Browsing by Issue Date, starting with "2003-12-17"

Filter results by year or month

Now showing 1 - 20 of 23134

Desenvolver a cidadania através da química : é possível? Um desafio a ser vencido
(Universidade Federal de São Carlos, 2003-12-17)
Azevedo, Leonardo Ribeiro de
;
Rodrigues, Rosa Maria Bonfá
;
https://lattes.cnpq.br/7795174030048711
The present work was inspired by the High School National Curriculum Parameters (PCNEM) as well the Schnetzler proposal of teaching chemistry to citizenship. It is also based on the observed chemistry teaching problems, inefficiency of teaching methodologies and governmental programs. Teaching chemistry under the viewpoint of maintainable social and environmental development offers opportunities to relate the work to the customary student daily life, the construction of concepts starting from facts, and of knowledge about information bound to the human being survival. The interpretation of these information was carried out using concepts already established and others concepts were built up to understand the subjects. This work applied a new methodological proposal (strategy) based on the constructive conceptions and the idea that chemistry should be taught to build up the basic abilities for citizenship, seeking to evaluate the teaching and learning process and also the method acceptance. The approach to the contents took in account the interdisciplinary, using Chemistry Science as a tool to interpret the facts in the real world. The results showed that the applied teaching methodology, according to PCNEM, was able to improve the student’s participation. The students started to act as managers of the learning process, being capable to supervise and elaborate their own ideas comparing them with the previously established scientific ideas. It was also observed that the scientific activity became something joyful and gratifying to the students.
A fábrica é escola. Práticas sociais e educativas de empresários e trabalhadores.
(Universidade Federal de São Carlos, 2003-12-17)
Gigante, Moacir
;
Silva, Petronilha Beatriz Gonçalves e
Education is usually treated from institutional, formal and schooling aspects. In this study however, education is investigated as a social work practice in the factory. The working day-to-day life of shoe factory workers in the city of Franca-SP is taken as the starting point. However, this is put in the context of relationships between historical capitalism and the historicity of the training in competencies for craftsmanship, manufacturing and industry, be it in general, in other manufacturing sectors, or be it in the specific context of the profession of shoemaker. Daily and oral history of workers are studied; the unique experience of each one of the collaborators in the research is the support base for the reflection and analysis on work and competencies training for work. Education for work is therefore studied: informal education, within the worker traditions, as well as institutional-scholarly education. Education as informal-professional, or institutionalscholarly is differently obtained and is differently destined for different functions and different social groups within the factory, a fact that accentuates and reinforces social stratifications. The creation of work competencies in the shoe factories is peculiarly associated, at each historical moment, with the very manner of organizing work routines. This fact implies a necessity for the comprehension of the real functions of formal education. This work contributes not only to the comprehension of the educational process and of the maintenance and extinction of the work competencies of footwear industry workers, but also to the comprehension of the aims of institutional education, in the past as well as in present society.
Geração de energia elétrica excedente no setor sucroalcooleiro: entraves estruturais e custos de transação
(Universidade Federal de São Carlos, 2003-12-18)
Souza, Zilmar José de
;
Azevedo, Paulo Furquim de
Given the estimated potential of electric energy generation around 18 thousand MW and the necessity to expand and diversify the installed national capacity of energy generation, this dissertation investigates the reasons for the low performance in the exploitation of the investment opportunities in electric energy commercialization by the sugarcane sector. With this purpose, the research presents a diagnosis of the main structural obstacles and transaction costs present in the generation of electric energy surpluses, showing the importance of the institutions in the decision of expansion of the activity by the sugarcane sector. The results were contrasted with the proposal of governmental energy policy for incentive this activity. It was verified the necessity of improvement in the current institutional environment. The main contribution of the dissertation was to present directives to public policies. These directives focus the financing for the expansion of the activity; the commercialization of the excesses; the tax incentive; and the concession of direct subsidies to the expansion of the activity. The directives related to financing were: official lines differentiated by technology use, index of mechanization and scale; the Ethical Fund Formation for the sector; and projects finance involving Emissions Reduction Certificate. Regarding commercialization, directives were: subvention to the transport tariffs; the extension of the universe of potentially free consumers; formation of trading pools and inclusion in the Energy Replacement Mechanism; the insertion of the sugarcane energy in the composition of Factor X and in the National Energy Reserve; changes in the retailers' auto-supplement; and incentive to the commercialization of energy surpluses and of Emissions Reduction Certificates. Directives related to tax incentive were also presented. Regarding direct subsidies, it is interesting the use of the resources that come from the Use of Public Good and Fuel Consume Account to foster the expansion of the energy surpluses commercialization.
