931 resultados para mimetic desire
Resumo:
This paper describes a novel mimetic technique of using frequency domain approach and digital filters for automatic generation of EEG reports. Digitized EEG data files, transported on a cartridge, have been used for the analysis. The signals are filtered for alpha, beta, theta and delta bands with digital bandpass filters of fourth-order, cascaded, Butterworth, infinite impulse response (IIR) type. The maximum amplitude, mean frequency, continuity index and degree of asymmetry have been computed for a given EEG frequency band. Finally, searches for the presence of artifacts (eye movement or muscle artifacts) in the EEG records have been made.
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We report here the synthesis and characterization of a few phenolate-based ligands bearing tert- amino substituent and their Zn(II) and Cu(II) metal complexes. Three mono/binuclear Zn(II) and Cu(II) complexes Zn(L1)(H2O)].CH3OH.H2O (1) (H (2) L1 = 6,6(')-(((2-dimethylamino)ethylazanediyl)bis(methylene))bis(2, 4-dimethylphenol), Zn-2(L2)(2)] (2) (H (2) L2 = 2,2(')-(((2-dimethylamino)ethyl)azanediyl)bis(methylene)bis(4- methylphenol) and Cu-2(L3)(2).CH2 Cl-2] (3) (H (2) L3 = (6,6(')-(((2-(diethylamino)ethyl)azanediyl)bis(methylene)) bis(methylene))bis(2,4-dimethylphenol) were synthesized by using three symmetrical tetradendate ligands containing N2O2 donor sites. These complexes are characterized by a variety of techniques including; elemental analysis, mass spectrometry, H-1, C-13 NMR spectroscopic and single crystal X-ray analysis. The new complexes have been tested for the phosphotriesterase (PTE) activity with the help of P-31 NMR spectroscopy. The P-31 NMR studies show that mononuclear complex Zn(L1)(H2O)].CH3OH.H2O (1) can hydrolyse the phosphotriester i.e., p-nitrophenyl diphenylphosphate (PNPDPP), more efficiently than the binuclear complexes Zn-2(L2)(2)] (2) and Cu-2(L3)(2).CH2Cl2] (3). The mononuclear Zn(II) complex (1) having one coordinated water molecule exhibits significant PTE activity which may be due to the generation of a Zn(II)-bound hydroxide ion during the hydrolysis reactions in CHES buffer at pH 9.0.
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Three highly stable, hexacoordinated nonoxidovanadium(IV), V-IV(L)(2), complexes (1-3) have been isolated and structurally characterized with tridentate aroylhydrazonates containing ONO donor atoms. All the complexes are stable in the open air in the solid state as well as in solution, a phenomenon rarely observed in nonoxidovanadium(IV) complexes. The complexes have good solubility in organic solvents, permitting electrochemical and various spectroscopic investigations. The existence of nonoxidovanadium(IV) complexes was confirmed by elemental analysis, ESI mass spectroscopy, cyclic voltammetry, EPR, and magnetic susceptibility measurements. X-ray crystallography showed the N3O3 donor set to define a trigonal prismatic geometry in each case. All the complexes show in vitro insulin mimetic activity against insulin responsive L6 myoblast cells, with complex 3 being the most potent, which is comparable to insulin at the complex concentration of 4 mu M, while the others have moderate insulin mimetic activity. In addition, the in vitro antiproliferative activity of complexes 1-3 against the He La cell line was assayed. The cytotoxicity of the complexes is affected by the various functional groups attached to the bezoylhydrazone derivative and 2 showed considerable antiproliferative activity compared to the most commonly used chemotherapeutic drugs.
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Iodothyronine deiodinases are selenoenzymes which regulate the thyroid hormone homeostasis by catalyzing the regioselective deiodination of thyroxine (T4). Synthetic deiodinase mimetics are important not only to understand the mechanism of enzyme catalysis, but also to develop therapeutic agents as abnormal thyroid hormone levels have implications in different diseases, such as hypoxia, myocardial infarction, critical illness, neuronal ischemia, tissue injury, and cancer. Described herein is that the replacement of sulfur/selenium atoms in a series of deiodinase mimetics by tellurium remarkably alters the reactivity as well as regioselectivity toward T4. The tellurium compounds reported in this paper represent the first examples of deiodinase mimetics which mediate sequential deiodination of T4 to produce all the hormone derivatives including T0 under physiologically relevant conditions.
