Contact holes in vertical electrode structures analyzed by voltage contrast-SEM and conducting AFM

Soaring demands of multi-stacked memory devices request urgent development of backside contact electrode technologies, such as high aspect ratio etching, metallization, and inspection methods. Especially the complex metal contact process should be monitored for each manufacturing step to filter the defective samples and to maintain the high yield of production. Among the inspection methods for detecting the electrical connections, there is voltage contrast (VC)-SEM and conducting AFM (C-AFM). In this report, we investigated the two inspection methods for testing designed samples with different contact hole states. The VC-SEM data shows the contrast variation at the contact holes, from which one may discern the contact status with an optimum voltage. The C-AFM results clearly demonstrate a finite electrical current in the connected contact, while a negligible current in the disconnected one. Finally, we discuss insights of using the two methods for analyzing the contact hole technologies with high aspect ratios.Comment: 17 pages, 4 figure

Tetramethyl-O-scutellarin isolated from peels of immature Shiranuhi fruit exhibits anti-inflammatory effects on LPSinduced RAW264.7 cells

Purpose: To investigate the anti-inflammatory activity of the ethanol extract of the immature fruit of a citrus, Shiranuhi, and to identify the active ingredient.Methods: The immature Shiranuhi peel was extracted with 80 % ethanol, and the extract was fractionated with solvents (n-hexane, ethyl acetate and n-butanol) to afford the corresponding fractions and water residue. Among them, the EtOAc-soluble portion was subjected to medium pressure liquid chromatography (MPLC) over a reversed-phase SiO2 column to give compound 1. The isolated compound was identified based on the proton and carbon nuclear magnetic resonance (NMR) spectra. The release of nitric oxide, prostaglandin (PG)E2, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 secreted by mouse macrophages was measured using RAW264.7 cell culture supernatant.Results: Shiranuhi (Korean name, Hallabong) is an important citrus species cultivated in Jeju Island, Korea. A polymethoxyflavonoid (PMF), tetramethyl-O-scutellarin (1), was isolated from the peels of immature Shiranuhi fruit. Upon the evaluation of anti-inflammatory effects, the flavonoid 1 decreased the nitric oxide production in macrophage cells with high efficiency, viz, 50 % inhibition concentration, IC50 of 57.4 μM. Subsequent studies demonstrated that PMF 1 effectively inhibited the generation of PGE2, TNF-α, IL-1β, and IL-6 cytokine in a dose-dependent manner.Conclusion: Tetramethyl-O-scutellarin (1) has been successfully isolated from Shiranuhi species for the first time. Thus, Shiranuhi fruit peel extract containing PMF 1 can potentially be applied as an antiinflammatory ingredient in food or cosmetic industries.Keywords: Shiranuhi fruit, Nitric oxide, Tetramethyl-O-scutellarin, Anti-inflammator

Microlensing under Shear

We investigate the distortions due to this shear in the microlensing light curves and in the astrometric microlensing centroid shift trajectories. As expected, the light curve deviation increases as the shear increases and the impact parameter decreases. Although the light curve in the presence of a small shear is similar to the simple Paczynski curve with a slightly smaller impact parameter, the detailed difference between the light curve with and without shear reflects the direction and the magnitude of the shear. The centroid shift trajectory also deviates from a simple ellipse in the presence of shear. The distortion of the centroid shift trajectory increases as the impact parameter decreases, and the shape of the trajectory becomes complicated when the impact parameter becomes small enough. The magnitude of the maximum distortion depends on the magnitude and the direction of the shear. For a source trajectory in a given direction, the time of the maximum distortion depends mostly on the impact parameter and hardly on the shear. It is possible to determine the magnitude of the shear and its direction if both the time and the magnitude of the maximum astrometric distortion are measured. The magnitude of the shear produced by the Galactic bulge or a globular cluster falls in the range 10^{-6}--10^{-4} in normalized units. Although the actual determination of the shear from the Galactic sub-structures will not be easy due to complications such as binary companion, future large scale microlensing experiments may enable us to determine the shear in some high amplification events, leading eventually to mapping the Galactic mass distribution.Comment: 15 pages, 11 figures, ApJ accepe

