970 resultados para C. G. Boerner (Firm).


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Serotonin (5-HT) is involved in the fine adjustments at several brain centers including the core of the mammal circadian timing system (CTS) and the hypothalamic suprachiasmatic nucleus (SCN). The SCN receives massive serotonergic projections from the midbrain raphe nuclei, whose inputs are described in rats as ramifying at its ventral portion overlapping the retinohypothalamic and geniculohypothalamic fibers. In the SCN, the 5-HT actions are reported as being primarily mediated by the 5-HT1 type receptor with noted emphasis for 5-HT(1B) subtype, supposedly modulating the retinal input in a presynaptic way. In this study in a New World primate species, the common marmoset (Callithrix jacchus), we showed the 5-HT(1B) receptor distribution at the dorsal SCN concurrent with a distinctive location of 5-HT-immunoreactive fibers. This finding addresses to a new discussion on the regulation and synchronization of the circadian rhythms in recent primates. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

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We have investigated if a new LEDs system has enough efficient energy to promote efficient shear and tensile bonding strength resistance under standardized tests. LEDs 470 +/- 10 nm can be used to photocure composite during bracket fixation. Advantages considering resistance to tensile and shear bonding strength when these systems were used are necessary to justify their clinical use. Forty eight human extracted premolars teeth and two light sources were selected, one halogen lamp and a LEDs system. Brackets for premolar were bonded through composite resin. Samples were submitted to standardized tests. A comparison between used sources under shear bonding strength test, obtained similar results; however, tensile bonding test showed distinct results: a statistical difference at a level of 1% between exposure times (40 and 60 seconds) and even to an interaction between light source and exposure time. The best result was obtained with halogen lamp use by 60 seconds, even during re-bonding; however LEDs system can be used for bonding and re-bonding brackets if power density could be increased.

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The Pierre Auger Collaboration has reported. evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > E(th) = 5.5 x 10(19) eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > E(th) are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above E(th)/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above E(th) are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

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The optical, magnetic and structural properties of Eu doped low silica calcium aluminosilicate glasses were investigated. The optical absorption coefficient presented two bands at 39 246 and 29 416 cm(-1), which were assigned respectively to the 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (T(2g)), and 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (E(g)) transitions of Eu(2+). The fluorescence measured at 300 K on a sample doped with 0.5 wt% of Eu(2)O(3) exhibited a broad band centered at 17 350 cm(-1), which is attributed to the 4f(6)5d -> 4f(7) transition of Eu(2+), whereas the additional peaks are due to the (5)D(0) -> (7)F(J) (J = 1, 2, 4) transitions of Eu(3+). From magnetization and XANES data it was possible to evaluate the fractions of Eu(2+) and Eu(3+) for the sample doped with 0.5 and 5.0 wt% of Eu(2)O(3), the values of which were approximately 30 and 70%, respectively.

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The aim of task scheduling is to minimize the makespan of applications, exploiting the best possible way to use shared resources. Applications have requirements which call for customized environments for their execution. One way to provide such environments is to use virtualization on demand. This paper presents two schedulers based on integer linear programming which schedule virtual machines (VMs) in grid resources and tasks on these VMs. The schedulers differ from previous work by the joint scheduling of tasks and VMs and by considering the impact of the available bandwidth on the quality of the schedule. Experiments show the efficacy of the schedulers in scenarios with different network configurations.

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There has been great interest in deciding whether a combinatorial structure satisfies some property, or in estimating the value of some numerical function associated with this combinatorial structure, by considering only a randomly chosen substructure of sufficiently large, but constant size. These problems are called property testing and parameter testing, where a property or parameter is said to be testable if it can be estimated accurately in this way. The algorithmic appeal is evident, as, conditional on sampling, this leads to reliable constant-time randomized estimators. Our paper addresses property testing and parameter testing for permutations in a subpermutation perspective; more precisely, we investigate permutation properties and parameters that can be well approximated based on a randomly chosen subpermutation of much smaller size. In this context, we use a theory of convergence of permutation sequences developed by the present authors [C. Hoppen, Y. Kohayakawa, C.G. Moreira, R.M. Sampaio, Limits of permutation sequences through permutation regularity, Manuscript, 2010, 34pp.] to characterize testable permutation parameters along the lines of the work of Borgs et al. [C. Borgs, J. Chayes, L Lovasz, V.T. Sos, B. Szegedy, K. Vesztergombi, Graph limits and parameter testing, in: STOC`06: Proceedings of the 38th Annual ACM Symposium on Theory of Computing, ACM, New York, 2006, pp. 261-270.] in the case of graphs. Moreover, we obtain a permutation result in the direction of a famous result of Alon and Shapira [N. Alon, A. Shapira, A characterization of the (natural) graph properties testable with one-sided error, SIAM J. Comput. 37 (6) (2008) 1703-1727.] stating that every hereditary graph property is testable. (C) 2011 Elsevier B.V. All rights reserved.

