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Showing papers by "Sungkyunkwan University published in 2011"


Journal ArticleDOI
TL;DR: Perovskite QD-sensitized 3.6 μm-thick TiO(2) film shows maximum external quantum efficiency (EQE) of 78.6% at 530 nm and solar-to-electrical conversion efficiency of 6.54% at AM 1.5G 1 sun intensity (100 mW cm(-2)), which is by far the highest efficiency among the reported inorganic quantum dot sensitizers.
Abstract: Highly efficient quantum-dot-sensitized solar cell is fabricated using ca. 2–3 nm sized perovskite (CH3NH3)PbI3 nanocrystal. Spin-coating of the equimolar mixture of CH3NH3I and PbI2 in γ-butyrolactone solution (perovskite precursor solution) leads to (CH3NH3)PbI3 quantum dots (QDs) on nanocrystalline TiO2 surface. By electrochemical junction with iodide/iodine based redox electrolyte, perovskite QD-sensitized 3.6 μm-thick TiO2 film shows maximum external quantum efficiency (EQE) of 78.6% at 530 nm and solar-to-electrical conversion efficiency of 6.54% at AM 1.5G 1 sun intensity (100 mW cm−2), which is by far the highest efficiency among the reported inorganic quantum dot sensitizers.

2,781 citations


Journal ArticleDOI
27 May 2011-Science
TL;DR: The differences across cultures in the enforcement of conformity may reflect their specific histories and advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change.
Abstract: With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change.

1,895 citations


Journal ArticleDOI
TL;DR: The Avastin in Gastric Cancer (AVAGAST) trial as discussed by the authors evaluated the efficacy of adding bevacizumab to capecitabine-cisplatin in the first-line treatment of advanced gastric cancer.
Abstract: Purpose The Avastin in Gastric Cancer (AVAGAST) trial was a multinational, randomized, placebo-controlled trial designed to evaluate the efficacy of adding bevacizumab to capecitabine-cisplatin in the first-line treatment of advanced gastric cancer. Patients and Methods Patients received bevacizumab 7.5 mg/kg or placebo followed by cisplatin 80 mg/m2 on day 1 plus capecitabine 1,000 mg/m2 twice daily for 14 days every 3 weeks. Fluorouracil was permitted in patients unable to take oral medications. Cisplatin was given for six cycles; capecitabine and bevacizumab were administered until disease progression or unacceptable toxicity. The primary end point was overall survival (OS). Log-rank test was used to test the OS difference. Results In all, 774 patients were enrolled; 387 were assigned to each treatment group (intention-to-treat population), and 517 deaths were observed. Median OS was 12.1 months with bevacizumab plus fluoropyrimidine-cisplatin and 10.1 months with placebo plus fluoropyrimidine-cisplati...

943 citations


Journal ArticleDOI
28 Jan 2011-Science
TL;DR: How genomic plasticity within lineages of recombinogenic bacteria can permit adaptation to clinical interventions over remarkably short time scales is detailed.
Abstract: Epidemiological studies of the naturally transformable bacterial pathogen Streptococcus pneumoniae have previously been confounded by high rates of recombination. Sequencing 240 isolates of the PMEN1 (Spain23F-1) multidrug-resistant lineage enabled base substitutions to be distinguished from polymorphisms arising through horizontal sequence transfer. More than 700 recombinations were detected, with genes encoding major antigens frequently affected. Among these were 10 capsule-switching events, one of which accompanied a population shift as vaccine-escape serotype 19A isolates emerged in the USA after the introduction of the conjugate polysaccharide vaccine. The evolution of resistance to fluoroquinolones, rifampicin, and macrolides was observed to occur on multiple occasions. This study details how genomic plasticity within lineages of recombinogenic bacteria can permit adaptation to clinical interventions over remarkably short time scales.

