recently developed in the Marine Renewable Energy Laboratory (MRELab), enables embedded computer-controlled change of viscous-damping and spring-stiffness for fast and precise oscillator modeling. Experimental results for amplitude response, frequency response, energy harvesting, and efficiency are presented and discussed. All experiments were conducted in the Low Turbulence Free Surface Water (LTFSW) Channel of the MRELab of the University of Michigan. The main conclusions are: (1) The oscillator can harness energy from flows as slow as 0.3946 m/s with no upper limit. (2) Increasing the spring stiffness, shifts the VIV synchronization range to higher flow velocities, resulting in reduced gap between VIV and galloping, where the harnessed power drops. (3) In galloping, the harnessed power increases with the mass ratio. (4) Local optima in energy conversion efficiency appear at the beginning of the VIV upper branch and at the beginning of galloping. (5) Local optima in power appear at the end VIV upper branch and at the beginning of galloping. [ABSTRACT FROM AUTHOR]

Ti-Ni-Ag scaffolds were prepared by sintering rapidly solidified alloy fibers. Microstructures and transformation behaviors of alloy fibers and scaffolds were investigated by means of electron probe micro-analyzer (EPMA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The B2-R-B19′ transformation occurs in alloy fibers. The alloy fibers have good superelasticity with superelastic recovery ratio of 93% after annealing heat treatment. The as-sintered Ti-Ni-Ag scaffolds possess three-dimensional and interconnected pores and have the porosity level of 80%. The heat treated Ti-Ni-Ag scaffolds not only have an elastic modulus of 0.67 GPa, which match well with that of cancellous bone, but also show excellent superelasticity at human body temperature. In terms of the mechanical properties, the Ti-Ni-Ag scaffolds in this study can meet the main requirements of bone scaffold for the purpose of bone replacement applications. [ABSTRACT FROM AUTHOR]

Horizontal hydrokinetic energy can be harnessed using Steady Lift Technology (SLT) like turbines or Alternating Lift Technology (ALT) like the VIVACE Converter. Tidal/current turbines with low mechanical losses typically achieve about 30% peak power efficiency, which is equivalent to 50.6% power efficiency over the Betz limit at flow speed nearly 3.0 m/s. The majority of flows worldwide are slower than 1.0–1.5 m/s. Turbines also require large in-flow spacing resulting in farms of low power-to-volume density. Alternating-lift overcomes these challenges. The purpose of this study is to show that the ALT Converter is a three-dimensional energy absorber that efficiently works in river/ocean currents as slow as 1.0–1.5 m/s a range of velocities presently inaccessible to watermills and turbines. This novel converter utilizes flow-induced motions (FIM), which are potentially destructive phenomena for structures, enhances them, and converts hydrokinetic energy to electricity. It was invented in the Marine Renewable Energy Lab (MRELab) and patented through the University of Michigan. MRELab has been studying the effect of passive turbulence control (PTC) to enhance FIMs and to expand their synchronization range for energy harnessing. This study shows that multiple cylinders in proximity can synergistically work and harness more energy than the same number of a single cylinder in isolation. Estimation based on experiments, shows that a 4 PTC-cylinder Converter can achieve 88.6% peak efficiency of the Betz limit at flow speed slower than 1.0 m/s and power-to-volume density of 875 W/m 3 at 1.45 m/s. Thus, the Converter can efficiently harness energy from rivers and ocean current as slow as 0.8–1.5 m/s, with no upper limit in flow velocity. [ABSTRACT FROM AUTHOR]

