Strategies to cope with negative social identity: Predictions by social identity theory and relative deprivation theory

Predictions by social identity theory (SIT) and relative deprivation theory (RDT) concerning preferences for strategies to cope with a negative in-group status position were tested. The focus of the present research was a comparison of the theories regarding their differential patterns of prediction. For this purpose, a natural sample within a specific historical situation was investigated: East Germans after the German unification. First, the predictive power of SIT and RDT variables was tested separately. In a second step, a possible integration of the theories was addressed. Combining the SIT variables and RDT variables led to an integrated model indicating a differential pattern of prediction for intergroup strategies. The RDT components explained the collective responses, whereas SIT constructs were related to individual strategies. People prefer a positive self-evaluation that is based on their own judgments as well as those of others (Taylor & Brown, 1988). They try to differentiate themselves positively from others. One important source of self-evaluation is the relative status position of the groups people belong to and identify with. Depending on the outcome of a comparison with relevant out-groups, this statu

A novel approach for the efficient modeling of material dissolution in electrochemical machining

This work presents a novel approach to efficiently model anodic dissolution in electrochemical machining. Earlier modeling approaches employ a strict space discretization of the anodic surface that is associated with a remeshing procedure at every time step. Besides that, the presented model is formulated by means of effective material parameters. Thereby, it allows to use a constant mesh for the entire simulation and, thus, decreases the computational costs. Based on Faraday's law of electrolysis, an effective dissolution level is introduced, which describes the ratio of a dissolved volume and its corresponding reference volume. This inner variable allows the modeling of the complex dissolution process without the necessity of computationally expensive remeshing by controlling the effective material parameters. Additionally, full coupling of the thermoelectric problem is considered and its linearization and numerical implementation are presented. The model shows good agreement with analytical and experimental validation examples by yielding realistic results. Furthermore, simulations of a pulsed electrochemical machining process yield a process signature of the surface roughness related to the specific accumulated electric charge. The numerical examples confirm the simulation's computational efficiency and accurate modeling qualities

Patterns of Tumor Progression Predict Small and Tissue-Specific Tumor-Originating Niches

The development of cancer is a multistep process in which cells increase in malignancy through progressive alterations. Such altered cells compete with wild-type cells and have to establish within a tissue in order to induce tumor formation. The range of this competition and the tumor-originating cell type which acquires the first alteration is unknown for most human tissues, mainly because the involved processes are hardly observable, aggravating an understanding of early tumor development. On the tissue scale, one observes different progression types, namely with and without detectable benign precursor stages. Human epidemiological data on the ratios of the two progression types exhibit large differences between cancers. The idea of this study is to utilize data of the ratios of progression types in human cancers to estimate the homeostatic range of competition in human tissues. This homeostatic competition range can be interpreted as necessary numbers of altered cells to induce tumor formation on the tissue scale. For this purpose, we develop a cell-based stochastic model which is calibrated with newly-interpreted human epidemiological data. We find that the number of tumor cells which inevitably leads to later tumor formation is surprisingly small compared to the overall tumor and largely depends on the human tissue type. This result points toward the existence of a tissue-specific tumor-originating niche in which the fate of tumor development is decided early and long before a tumor becomes detectable. Moreover, our results suggest that the fixation of tumor cells in the tumor-originating niche triggers new processes which accelerate tumor growth after normal tissue homeostasis is voided. Our estimate for the human colon agrees well with the size of the stem cell niche in colonic crypts. For other tissues, our results might aid to identify the tumor-originating cell type. For instance, data on primary and secondary glioblastoma suggest that the tumors originate from a cell type competing in a range of 300 – 1,900 cells

Extended Distal Pancreatectomy with En Bloc Resection of the Celiac Axis for Locally Advanced Pancreatic Cancer: A Case Report and Review of the Literature

Due to a lack of early symptoms, pancreatic cancers of the body and tail are discovered mostly at advanced stages. These locally advanced cancers often involve the celiac axis or the common hepatic artery and are therefore declared unresectable. The extended distal pancreatectomy with en bloc resection of the celiac artery may offer a chance of complete resection. We present the case of a 48-year-old female with pancreatic body cancer invading the celiac axis. The patient underwent laparoscopy to exclude hepatic and peritoneal metastasis. Subsequently, a selective embolization of the common hepatic artery was performed to enlarge arterial flow to the hepatobiliary system and the stomach via the pancreatoduodenal arcades from the superior mesenteric artery. Fifteen days after embolization, the extended distal pancreatectomy with splenectomy and en bloc resection of the celiac axis was carried out. The postoperative course was uneventful, and complete tumor resection was achieved. This case report and a review of the literature show the feasibility and safety of the extended distal pancreatectomy with en bloc resection of the celiac axis. A preoperative embolization of the celiac axis may avoid ischemia-related complications of the stomach or the liver

