926 resultados para Process theory


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We develop a unifying theory of hypoxia tolerance based on information from two cell level models (brain cortical cells and isolated hepatocytes) from the highly anoxia tolerant aquatic turtle and from other more hypoxia sensitive systems. We propose that the response of hypoxia tolerant systems to oxygen lack occurs in two phases (defense and rescue). The first lines of defense against hypoxia include a balanced suppression of ATP-demand and ATP-supply pathways; this regulation stabilizes (adenylates) at new steady-state levels even while ATP turnover rates greatly decline. The ATP demands of ion pumping are down-regulated by generalized "channel" arrest in hepatocytes and by "spike" arrest in neurons. Hypoxic ATP demands of protein synthesis are down-regulated probably by translational arrest. In hypoxia sensitive cells this translational arrest seems irreversible, but hypoxia-tolerant systems activate "rescue" mechanisms if the period of oxygen lack is extended by preferentially regulating the expression of several proteins. In these cells, a cascade of processes underpinning hypoxia rescue and defense begins with an oxygen sensor (a heme protein) and a signal-transduction pathway, which leads to significant gene-based metabolic reprogramming-the rescue process-with maintained down-regulation of energy-demand and energy-supply pathways in metabolism throughout the hypoxic period. This recent work begins to clarify how normoxic maintenance ATP turnover rates can be drastically (10-fold) down-regulated to a new hypometabolic steady state, which is prerequisite for surviving prolonged hypoxia or anoxia. The implications of these developments are extensive in biology and medicine.

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For almost a century, events relating to the evolutionary origin of endosperm, a unique embryo-nourishing tissue that is essential to the reproductive process in flowering plants, have remained a mystery. Integration of recent advances in phylogenetic reconstruction, comparative reproductive biology, and genetic theory can be used to elucidate the evolutionary events and forces associated with the establishment of endosperm. Endosperm is shown to be derived from one of two embryos formed during a rudimentary process of "double fertilization" that evolved in the ancestors of angiosperms. Acquisition of embryo-nourishing behavior (with accompanying loss of individual fitness) by this supernumerary fertilization product was dependent upon compensatory gains in the inclusive fitness of related embryos. The result of the loss of individual fitness by one of the two original products of double fertilization was the establishment of endosperm, a highly modified embryo/organism that reproduces cryptically through behavior that enhances the fitness of its associated embryo within a seed. Finally, although triploid endosperm remains a synapomorphy of angiosperms, inclusive fitness analysis demonstrates that the embryo-nourishing properties of endosperm initially evolved in a diploid condition.

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here are currently hundreds of thousands of children in the US foster care system who are all in need of a stable and predictable home with parents on whom they can depend. Recently, there has been an increased interest in adoption from gay couples who want to start a family. Because the majority of children in the foster care system have some sort of abuse or neglect history, a large number of them present with difficulties such as oppositional behavior, mood dysregulation, and other kinds of mental health problems. This paper addresses the unique situation of gay couples who adopt children who have been abused. Kohut's self psychology theory is utilized to help identify strengths and potential problems that could arise from this type of situation. Particular attention is given to the three selfobject needs that are central in self psychology: mirroring, idealization, and twinship. Additionally, ideas for interventions are posed for potential adoptive parents and mental health professionals to use to help the adoption process progress more smoothly and to hopefully lead to long-term, healthy placements.