Background The quality of life (QOL) of patients who survive early gastric cancer (EGC) is an area of increasing interest. Objective To compare the QOL and degree of worry of cancer recurrence in EGC patients who underwent endoscopic submucosal dissection (ESD) or surgery. Design Cross-sectional study. Settings A tertiary referral center. Patients A total of 565 patients with EGC who received ESD or surgery. Intervention Questionnaires. Main Outcome Measurements QOL was evaluated using the Short-form Health Survey and the European Organization for Research and Treatment of Cancer QOL questionnaires (QLQ-C30 and EORTC-QLQ-STO22). Mood disorders and the worry of cancer recurrence were estimated using the Hospital Anxiety and Depression Scale (HADS) and Worry of Cancer Scale, respectively. Results Questionnaires were completed by 55.7% of the ESD (137/246) and 58.9% of the surgery (188/319) patients. The surgery group had more QOL-related symptomatic and functional problems, including fatigue ( P = .044), nausea/vomiting ( P = .032), appetite loss ( P = .023), diarrhea ( P < .001), pain ( P = .013), reflux symptoms ( P = .005), eating restrictions ( P < .001), anxiety ( P = .015), taste impairment ( P = .011), and poor body image ( P < .001). The ESD group had significantly higher worry of cancer recurrence scores after adjusting for covariates, especially when visiting their physicians. The HADS results did not differ between the groups. Limitations Cross-sectional design. Conclusions Endoscopic treatment for EGC provides a better QOL, but stomach preservation might provoke cancer recurrence worries. Endoscopists should address this issue for relieving a patient’s concern of cancer recurrence during follow-up period after ESD. (Clinical trial registration number: WHO ICTRP KCT0000791.) [ABSTRACT FROM AUTHOR]

Background As a result of increased resistance to antibiotics, Helicobacter pylori eradication rates using standard triple therapy have been declining. Aim To validate the efficacy and tolerability of a concomitant regimen as a first-line treatment for H. pylori infection. Methods A total of 348 naïve H. pylori -infected patients from six hospitals in Korea were randomly assigned to concomitant therapy and standard triple therapy groups. The concomitant regimen consisted of 30 mg of lansoprazole, 1 g of amoxicillin, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily for 10 days. The standard triple regimen consisted of 30 mg of lansoprazole, 1 g of amoxicillin, and 500 mg of clarithromycin, twice daily for 10 days. Results Concomitant and standard eradication rates were 78.7% (137/174) vs. 70.7% (123/174) by intention-to-treat ( p = 0.084) and 88.7% (133/150) vs. 78.4% (120/153) by per-protocol ( p = 0.016), respectively. The two groups were similar with regard to the incidence of adverse events. Conclusions Although 10-day concomitant therapy was validated as a suboptimal treatment option for the treatment of H. pylori infection, this regimen is expected to be a promising starting point in the development of an optimal treatment regimen for H. pylori infection. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose a novel approach to reconstruct the perspective-variant three-dimensional (3-D) objects along the depth direction with virtually generated elemental image arrays (V-EIAs) by ray-based pixel mapping in integral-imaging. In the proposed method, V-EIAs having different perspectives of a 3-D object are generated from the originally picked-up EIA (O-EIA) on a specific depth point by virtually moving the pinhole array back and forth along the depth direction of the 3-D object, and mapping each pixel of the O-EIA on to the corresponding positions of the V-EIAs based on ray-optics. With these V-EIAs, perspective-variant 3-D objects are finally reconstructed along the depth direction of the 3-D object. To confirm the feasibility of the proposed method, experiments with test 3-D objects are performed and the results are discussed. [Copyright &y& Elsevier]

