6,742 research outputs found
Order-disorder (OD) structures of Rb₂Zn(TeO₃)(CO₃)·H₂O and Na₂Zn₂Te₄O₁₁
No full textSingle crystals of the two alkali metal zinc oxidotellurates(IV), Rb₂Zn(TeO₃)(CO₃)·H₂O and Na₂Zn₂Te₄O₁₁, were obtained by reactions of mixtures of ZnO, TeO₂, Rb₂CO₃ (molar ratios 2:3:6) and ZnO, TeO₂, Na₂CO₃ (molar ratios 2:3:10), respectively, with small amounts of water as a mineralizer. Both compounds crystallize as order-disorder (OD) structures of layers and feature a high stacking fault probability. The crystal structure of Rb₂Zn(TeO₃)(CO₃)·H₂O is composed of layers extending parallel to (100). The structure is composed of two kinds of non-polar OD layers consisting of trigonal-pyramidal [TeO₃]2-, tetrahedral [ZnO₄]6-, Rb1+, and CO₃2-, H₂O, Rb2+, respectively. Different centrings of the layer groups lead to an ambiguity in the stacking arrangement. The crystal structure of Na₂Zn₂Te₄O₁₁ is built from layers extending parallel to (001). Trigonal-pyramidal [TeO₃]2- and bisphenoidal [TeO₄]4- polyhedra form [Te₄O₁₁]6- groups, which are connected by longer Te-O-contacts to form 1∞[Te₈O₂₂]12- double chains oriented along either [100] or [010]. These chains form non-polar layers, which appear alternatingly in two orientations related by a fourfold rotoinversion. The Zn2+ and Na+ cations are located at the layer interface. The stacking ambiguity is due to different lattices of adjacent layers
Teo Hernandez « Fragments dispersés de mémoire et de rêve »
No full textA l'occasion de l'exposition présentée à l'Instituto cultural de Mexico 4 avril - 31 mai 2019 AU STUDIO DES URSULINES (Cinéma) « Scratch Projection», Ligth Cone, mardi 9 avril, 20 h Sélection de films du collectif MétroBarbèsRochechou’Art Gaël Badaud, Teo Hernandez, Jakobois, Michel Nedjar Billet 8,50 €, tarif réduit 6,80 € AU CENTRE POMPIDOU Exposition, à partir du 10 avril 2019 Ouverture d’une salle dédiée aux films « graphiques » de Teo Hernandez au Musée National d’art mo..
Hydrothermal synthesis of Ni₃TeO₆ and Cu₃TeO₆ nanostructures for magnetic and photoconductivity applications
No full textAbstract
Despite great attention toward transition metal tellurates especially M₃TeO₆ (M = transition metal) in magnetoelectric applications, control on single phasic morphology-oriented growth of these tellurates at the nanoscale is still missing. Herein, a hydrothermal synthesis is performed to synthesize single-phased nanocrystals of two metal tellurates, i.e., Ni₃TeO₆ (NTO with average particle size ∼37 nm) and Cu₃TeO₆ (CTO ∼ 140 nm), using NaOH as an additive. This method favors the synthesis of pure NTO and CTO nanoparticles without the incorporation of Na at pH = 7 in MTO crystal structures such as Na₂M₂TeO₆, as it happens in conventional synthesis approaches such as solid-state reaction and/or coprecipitation. Systematic characterization techniques utilizing in-house and synchrotron-based characterization methods for the morphological, structural, electronic, magnetic, and photoconductivity properties of nanomaterials showed the absence of Na in individual particulate single-phase MTO nanocrystals. Prepared MTO nanocrystals also exhibit slightly higher antiferromagnetic interactions (e.g., TN-NTO = 57 K and TN-CTO = 68 K) compared to previously reported MTO single crystals. Interestingly, NTO and CTO show not only a semiconducting nature but also photoconductivity. The proposed design scheme opens the door to any metal tellurates for controllable synthesis toward different applications. Moreover, the photoconductivity results of MTO nanomaterials prepared serve as a preliminary proof of concept for potential application as photodetectors
Mg(H₂O)₂[TeO₂(OH)₄]: a polytypic structure with a two-mode disordered stacking arrangement
