bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct-Writing of Cu Nano-Patterns with an Electron Beam
Authors: Lai Shih-En , Hong Ying-Jhan , Chen Yu-Ting , Kang Yu-Ting , Chang Pin , Yew Tri-Rung 
Published: September 2015

AbstractWe demonstrate direct electron beam writing of a nano-scale Cu pattern on a surface with a thin aqueous layer of CuSO4 solution. Electron beams are highly maneuverable down to nano-scales. Aqueous solutions facilitate a plentiful metal ion supply for practical industrial applications, which may require continued reliable writing of sophisticated patterns. A thin aqueous layer on a surface helps to confine the writing on the surface. For this demonstration, liquid sample holder (K-kit) for transmission electron microscope (TEM) was employed to form a sealed space in a TEM. The aqueous CuSO4 solution inside the sample holder was allowed to partially dry until a uniform thin layer was left on the surface. The electron beam thus reduced Cu ions in the solution to form the desired patterns. Furthermore, the influence of e-beam exposure time and CuSO4(aq) concentration on the Cu reduction was studied in this work. Two growth stages of Cu were shown in the plot of Cu thickness versus e-beam exposure time. The measured Cu reduction rate was found to be proportional to the CuSO4(aq) concentration.
Speckle Suppression by Decoherence in Fluctuation Electron Microscopy
Authors: Rezikyan Aram , Jibben Zechariah J. , Rock Bryan A. , Zhao Gongpu , Koeck Franz A.M. , Nemanich Robert F. , Treacy Michael M.J. 
Published: September 2015

AbstractWe compare experimental fluctuation electron microscopy (FEM) speckle data with electron diffraction simulations for thin amorphous carbon and silicon samples. We find that the experimental speckle intensity variance is generally more than an order of magnitude lower than kinematical scattering theory predicts for spatially coherent illumination.We hypothesize that decoherence, which randomizes the phase relationship between scattered waves, is responsible for the anomaly. Specifically,displacement decoherencecan contribute strongly to speckle suppression, particularly at higher beam energies. Displacement decoherence arises when the local structure is rearranged significantly by interactions with the beam during the exposure. Such motions cause diffraction speckle to twinkle, some of it at observable time scales.We also find that the continuous random network model of amorphous silicon can explain the experimental variance data if displacement decoherence and multiple scattering is included in the modeling. This may resolve the longstanding discrepancy between X-ray and electron diffraction studies of radial distribution functions, and conclusions reached from previous FEM studies.Decoherence likely affects all quantitative electron imaging and diffraction studies. It likely contributes to the so-called Stobbs factor, where high-resolution atomic-column image intensities are anomalously lower than predicted by a similar factor to that observed here.
Examining self-verification processes in social anxiety
Authors: Howarth Mitchell P. A. , Forbes Miriam 
Published: September 2015

AbstractSocially anxious individuals hold negative beliefs about their appearance, abilities and personality. These negative self-conceptions increase expectations of negative evaluation from others and, consequently increase anxiety. Self-verification theory states that individuals seek, accept and prefer feedback that is congruent with their self-conceptions. This study explored the assumptions of self-verification theory in social anxiety. This was achieved by examining the type of feedback socially anxious individuals seek and how positive and negative feedback is processed. Results from an undergraduate sample (n = 84) indicate that socially anxious individuals were no more or less likely to seek negative feedback than individuals with low social anxiety. However, participants with greater social anxiety rated positive feedback as less accurate, rated negative feedback as more accurate, and were more comfortable with negative feedback, compared to participants with low social anxiety. Greater social anxiety was also found to predict increased discomfort with positive feedback, and fear of negative evaluation fully mediated this relationship. These findings suggest that self-verification processes operate in social anxiety and highlight the need for researchers to include measures of fears of evaluation when examining self-verification theory in samples of socially anxious individuals.
Dynamical backaction cooling with free electrons
Authors: Niguès A. , Siria A. , Verlot P. 
Published: September 2015

AbstractThe ability to cool single ions, atomic ensembles, and more recently macroscopic degrees of freedom down to the quantum ground state has generated considerable progress and perspectives in fundamental and technological science. These major advances have been essentially obtained by coupling mechanical motion to a resonant electromagnetic degree of freedom in what is generally known as laser cooling. Here, we experimentally demonstrate the first self-induced coherent cooling mechanism that is not mediated by an electromagnetic resonance. Using a focused electron beam, we report a 50-fold reduction of the motional temperature of a nanowire. Our result primarily relies on the sub-nanometre confinement of the electron beam and generalizes to any delayed and spatially confined interaction, with important consequences for near-field microscopy and fundamental nanoscale dissipation mechanisms.
An intrinsic timer specifies distal structures of the vertebrate limb
Authors: Saiz-Lopez Patricia , Chinnaiya Kavitha , Campa Victor M. , Delgado Irene , Ros Maria A. , Towers Matthew 
Published: September 2015