Abstract: Aims: Although polymorphisms in IL23R have recently been proposed to predispose to Behcet''s disease (BD), associations between IL23R polymorphisms and intestinal BD have yet to be elucidated. We therefore performed a study to evaluate whether IL17A, IL23R, and STAT4 polymorphisms are associated with susceptibility to intestinal BD in the Korean population. Main methods: Single nucleotide polymorphisms (SNP) in the IL17A, IL23R, and STAT4 genes were analyzed using DNA sequencing, denaturing high performance liquid chromatography, and TaqMan genotyping assays. Key findings: Individual polymorphism analysis revealed that the TT genotype of IL17A rs8193036 (odds ratio (OR) 2.10, 95% confidence interval (CI) (1.12–3.92), p=0.021), and GG+GT genotype of IL23R rs1884444 (OR 1.92, 95% CI (1.03–3.57), p=0.034) was associated with the development of intestinal BD. When these two genotypes were combined, the risk of BD increased compared to that of patients with no-risk or one-risk genotype (OR 2.21, 95% CI (1.13–4.34), p=0.021). Furthermore, statistically significant gene–gene interactions were observed between G149R in IL23R vs. rs11685878 in STAT4, rs2275913 in IL17A vs. rs7574865 in STAT4, and rs11889341 in STAT4 vs. rs2275913 in IL17A. The haplotypes of IL17A had a positive association with intestinal BD risks, whereas those of IL23R were protective for disease development. Significance: Our results indicate that the interaction of specific IL17A, IL23R, and STAT4 SNPs modulate susceptibility to intestinal BD in the Korean population, suggesting that the IL-17/23 axis plays a significant role in disease pathogenesis. [Copyright &y& Elsevier]

Abstract: The vertical distribution of trace metals in sediment cores was investigated to evaluate the extent and the historical record of metal pollution over 30years in the artificial Lake Shihwa in Korea. A marked increase of trace metals after 1980 was observed due to the operation of two large industrial complexes and dike construction for a reclamation project. There was a decreasing trend of metal concentrations with the distance from the pollution source. The enrichment factor and pollution load index of the metals indicated that the metal pollution was mainly derived from Cu, Zn and Cd loads due to anthropogenic activities. The concentrations of Cr, Ni, Cu, Zn, As and Pb in the upper part of all core sediments exceeded the ERL criteria of NOAA. Our results indicate that inadequate planning and management of industrialization and a large reclamation project accomplished by dike construction have continued to strongly accelerate metal pollution in Lake Shihwa. [Copyright &y& Elsevier]

In order to improve image quality in single-photon emission computed tomography (SPECT)/computed tomography (CT), various studies focusing on reconstruction methods and noise reduction algorithms have been conducted. Therefore, the purpose of this study was to evaluate the efficiency of the filtered back projection (FBP) and ordered subset expectation maximization (OSEM) reconstruction methods, and to evaluate image quality after applying the median modified Wiener filter (MMWF) as a complementary noise reduction filter using 3 × 3 and 5 × 5 mask sizes. The 3D Hoffman brain phantom was used, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were evaluated in regions of interest for quantitative analysis. Based on the results, the image quality obtained by the OSEM reconstruction method was 37.7% and 25.9% higher than that of the FBP reconstruction method regarding SNR and CNR, respectively. In addition, the average SNR and CNR values obtained by applying the MMWF algorithm were 35.9% and 17.1% higher than those without the MMWF algorithm. Therefore, our results indicate that the OSEM reconstruction method is more efficient than the FBP reconstruction method, and that the MMWF algorithm improves image quality in SPECT images, regardless of which reconstruction method is used. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a novel stereoscopic video surveillance system to track a target person and detect its three-dimensional (3D) location coordinates and moving trajectory is implemented by using the pan/tilt-controlled stereo camera system. Stereoscopic video images of a target person are captured with stereo camera system and the target face and its location in the left image plane can be detected by use of YCbCr color model and centroid method. Also the target location in the right image plane can be obtained through correlation between the left face image and the right image by using the binary phase extraction joint transform correlator (BPEJTC) algorithm. With these location data of the target face in the left and right image planes the pan/tilt systems can control the stereo camera to track a target person by positioning the target face at the center of the camera’s FOV and making the focusing points of the right and left camera coincided on the target face. And then, with the resultant pan/tilt angles and geometric parameters of the stereo camera system, the target’s real 3D location coordinates and moving trajectory in the world space can be obtained. From some experiments with 900 frames of stereoscopic video image pairs, it is analyzed that the target’s center location after being tracked is kept to be very low error ratio of 0.62%, 2.04% on the average in the x, y directions of the image plane, respectively. Also, the error ratio between the calculated and measured values of the 3D location coordinates of a target person is found to be very low value of 2.1%, 5.7% on the average in the X and Y directions of the real world space, respectively. [Copyright &y& Elsevier]