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Organophosphorus-based nerve agents, such as paraoxon, parathion, and malathion, inhibit acetylcholinesterase, which results in paralysis, respiratory failure, and death. Bacteria are known to use the enzyme phosphotriesterase (PTE) to break down these compounds. In this work, we designed vacancy-engineered nanoceria (VE CeO2 NPs) as PTE mimetic hotspots for the rapid degradation of nerve agents. We observed that the hydrolytic effect of the nano-material is due to the synergistic activity between both Ce3+ and Ce4+ ions located in the active site-like hotspots. Furthermore, the catalysis by nanoceria overcomes the product inhibition generally observed for PTE and small molecule-based PTE mimetics.
Resumo:
Organophosphorus-based nerve agents, such as paraoxon, parathion, and malathion, inhibit acetylcholinesterase, which results in paralysis, respiratory failure, and death. Bacteria are known to use the enzyme phosphotriesterase (PTE) to break down these compounds. In this work, we designed vacancy-engineered nanoceria (VE CeO2 NPs) as PTE mimetic hotspots for the rapid degradation of nerve agents. We observed that the hydrolytic effect of the nano-material is due to the synergistic activity between both Ce3+ and Ce4+ ions located in the active site-like hotspots. Furthermore, the catalysis by nanoceria overcomes the product inhibition generally observed for PTE and small molecule-based PTE mimetics.
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Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)
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Nano-fibrillar arrays are fabricated using polystyrene materials. The average diameter of each fiber is about 300 nm. Experiments show that such a fibrillar surface possesses a relatively hydrophobic feature with a water contact angle of 142 degrees. Nanoscale friction properties are mainly focused on. It is found that the friction force of polystyrene nano-fibrillar surfaces is obviously enhanced in contrast to polystyrene smooth surfaces. The apparent coefficient of friction increases with the applied load, but is independent of the scanning speed. An interesting observation is that the friction force increases almost linearly with the real contact area, which abides by the fundamental Bowden-Tabor law of nano-scale friction.
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Nesta dissertação investigamos como a ficção envolve o leitor. Para isso, partimos da rejeição a Homero declarada por Calímaco, observando que a suposta diferença entre a literatura preferida pelo público e a literatura preferida pela crítica depende de dois fatores distintos. O primeiro é o simples fato de a crítica ler profissionalmente e o público ler por prazer. O segundo está relacionado à distinção entre recepção e uso da literatura proposta por C.S. Lewis. Na recepção, a obra tende a ser admirada por si; no uso, tende a ser instrumentalizada como suporte para um devaneio em que os desejos do próprio leitor são vicariamente satisfeitos. Observamos que essa devaneio, que Lewis chama de construção egoísta de castelos, e que inclui uma variante mórbida, tem um paralelo na noção girardiana do duplo angélico. Contudo, o devaneio depende da simpatia como definida por Adam Smith, a qual por sua vez depende de certa aprovação moral. Investigamos portanto o tipo de personagem que conquista a aprovação moral do leitor, contrastando os heróis homéricos com os cavaleiros cristãos a fim de verificar como o cristianismo dirige a aprovação moral para as vítimas, fazendo com que os heróis da ficção sejam pessoas perseguidas ou marginalizadas.
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The adhesive properties of the gecko foot have inspired designs of advanced micropatterned surfaces with increased contact areas. We have fabricated micropatterned pillars of vertically aligned carbon nanotube forests with a range of pillar diameters, heights, and spacings (or pitch). We used nanoindentation to measure their elastic and orthogonal adhesion properties and derive their scaling behavior. The patterning of nanotube forests into pillar arrays allows a reduction of the effective modulus from 10 to 15 MPa to 0.1-1 MPa which is useful for developing maximum conformal adhesion. © 2012 American Chemical Society.