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Attempts to address the ever increasing achievement gap among students have failed to explain how and why educational traditions and teaching practices perpetuate the devaluing of some and the overvaluing of others. This predicament, which plagues our educational system, has been of increased concern, given the growing racial diversity among college students and the saturation of White faculty in the academy. White faculty make up the majority, 79%, of all faculty in the academy. White faculty, whether consciously or unconsciously, are less likely to interrogate how race and racism both privilege them within the academy and influence their faculty behaviors. The result of this cyclical, highly cemented process suggests that there is a relationship between racial consciousness and White faculty members' ability to employ behaviors in their classroom that promote equitable educational outcomes for racially minoritized students. An investigation of the literature revealed that racial consciousness and the behaviors of White faculty in the classroom appeared to be inextricably linked. A conceptual framework, Racial Consciousness and Its Influence on the Behaviors of White Faculty in the Classroom was developed by the author and tested in this study. Constructivist grounded theory was used to explore the role White faculty believe they play in the dismantling of the white supremacy embedded in their classrooms through their faculty behaviors. A substantive theory subsequently emerged. Findings indicate that White faculty with a higher level of racial consciousness employ behaviors in their classroom reflective of a more expansive view of equality in their pursuit of social justice, which they consider synonymous with excellence in teaching. This research bears great significance to higher education research and practice, as it is the first of its kind to utilize critical legal scholar Kimberlé Crenshaw's (1988) restrictive and expansive views of equality framework to empirically measure and describe excellence in college teaching. Implications for faculty preparation and continued education are also discussed.

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This article examines the opinions of the local population on the south coast of the Spanish province of Alicante regarding the development of tourism in recent years, analysing their perception of the benefits of tourism using the social exchange theory. This study is presented in two stages. The qualitative stage, which is based on in-depth interviews and focus groups, acts as a guide for the second stage, which consists of a survey conducted with the resident Spanish population. It was found that people linked to the tourist sector through their work view tourism as the driving force behind the economic and social development of their towns, although they are more critical than others of the model that has been established. They defend the development process that has taken place, but feel that overcrowding brings their towns to a standstill and needs to be resolved.

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In this paper, we propose a novel filter for feature selection. Such filter relies on the estimation of the mutual information between features and classes. We bypass the estimation of the probability density function with the aid of the entropic-graphs approximation of Rényi entropy, and the subsequent approximation of the Shannon one. The complexity of such bypassing process does not depend on the number of dimensions but on the number of patterns/samples, and thus the curse of dimensionality is circumvented. We show that it is then possible to outperform a greedy algorithm based on the maximal relevance and minimal redundancy criterion. We successfully test our method both in the contexts of image classification and microarray data classification.

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This paper tests the existence of ‘reference dependence’ and ‘loss aversion’ in students’ academic performance. Accordingly, achieving a worse than expected academic performance would have a much stronger effect on students’ (dis)satisfaction than obtaining a better than expected grade. Although loss aversion is a well-established finding, some authors have demonstrated that it can be moderated – diminished, to be precise–. Within this line of research, we also examine whether the students’ emotional response (satisfaction/dissatisfaction) to their performance can be moderated by different musical stimuli. We design an experiment through which we test loss aversion in students’ performance with three conditions: ‘classical music’, ‘heavy music’ and ‘no music’. The empirical application supports the reference-dependence and loss aversion hypotheses (significant at p < 0.05), and the musical stimuli do have an influence on the students’ state of satisfaction with the grades (at p < 0.05). Analyzing students’ perceptions is vital to find the way they process information. Particularly, knowing the elements that can favour not only the academic performance of students but also their attitude towards certain results is fundamental. This study demonstrates that musical stimuli can modify the perceptions of a certain academic result: the effects of ‘positive’ and ‘negative’ surprises are higher or lower, not only in function of the size of these surprises, but also according to the musical stimulus received.

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Outliers are objects that show abnormal behavior with respect to their context or that have unexpected values in some of their parameters. In decision-making processes, information quality is of the utmost importance. In specific applications, an outlying data element may represent an important deviation in a production process or a damaged sensor. Therefore, the ability to detect these elements could make the difference between making a correct and an incorrect decision. This task is complicated by the large sizes of typical databases. Due to their importance in search processes in large volumes of data, researchers pay special attention to the development of efficient outlier detection techniques. This article presents a computationally efficient algorithm for the detection of outliers in large volumes of information. This proposal is based on an extension of the mathematical framework upon which the basic theory of detection of outliers, founded on Rough Set Theory, has been constructed. From this starting point, current problems are analyzed; a detection method is proposed, along with a computational algorithm that allows the performance of outlier detection tasks with an almost-linear complexity. To illustrate its viability, the results of the application of the outlier-detection algorithm to the concrete example of a large database are presented.

