Two distinct mechanisms underlie progesterone-induced proliferation in the mammary gland.

The mouse mammary gland develops postnatally under the control of female reproductive hormones. Estrogens and progesterone trigger morphogenesis by poorly understood mechanisms acting on a subset of mammary epithelial cells (MECs) that express their cognate receptors, estrogen receptor alpha (ERalpha) and progesterone receptor (PR). Here, we show that in the adult female, progesterone drives proliferation of MECs in two waves. The first, small wave, encompasses PR(+) cells and requires cyclin D1, the second, large wave, comprises mostly PR(-) cells and relies on the tumor necrosis factor (TNF) family member, receptor activator of NF-kappaB-ligand (RANKL). RANKL elicits proliferation by a paracrine mechanism. Ablation of RANKL in the mammary epithelium blocks progesterone-induced morphogenesis, and ectopic expression of RANKL in MECs completely rescues the PR(-/-) phenotype. Systemic administration of RANKL triggers proliferation in the absence of PR signaling, and injection of a RANK signaling inhibitor interferes with progesterone-induced proliferation. Thus, progesterone elicits proliferation by a cell-intrinsic and a, more important, paracrine mechanism.

Are there transformative indicators for motivation to learn?

Fourteen nursing s tudents enrolled in a community coll ege were chosen by purposeful se lection to be i nterviewed in a qualitative survey. A proposed mode l of Learner Motivation Development was examined . The mode l describes four stages of motivati on development progression across the lifespan: I Survival (infancy to childhood), I I Expl oration (childhood to adolescence), III Identification (pre- adulthood), and IV Reflection ( adulthood ). This r esearch examined the last two stages. The criteria used to categorize the students within the fr amework were bas ed on human development theories as described by Maslow (1954) and Erikson (1950). The concept of critica l thinking proposed by Brookfield (1987) and the ideas of transformative learning expressed by Mezirow (1991) were also incorporated. The researcher' s criteria , antici pated behaviours and characteri stics, were used to ana lyze the students' responses to open-ended questions. The central theme of the research was based on the assumption that motivation to learn is intrinsic and inherent in pre-adult and adult learners. Six pre-adults and two adults met the descriptors set for stage III Identification. Five adults and one pre-adult met the criteria for stage IV Reflection. The impact of life e xperiences and maturation were clearly demonstrated.

New Building Blocks for Dual-Property Molecule-Based Magnets

Two classes of compounds have been prepared and characterized as building blocks for chiral magnets and ferromagnetic conductors. In the fIrst project, the organic framework of a pentadentate, (N302) macro cycle has been synthetically modifIed to introduce phenyl substituents into its organic framework and the synthesis of four new [Fe(In(N302)(CN)2] complexes (I) - (IV) is presented. [Molecular diagram availble in pdf] This work represents the fIrst structural and magnetic studies of a family of spin crossover macrocycles that comprise of both structural and stereo-isomers. Magnetic susceptibility and Mossbauer data for the R,R-complex (I) is consistent with both a thermal and a light induced spin crossover transition. The X-ray data supports a change in geometry accompanying the thermal spin transition, from a high spin (HS) 7 -coordinate complex at room temperature to a low spin (LS) 5-coordinate complex at 100 K. The crystal structure ofthe racemic complex (III) reveals a HS, 7-coordinate complex at 200 K that undergoes no signifIcant structural changes on cooling. In contrast, the magnetic - susceptibility and Mossbauer data collected on a powder sample of the racemic complex are consistent with a LS complex. Finally, the meso complex (IV) was prepared and its structure and magnetic properties are consistent with a 5-coordinate LS complex that remains low spin, but undergoes conformational changes on cooling in solution. The chiral [Fe(H)(N302)(CN)2] macro cycle (I), together with its Mn(H) and Fe(H) derivatives have also been exploited as building blocks for the self-assembly of chiral magnets. In the second project, a synthetic route for the preparation of tetrathiafulvalene (TTF) donors covalently attached to a diisopropyl verdazyl radical via a cross conjugated pyridyl linker IS presented. Following this strategy, four new TTF-py- (diisopropyl)verdazyl radicals have been prepared and characterized (V) - (VIII) . [Molecular diagram available in pdf] The first (2:1) charge transfer complex ofa TTF-py-(diisopropyl)verdazyl radical donor and a TCNQ acceptor has been prepared and structurally characterized. The crystal packing shows that the donor and acceptor molecules are organized in a mixed stacking arrangement consistent with its insulating behaviour. EPR and magnetic susceptibility data support intramolecular ferromagnetic interactions between the TTF and the verdazyl radicals and antiferromagnetic interactions between TTF donors within a stack. In an attempt to increase the intramolecular exchange interaction between the two radicals, a TTF-x-(diisopropyl)verdazyl radical (IX) was prepared, where the two radicals are connected ia a conjugated divinylene linker. The neutral radical donors stack in a more favourable head-to-head arrangement but the bulky isopropyl groups prevent the donor radicals from stacking close enough together to facilitate good orbital overlap. [Molecular diagram available in pdf].

