La plupart des composés organiques ont un atome de carbone tétravalent, où tous les électrons de valence sont utilisés pour former des liaisons covalentes. En parallèle, la chimie des composés divalents ayant un carbone(II) s’est développée après l’isolement de carbènes stables par Bertrand en 1985. Auparavant, en 1961, Ramirez a rapporté l’isolement de l’hexaphénylcarbodiphosphorane, que l’on peut considérer comme un composé présentant un carbone(0) avec ses deux doublets libres, lui permettant de coordiner jusqu’à deux acides de Lewis. A partir de 2006, les propriétés électroniques de ces ligands ont été étudiées au travers d’études théoriques par Frenking ; ce qui a permis à Bertrand et Fürstner d’isoler et d’ajouter des nouveaux membres à cette famille. Cette classe de ligand est aujourd’hui connue sous le nom de “carbônes”, avec comme formule générale CL2 (L = PR3 ou carbène).Cette famille n’a jamais été utilisée dans le domaine de la catalyse. C’est pourquoi nous avons, décidé d’etudier les propriétés électroniques de ce ces composés au travers de la catalyse à l’or, afin de les comparer aux NHC, phosphines, et phosphites. Récemment, nous avons utilisé ces composés pour générer des complexes donneur accepteur avec du GaCl3, et de corréler leurs différentes caractéristiques géometriques à leurs propriétés électroniques en utilisant les règles de Gutmann sur des adduits acide/base de Lewis. De plus, nous avons isolé des “dimères” ioniques dont la formation peut être expliquée par les propriétés intrinsèques des ligands. Nous avons ainsi démontré par ces deux approches que les “carbônes” sont de meilleurs donneurs que les NHC. / Most organic compounds which are stable in the condensed phase contain tetravalent carbon atoms, where all four valence electrons are being engaged in chemical bonds. On the other hand, the chemistry of divalent carbon(II) was only recognized after the isolation of a stable persistent carbene by Bertrand and co-workers in 1985. Such products display one s-type lone pair orbital and are thus good ligands. Earlier on, concern was also paid to a new family of compounds, first reported in 1961 by Ramirez and co-workers. They can be considered as divalent carbon(0) derivatives with two lone pairs at the central carbon, with a possibility of double coordination of two Lewis acids to this carbon. This feature was proposed by Kaska in 1973, and verified later by the isolation of di-metalated adducts. From 2006, these compounds were the centre of extensive theoretical investigations by Frenking, which led to the isolation of new members of this family by Fürstner and Bertrand. This family is now referred to as “carbones”, of general formula CL2 (L =PR3 or carbene).“Carbones” are still virtually unused in catalysis. Thus, we have decided to study these derivatives, especially in the field of gold catalysis, and to compare them with well-known ligands such as NHCs, phosphines and phosphites. Recently, we were able to synthesize their corresponding GaCl3 complexes and to rationalize their electronic properties through Gutmann’s rules for Lewis acid/Lewis base adducts. In addition, we obtained some ionic “dimers” and we explained their formation on the basis of ligand’s electronic properties. We have shown through these two approaches that carbones are far better donors than NHCs.

