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Seções de choque diferenciais absolutas para o espalhamento elástico de elétrons de energias baixas e intermediárias por moléculas poliatômicas em fase gasosa
(Universidade Federal de São Carlos, 2002-05-27)
Homem, Manoel Gustavo Petrucelli
;
Iga, Ione
;
https://lattes.cnpq.br/8934634344275868
;
https://lattes.cnpq.br/2059356773212608
In this work we report absolute elastic differential cross sections (DCS) measurements for electron collisions with OCS, CO2, CH4, NO, N2O, CHF3 e C2F6 molecules in gas phase. The measurements cover the angular range from 10o to 130o and energy range between 50-800 eV. Crossed electron beam-molecular beam geometry is applied to measure the relative intensity of the scattered electron as a function of the scattering angle. The scattered electrons are energy-filtered by a retarding-field energy selector. The recorded scattering intensities, as a function of the scattering angle, are converted into absolute elastic DCS s using the relative flow technique. Additionally, this work reports the development of a low energy electron scattering spectrometer (E<100 eV). In this spectrometer a new technique, a magnetic angle-changing device has been constructing to extend the measurements to backward angles (up to 180o). However, the application of this technique needs more systemization. Results of DCS s using the magnetic angle changer are reported only for the argon atom for the energy of 30 eV up to 120o, showing the future prospect of this technique. In the other hand, using the new spectrometer, DCS s data are reported for the CHF3 molecule for electron energies from 10 to 30 eV up to 85o scattering angle. In summary, several results of absolute differential cross sections for the elastic electron scattering are reported to several molecular targets. The comparison between our measured data and theoretical calculation using an optical potential to represent the electron-molecule interaction as well as other available experimental data in the literature shows good agreement. Our study has shown the significant role played by the absorption effects on the calculated cross sections in the intermediate energy range.
Reintrodução de cervos-do-pantanal (Blastocerus dichotomus): uso do espaço e área de vida dos animais
(Universidade Federal de São Carlos, 2002-05-27)
Figueira, Cassio José Montagnani
;
Pires, José Salatiel Rodrigues
Eleven adult marsh deers derived from the Porto Primavera population were reintroduced in two areas of São Paulo State at the end of 1998: Continental farmland (Colômbia - North São Paulo) and Jataí Ecological Station (Luís Antônio - Northeast São Paulo). The animals were radio tagged and daily monitored to survey space utilization and home-hange. Six marsh deers were reintroduced at Continental farmland (two males and four females) and surveyed from October until December 1998. The animals came to death in one to thirty days after the releases and a female disappeared in twenty days after its release probably because hunters activity. The surveys about space utilization and home-hange were unfeasible at Continental farmland by the limited survival of the animals. Five marsh deers were reintroduced at Jataí Ecological Station (two males and three females) and surveyed from December 1998 until April 2000. Two females came to death nearly two and four months after the releases and the rest remained alive during the study time. The survival of the animals at Jataí Ecological Station allowed surveys about home-range and space utilization in that area.
Entre o peixe e o dendê; etnoecologia do povo dos Marimbús (Chapada Diamantina - BA)
(Universidade Federal de São Carlos, 2002-05-28)
Moura, Flávia de Barros Prado
;
Nordi, Nivaldo
;
https://lattes.cnpq.br/8168865557947289
;
Marques, José Geraldo Wanderley
This study documents traditional ecological knowledge by a human population living in Chapada Diamantina, Northeast Brazil. The field work was carried out from June 1998 to May 1999 and included: open-ended interviews, structured interviews, direct observation, questionnaires and tours guided by fishermen. Fish and plants species were collected and taxonomically identified. The consistence of fishermen´s knowledge was observed through compared cognition tables. Local knowledge related to spatiotemporal distribution of fish, ethology, feeding behavior and fish reproduction are fundamental for fishing activities. Plant use is extensive: 131 species of plants medicinally, 69 species for food, 44 for firewood, 38 for house building, and 23 for fishing practices. 72 products from 52 species of animals were reported to be used for prevention and cure 40 physically or spiritually derived illnesses. Most of the medicines (55 %) are derived from by-products of animals normally hunted for food intention. Traditional knowledge about fish species was gathered and proved to be consistent with data from scientific literature. Local knowledge is fundamental for fishing activities and should be taken into account in the planning of sustainable management for the area, which has been set aside by government as an APA (Environmental Protection Area).
