970 resultados para Basic Research, Methedology


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We have studied a Bose-Einstein condensate of (87)Rb atoms under an oscillatory excitation. For a fixed frequency of excitation, we have explored how the values of amplitude and time of excitation must be combined in order to produce quantum turbulence in the condensate. Depending on the combination of these parameters different behaviors are observed in the sample. For the lowest values of time and amplitude of excitation, we observe a bending of the main axis of the cloud. Increasing the amplitude of excitation we observe an increasing number of vortices. The vortex state can evolve into the turbulent regime if the parameters of excitation are driven up to a certain set of combinations. If the value of the parameters of these combinations is exceeded, all vorticity disappears and the condensate enters into a different regime which we have identified as the granular phase. Our results are summarized in a diagram of amplitude versus time of excitation in which the different structures can be identified. We also present numerical simulations of the Gross-Pitaevskii equation which support our observations. (C) 2011 by Astro Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA

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Bendadaite, ideally Fe(2+)Fe(2)(3+)(AsO(4))(2)(OH)(2 center dot).4H(2)O, is a new member of the arthurite group It was found as a weathering product of arsenopyrite on a single hand specimen from the phosphate pegmatite Bendada. central Portugal (type locality) Co-type locality is the granite pegmatite of La via do Almerindo (Almerindo mine), Linopolis, Divmo das Laranjeiras county, Minas Gerais, Brazil Further localities are the Vein Negra mine, Copiapo province, Chile, mid-East, Bou Azzer district, Morocco, and Para Inferida yard, Fenugu Sibirt mine, Gonnosfanadiga, Medio Campidano Province, Sardinia. Italy Type bendadaite occurs as blackish green to dark brownish tufts (<0 1 mm long) and flattened radiating aggregates. in intimate association with an intermediate member of the scorodite-mansfieldite series It is monoclinic. space group P2(l/c). with a = 10 239(3) angstrom. b = 9 713(2) angstrom, c = 5 552(2) angstrom. beta = 94 11(2)degrees. = 550 7(2) angstrom(3). Z = 2 Electron-microprobe analysis yielded (wt %). CaO 0 04, MnO 0 03. CuO 006, ZnO 004. Fe(2)O(3) (total) 43 92, Al(2)O(3) 115. SnO(2) 0 10, As(2)O(5) 43 27. P(2)O(5) 1 86, SO(3) 0.03 The empirical formula is (Fe(0 52)(2+)Fe(0 32)(3+)rectangle(0 16))(Sigma 1 00)(Fe(1 89)(3+)Al(0 11))(Sigma 2 00)(As(1 87)P(0 13))(Sigma 2 00)O(8)(OH)(2 00) 4H(2)O based. CM 2(As,P) and assuming ideal 80, 2(OH), 4H2O and complete occupancy of the ferric on site by Fe(3+) and Al Optically, bendadaite is biaxial, positive, 2V(est) = 85+/-4 degrees, 2V(eale) = 88 degrees, with alpha 1 734(3). 13 1 759(3), 7 1 787(4) Pleochrosim is medium strong X pale reddish brown. Y yellowish brown, Z dark yellowish brown. absorption Z > V > X, optical dispersion weak, r > v. Optical axis plane Is parallel to (010), with X approximately parallel to a and Z nearly parallel to c Bendadaite has vitreous to sub-adamantine luster, is translucent and non-fluorescent It is brittle, shows irregular fracture and a good cleavage parallel to 1010} 3 15 0 10 g/cm(3), 3 193 g/cm3 (for the empirical formula) The five strongest powder diffraction lines [d in angstrom (I)(hkl] are 10 22 (10)(100), 7 036 (8)(110), 4 250 (5)(11 I), 2 865 (4)(311), 4 833 (3)(020,011) The d spacings are very similar to those of its Zn analogue, ojelaite The crystal structure of bendadaite was solved and refined using a crystal from the co-type locality with the composition (Fe(0 95)(2+)rectangle(0 05))(Sigma 1 00)(Fe(1 80)(3+)Al(0 20))Sigma(2 00)(As(1 48)P(0 52))(Sigma 2 00)O(8)) (OH)(2) 4H(2)O (R = 16%) and confirms an arthurite-type atomic arrangement