O fator de indução de proteólise (proteolysis-inducing factor) ou PIF é uma glicoproteína de 24 kDa encontrada no plasma de pacientes com câncer e responsável pelo catabolismo de proteínas musculares associado a caquexia neoplásica. O presente trabalho investigou pelas técnicas de RT-PCR, RACE-PCR e Real-time PCR a presença de formas de expressão de mensagens do PIF em vários tipos celulares derivados de tecido normal e tumoral. A expressão de mRNA do gene foi testada em 37 amostras de tumores e 4 tecidos normais, sendo detectada em 7 de 20 linhagens tumorais de mama, uma linhagem tumoral de cólon e no tecido normal da mama, placenta e testículo. A expressão significativa do gene PIF entre as linhagens metastáticas da mama foi confirmada pela técnica de Real-time PCR. Uma nova variante da mensagem (PIF-SV), contendo um novo éxon de 64 bp, inserido entre os éxons 4 e 5, foi identificada em tecido normal de mama pela técnica de RACE-PCR. Esta forma variante de PIF é expressa concomitante com a forma principal de PIF em tumores primários da mama, linhagens tumorais de mama e nos tecidos normais da mama e placenta. Parece que o PIF exerce funções fisiológicas nos tecidos normais. / Proteolysis-inducing factor (PIF) is a 24 kDa glycoprotein identified in plasma of cancer patients and responsible for muscle catabolism associated with the process of cancer cachexia. The present study has investigated, using the RT-PCR, RACE-PCR and Real-time PCR techniques, the presence of PIF messages in different cell types derived from normal and tumor tissues. The PIF mRNA expression was examined in 37 tumor and 4 normal tissue samples and detected in 7 of 20 breast tumor cell lines, one colon tumor cell line and in normal breast, placenta and testis tissues. The differential expression of PIF message in metastatic breast cell lines was confirmed by the Real-time PCR technique. A new splicing form of the message, containing one new exon of 64bp, inserted between the exons 4 and 5, was identified in normal breast tissue. This splicing form of PIF is expressed concomitantly with a main form of PIF in breast tumor cell lines and also in normal breast and placenta tissue. These data suggest that PIF exhibits physiological functions in normal tissues. An over-expression and a production of a new splicing form (PIF-SV), seem to contribute in some event leading normal cell to a malignant phenotype.

Made available in DSpace on 2014-06-12T17:36:12Z (GMT). No. of bitstreams: 2 arquivo2555_1.pdf: 2355246 bytes, checksum: 67878edb28caadb5dda261416c723874 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Do total de energia consumida no país, aproximadamente 43% é consumida pelo setor industrial e do total da energia elétrica consumida na indústria, cerca de 60% destinase aos motores elétricos. Depois da energia elétrica, o ar comprimido é a forma de energia mais consumida na indústria. É também a forma de energia mais onerosa e, também a mais negligenciada. A falta de um projeto adequado e de uma manutenção regular faz com que os sistemas de ar comprimido, muitas vezes, representem uma fonte de desperdício de energia elétrica. Este trabalho descreve a aplicação da modelagem, controle e inteligência artificial para melhorar a eficiência energética em sistemas industriais. Apresenta ainda oportunidades de melhoria da eficiência do sistema, mostrando a influência da pressão de trabalho no consumo de energia, bem como o desperdício devido a vazamentos. A implementação do sistema de controle aplicada em sistemas de ar comprimido é apresentada com os dados experimentais obtidos no Laboratório de Otimização de Sistemas Motrizes da Universidade Federal de Pernambuco. Comparações quanto ao consumo de energia são realizados usando as estratégias de controle convencionais e a proposta neste trabalho

Les nucléolipides sont des molécules amphiphiles dont la structure bio-inspirée dérive de celle des acides nucléiques. Leur auto-assemblage en milieu aqueux aboutit à la formation d’objets supramoléculaires de morphologies et structures très diverses. La morphologie a été caractérisée par des techniques complémentaires de microscopie optique et de diffusion de la lumière, tandis que leur structure a été déterminée par la diffusion des rayons X. Il a ainsi été mis en évidence l’existence et le rôle fondamental des interactions faibles entre têtes polaires, au sein des auto-assemblages. La nature de ces interactions faibles a été déterminée par des techniques de spectroscopies IR et UV. Un premier objectif a été de mettre en évidence l’importance de ces interactions, ainsi que leur corrélation avec d’autres facteurs qui régissent le mécanisme d’auto-assemblage, tels que la nature chimique des amphiphiles, ou la morphologie et la structure des objets supramoléculaires en présence.Par ailleurs, la tête polaire nucléotide permet également d’imaginer la formation d’interactions faibles entre les auto-assemblages et un monobrin