870 citations


Journal ArticleDOI
11 May 2011-ACS Nano
TL;DR: It is shown that graphene provides a promising biocompatible scaffold that does not hamper the proliferation of human mesenchymal stem cells and accelerates their specific differentiation into bone cells, demonstrating graphene's potential for stem cell research.
Abstract: Current tissue engineering approaches combine different scaffold materials with living cells to provide biological substitutes that can repair and eventually improve tissue functions. Both natural and synthetic materials have been fabricated for transplantation of stem cells and their specific differentiation into muscles, bones, and cartilages. One of the key objectives for bone regeneration therapy to be successful is to direct stem cells’ proliferation and to accelerate their differentiation in a controlled manner through the use of growth factors and osteogenic inducers. Here we show that graphene provides a promising biocompatible scaffold that does not hamper the proliferation of human mesenchymal stem cells (hMSCs) and accelerates their specific differentiation into bone cells. The differentiation rate is comparable to the one achieved with common growth factors, demonstrating graphene’s potential for stem cell research.

827 citations


Journal ArticleDOI
S. Chatrchyan, Vardan Khachatryan, Albert M. Sirunyan, A. Tumasyan  +2268 moreInstitutions (158)
TL;DR: In this article, the transverse momentum balance in dijet and γ/Z+jets events is used to measure the jet energy response in the CMS detector, as well as the transversal momentum resolution.
Abstract: Measurements of the jet energy calibration and transverse momentum resolution in CMS are presented, performed with a data sample collected in proton-proton collisions at a centre-of-mass energy of 7TeV, corresponding to an integrated luminosity of 36pb−1. The transverse momentum balance in dijet and γ/Z+jets events is used to measure the jet energy response in the CMS detector, as well as the transverse momentum resolution. The results are presented for three different methods to reconstruct jets: a calorimeter-based approach, the ``Jet-Plus-Track'' approach, which improves the measurement of calorimeter jets by exploiting the associated tracks, and the ``Particle Flow'' approach, which attempts to reconstruct individually each particle in the event, prior to the jet clustering, based on information from all relevant subdetectors

750 citations


Journal ArticleDOI
TL;DR: The latest advances in VR technology and its applications in neuroscience research are reviewed, which provides a high degree of control over the therapeutic experience.
Abstract: Virtual reality (VR) environments are increasingly being used by neuroscientists to simulate natural events and social interactions. VR creates interactive, multimodal sensory stimuli that offer unique advantages over other approaches to neuroscientific research and applications. VR's compatibility with imaging technologies such as functional MRI allows researchers to present multimodal stimuli with a high degree of ecological validity and control while recording changes in brain activity. Therapists, too, stand to gain from progress in VR technology, which provides a high degree of control over the therapeutic experience. Here we review the latest advances in VR technology and its applications in neuroscience research.

740 citations


Journal ArticleDOI
TL;DR: It is suggested that graphene has a unique surface property that can promote the differentiation of hNSCs toward neurons rather than glia, which should open up tremendous opportunities in stem cell research, neuroscience, and regenerative medicine.
Abstract: However, most previous studies report that hNSCs, without biochemical motifs or co-culturing, differentiated more towards glial cells than neurons. [ 6–8 ] On the other hand, although graphene has attracted much interest for biological applications due to its exotic properties such as biocompatibility, electric conductivity, and transparency, [ 9–12 ] it has not been explored for neural stem cell behavior, yet. Herein, we report a graphene substrate that enhanced the differentiation of hNSCs into neurons. Microarray studies were performed to explore a plausible explanation for this effect. Furthermore, we demonstrated an electrical stimulation on the cells differentiated from hNSCs using graphene as a transparent electrode. Our fi ndings suggest that graphene has a unique surface property that can promote the differentiation of hNSCs toward neurons rather than glia, which should open up tremendous opportunities in stem cell research, neuroscience, and regenerative medicine. Our experimental procedure is summarized in Figure 1 . Graphene was synthesized on a large scale and transferred onto a glass substrate, following a previously reported method (see also Figure S1 and S2 in the Supporting Information). [ 10,11 ] The graphene fi lm on glass was then placed into a laminin solution (20 μ g mL − 1 in culture media for 4 h) so that laminin molecules adhered to both the graphene and the glass and helped hNSC attachment. The hNSCs were seeded on the substrate

649 citations


Journal ArticleDOI
TL;DR: In this article, the authors studied the effect of collision centrality on the transverse momentum of PbPb collisions at the LHC with a data sample of 6.7 inverse microbarns.
Abstract: Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 6.7 inverse microbarns. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching. The observed effect extends from the lower cut-off used in this study (jet transverse momentum = 120 GeV/c) up to the statistical limit of the available data sample (jet transverse momentum approximately 210 GeV/c). Correlations of charged particle tracks with jets indicate that the momentum imbalance is accompanied by a softening of the fragmentation pattern of the second most energetic, away-side jet. The dijet momentum balance is recovered when integrating low transverse momentum particles distributed over a wide angular range relative to the direction of the away-side jet.

