Read by QxMD icon Read


E Gershnabel, I Sh Averbukh
We study interaction of generic asymmetric molecules with laser fields having twisted polarization, using a pair of strong time-delayed short laser pulses with crossed linear polarizations as an example. We show that such an excitation not only provides unidirectional rotation of the most polarizable molecular axis, but also induces a directed torque along this axis, which results in a transient orientation of the molecules. The asymmetric molecules are chiral in nature and different molecular enantiomers experience the orienting action in opposite directions causing out-of-phase oscillations of their dipole moments...
February 23, 2018: Physical Review Letters
D Giusti, V Lubicz, C Tarantino, G Martinelli, C T Sachrajda, F Sanfilippo, S Simula, N Tantalo
The leading-order electromagnetic and strong isospin-breaking corrections to the ratio of K_{μ2} and π_{μ2} decay rates are evaluated for the first time on the lattice, following a method recently proposed. The lattice results are obtained using the gauge ensembles produced by the European Twisted Mass Collaboration with N_{f}=2+1+1 dynamical quarks. Systematic effects are evaluated and the impact of the quenched QED approximation is estimated. Our result for the correction to the tree-level K_{μ2}/π_{μ2} decay ratio is -1...
February 16, 2018: Physical Review Letters
Zehang Zhou, Weerapha Panatdasirisuk, Tyler S Mathis, Babak Anasori, Canhui Lu, Xinxing Zhang, Zhiwei Liao, Yury Gogotsi, Shu Yang
Free-standing, highly flexible and foldable supercapacitor electrodes were fabricated through the spray-coating assisted layer-by-layer assembly of Ti3 C2 Tx (MXene) nanoflakes together with multi-walled carbon nanotubes (MWCNTs) on electrospun polycaprolactone (PCL) fiber networks. The open structure of the PCL network and the use of MWCNTs as spacers not only limit the restacking of Ti3 C2 Tx flakes but also increase the accessible surface of the active materials, facilitating fast diffusion of electrolyte ions within the electrode...
March 15, 2018: Nanoscale
Juan Zhao, Zhihe Chi, Zhan Yang, Xiaojie Chen, Michael S Arnold, Yi Zhang, Jiarui Xu, Zhenguo Chi, Matthew P Aldred
Truly stretchable electronics, wherein all components themselves permit elastic deformation as the whole devices are stretched, exhibit unique advantages over other strategies, such as simple fabrication process, high integrity of entire components and intimate integration with curvilinear surfaces. In contrast to the stretchable devices using stretchable interconnectors to integrate with rigid active devices, truly stretchable devices are realized with or without intentionally employing structural engineering (e...
March 15, 2018: Nanoscale
Elizabeth M Wakefield, Casey Hall, Karin H James, Susan Goldin-Meadow
Verb learning is difficult for children (Gentner, ), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, ). Here we investigate how well 4- and 5-year-old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24-hour delay...
March 15, 2018: Developmental Science
Victor Feliz Pedrinha, Juliana Melo da Silva Brandão, Oscar Faciola Pessoa, Patrícia de Almeida Rodrigues
Advances in endodontics have enabled the evolution of file manufacturing processes, improving performance beyond that of conventional files. In the present study, systems manufactured using state of the art methods and possessing special properties related to NiTi alloys ( i.e ., CM-Wire, M-Wire and R-Phase) were selected. The aim of this review was to provide a detailed analysis of the literature about the relationship between recently introduced NiTi files with different movement kinematics and shaping ability, apical extrusion of debris and dentin defects in root canal preparations...
2018: Open Dentistry Journal
Jing Zhang, Yinghong Cui, Shuwen Sun, Jianguo Cao, Xiaoling Fang
Casticin inhibits migration, invasion and induced apoptosis in numerous cancer cells; however, the Hedgehog (Hh) signaling pathway is a key factor in the epithelial-mesenchymal transition (EMT). The present study aimed to assess whether casticin affects the expression of members of the Hh signaling pathway and EMT effectors in ovarian carcinoma. The ovarian cancer SKOV3 cell line was incubated in the presence of various concentrations of casticin or cyclopamine. Next, the expression levels of the main Hh signaling effector glioma-associated oncogene-1 (Gli-1) and EMT-associated factors [Twist-related protein 1 (Twist1), E-cadherin and N-cadherin] were determined by western blotting and reverse transcription-quantitative polymerase chain reaction...