Abstract: In this paper, a novel configuration of LCD projectors for efficiently polarized stereoscopic projection with improved light efficiency is presented. In the proposed scheme, polarization orientations of the analyzers in the LCD engine of one projector are rotated by 90° with respect to those of the other one, so it causes to rotate orientations of polarized outputs by 90° as well as to change operational modes of LCD panels from the normally black mode to the normally white mode or vice versa. Then, by exchanging the green color components between the modified and original LCD projectors, two orthogonally polarized views for stereoscopic projection could be obtained without use of external polarizers. Analysis on the operational mode conversions of the LCD engines with rotation of the analyzers is discussed and its experimental results are provided. [Copyright &y& Elsevier]

Abstract: In order to investigate spatial and temporal distribution of organic pollutants in the Saemangeum Bay, organophosphorus pesticides (10), alkylphenols (8), chlorophenols (2), bisphenol A were analyzed from the surface seawater taken in 2002–2003. Most of the analytes were not detected in all stations except nonylphenol and S-benzyl-O,O-di-isopropyl phosphorothioate (IBP). Concentrations of nonylphenol and IBP ranged from ND to 298 ng/l and from ND to 1840 ng/l, respectively. The high levels of nonylphenol and IBP were found in the estuary areas of Mangyeong and Dongjin River. The levels of nonylphenol and IBP in surface seawater varied through seasons and the high levels of nonylphenol and IBP were in summer season (August). Based on real time monitoring of IBP and on correlation between concentrations of target compounds and contents of salinity in seawater, physical mixing and diffusion of seawater were found to be the major factors that affect the spatial distribution of IBP and nonylphenol in the Saemangeum Bay environment. [Copyright &y& Elsevier]

Abstract: In this paper, a new liquid crystal display (LCD)-based polarized stereoscopic projection method with improved light efficiency is suggested. In the proposed system, two external polarizers are taken away from the conventional LCD polarized stereoscopic projection system by effectively taking into account of inherent polarization properties of the LCD projectors, so that light efficiency of the proposed system can be dramatically improved. From some experimental results with the Type-1 LCD projectors of NEC MT 1060R, it is found that the proposed system shows minimum light loss in the polarization process and the resultant stereoscopic image projected from this system is 213%, 75% and 300% brighter than those projected from the conventional Type-1 LCD projector-based, Type-2 LCD projector-based and Type-3 projector-based systems, respectively. [Copyright &y& Elsevier]

The disc cell wall facing the secretory cavity in lipophilic glands of Cannabis was studied for origin and distribution of hyaline areas, secretory vesicles, fibrillar matrix and particulate material. Secretions evident as light areas in the disc cell cytoplasm pass through modified regions in the plasma membrane and appear as hyaline areas ill the cell wall. Hyaline areas, surrounded with a filamentous outline, accumulate near tile wall surface lacing the secretory cavity where they fuse to form enlarged hyaline areas. Fibrillar matrix is related to and may originate from the dense outer layer of the plasma membrane. This matrix becomes distributed throughout the wall material and contributes in part to tile composition of the surface feature of secretory vesicles. Thickening of the cell wall is associated with secretions from the disc cells that facilitates movement of hyaline areas, fibrillar matrix and other possible secretions through the wall to form secretory vesicles anti intervesicular materials in the secretory cavity. The outer wall of disc ceils in aggregate forms the basilar wall surface of the secretory cavity which facilitates the organization of secretory vesicles that fill the secretory cavity. [ABSTRACT FROM AUTHOR]

