Read by QxMD icon Read


Xiaochun Liu, Hang Yin, Hui Li, Ying Shi
DFT and TDDFT methods were carried out to investigate the influences of intramolecular and intermolecular hydrogen bonding on excited state charge transfer for coumarin 343 (C343). Intramolecular hydrogen bonding is formed between carboxylic acid group and carbonyl group in C343 monomer. However, in dimethylsulfoxide (DMSO) solution, DMSO 'opens up' the intramolecular hydrogen bonding and forms solute-solvent intermolecular hydrogen bonded C343-DMSO complex. Analysis of frontier molecular orbitals reveals that intramolecular charge transfer (ICT) occurs in the first excited state both for C343 monomer and complex...
January 12, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Jimil George, Hun Young Kim, Kyungsoo Oh
The facile synthesis of 6- to 8-membered pyrrololactams has been developed using a ring expansion of spiro-2H-pyrroles, the products of intermolecular alkyne-isocyanide click reactions. The key to successful ring expansion of spiro-2H-pyrroles to pyrrololactams is the enforced orbital overlap between the internal alkene and the amide carbonyl group through the conformationally locked bicyclic structures. The newly disclosed α-isocyano lactams, substrates for click reactions, should find their utility in the synthesis of pharmaceutically important heterocyclic compounds...
January 20, 2017: Organic Letters
M K Yang, N Kim, H-K Choung, S I Khwarg
PurposeTo report long-term outcome of new surgical technique for prolapsed subconjunctival orbital fat.Patients and methodsRetrospective study was conducted on 48 eyes of 37 patients who underwent excision of prolapsed subconjunctival orbital fat with conjunctival fixation to the sclera. Complications and recurrence were evaluated.ResultsThe mean follow-up period was 39 months (range, 8-101 months). Two eyes (4.4%) developed recurrence at 4 and 8 years after surgery. No long-term complication was found.ConclusionsThe new surgical technique to manage prolapsed subconjunctival orbital fat using conjunctival fixation to the sclera was very useful and effective, with few recurrence and no long-term complication...
January 20, 2017: Eye
Seunghwan Hong, Yoonjo Choi, Ilsuk Park, Hong-Gyoo Sohn
Geometric correction of SAR satellite imagery is the process to adjust the model parameters that define the relationship between ground and image coordinates. To achieve sub-pixel geolocation accuracy, the adoption of the appropriate geometric correction model and parameters is important. Until now, various geometric correction models have been developed and applied. However, it is still difficult for general users to adopt a suitable geometric correction models having sufficient precision. In this regard, this paper evaluated the orbit-based and time-offset-based models with an error simulation...
January 17, 2017: Sensors
Motohiko Suzuki, Yoshihisa Nakamura, Shinya Ozaki, Makoto Yokota, Shingo Murakami
OBJECTIVES: Endoscopic approach provides excellent magnification and visualization, and a purely transnasal approach is minimally invasive method. However, it is very difficult to repair anterior and lateral fractures with the previous transnasal endoscopic approaches, since repair of orbital fractures is managed through the middle meatus and ostium from the posterior side of the nasolacrimal duct with side-viewing endoscope and curved instruments. Therefore, the authors used modified transnasal endoscopic approach as an alternative for repair of orbital floor fractures in order to effectively reach the lateral or anterior fracture of the orbital floor with straight endoscope and instruments endoscopically...
January 18, 2017: Journal of Craniofacial Surgery
Nezhat Pournaghavi, Mahdi Esmaeilzadeh, Adib Abrishamifar, Somaieh Ahmadi
Regarding the spin field effect transistor (spin FET) challenges such as mismatch effect in spin injection and insufficient spin life time, we propose a silicene based device which can be a promising candidate to overcome some of those problems. Using non-equilibrium Green���s function method, we investigate the spin-dependent conductance in a zigzag silicene nanoribbon connected to two magnetized leads which are supposed to be either in parallel or anti-parallel configurations. For both configurations, a controllable spin current can be obtained when the Rashba effect is present; thus, we can have a spin filter device...
January 20, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
G Tkachov
Noncentrosymmetric superconductors exhibit the magnetoelectric effect, which manifests itself in the appearance of the magnetic spin polarization in response to a dissipationless electric current (supercurrent). While much attention has been dedicated to the thermodynamic version of this phenomenon (Edelstein effect), nonequilibrium transport magnetoelectric effects have not been explored yet. We propose the magnetoelectric Andreev effect (MAE), which consists in the generation of spin-polarized triplet Andreev conductance by an electric supercurrent...