d’acide nucléique, à l’image des interactions spécifiques entre bases azotées présentes dans l’ADN. Lors de ce travail, nous nous sommes intéressés à une méthode de vectorisation d’acides nucléiques par des objets eux aussi chargés négativement. Contrairement aux approches classiques, l’interaction électrostatique est ici défavorable et l’association repose alors uniquement sur des interactions faibles spécifiques, estimées en spectroscopie. De façon surprenante, la formation des complexes a pu être mise en évidence par des expériences de diffraction des rayons X et un modèle approprié a permis de proposer des mécanismes de formation des complexes. Les propriétés thermodynamiques des différents complexes formés ont été évaluées par la technique de Calorimétrie à Titration Isotherme (ITC). Un point remarquable a été la mise en évidence systématique de trois types de comportements sur l’ensemble des complexes étudiés en fonction de la nature et de la spécificité des interactions mises en jeu. Ceci nous a ainsi permis de proposer différents mécanismes de formation pour chaque type de complexe observé. / Nucleolipids are amphiphilic molecules which bio-inspired structure derives from nucleic acid structure. Their self-assembling behaviour in aqueous medium leads to the formation of supramolecular objects of very different morphologies and structures. The morphology has been characterized with optical microscopy and light scattering complementary techniques, whereas their structure has been determined with X-ray scattering. Thus the existence and the fondamental role of weak interactions between polar heads inside the self-assemblies have been highlighted. The nature of these weak interactions has been determined with IR and UV spectroscopies techniques. A first objectif has been to highlight the importance of these interactions, as well as the their correlation with other factors which drive the mechanism of self-assembly, such as the chemical nature of amphiphiles or the morphology and structure of the supramolecular objects.Moreover the nucleotide polar hear also allows to imagine the formation of weak interactions between the self-assemblies and a single-stranded nucleic acid, such as those highlighted in DNA. In this work, we found interest in a nucleic acid vectorisation method with negatively charged objects as well. On the contrary of classic approaches, electrostatic interaction was here defavorable and assembling relies only on specific weak interactions, estimated with spectroscopy methods. Surprisingly, complexes formation could be highlighted with X-ray scattering experiments, and an appropriate model has allowed the proposal of mechanisms for the formation of complexes. Thermodynamic properties of the different complexes formed have been evaluated with Isothermal Titration Calorimetry (ITC) technique. A remarkable point was the systematic highlighting of three types of behaviour on the whole set of complexes studied, depending of the nature and the specificity of the weak interactions implied. This led us to different proposals for the mechanism of formation of each type of complex studied.

O presente estudo integra informações bioestratigráficas e paleoecológicas obtidas através da análise de foraminíferos planctônicos e bentônicos recuperados dos sedimentos provenientes de cinco poços (1-MAS-1, 1-MAS-3A, 1-MAS-4A, 1-MAS-14 e 1-MAS-15) da Bacia de Barreirinhas, perfazendo um total de 127 amostras de calha preparadas e analisadas. Os sedimentos aqui analisados abrangem os andares Albiano superior ao Campaniano superior com registro geológico inserido nos grupos Caju (Albiano - Cenomaniano) e Humberto de Campos (Turoniano - Maastrichtiano). Através dos dados bioestratigráficos obtidos foi possível estabelecer sete biozonas de foraminíferos, de caráter local, com base na última ocorrência do táxon guia (LAD - Last Appereance Datum). O Albiano superior foi definido com base nas biozonas do foraminífero planctônico Ticinella primula Lauterbacher (1963) e foraminíferos bentônicos Lingulogavelinella albiensis Malapris (1965)-Gyroidina bandyi Trujillo (1960); o Cenomaniano inferior foi determinado através das biozonas do foraminífero planctônico Globigerinelloides bentonensis Morrow (1934) e foraminífero bentônico Coronorotalites aptiensis Bettenstaedt (1952); o Cenomaniano superior foi reconhecido através das biozonas do foraminífero planctônico Rotalipora appeninica Renz (1936) e foraminífero bentônico Gavelinella intermedia Berthelin (1880); o Campaniano superior foi determinado com base na biozona do foraminífero planctônico Heterohelix pulchra Brotzen (1936). Após a identificação da microfauna, foi possível reconhecer 108 espécies de foraminíferos pertencentes a cinco subordens: a Subordem Globigerinina, de foraminíferos planctônicos, é representada por 40 espécies e 15 gêneros; os foraminíferos bentônicos são compostos por 68 espécies e 48 gêneros, pertencentes as