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Föreliggande vårdvetenskapliga studie har som syfte att avtäcka och synliggöra glädjesom idé i vårdandets värld. Glädje sammanbinds med vårdandet genom kärleken somden tongivande kraften hos glädje. Vårdandets sak har genom historien alltid varit attlindra lidande och att tjäna liv och hälsa i en anda av kärlek och barmhärtighet. Dennastudie om glädje i vårdandet har en övergripande idéhistorisk inriktning och resultatetsammanställs i form av ett idémönster. Tolkningen sker genom en hermeneutisk ansatsmed fokus på förståelse av själva vårdandet. För att djupare förstå glädje, dessursprungsidé, väsen och uttrycksformer granskas begreppet ’glädje’ och de näraliggandebegreppen ’glad’ och ’ljus’ i etymologiska ordböcker samt i svenska, engelska ochlatinska ordböcker. Som stöd för tolkningen används klassiska texter innehållandefilosofers tankar om glädje. Glädje som idé glimtar fram i form av ett sjufaldigtmönster. Detta mönster innehåller särdrag hos glädje och det hjärtas natur somrespektive särdrag förverkligas i. I andlig mening utgör hjärtat livets medelpunkt ochkänslornas hemvist. Mönstret bildar bakgrund och blir vägledande vid den hermeneutiska läsningen omglädje, så som den framträder i berättelser om vårdande under åren 1900–1933. Dehistoriska källorna utgörs av facktidskriften Svensk sjukskötersketidning, böcker medberättelser om vårdande, arkivmaterial samt läroböcker om vårdarbete. Resultatetmynnar ut i ett idémönster, där idéer om det som gör glädje verksamt som vårdandeframträder. Dessa är det sanna hjärtats rena glädje – kärlek, glädje är ett kärleksbevis.Det brinnande hjärtats djupa glädje – livsglädje, glädje inspirerar och genererar kraft.Det bärande hjärtats glansfulla glädje – generositet, glädje är en gåva till den andra medlöfte om hjälp. Det inbjudande hjärtats glittrande glädje – gemenskap, glädje inbjudertill gemenskap. Det upprymda hjärtats uppsluppna glädje – integration, glädje gör attmänniskan kan glömma sitt lidande och närma sig den hon önskar vara. Detstämningsfulla hjärtats högtidliga glädje – bevärdigande, glädje skapar en anda ochatmosfär där människan upplever sig hedrad. Det fridfulla hjärtats stora glädje –räddning, en glädje visar sig när människan har erhållit det som kan begäras av gott ochundsluppet ont och är förnöjd med sin levnads lott. Förhoppningen är att dennagrundforskning ska öppna för ett nytt seende som kan leda till att glädjeuppmärksammas i vårdandets värld och artikuleras där.

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In this thesis, the basic research of Chase and Simon (1973) is questioned, and we seek new results by analyzing the errors of experts and beginners chess players in experiments to reproduce chess positions. Chess players with different levels of expertise participated in the study. The results were analyzed by a Brazilian grandmaster, and quantitative analysis was performed with the use of statistical methods data mining. The results challenge significantly, the current theories of expertise, memory and decision making in this area, because the present theory predicts piece on square encoding, in which players can recognize the strategic situation reproducing it faithfully, but commit several errors that the theory can¿t explain. The current theory can¿t fully explain the encoding used by players to register a board. The errors of intermediary players preserved fragments of the strategic situation, although they have committed a series of errors in the reconstruction of the positions. The encoding of chunks therefore includes more information than that predicted by current theories. Currently, research on perception, trial and decision is heavily concentrated on the idea of pattern recognition". Based on the results of this research, we explore a change of perspective. The idea of "pattern recognition" presupposes that the processing of relevant information is on "patterns" (or data) that exist independently of any interpretation. We propose that the theory suggests the vision of decision-making via the recognition of experience.