April 2018: Oncology Letters
Jihwan Myung, Christoph Schmal, Sungho Hong, Yoshiaki Tsukizawa, Pia Rose, Yong Zhang, Michael J Holtzman, Erik De Schutter, Hanspeter Herzel, Grigory Bordyugov, Toru Takumi
Mammalian circadian clocks have a hierarchical organization, governed by the suprachiasmatic nucleus (SCN) in the hypothalamus. The brain itself contains multiple loci that maintain autonomous circadian rhythmicity, but the contribution of the non-SCN clocks to this hierarchy remains unclear. We examine circadian oscillations of clock gene expression in various brain loci and discovered that in mouse, robust, higher amplitude, relatively faster oscillations occur in the choroid plexus (CP) compared to the SCN...
March 14, 2018: Nature Communications
Nazario Martin, Alicia López-Andarias, Javier López-Andarias, Carmen Atienza, Francisco J Chichón, José L Carrascosa
Supramolecular chemistry has evolved from the traditional focus on thermodynamic on-pathways to the complex study of kinetic off-pathways, which are strongly dependent of the environmental conditions. Moreover, the control over pathway complexity allows obtaining nanostructures that are inaccessible through spontaneous thermodynamic processes. Here, we present a family of peptide-based π-extended tetrathiafulvalene (exTTF) molecules which show two self-assembly pathways leading to two distinct J-aggregates, namely metastable (M) and thermodynamic (T), with different spectroscopic, chiroptical and electrochemical behavior...
March 14, 2018: Chemistry: a European Journal
Yanpeng Zhu, Zeming Xia, Zeying Cai, Ziyong Yuan, Nianqiang Jiang, Tao Li, Yonggen Wang, Xiaoyu Guo, Zhihao Li, Shuang Ma, Dingyong Zhong, Yang Li, Jiaobing Wang
We report the synthesis and characterization of two hexapole [7]helicenes (H7Hs). Single crystal X-ray diffraction unambiguously confirms the molecular structure. H7H absorbs light, with distinct Cotton effect, from ultraviolet to the near infrared (λmax = 618 nm). Cyclic voltammetry reveals nine reversible redox states, consecutively from -2 to +6. These chiroptical and electronic properties of H7H are inaccessible from helicene's small homologues.
March 14, 2018: Journal of the American Chemical Society
Jiangman Sun, Ping Cai, Feilong Pan, Lianjie Zhang, Zhulin Liu, Zhitian Liu, Yong Cao, Junwu Chen
A 5,6-difluorobenzothiazole (ffBTz) based dibromo monomer was successfully synthesized, from which new fluorinated conjugated polymers PF-ffBTz and PFN-ffBTz were prepared via copolymerizations with two fluorene based diboronic ester monomers. Twisted fluorene-ffBTz backbones enable PF-ffBTz and PFN-ffBTz with large band gaps up to 3.10 eV and deep-lying HOMO levels down to 6.2 eV. The chemical structures of PF-ffBTz and PFN-ffBTz impart some new functionalities of fluorinated conjugated polymers. PF-ffBTz can show deep blue electroluminescent (EL) emission, with high external quantum efficiency (EQE) of 3...
March 13, 2018: ACS Applied Materials & Interfaces
Lisa V Poulikakos, Prachi Thureja, Alexia Stollmann, Eva De Leo, David J Norris
Chiral metallic nanostructures can generate evanescent fields which are more highly twisted than circularly polarized light. However, it remains unclear how best to exploit this phenomenon, hindering the optimal utilization of chiral electromagnetic fields. Here, inspired by optical antenna theory, we address this challenge by introducing chiral antenna parameters: the chirality flux efficiency and the chiral antenna aperture. These quantities, which are based on chirality conservation, quantify the generation and dissipation of chiral light...
March 13, 2018: Nano Letters
Thonimar Vieira Alencar, Driele von Dreifus, Maria Gabriela Cota Moreira, Gomes S N Eliel, Chao-Hui Yeh, Po-Wen Chiu, Marcos A Pimenta, Leandro Malard, Ana M de Paula
We report on photoluminescence emission imaging by femtosecond laser excitation on twisted bilayer graphene samples. The emission images are obtained by tuning the excitation laser energies in the near infrared region. We demonstrate an increase of the photoluminescence emission at excitation energies that depends on the bilayer twist angle. The results show a peak for the light emission when the excitation is in resonance with transitions at the van Hove singularities in the electronic density of states. We measured the photoluminescence excitation peak position and width for samples with various twist angles showing resonances in the energy range of 1...