621 citations


Journal ArticleDOI
TL;DR: In this randomized trial involving patients with unprotected left main coronary artery stenosis, PCI with sirolimus-eluting stents was shown to be noninferior to CABG with respect to major adverse cardiac or cerebrovascular events, but the results cannot be considered clinically directive.
Abstract: Background Percutaneous coronary intervention (PCI) is increasingly used to treat unprotected left main coronary artery stenosis, although coronary-artery bypass grafting (CABG) has been considered to be the treatment of choice. Methods We randomly assigned patients with unprotected left main coronary artery stenosis to undergo CABG (300 patients) or PCI with sirolimus-eluting stents (300 patients). Using a wide margin for noninferiority, we compared the groups with respect to the primary composite end point of major adverse cardiac or cerebrovascular events (death from any cause, myocardial infarction, stroke, or ischemia-driven target-vessel revascularization) at 1 year. Event rates at 2 years were also compared between the two groups. Results The primary end point occurred in 26 patients assigned to PCI as compared with 20 patients assigned to CABG (cumulative event rate, 8.7% vs. 6.7%; absolute risk difference, 2.0 percentage points; 95% confidence interval [CI], −1.6 to 5.6; P=0.01 for noninferiority...

620 citations


Journal ArticleDOI
TL;DR: The available data on nuclear fusion cross sections important to energy generation in the Sun and other hydrogen-burning stars and to solar neutrino production are summarized and critically evaluated in this article.
Abstract: The available data on nuclear fusion cross sections important to energy generation in the Sun and other hydrogen-burning stars and to solar neutrino production are summarized and critically evaluated. Recommended values and uncertainties are provided for key cross sections, and a recommended spectrum is given for {sup 8}B solar neutrinos. Opportunities for further increasing the precision of key rates are also discussed, including new facilities, new experimental techniques, and improvements in theory. This review, which summarizes the conclusions of a workshop held at the Institute for Nuclear Theory, Seattle, in January 2009, is intended as a 10-year update and supplement to 1998, Rev. Mod. Phys. 70, 1265.

Journal ArticleDOI
17 Mar 2011-Nature
TL;DR: Findings reveal a miRNA-independent cell survival function for DICER1 involving retrotransposon transcript degradation, show that Alu RNA can directly cause human pathology, and identify new targets for a major cause of blindness.
Abstract: Geographic atrophy (GA), an untreatable advanced form of age-related macular degeneration, results from retinal pigmented epithelium (RPE) cell degeneration. Here we show that the microRNA (miRNA)-processing enzyme DICER1 is reduced in the RPE of humans with GA, and that conditional ablation of Dicer1, but not seven other miRNA-processing enzymes, induces RPE degeneration in mice. DICER1 knockdown induces accumulation of Alu RNA in human RPE cells and Alu-like B1 and B2 RNAs in mouse RPE. Alu RNA is increased in the RPE of humans with GA, and this pathogenic RNA induces human RPE cytotoxicity and RPE degeneration in mice. Antisense oligonucleotides targeting Alu/B1/B2 RNAs prevent DICER1 depletion-induced RPE degeneration despite global miRNA downregulation. DICER1 degrades Alu RNA, and this digested Alu RNA cannot induce RPE degeneration in mice. These findings reveal a miRNA-independent cell survival function for DICER1 involving retrotransposon transcript degradation, show that Alu RNA can directly cause human pathology, and identify new targets for a major cause of blindness.

