bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteomic screening identifies calreticulin as a miR-27a direct target repressing MHC class I cell surface exposure in colorectal cancer
Authors: Colangelo T , Polcaro G , Ziccardi P , Pucci B , Muccillo L , Galgani M , Fucci A , Milone M R , Budillon A , Santopaolo M , Votino C , Pancione M , Piepoli A , Mazzoccoli G , Binaschi M , Bigioni M , Maggi C A , Fassan M , Laudanna C , Matarese G , Sabatino L , Colantuoni V
Published: February 2016

Impairment of the immune response and aberrant expression of microRNAs are emerging hallmarks of tumour initiation/progression, in addition to driver gene mutations and epigenetic modifications. We performed a preliminary survey of independent adenoma and colorectal cancer (CRC) miRnoma data sets and, among the most dysregulated miRNAs, we selected miR-27a and disclosed that it is already upregulated in adenoma and further increases during the evolution to adenocarcinoma. To identify novel genes and pathways regulated by this miRNA, we employed a differential 2DE-DIGE proteome analysis. We showed that miR-27a modulates a group of proteins involved in MHC class I cell surface exposure and, mechanistically, demonstrated that calreticulin is a miR-27a direct target responsible for most downstream effects in epistasis experiments. In vitro miR-27a affected cell proliferation and angiogenesis; mouse xenografts of human CRC cell lines expressing different miR-27a levels confirmed the protein variations and recapitulated the cell growth and apoptosis effects. In vivo miR-27a inversely correlated with MHC class I molecules and calreticulin expression, CD8+ T cells infiltration and cytotoxic activity (LAMP-1 exposure and perforin release). Tumours with high miR-27a, low calreticulin and CD8+ T cells' infiltration were associated with distant metastasis and poor prognosis. Our data demonstrate that miR-27a acts as an oncomiRNA, represses MHC class I expression through calreticulin downregulation and affects tumour progression. These results may pave the way for better diagnosis, patient stratification and novel therapeutic approaches.
cBid, Bax and Bcl-xL exhibit opposite membrane remodeling activities
Authors: Bleicken S , Hofhaus G , Ugarte-Uribe B , Schröder R , García-Sáez A J
Published: February 2016

The proteins of the Bcl-2 family have a crucial role in mitochondrial outer membrane permeabilization during apoptosis and in the regulation of mitochondrial dynamics. Current models consider that Bax forms toroidal pores at mitochondria that are responsible for the release of cytochrome c, whereas Bcl-xL inhibits pore formation. However, how Bcl-2 proteins regulate mitochondrial fission and fusion remains poorly understood. By using a systematic analysis at the single vesicle level, we found that cBid, Bax and Bcl-xL are able to remodel membranes in different ways. cBid and Bax induced a reduction in vesicle size likely related to membrane tethering, budding and fission, besides membrane permeabilization. Moreover, they are preferentially located at highly curved membranes. In contrast, Bcl-xL not only counterbalanced pore formation but also membrane budding and fission. Our findings support a mechanism of action by which cBid and Bax induce or stabilize highly curved membranes including non-lamellar structures. This molecular activity reduces the energy for membrane remodeling, which is a necessary step in toroidal pore formation, as well as membrane fission and fusion, and provides a common mechanism that links the two main functions of Bcl-2 proteins.
In situ stress observation in oxide films and how tensile stress influences oxygen ion conduction
Authors: Fluri Aline , Pergolesi Daniele , Roddatis Vladimir , Wokaun Alexander , Lippert Thomas
Published: February 2016

Many properties of materials can be changed by varying the interatomic distances in the crystal lattice by applying stress. Ideal model systems for investigations are heteroepitaxial thin films where lattice distortions can be induced by the crystallographic mismatch with the substrate. Here we describe an in situ simultaneous diagnostic of growth mode and stress during pulsed laser deposition of oxide thin films. The stress state and evolution up to the relaxation onset are monitored during the growth of oxygen ion conducting Ce0.85Sm0.15O2-δ thin films via optical wafer curvature measurements. Increasing tensile stress lowers the activation energy for charge transport and a thorough characterization of stress and morphology allows quantifying this effect using samples with the conductive properties of single crystals. The combined in situ application of optical deflectometry and electron diffraction provides an invaluable tool for strain engineering in Materials Science to fabricate novel devices with intriguing functionalities.
Photoresponse of supramolecular self-assembled networks on graphene–diamond interfaces
Authors: Wieghold Sarah , Li Juan , Simon Patrick , Krause Maximilian , Avlasevich Yuri , Li Chen , Garrido Jose A. , Heiz Ueli , Samorì Paolo , Müllen Klaus , Esch Friedrich , Barth Johannes V. , Palma Carlos-Andres
Published: February 2016

Nature employs self-assembly to fabricate the most complex molecularly precise machinery known to man. Heteromolecular, two-dimensional self-assembled networks provide a route to spatially organize different building blocks relative to each other, enabling synthetic molecularly precise fabrication. Here we demonstrate optoelectronic function in a near-to-monolayer molecular architecture approaching atomically defined spatial disposition of all components. The active layer consists of a self-assembled terrylene-based dye, forming a bicomponent supramolecular network with melamine. The assembly at the graphene-diamond interface shows an absorption maximum at 740 nm whereby the photoresponse can be measured with a gallium counter electrode. We find photocurrents of 0.5 nA and open-circuit voltages of 270 mV employing 19 mW cm−2 irradiation intensities at 710 nm. With an ex situ calculated contact area of 9.9 × 102 μm2, an incident photon to current efficiency of 0.6% at 710 nm is estimated, opening up intriguing possibilities in bottom-up optoelectronic device fabrication with molecular resolution.
Control of antiferromagnetic domain distribution via polarization-dependent optical annealing
Authors: Higuchi Takuya , Kuwata-Gonokami Makoto
Published: February 2016