March 13, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Lukas Nico Wirz, Maria Dimitrova, Heike Fliegl, Dage Sundholm
The topology of twisted molecular rings is characterized by the linking number, which is equal to the sum of the twist and writhe parameters. The twist is associated with the local twisting of the molecular frame, whereas the writhe is a global property of the molecular ring. The writhe represents the bending of the molecular ring, which increases π-electron stabilization as well as steric interactions and reduces the strain of twisted molecular rings. In this work, we investigate a number of cyclic all-trans C40 H40 annulenes with different topologies and their dications...
March 13, 2018: Journal of Physical Chemistry Letters
Hossein Rokni, Wei Lu
We combine conductive atomic force microscopy (CAFM) and molecular dynamics (MD) simulations to reveal the interaction of atomically thin layered materials (ATLMs) down to nanoscale lateral dimension. The setup also allows quantifying, for the first time, the effect of layer number and electric field on the dielectric constant of ATLMs with few-layer down to monolayer thickness. Our CAFM-assisted electrostatic technique shows that high-quality mono- and bilayer graphene is reliably produced at significant yields only by the shear type of bond breaking between layers, whereas the normal type of bond breaking exhibits a very stochastic process mainly due to the coexistence of local delamination and interlayer twist...
February 28, 2018: ACS Central Science
GuangLiang Jiang, QingFeng Hu, Hui Wang, WeiHong Ding, Ning Zhang, YiShuo Wu, QiDong Zhou, ChuanYu Sun, GuoWei Xia, Qiang Ding, Rong Na, Ke Xu
BACKGROUND: Epithelial-mesenchymal transition (EMT) was reported to have an important effect on malignant metastasis; however, it remained largely unknown if EMT marker expression of neoplastic tissue had predictive value for prognosis of prostate cancer. METHODS: We searched for published studies which measured EMT marker expression and analyzed its association with clinical outcomes of patients after Radical Prostatectomy (RP). We reviewed and pooled-analyzed the association of EMT marker expression and biochemical recurrence-free survival (BFS), as well as the difference in strong or weak expression of EMT markers in tumors of high Gleason score (≥8)...
January 2018: Annals of Clinical and Laboratory Science
Asli Yildirim, Michael Feig
High-resolution three-dimensional models of Caulobacter crescentus nucleoid structures were generated via a multi-scale modeling protocol. Models were built as a plectonemically supercoiled circular DNA and by incorporating chromosome conformation capture based data to generate an ensemble of base pair resolution models consistent with the experimental data. Significant structural variability was found with different degrees of bending and twisting but with overall similar topologies and shapes that are consistent with C...
February 26, 2018: Nucleic Acids Research
Jing Zhang, Jing Li, Li Yang, Chen Yuan, Yi-Quan Zhang, You Song
A family of trigonal antiprismatic Co(II) complexes was synthesized, which exhibited field-induced Raman process dominated single-molecule magnet behavior. Despite the coordination environment of Co(II) being of similar symmetry, the four complexes exhibit distinct dynamic magnetic properties owing to their packing arrangements and dipole-dipole interactions. On the basis of computational results we have demonstrated that the gz and giso values follow a cosine relation with respect to the rotated angle φ (twist angle φ defined as the rotation angle of one coordination square away from the eclipse conformation to the other)...
March 12, 2018: Inorganic Chemistry
Emily E Pocock, Richard J Mandle, John W Goodby
Liquid crystalline phases with a spontaneous twist-bend modulation are most commonly observed for dimers and bimesogens with nonamethylene spacers. In order to redress this balance we devised a simple chemical intermediate that can be used to prepare unsymmetrical bimesogens; as a proof of concept we prepared and studied eleven novel materials with all found to exhibit the twist-bend phase and exhibit a linear relationship between TN-I and TTB-N. A computational study of the conformational landscape reveals the octamethyleneoxy spacer to have a broader distribution of bend-angles than the nonamethylene equivalent, leading to reductions in the thermal stability of the TB phase...
March 12, 2018: Soft Matter
Clothilde Philouze, Philippe Obert, Stéphane Nottin, Asma Benamor, Olivier Barthez, Falah Aboukhoudir
BACKGROUND: Discrepancies are present in the literature on resting myocardial mechanics in patients with uncomplicated type 2 diabetes mellitus (T2DM). Data are noticeably sparse regarding circumferential function and torsional mechanics. Resting deformation imaging may not be sensitive enough to detect subtle dysfunctions. The aim of this study was thus to comprehensively evaluate myocardial mechanics in patients with T2DM at rest and to investigate whether dobutamine stress echocardiography could unmask functional alterations that would remain otherwise subtle at rest...
March 8, 2018: Journal of the American Society of Echocardiography
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"