Journal ArticleDOI
TL;DR: SMILE chemotherapy is an effective treatment for newly diagnosed stage IV, relapsed or refractory ENKL and myelosuppression and infection during the treatment should be carefully managed.
Abstract: Purpose To explore a more effective treatment for newly diagnosed stage IV, relapsed, or refractory extranodal natural killer/T-cell lymphoma, nasal type (ENKL), we conducted a phase II study of the steroid (dexamethasone), methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) regimen. Patients and Methods Patients with newly diagnosed stage IV, relapsed, or refractory disease and a performance status of 0 to 2 were eligible. Two cycles of SMILE chemotherapy were administered as the protocol treatment. The primary end point was the overall response rate (ORR) after the protocol treatment. Results A total of 38 eligible patients were enrolled. The median age was 47 years (range, 16 to 67 years), and the male:female ratio was 21:17. The disease status was newly diagnosed stage IV in 20 patients, first relapse in 14 patients, and primary refractory in four patients. The eligibility was revised to include lymphocyte counts of 500/μL or more because the first two patients died from infections. No tre...

Journal ArticleDOI
TL;DR: In this paper, Fowler-Nordheim tunneling was used for atomically flat and ultrathin hexagonal boron nitride (h-BN) on gold-coated mica using conductive atomic force microscopy.
Abstract: Electron tunneling through atomically flat and ultrathin hexagonal boron nitride (h-BN) on gold-coated mica was investigated using conductive atomic force microscopy. Low-bias direct tunneling was observed in mono-, bi-, and tri-layer h-BN. For all thicknesses, Fowler-Nordheim tunneling (FNT) occurred at high bias, showing an increase of breakdown voltage with thickness. Based on the FNT model, the barrier height for tunneling (3.07 eV) and dielectric strength (7.94 MV/cm) of h-BN are obtained; these values are comparable to those of SiO2.

Journal ArticleDOI
TL;DR: In this paper, a novel MPPT method capable of RMPPT under partially shaded conditions (PSCs) is proposed, which is analyzed according to the RMPP position and verified by simulation and experimental results.
Abstract: Conventional popular maximum power point tracking (MPPT) methods are effective under uniform solar irradiance. However, under solar irradiance mismatching conditions [partially shaded conditions (PSCs)], these MPPTs can fail for real MPPT (RMPPT), because multiple local maxima can be exhibited on the power-voltage characteristic curve. Although some researchers have worked on RMPPT under partial shading conditions, the methods have some drawbacks in terms of complexity and requirements for additional circuits, etc. In this paper, a novel MPPT method capable of RMPPT under PSCs is proposed. The performance of the proposed MPPT method is analyzed according to the RMPP position and is verified by simulation and experimental results.

Journal ArticleDOI
12 May 2011-ACS Nano
TL;DR: Graphene films grown on Cu and Ni metal catalysts by chemical vapor deposition and transferred onto the SiO(2)/Si substrate effectively reduced the adhesion and friction forces, and multilayer graphene films that were a few nanometers thick had low coefficients of friction comparable to that of bulk graphite.
Abstract: As an atomically thin material with low surface energy, graphene is an excellent candidate for reducing adhesion and friction when coated on various surfaces. Here, we demonstrate the superior adhesion and frictional characteristics of graphene films which were grown on Cu and Ni metal catalysts by chemical vapor deposition and transferred onto the SiO2/Si substrate. The graphene films effectively reduced the adhesion and friction forces, and multilayer graphene films that were a few nanometers thick had low coefficients of friction comparable to that of bulk graphite.

Journal ArticleDOI
TL;DR: In this paper, the authors compared clinical features and treatment outcomes between patients with M. abscessus lung disease and those with massiliense lung disease, and found that the clinical and radiographic manifestations of disease caused by each species were similar.
Abstract: Rationale: Mycobacterium massiliense has been recognized as a separate species from Mycobacterium abscessus; however, little is known regarding the clinical impact of this differentiation.Objectives: To compare clinical features and treatment outcomes between patients with M. abscessus lung disease and those with M. massiliense lung disease.Methods: We performed molecular identification of stored clinical isolates of M. abscessus complex and compared clinical characteristics and treatment outcomes between 64 patients with M. abscessus lung disease and 81 patients with M. massiliense lung disease.Measurements and Main Results: The clinical and radiographic manifestations of disease caused by each species were similar. Standardized combination antibiotic therapy, including a clarithromycin-containing regimen in combination with an initial 4-week course of cefoxitin and amikacin, was given to 57 patients (24 with M. abscessus and 33 with M. massiliense) for more than 12 months. The proportion of patients wit...