Caractérisation de la dynamique des berges de deux tributaires contrastés du Saint-Laurent : le cas des rivières Batiscan et Saint-François

L’érosion des berges est un processus clé de la dynamique fluviale. Elle influence considérablement la charge sédimentaire des rivières et contrôle l’évolution latérale des chenaux. Les méthodes de caractérisation des mécanismes et des variables affectant l’érosion des berges sont toutefois imprécises et difficiles à appliquer. Ce projet a pour objectif de caractériser la dynamique actuelle des berges de deux tributaires contrastés du Saint-Laurent : les rivières Saint-François et Batiscan. Le premier objectif vise à quantifier les caractéristiques géotechniques de deux tronçons des rivières à l’étude près de l’embouchure avec le Saint-Laurent en décrivant la stratigraphie à différents sites typiques et en recueillant des échantillons de sédiments afin de mesurer différentes variables géotechniques (granulométrie, limites d’Atterberg, résistance à l’érosion mécanique, résistance à l’érosion fluviale). Le second objectif vise à quantifier les principales caractéristiques hydrodynamiques (précipitations, débits, cisaillements, vitesses) des deux sections de rivière. Le troisième et dernier objectif cherche à mesurer les taux d’érosion à l’échelle saisonnière en utilisant des relevés GPS et des chaînes d’érosion et à identifier les mécanismes d’érosion qui opèrent sur les rivières. Les résultats montrent une érosion importante des berges sur chacun des tributaires, mais les mécanismes qui la cause diffèrent. La Batiscan possède des berges dont le matériel est cohésif et ses berges sont principalement marquées par des ruptures de masse. La Saint-François présente des berges peu cohésives ce qui favorise l’érosion fluviale. Le taux de recul sur la rivière Saint-François est de l’ordre de 1 à 3 m/an dans certaines sections de la rivière. Une nouvelle méthode de mesure du cisaillement critique d’érosion fluviale à l’aide d’un chenal expérimental a été élaborée. Les cisaillements critiques obtenus se situent entre 1,19 et 13,41 Pa. Les résultats montrent que les facteurs jouant sur l’érosion des berges ont une variabilité intrinsèque et systémique difficile à mesurer. Le protocole expérimental développé dans ce projet s’est toutefois avéré utile pour étudier les principales variables qui influencent l’érosion des berges, tout en quantifiant les taux d’érosion et les mécanismes d’érosion de berge de deux tributaires importants du fleuve Saint-Laurent. Ce protocole pourrait être utile dans d’autres contextes.

Ordered mesoporous silica as supports for immobilization of biocatalyst

Mesoporous materials are of great interest to the materials community because of their potential applications for catalysis,separation of large molecules,medical implants,semiconductors,magnetoelectric devices.The thesis entitled 'Ordered Mesoporous Silica as supports for immobilization of Biocatalyst' presents how the pore size can be tuned without the loss in ordered structure for the entrapment of an industially important biocatalyst-amylase.Immobilization of enzymes on ordered mesoporous material has triggered new ooportunities for stabilizing enzymes with improved intrinsic and operational stabilities.

