1,149 research outputs found
Round Cell Variant of Myxoid Liposarcoma in a Japanese Macaque (Macaca fuscata)
A 5-year-old, female, Japanese Macaque (Macaca fuscata) was diagnosed with round cell variant of myxoid liposarcoma. At necropsy, multifocal to coalescing, reddish tan to white nodules, ranging from 0.5 to 1 cm in diameter, were noted throughout the omentum and retroperitoneum. Similar neoplastic nodules were also present in diaphragm, abdominal wall, and on hepatic capsule. Microscopically, neoplastic masses consisted of round to polyhedral cells, which had round, often eccentric nuclei and abundant eosinophilic granular and microvacuolated cytoplasm; Oil red O staining demonstrated large numbers of lipid droplets in the cytoplasm. Ultrastructurally, the cytoplasm of the tumor cells was packed with occasional lipid vacuoles and numerous enlarged mitochondria. Immunohistochemistry revealed tumor cells were positive for vimentin, while negative to cytokeratin, actin, and Factor VIII–related antigen. To the authors' knowledge, this is the first report of round-cell variant of myxoid liposarcoma in nonhuman primate.This study was supported through Brain Korea 21
Program for Veterinary Science
Control of Crystallographic Orientation in Ferroelectric Bi 3.15 La 0.85 Ti 3 O 12 Thin Films by Rapid Thermal Annealing
Ferroelectric Bi 3.15 La 0.85 Ti 3 O 12 ͑BLT͒ thin films were fabricated on SiO 2 /Si 3 N 4 /SiO 2 substrates by a sol-gel spin coating method. The orientations of the BLT thin films were controlled by an intermediate rapid thermal annealing ͑RTA͒ process. The BLT thin films prepared using the RTA process at Ͻ400°C showed the ͑117͒ preferred orientation, while films preannealed at у450°C showed a stronger ͑006͒ peak than a ͑117͒ peak. A nearly perfect c axis orientation was obtained by RTA at Ͼ500°C and a subsequent furnace annealing at 700°C. It was found that 400 Å thin BLT films with one layer coating were partially crystallized at even for a rapid thermal process temperature lower than 500°C. Transmission electron microscopy analysis indicated that c axis oriented nuclei were formed at 500°C RTA and these nuclei function as seeds in the growth of BLT films with an almost perfect c axis orientation during the final furnace annealing stage. The surface morphology of c axis oriented BLT thin films showed smooth and plate-like grains while rod-like shapes were observed in the ͑117͒ oriented films. Ferroelectric random access memory ͑FeRAM͒ with metal/ ferroelectric/semiconductor field-effect transistor ͑MFSFET͒ structures have the advantages of saving electrical power and decreasing memory cell size and this type of memory utilizes the remanent polarization of a ferroelectric thin film to control the surface potential of a silicon substrate. MFSFETs may be operated in the form of a nondestructive readout ͑NDRO͒ scheme. However, this structure has not yet been demonstrated due to difficulties in forming reliable ferroelectric thin films directly on a silicon surface. Elements in the film may diffuse into silicon, 1 forming an uncontrollable oxide layer, thus degrading the interface characteristics. To solve these problems, a metal/ferroelectric/insulator/semiconductor field-effect transistor ͑MFISFET͒ structure has been proposed and has been studied extensively. The most commonly used insulators ͑interdielectric layers͒ for the study are silicon nitride, Y 2 O 3 , CeO 2 , and ZrO 2 . 2-6 Recently lanthanum-substituted bismuth titanate ͑BLT͒ thin films have attracted considerable attraction for use in switching polarization parts in MFIS structures due to their low process temperature and good ferroelectric properties. 9 Therefore, the crystallographic orientations of BLT thin films have been of great concern in terms of controlling the polarization characteristics for each application. BLT thin films are strongly dependent on crystallographic orientation in terms of process conditions and substrate materials. Recent reports have pointed out the importance of annealing conditions. Kijima et al. reported that BLT tends to have a (00l) preferred orientation if it is preannealed below 400°C and a random orientation if preannealed Ͼ500°C in Pt/BLT/Si 3 N 4 /Si structure. 10 Yang et al. reported that random oriented BLT films could be obtained by rapid thermal annealing ͑RTA͒ at 500°C, but c axis oriented films were formed at a higher temperature, 600°C, in Pt/BLT/Pt. 11 However, a clear explanation for the dependency of crystallographic orientation in BLT thin films is not available. In this report, we demonstrate the orientational conversion of BLT films in relation to the intermediate rapid thermal annealing process and the microstructural properties of c axis oriented BLT films are also investigated. After deposition, the films were placed on a hot plate ͑at ϳ200°C͒ in air for 5 min to remove solvents and other organic materials. The resulting films were then preannealed by RTA at 400-550°C for 1 min. These steps were repeated and the final film thickness was set at 120 nm with a three-layer coating. Postdeposition annealing of the films was carried out in a furnace from 650 to 800°C for 30 min under an oxygen environment. The surface morphologies and roughness were determined by scanning electron microscopy ͑SEM, Akashi DS-130C͒ and atomic force microscopy ͑AFM͒. The crystal structures were examined by high-resolution transmission electron microscopy ͑HRTEM, Philips, CM20T/STEM͒. The diffraction patterns were recorded on a Regaku X-ray diffractometer using Cu K␣ radiation ͑30 keV͒ at a scanning speed of 2°͑2͒/min. To investigate the cause of orientation change by different RTA * Electrochemical Society Active Member.