Journal ArticleDOI
TL;DR: Graphene-based, flexible, transparent heaters based on large-scale graphene films synthesized by chemical vapor deposition on Cu foils show sheet resistance as low as ∼43 Ohm/sq with ∼89% optical transmittance, which are ideal as low-voltage transparentheaters.
Abstract: We demonstrate high-performance, flexible, transparent heaters based on large-scale graphene films synthesized by chemical vapor deposition on Cu foils. After multiple transfers and chemical doping processes, the graphene films show sheet resistance as low as ∼43 Ohm/sq with ∼89% optical transmittance, which are ideal as low-voltage transparent heaters. Time-dependent temperature profiles and heat distribution analyses show that the performance of graphene-based heaters is superior to that of conventional transparent heaters based on indium tin oxide. In addition, we confirmed that mechanical strain as high as ∼4% did not substantially affect heater performance. Therefore, graphene-based, flexible, transparent heaters are expected to find uses in a broad range of applications, including automobile defogging/deicing systems and heatable smart windows.

Journal ArticleDOI
TL;DR: A new reducing agent system is reported: hydriodic acid with trifluoroacetic acid, which can chemically convert graphene oxide into reduced graphene oxide at temperatures below 0 °C in solution, which is the first achievement to produce reduced grapheneoxide at subzero temperature with a mass production.

Journal ArticleDOI
TL;DR: A new dissipation mechanism in noncollinear spin textures that can lead to a much faster spin relaxation than Gilbert damping is found.
Abstract: We study the collective dynamics of the Skyrmion crystal in thin films of ferromagnetic metals resulting from the nontrivial Skyrmion topology. It is shown that the current-driven motion of the crystal reduces the topological Hall effect and the Skyrmion trajectories bend away from the direction of the electric current (the Skyrmion Hall effect). We find a new dissipation mechanism in noncollinear spin textures that can lead to a much faster spin relaxation than Gilbert damping, calculate the dispersion of phonons in the Skyrmion crystal, and discuss the effects of impurity pinning of Skyrmions.

Journal ArticleDOI
TL;DR: In this paper, a review of thin-film barrier technologies for flexible organic light emitting diode (OLED) devices is provided, where the significance of the device structure, permeation rate measurement, and proposed permeation mechanism are discussed.
Abstract: Flexible organic light emitting diode (OLED) will be the ultimate display technology to customers and industries in the near future but the challenges are still being unveiled one by one. Thin-film encapsulation (TFE) technology is the most demanding requirement to prevent water and oxygen permeation into flexible OLED devices. As a polymer substrate does not offer the same barrier performance as glass, the TFE should be developed on both the bottom and top side of the device layers for sufficient lifetimes. This work provides a review of promising thin-film barrier technologies as well as the basic gas diffusion background. Topics include the significance of the device structure, permeation rate measurement, proposed permeation mechanism, and thin-film deposition technologies (Vitex system and atomic layer deposition (ALD)/molecular layer deposition (MLD)) for effective barrier films.