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Purpose: To evaluate the microvessel density by comparing the performance of anti-factor VIII-related antigen, anti-CD31 and, anti-CD34 monoclonal antibodies in breast cancer. Methods: Twenty-three postmenopausal women diagnosed with Stage II breast cancer submitted to definitive surgical treatment were evaluated. The monoclonal antibodies used were anti-factor VIII, anti-CD31 and anti-CD34. Microvessels were counted in the areas of highest microvessel density in ten random fields (200 x). The data were analyzed using the Kruskal-Wallis nonparametric test (p < 0.05). Results: Mean microvessel densities with anti-factor VIII, anti-CD31 and anti-CD34 were 4.16 +/- 0.38, 4.09 +/- 0.23 and 6.59 +/- 0.42, respectively. Microvessel density as assessed by anti-CD34 was significantly greater than that detected by anti-CD31 or anti-factor VIII (p < 0.0001). There was no statistically significant difference between anti-CD31 and anti-factor VIII (p = 0.4889). Conclusion: The density of stained microvessels was greater and staining was more intense with anti-CD34 compared to anti-CD31 and anti-factor VII-related antigen.

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Can Boutet de Monvel`s algebra on a compact manifold with boundary be obtained as the algebra Psi(0)(G) of pseudodifferential operators on some Lie groupoid G? If it could, the kernel G of the principal symbol homomorphism would be isomorphic to the groupoid C*-algebra C*(G). While the answer to the above question remains open, we exhibit in this paper a groupoid G such that C*(G) possesses an ideal I isomorphic to G. In fact, we prove first that G similar or equal to Psi circle times K with the C*-algebra Psi generated by the zero order pseudodifferential operators on the boundary and the algebra K of compact operators. As both Psi circle times K and I are extensions of C(S*Y) circle times K by K (S*Y is the co-sphere bundle over the boundary) we infer from a theorem by Voiculescu that both are isomorphic.

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The analysis of the IR carbonyl band of the N,N-diethyl-2-[(4`-substituted)phenylsulfonyl]acetamides Et(2)NC(O)CH(2)S(O)(2)-C(6)H(4)-Y (Y = OMe 1, Me 2,1-13, Cl 4, Br 5, NO(2) 6) supported by B3LYP/6-31G(d,p) calculations for 3, indicated the existence of three pairs (anti and syn) of cis (c) and gauche (g(1) and g(2)) conformers in the gas phase, being the gauche conformers significantly more stable than the cis ones. The anti geometry is more stable than the syn one, for each pair of cis and gauche conformers. The summing up of the orbital (NBO analysis) and electrostatic interactions justifies quite well the populations and the v(CO) frequencies of the anti and syn pairs of c, g(1) and g(2) conformers. The IR higher carbonyl frequency component whose population is ca. 10%, in CCl(4), may be ascribed to the least stable and most polar cis conformer pair (in the gas phase) and the lower frequency component whose population is ca. 90%, to the summing up of the populations of the two most stable and least polar gauche conformer pairs (g(1) and g(2)) (in the gas phase). The reversal of the cis(c)/gauche (g(1) + g(2)) population ratio observed in chloroform ca. 60% (cis)/40% (gauche) and the occurrence of the most polar cis(c) conformer only, in acetonitrile, strongly suggests the coalescence of the two gauche components in a unique carbonyl band in solution. A further support to this rationalization is given by the single point PCM solvation model performed by HF/6-31G(d,p) method, which showed a progressive increase of the c/(g(1) + g(2)) ratio going from gas to CCl(4), to CHCl(3) and to CH(3)CN. X-ray single crystal analysis of 4 indicates that this compound assumes, in the solid state, the syn-clinal (gauche) conformation with respect to the [O=C-CH(2)-S] moiety, and the most stable anti geometry relative to the [C(O)N(CH(2)CH(3))(2)] fragment. In order to obtain larger energy gain from the crystal packing the molecules of 4 are linked in centrosymmetric dimers through two C-H center dot center dot center dot O interactions (C-H([O-Ph])center dot center dot center dot O([SO2])) forming a step ladder. (C) 2011 Elsevier B.V. All rights reserved.

