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See detailThe tumour suppressor Ras-association domain family protein 1A (RASSF1A) regulates TNF-alpha signalling in cardiomyocytes.
Mohamed, Tamer M. A.; Zi, Min; Prehar, Sukhpal et al

in Cardiovascular research (2014), 103(1), 47-59

AIMS: Tumour necrosis factor-alpha (TNF-alpha) plays a key role in the regulation of cardiac contractility. Although cardiomyocytes are known to express the TNF-alpha receptors (TNFRs), the mechanism of ... [more ▼]

AIMS: Tumour necrosis factor-alpha (TNF-alpha) plays a key role in the regulation of cardiac contractility. Although cardiomyocytes are known to express the TNF-alpha receptors (TNFRs), the mechanism of TNF-alpha signal transmission is incompletely understood. The aim of this study was to investigate whether the tumour suppressor Ras-association domain family protein 1 isoform A (RASSF1A) modulates TNF-alpha signalling in cardiomyocytes. METHODS AND RESULTS: We used RASSF1A knockout (RASSF1A(-/-)) mice and wild-type (WT) littermates in this study. Acute stimulation with a low dose of TNF-alpha (10 microg/kg iv) increased cardiac contractility and intracellular calcium transients' amplitude in WT mice. In contrast, RASSF1A(-/-) mice showed a blunted contractile response. Mechanistically, RASSF1A was essential in the formation of the TNFR complex (TNFRC), where it functions as an adaptor molecule to facilitate the recruitment of TNFR type 1-associated death domain protein and TNFR-associated factor 2 to form the TNF-alpha receptor complex. In the absence of RASSF1A, signal transmission from the TNF-alpha receptor complex to the downstream effectors, such as cytoplasmic phospholipase A2 and protein kinase A, was attenuated leading to the reduction in the activation of calcium handling molecules, such as L-type Ca(2+) channel and ryanodine receptors. CONCLUSION: Our data indicate an essential role of RASSF1A in regulating TNF-alpha signalling in cardiomyocytes, with RASSF1A being key in the formation of the TNFRC and in signal transmission to the downstream targets. [less ▲]

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See detailTUNA: TUning Naturalness-based Analysis
Jimenez, Matthieu UL; Cordy, Maxime UL; Le Traon, Yves UL et al

in 34th IEEE International Conference on Software Maintenance and Evolution, Madrid, Spain, 26-28 September 2018 (2018, September 26)

Natural language processing techniques, in particular n-gram models, have been applied successfully to facilitate a number of software engineering tasks. However, in our related ICSME ’18 paper, we have ... [more ▼]

Natural language processing techniques, in particular n-gram models, have been applied successfully to facilitate a number of software engineering tasks. However, in our related ICSME ’18 paper, we have shown that the conclusions of a study can drastically change with respect to how the code is tokenized and how the used n-gram model is parameterized. These choices are thus of utmost importance, and one must carefully make them. To show this and allow the community to benefit from our work, we have developed TUNA (TUning Naturalness-based Analysis), a Java software artifact to perform naturalness-based analyses of source code. To the best of our knowledge, TUNA is the first open- source, end-to-end toolchain to carry out source code analyses based on naturalness. [less ▲]

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See detailTunable magnetoplasmonics in lattices of Ni/SiO2/Au dimers
Pourjamal, Sara; Kataja, Mikko; Maccaferri, Nicolò UL et al

in Scientific Reports (2019), 9

We present a systematic study on the optical and magneto-optical properties of Ni/SiO2/Au dimer lattices. By consideringthe excitation of orthogonal dipoles in the Ni and Au nanodisks, we analytically ... [more ▼]

We present a systematic study on the optical and magneto-optical properties of Ni/SiO2/Au dimer lattices. By consideringthe excitation of orthogonal dipoles in the Ni and Au nanodisks, we analytically demonstrate that the magnetoplasmonicresponse of dimer lattices is governed by a complex interplay of near- and far-field interactions. Near-field coupling betweendipoles in Ni and low-loss Au enhances the polarizabilty of single dimers compared to that of isolated Ni nanodisks. Far-fielddiffractive coupling in periodic lattices of these two particle types enlarges the difference in effective polarizability further.This effect is explained by an inverse relationship between the damping of collective surface lattice resonances and theimaginary polarizability of individual scatterers. Optical reflectance measurements, magneto-optical Kerr effect spectra, andfinite-difference time-domain simulations confirm the analytical results. Hybrid dimer arrays supporting intense plasmonexcitations are a promising candidate for active magnetoplasmonic devices. [less ▲]