Journal ArticleDOI
K. Abe1, Y. Hayato1, T. Iida1, M. Ikeda1, M. Ikeda2, C. Ishihara1, K. Iyogi1, J. Kameda1, Ken-ichiro Kobayashi1, Yusuke Koshio1, Y. Kozuma1, M. Miura1, S. Moriyama1, Masayuki Nakahata1, S. Nakayama1, Y. Obayashi1, H. Ogawa1, Hiroyuki Sekiya1, Masato Shiozawa1, Yasunari Suzuki1, Atsushi Takeda1, Y. Takenaga1, Koh Ueno1, K. Ueshima, Hiroshi Watanabe, S. Yamada1, T. Yokozawa1, S. Hazama1, H. Kaji1, Takaaki Kajita1, K. Kaneyuki1, T. McLachlan1, Ko Okumura1, Y. Shimizu1, N. Tanimoto1, M. R. Vagins1, M. R. Vagins3, L. Labarga4, L. M. Magro4, Frédéric Dufour5, E. Kearns1, E. Kearns5, Michael Litos5, J. L. Raaf5, J. L. Stone1, J. L. Stone5, L. R. Sulak5, W. Wang6, W. Wang5, M. Goldhaber7, K. Bays3, David William Casper3, J. P. Cravens3, W. R. Kropp3, S. Mine3, C. Regis3, A. L. Renshaw3, M. B. Smy1, M. B. Smy3, H. W. Sobel3, H. W. Sobel1, K. S. Ganezer8, John Hill8, W. E. Keig8, J. S. Jang9, J. Y. Kim9, I. T. Lim9, Justin Albert10, R. A. Wendell10, T. Wongjirad10, Kate Scholberg10, Kate Scholberg1, C. W. Walter10, C. W. Walter1, T. Ishizuka11, S. Tasaka12, John G. Learned, S. Matsuno, Y. Watanabe13, Takehisa Hasegawa, T. Ishida, T. Ishii, T. Kobayashi, T. Nakadaira, Koji Nakamura1, K. Nishikawa, H. Nishino, Yuichi Oyama, Ken Sakashita, T. Sekiguchi, T. Tsukamoto, A. T. Suzuki14, Y. Takeuchi1, Y. Takeuchi14, A. Minamino2, Tsuyoshi Nakaya2, Tsuyoshi Nakaya1, Y. Fukuda15, Yoshitaka Itow16, G. Mitsuka16, T. Tanaka16, C. K. Jung17, G. D. Lopez17, C. McGrew17, R. Terri17, C. Yanagisawa17, N. Tamura18, Hirokazu Ishino19, A. Kibayashi19, S. Mino19, Takaaki Mori19, Makoto Sakuda19, H. Toyota19, Y. Kuno20, Minoru Yoshida20, S. B. Kim21, B. S. Yang21, H. Okazawa22, Y. Choi23, K. Nishijima24, Y. Yokosawa24, M. Koshiba1, Y. Totsuka1, Masashi Yokoyama1, Song Chen25, Y. Heng25, Zishuo Yang25, Haoxiong Zhang25, D. Kielczewska26, P. Mijakowski26, K. Connolly27, M. Dziomba27, E. Thrane27, E. Thrane28, R. J. Wilkes27 
TL;DR: The results of the third phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first and second phase results in this article, where improved detector calibrations, a full detector simulation, and improved analysis methods are estimated to be approximately 2.1%, which is about two thirds of the systematic uncertainty for the first phase.
Abstract: The results of the third phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first and second phase results. With improved detector calibrations, a full detector simulation, and improved analysis methods, the systematic uncertainty on the total neutrino flux is estimated to be $\ifmmode\pm\else\textpm\fi{}2.1%$, which is about two thirds of the systematic uncertainty for the first phase of Super-Kamiokande. The observed $^{8}\mathrm{B}$ solar flux in the 5.0 to 20 MeV total electron energy region is $2.32\ifmmode\pm\else\textpm\fi{}0.04(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.05(\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{sec}}^{\ensuremath{-}1}$ under the assumption of pure electron-flavor content, in agreement with previous measurements. A combined oscillation analysis is carried out using SK-I, II, and III data, and the results are also combined with the results of other solar neutrino experiments. The best-fit oscillation parameters are obtained to be ${sin }^{2}{\ensuremath{\theta}}_{12}={0.30}_{\ensuremath{-}0.01}^{+0.02}({tan }^{2}{\ensuremath{\theta}}_{12}={0.42}_{\ensuremath{-}0.02}^{+0.04})$ and $\ensuremath{\Delta}{m}_{21}^{2}={6.2}_{\ensuremath{-}1.9}^{+1.1}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. Combined with KamLAND results, the best-fit oscillation parameters are found to be ${sin }^{2}{\ensuremath{\theta}}_{12}=0.31\ifmmode\pm\else\textpm\fi{}0.01({tan }^{2}{\ensuremath{\theta}}_{12}=0.44\ifmmode\pm\else\textpm\fi{}0.03)$ and $\ensuremath{\Delta}{m}_{21}^{2}=7.6\ifmmode\pm\else\textpm\fi{}0.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. The $^{8}\mathrm{B}$ neutrino flux obtained from global solar neutrino experiments is $5.3\ifmmode\pm\else\textpm\fi{}0.2(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$, while the $^{8}\mathrm{B}$ flux becomes $5.1\ifmmode\pm\else\textpm\fi{}0.1(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ by adding KamLAND results. In a three-flavor analysis combining all solar neutrino experiments, the upper limit of ${sin }^{2}{\ensuremath{\theta}}_{13}$ is 0.060 at 95% C.L.. After combination with KamLAND results, the upper limit of ${sin }^{2}{\ensuremath{\theta}}_{13}$ is found to be 0.059 at 95% C.L.