Early development of the secretory cavity of chemically fixed peltate glands in Humulus lupulus L. showed secretions with different densities, light, gray and dark, in the cytoplasm of disc cells and in the periplasmic space adjacent to the developing secretory cavity. Secretions were detected in the disc cell wall and subsequently in the developing secretory cavity under the subcuticular wall of the sheath. Light and gray secretions in the cavity possessed a membrane-like surface feature. Secretions were in contact with the irregular inner surface of the cuticle. Secretions contributed to the thickening of the cuticle, whereas the membrane-like surface feature contributed to a network of Cannabis striae distributed throughout the cuticle. This study supports an early development and organization of the secretory cavity in H. lupulus, parallel to those in Cannabis, and may represent common features for lipophilic glands in angiosperms. [ABSTRACT FROM AUTHOR]

The Vortex-Induced Vibration for Aquatic Clean Energy converter is an alternating lift technology converter (ALT) utilizing flow-induced oscillations (FIOs) to harness power from currents/tides/rivers. This paper reviews the underlying concepts and all research breakthroughs made in the ALT over the last ten years by the Marine Renewable Energy Laboratory. Various scale-prototypes and virtual damper-spring systems have been developed to investigate FIOs systematically and, thus, find ways to enhance them for harnessing hydrokinetic energy more efficiently. Applying passive-turbulence control and utilizing the synergy of multiple cylinders, the ALT is able to work over a broad range of flow speeds and extract more hydrokinetic energy. The efficiency of laboratory-prototypes and large-scale prototypes tested in a river reached 52% and 20%, respectively. Furthermore, several field-tests show that the ALT is environmentally friendly and financially competitive based on the estimation of the levelized cost of energy. • An alternating-lift converter was tested in the MRELab and St. Clair River for 10yrs. • Converter uses passive turbulence control and synergistic flow-induced oscillations. • The power efficiency of the ALT converter reaches 88% of the Betz limit. • Adaptive harnessing damping increases single-cylinder power output by 25%. • The ALT presents a viable Current Energy Converter technology that is environmentally compatible. [ABSTRACT FROM AUTHOR]

The effect of pregnancy on inflammatory bowel disease (IBD) remains poorly understood. We aimed to monitor intestinal inflammation using fecal calprotectin (FC) in pregnant women and their babies during early life. Pregnant women with or without IBD and their infants were prospectively enrolled. FC levels were measured at each trimester of pregnancy and in babies throughout the first 3 years of life. Repeated-measures analysis was applied to investigate changes in FC levels while adjusting for confounders. The FC levels were correlated with the bacterial abundance in both mothers and babies. Six hundred and fourteen fecal samples from 358 mothers (98 with IBD) and 1005 fecal samples from 289 infants (76 born to IBD mothers) were analyzed. Pregnant Patients with IBD maintained higher FC levels through pregnancy compared with controls (P = 7.5 × 10–54). FC gradually increased in controls and declined in Patients with IBD throughout pregnancy (P for interaction = 5.8 × 10–7). Babies born to mothers with IBD presented with significantly higher FC levels than those born to controls up to 3 years of age, after adjusting for sex, delivery mode, feeding behavior, and antibiotics exposure (2 weeks to 3 months of age, P =.015; 12–36 months of age, P =.00003). Subdoligranulum, Roseburia, Fusicatenibacter , and Alistipes negatively correlated, and Streptococcus , Prevotella , Escherichia-Shigella , and Bifidobacterium positively correlated with maternal FC levels at T3. Faecalibacterium, Bifidobacterium , and Alistipes showed negative correlations, and Streptococcus were positively correlated with FC levels within 3 months of birth. Pregnancy is associated with decreased inflammatory activity in mothers with IBD. Higher FC levels in babies born to mothers with IBD suggest subclinical inflammation in early life, the long-term consequences of which are uncertain. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study evaluated the possible role of interleukin (IL)-10 promoter polymorphisms in children with atopic dermatitis (AD). IL-10 promoter polymorphisms are associated with the phenotype of AD in children. [Copyright &y& Elsevier]