Estimativa de variabilidade genética em acessos crioulos e cultivares comerciais de tomates (Lycopersicon esculentum Mill.) do sul do Brasil e avaliação da presença do Gene Mi
(Universidade Federal de São Carlos, 2003-12-18)
Carelli, Bernardete Primieri
;
Echeverrigaray, Sergio
;
https://lattes.cnpq.br/5630031784004533
;
Gerald, Lee Tseng Sheng
Cultivated tomato (Lycopersicon esculentum Mill.) is one of the most important horticultural crops. Although original from the Andes region, this crop was officially introduced in Brazil by the European immigrants during the last half of the XIX century. Today, old varieties and new improved cultivars are planted in the different Brazilian regions. In the last 20 years the Ecological Center of Ipê proceeded a rescue of old tomato varieties maintained by small agriculturists in the Northeast region of Rio Grande do Sul State. The present work had the objective to estimate the variability among 35 tomato accessions, 12 commercial cultivars and 23 Brazilian landraces using morphological descriptors and molecular traits (proteins and DNA), and to verify the Meloidogyne resistance/susceptibility status of these genotypes, as well as the presence of the Mi genes. The landraces were separate in five groups by their fruit characteristics: large oblate, cherry, heart-shape, large cylindrical, and rounded, whereas the commercial cultivars were restricted to the most common groups in the market. Both the quantitative evaluation of seed protein electrophoretic profiles, and RAPD markers allowed identifying all the accessions. The cluster analysis of RAPD data allowed to separate the genotypes in seven similarity groups that were not related with those formed by the protein analysis. Conversely, a discriminant analysis showed a relation between RAPD markers and fruit morphology. Landraces exhibited higher levels of protein and genetic (RAPD) variations compared with the commercial cultivars confirming the genetic variability reduction caused by the limited number of genotypes used in breeding programs. Experimental results showed that all the landraces and commercial cultivars, with the exception of the cultivars Polka Baixo and Gaucho (Feltrin) were susceptible to M. javanica, M. incognita, and M. arenaria. PCR data showed that the Mi1.2 gene was present only in the Polka Baixo cultivar, whereas the Mi1.1 was found in 26 accessions, most of which susceptible to root-knot nematodes, confirming the gene Mi1.2 as the nematode resistant determinant, and the inefficiency of the Mi1.1. Considering the high incidence of Meloidogyne in South Brazil, the low frequency of resistant accessions point-out the necessity of a special effort of breeding programs on the transfer of root-knot nematode resistance genes to Brazilian tomato varieties and cultivars.
A visão da escola sobre a interação com as famílias dos alunos: o cenário em primeiras séries do ensino fundamental
(Universidade Federal de São Carlos, 2003-12-18)
Cozer, Renata de Cassia
;
Reali, Aline Maria de Medeiros Rodrigues
The main objective of this qualitative research was to understand through observation some practices of the daily school and through interviews, the relationships established at the school, acted by the director, pedagogic coordinator and teachers of the first grades on elementary school, and the students' families there are enrolled in this series. The theoretical approached the historical context of the relationship between school and families and the problem of the teachers' graduation. Starting from the analysis of a group of representative situations of the interactions maintained between school and their students' families is ended that the professionals of the school - although they have opportunities to establish bonds with the students' families - they don't drive their actions for an effective approach. It is discussed as the public politics; the courses of initial formation and activities of continuous formation can focus the study of the underlying theories to the process established between school and families. The discussions of the educational practices can favor the critical reflection and the change of posture and of attitude on the part of the educators. It is believed that like this those professionals will get to recognize the families and the students for besides the differences of groups or classes, the contribution that these have to offer to the society. It is advocated that to rethink the dynamics and practices accomplished at the school, including the ones that involves the parents and the students' families, it favors classroom works returned for the students' success.
