bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exciton–polaritons in van der Waals heterostructures embedded in tunable microcavities
Authors: Dufferwiel S. , Schwarz S. , Withers F. , Trichet A. A. P. , Li F. , Sich M. , Del Pozo-Zamudio O. , Clark C. , Nalitov A. , Solnyshkov D. D. , Malpuech G. , Novoselov K. S. , Smith J. M. , Skolnick M. S. , Krizhanovskii D. N. , Tartakovskii A. I. 
Published: October 2015

AbstractLayered materials can be assembled vertically to fabricate a new class of van der Waals heterostructures a few atomic layers thick, compatible with a wide range of substrates and optoelectronic device geometries, enabling new strategies for control of light–matter coupling. Here, we incorporate molybdenum diselenide/hexagonal boron nitride (MoSe2/hBN) quantum wells in a tunable optical microcavity. Part-light–part-matter polariton eigenstates are observed as a result of the strong coupling between MoSe2 excitons and cavity photons, evidenced from a clear anticrossing between the neutral exciton and the cavity modes with a splitting of 20 meV for a single MoSe2 monolayer, enhanced to 29 meV in MoSe2/hBN/MoSe2 double-quantum wells. The splitting at resonance provides an estimate of the exciton radiative lifetime of 0.4 ps. Our results pave the way for room-temperature polaritonic devices based on multiple-quantum-well van der Waals heterostructures, where polariton condensation and electrical polariton injection through the incorporation of graphene contacts may be realized.
Strongly enhanced oxygen ion transport through samarium-doped CeO2 nanopillars in nanocomposite films
Authors: Yang Sang Mo , Lee Shinbuhm , Jian Jie , Zhang Wenrui , Lu Ping , Jia Quanxi , Wang Haiyan , Won Noh Tae , Kalinin Sergei V. , MacManus‐Driscoll Judith L. 
Published: October 2015

AbstractEnhancement of oxygen ion conductivity in oxides is important for low-temperature (<500 °C) operation of solid oxide fuel cells, sensors and other ionotronic devices. While huge ion conductivity has been demonstrated in planar heterostructure films, there has been considerable debate over the origin of the conductivity enhancement, in part because of the difficulties of probing buried ion transport channels. Here we create a practical geometry for device miniaturization, consisting of highly crystalline micrometre-thick vertical nanocolumns of Sm-doped CeO2 embedded in supporting matrices of SrTiO3. The ionic conductivity is higher by one order of magnitude than plain Sm-doped CeO2 films. By using scanning probe microscopy, we show that the fast ion-conducting channels are not exclusively restricted to the interface but also are localized at the Sm-doped CeO2 nanopillars. This work offers a pathway to realize spatially localized fast ion transport in oxides of micrometre thickness.
Kaempferol Identified by Zebrafish Assay and Fine Fractionations Strategy from Dysosma versipellis Inhibits Angiogenesis through VEGF and FGF Pathways
Authors: Liang Fang , Han Yuxiang , Gao Hao , Xin Shengchang , Chen Shaodan , Wang Nan , Qin Wei , Zhong Hanbing , Lin Shuo , Yao Xinsheng , Li Song 
Published: October 2015

AbstractNatural products are a rich resource for the discovery of therapeutic substances. By directly using 504 fine fractions from isolated traditional Chinese medicine plants, we performed a transgenic zebrafish based screen for anti-angiogenesis substances. One fraction, DYVE-D3, was found to inhibit the growth of intersegmental vessels in the zebrafish vasculature. Bioassay-guided isolation of DYVE-D3 indicates that the flavonoid kaempferol was the active substance. Kaempferol also inhibited the proliferation and migration of HUVECs in vitro. Furthermore, we found that kaempferol suppressed angiogenesis through inhibiting VEGFR2 expression, which can be enhanced by FGF inhibition. In summary, this study shows that the construction of fine fraction libraries allows efficient identification of active substances from natural products.
Computational speed-up with a single qudit
Authors: Gedik Z. , Silva I. A. , Çakmak B. , Karpat G. , Vidoto E. L. G. , Soares-Pinto D. O. , deAzevedo E. R. , Fanchini F. F. 
Published: October 2015