Subordens Rotaliina, Textulariina, Lagenina e Miliolina. Através da análise da assembléia de foraminíferos, foi possível traçar a CCD (Carbonate Compensation Depth - Profundidade de Compensação do Carbonato) nos poços e separá-los com base na profundidade em: distais (1-MAS-1 e 1-MAS-14) e proximais (1-MAS-3A, 1-MAS-4A e 1-MAS-15). Observou-se que a Bacia de Barreirinhas possui uma tendência geral transgressiva ao longo do Período Cretáceo, caracterizada por meio do influxo sedimentar através de variações climáticas, como o aquecimento global ocorrido neste período. Esta teoria é reforçada pela completa ausência de tecas calcárias, tanto de foraminíferos bentônicos, quanto planctônicos, associada à ocorrência exclusiva de bentônicos aglutinantes e silicosos (Reophax globosus) nos poços distais ao final do Período Cretáceo. Nos poços 1-MAS-3A, 1-MAS-4A e 1-MAS-15, a fauna de foraminíferos identificada apresenta adaptações morfológicas a condições de baixa oxigenação na coluna d'água, características normalmente observadas durante os Eventos Oceânicos Anóxicos (Oceanic Anoxic Event - OEA). Como exemplo destas adaptações morfológicas, foram identificadas três espécies pertencentes ao gênero Schakoina, que possui câmaras alongadas e a espécie Biticinella breggiensis, que possui câmaras bilobadas, sugerindo um aumento na produtividade primária, disponibilidade de nutrientes e paleoambientes depletados em oxigênio. Com base nestas informações foi possível identificar que um Evento Anóxico de caráter local tenha ocorrido durante o Albiano superior, registrado somente nos poços 1-MAS-3A e 1-MAS-4A, enquanto que o Evento Anóxico Global 2 foi registrado no poço 1-MAS-15. / This study integrates biostratigraphic and paleoecological information obtained through of planktonic and benthic foraminifera analysis from sediment recovered from five wells (1-MAS-1, 1-MAS-3A, 1-MAS-4A, 1-MAS-14 and 1-MAS-15) of Barreirinhas Basin, making a total of 127 samples prepared and analyzed. The sediments analyzed here cover the upper Albian to upper Campanian stages with geological record inserted in the Caju (Albian - Cenomanian) and Humberto de Campos (Turonian - Maastrichtian) groups. Through the biostratigraphic data obtained it was possible to establish seven foraminiferal biozones, of local character, based on the last occurrence of taxon guide (LAD - Last Appereance Datum). The upper Albian was defined based on planktonic foraminifera biozones of Ticinella primula Lauterbacher (1963) and benthic foraminifera Lingulogavelinella albiensis Malapris (1965)-Gyroidina Bandy Trujillo (1960); the lower Cenomanian was determined through the planktonic foraminifera biozones of Globigerinelloides bentonensis Morrow (1934) and benthic foraminifera Coronorotalites aptiensis Bettenstaedt (1952); the upper Cenomanian was recognized through the planktonic foraminifera biozones of Rotalipora appeninica Renz (1936) and benthic foraminifera Gavelinella intermedia Berthelin (1880); the upper Campanian was determined based on the planktonic foraminifera biozone Heterohelix pulchra Brotzen (1936). After the identification of microfauna, was possible to recognize 108 species of foraminifera belonging to five suborders: the Suborder Globigerinina, of planktonic foraminifera, is represented by 40 species and 15 genera; the benthic foraminifera are composed of 68 species and 48 genera, belonging to the suborders Rotaliina, Textulariina, Lagenina and Miliolina. Through analysis of foraminifera assemblage it was possible to trace the CCD (Carbonate Compensation Depth) in the wells and separate them based on depth in: distal (1-MAS-1 and 1-MAS-14) and proximal (1-MAS-3A, 1-MAS-4A and 1-MAS-15). It was noted that the Barreirinhas Basin has an overall transgression during the Cretaceous Period, characterized by sedimentary influx through weather changes, like global warming that occurred during this period. This theory is enhanced by the complete absence of calcareous tests, both of benthic as planktonic foraminifera associated with the exclusive occurrence of agglutinating and arenaceous benthic (Reophax globosus) in the distal wells of the end of Cretaceous Period. In the wells 1-MAS-3A, 1-MAS-4A and 1-MAS-15, the foraminifera fauna identified presents morphological adaptations to conditions of low oxygen in the water column, features typically seen during the Oceanic Anoxic Event (OEA's). As examples of these morphological adaptations, was identified three species of the Schakoina genera, which has elongated chambers and Biticinella breggiensis species, which has bilobeted chambers, suggesting an increase in the primary productivity, nutrient availability and paleoenvironments depleted in oxygen. Based on this information it was possible to identify a local character anoxic events occurred during the upper Albian, recorded only in a well 1-MAS-3A and 1-MAS-4A, while the global anoxic event 2 was recorded in a well 1-MAS-15.