No full textCrystals of the hydrous magnesium orthotellurate(VI) Mg(H₂O)2[TeO₂(OH)₄] were grown by slow diffusion of an aqueous MgCl₂ solution into a KOH/Te(OH)₆ solution immobilized in gelatin. The crystal structure is built of sheets of nearly regular corner-sharing [MgO₆] and [TeO₆] octahedra. Half of the bridging O atoms are connected to disordered H atoms, which are located in rhomboidal voids (long and short diameters of ~5.0 and ~2.5 Å, respectively) of these layers. Moreover, the Teⱽᴵ atom connects to two OH⁻ ions and the Mgᴵᴵ atom to two H₂O molecules. The OH⁻ ions and H₂O molecules connect adjacent layers forming a disordered hydrogen-bonding network. In a given layer, an adjacent layer may be positioned in four ways, which can be characterized by one of two origin shifts and one of two orientations with respect to [100]. The crystals feature a disordered stacking arrangement, leading to rods of diffuse scattering in the diffraction pattern. The polytypism is explained by application of the order-disorder (OD) theory. Different refinement models are compared and the diffuse scattering is evaluated with structure factor calculations. The correlation coefficient of subsequent origin shifts is ~ -0.33, whereas the orientation of the layers is essentially random. Determining the latter is particularly difficult owing to a small contribution to the diffraction pattern and virtually indistinguishable diffraction patterns for pairs of correlations with the same absolute value. On longer standing in a glass vial, an ordered polytype forms
Album descriptivo del Ejercito y de la Armada
No full textLas h. de lám.: " dibujos de Soria Santa Cruz y Teo Rufflé, cromolitº.
Setting priorities for measures of performance for geriatric medical services
No full textWe undertook a two-round Delphi study of the views of consultant geriatricians in three Health Regions on the relative appropriateness of 12 possible performance measures for geriatric services. We compared geriatricians' responses with those of 44 cognitively-intact day hospital patients. Of 138 geriatricians, 89 responded to the first round postal survey, 84 to the second round. The rank order of geriatricians' suggestions did not change from round one to round two, and there was convergence of opinion with a significant decrease in the coefficients of variation of the ranks (p < 0.05, Wilcoxon Test). Geriatricians and patients gave high priority to 'reducing disability' and 'improving quality of life', and low priority to 'reducing mortality'. Geriatricians gave higher priority than patients to 'consumer satisfaction', 'problem resolution' and 'efficient use of resources'. Patients gave higher priority to 'reducing burden on carers', 'measures of service activity' and 'avoiding institutional care'. The study shows that it is possible to obtain a consensus amongst geriatricians about the priorities for measuring the performance of geriatric medical services. Similarities to and differences from patients' views illustrate the need to engage more than one group in the debate about appropriate measures of performance. Findings in both groups give support to recent attempts to develop and use assessment methods for the measurement of disability and quality of life in clinical practice
Two Theorems on Packings of Graphs
No full textA simple, undirected, loopless graph G of order p and size q is called a (p, q) graph. Two graphs G and H of the same order are packable if G can be embedded in the complement H¯ of H. Two theorems are proved in this paper. Theorem 1 gives a complete characterization of two (p, p − 1) graphs which are packable. Theorem 2 gives a complete characterization of the pairs {T, G}, where T is a tree of order p and G is a (p, p) graph, that can be packed. Theorem 1 generalizes some earlier results of N. Sauer and J. Spencer, D. Burns and S. Schuster, and P. J. Slater, S. K. Teo and H. P. Yap. Theorem 2 extends an earlier result of P. J. Slater, S. K. Teo and H. P. Yap
Comparison of Transanal Minimally Invasive Surgery (tamis) and Transanal Endoscopic Operations (teo)
No full textRectal lesions, benign or malignant, are one of the most encountered clinical entities in general surgery departments.
Technological breakthroughs in local excision techniques have been occurring such as transanal endoscopic microsurgery
(TEM), transanal minimally invasive surgery (TAMIS), and transanal endoscopic operations (TEO) during the last two decades.