Predicting the spatial distribution of stoats, ship rats and weasels in a beech forest setting using GIS

Using trap data the Hawdon, Poulter and South Branch valleys, a spatial distribution model was created for Stoats (Mustela erminea), Ship Rats (Rattus rattus) and Weasels (Mustela nivalis) in the North Branch of the Hurunui River. Ten spatial attributes were analysed in this thesis as potential spatial predictors of Stoats, Ship rats or Weasels; four of which were distance related measurements (distance from ecotonal edge, distance from river, distance from river tributary and distance from trapping edge); three were climate based variables (mean maximum temperature, mean minimum temperature and mean precipitation) and three were topographical based variables (elevation, aspect and slope). Relationships that existed between each spatial attribute and the number of Stoats, Ship Rats and Weasels caught were quantified by comparing the significance of the mean trapping rate with each spatial attribute and expressed spatially as maps in a Geographical Information System (GIS). Results from this thesis found elevation, aspect and distance from ecotonal edge as potential spatial predictors of Stoat populations. Elevation and aspect were found to be potential predictors of Ship rat and Weasel populations. GIS is able to predict the spatial distribution of pest species to a similar (or better) level compared to more formal associative models. The potential of GIS is however, restrained by the same limitations associated with these models. By using a larger trapping data set and identifying a number of social interactions between Stoats, Ship Rats and Weasels, one can improve the accuracy of spatially modelling each species within a Beech forest environment. Therefore, improve our understanding how landscapes influence the distribution of each pest species

Observation of EDM plasma behavior influenced by parasitic working gap capacitance

Machining large surfaces to good surface qualities is currently difficult, as optimisation of parameters does not always lead to a satisfactory outcome. This appears to be an issue with traditional EDM, and the cause is not understood very well. Observing this effect by looking at current and voltage is very difficult because of the parasitic capacitance. As the capacitance is a function of surface area and gap width, small gaps, as they occur when using small energies, result in a large capacitance. The charge of the capacitance can have the same order of magnitude as the discharge itself. This makes it hard to understand what actually happens in the gap while measuring current and voltage on the outside. In order to understand this phenomenon large, optically transparent SiC electrodes were used to observe the gap with a high speed camera. By doing so it is possible to locate consecutive discharges and to determine if the capacitance has a large effect on the behaviour of the plasma. The goal of this work is to identify the effect that is responsible for the difficulties with the machining of large high-quality surfaces in order to work out possibilities to enable those machining operations

Dispersal within a spatially structured population of lesser kestrels: The role of spatial isolation and conspecific attraction

1. Factors governing dispersal rates have seldom been examined in spatially structured populations of vertebrates. We gathered information during 8 years on transfer rates between subpopulations in a spatially structured, growing population of colonial lesser kestrels Falco naumanni, and analysed the contribution of several variables related to spatial isolation and characteristics of both subpopulation of origin and destination on probabilities of dispersal. 2. Lesser kestrels were highly philopatric to their subpopulations, but first-breeders dispersed more often than adults (26% vs. 4%, n = 1706) because adults were reluctant to move from familiar areas. Frequency of subpopulation change was higher in females than in males (first-recruiters: 30% vs. 22%, n = 987; adults 5% vs. 1%, n = 719), according to their different breeding roles. However, all populational factors had an equal effect on individuals of different sex and dispersal status. 3. Movement rates decreased with inter-subpopulation distance - indicating that travelling to distant subpopulations may impose costs in terms of breeding prospects -and with the number of subpopulations, which increased during our study period. 4. Conspecific attraction strongly influenced the probability of dispersal: it was relatively higher in largely populated subpopulations, and individuals of large subpopulations were reluctant to change to others. These results were neither influenced by the size and breeding density of the subpopulations nor by habitat quality in terms of food availability or risk of predation, as indicated by breeding success of kestrels at each subpopulation. The number of conspecifics could be used by the kestrels as a cue of patch quality in terms of settlement options, and large subpopulations could be more easily detected by prospecting birds. 5. Our study highlights the fact that several assumptions of theoretical metapopulation modelling are often not fulfilled in nature. Both theoretical models and management strategies on spatially structured populations or metapopulations should thus consider the number, population size, and spatial distribution of local populations, as well as their relationships with the dispersal ability of the species.Peer Reviewe