Submitted by Edisangela Bastos (edisangela@ufpa.br) on 2017-03-14T13:48:58Z No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V1.pdf: 57161941 bytes, checksum: 64c7c852b8b12d6b6fb94e5bb4f764e5 (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V2.pdf: 32769288 bytes, checksum: 7af66526e4b238adbe988fd4851281f2 (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-03-17T12:05:28Z (GMT) No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V1.pdf: 57161941 bytes, checksum: 64c7c852b8b12d6b6fb94e5bb4f764e5 (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V2.pdf: 32769288 bytes, checksum: 7af66526e4b238adbe988fd4851281f2 (MD5) / Made available in DSpace on 2017-03-17T12:05:28Z (GMT). No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V1.pdf: 57161941 bytes, checksum: 64c7c852b8b12d6b6fb94e5bb4f764e5 (MD5) Tese_MetodologiaInterpretacaoRadargeologica_V2.pdf: 32769288 bytes, checksum: 7af66526e4b238adbe988fd4851281f2 (MD5) Previous issue date: 1995-09-29 / Desenvolve-se nesta tese o Método Sistemática de Elementos Radargráficos, inédito em termos mundiais, na interpretação geológica em imagens de Radar de Visada Lateral (Radargeologia), uma técnica de grande relevância no campo dos recursos naturais, tendo em vista ser a década de 90, a década do Radar. O Método Sistemática de Elementos Radargráficos (SER) revela de forma sistemática o roteiro metodológico adotado, quer através do texto, quer através de Figuras esquemáticas ou em imagens Radar de Visada Lateral (RVL), os elementos radargráficos (feições), auferidos em cinco diferentes estádios (etapas): Leitura, Reconhecimento, Identificação, Análise e Interpretação (stricto sensu). O Estádio Leitura visa lêr o significado dos elementos de imagem no terreno, objetivando entender seu significado; o Reconhecimento procura agrupá-los de acordo com a textura e tom radargráficos, a fim de obter zonas radargráficas homogéneas; o Identificação visa o estudo das formas de relevo em tais zonas, no que concerne a topo e pendente, como tambem o estudo dos padrões de drenagem, grau de dissecação e resistência à erosão; e o Análise estabelece as relações espacial e temporal das formas de relevo pesquisadas, através das feições lineares, planares e tabulares. De posse de tais informações, atinge-se o Estádio Interpretação, propriamente dito, no qual é possível a definição de litologias, estruturas circulares, descontinuidades, dobras e suas inter-relações, objetivando a execução do Mapa Radargeológico. Com efeito, selecionou-se uma área modelo para servir de paradigma aos diferentes estádios metodológicos acima reportados. Como um exemplo da aplicação do "Método Sistemática de Elementos Radargráficos", utilizou-se a região abrangida pela Sinéclise do Parnaíba e seu embasamento, com uma área em torno de 925 000 km2 , envolvendo principalmente os estados do Maranhão e Piauí, dispostos na região nordeste ocidental do território brasileiro. Tal exemplo visa enfatizar a aplicabilidade do sensoriamento remoto em terrenos sedimentares e seu embasamento metamórfico, haja vista a importância acadêmica e econômica que a mesma se reveste. Para a realização desta etapa utilizaram-se 52 mosaicos de imagem de Radar de Visada Lateral, escala 1:250 000, GEMS, banda X, resultando na definição de 39 unidades radargeológicas principais, com posicionamento temporal relativo, e 19 estruturas regionais e 30 locais, em que mais da metade são inéditas. Tais resultados estão expressos em texto explicativo e ilustrações, dentre os quais um Mapa Radargeológico na escala ao milionésimo, e um esboço estrutural na escala 1:2 000 000. Conclui-se pela potencialidades das imagens de Radar de Visada Lateral em mapeamentos geológicos, cujas dificuldades na definição dos elementos radargráficos (feições), devido principalmente a extensas sombras, encurtamento de pendentes, "layover" e efeitos paralaxe serão superados em Sistemas de Radar mais sofisticados (modo digital, estereoscopia, multifreqüência, diferentes