De Generalista a Especialista : Motivações para a formação especializada em enfermagem : o caso das organizações de saúde públicas, na sub-região oeste do distrito de Lisboa

O presente estudo, enquadrado na área de gestão de recursos humanos, tem como principal objectivo identificar os factores motivacionais que orientam a adesão à especialização, no grupo profissional dos enfermeiros. Trata-se de um estudo de natureza exploratória, transversal, descritivo, analítico, comparativo e quantitativo. A população do estudo foi o grupo de enfermeiros portugueses, sendo a sua amostra composta por 150 enfermeiros. Este grupo foi seleccionado a partir de um processo de amostragem probabilística estratificada, sem reposição. O instrumento de recolha de dados foi o inquérito por questionário. Para o efeito usou-se o questionário da motivação para a formação (QMF) de Carré (2001), tendo sido já adaptado para a população portuguesa por Correia (2009). A formação contínua é uma condição importante no desenvolvimento do indivíduo, quer a nível pessoal, quer a nível profissional; assim como no desempenho da organização onde o indivíduo exerce a sua profissão. O presente trabalho pretende, assim, identificar os factores motivacionais na função de enfermeiro, e que conduzem à adesão da especialização, em particular ao Curso de Pós-Licenciatura em Enfermagem. Numa primeira parte, faz-se a definição e avaliação da função, desenhando-se um mapa de competências; identificando-se, em paralelo, os motivos/expectativas que levam estes profissionais da saúde à especialização desta mesma escala. Decorrente dos resultados obtidos, o presente trabalho conclui que as duas principais motivações dos enfermeiros para a frequência do CPLEE são a motivação extrínseca Operacional Pessoal e a motivação extrínseca Operacional Profissional. Foi ainda possível determinar que a idade, o género, o vínculo à instituição e a situação financeira também têm um papel decisivo no que concerne à motivação dos enfermeiros para a frequência do CPLEE. Este estudo permitiu ainda consolidar o questionário da motivação para a formação desenvolvido por Philippe Carré, aplicado à população portuguesa, de forma a analisar a motivação dos enfermeiros portugueses para a frequência do CPLEE. Quanto às implicações práticas, pretende-se contribuir para o desenvolvimento e melhoria das práticas de recursos humanos no sector da saúde. Balança-se aqui, consequentemente, um equilíbrio entre o diagnóstico organizacional, e a prescrição prática. Potencialmente, poderá servir de roadmap para áreas como o recrutamento e selecção, gestão de carreiras, formação e desenvolvimento, desenho de trabalho e de funções; e, adicionalmente, para uma melhor gestão académica do ensino pós-graduado, na carreira da enfermagem.

Risky attitudes towards road use in pre-drivers

Motor vehicle accidents are one of the principal causes of adolescent disability or mortality and male drivers are more likely to be involved in road accidents than female drivers. In part such associations between driver age and sex have been linked to differences in risky behaviour (e.g. speed, violations) and individual characteristics (e.g. sensation seeking, deviant behaviour). The aim of this research is to determine whether associations between risky road user behaviour and individual characteristics are a function of driver behaviour or whether they are intrinsic and measurable in individuals too young to drive. Five hundred and sixty-seven pre-driver students aged 11-16 from three secondary schools completed questionnaires measuring enthusiasm for speed, sensation seeking, deviant behaviour and attitudes towards driver violations. Boys reported more risky attitudes than girls for all measures. Associations between sensation seeking, deviant behaviour and attitudes towards risky road use were present from early adolescence and were strongest around age 14, before individuals learn to drive. Risky attitudes towards road use are associated with individual characteristics and are observed in adolescents long before they learn to drive. Safe attitudes towards road use and driver behaviour should be promoted from childhood in order to be effective. (C) 2007 Elsevier Ltd. All rights reserved.