AbstractHow the positional values along the proximo-distal axis (stylopod-zeugopod-autopod) of the limb are specified is intensely debated. Early work suggested that cells intrinsically change their proximo-distal positional values by measuring time. Recently, however, it is suggested that instructive extrinsic signals from the trunk and apical ectodermal ridge specify the stylopod and zeugopod/autopod, respectively. Here, we show that the zeugopod and autopod are specified by an intrinsic timing mechanism. By grafting green fluorescent protein-expressing cells from early to late chick wing buds, we demonstrate that distal mesenchyme cells intrinsically time Hoxa13 expression, cell cycle parameters and the duration of the overlying apical ectodermal ridge. In addition, we reveal that cell affinities intrinsically change in the distal mesenchyme, which we suggest results in a gradient of positional values along the proximo-distal axis. We propose a complete model in which a switch from extrinsic signalling to intrinsic timing patterns the vertebrate limb.
Enhancing S-adenosyl-methionine catabolism extends Drosophila lifespan
Authors: Obata Fumiaki , Miura Masayuki 
Published: September 2015

AbstractMethionine restriction extends the lifespan of various model organisms. Limiting S-adenosyl-methionine (SAM) synthesis, the first metabolic reaction of dietary methionine, extends longevity in Caenorhabditis elegans but accelerates pathology in mammals. Here, we show that, as an alternative to inhibiting SAM synthesis, enhancement of SAM catabolism by glycine N-methyltransferase (Gnmt) extends the lifespan in Drosophila. Gnmt strongly buffers systemic SAM levels by producing sarcosine in either high-methionine or low-sams conditions. During ageing, systemic SAM levels in flies are increased. Gnmt is transcriptionally induced in a dFoxO-dependent manner; however, this is insufficient to suppress SAM elevation completely in old flies. Overexpression of gnmt suppresses this age-dependent SAM increase and extends longevity. Pro-longevity regimens, such as dietary restriction or reduced insulin signalling, attenuate the age-dependent SAM increase, and rely at least partially on Gnmt function to exert their lifespan-extending effect in Drosophila. Our study suggests that regulation of SAM levels by Gnmt is a key component of lifespan extension.
Coordination templated [2+2+2] cyclotrimerization in a porous coordination framework
Authors: Wei Yong-Sheng , Zhang Mei , Liao Pei-Qin , Lin Rui-Biao , Li Tai-Yang , Shao Guang , Zhang Jie-Peng , Chen Xiao-Ming 
Published: September 2015

AbstractControlling chemical reactions by the supramolecular confinement effects of nanopores has attracted great attention. Here we show that open metal sites in porous coordination frameworks can constitute more powerful and strict templates for precision syntheses. A Fe(III) dicarboxylate framework functionalized with triangularly arranged metal sites is used to accomplish [2+2+2] cyclotrimerization reactions for organonitrile, alkyne and alkene monomers bearing a geometrically suitable pyridyl group. In situ single-crystal X-ray diffraction facilitates the direct observation of such a coordination templated reaction, before cylcotrimerization, the monomer coordinates at the Fe(III) centre by its pyridyl donor, which forces three unsaturated groups to gather around a position very similar with that of the desired covalent cyclic trimer. After the reaction, the trimers serve as tripodal ligands to perfectly fix the Fe(III) ions and the whole crystal to generate an exceptionally rigid and porous material with large surface area coupled with guest-proof zero thermal expansion.
Suppressed phase transition and giant ionic conductivity in La2Mo2O9 nanowires
Authors: Liu Wei , Pan Wei , Luo Jian , Godfrey Andy , Ou Gang , Wu Hui , Zhang Wei 
Published: September 2015