Interações de agentes naturais no controle populacional de Spodoptera frugiperda Smith (1797) (Lepidoptera:Nocturidae) em milho (Zea mays)
(Universidade Federal de São Carlos, 2002-05-28)
Mantrangolo, Walter José Rodrigues
;
Dias, Angélica Maria Penteado Martins
;
https://lattes.cnpq.br/8637344058859147
It was evaluated the possible interactions among the following agents of natural control of Spodoptera frugiperda (Lepidoptera: Noctuidae): Campoletis flavicincta (Hymenoptera: Ichneumonidae), the Nuclear Polyhedrosis Virus (NPV - Sf) and different maize genotypes with different levels of genetic resistance [Resistant exotic parental Zapalote Chico (ZC) (Zea mays), the adapted parental BR 105, and four semi-exotic populations, with different percentages of gene introgression: 50% of ZC + 50% of BR 105 (or simply F1), 25% of ZC + 75% of BR 105 (backcross 1 or simply BC1), 12,5% of ZC + 87,5% of BR 105 (or BC2) and 6,25% of ZC + 93,75% of BR 105 (or BC3)]. The incubation period of the eggs of C. flavicincta was approximately 48 hours. Most of the caterpillars of S. frugiperda contained more than one eggs of the parasitoid. However, 24h after eggs eclosion, it was observed the presence of only one developed larvae in the same caterpillar. Probably there is a competition among newly hatched larvae and through physical attack only one survives. Females of the parasitoid laid more eggs in healthy caterpillar than in infected one, when they did not have choice option. When in contact with healthy caterpillars and infected by NPV - Sf at the same time, there was not difference in the number of deposited eggs, probably because the female could not discriminate between of healthy or NPV infected host. In olfactometer test, healthy S. frugiperda larva and corn leaf attracted 50% of the C. flavicincta females. In the treatment with infected caterpillars and your leaf, they were attracted 32,1% of the females. Where just had leaves, that value was of 14,3% and the witness, without any scent source, it attracted only 3,5% of the females. To discriminate healthy hosts of having infected can minimize the negative impact of NPV - Sf on the parasitoids. Increase of the size of the caterpillar implicates in a reduction in the efficiency of the virus. The united use of virus and parasitoid in laboratory increased the mortality of caterpillars of S. frugiperda in laboratory, when compared with the treatment where was just used the virus. As larger the interval of time between parasitism and infection, larger the survival of C. flavicincta. The previous infection with NPV - Sf reduced the emergency of the parasitóide, mainly in caterpillars infected in the 2nd and 3rd days of life. Not only originated females of caterpillars infected by the virus they were capable to transmit the pathogen for healthy caterpillars, but also those females initially exempt of the virus, but that were coupled with males originating from of infected caterpillars. In laboratory, the genetic materials didn't indicate significant differences in the biological parameters (efficiency of parasitism, weight of healthy caterpillars and sponged, weigh of the pupas, duration of the phase pupal and sexual reason of the host and of the parasitoid). In the field smallest number was collected of caterpillars of size 3 and any caterpillar of size 4 in ZC, besides smallest number of caterpillars of S. frugiperda, of pupae of the parasitoid and where the damage level was smaller, indicating that there was effect of that material.
Distribuição e abundância de peixes de corredeiras e suas relações com características de hábitat local, bacia de drenagem e posição espacial em riachos de Mata Atlântica (bacia do rio Maquiné, RS, Brasil
(Universidade Federal de São Carlos, 2002-05-29)
Becker, Fernando Gertum
;
Verani, Nelsy Fenerich
;
https://lattes.cnpq.br/1862746100743391
The relationship between fish, local habitat, catchment characteristics spatial position in riffles of the Maquiné river basin (RS, Brazil) was studied. Results were discussed considering present and historical states of conservation of the basin, which was determined from Landsat TM5 images. Fish data were obtained from qualitative sampling and quantitative sampling. The later involved standardized kick-sampling in 24 riffles. Sampling occurred seasonally from August 1999 to June 2000. A total of 72 fish species occur at the Maquiné river basin. Only 3 species occur at the headwaters, 1 at the slope of the Serra Geral and 68 from valley bottoms to the river mouth. Among the later, 20 occur exclusively in valley bottom stream sections and not in Coastal Plain habitats. From these, 8 benthic riffle species were investigated for relations with habitat and catchment characteristics. The spatial pattern of assemblage variation allowed the description of four assemblage types: a)assemblages dominated by Hemipsilichthys spp; b) with high relative abundance of Hemipsilichthys spp, but other species being also abundant, c) with intermediary total abundance, dominated by R. aequalicuspis, E. bilineatus and C. pterostictum; d) with low total abundance, dominated by R. aequalicuspis. Assemblages were seasonally persistent and proportional abundance was stable. Although local habitat characteristics have significantly contributed to explain variation in the data, the observed patterns reflected the control of catchment characteristics over local habitat and fish assemblages. Although spatial position was important both at the individual stream and basin scales, assemblage characteristics were also related to catchment area. The state of conservation at the catchment scale did not present evident relationships with fish assemblage characteristics and some hypothesis explaining this finding are discussed. The present process of vegetation recovery, the relatively high number of species and the biogeographic situation of the Maquiné basin indicate that it should be contemplated in conservation programs. Theregion is promising for investigating how lotic ecosystems respond to landscape recovery in their catchments.
