973 resultados para Reenkola, Elina M.: The veiled female core


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In social Hymenoptera, the division of labour is a major step in the evolution of sociality. Bees, which express many different kinds of sociality, can be classified according to how individuals share or do not share foraging and reproductive activities (Michener, 1974). The large carpenter bee, Xylocopa virginica, lives in populations with both solitary and social nests. In social nests, reproduction is controlled by the dominant female, who does all of her own foraging and egg-laying, while the subordinates guard the nest only. This study examined foraging behaviour as a way to classify the social hierarchy. Individual females were marked, measured and intensely observed for the foraging season. It was found that a large number of subordinates forage and likely obtain more reproductive fitness than previously thought. The dominance hierarchy is very likely a social queue, in which bees take turns foraging and egg-laying.

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Abstract This descriptive study sought to identify the similarities and differences between the various educational institutions offering therapeutic recreation curriculum across Canada. The study utilized mixed methods, including open and closed-ended questions on a survey and document analysis. The research participants were from 14 educational institutions located across the nation. Results from this study identify similarities and differences in the curriculum used to prepare students pursuing a career in the TR field. Core competencies and standards of practice for the field of therapeutic recreation were defined and discussed. Accreditation and the accrediting bodies in the field of TR are reviewed because of their significant impact on curriculum. Implications regarding certification and regulation pertaining to the education for therapeutic recreation practitioners were discussed along with suggestions for future research.

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Diatoms are renowned for their robust ability to perform NPQ (Non-Photochemical Quenching of chlorophyll fluorescence) as a dissipative response to heightened light stress on photosystem II, plausibly explaining their dominance over other algal groups in turbulent light environs. Their NPQ mechanism has been principally attributed to a xanthophyll cycle involving the lumenal pH regulated reversible de-epoxidation of diadinoxanthin. The principal goal of this dissertation is to reveal the physiological and physical origins and consequences of the NPQ response in diatoms during short-term transitions to excessive irradiation. The investigation involves diatom species from different originating light environs to highlight the diversity of diatom NPQ and to facilitate the detection of core mechanisms common among the diatoms as a group. A chiefly spectroscopic approach was used to investigate NPQ in diatom cells. Prime methodologies include: the real time monitoring of PSII excitation and de-excitation pathways via PAM fluorometry and pigment interconversion via transient absorbance measurements, the collection of cryogenic absorbance spectra to measure pigment energy levels, and the collection of cryogenic fluorescence spectra and room temperature picosecond time resolved fluorescence decay spectra to study excitation energy transfer and dissipation. Chemical inhibitors that target the trans-thylakoid pH gradient, the enzyme responsible for diadinoxanthin de-epoxidation, and photosynthetic electron flow were additionally used to experimentally manipulate the NPQ response. Multifaceted analyses of the NPQ responses from two previously un-photosynthetically characterised species, Nitzschia curvilineata and Navicula sp., were used to identify an excitation pressure relief ‘strategy’ for each species. Three key areas of NPQ were examined: (i) the NPQ activation/deactivation processes, (ii) how NPQ affects the collection, dissipation, and usage of absorbed light energy, and (iii) the interdependence of NPQ and photosynthetic electron flow. It was found that Nitzschia cells regulate excitation pressure via performing a high amplitude, reversible antenna based quenching which is dependent on the de-epoxidation of diadinoxanthin. In Navicula cells excitation pressure could be effectively regulated solely within the PSII reaction centre, whilst antenna based, diadinoxanthin de-epoxidation dependent quenching was implicated to be used as a supplemental, long-lasting source of excitation energy dissipation. These strategies for excitation balance were discussed in the context of resource partitioning under these species’ originating light climates. A more detailed investigation of the NPQ response in Nitzschia was used to develop a comprehensive model describing the mechanism for antenna centred non-photochemical quenching in this species. The experimental evidence was strongly supportive of a mechanism whereby: an acidic lumen triggers the diadinoxanthin de-epoxidation and protonation mediated aggregation of light harvesting complexes leading to the formation of quencher chlorophyll a-chlorophyll a dimers with short-lived excited states; quenching relaxes when a rise in lumen pH triggers the dispersal of light harvesting complex aggregates via deprotonation events and the input of diadinoxanthin. This model may also be applicable for describing antenna based NPQ in other diatom species.