AbstractImproving the ionic conductivity of solid electrolytes at low temperatures represents a major challenge and an opportunity for enabling a variety of solid-state ionic devices for energy conversion and storage, as well as for environmental protection. Here we report a giant ionic conductivity of 0.20 Scm−1, achieved at 500 °C, in the La2Mo2O9 nanowires with a bamboo-wire morphology, corresponding to a 1000-fold enhancement in conductivity over conventional bulk material. Stabilization of the high-temperature phase is observed to account for about a 10-fold increase in the conductivity. We further demonstrate that fast surface conduction in ∼3 nm thick, partially ordered, surface ‘amorphous’ films, under strain on the curved surfaces of the nanowires (as a non-autonomous surface phase or complexion), contributes to an enhancement of the conductivity by another two orders of magnitude. Exemplified here by the study of the La2Mo2O9 nanowires, new possibilities for improvement of conductivity and for miniaturization of solid-state ionic devices by the careful use of one-dimensional nanomaterials can be envisioned.
Ultrafast multidimensional Laplace NMR for a rapid and sensitive chemical analysis
Authors: Ahola Susanna , Zhivonitko Vladimir V , Mankinen Otto , Zhang Guannan , Kantola Anu M. , Chen Hsueh-Ying , Hilty Christian , Koptyug Igor V. , Telkki Ville-Veikko 
Published: September 2015

AbstractTraditional nuclear magnetic resonance (NMR) spectroscopy relies on the versatile chemical information conveyed by spectra. To complement conventional NMR, Laplace NMR explores diffusion and relaxation phenomena to reveal details on molecular motions. Under a broad concept of ultrafast multidimensional Laplace NMR, here we introduce an ultrafast diffusion-relaxation correlation experiment enhancing the resolution and information content of corresponding 1D experiments as well as reducing the experiment time by one to two orders of magnitude or more as compared with its conventional 2D counterpart. We demonstrate that the method allows one to distinguish identical molecules in different physical environments and provides chemical resolution missing in NMR spectra. Although the sensitivity of the new method is reduced due to spatial encoding, the single-scan approach enables one to use hyperpolarized substances to boost the sensitivity by several orders of magnitude, significantly enhancing the overall sensitivity of multidimensional Laplace NMR.
Regulation of NKT cell-mediated immune responses to tumours and liver inflammation by mitochondrial PGAM5-Drp1 signalling
Authors: Kang Young Jun , Bang Bo-Ram , Han Kyung Ho , Hong Lixin , Shim Eun-Jin , Ma Jianhui , Lerner Richard A. , Otsuka Motoyuki 
Published: September 2015

AbstractThe receptor-interacting protein kinase 3 (RIPK3) plays crucial roles in programmed necrosis and innate inflammatory responses. However, a little is known about the involvement of RIPK3 in NKT cell-mediated immune responses. Here, we demonstrate that RIPK3 plays an essential role in NKT cell function via activation of the mitochondrial phosphatase phosphoglycerate mutase 5 (PGAM5). RIPK3-mediated activation of PGAM5 promotes the expression of cytokines by facilitating nuclear translocation of NFAT and dephosphorylation of dynamin-related protein 1 (Drp1), a GTPase is essential for mitochondrial homoeostasis. Ripk3−/− mice show reduced NKT cell responses to metastatic tumour cells, and both deletion of RIPK3 and pharmacological inhibition of Drp1 protects mice from NKT cell-mediated induction of acute liver damage. Collectively, the results identify a crucial role for RIPK3-PGAM5-Drp1/NFAT signalling in NKT cell activation, and further suggest that RIPK3-PGAM5 signalling may mediate crosstalk between mitochondrial function and immune signalling.
Strong frequency dependence of vibrational relaxation in bulk and surface water reveals sub-picosecond structural heterogeneity
Authors: van der Post Sietse T. , Hsieh Cho-Shuen , Okuno Masanari , Nagata Yuki , Bakker Huib J. , Bonn Mischa , Hunger Johannes 
Published: September 2015

AbstractBecause of strong hydrogen bonding in liquid water, intermolecular interactions between water molecules are highly delocalized. Previous two-dimensional infrared spectroscopy experiments have indicated that this delocalization smears out the structural heterogeneity of neat H2O. Here we report on a systematic investigation of the ultrafast vibrational relaxation of bulk and interfacial water using time-resolved infrared and sum-frequency generation spectroscopies. These experiments reveal a remarkably strong dependence of the vibrational relaxation time on the frequency of the OH stretching vibration of liquid water in the bulk and at the air/water interface. For bulk water, the vibrational relaxation time increases continuously from 250 to 550 fs when the frequency is increased from 3,100 to 3,700 cm−1. For hydrogen-bonded water at the air/water interface, the frequency dependence is even stronger. These results directly demonstrate that liquid water possesses substantial structural heterogeneity, both in the bulk and at the surface.
miR-34/449 control apical actin network formation during multiciliogenesis through small GTPase pathways
Authors: Chevalier Benoît , Adamiok Anna , Mercey Olivier , Revinski Diego R. , Zaragosi Laure-Emmanuelle , Pasini Andrea , Kodjabachian Laurent , Barbry Pascal , Marcet Brice 
Published: September 2015