We compared the results between TAMIS and TEO for removing rectal lesions. The study was conducted on patients who
underwent TAMIS and TEO interventions due to rectal lesions between 2010 and 2015 in the Department of General Surgery of
Gulhane Military Medical Academy and the University of Ankara. The data for these patients relating to their age, gender,
distance from the anal verge, operation time, occurrence of first bowel movement after surgery, initiation of oral intake after
surgery, length of hospital stay, tumor size, follow-up, complications, free resection margin, recurrence, postoperative Fecal
Incontinence Severity Index (FISI) and visual analog scale (VAS) scores, and pathologic specimen examination were taken from
the hospital’s electronic database. All data were enrolled and analyzed statistically. The TAMIS group had 23 (54.8%) patients,
and the TEO group had 19 (45.2%) patients. The TAMIS operation time was significantly longer than that of TEO (Z = 3.188;
P 0.001). Median time to first bowel movement in the TAMIS group was 36.0 h (interquartile range (IQR) = 12.0) vs. 24.0 h
(IQR = 18.0) in the TEO group; the difference was significant (Z = 3.358; P = 0.001). No significant differences were found
between the two groups in complication rate, recurrence, visual analog scale, or Fecal Incontinence Severity Index. TAMIS and
TEO techniques have been found to produce almost similar results. These two techniques are considered to be good alternatives
to conservative treatment methods with their reliability and feasibility in experienced hands for selected patients. For TAMIS and
TEO techniques to qualify as “treatment of choice,” prospective randomized clinical trials are needed
Interpretasi aksi teo-ecology dan transendentalisme terhadap pelestarian lingkungan
No full textThis research presents a reading of the aspects of religious transidentalism in presenting the narrative of environmental preservation. Certainly in that context, the author tries to illustrate with teo-ecology construction based on quranic insights. Therefore, man as a subject, occupies a wide space in realizing the idea of godliness and humanistics in managing the nature and environment that God has given. Result of this study provides a major argument against the meaning of the Quran as the basis of environmental Teo-Ecology which contributes the deepest contribution, so that environmental preservation is always encouraged. In addition, in environmental preservation is necessary also the construction of ecological ethics humanizes the environment itself, so that a balance arises there. Lastly, it is no less important to elicit an attitude of transcendentalism in man that as god's representative on Earth must have mentally managed the environment well
The modular organization of projections from areas V1 and V2 to areas V4 and TEO in macaques
No full textIn addition to the major anatomical pathways from V1 into the temporal lobe, there are other smaller, “bypass” routes that are poorly understood. To investigate the direct projection from V1 to V4 (bypassing V2) and from V2 to TEO (bypassing V4), we injected the foveal and parafoveal representations of V4 and TEO with different retrograde tracers in five hemispheres of four macaques and analyzed the distributions of labeled neurons in V1 and V2 using flattened preparations of the cortex. In V1, labeled neurons were seen after injections in V4 but not TEO. The V4-projecting neurons were located in the foveal representation of V1, in both cytochrome oxidase (CO)-rich blobs and CO-poor interblob regions. In V2, TEO-projecting neurons were intermingled with V4-projecting neurons, although the former were far sparser than the latter. Across the cases, 6–19% of the TEO-projecting neurons were double labeled, that is, also projected to area V4. Both V4- and TEO-projecting neurons formed bands that ran orthogonal to the V1/V2 border, and both were located in CO-rich thin stripes and CO-poor interstripe regions. In some cases, a continuous band of V4-projecting neurons was also found along the V1/V2 border in the foveal representation of V2. The results indicate that the pathways from V1 to V4 and from V2 to TEO involve anatomical subcompartments thought to be concerned with both color and form. These “bypass” routes may allow coarse information about color and form to arrive rapidly in the temporal lobe. The bypass route from V2 to TEO might explain the partial sparing of color and form vision that is seen after lesions of V4. By analogy, given the bypass route from the foveal representation of V1 to V4, lesions of V2 affecting the foveal visual field would also be insufficient to block color and form vision.</jats:p
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