Estabilização proteica de vinhos: avaliação de alternativas para minimizar a aplicação de bentonite

As características sensoriais de um vinho, assim como a sua estabilidade, são fatores determinantes para a aceitabilidade do vinho no mercado, face à exigência dos consumidores atuais. A desnaturação das proteínas do vinho é responsável pelo aparecimento de turvação nos vinhos brancos. Esta instabilidade proteica pode ser causada por fatores intrínsecos ou extrínsecos, como peso molecular e ponto isoelétrico das frações proteicas no vinho, força iónica, grau alcoólico e pH do vinho ou condições de armazenamento. Para prevenir a instabilidade proteica são usados vários produtos enológicos com objetivo de remover as proteínas instáveis, evitando assim a sua desnaturação/precipitação. O agente de colagem mais usado para adsorção das proteínas do vinho é a bentonite sódica. Esta possui carga elétrica negativa, com capacidade de interagir eletroestaticamente com as proteínas do vinho de carga maioritariamente positiva, conduzindo à sua floculação e consequente precipitação. Apesar da colagem com bentonite ser o método mais utilizado, apresenta algumas limitações, particularmente quando aplicada em doses elevadas. Isto sucede, porque a bentonite para além de remover proteínas pode também interagir com outros compostos, nomeadamente com os que contribuem positivamente nas características sensoriais, tais como os compostos voláteis. Assim, um dos objetivos do presente trabalho foi avaliar a aplicação de aditivos enológicos que permitam estabilizar as proteínas do vinho branco, em alternativa à bentonite. Numa fase preliminar, foram testados diferentes produtos nomeadamente bentonite, taninos enológicos, carboximetilcelusose (CMC), enzimas, gel de sílica, quitosana e manoproteínas em diferentes doses, com o intuito de avaliar o seu efeito na estabilização proteica do vinho branco. A bentonite e as manoproteínas foram os que apresentaram melhores resultados de estabilidade proteica. Considerando os resultados obtidos, foram selecionadas cinco bentonites e onze manoproteínas comerciais, para ensaios de estabilização das proteínas dum vinho branco. Foi avaliada a influência destes produtos enológicos na composição fenólica, capacidade de acastanhamento, características cromáticas e sensoriais do vinho branco. Os resultados obtidos confirmaram a eficiência da bentonite na estabilização proteica dos vinhos. Por outro lado, algumas manoproteínas estudadas também mostraram uma influência positiva na estabilização proteica do vinho. Inserido no presente estudo foi ainda efetuada uma caracterização das manoproteínas quanto à sua composição em açúcares (quantitativo e qualitativo) e o conteúdo em proteína. Com base na caracterização efetuada às manoproteínas foi possível estabelecer uma ligação entre a percentagem de manose e a sua eficiência na estabilização proteica do vinho, dependendo esta da percentagem de manose. A bentonite não influenciou a composição fenólica, mas algumas manoproteínas diminuíram os compostos fenólicos totais. Relativamente às características cromáticas as manoproteínas de um modo geral conduziram a um aumento da luminosidade (L*) e a um aumento da coordenada da cromaticidade (b*), contudo apenas um dos vinhos tratados apresentou uma variação de cor detetável pelo olho humano. Na análise sensorial, não foram detetadas diferenças significativas nos vinhos analisados, porém, após a análise de componentes principais, foi possível descriminar os vinhos em três grupos, sendo o grupo mais pontuado aquele que continha apenas vinhos tratados com manoproteínas. Estes resultados estão de acordo com a caracterização dos açúcares efetuada às manoproteínas, sugerindo que a elevada pontuação atribuída a este grupo, se encontra relacionada com a elevada percentagem em glucose. Este trabalho pode fornecer informações importantes, conducentes a alternativas eficientes na estabilização proteica de vinhos brancos e que simultaneamente incrementa as características sensoriais do vinho. The sensory characteristics of a wine, as well the stability, are determinant factors for acceptability of wine in the market, face of current consumer exigency. White wine proteins denaturation is responsible for the appearance of haze in white wine. This protein instability may be caused by intrinsic or extrinsic factors, such as molecular weight and isoelectric point of wine protein fraction, ionic strength, pH and alcohol content of wine or storage conditions. To prevent protein instability, several oenological products are used, with the aimed to remove instable proteins, preventing their denaturation/precipitation. Sodium bentonite is the most commonly fining agent used to adsorption of wine proteins. This compound has a negative electrical charge, with capacity to interact electrostatically with wine proteins charged mostly positively, leading to flocculation and consequently precipitation. Although fining with bentonite being the most commonly used method, present some limitations, particularly when applied in high doses. This occurs, because addition of bentonite remove proteins and may interact with other compounds, namely with compounds that contribute positively in sensorial characteristics, such as volatile compounds. Thus, the propose of this work was to evaluate the application of oenological additives, that enable stabilize white wine proteins, as an alternative to bentonite. In a preliminary trial, were tested different types of products, namely bentonite, oenological tannins, carboxylmethylcellulose (CMC) enzymes, silica gel, chitosan and mannoproteins with different dosage, in order to evaluate their effect in white wine proteins stabilization. Bentonite and mannoproteins presented the best results. Based on these results we select five bentonites and eleven commercial mannoproteins. In this trials, it was evaluated the influence of this oenological products in phenolic composition, browning potential, chromatic and sensory characteristics of a white wine. The results obtained confirm the efficiency of bentonite in wine protein stabilization. Moreover, some mannoproteins studied also showed a positive influence in wine protein stabilization. Inserted into this study, it was also performed a mannoprotein characterization on sugars composition (quantitative and qualitative) and protein content. Based on mannoprotein characterization, it was possible to establish a relation between percentage of mannose and its efficiency in wine protein stabilization, depending on mannose percentage. Bentonite did not influence phenolic composition, but some mannoproteins decreased the total phenolic compounds. Regarding chromatic characteristics mannoproteins generally lead to an increase in lightness (L*) and an increase in yellowness (b*), however just one treated wine showed a variation in colour detected by human eye. In sensory analyses, no significant differences were detected among the analyzed wines, however, after principal components analyses; it was possible to discriminate wines into three groups, being the high scored group, which contains just wine treated with mannoproteins. This results are in accordance with sugars characterization performed at mannoproteins, which may suggest that high score attributed at this group is related with high percentage of glucose. This work may provide important information, leading to efficient alternatives in white wine proteins stabilization, and simultaneously, increase sensory characteristics

