Showing papers by "Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto published in 1998"
TL;DR: The hermit crab Calcinus tibicen is sexually dimorphic in relation to size, with a higher growth rate in males and the sex-ratio pattern changes with season, indicating that it is more a function of season or habitat than of size.
Abstract: The population of the hermit crab Calcinus tibicen in the Ubatuba region was studied with emphasis on seasonal abundance, seasonal size-frequency distribution, sex-ratio, and reproductive period based on the percentage of ovigerous females. The animals were collected at 2-month intervals for 2 consecutive years (from January 1993 to November 1994). Total mean animal size in shield length was 5.14 ± 1.23 mm for males, 4.23 ± 0.79 mm for females, and 4.53 ± 0.60 for ovigerous females. A discontinuity in reproduction was observed, with an absence of ovigerous females in July (winter) and a high incidence from September to May (spring to autumn). Calcinus tibicen is sexually dimorphic in relation to size, with a higher growth rate in males. The sex-ratio pattern changes with season, indicating that it is more a function of season or habitat than of size.
76 citations
TL;DR: In this paper, a scanning electron microscopy (SEM) observation of the dry latex and fracture surfaces reveals the coexistence of different crystallographic arrangements, in which particle positions are correlated for tens of crystallographic planes.
61 citations
TL;DR: In this article, the catalytic activity of the Ru(4,4′-Me2bpy)2(PPh3)(H2O)](ClO4)2 has been investigated at pH 6.5 in the homogeneous electrooxidation of benzylic compounds.
47 citations
TL;DR: The high-performance liquid chromatographic method was precise and accurate for the three compounds, as judged by the coefficients of variation and relative errors observed.
46 citations
TL;DR: Besides pigmentation, other developmental events were also altered in treated bees: pupal development was shortened, and the expression of esterase-6 activity was shifted with the precocious initiation of this process in treated pupae.
35 citations
TL;DR: In this paper, polypyridyl complexes of ruthenium in aqueous media were studied and a relationship between redox potential (E 1/2 ) of the complexes and reactivity was established.
Abstract: 1-pentanol, 1-4-butanediol, 1,2-butanediol, 4-methoxybenzyl alcohol and phthalic alcohol were oxidized electrocatalytically by polypyridyl complexes of ruthenium in aqueous media. [Ru II (tpy)(bpy)(OH 2 )] 2+ , [Ru II (bpy) 2 py(OH 2 )] 2+ (py=pyridine), [Ru II (tpy)(phen)(OH 2 )] 2+ (phen=1,10-phenanthroline), cis -[Ru II (bpy) 2 (OH 2 ) 2 ] 2+ , trans -[Ru II (bpy) 2 (OH 2 ) 2 ] 2+ and trans -[Ru VI (trpy)(O) 2 (OH 2 )] 2+ were the studied complexes. A relationship between redox potential ( E 1/2 ) of the complexes and reactivity was established.
34 citations
15 Jun 1998
TL;DR: In this article, the solvation of chromone has been investigated using three different combined Discrete/SCRF models (PCM/6-31G(d), PCM/AM1, and SM2/AM 1) in order to evaluate the reliability of the combined discretized/scruff models and investigate the effects of explicit water molecules on the free energy of solvation.
Abstract: The solvation of chromone has been investigated using three different combined Discrete/SCRF models. Four chromone–H 2 O complexes and one chromone–4H 2 O complex were obtained from geometry optimizations at the HF/6-31G(d) level. Three SCRF methods (PCM/6-31G(d), PCM/AM1 and SM2/AM1) were applied to such complexes in order to: (1) evaluate the reliability of the combined Discrete/SCRF models; (2) investigate the effects of the explicit water molecules on the free energy of solvation; and (3) analyze the characteristics of the different solvation sites of chromone. The results show that explicit solvent molecules exert a large influence on the free energy of solvation of a given molecular system providing some information about the solvation sites. Thus, the interaction of the carbonyl oxygen of chromone with the explicit water molecules is stronger than interaction provided by the ether oxygen, providing the complexes with the former interaction a more hydrophobic free energy of solvation than those with the latter. On the other hand, the comparison of the free energies of solvation for solutes with explicit water molecules in the first hydration shell and the free energies of solvation of the molecular system computed in an all-continuum approach reveals that the combined Discrete/SCRF models constitute a very reasonable strategy.
27 citations
TL;DR: In this article, a rationalization is suggested which can help organic chemists in realizing analyses of the relative stereochemistry of substituted cyclopentanes by proton NMR, through the coupling constants between vicinal hydrogens.