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The analysis of the IR carbonyl band of the 2-substituted N-methoxy-N-methylacetamides Y-CH(2)C(O)-N(OMe)Me (Y = F1, OMe 2, OPh 3, Cl 4), supported by B3LYP/6-311++G(3df, 3pd) calculations along with the NBO analysis for 1-4, indicated the existence of cis-gauche conformers i.e. (c) and (g) for 1 and 3, (c(1), c(2)) and (g(1), g(2)) for 2, and (c) and (g(1), g(2)) for 4. In the gas phase, the g conformer population prevails over the c one, for 1 and 3, the (c(1) + c(2)) population prevails over the (g(1) + g(2)) one for 2, and the (g(1) + g(2)) conformer population is more abundant than (c) one for 4. In n-hexane solution, the cis conformer is more abundant for 1-3. The occurrence of Fermi resonance in the nu(CO) region, in n-hexane, precludes the estimative of relative populations of the (c, g(1), g(2)) conformers for 4. The SCI-PCM calculations agree with the solvent effect on the nu(CO) band component relative intensities for 1-3. NBO analysis showed that the n(N) -> pi.(CO), orbital interaction is the main factor which stabilizes the gauche (g, g(1), g(2)) conformers for 1-4 into a larger extent relative to the cis (c, c(1), c(2)) ones. The n(y) -> pi(.)(Co,) sigma(C-Y) -> pi.(CO,) pi(CO) -> sigma(C-Y) and 7co orbital interactions still contribute, but into a minor extent for the stabilization of the gauche conformers relative to the cis ones. The existence of some pyramidalization at the nitrogen atom of the Weinreb amides 1-4 is responsible for the occurrence of Y(delta)-(4)center dot center dot center dot O(delta)-(9) and Y(delta)-(4)center dot center dot center dot N(delta)-(7) short contacts in the gauche (g, g(1), g(2)) conformers, which originates strong repulsive Coulombic interactions, acting in opposition to the large orbital stabilization of the gauche conformer with respect to the cis one. Therefore, a delicate balance of the Coulombic and orbital interactions seems to be responsible for the observed stabilization of the gauche (g, g(1), g(2)) and cis (c, c(1), c(2)) conformers, both in the gas phase and in the solution for 1-4. However, the cis conformer predominance, in non polar solvents, for the 2-substituted N-methoxy-N-methyl acetamides 1-3, bearing in a first raw (fluorine and oxygen) atoms, is in the opposite direction to the gauche conformer preference for the corresponding 2-substituted N,N-dialkyl-acetamides. (C) 2010 Elsevier B.V. All rights reserved.

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Dye-sensitized solar cells, named by us Dye-Cells, are one of the most promising devices for solar energy conversion due to their reduced production cost and low environmental impact, especially those sensitized by natural dyes. The efficiency and stability of devices based on natural sensitizers such as mulberry (Morus alba Lam), blueberry (Vaccinium myrtillus Lam), and jaboticaba`s skin (Mirtus cauliflora Mart) were investigated. Dye-Cells prepared with aqueous mulberry extract presented the highest P(max) value (1.6 mW cm(-2)) with J(sc) = 6.14 mA cm(-2) and V(oc) = 0.49 V, Photoelectrochemical parameters of 16 cm(2) active area devices sensitized by mulberry dye were constant for 14 weeks of continuous evaluation. Moreover, the cell remained stable even after 36 weeks with a fairly good efficiency. Therefore, mulberry dye opens up a perspective of commercial feasibility for inexpensive and environmentally friendly Dye-Cells. (C) 2009 Elsevier B.V. All rights reserved.

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The (bio)degradation of polyolefins can be accelerated by modifying the level of crystallinity or by incorporation of carbonyl groups by adding pro-oxidants to masterbatches or through exposure to ultraviolet irradiation. In this work we sought to improve the degradation of PP by adding cobalt, calcium or magnesium stearate to Ecoflex(R), PP or Ecoflex(R)/PP blends. The effect of the pro-oxidants on biodegradability was assessed by examining the mechanical properties and fluidity of the polymers. PP had higher values for tensile strength at break and Young`s modulus than Ecoflex(R), and the latter had little influence on the properties of PP in Ecoflex(R)/PP blends. However, the presence of pro-oxidants (except for calcium) reduced these properties. All of the pro-oxidants enhanced the fluidity of PP, a phenomenon that facilitated polymer degradation at high temperatures. (C) 2009 Elsevier Ltd. All rights reserved.

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In recent times, increasing attention has been paid to the use of renewable resources particularly of plant origin keeping in view the ecological concerns, renewability and many governments passing laws for the use of such materials. On the other hand, despite abundant availability of lignocellulosic materials in Brazil, very few attempts have been made about their utilization, probably due to lack of sufficient structure/property data. Systematic studies to know their properties and morphology may bridge this gap while leading to value addition to these natural materials. Chemical composition, X-ray powder diffraction, and morphological studies and thermal behavior aspects in respect of banana, sugarcane bagasse sponge gourd fibers of Brazilian origin are presented. Chemical compositions of the three fibers are found to be different than those reported earlier. X-ray diffraction patterns of these three fibers exhibit mainly cellulose type I structure with the crystallinity indices of 39%, 48% and 50% respectively for these fibers. Morphological studies of the fibers revealed different sizes and arrangement of cells. Thermal stability of all the fibers is found to be around 200 degrees C. Decomposition of both cellulose and hemicelluloses in the fibers takes place at 300 degrees C and above, while the degradation of fibers takes place above 400 degrees C. These data may help finding new uses for these fibers. (C) 2009 Elsevier B.V. All rights reserved.