Journal ArticleDOI
TL;DR: This research was supported by Future-based Technology Development Program (Nano Fields, 2010-0029321) and the WCU (World Class University) program (R32-2008-000-10142-0) through the NRF of Korea funded by the MEST.
Abstract: This research was supported by Future-based Technology Development Program (Nano Fields, 2010-0029321) and the WCU (World Class University) program (R32-2008-000-10142-0) through the NRF of Korea funded by the MEST. J. H. Park acknowledges the support from NRF of Korea funded by the MEST (NRF-2009- C1AAA001-2009-0094157, 2011-0006268). Research at UCSB was supported by the US Army General Technical Services (LLC/GTS-S- 09-1-196) and by the Department of Energy (BES-DOE- ER46535).

Journal ArticleDOI
TL;DR: Although the best monolayer graphene was grown from polished Cu with a low sheet resistance of 260 Ω/sq, a small portion of multilayers were also formed near the impurity particles or locally protruded parts.
Abstract: We report that highly crystalline graphene can be obtained from well-controlled surface morphology of the copper substrate. Flat copper surface was prepared by using a chemical mechanical polishing method. At early growth stage, the density of graphene nucleation seeds from polished Cu film was much lower and the domain sizes of graphene flakes were larger than those from unpolished Cu film. At later growth stage, these domains were stitched together to form monolayer graphene, where the orientation of each domain crystal was unexpectedly not much different from each other. We also found that grain boundaries and intentionally formed scratched area play an important role for nucleation seeds. Although the best monolayer graphene was grown from polished Cu with a low sheet resistance of 260 Ω/sq, a small portion of multilayers were also formed near the impurity particles or locally protruded parts.

Journal ArticleDOI
TL;DR: It is confirmed that MRSA infections in the community have been increasing in Asian countries and data suggest that various MRSA clones have spread between the community and hospitals as well as between countries.
Abstract: Objectives Methicillin-resistant Staphylococcus aureus (MRSA) is highly prevalent in hospitals in many Asian countries. Recent emergence of community-associated (CA) MRSA worldwide has added another serious concern to the epidemiology of S. aureus infections. To understand the changing epidemiology of S. aureus infections in Asian countries, we performed a prospective, multinational surveillance study with molecular typing analysis. Methods We evaluated the prevalence of methicillin resistance in S. aureus isolates in CA and healthcare-associated (HA) infections, and performed molecular characterization and antimicrobial susceptibility tests of MRSA isolates. Results MRSA accounted for 25.5% of CA S. aureus infections and 67.4% of HA infections. Predominant clones of CA-MRSA isolates were ST59-MRSA-SCCmec type IV-spa type t437, ST30-MRSA-SCCmec type IV-spa type t019 and ST72-MRSA-SCCmec type IV-spa type t324. Previously established nosocomial MRSA strains including sequence type (ST) 239 and ST5 clones were found among CA-MRSA isolates from patients without any risk factors for HA-MRSA infection. CA-MRSA clones such as ST59, ST30 and ST72 were also isolated from patients with HA infections. Conclusions Our findings confirmed that MRSA infections in the community have been increasing in Asian countries. Data also suggest that various MRSA clones have spread between the community and hospitals as well as between countries.

Journal ArticleDOI
27 Jan 2011-Neuron
TL;DR: A systematic analysis of how bitter taste is encoded by the major taste organ of the Drosophila head, the labellum, reveals a degree of complexity that greatly expands the capacity of the system to encode bitter taste.