The absence of net magnetization inside antiferromagnetic domains has made the control of their spatial distribution quite challenging. Here we experimentally demonstrate an optical method for controlling antiferromagnetic domain distributions in MnF2. Reduced crystalline symmetry can couple an order parameter with non-conjugate external stimuli. In the case of MnF2, time-reversal symmetry is macroscopically broken reflecting the different orientations of the two magnetic sublattices. Thus, it exhibits different absorption coefficients between two orthogonal linear polarizations below its antiferromagnetic transition temperature under an external magnetic field. Illumination with linearly polarized laser light under this condition selectively destructs the formation of a particular antiferromagnetic order via heating. As a result, the other antiferromagnetic order is favoured inside the laser spot, achieving spatially localized selection of an antiferromagnetic order. Applications to control of interface states at antiferromagnetic domain boundaries, exchange bias and control of spin currents are expected.
Magnon spectrum of the helimagnetic insulator Cu2OSeO3
Authors: Portnichenko P. Y. , Romhányi J. , Onykiienko Y. A. , Henschel A. , Schmidt M. , Cameron A. S. , Surmach M. A. , Lim J. A. , Park J. T. , Schneidewind A. , Abernathy D. L. , Rosner H. , van den Brink Jeroen , Inosov D. S.
Published: February 2016

Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases.
Possible observation of highly itinerant quantum magnetic monopoles in the frustrated pyrochlore Yb2Ti2O7
Authors: Tokiwa Y. , Yamashita T. , Udagawa M. , Kittaka S. , Sakakibara T , Terazawa D. , Shimoyama Y. , Terashima T. , Yasui Y. , Shibauchi T. , Matsuda Y.
Published: February 2016

The low-energy elementary excitations in frustrated quantum magnets have fascinated researchers for decades. In frustrated Ising magnets on a pyrochlore lattice possessing macroscopically degenerate spin-ice ground states, the excitations have been discussed in terms of classical magnetic monopoles, which do not contain quantum fluctuations. Here we report unusual behaviours of magneto-thermal conductivity in the disordered spin-liquid regime of pyrochlore Yb2Ti2O7, which hosts frustrated spin-ice correlations with large quantum fluctuations owing to pseudospin-1/2 of Yb ions. The analysis of the temperature and magnetic field dependencies shows the presence of gapped elementary excitations. We find that the gap energy is largely suppressed from that expected in classical monopoles. Moreover, these excitations propagate a long distance without being scattered, in contrast to the diffusive nature of classical monopoles. These results suggests the emergence of highly itinerant quantum magnetic monopole, which is a heavy quasiparticle that propagates coherently in three-dimensional spin liquids.
The Bub1–Plk1 kinase complex promotes spindle checkpoint signalling through Cdc20 phosphorylation
Authors: Jia Luying , Li Bing , Yu Hongtao
Published: February 2016

The spindle checkpoint senses unattached kinetochores and inhibits the Cdc20-bound anaphase-promoting complex or cyclosome (APC/C), to delay anaphase, thereby preventing aneuploidy. A critical checkpoint inhibitor of APC/CCdc20 is the mitotic checkpoint complex (MCC). It is unclear whether MCC suffices to inhibit all cellular APC/C. Here we show that human checkpoint kinase Bub1 not only directly phosphorylates Cdc20, but also scaffolds Plk1-mediated phosphorylation of Cdc20. Phosphorylation of Cdc20 by Bub1–Plk1 inhibits APC/CCdc20in vitro and is required for checkpoint signalling in human cells. Bub1–Plk1-dependent Cdc20 phosphorylation is regulated by upstream checkpoint signals and is dispensable for MCC assembly. A phospho-mimicking Cdc20 mutant restores nocodazole-induced mitotic arrest in cells depleted of Mad2 or BubR1. Thus, Bub1–Plk1-mediated phosphorylation of Cdc20 constitutes an APC/C-inhibitory mechanism that is parallel, but not redundant, to MCC formation. Both mechanisms are required to sustain mitotic arrest in response to spindle defects.
Novel loci and pathways significantly associated with longevity
Authors: Zeng Yi , Nie Chao , Min Junxia , Liu Xiaomin , Li Mengmeng , Chen Huashuai , Xu Hanshi , Wang Mingbang , Ni Ting , Li Yang , Yan Han , Zhang Jin-Pei , Song Chun , Chi Li-Qing , Wang Han-Ming , Dong Jie , Zheng Gu-Yan , Lin Li , Qian Feng , Qi Yanwei , Liu Xiao , Cao Hongzhi , Wang Yinghao , Zhang Lijuan , Li Zhaochun , Zhou Yufeng , Wang Yan , Lu Jiehua , Li Jianxin , Qi Ming , Bolund Lars , Yashin Anatoliy , Land Kenneth C. , Gregory Simon , Yang Ze , Gottschalk William , Tao Wei , Wang Jian , Wang Jun , Xu Xun , Bae Harold , Nygaard Marianne , Christiansen Lene , Christensen Kaare , Franceschi Claudio , Lutz Michael W. , Gu Jun , Tan Qihua , Perls Thomas , Sebastiani Paola , Deelen Joris , Slagboom Eline , Hauser Elizabeth , Xu Huji , Tian Xiao-Li , Yang Huanming , Vaupel James W.
Published: February 2016