Acanthopanax koreanum Fruit Waste Inhibits Lipopolysaccharide-Induced Production of Nitric Oxide and Prostaglandin E2 in RAW 264.7 Macrophages

The Acanthopanax koreanum fruit is a popular fruit in Jeju Island, but the byproducts of the alcoholic beverage prepared using this fruit are major agricultural wastes. The fermentability of this waste causes many economic and environmental problems. Therefore, we investigated the suitability of using A. koreanum fruit waste (AFW) as a source of antiinflammatory agents. AFWs were extracted with 80% EtOH. The ethanolic extract was then successively partitioned with hexane, CH2Cl2, EtOAc, BuOH, and water. The results indicate that the CH2Cl2 fraction (100 μg/mL) of AFW inhibited the LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production in RAW 264.7 cells by 79.6% and 39.7%, respectively. These inhibitory effects of the CH2Cl2 fraction of AFWs were accompanied by decreases in the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and iNOS and COX-2 mRNA in a dose-dependent pattern. The CH2Cl2 fraction of AFWs also prevented degradation of IκB-α in a dose-dependent manner. Ursolic acid was identified as major compound present in AFW, and CH2Cl2 extracts by high performance liquid chromatography (HPLC). Furthermore using pure ursolic acid as standard and by HPLC, AFW and CH2Cl2 extracts was found to contain 1.58 mg/g and 1.75 mg/g, respectively. Moreover, we tested the potential application of AFW extracts as a cosmetic material by performing human skin primary irritation tests. In these tests, AFW extracts did not induce any adverse reactions. Based on these results, we suggest that AFW extracts be considered possible anti-inflammatory candidates for topical application

The cortical activation pattern by a rehabilitation robotic hand: a functional NIRS study

Introduction: Clarification of the relationship between external stimuli and brain response has been an important topic in neuroscience and brain rehabilitation. In the current study, using functional near infrared spectroscopy (fNIRS), we attempted to investigate cortical activation patterns generated during execution of a rehabilitation robotic hand. Methods: Ten normal subjects were recruited for this study. Passive movements of the right fingers were performed using a rehabilitation robotic hand at a frequency of 0.5 Hz. We measured values of oxy-hemoglobin (HbO), deoxy-hemoglobin (HbR) and total-hemoglobin (HbT) in five regions of interest: the primary sensory-motor cortex (SM1), hand somatotopy of the contralateral SM1, supplementary motor area (SMA), premotor cortex (PMC), and prefrontal cortex (PFC). Results: HbO and HbT values indicated significant activation in the left SM1, left SMA, left PMC, and left PFC during execution of the rehabilitation robotic hand (uncorrected, p < 0.01). By contrast, HbR value indicated significant activation only in the hand somatotopic area of the left SM1 (uncorrected, p < 0.01). Conclusions: Our results appear to indicate that execution of the rehabilitation robotic hand could induce cortical activation. © 2014 Chang, Lee, Gu, Lee, Jin, Yeo, Seo and Jang.1

Does the Kyphotic Change Decrease the Risk of Fall?

ObjectivesFalls are a major problem in the elderly. Age-related degeneration of the human balance system increases the risk of falls. Kyphosis is a common condition of curvature of the upper spine in the elderly and its development occurs through degenerative change. However, relatively little is known about the effect of kyphotic changes on balance in the elderly. The aim of this study is to investigate the influence of kyphosis on the balance strategy through use of the motor control test (MCT) in computerized dynamic posturography.MethodsFifty healthy subjects who were not affected by other medical disorders that could affect gait or balance were enrolled in the study. By simulation of kyphotic condition through change of the angles of the line connecting the shoulder to the hip and the ankle axis by approximately 30°, the latency and amplitude of the MCT were measured in upright and kyphotic condition.ResultsIn the kyphotic condition, latency was shortened in backward movement. In forward movement, latency was shortened only in large stimulation. The amplitude in forward movement was decreased in kyphotic condition. However, the change of amplitude was not significant in large intensity backward movement in the same condition.ConclusionKyphotic condition decreases the latency of MCT, especially in backward movement. These findings imply that kyphotic condition may serve as a protective factor against falls