Journal ArticleDOI
11 Oct 2011-ACS Nano
TL;DR: Poly(ethylene glycol) (PEG)-conjugated hyaluronic acid nanoparticles (P-HA-NPs) showed promising potential as a drug carrier for cancer therapy.
Abstract: Tumor targetability and site-specific drug release of therapeutic nanoparticles are key factors for effective cancer therapy. In this study, poly(ethylene glycol) (PEG)-conjugated hyaluronic acid nanoparticles (P-HA-NPs) were investigated as carriers for anticancer drugs including doxorubicin and camptothecin (CPT). P-HA-NPs were internalized into cancer cells (SCC7 and MDA-MB-231) via receptor-mediated endocytosis, but were rarely taken up by normal fibroblasts (NIH-3T3). During in vitro drug release tests, P-HA-NPs rapidly released drugs when incubated with cancer cells, extracts of tumor tissues, or the enzyme Hyal-1, which is abundant in the intracellular compartments of cancer cells. CPT-loaded P-HA-NPs (CPT-P-HA-NPs) showed dose-dependent cytotoxicity to cancer cells (MDA-MB-231, SCC7, and HCT 116) and significantly lower cytotoxicity against normal fibroblasts (NIH-3T3) than free CPT. Unexpectedly, high concentrations of CPT-P-HA-NPs demonstrated greater cytotoxicity to cancer cells than free CPT. ...

Journal ArticleDOI
TL;DR: This work presents stretchable, printable, and transparent transistors composed of monolithically patterned graphene films, capable of use as semiconducting channels as well as the source/drain electrodes.
Abstract: With the emergence of human interface technology, the development of new applications based on stretchable electronics such as conformal biosensors and rollable displays are required. However, the difficulty in developing semiconducting materials with high stretchability required for such applications has restricted the range of applications of stretchable electronics. Here, we present stretchable, printable, and transparent transistors composed of monolithically patterned graphene films. This material offers excellent mechanical, electrical, and optical properties, capable of use as semiconducting channels as well as the source/drain electrodes. Such monolithic graphene transistors show hole and electron mobilities of 1188 ± 136 and 422 ± 52 cm2/(V s), respectively, with stable operation at stretching up to 5% even after 1000 or more cycles.

Journal ArticleDOI
TL;DR: It is suggested that tumor-derived exosomes can contribute to progression and malignancy of tumor by converting MSCs within tumor stroma into tumor-associated myofibroblasts with increased expression of α-SMA in the tumor microenvironment.
Abstract: Exosomes are small membrane vesicles secreted into the extracellular environment by various types of cells, including tumor cells. Exosomes are enriched with a discrete set of cellular proteins, and therefore expected to exert diverse biological functions according to cell origin. Mesenchymal stem cells (MSCs) possess the potential for differentiation into multilineages and can also function as precursors for tumor stroma including myofibroblast that provides a favorable environment for tumor progression. Although a close relationship between tumor cells and MSCs in a neoplastic tumor microenvironment has already been revealed, how this communication works is poorly understood. In this study, we investigated the influence of tumor cell-derived exosomes on MSCs by treating adipose tissue-derived MSCs (ADSCs) with breast cancer-derived exosomes. The exosome-treated ADSCs exhibited the phenotypes of tumor-associated myofibroblasts with increased expression of α-SMA. Exosome treatment also induced increased expression of tumor-promoting factors SDF-1, VEGF, CCL5 and TGFβ. This phenomenon was correlated with increased expression of TGFβ receptor I and II. Analysis of SMAD2, a key player in the TGFβ receptor-mediated SMAD pathway, revealed that its phosphorylation was increased by exosome treatment and was inhibited by treatment with SB431542, an inhibitor of the SMAD-mediated pathway, resulting in decreased expression of α-SMA. Taken together, our results show that tumor-derived exosomes induced the myofibroblastic phenotype and functionality in ADSCs via the SMAD-mediated signaling pathway. In conclusion, this study suggests that tumor-derived exosomes can contribute to progression and malignancy of tumor cells by converting MSCs within tumor stroma into tumor-associated myofibroblasts in the tumor microenvironment.