AbstractQuantum algorithms are known for providing more efficient solutions to certain computational tasks than any corresponding classical algorithm. Here we show that a single qudit is sufficient to implement an oracle based quantum algorithm, which can solve a black-box problem faster than any classical algorithm. For 2d permutation functions defined on a set of d elements, deciding whether a given permutation is even or odd, requires evaluation of the function for at least two elements. We demonstrate that a quantum circuit with a single qudit can determine the parity of the permutation with only one evaluation of the function. Our algorithm provides an example for quantum computation without entanglement since it makes use of the pure state of a qudit. We also present an experimental realization of the proposed quantum algorithm with a quadrupolar nuclear magnetic resonance using a single four-level quantum system, i.e., a ququart.
Network modelling reveals the mechanism underlying colitis-associated colon cancer and identifies novel combinatorial anti-cancer targets
Authors: Lu Junyan , Zeng Hanlin , Liang Zhongjie , Chen Limin , Zhang Liyi , Zhang Hao , Liu Hong , Jiang Hualiang , Shen Bairong , Huang Ming , Geng Meiyu , Spiegel Sarah , Luo Cheng 
Published: October 2015

AbstractThe connection between inflammation and tumourigenesis has been well established. However, the detailed molecular mechanism underlying inflammation-associated tumourigenesis remains unknown because this process involves a complex interplay between immune microenvironments and epithelial cells. To obtain a more systematic understanding of inflammation-associated tumourigenesis as well as to identify novel therapeutic approaches, we constructed a knowledge-based network describing the development of colitis-associated colon cancer (CAC) by integrating the extracellular microenvironment and intracellular signalling pathways. Dynamic simulations of the CAC network revealed a core network module, including P53, MDM2 and AKT, that may govern the malignant transformation of colon epithelial cells in a pro-tumor inflammatory microenvironment. Furthermore, in silico mutation studies and experimental validations led to a novel finding that concurrently targeting ceramide and PI3K/AKT pathway by chemical probes or marketed drugs achieves synergistic anti-cancer effects. Overall, our network model can guide further mechanistic studies on CAC and provide new insights into the design of combinatorial cancer therapies in a rational manner.
Regulation of the unfolded protein response via S-nitrosylation of sensors of endoplasmic reticulum stress
Authors: Nakato Ryosuke , Ohkubo Yu , Konishi Akari , Shibata Mari , Kaneko Yuki , Iwawaki Takao , Nakamura Tomohiro , Lipton Stuart A. , Uehara Takashi 
Published: October 2015

AbstractProtein S-nitrosylation modulates important cellular processes, including neurotransmission, vasodilation, proliferation and apoptosis in various cell types. We have previously reported that protein disulfide isomerase (PDI) is S-nitrosylated in brains of patients with sporadic neurodegenerative diseases. This modification inhibits PDI enzymatic activity and consequently leads to the accumulation of unfolded/misfolded proteins in the endoplasmic reticulum (ER) lumen. Here, we describe S-nitrosylation of additional ER pathways that affect the unfolded protein response (UPR) in cell-based models of Parkinson’s disease (PD). We demonstrate that nitric oxide (NO) can S-nitrosylate the ER stress sensors IRE1α and PERK. While S-nitrosylation of IRE1α inhibited its ribonuclease activity, S-nitrosylation of PERK activated its kinase activity and downstream phosphorylation/inactivation or eIF2α. Site-directed mutagenesis of IRE1α(Cys931) prevented S-nitrosylation and inhibition of its ribonuclease activity, indicating that Cys931 is the predominant site of S-nitrosylation. Importantly, cells overexpressing mutant IRE1α(C931S) were resistant to NO-induced damage. Our findings show that nitrosative stress leads to dysfunctional ER stress signaling, thus contributing to neuronal cell death.
Efficacy and HIV drug resistance profile of second-line ART among patients having received long-term first-line regimens in rural China
Authors: Wang Jing , Wang Zhe , Liu Jia , Yue Yanchao , Yang Shimei , Huang Huimin , He Cui , Liao Lingjie , Xing Hui , Ruan Yuhua , Shao Yiming 
Published: October 2015