Only two genome-wide significant loci associated with longevity have been identified so far, probably because of insufficient sample sizes of centenarians, whose genomes may harbor genetic variants associated with health and longevity. Here we report a genome-wide association study (GWAS) of Han Chinese with a sample size 2.7 times the largest previously published GWAS on centenarians. We identified 11 independent loci associated with longevity replicated in Southern-Northern regions of China, including two novel loci (rs2069837-IL6; rs2440012-ANKRD20A9P) with genome-wide significance and the rest with suggestive significance (P < 3.65 × 10−5). Eight independent SNPs overlapped across Han Chinese, European and U.S. populations, and APOE and 5q33.3 were replicated as longevity loci. Integrated analysis indicates four pathways (starch, sucrose and xenobiotic metabolism; immune response and inflammation; MAPK; calcium signaling) highly associated with longevity (P ≤ 0.006) in Han Chinese. The association with longevity of three of these four pathways (MAPK; immunity; calcium signaling) is supported by findings in other human cohorts. Our novel finding on the association of starch, sucrose and xenobiotic metabolism pathway with longevity is consistent with the previous results from Drosophilia. This study suggests protective mechanisms including immunity and nutrient metabolism and their interactions with environmental stress play key roles in human longevity.
Bacterial cellulose synthesis mechanism of facultative anaerobe Enterobacter sp. FY-07
Authors: Ji Kaihua , Wang Wei , Zeng Bing , Chen Sibin , Zhao Qianqian , Chen Yueqing , Li Guoqiang , Ma Ting
Published: February 2016

Enterobacter sp. FY-07 can produce bacterial cellulose (BC) under aerobic and anaerobic conditions. Three potential BC synthesis gene clusters (bcsI, bcsII and bcsIII) of Enterobacter sp. FY-07 have been predicted using genome sequencing and comparative genome analysis, in which bcsIII was confirmed as the main contributor to BC synthesis by gene knockout and functional reconstitution methods. Protein homology, gene arrangement and gene constitution analysis indicated that bcsIII had high identity to the bcsI operon of Enterobacter sp. 638; however, its arrangement and composition were same as those of BC synthesizing operon of G. xylinum ATCC53582 except for the flanking sequences. According to the BC biosynthesizing process, oxygen is not directly involved in the reactions of BC synthesis, however, energy is required to activate intermediate metabolites and synthesize the activator, c-di-GMP. Comparative transcriptome and metabolite quantitative analysis demonstrated that under anaerobic conditions genes involved in the TCA cycle were downregulated, however, genes in the nitrate reduction and gluconeogenesis pathways were upregulated, especially, genes in three pyruvate metabolism pathways. These results suggested that Enterobacter sp. FY-07 could produce energy efficiently under anaerobic conditions to meet the requirement of BC biosynthesis.
Engineering hybrid exosomes by membrane fusion with liposomes
Authors: Sato Yuko T. , Umezaki Kaori , Sawada Shinichi , Mukai Sada-atsu , Sasaki Yoshihiro , Harada Naozumi , Shiku Hiroshi , Akiyoshi Kazunari
Published: February 2016

Exosomes are a valuable biomaterial for the development of novel nanocarriers as functionally advanced drug delivery systems. To control and modify the performance of exosomal nanocarriers, we developed hybrid exosomes by fusing their membranes with liposomes using the freeze–thaw method. Exosomes embedded with a specific membrane protein isolated from genetically modified cells were fused with various liposomes, confirming that membrane engineering methods can be combined with genetic modification techniques. Cellular uptake studies performed using the hybrid exosomes revealed that the interactions between the developed exosomes and cells could be modified by changing the lipid composition or the properties of the exogenous lipids. These results suggest that the membrane-engineering approach reported here offers a new strategy for developing rationally designed exosomes as hybrid nanocarriers for use in advanced drug delivery systems.
Macrophage-derived Lipocalin-2 contributes to ischemic resistance mechanisms by protecting from renal injury
Authors: Jung Michaela , Brüne Bernhard , Hotter Georgina , Sola Anna
Published: February 2016

Renal ischemia-reperfusion injury triggers an inflammatory response associated to infiltrating macrophages which determines the further outcome of disease. Brown Norway rats are known to show endogenous resistance to ischemia-induced renal damage. By contrast, Sprague Dawley rats exhibit a higher susceptibility to ischemic injury. In order to ascertain cytoprotective mechanisms, we focused on the implication of lipocalin-2 protein in main resistance mechanisms in renal ischemia/reperfusion injury by using adoptive macrophage administration, genetically modified ex vivo either to overexpress or to knockdown lipocalin-2. In vitro experiments with bone marrow-derived macrophages both from Brown Norway rats and from Sprague Dawley rats under hypoxic conditions showed endogenous differences regarding cytokine and lipocalin-2 expression profile in the two strains. Most interestingly, we observed that macrophages of the resistant strain express significantly more lipocalin-2. In vivo studies showed that tubular epithelial cell apoptosis and renal injury significantly increased and reparative markers decreased in Brown Norway rats after injection of lipocalin-2-knockdown macrophages, while the administration of lipocalin-2-overexpressing cells significantly decreased Sprague Dawley susceptibility. These data point to a crucial role of macrophage-derived lipocalin-2 in endogenous cytoprotective mechanisms. We conclude that expression of lipocalin-2 in tissue-infiltrating macrophages is pivotal for kidney-intrinsic cytoprotective pathways during ischemia reperfusion injury.
Loss of CEACAM1, a Tumor-Associated Factor, Attenuates Post-infarction Cardiac Remodeling by Inhibiting Apoptosis
Authors: Wang Yan , Chen Yanmei , Yan Yi , Li Xinzhong , Chen Guojun , He Nvqin , Shen Shuxin , Chen Gangbin , Zhang Chuanxi , Liao Wangjun , Liao Yulin , Bin Jianping
Published: February 2016