Fragmentos de florestas Atlânticas no Rio Grande do Norte: relações estruturais, florísticas e fitogeográficas
(Universidade Federal de São Carlos, 2002-06-03)
Cestaro, Luiz Antonio
;
Soares, João Juares
;
https://lattes.cnpq.br/6093800182799882
The knowledge about Brazilian Atlantic forests in its northerm limit of distribution, in the transition to Caatingas, is will very scarce, mainly in the Rio Grande do Norte State, were the small and rare forest fragments still existing are almost totally ecological and phytogeographically ignored. We suppose that this fragments occurs on sandy, dystrophic and deep soils and that the rain gradient is the main factor to determinate different patterns of vegetation types in the east-west direction. The aims of this work are to characterize floristic and structurally the tree layer of four forest fragments ant to determine its relationships with the nearest phytogeographical provinces. Three semi-deciduous and one deciduous fragments were analyzed, all near of the Natal City, almost perpendicular to the coast. Two fragments, a semi-deciduous and the deciduous, were stretched in two parts according to the relief differences. The point-centered quarter method was used to sample, in the six areas, the standing and living trees with stem perimeter at 1,3 m heigth equal or superior to 10 cm. To each tree were considered: the species name, height estimated, stem perimeter(s) and the distance to the point. Data were worked at spreadsheets to obtain total density, specific and total basal areas and relatives frequency, density, dominance, importance value and dominance value, H'diversity and J' equability were obtained to each area. To a semi-deicuous forest and to the deciduous one the proportion of species connected to different phytogeographical provinces was obtained. The structure and the floristic composition of the areas were compared. The structure, by means of tree heights, stem diameter and basal area and the floristic composition, by means of Sorensen and Czekanowski similarity indices. Cluster analysis (UPGMA) was used to classify the areas. In all areas 117 species were observed, being 89 in the semi-deciduous forest and 66 in the deciduous forest. Fabaceae and Mytaceae are the richest families. The tree densities vary from 2403 to 1526 individual/ha. The semi-deciduous forests generally are tallest and have a biggest basal area (from 22,29 to 39,84 m2/ha) than deciduous forest, with a basal area of 15,87 m2/ha. The diversity vary between 2,8 and 3,27 nat/individual and the equability between 0,77 and 0,82 to the semi-deciduous forests, while to the deciduous forest the H' values are 3,19 and 3,26 nat/individual and the j' values are 0,79 snf 0.86. Two floristic groups were obtained by classification. One compounded by semi-deciduous forests and another with the deciduous one. The semi-deciduous forests have the highest proportion of species associated to the Atlantic province and a high proportion of wide distribution. Neotropical species, especially in the gallery forests of the Cerrados. Few species are shared with the Caatingas. The deciduous forest has similiar proportions of species from Atlantic, Caatingas provinces of wide distribution species, being considered as transitional vegetation between the first two provinces. The rain gradient determines the distinction of semi-deciduous forest from the deciduous one, while the edaphic and geomorphologic factos are responsible by different semi-deciduous forest types. The floristic and structural variability observed in a semi-deciduous fragment is associated to the relief and soil variations, being the upper area a transition to the coastal "tabuleiros" savannas, while the lower area, a transition to the gallery forest. The deciduous forest presents low structural internal variability, but with typical species of dry forests in the upper area and typical species of Caatingas in the lower area. The results point out the complexity of the vegetational mosaic in the transitional area between Atlantic and Caatingas provinces in the Rio Grande do Norte State
Pré-condicionamento em sementes de Cassia excelsa Schrad
(Universidade Federal de São Carlos, 2002-06-05)
Jeller, Helma
;
Perez, Sonia Cristina Juliano Gualtieri de Andrade
;
https://lattes.cnpq.br/9973185407856723
Cassia excelsa is a woody species commun in cerrado and srubland of brazilian northeast, known by cassia-do-nordeste . It could be used in landscape place and due to small size is used in street arborization, and could be recommended to recomposition of degradated areas. The aim of this work was to extend the knowlege about the ecophysiological behaviour, with the the study of priming in seed germination. For this purpuse, it was evaluated the effects of water and PEG solutions (-0,2; -0,4 and -0,6 MPa) in uptake process at 20ºC. The effects of the drying and storage after priming; the answer under water, thermic and salt stress after priming was also verified. Besides it, the priming effects in seed viability and vigor under optimal conditions (27ºC) were observed by eletrical conductivity, accelerated aging and submersion tests. In all the tests was used 4 replicates of 25 seeds, with daily evaluation, and considered germinated when radicle was > 2 mm long. According to the results of uptake curve of Cassia excelsa seeds was observed that with the decreased in the osmotic potential increase the time necessary to priming. At optimal temperature (27ºC) the answer of primed seeds was efficient if water or PEG solution at -0,2 MPa was used, and this answer is maintened after 15 days of storage at 5ºC, but the drying of the seeds overcome the positive effects of the pré-treatment. The priming in water or in PEG solutions increased germination percentage under water, salt and thermal stress, however, with restriction to germination rate. The electrical conductivity of the primed seeds in water or in PEG was reduced, constrated to the non-primed seeds, and increased in the dried seeds after the priming. The priming in water or PEG was efficiente to overcome the deteriorative process occurring in aging, in dehidrated and in moist seeds, after priming. The seed vigor of primed seeds was no affected by submersion in distilled water during diferents time periods.