AbstractAntiretroviral therapy has significantly expanded and an increased proportion of patients have switched to second-line regimens in China. We describe the outcomes of second-line therapy among patients having received long-term first-line ART. A prospective follow-up study was conducted in rural areas in China. We compared the virological, immunological outcomes and genotypic drug resistance (DR) profiles before and after regimen switches. A total of 303 patients were enrolled, 283 (93.4%) were retained at 12 months. Of 90 participants with HIV-RNA ≥ 1000 copies/ml before switch, the proportion of viral load (VL) ≥ 1000 copies/ml at 6 and 12 months was 49.4% and 43.9%, respectively. Of 213 patients with HIV-RNA < 1000 copies/ml before switch, the proportion of VL ≥ 1000 copies/ml at 6 and 12 months was 4.8% and 6.5%, respectively. The rates of drug resistance to NNRTIs, NRTIs, PIs decreased from 65.5%, 53.3% and 1.1% before regimen switch to 26.8%, 18.3% and 0% at 12 months, respectively. DDI-based initial ART regimens and missing doses in past month were associated with HIV RNA ≥ 1000 copies/ml at 12 months. The results showed that patients having received long-term first-line ART and experiencing virological failure had good virological outcomes after switching to second-line treatment in China.
FSP1+ fibroblast subpopulation is essential for the maintenance and regeneration of medullary thymic epithelial cells
Authors: Sun Lina , Sun Chenming , Liang Zhanfeng , Li Hongran , Chen Lin , Luo Haiying , Zhang Hongmei , Ding Pengbo , Sun Xiaoning , Qin Zhihai , Zhao Yong 
Published: October 2015

AbstractThymic epithelial cells (TECs) form a 3-dimentional network supporting thymocyte development and maturation. Besides epithelium and thymocytes, heterogeneous fibroblasts are essential components in maintaining thymic microenvironments. However, thymic fibroblast characteristics, development and function remain to be determined. We herein found that thymic non-hematopoietic CD45-FSP1+ cells represent a unique Fibroblast specific protein 1 (FSP1)—fibroblast-derived cell subset. Deletion of these cells in FSP1-TK transgenic mice caused thymus atrophy due to the loss of TECs, especially mature medullary TECs (MHCIIhigh, CD80+ and Aire+). In a cyclophosphamide-induced thymus injury and regeneration model, lack of non-hematopoietic CD45-FSP1+ fibroblast subpopulation significantly delayed thymus regeneration. In fact, thymic FSP1+ fibroblasts released more IL-6, FGF7 and FSP1 in the culture medium than their FSP1- counterparts. Further experiments showed that the FSP1 protein could directly enhance the proliferation and maturation of TECs in the in vitro culture systems. FSP1 knockout mice had significantly smaller thymus size and less TECs than their control. Collectively, our studies reveal that thymic CD45-FSP1+ cells are a subpopulation of fibroblasts, which is crucial for the maintenance and regeneration of TECs especially medullary TECs through providing IL-6, FGF7 and FSP1.
The thermodynamic cost of driving quantum systems by their boundaries
Authors: Barra Felipe 
Published: October 2015

AbstractThe laws of thermodynamics put limits to the efficiencies of thermal machines. Analogues of these laws are now established for quantum engines weakly and passively coupled to the environment providing a framework to find improvements to their performance. Systems whose interaction with the environment is actively controlled do not fall in that framework. Here we consider systems actively and locally coupled to the environment, evolving with a so-called boundary-driven Lindblad equation. Starting from a unitary description of the system plus the environment we simultaneously obtain the Lindblad equation and the appropriate expressions for heat, work and entropy-production of the system extending the framework for the analysis of new and some already proposed, quantum heat engines. We illustrate our findings in spin 1/2 chains and explain why an XX chain coupled in this way to a single heat bath relaxes to thermodynamic-equilibrium while and XY chain does not. Additionally, we show that an XX chain coupled to a left and a right heat baths behaves as a quantum engine, a heater or refrigerator depending on the parameters, with efficiencies bounded by Carnot efficiencies.
Direct tumor recognition by a human CD4+ T-cell subset potently mediates tumor growth inhibition and orchestrates anti-tumor immune responses
Authors: Matsuzaki Junko , Tsuji Takemasa , Luescher Immanuel F. , Shiku Hiroshi , Mineno Junichi , Okamoto Sachiko , Old Lloyd J. , Shrikant Protul , Gnjatic Sacha , Odunsi Kunle 
Published: October 2015