Directed self-assembly of a helical nanofilament liquid crystal phase for use as structural color reflectors
The fabrication of molecular structures with a desired morphology, e.g., nanotubes, nanoribbons, nanosprings, and sponges, is essential for the advancement of nanotechnology. Unfortunately, realization of this objective is expensive and complicated. Here, we report that irradiating a film comprising azobenzene derivatives with UV light produces oriented arrays of helical nanofilaments via the photoisomerization-induced Weigert effect. As a result, structural colors are observed due to the extrinsic chiral reflection in the visible wavelength range, and the reflected color can be tuned by adjusting the molecular length of the azobenzene derivative. This simple fabrication method can be used for fabricating large, reversible, and patternable color reflectors, providing a new platform for interference-based structural coloration as it exists in nature, such as morpho butterflies, green-winged teal, and various beetles
Oncogenic CagA Promotes Gastric Cancer Risk via Activating ERK Signaling Pathways: A Nested Case-Control Study
Background: CagA cellular interaction via activation of the ERK signaling pathway may be a starting point in the development of gastric cancer. This study aimed to evaluate whether genes involved in ERK downstream signaling pathways activated by CagA are susceptible genetic markers for gastric cancer. Methods: In the discovery phase, a total of 580 SNPs within +/-5 kbp of 30 candidate genes were genotyped to examine an association with gastric cancer risk in the Korean Multi-center Cancer Cohort (100 incident gastric cancer case-control sets). The most significant SNPs (raw or permutated p value??0.02) identified in the discovery analysis were re-evaluated in the extension phase using unconditional logistic regression model (400 gastric cancer case-control sets). Combined analyses including pooled-and meta-analysis were conducted to summarize all the results. Results: 24 SNPs in eight genes (ERK, Dock180, C3G, Rap1, Src, CrkL, Mek and Crk) were significantly associated with gastric cancer risk in the individual SNP analyses in the discovery phase (p??0.05). In the extension analyses, ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 showed marginally significant gene-dose effects for gastric cancer. Consistently, final combined analysis presented the SNPs as significantly associated with gastric cancer risk (OR = 1.56, [95% CI: 1.19-2.06], OR = 0.61, [95% CI: 0.43-0.87], OR = 0.59, [95% CI: 0.54-0.76], respectively). Conclusions: Our findings suggest that ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 are genetic determinants in gastric carcinogenesis
Gene Flow between the Korean Peninsula and Its Neighboring Countries
SNP markers provide the primary data for population structure analysis. In this study, we employed whole-genome autosomal SNPs as a marker set (54,836 SNP markers) and tested their possible effects on genetic ancestry using 320 subjects covering 24 regional groups including Northern ( = 16) and Southern ( = 3) Asians, Amerindians ( = 1), and four HapMap populations (YRI, CEU, JPT, and CHB). Additionally, we evaluated the effectiveness and robustness of 50K autosomal SNPs with various clustering methods, along with their dependencies on recombination hotspots (RH), linkage disequilibrium (LD), missing calls and regional specific markers. The RH- and LD-free multi-dimensional scaling (MDS) method showed a broad picture of human migration from Africa to North-East Asia on our genome map, supporting results from previous haploid DNA studies. Of the Asian groups, the East Asian group showed greater differentiation than the Northern and Southern Asian groups with respect to Fst statistics. By extension, the analysis of monomorphic markers implied that nine out of ten historical regions in South Korea, and Tokyo in Japan, showed signs of genetic drift caused by the later settlement of East Asia (South Korea, Japan and China), while Gyeongju in South East Korea showed signs of the earliest settlement in East Asia. In the genome map, the gene flow to the Korean Peninsula from its neighboring countries indicated that some genetic signals from Northern populations such as the Siberians and Mongolians still remain in the South East and West regions, while few signals remain from the early Southern lineages
EGb761, a Ginkgo Biloba Extract, Is Effective Against Atherosclerosis In Vitro, and in a Rat Model of Type 2 Diabetes