Caracterização estrutural e funcional de hemoglobinas de skua, Catharacta maccormicki
(Universidade Federal de São Carlos, 2002-06-05)
Landini, Gustavo Fraga
;
Schwantes, Arno Rudi
;
https://lattes.cnpq.br/1515297609478949
Hemoglobin samples of Catharacta maccormiki (Skua), an Antarctic bird, collected in winter and in summer were studied. Starch gel eletrophoretic pattern hemoglobin oxygen affinities on blood and stripped hemoglobin; influence of organic phosphates that may change affinity and level of those intra-erythrocytic phosphates were analyzed. No differences were found in Hb-O2 affinities for samples collected in winter and in summer, which leads to believe that migration (Winter) is not a factor for the oxygen affinities in blood. Bohr effect for both situations was practically the same (Φ= -2,1), indicating normal Bohr effect. The 5 samples show a electrophoretic pattern of two components, so, no evidence of intra-specific variation was found. For the stripped hemoglobin the P50 values were inferior to the ones obtained for whole blood, showing a higher affinity for the hemoglobin to oxygen in the absence of possible modulators. The Bohr effect in the alkaline side (pH 7 8) was normal (Φ = -1,9), and in the acid side it was reverse, characteristic of birds hemoglobin. The influence of organic phosphates that could affect oxygen affinity was also tested. 2,3-diphosphoglycerate (2,3DPG) and inositol hexaphosphate (IHP) were added to the stripped hemoglobin in order to test them as modulators. Negative hemoglobin oxygen affinity modulation was observed after addition of both phosphates. IHP is more effective than 2,3DPG. For animal collected during winter only the GTP was present in its erythrocytes, while the summer ones ATP was found instead of GTP. No differences was found in the concentration of inositol penta and hexaphosphsphate in samples collected in the two seasons. No 2,3DPG were found in any sample.
Diagnóstico ambiental integrado e subsídios ao estabelecimento de metas de qualidade da água na Bacia Hidrográfica do Rio Jaboatão (PE)
(Universidade Federal de São Carlos, 2002-06-11)
Souza, Antonio Donizetti Gonçalves de
;
Tundisi, José Galizia
;
https://lattes.cnpq.br/5730659239785432
;
https://lattes.cnpq.br/6166513254973886
The main subject of the present work was to realize integrate environmental study in the Jaboatão River, a densely urbanized and industrialized basin, and to offer subsidies to the establishment of water quality goals. Eight sampling points were established and was sampling monthly during period from September/97 to February/99. The following variables were analyzed: temperature, pH, turbidity, conductivity, chlorine, alkalinity, dissolved oxygen, biochemical oxygen demand, fecal coliforms, nitrate, total phosphorus, total solids, Ca, Mg, Na, K and Fe. The sediments were collected at four sites being analyzed the metals Cd, Pb, Cu, Cr, Fe, Mn, Ni and Zn. Water quality historical data (1986-1996) were also recovered and analyzed. The following thematic maps were produced: land uses, legal protection, hydrography, municipal limits, geology, soils, water withdrawals and industrial sources of pollution. Based on maps of the legal protection areas, water withdrawals and industries, regions with water uses restrictions were delimited. Within these regions groups of water bodies were established using guidelines for protection and recovery and proposing water quality classes based on CONAMA resolution 20/86. The results demonstrate a condition of environmental degradation as attested to by several water quality variables analyzed. In the stations representing urbanized areas, the worst water quality conditions were found, especially in the summer period, resulting from industrial and domestic effluents. The critical variables were dissolved oxygen, fecal coliformes, and total phosphorus, placed the area within class 3 and 4 according CONAMA resolution 20/86. Water use regulation was proposed as a useful tool in beginning discussing of water quality goals according classification system proposed by the CONAMA resolution 20/86. The approach presented in this study can be used as a subsidy by public agencies, stakeholders and citizens responsible for establishing guidelines and effective measures for watershed protection and recovery.
Trabalhando pelo sucesso escolar: as vivências de uma professora em seu primeiro ano de atuação na escola pública.
(Universidade Federal de São Carlos, 2002-06-12)
Silveira, Maria de Fátima Lopes da
;
Lima, Emília Freitas de
This work is orderly following this question: How to configure the professional learning of the teacher in the beginning of the carrier, in attempt to overcome the scholar failure of second grade students of the public elementary school? The research started beginning in 1999, during my first experience as teacher in the school in São Carlos-SP-Brazil. In this work, between the learning, is possible to detach: the attribution of the meanings to the theoretical references getting during the process of the fundamental development, and how to translate to the professional practice engaged with the scholar success; the construction of the teaching process related to the reading and writing (Ferreiro, 1995).