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Denna uppsats handlar om förekomsten av Antisemitism i den svenska s.k. Vit makt-musiken. Uppsatsens syfte är att kartlägga förekomsten av antisemitism i tre vit makt- band: Pluton Svea, Storm och Dirlewanger. Analysen sker genom att texterna till tvÃ¥ album av varje band studeras. Metoden är bÃ¥de kvalitativ som kvantitativ och bland annat sÃ¥ undersöks olika typer av antisemitiska uttalanden som därefter nivÃ¥sätts enligt en, av författaren, modifierad skala konstruerad av forskaren John C.G. Röhl. Resultatet av denna undersökning visar att antisemitism är ständigt närvarande i denna musikstil. Dock tar den sig olika uttryck beroende pÃ¥ vilket band det ¤ller. I de album som är producerade under 2000-talet tycks även en viss nedtoning av den vÃ¥ldsammaste formen av antisemitism kunna ses.

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The Indian author Rabindranath Tagore was received like royalty during his visits to the West after winning the Nobel Prize in 1913. Dreams of foreign cultures offered a retreat from a complicated age. In a time when the West appeared to be living under threat of disintegration and when industrialism seemed like a cul-de-sac, he appeared to offer the promise of a return to a lost paradise, a spiritual abode that is superior to the restless Western culture. However, Tagore’s popularity faded rapidly, most notably in England, the main target of his criticism. Soon after Tagore had won the Nobel Prize, the English became indignant at Tagore’s anti-colonial attitude.Tagore visited Sweden in 1921 and 1926 and was given a warm reception. His visits to Sweden can be seen as an episode in a longer chain of events. It brought to life old conceptions of India as the abode of spirituality on earth. Nevertheless, interest in him was a relatively short-lived phenomenon in Sweden. Only a few of his admirers in Sweden appreciated the complexity of Tagore’s achievements. His “anathema of mammonism”, as a Swedish newspaper called it, was not properly received. After a steady stream of translations his popularity flagged towards the end of the 1920s and then almost disappeared entirely. Tagores visits in Sweden gave an indication that India was on the way to liberate itself from its colonial legacy, which consequently contributed to the waning of his popularity in the West. In the long run, his criticism of the drawbacks in the western world became too obvious to maintain permanent interest. The Russian author Fyodor Dostoyevskiy’s Crime and Punishment (1866) has enticed numerous interpretations such as the purely biographical approach. In the nervous main character of the novel, the young student Raskolnikov, one easily recognizes Dostoyevskiy himself. The novel can also be seen as a masterpiece of realistic fiction. It gives a broad picture of Saint Petersburg, a metropolis in decay. Crime and Punishment can also be seen as one of the first examples of a modern psychological novel, since it is focused on the inner drama of its main character, the young student Raskolnikov. His actions seem to be governed by mere coincidences, dreams and the spur of the moment. it seems fruitful to study the novel from a psychoanalytical approach. In his book Raskolnikov: the way of the divided towards unity in Crime and Punishment (1982), a Swedish scholar, Owe Wikström, has followed this line of interpretation all the way to Freud’s disciple C G Jung. In addition to this, the novel functions as an exciting crime story. To a large extent it is Viktor Sjklovskij and other Russian formalists from the 1920s and onwards who have taught the western audience to understand the specific nature of the crime story. The novel could be seen as a story about religious conversion. Like Lasarus in the Bible (whose story attracts a lot of attention in the novel) Raskolnikov is awakened from the dead, and together with Sonja he starts a completely new life. The theme of conversion has a special meaning for Dostoyevskiy. For him the conversion meant an acknowledgement of the specific nature of Russia itself. Crime and punishment mirrors the conflict between traditional Russian values and western influences that has been obvious in Russia throughout the history of the country. The novel reflects a dialogue that still continues in Russian society. The Russian literary historian Mikhail Bakhtin, who is probably the most famous interpreter of the works of Dostoyevskiy, has become famous precisely by emphasizing the importance of dialogues in novels like Crime and Punishment. According to Bakhtin, this novel is characterized by its multitude of voices. Various ideas are confronted with each other, and each one of them is personified by one of the characters in the novel. The author has resigned from his position as the superior monitor of the text, and he leaves it to the reader to decide what interpretation is the correct one..The aim of the present study is thus to analyze the complex reactions in the west to Tagore’s visits in Sweden and to Fyodor Dostoyevskiys novel Crime and Punishment.. This leads to more general conclusions on communication between cultures.