Gênero e educação: abordagens e concepções em dissertações de mestrado no estado de São Paulo
(Universidade Federal de São Carlos, 2003-12-18)
Jardim, Silvia Regina Marques
;
Abramowicz, Anete
The purpose s work is to analyze and systematize 19 (nineteen) dissertations that focused the educational process associated to gender category presented between 1990 to 2000, in universities located in Stated of São Paulo: Universidade Federal de São Carlos UFSCar; Universidade de Campinas UNICAMP; Universidade de São Paulo USP/SP and Pontifícia Universidade Católica - PUC/SP. Its intent is to examine how gender category has been conceptualized by educational studies, emphasizing main tendencies, difficulties and contributions presents in dissertations that articulate gender with education, in State of São Paulo. The results show there is little advancement in the junction between two areas. The works are fragmented and many themes need a profound study, mainly about the uses of gender category. In spite of some limits, gender s studies are relatively new in the Education field. However, this research observes the importance of junction between gender and educational studies because it permits to see different multiplicities. So, this fact makes to understand that there are important contributions in the articulation between gender and education. That s why the results demonstrate there is a progressive process in this junction between these two areas appointing to contributions, for example: fights against stereotypes of gender in schools; modification of a population (teachers, students); reflection about teaching work; discussions about gender discrimination in pedagogic discourses; movements into process of increasing people s understand of gender relationships; reflections about proximity between women and careers that presents low status social; emphasis in school Education as a social transformation instrument.
Propriedades funcionais e estruturais e concentração de fosfatos orgânicos em eritrócitos de dez espécies de morcegos pertencentes às famílias Phyllostomidae e Molossidae (Chiroptera - Mammalia)
(Universidade Federal de São Carlos, 2003-12-19)
Reinoso, Simoni Savazzi
;
Schwantes, Maria Luiza Barcellos
;
https://lattes.cnpq.br/3018620987507134
;
Schwantes, Arno Rudi
Hemoglobin structural and functional aspects, as well as the presence of intraerythrocitic organic phosphates of 167 individuals of 10 species of bats, belonging to Phyllostomidae (Artibeus planirostris, Phyllostomus discolor, Artibeus lituratus, Carollia perspicillata, Desmodus rotundus, Glossophaga soricina), and Molossidae family (Molossus ater, Molossus molossus, Nyctinomops laticaudatus e Eumops perotis) were studied. These individuals were collected in different areas of São Paulo State. Hemoglobin of these individuals were submitted to starch gel electrophoresis and showed all the same pattern: one slow major, migrating close to A2 human hemoglobin and one minor fast component, migrating close to human hemoglobin A. No intra and inter specific variation were detected. Variations on functional properties in blood were detected. Most of the species (7) presented normal Bohr effect, while C. perspicillata, D. rotundus e M. molossus null Bohr effect. Artibeus planirostris presented reverse Bohr effect. All the hemoglobin samples showed normal Bohr effect in the stripped form as well as in the presence of 2,3-biphospho glicerate and inositol hexaphosphate. The addition of this organic phosphate has altered both Bohr effect and P50 values. The oxygen affinities were high in all hemoglobins. In vivo, the oxygen affinity of bat hemoglobins is lower due to modulator effect,probably ,3.biphospho glicerate. In the erythrocytes of all individuals studied 2,3-biphospho glycerate were found in varying concentrations and a little higher than most of Mammals. No inositol polyphosphates were found in any sample tested.
Economias de escala em duas tecnologias alternativas: estudo do setor siderúrgico
(Universidade Federal de São Carlos, 2003-12-19)
Araújo, Juliano Bezerra de
;
Pinho, Marcelo Silva
An important characteristic of the capitalist industrial production is related to the exploration of the scale economies in a widespread way by firms with the purpose of enjoying better economical results. This was the case of the steel industry, which, in order to meet the increasing needs of operational efficiency started to adopt larger and larger equipment and facilities in their industrial plants. This path was more intense in the integrated plants, which present larger size than the mini-mills . This work investigates the role of the scale economies in the metallurgical processing, through extensive bibliographical research in specialized literature and visits to different companies. Besides, numerous interviews with metallurgists from several areas of these industries have been done. The results indicated, among other things, that most of the semi-integrated plants now in operation do not fully explore the potential of scale economies associated to the process, for having been constructed in sub-optimal scale. In a more dynamic demand scenery, a better exploration of this economy is expected, where it would prevail the path of increasing scales for both technological routes, the integrated and the semi-integrated plants.
