Search results for "Pyramid"
showing 10 items of 410 documents
Structural characterisation and nuclease activity of mixed copper(II) complexes with sulfonamides and bipyridil
2003
Mixed copper complexes have been synthetised through reaction of Cu(II) salts with bipyridil and N-quinolin-8-yl-p-toluenesulfonamide (Hqtsa), N-quinolin-8-yl-benzenesulfonamide (Hqbsa) or N-quinolin-8-yl-naftalenesulfonamide (Hqnsa). Single crystal X-ray diffraction structure determination shows that copper cations are five-coordinated, one complex have distorted bipyramidal trigonal geometry and the other have a distorted square-pyramid. The FT IR and EPR spectra are also reported. Electrophoresis results show that the synthetised complexes in the presence of ascorbate and hydrogen peroxide are chemical nucleases.
Synthesis, characterization, and in vitro antimicrobial activity of organotin(IV) complexes with triazolo-pyrimidine ligands containing exocyclic oxy…
2005
Abstract Tri-organotin(IV) complexes of the triazolo-pyrimidine derivatives 4,5-dihydro-5-oxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (5HtpO), 4,7-dihydro-5-methyl-7-oxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (HmtpO), and 4,5,6,7-tetrahydro-5,7-dioxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (H 2 tpO 2 ), and the diorganotin derivative n -Bu 2 Sn(tpO 2 ), were synthesized and characterized by means of infrared and 119 Sn Mossbauer spectroscopy. In all the complexes obtained the triazolopyrimidines act as multidentate ligands producing polymeric structures. A trigonal bipyramidal arrangement of the ligands around the tin atom is proposed for triorganotin(IV) derivatives, with organic groups on the equatoria…
Structural investigations on diorgano- and triorganotin(IV) derivatives of [meso-tetra(4-sulfonatophenyl)porphine]metal chlorides.
2006
Abstract Several new complexes of organotin(IV) moieties with MCln[meso-tetra(4-sulfonatophenyl)porphine], (R2Sn)2MCln[meso-tetra(4-sulfonatophenyl)-porphinate]s and (R3Sn)4MCln [meso-tetra(4-sulfonatophenyl)porphinate]s, [M = Fe(III), Mn(III): n = 1, R = Me, n-Bu; Ph; M = Sn(IV): n = 2, R = Me, n-Bu] have been synthesized and their solid state configuration investigated by infrared (IR) and Mossbauer spectroscopy, and by 1H and 13C NMR in D2O. The electron density on the metal ion coordinated inside the porphyrin ring is not influenced by the organotin(IV) moieties bonded to the oxygen atoms of the side chain sulfonatophenyl groups, as it has been inferred on the basis of Mossbauer spectro…
Metal Telluride Clusters Composed of Niobocene Carbonyl, Telluride, and Cobalt Carbonyl Units: Syntheses, Structures, and Reactivity
2000
Abstract: The reaction of [Cp#2NbTe2H] (1#; Cp# = Cp* (C5Me5) or Cp(x) (C5Me4Et)) with two equivalents of [Co2(CO)8] gives a series of cobalt carbonyl telluride clusters that contain different types of niobocene carbonyl fragments. At 0 degrees C, [Cp#2NbTe2CO3(CO)7] (2#) and [Co4Te2(CO)10] (3) are formed which disappear at higher temperatures: in boiling toluene a mixture of [cat2][Co9Te6(CO)8] (5#) (cat= [Cp#2Nb(CO)2]+) and [cat2][Co11Te7(CO)10] (6#) is formed along with [cat][Co(CO)4] (4#). Complexes 6# transform into [cat][Co11Te7(CO)10] (7#) upon interaction with HPF6 or wet SiO2. The molecular structures of 2(Cp(x)), 4(Cp(x)), 5(Cp*), 6(Cp*) and 7(Cp*) have been determined by X-ray cr…
Low Level Languages for the PAPIA Machine
1986
The paper presents the low-level languages implemented up to date to program the PAPIA machine. The parallel assembly-level P-MAGRO package, the microcode level instruction set and a machine simulating environment are described.
Synthesis, structure and magnetic properties of the one-dimensional chain compound {K[Fe(1,3,5-triazine-2,4,6-tricarboxylate)(H2O)2]·2H2O}∞
2002
The one-dimensional chain compound {[Fe(1,3,5-triazine-2,4,6-tricarboxylate)(H2O)2]}n−n was obtained from a reaction of 1,3,5-triazine-2,4,6-tricarboxylate with Fe(II) in water at room temperature. The high-spin Fe(II) centers adopt a pentagonal bipyramid geometry with unusual ligand binding modes. Magnetic measurements revealed weak magnetic interactions between paramagnetic centers; these were modeled with both axial and rhombic distortions.
Alterations in membrane and firing properties of layer 2/3 pyramidal neurons following focal laser lesions in rat visual cortex.
2013
Focal cortical injuries are well known to cause changes in function and excitability of the surviving cortical areas but the cellular correlates of these physiological alterations are not fully understood. In the present study we employed a well established ex vivo-in vitro model of focal laser lesions in the rat visual cortex and we studied membrane and firing properties of the surviving layer 2/3 pyramidal neurons. Patch-clamp recordings, performed in the first week post-injury, revealed an increased input resistance, a depolarized spike threshold as well as alterations in the firing pattern of neurons in the cortex ipsilateral to the lesion. Notably, the reported lesion-induced alteratio…
Modelling the spatial and temporal constrains of the GABAergic influence on neuronal excitability
2021
GABA (γ-amino butyric acid) is an inhibitory neurotransmitter in the adult brain that can mediate depolarizing responses during development or after neuropathological insults. Under which conditions GABAergic membrane depolarizations are sufficient to impose excitatory effects is hard to predict, as shunting inhibition and GABAergic effects on spatiotemporal filtering of excitatory inputs must be considered. To evaluate at which reversal potential a net excitatory effect was imposed by GABA (EGABAThr), we performed a detailed in-silico study using simple neuronal topologies and distinct spatiotemporal relations between GABAergic and glutamatergic inputs. These simulations revealed for GABAe…
Development and Practical Use of a Medical Vocabulary-Thesaurus-Dictionary for Patient Empowerment
2018
Health empowerment can be obtained through an informative and educational intervention to increase one's ability to think critically and act autonomously. Medical texts are usually written by professionals and can be difficulty understood by non experts who do not have the same skills and vocabularies. Thus, it would be desirable to have an online medical vocabulary-thesaurus-dictionary that can help a non expert to easily find the consumer equivalent of medical (technical) terms and additional consumer information. To this end, we have developed an online multilingual medical vocabulary-thesaurus-dictionary by interconnecting different online sources, i.e., medical vocabularies to create a…
Crystal polymorphism of (μ4–O)-body centered adamantanoid Cu(II) complexes
2016
Abstract Two novel polymorphs of [Cu4(μ4–O)(μ–Cl)6(DASO)4], (DASO = diallyl sulfoxide; C6H10OS), rhombic (C) and triclinic (D), were obtained and examined by single crystal X-ray diffraction analysis at two temperatures, 295(2) and 100(1) K. This study, in addition to our recent work on the tetragonal (A) and trigonal (B) forms of the title compound, allowed determining the nature of polymorphism and temperature-induced phase transitions. It is stated that both the packing arrangement and the displacive transformation integrate these structures, forming the symmetrically and thermodynamically related series: A,B → C → D. The C3h → C4 distortion of Cu(II) trigonal bipyramidal coordination ge…