Carcinoembryonic antigen-related cell adhesion molecule1 (CEACAM1) is a tumor-associated factor that is known to be involved in apoptosis, but the role of CEACAM1 in cardiovascular disease is unclear. We aims to investigate whether CEACAM1 influences cardiac remodeling in mice with myocardial infarction (MI) and hypoxia-induced cardiomyocyte injury. Both serum in patients and myocardial CEACAM1 levels in mice were significantly increased in response to MI, while levels were elevated in neonatal rat cardiomyocytes (NRCs) exposed to hypoxia. Eight weeks after MI, a lower mortality rate, improved cardiac function and less cardiac remodeling in CEACAM1 knock-out (KO) mice than in their wild-type (WT) littermates were observed. Moreover, myocardial expression of mitochondrial Bax, cytosolic cytochrome C and cleaved caspase-3 was significantly lower in CEACAM1 KO mice than in WT mice. In cultured NRCs exposed to hypoxia, recombinant human CEACAM1 (rhCEACAM1) reduced mitochondrial membrane potential, upregulated mitochondrial Bax, increased cytosolic cytochrome C and cleaved caspase-3 and consequently increased apoptosis. RhCEACAM1 also increased the levels of GRP78 and CHOP in NRCs with hypoxia. All of these effects were abolished by silencing CEACAM1. Our study indicates that CEACAM1 exacerbates hypoxic cardiomyocyte injury and post-infarction cardiac remodeling by enhancing cardiomyocyte mitochondrial dysfunction and endoplasmic reticulum stress-induced apoptosis.
Spatial and temporal evolution of Lassa virus in the natural host population in Upper Guinea
Authors: Fichet-Calvet Elisabeth , Ölschläger Stephan , Strecker Thomas , Koivogui Lamine , Becker-Ziaja Beate , Camara Amara Bongo , Soropogui Barré , Magassouba N’Faly , Günther Stephan
Published: February 2016

This study aimed at reconstructing the spatial and temporal evolution of Lassa virus (LASV) in the natural host population. To this end, we generated 132 partial nucleoprotein sequences of LASV from M. natalensis trapped in 12 villages around Faranah, Upper Guinea, over a period of 12 years. This study reveals two main features of LASV evolution in M. natalensis. First, the virus evolves in the reservoir with a molecular clock rate of 9 (7–11) × 10–4 position–1 year–1 implying that contemporary LASV lineages circulate in the Faranah area since less than 100 years. Second, viruses circulating in a specific village are diverse and polyphyletic. We observed, however, there are monophyletic clusters at village and sub-village level at specific points in time. In conclusion, our data indicate that the temporal and spatial pattern of LASV evolution in the natural reservoir is characterized by a combination of stationary circulation within a village and virus movement between villages. The latter feature is relevant for rodent control strategies, as it implies that recurrence of the virus from neighbouring villages may occur in villages where the virus has previously been eradicated.
Increased Aβ pathology in aged Tg2576 mice born to mothers fed a high fat diet
Authors: Nizari Shereen , Carare Roxana O. , Hawkes Cheryl A.
Published: February 2016

Maternal obesity is associated with increased risk of developing diabetes, obesity and premature death in adult offspring. Mid-life diabetes, hypertension and hypercholesterolaemia are risk factors for the development of sporadic Alzheimer’s disease (AD). A key pathogenic feature of AD is the accumulation of β-amyloid (Aβ) in the brain. The purpose of this study was to investigate the effect of high fat diet feeding during early life on Aβ pathology in the Tg2576 mouse model of AD. Female mice were fed a standard (C) or high fat (HF) diet before mating and during gestation and lactation. At weaning, male offspring were fed a C diet. Significantly higher levels of guanidine-soluble Aβ and plaque loads were observed in the hippocampi of 11-month old Tg2576 mice born to mothers fed a HF diet. Changes in the extracellular matrix led to increased retention of Aβ within the parenchyma. These data support a role for maternal and gestational health on the health of the aged brain and pathologies associated with AD and may provide a novel target for both the prevention and treatment of AD.
Simultaneous retrieval of temperature-dependent absorption coefficient and conductivity of participating media
Authors: Ren Yatao , Qi Hong , Zhao Fangzhou , Ruan Liming , Tan Heping
Published: February 2016

A secondary optimization technique was proposed to estimate the temperature-dependent thermal conductivity and absorption coefficient. In the proposed method, the stochastic particle swarm optimization was applied to solve the inverse problem. The coupled radiation and conduction problem was solved in a 1D absorbing, emitting, but non-scattering slab exposed to a pulse laser. It is found that in the coupled radiation and conduction problem, the temperature response is highly sensitive to conductivity but slightly sensitive to the optical properties. On the contrary, the radiative intensity is highly sensitive to optical properties but slightly sensitive to thermal conductivity. Therefore, the optical and thermal signals should both be considered in the inverse problem to estimate the temperature-dependent properties of the transparent media. On this basis, the temperature-dependent thermal conductivity and absorption coefficient were both estimated accurately by measuring the time-dependent temperature, and radiative response at the boundary of the slab.
III–V compound semiconductors for mass-produced nano-electronics: theoretical studies on mobility degradation by dislocation
Authors: Hur Ji-Hyun , Jeon Sanghun
Published: February 2016