Ecologia da comunidade aquática de um riacho de 1ª ordem da Mata Atlântica: relações entre variáveis estruturais e bióticas em uma reserva de biosfera tropical
(Universidade Federal de São Carlos, 2002-07-05)
Vilella, Fábio Silveira
;
Hartz, Maria
;
Barbieri, Geraldo
This study was developed in arroio Carvão, a 1ª order stream at the Maquiné watershed, in the southern part of Atlantic Rain Forest, Brazil. The headwaters are within the Serra Geral Biological Reserve, a conservation unit that is a regional biodiversity core area of the Atlantic Forest Biosphere Reserve. The research was developed to identify the role of physical and chemical variables of the environment and the interactions of phoresis between species as elements that influence community structure in the stream. The results indicate the existence of a hierarchical relationship between the environmental variables and its influence on the community structure. It also reveals that morphological features and adaptations of the fauna to the lotic environmental pressure could turn highly elaborate and efficient, allowing the animals to neutralize or even transpose the environmental pressure. Phoresis, a non-negative form of interaction between species, represents an alternative way for animals morphologically less adapted to the lotic system, to colonize and establish on more favorable places in the stream. It is also discussed the evolutionary significance of phoresis.
Ruídos e processos quânticos fundamentais em íons aprisionados e ondas propagantes
(Universidade Federal de São Carlos, 2002-07-22)
Serra, Roberto Menezes
;
Moussa, Miled Hassan Youssef
;
https://lattes.cnpq.br/7828776012924524
;
https://lattes.cnpq.br/2538824540800669
In this work we present a proposal protocol for engineering arbitrary motional states of trapped ions.Our scheme is based on both techniques of quantum state sculpture and projection synthesis. Next, we investigate the decoherence process in ion traps due to the polarization of the residual background gas. Our results are compared with experimental data round in the literature. We also introduce a scheme for probing the tunneling mechanism os a single ion trapped in a double-well electromagnetic potential. The tunneling process is characterized through the probability for a fluorescence measurement of electronic ground state of trapped ion. Finally in the running wave domain, we present a protocol for the teleportation of an entangled of zero- and one- photon states of the running wave field. We consider the process of photoabsorption in the linear and nonlinear optical elements required to achieve 100% of probability of sucess in the ideal case.
Bases teóricas, metodologia de elaboração e aplicabilidade de indicadores intra-urbanos na gestão municipal da qualidade de vida urbana em grandes cidades: o caso de Belo Horizonte
(Universidade Federal de São Carlos, 2002-07-25)
Nahas, Maria Inês Pedrosa
;
Oliveira, Haydée Torres de
;
https://lattes.cnpq.br/5458113597909705
;
https://lattes.cnpq.br/7384788149860065
Impactos das atividades antrópicas sobre a comunidade dos macroinvertebrados bentônicos do Rio Cuiabá e Várzea Grande - MT
(Universidade Federal de São Carlos, 2002-08-02)
Lima, João Batista
;
Gessner, Alaíde Aparecida Fonseca
;
https://lattes.cnpq.br/8465752836529703
The benthonic macroinvertebrates community has been widely used to evaluate the effects of the anthropic activities on the aquatic ecosystems, but in brazil the studies on the taxocenosis of the macroinvertebrates are scarce, particularly for large rivers crossing metropolitan regions and therefore under urban impacts. The distribution of the macroinvertebrates as well the physical and chemical parameters of the water was studied along the Cuiaba River, between the cities Varzea Grande and Cuiaba. It is noteworthy that these two cities throw out domestic sewage and industrial effluents into the river. The study was conducted during the periods of rainy and dry seasons in the years of 1999 and 2000. During this time the closing of the storage dam of Manso River was completed. This river is one of the main affluents of the Cuiabá River, upstream to the studies region. The sampling was made at six sites in both margins using artificial substrates exposed during six weeks. The resultes shoed differences in the taxocenotic structure of the macroinvertebrate community, and in the physical and chemical parameters of the water. These differences were related to the urban impact and to the closing of dam. The left margin in station 1 has been the best distribution standard of benthonic macroinvertebrates in relation of the others places, it was reflected by the indices of diversity. Oligochaeta and Chironomidae larvae were dominants along the river, however Chironomidae was more abundant in dry seasons and Oligochaeta in rainy seasons.