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The sport values of female hockey players and their minor hockey associations were explored to better inform a values-based approach for adult-managed minor hockey. Data were collected from 294 participatory HL and competitive Rep players (12-22 years of age) using the Youth Sport Values Questionnaire-2 and from 30 hockey association board members using a modified YSVQ-2. Results indicated player importance (VI) ratings for Moral (M = 4.08) and Competence (M = 4.15) values were not significantly different but were significantly higher than Status (M = 2.11) value. Significant weak relationships between age and competition level versus VI ratings were found. There were medium/ high Moral, medium/ low Competence and high/ high Status value congruence between Rep and HL Player-Board Members, respectively. Based upon the findings, girls’ minor hockey associations need to recognize the values female youth players prioritize, and ensure each is considered within a values-based decision-making approach to governance.

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We provide a characterization of selection correspondences in two-person exchange economies that can be core rationalized in the sense that there exists a preference profile with some standard properties that generates the observed choices as the set of core elements of the economy for any given initial endowment vector. The approach followed in this paper deviates from the standard rational choice model in that a rationalization in terms of a profile of individual orderings rather than in terms of a single individual or social preference relation is analyzed.

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Le présent mémoire se veut être une étude critique portant sur un thème qui n’a pas été traité à ce jour : l’œuvre sculptural d’Irma Stern (1894-1966), artiste d’ascendance juive-allemande née en Afrique du Sud. Il s’agit de dégager des perspectives nouvelles sur l’art, la carrière et l’importance historique d’une personnalité qui est d’ordinaire acclamée pour sa contribution à l’essor de la peinture sud-africaine moderne. Notre visée est double. Nous proposons d’abord le premier catalogue exhaustif des sculptures d’Irma Stern : sont présentées environ trente à cinquante œuvres qui furent réalisées entre 1922 et 1955 dans divers média et dont le trait commun est de représenter des femmes africaines. Nous proposons en second lieu une analyse interprétative du corpus, dans son intégralité. Il s’agit de corréler l’œuvre sculptural d’Irma Stern aux méandres de sa vie et de son travail de peintre déterminée à représenter des sujets africains. Notre but est de parvenir à une compréhension fine des désirs, des préoccupations et des angoisses qui animèrent l’artiste dans sa confrontation, longue de trente années, avec des thèmes africains ainsi que des dynamiques de pouvoir qui se dégagent de son œuvre. En portant tour à tour notre attention aux sculptures en argile (1922), en ciment (1936-45) et enfin, en pierre à savon et en verdite (1936-45), et en empruntant aux cadres conceptuels fournis par les théories postcoloniale, phénoménologique et sculpturale, nous mettons en évidence les évolutions qu’a connues le rapport de l’artiste à son sujet et ce qu’elles nous disent sur la relation, mouvante, qu’elle entretenait avec ses modèles. Les analyses que nous proposons sont susceptibles d’ouvrir de nouvelles pistes et de modifier le regard porté à Irma Stern et à sa place dans l’histoire de l’art sud-africain.

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Geochemical composition is a set of data for predicting the climatic condition existing in an ecosystem. Both the surficial and core sediment geochemistry are helpful in monitoring, assessing and evaluating the marine environment. The aim of the research work is to assess the relationship between the biogeochemical constituents in the Cochin Estuarine System (CES), their modifications after a long period of anoxia and also to identify the various processes which control the sediment composition in this region, through a multivariate statistical approach. Therefore the study of present core sediment geochemistry has a critical role in unraveling the benchmark of their characterization. Sediment cores from four prominent zones of CES were examined for various biogeochemical aspects. The results have served as rejuvenating records for the prediction of core sediment status prevailing in the CES

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The photoionization cross sections for the production of the Kr II 4s state and Kr II satellite states were studied in the 4s ionization threshold region. The interference of direct photoionization and ionization through the autoionization decay of doubly-excited states was considered. In the calculations of doubly-excited state energies, performed by a configuration interaction technique, the 4p spin-orbit interaction and the (Kr II core)-(excited electron) Coulomb interaction were included. The theoretical cross sections are in many cases in good agreement with the measured values. Strong resonant features in the satellite spectra with threshold energies greater than 30 eV are predicted.