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See detailTuneable Multicoloured Patterns From Photonic Cross Communication Between Cholesteric Liquid Crystal Droplets
Noh, Junghyun UL; Liang, Hsin-Ling; Drevensek-Olenik, Irena et al

in Journal of Materials Chemistry C (2014), 2(5), 806-810

Monodisperse droplets of planar-aligned cholesteric (N*) liquid crystal exhibit an intriguing capacity for photonic cross-communication, giving rise to colourful patterns that depend sensitively on the N ... [more ▼]

Monodisperse droplets of planar-aligned cholesteric (N*) liquid crystal exhibit an intriguing capacity for photonic cross-communication, giving rise to colourful patterns that depend sensitively on the N* pitch, droplet positions and illuminated area. The phenomenon results from a combination of omnidirectional selective reflection of N* droplets—which thus act as spherically symmetric self-assembled photonic crystals—and total internal reflection at the continuous phase surface. We outline how the unique optical properties can be employed in numerous applications. [less ▲]

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See detailTuning Intermolecular Interactions with Nanostructured Environments
Chattopadhyaya, Mausumi; Hermann, Jan; Poltavsky, Igor et al

in Chemistry of Materials (2016), ASAP

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See detailTuning Self-Assembly in Liquid Crystal shells: from Interfacial- to Polymer-stabilization
Noh, Junghyun UL

Doctoral thesis (2018)

Liquid crystals form a subclass of soft materials which is easily influenced and deformed by a surface, an interface and the geometry. Of particular interest, in this thesis, is the confinement of liquid ... [more ▼]

Liquid crystals form a subclass of soft materials which is easily influenced and deformed by a surface, an interface and the geometry. Of particular interest, in this thesis, is the confinement of liquid crystals in shell geometry, imposing real or virtual defects that the liquid crystal cannot avoid. With the help of microfluidics, we prepare our research platform, liquid crystal shells, which contain and are surrounded by aqueous phases. In order to maintain such a shell structure in the aqueous phases, immiscible with the liquid crystal, appropriate stabilization is required. Here we explore two different pathways of interfacial stabilization and polymer stabilization and their impact on liquid crystal self-assembly. We primarily use either a polymeric or an ionic surfactant dissolving in water to stabilize shells and tune boundary conditions of shells. Depending on symmetrically or asymmetrically imposed boundary conditions, the nematic–isotropic phase transition appears as a single transi- tion or separated into two steps. We propose that the latter phenomenon can be understood as a result of an ordering-enhancing effect by surfactants. The nematic–smectic A phase transition is also investigated under varying boundary conditions. With a precise temperature control, we explore equilibrium smectic structures and introduce a new arrangement of focal conic arrays in shell geometry. Beyond stabilizing the shell from the shell exterior, but we also incorporate a photosensitive surface agent within the shell, enabling dynamic and reversible photoswitching of the liquid crystal alignment in real time. However, shells with interfacial stabilization cannot survive more than several weeks due to their intrinsic fluid interfaces. In particular, a liquid crystal shell can serve as a permeable mem- brane which lets the constituents of aqueous phases pass through, giving a significant influence on the liquid crystalline order. To tame liquid crystal self-assembly and make the shell struc- ture permanent, we use photopolymerization to stabilize the shells. With only 5% monomer, the entire configuration of each liquid crystal shell is locked and shell lifetime extends beyond several months. The liquid crystalline order is visualized on the nanoscale via the polymer network and we further demonstrate that the shell configurations can be a unique template for creating complex polymer networks. Finally a new experimental approach is introduced to making ultrathin shells and several issues on shell instability and alignment determination are addressed. [less ▲]

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See detailTuning the defect configurations in nematic and smectic liquid crystalline shells.
Liang, H. L.; Noh, Junghyun UL; Zentel, R. et al

in Philosophical Transactions of the Royal Society of London. Series A : Mathematical and Physical Sciences (2013), 371(1988), 20120258