Caracterização da gestão e de atividades de capacitação para o processo de desenvolvimento de produto alimentício: estudos de caso
(Universidade Federal de São Carlos, 2003-12-19)
Bosi, Mirela Guedes
;
Alliprandini, Dário Henrique
During the 90s, Brazilian market open to imported goods sets the beginning of food industry transformation in Brazil. Other factors led to competitiveness growth among food companies, such as: the development of new technology, and consumers knowledge and expectation level increase. Therefore, food companies were forced to seek for competitive advantage which allowed the differentiation of their products in the market. In this context, product development process (PDP) gains fundamental importance. Due to the importance of PDP in the food industry, this work seeks characterize the food product development process management. Besides, this work aims to characterize the capability to PDP. In order to reach these purposes, eight food companies and three organizations (ITAL, SENAI, and a consultant company) that backup food industry were studied. Three food companies were chosen out of the eight which were studied and were presented in this work. The chosen companies have a more structured PDP, which allows a discussion on capability building process. The findings showed that food companies follow a sequence of phases and activities during PDP. This sequence is very similar when food companies are compared with each other and with the theoretical background. Concerning capability, food companies see capability building restrict to courses, and to market fairs visiting. The organizations that backup food industry serve mainly small companies, which do not have either enough technical or managerial knowledge in order to develop a product. Therefore, we consider that food product development process management is based on technical aspects. However, a minimal of managerial structure has been started by the companies. Besides, the need to develop new products tends to make food companies put in resources to build capability.
Impacto da certificação florestal nas condições de trabalho no complexo florestal
(Universidade Federal de São Carlos, 2003-12-22)
Castral, Ana Paula
;
Alves, Francisco José da Costa
;
https://lattes.cnpq.br/9183120186518337
This assignment has as aim to analyze the impact of forest certification about the work conditions of forest workers. It s believed that, although the origin of forest certification had been conditioned by market factors, its social worries are producing effect at companies that adopted it. In this assignment will be described the formation of forest complex, reminding the fundamental policies for the consolidation of the current Brazilian complex. It ll also be done a short discussion of the two forest certification systems used in our country: FSC (Forest Stewardship Council) and CERFLOR (The Brazilian Forest Certification System). The assignment advances at the discussion of the forest production process and the organization of work at forest production. In this sense, the contribution of this assignment is to identify the changes at the work organization, occurred after the certification and if improvements at work conditions of forest workers had happened.
Regularidade global Gevrey das soluções de certas classes de operadores parciais lineares de primeira ordem
(Universidade Federal de São Carlos, 2004-01-01)
Coelho, Laurencie Salles
;
Petronilho, Gerson
;
https://lattes.cnpq.br/5917989984472668
In this work we study global Gevrey hypoellipticity on the Euclidean 2-space R² for a class of first order linear partial differential operators with coeffcients in Cw2χ (R). Necessary and suffcient conditions for global Gevrey hypoellipticity are proposed.
Expressão heterológa, purificação e caracterização estrutural do peptídeo (171-194) da p24 do HIV-1
(Universidade Federal de São Carlos, 2004-01-01)
Castilho, Priscila Vasques
;
Araújo, Ana Paula Ulian de
;
https://lattes.cnpq.br/5183458350445779
Proteins from the inner core of HIV-1 are involved in crucial processes during the virus life cycle. p24 is the major capsid protein of HIV and is initially expressed as part of the gag polyprotein. The association of gag proteins to the cell inner-membrane surface initiates virus assembly and induces budding from the host cell membrane. Thus, p24 plays an active structural role both as part of the Gag protein and in its mature form. In this sense, we have chosen a region from C-terminal of p24, TLRAEQASQEVKNWMTETLLVQNA, (p24-3) which is part of the major region responsible for protein dimerization. The linear peptide, rp24-3, and its cyclic variant, rp24-3m, were produced by recombinant strategy in Escherichia coli. The gene fragments were obtained by the synthetic gene approach and inserted into pET 32a to produce fusion proteins in the soluble form. The expression products were purified by Ni-affinity chromatography followed by an enzymatic cleavage. The peptides where purified by reverse phase chromatography and their primary sequence and molecular masses where inferred by amino acid sequence analysis and mass spectrometry, respectively. The rp24-3 secondary structure was investigated by circular dichroism and steady state fluorescence, been structured differently in water and in buffer. Besides, its tryptophan is in a partially buried environment and the addition of methanol above 70% caused a highly increase in helical content. In conclusion, this work shows a suitable system for rp24-3 production, providing satisfactory amount for structural studies.