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The working paper’s main objective is to explore the extent to which non-compliance to international labor rights is caused by global competition. From the perspective of institutional economics, compliance with core labor rights is beneficial for sustainable development. Nonetheless, violations of these rights occur on a massive scale. The violators usually blame competitive pressures. A number of studies have come to the conclusion that non-compliance does not provide for a competitive edge, thereby denying any economic rationale for non-compliance. While we sympathize with this conclusion, we find that these studies suffer from faulty assumptions in the design of their regression analyses. The assumption of perfect markets devoid of power relations is particularly unrealistic. While workers' rights promise long-term benefits, they may incur short-term production cost increases. On the supply side, the production sites with the highest amount of labor rights violations are characterized by a near perfect competitive situation. The demand side, however, is dominated by an oligopoly of brand name companies and large retailers. Facing a large pool of suppliers, these companies enjoy more bargaining power. Developing countries, the hosts to most of these suppliers, are therefore limited in their ability to raise labor standards on their own. This competitive situation, however, is the very reason why labor rights have to be negotiated internationally. Our exploration starts with an outline of the institutionalist argument of the benefits of core labor rights. Second, we briefly examine some cross-country empirical studies on the impact of trade liberalization (as a proxy for competitive pressures). Third, we develop our own argument which differentiates the impact of trade liberalization along the axes of labor- and capital-intensive production as well as low and medium skill production. Finally, we present evidence from a study on the impact of trade liberalization in Indonesia on the garment industry as an example of a low skill, laborintensive industry on the one hand, and the automobile as an example for a medium skill, capital-intensive industry on the other hand. Because the garment industry’s workforce consists mainly of women, we also discuss the gender dimension of trade liberalization.

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A pioneer team of students of the University of Girona decided to design and develop an autonomous underwater vehicle (AUV) called ICTINEU-AUV to face the Student Autonomous Underwater Challenge-Europe (SAUC-E). The prototype has evolved from the initial computer aided design (CAD) model to become an operative AUV in the short period of seven months. The open frame and modular design principles together with the compatibility with other robots previously developed at the lab have provided the main design philosophy. Hence, at the robot's core, two networked computers give access to a wide set of sensors and actuators. The Gentoo/Linux distribution was chosen as the onboard operating system. A software architecture based on a set of distributed objects with soft real time capabilities was developed and a hybrid control architecture including mission control, a behavioural layer and a robust map-based localization algorithm made ICTINEU-AUV the winning entry

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À medida que a escola pretende cada vez mais inserir no seu seio todos os alunos, independentemente das suas características e necessidades, coloca-se um grande desafio para as instituições escolares: educar estes alunos de forma adequada. Nos últimos anos, o conceito de Inclusão foi sofrendo uma grande evolução, tendo como principio fulcral o ajuste das necessidades de aprendizagem e adaptação das perspectivas de ensino, às dificuldades dos indivíduos. A adopção de uma filosofia inclusiva tende assim, uma reestruturação da própria escola e revoga uma acção e atitude em prol dos direitos humanos e dos cidadãos. O objectivo deste estudo passa então por investigar as atitudes dos professores em relação às vantagens da educação inclusiva, quer em relação aos alunos ditos normais, quer com deficiência, e perceber de que formas essas atitudes são influenciáveis, tendo em conta o género dos docentes, e de que modo o contacto com pessoas com deficiência na infância/juventude influencia positivamente a atitude dos mesmos. O estudo foi realizado com uma amostra de 741 professores (N= 535 do género feminino e N= 206 do género masculino). Foi aplicado o questionário APIAD – A Atitude dos Professores face à Inclusão de Alunos com Deficiência (Leitão, 2011). A análise dos resultados obtidos permitiu-nos concluir que os professores que tiveram na sua infância/juventude contacto com pessoas com deficiência têm uma atitude mais favorável relativamente às vantagens da inclusão para os alunos com deficiência (p≤0,10). Relativamente ao Género dos docentes, as professoras têm uma atitude mais favorável relativamente às vantagens da inclusão do que os professores (p = 0,023). Quanto às vantagens da inclusão para os alunos normais e alunos com deficiência, os resultados mantêm-se, com uma atitude mais favorável por parte das professoras relativamente ao professores, sendo as diferenças estatisticamente significativas (p = 0,017.) e (p ≤ 0,10).ABSTRACT: While school aims at increasing the inclusion of its students, regardless of their specific characteristics or needs, there is a greater challenge for the institutions: that of educating its students adequately. In the last few years, the concept of inclusion has developed, having as its core value the adjustment of needs and the integration of teaching propositions in relation to students. The adoption of an inclusive philosophy tends, thus, to restructure the school itself and revokes certain actions and attitudes in accordance to human rights. One of the aims of this study includes the investigation of the attitudes of teachers regarding the advantages of inclusion in education, whether towards students said normal or those with a disability. Another aim is to understand how these attitudes can be influenced, taking into account the gender of faculty members and how the contact with people with disabilities in childhood/teenage years may have a positive influence in the attitudes of teachers. The study was carried out with a sample of 741 teachers (N= 535 females and N= 206 males). We used the APIAD questionnaire - A Atitude dos Professores face à Inclusão de Alunos com Deficiência/Teacher‟s Attitudes towards the Inclusion of Disabled Students (Leitão, 2011) The collected data helped us conclude that teachers who had contact with disabled people during their childhood/teenage years have a more positive attitude towards the advantages of inclusion. (p 0,10). Regarding the gender of faculty members, female teachers have a more positive attitude in relation to said advantages than male teachers (p= 0,023). As for the advantages of inclusion towards „normal‟ children and those who are disabled, the results are the same: female teachers have a more optimistic attitude than male teachers. The differences are statistically significant (p = 0.017) and (p  0,10).