January 6, 2017: Physical Review Letters
Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Rafal Skolasinski, Michael Wimmer, Binh-Minh Nguyen, Andrey A Kiselev, Wei Yi, Marko Sokolich, Michael J Manfra, Fanming Qu, Arjan J A Beukman, Leo P Kouwenhoven, Charles M Marcus
Transport measurements in inverted InAs/GaSb quantum wells reveal a giant spin-orbit splitting of the energy bands close to the hybridization gap. The splitting results from the interplay of electron-hole mixing and spin-orbit coupling, and can exceed the hybridization gap. We experimentally investigate the band splitting as a function of top gate voltage for both electronlike and holelike states. Unlike conventional, noninverted two-dimensional electron gases, the Fermi energy in InAs/GaSb can cross a single spin-resolved band, resulting in full spin-orbit polarization...
January 6, 2017: Physical Review Letters
Maarten van de Meent
The linear in mass ratio correction to the periapsis advance of equatorial nearly circular orbits around a spinning black hole is calculated for the first time and to a very high precision, providing a key benchmark for different approaches modeling spinning binaries. The high precision of the calculation is leveraged to discriminate between two recent incompatible derivations of the 4 post-Newtonian equations of motion. Finally, the limit of the periapsis advance near the innermost stable orbit (ISCO) allows the determination of the ISCO shift, validating previous calculations using the first law of binary mechanics...
January 6, 2017: Physical Review Letters
Daijiro Nozaki, Andreas Lücke, Wolf Gero Schmidt
Destructive Quantum interference (QI) in molecular junctions has attracted much attention in recent years. It can tune the conductance of molecular devices dramatically, which implies numerous potential applications in thermoelectric and switching applications. There are several schemes that address and rationalize QI in single molecular devices. Dimers play a particular role in this respect, since the QI signal may disappear, depending on the dislocation of monomers. In this Letter, we derive a simple rule that governs the occurrence of QI in weakly coupled dimer stacks of both alternant and non-alternant polyaromatic hydrocarbons (PAHs) and extends the Tada-Yoshizawa scheme...
January 20, 2017: Journal of Physical Chemistry Letters
Xuandi Lai, Lishan Tan, Xiulong Deng, Jinbin Liu, Aiqing Li, Jianyu Liu, Jianqiang Hu
A fluorescence turn-on system for highly efficient and prolonged tumor imaging has been established by Co2+-induced coordination self-assembly strategy, in which luminescent glutathione (GSH)-modified gold nanoparticles (LGAuNPs) are assembled into LGAuNPs assemblies (LGAuNPs-Co) through coordination bond between unoccupied orbit of Co2+ and lone pair electrons of GSH on the surface of LGAuNPs. The LGAuNPs-Co is sensitive to microenvironment pH and its quenched luminescence will be turned on in tumor tissues (acidic microenvironment), which behaves as a fluorescence turn-on system for passive tumor imaging...
January 20, 2017: ACS Applied Materials & Interfaces
Shun-Suke Asami, Shintaro Ishida, Takeaki Iwamoto, Katsunori Suzuki, Makoto Yamashita
Radical anions of a diphosphene with two boryl substituents were isolated and characterized by single-crystal X-ray diffraction, electron spin resonance (ESR), and UV/Vis absorption spectroscopy as well as DFT calculations. Structural analysis of the radical anions revealed an elongation of the P=P bond and a contraction of the B-P bonds relative to the neutral diphosphene. The UV/Vis spectra of these radical anions showed a strong absorption in the visible region, which was assigned to SOMO-related transitions on the basis of DFT calculations...
February 1, 2017: Angewandte Chemie
Jan-Philipp Hanke, Frank Freimuth, Stefan Blügel, Yuriy Mokrousov
We predict from first principles an entirely topological orbital magnetization in the noncoplanar bulk antiferromagnet γ-FeMn originating in the nontrivial topology of the underlying spin structure, without any reference to spin-orbit interaction. Studying the influence of strain, composition ratio, and spin texture on the topological orbital magnetization and the accompanying topological Hall effect, we promote the scalar spin chirality as key mechanism lifting the orbital degeneracy. The system is thus a prototypical topological orbital ferromagnet, the macroscopic orbital magnetization of which is prominent even without spin-orbit coupling...