Prática de ensino supervisionada em educação pré-escolar e ensino do 1.º ciclo do ensino básico

O presente relatório final de estágio foi desenvolvido no âmbito da Prática de Ensino Supervisionada do curso de Mestrado em Educação Pré-escolar e do 1º Ciclo do Ensino Básico e pretende descrever, refletir e fundamentar algumas das intervenções pedagógicas desenvolvidas em contexto Pré-escolar e 1º Ciclo do Ensino Básico, decorridas numa Instituição Particular de Solidariedade Social e numa escola de rede pública, respetivamente. No decorrer da ação educativa tentamos apoiar a iniciativa e motivação das crianças, para que elas fossem co construtoras de saberes, assumindo-nos como observadores, apoiantes e estimuladores das suas ações. Da observação emergiu a tomada de decisões ao nível de novas propostas educacionais, uma vez que procuramos conciliar as áreas de conteúdo e curriculares com os interesses e necessidades do grupo de crianças. Relativamente à organização, este relatório encontra-se dividido em três grandes capítulos, sendo o primeiro relativo à contextualização das instituições onde foram desenvolvidas as intervenções pedagógicas bem como do grupo de crianças; o segundo capítulo abarca um conjunto de reflexões e análises referentes à organização do espaço, do tempo, das interações bem como as experiências de aprendizagem desenvolvidas em ambos os contextos. Por último, no terceiro capítulo é realizada uma reflexão global acerca das construções por nós efetuadas enquanto futuros educadores/professores. Destaca-se a importância desta etapa formativa na construção de competências cognitivas e relacionais para o desenvolvimento pessoal e profissional, do futuro educador/professor. This final report stage was developed under the Supervised Teaching Practice of the Master of early childhood and primary school education and aims to describe, reflect and support some of the pedagogical interventions developed in the context early childhood education and primary school, elapsed in a private Institution of Social Solidarity and a public school, respectively.During the educational tried to support the initiative and motivation of children, that they were co construction of knowledge, taking us as observers, supporters and promoters of their actions. Observation emerged the decision making level of educational proposals, since they seek to reconcile the curricular content areas and with the interests and needs of the group of children.For the organization, this report is divided into three main chapters, the first on the context of the institutions where they were developed educational interventions as well as the group of children, the second chapter comprises a collection of reflections and analyzes concerning the organization of space, time, interactions and learning experiences developed in both contexts.Finally, the third chapter is held a comprehensive discussion about the constructions made by us as future educators / teachers. We emphasize the importance of this formative stage in the construction of cognitive and relational skills for personal and professional development, the future educator / teacher