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The entropy budget is calculated of the coupled atmosphere–ocean general circulation model HadCM3. Estimates of the different entropy sources and sinks of the climate system are obtained directly from the diabatic heating terms, and an approximate estimate of the planetary entropy production is also provided. The rate of material entropy production of the climate system is found to be ∼50 mW m−2 K−1, a value intermediate in the range 30–70 mW m−2 K−1 previously reported from different models. The largest part of this is due to sensible and latent heat transport (∼38 mW m−2 K−1). Another 13 mW m−2 K−1 is due to dissipation of kinetic energy in the atmosphere by friction and Reynolds stresses. Numerical entropy production in the atmosphere dynamical core is found to be about 0.7 mW m−2 K−1. The material entropy production within the ocean due to turbulent mixing is ∼1 mW m−2 K−1, a very small contribution to the material entropy production of the climate system. The rate of change of entropy of the model climate system is about 1 mW m−2 K−1 or less, which is comparable with the typical size of the fluctuations of the entropy sources due to interannual variability, and a more accurate closure of the budget than achieved by previous analyses. Results are similar for FAMOUS, which has a lower spatial resolution but similar formulation to HadCM3, while more substantial differences are found with respect to other models, suggesting that the formulation of the model has an important influence on the climate entropy budget. Since this is the first diagnosis of the entropy budget in a climate model of the type and complexity used for projection of twenty-first century climate change, it would be valuable if similar analyses were carried out for other such models.

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The formation of a lava dome involves fractionation of the lava into core and clastic components. We show that for three separate, successive andesitic lava domes that grew at Soufrière Hills volcano, Montserrat, between 1999 and 2007, the volumetric proportion of the lava converted to talus or pyroclastic flow deposits was 50%–90% of the lava extruded. Currently, only 8% of the total magma extruded during the 1995–2007 eruption remains as core lava. The equivalent representation in the geological record will probably be even lower. Most of the lava extruded at the surface flowed no further than 150–300 m from the vent before disaggregation, resulting in a lava core whose shape tends to a cylinder. Moderate to high extrusion rates at the Soufrière Hills domes may have contributed to the large clastic fraction observed. Creating talus dissipates much of the energy that would otherwise be stored in the core lava of domes. The extreme hazards from large pyroclastic flows and blasts posed by wholesale collapse of a lava dome depend largely on the size of the lava core, and hence on the aggregate history of the partitioning process, not on the size of the dome.

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The mechanisms underlying the formation of necrotic regions within avascular tumours are not well understood. In this paper, we examine the relative roles of nutrient deprivation and of cell death, from both the proliferating phase of the cell cycle via apoptosis and from the quiescent phase via necrosis, in changing the structure within multicellular tumour spheroids and particularly the accumulation of dead cell material in the centre. A mathematical model is presented and studied that accounts for nutrient diffusion, changes in cell cycling rates, the two different routes to cell death as well as active motion of cells and passive motion of the dead cell material. In studying the accumulation of dead cell matter we do not distinguish between the route by which each was formed. The resulting mathematical model is examined for a number of scenarios. Results show that in many cases the size of the necrotic core is closely correlated with low levels in nutrient concentration. However, in certain cases, particularly where the rate of necrosis is large, the resulting necrotic core can lead to regions of non-negligible nutrient concentration-dependent upon the mode of cell death.