Showing papers by "Universidade Federal de Santa Catarina published in 1984"

Molecular motion and conformational defects in odd-numbered paraffins

Abstract: A small-angle x-ray diffraction study using synchrotron radiation of paraffins ${\mathrm{C}}_{n}{\mathrm{H}}_{2n+2}$ with $19\ensuremath{\le}n\ensuremath{\le}27$ as a function of the temperature allowed us to characterize the molecular disorders of the rotator phases, associated with longitudinal molecular motions and conformational defects of the molecular chains. The magnitude of these disorders increases with the molecular length, in agreement with previous infrared-spectroscopy results. Indications of correlations between the concentration of conformational defects, amplitude of the longitudinal motion, and orientational molecular disorder were established.

Asymptotic Reproducibility in Nonlinear Systems and Attitude Control of Gyrostat

Abstract: A control law is presented for asymptotic function reproducibility in a class of nonlinear-systems such that the output of the system asympotically tends to a given function. The controller consists of a prefilter and a servocompensator. Based on this result, a nonlinear feedback control law for the attitude control of a satellite containing symmetric rotors, in a circular orbit, is derived. In the closed-loop system, given trajectories of pitch, yaw, and roll angles are asymptotically followed, and set point control of attitude is accomplished. Digital simulation results are presented to show the capability of the nonlinear controller.

Structure and molecular disorder in three modifications of a binary C23H48-C24H50 paraffin

Abstract: The temperature dependence of the intensities of the (00l) X-ray reflections from a binary paraffin (C23H48-25 % C 24H50) was determined, in order to obtain structural parameters related to the molecular disorder and intramolecular defects. The long lattice spacing was also determined as a function of temperature. All these results are compared with the temperature dependence of the ratio of the two short lattice parameters. The clear correlation of all of these experimental results provides a close characterization of the molecular structures and their changes at the various solid state phase transitions.

Effects of ketamine on experimental animal models of aggression.

Abstract: The dose-response effects of ketamine, an intravenous anesthetic with psychotomimetic properties which is a ketone derivative of phencyclidine, were evaluated in several experimental animal models of aggression. Low doses of ketamine (3 and 5 mg/kg) administered intraperitoneally showed a tendency to increase aggressiveness in REM sleep-deprived, food-deprived + apomorphine (20 mg/kg) pretreated rats, and in socially isolated mice. Ketamine (10 mg/kg) blocked aggressive behavior in food-deprived, apomorphine-pretreated rats probably because of locomotor activity impairment. Ketamine (3, 5 or 10 mg/kg) did not induce mouse-killing behavior in non-muricide rats. However, ketamine inhibited predatory aggression of muricide rats at a dose which did not affect ambulation (3 mg/kg). These data show that ketamine, like phencyclidine, has different effects on aggressive behavior which depend on the experimental model used.

Contribuição ao conhecimento das Diatomáceas do Rio Tubarão - Santa Catarina - Brasil

Abstract: O presente trabalho e o resultado do estudo taxonomico e qualitativo de diatomaceas (Chrysophyta - Bacillariophyceae) do rio Tubarao, no espaco compreendido entre as pontes Nereu Ramos e Jose Santos. Tubarao, Estado de Santa Catarina. Este estudo baseou-se na analise de 88 amostras coletadas em 8 estacoes, no periodo compreendido entre setembro de 1982 a setembro de 1983. Foram identificados um total de 178 taxons especificos e infraespecificos, que se encontram distribuidos em 10 familias e 27 generos. Dos taxons identificados. 78 sao citacoes novas para o Estado de Santa Catarina. Sao incluidos dados ecologicos. citacoes anteriores para o Estado. medidas e comentarios.

The Synthesis, Thermodynamic and Optical Properties of the Homologus Series 4′alkyloxy Benzoinilidene 4-n-Propyloxy Aniline

Abstract: The series of 4,4’ alkyloxy Benzoinilidene 4-n-propyloxy aniline was synthesized varying the number carbon atoms in the alkyloxy chain. The temperatures and enthalpies of the phase transitions were determined, as were the indices of refraction. Normal nematic phases are found for n = .5 to n = 10, and monotropic nematic phases for c = 4, 11, 12 and 16. For n = 10 to 16 smectic phases were observed which are monotropic and unstable.

Contribuição ao levantamento taxonômico das algas marinhas bentônicas do mangue do Itacorubi - Florianópolis - Ilha de Santa Catarina - Brasil. I - Chlorophyta

Abstract: The present work is about the marine benthic algae RHODOPHYTA division, collected from the Itacorubi mangrove, in FlorianOpolis, Island of Santa Catarina, Santa Catarina State, Brazil.(27° 34'05" Lat. S e 48°30'45" Long. W.) There were identified 9 taxa, distribuited in 5 genera. Two species are reported for the firsttime for the Santa Catarina State: Caloglossa ogasawaraensis Okamura and Murrayella periclados (C. Agardh) Schmitz. We present a list of the species with descriptions contaning ecological observations, reprodutive stages, monthly distribution, association among the species and substract preference.

Mechanism of action of isoprenaline, isoxuprine, terbutaline and orciprenaline on gravid human isolated myometrium. Influence of the neuronal uptake process.