Caracterização de sistemas varistores a base de SnO2-MnO2
(Universidade Federal de São Carlos, 2002-08-02)
Orlandi, Marcelo Ornaghi
;
Leite, Edson Roberto
;
Longo, Elson
;
https://lattes.cnpq.br/9848311210578810
This work focussed on the effect of addition of Nb2O5 on the electrical and microestructural properties of SnO2-MnO2 based ceramics. It was also studied the effect of heat-treatments in a oxygen-rich atmosphere in these properties. The parent system was 99,5% SnO2-0,5% MnO2 in molar ratio, a dense system that did not present non-ohmic behavior. The addition of Nb2O5 on this system promoted an increase on the charge carrier number in the SnO2 matrix and, then, varistor properties were observed. Otherwise, the upper doping level, 0.25% mol of Nb2O5 system showed an higher porosity, due to the decrease on the thermal sintering properties, that depleted the varistor characteristic of this system. A detailed study on the electrical properties were performed using impedance spectroscopy and the obtained results showed that Nb2O5 tends to form an electronic trapping level between the valence and the conduction bands, modifying the potential barrier properties formed in the grain boundaries region. In order to explain the obtained results, it was proposed a parallel equivalent circuit model, based on the grain boundaries contributions to electrical properties. Heat-treatments under oxygen-rich atmosphere did not changed the observed electrical properties in the systems, due to the presence of numerous secondary phases (rich in oxygen and manganese), localized in triple points in the grain boundaries. It is pointed the there is a oxygen local enrichment in these phases, not significantly altering the observed macroscopical electrical characteristics in the analyzed systems.
Gastrópodes e outros invertebrados bentônicos do sedimento litorâneo e associados a macrófitas aquáticas em açudes do semi-árido paraibano, nordeste do Brasil
(Universidade Federal de São Carlos, 2002-08-08)
Abílio, Francisco José Pegado
;
Gessner, Alaíde Aparecida Fonseca
;
https://lattes.cnpq.br/8465752836529703
The Northeastern region in Brazil is characterized by long dry seasons, and the dams are very important to the people living in this region. In this work two dams in the semiarid of Paraiba State were studied to evaluate the quality of the water for human consumption, through the analysis of the benthonic community in the sediment and associated to aquatic macrophytes. The two dams studied are under different influences, one of them called Bodocongó receive organic wastes discharges from the city of Campina Grande, and is characterized as a hypertrophic system due to the high organic content in its waters. The other dam, called Taperoá II, is subjected to drought after long dry seasons. During the time that the present study was conducted, the dam was subjected to intense drying process, remaining only small pools. As a consequence, the waters of these poolls exhibited high values for the salinity and for the electrical conductivity. Even under different influences, the two dams exhibited similar benthic communities, characterized by a poor diversity of taxonomic groups, with predominance of gastropods, especially Melanoides tuberculata (Thiaridae), representing 80% of the total community. Further studies in the laboratory showed that M. tuberculata possesses high resistance to long periods of desiccation, with the survivors possessing high reproductive capacity that could cause the predominance of this species.
Hematologia, bioquímica do sangue, parasitologia, microbiologia, algas epizoárias e histopatologia de Phrynops geoffroanus (Schweigger, 1812) (Testudinata, Chelidae), expostos a diferentes influências antrópicas no rio Uberabinha, Minas Gerais
(Universidade Federal de São Carlos, 2002-08-14)
Brite, Vera Lucia de Campos
;
Rantin, Francisco Tadeu
;
https://lattes.cnpq.br/3546242299713690
Comparative studies of morphometry, microbiology, hematology, blood biochemistry, histopathology, hematozoary research, ectoparasites and epizoary algae were performed between two subpopulations of the freshwater turtle Phrynops geoffroanus captured in two areas of the Uberabinha River. One area drains regional agriculture (18º58'35 S and 48º17'11 W), while the second is predominantely urban (18º5'10 S and 48º18'09 W). From December, 1999 to January 2001, field and laboratory work were accomplished characterizing the two areas as to the geographical relief, the plant life on the river margins, the air temperature and relative humidity, microbiology and several physical-chemical parameters of the water and residues of organochlorine (agricultural chemical) from the river sediment. To test differences between the two areas, climatic data, twelve physical-chemical parameters and water instantaneous speed were analyzed using the Wilcoxon test at a 5% significance level. Significant differences in the relative humidity of the air, total dissolved solids, suspended solids, electric conductivity, temperature, transparency, nitrites and turbidity of the river water were all verified. The urbanized area presented smaller conservation in the margins vegetation, lowest air relative humidity, water with larger concentrations of total dissolved solids, suspended solids, nitrite, larger electric conductivity, smaller transparency, larger turbidity, larger variety of microorganisms and organochlorate residues, being that the transheptachlor, endossulfan and atrazine indexes were higher in the agricultural area.The different human-related influences on soil use were reflected in the composition of the flora on the river s margins and in the aquatic ecosystem, resulting in high levels mainly of phosphate, nitrogen, atrazine, transheptaclor, endosulfan