Localização e orientação dos quimiorreceptores de CO2 e/ou pH envolvidos no controle dos reflexos cardio-respiratórios e da respiração aérea em jeju, Hoplerythrinus unitaeniatus (Teleostei, Erythrinidae)
(Universidade Federal de São Carlos, 2004-01-03)
Boijink, Cheila de Lima
;
Rantin, Francisco Tadeu
;
https://lattes.cnpq.br/3546242299713690
In the present study we determined the location and orientation of the CO2 and/or pH chemoreceptors and analyzed the cardio-respiratory responses and the aerial respiration in jeju (Hoplerythrinus unitaeniatus) during graded hypercarbia (1, 2.5, 5, 10 e 20% de CO2) and acid medium (pH ~ 7, 6.0, 5.8, 5.6, 5.3 e 4.7) (1, 2, 3, 4 e 5 mM de HCl). The chemoreceptors orientation was determined by means of a series of injections of different hypercarbic solutions (5, 10 e 20% de CO2) in the caudal vein (internal) and buccal cavity (external). To distinguish the orientation of the CO2 and H+ chemoreceptors, acid solutions (HCl) at same pH of the internal (pH 5.1, 4.9, and 3.7) and external (pH 5.6, 5.3, and 4.7) solutions were applied, and significant responses in relation to the control values were not recorded. In another group of fish previously tested acid solutions (30, 40, and 50 mM HCl) were injected. This injections caused a decrease in the extra-cellular blood pH to levels similar to those found during the injections of internal and external hypercarbic solutions. The location of the chemoreceptors was determined by bilateral denervation of branches of the cranial nerves IX (glossopharyngeal) and X (vagus) to the gills. The heart rate, arterial blood pressure, respiratory frequency and ventilation amplitude were recorded for intact and denervated fish. The data indicated that the CO2/pH chemoreceptors eliciting the cardio-respiratory responses to hypercarbia are exclusively branchial and are externally oriented. Jeju respond to hypercarbia of 5% CO2 with bradycardia, hypertension and increases in the ventilatory frequency and ventilation amplitude. Concentrations higher than 5% caused anesthetic effect. The cardiac responses are mediated by CO2/pH chemoreceptors distributed in all gill arches, while the respiratory responses are mediated by chemoreceptors located in the 1st gill arch. Furthermore, hypercarbia also induced aerial respiration in intact fish and in those with the 1st gill arch denervated. The denervation of the four gill arches did not abolish completely the aerial respiration, suggesting that chemoreceptors involved in this response are located in extra-branchial sites. The changes in the internal and external H+ concentrations or in the water did not affect the cardiorespiratory responses and aerial respiration frequency, unless if accompanied by hypercarbia.
Surdez e educação: pais de crianças surdas e ansiedade
(Universidade Federal de São Carlos, 2004-01-16)
Ferrini, Cyntia Maria Silva
;
Dias, Tárcia Regina da Silveira
;
https://lattes.cnpq.br/7222853843468945
A deaf child's birth brings the family into a new reality. Such reality might unchain anxiety states or not, depending on the conception the family has on deafness and deaf people as well as on interaction quality and established communication level. Facing that problem, this study aimed at getting to know the anxiety level of parents that attend orality services searching for oral interaction with their deaf children, and the anxiety level of those that attend bilingual services looking for interaction with their deaf children through the Brazilian Language of Signs (LIBRAS), homelike signs, speaking, and writing. In addition, this study has obtained and analyzed physiologic and behavioral measures of those parents that could be related to anxiety or not. For this, subjects took part in experiment sessions, where physiologic and behavioral reactions to stimuli were recorded and IDATE (Trace-Status Anxiety Inventory) was applied. The results of this study present difference among listener groups, orality and bilinguism as to the anxiety scale, with higher anxiety level among orality parents, while bilingual parents presented a higher anxiety than listener parents; however, this difference was not verified in physiologic measures, during the stimuli presentation. However, difference in those measures during experiment was found. On the other hand, behavioral categories indicated difference among groups. Having such results in mind, it would be interesting to confirm data from the anxiety scale with other scales, for instance, through application of Marilda Lipp s Stress test, the Analogical Scale of Humor, and Hamilton s scale for Anxiety.
Imigração e casamentos: o caso de São Carlos (1890 a 1939).