ângulos de incidência, etc), a exemplo do SIR-C e RADARSAT . Finalmente, atestou-se a excelência do Método Sistemática de Elementos Radargráficos, em vista dos resultados alcançados no estudo da Sinéclise do Parnaíba e de seu embasamento, como seja: definição de unidades radargeológicas, as quais guardam estreita relação com as unidades litoestratigráficas já descritas na literatura; arcabouço estrutural com identificação de quase meia centena de morfoestruturas de caráter regional e local, em sua maioria inéditas; e perfeita correlação com mapas aeromagnéticos. / This thesis develops the Radargraphic Elements Sistematic method, unknown throughout the world, in the geologic interpretation with Side-Looking Radar (Radargeology), a technique of major relevante in the field of natural resources, considering that the 1990s are the Radar's decade. The Radargraphic Elements Sistematic (SER) method reveals in a sistematic form the methodological route adopted , be it trough the text, trough schematic figures, or in Side-Looking Radar (SLR), with the radargraphic elements (features), ordered in five different stages: Reading, Recognizing, Identifying, Analisys and Interpretation (stricto senso). The stage Reading seeks to understand the meaning of the image elements in the terrain, with the goal of understand their meaning ; the Recognizing stages seek to group them according to the texture and tone radargraphic, so as to obtain homogeneous radargraphic zones; Identification seeks to study the relief forms in such zones, with regard to top and pending, as well as the studying of the drainage patterns, dissection degree and erosion resistance ;and the Analysis establishes the spacial and temporal relation of the relief forms researched through linear, planar and tabular features. With such information in hand , the Interpretation stage itself is reach, in which is possible to define lithologies, rounded structures, unconformities, discontinuities, folds and their interrelations,with a view to executing the Radargeological Map.In effect, a model area was selected to serve a paradigm for the the different methodological stages. To apply the Radargraphic Elements Sistematic method, the region encompassed by Parnaíba Sineclyse and its embasement was selected, with an area of around 925 000 km2, involving mostly Maranhão e Piauí states, located in northeastern region of Brazil. Such an example seeks to emphasys the applicability of the remote sensing in sedimentar terrains and their metamorphic embasement, due to academic and economic importance involved.. To carry out this stage, 52 SLR images mosaics were utilized, scale, I: 250 000, GEMS, X band, resulting in the definition of 39 basic radargeologicals unities, with a temporal stratigraphy, and 19 regional strucutures and 30 local ones, of which more than half were unpublished. These results are expressed in an explanatory text with ilustrations, including a Radargological Map on the milionth scale , and a structural sketch on the scale of 1:2 000 000. The study reaches a favorable conclusion regarding the potentialities of SLR images in geological whose difficulties in defining the radargraphic elements (features) due mainly to extensive shadows, foreshortening , layover and paralaxe effects, will be overcome with the use of more sophisticated Radar Systems (digital mode, stereoscopy, multifrequency, differents angles of incidence,etc) , as is the case with SIR-C and RADARSAT. Finally, the study attests of the excelence of Radargraphic Elements Sistematic method considering the results achieve with the study of the Parnaíba Sineclyse and its embasement, such as : definition of radargeological units, which mantain a strict relation with the lithostratigraphic units already described in the literature; structural setting with the identification of almost 50 morphostructures of regional and local character , and a perfect correlation with aeromagnetic maps.