AbstractVertebrate multiciliated cells (MCCs) contribute to fluid propulsion in several biological processes. We previously showed that microRNAs of the miR-34/449 family trigger MCC differentiation by repressing cell cycle genes and the Notch pathway. Here, using human and Xenopus MCCs, we show that beyond this initial step, miR-34/449 later promote the assembly of an apical actin network, required for proper basal bodies anchoring. Identification of miR-34/449 targets related to small GTPase pathways led us to characterize R-Ras as a key regulator of this process. Protection of RRAS messenger RNA against miR-34/449 binding impairs actin cap formation and multiciliogenesis, despite a still active RhoA. We propose that miR-34/449 also promote relocalization of the actin binding protein Filamin-A, a known RRAS interactor, near basal bodies in MCCs. Our study illustrates the intricate role played by miR-34/449 in coordinating several steps of a complex differentiation programme by regulating distinct signalling pathways.
Full-length soluble urokinase plasminogen activator receptor down-modulates nephrin expression in podocytes
Authors: Alfano Massimo , Cinque Paola , Giusti Guido , Proietti Silvia , Nebuloni Manuela , Danese Silvio , D’Alessio Silvia , Genua Marco , Portale Federica , Lo Porto Manuela , Singhal Pravin C. , Rastaldi Maria Pia , Saleem Moin A. , Mavilio Domenico , Mikulak Joanna 
Published: September 2015

AbstractIncreased plasma level of soluble urokinase-type plasminogen activator receptor (suPAR) was associated recently with focal segmental glomerulosclerosis (FSGS). In addition, different clinical studies observed increased concentration of suPAR in various glomerular diseases and in other human pathologies with nephrotic syndromes such as HIV and Hantavirus infection, diabetes and cardiovascular disorders. Here, we show that suPAR induces nephrin down-modulation in human podocytes. This phenomenon is mediated only by full-length suPAR, is time-and dose-dependent and is associated with the suppression of Wilms’ tumor 1 (WT-1) transcription factor expression. Moreover, an antagonist of αvβ3 integrin RGDfv blocked suPAR-induced suppression of nephrin. Thesein vitrodata were confirmed in anin vivouPAR knock out Plaur−/−mice model by demonstrating that the infusion of suPAR inhibits expression of nephrin and WT-1 in podocytes and induces proteinuria. This study unveiled that interaction of full-length suPAR with αvβ3 integrin expressed on podocytes results in down-modulation of nephrin that may affect kidney functionality in different human pathologies characterized by increased concentration of suPAR.
Role of Src in Vascular Hyperpermeability Induced by Advanced Glycation End Products
Authors: Zhang Weijin , Xu Qiulin , Wu Jie , Zhou Xiaoyan , Weng Jie , Xu Jing , Wang Weiju , Huang Qiaobing , Guo Xiaohua 
Published: September 2015

AbstractThe disruption of microvascular barrier in response to advanced glycation end products (AGEs) stimulation contributes to vasculopathy associated with diabetes mellitus. Here, to study the role of Src and its association with moesin, VE-cadherin and focal adhesion kinase (FAK) in AGE-induced vascular hyperpermeability, we verified that AGE induced phosphorylation of Src, causing increased permeability in HUVECs. Cells over-expressed Src displayed a higher permeability after AGE treatment, accompanied with more obvious F-actin rearrangement. Activation of Src with pcDNA3/flag-SrcY530F alone duplicated these effects. Inhibition of Src with siRNA, PP2 or pcDNA3/flag-SrcK298M abolished these effects. The pulmonary microvascular endothelial cells (PMVECs) isolated from receptor for AGEs (RAGE)-knockout mice decreased the phosphorylation of Src and attenuated the barrier dysfunction after AGE-treatment. In vivo study showed that the exudation of dextran from mesenteric venules was increased in AGE-treated mouse. This was attenuated in RAGE knockout or PP2-pretreated mice. Up-regulation of Src activity induced the phosphorylation of moesin, as well as activation and dissociation of VE-cadherin, while down-regulation of Src abolished these effects. FAK was also proved to interact with Src in HUVECs stimulated with AGEs. Our studies demonstrated that Src plays a critical role in AGE-induced microvascular hyperpermeability by phosphorylating moesin, VE-cadherin and FAK respectively.
Genetic Variants in the Insulin-like Growth Factor Pathway and Colorectal Cancer Risk in the Netherlands Cohort Study
Authors: Simons Colinda C. J. M. , Schouten Leo J. , Godschalk Roger W. L. , van Engeland Manon , van den Brandt Piet A. , van Schooten Frederik J. , Weijenberg Matty P. 
Published: September 2015