25 citations
TL;DR: Treatment with phosphatidylinositol-specific phospholipase C of rat osseous plate membranes released up to 90-95% of alkaline phosphatase, but a specific ATPase activity remained bound to the membrane, suggesting that the membrane-specific ATP enzyme activity present in osseOUS plate membranes, and alkaline phosphate, were different proteins.
22 citations
30 Jun 1998
TL;DR: For example, a recent study as discussed by the authors investigated the impact of notifying a parent of a portador of anomalia genetica on reacoes and sentimentos of criancas.
Abstract: O presente trabalho procurou conhecer, junto aos pais de criancas portadoras de deficiencia e/ou anomalias geneticas, qual o impacto causado pela noticia, suas reacoes e sentimentos. Participaram deste estudo dez (10) familias, que foram encaminhadas ao Ambulatorio de Genetica Medica do Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo para diagnostico e orientacao. Os relatos mostraram que o impacto emocional da noticia e grande, desencadeando reacoes diversas, entre elas choque e agressividade. Culpa, negacao e raiva sao alguns dos sentimentos vivenciados pelos pais. A noticia e dada quase sempre de maneira inadequada, dificultando a compreensao do diagnostico. Pode-se concluir que, independentemente do quadro clinico, os pais sofrem o impacto da noticia de que seu filho e portador de deficiencia e/ou anomalia genetica. O processo de sofrimento e agudo, passando os pais por um periodo de enlutamento pela perda do filho esperado.
21 citations
TL;DR: In this article, the electronic structure of chromone and those of its 2-hydroxy derivatives were studied by semi-empirical and ab initio molecular orbital methods, and the relative stability of compounds (2 ) and (3 ) was explained and the sites of acid, basic, nucleophilic and electrophilic attack were also determined.
Abstract: The electronic structure of chromone ( 1 ) and those of its 2-hydroxy ( 2 ) and 3-hydroxy ( 3 ) derivatives were studied by semiempirical and ab initio molecular orbital methods. Several electronic parameters show that the A-ring is an aromatic system, whereas the C-ring does not present conjugation. In the C-ring, the double bonds are located in the carbonyl group and between C(2)–C(3). These results were confirmed by comparison with geometries of chromone derivatives which were determined by X-ray diffraction data. The relative stability of compounds ( 2 ) and ( 3 ) was explained and the sites of acid, basic, nucleophilic and electrophilic attack were also determined.
01 Jan 1998
TL;DR: P-Nitrophenyl phosphate was the best substrate, but AMP, ADP, ATP and β-glycerophosphate also served as substrates, which may be of interest for practical applications.
Abstract: An extracellular alkaline phosphatase (EC 3.1.3.1) was purified from conidia of Humicola grisea var. thermoidea. The molecular mass of the purified native enzyme was estimated as 126 kDa by gel filtration. SDS-PAGE revealed a single polypeptide band of 63 kDa, suggesting that the native enzyme was a dimer of identical subunits. The pI of the enzyme was about 3.0. Optima of pH and temperature were 9.0 and 70 °C, respectively. In Tris-HCl buffer, pH 9.0, the enzyme was activated by MgCl2 and strongly inhibited by ZnCl2, CoCl2, Al2Cl3, HgCl2, EDTA and β-mercaptoethanol. In contrast, in glycine buffer and at the same pH the enzyme was activated by ZnCl2 and CoCl2, as well as by MgCl2. The enzyme was fully stable when incubated up to one hour at 65 °C without magne-sium labilized the enzyme incubated at 65 °C or 70 °C. p-Nitrophenyl phosphate was the best substrate, but AMP, ADP, ATP and β-glycerophosphate also served as substrates. The remarkable thermostability exhibited by the purified alkaline phosphatase of H. grisea may be of interest for practical applications.
TL;DR: The mycoparasite Trichoderma harzianum produces an alkaline proteinase that may be specifically involved in mycopcarasitism as discussed by the authors, and the authors constructed transformant strains of this fungus that overexpress this proteinase.
Abstract: The mycoparasite Trichoderma harzianum produces an alkaline proteinase that may be specifically involved in mycoparasitism. We have constructed transformant strains of this fungus that overexpress this alkaline proteinase. Some of the transformants were assessed for alkaline proteinase activity, and those with higher activity than the wild type were selected for further studies. One of these transformant strains produced an elevated and constitutive pbr1 mRNA level during mycoparasitic interactions with Rhizoctonia solani.
TL;DR: Three new nerves that connect the stomatogastric nervous system of honey bee larvae and pupae to the central nervous system and the foregut are observed, representing the initial step in caste differentiation.