Thin liquid crystalline shells surrounding and surrounded by aqueous phases can be conveniently produced using a nested capillary microfluidic system, as was first demonstrated by Fernandez-Nieves et al ... [more ▼]

Thin liquid crystalline shells surrounding and surrounded by aqueous phases can be conveniently produced using a nested capillary microfluidic system, as was first demonstrated by Fernandez-Nieves et al. in 2007. By choosing particular combinations of stabilizers in the internal and external phases, different types of alignment, uniform or hybrid, can be ensured within the shell. Here, we investigate shells in the nematic and smectic phases under varying boundary conditions, focusing in particular on textural transformations during phase transitions, on the interaction between topological defects in the director field and inclusions in the liquid crystal (LC), and on the possibility to relocate defects within the shell by rotating the shell in the gravitational field. We demonstrate that inclusions in a shell can seed defects that cannot form in a pristine shell, adding a further means of tuning the defect configuration, and that shells in which the internal aqueous phase is not density matched with the LC will gently rearrange the internal structure upon a rotation that changes the influence of gravity. Because the defects can act as anchor points for added linker molecules, allowing self-assembly of adjacent shells, the various arrangements of defects developing in these shells and the possibility of tuning the result by modifying boundary conditions, LC phase, thickness and diameter of the shell or applying external forces make this new LC configuration very attractive. [less ▲]

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See detailTuning the Magneto-Optical Response of Nanosize Ferromagnetic Ni Disks Using the Phase of Localized Plasmons
Maccaferri, Nicolò UL; Berger, Andreas; Bonetti, Stefano et al

in Physical Review Letters (2013), 111(16), 167401

We explore the influence of the phase of localized plasmon resonances on the magneto-optical activity of nanoferromagnets. We demonstrate that these systems can be described as two orthogonal damped ... [more ▼]

We explore the influence of the phase of localized plasmon resonances on the magneto-optical activity of nanoferromagnets. We demonstrate that these systems can be described as two orthogonal damped oscillators coupled by the spin-orbit interaction. We prove that only the spin-orbit induced transverse plasmon plays an active role on the magneto-optical properties by controlling the relative amplitude and phase lag between the two oscillators. Our theoretical predictions are fully confirmed by magneto-optical Kerr effect and optical extinction measurements in nanostructures of different size and shape. [less ▲]

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See detailTuning the Pseudospin Polarization of Graphene by a Pseudomagnetic Field
Georgi, Alexander; Nemes-Incze, Peter; Carrillo-Bastos, Ramon et al

in Nano Letters (2017), 17

One of the intriguing characteristics of honeycomb lattices is the appearance of a pseudomagnetic field as a result of mechanical deformation. In the case of graphene, the Landau quantization resulting ... [more ▼]

One of the intriguing characteristics of honeycomb lattices is the appearance of a pseudomagnetic field as a result of mechanical deformation. In the case of graphene, the Landau quantization resulting from this pseudomagnetic field has been measured using scanning tunneling microscopy. Here we show that a signature of the pseudomagnetic field is a local sublattice symmetry breaking observable as a redistribution of the local density of states. This can be interpreted as a polarization of graphene’s pseudospin due to a strain induced pseudomagnetic field, in analogy to the alignment of a real spin in a magnetic field. We reveal this sublattice symmetry breaking by tunably straining graphene using the tip of a scanning tunneling microscope. The tip locally lifts the graphene membrane from a SiO2 support, as visible by an increased slope of the I(z) curves. The amount of lifting is consistent with molecular dynamics calculations, which reveal a deformed graphene area under the tip in the shape of a Gaussian. The pseudomagnetic field induced by the deformation becomes visible as a sublattice symmetry breaking which scales with the lifting height of the strained deformation and therefore with the pseudomagnetic field strength. Its magnitude is quantitatively reproduced by analytic and tight-binding models, revealing fields of 1000 T. These results might be the starting point for an effective THz valley filter, as a basic element of valleytronics. [less ▲]

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See detailTuning the spectral sensitivity of vertical InN nanopyramid based photodetectors by means of band gap engineering and/or nanostructure size control
Trellenkamp, Stefan; Mikulics, Martin; Winden, Andreas et al

in ASDAM 2012, The Ninth International Conference on Advanced Semiconductor Devices and Microsystems (2012)