As silicon-based electronics approach the limit of scaling for increasing the performance and chip density, III–V compound semiconductors have started to attract significant attention owing to their high carrier mobility. However, the mobility benefits of III–V compounds are too easily accepted, ignoring a harmful effect of unavoidable threading dislocations that could fundamentally limit the applicability of these materials in nanometer-scale electronics. In this paper, we present a theoretical model that describes the degradation of carrier mobility by charged dislocations in quantum-confined III–V semiconductor metal oxide field effect transistors (MOSFETs). Based on the results, we conclude that in order for III–V compound MOSFETs to outperform silicon MOSFETs, Fermi level pinning in the channel should be eliminated for yielding carriers with high injection velocity.
Complete nondestructive analysis of two-photon six-qubit hyperentangled Bell states assisted by cross-Kerr nonlinearity
Authors: Liu Qian , Wang Guan-Yu , Ai Qing , Zhang Mei , Deng Fu-Guo
Published: February 2016

Hyperentanglement, the entanglement in several degrees of freedom (DOFs) of a quantum system, has attracted much attention as it can be used to increase both the channel capacity of quantum communication and its security largely. Here, we present the first scheme to completely distinguish the hyperentangled Bell states of two-photon systems in three DOFs with the help of cross-Kerr nonlinearity without destruction, including two longitudinal momentum DOFs and the polarization DOF. We use cross-Kerr nonlinearity to construct quantum nondemolition detectors which can be used to make a parity-check measurement and analyze Bell states of two-photon systems in different DOFs. Our complete scheme for two-photon six-qubit hyperentangled Bell-state analysis may be useful for the practical applications in quantum information, especially in long-distance high-capacity quantum communication.
Wide-field optical coherence tomography based microangiography for retinal imaging
Authors: Zhang Qinqin , Lee Cecilia S. , Chao Jennifer , Chen Chieh-Li , Zhang Thomas , Sharma Utkarsh , Zhang Anqi , Liu Jin , Rezaei Kasra , Pepple Kathryn L. , Munsen Richard , Kinyoun James , Johnstone Murray , Van Gelder Russell N. , Wang Ruikang K.
Published: February 2016

Optical coherence tomography angiography (OCTA) allows for the evaluation of functional retinal vascular networks without a need for contrast dyes. For sophisticated monitoring and diagnosis of retinal diseases, OCTA capable of providing wide-field and high definition images of retinal vasculature in a single image is desirable. We report OCTA with motion tracking through an auxiliary real-time line scan ophthalmoscope that is clinically feasible to image functional retinal vasculature in patients, with a coverage of more than 60 degrees of retina while still maintaining high definition and resolution. We demonstrate six illustrative cases with unprecedented details of vascular involvement in retinal diseases. In each case, OCTA yields images of the normal and diseased microvasculature at all levels of the retina, with higher resolution than observed with fluorescein angiography. Wide-field OCTA technology will be an important next step in augmenting the utility of OCT technology in clinical practice.
Size-selective separation of DNA fragments by using lysine-functionalized silica particles
Authors: Liu Lingling , Guo Zilong , Huang Zhenzhen , Zhuang Jiaqi , Yang Wensheng
Published: February 2016

In this work, a facile and efficient approach has been demonstrated for size-selective separation of DNA fragments by using lysine-functionalized silica particles. At a given pH, the environmental ionic strength can be utilized to alter the electrostatic interactions of lysine-functionalized silica particles with DNA fragments and in turn the DNA fragments on the silica particle surfaces, which exhibits a clear dependence on the DNA fragment sizes. By carefully adjusting the environmental pH and salt concentration, therefore, the use of the lysine-functionalized silica particles allows effective separation of binary and ternary DNA mixtures, for example, two different DNA fragments with sizes of 101 and 1073 bp, 101 and 745 bp, 101 and 408 bp, respectively and three different DNA fragments with sizes of 101, 408 and 1073 bp.
Two-walker discrete-time quantum walks on the line with percolation
Authors: Rigovacca L. , Di Franco C.
Published: February 2016

One goal in the quantum-walk research is the exploitation of the intrinsic quantum nature of multiple walkers, in order to achieve the full computational power of the model. Here we study the behaviour of two non-interacting particles performing a quantum walk on the line when the possibility of lattice imperfections, in the form of missing links, is considered. We investigate two regimes, statical and dynamical percolation, that correspond to different time scales for the imperfections evolution with respect to the quantum-walk one. By studying the qualitative behaviour of three two-particle quantities for different probabilities of having missing bonds, we argue that the chosen symmetry under particle-exchange of the input state strongly affects the output of the walk, even in noisy and highly non-ideal regimes. We provide evidence against the possibility of gathering information about the walkers indistinguishability from the observation of bunching phenomena in the output distribution, in all those situations that require a comparison between averaged quantities. Although the spread of the walk is not substantially changed by the addition of a second particle, we show that the presence of multiple walkers can be beneficial for a procedure to estimate the probability of having a broken link.
Rational design and validation of an anti-protein kinase C active-state specific antibody based on conformational changes
Authors: Pena Darlene Aparecida , Andrade Victor Piana de , Silva Gabriela Ávila Fernandes , Neves José Ivanildo , Oliveira Paulo Sergio Lopes de , Alves Maria Julia Manso , Devi Lakshmi A. , Schechtman Deborah
Published: February 2016