Abstract: The present report analyzes the relative potencies and the mechanism of action of isoprenaline (Iso), isoxsuprine (Isox), terbutaline (Terb) and orciprenaline (Orc) on gravid isolated human myometrium in either spontaneous or in K+-induced contractions. Spontaneous activity was observed in 80% of the strips studied and the rate of contractions was 3.22 +/- 0.21 per 15 min. Dose-dependent inhibition of spontaneous contractions was observed with all the agonists. Preincubation with cocaine, 10(-5) M, shifted the inhibitory dose-response curves of Iso and Orc to the left, 16.6- and 23.3-fold respectively. The rank order of relative potencies was: Iso much greater than Isox greater than Terb greater than Orc in the absence and Iso much greater than Isox greater than Orc greater than Terb in the presence of cocaine. In the strips stimulated with K+, 80 mM, Isox, Terb and Orc produced only 20-30% inhibition while Iso was without effect. The incubation with propranolol (10(-8) -10(-4) M) did not modify the inhibitory response produced by Isox, Terb and Orc, but produced a parallel shift to the right of the Iso dose-response curve. Dose-ratio experiments yielded a straight line, and a Schild plot showed a pA2 value of 8.5 +/- 0.26 (slope = 2.76 +/- 0.47). The results with Iso confirm the existence of beta-adrenoreceptors in gravid human myometrium. On the other hand, in view of the low potency of Isox, Terb and Orc, and also the inability of propranolol to block their responses, it is suggested that the relaxant effects of these drugs are not mediated by beta-adrenoreceptors.

Estrutura jurídica do crime

Abstract: Que os juristas alemaes percam tempo com tanta futilidade nao deixa de ser compreensivel, vitimas que sao do ambiente cultural respirado nos ultimos seculos. Dificilmente o penalista germânico se libertara da conviccao de que se encontra historicamente destinado a desvendar o falso enigma da anatomia juridica do crime e da pena. Dir-se-ia que persistem, nele, as ilusoes de uma vocacao filosofica dirigida a perquiricao cada vez mais profunda dos atomos e essencias do "juridico", temporariamente escondidos a percepcao humana. E ele entao vai a luta, dissecando a seu modo a mosca azul de Machado de Assis, sem que a veja fragmentada e morta, ja que trabalha com a forca da fe e o vigor da clarividencia introspectiva. E escreve livros, artigos, conferencias, distinguindo e subdistinguindo; consertando aqui, retocando ali, dinamitando mais abaixo, sob protestos ou aplausos de colegas que retornam ao tema com novas distincoes, acrescimos e adendos. E nao ha mal nenhum, naquelas plagas, haja vista uma organizacao social e politica que permite e estimula esses jogos e charadas de adultos altamente intelectualizados, de quem nao se espera que, de repente, comecem a plantar batata.

Simple basis for hydrogenic atoms in magnetic fields

Abstract: A field-dependent hydrogenic basis is used to obtain the evolution of the energy spectrum of atoms in strong (\ensuremath{\sim}${10}^{8}$ G) and uniform magnetic fields. The basis allows results to be derived analytically. Numerical values for the first 13 excited states of hydrogen are found to be in very good agreement with much more elaborate calculations of Smith et al. and of Brandi. In addition, the possibility of having a remnant type of degeneracy in the presence of the magnetic field is investigated.

Caracterização das qualidades de narrativas em pré-escolares

Abstract: Procuraremos caracterizar, neste artigo, as diferencas entre uma boa e ma narrativa infantil, aplicando uma versao expandida do modelo de Stein & Glenn (1979), num corpus retirado de uma amostragem de populacao de pre-escolares, conforme tabela 1. As funcoes mais importantes da narrativa que fundamentam o debate sao as de constituirem um dos instrumentos utilizados em todas as culturas para a ordenacao da experiencia l , para o desenvolvimento da competencia comunicativa 2 , para a manifestacao estetica2 e para a elaboracao dos conflitos infantis4. Nao se restringem, pois, as funcoes assinaladas por Embree (1978): referencial e cognitiva; social e avaliativa; ou as de Labov & Waletzky (1967): referencial e avaliativa.

Estudo bibliometrico : analise de citacoes no periodico " Scientometrics "

Abstract: Analise de citacoes, de 1978 a 1982, no periodico Scientometrics oublicado em Amsterdam e especializado em cientometria. Nos 22 fasciculos dos 4 primeiros volumes da colecao registra-se a ocorrencia de 294 periodicos com 1164 citacoes. A origem identificada no Ulrlch's aponta 102 periodicos norte-americanos, 35 periodicos ingleses e 23 periodicos sovieticos. O periodico mais produtivo e o Social Studies of Science, com 137 citacoes. A base de dados foi analisada conforme a lei de Bradford, mas inferencias podem ser feitas, com o emprego da lei de Lotka e do elitismo de Price e tambem com o emprego de outros principios, leis e instrumentos da bibliometria. Descritores Bibliometria. Analise Quantitativa. Periodicos. Analise de Citacoes. Abstract Citation analysis of the periodical Scientometrics,years 1978-1982; registering 294 titles with 1164 citations in the 22 issues covered, the origin of these titles being: 102 American, 35 English, 23 Russian.The most productive is Social Studies of Science with 137 citations. The data base was analyzed according to Bradford's law but inferences can alsobe made with application of Lotka's law, Price's elitism as well as other principies, laws and instruments of bibliometry

New structure for an adaptive servomechanism controller

Abstract: A new stable adaptive controller structure for ensuring asymptotic tracking with disturbance rejection is proposed. The controller structure is identical to the robust servomechanism controller structure when the adaptation is over. The process is assumed to be a linear minimal-phase process. The exogenous signals may be unbounded, but satisfy a known linear difference equation. The parameter adaptation algorithm ensures global convergence of the tracking error.