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In this thesis, the basic research of Chase and Simon (1973) is questioned, and we seek new results by analyzing the errors of experts and beginners chess players in experiments to reproduce chess positions. Chess players with different levels of expertise participated in the study. The results were analyzed by a Brazilian grandmaster, and quantitative analysis was performed with the use of statistical methods data mining. The results challenge significantly, the current theories of expertise, memory and decision making in this area, because the present theory predicts piece on square encoding, in which players can recognize the strategic situation reproducing it faithfully, but commit several errors that the theory can¿t explain. The current theory can¿t fully explain the encoding used by players to register a board. The errors of intermediary players preserved fragments of the strategic situation, although they have committed a series of errors in the reconstruction of the positions. The encoding of chunks therefore includes more information than that predicted by current theories. Currently, research on perception, trial and decision is heavily concentrated on the idea of 'pattern recognition'. Based on the results of this research, we explore a change of perspective. The idea of 'pattern recognition' presupposes that the processing of relevant information is on 'patterns' (or data) that exist independently of any interpretation. We propose that the theory suggests the vision of decision-making via the recognition of experience.

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Sugarcane has an importance in Brazil due to sugar and biofuel production. Considering this aspect, there is basic research being done in order to understand its physiology to improve production. The aim of this research is the Base Excision Repair pathway, in special the enzyme MUTM DNA-glycosylase (formamidopyrimidine) which recognizes oxidized guanine in DNA. The sugarcane scMUTM genes were analyzed using four BACs (Bacterial Artificial Chromosome) from a sugarcane genomic library from R570 cultivar. The resulted showed the presence in the region that had homology to scMUTM the presence of transposable elements. Comparing the similarity, it was observed a highest similarity to Sorghum bicolor sequence, both nucleotide and peptide sequences. Furthermore, promoter regions from MUTM genes in some grass showed different cis-regulatory elements, among which, most were related to oxidative stress, suggesting a gene regulation by oxidative stress

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Radiobiocomplexes are used to obtain images in nuclear medicine and employed in basic research. Blood constituents labeled with technetium-99m (99mTc) have also been employed as radiobiocomplexes and used also experimental model for evaluation of the biological effects of natural or synthetic drugs. The analysis of the morphology and the morphometrics parameters (perimeter/área ratio) can be used to evaluate the effects of drugs upon the structure of the membrane of red blood cells. Cinnamomum zeylanicum (cinnamon) is a spice used as herbal medicine to treat diseases. The aim of this study was to evaluate the effect of in vitro and in vivo treatment with an aqueous cinnamon extract on the labeling of blood constituents with 99mTc and on the morphology of red blood cells from Wistar rats. In the in vitro treatment, isolated blood sample from animals were incubated with cinnamon extract. In the in vivo treatment, blood samples were also withdrawn from animals treated with cinnamon extract. In both cases, the radiolabeling of blood constituents was done. The morphological analysis of red blood cells was also done. As control, blood or animals treated with NaCl 0.9%. The data obtained on the labeling of blood constituents with 99mTc experiments indicated that the in vitro treatment with cinnamon extract was capable to decrease signiicantly (p<0.05) the percentage of radioactivity in cellular compartments and on the fixation of cellular and plasma proteins. These effects were not observed on the in vivo treatment. The results obtained for the morphology of red blood cells suggest that the in vitro and in vivo treatments did not alter the morphology and the perimeter/area ratio. The in vitro treatment with aqueous cinnamon extract could affect the membrane structures related with the oxidation status of the stannous ion pertechnetate ion, altering the labeling of blood constituentes with 99mTc. This study was a multidisciplinary experimental research. It was developed with the contribution of the different Departments and Services of the Hospital Universitário Pedro Ernesto of the Universidade do Estado do Rio de Janeiro

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Radionuclides have been used in Nuclear Medicine for diagnostic and treatment. In basic research, cellular and molecular structures are labeled with technetium-99m (99mTc) and used as radiobiocomplexes. Some natural or synthetic drugs are capable to alter the labeling of blood constituents with 99mTc, as well as in the biodistribution of radiobiocomplexes. Arctium lappa (Bardana) has been used to treat inflammatory processes. The aim of this work was to evaluate the effects of an extract of Bardana on the labeling of blood constituents with 99mTc, on the morphology of red blood cells, on the perimeter/area ratio of red blood cells and on the biodistribution of radiophamaceutical sodium pertechnetate in Wistar rats. Extract of Bardana was capable to alter the labeling of cellular compartment with 99mTc. Plasma and cellular proteins did not present alteration on the percentage of radioactivity (%ATI). Extract of Bardana was also capable to alter the morphology and the perimeter/area ratio of red blood cells. On the biodistribution of sodium pertechnetate in animals treated with the extract of Bardana, it was observed a small and significant uptake in liver, tooth and tongue, and a high and a significant uptake in stomach, lung and testis (p<0.05). In conclusion, these findings could be justified due to the effects of some chemical compounds in the Bardana extract. This study was a multidisciplinary experimental research. It was developed with the contribution of the different Departments and Services of the Hospital Universitário Pedro Ernesto of the Universidade Estadual do Rio de Janeiro