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Background: Despite the progress made on policies and programmes to strengthen primary health care teams’ response to Intimate Partner Violence, the literature shows that encounters between women exposed to IPV and health-care providers are not always satisfactory, and a number of barriers that prevent individual health-care providers from responding to IPV have been identified. We carried out a realist case study, for which we developed and tested a programme theory that seeks to explain how, why and under which circumstances a primary health care team in Spain learned to respond to IPV. Methods: A realist case study design was chosen to allow for an in-depth exploration of the linkages between context, intervention, mechanisms and outcomes as they happen in their natural setting. The first author collected data at the primary health care center La Virgen (pseudonym) through the review of documents, observation and interviews with health systems’ managers, team members, women patients, and members of external services. The quality of the IPV case management was assessed with the PREMIS tool. Results: This study found that the health care team at La Virgen has managed 1) to engage a number of staff members in actively responding to IPV, 2) to establish good coordination, mutual support and continuous learning processes related to IPV, 3) to establish adequate internal referrals within La Virgen, and 4) to establish good coordination and referral systems with other services. Team and individual level factors have triggered the capacity and interest in creating spaces for team leaning, team work and therapeutic responses to IPV in La Virgen, although individual motivation strongly affected this mechanism. Regional interventions did not trigger individual and/ or team responses but legitimated the workings of motivated professionals. Conclusions: The primary health care team of La Virgen is involved in a continuous learning process, even as participation in the process varies between professionals. This process has been supported, but not caused, by a favourable policy for integration of a health care response to IPV. Specific contextual factors of La Virgen facilitated the uptake of the policy. To some extent, the performance of La Virgen has the potential to shape the IPV learning processes of other primary health care teams in Murcia.

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The general purpose of the EQUIFASE Conference is to promote the Scientific and Technologic exchange between people from both the academic and the industrial environment in the field of Phase Equilibria and Thermodynamic Properties for the Design of Chemical Processes. Topics: Measurement of Thermodynamic Properties. Phase Equilibria and Chemical Equilibria. Theory and Modelling. Alternative Solvents. Supercritical Fluids. Ionic Liquids. Energy. Gas and oil. Petrochemicals. Environment and sustainability. Biomolecules and Biotechnology. Product and Process Design. Databases and Software. Education.

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The Surface Renewal Theory (SRT) is one of the most unfamiliar models in order to characterize fluid-fluid and fluid-fluid-solid reactions, which are of considerable industrial and academicals importance. In the present work, an approach to the resolution of the SRT model by numerical methods is presented, enabling the visualization of the influence of different variables which control the heterogeneous overall process. Its use in a classroom allowed the students to reach a great understanding of the process.

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Structuralism is a theory of U.S. constitutional adjudication according to which courts should seek to improve the decision-making process of the political branches of government so as to render it more democratic.1 In words of John Hart Ely, courts should exercise their judicial-review powers as a ‘representation-reinforcing’ mechanism.2 Structuralism advocates that courts must eliminate the elements of the political decision-making process that are at odds with the structure set out by the authors of the U.S. Constitution. The advantage of this approach, U.S. scholars posit, lies in the fact that it does not require courts to second-guess the policy decisions adopted by the political branches of government. Instead, they limit themselves to enforcing the constitutional structure within which those decisions must be adopted. Of course, this theory of constitutional adjudication, like all theories, has its shortcomings. For example, detractors of structuralism argue that it is difficult, if not impossible, to draw the dividing line between ‘substantive’ and ‘structural’ matters.3 In particular, they claim that, when identifying the ‘structure’ set out by the authors of the U.S. Constitution, courts necessarily base their determinations not on purely structural principles, but on a set of substantive values, evaluating concepts such as democracy, liberty and equality. 4 Without claiming that structuralism should be embraced by the ECJ as the leading theory of judicial review, the purpose of my contribution is to explore how recent case-law reveals that the ECJ has also striven to develop guiding principles which aim to improve the way in which the political institutions of the EU adopt their decisions. In those cases, the ECJ decided not to second-guess the appropriateness of the policy choices made by the EU legislator. Instead, it preferred to examine whether, in reaching an outcome, the EU political institutions had followed the procedural steps mandated by the authors of the Treaties. Stated simply, I argue that judicial deference in relation to ‘substantive outcomes’ has been counterbalanced by a strict ‘process review’. To that effect, I would like to discuss three recent rulings of the ECJ, delivered after the entry into force of the Treaty of Lisbon, where an EU policy measure was challenged indirectly, i.e. via the preliminary reference procedure, namely Vodafone, Volker und Markus Schecke and Test-Achats.5 Whilst in the former case the ECJ ruled that the questions raised by the referring court disclosed no factor of such a kind as to affect the validity of the challenged act, in the latter cases the challenged provisions of an EU act were declared invalid.