(Universidade Federal de São Carlos, 2004-01-19)
Conceição, Silvano da
;
Truzzi, Oswaldo Mário Serra
;
https://lattes.cnpq.br/5005536921435787
Avaliação do conceito bolha como critério de compensação ambiental em atividades poluidoras do ar atmosférico - estudo de caso no Estado de São Paulo
(Universidade Federal de São Carlos, 2004-01-22)
Santos, Elio Lopes dos
;
Salvador, Nemésio Neves Batista
;
https://lattes.cnpq.br/9930582531600560
The present study was an evaluation of the Bubble Concept a environmental criterium of compensation used by the United States Environmental Protection Agency and by the Environmental Agency of the CETESB in Cubatão, to regulate the implantation of new industrial enterprises and its amplifications. Studies ware done refering to the environmental licensing of the following industrial enterprise in the São Paulo State: Central of Energy Generatin of Santos lowland with the proposal of implantation in the area of the President Bernard s refinery in the Cubatão; Central of Energy Generation Carioba II, with the proposal of the implantation in the Americana town and a factory of Carbon Black, implanted in Paulínia. A bibliographic survey that included the scientific literature, that included national and international entities of research, Environmental Law of São Paulo State and Federal Environmental Law. In the stage of the interview technicians of the industries technicians of the Company of the Technology of Environmental Sanitation of São Paulo State were listened. Environmental Consultants, students of Pos-Graduation and Environmental Management of Santa Cecilia University, Justice Prosecutors and people of no governmental Organizations. It was concluded that the absence of criterium or even the use of criterium of environmental compensation with basis in the Bubble Concept founded in the exchange of pollutants in the proportion of 1:1 does not promote the improvement and the recovery of the quality of the air of the Regions and Sub-Regions saturated of atmospheric pollutants or in ways of saturation, contraposing itself to the Federal Law n. 6938. As an alternative to make the implantation of the new industrial enterprises or enlargements possible, with the improvement and recuperation of the air quality in Regions and Sub-Regions saturated of atmospheric pollutants this paper suggests several alterations in the Bubble Concept .
Estudos transcricionais em leucócitos de portador da síndrome de Down, através da técnica de análise serial da expressão gênica (SAGE)
(Universidade Federal de São Carlos, 2004-01-22)
Malagó Junior, Wilson
;
Silva, Flávio Henrique da
;
https://lattes.cnpq.br/1757309852446263
;
https://lattes.cnpq.br/2138911304735498
Efeitos da substituição da coleta em latões pela coleta a granel na estrutura de captação do leite
(Universidade Federal de São Carlos, 2004-01-23)
Fonseca, Ariângelo Geraldo Nunes da
;
Azevedo, Paulo Furquim de
The deregulation and trade liberalization in the begin of the 1990 s created the need of competitive strategies in the domestic dairy industry, notably in Mercosul. The new environment imposed a number of changes in this sector, as far as producers and industries are concerned. This dissertation aims to evaluate the result of one of these changes that were implemented in order to gain competitive advantage, by way of quality differentiation or cost savings in logistics. It is a case study about the bulk collection of refrigerated milk at Nestlé Brasil Ltda, which is a very representative firm of the dairy industry and where, until 1995, milk was collected in gallons. This process could be implemented with the introduction of cooling equipments in farms, in a partnership between the industry and producers, and also by the improvement of the industry vehicles used for milk transportation. These investments have produced a number of logistic changes that had a huge impact in the group of suppliers and the whole process of milk purchasing and collection. In this context, this dissertation offers an analysis, from the point of view of supply chain management, focusing on the chain efficiency, and of the New Institutional Economics, focusing on transaction costs.