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The results of nanohardness measurements at a film surface and film-substrate interface are presented and discussed. An electron beam device was used to deposit a Ti film on a 304 stainless steel (304 SS) substrate. The diluted interface was obtained by thermal activated atomic diffusion. The. Ti film and Ti film-304 SS interface were analyzed by energy dispersive spectrometry and were observed using atomic force microscopy. The nanohardness of the Ti film-304 SS system was measured by a nanoindentation technique. The results showed the Ti film-304 SS interface had a higher hardness value than the Ti film and 304 SS substrate. The Ti film surface had a lower hardness due to the presence of a TiO2 thin layer.

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Background: ACE inhibitors have shown beneficial results in several studies after myocardial infarction (MI). However, these studies have shown conflicting results about the ideal starting time of the ACE inhibitors administration after MI and the importance of infarct size.Objectives: This study was designed to assess the long-term effects of lisinopril on mortality, cardiac function, and ventricular fibrosis after MI, in rats.Methods: Lisinopril (20 mg/kg/day) was given on day 1 or 21 days after coronary occlusion in small or large infarctions.Results: the mortality rate was reduced by 39% in early treatment and 30% in delayed treatment in comparison to the untreated rats. Early treatment reduced cardiac dysfunction in small MIs; however, delayed treatment did not. No statistical difference was observed among the groups for large MIs. No statistical difference was observed among the groups with large or small MIs on myocardial hydroxyproline concentration.Conclusions: Both early and delayed treatments with lisinopril increased survival. Treatment exerts no marked effects on fibrosis; early treatment has exerted beneficial influences on cardiac function whereas delayed treatment had no consistent effects. The protective effect of lisinopril is detectable only in small (< 40% of LV) MIs.

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Characterization of the peptide content of venoms has a number of potential benefits for basic research, clinical diagnosis, development of new therapeutic agents, and production of antiserum. In order to analyze in detail the peptides and small proteins of crude samples, techniques such as chromatography and mass spectrometry have been employed. The present study describes the isolation, biochemical characterization, and sequence determination of a novel peptide, named Orpotrin from the venom of Potamotrygon gr. orbignyi. The natural peptide was shown to be effective in microcirculatory environment causing a strong vasoconstriction. The peptide was fully sequenced by de novo amino acid sequencing with mass spectrometry and identified as the novel peptide. Its amino acid sequence, HGGYKPTDK, aligns only with creatine kinase residues 97-105, but has no similarity to any bioactive peptide. Therefore, possible production of this peptide from creatine kinase by limited proteolysis is discussed. Taken together, the results indicate the usefulness of this single-step approach for low molecular mass compounds in complex samples such as venoms. (c) 2006 Elsevier B.V. All rights reserved.

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The magnetic circular dichroism (MCD) of F2+ centers in KCl:SH- has been measured in absorption in the 1ssigma(g) --> 2p(y)pi(u) transitions at 493 and 509 nm, with fields up to 5 T and in the temperature range 1.5 K < T < 77 K. Within the limit of detection, no MCD is observed in the near infrared transition 1ssigma(g) --> 2psigma(u) as well as in both emissions 2ppi(u) --> 1ssigma(g) and 2psigma(u) --> 1ssigma(g). The optical detection of EPR in the F2+ ground state presents an isotropic single band with g = 1.965 +/- 0.007. The spin-lattice relaxation measured at H = 0.32 T is typical of a direct process T-1 = 4.3 x 10(-2_ coth (gmu(B)H/2k(B)T). The spectral variation of the MCD is calculated using perturbation theory to first order. The Hamiltonian includes the spin-orbit interaction in the 2ppi(u) excited state and the orbital molecular wave functions are obtained by a linear combination of 1s and 2p atomic orbitals. The calculated MCD is in good agreement with the observed one, for the spin-orbit interaction strength Pound(z) = 3.6 meV.