AbstractTumor antigen-specific CD4+ T cells generally orchestrate and regulate immune cells to provide immune surveillance against malignancy. However, activation of antigen-specific CD4+ T cells is restricted at local tumor sites where antigen-presenting cells (APCs) are frequently dysfunctional, which can cause rapid exhaustion of anti-tumor immune responses. Herein, we characterize anti-tumor effects of a unique human CD4+ helper T-cell subset that directly recognizes the cytoplasmic tumor antigen, NY-ESO-1, presented by MHC class II on cancer cells. Upon direct recognition of cancer cells, tumor-recognizing CD4+ T cells (TR-CD4) potently induced IFN-γ-dependent growth arrest in cancer cells. In addition, direct recognition of cancer cells triggers TR-CD4 to provide help to NY-ESO-1-specific CD8+ T cells by enhancing cytotoxic activity and improving viability and proliferation in the absence of APCs. Notably, the TR-CD4 either alone or in collaboration with CD8+ T cells significantly inhibited tumor growth in vivo in a xenograft model. Finally, retroviral gene-engineering with T cell receptor (TCR) derived from TR-CD4 produced large numbers of functional TR-CD4. These observations provide mechanistic insights into the role of TR-CD4 in tumor immunity and suggest that approaches to utilize TR-CD4 will augment anti-tumor immune responses for durable therapeutic efficacy in cancer patients.
Boletus edulis Nitrite Reductase Reduces Nitrite Content of Pickles and Mitigates Intoxication in Nitrite-intoxicated Mice
Authors: Zhang Weiwei , Tian Guoting , Feng Shanshan , Wong Jack Ho , Zhao Yongchang , Chen Xiao , Wang Hexiang , Ng Tzi Bun 
Published: October 2015

AbstractPickles are popular in China and exhibits health-promoting effects. However, nitrite produced during fermentation adversely affects health due to formation of methemoglobin and conversion to carcinogenic nitrosamine. Fruiting bodies of the mushroom Boletus edulis were capable of inhibiting nitrite production during pickle fermentation. A 90-kDa nitrite reductase (NiR), demonstrating peptide sequence homology to fungal nitrite reductase, was isolated from B. edulis fruiting bodies. The optimum temperature and pH of the enzyme was 45 °C and 6.8, respectively. B. edulis NiR was capable of prolonging the lifespan of nitrite-intoxicated mice, indicating that it had the action of an antidote. The enzyme could also eliminate nitrite from blood after intragastric administration of sodium nitrite and after packaging into capsule, this nitrite-eliminating activity could persist for at least 120 minutes thus avoiding immediate gastric degradation. B. edulis NiR represents the first nitrite reductase purified from mushrooms and may facilitate subsequent applications.
Circularly polarised phosphorescent photoluminescence and electroluminescence of iridium complexes
Authors: Li Tian-Yi , Jing Yi-Ming , Liu Xuan , Zhao Yue , Shi Lin , Tang Zhiyong , Zheng You-Xuan , Zuo Jing-Lin 
Published: October 2015

AbstractNearly all the neutral iridium complexes widely used as dopants in PhOLEDs are racemic mixtures; however, this study observed that these complexes can be separated into stable optically active Λ and ∆ isomers and that their chirality is an intrinsic property. The circularly polarised phosphorescent photoluminescence (CPPPL) signals of Λ/Δ isomers are perfect mirror images with opposite polarisation and equal intensity exhibiting a “handedness” for the polarisation. For the first time, we applied the Λ/Δ iridium isomers as emitters in OLEDs and the circularly polarised phosphorescent electroluminescence (CPPEL) spectra reveal completely positive or negative broad peaks consistent with the CPPPL spectra. The results demonstrate that the Λ/Δ isomers have potential application for 3D OLEDs because they can exhibit high efficiency and luminance and 3D display technology based on circularly polarised light is the most comfortable for the eyes.
Synaptic vesicles contain small ribonucleic acids (sRNAs) including transfer RNA fragments (trfRNA) and microRNAs (miRNA)
Authors: Li Huinan , Wu Cheng , Aramayo Rodolfo , Sachs Matthew S. , Harlow Mark L. 
Published: October 2015

AbstractSynaptic vesicles (SVs) are neuronal presynaptic organelles that load and release neurotransmitter at chemical synapses. In addition to classic neurotransmitters, we have found that synaptic vesicles isolated from the electric organ of Torpedo californica, a model cholinergic synapse, contain small ribonucleic acids (sRNAs), primarily the 5′ ends of transfer RNAs (tRNAs) termed tRNA fragments (trfRNAs). To test the evolutionary conservation of SV sRNAs we examined isolated SVs from the mouse central nervous system (CNS). We found abundant levels of sRNAs in mouse SVs, including trfRNAs and micro RNAs (miRNAs) known to be involved in transcriptional and translational regulation. This discovery suggests that, in addition to inducing changes in local dendritic excitability through the release of neurotransmitters, SVs may, through the release of specific trfRNAs and miRNAs, directly regulate local protein synthesis. We believe these findings have broad implications for the study of chemical synaptic transmission.
Microplastics in Arctic polar waters: the first reported values of particles in surface and sub-surface samples
Authors: Lusher Amy L. , Tirelli Valentina , O’Connor Ian , Officer Rick 
Published: October 2015