Protein kinase C (PKC) plays a regulatory role in key pathways in cancer. However, since phosphorylation is a step for classical PKC (cPKC) maturation and does not correlate with activation, there is a lack of tools to detect active PKC in tissue samples. Here, a structure-based rational approach was used to select a peptide to generate an antibody that distinguishes active from inactive cPKC. A peptide conserved in all cPKCs, C2Cat, was chosen since modeling studies based on a crystal structure of PKCβ showed that it is localized at the interface between the C2 and catalytic domains of cPKCs in an inactive kinase. Anti-C2Cat recognizes active cPKCs at least two-fold better than inactive kinase in ELISA and immunoprecipitation assays and detects the temporal dynamics of cPKC activation upon receptor or phorbol stimulation. Furthermore, the antibody is able to detect active PKC in human tissue. Higher levels of active cPKC were observed in the more aggressive triple negative breast cancer tumors as compared to the less aggressive estrogen receptor positive tumors. Thus, this antibody represents a reliable, hitherto unavailable and a valuable tool to study PKC activation in cells and tissues. Similar structure-based rational design strategies can be broadly applied to obtain active-state specific antibodies for other signal transduction molecules.
Differential Proteomic Analysis of Human Saliva using Tandem Mass Tags Quantification for Gastric Cancer Detection
Authors: Xiao Hua , Zhang Yan , Kim Yong , Kim Sung , Kim Jae Joon , Kim Kyoung Mee , Yoshizawa Janice , Fan Liu-Yin , Cao Cheng-Xi , Wong David T. W.
Published: February 2016

Novel biomarkers and non-invasive diagnostic methods are urgently needed for the screening of gastric cancer to reduce its high mortality. We employed quantitative proteomics approach to develop discriminatory biomarker signatures from human saliva for the detection of gastric cancer. Salivary proteins were analyzed and compared between gastric cancer patients and matched control subjects by using tandem mass tags (TMT) technology. More than 500 proteins were identified with quantification, and 48 of them showed significant difference expression (p < 0.05) between normal controls and gastric cancer patients, including 7 up-regulated proteins and 41 down-regulated proteins. Five proteins were selected for initial verification by ELISA and three were successfully verified, namely cystatin B (CSTB), triosephosphate isomerase (TPI1), and deleted in malignant brain tumors 1 protein (DMBT1). All three proteins could differentiate gastric cancer patients from normal control subjects, dramatically (p < 0.05). The combination of these three biomarkers could reach 85% sensitivity and 80% specificity for the detection of gastric cancer with accuracy of 0.93. This study provides the proof of concept of salivary biomarkers for the non-invasive detection of gastric cancer. It is highly encouraging to turn these biomarkers into an applicable clinical test after large scale validation.
Neutron activation analysis for cement elements using an IECF device as a high energy neutron source
Authors: Zadeh E. Eftekhari , Sadighzadeh A. , Salehizadeh A. , Nazemi E. , Roshani G. H.
Published: February 2016

In this study, Neutron Activation Analysis (NAA) for cement elements using an Inertial Electrostatic Confinement Fusion (IECF) facility as a high energy neutron source is investigated.
A fluorescent surrogate of thymidine in duplex DNA
Authors: Mata Guillaume , Schmidt Olivia P. , Luedtke Nathan W.
Published: February 2016

DMAT is a new fluorescent thymidine mimic composed of 2′-deoxyuridine fused to dimethylaniline.
Oxygen isotope exchange in La2NiO4±δ
Authors: Ananyev M. V. , Tropin E. S. , Eremin V. A. , Farlenkov A. S. , Smirnov A. S. , Kolchugin A. A. , Porotnikova N. M. , Khodimchuk A. V. , Berenov A. V. , Kurumchin E. Kh.
Published: February 2016

Oxygen surface exchange kinetics and diffusion have been studied by the isotope exchange method with gas phase equilibration using a static circulation experimental rig in the temperature range of 600–800 °C and oxygen pressure range of 0.13–2.5 kPa.
Universal statistical fluctuations in thermodynamics and kinetics of single molecular recognition
Authors: Zheng Xiliang , Wang Jin
Published: February 2016

We investigated the main universal statistical distributions of single molecular recognition.
[RuCl2(η6-p-cymene)] complexes bearing phosphinous acid ligands: preparation, application in C–H bond functionalization and mechanistic investigations
Authors: Graux Lionel V. , Giorgi Michel , Buono Gérard , Clavier Hervé
Published: February 2016

A series of [RuCl2(η6-p-cymene)] complexes bearing phosphinous acid (PA) ligands have been straightforwardly prepared from the dimer [RuCl2(p-cymene)]2and secondary phosphine oxides (SPOs) and fully characterized.
The morphology-controlled synthesis of a nanoporous-antimony anode for high-performance sodium-ion batteries
Authors: Liu Shuai , Feng Jinkui , Bian Xiufang , Liu Jie , Xu Hui
Published: February 2016

We propose a novel, practical way to prepare nanoporous Sb with different morphologies and Sb particles of varying size through chemical dealloying of Al–Sb alloy ribbon precursors with different compositions, a top-down process.
In situ synthesis and photocatalytic performance of WO3/ZnWO4 composite powders
Authors: Li Wen , Cao Liyun , Kong Xingang , Huang Jianfeng , Yao Chunyan , Fei Jie , Li Jiayin
Published: February 2016

The WO3/ZnWO4 composite powders were synthesized through an in situ reaction process with tunnel structure K10W12O41·11H2O filiform crystallites used as a precursor.
Band engineering of perovskite-type transition metal oxynitrides for photocatalytic overall water splitting
Authors: Pan Chengsi , Takata Tsuyoshi , Kumamoto Kazunori , Khine Ma Su Su , Ueda Koichiro , Minegishi Tsutomu , Nakabayashi Mamiko , Matsumoto Takao , Shibata Naoya , Ikuhara Yuichi , Domen Kazunari
Published: February 2016