January 20, 2017: Scientific Reports
Linong Ji, Puhong Zhang, Dongshan Zhu, Xian Li, Jiachao Ji, Juming Lu, Xiaohui Guo, Weiping Jia, Jianping Weng, Yangfeng Wu, Wenying Yang, Dajin Zou, Zhiguang Zhou, Changyu Pan, Yan Gao, Satish K Garg
AIMS: To examine treatment patterns following basal insulin (BI) introduction in type 2 diabetes mellitus (T2DM) patients under real-world conditions across China. MATERIALS AND METHODS: Overall, 18,995 patients inadequately controlled [HbA1c ≥ 53 mmol/mol (7%)] with oral antihyperglycaemic drugs (OADs) and willing to receive BI treatment were registered at 209 hospitals and followed at baseline (visit 1), 3 months (visit 2), and 6 months (visit 3). Type of BI was initiated at physicians' discretion...
January 20, 2017: Diabetes, Obesity & Metabolism
Joachim Yahalom
No abstract text is available yet for this article.
January 19, 2017: Blood
David Waltham
This paper presents statistical estimates for the location and duration of habitable zones (HZs) around stars of different mass. The approach is based upon the assumption that Earth's location, and the Sun's mass, should not be highly atypical of inhabited planets. The results support climate-model-based estimates for the location of the Sun's HZ except models giving a present-day outer-edge beyond 1.64 AU. The statistical approach also demonstrates that there is a habitability issue for stars smaller than 0...
January 2017: Astrobiology
Peter John Cherry, Syed Awais Rouf, Juha Vaara
We present a derivation and computations of the paramagnetic enhancement of the nuclear magnetic resonance (NMR) spin-spin coupling, which may be expressed in terms of the hyperfine coupling (HFC) and (for systems with multiple unpaired electrons) zero-field splitting (ZFS) tensors. This enhancement is formally analogous to the hyperfine contributions to the NMR shielding tensor as formulated by Kurland and McGarvey. The significance of the spin-spin coupling enhancement is demonstrated by using a combination of density-functional theory and correlated ab initio calculations, to determine the HFC and ZFS tensors, respectively, for two paramagnetic 3d metallocenes, a Cr(II)(acac) 2 complex, a Co(II) pyrazolylborate complex, and a lanthanide system, Gd-DOTA...
January 19, 2017: Journal of Chemical Theory and Computation
Michelle C Neary, Gerard Parkin
The molecular structures of CpMo(PMe3)(CO)2H and CpMo(PMe3)2(CO)H have been determined by X-ray diffraction, thereby revealing four-legged piano-stool structures in which the hydride ligand is trans to CO. However, in view of the different nature of the four basal ligands, the geometries of CpMo(PMe3)(CO)2H and CpMo(PMe3)2(CO)H deviate from that of an idealized four-legged piano stool, such that the two ligands that are orthogonal to the trans H-Mo-CO moiety are displaced towards the hydride ligand. While Cp(R)Mo(PMe3)3-x(CO)xH (Cp(R) = Cp, Cp*; x = 1, 2, 3) are catalysts for the release of H2 from formic acid, the carbonyl derivatives, Cp(R)Mo(CO)3H, are also observed to form dinuclear formate compounds, namely, [Cp(R)Mo(μ-O)(μ-O2CH)]2...
January 19, 2017: Inorganic Chemistry
Miroslav Iliaš, Valeria Pershina
Calculations of the first bond dissociation energies (FBDEs) and other molecular properties of M(CO)6, where M = Mo, W, and Sg, have been performed using a variety of nonrelativistic and relativistic methods, such as ZORA-DFT, X2c+AMFI-CCSD(T), and Dirac-Coulomb density functional theory. The aim of the study is to assist experiments on the measurements of the FBDE of Sg(CO)6. We have found that, different from the results published earlier, the metal-CO bond in Sg(CO)6 should be weaker than that in W(CO)6...
January 19, 2017: Inorganic Chemistry
Chengyong Zhong, Yuanping Chen, Yuee Xie, Yi-Yang Sun, Shengbai Zhang
A semi-Dirac semimetal is a material that exhibits linear band dispersion in one direction and quadratic band dispersion in the orthogonal direction and, therefore, hosts massless and massive fermions at the same point in the momentum space. While a number of interesting physical properties have been predicted in semi-Dirac semimetals, it has been rare to realize such materials in condensed matter. Based on the fact that some honeycomb materials are easily oxidized or chemically absorb other atoms, here, we theoretically propose an approach of modifying their band structures by covalent addition of group-VI elements and strain engineering...
January 19, 2017: Physical Chemistry Chemical Physics: PCCP
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"