Expressão heteróloga, purificação e caracterização das proteínas humanas DCRA (Down Syndrome Critical Region Gene A) e DSCR8 (Down Syndrome Critical Region Gene 8)
(Universidade Federal de São Carlos, 2004-01-27)
Corrêa, Elisete Márcia
;
Silva, Flávio Henrique da
;
https://lattes.cnpq.br/1757309852446263
Down syndrome is the most frequent cause of mental retardation affecting millions of people worldwide and results from full or partial trisomy of chromosome 21 (HC21). Rare cases of partial trisomy allowed the identification of a small region in HC21 common to all carriers called Down Syndrome Critical Region. The genes DCRA and DSCR8, mapped to this region, encode two proteins of unknown function. With the aim of contributing to a better characterization of these proteins, DSCR8 was subcloned and expressed in fusion with thiorredoxin in Escherichia coli Rosetta (DE3). Recombinant Trx-DSCR8, observed in the soluble fraction, was subjected to the initial purification assays by affinity chromatography in a Ni-NTA column. The gene DCRA was cloned and expressed in fusion with the proteins thiorredoxin and GFP allowing the partial purification of the protein and the achievement of crystallization and immunological assays. The amino acid sequence of DCRA showed 57% and 49% of identity to a protein of unknown function from Anopheles gambiae and Drosophila melanogaster respectively. Also, in silico analyses revealed that DCRA contains a putative Vps26 domain. Subcellular localization of DCRA in fusion with GFP was observed preferentially in the cytoplasm of the cell lines tested. These results contribute to a better characterization of DCRA and DSCR8 and open up possibilities towards the understanding of the cellular role of these proteins and their relationship with the Down syndrome.
Síntese, caracterização e estudos cinéticos da isomerização de compostos de Ru(II) contendo ligantes (X-bipy) ( X=-H, -NO2, -Me, - COOH, -SMe, O=SMe, -Cl, -OMe)
(Universidade Federal de São Carlos, 2004-01-30)
Santiago, Marcelo Oliveira
;
Batista, Alzir Azevedo
;
https://lattes.cnpq.br/6469642481998660
The synthesis of coordination compounds containing bipyridine derivative ligands and the influence of the substituent groups on the physical and chemical properties were studied in this work. Mixed compounds of the type [RuCl2(P P)(X bipy)] were synthesized, where X - bipy represents the bipyridine derivatives and P - P = triphenylphosphine (PPh3)2, 1,4-bis(diphenilphosphino)butane (dppb). The characterization of the compounds showed that the isomer formed in solution is dependent on the phosphine used. The isomer of the compounds containing the triphenylphosphine exhibited a structure where the phosphine groups are mutually in trans position. For the biphosphine compounds, dppb is trans to N-heterocyclic ligand. The spectroscopic and electrochemical properties of the compounds showed dependence with substituent group of the bipyridine. It was observed a linear correlation of the pKa values of the X-bipy ligands with the redox potential of the complexes. The decrease of the pKa value with the increase in the electronwithdrawing ability of the X groups makes the ligand less basic. This effect enhances the π-backbonding interactions, which implies in the energy decrease of the MLCT transitions and in the redox potential increase of the metal center. For the [RuCl2(dppb)(X-bipy)] complexes, the isomerization reactions under light incidence were monitored by electronic spectroscopy or differential pulse voltammetry. The photolysis study of the compound with the 2,2'-bipyridine ligand allowed the assignment of the field ligand state for its photochemical activity. The kinetic data supplied the assignment of a twist mechanism for the isomerization process. It was observed an increase in the rate constant value for this process with the increase pka values of the ligand. The reactivity of the compound [RuCl2(COD)]n, COD is 1,5- cyclooctadiene ligand, with the substituted bipyridine was studied in order to obtain compounds containing different compositions with changes in reaction conditions. Compounds of the type [RuCl2(COD)(X-bipy)], for X = H and Me, were obtained and characterized by microanalysis, hydrogen nuclear magnetic resonance (RMN) and electrochemical techniques. The reactions with other bipyiridines resulted in mixtures of compounds of hard purification, needing a more systematic studies for the correct attribution of their composition and structures. Tris(diimine)ruthenium complexes, [Ru(X-bipy)3](PF6)2 with X = H, Me, MeO, MeS, were obtained and characterized by microanalysis, hydrogen nuclear magnetic resonance and electrochemical techniques. With substituent groups containing sulfur atom, MeS and MeSO, polinuclear complexes were obtained. The [RuCl2(P-P)(MeS-bipy)][(µ)-RuCl2(P-P)], [RuCl2(CO)(PPh3)2]2[(µ) RuCl2(dppb)(MeS-bipy)] and {[RuCl2(dppb)]3[(µ)-Ru(MeSObipy) 3]}(PF6)2 compounds were synthesized and characterized by spectroscopic and electrochemical techniques. An interesting electronic conducting mechanism was observed. The sulfur atom is believed to withdraw electron density of the metallic center by backdonation interaction transferring to the pyridine ring which, by being more basic, transfer part of this density to the second metallic center.