Abstract: Progress in our understanding of polymorphic differentiation of female honey bee larvae into queens and workers required a re-evaluation of neuronal pathways potentially involved in transmitting information on food quality. This study presents new data on the anatomy of one of these pathways, the stomatogastric nervous system (SNS) of honey bee larvae and pupae. Scanning electron microscopy preparations demonstrated not only developmental changes in frontal ganglion structure, but also provided firm evidence for a hypocerebral ganglion in the honey SNS. In addition to previously described SNS nerves, the frontal, recurrent and esophageal nerves, and the frontal connectives, we observed three new nerves that connect the SNS to the central nervous system and the foregut. The first one is an unpaired connective nerve of the frontal ganglion to the anteromedial protocerebrum. The second consists of paired lateral branches of the recurrent nerve, and the third is a plexus of fine nervous branches associated with the pharynx. Lateral extensions of the newly described hypocerebral ganglion also make contact with the pharynx. Similar but smaller branches were also observed to originate from the esophageal nerves as they run along the foregut. The exact anatomical localization of the cardiostomatogastric nerves, which connect the SNS with the retrocerebral complex, could also be detected. The description of such new nervous connections will serve as a database for functional analyses on the role of the SNS in differential feeding responses of the honey bee larvae, representing the initial step in caste differentiation. J. Morphol. 236:139-149, 1998. © 1998 Wiley-Liss, Inc.
TL;DR: In this paper, the conformational preferences of each compound in the gas phase, aqueous solution and organic solution were determined using AM1, MNDO and B3-LYP/6-31G(d) calculations.
TL;DR: The exo‐1 mutant of Neurospora crassa produced and secreted pectolytic activities when incubated in the presence of pectin‐containing biological materials, indicating that these sugars induced the synthesis of pECTinases.
Abstract: The exo-1 mutant of Neurospora crassa produced and secreted pectolytic activities when incubated in the presence of pectin-containing biological materials. This study shows that polygalacturonase, pectate lyase and pectin lyase activities were induced in media supplemented with galactose or galacturonic acid, indicating that these sugars induced the synthesis of pectinases. Pectinesterase activity was undetectable. Polygalacturonase activity was better induced by galactose than by galacturonic acid. The reverse was true for lyase activities. The inducing effect of galactose and galacturonic acid seemed to be different: (i) a mixture of galactose and galacturonic acid synergistically increased the production of pectic enzymes, as compared to that in the presence of one of these sugars; (ii) the inducing effect of galacturonic acid was partially repressed by glucose; (iii) in contrast, the inducing effect of galactose, rather than repressed, was enhanced by the presence of glucose. Altogether, these data point out to a complex mechanism of regulation of pectolytic enzymes by pectin-containing organic substances.
TL;DR: In this paper, a metodologia qualitativa -metodo fenomenologico -is used to evaluate depoimentos da equipe de enfermagem that vivencia esta experience.
Abstract: Este trabalho se propoe a desvelar algumas facetas da experiencia de uma equipe de enfermagem que cuida de criancas com câncer nos plantoes noturnos. Para tanto, recorri a uma metodologia qualitativa - metodo fenomenologico - que me possibilita uma analise compreensiva dos depoimentos da equipe de enfermagem que vivencia esta experiencia. As convergencias dessas falas sao analisadas e possibilitam a identificacao de algumas unidades de significado que podem contribuir com subsidios para garantir institucionalmente as condicoes minimas de trabalho para equipe de enfermagem, bem como prepara-la para lidar com tais circunstâncias.
TL;DR: In this article, the authors studied the short-time dynamics of a three-state probabilistic cellular automaton with up-down symmetry similar to Ising models, and showed that it exhibits continuous kinetic phase transitions belonging to the Ising model universality class.
Abstract: We study the short-time dynamics of a three-state probabilistic cellular automaton This automaton, termed TD model, possess "up-down" symmetry similar to Ising models, and displays continuous kinetic phase transitions belonging to the Ising model universality class We perform Monte Carlo simulations on the early time regime of the two-dimensional TD model at criticality and obtain the dynamic exponent θ associated to this regime, and the exponents β/ν and z Our results indicate that, although the model do not possess microscopic reversibility, it presents short-time universality which is consistent with the one of the kinetic Ising model
TL;DR: In this article, the INDO 1/S and AM1 methods were used to carry out the calculations for the singlet states and those among the triplet states for the flavylium cation and anthocianidins.
TL;DR: Pectolytic enzymes from the hyperproducer exo-1 mutant of Neurospora crassa were purified and characterized, finding that galactose-induced pectinases are not affected by glucose repression, and these enzymes inactivated at 60°C.