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The Western Balkans integration within the EU has started a legal process which is the rejection of former communist legal/political approaches and the transformation of former communist institutions. Indeed, the EU agenda has brought vertical/horizontal integration and Europeanization of national institutions (i.e. shifting power to the EU institutions and international authorities). At this point, it is very crucial to emphasize the fact that the Western Balkans as a whole region has currently an image that includes characteristics of both the Soviet socialism and the European democracy. The EU foreign policies and enlargement strategy for Western Balkans have significant effects on four core factors (i.e. Schengen visa regulations, remittances, asylum and migration as an aggregate process). The convergence/divergence of EU member states’ priorities for migration policies regulate and even shape directly the migration dynamics in migrant sender countries. From this standpoint, the research explores how main migration factors are influenced by political and judicial factors such as; rule of law and democracy score, the economic liberation score, political and human rights, civil society score and citizenship rights in Western Balkan countries. The proposal of interhybridity explores how the hybridization of state and non-state actors within home and host countries can solve labor migration-related problems. The economical and sociopolitical labor-migration model of Basu (2009) is overlapping with the multidimensional empirical framework of interhybridity. Indisputably, hybrid model (i.e. collaboration state and non-state actors) has a catalyst role in terms of balancing social problems and civil society needs. Paradigmatically, it is better to perceive the hybrid model as a combination of communicative and strategic action that means the reciprocal recognition within the model is precondition for significant functionality. This will shape social and industrial relations with moral meanings of communication.

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Thesis (M.A.)--University of Illinois at Urbana-Champaign.

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Mineral processing plants use two main processes; these are comminution and separation. The objective of the comminution process is to break complex particles consisting of numerous minerals into smaller simpler particles where individual particles consist primarily of only one mineral. The process in which the mineral composition distribution in particles changes due to breakage is called 'liberation'. The purpose of separation is to separate particles consisting of valuable mineral from those containing nonvaluable mineral. The energy required to break particles to fine sizes is expensive, and therefore the mineral processing engineer must design the circuit so that the breakage of liberated particles is reduced in favour of breaking composite particles. In order to effectively optimize a circuit through simulation it is necessary to predict how the mineral composition distributions change due to comminution. Such a model is called a 'liberation model for comminution'. It was generally considered that such a model should incorporate information about the ore, such as the texture. However, the relationship between the feed and product particles can be estimated using a probability method, with the probability being defined as the probability that a feed particle of a particular composition and size will form a particular product particle of a particular size and composition. The model is based on maximizing the entropy of the probability subject to mass constraints and composition constraint. Not only does this methodology allow a liberation model to be developed for binary particles, but also for particles consisting of many minerals. Results from applying the model to real plant ore are presented. A laboratory ball mill was used to break particles. The results from this experiment were used to estimate the kernel which represents the relationship between parent and progeny particles. A second feed, consisting primarily of heavy particles subsampled from the main ore was then ground through the same mill. The results from the first experiment were used to predict the product of the second experiment. The agreement between the predicted results and the actual results are very good. It is therefore recommended that more extensive validation is needed to fully evaluate the substance of the method. (C) 2003 Elsevier Ltd. All rights reserved.