In LaMxTa1−xO1+(5−n)xN2−(5−n)x (Mn+ = Mg2+, Sc3+, and Zr4+) solid solutions, increasing the Mn+ (n = 2 and 3) content tuned the bandgap position, which facilitated water oxidation as well as overall water splitting.
Manipulating three-dimensional gel network entanglement by thin film shearing
Authors: Kumari Harshita , Kline Steven R. , Kennedy Stuart R. , Garvey Christopher , Raston Colin L. , Atwood Jerry L. , Steed Jonathan W.
Published: February 2016

A novel method of combining thin-film shearing with SANS resulted in complete disruption of 3-D network of fluorous bis-urea gel. In contrast, non-fluorinated analogue undergoes partial disruption which emphasizes the resistance of non-fluorous bis-urea gelators towards shear.
Long-chain NHC-stabilized RuNPs as versatile catalysts for one-pot oxidation/hydrogenation reactions
Authors: Martínez-Prieto L. M. , Ferry A. , Rakers L. , Richter C. , Lecante P. , Philippot K. , Chaudret B. , Glorius F.
Published: February 2016

The synthesis and catalytic activity of long-chain NHC-stabilized RuNPs are presented.
The structural diversity and properties of nine new viologen based zwitterionic metal–organic frameworks
Authors: Aulakh Darpandeep , Nicoletta Anthony P. , Varghese Juby R. , Wriedt Mario
Published: February 2016

A viologen based ligand has been explored as a functional building block to synthesize a series of nine new zwitterionic metal–organic frameworks with this contribution reporting on their structural, thermal and photochromic properties.
New mechanistic insight into the oxygen reduction reaction on Ruddlesden–Popper cathodes for intermediate-temperature solid oxide fuel cells
Authors: Li Wenyuan , Guan Bo , Zhang Xinxin , Yan Jianhua , Zhou Yue , Liu Xingbo
Published: February 2016

Ruddlesden–Popper (R–P) phase materials have been investigated widely as cathode candidates for IT-SOFCs.
Strategies for modulating the luminescence properties of pyronin Y dye–clay films: an experimental and theoretical study
Authors: Epelde-Elezcano Nerea , Martínez-Martínez Virginia , Duque-Redondo Eduardo , Temiño Inés , Manzano Hegoi , López-Arbeloa Iñigo
Published: February 2016

The aggregation process of pyronin Y (PY) dye into thin films of different smectite clays, LAPONITE® and saponite, is deeply studied by means of electronic absorption and fluorescence spectroscopy and by molecular dynamics simulations.
Coordination and supramolecular assembly of {Cd2Ge8V12O48} building block and cucurbit[6] to form rotaxane-shaped hybrids
Authors: Wei Mei-Jie , Zang Hong-Ying , Zhou En-Long , Shao Kui-Zhan , Song Bai-Qiao , Wang Xin-Long , Su Zhong-Min
Published: February 2016

Assembly of cucurbit[6] and {Cd2Ge8V12O48} cluster produced two rotaxane-shaped and polyrotaxane-shaped solids. High oxygen density of polyoxoanion surface provides active sites to extend a single rotaxane-shaped hybrid 1 to a 1D polyrotaxane-shaped hybrid 2.
A systematic molecular dynamics approach to the study of peptide Keap1–Nrf2 protein–protein interaction inhibitors and its application to p62 peptides
Authors: Lu Meng-Chen , Yuan Zhen-Wei , Jiang Yong-Lin , Chen Zhi-Yun , You Qi-Dong , Jiang Zheng-Yu
Published: February 2016

Protein–protein interactions (PPIs) as drug targets have been gaining growing interest, though developing drug-like small molecule PPI inhibitors remains challenging.
A single terpene synthase is responsible for a wide variety of sesquiterpenes in Sorangium cellulosum Soce56
Authors: Schifrin Alexander , Khatri Yogan , Kirsch Philine , Thiel Verena , Schulz Stefan , Bernhardt Rita
Published: February 2016

The myxobacterium Sorangium cellulosum So ce56 is a prolific producer of volatile sesquiterpenes.
A family of polypropylene glycol-grafted polyethyleneimines reversibly absorb and release carbon dioxide to blow polyurethanes
Authors: Long Yuanzhu , Sun Fuhua , Liu Chao , Xie Xingyi
Published: February 2016

The chemical structure of CO2adducts from polypropylene glycol grafted polyethyleneimines has been optimised to blow polyurethanes.
A graphene oxide layer as an acid-resisting barrier deposited on a zeolite LTA membrane for dehydration of acetic acid
Authors: Xu Kai , Jiang Zhenqi , Feng Bo , Huang Aisheng
Published: February 2016

A graphene oxide layer (GO) was deposited as acid-resisting barrier to avoid the degradation of zeolite LTA membrane by acetic acid, leading to a high selectivity and stability of the zeolite LTA membrane for the dehydration of acetic acid.
New transparent poly(l-lactide acid) films as high-performance bio-based nanocomposites
Authors: Cheng Chih-Chia , Liao Hao-Wen , Chen Jem-Kun , Lee Duu-Jong , Xin Zhong
Published: February 2016

A new tri-POSS-end-capped poly(lactic acid) bio-nanocomposite forms transparent films with significantly enhanced gas barrier properties and improved mechanical performance.
Intrinsic charge carrier dynamics and device stability of perovskite/ZnO mesostructured solar cells in moisture
Authors: Lei Yan , Gu Longyan , He Weiwei , Jia Zuxiao , Yang Xiaogang , Jia Huimin , Zheng Zhi
Published: February 2016