AbstractInterrelationships between insulin-like growth factors (IGFs), hyperinsulinaemia, diabetes and colorectal cancer (CRC) indicate involvement of IGFs in colorectal tumorigenesis. We investigated the CRC risk associated with 24 single nucleotide polymorphisms (SNPs) in 9 genes related to the IGF pathway and an IGF1 19-CA repeat polymorphism. Variants were selected from literature and genotyped in toenail DNA from 3,768 subcohort members and 2,580 CRC cases from the Netherlands Cohort Study, which has a case-cohort design (n = 120,852). We used the follow-up period 1986–2002. Eighteen SNPs were unequivocally associated with selected endpoints in the literature and unfavorable alleles were aggregated into a genetic sum score. Cox regression showed that a higher genetic sum score significantly increased CRC risk at all subsites, except the rectum, in men (highest vs. lowest tertile: HR for CRC = 1.36, 95% CI: 1.11, 1.65; P-trend = 0.002). Single SNPs (except the IGF1 SNP rs5742694) were not associated with risk. Models including the total number of IGF1 19-CA repeats showed CRC risk was halved at all subsites in women carrying <38 repeats but not >38 repeats (≤36 versus 38 repeats: HR for CRC = 0.44; 95% CI: 0.33, 0.58; P-trend < 0.001). These findings support a role for variants in IGF-related genes in colorectal tumorigenesis.
Quasi-two-dimensional superconductivity in FeSe0.3Te0.7 thin films and electric-field modulation of superconducting transition
Authors: Lin Zhu , Mei Chenguang , Wei Linlin , Sun Zhangao , Wu Shilong , Huang Haoliang , Zhang Shu , Liu Chang , Feng Yang , Tian Huanfang , Yang Huaixin , Li Jianqi , Wang Yayu , Zhang Guangming , Lu Yalin , Zhao Yonggang 
Published: September 2015

AbstractWe report the structural and superconducting properties of FeSe0.3Te0.7 (FST) thin films with different thicknesses grown on ferroelectric Pb(Mg1/3Nb2/3)0.7Ti0.3O3 substrates. It was shown that the FST films undergo biaxial tensile strains which are fully relaxed for films with thicknesses above 200 nm. Electrical transport measurements reveal that the ultrathin films exhibit an insulating behavior and superconductivity appears for thicker films with Tc saturated above 200 nm. The current-voltage curves around the superconducting transition follow the Berezinskii-Kosterlitz-Thouless (BKT) transition behavior and the resistance-temperature curves can be described by the Halperin–Nelson relation, revealing quasi-two-dimensional phase fluctuation in FST thin films. The Ginzburg number decreases with increasing film thickness indicating the decrease of the strength of thermal fluctuations. Upon applying electric field to the heterostructure, Tc of FST thin film increases due to the reduction of the tensile strain in FST. This work sheds light on the superconductivity, strain effect as well as electric-field modulation of superconductivity in FST films.
Large Scale Synthesis and Light Emitting Fibers of Tailor-Made Graphene Quantum Dots
Authors: Park Hun , Hyun Noh Sung , Hye Lee Ji , Jun Lee Won , Yun Jaung Jae , Geol Lee Seung , Hee Han Tae 
Published: September 2015

AbstractGraphene oxide (GO), which is an oxidized form of graphene, has a mixed structure consisting of graphitic crystallites of sp2 hybridized carbon and amorphous regions. In this work, we present a straightforward route for preparing graphene-based quantum dots (GQDs) by extraction of the crystallites from the amorphous matrix of the GO sheets. GQDs with controlled functionality are readily prepared by varying the reaction temperature, which results in precise tunability of their optical properties. Here, it was concluded that the tunable optical properties of GQDs are a result of the different fraction of chemical functionalities present. The synthesis approach presented in this paper provides an efficient strategy for achieving large-scale production and long-time optical stability of the GQDs and the hybrid assembly of GQD and polymer has potential applications as photoluminescent fibers or films.