Motivation in second language acquisition in Chinese research students in the UK

The present study sets out to examine motivation to learn English by Chinese research students in an informal setting. Data were collected, using semi-structured interviews, from four research students at two points in time during their first year in the UK. The main findings are: they believed that learning English was important; their main goal orientations were instrumental and extrinsic; they set learning goals and persisted to attain them; they valued their current learning environment in general and saw it as supportive of their goals; they held both positive and negative attitudes towards the British, which had differential effects on their motivation; their self-perceived support seemed to have a positive impact on their motivation and the development of self-confidence; they tended to attribute their success to stable causes such as the environment and failure to unstable but controllable causes such as effort. It is concluded that qualitative data of this kind may complement insights from quantitative research. Implications for target country institutions in the provision of support are discussed.

Estudo da moagem de alta energia e sinterização de pós compósitos W-Cu

The Tungsten/copper composites are commonly used for electrical and thermal objectives like heat sinks and lectrical conductors, propitiating an excellent thermal and electrical conductivity. These properties are dependents of the composition, crystallite size and production process. The high energy milling of the powder of W-Cu produces an dispersion high and homogenization levels with crystallite size of W very small in the ductile Cu phase. This work discusses the effect of the HEM in preparation of the W-25Cu composite powders. Three techniques of powder preparation were utilized: milling the dry with powder of thick Cu, milling the dry with powder of fine Cu and milling the wet with powder of thick Cu. The form, size and composition of the particles of the powders milled were observed by scanning electron microscopy (SEM). The X-ray diffraction (XRD) was used to analyse the phases, lattice parameters, size and microstrain of the crystallite. The analyse of the crystalline structure of the W-25Cu powders milled made by Rietveld Method suggests the partial solid solubility of the constituent elements of the Cu in lattice of the W. This analyse shows too that the HEM produces the reduction high on the crystallite size and the increase in the lattice strain of both phases, this is more intense in the phase W

Influência na qualidade final de metais retificados através da variação da velocidade de mergulho

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Acupuntura: histórico, bases teóricas e sua aplicação em Medicina Veterinária

A acupuntura (AP) é uma técnica terapêutica empírica desenvolvida em uma cultura oriental e que utiliza pensamento mágico (linguagem pré-científica) em seu raciocínio. É uma terapia reflexa que utiliza a estimulação de pontos específicos do corpo com objetivo de atingir um efeito terapêutico ou homeostático. A AP preconiza que a saúde é dependente das funções psico-neuro-endócrinas, sob influência do código genético e de fatores extrínsecos como nutrição, hábitos de vida, clima, qualidade do ambiente, entre outros. O presente artigo faz uma breve revisão sobre a filosofia da AP, seus marcos históricos na China e no Ocidente, a história da AP veterinária no Brasil e no mundo. Também aborda a prática da AP, incluindo as formas de diagnóstico, a definição do protocolo de tratamento, os métodos de estimulação dos pontos, o agulhamento de animais, suas indicações, contra-indicações e reações adversas.

Transient current effects on poly(o-methoxyaniline) films irradiated by pulsed electron beam

Fast transient current decay was recorded on POMA samples during current pulses (in the order of milliseconds) provided by a low energy electron beam under an applied field. The characteristic time decay depends on the electron beam energy and on the bias polarity. The results were explained taking into account the effect of space charge, the intrinsic conductivity of the non-irradiated region of the sample and the radiation-induced conductivity of the thin irradiated region. Fitting parameters may provide the value of both intrinsic and radiation-induced conductivities and the average electron range.

Efeitos a longo-prazo do tratamento neonatal com glutamato-monossódico no dimorfismo sexual esquelético e secreção de leptina e corticosterona

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Espaço e focalização em The ambassadors, de Henry James

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Discriminante de corpos de números

Pós-graduação em Matemática - IBILCE