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Atomic force microscopy (AFM) and lateral force microscopy (LFM) were used simultaneously to analyze a model membrane bilayer structure consisting of a phospholipid outer monolayer deposited onto organosilane-derivatized mica surfaces, which were constructed by using painting and self-assembly methods. The phospholipid used as outer monolayer was dimyristoylphosphatidylcholine (DMPC). The hydrocarbon-covered substrate that formed the inner half bilayer was composed of a self-assembly monolayer (SAM) of octadecyltrichloroorganosilane (OTS) on mica. SAMs of DMPC were formed by exposing hydrophobic mica to a solution of DMPC in decane/isobutanol and subsequently immersing into pure water. AFM images of samples immersed in solution for varying exposure times showed that before forming a complete monolayer the molecules aggregated into dense islands (2.2-2.6 nm high) on the surface. The islands had a compact and rounded morphology. LFM, coupled with topographic data obtained with the atomic force mode, had made possible the distinction between DMPC and OTS. The rate constant of DMPC growth was calculated. This is the first systematic study of the SAM formation of DMPC by AFM and LFM imaging. It reveals more direct information about the film morphology than previous studies with conventional surface analytical techniques such as infrared spectroscopy, X-ray, or fluorescence microscopy.
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A kind of mimetic biomembrane-cast lipid film was made onto a glassy carbon electrode. Dopamine can be incorporated into the film. The oxidation of 2.0 x 10(-3) mol/L ascorbic acid with dopamine in the film was investigated. The oxidation overpotential of ascorbic acid was reduced by about 260 mV.
Resumo:
Kear, Adrian, 'Desire Amongst the Dodgems: Alain Platel and the Scene of Seduction', In: Contemporary Theatres in Europe: A Critical Companion, Joe Kelleher and Nicholas Ridout (eds), (New York: Routledge), pp.106-119, 2006 RAE2008
Resumo:
Cultural Marxist Theory, commonly known as theory, enjoyed a moment of extraordinary success in the 1970s, when the works of leading post-war French philosophers were published in English. After relocating to Anglophone academia, however, theory disavowed its original concerns and lost its ambition to understand the world as a whole, becoming the play of heterogeneities associated with postcolonialism, multiculturalism and identity politics, commonly referred to as postmodern theory. This turn, which took place during a period that seemed to have spelt the death of Marxism, the 1990s, induced many of its supporters to engage in an ongoing funeral wake designating the merits of theory and dreaming its resurgence. According to them, had theory been resurrected in historical circumstances completely different from those which had led to its rise, it would have never reacquired the significance that had originally connoted it. This thesis demonstrates how theory has survived its demise and entirely regained its prominence in our socio-political context marked by the effects of the latest crisis of capitalism and by the global threat of terrorisms rooted in messianic eschatologies. In its current form theory does no longer need to show allegiance to certain intellectual stances or political groupings in order to produce important reformulations of the projects it once gave life to. Though less overtly radical and epistemologically bounded, theory remains a necessary form of enquiry justified by the political commitment which originated it in the first place. Its voice continues to speak to us about justice ‘where it is not yet, not yet there, where it is no longer’ (Derrida, 1993, XVIII).
Resumo:
This paper explores the spatial conceptualisation of the themes of diaspora, displacement and desire in cinema, particularly in the work of Nuri Bilge Ceylan (Uzak) , Fatih Akin (Gegen Die Wand) and Michael Winterbottom (Code 46). All three directors explore the imagined cinematic city as a site of multiple (un)belongings and interrogate how notions of identity are displaced and disrupted by geopolitics, by the city and by cinema itself. Both Ceylan and Akin’s visions of Istanbul are haunted by Beyoglu, both as the site of Istanbul’s contemporary cultural regeneration and by unspoken histories repressed by the Republic’s offical rhetoric of Turkish identity. In contrast Akin and Winterbottom’s heterotopias of the hotel and the hospital provide possible metaphors for these dislocated global identities. This paper will engage with a series of questions. What is the (imagined) place created between the viewer and the screen, or is it a non-place? Do the identities/ memories created there produce a ‘third space’? This paper uses Winnicot, Soja and Bhabha to ask what that third space might be and its consequences for a contemporary global Turkish identity. If these films depict a (Freudian) screen memory of dislocated subjectivities then what is being suppressed and sutured?