High quality CH3NH3PbI3/PbI2/ZnO p–i–n junction solar cells fabricated in moisture maintained more than 72% of their initial PCE after 250 days storage.
Analogue/RF performance attributes of underlap tunnel field effect transistor for low power applications
Authors: Vijayvargiya V. , Reniwal B.S. , Singh P. , Vishvakarma S.K.
Published: February 2016

Tunnel field effect transistor (TFET) is being considered as an alternative to the conventional MOSFETs for low power system on chip applications. In this Letter, gate‐drain underlap (UL) feature of double gate TFET for analogue/RF characteristic is discussed. Here, it is found that parasitic resistance induced by gate drain UL is not significant as compared with DG tunnel field effect transistor (DG‐FET). Thus, the behaviour of RF figure of merit is different from DG‐FET.
Technical noise in K‐band low‐noise cryogenic amplifier
Authors: Parker S.R.
Published: February 2016

The performance of a 15–29 GHz low‐noise high‐electron‐mobility transistor amplifier at room and cryogenic temperatures is reported. The close‐to‐carrier technical noise is measured for frequency offsets from 100 mHz to 100 kHz and the effect of adjusting the DC power biasing is investigated. An order of magnitude improvement in intrinsic phase noise is achieved by optimising the bias settings away from manufacturer specifications, giving a single‐sideband phase noise power spectral density at 1 Hz offset of −100 dBc/Hz and −105 dBc/Hz for a 26.6 GHz carrier at room temperature and 6.5 K, respectively.
Circular beam‐reconfigurable antenna base on graphene‐metal hybrid
Authors: Cheng Xiaohe , Yao Yuan , Qu Shi‐Wei , Wu Yongle , Yu Junsheng , Chen Xiaodong
Published: February 2016

The concept and analysis of a graphene‐metal beam‐reconfigurable terahertz (THz) loop antenna are presented. The hybrid graphene‐metal implementation is proposed to combine (i) dynamic surface conductivity tunability using different DC bias voltages and (ii) high radiation efficiency enabled by metal. The loop antenna which employs an artificial mu‐negative transmission line provides the horizontally polarised omnidirectional radiation. The graphene‐metal loop around the centre ring acts as a reflector. Changing the DC bias of different position of graphene to control the position of resonance can effectively adjust the beam direction. The proposed concept and achieved performance, computed using realistic material parameters, are extremely promising for beam scanning at THz frequencies.
Iterative learning control for linear discrete‐time systems with high relative degree under initial state vibration
Authors: Wei Yun‐Shan , Li Xiao‐Dong
Published: February 2016

For linear discrete‐time multiple‐input–multiple‐output (MIMO) systems with high relative degree, this study presents three average operator‐based iterative learning control (ILC) algorithms to investigate the effect of initial state vibration on ILC tracking error. The proposed ILC laws include an initial rectifying action against initial state vibration at certain time points, and pursue the reference trajectory tracking beyond the initial time points. It is proved that, when the proposed ILC laws are applied to linear discrete‐time MIMO systems with high relative degree, the effect of the initial state vibration on ILC tracking error beyond the initial time points can be exactly decided. Moreover, the ILC tracking error beyond the initial time points can be driven to zero against a progressive fixed initial state error. Numerical examples are used to illustrate the effectiveness of the proposed ILC laws.
Complex non‐linear phenomena and stability analysis of interconnected power converters used in distributed power systems
Authors: El Aroudi Abdelali , Giaouris Damian , Mandal Kuntal , Banerjee Soumitro , Al‐Hindawi Mohammed , Abusorrah Abdullah , Al‐Turki Yusuf
Published: February 2016

Distributed power systems are considered to be a key element of future power grids. Their main characteristic is the local production and consumption of energy that is accomplished using a number of power converters that interconnect local sources and loads. In this paper, a current mode controlled dc–dc converter which feeds another current mode controlled dc–dc converter is considered to meet the demands of the load. It shows that the existence of the second converter at the output has destabilising effect on the overall system. Such a system may also exhibit interactions of various types of instability that conventional modeling methods cannot predict. Slow‐timescale oscillation in standalone switching converters is usually attributed to the occurrence of a Neimark–Sacker bifurcation of the fundamental periodic orbit of the discrete‐time model of the system. But in the studied cascaded system, the underlying mechanism is quite different. This paper fully explains the mechanisms as well as the conditions of the occurrence of such instabilities by employing the analytical and numerical tools of the exact switched model of the system. These results can be useful for developing design guidelines to avoid such problems. Finally, the results have been validated experimentally.
Multifrequency approximation and average modelling of an isolated bidirectional dc–dc converter for dc microgrids
Authors: Huang Jun , Wang Yue , Li Zhuoqiang , Lei Wanjun
Published: February 2016

This study presents a generalised analysis of isolated bidirectional dual active bridge (DAB) dc–dc converter with triple‐phase‐shift (TPS) control. The multifrequency approximation is used to analyse performance characteristics of DAB, and a novel numerical solver is developed to determine the optimised modulation scheme based on TPS control. Specially, the proposed solver can be considered as a unified solver for determining the optimised operation of DAB with required transmission power and voltage conversion ratio. The multifrequency average model of DAB is then described in this study. A universal control‐to‐output‐voltage transfer function is derived for DAB with any modulation scheme, and the closed‐loop operation is discussed based on the proposed average model. Finally, a laboratory prototype is implemented and experimental results verify the theoretical analysis.