and BHC, as well as water bacterial contamination. The fifty eight P. geoffroanus were captured in January of 2000, being 16 males and 16 females coming from the urban area and 12 males and 14 females from the agricultural area. To collect the Phrynops two funnel traps were used containing fish, chicken viscera and bovine heart as bait. The Phrynops were transported to the Reptiles Section at the Federal University of Uberlândia where they were sexed, marked individually and housed in concrete tanks. The ectoparasites and samples of the algae attached to the shells were collected and preserved. Blood samples were drawn for the glicemia determination. The morphometric data and the blood sample for hematozoary investigations together with hematological and biochemical blood analyses were also obtained from the turtles. Later, three males and three females from each subpopulation were sacrificed by decapitation for macroscopic analysis of the organs and histopathological studies. All the blood tests were performed during the summer. Analysis of the 15 morphometric characters and of the body mass data (ANOVA and ACP, 5% significance level) evidenced an accentuated sexual dimorphism; however, the different environmental conditions to which the two subpopulations were exposed didn't interfere in the size or in the form of the turtles. The microbiological analysis of the samples collected from the oral cavity, cloaca and the neck folds showed that the subpopulation from the urban area had a larger proportion of microorganisms in relation to that of the agricultural area (x2 = 31,0; P < 0,001). There were no significant differences among the proportions of microorganisms on body parts in relation to the geographical areas (x2= 0,017; P > 0,05). In both sample the oral cavity was the most infected (x2= 1,5897; P < 0,05). In the two subpopulations, the number of species of isolated microorganisms in the turtles was superior to the number of species found in the water of the river, with a few differences in the urban area. Although in this area a larger diversity of microorganisms, in the water and in the turtles, was found. A higher percentage of occurrence of the alga Basicladia chelonum, in the turtles shells was verified in the urban sample (43,8%) in relation to the agricultural sample (30,8%). Hemogregarine intraeritrocitary gametocytes were found in 27,6% of blood smears from P. geoffroanus, with a larger occurrence in the urban area. Ectoparasitism by leeches (Placobdella bistriata) was verified only in specimens from the urban area, and of the nine, six turtles were also infected by hemogregarine. Among the P. geoffroanus sacrificed, specimens from the agricultural area presented smaller amounts of fatty reserve tissue, more compact skeletal muscles, a more strong red color and dilation of some lung alveoli, indicating more physical activity compared with those from the urban area. The turtles from the urban area presented larger alterations as evidenced by the histopathological analysis, such as: discreet edema in the encephalon and the heart; cartilaginous formation in pulmonary alveolus and focal pneumonia; liver, pancreas, splein, kidney and stomach with inflamatory infiltrate and suggestive trematodes granulomas; hemossiderose in the liver and spleen. The hematological and biochemical data from the blood analysis were analyzed by analysis of variance (ANOVA, at a 5% significant level) for hypothesis testing and a difference of averages test (Tukey s test) to verify differences among the averages. Significant differences in relation to sex were obtained in 50% of the blood parameters (leucocyte numbers, eosinophyle percentages, hemoglobin, iron, phosphate, medium corpuscular hemoglobin, medium corpuscular hemoglobin concentration, prothrombin time, fibrinogen, ionized calcium, total proteins, albumin, alpha 1, alpha 2, gamma globulin, cholesterol high density lipoprotein and very low density lipoprotein, triglyceride, creatine kinase, gamma glutamil transferin, amilasys, lipase, uric acid, chloride and magnesium). In relation to the two geographical areas, 88% of the parameters were statistically significant (eritrocyte numbers, leucocytes, eosinophils, monocytes, heterophils, azurophils, hemoglobin, hematocrite, medium corpuscular hemoglobin and all the biochemical parameters, except to clotting blood). For the interaction area-sex analysis, 16% of the variables were significantly different (medium corpuscular hemoglobin, medium corpuscular hemoglobin concentration, leucocytes number, alkaline phosphatases, uric acid, beta globulin, iron and magnesium) between the two samples. The impact due to human intervention in terms of the different soil uses apparently caused environmental degradation interfering in most of the hematological and biochemical blood parameters between the two turtle subpopulations of the Uberabinha River. That, associated with the histopathological results, parasitological and the microbiological findings indicates that the environmental conditions, especially those related to the aquatic ecosystem, interfered in the physiology and could compromise the health of these turtles. Although the reference intervals of hemogram, electrophoresis and biochemical blood parameters used in the present study are important tools in the health control and diagnosis animal of diseases, they should not be considered as standard for this species, whose geographical distribution is wide, inhabiting ponds, streams and rivers with very diversified hidrogeochemical characteristics. Keywords: Phrynops geoffroanus, environmental contamination, morphometry, bacteria, epizoary algae, parasite infestation, hematology, histopathology, clinical biochemistry.