Abstract: Pectolytic enzymes from the hyperproducer exo-1 mutant of Neurospora crassa are induced either by pectin or galactose. Galactose-induced pectinases, in contrast with pectin-induced enzymes, are not affected by glucose repression. Here, the pectolytic enzymes induced by galactose were purified and characterized. Extracellular pectolytic activities were separated into two main fractions. Pool I contained lyases, and a polygalacturonase (PG) copurifying as a complex of about 80 kDa (gel filtration). Pool II contained PG only. Under urea-SDS-PAGE the lyases and polygalacturonase from pool I migrated with an apparent MW of 56.2 kDa, and 34.3 kDa, respectively. PG from pool II exhibited an apparent MW of 44.7 kDa. Cell extracts contained PG free of lyase activities. Purified intracellular PG migrated (SDS-PAGE) as a single band of apparent MW of 31.5 kDa. All pectinases were glycoproteins (18.5–39% carbohydrate), with stability and optimum pH at 5–6 and 9–10 for PG and lyases, respectively. Temperature optima were 40–50°C, respectively. All enzymes were inactivated at 60°C, with a half-life from 1.5 to 5 min. Activation energy (Ea) values for extracellular and intracellular PG varied between 0.45 and 2.0 Kcal mol−1. Pool II and intracellular PG and lyases, exhibited a random mechanism of hydrolysis. Pool I PG exhibited an exo character.
TL;DR: In this paper, the authors study nonequilibrium phase transitions occurring in a probabilistic cellular automaton which describes one part of the immune system and show that the model belongs to the Ising universality class, supporting the up-down" conjecture.
Abstract: We study nonequilibrium phase transitions occurring in a probabilistic cellular automaton which describes one part of the immune system. In this model, each site can be occupied by three type of cells and the immune response under parasitic infections is described in terms of two parameters p and r. The local rules governing the evolution of this automaton possess \up{down" symmetry similar to Ising models. Performing Monte Carlo simulations on square and cubic lattices we verify that the model displays continuous kinetic phase transitions with spontaneous symmetry breaking. We present detailed simulations and analysis of the critical behavior. Our results indicate that the model belongs to the Ising universality class, supporting the \up{down" conjecture. c 1998 Elsevier Science B.V. All rights reserved
30 Dec 1998
TL;DR: The purpose of this study was to scale the seriousness of 68 clinical surgical illnessess by physicians and nurses through the magnitude estimation method.
Abstract: O objetivo deste estudo foi escalonar, por medicos e enfermeiros, a gravidade de sessenta e oito (68) quadros clinicos cirurgicos, atraves do metodo de estimacao de magnitudes. Os dados permitem concluir que: 1) os quadros clinicocirurgicos,
aneurismectomia de aorta, aneurismectomia cerebral e revascularizacao do miocardio, foram considerados os de maior gravidade, enquanto que os quadros clinicocirurgicos, adenoidectomia, amigdalectomia e curetagem uterina, os de menor gravidade em todas as escalas obtidas pelos diferentes metodos psicofisicos diretos e 2) a escala de razao de gravidade de quadros clinicocirurgicos e valida, estavel e consistente, pois o expoente obtido (0,74) atraves dos emparelhamentos de comprimentos de linhas e de forcas dinamometricas nao foi significativamente diferente do expoente predito (0,77) pela propriedade de transitividade das escalas, ou seja, daquele obtido nas tarefas de calibracao por Faleiros Sousa (1)
30 Jun 1998
TL;DR: In this paper, a comparative study of the condicoes psicologicas and a qualidade de vida of pacients submetidos a transplante de medula ossea (TMO) is presented, visando uma compreensao dos recursos disponiveis for adaptacao and o ajustamento psicossocial.
Abstract: O presente estudo tem como objetivo avaliar as condicoes psicologicas e a qualidade de vida de pacientes submetidos ao transplante de medula ossea (TMO), em dois momentos de recuperacao – adaptacao inicial e adaptacao a longo prazo – visando uma compreensao dos recursos disponiveis para a adaptacao e o ajustamento psicossocial
TL;DR: In this article, the stability of non-autonomous retarded functional differential equations using the theory of dichotomic maps was studied and the results about asymptotic stability of the equation were established.
Abstract: This paper deals with the study of the stability of nonautonomous retarded functional differential equations using the theory of dichotomic maps. After some preliminaries, we prove the theorems on simple and asymptotic stability. Some examples are given to illustrate the application of the method. Main results about asymptotic stability of the equation \(x'(t) = - b(t)x(t - r)\) and of itsnonlinear generalization\(x'(t) = b(t)f(x(t - r))\) are established.