AbstractPlastic, as a form of marine litter, is found in varying quantities and sizes around the globe from surface waters to deep-sea sediments. Identifying patterns of microplastic distribution will benefit an understanding of the scale of their potential effect on the environment and organisms. As sea ice extent is reducing in the Arctic, heightened shipping and fishing activity may increase marine pollution in the area. Microplastics may enter the region following ocean transport and local input, although baseline contamination measurements are still required. Here we present the first study of microplastics in Arctic waters, south and southwest of Svalbard, Norway. Microplastics were found in surface (top 16 cm) and sub-surface (6 m depth) samples using two independent techniques. Origins and pathways bringing microplastic to the Arctic remain unclear. Particle composition (95% fibres) suggests they may either result from the breakdown of larger items (transported over large distances by prevailing currents, or derived from local vessel activity), or input in sewage and wastewater from coastal areas. Concurrent observations of high zooplankton abundance suggest a high probability for marine biota to encounter microplastics and a potential for trophic interactions. Further research is required to understand the effects of microplastic-biota interaction within this productive environment.
Polarization induced self-doping in epitaxial Pb(Zr0.20Ti0.80)O3 thin films
Authors: Pintilie Lucian , Ghica Corneliu , Teodorescu Cristian Mihail , Pintilie Ioana , Chirila Cristina , Pasuk Iuliana , Trupina Lucian , Hrib Luminita , Boni Andra Georgia , Georgiana Apostol Nicoleta , Abramiuc Laura Elena , Negrea Raluca , Stefan Mariana , Ghica Daniela 
Published: October 2015

AbstractThe compensation of the depolarization field in ferroelectric layers requires the presence of a suitable amount of charges able to follow any variation of the ferroelectric polarization. These can be free carriers or charged defects located in the ferroelectric material or free carriers coming from the electrodes. Here we show that a self-doping phenomenon occurs in epitaxial, tetragonal ferroelectric films of Pb(Zr0.2Ti0.8)O3, consisting in generation of point defects (vacancies) acting as donors/acceptors. These are introducing free carriers that partly compensate the depolarization field occurring in the film. It is found that the concentration of the free carriers introduced by self-doping increases with decreasing the thickness of the ferroelectric layer, reaching values of the order of 1026 m−3for 10 nm thick films. One the other hand, microscopic investigations show that, for thicknesses higher than 50 nm, the 2O/(Ti+Zr+Pb) atomic ratio increases with the thickness of the layers. These results suggest that the ratio between the oxygen and cation vacancies varies with the thickness of the layer in such a way that the net free carrier density is sufficient to efficiently compensate the depolarization field and to preserve the outward direction of the polarization.
Real-time imaging of hydrogen peroxide dynamics in vegetative and pathogenic hyphae of Fusarium graminearum
Authors: Mentges Michael , Bormann Jörg 
Published: October 2015

AbstractBalanced dynamics of reactive oxygen species in the phytopathogenic fungusFusarium graminearumplay key roles for development and infection. To monitor those dynamics, ratiometric analysis using the novel hydrogen peroxide (H2O2) sensitive fluorescent indicator protein HyPer-2 was established for the first time in phytopathogenic fungi. H2O2changes the excitation spectrum of HyPer-2 with an excitation maximum at 405 nm for the reduced and 488 nm for the oxidized state, facilitating ratiometric readouts with maximum emission at 516 nm. HyPer-2 analyses were performed using a microtiter fluorometer and confocal laser scanning microscopy (CLSM). Addition of external H2O2to mycelia caused a steep and transient increase in fluorescence excited at 488 nm. This can be reversed by the addition of the reducing agent dithiothreitol. HyPer-2 inF. graminearumis highly sensitive and specific to H2O2even in tiny amounts. Hyperosmotic treatment elicited a transient internal H2O2burst. Hence, HyPer-2 is suitable to monitor the intracellular redox balance. Using CLSM, developmental processes like nuclear division, tip growth, septation and infection structure development were analyzed. The latter two processes imply marked accumulations of intracellular H2O2. Taken together, HyPer-2 is a valuable and reliable tool for the analysis of environmental conditions, cellular development and pathogenicity.
Guiding SPPs with PT-symmetry
Authors: Yang Fan , Lei Mei Zhong 
Published: October 2015

AbstractThe concept of parity-time (PT) symmetry in SPPs is proposed and confirmed for the first time in this work. By introducing periodic modulation of the effective refractive index in SPP system, the asymmetric propagation is theoretically predicted and numerically demonstrated. After validation of this concept, we apply it in two applications: PT-waveguide and PT-cloak. Both two applications further illustrate the wide applicability of this concept in SPP system.