Electrical spin injection and detection in an InAs quantum well

We demonstrate fully electrical detection of spin injection in InAs quantum wells. A spin polarized current is injected from a NiFe thin film to a two-dimensional electron gas (2DEG) made of InAs based epitaxial multi-layers. Injected spins accumulate and diffuse out in the 2DEG, and the spins are electrically detected by a neighboring NiFe electrode. The observed spin diffusion length is 1.8 um at 20 K. The injected spin polarization across the NiFe/InAs interface is 1.9% at 20 K and remains at 1.4% even at room temperature. Our experimental results will contribute significantly to the realization of a practical spin field effect transistor

Microlensing Optical Depth Revisited with Recent Star Counts

More reliable constraints on the microlensing optical depth comes from a better understanding of the Galactic model. Based on well-constrained Galactic bulge and disk models constructed from survey observations, such as, HST, 2MASS, and SDSS, we calculate the microlensing optical depths toward the Galactic bulge fields, and compare them with recent results of microlensing surveys. We test chi^2 statistics of microlensing optical depths expected from those models, as well as previously proposed models, using two types of data: optical depth map in (l, b) and averaged optical depth over the Galactic longitude l as a function of the latitude b. From this analysis, we find that the Galactic bulge models of 2MASS, Han & Gould (2003), and G2 of Stanek et al. (1997) show a good agreement with the microlensing optical depth profiles for all the microlensing observations, compared with E2 of Stanek et al. (1997). We find, on the other hand, that models involving an SDSS disk model produce relatively higher chi^2 values. It should be noted that modeled microlensing optical depths diverge in the low Galactic latitude, |b| < 2 arcdeg. Therefore, we suggest the microlensing observation toward much closer to central regions of the Galaxy to further test the proposed Galactic models, if it is more technically feasible than waiting for large data set of microlensing events.Comment: 15 pages, 3 figures and 3 tables, accepted for publication in Ap

Sargachromenol from Sargassum micracanthum

During our ongoing screening program designed to determine the anti-inflammatory potential of natural compounds, we isolated sargachromenol from Sargassum micracanthum. In the present study, we investigated the anti-inflammatory effects of sargachromenol on lipopolysaccharide (LPS)-induced inflammation in murine RAW 264.7 macrophage cells and the underlying mechanisms. Sargachromenol significantly inhibited the LPS-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2) in a dose-dependent manner. It also significantly inhibited the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner in LPS-stimulated macrophage cells. Further analyses showed that sargachromenol decreased the cytoplasmic loss of inhibitor κBα (IκBα) protein. These results suggest that sargachromenol may exert its anti-inflammatory effects on LPS-stimulated macrophage cells by inhibiting the activation of the NF-κB signaling pathway. In conclusion, to our knowledge, this is the first study to show that sargachromenol isolated from S. micracanthum has an effective anti-inflammatory activity. Therefore, sargachromenol might be useful for cosmetic, food, or medical applications requiring anti-inflammatory properties

Hysteroscopic Resection of the Vaginal Septum in Uterus Didelphys with Obstructed Hemivagina: A Case Report

Uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis is a rare congenital anomaly. Excision of the obstructed vaginal septum is the treatment of choice for symptom relief and the preservation of reproductive capability. A 14-yr-old girl complained of persistent vaginal spotting following each menstruation. Pelvic magnetic resonance imaging revealed a uterus didelphys with left hematocolpos and ipsilateral renal agenesis. Instead of conventional transvaginal excision of the vaginal septum, we used hysteroscopic excision under transabdominal ultrasonographic guidance to preserve the integrity of the hymen. The postoperative course was uneventful, and clinical symptoms were completely resolved after this intervention. Resectoscopic excision of the vaginal septum was found to be easy, safe, effective, and appropriate for young women as it preserved hymen integrity. We believe that this is the first Korean report on the use of a hysteroscopy for vaginal septum resection in a patient with uterus didelphys with obstructed hemivagina