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Valeria Fascianelli, Satoshi Tsujimoto, Encarni Marcos, Aldo Genovesio
In previous work, we studied the activity of neurons in the dorsolateral (PFdl), orbital (PFo), and polar (PFp) prefrontal cortex while monkeys performed a strategy task with 2 spatial goals. A cue instructed 1 of 2 strategies in each trial: stay with the previous goal or shift to the alternative goal. Each trial started with a fixation period, followed by a cue. Subsequently, a delay period was followed by a "go" signal that instructed the monkeys to choose one goal. After each choice, feedback was provided...
December 8, 2017: Cerebral Cortex
Tianyu Zhu, Piotr de Silva, Troy Van Voorhis
Chemical bonding plays a central role in the description and understanding of chemistry. Many methods have been proposed to extract information about bonding from quantum chemical calculations, majority of them resorting to molecular orbitals as basic descriptors. Here, we present a method called Self-Attractive Hartree (SAH) decomposition, to unravel pairs of electrons directly from electron density, which unlike molecular orbitals, is a well defined observable that can be accessed experimentally. The key idea is to partition the density into a sum of one-electron fragments which simultaneously maximize self-repulsion and maintain regular shapes...
December 11, 2017: Journal of Chemical Theory and Computation
Adam R Luxon, Natalie Orms, René P F Kanters, Anna I Krylov, Carol A Parish
The Bergman cyclization is an important reaction in which an enediyne cyclizes to produce a highly reactive diradical species, p-benzyne. Enediyne motifs are found in natural antitumor antibiotic compounds, such as calicheammicin and dynemicin. Understanding the energetics of cyclization is required in order to better control the initiation of the cyclization, which induces cell death. We computed the singlet and triplet potential energy surfaces for the Bergman cyclization of (Z)-hex-3-ene-1,5-diyne using the CCSD and EOM-SF-CCSD methods...
December 11, 2017: Journal of Physical Chemistry. A
Bo Le Chen, Wei Guo Sun, Xiao Yu Kuang, Cheng Lu, Xin Xin Xia, Hong Xiao Shi, George Maroulis
Transition-metal (TM)-doped boron clusters have received considerable attention in recent years, in part, because of their remarkable size-dependent structural and electronic properties. However, the structures of medium-sized boron clusters doped with TM atoms are still not well-known because of the much increased complexity of the potential surface as well as the rapid increase in the number of low-energy isomers, which are the challenges in cluster structural searches. Here, by means of an unbiased structure search, we systematically investigated the structural evolution of medium-sized tantalum-doped boron clusters, TaBn0/- (n = 10-20)...
December 11, 2017: Inorganic Chemistry
Bo Rao, Tong Zhao, Sha Yang, Jinsong Chai, Yiting Pan, Shiyin Weng, Haizhu Yu, Xiaowu Li, Manzhou Zhu
A novel Au36-xCux(m-MBT)24 (x = 1-3, m-MBT = 3-methylbenzenethiolate) nanocluster has been prepared. According to the X-ray single crystal diffractometer, the structure of Au36-xCux(m-MBT)24 is similar to that of Au36(SPhtBu)24. The Au36-xCux(m-MBT)24 nanocluster contains a face-centered cubic (FCC) M28 core, which is protected by 4 M2S3 (M = Au/Cu) staple motifs and 12 bridging SR ligands. The Cu dopants could possibly occupy 14 sites (six in the sub-surface and eight in the staple motifs). Spectral monitoring indicates that the number of Cu dopants sequentially increased on increasing the amount of Cu precursors (relative to a Au control)...
December 11, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Sumit Ganguly, Jeanet Conradie, Jesper Bendix, Kevin J Gagnon, Laura J McCormick, Abhik Ghosh
Two sets of complexes of Co-triarylcorrole-bispyridine complexes, Co[TpXPC](py)2 and Co[Br8TpXPC](py)2 have been synthesized, where TpXPC refers to a meso-tris(para-X-phenyl)corrole ligand with X = CF3, H, Me, and OMe and Br8TpXPC to the corresponding β-octabrominated ligand. The axial pyridines in these complexes were found to be labile and, in dilute solutions in dichloromethane, the complexes dissociate almost completely to the five-coordinate monopyridine complexes. Upon addition of a small quantity of pyridine, the complexes revert back to the six-coordinate forms...
December 11, 2017: Journal of Physical Chemistry. A
Allison S Hacker, Mauricio Pavano, James E Wood, Chad E Immoos, Hannah Hashimoto, Sam P Genis, Derik K Frantz
The [2,1-a]- and [1,2-a]-isomers of fluorenofluorenedione have been synthesized via intramolecular Friedel-Crafts acylations. DFT calculations indicate that the [1,2-a]-isomer adopts a twisted, helical C2-symmetric structure and that its protonated form is the thermodynamic product of the Friedel-Crafts acylation in hot sulfuric acid. Absorption spectroscopy and cyclic voltammetry measurements provide experimental estimations of frontier molecular orbital energy levels, which are reported and discussed.