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See detailTuning the work function of stepped metal surfaces by adsorption of organic molecules
Jiang, Yingda; Li, Jingtai; Su, Guirong et al

in Journal of Physics : Condensed Matter (2017), 29

Understanding the binding mechanisms for aromatic molecules on transition-metal surfaces, especially with defects such as vacancies, steps and kinks, is a major challenge in designing functional ... [more ▼]

Understanding the binding mechanisms for aromatic molecules on transition-metal surfaces, especially with defects such as vacancies, steps and kinks, is a major challenge in designing functional interfaces for organic devices. One important parameter in the performance of organic/inorganic devices is the barrier of charge carrier injection. In the case of a metallic electrode, tuning the electronic interface potential or the work function for electronic level alignment is crucial. Here, we use density-functional theory (DFT) calculations with van der Waals (vdW) interactions treated with both screened pairwise (vdWsurf) and many-body dispersion (MBD) methods, to systematically study the interactions of benzene with a variety of stepped surfaces. Our calculations confirm the physisorptive character of Ag(2 1 1), Ag(5 3 3), Ag(3 2 2), Ag(7 5 5) and Ag(5 4 4) surfaces upon the adsorption of benzene. The MBD effects reduce the adsorption energies by about 0.15 eV per molecule compared to the results from the DFT + vdWsurf method. In addition, we find that the higher the step density, the larger the reduction of the work function upon the adsorption of benzene. We also study the effect of vdW interactions on the electronic structure using a fully selfconsistent implementation of the vdWsurf method in the Kohn–Sham DFT framework. We find that the self-consistent vdWsurf effects increase the work function due to the lowered Fermi level and the increased vacuum level. As a result, the benzene/Ag(2 1 1) system has the lowest work function (3.67 eV) among the five adsorption systems, significantly smaller than the work function of the clean Ag(1 1 1) surface (4.74 eV). Our results provide important insights into the stability and electronic properties of molecules adsorbed on stepped metal surfaces, which could help in designing more appropriate interfaces with low work functions for electron transfer. [less ▲]

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See detailTunneling between helical Majorana modes and helical Luttinger liquids
Chao, Sung-Po; Schmidt, Thomas UL; Chung, Chung-Hou

in Physical Review B (2015), 91

We propose and study the charge transport through single and double quantum point contacts setup between helical Majorana modes and an interacting helical Luttinger liquid. We show that the differential ... [more ▼]

We propose and study the charge transport through single and double quantum point contacts setup between helical Majorana modes and an interacting helical Luttinger liquid. We show that the differential conductance decreases for stronger repulsive interactions and that the point contacts become insulating above a critical interaction strength. For a single-point contact, the differential conductance as a function of bias voltage shows a series of peaks due to Andreev reflection of electrons in the Majorana modes. In the case of two point contacts, interference phenomena make the structure of the individual resonance peaks less universal and show modulations with different separation distance between the contacts. For small separation distance, the overall features remain similar to the case of a single-point contact. [less ▲]

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See detailTunneling Conductivity in Composites of Attractive Colloids
Nigro, Biagio; Grimaldi, Claudio; Miller, M.A. et al

in Journal of Chemical Physics (2012), 136(164903), 1-5

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See detailTurbo Decoding: Why Stopping Criteria do Work
Heim, Axel; Sorger, Ulrich UL

in Proc. 5th International Symposium on Turbo Codes & Related Topics (2008)

The convergence of iterative decoding schemes is considered. The class of dually coupled codes is recalled, being a super class to both Turbo and LDPC codes. It is proven that the output L-values of a ... [more ▼]

The convergence of iterative decoding schemes is considered. The class of dually coupled codes is recalled, being a super class to both Turbo and LDPC codes. It is proven that the output L-values of a Turbo decoder cannot grow to in?nity, while those of an LDPC decoder can. Finally, a new decoder parameter is introduced by which the convergence behavior can be controlled. [less ▲]

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See detailTurkish Immigration Politics and the Syrian Refugee Crisis
Hoffmann, Sophia; Samuk, Sahizer UL

E-print/Working paper (2016)

Detailed reference viewed: 60 (1 UL)