Análise qualitativa e quantitativa dos danos ambientais do município de São Carlos (SP) com base em instrumentos jurídicos
(Universidade Federal de São Carlos, 2002-08-19)
Cintra, Roberta Hehl de Sylos
;
Santos, José Eduardo dos
;
https://lattes.cnpq.br/8533387365058570
The public instauration and registration of environmental damages in the local landscape became a fundamental tool to collect information with easiness and reliability. Qualitative and quantitative analysis of the environmental damages was accomplished in the municipal district of São Carlos, SP, based on the organization and analysis of a database contemplating the juridical instruments established to the State public prosecution service, in the perspective of a diagnosis and of the environmental quality of the local landscape in terms of the relationship among the environmental damages and the current development trajectories. It was organized in a database 326 Administrative Procedures and 22 Public Civil Actions, totaling 348 prosecution registrations of environmental damages, in the period regarding 1991-2000. The environmental damages were classified in nine types, being deforestation the one of larger occurrence in every year and along the study period. Of the total number of deforestation 82,9% is related with areas smaller than five hectares, with prevalence of the performance of natural persons in relation to legal entities. It corresponds to 9,8% of the deforested total area, being equal to 110,35 hectares. The remaining 17,1% are associated with areas larger than five hectares embracing 90,2% of the deforested total area, being equal to 1013,27 hectares. The 217 registrations of environmental damages in the period from 1991 to 2000 determined a total loss of 1121,62 hectares of the vegetation component of the local landscape. In a rude estimate this total corresponds to the medium losses of 5,91 ±4,14 ha/occurrence and of 112,36 ± 91,73 ha/year of deforested area. The occurrence of environmental damages in Permanent Protection Areas, in number and in extension of deforested area, it is basically associated to the net road and to the riparian vegetation of the local watersheds. This process evidences the compromising of the environmental quality of the water resource, and landscape areas of hills and hillsides, in terms of the habitat loss and of the associated biodiversity. These results doesn t correspond to the real scenery of the local landscape conditions, once the environmental damages were not registered in your totality. It is fundamental the interaction among the information registered by the fiscal organs and those responsible ones by the elaboration and application of the guidelines for local development.
Estudo da influência de baixos teores de platina em catalisadores Ni/γ-Al2O3 nos processos de reforma a vapor, oxidação parcial e reforma oxidativa do metano
(Universidade Federal de São Carlos, 2002-08-22)
Dias, Joelmir Augusto Costa
;
Assaf, José Mansur
;
https://lattes.cnpq.br/9563312407691130
;
https://lattes.cnpq.br/8994385933947902
;
https://orcid.org/0009-0000-5458-7765
The effect of platinum addition in low contents (0.1 and 0.3 % wt.) in nickel supported γ−alumina catalyst (15% Ni wt.) has been investigated. The samples were prepared by successive wet impregnations of metal ions over alumina and calcined at 600oC. X-Ray diffraction analysis showed that, structurally, platinum did not make sensitive changes in the catalyst precursor. No changes have been observed in textural properties, as shown by B.E.T. and pore-volume experiments. However, temperature programmed reduction showed that platinum facilitates the reduction of nickel during the activation step. According to the temperature programmed hydrogen desorption analysis, a sensitive increasing in metallic area and a decrease in metallic particles size were observed. The promotion effect of platinum in steam reforming, partial oxidation and the oxidative reforming reactions was related with the metallic area increase or the metallic particle size decrease, increasing the methane conversion with the increase in the metallic area in the case of steam and oxidative reforming, and decreasing the specific activity with the decrease in the metallic particle size, in the case of partial oxidation. Diffuse reflectance of infrared spectroscopy analysis of reduced samples showed that, in these low contents, the platinum do not influences significantly the carbon monoxide adsorption over nickel. This is evidence that there are no sensitive electronic changes in nickel sites by these low platinum contents. The hydrogen production per methane consumed for oxidative reforming of methane is the largest of these three processes, making this process the most advantageous for hydrogen generation for fuel cells.
Uma arquitetura de segurança para ambientes de educação a distância
(Universidade Federal de São Carlos, 2002-08-27)
Castro, Reinaldo de Oliveira
;
Biajiz, Mauro
;
https://lattes.cnpq.br/8331600770992494
Distance Education (DE) is a very important theme that has been discussed intensively owing to the growing demand for continued education and to the modernization and availability of new technologies. Several DE environments have emerged as a result of the increasing popularity of the Internet, each offering a variety of resources, mainly to maximize the teaching/learning process. Due to its relevance to the DE theory, this process has been the focus of several researches aimed at developing this type of environment. As a result, designers and developers have devoted little attention to subjects not directly related to it. The purpose of this work, therefore, is precisely to broach on of these subjects, in the form of a safety architecture for DE environments that takes into account the aspects of authentication and control of user access. From the standpoint of authentication, the architecture employs the password and random question mechanisms coded using cryptographic keys. With regard to access control, the scheme formulated for the architecture combines a series of techniques that allow the manager of course in a DE environment the maximum flexibility and simplicity in managing the authorizations attributed to the users registered in the course. These techniques involve the use of collective/individual authorizations, positive/negative authorizations, and explicit/implicit authorizations.