December 11, 2017: Journal of Organic Chemistry
M Shaheeda, S C Lam, N Cy Chan, H Kl Yuen
No abstract text is available yet for this article.
December 2017: Hong Kong Medical Journal, Xianggang Yi Xue za Zhi
Retno Wahyu Nurhayati, Yoshihiro Ojima, Takeaki Dohda, Masahiro Kino-Oka
The increasing application of regenerative medicine has generated a growing demand for stem cells and their derivatives. Single-use bioreactors offer an attractive platform for stem cell expansion owing to their scalability for large-scale production and feasibility of meeting clinical-grade standards. The current work evaluated the capacity of a single-use bioreactor system (1 L working volume) for expanding Meg01 cells, a megakaryocytic (MK) progenitor cell line. Oxygen supply was provided by surface aeration to minimize foaming and orbital shaking was used to promote oxygen transfer...
December 11, 2017: Biotechnology Progress
Sudip Pan, Susmita Kar, Ranajit Saha, Edison Osorio, Ximena Zarate, Lili Zhao, Gabriel Merino, Pratim K Chattaraj
The viability of noble gas axled boron nanowheel, NgnMB10- (Ng = Ar-Rn, M = Nb, Ta; n = 1, 2), is explored via ab initio computations. In the resulting Ng2-M complexes, the Ng-M-Ng nanorod passes through the center of B10- ring, providing them with an inverse sandwich like structure. While in single Ng bound analogue, the Ng binding enthalpy (Hb) at 298 K ranges from 2.5 to 10.6 kcal/mol, in two Ng bound cases it becomes very low for Ng2MB10- -> Ng + NgMB10- dissociation channel, except for Rn case. For a given Ng, Ta has slightly higher Ng binding ability than Nb...
December 11, 2017: Chemistry: a European Journal
Kang-Jae Shin, Hyun Jin Shin, Shin-Hyo Lee, Ki-Seok Koh, Wu-Chul Song
PURPOSE: To investigate the topographical relationship between the frontal branch of the superficial temporal artery (FSTA) and the temporal branch of the facial nerve (TFN) with the aim of preventing nerve injury during FSTA biopsy. METHODS: Fifty-seven hemifaces of 33 cadavers were dissected. Vertical lines drawn to the lateral orbital margin (LOM) and the superior root of the helix were used as the anterior and posterior reference positions, respectively. Horizontal lines drawn through the supraorbital margin and lateral canthus were used as the superior and inferior reference points, respectively...
December 11, 2017: Clinical Anatomy
Shailima Rampogu, Ayoung Baek, Minky Son, Amir Zeb, Chanin Park, Raj Kumar, Gihwan Lee, Donghwan Kim, Yeonuk Choi, Yeongrae Cho, Yohan Park, Seok Ju Park, Keun Woo Lee
Progeria is a rare genetic disorder characterized by premature aging that eventually leads to death and is noticed globally. Despite alarming conditions, this disease lacks effective medications; however, the farnesyltransferase inhibitors (FTIs) are a hope in the dark. Therefore, the objective of the present article is to identify new compounds from the databases employing pharmacophore based virtual screening. Utilizing nine training set compounds along with lonafarnib, a common feature pharmacophore was constructed consisting of four features...
2017: BioMed Research International
Mark A Wolters, C B Dean
Remote sensing images from Earth-orbiting satellites are a potentially rich data source for monitoring and cataloguing atmospheric health hazards that cover large geographic regions. A method is proposed for classifying such images into hazard and nonhazard regions using the autologistic regression model, which may be viewed as a spatial extension of logistic regression. The method includes a novel and simple approach to parameter estimation that makes it well suited to handling the large and high-dimensional datasets arising from satellite-borne instruments...
2017: Statistics in Biosciences
Koray Sayin, Ayhan Üngördü
Computational investigations were performed for 1,3,7-trimethylpurine-2,6-dione, 3,7-dimethylpurine-2,6-dione, their Ru(II) and Os(III) complexes. B3LYP/6-311++G(d,p)(LANL2DZ) level was used in numerical calculations. Geometric parameters, IR spectrum, 1H-, 13C and 15N NMR spectrum were examined in detail. Additionally, contour diagram of frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) maps, MEP contour and some quantum chemical descriptors were used in the determination of reactivity rankings and active sites...
