Search results for "Ordination"

Mice lacking Plexin-B3 display normal CNS morphology and behaviour

2009

Semaphorins and their receptors, plexins, have emerged as important regulators of a multitude of biological processes. Plexin-B3 has been shown to be selectively expressed in postnatal oligodendrocytes. In contrast to the well-characterized Plexin-A family and the Plexin-B family members Plexin-B1 and -B2, no data are available on the functional role of Plexin-B3 in the central nervous system in vivo. Here we have elucidated the functional significance of Plexin-B3 by generating and analyzing constitutive knock-out mice. Plexin-B3-deficient mice were found to be viable and fertile. A systematic histological analysis revealed no morphological defects in the brain or spinal cord of mutant ani…

Cerebellum and Prematurity: A Complex Interplay Between Disruptive and Dysmaturational Events.

2021

The cerebellum plays a critical regulatory role in motor coordination, cognition, behavior, language, memory, and learning, hence overseeing a multiplicity of functions. Cerebellar development begins during early embryonic development, lasting until the first postnatal years. Particularly, the greatest increase of its volume occurs during the third trimester of pregnancy, which represents a critical period for cerebellar maturation. Preterm birth and all the related prenatal and perinatal contingencies may determine both dysmaturative and lesional events, potentially involving the developing cerebellum, and contributing to the constellation of the neuropsychiatric outcomes with several impl…

A rare example of nickel(ii) chains based on a heteroscorpionate-like ligand with quadruple imidazolyl interactions

2014

The first nickel(ii) complex with the heteroscorpionate-like bridging ligand DIMMAL (2-di1H-2-imidazolylmethylmalonate), [Ni(DIMMAL)(H2O)3]n·3nH2O (1), is a one-dimensional coordination polymer whose structure shows regular Ni(ii) chains with H-bonding inter-chain interactions and a rare example of a Quadruple Imidazolyl Embrace (QIE). The Ni(ii) chain shows a weak antiferromagnetic interaction that can be modelled with a regular S = 1 chain model including a zero field splitting with g = 2.270, J = -1.5 cm(-1) and D = -2.26 cm(-1).

Transition Metal Catalyzed Olefin, Cycloolefin, and Styrene Polymerization

2013

The sections in this article are History and Trends Polymerization Processes Supported Catalysts and Morphology Control Polymerization Mechanisms and Stereoselectivity History and Principles of Metallocene Catalysis Regio- and Stereoselective Polymerization of α-Olefins Polymerization of Cyclic Olefins, Cyclopolymerization, and Stereoselective Polymerization of Styrene Late Transition Metal Catalysts Transition Metal Catalyzed Copolymerization Acknowledgements

New Pressure-Induced Polymorphic Transitions of Anhydrous Magnesium Sulfate

2017

The effects of pressure on the crystal structure of the three known polymorphs of magnesium sulfate have been theoretically study by means of DFT calculations up to 45 GPa. We determined that at ambient conditions gamma MgSO4 is an unstable polymorph, which decompose into MgO and SO3, and that the response of the other two polymorphs to hydrostatic pressure is non isotropic. Additionally we found that at all pressures beta MgSO4 has a largest enthalpy than alpha MgSO4. This indicates that beta MgSO4 is thermodynamically unstable versus alpha MgSO4 and predicts the occurrence of a beta alpha phase transition under moderate compression. Our calculations also predict the existence under pressu…

Dinuclear chloroneodymium quinolinylcarboxylates: The molecular structures affected by water and the catalytic behavior toward isoprene polymerization

2016

Abstract A series of dinuclear chloroneodymium quinolinylcarboxylate compounds was synthesized and characterized. The nature and importance of metal-organic aggregations have been considered as an important factor regarding the molecular structure and catalytic performance. The neodymium center in all the title compounds exhibits the coordination numbers of 8. Cage aggregation was observed in the solid state, and the cyclic arrangement was achieved when water molecules were incorporated into the structure. Upon the activation with Al(i-Bu)3, all the title neodymium compounds form the efficient catalysts for isoprene polymerization. The catalytic activities are not strongly affected by the m…

Hydration of agarose double helix: A monte carlo simulation

2009

The structure of the water around agarose double helix is analyzed with ab initio quantum mechanical calculations and Monte Carlo simulations. The potential surface is sampled by computing the interaction energy between fragments of agarose and a water molecule placed at 221 different orientations and/or positions. These energy values are fitted to a simple analytical expression representing atom-atom pair potentials for a water molecule interacting with agarose. A preliminary understanding of the agarose-water interaction is obtained from isoenergy contour maps at planar cross sections, perpendicular to the long axis of the double helix, and for cylindrical surfaces enclosing the double he…

Alternating Ferro- and Antiferromagnetic Interactions in a Chainlike CuII Coordination Polymer

1993

Coordinating and hydrogen bonding ability of a bifunctional 2D paddle-wheel copper(II) coordination polymer

2015

abstract A new copper(II) complex of formula {[Cu 2 (H 2 btc) 2 (dmf) 2 ] 4dmf} n (1)[H 4 btc = 1,2,4,5-benzenetetracarb-oxylic acid, dmf = dimethylformamide] has been synthesised and its structure determined by X-raydiffraction. The structure displays a new square grid of ‘‘paddle-wheel’’ tetracarboxylate-bridgeddicopper(II) units with an intradimer copper–copper separation of 2.619(2) A. The dmf molecules areretained through weak axial coordinative bonds and hydrogen bonding interactions with the carboxylicgroups of the porous neutral network of 4 4 net topology. The magnetic behaviour of 1 corresponds to astrong antiferromagnetic coupling within each dicopper(II) unit (J = 343 cm 1 with …

Syntheses and crystal structures of three novel Cu(II) coordination polymers of different dimensionality constructed from Cu(II) carboxylates (carbox…

2004

Abstract We herein report three new coordination polymers generated from Cu(II) carboxylates (mal, 2ac, fum) and conformationally flexible bifunctional IX as building blocks. All the three complexes adopt unique structures in the solid state. The complex [Cu2(mal)2(IX)2(H2O)6]n crystallizes as orthorhombic co-linear rods with space group P2(1) P2(1) P2(1). Each rod is further formed of two tightly intertwined strings. The second polymer [Cu2(ac)4(IX)2]n crystallizes with space group P1 which consists of two sets of intersecting 2D sheets composed of parallel rods which interpenetrate to form a fully interlocked 3D structure. In both these complexes IX coordinates in the anti mode. The third…