BACKGROUND: EGb761, a standardized Ginkgo biloba extract, has antioxidant and antiplatelet aggregation and thus might protect against atherosclerosis. However, molecular and functional properties of EGb761 and its major subcomponents have not been well characterized. We investigated the effect of EGb761 and its major subcomponents (bilobalide, kaemferol, and quercetin) on preventing atherosclerosis in vitro, and in a rat model of type 2 diabetes. METHODS AND RESULTS: EGb761 (100 and 200 mg/kg) or normal saline (control) were administered to Otsuka Long-Evans Tokushima Fatty rats, an obese insulin-resistant rat model, for 6 weeks (from 3 weeks before to 3 weeks after carotid artery injury). Immunohistochemical staining was performed to investigate cell proliferation and apoptosis in the injured arteries. Cell migration, caspase-3 activity and DNA fragmentation, monocyte adhesion, and ICAM-1/VCAM-1 levels were explored in vitro. Treatment with EGb761 dose-dependently reduced intima-media ratio, proliferation of vascular smooth muscle cells (VSMCs) and induced greater apoptosis than the controls. Proliferation and migration of VSMCs in vitro were also decreased by the treatment of EGb761. Glucose homeostasis and circulating adiponectin levels were improved, and plasma hsCRP concentrations were decreased in the treatment groups. Caspase-3 activity and DNA fragmentation increased while monocyte adhesion and ICAM-1/VCAM-1 levels decreased significantly. Among subcomponents of EGb761, kaemferol and quercetin reduced VSMC migration and increased caspase activity. CONCLUSIONS: EGb761 has a protective role in the development of atherosclerosis and is a potential therapeutic agent for preventing atherosclerosis
Measurements of the properties of Lambda_c(2595), Lambda_c(2625), Sigma_c(2455), and Sigma_c(2520) baryons
We report measurements of the resonance properties of Lambda_c(2595)+ and
Lambda_c(2625)+ baryons in their decays to Lambda_c+ pi+ pi- as well as
Sigma_c(2455)++,0 and Sigma_c(2520)++,0 baryons in their decays to Lambda_c+
pi+/- final states. These measurements are performed using data corresponding
to 5.2/fb of integrated luminosity from ppbar collisions at sqrt(s) = 1.96 TeV,
collected with the CDF II detector at the Fermilab Tevatron. Exploiting the
largest available charmed baryon sample, we measure masses and decay widths
with uncertainties comparable to the world averages for Sigma_c states, and
significantly smaller uncertainties than the world averages for excited
Lambda_c+ states.Comment: added one reference and one table, changed order of figures, 17
pages, 15 figure
Status and Prospects of ZnO-Based Resistive Switching Memory Devices
In the advancement of the semiconductor device technology, ZnO could be a prospective alternative than the other metal oxides for its versatility and huge applications in different aspects. In this review, a thorough overview on ZnO for the application of resistive switching memory (RRAM) devices has been conducted. Various efforts that have been made to investigate and modulate the switching characteristics of ZnO-based switching memory devices are discussed. The use of ZnO layer in different structure, the different types of filament formation, and the different types of switching including complementary switching are reported. By considering the huge interest of transparent devices, this review gives the concrete overview of the present status and prospects of transparent RRAM devices based on ZnO. ZnO-based RRAM can be used for flexible memory devices, which is also covered here. Another challenge in ZnO-based RRAM is that the realization of ultra-thin and low power devices. Nevertheless, ZnO not only offers decent memory properties but also has a unique potential to be used as multifunctional nonvolatile memory devices. The impact of electrode materials, metal doping, stack structures, transparency, and flexibility on resistive switching properties and switching parameters of ZnO-based resistive switching memory devices are briefly compared. This review also covers the different nanostructured-based emerging resistive switching memory devices for low power scalable devices. It may give a valuable insight on developing ZnO-based RRAM and also should encourage researchers to overcome the challenges
Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay
We reconstruct the rare decays , , and in a data sample
corresponding to collected in collisions at
by the CDF II detector at the Fermilab Tevatron
Collider. Using and decays we report the branching ratios. In addition, we report
the measurement of the differential branching ratio and the muon
forward-backward asymmetry in the and decay modes, and the
longitudinal polarization in the decay mode with respect to the squared
dimuon mass. These are consistent with the theoretical prediction from the
standard model, and most recent determinations from other experiments and of
comparable accuracy. We also report the first observation of the {\mathcal{B}}(B^0_s \to
\phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}27 \pm 6B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let
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