December 6, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Benjamin A Steinberg, Haiyan Gao, Peter Shrader, Karen Pieper, Laine Thomas, A John Camm, Michael D Ezekowitz, Gregg C Fonarow, Bernard J Gersh, Samuel Goldhaber, Sylvia Haas, Werner Hacke, Peter R Kowey, Jack Ansell, Kenneth W Mahaffey, Gerald Naccarelli, James A Reiffel, Alexander Turpie, Freek Verheugt, Jonathan P Piccini, Ajay Kakkar, Eric D Peterson, Keith A A Fox
Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world. We aimed to provide comprehensive data on international patterns of AF stroke prevention treatment. METHODS: Demographics, comorbidities, and stroke risk of the patients in the GARFIELD-AF (n=51,270), ORBIT-AF I (n=10,132), and ORBIT-AF II (n=11,602) registries were compared (overall N=73,004 from 35 countries). Stroke prevention therapies were assessed among patients with new-onset AF (≤6 weeks). RESULTS: Patients from GARFIELD-AF were less likely to be white (63% vs 89% for ORBIT-AF I and 86% for ORBIT-AF II) or have coronary artery disease (19% vs 36% and 27%), but had similar stroke risk (85% CHA2DS2-VASc ≥2 vs 91% and 85%) and lower bleeding risk (11% with HAS-BLED ≥3 vs 24% and 15%)...
December 2017: American Heart Journal
Huiyu Dong, Zhimin Qiang, Shaogang Liu, Jin Li, Jianwei Yu, Jiuhui Qu
Presence of iodinated X-ray contrast media (ICMs) in source water is of high concern, because of their potential to form highly toxic iodinated disinfection by-products (I-DBPs). This study investigated kinetics, mechanisms and products for oxidation of one ICMs, iopamidol (IPM) by ferrate (Fe(VI)). The obtained apparent second-order rate constants for oxidation of IPM by Fe(VI) ranged from 0.7 M-1 s-1 to 74.6 M-1 s-1 at pH 6.0-10.0, which were highly dependent on pH. It was found that the oxidation of IPM by Fe(VI) led to the formation of highly toxic I-DBPs...
December 5, 2017: Water Research
Qing-Qing Zhang, Chuan-Lu Yang, Mei-Shan Wang, Xiao-Guang Ma, Wen-Wang Liu
The potential energy curves and transition dipole moments of 12Σ+ and 12Π states of GaH+ and InH+ cations are performed by employing ab initio calculations. Based on the potential energy curves, the rotational and vibrational energy levels of the two states are obtained by solving the Schrödinger equation of nuclear movement. The spectroscopic parameters are deduced with the obtained rovibrational energy levels. The spin-orbit coupling effect of the 2Π states for both the GaH+ and InH+ cations are also calculated...
December 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Sophie Charpentier, Luca Galletti, Gunta Kunakova, Riccardo Arpaia, Yuxin Song, Reza Baghdadi, Shu Min Wang, Alexei Kalaboukhov, Eva Olsson, Francesco Tafuri, Dmitry Golubev, Jacob Linder, Thilo Bauch, Floriana Lombardi
Topological superconductivity is central to a variety of novel phenomena involving the interplay between topologically ordered phases and broken-symmetry states. The key ingredient is an unconventional order parameter, with an orbital component containing a chiral p x  + ip y wave term. Here we present phase-sensitive measurements, based on the quantum interference in nanoscale Josephson junctions, realized by using Bi2Te3 topological insulator. We demonstrate that the induced superconductivity is unconventional and consistent with a sign-changing order parameter, such as a chiral p x  + ip y component...
December 8, 2017: Nature Communications
B Visser, M Beck, P Bornhauser, G Knopp, J A van Bokhoven, R Marquardt, C Gourlaouen, P P Radi
The low energy electronic structure of the copper dimer has been re-investigated using non-linear four-wave mixing spectroscopy and high level ab initio calculations. In addition to the measurement of the previously reported A, B, and C electronic states, a new state denoted A' is identified with T0 = 20 100.4090(16) cm-1 (63Cu2). Rotational analysis of the A'-X (0,0) and (1,0) transitions leads to the assignment of A' 1u. Ab initio calculations present the first theoretical description of the low energy states of the copper dimer in Hund's case (c) and confirm the experimental assignment...
December 7, 2017: Journal of Chemical Physics
Lingyuan Gao, Jaime Souto-Casares, James R Chelikowsky, Alexander A Demkov
Work function values measured at different surfaces of a metal are usually different. This raises an interesting question: What is the work function of a nano-size crystal, where differently oriented facets can be adjacent? Work functions of metallic nanocrystals are also of significant practical interest, especially in catalytic applications. Using real space pseudopotentials constructed within density functional theory, we compute the local work function of large aluminum and gold nanocrystals. We investigate how the local work function follows the change of the surface plane orientation around multifaceted nanocrystals, and we establish the importance of the orbital character near the Fermi level in determining work function differences between facets...
December 7, 2017: Journal of Chemical Physics
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