The main aim of this study was to explore whether or not low achievers in EFL at a Japanese university perceive peer cooperation in cooperative learning contexts to be effective in improving their levels of expectancy, motivation and ultimate attainment in the L2. The main findings in this study pertain to the relationship between peer cooperation and L2 classroom motivation. The relationship involved several perceived routes which mainly indicated that the learners felt that peer cooperation had had a positive influence on their levels of motivation. The perceived routes linking peer cooperation to motivation can be roughly divided into two types; 1) the two routes which were mainly focused on in this study: through expectancy alone or a combination of levels of English and expectancy; and 2) other routes identified during the course of the study: through group cohesion and/or cohesion-generated factors (a sense of responsibility for their peers and having fun in class) or through factors related to status ordering or hierarchy among students (feelings of superiority/inferiority to their peers).

La programación de un PLC se podría considerar un arte digital por donde se puede identificar lo bueno y malo, es decir lo bueno podría considerarse con la obtención de un producto terminado en forma correcta y malo cuando se presentan fallas a la hora de un proceso a plena producción, y justo para este último caso está la programación de PLC que se trata de identificar los errores de un proceso para evitarlos totalmente y así obtener como final un producto a satisfacción del cliente. El micro procesador LOGO está diseñado para realizar el rol de controlador automatizado de varios procesos tantos como su memoria por ejemplo tenemos disponibles en un LOGO 24 entradas digitales, 20 salidas digitales, 8 entradas analógicas, 8 salidas analógicas, convirtiéndolo en un PLC completo capaz de controlar con eficiencia.

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Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is a low-abundance signaling lipid important for the maintenance of the endomembrane system and selected membrane trafficking pathways. In yeast, in response to hyperosmotic stress, PI(3,5)P2 levels rise more than 20-fold in 5 minutes, and return to near basal levels in 30 minutes. This transient change suggests that PI(3,5)P2 levels are tightly regulated and may be involved in signaling a response to stress. In yeast, PI(3,5)P2 is synthesized through phosphorylation of PI(3)P by the PI(3)P 5-kinase Fab1. Loss of PI(3,5)P2 in yeast causes swollen vacuoles, defective retrograde trafficking from the vacuole, defective vacuole acidification, and mis-localization of a subset of vacuole lumenal proteins. In yeast, Vac14 is a regulator of PI(3,5)P2 levels. Mammalian Vac14 and Fab1 are found in the same complex. To study the physiological significance of PI(3,5)P2, a mouse strain was generated with the Vac14 gene disrupted by a gene-trap genomic insertion. Vac14 protein was not detectable in mutant mice. In fibroblasts cultured from the mutant mice, PI(3,5)P2 and PI(5)P are decreased to 42% and 44% of the corresponding wild-type levels, respectively. The mutant mouse brains exhibit spongiform-like morphology. Cytoplasmic vacuoles are found in neuronal cell bodies of the olfactory bulb, trigeminal ganglion, and dorsal root ganglion. Non-neural tissues appear largely normal. Similar vacuoles are also found in cultured neurons and fibroblasts. In fibroblasts, these vacuoles are formed from swelling of late endosomes/lysosomes. Some early endosomes are also enlarged. A population of cation-independent mannose-6-phosphate receptor (CI-M6PR), which recycles between endosomes and the trans-Golgi network (TGN), is trapped in early and late endosomes, indicating a block in endosome-to-TGN trafficking. These results suggest that: 1) Neurons are acutely sensitive to loss of PI(3,5)P2. 2) In mammals, PI(3,5)P2 is required for the morphology of late endosomes/lysosomes and retrograde trafficking from endosomes to the TGN. The first conclusion is supported by another mouse strain with a retro-transposon inserted in the Fig4 gene. Fig4 is another regulator of PI(3,5)P2 levels. Similar neurodegeneration was observed in the Fig4 mutant mice.